Science.gov

Sample records for pn charge-exchange-process yields

  1. The ratio R{sub dp} of the quasielastic nd {yields} p(nn) to the elastic np {yields} pn charge-exchange-process yields at the proton emitting angle {theta}{sub p,lab} = 0 deg. over 0.55-2.0 GeV neutron beam energy region. Experimental results

    SciTech Connect

    Sharov, V. I. Morozov, A. A.; Shindin, R. A.; Antonenko, V. G.; Borzakov, S. B.; Borzunov, Yu. T.; Chernykh, E. V.; Chumakov, V. F.; Dolgii, S. A.; Finger, M.; Finger, M.; Golovanov, L. B.; Guriev, D. K.; Janata, A.; Kirillov, A. D.; Kovalenko, A. D.; Krasnov, V. A.; Kuzmin, N. A.; Kurilkin, A. K.; Kurilkin, P. K.

    2009-06-15

    New experimental results on ratio R{sub dp} of the quasielastic charge-exchange yield at the outgoing proton angle {theta}{sub p,lab} = 0 deg. for the nd {yields} p(nn) reaction to the elastic np {yields} pn charge-exchange yield, are presented. The measurements were carried out at the Nuclotron of the Veksler and Baldin Laboratory of High Energies of the JINR (Dubna) at the neutron-beam kinetic energies of 0.55, 0.8, 1.0, 1.2, 1.4, 1.8, and 2.0 GeV. The intense neutron beam with small momentum spread was produced by breakup of deuterons which were accelerated and extracted to the experimental hall. In both reactions mentioned above the outgoing protons with the momenta p{sub p} approximately equal to the neutron-beam momentum p{sub n,beam} were detected in the directions close to the direction of incident neutrons, i.e., in the vicinity of the scattering angle {theta}{sub p,lab} = 0 deg. Measured in the same data-taking runs, the angular distributions of the charge-exchange-reaction products were corrected for the well-known instrumental effects and averaged in the vicinity of the incident-neutron-beam direction. These corrected angular distributions for every of nd {yields} p(nn) and np {yields} pn charge-exchange processes were proportional to the differential cross sections of the corresponding reactions. The data were accumulated by Delta-Sigma setup magnetic spectrometer with two sets of multiwire proportional chambers located upstream and downstream of the momentum analyzing magnet. Inelastic processes were considerably reduced by the additional detectors surrounding the hydrogen and deuterium targets. The time-of-flight system was applied to identify the detected particles. The accumulated data treatment and analysis, as well as possible sources of the systematic errors are discussed.

  2. Efficient prediction of (p,n) yields

    SciTech Connect

    Swift, D C; McNaney, J M; Higginson, D P; Beg, F

    2009-09-09

    In the continuous deceleration approximation, charged particles decelerate without any spread in energy as they traverse matter. This approximation simplifies the calculation of the yield of nuclear reactions, for which the cross-section depends on the particle energy. We calculated (p,n) yields for a LiF target, using the Bethe-Bloch relation for proton deceleration, and predicted that the maximum yield would be around 0.25% neutrons per incident proton, for an initial proton energy of 70 MeV or higher. Yield-energy relations calculated in this way can readily be used to optimize source and (p,n) converter characteristics.

  3. Solar System X-rays from Charge Exchange Processes

    NASA Astrophysics Data System (ADS)

    Lisse, Carey M.; Christian, D. J.; Bhardwaj, A.; Dennerl, K.; Wolk, S. J.; Bodewits, D.; Combi, M. R.; Zurbuchen, T. H.; Lepri, S. T.

    2013-04-01

    The discovery of high energy x-ray emission in 1996 from comet C/1996 B2 (Hyakutake) uncovered a new class of x-ray emitting objects. Subsequent detections of the morphology, spectra, and time dependence of the x-rays from more than 20 comets have shown that the very soft (E < 1 keV) emission is due to a charge-exchange interaction between highly charged solar wind minor ions and the comet's extended neutral atmosphere. Many solar system objects are now known to shine in the X-ray, including Venus, Mars, the Moon, the Earth, Jupiter, and Saturn, with total power outputs on the MW - GW scale. Like comets, the X-ray emission from the Earth's geo-corona, the Jovian & Saturnian aurorae, and the Martian halo are thought to be driven by charge exchange between highly charged minor (heavy) ions in the solar wind and gaseous neutral species in the bodies' atmosphere. The non-auroral X-ray emissions from Jupiter, Saturn, and Earth, and those from disks of Mars, Venus, and the Moon are produced by scattering of solar X-rays. The first soft X-ray observations of Earth’s aurora by Chandra shows that it is highly variable, and the giant planet aurorae are fascinating puzzles that are just beginning to yield their secrets and may be the only x-ray sources not driven directly by the Sun in the whole system as well as properties of hot exo-solar Jupiters. Observations of local solar system charge exchange processes can also help inform us about x-rays produced at more distant hot ionized gas/cold neutral gas interfaces, like the heliopause, stellar astrospheres, galactic star forming regions, and starburst galaxies.

  4. Modeling the Hydrogen-Proton Charge-Exchange Process in Global Heliospheric Simulations

    NASA Astrophysics Data System (ADS)

    DeStefano, A.; Heerikhuisen, J.

    2015-12-01

    The environment surrounding our Solar System has a vast and dynamic structure. As the Sun rounds the Milky Way galaxy, interstellar dust and gas interact with the Sun's outflow of solar wind. A bubble of hot plasma forms around the Sun due to this interaction, called the heliosphere. In order to understand the structure of the heliosphere, observations and simulations must work in tandem. Within the past decade or so, 3D models of the heliosphere have been developed exhibiting non- symmmetric as well as predicting structures such as the hydrogen wall and the IBEX ribbon. In this poster we explore new ways to compute charge-exchange source terms. The charge-exchange process is the coupling mechanism between the MHD and kinetic theories. The understanding of this process is crucial in order to make valuable predictions. Energy dependant cross section terms will aid in settling non-linear affects coupling the intestellar and solar particles. Through these new ways of computing source terms, resolving fine structures in the plasma in the heliopause may be possible. In addition, other non-trivial situations, such as charge-exchange mediated shocks, may be addressed.

  5. Dynamics of the fully stripped ion-hydrogen atom charge exchange process in dense quantum plasmas

    SciTech Connect

    Zhang, Ling-yu; Wan, Jiang-feng; Zhao, Xiao-ying; Xiao, Guo-qing; Duan, Wen-shan; Qi, Xin; Yang, Lei

    2014-09-15

    The plasma screening effects of dense quantum plasmas on charge exchange processes of a fully stripped ion colliding with a hydrogen atom are studied by the classical trajectory Monte Carlo method. The inter-particle interactions are described by the exponential cosine-screened Coulomb potentials. It is found that in weak screening conditions, cross sections increase with the increase of the ionic charge Z. However, in strong screening conditions, the dependence of cross sections on the ionic charge is related to the incident particle energy. At high energies, cross sections show a linear increase with the increase of Z, whereas at low energies, cross sections for Z≥4 become approximately the same. The He{sup 2+} and C{sup 6+} impacting charge exchange cross sections in dense quantum plasmas are also compared with those in weakly coupled plasmas. The interactions are described by the static screened Coulomb potential. It is found that for both He{sup 2+} and C{sup 6+}, the oscillatory screening effects of dense quantum plasmas are almost negligible in weak screening conditions. However, in strong screening conditions, the oscillatory screening effects enhance the screening effects of dense quantum plasmas, and the enhancement becomes more and more significant with the increase of the screening parameter and the ionic charge.

  6. Photocurrent Quantum Yield in Suspended Carbon Nanotube p-n Junctions.

    PubMed

    Aspitarte, Lee; McCulley, Daniel R; Minot, Ethan D

    2016-09-14

    We study photocurrent generation in individual suspended carbon nanotube p-n junctions using spectrally resolved scanning photocurrent microscopy. Spatial maps of the photocurrent allow us to determine the length of the p-n junction intrinsic region, as well as the role of the n-type Schottky barrier. We show that reverse-bias operation eliminates complications caused by the n-type Schottky barrier and increases the length of the intrinsic region. The absorption cross-section of the CNT is calculated using an empirically verified model, and the effect of substrate reflection is determined using FDTD simulations. We find that the room temperature photocurrent quantum yield is approximately 30% when exciting the carbon nanotube at the S44 and S55 excitonic transitions. The quantum yield value is an order of magnitude larger than previous estimates. PMID:27575386

  7. Yield ratio estimates using regional Pn and Pg from North Korea's underground nuclear explosions

    NASA Astrophysics Data System (ADS)

    Kim, Tae Sung; Kang, Ik-Bum; Kim, Geun-Young

    2009-11-01

    On May 25, 2009 North Korea executed a second nuclear test in the vicinity of P'unggyeri where the first nuclear test was performed on October 9, 2006. Seismic signals from the two underground nuclear explosions (UNEs) are recorded at broadband stations in South Korea and China. Seismic signals from fourteen broadband stations operated by the Korea Institute of Geoscience and Mineral Resources (KIGAM), three broadband stations of Korea Meteorological Administration (KMA) in South Korea and the Mudanjiang station (MDJ) of GSN in China are used for this study. Clear Pn, Pg, and Lg phases propagated over 800 km. The nearly co-located two UNEs and seismic recordings at the same stations enable us to estimate the ratio of the Pn and Pg displacement amplitude spectra between two events by eliminating the path effect. The 95% confidence interval of the mean yield ratio is constrained as a function of the depth ratio and all the estimates of Pn and Pg spectral ratios. The mean yield ratio ranges from 3.45 to 6.36 in the 95% confidence interval based on the depth range estimates by Bennett (2008, 2009).

  8. What can be Learned from X-ray Spectroscopy Concerning Hot Gas in Local Bubble and Charge Exchange Processes?

    NASA Technical Reports Server (NTRS)

    Snowden, Steve

    2007-01-01

    What can be learned from x-ray spectroscopy in observing hot gas in local bubble and charge exchange processes depends on spectral resolution, instrumental grasp, instrumental energy band, signal-to-nose, field of view, angular resolution and observatory location. Early attempts at x-ray spectroscopy include ROSAT; more recently, astronomers have used diffuse x-ray spectrometers, XMM Newton, sounding rocket calorimeters, and Suzaku. Future observations are expected with calorimeters on the Spectrum Roentgen Gamma mission, and the Solar Wind Charge Exchange (SWCX). The Geospheric SWCX may provide remote sensing of the solar wind and magnetosheath and remote observations of solar CMEs moving outward from the sun.

  9. Proposal for studying N* resonances with the pp{yields}pn{pi}{sup +} reaction

    SciTech Connect

    Wu Jiajun; Zou, B. S.; Ouyang Zhen

    2009-10-15

    A theoretical study of the pp{yields}pn{pi}{sup +} reaction for antiproton beam energy from 1 to 4 GeV is made by including contributions from various known N* and {delta}* resonances. It is found that for the beam energy around 1.5 GeV, the contribution of the Roper resonance N{sub (1440)}* produced by the t-channel {sigma} exchange dominates over all other contributions. Since such a reaction can be studied in the forthcoming PANDA experiment at the GSI Facility of Antiproton and Ion Research (FAIR), the reaction will be realistically the cleanest place for studying the properties of the Roper resonance and the best place for looking for other ''missing''N* resonances with large coupling to N{sigma}.

  10. Models of stellar population at high redshift, as constrained by PN yields and luminosity function

    NASA Astrophysics Data System (ADS)

    Maraston, Claudia

    2015-08-01

    Stellar population models are the tool to derive the properties of real galaxies, or predict them via galaxy formation models. A constructive approach is to use nearby stellar systems to calibrate uncertain quantities in stellar evolution. These checks and comparisons are particulary needed for evolved and short stellar phases such as the Thermally-Pulsing Asymptotic giant branch, after whcih intermediate-mass stars evolve through the planetary nebula stage. Given the stellar mass range for which the fuel consumption along the TP-AGB is larger, high-redshift galaxies are the best probes of our modelling. I shall present the models, discuss how different prescription for the treatment of this stellar phase affects the integrated spectral energy distribution and how these compare to galaxy data, and discuss implications for the PN nebulae luminosity function and stellar remnants stemming from the various assumptions.

  11. High-Yield Growth and Characterization of ⟨100⟩ InP p-n Diode Nanowires.

    PubMed

    Cavalli, Alessandro; Wang, Jia; Esmaeil Zadeh, Iman; Reimer, Michael E; Verheijen, Marcel A; Soini, Martin; Plissard, Sebastien R; Zwiller, Val; Haverkort, Jos E M; Bakkers, Erik P A M

    2016-05-11

    Semiconductor nanowires are nanoscale structures holding promise in many fields such as optoelectronics, quantum computing, and thermoelectrics. Nanowires are usually grown vertically on (111)-oriented substrates, while (100) is the standard in semiconductor technology. The ability to grow and to control impurity doping of ⟨100⟩ nanowires is crucial for integration. Here, we discuss doping of single-crystalline ⟨100⟩ nanowires, and the structural and optoelectronic properties of p-n junctions based on ⟨100⟩ InP nanowires. We describe a novel approach to achieve low resistance electrical contacts to nanowires via a gradual interface based on p-doped InAsP. As a first demonstration in optoelectronic devices, we realize a single nanowire light emitting diode in a ⟨100⟩-oriented InP nanowire p-n junction. To obtain high vertical yield, which is necessary for future applications, we investigate the effect of the introduction of dopants on the nanowire growth. PMID:27045232

  12. Determination of {sup 16}O and {sup 18}O sensitivity factors and charge-exchange processes in low-energy ion scattering

    SciTech Connect

    Tellez, H.; Chater, R. J.; Fearn, S.; Symianakis, E.; Kilner, J. A.; Brongersma, H. H.

    2012-10-08

    Quantitative analysis in low-energy ion scattering (LEIS) requires an understanding of the charge-exchange processes to estimate the elemental sensitivity factors. In this work, the neutralization of He{sup +} scattered by {sup 18}O-exchanged silica at energies between 0.6 and 7 keV was studied. The process is dominated by Auger neutralization for E{sub i} < 0.8 keV. An additional mechanism starts above the reionization threshold. This collision-induced neutralization becomes the dominant mechanism for E{sub i} > 2 keV. The ion fractions P{sup +} were determined for Si and O using the characteristic velocity method to quantify the surface density. The {sup 18}O/{sup 16}O sensitivity ratio indicates an 18% higher sensitivity for the heavier O isotope.

  13. The influence of inner-shell electron promotion on charge exchange processes in low energy ion scattering from surfaces

    NASA Astrophysics Data System (ADS)

    Ting Li; MacDonald, R. J.

    1997-11-01

    The influence of inner-shell electron promotion on charge exchange in low energy (1-7 keV) Ne + ions scattered from the Cu (1 0 0), Ni (1 0 0) and Fe (1 1 0) surfaces has been studied systematically. The yield of Ne + ion scattered from these surfaces has been measured as a function of incident ion energy under various scattering geometries. The relative Ne + ion fraction, which is proportional to the normalised ion yield divided by the differential scattering cross section, is studied and an empirical formula for relative ion fraction has been extracted. The formula combines the charge exchanges along the incoming trajectory, during the close encounter, and along the outgoing trajectory into one simple expression. It can be concluded that inner-shell electron excitations during close encounters contribute significantly to the charge exchange in the scattering systems studied in this work.

  14. Predicted neutron yield and radioactivity for laser-induced (p,n) reactions in LiF

    SciTech Connect

    Swift, D C; McNaney, J M

    2009-01-30

    Design calculations are presented for a pulsed neutron source comprising polychromatic protons accelerated from a metal foil by a short-pulse laser, and a LiF converter in which (p,n) reactions occur. Although the proton pulse is directional, neutrons are predicted to be emitted relatively isotropically. The neutron spectrum was predicted to be similar to the proton spectrum, but with more neutrons of low energy in the opposite direction to the incident protons. The angular dependence of spectrum and intensity was predicted. The (p,n) reactions generate unstable nuclei which decay predominantly by positron emission to the original {sup 7}Li and {sup 19}F isotopes. For the initial planned experiments using a converter 1mm thick, we predict that 0.1% of the protons will undergo a (p,n) reaction, producing 10{sup 9} neutrons. Ignoring the unreacted protons, neutrons, and prompt gamma emission as excited nuclear states decay, residual positron radioactivity (and production of pairs of 511 keV annihilation photons) is initially 4.2MBq decaying with a half-life of 17.22 s for 6 mins ({sup 19}Ne decays), then 135Bq decaying with a half-life of 53.22 days ({sup 7}Be decays).

  15. Investigation of the p+N {yields} [{Sigma}{sup 0}K{sup +}]+N reaction at the proton energy E{sub p} = 70 GeV

    SciTech Connect

    1994-08-01

    The p+N {yields} [{Sigma}{sup 0}K{sup +}]+N reaction was studied in experiments using the SPHINX detector placed in the 70-GeV proton beam of the IHEP accelerator. In the effective mass spectrum of the M({Sigma}{sup 0}K{sup +}) system produced in the coherent diffractive transition, a clear peak with mass M = 1999 {+-} 7 MeV and width {Gamma} = 91 {+-} 17 MeV was observed in addition to the near-threshold structure with mass M {approx_equal} 1800 MeV. 7 refs., 3 figs.

  16. Charge-exchange processes in collisions of H+,H2+,H3+,He+ , and He2+ ions with CO and CO2 molecules at energies below 1000 eV

    NASA Astrophysics Data System (ADS)

    Werbowy, S.; Pranszke, B.

    2016-02-01

    Absolute measurements of charge-exchange cross sections of H+,H2+,H3+,He+, and He2+ ions in CO and CO2 have been made for energies below 1000 eV, an equivalent of the energy of ionized particles at typical solar-wind conditions. An attenuation method for the case of complex ions of a molecule, taking into account the influence on the ion beam composition of the processes of disintegration of the primary ions into secondary ones with different charge-exchange cross sections, is described. Also the secondary effects, like three-body collisions and re-ionization processes that could emerge at higher pressures of the gas layer, are discussed. Dependence of the cross sections on the number of atomic centers in the projectile have been explained on the basis of the energy defect of the reactions and asymmetric near-resonant charge-exchange process between the ion and target molecule including the Doppler broadening in the interaction of the monoenergetic ion beam and target molecules having an isotropic Maxwellian velocity distribution corresponding to room temperature. Using the semiempirical approach based on the parametrized numerical coupled-channel two-state calculations, we have extrapolated the cross sections to a broader range of velocities.

  17. PnMPI

    Energy Science and Technology Software Center (ESTSC)

    2008-02-01

    PnMPI is a tool infrastructure for parallel programs implemented using the message passing interface (MPI). It enables users to dynamically assemble multiple tools, both existing and newly developed ones, into a single tool chain and to execute them concurrently. This provides new options for scalable tools designs including (but not concurrently. This provides new options for scalable tool designs including (but not limited to) the transparent virtualization of MPI environments of an application. In addition,more » PnMPI allows tools to export support routines to other tools. This promotes a separation of tasks between tools which leads to enhanced tool modularity. PnMPI has been implemented for a variety of platforms including Linux and AIX clusters, and a static version of PnMPI is available on Blue Gene/L.« less

  18. Charge-Exchange Processes of Titanium-Doped Aluminate Crystals

    NASA Astrophysics Data System (ADS)

    Wong, Wing Cheong

    1995-01-01

    Titanium exists in more than one charge state in the aluminate crystals: it is stable as Ti^ {3+} and Ti^{4+}. Other than the intense Ti^{4+ } absorption, a ubiquitous absorption/luminescence excitation band in the UV region is identified as a titanium -bound exciton in Al_2rm O_3, Y_3Al_5rm O_{12}, {rm YAlO}_3, MgAl_2O _4, and LaMgAl_{11} {rm O}_{19}. One -step and two-step photoconductivities of Ti^ {3+} are measured and compared. While the selectivity of the two-step process is demonstrated, its use in locating the energy threshold is hampered by the small Franck-Condon factor for the transition between the Ti^{3+} ^2{ rm E} excited state and Ti^ {4+}. The titanium-bound exciton band, together with the one-step photocurrent signal, makes it possible to determine the photoionization energy threshold accurately. The charge-transfer transition energy thresholds of Ti^{4+} are obtained from the emission and the luminescence excitation spectra. Locally and non-locally charge compensated Ti^{4+ } are found in Al_2{rm O}_3. The luminescence kinetics for the two kinds of Ti^{4+} are well explained by a three-level system with a lower triplet excited state and a higher singlet excited state. These charge-exchange threshold energies can be deduced from the Born-Haber thermodynamical cycle. The electrostatic site potentials are calculated and from it, the calculated photoionization and charge-transfer energy thresholds are found to be consistent with the experimental results. The deficiency of this model is pointed out and possible improvement is discussed. Quantitatively, the sum of the two charge-exchange energy thresholds is close to the band-gap energy of the host crystal. This offers a convenient way for material characterization. Provided that any two of the three quantities (band-gap energy, photoionization energy threshold, and charge-transfer transition energy threshold) have been found, the third quantity can be calculated. In addition, the trapping of charge carriers is investigated with thermally-stimulated conductivity and thermally-stimulated luminescence. The identities of the electron traps and hole traps are deduced from the results of several differently doped Al_2{ rm O}_3..

  19. Electrical properties of multi p-n junction devices

    NASA Technical Reports Server (NTRS)

    Katz, J.; Margalit, S.; Yariv, A.

    1982-01-01

    The electrical properties of multi p-n junction devices are analyzed. It is found that this type of device possesses bistable characteristics similar to that of a Shockley diode and thus provides an alternative realization of devices for switching applications. The inherently greater current gains involved in the operations of such a device yield in principle higher breakover voltages and higher holding currents. Furthermore, the incorporation of heterostructures in this device introduces a new degree of freedom in tailoring their switching characteristics. Multi p-n heterojunction devices operating as SCR lasers were fabricated, and the experimental results are presented.

  20. The Magellanic Cloud PN population

    NASA Astrophysics Data System (ADS)

    Reid, Warren Alfred

    2015-08-01

    The Magellanic Clouds (MCs) become an area of focus when comparing how objects behave within low metallicity environments. Over the past few decades this has proven especially true of planetary nebulae (PNe) studies. The Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) allow us to study late stellar evolution in environments that are respectively about a half and a quarter the metallicity of the Milky Way. With a known distance and low reddening, the MCs allow the analysis of PNe across a whole galaxy and have value for multiple studies.Over the past twelve months we have used the UKST H-alpha survey to complete our search for faint PNe in the outer most LMC beyond the 64 deg2 area previously covered. Follow-up spectroscopy using AAOmega on the AAT and the 2.3m telescope at Siding Spring Observatory have yielded a further 132 new LMC PNe while confirming the 102 previously known in the outer LMC. Using the same method, we have confirmed 6 new PNe in the SMC and rejected several objects previously catalogued as PNe.Medium- and high-resolution spectra have been used to measure fluxes and derive central star temperatures for a series of research projects. Recent findings involving chemical abundances, central star properties and kinematics will be presented. The current [OIII]-based PNLF, apart from providing an excellent standard candle, contains information about the parent population. The new PNLF, which extends down 9 magnitudes, permits investigation of the faint end and provides clues to explain the insensitivity of the PNLF cutoff.To better understand the global properties of PNe I will present and compare H-alpha, NIR & MIR PNLFs, discuss PN dust properties and the changes that occur as PNe age. The positions of LMC PNe will then be shown as a function of their radial velocities and compared to the HI disk and other populations. I will also discuss recent radio confirmations of LMC and SMC PNe. Finally I will also take a look at recent multi

  1. PN junction fabrication of solar cells and integration with metamaterials

    NASA Astrophysics Data System (ADS)

    Enemuo, Amarachukwu; Crouse, David T.; Crouse, Michael

    2011-05-01

    Silicon is the primary material used for the fabrication of solar cells and it is responsible for about 40% of the cost. Metamaterials show promise in enhancing the performance of silicon solar cells thus, improving the efficiency. Here we report on the fabrication of a broadband, antireflective, conductive metamaterial capable of channeling light into a solar cell. As a precursor to making the metamaterial, standard p-n junctions were fabricated. Conventional phosphorus oxychloride (POCl3) furnace diffusion was used to create the p-n junction. When the p-n junction was forward biased, the measured current exhibited a diode characteristic. The measured photocurrent response yielded an open circuit voltage for the p-n junction at 0.48 VDC. The metamaterial film was fabricated, placed atop the p-n junction and characterized. Initial tests showed that the metamaterial antireflective properties were on par with those of standard industrial single-layer silicon nitride coatings. Further testing is being performed to assess the full optical and electrical performance of the metamaterial film.

  2. Single gate p-n junctions in graphene-ferroelectric devices

    NASA Astrophysics Data System (ADS)

    Hinnefeld, J. Henry; Xu, Ruijuan; Rogers, Steven; Pandya, Shishir; Shim, Moonsub; Martin, Lane W.; Mason, Nadya

    2016-05-01

    Graphene's linear dispersion relation and the attendant implications for bipolar electronics applications have motivated a range of experimental efforts aimed at producing p-n junctions in graphene. Here we report electrical transport measurements of graphene p-n junctions formed via simple modifications to a PbZr0.2Ti0.8O3 substrate, combined with a self-assembled layer of ambient environmental dopants. We show that the substrate configuration controls the local doping region, and that the p-n junction behavior can be controlled with a single gate. Finally, we show that the ferroelectric substrate induces a hysteresis in the environmental doping which can be utilized to activate and deactivate the doping, yielding an "on-demand" p-n junction in graphene controlled by a single, universal backgate.

  3. Asymptotic derivation and numerical investigation of time-dependent simplified PN equations

    NASA Astrophysics Data System (ADS)

    Olbrant, E.; Larsen, E. W.; Frank, M.; Seibold, B.

    2013-04-01

    The steady-state simplified PN (SPN) approximations to the linear Boltzmann equation have been proven to be asymptotically higher-order corrections to the diffusion equation in certain physical systems. In this paper, we present an asymptotic analysis for the time-dependent simplified PN equations up to N=3. Additionally, SPN equations of arbitrary order are derived in an ad hoc way. The resulting SPN equations are hyperbolic and differ from those investigated in a previous work by some of the authors. In two space dimensions, numerical calculations for the PN and SPN equations are performed. We simulate neutron distributions of a moving rod and present results for a benchmark problem, known as the checkerboard problem. The SPN equations are demonstrated to yield significantly more accurate results than diffusion approximations. In addition, for sufficiently low values of N, they are shown to be more efficient than PN models of comparable cost.

  4. m b( Pn) Scale for the Korean Peninsula and Site-Dependent Pn Amplification

    NASA Astrophysics Data System (ADS)

    Hong, Tae-Kyung; Lee, Kiwook

    2012-11-01

    The Korean Peninsula is located in the far-eastern Eurasian plate margin where crustal structures vary laterally, causing significant raypath-dependent modulations of crustal phases. The discriminative variations of crustal phases hinder application of conventional local magnitude scales in the continental margin. The mantle-lid phase is less affected by the crustal structures than the crustal phases, providing a better constraint to magnitude estimation. A regional body-wave magnitude scale based on the mantle-lid P wave ( Pn), m b( Pn), is developed for regional events around the Korean Peninsula. The m b( Pn) scale is determined to be m b( Pn) = 0.380 (±0.299) + log A + 2.012 (±0.122) log d, where A is the peak-to-peak Pn amplitude in μm and d is the epicentral distance in km. The m b( Pn) estimates of regional events around the Korean Peninsula are determined. The m b( Pn) estimates are compared with other available magnitude estimates ( m b( Lg), M L). The influence of structures beneath stations on Pn amplification is investigated from inter-station magnitude residuals. A characteristic spatial variation of inter-station magnitude residuals with strengths mostly between -6 and 6 %, but with maximum strengths of ±10 %, is observed. The inter-station magnitude residuals appears to be correlated well with geological and seismic structures in the crust.

  5. Silicon fiber with p-n junction

    SciTech Connect

    Homa, D.; Cito, A.; Pickrell, G.; Hill, C.; Scott, B.

    2014-09-22

    In this study, we fabricated a p-n junction in a fiber with a phosphorous doped silicon core and fused silica cladding. The fibers were fabricated via a hybrid process of the core-suction and melt-draw techniques and maintained overall diameters ranging from 200 to 900 μm and core diameters of 20–800 μm. The p-n junction was formed by doping the fiber with boron and confirmed via the current-voltage characteristic. The demonstration of a p-n junction in a melt-drawn silicon core fiber paves the way for the seamless integration of optical and electronic devices in fibers.

  6. Physical properties of Mn oxypnictide (LaO)MnPn; Pn = P, As, Sb

    NASA Astrophysics Data System (ADS)

    Onizawa, M.; Otsuka, S.; Takeda, R.; Kato, K.; Umeyama, N.; Ikeda, S.; Hiramoto, S.; Yoshida, F.; Moriyoshi, C.; Kuroiwa, Y.; Tobimatu, K.; Sato, H.; Sawada, M.; Namatame, H.; Taniguchi, M.; Watanabe, T.; Takano, Y.; Takase, K.

    2011-12-01

    We have investigated physical properties of the layered Mn oxypnictides (LaO)MnPn; Pn = P, As, Sb. Electrical resistivity of three samples, indicting semiconducting behaviors, drastically increases with lowering temperature. The optical band gaps estimated from the diffusive reflectance are about 1.6 eV and they don't depend on pnictogen atoms even though the lattice constants widely change. Magnetizations of (LaO)MnAs and (LaO)MnSb show very weak temperature dependence with positive slope against temperature. Some magnetic order is expected to exist at higher temperature than room temperature. Consequently, the Mn oxypnictides (LaO)MnPn are magnetic semiconductors.

  7. On the auto and cross correlation of PN sequences

    NASA Technical Reports Server (NTRS)

    Morakis, J. C.

    1969-01-01

    The autocorrelation and crosscorrelation properties of pseudorandom (PN) sequences are analyzed by using some important properties of PN sequences. These properties make this discussion understandable without the need of linear algebraic approach. The analysis is followed by some experimental results.

  8. Fabrication and characterization of graphene PN junctions

    NASA Astrophysics Data System (ADS)

    Wang, Dennis; Zhou, Xiaodong; Dadgar, Ali; Agnihotri, Pratik; Lee, Ji Ung; Reuter, Mark; Ross, Frances; Pasupathy, Abhay

    Theoretical predictions of relativistic Klein tunneling and Veselago lensing in graphene have inspired efforts to fabricate graphene p-n junctions where such phenomena could be realized and studied via electronic transport or scanning tunneling microscopy (STM). Here we will discuss the interplay between device geometry and our measurements in a 4-probe STM, which allows for simultaneous back gating, biasing, and scanning of a micromechanically exfoliated graphene sample. A sharp p-n junction is essential to the manifestation of these aforementioned effects, and we examine the benefits and drawbacks of several routes toward this goal from a fabrication standpoint. These methods include lithographically pre-patterned substrates and the stacking of vertical heterostructures. Finally, we will describe our subsequent characterization results for each, including information about topography and spatial mapping of the density of states. This work is supported by NSF IGERT (DGE-1069240).

  9. TDRSS telecommunication system PN code analysis

    NASA Technical Reports Server (NTRS)

    Gold, R.

    1977-01-01

    The pseudonoise (PN) code library for the Tracking and Data Relay Satellite System (TDRSS) Services was defined and described. The code library was chosen to minimize user transponder hardware requirements and optimize system performance. Special precautions were taken to insure sufficient code phase separation to minimize cross-correlation sidelobes, and to avoid the generation of spurious code components which would interfere with system performance.

  10. Band alignments of InGaPN/GaPN quantum well structures on GaP and Si

    NASA Astrophysics Data System (ADS)

    Umeno, Kazuyuki; Kim, Sung Man; Furukawa, Yuzo; Yonezu, Hiroo; Wakahara, Akihiro

    2007-04-01

    We proposed a calculation method for the band alignment of a novel InGaPN/GaPN single-quantum well (SQW) on GaP and Si substrates. The calculation method composed the model-solid theory (MST) for the band edge shifts due to strain and the band anticrossing (BAC) model for a large band bowing of an InGaPN alloy due to N incorporation. The band alignments of the InGaPN/GaPN SQW with In compositions larger than 27% on GaP and Si substrates were investigated by the calculation method, whose QW could have a direct bandgap. The 18-K experimental photoluminescence (PL) peak energy of the InGaPN/GaPN SQW on a GaP substrate, which was grown by radiofrequency plasma-assisted molecular-beam epitaxy (RF-MBE), was in good agreement with the calculated transition energy between the first electron quantum level and the first heavy-hole quantum level. The conduction band offsets of the InGaPN/GaPN SQW with N compositions of 1-2% into the InGaPN well grown on GaP substrates were several dozens meV at the most, while the valence band offsets were 200-300 meV due to compressive strain increased by increasing In compositions. Therefore, larger N compositions of the InGaPN well were required to increase the conduction band offsets of the InGaPN/GaPN SQW for light-emitting devices. It was demonstrated that the type-I InGaPN/GaPN SQW with a direct bandgap could be obtained on Si substrates. Our calculation results showed that the appropriate In composition of the InGaPN well were 30-45% and N composition of the GaPN barrier 1-2%. The differences of N compositions around 3% between the InGaPN well and the GaPN barrier were required for realizing a conduction band offset of 300 meV.

  11. TDRSS telecommunications system, PN code analysis

    NASA Technical Reports Server (NTRS)

    Dixon, R.; Gold, R.; Kaiser, F.

    1976-01-01

    The pseudo noise (PN) codes required to support the TDRSS telecommunications services are analyzed and the impact of alternate coding techniques on the user transponder equipment, the TDRSS equipment, and all factors that contribute to the acquisition and performance of these telecommunication services is assessed. Possible alternatives to the currently proposed hybrid FH/direct sequence acquisition procedures are considered and compared relative to acquisition time, implementation complexity, operational reliability, and cost. The hybrid FH/direct sequence technique is analyzed and rejected in favor of a recommended approach which minimizes acquisition time and user transponder complexity while maximizing probability of acquisition and overall link reliability.

  12. Electrostatic model of radial pn junction nanowires

    NASA Astrophysics Data System (ADS)

    Chia, A. C. E.; LaPierre, R. R.

    2013-08-01

    Poisson's equation is solved for a radial pn junction nanowire (NW) with surface depletion. This resulted in a model capable of giving radial energy band and electric field profiles for any arbitrary core/shell doping density, core/shell dimensions, and surface state density. Specific cases were analyzed to extract pertinent underlying physics, while the relationship between NW specifications and the depletion of the NW were examined to optimize the built-in potential across the junction. Additionally, the model results were compared with experimental results in literature to good agreement. Finally, an optimum device design is proposed to satisfy material, optical, and electrostatic constraints in high efficiency NW solar cells.

  13. Radial pn Junction, Wire Array Solar Cells

    NASA Astrophysics Data System (ADS)

    Kayes, Brendan Melville

    Radial pn junctions are potentially of interest in photovoltaics as a way to decouple light absorption from minority carrier collection. In a traditional planar design these occur in the same dimension, and this sets a lower limit on absorber material quality, as cells must both be thick enough to effectively absorb the solar spectrum while also having minority-carrier diffusion lengths long enough to allow for efficient collection of the photo-generated carriers. Therefore, highly efficient photovoltaic devices currently require highly pure materials and expensive processing techniques, while low cost devices generally operate at relatively low efficiency. The radial pn junction design sets the direction of light absorption perpendicular to the direction of minority-carrier transport, allowing the cell to be thick enough for effective light absorption, while also providing a short pathway for carrier collection. This is achieved by increasing the junction area, in order to decrease the path length any photogenerated minority carrier must travel, to be less than its minority carrier diffusion length. Realizing this geometry in an array of semiconducting wires, by for example depositing a single-crystalline inorganic semiconducting absorber layer at high deposition rates from the gas phase by the vapor-liquid-solid (VLS) mechanism, allows for a "bottom up" approach to device fabrication, which can in principle dramatically reduce the materials costs associated with a cell.

  14. Spectroscopy of two PN candidates in IC10

    NASA Astrophysics Data System (ADS)

    Kniazev, A. Y.; Pustilnik, S. A.; Zucker, D. B.

    2008-03-01

    We present the results of the first spectroscopic observations of two planetary nebula (PN) candidates in the Local Group dwarf irregular galaxy IC10. Using several spectral classification diagrams, we show that the brightest PN candidate (PN7) is not a PN, but rather a compact HII region consisting of two components with low electron number densities. After the rejection of this PN candidate, the IC10 PN luminosity function cut-off becomes very close to the standard value. With the compiled spectroscopic data for a large number of extragalactic PNe, we analyse a series of diagnostic diagrams to generate quantitative criteria for separating PNe from unresolved HII regions. We show that, with the help of the diagnostic diagrams and the derived set of criteria, PNe can be distinguished from HII regions with an efficiency of ~99.6 per cent. With the obtained spectroscopic data, we confirm that another, 1.7 mag fainter PN candidate (PN9) is a genuine PN. We argue that, based on all currently available PNe data, IC10 is located at a distance of 725+63-33 kpc [distance modulus (m - M) = 24.30+0.18-0.10]. Based on observations obtained at the 6-m SAO RAS (Special Astrophysical Observatory of Russian Academy of Science) telescope. E-mail: akniazev@saao.ac.za (AYK); sap@sao.ru (SAP); zucker@ast.cam.ac.uk (DBZ)

  15. Mapping Pn amplitude spreading and attenuation in Asia

    SciTech Connect

    Yang, Xiaoning; Phillips, William S; Stead, Richard J

    2010-12-06

    Pn travels most of its path in the mantle lid. Mapping the lateral variation of Pn amplitude attenuation sheds light on material properties and dynamics of the uppermost region of the mantle. Pn amplitude variation depends on the wavefront geometric spreading as well as material attenuation. We investigated Pn geometric spreading, which is much more complex than a traditionally assumed power-law spreading model, using both synthetic and observed amplitude data collected in Asia. We derived a new Pn spreading model based on the formulation that was proposed previously to account for the spherical shape of the Earth (Yang et. al., BSSA, 2007). New parameters derived for the spreading model provide much better correction for Pn amplitudes in terms of residual behavior. Because we used observed Pn amplitudes to construct the model, the model incorporates not only the effect of the Earth's spherical shape, but also the effect of potential upper-mantle velocity gradients in the region. Using the new spreading model, we corrected Pn amplitudes measured at 1, 2, 4 and 6 Hz and conducted attenuation tomography. The resulting Pn attenuation model correlates well with the regional geology. We see high attenuation in regions such as northern Tibetan Plateau and the western Pacific subduction zone, and low attenuation for stable blocks such as Sichuan and Tarim basins.

  16. Measurement of χcj decaying into pn̄π⁻ and pn̄π⁻π⁰

    DOE PAGESBeta

    Ablikim, M.; Achasov, M. N.; Albayrak, O.; Ambrose, D. J.; An, F. F.; An, Q.; Bai, J. Z.; Ban, Y.; Becker, J.; Bennett, J. V.; et al

    2012-09-26

    Using a data sample of 1.06×10⁸ ψ' events collected with the BESIII detector in 2009, the branching fractions of χcJ→pn̄π⁻ and χcJ→pn̄π⁻π⁰ (J=0, 1, 2) are measured. (Throughout the text, inclusion of charge conjugate modes is implied if not stated otherwise.) The results for χc⁰→pn̄π⁻ and χc²→pn̄π⁻ are consistent with, but much more precise than, those of previous measurements. The decays of χc1→pn̄π⁻ and χcJ→pn̄π⁻π⁰ are observed for the first time.

  17. Novel pneumoviruses (PnVs): Evolution and inflammatory pathology

    SciTech Connect

    Glineur, Stephanie F.; Renshaw, Randall W.; Percopo, Caroline M.; Dyer, Kimberly D.; Dubovi, Edward J.; Domachowske, Joseph B.; Rosenberg, Helene F.

    2013-09-01

    A previous report of a novel pneumovirus (PnV) isolated from the respiratory tract of a dog described its significant homology to the rodent pathogen, pneumonia virus of mice (PVM). The original PnV–Ane4 pathogen replicated in and could be re-isolated in infectious state from mouse lung but elicited minimal mortality compared to PVM strain J3666. Here we assess phylogeny and physiologic responses to 10 new PnV isolates. The G/glycoprotein sequences of all PnVs include elongated amino-termini when compared to the characterized PVMs, and suggest division into groups A and B. While we observed significant differences in cytokine production and neutrophil recruitment to the lungs of BALB/c mice in response to survival doses (50 TCID{sub 50} units) of representative group A (114378-10-29-KY-F) and group B (7968-11-OK) PnVs, we observed no evidence for positive selection (dN>dS) among the PnV/PnV, PVM/PnV or PVM/PVM G/glycoprotein or F/fusion protein sequence pairs. - Highlights: • We consider ten novel isolates of the pneumovirus (PnV) first described by Renshaw and colleagues. • The G/glycoprotein sequences of all PnVs include elongated amino-termini when compared to PVM. • We detect cytokine production and neutrophil recruitment to the lungs of mice in response to PnV. • We observed no evidence for positive selection (dN>dS) among the gene sequence pairs.

  18. Studies of silicon PN junction solar cells

    NASA Technical Reports Server (NTRS)

    Lindholm, F. A.

    1975-01-01

    Silicon pn junction solar cells made with low-resistivity substrates show poorer performance than traditional theory predicts. The purpose of this research was to identify and characterize the physical mechanisms responsible for the discrepancy. Attention was concentrated on the open circuit voltage in shallow junction cells of 0.1 ohm-cm substrate resistivity. A number of possible mechanisms that can occur in silicon devices were considered. Two mechanisms which are likely to be of main importance in explaining the observed low values of open-circuit voltage were found: (1) recombination losses associated with defects introduced during junction formation, and (2) inhomogeneity of defects and impurities across the area of the cell. To explore these theoretical anticipations, various diode test structures were designed and fabricated and measurement configurations for characterizing the defect properties and the areal inhomogeneity were constructed.

  19. Electronic Veselago lensing in graphene PN junctions

    NASA Astrophysics Data System (ADS)

    Dean, Cory

    Ballistic electrons in a uniform 2D electron gas (2DEG) behave in close analogy to light propagating through an optical medium. In the absence of impurity scattering, electrons follow straight-line trajectories, while the associated de Broglie wavelength can give rise to interference and diffraction. Here we present measurements of ballistic graphene devices in which a graphite gate is used to realize an atomically-smooth junction. We demonstrate unambiguous signatures of negative refraction across a PN junction, paving the way for electron optics inspired by Veselago lensing. Comparison with theoretical simulations reveals the importance of the junction profile towards this effort. Opportunities for future device designs that may take advantage of these effects will be discussed.

  20. Field-effect P-N junction

    DOEpatents

    Regan, William; Zettl, Alexander

    2015-05-05

    This disclosure provides systems, methods, and apparatus related to field-effect p-n junctions. In one aspect, a device includes an ohmic contact, a semiconductor layer disposed on the ohmic contact, at least one rectifying contact disposed on the semiconductor layer, a gate including a layer disposed on the at least one rectifying contact and the semiconductor layer and a gate contact disposed on the layer. A lateral width of the rectifying contact is less than a semiconductor depletion width of the semiconductor layer. The gate contact is electrically connected to the ohmic contact to create a self-gating feedback loop that is configured to maintain a gate electric field of the gate.

  1. Photoelectron multipliers based on avalanche pn — i — pn structures

    NASA Astrophysics Data System (ADS)

    Lukin, K. A.; Maksymov, P. P.; Cerdeira, H. A.

    2014-12-01

    We present a new physical principle to design an optoelectronic device, which consists of a multilayered semiconductor structure, where the necessary conditions for generation of photoelectrons are met, such that it will enable sequential avalanche multiplication of electrons and holes inside two depletion slabs created around the p - n junctions of a reverse biased pn - i - pn structure. The mathematical model and computer simulations of this Semiconductor Photo-electron Multiplier (SPEM) for different semiconductor materials are presented. Its performance is evaluated and compared with that of conventional devices. The Geiger operational mode is briefly discussed which may be used in Silicon Photomultiplier (SiPM) as an elementary photo detector to enhance its performance.

  2. Single P-N junction tandem photovoltaic device

    SciTech Connect

    Walukiewicz, Wladyslaw; Ager, III, Joel W.; Yu, Kin Man

    2011-10-18

    A single P-N junction solar cell is provided having two depletion regions for charge separation while allowing the electrons and holes to recombine such that the voltages associated with both depletion regions of the solar cell will add together. The single p-n junction solar cell includes an alloy of either InGaN or InAlN formed on one side of the P-N junction with Si formed on the other side in order to produce characteristics of a two junction (2J) tandem solar cell through only a single P-N junction. A single P-N junction solar cell having tandem solar cell characteristics will achieve power conversion efficiencies exceeding 30%.

  3. Single P-N junction tandem photovoltaic device

    SciTech Connect

    Walukiewicz, Wladyslaw; Ager, III, Joel W.; Yu, Kin Man

    2012-03-06

    A single P-N junction solar cell is provided having two depletion regions for charge separation while allowing the electrons and holes to recombine such that the voltages associated with both depletion regions of the solar cell will add together. The single p-n junction solar cell includes an alloy of either InGaN or InAlN formed on one side of the P-N junction with Si formed on the other side in order to produce characteristics of a two junction (2J) tandem solar cell through only a single P-N junction. A single P-N junction solar cell having tandem solar cell characteristics will achieve power conversion efficiencies exceeding 30%.

  4. Radio frequency interference effect on PN code sequence lock detector

    NASA Technical Reports Server (NTRS)

    Kwon, Hyuck M.; Tu, Kwei; Loh, Y. C.

    1991-01-01

    The authors find the probabilities of detection and false alarm of the pseudonoise (PN) sequence code lock detector when strong radio frequency interference (RFI) hits the communications link. Both a linear model and a soft-limiter nonlinear model for a transponder receiver are considered. In addition, both continuous wave (CW) RFI and pulse RFI are analyzed, and a discussion is included of how strong CW RFI can knock out the PN code lock detector in a linear or a soft-limiter transponder. As an example, the Space Station Freedom forward S-band PN system is evaluated. It is shown that a soft-limiter transponder can protect the PN code lock detector against a typical pulse RFI, but it can degrade the PN code lock detector performance more than a linear transponder if CW RFI hits the link.

  5. Optimum waiting time for acquisition of return link PN signals

    NASA Technical Reports Server (NTRS)

    Kolata, W.

    1982-01-01

    The subject of this paper is a model that takes into account the effect that acquisition of a PN signal on the forward link has on the acquisition of a PN signal on the return link. The model is used to determine how long the start of the PN search on the return link should be delayed in order to minimize the combined acquisition time (delay + acquisition time) as a function of desired acquisition probability. It is assumed that the return link a-priori epoch uncertainty information is available. Software has been developed that models the return link PN receiver and incorporates in it the effect of forward link PN acquisition statistics in assessing performance.

  6. Pn anisotropic tomography and mantle dynamics beneath China

    NASA Astrophysics Data System (ADS)

    Zhou, Zhigang; Lei, Jianshe

    2016-08-01

    We present a new high-resolution Pn anisotropic tomographic model of the uppermost mantle beneath China inferred from 52,061 Pn arrival-time data manually picked from seismograms recorded at provincial seismic stations in China and temporary stations in Tibet and the Tienshan orogenic belt. Significant features well correlated with surface geology are revealed and provide new insights into the deep dynamics beneath China. Prominent high Pn velocities are visible under the stable cratonic blocks (e.g., the Tarim, Junngar, and Sichuan basins, and the Ordos block), whereas remarkable low Pn velocities are observed in the tectonically active areas (e.g., Pamir, the Tienshan orogenic belt, central Tibet and the Qilian fold belt). A distinct N-S trending low Pn velocity zone around 86°E is revealed under the rift running from the Himalayan block through the Lhasa block to the Qiangtang block, which indicates the hot material upwelling due to the breaking-off of the subducting Indian slab. Two N-S trending low Pn velocity belts with an approximate N-S Pn fast direction along the faults around the Chuan-Dian diamond block suggest that these faults may serve as channels of mantle flow from Tibet. The fast Pn direction changes from N-S in the north across 27°N to E-W in the south, which may reflect different types of mantle deformation. The anisotropy in the south could be caused by the asthenospheric flow resulted from the eastward subduction of the Indian plate down to the mantle transition zone beneath the Burma arc. Across the Talas-Fergana fault in the Tienshan orogenic belt, an obvious difference in velocity and anisotropy is revealed. To the west, high Pn velocities and an arc-shaped fast Pn direction are observed, implying the Indo-Asian collision, whereas to the east low Pn velocities and a range-parallel Pn fast direction are imaged, reflecting the northward underthrusting of the Tarim lithosphere and the southward underthrusting of the Kazakh lithosphere. In

  7. PN velocity beneath Western New Mexico and Eastern Arizona

    NASA Technical Reports Server (NTRS)

    Jaksha, L. H.

    1985-01-01

    The experiment involved observing Pn arrivals on an areal array of 7 seismic stations located in the transition zone and along the Jemez lineament. Explosions in coal and copper mines in New Mexico and Arizona were used as energy sources as well as military detonations at White Sands Missile Range, New Mexico, Yuma, Arizona, and the Nevada Test Site. Very preliminary results suggest a Pn velocity of 7.94 km/s (with a fairly large uncertainty) beneath the study area. The Pn delay times, which can be converted to estimates of crustal thickness given knowledge of the velocity structure of the crust increase both to the north and east of Springerville, Arizona. As a constraint on the velocity of Pn, researchers analyzed the reversed refraction line GNOME-HARDHAT which passes through Springerville oriented NW to SE. This analysis resulted in a Pn velocity of 7.9-8.0 km/s for the transition zone. These preliminary results suggest that a normal Pn velocity might persist even though the crust thins (from north to south) by 15 km along the length of the Arizona-New Mexico border. If the upper mantle is currently hot anywhere in western New Mexico or eastern Arizona then the dimensions of the heat source (or sources) might be small compared to the intra-station distances of the seismic arrays used to estimate the velocity of Pn.

  8. PN velocity beneath Western New Mexico and Eastern Arizona

    NASA Astrophysics Data System (ADS)

    Jaksha, L. H.

    The experiment involved observing Pn arrivals on an areal array of 7 seismic stations located in the transition zone and along the Jemez lineament. Explosions in coal and copper mines in New Mexico and Arizona were used as energy sources as well as military detonations at White Sands Missile Range, New Mexico, Yuma, Arizona, and the Nevada Test Site. Very preliminary results suggest a Pn velocity of 7.94 km/s (with a fairly large uncertainty) beneath the study area. The Pn delay times, which can be converted to estimates of crustal thickness given knowledge of the velocity structure of the crust increase both to the north and east of Springerville, Arizona. As a constraint on the velocity of Pn, researchers analyzed the reversed refraction line GNOME-HARDHAT which passes through Springerville oriented NW to SE. This analysis resulted in a Pn velocity of 7.9-8.0 km/s for the transition zone. These preliminary results suggest that a normal Pn velocity might persist even though the crust thins (from north to south) by 15 km along the length of the Arizona-New Mexico border. If the upper mantle is currently hot anywhere in western New Mexico or eastern Arizona then the dimensions of the heat source (or sources) might be small compared to the intra-station distances of the seismic arrays used to estimate the velocity of Pn.

  9. Photoinduced carrier annihilation in silicon pn junction

    NASA Astrophysics Data System (ADS)

    Sameshima, Toshiyuki; Motoki, Takayuki; Yasuda, Keisuke; Nakamura, Tomohiko; Hasumi, Masahiko; Mizuno, Toshihisa

    2015-08-01

    We report analysis of the photo-induced minority carrier effective lifetime (τeff) in a p+n junction formed on the top surfaces of a n-type silicon substrate by ion implantation of boron and phosphorus atoms at the top and bottom surfaces followed by activation by microwave heating. Bias voltages were applied to the p+ boron-doped surface with n+ phosphorus-doped surface kept at 0 V. The values of τeff were lower than 1 × 10-5 s under the reverse-bias condition. On the other hand, τeff markedly increased to 1.4 × 10-4 s as the forward-bias voltage increased to 0.7 V and then it leveled off when continuous-wave 635 nm light was illuminated at 0.74 mW/cm2 on the p+ surface. The carrier annihilation velocity S\\text{p + } at the p+ surface region was numerically estimated from the experimental τeff. S\\text{p + } ranged from 4000 to 7200 cm/s under the reverse-bias condition when the carrier annihilation velocity S\\text{n + } at the n+ surface region was assumed to be a constant value of 100 cm/s. S\\text{p + } markedly decreased to 265 cm/s as the forward-bias voltage increased to 0.7 V.

  10. Analytical modeling of the radial pn junction nanowire solar cells

    NASA Astrophysics Data System (ADS)

    Ali, Nouran M.; Allam, Nageh K.; Abdel Haleem, Ashraf M.; Rafat, Nadia H.

    2014-07-01

    In photovoltaic solar cells, radial p-n junctions have been considered a very promising structure to improve the carrier collection efficiency and accordingly the conversion efficiency. In the present study, the semiconductor equations, namely Poisson's and continuity equations for a cylindrical p-n junction solar cell, have been solved analytically. The analytical model is based on Green's function theory to calculate the current density, open circuit voltage, fill factor, and conversion efficiency. The model has been used to simulate p-n and p-i-n silicon radial solar cells. The validity and accuracy of the present simulator were confirmed through a comparison with previously published experimental and numerical reports.

  11. P(N) approximation for frequency-domain measurements in scattering media.

    PubMed

    Faris, Gregory W

    2005-04-10

    Presented here are expressions for the P(N) approximation for light propagation in scattering media in the frequency domain. To elucidate parametric dependencies, the derivation uses normalization of the resulting expressions to either the total interaction coefficient or the reduced total interaction coefficient. For the latter case, a set of reduced phase function coefficients are introduced. Expression of the P(N) approximation as a conventional eigenvalue problem facilitates computation of the eigenvalues or attenuation coefficients. This approach is used to determine the attenuation coefficients in the asymptotic regime over the full values of the scattering albedo and reduced scattering albedo (0 to 1) and all positive values of the asymmetry factor (0 to 1). Frequency-domain measurements yield a sensitivity to turbid media optical properties for reduced scattering albedos as small as 0.2. P(N) calculations are used to assess the magnitude of errors associated with the P1 and P3 approximations over a range of scattering albedo, phase function, and modulation frequency. PMID:15835355

  12. Analytical theory of the space-charge region of lateral p-n junctions in nanofilms

    SciTech Connect

    Gurugubelli, Vijaya Kumar Karmalkar, Shreepad

    2015-07-21

    There is growing interest in fabricating conventional semiconductor devices in a nanofilm which could be a 3D material with one reduced dimension (e.g., silicon-on-insulator (SOI) film), or single/multiple layers of a 2D material (e.g., MoS{sub 2}), or a two dimensional electron gas/two dimensional hole gas (2DEG/2DHG) layer. Lateral p-n junctions are essential parts of these devices. The space-charge region electrostatics in these nanofilm junctions is strongly affected by the surrounding field, unlike in bulk junctions. Current device physics of nanofilms lacks a simple analytical theory of this 2D electrostatics of lateral p-n junctions. We present such a theory taking into account the film's thickness, permittivity, doping, interface charge, and possibly different ambient permittivities on film's either side. In analogy to the textbook theory of the 1D electrostatics of bulk p-n junctions, our theory yields simple formulas for the depletion width, the extent of space-charge tails beyond this width, and the screening length associated with the space-charge layer in nanofilm junctions; these formulas agree with numerical simulations and measurements. Our theory introduces an electrostatic thickness index to classify nanofilms into sheets, bulk and intermediate sized.

  13. Array analysis of regional Pn and Pg wavefields from the Nevada Test Site

    SciTech Connect

    Leonard, M.A. . Dept. of Geology and Geophysics Lawrence Berkeley Lab., CA )

    1991-06-01

    Small-aperture high-frequency seismic arrays with dimensions of a few kilometers or less, can improve our ability to seismically monitor compliance with a low-yield Threshold Test Ban Treaty. This work studies the characteristics and effectiveness of array processing of the regional Pn and Pg wavefields generated by underground nuclear explosions at the Nevada Test Site. Waveform data from the explosion HARDIN (m{sub b} = 5.5) is recorded at a temporary 12-element, 3-component, 1.5 km-aperture array sited in an area of northern Nevada. The explosions VILLE (m{sub b} = 4.4) and SALUT (m{sub b} = 5.5) are recorded at two arrays sited in the Mojave desert, one a 96-element vertical-component 7 km-aperture array and the other a 155-element vertical-component 4 km-aperture array. Among the mean spectra for the m{sub b} = 5.5 events there are significant differences in low-frequency spectral amplitudes between array sites. The spectra become nearly identical beyond about 6 Hz. Spectral ratios are used to examine seismic source properties and the partitioning of energy between Pn and Pg. Frequency-wavenumber analysis at the 12-element array is used to obtain estimates of signal gain, phase velocity, and source azimuth. This analysis reveals frequency-dependent biases in velocity and azimuth of the coherent Pn and Pg arrivals. Signal correlation, the principal factor governing array performance, is examined in terms of spatial coherence estimates. The coherence is found to vary between the three sites. In all cases the coherence of Pn is greater than that for Pg. 81 refs., 92 figs., 5 tabs.

  14. Hybrid pn-junction solar cells based on layers of inorganic nanocrystals and organic semiconductors: optimization of layer thickness by considering the width of the depletion region.

    PubMed

    Saha, Sudip K; Guchhait, Asim; Pal, Amlan J

    2014-03-01

    We report the formation and characterization of hybrid pn-junction solar cells based on a layer of copper diffused silver indium disulfide (AgInS2@Cu) nanoparticles and another layer of copper phthalocyanine (CuPc) molecules. With copper diffusion in the nanocrystals, their optical absorption and hence the activity of the hybrid pn-junction solar cells was extended towards the near-IR region. To decrease the particle-to-particle separation for improved carrier transport through the inorganic layer, we replaced the long-chain ligands of copper-diffused nanocrystals in each monolayer with short-ones. Under illumination, the hybrid pn-junctions yielded a higher short-circuit current as compared to the combined contribution of the Schottky junctions based on the components. A wider depletion region at the interface between the two active layers in the pn-junction device as compared to that of the Schottky junctions has been considered to analyze the results. Capacitance-voltage characteristics under a dark condition supported such a hypothesis. We also determined the width of the depletion region in the two layers separately so that a pn-junction could be formed with a tailored thickness of the two materials. Such a "fully-depleted" device resulted in an improved photovoltaic performance, primarily due to lessening of the internal resistance of the hybrid pn-junction solar cells. PMID:24452695

  15. Progress with PN-CCDs for the XMM satellite mission

    NASA Astrophysics Data System (ADS)

    Braeuninger, H.; Hauff, D.; Lechner, P.; Lutz, G.; Kink, W.; Meidinger, N.; Metzner, G.; Predehl, P.; Reppin, C.; Strueder, L.

    1991-10-01

    PN-CCDs are being developed as focal plane detectors for ESA's X-ray Multi-Mirror satellite mission (XMM), to be launched at the end of this century. As a part of the European Photon Imaging Camera (EPIC) the pn-CCDs will convert the incoming X-ray radiation with high quantum efficiency, low readout noise, excellent background rejection, timing in the microsec regime, radiation tolerance up to several hundreds of krads and a position resolution tailored according to the angular resolution of the telescope. The goal of our laboratorial efforts for this mission is to fabricate a monolithic pn-CCD of an active area of 6 x 6 sq cm having 768 on-chip JFET amplifiers located at the end of each CCD line. It is the aim of this contribution to report on the ongoing work of the pn-CCD system. This article focuses on the position resolution capabilities of fully depleted pn-CCDs, some recent results in the noise analysis and preliminary results on 10 MeV proton damage.

  16. Studies of silicon p-n junction solar cells

    NASA Technical Reports Server (NTRS)

    Neugroschel, A.; Lindholm, F. A.

    1979-01-01

    To provide theoretical support for investigating different ways to obtain high open-circuit voltages in p-n junction silicon solar cells, an analytical treatment of heavily doped transparent-emitter devices is presented that includes the effects of bandgap narrowing, Fermi-Dirac statistics, a doping concentration gradient, and a finite surface recombination velocity at the emitter surface. Topics covered include: (1) experimental determination of bandgap narrowing in the emitter of silicon p-n junction devices; (2) heavily doped transparent regions in junction solar cells, diodes, and transistors; (3) high-low-emitter solar cell; (4) determination of lifetimes and recombination currents in p-n junction solar cells; (5) MOS and oxide-charged-induced BSF solar cells; and (6) design of high efficiency solar cells for space and terrestrial applications.

  17. The XMM pn-CCD detector system: First results

    NASA Astrophysics Data System (ADS)

    Braeuninger, H.; Danner, R.; Findeis, N.; Hauff, D.; Holl, P.; Kemmer, J.; Kendziorra, E.; Kraemer, J.; Lechner, P.; Lutz, G.

    1992-12-01

    The pn-CCD (Charge Coupled Device) is a novel type of CCD developed for fast X-ray imaging and spectroscopy for the X-ray Multi Mirror (XMM) satellite mission. Each 200 by 64 pixel large pn-CCD unit with a sensitive area of 3 by 1 sq cm is a fully depleted detector. With the use of the CMOS Amplifier and Multiplexing chip (CAMEX64B) it is possible to read out the 64 CCD channels in parallel before they are multiplexed and sent to an ADC. For the first time the system of a 64 channel pn-CCD together with CAMEX64B readout, ADC conversion, and data acquisition and storage has been brought into operation. First images of an Fe-55 X-ray source are presented and discussed.

  18. Bounds on the Information Carrying Capacity of Pn Waves

    SciTech Connect

    Harris, D B

    2008-12-01

    Upper and lower bounds on the capacity of the Pn wave to transmit information about source identity are developed using models and measurements of Pn spatial signal structure across the ARCES array. The results show a very significant increase in information carrying capacity when contrasting observed propagation conditions with idealized free-space propagation. In essence, scattering greatly increases Pn channel capacity. As shown in a previous contribution, this increase in information can be captured with matched field calibrations and exploited to resolve sources more closely spaced than the Rayleigh resolution limit. These results mirror practices in cellular telephones that use arrays at the transmitter and receiver to exploit scattering for increased channel capacity.

  19. Pn Tomography of the Central and Eastern United States

    NASA Astrophysics Data System (ADS)

    Zhang, Q.; Sandvol, E. A.; Liu, M.

    2005-12-01

    Approximately 44,000 Pn phase readings from the ISC and NEIC catalogs and 750 hand picked arrivals were inverted to map the velocity structure of mantle lithosphere in the Central and Eastern United States (CEUS). Overall we have a high density of ray paths within the active seismic zones in the eastern and southern parts of the CEUS, while ray coverage is relatively poor to the west of Great Lakes as well as along the eastern and southern coastlines of the U.S. The average Pn velocity in the CEUS is approximately 8.03 km/s. High Pn velocities (~8.18 km/s) within the northeastern part of the North American shield are reliable, while the resolution of the velocity image of the American shield around the mid-continent rift (MCR) is relatively low due to the poor ray coverage. Under the East Continent Rift (EC), the northern part of the Reelfoot Rift Zone (RRZ), and the South Oklahoma Aulacogen (SO), we also observe high velocity lithospheric mantle (~8.13-8.18 km/s). Typical Pn velocities (~7.98 km/s) are found between those three high velocity blocks. Low velocities are shown in the northern and southern Appalachians (~7.88-7.98 km/s) as well as the Rio Grande Rift (~7.88 km/s). In the portion of our model with the highest ray density, the Pn azimuthal anisotropy seems to be robust. These fast directions appear to mirror the boundaries of the low Pn velocity zone and parallel the Appalachians down to the southwest.

  20. The 'depletion layer' of amorphous p-n junctions

    NASA Technical Reports Server (NTRS)

    Von Roos, O.

    1981-01-01

    It is shown that within reasonable approximations for the density of state distribution within the mobility gap of a:Si, a one-to-one correspondence exists between the electric field distribution in the transition region of an amorphous p-n junction and that in the depletion layer of a crystalline p-n junction. Thus it is inferred that the depletion layer approximation which leads to a parabolic potential distribution within the depletion layer of crystalline junctions also constitutes a fair approximation in the case of amorphous junctions. This fact greatly simplifies an analysis of solid-state electronic devices based on amorphous material (i.e., solar cells).

  1. The Oklahoma PN/ADN Articulation Project Report.

    ERIC Educational Resources Information Center

    Oklahoma State Regents for Higher Education, Oklahoma City.

    In response to a critical nursing shortage in the state of Oklahoma, the Oklahoma Practical Nursing (PN)/Associate Degree Nursing (ADN) Articulation Project Coordinating Committee was formed in spring 1990 to develop a proposal for program articulation. A curriculum matrix was designed and adopted for use by five regional subcommittees which…

  2. Improving detection range via correlation of long PN codes

    NASA Astrophysics Data System (ADS)

    Subedi, Saurav; Wang, Zhonghai; Zheng, Y. Rosa

    2012-06-01

    This paper proposes a correlation method for detecting super-regenerative RF receivers via stimulation. Long PN sequences are used as to stimulate the unintended emissions from the RF receivers. High correlation between known PN sequence and stimulated unintended emissions from RF receivers helps improving the detection range compared to passive detection and power detection methods. Although RF receivers generate unintended emissions from their nonlinear devices, without stimulation, the power of these unintended emission is usually lower than --70dBm, as per the FCC regulations. Direct detection (passive detection) of these emissions is a challenging task specially in noisy conditions. When a stimulation signal is transmitted from distance, superregenerative receivers generate unintended emissions that contain the stimulation signal and its harmonics. Excellent correlation property of PN sequence enables us to improve the range and accuracy of detecting the super-regenerative receivers through stimulation method even in noisy conditions. The experiment involves detection of wireless doorbell, a commercially available super-regenerative receiver. USRP is used for transmitting the stimulant signal and receiving unintended stimulated emissions from the doorbell. Experiments show that the detection range of the proposed method with long PN sequences is much larger than passive detection and power detection methods.

  3. What Can Be Learned from X-Ray Spectroscopy Concerning Hot Gas in the Local Bubble and Charge Exchange Processes?

    NASA Technical Reports Server (NTRS)

    Snowden, S. L.

    2008-01-01

    Both solar wind charge exchange emission and diffuse thermal emission from the Local Bubble are strongly dominated in the soft X-ray band by lines from highly ionized elements. While both processes share many of the same lines, the spectra should differ significantly due to the different production mechanisms, abundances, and ionization states. Despite their distinct spectral signatures, current and past observatories have lacked the spectral resolution to adequately distinguish between the two sources. High-resolution X-ray spectroscopy instrumentation proposed for future missions has the potential to answer fundamental questions such as whether there is any hot plasma in the Local Hot Bubble, and if so, what are the abundances of the emitting plasma and whether the plasma is in equilibrium. Such instrumentation will provide dynamic information about the solar wind including data on ion species which are currently difficult to track. It will also make possible remote sensing of the solar wind.

  4. What can be Learned from X-Ray Spectroscopy Concerning Hot Gas in the Local Bubble and Charge Exchange Processes

    NASA Technical Reports Server (NTRS)

    Snowden, Steven L.

    2007-01-01

    Solar wind charge exchange produces diffuse X-ray emission with a variable surface brightness comparable to that of the cosmic background. While the temporal variation of the charge exchange emission allows some separation of the components, there remains a great deal of uncertainty as to the zero level of both. Because the production mechanisms of the two components are considerably different, their spectra would provide critical diagnostics to the understanding of both. However, current X-ray observatories are very limited in both spectral resolution and sensitivity in the critical soft X-ray (less than 1.0 keV) energy range. Non-dispersive high-resolution spectrometers, such as the calorimeter proposed for the Spectrum Roentgen Gamma mission, will be extremely useful in distinguishing the cascade emission of charge exchange from the spectra of thermal bremsstrahlung cosmic plasmas.

  5. SMARTS Thermal Architecture for PnPSat-2

    NASA Astrophysics Data System (ADS)

    Bugby, D. C.; Zimbeck, W. R.; Preble, J. C.; Kroliczek, E. J.

    2010-01-01

    This paper describes an integrated thermal-mechanical architecture for responsive small satellites that combines the intrinsic thermal management capabilities of the Satellite Modular and Reconfigurable Thermal System (SMARTS) with the modular, quick assembly mechanical design offered by the Plug-and-Play Satellite-2 (PnPSat-2) structure. PnPSat-2 is the second generation Plug and Play satellite bus. SMARTS and PnPSat-2 are technology development programs funded by the Air Force Research Laboratory (AFRL) Space Vehicles Directorate at Kirtland AFB, NM. To meet the three-tiered responsive space needs of the DoD, varying levels of responsiveness from immediate (Tier 1), to days (Tier 2), to months (Tier 3) are needed. SMARTS offers an intrinsic thermal solution that combines a multi-heat pipe isothermal bus, oversized body-mounted radiators, a bus-to-radiator loop heat pipe (LHP) thermal transport/switching system, and maximum external insulation. PnPSat-2 offers an intrinsic mechanical solution that includes panels with embedded electronics, multiple component mounting locations, and features that allow the spacecraft to be transitioned to a flat-sat for easy assembly, integration, de-integration, and reassembly. To combine the two architectures, internal half-panels were redesigned to include spreader heat pipes (SHPs) for intra-panel isothermalization, side-to-top panel structural brackets were replaced by a combined bracket-header heat pipe (HHP) for inter-panel isothermalization, and an LHP evaporator was mounted to the HHP to enable variable conductance between the isothermal spacecraft bus and body-mounted (condensers) radiators. To evaluate the concept, a three-panel thermal test bed will be configured to simulate the combined SMARTS/PnPSat-2 configuration. The paper will describe the system design, key analytical trades, hardware status, and available test data.

  6. Narrow-band light emission from a single carbon nanotube p-n diode

    NASA Astrophysics Data System (ADS)

    Kinoshita, Megumi; Mueller, Thomas; Steiner, Mathias; Perebeinos, Vasili; Bol, Ageeth; Farmer, Damon; Avouris, Phaedon

    2010-03-01

    We present the first observation of electroluminescence from electrostatically-generated carbon nanotube (CNT) p-n junctions[1]. While CNT optoelectronics has made much progress in recent years, observations of emission from electrically excited CNT devices have been limited to the high-bias regime and with low efficiency. Furthermore, the resulting broad linewidths are broad, making it difficult to investigate electronic levels and carrier dynamics. We find that p-n junctions allow for better carrier control at lower power inputs, resulting in emission with near-zero threshold, low self-heating and efficiency two to three orders of magnitude greater compared to previous device configurations. This yields higher signal-to-noise ratio and narrower linewidths (down to ˜35 meV) that allows us to identify localized excitonic transitions that have previously been observed only in photoluminescent studies. [1] T. Mueller, M. Kinoshita, M. Steiner, V. Perebeinos, A. Bol, D. Farmer, and Ph. Avouris, Nature Nanotech., web publication, November 15 2009.

  7. Tc-99m complexes of new functionalized propylene amine oxime (PnAO) ligands

    SciTech Connect

    Pillai, M.R.A.; Kothari, K.; Ramamoorthy, N.

    1994-05-01

    Three new functionalized PnAO ligands, 3,3,9,9-tetra-methyl-6-R-4, 8-diazaundecane-2,10-dionedioxime (R=benzyl, p-nitrobenzyl and p-aminobenzyl) were synthesised. Tc-99m complexes of these ligands were prepared by direct reduction of Tc-99m O{sub 4}{sup -} using stannous tartrate in the presence of ligands at pH 9.0. Complexation yields were greater than 95% at 1h and 24h post preparation as assessed by ITLC, HPLC and extraction into CHCl3. All three of the complexes were neutral and lipophilic (logP > 2.0) and eluted as single peak from a RP HPLC column. Biodistribution studies of the Tc-99m complexes of the benzyl and the nitrobenzyl derivatives were done in Wistar rats. Both complexes showed brain uptake but were washed out of the brain similar to the behavior of Tc-99m PnAO.

  8. The Involvement of Protease Nexin-1 (PN1) in the Pathogenesis of Intervertebral Disc (IVD) Degeneration

    PubMed Central

    Wu, Xinghuo; Liu, Wei; Duan, Zhenfeng; Gao, Yong; Li, Shuai; Wang, Kun; Song, Yu; Shao, Zengwu; Yang, Shuhua; Yang, Cao

    2016-01-01

    Protease nexin-1 (PN-1) is a serine protease inhibitor belonging to the serpin superfamily. This study was undertaken to investigate the regulatory role of PN-1 in the pathogenesis of intervertebral disk (IVD) degeneration. Expression of PN-1 was detected in human IVD tissue of varying grades. Expression of both PN-1 mRNA and protein was significantly decreased in degenerated IVD, and the expression levels of PN-1 were correlated with the grade of disc degeneration. Moreover, a decrease in PN-1 expression in primary NP cells was confirmed. On induction by IL-1β, the expression of PN-1 in NP cells was decreased at day 7, 14, and 21, as shown by western blot analysis and immunofluorescence staining. PN-1 administration decreased IL-1β-induced MMPs and ADAMTS production and the loss of Agg and Col II in NP cell cultures through the ERK1/2/NF-kB signaling pathway. The changes in PN-1 expression are involved in the pathogenesis of IVD degeneration. Our findings indicate that PN-1 administration could antagonize IL-1β-induced MMPs and ADAMTS, potentially preventing degeneration of IVD tissue. This study also revealed new insights into the regulation of PN-1 expression via the ERK1/2/NF-kB signaling pathway and the role of PN-1 in the pathogenesis of IVD degeneration. PMID:27460424

  9. Lipid emulsions containing fish oil protect against PN-induced cholestatic liver disease in preterm piglets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During their first weeks of life preterm infants are dependent on parenteral nutrition (PN). However, PN is associated with the development of cholestasis (PN Associated Liver Disease PNALD). Studies in children showed that fish oil-based lipid emulsions can reverse PNALD; whether they prevent PNALD...

  10. Measurement of χcj decaying into pn̄π⁻ and pn̄π⁻π⁰

    SciTech Connect

    Ablikim, M.; Achasov, M. N.; Albayrak, O.; Ambrose, D. J.; An, F. F.; An, Q.; Bai, J. Z.; Ban, Y.; Becker, J.; Bennett, J. V.; Bertani, M.; Bian, J. M.; Boger, E.; Bondarenko, O.; Boyko, I.; Briere, R. A.; Bytev, V.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, X.; Chen, Y. B.; Cheng, H. P.; Chu, Y. P.; Cronin-Hennessy, D.; Dai, H. L.; Dai, J. P.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; Ding, W. M.; Ding, Y.; Dong, L. Y.; Dong, M. Y.; Du, S. X.; Fang, J.; Fang, S. S.; Fava, L.; Feldbauer, F.; Feng, C. Q.; Ferroli, R. B.; Fu, C. D.; Fu, J. L.; Gao, Y.; Geng, C.; Goetzen, K.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, Y. P.; Han, Y. L.; Harris, F. A.; He, K. L.; He, M.; He, Z. Y.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, H. M.; Hu, T.; Huang, G. M.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, Y. P.; Hussain, T.; Ji, C. S.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. L.; Jiang, X. S.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Jing, F. F.; Kalantar-Nayestanaki, N.; Kavatsyuk, M.; Kuehn, W.; Lai, W.; Lange, J. S.; Li, C. H.; Li, Cheng; Li, Cui; Li, D. M.; Li, F.; Li, G.; Li, H. B.; Li, J. C.; Li, K.; Li, Lei; Li, Q. J.; Li, S. L.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, X. R.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Liao, X. T.; Liu, B. J.; Liu, C. L.; Liu, C. X.; Liu, C. Y.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H.; Liu, H. H.; Liu, H. M.; Liu, H. W.; Liu, J. P.; Liu, K. Y.; Liu, Kai; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqiang; Liu, Zhiqing; Loehner, H.; Lu, G. R.; Lu, H. J.; Lu, J. G.; Lu, Q. W.; Lu, X. R.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lv, M.; Ma, C. L.; Ma, F. C.; Ma, H. L.; Ma, Q. M.; Ma, S.; Ma, T.; Ma, X. Y.; Ma, Y.; Maas, F. E.; Maggiora, M.; Malik, Q. A.; Mao, Y. J.; Mao, Z. P.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Morales Morales, C.; Motzko, C.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nicholson, C.; Nikolaev, I. B.; Ning, Z.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Park, J. W.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Ping, J. L.; Ping, R. G.; Poling, R.; Prencipe, E.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, X. S.; Qin, Y.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Rong, G.; Ruan, X. D.; Sarantsev, A.; Schaefer, B. D.; Schulze, J.; Shao, M.; Shen, C. P.; Shen, X. Y.; Sheng, H. Y.; Shepherd, M. R.; Song, X. Y.; Spataro, S.; Spruck, B.; Sun, D. H.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Toth, D.; Ullrich, M.; Varner, G. S.; Wang, B.; Wang, B. Q.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, Q.; Wang, Q. J.; Wang, S. G.; Wang, X. L.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. Y.; Wei, D. H.; Wei, J. B.; Weidenkaff, P.; Wen, Q. G.; Wen, S. P.; Werner, M.; Wiedner, U.; Wu, L. H.; Wu, N.; Wu, S. X.; Wu, W.; Wu, Z.; Xia, L. G.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, G. M.; Xu, H.; Xu, Q. J.; Xu, X. P.; Xu, Z. R.; Xue, F.; Xue, Z.; Yan, L.; Yan, W. B.; Yan, Y. H.; Yang, H. X.; Yang, Y.; Yang, Y. X.; Ye, H.; Ye, M.; Ye, M. H.; Yu, B. X.; Yu, C. X.; Yu, H. W.; Yu, J. S.; Yu, S. P.; Yuan, C. Z.; Yuan, Y.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, S. H.; Zhang, X. J.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. S.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, H. S.; Zhao, J. W.; Zhao, K. X.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. Z.; Zhao, S. J.; Zhao, T. C.; Zhao, X. H.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, Y. H.; Zhong, B.; Zhong, J.; Zhong, Z.; Zhou, L.; Zhou, X. K.; Zhou, X. R.; Zhu, C.; Zhu, K.; Zhu, K. J.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. M.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zou, B. S.; Zou, J. H.

    2012-09-26

    Using a data sample of 1.06×10⁸ ψ' events collected with the BESIII detector in 2009, the branching fractions of χcJpn̄π⁻ and χcJpn̄π⁻π⁰ (J=0, 1, 2) are measured. (Throughout the text, inclusion of charge conjugate modes is implied if not stated otherwise.) The results for χc⁰pn̄π⁻ and χpn̄π⁻ are consistent with, but much more precise than, those of previous measurements. The decays of χc1pn̄π⁻ and χcJpn̄π⁻π⁰ are observed for the first time.

  11. pN0(i+) Breast Cancer: Treatment Patterns, Locoregional Recurrence, and Survival Outcomes

    SciTech Connect

    Karam, Irene; Lesperance, Maria F.; Berrang, Tanya; Speers, Caroline; Tyldesley, Scott; Truong, Pauline T.

    2013-11-15

    Purpose: To examine treatment patterns, recurrence, and survival outcomes in patients with pN0(i+) breast cancer. Methods and Materials: Subjects were 5999 women with AJCC (6th edition) pT1-3, pN0-N1a, M0 breast cancer diagnosed between 2003 and 2006. Of these, 4342 (72%) had pN0, 96 (2%) had pN0(i+), 349 (6%) had pNmic (micrometastases >0.2 mm to ≤2 mm), and 1212 (20%) had pN1a (1-3 positive macroscopic nodes) disease. Treatment characteristics and 5-year Kaplan-Meier local recurrence, regional recurrence (RR), locoregional recurrence (LRR), and overall survival were compared between nodal subgroups. Multivariable analysis was performed using Cox regression modeling. A 1:3 case-match analysis examined outcomes in pN0(i+) cases compared with pN0 controls matched for similar tumor and treatment characteristics. Results: Median follow-up was 4.8 years. Adjuvant systemic therapy use increased with nodal stage: 81%, 92%, 95%, and 94% in pN0, pN0(i+), pNmic, and pN1a disease, respectively (P<.001). Nodal radiation therapy (RT) use also increased with nodal stage: 1.7% in pN0, 27% in pN0(i+), 33% in pNmic, and 63% in pN1a cohorts (P<.001). Five-year Kaplan-Meier outcomes in pN0 versus pN0(i+) cases were as follows: local recurrence 1.7% versus 3.7% (P=.20), RR 0.5% versus 2.2% (P=.02), and LRR 2.1% versus 5.8% (P=.02). There were no RR events in 26 patients with pN0(i+) disease who received nodal RT and 2 RR events in 70 patients who did not receive nodal RT. On multivariable analysis, pN0(i+) was not associated with worse locoregional control or survival. On case-match analysis, LRR and overall survival were similar between pN0(i+) and matched pN0 counterparts. Conclusions: Nodal involvement with isolated tumor cells is not a significant prognostic factor for LRR or survival in this study's multivariable and case-match analyses. These data do not support the routine use of nodal RT in the setting of pN0(i+) disease. Prospective studies are needed to define optimal

  12. Atomic-scaled characterization of graphene PN junctions

    NASA Astrophysics Data System (ADS)

    Zhou, Xiaodong; Wang, Dennis; Dadgar, Ali; Agnihotri, Pratik; Lee, Ji Ung; Reuter, Mark C.; Ross, Frances M.; Pasupathy, Abhay N.

    Graphene p-n junctions are essential devices for studying relativistic Klein tunneling and the Veselago lensing effect in graphene. We have successfully fabricated graphene p-n junctions using both lithographically pre-patterned substrates and the stacking of vertical heterostructures. We then use our 4-probe STM system to characterize the junctions. The ability to carry out scanning electron microscopy (SEM) in our STM instrument is essential for us to locate and measure the junction interface. We obtain both the topography and dI/dV spectra at the junction area, from which we track the shift of the graphene chemical potential with position across the junction interface. This allows us to directly measure the spatial width and roughness of the junction and its potential barrier height. We will compare the junction properties of devices fabricated by the aforementioned two methods and discuss their effects on the performance as a Veselago lens.

  13. Discovery of a photoresponse amplification mechanism in compensated PN junctions

    SciTech Connect

    Zhou, Yuchun; Rahman, Samia N.; Hall, David; Lo, Yu-Hwa; Liu, Yu-Hsin; Sham, L. J.

    2015-01-19

    We report the experimental evidence of uncovering a photoresponse amplification mechanism in heavily doped, partially compensated silicon p-n junctions under very low bias voltage. We show that the observed photocurrent gain occurs at a bias that is more than an order of magnitude below the threshold voltage for conventional impact ionization. Moreover, contrary to the case of avalanche detectors and p-i-n diodes, the amplified photoresponse is enhanced rather than suppressed with increasing temperature. These distinctive characteristics lead us to hypothesize that the inelastic scattering between energetic electrons (holes) and the ionized impurities in the depletion and charge neutral regions of the p-n junction in a cyclic manner plays a significant role in the amplification process. Such an internal signal amplification mechanism, which occurs at much lower bias than impact ionization and favors room temperature over cryogenic temperature, makes it promising for practical device applications.

  14. Electrospun Composite Nanofibers of Semiconductive Polymers for Coaxial PN Junctions

    NASA Astrophysics Data System (ADS)

    Serrano, William; Thomas, Sylvia

    The objective of this research is to investigate the conditions under P3HT and Activink, semiconducting polymers, form 1 dimension (1D) coaxial p-n junctions and to characterize their behavior in the presence of UV radiation and organic gases. For the first time, fabrication and characterization of semiconductor polymeric single fiber coaxial arrangements will be studied. Electrospinning, a low cost, fast and reliable method, with a coaxial syringe arrangement will be used to fabricate these fibers. With the formation of fiber coaxial arrangements, there will be investigations of dimensionality crossovers e.g., from one-dimensional (1D) to two-dimensional (2D). Coaxial core/shell fibers have been realized as seen in a recent publication on an electrospun nanofiber p-n heterojunction of oxides (BiFeO3 and TiO2, respectively) using the electrospinning technique with hydrothermal method. In regards to organic semiconducting coaxial p-n junction nanofibers, no reported studies have been conducted, making this study fundamental and essential for organic semiconducting nano devices for flexible electronics and multi-dimensional integrated circuits.

  15. Device properties of nanopore PN junction Si for photovoltaic application

    NASA Astrophysics Data System (ADS)

    Jin, Hyunjong; Chang, Te Wei; Liu, Logan Gang

    2011-09-01

    Improvement of energy conversion efficiency of solar cells has led to innovative approaches, in particular the introduction of nanopillar photovoltaics [1]. Previous work on nanopillar Si photovoltaic has shown broadband reduction in optical reflection and enhancement of absorption [2]. Radial or axial PN junctions [3, 4] have been of high interest for improved photovoltaic devices. However, with the PN junction incorporated as part of the pillar, the discreteness of individual pillar requires additional conductive layer that would electrically short the top of each pillar for efficient carrier extraction. The fragile structure of the surface pillars would also require a protection layer for possible mechanical scratch to prevent pillars from breaking. Any additional layer that is applied, either for electrical contact or for mechanical properties may introduce additional recombination sites and also reduce the actual light absorption by the photovoltaic material. In this paper, nanopore Si photovoltaics that not only provides the advantages but also addresses the challenges of nanopillers is demonstrated. PN junction substrate of 250 nm thick N-type polycrystalline Si on P-type Si wafer is prepared. The nanopore structure is formed by using anodized aluminum oxide (AAO) as an etching mask against deep reactive ionic etching (DRIE). The device consists of semi-ordered pores of ~70 nm diameter.

  16. Non PN junction solar cells using carrier selective contacts

    NASA Astrophysics Data System (ADS)

    Bowden, Stuart; Ghosh, Kunal; Honsberg, Christiana

    2013-03-01

    A novel device concept utilizing the approach of selectively extracting carriers at the respective contacts is outlined in the work. The dominant silicon solar cell technology is based on a diffused, top-contacted p-n junction on a relatively thick silicon wafer for both commercial and laboratory solar cells. The VOC and hence the efficiency of a diffused p-n junction solar cell is limited by the emitter recombination current and a value of 720 mV is considered to be the upper limit. The value is more than 100 mV smaller than the thermodynamic limit of VOC as applicable for silicon based solar cells. Also, in diffused junction the use of thin wafers (< 50 um) are problematic because of the requirement of high temperature processing steps. But a number of roadmaps have identified solar cells manufactured on thinner silicon wafers to achieve lower cost and higher efficiency. The carrier selective contact device provides a novel alternative to diffused p-n junction solar cells by eliminating the need for complementary doping to form the emitter and hence it allows the solar cells to achieve a VOC of greater than 720 mV. Also, the complete device structure can be fabricated with low temperature thin film deposition or organic coating on silicon substrates and thus epitaxially grown silicon or kerfless silicon, in addition to standard silicon wafers can be utilized.

  17. Pn tomographic velocity and anisotropy beneath the Tibetan Plateau and the adjacent regions

    NASA Astrophysics Data System (ADS)

    Lü, Y.; Ni, S.; Liu, B.; Sun, Y.

    2011-11-01

    We present a tomographic velocity and anisotropy model of the uppermost mantle beneath the Tibetan Plateau and the adjacent regions. The investigation analyzed 105,385 Pn phase readings from the International Seismological Centre (ISC) and the China Earthquake Data Center. The average Pn velocity under the study area is approximately 8.15 km/s, with velocity perturbations up to 3-4%. We find high Pn velocities under the Indian Plate and in the Tarim and Sichuan basins, low Pn velocities under the Hindu Kush and in Myanmar and the adjacent region, and especially low Pn velocities under the area north of the Indus-Yarlung Zangbo suture. The high Pn velocity anomalies of the Indian Plate are discontinuous at the collision region in the east-west direction, indicating that the Indian Plate probably subducts in a piecewise manner. Distributions of Pn velocities are used to validate mechanisms for the subduction of the Indian Plate presented in previous studies. In addition, Pn anisotropy is obtained simultaneously with Pn velocity. At plate collision zones, the fast Pn anisotropy direction is parallel to the direction of the collision edge. We validate the existence of Pn anisotropy under these regions and discuss the relationship of anisotropy with tectonic structure and plate movement.

  18. Prognostic Value of Preoperative Serum Levels of Periostin (PN) in Early Breast Cancer (BCa).

    PubMed

    Nuzzo, Pier Vitale; Rubagotti, Alessandra; Argellati, Francesca; Di Meglio, Antonio; Zanardi, Elisa; Zinoli, Linda; Comite, Paola; Mussap, Michele; Boccardo, Francesco

    2015-01-01

    PN is a secreted cell adhesion protein critical for carcinogenesis. Elevated serum levels of PN have been implicated as playing an important role in different types of cancer, and a few reports suggest a potential role as a prognostic marker. We evaluated the prognostic significance of preoperative serum PN concentration in patients with BCa receiving curative surgery. Enzyme-Linked Immunosorbent Assay (ELISA) was performed to determine the preoperative serum PN level in 182 patients. The correlations between serum PN concentration with clinical pathological features and PN expression in primary tumor samples were analyzed. The prognostic impact of serum PN levels with all-cause and BCa-specific mortality was also investigated. Appropriate statistics were used. Elevated serum PN levels were significantly associated with patient age (p = 0.005), adjuvant systemic therapy (p = 0.04) and progesterone receptor (PgR) status (p = 0.02). No correlation between PN preoperative serum levels and other clinical-pathological parameters, including either the epithelial or the stromal PN expression of primary tumor or the combination of the two, was found. Similarly, no association between serum PN levels and either all-cause or BCa-specific mortality was found. However, subgroup analysis revealed a correlation between higher PN serum levels and all-cause mortality in patients with node-negative disease (p = 0.05) and in those with a low PgR expression (p = 0.03). Higher levels of serum PN were also found to correlate with BCa-specific mortality in the subgroup of patients who did not receive any adjuvant systemic therapy (p = 0.04). Our findings suggest that PN was detectable in the serum of early BCa patients before surgery and increased base-line serum levels predicted worse long-term survival outcomes in specific subgroups of patients. PMID:26225965

  19. ZnO PN Junctions for Highly-Efficient, Low-Cost Light Emitting Diodes

    SciTech Connect

    David P. Norton; Stephen Pearton; Fan Ren

    2007-09-30

    By 2015, the US Department of Energy has set as a goal the development of advanced solid state lighting technologies that are more energy efficient, longer lasting, and more cost-effective than current technology. One approach that is most attractive is to utilize light-emitting diode technologies. Although III-V compound semiconductors have been the primary focus in pursuing this objective, ZnO-based materials present some distinct advantages that could yield success in meeting this objective. As with the nitrides, ZnO is a direct bandgap semiconductor whose gap energy (3.2 eV) can be tuned from 3.0 to 4 eV with substitution of Mg for higher bandgap, Cd for lower bandgap. ZnO has an exciton binding energy of 60 meV, which is larger than that for the nitrides, indicating that it should be a superior light emitting semiconductor. Furthermore, ZnO thin films can be deposited at temperatures on the order of 400-600 C, which is significantly lower than that for the nitrides and should lead to lower manufacturing costs. It has also been demonstrated that functional ZnO electronic devices can be fabricated on inexpensive substrates, such as glass. Therefore, for the large-area photonic application of solid state lighting, ZnO holds unique potential. A significant impediment to exploiting ZnO in light-emitting applications has been the absence of effective p-type carrier doping. However, the recent realization of acceptor-doped ZnO material overcomes this impediment, opening the door to ZnO light emitting diode development In this project, the synthesis and properties of ZnO-based pn junctions for light emitting diodes was investigated. The focus was on three issues most pertinent to realizing a ZnO-based solid state lighting technology, namely (1) achieving high p-type carrier concentrations in epitaxial and polycrystalline films, (2) realizing band edge emission from pn homojunctions, and (3) investigating pn heterojunction constructs that should yield efficient light

  20. Experimental study of exclusive $^2$H$(e,e^\\prime p)n$ reaction mechanisms at high $Q^2$

    SciTech Connect

    Kim Egiyan; Gegham Asryan; Nerses Gevorgyan; Keith Griffioen; Jean Laget; Sebastian Kuhn; Gary Adams; Moscov Amaryan; Pawel Ambrozewicz; Marco Anghinolfi; Gerard Audit; Harutyun AVAKIAN; Harutyun Avakian; Hovhannes Baghdasaryan; Nathan Baillie; Jacques Ball; Nathan Baltzell; Steve Barrow; Vitaly Baturin; Marco Battaglieri; Ivan Bedlinski; Ivan Bedlinskiy; Mehmet Bektasoglu; Matthew Bellis; Nawal Benmouna; Barry Berman; Angela Biselli; Lukasz Blaszczyk; Sylvain Bouchigny; Sergey Boyarinov; Robert Bradford; Derek Branford; William Briscoe; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; Sharon Careccia; Daniel Carman; Antoine Cazes; Shifeng Chen; Philip Cole; Patrick Collins; Philip Coltharp; Dieter Cords; Pietro Corvisiero; Donald Crabb; Volker Crede; John Cummings; Natalya Dashyan; Rita De Masi; Raffaella De Vita; Enzo De Sanctis; Pavel Degtiarenko; Haluk Denizli; Lawrence Dennis; Alexandre Deur; Kahanawita Dharmawardane; Richard Dickson; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; Michael Dugger; Steven Dytman; Oleksandr Dzyubak; Hovanes Egiyan; Lamiaa Elfassi; Latifa Elouadrhiri; Paul Eugenio; Renee Fatemi; Gleb Fedotov; Gerald Feldman; Robert Feuerbach; Robert Fersch; Michel Garcon; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; John Goetz; Atilla Gonenc; Christopher Gordon; Ralf Gothe; Michel Guidal; Matthieu Guillo; Hayko Guler; Lei Guo; Vardan Gyurjyan; Cynthia Hadjidakis; Kawtar Hafidi; Hayk Hakobyan; Rafael Hakobyan; Charles Hanretty; John Hardie; F. Hersman; Kenneth Hicks; Ishaq Hleiqawi; Maurik Holtrop; Charles Hyde-Wright; Yordanka Ilieva; David Ireland; Boris Ishkhanov; Eugeny Isupov; Mark Ito; David Jenkins; Hyon-Suk Jo; Kyungseon Joo; Henry Juengst; Narbe Kalantarians; James Kellie; Mahbubul Khandaker; Wooyoung Kim; Andreas Klein; Franz Klein; Alexei Klimenko; Mikhail Kossov; Zebulun Krahn; Laird Kramer; V. Kubarovsky; Joachim Kuhn; Sergey Kuleshov; Jeff Lachniet; Jorn Langheinrich; David Lawrence; Ji Li; Kenneth Livingston; Haiyun Lu; Marion MacCormick; Claude Marchand; Nikolai Markov; Paul Mattione; Simeon McAleer; Bryan McKinnon; John McNabb; Bernhard Mecking; Surik Mehrabyan; Joseph Melone; Mac Mestayer; Curtis Meyer; Tsutomu Mibe; Konstantin Mikhaylov; Ralph Minehart; Marco Mirazita; Rory Miskimen; Viktor Mokeev; Kei Moriya; Steven Morrow; Maryam Moteabbed; James Mueller; Edwin Munevar Espitia; Gordon Mutchler; Pawel Nadel-Turonski; Rakhsha Nasseripour; Silvia Niccolai; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Grant O'Rielly; Mikhail Osipenko; Alexander Ostrovidov; Kijun Park; Evgueni Pasyuk; Craig Paterson; Sergio Pereira; Joshua Pierce; Nikolay Pivnyuk; Dinko Pocanic; Oleg Pogorelko; Sergey Pozdnyakov; Barry Preedom; John Price; Yelena Prok; Dan Protopopescu; Brian Raue; Gregory Riccardi; Giovanni Ricco; Marco Ripani; Barry Ritchie; Federico Ronchetti; Guenther Rosner; Patrizia Rossi; Franck Sabatie; Julian Salamanca; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Youri Sharabian; Nikolay Shvedunov; Alexander Skabelin; Elton Smith; Lee Smith; Daniel Sober; Daria Sokhan; Aleksey Stavinskiy; Samuel Stepanyan; Stepan Stepanyan; Burnham Stokes; Paul Stoler; Steffen Strauch; Mauro Taiuti; David Tedeschi; Ulrike Thoma; Avtandil Tkabladze; Svyatoslav Tkachenko; Luminita Todor; Clarisse Tur; Maurizio Ungaro; Michael Vineyard; Alexander Vlassov; Daniel Watts; Lawrence Weinstein; Dennis Weygand; M. Williams; Elliott Wolin; Michael Wood; Amrit Yegneswaran; Lorenzo Zana; Jixie Zhang; Bo Zhao; Zhiwen Zhao

    2007-06-01

    The reaction {sup 2}H(e,e{prime} p)n has been studied with full kinematic coverage for photon virtuality 1.75 < 5.5 {approx} GeV{sup 2}. Comparisons of experimental data with theory indicate that for very low values of neutron recoil momentum (p{sub n} < 100 MeV/c) the neutron is primarily a spectator and the reaction can be described by the plane-wave impulse approximation. For 100 < 750 MeV/c proton-neutron rescattering dominates the cross section, while {Delta} production followed by the N{Delta} {yields} NN transition is the primary contribution at higher momenta.

  1. Eccentric orbit E/IMRI gravitational wave fluxes to 7PN order

    NASA Astrophysics Data System (ADS)

    Forseth, Erik; Evans, Charles R.; Hopper, Seth

    2016-03-01

    Knowledge of gravitational wave fluxes (energy and angular momentum, at both infinity and the horizon) from eccentric-orbit inspirals is extended from 3PN to 7PN order at lowest order in small mass ratio. Previous post-Newtonian eccentric-orbit results up to 3PN relative order are confirmed by our new black hole perturbation calculations. The calculations are based on Mano, Suzuki, and Takasugi (MST) analytic function expansions, and results are computed to 200 decimal places of accuracy using Mathematica. Over 1,700 distinct orbits were computed, each with as many as 7,000 Fourier-harmonic modes. A large number of PN coefficients between 3.5PN and 7PN orders were determined, either in exact analytic form or with accurate numerical values, in expansions in powers of a PN compactness parameter and its logarithm, and powers of eccentricity. We show a parametrization that removes singularities in the fluxes as the eccentricity approaches unity, thus making the expansions more convergent at high eccentricity. We also found (nearly) arbitrarily accurate expansions for the previously discussed 1.5PN, 2.5PN, and 3PN hereditary terms.

  2. Trees increase their P:N ratio with size

    PubMed Central

    Sardans, J; Peñuelas, J.

    2015-01-01

    Aim Phosphorus (P) tends to become limiting in aging terrestrial ecosystems, and its resorption efficiency is higher than for other elements such as nitrogen (N). We thus hypothesized that trees should store more P than those other elements such as N when tree size increases and that this process should be enhanced in slow-growing late successional trees. Location Catalan forests. Methods We have used data from the Catalan Forest Inventory that contains field data of the P and N contents of total aboveground, foliar and woody biomasses of the diverse Mediterranean, temperate and alpine forests of Catalonia (1018 sites). We used correlation and general lineal models (GLM) to analyze the allometric relationships between nutrient contents of different aboveground biomass fractions (foliar, branches and stems) and total aboveground biomass. Results Aboveground forest P content increases proportionally more than aboveground forest N content with increasing aboveground biomass. Two mechanisms underlie this. First, woody biomass increases proportionally more than foliar biomass having woody biomass higher P:N ratio than foliar biomass. Second, wood P:N ratio increases with tree size. These results are consistent with the generally higher foliar resorption of P than of N. Slow-growing species accumulate more P in total aboveground with size than fast-growing species mainly as a result of their large capacity to store P in wood. Main conclusions Trees may have thus developed long-term adaptive mechanisms to store P in biomass, mainly in wood, thereby slowing the loss of P from the ecosystems, reducing its availability for competitors, and implying an increase in the P:N ratio in forest biomass with aging. This trend to accumulate more P than N with size is more accentuated in slow-growing, large, long-living species of late successional stages. This way they partly counterbalance the gradual decrease of P in the soil. PMID:25983656

  3. Pn anisotropic tomography and dynamics under eastern Tibetan plateau

    NASA Astrophysics Data System (ADS)

    Lei, Jianshe; Li, Yuan; Xie, Furen; Teng, Jiwen; Zhang, Guangwei; Sun, Changqing; Zha, Xiaohui

    2014-03-01

    We present a new anisotropic tomographic model of the uppermost mantle around eastern Tibet using Pn traveltime data from a newly deployed temporary seismic array and recent observation bulletins of Chinese provincial networks. Our results are generally consistent with previous results but provide new insights into the dynamics of Tibetan plateau. Prominent high-velocity (high-V) anomalies are visible under Alashan block and Qaidam and Sichuan basins, which clearly outline their tectonic margins. A distinct high-V zone representing the double-sided subduction of Indo-Eurasian plates is imaged from Lhasa block to the south of Qaidam basin. A pronounced low-velocity (low-V) zone is observed from Songpan-Ganzi block to southern Chuan-Dian diamond block, suggesting the existence of hot material upwelling there. Crustal strong earthquakes frequently occurred around high-V anomalies or transition zones from high-V to low-V anomalies, suggesting that these earthquakes could be related to lateral heterogeneities in the mantle. The Pn fast direction approximately rotates around Eastern Himalayan Syntaxis, and it is tangential to the margins of Sichuan basin, suggesting that the mantle material flow of Tibetan plateau may have affected east China. In the Yunnan region to the south of 26°N, the Pn fast direction is different from SKS splitting results, indicating that the mantle lithosphere could be mechanically decoupled at certain depth below the uppermost mantle, which might be attributable to the subduction of Indian (or Burma) slab. Although the correlation between anisotropy and velocity is complicated, anisotropy strength could be associated with the pattern of velocity anomalies in the region.

  4. Pn anisotropic tomography under the entire Tienshan orogenic belt

    NASA Astrophysics Data System (ADS)

    Zhou, Zhigang; Lei, Jianshe

    2015-11-01

    We present a new anisotropic tomography of the uppermost mantle under the Tienshan orogenic belt and surrounding regions using a number of Pn arrival-time data hand-picked from portable seismic stations and chosen from the Xinjiang provincial observation bulletins and the EHB datasets. Our results exhibit prominent lateral heterogeneities in the study region. Distinct low-velocity anomalies are visible under the tectonically active regions, such as the Tienshan orogenic belt and western Kunlun Mountains, whereas pronounced high-velocity anomalies are imaged beneath the stable blocks, such as the Kazakh shield, the Junggar, Tarim, Qaidam, and Turpan-Hami basins, and the Tajik depression. Most strong earthquakes (Ms > 7.0) are mainly distributed along the transition zone of high to low velocity anomalies, suggesting a possible correlation between the strong earthquakes and the upper mantle structure. The fast directions of Pn anisotropy beneath the Tienshan orogenic belt are generally parallel to its striking orientation, whereas those beneath Pamir show a northward arc-shaped distribution. The Pn fast-velocity directions on the boundaries of the Kazakh shield and the Tarim and Junngar basins are approximately perpendicular to the strike of the Tienshan orogenic belt. By integrating with previous findings, our results suggest that the Tarim and Kazakh lithospheric materials could have underthrusted beneath the Tienshan orogenic belt that leads to the hot mantle material upwelling under the Tienshan orogenic belt, which is attributable to the Indo-Asian collision. These dynamic processes could play important roles in the Tienshan mountain building.

  5. A transparent ultraviolet triggered amorphous selenium p-n junction

    NASA Astrophysics Data System (ADS)

    Saito, Ichitaro; Miyazaki, Wataru; Onishi, Masanori; Kudo, Yuki; Masuzawa, Tomoaki; Yamada, Takatoshi; Koh, Angel; Chua, Daniel; Soga, Kenichi; Overend, Mauro; Aono, Masami; Amaratunga, Gehan A. J.; Okano, Ken

    2011-04-01

    This paper will introduce a semitransparent amorphous selenium (a-Se) film exhibiting photovoltaic effects under ultraviolet light created through a simple and inexpensive method. We found that chlorine can be doped into a-Se through electrolysis of saturated salt water, and converts the weak p-type material into an n-type material. Furthermore, we found that a p-n diode fabricated through this process has shown an open circuit voltage of 0.35 V toward ultraviolet illumination. Our results suggest the possibility of doping control depending on the electric current during electrolysis and the possibility of developing a simple doping method for amorphous photoconductors.

  6. Reflecting boundary conditions for graded p-n junctions

    NASA Technical Reports Server (NTRS)

    Schacham, S. E.

    1990-01-01

    In a graded junction, the formalism for handling reflecting boundary conditions must be modified. Since a significant drift term is present, zero recombination velocity at the surface does not imply a zero excess carrier gradient but rather zero overall flux. A model for analyzing p-n junctions fabricated by implantation or diffusion is presented, assuming the dominant recombination mechanism in the graded region is Auger. The model enables optimization of diode design. By proper selection of parameters, mainly by reducing surface concentration or by increasing the steepness of the dopant profile, it is possible to drastically reduce the saturation current generated by the graded region.

  7. Time Shifted PN Codes for CW Lidar, Radar, and Sonar

    NASA Technical Reports Server (NTRS)

    Campbell, Joel F. (Inventor); Prasad, Narasimha S. (Inventor); Harrison, Fenton W. (Inventor); Flood, Michael A. (Inventor)

    2013-01-01

    A continuous wave Light Detection and Ranging (CW LiDAR) system utilizes two or more laser frequencies and time or range shifted pseudorandom noise (PN) codes to discriminate between the laser frequencies. The performance of these codes can be improved by subtracting out the bias before processing. The CW LiDAR system may be mounted to an artificial satellite orbiting the earth, and the relative strength of the return signal for each frequency can be utilized to determine the concentration of selected gases or other substances in the atmosphere.

  8. Ferroelectric-semiconductor photovoltaics: Non-PN junction solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Fude; Wang, Wentao; Wang, Lei; Yang, Guandong

    2014-03-01

    Traditional positive-negative (PN) junction based solar cells have many limitations. Herein, we introduce ferroelectric-semiconductor solar cells that use the bound surface charges of the ferroelectric for achieving charge separation in the semiconductor. The feasibility of the new concept cells was verified both experimentally and theoretically in detail. The new cells are unique in that free charge carriers and fixed charge carriers are physically separated from each other. The feature allows us to go beyond traditional junction-based structures and have more freedom in material selection, device design, and fabrication.

  9. Photocurrent generation efficiency of a carbon nanotube pn junction

    NASA Astrophysics Data System (ADS)

    McCulley, Daniel; Aspitarte, Lee; Minot, Ethan

    Carrier multiplication effects can enhance the quantum efficiency of photovoltaic devices. For example, quantum dot solar cells have demonstrated photon-to-electron conversion efficiencies greater than 100% when photon energies exceed twice the band gap. Carbon nanotube photodiodes exhibit carrier multiplication effects (Gabor et al., Science 2009), but the quantum efficiency of such photodiodes has not previously been characterized. We have reproduced the carrier multiplication phenomena in individual CNT pn junctions and investigated the conditions under which it occurs. We will present early results quantifying the internal quantum efficiency of the process.

  10. A transparent ultraviolet triggered amorphous selenium p-n junction

    SciTech Connect

    Saito, Ichitaro; Soga, Kenichi; Overend, Mauro; Amaratunga, Gehan A. J.; Miyazaki, Wataru; Onishi, Masanori; Masuzawa, Tomoaki; Okano, Ken; Kudo, Yuki; Yamada, Takatoshi; Koh, Angel; Chua, Daniel; Aono, Masami

    2011-04-11

    This paper will introduce a semitransparent amorphous selenium (a-Se) film exhibiting photovoltaic effects under ultraviolet light created through a simple and inexpensive method. We found that chlorine can be doped into a-Se through electrolysis of saturated salt water, and converts the weak p-type material into an n-type material. Furthermore, we found that a p-n diode fabricated through this process has shown an open circuit voltage of 0.35 V toward ultraviolet illumination. Our results suggest the possibility of doping control depending on the electric current during electrolysis and the possibility of developing a simple doping method for amorphous photoconductors.

  11. Application of CBZ dimer, C343 and SQ dye as photosensitizers for pn-tandem DSCs

    NASA Astrophysics Data System (ADS)

    Lee, Yong Hyi; Park, Ji Young; Thogiti, Suresh; Cheruku, Rajesh; Kim, Jae Hong

    2016-07-01

    A pn-tandem dye-sensitized solar cell ( pn-DSC) was prepared with three different sensitized dyes CBZ Dimer (CBZD), C343, and SQ in two different compartments of the n-type or p-type cells. The constructed tandem solar cell was exhibited considerable improvement in experimental pn-DSCs parameters, open-circuit voltage, short-circuit current, fill factor, etc. These results were achieved under air mass 1.5 illumination with three different sensitized dyes in the upper and lower compartment of the pn-DSCs. These results demonstrate a complementary absorption among the two photoelectrodes in the pn-DSCs is a good approach to the efficient and low cost pn-DSCs. [Figure not available: see fulltext.

  12. n-p Short-Range Correlations from (p,2p+n) Measurements

    NASA Astrophysics Data System (ADS)

    Tang, A.; Watson, J. W.; Aclander, J.; Alster, J.; Asryan, G.; Averichev, Y.; Barton, D.; Baturin, V.; Bukhtoyarova, N.; Carroll, A.; Gushue, S.; Heppelmann, S.; Leksanov, A.; Makdisi, Y.; Malki, A.; Minina, E.; Navon, I.; Nicholson, H.; Ogawa, A.; Panebratsev, Yu.; Piasetzky, E.; Schetkovsky, A.; Shimanskiy, S.; Zhalov, D.

    2003-01-01

    We studied the 12C(p,2p+n) reaction at beam momenta of 5.9, 8.0, and 9.0 GeV/c. For quasielastic (p,2p) events pf, the momentum of the knocked-out proton before the reaction, was compared (event by event) with pn, the coincident neutron momentum. For |pn|>kF=0.220 GeV/c (the Fermi momentum) a strong back-to-back directional correlation between pf and pn was observed, indicative of short-range n-p correlations. From pn and pf we constructed the distributions of c.m. and relative motion in the longitudinal direction for correlated pairs. We also determined that 49±13% of events with |pf|>kF had directionally correlated neutrons with |pn|>kF.

  13. High voltage thermally diffused p(+)n solar cells

    NASA Technical Reports Server (NTRS)

    Faur, M.; Faur, M.; Flood, D. J.; Brinker, D. J.; Weinberg, I.; Goradia, C.; Fatemi, N.; Goradia, M.; Thesling, W.

    1991-01-01

    The possibility of fabricating thermally diffused p(+)n InP solar-cells with high open-circuit voltage without sacrificing the short circuit current is discussed. The p(+)n InP junctions were formed by Cd and Zn diffusion through a 3-5-nm-thick anodic or chemical phosphorus-rich oxide cap layer grown on n:InP:S (with ND-NA = 3.5 x 10 exp 16 and 4.5 x 10 exp 17/cu cm) Czochralski LEC-grown substrates. After thinning the emitter from its initial thickness of 1 to 2.5 micron down to 0.06-0.15 micron, the maximum efficiency was found when the emitter was 0.2 to 0.3 micron thick. Typical AM0, 25 C values of 854-860 mV were achieved for Voc, Jsc values were from 25.9 to 29.1 mA/sq cm using only the P-rich passivating layer left after the thinning process as an antireflection coating.

  14. Single pilus motor forces exceed 100 pN.

    PubMed

    Maier, Berenike; Potter, Laura; So, Magdalene; Long, Cynthia D; Seifert, Hank S; Sheetz, Michael P

    2002-12-10

    Force production by type IV pilus retraction is critical for infectivity of Neisseria gonorrhoeae and DNA transfer. We investigated the roles of pilus number and the retraction motor, PilT, in force generation in vivo at the single-molecule level and found that individual retraction events are generated by a single pilus fiber, and only one PilT complex powers retraction. Retraction velocity is constant at low forces but decreases at forces greater than 40 pN, giving a remarkably high average stall force of 110 +/- 30 pN. Further insights into the molecular mechanism of force generation are gained from the effect of ATP-depletion, which reduces the rate of retraction but not the stall force. Energetic considerations suggest that more than one ATP is involved in the removal of a single pilin subunit from a pilus. The results are most consistent with a model in which the ATPase PilT forms an oligomer that disassembles the pilus by a cooperative conformational change. PMID:12446837

  15. The performance of a sequential acquisition system for PN codes

    NASA Astrophysics Data System (ADS)

    Kerr, R. W.; Arakaki, E. M.; Huang, M. Y.

    Direct sequence spread spectrum techniques are being applied in an increasing number of advanced communication systems where anti-jam (AJ), low probability of intercept (LPI), or code division multiple access (CDMA) capabilities are required. In all these systems, rapid acquisition of long PN code is a system necessity. Generally, acquisition of long PN codes is accomplished by correlation measurements of the incoming sequence with a locally generated code sequence. However, instead of utilizing fixed integration times, a sequential acquisition technique could also be used for active correlation, which results in greatly reduced acquisition times. TRW has designed and completed a limited production of 33 spread spectrum receivers for use with the NASA Tracking Data Relay Satellite System (TDRSS). The receivers provide multiple access and ranging capability while simultaneously decreasing the transmitted power flux density to meet CCIR restrictions. This paper presents the analysis, hardware description, and performance of the sequential code acquisition system implemented on these receivers. A unique noise calibration process, which holds the key to successful operation of these receivers, is described in detail.

  16. High-frequency Pn,Sn phases recorded by ocean bottom seismometers on the Cocos plate

    SciTech Connect

    McCreery, C.S.

    1981-05-01

    Data from ocean bottom seismometers located on the Cocos plate indicate that high-frequency Pn,Sn phases are generated by earthquakes along the subducting margin of that plate and are propagated across the plate. The Sn phase appears to be severely attenuated as it approaches the ridge crest. Estimates of Pn velocity are lower than previous extimates for western Pacific paths, which may indicate a relationship between Pn,Sn velocity and lithospheric age. High frequencies found in these phases suggest that Q for Pn,Sn propagation across the Cocos plate is similar to that for the western Pacific.

  17. Eccentric-orbit extreme-mass-ratio inspiral gravitational wave energy fluxes to 7PN order

    NASA Astrophysics Data System (ADS)

    Forseth, Erik; Evans, Charles R.; Hopper, Seth

    2016-03-01

    We present new results through 7PN order on the energy flux from eccentric extreme-mass-ratio binaries. The black hole perturbation calculations are made at very high accuracy (200 decimal places) using a Mathematica code based on the Mano-Suzuki-Takasugi analytic function expansion formalism. All published coefficients in the expansion through 3PN order at lowest order in the mass ratio are confirmed and new analytic and numeric terms are found to high order in powers of e2 at post-Newtonian orders between 3.5PN and 7PN. We also show original work in finding (nearly) arbitrarily accurate expansions for hereditary terms at 1.5PN, 2.5PN, and 3PN orders. An asymptotic analysis is developed that guides an understanding of eccentricity singular factors, which diverge at unit eccentricity and which appear at each PN order. We fit to a model at each PN order that includes these eccentricity singular factors, which allows the flux to be accurately determined out to e →1 .

  18. Zinc oxide and metal phthalocyanine based hybrid P-N junction diodes

    NASA Astrophysics Data System (ADS)

    Singh, Budhi; Ghosh, Subhasis

    2013-09-01

    Hybrid p-n junction diode based on zinc oxide (ZnO) and metal phthalocyanine (MePc) has been demonstrated using highly conducting Al doped ZnO as transparent electrode. Three different MePcs: copper phthalocyanine, zinc phthalocyanine (ZnPc), and cobalt phthalocyanine are used as p-type layer in hybrid p-n junction. It is found that most desirable performance can be achieved in ZnO/ZnPc based hybrid p-n junction. The depletion region in hybrid p-n junctions has been measured using current-voltage and capacitance-voltage characteristics.

  19. Isoelectronic analogues of PN: Remarkably stable multiply charged cations

    SciTech Connect

    Wong, Ming Wah; Radom, L. )

    1990-01-25

    The structures and stabilities of PN and its 27 isoelectronic analogues, CS, SiO, BCl, AlF, BeAr, MgNe, Sn{sup +}, PO{sup +}, CCl{sup +}, SiF{sup +}, BAr{sup +}, AlNe{sup +}, SO{sup 2+}, NCl{sup 2+}, PF{sup 2+}, CAr{sup 2+}, SiNe{sup 2+}, OCl{sup 3+}, SF{sup 3+}, NAr{sup 3+}, PNe{sup 3+}, FCl{sup 4+}, OAr{sup 4+}, SNe{sup 4+}, FAr{sup 5+}, ClNe{sup 5+}, and ArNe{sup 6+}, have been examined by ab initio molecular orbital theory. The CASSCF/6-311G(MC)(d) level was used to determine the ground-state potential energy curves and spectroscopic constants for the 28 diatomic systems. Equilibrium structures were also obtained with the 6-311G(MC)(d) basis set at the MP3 and ST4CCD levels, and dissociation energies were determined at the MP4/6-311 + G(MC)(2df) and MP4/6-311 + G(MC)(3d2f) levels. For the neutral and monocation analogues of PN, the calculated equilibrium geometries (at MP3/6-311G(MC)(d)) and dissociation energies (at MP4/6-311 + G(MC)(3d2f)) are in very good agreement with available experimental values. All the dication analogues of PN, namely, SO{sup 2+}, NCl{sup 2+}, PF{sup 2+}, CAr{sup 2+}, and SiNe{sup 2+}, are predicted to be experimentally observable species. Of these, the SO{sup 2+}, NCl{sup 2+}, and CAr{sup 2+} dications are calculated to be kinetically stable species, with large barriers associated with the exothermic charge-separation reactions, while the PF{sup 2+} and SiNe{sup 2+} dications are predicted not only to be kinetically stable but also to be thermodynamically stable species.

  20. PN populations in the Local Group and distant stellar populations

    NASA Astrophysics Data System (ADS)

    Reid, Warren Alfred

    2015-08-01

    Our understanding of galactic structure and evolution is far from complete. Within the past twelve months we have learnt that the Milky Way is about 50% wider than was previously thought. As a consequence, new models are being developed that force us to reassess the kinematic structure of our Galaxy. Similarly, we need to take a fresh look at the halo structure of external galaxies in our Local Group. Studies of stellar populations, star-forming regions, clusters, the interstellar medium, elemental abundances and late stellar evolution are all required in order to understand how galactic assembly has occurred as we see it.PNe play an important role in this investigation by providing a measure of stellar age, mass, abundances, morphology, kinematics and synthesized matter that is returned to the interstellar medium (ISM). PN populations in the halos can be compared to those deeper within each galaxy to reveal any differences in chemical composition that may, through a method of chemical tagging show signs of stellar migration and galactic entwining.In this talk I will outline the advances that have been made in uncovering the full number of PNe in our Local Group galaxies. Current numbers will be presented and compared to total population estimates based on galactic mass and luminosity. A near complete census of PNe is crucial to understanding the initial-to-final mass relation for stars with mass >1 to <8 times the mass of the sun. It also allows us to extract more evolutionary information from luminosity functions and compare dust-to-gas ratios from PNe in different galactic locations. Nucleosynthesised material returned to the ISM during the PN phase can be compared to non-synthesised matter to expose the role PNe play in enriching the galactic environment.With new data provided by the Gaia satellite, space-based telescopes and the rise of giant and extra-large telescopes supplementing future space telescope missions, we are on the verge of observing and

  1. Discussion on origin of Pn velocity variation in China and adjacent region

    NASA Astrophysics Data System (ADS)

    Pei, Shun-Ping; Xu, Zhong-Huai; Wang, Su-Yun

    2004-01-01

    Pn velocity lateral variation and anisotropy images were reconstructed by adding about 50 000 travel times from the regional seismic networks to the datum set of near 40 000 travel times from National Seismic Network of China used by WANG, et al. We discussed the relation of Pn velocity variation to Moho depth, Earth’s heat flow, distribution of Cenozoic volcanic rock and the result of rock experiment under high pressure and high temperature. The result of quantitative analysis indicates that Pn velocity is positively correlated with the crust thickness and negatively correlated with the Earth’s heat flow. Two linear regression equations, one between Pn velocity and crust thickness, and the other between Pn velocity and heat flow, were obtained. The rate of variation of Pn velocity ν p with pressure P, ∂ ν p/∂ P, estimated from the velocity variation with crust thickness, ∂ ν p/∂ H is close to the result obtained from the rock experiment under high pressure and high temperature. If the effect of crust thickness on Pn velocity is deducted from the velocity variation, then the low Pn velocity beneath Qinghai-Xizang plateau is more notable. The low Pn velocity regions well agree with the Cenozoic volcanic rock. In the several regions with significant anisotropy, the direction of fast Pn velocity is consistent with the orientation of maximum principal crustal compressive stress, and also with the direction of present-day crustal movement. It indicates that the fast Pn velocity direction may be related to the deformation or flow of top mantle material along the direction of maximum pressure.

  2. Stochastic jumps of magnetization in [Mn{(R/S)-pn}]2[Mn{(R/S)-pn}2(H2O)][Cr(CN)6]2 molecular magnet

    NASA Astrophysics Data System (ADS)

    Kirman, M. V.; Talantsev, A. D.; Koplak, O. V.; Morgunov, R. B.

    2015-03-01

    Series of stochastic jumps of the magnetic moment (up to five individual jumps) have been observed at the demagnetization of single crystals of [Mn{(R/S)-pn}]2[Mn{(R/S)-pn}2(H2O)][Cr(CN)6]2 molecular magnet in a narrow range of magnetic fields near the coercive force ( H c = 7.5 Oe). The magnetic field at which jumps of the magnetization arise decreases with an increase in the temperature.

  3. Surface and implantation effects on p-n junctions

    NASA Technical Reports Server (NTRS)

    Schacham, Samuel E.; Finkman, Eliezer

    1990-01-01

    The contribution of the graded region of implanted p-n junctions is analyzed using an exponential profile. Though previously neglected, it was recently shown that this contribution to the saturation current of HgCdTe diodes is significant. Assuming a dominant Auger recombination, an analytical solution to the continuity equation is obtained. An expression for the current generation by the graded region is presented for both ohmic and reflecting boundary conditions. A revised condition for a wide region is derived. When the region is narrow, the current differs drastically from that of the zero-gradient case. The effects of the junction depth and the substrate and surface concentrations on the current are investigated. It is shown that the reverse current does not saturate.

  4. Shallow mantle velocities beneath the southern Appalachians from Pn phases

    NASA Astrophysics Data System (ADS)

    MacDougall, Julia G.; Fischer, Karen M.; Forsyth, Donald W.; Hawman, Robert B.; Wagner, Lara S.

    2015-01-01

    constrain mantle structure that might contribute to the topography of the southern Appalachian Mountains, Pn phases from regional earthquakes recorded in northern Georgia by EarthScope Southeastern Suture of the Appalachian Margin Experiment and Transportable Array stations were used to solve for shallow mantle P wave velocities. Mantle velocities vary laterally, with values of 7.6-7.8 km/s beneath the higher elevations of the Blue Ridge terrane and northwestern flank of the Inner Piedmont terranes and values of 8.3-8.5 km/s farther south where elevation is lower. The zone of low-velocity mantle could represent a source of buoyancy that helps to support the higher elevations, in addition to the root of thickened crust that also exists beneath the mountains.

  5. Rectifying behaviour of spin coated pn hetero-junction

    SciTech Connect

    Yogamalar, N. Rajeswari; Bose, A. Chandra

    2015-06-24

    Rectifying pn hetero- junction is fabricated with an acceptor p-type organic semiconductor namely tetra- chloro dihydroxy tetra-iodo fluorescein (Rose Bengal (RB)) followed by an inorganic n-type ZnO semiconductor on indium tin oxide (ITO) substrate. The n-type ZnO films are formed by unintentional doping and doping with aluminium (Al) and yttrium (Y) donors. The surface morphology and the distribution of grains are observed from scanning electron microscopy (SEM) and atomic force microscopy (AFM). The current-voltage (I-V) characteristic of the rectifying diode is measured to characterize the junction properties. The I-V plots obtained from the hetero- junction with electric contact shows a diode characteristic different from that of an ideal behavior. The overall efficiency of the diode exhibits a greater dependency on the film crystallinity, carrier concentration, and reverse saturation current.

  6. Polarimetry of R Aqr and PN M2-9

    NASA Astrophysics Data System (ADS)

    Navarro, Silvana G.; Sabin, Laurence; Ramírez Vélez; , Julio; Hiriart, David

    2014-08-01

    The bipolar or more complex morphology observed in planetary nebulae have been explained by two principal hypothesis: by the existence of a companion and an accreting disk or by the effects of magnetic field, (or a combination of both). Symbiotics are binary systems and some of them show morphologies similar to those observed on planetary nebulae. This fact could support the binary hypothesis for PNe. We have therefore performed polarimetric observations of symbiotic systems and some planetary nebulae in order, first to detect linear polarisation with POLIMA at the San Pedro Mártir observatory, and ultimately to prove the existence and physical properties of those disks. We present here the first results of a project dedicated to the analysis of the polarisation observed in evolved objects starting with the PN M2-9 and R Aqr.

  7. Rectifying behaviour of spin coated pn hetero-junction

    NASA Astrophysics Data System (ADS)

    Yogamalar, N. Rajeswari; Bose, A. Chandra

    2015-06-01

    Rectifying pn hetero- junction is fabricated with an acceptor p-type organic semiconductor namely tetra- chloro dihydroxy tetra-iodo fluorescein (Rose Bengal (RB)) followed by an inorganic n-type ZnO semiconductor on indium tin oxide (ITO) substrate. The n-type ZnO films are formed by unintentional doping and doping with aluminium (Al) and yttrium (Y) donors. The surface morphology and the distribution of grains are observed from scanning electron microscopy (SEM) and atomic force microscopy (AFM). The current-voltage (I-V) characteristic of the rectifying diode is measured to characterize the junction properties. The I-V plots obtained from the hetero- junction with electric contact shows a diode characteristic different from that of an ideal behavior. The overall efficiency of the diode exhibits a greater dependency on the film crystallinity, carrier concentration, and reverse saturation current.

  8. An Investigation of NCLEX-PN Performance and Student Perceptions among Practical Nursing Graduates

    ERIC Educational Resources Information Center

    Abston-Coleman, Sharon L.; Levy, Dessie R.

    2010-01-01

    Students in practical nursing programs require 32 weeks of coursework (1 academic year) and completion of a national licensing exam (NCLEX-PN) to secure employment. The purpose of this study was to identify selected academic variables that were related to NCLEX-PN performance for first-time test takers of two types of practical nursing programs at…

  9. Naringenin (NAR) and 8-prenylnaringenin (8-PN) reduce the developmental competence of porcine oocytes in vitro.

    PubMed

    Solak, Kamila A; Santos, Regiane R; van den Berg, Martin; Blaauboer, Bas J; Roelen, Bernard A J; van Duursen, Majorie B M

    2014-11-01

    Flavanones such as naringenin (NAR) and 8-prenylnaringenin (8-PN) are increasingly used as dietary supplements despite scientific concern regarding adverse effects on female reproduction upon excessive intake. In the present study, NAR and 8-PN (0.3-1μM) significantly affected porcine oocyte maturation in vitro by decreasing cumulus expansion. In addition, NAR and 8-PN decreased percentages of meiotic spindle formation, oocyte cleavage and blastocyst formation. The effects of NAR and 8-PN were different from estradiol (3.12μM)-induced effects. Still, the flavanone-induced effects were observed at concentrations that can be found in human plasma upon supplement intake and that resemble physiological estrogen equivalence levels in follicular fluids. Considering that abnormal oocyte maturation can cause subfertility, our study warrants that precautions are in place and excessive intake of NAR and 8-PN e.g. via dietary supplements should be avoided by women. PMID:24905140

  10. 2PN light propagation in the scalar - tensor theory: an N - point mass case

    NASA Astrophysics Data System (ADS)

    Deng, Xue-Mei; Xie, Yu

    2012-08-01

    Within the framework of the scalar - tensor theory, its second post - Newtonian (2PN) approximation is obtained by Chandrasekhar ’ s approach. By focusing on an N - point mass system as first step, we reduce the metric to its full 2PN form for light propagation. W e find that although there exist s two parameterized post - Newtonian (PPN) parameters gamma and beta in the 2PN metric, only gamma appears in the 2PN equations of light. As a simple example for applications, a gauge - invariant angle between the directions of two incoming photons for a differential measurement is investigated after the light trajectory is solved in a static and spherically symmetric spacetime. It shows the deviation from the general relativity does not depend on beta even at 2PN level in this circumstance.

  11. Photovoltaic Response from Multilayered Transition Metal Dichalcogenides p-n Junctions

    NASA Astrophysics Data System (ADS)

    Memaran, Shahriar; Pradhan, Nihar; Lu, Zhengguang; Rhodes, Daniel; Ludwig, Jonathan; Zhou, Qiong; Ogunsolu, Omotola; Ajayan, Pulickel; Smirnov, Dmitry; Fernandez-Dominguez, Antonio; Garcia-Vidal, Francisco; Balicas, Luis

    Transition metal dichalcogenides (TMDs) are layered semiconductors with indirect band gaps comparable to Si. These compounds can be grown in large area, while their gap(s) can be tuned by changing their chemical composition or by applying a gate voltage. The experimental evidence collected so far points toward a strong interaction with light, which contrasts with the small photovoltaic efficiencies η <= 1 % extracted from bulk crystals or exfoliated monolayers. Here, we evaluate the potential of these compounds by studying the photovoltaic response of electrostatically generated p-n junctions composed of approximately 10 atomic layers of MoSe2 stacked onto the dielectric h-BN. In addition to ideal diode-like response, we find that these junctions can yield, under AM-1.5 illumination, photovoltaic efficiencies η exceeding 14%, with fill factors of ~ 70 % . Given the available strategies for increasing η such as gap tuning, improving the quality of the electrical contacts, or the fabrication of tandem cells, our study suggests a remarkable potential for photovoltaic applications based on TMDs.

  12. Pronounced Photovoltaic Response from Multilayered Transition-Metal Dichalcogenides PN-Junctions.

    PubMed

    Memaran, Shahriar; Pradhan, Nihar R; Lu, Zhengguang; Rhodes, Daniel; Ludwig, Jonathan; Zhou, Qiong; Ogunsolu, Omotola; Ajayan, Pulickel M; Smirnov, Dmitry; Fernández-Domínguez, Antonio I; García-Vidal, Francisco J; Balicas, Luis

    2015-11-11

    Transition metal dichalcogenides (TMDs) are layered semiconductors with indirect band gaps comparable to Si. These compounds can be grown in large area, while their gap(s) can be tuned by changing their chemical composition or by applying a gate voltage. The experimental evidence collected so far points toward a strong interaction with light, which contrasts with the small photovoltaic efficiencies η ≤ 1% extracted from bulk crystals or exfoliated monolayers. Here, we evaluate the potential of these compounds by studying the photovoltaic response of electrostatically generated PN-junctions composed of approximately 10 atomic layers of MoSe2 stacked onto the dielectric h-BN. In addition to ideal diode-like response, we find that these junctions can yield, under AM-1.5 illumination, photovoltaic efficiencies η exceeding 14%, with fill factors of ~70%. Given the available strategies for increasing η such as gap tuning, improving the quality of the electrical contacts, or the fabrication of tandem cells, our study suggests a remarkable potential for photovoltaic applications based on TMDs. PMID:26513598

  13. Electrically tunable excitonic light-emitting diodes based on monolayer WSe2 p-n junctions

    NASA Astrophysics Data System (ADS)

    Ross, Jason S.; Klement, Philip; Jones, Aaron M.; Ghimire, Nirmal J.; Yan, Jiaqiang; Mandrus, D. G.; Taniguchi, Takashi; Watanabe, Kenji; Kitamura, Kenji; Yao, Wang; Cobden, David H.; Xu, Xiaodong

    2014-04-01

    The development of light-emitting diodes with improved efficiency, spectral properties, compactness and integrability is important for lighting, display, optical interconnect, logic and sensor applications. Monolayer transition-metal dichalcogenides have recently emerged as interesting candidates for optoelectronic applications due to their unique optical properties. Electroluminescence has already been observed from monolayer MoS2 devices. However, the electroluminescence efficiency was low and the linewidth broad due both to the poor optical quality of the MoS2 and to ineffective contacts. Here, we report electroluminescence from lateral p-n junctions in monolayer WSe2 induced electrostatically using a thin boron nitride support as a dielectric layer with multiple metal gates beneath. This structure allows effective injection of electrons and holes, and, combined with the high optical quality of WSe2, yields bright electroluminescence with 1,000 times smaller injection current and 10 times smaller linewidth than in MoS2 (refs 17,18). Furthermore, by increasing the injection bias we can tune the electroluminescence between regimes of impurity-bound, charged and neutral excitons. This system has the required ingredients for new types of optoelectronic device, such as spin- and valley-polarized light-emitting diodes, on-chip lasers and two-dimensional electro-optic modulators.

  14. Electrically Tunable Excitonic Light Emitting Diodes based on Monolayer WSe2 p-n Junctions

    NASA Astrophysics Data System (ADS)

    Ross, Jason; Klement, Philip; Jones, Aaron; Ghimire, Nirmal; Yan, Jiaqiang; Mandrus, David; Taniguchi, Takashi; Watanabe, Kenji; Kitamura, Kenji; Yao, Wang; Cobden, David; Xu, Xiaodong

    2014-03-01

    Light-emitting diodes (LEDs) are of vital importance for lighting, displays, optical interconnects, logic and sensors. The development of new systems that allow improvements in their efficiency, spectral properties, compactness and integrability could have dramatic ramifications. Monolayer transition metal dichalcogenides have recently emerged as interesting candidates for optoelectronic applications due to their unique optical properties. Electroluminescence (EL) has already been observed from monolayer MoS2 devices. However, the EL efficiency was low and the linewidth broad due both to the poor optical quality of MoS2 and ineffective contacts. In this talk, we present EL from lateral p-n junctions in monolayer WSe2 induced electrostatically using a thin boron nitride dielectric layer with multiple metal gates beneath. This structure allows effective injection of electrons and holes, and combined with the high optical quality of WSe2 it yields bright EL with 1000 times smaller injection current and 10 times smaller linewidth than in MoS2. Further, by increasing the injection bias we can tune the EL between regimes of impurity-bound, charged, and neutral excitons. This system has the required ingredients for new kinds of optoelectronic devices such as spin- and valley-polarized LEDs, on-chip lasers, and two-dimensional electro-optic modulators.

  15. Gas Sensors Based on Ceramic p-n Heterocontacts

    SciTech Connect

    Seymen Murat Aygun

    2004-12-19

    Ceramic p-n heterocontacts based on CuO/ZnO were successfully synthesized and a systematic study of their hydrogen sensitivity was conducted. The sensitivity and response rates of CuO/ZnO sensors were studied utilizing current-voltage, current-time, and impedance spectroscopy measurements. The heterocontacts showed well-defined rectifying characteristics and were observed to detect hydrogen via both dc and ac measurements. Surface coverage data were derived from current-time measurements which were then fit to a two-site Langmuir adsorption model quite satisfactorily. The fit suggested that there should be two energetically different adsorption sites in the system. The heterocontacts were doped in an attempt to increase the sensitivity and the response rate of the sensor. First, the effects of doping the p-type (CuO) on the sensor characteristics were investigated. Doping the p-type CuO with both acceptor and isovalent dopants greatly improved the hydrogen sensitivity. The sensitivity of pure heterocontact observed via I-V measurements was increased from {approx}2.3 to {approx}9.4 with Ni doping. Dopants also enhanced the rectifying characteristics of the heterocontacts. Small amounts of Li addition were shown to decrease the reverse bias (saturation) current to 0.2 mA at a bias level of -5V. No unambiguous trends were observed between the sensitivity, the conductivity, and the density of the samples. Comparing the two phase microstructure to the single phase microstructure there was no dramatic increase in the sensitivity. Kinetic studies also confirmed the improved sensor characteristics with doping. The dopants decreased the response time of the sensor by decreasing the response time of one of the adsorption sites. The n-type ZnO was doped with both acceptor and donor dopants. Li doping resulted in the degradation of the p-n junction and the response time of the sensor. However, the current-voltage behavior of Ga-doped heterocontacts showed the best rectifying

  16. Pleurotus nebrodensis polysaccharide (PN-S) enhances the immunity of immunosuppressed mice.

    PubMed

    Cui, Hai-Yan; Wang, Chang-Lu; Wang, Yu-Rong; Li, Zhen-Jing; Chen, Mian-Hua; Li, Feng-Juan; Sun, Yan-Ping

    2015-10-01

    In the present study, the effects of Pleurotus nebrodensis polysaccharide (PN-S) on the immune functions of immunosuppressed mice were determined. The immunosuppressed mouse model was established by treating the mice with cyclophosphamide (40 mg/kg/2d, CY) through intraperitoneal injection. The results showed that PN-S administration significantly reversed the CY-induced weight loss, increased the thymic and splenic indices, and promoted proliferation of T lymphocyte, B lymphocyte, and macrophages. PN-S also enhanced the activity of natural killer cells and increased the immunoglobulin M (IgM) and immunoglobulin G (IgG) levels in the serum. In addition, PN-S treatment significantly increased the phagocytic activity of mouse peritoneal macrophages. PN-S also increased the levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interferon-γ (INF-γ), and nitric oxide (NOS) in splenocytes. qRT-PCR results also indicated that PN-S increased the mRNA expression of IL-6, TNF-α, INF-γ, and nitric oxide synthase (iNOS) in the splenocytes. These results suggest that PN-S treatment enhances the immune function of immunosuppressed mice. This study may provide a basis for the application of this fungus in adjacent immunopotentiating therapy against cancer and in the treatment of chemotherapy-induced immunosuppression. PMID:26481376

  17. Velocity structure of the uppermost mantle beneath East Asia from Pn tomography and its dynamic implications

    NASA Astrophysics Data System (ADS)

    Wang, Suyun; Niu, Fenglin; Zhang, Guomin

    2013-01-01

    AbstractEast Asia is one of the most tectonically active regions on Earth's surface due to the collision from the India plate and the suctions induced by the subduction of the Pacific and Philippine plates. To better understand the complicated deformation and active seismicity of the area, we conducted a <span class="hlt">Pn</span> traveltime tomography to estimate the compressive wave speed of the uppermost mantle beneath East Asia. We collected a total of 296,334 <span class="hlt">Pn</span> arrivals recorded by 1354 stations from 27,777 earthquakes in a rectangular area from 60°E to 145°E in longitude, 15°N to 60°N in latitude. The data set was carefully integrated from three different catalogs after examining potential systematic biases in the catalogs. The inversion results revealed a large-scale velocity perturbation in the study area. <span class="hlt">Pn</span> velocity in the region west to ~108°E is approximately 10% higher than that in the east. In each region, stable blocks tend to have high <span class="hlt">Pn</span> velocity while the boundary regions, which show a high level of seismicity and surface deformation, appear to have low <span class="hlt">Pn</span> velocity. We further computed the Benioff strain rate in the two regions and found it correlates negatively with the averaged <span class="hlt">Pn</span> velocity. Our observations here suggest that <span class="hlt">Pn</span> velocity, which is predominantly determined by Moho temperature, is a good indicator of lithosphere strength.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/pages/biblio/1240617-synthesis-crystal-electronic-structures-pnictides-ae3trpn3-ae-sr-ba-tr-al-ga-pn','SCIGOV-DOEP'); return false;" href="http://www.osti.gov/pages/biblio/1240617-synthesis-crystal-electronic-structures-pnictides-ae3trpn3-ae-sr-ba-tr-al-ga-pn"><span id="translatedtitle">Synthesis, Crystal and Electronic Structures of the Pnictides AE3Tr<span class="hlt">Pn</span>3 (AE = Sr, Ba; Tr = Al, Ga; <span class="hlt">Pn</span> = P, As)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGESBeta</a></p> <p>Stoyko, Stanislav; Voss, Leonard; He, Hua; Bobev, Svilen</p> <p>2015-09-24</p> <p>New ternary arsenides AE3TrAs3 (AE = Sr, Ba; Tr = Al, Ga) and their phosphide analogs Sr3GaP3 and Ba3AlP3 have been prepared by reactions of the respective elements at high temperatures. Single-crystal X-ray diffraction studies reveal that Sr3AlAs3 and Ba3AlAs3 adopt the Ba3AlSb3-type structure (Pearson symbol oC56, space group Cmce, Z = 8). This structure is also realized for Sr3GaP3 and Ba3AlP3. Likewise, the compounds Sr3GaAs3 and Ba3GaAs3 crystallize with the Ba3GaSb3-type structure (Pearson symbol oP56, space group Pnma, Z = 8). Both structures are made up of isolated pairs of edge-shared Al<span class="hlt">Pn</span>4 and Ga<span class="hlt">Pn</span>4 tetrahedra (<span class="hlt">Pn</span> = pnictogen, i.e.,more » P or As), separated by the alkaline-earth Sr2+ and Ba2+ cations. In both cases, there are no homoatomic bonds, hence, regardless of the slightly different atomic arrangements, both structures can be rationalized as valence-precise [AE2+]3[Tr3+][<span class="hlt">Pn</span>3-]3, or rather [AE2+]6[Tr2<span class="hlt">Pn</span>6]12-, i.e., as Zintl phases.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27445860','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27445860"><span id="translatedtitle">Uptake of Plasmin-<span class="hlt">PN</span>-1 Complexes in Early Human Atheroma.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Boukais, Kamel; Bayles, Richard; Borges, Luciano de Figueiredo; Louedec, Liliane; Boulaftali, Yacine; Ho-Tin-Noé, Benoit; Arocas, Véronique; Bouton, Marie-Christine; Michel, Jean-Baptiste</p> <p>2016-01-01</p> <p>Zymogens are delivered to the arterial wall by radial transmural convection. Plasminogen can be activated within the arterial wall to produce plasmin, which is involved in evolution of the atherosclerotic plaque. Vascular smooth muscle cells (vSMCs) protect the vessels from proteolytic injury due to atherosclerosis development by highly expressing endocytic LDL receptor-related protein-1 (LRP-1), and by producing anti-proteases, such as Protease Nexin-1 (<span class="hlt">PN</span>-1). <span class="hlt">PN</span>-1 is able to form covalent complexes with plasmin. We hypothesized that plasmin-<span class="hlt">PN</span>-1 complexes could be internalized via LRP-1 by vSMCs during the early stages of human atheroma. LRP-1 is also responsible for the capture of aggregated LDL in human atheroma. Plasmin activity and immunohistochemical analyses of early human atheroma showed that the plasminergic system is activated within the arterial wall, where intimal foam cells, including vSMCs and platelets, are the major sites of <span class="hlt">PN</span>-1 accumulation. Both <span class="hlt">PN</span>-1 and LRP-1 are overexpressed in early atheroma at both messenger and protein levels. Cell biology studies demonstrated an increased expression of <span class="hlt">PN</span>-1 and tissue plasminogen activator by vSMCs in response to LDL. Plasmin-<span class="hlt">PN</span>-1 complexes are internalized via LRP-1 in vSMCs, whereas plasmin alone is not. Tissue <span class="hlt">PN</span>-1 interacts with plasmin in early human atheroma via two complementary mechanisms: plasmin inhibition and tissue uptake of plasmin-<span class="hlt">PN</span>-1 complexes via LRP-1 in vSMCs. Despite this potential protective effect, plasminogen activation by vSMCs remains abnormally elevated in the intima in early stages of human atheroma. PMID:27445860</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4927630','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4927630"><span id="translatedtitle">Uptake of Plasmin-<span class="hlt">PN</span>-1 Complexes in Early Human Atheroma</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Boukais, Kamel; Bayles, Richard; Borges, Luciano de Figueiredo; Louedec, Liliane; Boulaftali, Yacine; Ho-Tin-Noé, Benoit; Arocas, Véronique; Bouton, Marie-Christine; Michel, Jean-Baptiste</p> <p>2016-01-01</p> <p>Zymogens are delivered to the arterial wall by radial transmural convection. Plasminogen can be activated within the arterial wall to produce plasmin, which is involved in evolution of the atherosclerotic plaque. Vascular smooth muscle cells (vSMCs) protect the vessels from proteolytic injury due to atherosclerosis development by highly expressing endocytic LDL receptor-related protein-1 (LRP-1), and by producing anti-proteases, such as Protease Nexin-1 (<span class="hlt">PN</span>-1). <span class="hlt">PN</span>-1 is able to form covalent complexes with plasmin. We hypothesized that plasmin-<span class="hlt">PN</span>-1 complexes could be internalized via LRP-1 by vSMCs during the early stages of human atheroma. LRP-1 is also responsible for the capture of aggregated LDL in human atheroma. Plasmin activity and immunohistochemical analyses of early human atheroma showed that the plasminergic system is activated within the arterial wall, where intimal foam cells, including vSMCs and platelets, are the major sites of <span class="hlt">PN</span>-1 accumulation. Both <span class="hlt">PN</span>-1 and LRP-1 are overexpressed in early atheroma at both messenger and protein levels. Cell biology studies demonstrated an increased expression of <span class="hlt">PN</span>-1 and tissue plasminogen activator by vSMCs in response to LDL. Plasmin-<span class="hlt">PN</span>-1 complexes are internalized via LRP-1 in vSMCs, whereas plasmin alone is not. Tissue <span class="hlt">PN</span>-1 interacts with plasmin in early human atheroma via two complementary mechanisms: plasmin inhibition and tissue uptake of plasmin-<span class="hlt">PN</span>-1 complexes via LRP-1 in vSMCs. Despite this potential protective effect, plasminogen activation by vSMCs remains abnormally elevated in the intima in early stages of human atheroma. PMID:27445860</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_6 --> <div id="page_7" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="121"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22395622','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22395622"><span id="translatedtitle">Titanium-dioxide nanotube <span class="hlt">p-n</span> homojunction diode</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Alivov, Yahya E-mail: pnagpal@colorado.edu; Ding, Yuchen; Singh, Vivek; Nagpal, Prashant E-mail: pnagpal@colorado.edu</p> <p>2014-12-29</p> <p>Application of semiconductors in functional optoelectronic devices requires precise control over their doping and formation of junction between p- and n-doped semiconductors. While doped thin films have led to several semiconductor devices, need for high-surface area nanostructured devices for photovoltaic, photoelectrochemical, and photocatalytic applications has been hindered by lack of desired doping in nanostructures. Here, we show titanium-dioxide (TiO{sub 2}) nanotubes doped with nitrogen (N) and niobium (Nb) as acceptors and donors, respectively, and formation of TiO{sub 2} nanotubes <span class="hlt">p-n</span> homojunction. This TiO{sub 2}:N/TiO{sub 2}:Nb homojunction showed distinct diode-like behaviour with rectification ratio of 1115 at ±5 V and exhibited good photoresponse for ultraviolet light (λ = 365 nm) with sensitivity of 0.19 A/W at reverse bias of −5 V. These results can have important implications for development of nanostructured metal-oxide solar-cells, photodiodes, LED's, photocatalysts, and photoelectrochemical devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21055020','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21055020"><span id="translatedtitle">Background Studies for the <span class="hlt">pn</span>-CCD Detector of CAST</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Rodriguez, A.; Beltran, B.; Cebrian, S.; Gomez, H.; Irastorza, I. G.; Luzon, G.; Morales, J.; Ruz, J.; Villar, J. A.; Hartmann, R.; Kotthaus, R.; Klose, C.; Kuster, M.; Strueder, L.</p> <p>2007-03-28</p> <p>The CERN Axion Solar Telescope (CAST) experiment searches for axions from the Sun converted into photons with energies up to around 10 keV via the inverse Primakoff effect in the high magnetic field of a superconducting Large Hadron Collider (LHC) prototype magnet. A backside illuminated <span class="hlt">pn</span>-CCD detector in conjunction with an X-ray mirror optics is one of the three detectors used in CAST to register the expected photon signal. Since this signal is very rare a detailed study of the detector background has been undertaken with the aim to understand and further reduce the background level of the detector. The analysis is based on measured data taken during the data taking period of 2003 and 2004 of CAST and on Monte Carlo simulations of background with different origin. The background study performed for this detector show that the level of background (8.00{+-}0.07)x10-5 counts cm-2 s-1 keV-1 between 1 and 7 keV is dominated by the external gamma background due to natural activities at the experimental site, while radioactive impurities in the detector itself and cosmic neutrons contribute with a smaller fraction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014ApPhL.105z3501A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014ApPhL.105z3501A"><span id="translatedtitle">Titanium-dioxide nanotube <span class="hlt">p-n</span> homojunction diode</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alivov, Yahya; Ding, Yuchen; Singh, Vivek; Nagpal, Prashant</p> <p>2014-12-01</p> <p>Application of semiconductors in functional optoelectronic devices requires precise control over their doping and formation of junction between p- and n-doped semiconductors. While doped thin films have led to several semiconductor devices, need for high-surface area nanostructured devices for photovoltaic, photoelectrochemical, and photocatalytic applications has been hindered by lack of desired doping in nanostructures. Here, we show titanium-dioxide (TiO2) nanotubes doped with nitrogen (N) and niobium (Nb) as acceptors and donors, respectively, and formation of TiO2 nanotubes <span class="hlt">p-n</span> homojunction. This TiO2:N/TiO2:Nb homojunction showed distinct diode-like behaviour with rectification ratio of 1115 at ±5 V and exhibited good photoresponse for ultraviolet light (λ = 365 nm) with sensitivity of 0.19 A/W at reverse bias of -5 V. These results can have important implications for development of nanostructured metal-oxide solar-cells, photodiodes, LED's, photocatalysts, and photoelectrochemical devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1983PhDT........94P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1983PhDT........94P"><span id="translatedtitle">Chaotic Behaviour of a Driven <span class="hlt">P-N</span> Junction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Perez, Jose Maria</p> <p></p> <p>The chaotic behavior of a driven <span class="hlt">p-n</span> junction is experimentally examined. Bifurcation diagrams for the system are measured, showing period doubling bifurcations up to f/32, onset of chaos, reverse bifurcations of chaotic bands, and periodic windows. Some of the measured bifurcation diagrams are similar to the bifurcation diagram of the logistic map x(,n+1) = (lamda)x(,n)(1 - x(,n)). A return map is also measured showing approximately a one-dimensional map with a single extremum at low driving voltages. The intermittency route to chaos is experimentally observed to occur near a tangent bifurcation as the system approaches a period 5 window at (lamda) = (lamda)(,5). Data are presented for the dependence of the average laminar length <l> on (epsilon) = (lamda)(,5) - (lamda), and for the probability distribution P(l) vs. l. The effects of additive stochastic noise on period doubling, chaos, windows, and intermittency are examined and are found to agree with the logistic model and universal predictions. Three examples of crisis of the attractor are observed. The crises occur when an unstable orbit intersects the chaotic attractor. A period adding sequence is reported in which wide periodic windows of period 2, 3, 4, ... are observed for increasing driving voltage. The initial period doubling cascade and the period adding sequence are compared to two theoretical models, with reasonable success.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004A%26A...422..563S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004A%26A...422..563S"><span id="translatedtitle">Me 1-1: A <span class="hlt">PN</span> containing a cool star</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shen, Z.-X.; Liu, X.-W.; Danziger, I. J.</p> <p>2004-08-01</p> <p>We report the detection of a cool stellar component at the center of the planetary nebula (<span class="hlt">PN</span>) Me 1-1 and present optical spectra of the system. From measurements of nebular emission lines, we have derived electron temperature, density and chemical composition. Heavy elemental abundances deduced from collisionally excited lines (CELs) are compared with those derived from optical recombination lines (ORLs). The electron temperature and density deduced from the nebular analysis were used to calculate the nebular continuum emission, which was then subtracted from the observed spectrum in order to obtain the spectrum of the cool stellar component apparent in the observed spectrum. We calculate B and V magnitudes of the cool companion and obtain a color index of B-V=1.20. By comparing the spectrum of the cool star with standard spectra in Pickles's 1998 Stellar Flux Library, we find that the cool component has the spectral type of a K3-4 bright giant. Our analysis suggests that Me 1-1 is probably a yellow symbiotic system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20010012167&hterms=E-LAYER&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DE-LAYER','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20010012167&hterms=E-LAYER&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DE-LAYER"><span id="translatedtitle"><span class="hlt">p-n</span> Junction Diodes Fabricated on Si-Si/Ge Heteroepitaxial Films</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Das, K.; Mazumder, M. D. A.; Hall, H.; Alterovitz, Samuel A. (Technical Monitor)</p> <p>2000-01-01</p> <p>A set of photolithographic masks was designed for the fabrication of diodes in the Si-Si/Ge material system. Fabrication was performed on samples obtained from two different wafers: (1) a complete HBT structure with an n (Si emitter), p (Si/Ge base), and an n/n+ (Si collector/sub-collector) deposited epitaxially (MBE) on a high resistivity p-Si substrate, (2) an HBT structure where epitaxial growth was terminated after the p-type base (Si/Ge) layer deposition. Two different process runs were attempted for the fabrication of Si-Si/Ge (n-p) and Si/Ge-Si (<span class="hlt">p-n</span>) junction diodes formed between the emitter-base and base-collector layers, respectively, of the Si-Si/Ge-Si HBT structure. One of the processes employed a plasma etching step to expose the p-layer in the structure (1) and to expose the e-layer in structure (2). The Contact metallization used for these diodes was a Cu-based metallization scheme that was developed during the first year of the grant. The plasma-etched base-collector diodes on structure (2) exhibited well-behaved diode-like characteristics. However, the plasma-etched emitter-base diodes demonstrated back-to-back diode characteristics. These back-to back characteristics were probably due to complete etching of the base-layer, <span class="hlt">yielding</span> a p-n-p diode. The deep implantation process <span class="hlt">yielded</span> rectifying diodes with asymmetric forward and reverse characteristics. The ideality factor of these diodes were between 1.6 -2.1, indicating that the quality of the MBE grown epitaxial films was not sufficiently high, and also incomplete annealing of the implantation damage. Further study will be conducted on CVD grown films, which are expected to have higher epitaxial quality.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22275613','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22275613"><span id="translatedtitle">Magnetic electron focusing and tuning of the electron current with a <span class="hlt">pn</span>-junction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Milovanović, S. P. Ramezani Masir, M. Peeters, F. M.</p> <p>2014-01-28</p> <p>Transverse magnetic focusing properties of graphene using a ballistic four terminal structure are investigated. The electric response is obtained using the semiclassical billiard model. The transmission exhibits pronounced peaks as a consequence of skipping orbits at the edge of the structure. When we add a <span class="hlt">pn</span>-junction between the two probes, snake states along the <span class="hlt">pn</span>-interface appear. Injected electrons are guided by the <span class="hlt">pn</span>-interface to one of the leads depending on the value of the applied magnetic field. Oscillations in the resistance are found depending on the amount of particles that end up in each lead.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JAP...115d3719M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JAP...115d3719M"><span id="translatedtitle">Magnetic electron focusing and tuning of the electron current with a <span class="hlt">pn</span>-junction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Milovanović, S. P.; Ramezani Masir, M.; Peeters, F. M.</p> <p>2014-01-01</p> <p>Transverse magnetic focusing properties of graphene using a ballistic four terminal structure are investigated. The electric response is obtained using the semiclassical billiard model. The transmission exhibits pronounced peaks as a consequence of skipping orbits at the edge of the structure. When we add a <span class="hlt">pn</span>-junction between the two probes, snake states along the <span class="hlt">pn</span>-interface appear. Injected electrons are guided by the <span class="hlt">pn</span>-interface to one of the leads depending on the value of the applied magnetic field. Oscillations in the resistance are found depending on the amount of particles that end up in each lead.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22278085','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22278085"><span id="translatedtitle">Many-body effects on optical gain in GaAs<span class="hlt">PN/GaPN</span> quantum well lasers for silicon integration</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Park, Seoung-Hwan</p> <p>2014-02-14</p> <p>Many-body effects on the optical gain in GaAs<span class="hlt">PN</span>/GaP QW structures were investigated by using the multiband effective-mass theory and the non-Markovian gain model with many-body effects. The free-carrier model shows that the optical gain peak slightly increases with increasing N composition. In addition, the QW structure with a larger As composition shows a larger optical gain than that with a smaller As composition. On the other hand, in the case of the many-body model, the optical gain peak decreases with increasing N composition. Also, the QW structure with a smaller As composition is observed to have a larger optical gain than that with a larger As composition. This can be explained by the fact that the QW structure with a smaller As or N composition shows a larger Coulomb enhancement effect than that with a larger As or N composition. This means that it is important to consider the many-body effect in obtaining guidelines for device design issues.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19780047822&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DP-n%2Bjunction','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19780047822&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DP-n%2Bjunction"><span id="translatedtitle">Experimental determination of series resistance of <span class="hlt">p-n</span> junction diodes and solar cells</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chen, P. J.; Pao, S. C.; Neugroschel, A.; Lindholm, F. A.</p> <p>1978-01-01</p> <p>Various methods for determining the series resistance of <span class="hlt">p-n</span> junction diodes and solar cells are described and compared. New methods involving the measurement of the ac admittance are shown to have certain advantages over methods proposed earlier.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4124210','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4124210"><span id="translatedtitle">Part-Based Visual Tracking via Online Weighted <span class="hlt">P-N</span> Learning</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Fan, Heng; Xiang, Jinhai; Xu, Jun</p> <p>2014-01-01</p> <p>We propose a novel part-based tracking algorithm using online weighted <span class="hlt">P-N</span> learning. An online weighted <span class="hlt">P-N</span> learning method is implemented via considering the weight of samples during classification, which improves the performance of classifier. We apply weighted <span class="hlt">P-N</span> learning to track a part-based target model instead of whole target. In doing so, object is segmented into fragments and parts of them are selected as local feature blocks (LFBs). Then, the weighted <span class="hlt">P-N</span> learning is employed to train classifier for each local feature block (LFB). Each LFB is tracked through the corresponding classifier, respectively. According to the tracking results of LFBs, object can be then located. During tracking process, to solve the issues of occlusion or pose change, we use a substitute strategy to dynamically update the set of LFB, which makes our tracker robust. Experimental results demonstrate that the proposed method outperforms the state-of-the-art trackers. PMID:25133228</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20060030668&hterms=quirk&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dquirk','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20060030668&hterms=quirk&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dquirk"><span id="translatedtitle">Analysis of sampling and quantization effects on the performance of <span class="hlt">PN</span> code tracking loops</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Quirk, K. J.; Srinivasan, M.</p> <p>2002-01-01</p> <p>Pseudonoise (<span class="hlt">PN</span>) code tracking loops in direct-sequence spread-spectrum systems are often implemented using digital hardware. Performance degradation due to quantization and sampling effects is not adequately characterized by the traditional analog system feedback loop analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22303906','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22303906"><span id="translatedtitle">Imaging the <span class="hlt">p-n</span> junction in a gallium nitride nanowire with a scanning microwave microscope</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Imtiaz, Atif; Wallis, Thomas M.; Brubaker, Matt D.; Blanchard, Paul T.; Bertness, Kris A.; Sanford, Norman A.; Kabos, Pavel; Weber, Joel C.; Coakley, Kevin J.</p> <p>2014-06-30</p> <p>We used a broadband, atomic-force-microscope-based, scanning microwave microscope (SMM) to probe the axial dependence of the charge depletion in a <span class="hlt">p-n</span> junction within a gallium nitride nanowire (NW). SMM enables the visualization of the <span class="hlt">p-n</span> junction location without the need to make patterned electrical contacts to the NW. Spatially resolved measurements of S{sub 11}{sup ′}, which is the derivative of the RF reflection coefficient S{sub 11} with respect to voltage, varied strongly when probing axially along the NW and across the <span class="hlt">p-n</span> junction. The axial variation in S{sub 11}{sup ′}  effectively mapped the asymmetric depletion arising from the doping concentrations on either side of the junction. Furthermore, variation of the probe tip voltage altered the apparent extent of features associated with the <span class="hlt">p-n</span> junction in S{sub 11}{sup ′} images.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22261921','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22261921"><span id="translatedtitle">Homojunction <span class="hlt">p-n</span> photodiodes based on As-doped single ZnO nanowire</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cho, H. D.; Zakirov, A. S.; Yuldashev, Sh. U.; Kang, T. W.; Ahn, C. W.; Yeo, Y. K.</p> <p>2013-12-04</p> <p>Photovoltaic device was successfully grown solely based on the single ZnO <span class="hlt">p-n</span> homojunction nanowire. The ZnO nanowire <span class="hlt">p-n</span> diode consists of an as-grown n-type segment and an in-situ arsenic doped p-type segment. This <span class="hlt">p-n</span> homojunction acts as a good photovoltaic cell, producing a photocurrent almost 45 times larger than the dark current under reverse-biased condition. Our results demonstrate that present ZnO <span class="hlt">p-n</span> homojunction nanowire can be used as a self-powered ultraviolet photodetector as well as a photovoltaic cell, which can also be used as an ultralow electrical power source for nano-scale electronic, optoelectronic, and medical devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/12570411','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/12570411"><span id="translatedtitle">n-p short-range correlations from (p,2<span class="hlt">p+n</span>) measurements.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tang, A; Watson, J W; Aclander, J; Alster, J; Asryan, G; Averichev, Y; Barton, D; Baturin, V; Bukhtoyarova, N; Carroll, A; Gushue, S; Heppelmann, S; Leksanov, A; Makdisi, Y; Malki, A; Minina, E; Navon, I; Nicholson, H; Ogawa, A; Panebratsev, Yu; Piasetzky, E; Schetkovsky, A; Shimanskiy, S; Zhalov, D</p> <p>2003-01-31</p> <p>We studied the 12C(p,2<span class="hlt">p+n</span>) reaction at beam momenta of 5.9, 8.0, and 9.0 GeV/c. For quasielastic (p,2p) events p(f), the momentum of the knocked-out proton before the reaction, was compared (event by event) with <span class="hlt">p(n</span>), the coincident neutron momentum. For |p(n)|>k(F)=0.220 GeV/c (the Fermi momentum) a strong back-to-back directional correlation between p(f) and <span class="hlt">p(n</span>) was observed, indicative of short-range n-p correlations. From <span class="hlt">p(n</span>) and p(f) we constructed the distributions of c.m. and relative motion in the longitudinal direction for correlated pairs. We also determined that 49+/-13% of events with |p(f)|>k(F) had directionally correlated neutrons with |p(n)|>k(F). PMID:12570411</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2013aero.confE.170J&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2013aero.confE.170J&link_type=ABSTRACT"><span id="translatedtitle">Regenerative <span class="hlt">PN</span> ranging experience with New Horizons during 2012</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jensen, J. R.; Haskins, C. B.; DeBoy, C. C.</p> <p></p> <p>The New Horizons mission to Pluto is the first deep space mission to include the capability of supporting regenerative <span class="hlt">PN</span> ranging. During the current phase of the mission, sequential tone ranging supports the mission navigation requirements but regenerative ranging will expand the conditions (antenna selection, integration time, etc.) over which ranging will be successful during any extended mission following the Pluto fly-by, to objects in the Kuiper belt. Experience with regenerative ranging is being obtained now in preparation for its use in an extended mission. During most of 2012, New Horizons was in a hibernation state. Tracking was conducted between late April and early July. Six regenerative ranging passes were performed to bookend this interval; 2 at the beginning and 4 at the end. During that time, the distance between the spacecraft and Earth was in excess of 22 Astronautical Units (AU) and the Pr/No levels were below 15 dB-Hz. A seventh regenerative ranging pass was performed in May at a higher signal level in order to test the acquisition of the ranging code by the spacecraft during a variety of conditions. The consistency of the regenerative range measurements with the adjacent sequential tone ranging measurements has been demonstrated and serves as a check on the calibration of the regenerative ranging system conditions. The range measurement precision has been shown to follow the predictions that are based on the uplink and downlink signal power. The regenerative ranging system has been shown to acquire the uplink ranging code with and without a commanded reset and regardless of the noise bandwidth setting of the system. This paper will present the data that was obtained during 2012 and will describe the analysis results for the regenerative ranging experience during 2012.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MARL17001L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MARL17001L"><span id="translatedtitle">Properties of Edge States at the Graphene <span class="hlt">P-N</span> Junction Interface</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Le, Son; Klimov, Nikolai; Newell, David; Yan, Jun; Lee, Ji Ung; Richter, Curt</p> <p></p> <p>The Landau level edge states from the p- and the n-section of a graphene <span class="hlt">P/N</span> junction (<span class="hlt">pn</span>J) interact with each other differently across the junction depending upon the properties of the junction and the graphene. Full equilibration was reported for a two terminal graphene <span class="hlt">pn</span>J device in Williams et al.. In our four-terminal device, however, only the lowest Landau level edge state is equilibrated across the <span class="hlt">pn</span>J. When the two devices are compared, the LL energy spacings, the length of the edge states along the <span class="hlt">pn</span>J interface, and the carrier mobility are similar. Electrostatic simulations for our device geometry and that of contrast the rate of change of the electrostatic potential across the <span class="hlt">pn</span>Js. Edge states at an electrostatically smooth junction are spatially further apart than those at a relatively abrupt junction, which decreases the probability of edge states mixing. Thus, we attribute the difference in equilibration in our device and that of to the dramatic difference in the shape of the electrostatic junction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19880024433&hterms=Phosphorus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DPhosphorus','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19880024433&hterms=Phosphorus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DPhosphorus"><span id="translatedtitle">Detection of interstellar <span class="hlt">PN</span> - The first phosphorus-bearing species observed in molecular clouds</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ziurys, L. M.</p> <p>1987-01-01</p> <p>Phosphorus nitride (<span class="hlt">PN</span>) has been detected in the interstellar medium. The J = 2-1, 3-2, 5-4, and 6-5 rotational lines of this species have been observed toward Orion-KL, and the J = 2-1 transition in Sgr B2 and W51. The <span class="hlt">PN</span> line profiles in Orion indicate that the molecule's emission arises from the 'plateau' or 'doughnut' region associated with the outflow from IRc2. The species is thus primarily present in hot, dense gas. Column densities derived for <span class="hlt">PN</span> toward Orion-KL are (3-4) x 10 to the 13th/sq cm, but may be as high as 10 to the 14th/sq cm, if the species is located in a 10-arcsec region. These column densities imply a fractional abundance for <span class="hlt">PN</span> in the Orion 'plateau' of (1-4) x 10 to the -10th. Such a large abundance for <span class="hlt">PN</span> is not predicted by quiescent cloud ion-molecule chemistry and suggests that high-temperature processes are responsible for the synthesis of <span class="hlt">PN</span> in the KL outflow.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24608231','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24608231"><span id="translatedtitle">Optoelectronic devices based on electrically tunable <span class="hlt">p-n</span> diodes in a monolayer dichalcogenide.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Baugher, Britton W H; Churchill, Hugh O H; Yang, Yafang; Jarillo-Herrero, Pablo</p> <p>2014-04-01</p> <p>The <span class="hlt">p-n</span> junction is the functional element of many electronic and optoelectronic devices, including diodes, bipolar transistors, photodetectors, light-emitting diodes and solar cells. In conventional <span class="hlt">p-n</span> junctions, the adjacent p- and n-type regions of a semiconductor are formed by chemical doping. Ambipolar semiconductors, such as carbon nanotubes, nanowires and organic molecules, allow for <span class="hlt">p-n</span> junctions to be configured and modified by electrostatic gating. This electrical control enables a single device to have multiple functionalities. Here, we report ambipolar monolayer WSe2 devices in which two local gates are used to define a <span class="hlt">p-n</span> junction within the WSe2 sheet. With these electrically tunable <span class="hlt">p-n</span> junctions, we demonstrate both <span class="hlt">p-n</span> and n-p diodes with ideality factors better than 2. Under optical excitation, the diodes demonstrate a photodetection responsivity of 210 mA W(-1) and photovoltaic power generation with a peak external quantum efficiency of 0.2%, promising values for a nearly transparent monolayer material in a lateral device geometry. Finally, we demonstrate a light-emitting diode based on monolayer WSe2. These devices provide a building block for ultrathin, flexible and nearly transparent optoelectronic and electronic applications based on ambipolar dichalcogenide materials. PMID:24608231</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JGRB..11610311P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JGRB..11610311P"><span id="translatedtitle">Tomographic <span class="hlt">Pn</span> and Sn velocity beneath the continental collision zone from Alps to Himalaya</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pei, Shunping; Sun, Youshun; ToksöZ, M. Nafi</p> <p>2011-10-01</p> <p>We have obtained Vp and Vs velocity images of the uppermost mantle beneath the continental collision zone from the Alps to the Himalaya by performing tomographic inversion using both <span class="hlt">Pn</span> and Sn travel times. 654,999 <span class="hlt">Pn</span> arrivals and 121,838 Sn arrivals were selected from the joint database including ISC/EHB, Iran bulletin and the Annual Bulletin of Chinese Earthquakes. Average <span class="hlt">Pn</span> and Sn velocities are 8.04 km/s and 4.60 km/s, respectively, and maximum velocity perturbations are about 6%. <span class="hlt">Pn</span> velocity correlates well with topography. In general, mountains, with high elevations, show low velocity, while the seas, basins and plains with low elevations show high velocity because the mountains are collision zones with strong tectonic activity and the low elevation areas are stable plates. The large tectonic lines are boundaries between high and low <span class="hlt">Pn</span> velocity, such as plate boundaries, sutures and faults between plates and orogens. Sn velocity shows a very similar pattern to <span class="hlt">Pn</span> velocity. A geodynamic cartoon is proposed to show the relationship between velocity and tectonics, indicating that the sutures are boundaries with high dip angles and the plate boundaries are low angle reverse faults in the region.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_7 --> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1240617','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1240617"><span id="translatedtitle">Synthesis, Crystal and Electronic Structures of the Pnictides AE<sub>3</sub>Tr<span class="hlt">Pn</span><sub>3</sub> (AE = Sr, Ba; Tr = Al, Ga; <span class="hlt">Pn</span> = P, As)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Stoyko, Stanislav; Voss, Leonard; He, Hua; Bobev, Svilen</p> <p>2015-09-24</p> <p>New ternary arsenides AE<sub>3</sub>TrAs<sub>3</sub> (AE = Sr, Ba; Tr = Al, Ga) and their phosphide analogs Sr<sub>3</sub>GaP<sub>3</sub> and Ba<sub>3</sub>AlP<sub>3</sub> have been prepared by reactions of the respective elements at high temperatures. Single-crystal X-ray diffraction studies reveal that Sr<sub>3</sub>AlAs<sub>3</sub> and Ba<sub>3</sub>AlAs<sub>3</sub> adopt the Ba<sub>3</sub>AlSb<sub>3</sub>-type structure (Pearson symbol oC56, space group Cmce, Z = 8). This structure is also realized for Sr<sub>3</sub>GaP<sub>3</sub> and Ba<sub>3</sub>AlP<sub>3</sub>. Likewise, the compounds Sr<sub>3</sub>GaAs<sub>3</sub> and Ba<sub>3</sub>GaAs<sub>3</sub> crystallize with the Ba<sub>3</sub>GaSb<sub>3</sub>-type structure (Pearson symbol oP56, space group Pnma, Z = 8). Both structures are made up of isolated pairs of edge-shared Al<span class="hlt">Pn</span><sub>4</sub> and Ga<span class="hlt">Pn</span><sub>4</sub> tetrahedra (<span class="hlt">Pn</span> = pnictogen, i.e., P or As), separated by the alkaline-earth Sr<sup>2+</sup> and Ba<sup>2+</sup> cations. In both cases, there are no homoatomic bonds, hence, regardless of the slightly different atomic arrangements, both structures can be rationalized as valence-precise [AE<sup>2+</sup>]<sub>3</sub>[Tr<sup>3+</sup>][<span class="hlt">Pn</span><sup>3-</sup>]<sub>3</sub>, or rather [AE<sup>2+</sup>]<sub>6</sub>[Tr<sub>2</sub><span class="hlt">Pn</span><sub>6</sub>]<sup>12-</sup>, i.e., as Zintl phases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/21241681','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/21241681"><span id="translatedtitle">Olivary climbing fiber alterations in <span class="hlt">PN</span>40 rat cerebellum following postnatal ethanol exposure.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pierce, Dwight R; Hayar, Abdallah; Williams, D Keith; Light, Kim Edward</p> <p>2011-03-10</p> <p>Developmental ethanol exposure in rats during postnatal days (<span class="hlt">PN</span>) 4-6 is known to cause significant loss of the cerebellar Purkinje cells. It is not known what happens to the surviving neurons as they continue to develop. This study was designed to quantify the interactions between the olivary climbing fibers and the Purkinje cells when the cerebellar circuits have matured. Rat pups were treated with a daily dose of ethanol (4.5g/kg body weight) delivered by intragastric intubation on <span class="hlt">PN</span>4, <span class="hlt">PN</span>4-6, or <span class="hlt">PN</span>7-9. The interactions between the climbing fibers and the Purkinje cells were examined on <span class="hlt">PN</span>40 using confocal microscopy. Mid-vermal cerebellar sections were stained with antibodies to calbindin-D28k (to visualize Purkinje cells) and vesicular glutamate transporter 2 (VGluT2, to visualize climbing fibers). Confocal z-stack images were obtained from Lobule 1 and analyzed with Imaris software to quantify the staining of the two antibodies. The VGluT2 immunostaining was significantly reduced and this was associated with alterations in the synaptic integrity, and synaptic number per Purkinje cell with only a single exposure on <span class="hlt">PN</span>4 enough to cause the alterations. Previously, we demonstrated similar deficits in climbing fiber innervation when analyzed on <span class="hlt">PN</span>14 (Pierce, Hayar, Williams, and Light, 2010). The present study confirms that these alterations are sustained and further identifies the decreased synaptic density as well as alterations to the general morphology of the molecular layer of the cerebellar cortex that are the result of the binge ethanol exposure. PMID:21241681</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006NIMPA.565..251M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006NIMPA.565..251M"><span id="translatedtitle"><span class="hlt">pn</span>CCD for photon detection from near-infrared to X-rays</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meidinger, Norbert; Andritschke, Robert; Hartmann, Robert; Herrmann, Sven; Holl, Peter; Lutz, Gerhard; Strüder, Lothar</p> <p>2006-09-01</p> <p>A <span class="hlt">pn</span>CCD is a special type of charge-coupled device developed for spectroscopy and imaging of X-rays with high time resolution and quantum efficiency. Its most famous application is the operation on the XMM-Newton satellite, an X-ray astronomy mission that was launched by the European space agency in 1999. The excellent performance of the focal plane camera has been maintained for more than 6 years in orbit. The energy resolution in particular has shown hardly any degradation since launch. In order to satisfy the requirements of future X-ray astronomy missions as well as those of ground-based experiments, a new type of <span class="hlt">pn</span>CCD has been developed. This ‘frame-store <span class="hlt">pn</span>CCD’ shows an enhanced performance compared to the XMM-Newton type of <span class="hlt">pn</span>CCD. Now, more options in device design and operation are available to tailor the detector to its respective application. Part of this concept is a programmable analog signal processor, which has been developed for the readout of the CCD signals. The electronic noise of the new detector has a value of only 2 electrons equivalent noise charge (ENC), which is less than half of the figure achieved for the XMM-Newton-type <span class="hlt">pn</span>CCD. The energy resolution for the Mn-Kα line at 5.9 keV is approximately 130 eV FWHM. We have close to 100% quantum efficiency for both low- and high-energy photon detection (e.g. the C-K line at 277 eV, and the Ge-Kα line at 10 keV, respectively). Very high frame rates of 1000 images/s have been achieved due to the ultra-fast readout accomplished by the parallel architecture of the <span class="hlt">pn</span>CCD and the analog signal processor. Excellent spectroscopic performance is shown even at the relatively high operating temperature of -25 °C that can be achieved by a Peltier cooler. The applications of the low-noise and fast <span class="hlt">pn</span>CCD detector are not limited to the detection of X-rays. With an anti-reflective coating deposited on the photon entrance window, we achieve high quantum efficiency also for near-infrared and optical</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EaSci..25..485F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EaSci..25..485F"><span id="translatedtitle"><span class="hlt">Pn</span> wave velocity and anisotropy beneath Pamir and its adjacent regions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Feng, Biao; Pei, Shunping</p> <p>2012-12-01</p> <p>As the western end point of continental collision between the Indian and Eurasian plates, Pamir is an ideal place to research uplifting mechanisms in the Tibetan plateau. In this study, 141 644 <span class="hlt">Pn</span> arrivals were used to obtain seismic wave velocities and anisotropy in the uppermost mantle beneath Pamir and its adjacent regions by performing tomographic inversion of <span class="hlt">Pn</span> travel times. The data were selected from multiple databases, including ISC/EHB, the Annual Bulletin of Chinese Earthquakes, and regional bulletins of Xinjiang. The tomography results reveal significant features with high resolution and correlate well with geological structures. The main results are as follows: (1) The <span class="hlt">Pn</span> wave velocities are particularly high in the old stable blocks such as Tarim basin, Indian plate and Tajik basin, while the low <span class="hlt">Pn</span> velocities always lie in tectonically active regions like the western Tibetan plateau, Pamir, Tianshan and Hindu Kush. (2) Strong <span class="hlt">Pn</span> anisotropy is found beneath the Indian-Eurasian collision zone; its direction is parallel to the collision arc and nearly perpendicular to both the direction of maximum compression stress and relative crustal movement. The result is probably caused by the pure shear deformation in the uppermost mantle of the collision zone. (3) A geodynamic continent-continent collision model is proposed to show anisotropy and collision mechanisms between the Indian plate and the Tarim and Tajik basins.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22131138','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22131138"><span id="translatedtitle">Ternary CaCu{sub 4}P{sub 2}-type pnictides AAg{sub 4}<span class="hlt">Pn</span>{sub 2} (A=Sr, Eu; <span class="hlt">Pn</span>=As, Sb)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Stoyko, Stanislav S.; Khatun, Mansura; Scott Mullen, C.; Mar, Arthur</p> <p>2012-08-15</p> <p>Four ternary pnictides AAg{sub 4}<span class="hlt">Pn</span>{sub 2} (A=Sr, Eu; <span class="hlt">Pn</span>=As, Sb) were prepared by reactions of the elements at 850 Degree-Sign C and their crystal structures were determined from single-crystal X-ray diffraction studies. These silver-containing pnictides AAg{sub 4}<span class="hlt">Pn</span>{sub 2} adopt the trigonal CaCu{sub 4}P{sub 2}-type structure (Pearson symbol hR21, space group R3-bar m, Z=3; a=4.5555(6) A, c=24.041(3) A for SrAg{sub 4}As{sub 2}; a=4.5352(2) A, c=23.7221(11) A for EuAg{sub 4}As{sub 2}; a=4.7404(4) A, c=25.029(2) A for SrAg{sub 4}Sb{sub 2}; a=4.7239(3) A, c=24.689(2) A for EuAg{sub 4}Sb{sub 2}), which can be derived from the trigonal CaAl{sub 2}Si{sub 2}-type structure of the isoelectronic zinc-containing pnictides AZn{sub 2}<span class="hlt">Pn</span>{sub 2} by insertion of additional Ag atoms into trigonal planar sites within [M{sub 2}<span class="hlt">Pn</span>{sub 2}]{sup 2-} slabs built up of edge-sharing tetrahedra. Band structure calculations on SrAg{sub 4}As{sub 2} and SrAg{sub 4}Sb{sub 2} revealed that these charge-balanced Zintl phases actually exhibit no gap at the Fermi level and are predicted to be semimetals. - Graphical abstract: SrAg{sub 4}As{sub 2} and related pnictides adopt a CaCu{sub 4}P{sub 2}-type structure in which additional Ag atoms enter trigonal planar sites within slabs built from edge-sharing tetrahedra. Highlights: Black-Right-Pointing-Pointer AAg{sub 4}<span class="hlt">Pn</span>{sub 2} are the first Ag-containing members of the CaCu{sub 4}P{sub 2}-type structure. Black-Right-Pointing-Pointer Ag atoms are stuffed in trigonal planar sites within CaAl{sub 2}Si{sub 2}-type slabs. Black-Right-Pointing-Pointer Ag-Ag bonding develops through attractive d{sup 10}-d{sup 10} interactions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ApPhL.101r3901D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ApPhL.101r3901D"><span id="translatedtitle">High performance radial <span class="hlt">p-n</span> junction solar cell based on silicon nanopillar array with enhanced decoupling mechanism</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dou, Bingfei; Jia, Rui; Li, Haofeng; Chen, Chen; Ding, Wuchang; Meng, Yanlong; Xing, Zhao; Liu, Xinyu; Ye, Tianchun</p> <p>2012-10-01</p> <p>High performance radial <span class="hlt">p-n</span> junction solar cells based on silicon nanopillar array were synthesized from p-type silicon substrates and compared with planar cell. These radial <span class="hlt">p-n</span> junction cells exhibited considerable higher short-circuit current, due to their unique carriers' decoupling mechanism. After the electrode enhancement via light induced plating, a best efficiency of near 12% was achieved for radial <span class="hlt">p-n</span> junction solar cell, which is better than the planar control cell.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AIPC.1665e0076S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AIPC.1665e0076S"><span id="translatedtitle">Non ideal behavior of AZO/ZnO/ZnPc/Au hybrid <span class="hlt">p-n</span> junction diode</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Singh, Budhi; Ghosh, Subhasis</p> <p>2015-06-01</p> <p>Temperature dependence current density-voltage characteristic of AZO/ZnO/ZnPc/Au inorganic/organic hybrid <span class="hlt">p-n</span> junction diode have been used to investigate the non ideal behavior of AZO/ZnO/ZnPc/Au hybrid <span class="hlt">p-n</span> junction diode. The diode shows high ideality factor of 3.0 at 300 K which increases with decreasing temperature and cannot be explained by the standard Shockley theory of the <span class="hlt">p-n</span> junction diode.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006ApPhL..89w2108S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006ApPhL..89w2108S"><span id="translatedtitle">Liquid-state semiconductor <span class="hlt">p-n</span> junction at 903 K</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sasaki, Yasushi; Hirano, Yoshihiko; Iguchi, Manabu; Ishii, Kuniyoshi</p> <p>2006-12-01</p> <p>A liquid-state semiconductor <span class="hlt">p-n</span> junction has been fabricated by applying the liquid phase separation of the monotectic Sb-Sb2S3 system at 903K. Electrical conduction types of liquid semiconductor of Sb-S alloy and S2S3-x consisting of the immiscible system are found to be p and n types, respectively, from measured absolute Seebeck coefficients. The <span class="hlt">p-n</span> junction was formed by the liquid Sb--S alloy and Sb2S3-x; this is confirmed from the asymmetric current-voltage characteristics or its behavior is rectified. The formation of the liquid-state <span class="hlt">p-n</span> junction in liquid semiconductors has great prospects in the next-generation direct thermal-to-electrical energy conversion materials.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22492823','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22492823"><span id="translatedtitle">Veselago lensing in graphene with a <span class="hlt">p-n</span> junction: Classical versus quantum effects</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Milovanović, S. P. Moldovan, D. Peeters, F. M.</p> <p>2015-10-21</p> <p>The feasibility of Veselago lensing in graphene with a <span class="hlt">p-n</span> junction is investigated numerically for realistic injection leads. Two different set-ups with two narrow leads are considered with absorbing or reflecting side edges. This allows us to separately determine the influence of scattering on electron focusing for the edges and the <span class="hlt">p-n</span> interface. Both semiclassical and tight-binding simulations show a distinctive peak in the transmission probability that is attributed to the Veselago lensing effect. We investigate the robustness of this peak on the width of the injector, the position of the <span class="hlt">p-n</span> interface, and different gate potential profiles. Furthermore, the influence of scattering by both short- and long-range impurities is considered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4759585','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4759585"><span id="translatedtitle">Nanoscale imaging of the photoresponse in <span class="hlt">PN</span> junctions of InGaAs infrared detector</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Xia, Hui; Li, Tian-Xin; Tang, Heng-Jing; Zhu, Liang; Li, Xue; Gong, Hai-Mei; Lu, Wei</p> <p>2016-01-01</p> <p>Electronic layout, such as distributions of charge carriers and electric field, in <span class="hlt">PN</span> junction is determinant for the photovoltaic devices to realize their functionality. Considerable efforts have been dedicated to the carrier profiling of this specific region with Scanning Probe Microscope, yet reliable analysis was impeded by the difficulty in resolving carriers with high mobility and the unclear surface effect, particularly on compound semiconductors. Here we realize nanometer Scanning Capacitance Microscopic study on the cross-section of InGaAs/InP photodetctors with the featured dC/dV layout of <span class="hlt">PN</span> junction unveiled for the first time. It enables us to probe the photo-excited minority carriers in junction region and diagnose the performance deficiency of the diode devices. This work provides an illuminating insight into the <span class="hlt">PN</span> junction for assessing its basic capability of harvesting photo-carriers as well as blocking leakage current in nanoscopic scale. PMID:26892069</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27171402','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27171402"><span id="translatedtitle">Epitaxial Growth of an Organic <span class="hlt">p-n</span> Heterojunction: C60 on Single-Crystal Pentacene.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nakayama, Yasuo; Mizuno, Yuta; Hosokai, Takuya; Koganezawa, Tomoyuki; Tsuruta, Ryohei; Hinderhofer, Alexander; Gerlach, Alexander; Broch, Katharina; Belova, Valentina; Frank, Heiko; Yamamoto, Masayuki; Niederhausen, Jens; Glowatzki, Hendrik; Rabe, Jürgen P; Koch, Norbert; Ishii, Hisao; Schreiber, Frank; Ueno, Nobuo</p> <p>2016-06-01</p> <p>Designing molecular <span class="hlt">p-n</span> heterojunction structures, i.e., electron donor-acceptor contacts, is one of the central challenges for further development of organic electronic devices. In the present study, a well-defined <span class="hlt">p-n</span> heterojunction of two representative molecular semiconductors, pentacene and C60, formed on the single-crystal surface of pentacene is precisely investigated in terms of its growth behavior and crystallographic structure. C60 assembles into a (111)-oriented face-centered-cubic crystal structure with a specific epitaxial orientation on the (001) surface of the pentacene single crystal. The present experimental findings provide molecular scale insights into the formation mechanisms of the organic <span class="hlt">p-n</span> heterojunction through an accurate structural analysis of the single-crystalline molecular contact. PMID:27171402</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27419583','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27419583"><span id="translatedtitle">Inhibiting Klein Tunneling in a Graphene <span class="hlt">p-n</span> Junction without an External Magnetic Field.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Oh, Hyungju; Coh, Sinisa; Son, Young-Woo; Cohen, Marvin L</p> <p>2016-07-01</p> <p>We study by first-principles calculations a densely packed island of organic molecules (F_{4}TCNQ) adsorbed on graphene. We find that with electron doping the island naturally forms a <span class="hlt">p-n</span> junction in the graphene sheet. For example, a doping level of ∼3×10^{13}  electrons per cm^{2} results in a <span class="hlt">p-n</span> junction with an 800 meV electrostatic potential barrier. Unlike in a conventional <span class="hlt">p-n</span> junction in graphene, in the case of the junction formed by an adsorbed organic molecular island we expect that the Klein tunneling is inhibited, even without an applied external magnetic field. Here Klein tunneling is inhibited by the ferromagnetic order that spontaneously occurs in the molecular island upon doping. We estimate that the magnetic barrier in the graphene sheet is around 10 mT. PMID:27419583</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26943894','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26943894"><span id="translatedtitle">Creating Reversible <span class="hlt">p-n</span> Junction on Graphene through Ferritin Adsorption.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mulyana, Yana; Uenuma, Mutsunori; Okamoto, Naofumi; Ishikawa, Yasuaki; Yamashita, Ichiro; Uraoka, Yukiharu</p> <p>2016-03-01</p> <p>An alternative way to construct a stable <span class="hlt">p-n</span> junction on graphene-based field effect transistor (G-FET) through physical adsorption of ferritin (spherical protein shell) is presented. The produced <span class="hlt">p-n</span> junction on G-FET could also operate through water-gate. Native ferritins are known to be negatively charged in wet condition; however, we found that native negatively charged ferritins became positively charged after performing electron beam (EB)-irradiation. We utilized this property to construct <span class="hlt">p-n</span> junction on G-FET. We found also that EB-irradiation could remove the effect of charged impurity adsorbed on graphene layer, thus the Dirac point was adjusted to gate voltage Vg = 0. PMID:26943894</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19960047115','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19960047115"><span id="translatedtitle">Fast Risetime Reverse Bias Pulse Failures in SiC <span class="hlt">PN</span> Junction Diodes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Neudeck, Philip G.; Fazi, Christian; Parsons, James D.</p> <p>1996-01-01</p> <p>SiC-based high temperature power devices are being developed for aerospace systems which will require high reliability. One behavior crucial to power device reliability. To date, it has necessarily been assumed to date is that the breakdown behavior of SiC <span class="hlt">pn</span> junctions will be similar to highly reliable silicon-based <span class="hlt">pn</span> junctions. Challenging this assumption, we report the observation of anomalous unreliable reverse breakdown behavior in moderately doped (2-3 x 10(exp 17) cm(exp -3)) small-area 4H- and 6H-SiC <span class="hlt">pn</span> junction diodes at temperatures ranging from 298 K (25 C) to 873 K (600 C). We propose a mechanism in which carrier emission from un-ionized dopants and deep level defects leads to this unstable behavior. The fundamental instability mechanism is applicable to all wide bandgap semiconductors whose dopants are significantly un-ionized at typical device operating temperatures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MARL30013W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MARL30013W"><span id="translatedtitle">A model of dopant diffusion through a strongly correlated <span class="hlt">p-n</span> junction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wieteska, Jedrzej; Brierley, Richard; Guzman-Verri, Gian; Moller, Gunnar; Littlewood, Peter; Littlewood group Collaboration</p> <p></p> <p>The diffusion of charged ions in a solid depends on an equation of state that balances diffusive and screened electrostatic forces, and is well understood in the case of conventional semiconductors and metals. In the case of a strongly-correlated material, the physics is different, and expected to be relevant, for example, in Li-ion battery cathodes. We propose a model of dopant ion motion through a strongly correlated <span class="hlt">p-n</span> junction. Our approach is to consider diffusive (Nernst-Planck) dynamics of dopants under screened electrostatic interactions computed within a mean-field (Thomas-Fermi) approximation. Dopant profiles as function of time are calculated for a <span class="hlt">p-n</span> junction held at constant voltage. In the case where filling levels are near a correlation-induced gap, Mott insulating regions can form at the <span class="hlt">p-n</span> interface and their dynamics is studied.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ApPhL.100p3115M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ApPhL.100p3115M"><span id="translatedtitle">Unipolar transport in bilayer graphene controlled by multiple <span class="hlt">p-n</span> interfaces</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Miyazaki, Hisao; Li, Song-Lin; Nakaharai, Shu; Tsukagoshi, Kazuhito</p> <p>2012-04-01</p> <p>Unipolar transport is demonstrated in a bilayer graphene with a series of <span class="hlt">p-n</span> junctions and is controlled by electrostatic biasing by a comb-shaped top gate. The OFF state is induced by multiple barriers in the <span class="hlt">p-n</span> junctions, where the band gap is generated by applying a perpendicular electric field to the bilayer graphene, and the ON state is induced by the p-p or n-n configurations of the junctions. As the number of the junction increases, current suppression in the OFF state is pronounced. The multiple <span class="hlt">p-n</span> junctions also realize the saturation of the drain current under relatively high source-drain voltages.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19740048024&hterms=ferrari&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dferrari','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19740048024&hterms=ferrari&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dferrari"><span id="translatedtitle">The effects of notch filters on the correlation properties of a <span class="hlt">PN</span> signal</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sussman, S. M.; Ferrari, E. J.</p> <p>1974-01-01</p> <p>With wideband pseudo-noise (<span class="hlt">PN</span>) communications systems, it is sometimes desirable to supplement the inherent interference rejection capabilities by adding notch filters to attenuate relatively narrowband interference. This correspondence presents an investigation of the effects of notch filters on the performance of <span class="hlt">PN</span> correlation receivers. A theoretical analysis of the correlation drop due to filter distortion has been conducted and confirmed by experimentation. Additional measurements and analysis have established the trade-off between correlation drop and interference suppression as a function of interference bandwidth. A typical result is that by incurring a penalty of a 1-dB drop in correlation peak, interfering signals having bandwidths of 2 to 3% of the <span class="hlt">PN</span> chip rate can be attenuated by 25 dB.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...621544X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...621544X"><span id="translatedtitle">Nanoscale imaging of the photoresponse in <span class="hlt">PN</span> junctions of InGaAs infrared detector</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xia, Hui; Li, Tian-Xin; Tang, Heng-Jing; Zhu, Liang; Li, Xue; Gong, Hai-Mei; Lu, Wei</p> <p>2016-02-01</p> <p>Electronic layout, such as distributions of charge carriers and electric field, in <span class="hlt">PN</span> junction is determinant for the photovoltaic devices to realize their functionality. Considerable efforts have been dedicated to the carrier profiling of this specific region with Scanning Probe Microscope, yet reliable analysis was impeded by the difficulty in resolving carriers with high mobility and the unclear surface effect, particularly on compound semiconductors. Here we realize nanometer Scanning Capacitance Microscopic study on the cross-section of InGaAs/InP photodetctors with the featured dC/dV layout of <span class="hlt">PN</span> junction unveiled for the first time. It enables us to probe the photo-excited minority carriers in junction region and diagnose the performance deficiency of the diode devices. This work provides an illuminating insight into the <span class="hlt">PN</span> junction for assessing its basic capability of harvesting photo-carriers as well as blocking leakage current in nanoscopic scale.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016NIMPB.372...67L&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016NIMPB.372...67L&link_type=ABSTRACT"><span id="translatedtitle">Two-dimensional dopant profiling of gallium nitride <span class="hlt">p-n</span> junctions by scanning capacitance microscopy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lamhamdi, M.; Cayrel, F.; Frayssinet, E.; Bazin, A. E.; Yvon, A.; Collard, E.; Cordier, Y.; Alquier, D.</p> <p>2016-04-01</p> <p>Two-dimensional imaging of dopant profiles for n and p-type regions are relevant for the development of new power semiconductors, especially for gallium nitride (GaN) for which classical profiling techniques are not adapted. This is a challenging task since it needs a technique with simultaneously good sensitivity, high spatial resolution and high dopant gradient resolution. To face these challenges, scanning capacitance microscopy combined with Atomic Force Microscopy is a good candidate, presenting reproducible results, as demonstrated in literature. In this work, we attempt to distinguish reliably and qualitatively the various doping concentrations and type at <span class="hlt">p-n</span> and unipolar junctions. For both <span class="hlt">p-n</span> and unipolar junctions three kinds of samples were prepared and measured separately. The space-charge region of the <span class="hlt">p-n</span> metallurgical junction, giving rise to different contrasts under SCM imaging, is clearly observed, enlightening the interest of the SCM technique.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006ApPhL..89s2116L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006ApPhL..89s2116L"><span id="translatedtitle">Band anticrossing in InGa<span class="hlt">PN</span> alloys induced by N-related localized states</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lin, K. I.; Hwang, J. S.</p> <p>2006-11-01</p> <p>Temperature-dependent photoreflectance measurements are employed to characterize the electronic band structure of InGa<span class="hlt">PN</span> grown on GaAs substrates. In addition to the fundamental band gap, the upper subband E+ is observed as predicted by the band anticrossing (BAC) model. By eliminating the contributions of the epitaxial-strain and atomic-ordering effects in InGa<span class="hlt">PN</span> and also assigning the localized state energy EN introduced by an isolated N to be 2.040eV at 293K, the interaction potential V is determined as 1.449±0.170eV. The incorporation of a temperature-dependent EN level into the BAC model fits the experimental data better than assuming EN to be a constant. This contrasts with previously published results and so provides a different view of the temperature dependence of the EN level in InGa<span class="hlt">PN</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1107824','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1107824"><span id="translatedtitle">Security of Classic <span class="hlt">PN</span>-Spreading Codes for Hybrid DS/FH Spread-Spectrum Systems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ma, Xiao; Olama, Mohammed M; Kuruganti, Phani Teja; Smith, Stephen Fulton; Djouadi, Seddik M</p> <p>2013-01-01</p> <p>Hybrid direct sequence/frequency hopping (DS/FH) spread-spectrum communication systems have recently received considerable interest in commercial applications in addition to their use in military communications because they accommodate high data rates with high link integrity, even in the presence of significant multipath effects and interfering signals. The security of hybrid DS/FH systems strongly depends on the choice of <span class="hlt">PN</span>-spreading code employed. In this paper, we examine the security, in terms of unicity distance, of linear maximal-length, Gold, and Kasami <span class="hlt">PN</span>-spreading codes for DS, FH, and hybrid DS/FH spread-spectrum systems without additional encryption methods. The unicity distance is a measure of the minimum amount of ciphertext required by an eavesdropper to uniquely determine the specific key used in a cryptosystem and hence break the cipher. Numerical results are presented to compare the security of the considered <span class="hlt">PN</span>-spreading codes under known-ciphertext attacks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26892069','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26892069"><span id="translatedtitle">Nanoscale imaging of the photoresponse in <span class="hlt">PN</span> junctions of InGaAs infrared detector.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Xia, Hui; Li, Tian-Xin; Tang, Heng-Jing; Zhu, Liang; Li, Xue; Gong, Hai-Mei; Lu, Wei</p> <p>2016-01-01</p> <p>Electronic layout, such as distributions of charge carriers and electric field, in <span class="hlt">PN</span> junction is determinant for the photovoltaic devices to realize their functionality. Considerable efforts have been dedicated to the carrier profiling of this specific region with Scanning Probe Microscope, yet reliable analysis was impeded by the difficulty in resolving carriers with high mobility and the unclear surface effect, particularly on compound semiconductors. Here we realize nanometer Scanning Capacitance Microscopic study on the cross-section of InGaAs/InP photodetectors with the featured dC/dV layout of <span class="hlt">PN</span> junction unveiled for the first time. It enables us to probe the photo-excited minority carriers in junction region and diagnose the performance deficiency of the diode devices. This work provides an illuminating insight into the <span class="hlt">PN</span> junction for assessing its basic capability of harvesting photo-carriers as well as blocking leakage current in nanoscopic scale. PMID:26892069</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AIPA....5d7104Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AIPA....5d7104Y"><span id="translatedtitle">The ZnO <span class="hlt">p-n</span> homojunctions modulated by ZnMgO barriers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Jing-Jing; Fang, Qing-Qing; Wang, Dan-Dan; Du, Wen-Han</p> <p>2015-04-01</p> <p>In this paper, we fabricated the ultrathin ZnO <span class="hlt">p-n</span> homojunctions, which modulated by ZnMgO asymmetrical double barriers (ADB). The ADB <span class="hlt">p-n</span> homojunctions displays step-like curve in the absorption spectrums, this is the first time that quantum confinement effect has been observed in the absorption spectrums at room temperature (RT). The Hall-effect data confirm there is 2-dimensional electron gas in the interface of the ZnMgO ADB <span class="hlt">p-n</span> junctions. The quantum confinement effect enhances the hall-mobility μ to 103 cm2V -1s-1 based on the polarity of the films. There was no rectification property in the ZnO homojunctions with thickness of 250nm, however, when the ADB was added in the n-type layer of the homojunctions, it displays a typical Zener diode rectification property in the I-V curve.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhCS.709a2006I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhCS.709a2006I"><span id="translatedtitle">Porous silicon Bragg reflectors on multi-crystalline silicon wafer with <span class="hlt">p-n</span> junction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ivanov, I. I.; Skryshevsky, V. A.; Kyslovets, O. S.; Nychyporuk, T.; Lemiti, M.</p> <p>2016-04-01</p> <p>Bragg reflectors consisting of the sequence of dielectric layers are considered to create <span class="hlt">p-n</span> junction solar cells (SC) with improved efficiency in the longwave spectral range. Bragg mirrors (BM) based on porous silicon (PS) mutilayers at the backside of single crystalline and multicrystalline silicon wafer were formed by electrochemically etching. Maximal experimental reflectivity for BM on multicrystalline substrate achieves 62% due to the natural crystallites disorientation of multicrystalline substrate, whereas for single crystalline silicon the reflectivity in maximum is 87%. BM was formed also on rear side of multicrystalline silicon wafer with <span class="hlt">p-n</span> junction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APExp...9e5201N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APExp...9e5201N"><span id="translatedtitle">Multilayer ReS2 lateral <span class="hlt">p-n</span> homojunction for photoemission and photodetection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Najmzadeh, Mohammad; Ko, Changhyun; Wu, Kedi; Tongay, Sefaattin; Wu, Junqiao</p> <p>2016-05-01</p> <p>In this paper, a multilayer ReS2 <span class="hlt">p-n</span> homojunction is fabricated on an oxidized Si substrate, and its photoemission under a forward bias and its photodetection under a reverse bias are reported for the first time. Au nanoparticles were used to make lateral <span class="hlt">p-n</span> homojunctions. The device shows room temperature photoemission in the IR range, and in the photodetector mode, it shows a 0.41 A/W responsivity under illumination by a 660 nm red laser.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1164345','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1164345"><span id="translatedtitle">Semiconductor device <span class="hlt">PN</span> junction fabrication using optical processing of amorphous semiconductor material</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sopori, Bhushan; Rangappan, Anikara</p> <p>2014-11-25</p> <p>Systems and methods for semiconductor device <span class="hlt">PN</span> junction fabrication are provided. In one embodiment, a method for fabricating an electrical device having a <span class="hlt">P-N</span> junction comprises: depositing a layer of amorphous semiconductor material onto a crystalline semiconductor base, wherein the crystalline semiconductor base comprises a crystalline phase of a same semiconductor as the amorphous layer; and growing the layer of amorphous semiconductor material into a layer of crystalline semiconductor material that is epitaxially matched to the lattice structure of the crystalline semiconductor base by applying an optical energy that penetrates at least the amorphous semiconductor material.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6382654','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/6382654"><span id="translatedtitle">Spectral sensitization in an organic <span class="hlt">p-n</span> junction photovoltaic cell</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Harima, Y.; Yamashita, K.; Suzuki, H.</p> <p>1984-11-15</p> <p>Electric and photovoltaic characteristics of an orgainic <span class="hlt">p-n</span> junction photovoltaic cell are described, where the p-type and n-type compounds used are phthalocyaninatozinc (II) (ZnPc) and 5, 10, 15, 20 -tetra (3-pyridyl) porphyrin (TPyP), respectively. The <span class="hlt">p-n</span> junction cell with a thin film of TPyP exhibited stronger spectral sensitization and better spectral match to a solar spectrum than the Schottky barrier cells using either TPyP and ZnPc. The energy conversion efficiency found was about 2% for monochromatic light at 430 nm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012SPIE.8256E..1OM','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012SPIE.8256E..1OM"><span id="translatedtitle">Full device analysis of novel metamaterial coated <span class="hlt">PN</span> and MIS solar cells using numerical methods</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mandel, Isroel; Gollub, Jonah N.; Sarantos, Chris; Pishbin, Nafiseh; Crouse, David T.</p> <p>2012-02-01</p> <p>In this work we describe how to model the efficiency of solar cells with novel metamaterial coatings optimized for light harvesting. Full device modeling is implemented using optical and electrical simulations. As a proof of concept, we simulate the operation of a metamaterial contact on a first generation monocrystalline silicon solar cell. We compare device characteristics and efficiencies to standard antireflective coatings applied to a grid contact cell. The effects of the metamaterial contact on silicon solar cell efficiencies is discussed for <span class="hlt">PN</span> junction and metal-insulator-semiconductor cell structures. It is found that the metal-insulator-semiconductor solar cell designed performs better than the <span class="hlt">PN</span> junction cell.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002Tectp.358...39R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002Tectp.358...39R"><span id="translatedtitle"><span class="hlt">Pn</span> and Sn tomography across Eurasia to improve regional seismic event locations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ritzwoller, Michael H.; Barmin, Mikhail P.; Villaseñor, Antonio; Levshin, Anatoli L.; Engdahl, E. Robert</p> <p>2002-11-01</p> <p>This paper has three motivations: first, to map <span class="hlt">Pn</span> and Sn velocities beneath most of Eurasia to reveal information on a length scale relevant to regional tectonics, second, to test recently constructed 3-D mantle models and, third, to develop and test a method to produce <span class="hlt">Pn</span> and Sn travel time correction surfaces which are the 3-D analogue of travel time curves for a 1-D model. Our third motive is inspired by the need to improve regional location capabilities in monitoring nuclear treaties such as the nuclear Comprehensive Test Ban Treaty (CTBT). To a groomed version of the ISC/NEIC data, we apply the tomographic method of Barmin et al. [Pure Appl. Geophys. (2001)], augmented to include station and event corrections and an epicentral distance correction. The <span class="hlt">Pn</span> and Sn maps are estimated on a 1°×1° grid throughout Eurasia. We define the phases <span class="hlt">Pn</span> and Sn as arriving between epicentral distances of 3° and 15°. After selection, the resulting data set consists of about 1,250,000 <span class="hlt">Pn</span> and 420,000 Sn travel times distributed inhomogeneously across Eurasia. The rms misfit to the entire Eurasian data set from the <span class="hlt">Pn</span> and Sn model increases nearly linearly with distance and averages about 1.6 s for <span class="hlt">Pn</span> and 3.2 s for Sn, but is better for events that occurred on several nuclear test sites and for selected high-quality data subsets. The <span class="hlt">Pn</span> and Sn maps compare favorably with recent 3-D models of P and S in the uppermost mantle and with recently compiled teleseismic station corrections across the region. The most intriguing features on the maps are the low-velocity anomalies that characterize most tectonically deformed regions such as the anomaly across central and southern Asia and the Middle East that extends along a tortuous path from Turkey in the west to Lake Baikal in the east. These anomalies are related to the closing of the Neo-Tethys Ocean and the collision of India with Asia. The uppermost mantle beneath the Pacific Rim back-arc is also very slow, presumably due to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016EPJWC.11706024G&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016EPJWC.11706024G&link_type=ABSTRACT"><span id="translatedtitle">Transfer to the continuum calculations of quasifree (p,<span class="hlt">pn</span>) and (p,2p) reactions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gomez-Ramos, M.; Moro, A. M.</p> <p>2016-05-01</p> <p>Nucleon removal (p, <span class="hlt">pn</span>) and (p, 2p) reactions at intermediate energies have gained renewed attention in recent years as a tool to extract information from exotic nuclei. The information obtained from these experiments is expected to be sensitive to deeper portions of the wave function of the removed nucleon than knockout reactions with heavier targets. In this contribution, we present calculations for (p, 2p) and (p, <span class="hlt">pn</span>) reactions performed within the so-called transfer to the continuum method (TR*). Results for stable and unstable nuclei are presented, and compared with experimental data, when available.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22262570','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22262570"><span id="translatedtitle">Visualizing the photovoltaic behavior of a type-II <span class="hlt">p-n</span> heterojunction superstructure</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Xing, Juanjuan; Takeguchi, Masaki; Hashimoto, Ayako; Cao, Junyu; Ye, Jinhua</p> <p>2014-04-21</p> <p>Photovoltaic behavior of a CaFe{sub 2}O{sub 4}/ZnFe{sub 2}O{sub 4} <span class="hlt">p-n</span> multi-junction was investigated with electron holography combined with an in situ light irradiation system. Potential profiles of the samples with and without light irradiation were extracted to measure the open circuit photovoltage generated either by the whole heterojunction superstructure or from each <span class="hlt">p-n</span> junction. Investigation on the variation in the energy band configuration under light irradiation revealed the mechanism involved in the photoelectric effect, with respect to the properties of the heterojunction and its periodic quantum structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22253860','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22253860"><span id="translatedtitle">Dopant-induced random telegraph signal in nanoscale lateral silicon <span class="hlt">pn</span> diodes at low temperatures</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Purwiyanti, Sri; Department of Electrical Engineering, University of Indonesia, Depok, 16424 Jakarta ; Nowak, Roland; Division of Sensors and Measuring Systems, Warsaw University of Technology, Sw. A. Boboli 8, 02-525 Warsaw ; Moraru, Daniel; Mizuno, Takeshi; Tabe, Michiharu; Hartanto, Djoko; Jablonski, Ryszard</p> <p>2013-12-09</p> <p>We studied current-voltage characteristics of nanoscale <span class="hlt">pn</span> diodes having the junction formed in a laterally patterned ultrathin silicon-on-insulator layer. At temperatures below 30 K, we observed random telegraph signal (RTS) in a range of forward bias. Since RTS is observed only for <span class="hlt">pn</span> diodes, but not for pin diodes, one dopant among phosphorus donors or boron acceptors facing across the junction is likely responsible for potential changes affecting the current. Based also on potential measurements by low-temperature Kelvin probe force microscope, RTS is ascribed to trapping/detrapping of carriers by/from a single dopant near the farther edge of the depletion region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002EGSGA..27.1215N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002EGSGA..27.1215N"><span id="translatedtitle">Teleseismic <span class="hlt">Pn</span> Coda Explained By Crustal Scattering - Modelling of Russian Pne Data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nielsen, L.; Thybo, H.; Morozov, I. B.; Smithson, S. B.; Solodilov, L.</p> <p></p> <p>Teleseismic (or long-range) <span class="hlt">Pn</span> phases, which carry a high-amplitude, incoherent coda of several seconds duration, are observed to offsets of more than 3000 km along the Peaceful Nuclear Explosion seismic profiles Quartz and Ruby located in the former Soviet Union. We interpret these arrivals as multiple sub-Moho refractions which travel over large distances due to a positive upper mantle velocity gradient. The coda of the teleseismic <span class="hlt">Pn</span> arrivals is explained by scattering caused by lower crustal small-scale heterogeneity. This scattering is modelled by reflectivity calculations for one-dimensional (1-D) models and by computationally expensive visco-elastic finite- difference calculations for 2-D heterogeneous models. The 1-D models fit observa- tions, except for the obvious fact that the layered medium gives rise to a too coherent coda of slightly too low amplitude for realistic lower crustal velocity contrasts. The 2- D models match both the amplitude and the incoherent appearance of the teleseismic <span class="hlt">Pn</span> coda. The choice of vertical upper mantle velocity gradient is found to be a critical factor for the propagation of the teleseismic <span class="hlt">Pn</span>. We base our conclusions on mod- els which contain a steep vertical upper mantle velocity gradient, in agreement with results from travel time modelling performed along profile Quartz. This includes a higher vertical gradient than in e.g. the IASPEI91 model, which has been assumed by other authors. Models with a high vertical gradient match the key features of the tele- seismic <span class="hlt">Pn</span> arrivals. If a significantly lower gradient is chosen then the models cannot reproduce the kinematics and the coda characteristics of the teleseismic <span class="hlt">Pn</span>. Our mod- els are in good agreement with deep seismic wide-angle and normal-incidence data from other areas which typically show a reflective lower crust and an almost trans- parent uppermost mantle. The positive upper mantle velocity gradient below profiles Quartz and Ruby forms a waveguide which gives</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19820043175&hterms=search+algorithm&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dsearch%2Balgorithm','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19820043175&hterms=search+algorithm&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dsearch%2Balgorithm"><span id="translatedtitle">Performance analysis for the expanding search <span class="hlt">PN</span> acquisition algorithm. [pseudonoise in spread spectrum transmission</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Braun, W. R.</p> <p>1982-01-01</p> <p>An approach is described for approximating the cumulative probability distribution of the acquisition time of the serial pseudonoise (<span class="hlt">PN</span>) search algorithm. The results are applicable to both variable and fixed dwell time systems. The theory is developed for the case where some a priori information is available on the <span class="hlt">PN</span> code epoch (reacquisition problem or acquisition of very long codes). Also considered is the special case of a search over the whole code. The accuracy of the approximation is demonstrated by comparisons with published exact results for the fixed dwell time algorithm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014ApPhL.104p3105X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014ApPhL.104p3105X"><span id="translatedtitle">Visualizing the photovoltaic behavior of a type-II <span class="hlt">p-n</span> heterojunction superstructure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xing, Juanjuan; Takeguchi, Masaki; Hashimoto, Ayako; Cao, Junyu; Ye, Jinhua</p> <p>2014-04-01</p> <p>Photovoltaic behavior of a CaFe2O4/ZnFe2O4 <span class="hlt">p-n</span> multi-junction was investigated with electron holography combined with an in situ light irradiation system. Potential profiles of the samples with and without light irradiation were extracted to measure the open circuit photovoltage generated either by the whole heterojunction superstructure or from each <span class="hlt">p-n</span> junction. Investigation on the variation in the energy band configuration under light irradiation revealed the mechanism involved in the photoelectric effect, with respect to the properties of the heterojunction and its periodic quantum structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25241963','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25241963"><span id="translatedtitle">The structural classification of the highly disordered crystal phases of [Nn][BF4], [Nn][PF6], [<span class="hlt">Pn</span>][BF4], and [<span class="hlt">Pn</span>][PF6] salts (Nn(+) = tetraalkylammonium and <span class="hlt">Pn</span>(+) = tetraalkylphosphonium).</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Matsumoto, Kazuhiko; Harinaga, Ukyo; Tanaka, Ryo; Koyama, Akira; Hagiwara, Rika; Tsunashima, Katsuhiko</p> <p>2014-11-21</p> <p>The structures of 16 symmetric tetraalkylammonium (Nn(+)) and tetraalkylphosphonium (<span class="hlt">Pn</span>(+)) salts ([Nn][BF4], [Nn][PF6], [<span class="hlt">Pn</span>][BF4], and [<span class="hlt">Pn</span>][PF6], where n = 1 to 4, and denotes the number of carbon atoms in each alkyl chain) have been investigated by X-ray diffraction in order to elucidate the effect of ion size on the disordered structure of organic salts. All the salts exhibit one or more solid-solid phase transitions in differential scanning calorimetric curves. Powder X-ray diffraction revealed that the highest temperature solid phase of these salts belongs to a crystal system with a high cubic or hexagonal symmetry. The structures are classified into 5 different types: CsCl', NaCl, NaCl', inverse NiAs, and TBPPF6. The CsCl'-type whose octant corresponds to the original CsCl unit cell is observed for [N1][PF6] owing to the orientational difference for the cation or the anion. The NaCl-type structure is observed for the N2(+) and P2(+) salts while the NaCl'-type structure is observed for [N3][PF6], where the configuration of ions is based on the NaCl-type but the four equivalent positions in the original NaCl lattice split into two sets of equivalent positions (three and one). The inverse NiAs structure is observed for [P3][PF6]. Single-crystal X-ray diffraction reveals that the disordering of ions in [P4][PF6] becomes more significant with increasing temperature. The new structure of a cubic phase, the TBPPF6-type structure, is found for the salts with long alkyl chains. The structure is roughly determined at 333 K and the ions therein are highly disordered but not rotating. The validity of the radius ratio rule is confirmed through appropriate assessment of the ion size. PMID:25241963</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/273397','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/273397"><span id="translatedtitle">A critical test of organic <span class="hlt">P-N</span> photovoltaic cells</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bird, G.R.</p> <p>1996-09-01</p> <p>We present an urgent view of the field of organic solid state photovoltaic cells. This is a proper time to select the most promising materials from the Electrophotographic Industry, materials long tried in terms of stability, high quantum <span class="hlt">yield</span> of charge carriers, but set apart by unusually high quantum <span class="hlt">yields</span> at low applied fields. Our experience with the candidate dyes has covered new tests for identifiable impurities and removal of these impurities by verifiable methods. A new method of purification, reactive train sublimation, has been developed for DNT, one of the simplest of the outstanding perylene dyes, and the method seems applicable to some of the other promising perylene derivatives. It removes the offending impurity by converting it into the desired pure product. The role of water of hydration in the {open_quotes}wine cellar effect{close_quotes}, the slowly rising performance of newly made phthalocyanine containing cells has been analyzed. Under the concept of feasibility testing before a final refinement for practicality of materials and production methods, the hydration can be controlled for high level testing. At the same time, efforts go forward to eliminate the need. At least one of the best phthalocyanine components, X-H{sub 2}Pc, does not require water for peak performance. Finally, we have attacked BBIP (bis-benzimidazole perylene) one of the best and most enigmatic of the near infrared sensors. It has long been known and used as a mixture of synthetic isomers, and we hypothesize that either of these would be better than the uncontrolled mixture. A partial success in the form of isolating highly enriched crystals for an X-ray structure of the trans-molecule, is first presented here. A simple optical analysis method has been developed to follow enrichment procedures. For all of its difficult history, this material seems closest to a state of readiness for critical feasibility testing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Nanos...7.7267W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Nanos...7.7267W"><span id="translatedtitle">The effects of shell layer morphology and processing on the electrical and photovoltaic properties of silicon nanowire radial <span class="hlt">p+-n</span>+ junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Xin; Ke, Yue; Kendrick, Chito E.; Weng, Xiaojun; Shen, Haoting; Kuo, Mengwei; Mayer, Theresa S.; Redwing, Joan M.</p> <p>2015-04-01</p> <p>Single wire <span class="hlt">p+-n</span>+ radial junction nanowire solar cell devices were fabricated by low pressure chemical vapor deposition of n+ silicon shell layers on p+ silicon nanowires synthesized by vapor-liquid-solid growth. The n+-shell layers were deposited at two growth temperatures (650 °C and 950 °C) to study the impact of shell crystallinity on the device properties. The n-type Si shell layers deposited at 650 °C were polycrystalline and resulted in diodes that were not rectifying. A pre-coating anneal at 950 °C in H2 improved the structural quality of the shell layers and <span class="hlt">yielded</span> diodes with a dark saturation current density of 3 × 10-5 A cm-2. Deposition of the n-type Si shell layer at 950 °C resulted in epitaxial growth on the nanowire core, which lowered the dark saturation current density to 3 × 10-7 A cm-2 and increased the solar energy conversion efficiency. Temperature-dependent current-voltage measurements demonstrated that the 950 °C coated devices were abrupt junction <span class="hlt">p+-n</span>+ diodes with band-to-band tunneling at high reverse-bias voltage, while multi-step tunneling degraded the performance of devices fabricated with a 950 °C anneal and 650 °C coating. The higher trap density of the 950 °C annealed 650 °C coated devices is believed to arise from the polycrystalline nature of the shell layer coating, which results in an increased density of dangling bonds at the <span class="hlt">p+-n</span>+ junction interface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S43A2773H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S43A2773H"><span id="translatedtitle">A frequency-dependent log-quadratic <span class="hlt">Pn</span> spreading model in the Northeast China and Korean peninsula</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hao, J.; Zhao, L.; Xie, X. B.; Yao, Z.</p> <p>2015-12-01</p> <p>In 9 October 2006, 25 May 2009, and 12 February 2013, North Korea conducted three successive nuclear tests near the China-Korea border. Based on 297 broadband stations distributed in East China, South Korea, and Japan, the digital seismograms from these nuclear tests are collected to investigate the geometric spreading and attenuation of seismic <span class="hlt">Pn</span> waves in Northeast China and Korean Peninsula. A highly accurate broadband <span class="hlt">Pn</span>-wave data set generated by North Korean nuclear tests is used to constrain parameters of a frequency-dependent log-quadratic geometric spreading function and a power-law <span class="hlt">Pn</span> Q model. The geometric spreading function and apparent <span class="hlt">Pn</span> wave Q is obtained for the studied area between 2.0 and 10.0 Hz. By taking the two-station amplitude ratios of the <span class="hlt">Pn</span> spectra, followed by correcting it for the known spreading function, we can strip the effects of source and crust legs from the apparent <span class="hlt">Pn</span> Q, and retrieve the P-wave attenuation information along the pure upper mantle path. We then use a tomographic approach to obtain the upper mantle P-wave attenuation in Northeast China and Korean Peninsula. The <span class="hlt">Pn</span> wave spectra observed in China are compared with those recorded in Japan, and the result reveals that the high-frequency <span class="hlt">Pn</span> signal across the oceanic path attenuated faster than those through the continental path. This work was supported by the National Natural Science Foundation of China (grants 41174048 and 41374065).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26272579','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26272579"><span id="translatedtitle">Draft Genome Sequence of Bacillus pseudalcaliphilus <span class="hlt">PN</span>-137T (DSM 8725), an Alkaliphilic Halotolerant Bacterium Isolated from Garden Soils.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Jie-Ping; Liu, Bo; Liu, Guo-Hong; Xiao, Rong-Feng; Zheng, Xue-Fang; Shi, Huai; Ge, Ci-Bin</p> <p>2015-01-01</p> <p>Bacillus pseudalcaliphilus <span class="hlt">PN</span>-137(T) (DSM 8725) is a Gram-positive, spore-forming, alkaliphilic, and halotolerant bacterium. Here, we report the 4.49-Mb genome sequence of B. pseudalcaliphilus <span class="hlt">PN</span>-137(T), which will accelerate the application of this alkaliphile and provide useful information for genomic taxonomy and phylogenomics of Bacillus-like bacteria. PMID:26272579</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25162930','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25162930"><span id="translatedtitle">Crystal growth and characterization of the narrow-band-gap semiconductors OsPn₂ (<span class="hlt">Pn</span> = P, As, Sb).</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bugaris, Daniel E; Malliakas, Christos D; Shoemaker, Daniel P; Do, Dat T; Chung, Duck Young; Mahanti, Subhendra D; Kanatzidis, Mercouri G</p> <p>2014-09-15</p> <p>Using metal fluxes, crystals of the binary osmium dipnictides Os<span class="hlt">Pn</span>2 (<span class="hlt">Pn</span> = P, As, Sb) have been grown for the first time. Single-crystal X-ray diffraction confirms that these compounds crystallize in the marcasite structure type with orthorhombic space group Pnnm. The structure is a three-dimensional framework of corner- and edge-sharing Os<span class="hlt">Pn</span>6 octahedra, as well as [<span class="hlt">Pn</span>2(4-)] anions. Raman spectroscopy shows the presence of P-P single bonds, consistent with the presence of [<span class="hlt">Pn</span>2(-4)] anions and formally Os(4+) cations. Optical-band-gap and high-temperature electrical resistivity measurements indicate that these materials are narrow-band-gap semiconductors. The experimentally determined Seebeck coefficients reveal that nominally undoped OsP2 and OsSb2 are n-type semiconductors, whereas OsAs2 is p-type. Electronic band structure using density functional theory calculations shows that these compounds are indirect narrow-band-gap semiconductors. The bonding p orbitals associated with the <span class="hlt">Pn</span>2 dimer are below the Fermi energy, and the corresponding antibonding states are above, consistent with a <span class="hlt">Pn-Pn</span> single bond. Thermopower calculations using Boltzmann transport theory and constant relaxation time approximation show that these materials are potentially good thermoelectrics, in agreement with experiment. PMID:25162930</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22012080','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22012080"><span id="translatedtitle">Synthesis, physical properties and electronic structure of Sr{sub 1-x}La{sub x}Cu{sub 2}<span class="hlt">Pn</span>{sub 2} (<span class="hlt">Pn</span>=P, As, Sb)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Qin Mingsheng; Yang Chongyin; Wang Yaoming; Yang Zhongtian; Chen Ping; Huang Fuqiang</p> <p>2012-03-15</p> <p>To explore new series of high-T{sub c} superconductors, Cu-based ternary pnictides of SrCu{sub 2}<span class="hlt">Pn</span>{sub 2} (<span class="hlt">Pn</span>=P, As, Sb) with La doping were synthesized at 1073 K from the stoichiometric reaction of the elements. The electrical and magnetic properties as well as the electronic structure were systematically investigated. Absence of superconductive transition was observed over the temperature range from room temperature down to 2 K, and these materials show p-type metal-like conductivity and Pauli paramagnetic behavior. The near E{sub F} bands mainly originate from Cu 3d and <span class="hlt">Pn</span> np states and the value of total densities of states (DOS) becomes higher as <span class="hlt">Pn</span> goes from P to Sb. The results provides us with considerable information for a better understanding of the transport properties in pnictides. - Graphical abstract: Sr{sub 1-x}La{sub x}Cu{sub 2}<span class="hlt">Pn</span>{sub 2} (<span class="hlt">Pn</span>=P, As, Sb) show metal-like conducting behavior and no superconductive transition was observed from 300 K down to 2 K. Highlights: Black-Right-Pointing-Pointer The superconductivity and electronic structure of Sr{sub 1-x}La{sub x}Cu{sub 2}<span class="hlt">Pn</span>{sub 2} were investigated. Black-Right-Pointing-Pointer Sr{sub 1-x}La{sub x}Cu{sub 2}<span class="hlt">Pn</span>{sub 2} show p-type metal-like conducting behavior and paramagnetism. Black-Right-Pointing-Pointer The near E{sub F} electronic structure of SrCu{sub 2}<span class="hlt">Pn</span>{sub 2} mainly originate from Cu 3d and <span class="hlt">Pn</span> np states.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JCoPh.313..549H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JCoPh.313..549H"><span id="translatedtitle">A discretization of the multigroup <span class="hlt">PN</span> radiative transfer equation on general meshes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hermeline, F.</p> <p>2016-05-01</p> <p>We propose and study a finite volume method of discrete duality type for discretizing the multigroup <span class="hlt">PN</span> approximation of radiative transfer equation on general meshes. This method is second order-accurate on a very large variety of meshes, stable under a Courant-Friedrichs-Lewy condition and it preserves naturally the diffusion asymptotic limit.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26866621','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26866621"><span id="translatedtitle">Spatioselective Electrochemical and Photoelectrochemical Functionalization of Silicon Microwires with Axial <span class="hlt">p/n</span> Junctions.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Milbrat, Alexander; Elbersen, Rick; Kas, Recep; Tiggelaar, Roald M; Gardeniers, Han; Mul, Guido; Huskens, Jurriaan</p> <p>2016-02-17</p> <p>The spatioselective functionalization of silicon microwires with axial <span class="hlt">p/n</span> junctions is achieved using the electronic properties of the junction. (Photo)electrochemical deposition of metals is demonstrated at the bottom and top of the wires in the dark and light, respectively. The junction depletion layer remains unmodified, which allows its visualization and comparison with theoretical calculations. PMID:26866621</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830007547','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830007547"><span id="translatedtitle">Diffused <span class="hlt">P+-N</span> solar cells in bulk GaAs</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Borrego, J. M.; Ghandhi, S. K.</p> <p>1982-01-01</p> <p>Recently melt grown GaAs, made by liquid encapsulation techniques, has become available. This material is of sufficiently good quality to allow the fabrication of solar cells by direct diffusion. Results obtained with <span class="hlt">p(+)/n</span> junction solar cells made by zinc diffusion are described. The quality of bulk GaAs for this application is evaluated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770011613','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770011613"><span id="translatedtitle">Studies of silicon <span class="hlt">p-n</span> junction solar cells. [open circuit photovoltage</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lindholm, F. A.</p> <p>1976-01-01</p> <p>Single crystal silicon <span class="hlt">p-n</span> junction solar cells made with low resistivity substrates show poorer solar energy conversion efficiency than traditional theory predicts. The physical mechanisms responsible for this discrepancy are identified and characterized. The open circuit voltage in shallow junction cells of about 0.1 ohm/cm substrate resistivity is investigated under AMO (one sun) conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JaJAP..55b7001Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JaJAP..55b7001Y"><span id="translatedtitle">Sensitive thermal microsensor with <span class="hlt">pn</span> junction for heat measurement of a single cell</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yamada, Taito; Inomata, Naoki; Ono, Takahito</p> <p>2016-02-01</p> <p>A sensitive thermal microsensor based on a <span class="hlt">pn</span> junction diode for heat measurements of biological single cells is developed and evaluated. Using a fabricated device, we demonstrated the heat measurement of a single brown fat cell. The principle of the sensor relies on the temperature dependence of the <span class="hlt">pn</span> junction diode resistance. This method has a capability of the highly thermal sensitivity by downsizing and the advantage of a simple experimental setup using electrical circuits without any special equipment. To achieve highly sensitive heat measurement of single cells, downsizing of the sensor is necessary to reduce the heat capacity of the sensor itself. The sensor with the <span class="hlt">pn</span> junction diode can be downsized by microfabrication. A bridge beam structure with the <span class="hlt">pn</span> junction diode as a thermal sensor is placed in vacuum using a microfludic chip to decrease the heat loss to the surroundings. A temperature coefficient of resistance of 1.4%/K was achieved. The temperature and thermal resolutions of the fabricated device are 1.1 mK and 73.6 nW, respectively. The heat measurements of norepinephrine stimulated and nonstimulated single brown fat cells were demonstrated, and different behaviors in heat generation were observed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4495417','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4495417"><span id="translatedtitle">Photocurrent generation in lateral graphene <span class="hlt">p-n</span> junction created by electron-beam irradiation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Yu, Xuechao; Shen, Youde; Liu, Tao; Wu, Tao (Tom); Jie Wang, Qi</p> <p>2015-01-01</p> <p>Graphene has been considered as an attractive material for optoelectronic applications such as photodetectors owing to its extraordinary properties, e.g. broadband absorption and ultrahigh mobility. However, challenges still remain in fundamental and practical aspects of the conventional graphene photodetectors which normally rely on the photoconductive mode of operation which has the drawback of e.g. high dark current. Here, we demonstrated the photovoltaic mode operation in graphene <span class="hlt">p-n</span> junctions fabricated by a simple but effective electron irradiation method that induces n-type doping in intrinsic p-type graphene. The physical mechanism of the junction formation is owing to the substrate gating effect caused by electron irradiation. Photoresponse was obtained for this type of photodetector because the photoexcited electron-hole pairs can be separated in the graphene <span class="hlt">p-n</span> junction by the built-in potential. The fabricated graphene <span class="hlt">p-n</span> junction photodetectors exhibit a high detectivity up to ~3 × 1010 Jones (cm Hz1/2 W−1) at room temperature, which is on a par with that of the traditional III–V photodetectors. The demonstrated novel and simple scheme for obtaining graphene <span class="hlt">p-n</span> junctions can be used for other optoelectronic devices such as solar cells and be applied to other two dimensional materials based devices. PMID:26152225</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22399158','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22399158"><span id="translatedtitle">Enhanced spin Seebeck effect in a germanene <span class="hlt">p-n</span> junction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zheng, Jun; Chi, Feng; Guo, Yong</p> <p>2014-12-28</p> <p>Spin Seebeck effect in a germanene <span class="hlt">p-n</span> junction is studied by using the nonequilibrium Green's function method combined with the tight-binding Hamiltonian. We find that the thermal bias ΔT can generate spin thermopower when a local exchange field is applied on one edge of the germanene nano-ribbon. The magnitude of the spin thermopower can be modulated by the potential drop across the two terminals of the <span class="hlt">p-n</span> junction. When the value of the potential drop is smaller than the spin-orbit interaction strength, the spin thermopower is enhanced by two orders of magnitude larger as compared to the case of zero <span class="hlt">p-n</span> voltage. Optimal temperature corresponding to maximum spin thermopower is insensitive to the potential drop. In the <span class="hlt">p-n</span> region, maximum spin thermopower can be obtained at relatively higher temperatures. When the value of the potential drop is larger than that of the spin-orbit interaction, however, the spin Seebeck effect decays rapidly with increasing potential drop or temperature. By optimizing the structure parameters, the magnitude of the spin thermopower can be remarkably enhanced due to the coexistence of the exchange field and the potential drop.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014NatCo...5E4651B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014NatCo...5E4651B"><span id="translatedtitle">Photovoltaic effect in few-layer black phosphorus <span class="hlt">PN</span> junctions defined by local electrostatic gating</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Buscema, Michele; Groenendijk, Dirk J.; Steele, Gary A.; van der Zant, Herre S. J.; Castellanos-Gomez, Andres</p> <p>2014-08-01</p> <p>In conventional photovoltaic solar cells, photogenerated carriers are extracted by the built-in electric field of a semiconductor <span class="hlt">PN</span> junction, defined by ionic dopants. In atomically thin semiconductors, the doping level can be controlled by the field effect, enabling the implementation of electrically tunable <span class="hlt">PN</span> junctions. However, most two-dimensional (2D) semiconductors do not show ambipolar transport, which is necessary to realize <span class="hlt">PN</span> junctions. Few-layer black phosphorus (b-P) is a recently isolated 2D semiconductor with direct bandgap, high mobility, large current on/off ratios and ambipolar operation. Here we fabricate few-layer b-P field-effect transistors with split gates and hexagonal boron nitride dielectric. We demonstrate electrostatic control of the local charge carrier type and density in the device. Illuminating a gate-defined <span class="hlt">PN</span> junction, we observe zero-bias photocurrents and significant open-circuit voltages due to the photovoltaic effect. The small bandgap of the material allows power generation for illumination wavelengths up to 940 nm, attractive for energy harvesting in the near-infrared.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25164986','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25164986"><span id="translatedtitle">Photovoltaic effect in few-layer black phosphorus <span class="hlt">PN</span> junctions defined by local electrostatic gating.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Buscema, Michele; Groenendijk, Dirk J; Steele, Gary A; van der Zant, Herre S J; Castellanos-Gomez, Andres</p> <p>2014-01-01</p> <p>In conventional photovoltaic solar cells, photogenerated carriers are extracted by the built-in electric field of a semiconductor <span class="hlt">PN</span> junction, defined by ionic dopants. In atomically thin semiconductors, the doping level can be controlled by the field effect, enabling the implementation of electrically tunable <span class="hlt">PN</span> junctions. However, most two-dimensional (2D) semiconductors do not show ambipolar transport, which is necessary to realize <span class="hlt">PN</span> junctions. Few-layer black phosphorus (b-P) is a recently isolated 2D semiconductor with direct bandgap, high mobility, large current on/off ratios and ambipolar operation. Here we fabricate few-layer b-P field-effect transistors with split gates and hexagonal boron nitride dielectric. We demonstrate electrostatic control of the local charge carrier type and density in the device. Illuminating a gate-defined <span class="hlt">PN</span> junction, we observe zero-bias photocurrents and significant open-circuit voltages due to the photovoltaic effect. The small bandgap of the material allows power generation for illumination wavelengths up to 940 nm, attractive for energy harvesting in the near-infrared. PMID:25164986</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3961734','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3961734"><span id="translatedtitle">Bismuthoxyiodide Nanoflakes/Titania Nanotubes Arrayed <span class="hlt">p-n</span> Heterojunction and Its Application for Photoelectrochemical Bioanalysis</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Zhao, Wei-Wei; Liu, Zhao; Shan, Shu; Zhang, Wen-Wen; Wang, Jing; Ma, Zheng-Yuan; Xu, Jing-Juan; Chen, Hong-Yuan</p> <p>2014-01-01</p> <p>We have developed sensitive detection of cancer biomarker vascular endothelial growth factor (VEGF) using the <span class="hlt">p-n</span> heterojunction comprised of p-type BiOI nanoflakes (NFs) array and n-type TiO2 nanotubes (NTs) array. Due to the unique arrayed structure and the synergy effect of photoelectrochemistry in the formed <span class="hlt">p-n</span> junction, the synthesized configuration has superior excitation efficiency and thus excellent photoresponsibility. Then, the fabricated <span class="hlt">p-n</span> heterojunction was integrated with an exquisite bioassay protocol for addressing VEGF using a sandwich immunoassay with glucosedehydrogenase (GDH) as the enzyme tags. Due to the excellent performance of BiOI NFs array/TiO2 NTs array and the ingenious signaling mechanism, the proposed system could achieve the sensitive and specific VEGF detection. This work not only presents a simple BiOI NFs array/TiO2 NTs array <span class="hlt">p-n</span> heterojunction for general applications in the broad photochemistry areas, but also opens a different horizon for current development of advanced PEC biomolecular detection. PMID:24651880</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/pages/biblio/1248808-electrocatalytic-reduction-carbon-dioxide-well-defined-pn-ru-pincer-complex','SCIGOV-DOEP'); return false;" href="http://www.osti.gov/pages/biblio/1248808-electrocatalytic-reduction-carbon-dioxide-well-defined-pn-ru-pincer-complex"><span id="translatedtitle">Electrocatalytic Reduction of Carbon Dioxide with a Well-Defined <span class="hlt">PN</span> 3 -Ru Pincer Complex</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGESBeta</a></p> <p>Min, Shixiong; Rasul, Shahid; Li, Huaifeng; Grills, David C.; Takanabe, Kazuhiro; Li, Lain-Jong; Huang, Kuo-Wei</p> <p>2015-11-13</p> <p>We established a well-defined <span class="hlt">PN</span>3-Ru pincer complex (5) bearing a redox-active bipyridine ligand with an aminophosphine arm as an effective and stable molecular electrocatalyst for CO2 reduction to CO and HCOOH with negligible formation of H2 in a H2O/MeCN mixture.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JMP....56b3506D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JMP....56b3506D"><span id="translatedtitle">Constant curvature surfaces of the supersymmetric ℂ<span class="hlt">PN</span>-1 sigma model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Delisle, L.; Hussin, V.; Yurduşen, I.; Zakrzewski, W. J.</p> <p>2015-02-01</p> <p>Constant curvature surfaces are constructed from the finite action solutions of the supersymmetric ℂ<span class="hlt">PN</span>-1 sigma model. It is shown that there is a unique holomorphic solution which leads to constant curvature surfaces: the generalized Veronese curve. We give a general criterion to construct non-holomorphic solutions of the model. We extend our analysis to general supersymmetric Grassmannian models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=temperature&pg=6&id=EJ827974','ERIC'); return false;" href="http://eric.ed.gov/?q=temperature&pg=6&id=EJ827974"><span id="translatedtitle">Estimating <span class="hlt">p-n</span> Diode Bulk Parameters, Bandgap Energy and Absolute Zero by a Simple Experiment</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Ocaya, R. O.; Dejene, F. B.</p> <p>2007-01-01</p> <p>This paper presents a straightforward but interesting experimental method for <span class="hlt">p-n</span> diode characterization. The method differs substantially from many approaches in diode characterization by offering much tighter control over the temperature and current variables. The method allows the determination of important diode constants such as temperature…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008CQGra..25d5011R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008CQGra..25d5011R"><span id="translatedtitle">Fokker Planck Rosenbluth-type equations for self-gravitating systems in the 1<span class="hlt">PN</span> approximation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ramos-Caro, Javier; González, Guillermo A.</p> <p>2008-02-01</p> <p>We present two formulations of Fokker Planck Rosenbluth-type (FPR) equations for many-particle self-gravitating systems, with first-order relativistic corrections in the post-Newtonian approach (1<span class="hlt">PN</span>). The first starts from a covariant Fokker Planck equation for a simple gas, introduced recently by Chacón-Acosta and Kremer (2007 Phys. Rev. E 76 021201). The second derivation is based on the establishment of an 1<span class="hlt">PN</span>-BBGKY hierarchy, developed systematically from the 1<span class="hlt">PN</span> microscopic law of force and using the Klimontovich Dupree (KD) method. We close the hierarchy by the introduction of a two-point correlation function that describes adequately the relaxation process. This picture reveals an aspect that is not considered in the first formulation: the contribution of ternary correlation patterns to the diffusion coefficients, as a consequence of the nature of 1<span class="hlt">PN</span> interaction. Both formulations can be considered as a generalization of the equation derived by Rezania and Sobouti (2000 Astron. Astrophys. 354 1110), to stellar systems where the relativistic effects of gravitation play a significant role.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1888187','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1888187"><span id="translatedtitle">Suppression of rat carotid lesion development by the calcium channel blocker <span class="hlt">PN</span> 200-110.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Handley, D. A.; Van Valen, R. G.; Melden, M. K.; Saunders, R. N.</p> <p>1986-01-01</p> <p>Balloon catheter damage of the rat carotid artery endothelium results in an extensive and reproducible neointimal lesion composed of smooth muscle cells and connective matrix. The authors have examined two calcium channel blockers, <span class="hlt">PN</span> 200-110 and PY 108-068, for their ability to inhibit neointimal lesion development in the rat carotid model. When given subcutaneously (1.0 mg/kg day) both compounds produced rapidly acting and long-lasting hypotension, reducing blood pressure 25-29%. At this dose given daily, <span class="hlt">PN</span> 200-110 reduced lesion cross-sectional area by 44%, compared with only 25% seen by PY 108-068, which suggests that the antiatherosclerotic effect may not be related to lowering of blood pressure. Furthermore, <span class="hlt">PN</span> 200-110 did not reduce the extent of platelet deposition (compared with controls) occurring at the denuded vessel surface 1 hour or 24 hours after balloon catheterization, which indicates that the inhibition of lesion development may not reflect an antiplatelet mechanism. The observed inhibition by <span class="hlt">PN</span> 200-110 may relate to mitogen responses of the smooth muscle cell in the vessel wall (migration and proliferation) involved in lesion progression after endothelial damage. Images Figure 3 Figure 4 PMID:2942038</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/2942038','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/2942038"><span id="translatedtitle">Suppression of rat carotid lesion development by the calcium channel blocker <span class="hlt">PN</span> 200-110.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Handley, D A; Van Valen, R G; Melden, M K; Saunders, R N</p> <p>1986-07-01</p> <p>Balloon catheter damage of the rat carotid artery endothelium results in an extensive and reproducible neointimal lesion composed of smooth muscle cells and connective matrix. The authors have examined two calcium channel blockers, <span class="hlt">PN</span> 200-110 and PY 108-068, for their ability to inhibit neointimal lesion development in the rat carotid model. When given subcutaneously (1.0 mg/kg day) both compounds produced rapidly acting and long-lasting hypotension, reducing blood pressure 25-29%. At this dose given daily, <span class="hlt">PN</span> 200-110 reduced lesion cross-sectional area by 44%, compared with only 25% seen by PY 108-068, which suggests that the antiatherosclerotic effect may not be related to lowering of blood pressure. Furthermore, <span class="hlt">PN</span> 200-110 did not reduce the extent of platelet deposition (compared with controls) occurring at the denuded vessel surface 1 hour or 24 hours after balloon catheterization, which indicates that the inhibition of lesion development may not reflect an antiplatelet mechanism. The observed inhibition by <span class="hlt">PN</span> 200-110 may relate to mitogen responses of the smooth muscle cell in the vessel wall (migration and proliferation) involved in lesion progression after endothelial damage. PMID:2942038</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1007829','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1007829"><span id="translatedtitle">P- and <span class="hlt">PN</span>-Doped Nanotubes for Ultrasensitive and Selective Molecular Detection</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cruz Silva, Eduardo; Terrones Maldonado, Humberto; Terrones Maldonado, Mauricio; Charlier, Jean Christophe; Meunier, Vincent; Sumpter, Bobby G; Munoz-Sandoval, Emilio; Lopez, Florentino</p> <p>2010-01-01</p> <p>A first-principles approach is used to establish that substitutional phosphorus atoms strongly modify the chemical properties of the surface of carbon nanotubes, creating highly-localized sites with specific affinity towards acceptor molecules. Phosphorus-nitrogen co-dopants have a similar effect for acceptor molecules, but the <span class="hlt">P-N</span> bond can also accept charge, resulting in affinity towards donor molecules. This molecular selectivity is illustrated in CO and NH3 adsorbed on <span class="hlt">PN</span> doped nanotubes, O2 on P-doped nanotubes, and NO2 and SO2 on both P- and <span class="hlt">PN</span>-doped nanotubes. The adsorption of different chemical species onto the doped nanotubes modifies the dopant-induced localized states, which subsequently alter electronic conductance. Although SO2 and CO adsorption cause minor shifts in electronic conductance; NH3, NO2, and O2 adsorptions induce the suppression of a conductance dip. Conversely, the adsorption of NO2 on <span class="hlt">PN</span>-doped nanotubes is accompanied with the appearance of an additional dip in conductance, correlated with a shift of the existing ones. Overall these changes in electric conductance provide an efficient way to detect selectively the presence of specific molecules. Additionally, the high oxidation potential of the P-doped nanotubes makes them good candidates for electrode materials in hydrogen fuel cells.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JCoPh.314..682Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JCoPh.314..682Z"><span id="translatedtitle">Moment closures based on minimizing the residual of the <span class="hlt">PN</span> angular expansion in radiation transport</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zheng, Weixiong; McClarren, Ryan G.</p> <p>2016-06-01</p> <p>In this work we present two new closures for the spherical harmonics (<span class="hlt">PN</span>) method in slab geometry transport problems. Our approach begins with an analysis of the squared-residual of the transport equation where we show that the standard truncation and diffusive closures do not minimize the residual of the <span class="hlt">PN</span> expansion. Based on this analysis we derive two models, a moment-limited diffusive (ML DN) closure and a transient <span class="hlt">PN</span> (TPN) closure that attempt to address shortcomings of common closures. The form of these closures is similar to flux-limiters for diffusion with the addition of a time-derivative in the definition of the closure. Numerical results on a pulsed plane source problem, the Gordian knot of slab-geometry transport problems, indicate that our new closure outperforms existing linear closures. Additionally, on a deep penetration problem we demonstrate that the TPN closure does not suffer from the artificial shocks that can arise in the MN entropy-based closure. Finally, results for Reed's problem demonstrate that the TPN solution is as accurate as the <span class="hlt">PN</span>+3 solution. We further extend the TPN closure to 2D Cartesian geometry. The line source test problem demonstrates the model effectively damps oscillations and negative densities.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24145425','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24145425"><span id="translatedtitle">Gate-tunable carbon nanotube-MoS2 heterojunction <span class="hlt">p-n</span> diode.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jariwala, Deep; Sangwan, Vinod K; Wu, Chung-Chiang; Prabhumirashi, Pradyumna L; Geier, Michael L; Marks, Tobin J; Lauhon, Lincoln J; Hersam, Mark C</p> <p>2013-11-01</p> <p>The <span class="hlt">p-n</span> junction diode and field-effect transistor are the two most ubiquitous building blocks of modern electronics and optoelectronics. In recent years, the emergence of reduced dimensionality materials has suggested that these components can be scaled down to atomic thicknesses. Although high-performance field-effect devices have been achieved from monolayered materials and their heterostructures, a <span class="hlt">p-n</span> heterojunction diode derived from ultrathin materials is notably absent and constrains the fabrication of complex electronic and optoelectronic circuits. Here we demonstrate a gate-tunable <span class="hlt">p-n</span> heterojunction diode using semiconducting single-walled carbon nanotubes (SWCNTs) and single-layer molybdenum disulfide as p-type and n-type semiconductors, respectively. The vertical stacking of these two direct band gap semiconductors forms a heterojunction with electrical characteristics that can be tuned with an applied gate bias to achieve a wide range of charge transport behavior ranging from insulating to rectifying with forward-to-reverse bias current ratios exceeding 10(4). This heterojunction diode also responds strongly to optical irradiation with an external quantum efficiency of 25% and fast photoresponse <15 μs. Because SWCNTs have a diverse range of electrical properties as a function of chirality and an increasing number of atomically thin 2D nanomaterials are being isolated, the gate-tunable <span class="hlt">p-n</span> heterojunction concept presented here should be widely generalizable to realize diverse ultrathin, high-performance electronics and optoelectronics. PMID:24145425</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22489064','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22489064"><span id="translatedtitle">Photocurrent spectroscopy of exciton and free particle optical transitions in suspended carbon nanotube <span class="hlt">pn</span>-junctions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chang, Shun-Wen; Theiss, Jesse; Hazra, Jubin; Aykol, Mehmet; Kapadia, Rehan; Cronin, Stephen B.</p> <p>2015-08-03</p> <p>We study photocurrent generation in individual, suspended carbon nanotube <span class="hlt">pn</span>-junction diodes formed by electrostatic doping using two gate electrodes. Photocurrent spectra collected under various electrostatic doping concentrations reveal distinctive behaviors for free particle optical transitions and excitonic transitions. In particular, the photocurrent generated by excitonic transitions exhibits a strong gate doping dependence, while that of the free particle transitions is gate independent. Here, the built-in potential of the <span class="hlt">pn</span>-junction is required to separate the strongly bound electron-hole pairs of the excitons, while free particle excitations do not require this field-assisted charge separation. We observe a sharp, well defined E{sub 11} free particle interband transition in contrast with previous photocurrent studies. Several steps are taken to ensure that the active charge separating region of these <span class="hlt">pn</span>-junctions is suspended off the substrate in a suspended region that is substantially longer than the exciton diffusion length and, therefore, the photocurrent does not originate from a Schottky junction. We present a detailed model of the built-in fields in these <span class="hlt">pn</span>-junctions, which, together with phonon-assistant exciton dissociation, predicts photocurrents on the same order of those observed experimentally.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009PhDT........84W&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009PhDT........84W&link_type=ABSTRACT"><span id="translatedtitle">Electronic transport in graphene: <span class="hlt">p-n</span> junctions, shot noise, and nanoribbons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Williams, James Ryan</p> <p>2009-12-01</p> <p>Novel, two-dimensional materials have allowed for the inception and elucidation of a plethora of physical phenomena. On such material, a hexagonal lattice of carbon atoms called graphene, is a unique, truly two-dimensional molecular conductor. This thesis describes six experiments that elucidate some interesting physical properties and technological applications of graphene, with an emphasis on graphene-based <span class="hlt">p-n</span> junctions. A technique for the creation of high-quality <span class="hlt">p-n</span> junctions of graphene is described. Transport measurements at zero magnetic field demonstrate local control of the carrier type and density bipolar graphene-based junctions. In the quantum Hall regime, new plateaus in the conductance are observed and explained in terms of mode mixing at the <span class="hlt">p-n</span> interface. Shot noise in unipolar and bipolar graphene devices is measured. A density-independent Fano factor is observed, contrary to theoretical expectations. Further, an independence on device geometry is also observed. The role of disorder on the measured Fano factor is discussed, and comparison to recent theory for disordered graphene is made. The effect of a two-terminal geometry, where the device aspect ratio is different from unity, is measured experimentally and analyzed theoretically. A method for extracting layer number from the conductance extrema is proposed. A method for a conformal mapping of a device with asymmetric contacts to a rectangle is demonstrated. Finally, possible origins of discrepancies between theory and experiment are discussed. Transport along <span class="hlt">p-n</span> junctions in graphene is reported. Enhanced transport along the junction is observed and attributed to states that exist at the <span class="hlt">p-n</span> interface. A correspondence between the observed phenomena at low-field and in the quantum Hall regime is observed. An electric field perpendicular to the junction is found to reduce the enhanced conductance at the <span class="hlt">p-n</span> junction. A corollary between the <span class="hlt">p-n</span> interface states and "snake states" in an</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24066547','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24066547"><span id="translatedtitle">[Relationships of wheat leaf stomatal traits with wheat <span class="hlt">yield</span> and drought-resistance].</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Shu-Guang; Li, Zhong-Qing; Jia, Shou-Shan; Sun, Dai-Zhen; Shi, Yu-Gang; Fan, Hua; Liang, Zeng-Hao; Jing, Rui-Lian</p> <p>2013-06-01</p> <p>Taking the DH population of wheat cultivar Hanxuan10/Lumai14 as test object, and by the methods of correlation analysis and path analysis, this paper studied the relationships of the flag leaf stomatal density (SD), stomatal length and width (SL and SW), stomatal conductance (g(s)), photosynthetic rate (<span class="hlt">P(n</span>)), and transpiration rate (T(r)) on the 10th and 20th day after anthesis with the <span class="hlt">yield</span> and the index of drought-resistance under the conditions of drought stress and normal irrigation. Under the two conditions, most of the test leaf traits on the 10th day after anthesis had less correlation with the <span class="hlt">yield</span> and the index of drought-resistance, whereas the leaf traits on the 20th day after anthesis had significant positive correlations with thousand kernel weight but less correlation with grain number per ear, grain <span class="hlt">yield</span> per plant, and index of drought-resistance. Path analysis showed that g(s), <span class="hlt">P(n</span>), and T(r) were the main factors affecting the grain <span class="hlt">yield</span> per plant (YPP) and the index of drought resistance (IDR), and the effects were stronger both in direct and in indirect ways. The direct and indirect effects of SD, SL, and SW on the YPP and IDR were lesser. Under both drought stress and normal irrigation, and on the 10th and 20th day after anthesis, there were significant correlations between SD and SL, and between SL and SW, g(s), <span class="hlt">P(n</span>), and Tr, but the correlations of SD and SL with g(s), <span class="hlt">P(n</span>), and T(r) changed with water condition or growth stage. Therefore, it would be not always a good means to select the leaf stomatal density and size as the targets for breeding to improve the leaf stomatal conductance, photosynthetic rate, and transpiration rate, and further, to promote the <span class="hlt">yield</span>. PMID:24066547</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRB..121.2004S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRB..121.2004S"><span id="translatedtitle">Uppermost mantle structure of the Australian continent from <span class="hlt">Pn</span> traveltime tomography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sun, Weijia; Kennett, B. L. N.</p> <p>2016-03-01</p> <p>Past studies of the seismic structure of the Australian continent have dominantly exploited surface wave tomography for the mantle, with seismic refraction, receiver functions, and ambient noise used for crustal structure. The 3-D structure has been summarized in the Australian Seismological Reference Model (AuSREM), for which the zone immediately below the crust is the least well characterized. <span class="hlt">Pn</span> traveltime tomography provides a way of improving structural information on the uppermost mantle across the continent. We have exploited waveforms from larger events across Australia recorded at both permanent and portable stations since 1993, supplemented by bulletin arrival times. To compensate for the large velocity contrasts, with much faster mantle wave speeds in the center and west, all events were relocated using the AuSREM model. After relocation, consistent patterns of traveltime residuals are obtained. We extract <span class="hlt">Pn</span> as the first arrival in the distance range 1.8° to 15°. We use the FMTOMO approach to invert the travel-time residuals to generate a P wave speed structure with a resolution of 3°×3°. There is strong heterogeneity in <span class="hlt">Pn</span> wave speed in the uppermost mantle across the continent. The fastest <span class="hlt">Pn</span> wave speed of 8.36 km/s beneath the Precambrian cratons of western and central Australia is 3.99% faster than the global ak135 model, and the slowest <span class="hlt">Pn</span> wave speed 7.66 km/s on the eastern margin is 4.74% slower. The slowest velocities in the uppermost mantle are found along the eastern margin of the Australian continent beneath the Phanerozoic orogenic belts, with links to Neogene volcanism.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..MAR.W2001P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..MAR.W2001P"><span id="translatedtitle">Optically Induced <span class="hlt">PN</span> Junction Diode and Photovoltaic Response on Ambipolar MoSe2 Field-effect Transistor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pradhan, Nihar; Lu, Zhengguang; Rhodes, Daniel; Terrones, Mauricio; Smirnov, Dmitry; Balicas, Luis</p> <p>2015-03-01</p> <p>Transition metal dichalcogenides (TMDs) have emerged as an attractive material for electronic and optoelectronic devices due to their sizable band gap, flexibility and reduced dimensionality, which makes them promising candidates for applications in translucent optoelectronics components, such as solar cells and light emitting diodes. Here, we present an optically induced diode like response and concomitant photovoltaic effect in few-atomic layers molybdenum diselenide (MoSe2) field-effect transistors. Compared to recently reported <span class="hlt">PN</span> junctions based on TMDs, ambipolar MoSe2 shows nearly ideal diode rectification under illumination, with a sizable photovoltaic efficiency. The observed light induced diode response under fixed gate voltage, <span class="hlt">yields</span> a maximum open circuit voltage 0.28V and short circuit current 230nA at 30uW incident laser power. The sense of current rectification can be altered by changing the polarity of the applied gate voltage (Vbg) . At Vbg = 0V the highest electrical power obtained is 175pW corresponding to a maximum photovoltaic efficiency of 0.01%. These values increased to 11nW and 0.05% under a Vbg = -7.5V. At an excitation voltage 1V we observed maximum photocurrent responsivity surpassing 100mA/W with corresponding external quantum efficiency ~ 30%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..MAR.G1013Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..MAR.G1013Y"><span id="translatedtitle">Wafer-scale arrayed <span class="hlt">p-n</span> junctions based on few-layer epitaxial GaTe</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yuan, Xiang; Tang, Lei; Hu, Weida; Xiu, Faxian</p> <p>2015-03-01</p> <p>Two dimensional (2D) materials have showed appealing applications in electronics and optoelectronics. Gapless graphene presents ultra-broadband and fast photoresponse while the 2D semiconducting MoS2 and GaTe exhibit highly sensitive and tunable responsivity to the visible light. However, the device <span class="hlt">yield</span> and its repeatability call for a further improvement of 2D materials to render large-scale uniformity. Here we report a layer-by-layer growth of the wafer-scale GaTe by molecular beam epitaxy. To develop the arrayed <span class="hlt">p-n</span> junctions, the few-layer GaTe was grew on three-inch Si wafers. The resultant diodes reveal good rectifying characteristics and photoresponse with maximum photodetection responsivity of 2.74 A/W and photovoltaic external quantum efficiency up to 62%. The photocurrent reaches saturation very fast within 22 μs and shows no sign of device degradation after 1.37 million cycles of operation. Most strikingly, such high performance has been achieved across the entire wafer, making the volume production of devices accessible. Finally, several photo-images was acquired by using these photodiodes with a reasonable contrast and resolution, demonstrating for the first time the potential for these 2D technology coming into the real life.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016PhRvD..93l4061M&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016PhRvD..93l4061M&link_type=ABSTRACT"><span id="translatedtitle">Gravitational-wave phasing for low-eccentricity inspiralling compact binaries to 3<span class="hlt">PN</span> order</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moore, Blake; Favata, Marc; Arun, K. G.; Mishra, Chandra Kant</p> <p>2016-06-01</p> <p>Although gravitational radiation causes inspiralling compact binaries to circularize, a variety of astrophysical scenarios suggest that binaries might have small but non-negligible orbital eccentricities when they enter the low-frequency bands of ground- and space-based gravitational-wave detectors. If not accounted for, even a small orbital eccentricity can cause a potentially significant systematic error in the mass parameters of an inspiralling binary [M. Favata, Phys. Rev. Lett. 112, 101101 (2014)]. Gravitational-wave search templates typically rely on the quasicircular approximation, which provides relatively simple expressions for the gravitational-wave phase to 3.5 post-Newtonian (<span class="hlt">PN</span>) order. Damour, Gopakumar, Iyer, and others have developed an elegant but complex quasi-Keplerian formalism for describing the post-Newtonian corrections to the orbits and waveforms of inspiralling binaries with any eccentricity. Here, we specialize the quasi-Keplerian formalism to binaries with low eccentricity. In this limit, the nonperiodic contribution to the gravitational-wave phasing can be expressed explicitly as simple functions of frequency or time, with little additional complexity beyond the well-known formulas for circular binaries. These eccentric phase corrections are computed to 3<span class="hlt">PN</span> order and to leading order in the eccentricity for the standard <span class="hlt">PN</span> approximants. For a variety of systems, these eccentricity corrections cause significant corrections to the number of gravitational-wave cycles that sweep through a detector's frequency band. This is evaluated using several measures, including a modification of the useful cycles. By comparing to numerical solutions valid for any eccentricity, we find that our analytic solutions are valid up to e0≲0.1 for comparable-mass systems, where e0 is the eccentricity when the source enters the detector band. We also evaluate the role of periodic terms that enter the phasing and discuss how they can be incorporated into some of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20040120533&hterms=dark+net&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Ddark%2Bnet','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20040120533&hterms=dark+net&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Ddark%2Bnet"><span id="translatedtitle">Elevated carbon dioxide influences <span class="hlt">yield</span> and photosynthetic responses of hydroponically-grown sweetpotato</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mortley, D.; Hill, J.; Loretan, P.; Bonsi, C.; Hill, W.; Hileman, D.; Terse, A.</p> <p>1996-01-01</p> <p>The response of 'TI-155' and 'Georgia Jet' sweetpotato cultivars to elevated CO2 concentrations of 400 (ambient), 750 and 1000 micromoles mol-1 were evaluated under controlled environment conditions using the nutrient film technique (NFT). Growth chamber conditions included photosynthetic photon flux (PPF) of 600 micromoles m-2 s-1, 14/10 light/dark period, and 70% +/- 5% RH. Plants were grown using a modified half-Hoagland nutrient solution with a pH range of 5.5-6.0 and an electrical conductivity of 0.12 S m-1. Gas exchange measurements were made using infrared gas analysis, an open-flow gas exchange system, and a controlled-climate cuvette. Photosynthetic (<span class="hlt">Pn</span>) measurements were made at CO2 ranges of 50 to 1000 micromoles mol-1. Storage root <span class="hlt">yield</span>/plant increased with CO2 up to 750 but declined at 1000 micromoles mol-1. Storage root dry matter (DM) and foliage dry weight increased with increasing CO2. Harvest index (HI) for both cultivars was highest at 750 micromoles mol-1. The PPF vs <span class="hlt">Pn</span> curves were typical for C3 plants with saturation occurring at approximately 600 micromoles m-2 s-1. CO2 concentration did not significantly influence net <span class="hlt">Pn</span>, transpiration, water-use-efficiency (WUE), and stomatal conductance. As measurement CO2 concentration increased, net <span class="hlt">Pn</span> and WUE increased while transpiration and stomatal conductance decreased.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22493910','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22493910"><span id="translatedtitle">Electrical/thermal transport and electronic structure of the binary cobalt pnictides Co<span class="hlt">Pn</span>{sub 2} (<span class="hlt">Pn</span> = As and Sb)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Goto, Yosuke Miyao, Syuhei; Kamihara, Yoichi; Matoba, Masanori</p> <p>2015-06-15</p> <p>We demonstrate the electrical and thermal transport properties of polycrystalline Co<span class="hlt">Pn</span>{sub 2} (<span class="hlt">Pn</span> = As and Sb) between 300 and 900 K. CoAs{sub 2} shows semiconducting electrical transport up to 900 K, while CoSb{sub 2} exhibits degenerate conduction. Sign inversion of the Seebeck coefficient is observed at ∼310 and ∼400 K for CoAs{sub 2} and CoSb{sub 2}, respectively. Thermal conductivity at 300 K is 11.7 Wm{sup −1}K{sup −1} for CoAs{sub 2} and 9.4 Wm{sup −1}K{sup −1} for CoSb{sub 2}. The thermoelectric power factor of CoAs{sub 2} is ∼10 μWcm{sup −1}K{sup −2}, although the dimensionless figure of merit is limited to ∼0.1 due to relatively high thermal conductivity. Using electronic structure calculations, the band gap value is calculated to be 0.55 eV for CoAs{sub 2} and 0.26 eV for CoSb{sub 2}.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MARH16010B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MARH16010B"><span id="translatedtitle">Optoelectronic devices based on MoTe2 <span class="hlt">p-n</span> junction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bie, Ya-Qing; Heuck, Mikkel; Furchi, Marco; Grosso, Gabriele; Zheng, Jiabao; Cao, Yuan; Navarro-Moratalla, Efren; Englund, Dirk; Jarillo-Herrero, Pablo</p> <p></p> <p>2D transition metal dichalcogenides (2D-TMD), such as MoS2, have been verified with many remarkable physical properties, which include an indirect to direct band transition as a function of thickness and a valley dependent spin polarization. One of the 2D-TMD family members, 2H-MoTe2 has been shown to be a direct bandgap semiconductor as a monolayer and bilayer with a near infrared (NIR) bandgap of about 1.1eV. However, optoelectronic devices based on MoTe2 were so far not experimentally demonstrated. Here, we will present a high on-off ratio MoTe2 <span class="hlt">p-n</span> junction enabled by a hexagonal boron nitride encapsulation technique. Our study of the MoTe2 <span class="hlt">p-n</span> junction devices sheds light on designing efficient NIR optoelectronic devices such as photodetectors and energy harvesting cells and light emitters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APExp...9b5201Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APExp...9b5201Z"><span id="translatedtitle">Construction of coaxial ZnSe/ZnO <span class="hlt">p-n</span> junctions and their photovoltaic applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Xiwei; Meng, Dan; Hu, Dan; Tang, Zhenjie; Niu, Xiaoping; Yu, Fengjun; Ju, Lin</p> <p>2016-02-01</p> <p>Coaxial ZnSe/ZnO nanostructures were fabricated by coating a ZnO thin film on the surface of presynthesized p-type ZnSe 1D nanostructures by a sputtering method. Owing to the n-type behavior of ZnO resulting from intrinsic defects, coaxial ZnSe/ZnO <span class="hlt">p-n</span> junctions were realized and showed a pronounced rectifying behavior. Photovoltaic devices based on the coaxial ZnSe/ZnO <span class="hlt">p-n</span> junction showed a power conversion efficiency of 1.24% and a large open-circuit voltage of 0.87 V under UV light. The large bandgaps of ZnSe and ZnO and the high quality of the ZnSe/ZnO interface were considered to be related to the high performance of the devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19850039890&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DP-n%2Bjunction','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19850039890&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DP-n%2Bjunction"><span id="translatedtitle">Effect of reabsorbed recombination radiation on the saturation current of direct gap <span class="hlt">p-n</span> junctions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Von Roos, O.; Mavromatis, H.</p> <p>1984-01-01</p> <p>The application of the radiative transfer theory for semiconductors to <span class="hlt">p-n</span> homojunctions subject to low level injection conditions is discussed. By virtue of the interaction of the radiation field with free carriers across the depletion layer, the saturation current density in Shockley's expression for the diode current is reduced at high doping levels. The reduction, due to self-induced photon generation, is noticeable for n-type material owing to the small electron effective mass in direct band-gap III-V compounds. The effect is insignificant in p-type material. At an equilibrium electron concentration of 2 x 10 to the 18th/cu cm in GaAs, a reduction of the saturation current density by 15 percent is predicted. It is concluded that realistic GaAs <span class="hlt">p-n</span> junctions possess a finite thickness.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19910070123&hterms=P-n+junction&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DP-n%2Bjunction','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19910070123&hterms=P-n+junction&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DP-n%2Bjunction"><span id="translatedtitle">High-voltage 6H-SiC <span class="hlt">p-n</span> junction diodes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Matus, L. G.; Powell, J. A.; Salupo, C. S.</p> <p>1991-01-01</p> <p>A chemical vapor deposition (CVD) process has been used to produce device structures of n- and p-type 6H-SiC epitaxial layers on commercially produced single-crystal 6H-SiC wafers. Mesa-style <span class="hlt">p-n</span> junction diodes were successfully fabricated from these device structures using reactive ion etching, oxide passivation, and electrical contact metallization techniques. When tested in air, the 6H-SiC diodes displayed excellent rectification characteristics up to the highest temperature tested, 600 C. To observe avalanche breakdown of the <span class="hlt">p-n</span> junction diodes, testing under a high-electrical-strength liquid was necessary. The avalanche breakdown voltage was 1000 V representing the highest reverse breakdown voltage to be reported for any CVD-grown SiC diode.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JMP....56k3506S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JMP....56k3506S"><span id="translatedtitle">Gauge theories on noncommutative ℂ<span class="hlt">PN</span> and Bogomol'nyi-Prasad-Sommerfield-like equations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sako, Akifumi; Suzuki, Toshiya; Umetsu, Hiroshi</p> <p>2015-11-01</p> <p>We give the Fock representation of a noncommutative ℂ<span class="hlt">PN</span> and gauge theories on it. The Fock representation is constructed based on star products given by deformation quantization with separation of variables and operators which act on states in the Fock space are explicitly described by functions of inhomogeneous coordinates on ℂ<span class="hlt">PN</span>. Using the Fock representation, we are able to discuss the positivity of Yang-Mills type actions and the minimal action principle. Bogomol'nyi-Prasad-Sommerfield (BPS)-like equations on noncommutative ℂP1 and ℂP2 are derived from these actions. There are analogies between BPS-like equations on ℂP1 and monopole equations on ℝ3 and BPS-like equations on ℂP2 and instanton equations on ℝ8. We discuss solutions of these BPS-like equations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvB..94h5408Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvB..94h5408Z"><span id="translatedtitle">Hidden quantum mirage by negative refraction in semiconductor <span class="hlt">P-N</span> junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Shu-Hui; Zhu, Jia-Ji; Yang, Wen; Lin, Hai-Qing; Chang, Kai</p> <p>2016-08-01</p> <p>We predict a robust quantum interference phenomenon in a semiconductor <span class="hlt">P-N</span> junction: with a local pump on one side of the junction, the response of a local probe on the other side behaves as if the disturbance emanates not from the pump but instead from its mirror image about the junction. This phenomenon follows from the matching of Fermi surfaces of the constituent materials, thus it is robust against the details of the junction (e.g., width, potential profile, and even disorder), in contrast to the widely studied anomalous focusing caused by negative refraction. The recently fabricated <span class="hlt">P-N</span> junctions in 2D semiconductors provide ideal platforms to explore this phenomenon and its applications to dramatically enhance charge and spin transport as well as carrier-mediated long-range correlation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatCo...6E8066M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatCo...6E8066M"><span id="translatedtitle">Edge mixing dynamics in graphene <span class="hlt">p-n</span> junctions in the quantum Hall regime</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Matsuo, Sadashige; Takeshita, Shunpei; Tanaka, Takahiro; Nakaharai, Shu; Tsukagoshi, Kazuhito; Moriyama, Takahiro; Ono, Teruo; Kobayashi, Kensuke</p> <p>2015-09-01</p> <p>Massless Dirac electron systems such as graphene exhibit a distinct half-integer quantum Hall effect, and in the bipolar transport regime co-propagating edge states along the <span class="hlt">p-n</span> junction are realized. Additionally, these edge states are uniformly mixed at the junction, which makes it a unique structure to partition electrons in these edge states. Although many experimental works have addressed this issue, the microscopic dynamics of electron partition in this peculiar structure remains unclear. Here we performed shot-noise measurements on the junction in the quantum Hall regime as well as at zero magnetic field. We found that, in sharp contrast with the zero-field case, the shot noise in the quantum Hall regime is finite in the bipolar regime, but is strongly suppressed in the unipolar regime. Our observation is consistent with the theoretical prediction and gives microscopic evidence that the edge states are uniquely mixed along the <span class="hlt">p-n</span> junction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22399012','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22399012"><span id="translatedtitle">Edge-channel interferometer at the graphene quantum Hall <span class="hlt">pn</span> junction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Morikawa, Sei; Moriya, Rai; Masubuchi, Satoru Machida, Tomoki; Watanabe, Kenji; Taniguchi, Takashi</p> <p>2015-05-04</p> <p>We demonstrate a quantum Hall edge-channel interferometer in a high-quality graphene <span class="hlt">pn</span> junction under a high magnetic field. The co-propagating p and n quantum Hall edge channels traveling along the <span class="hlt">pn</span> interface functions as a built-in Aharonov-Bohm-type interferometer, the interferences in which are sensitive to both the external magnetic field and the carrier concentration. The trajectories of peak and dip in the observed resistance oscillation are well reproduced by our numerical calculation that assumes magnetic flux quantization in the area enclosed by the co-propagating edge channels. Coherent nature of the co-propagating edge channels is confirmed by the checkerboard-like pattern in the dc-bias and magnetic-field dependences of the resistance oscillations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ApPhL.103a3901M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ApPhL.103a3901M"><span id="translatedtitle">Local detection of deep carrier traps in the <span class="hlt">pn</span>-junction of silicon solar cells</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mchedlidze, T.; Scheffler, L.; Weber, J.; Herms, M.; Neusel, J.; Osinniy, V.; Möller, C.; Lauer, K.</p> <p>2013-07-01</p> <p>Mesa-diodes, with fully preserved solar cell structure, were fabricated at various locations of silicon solar cell. Deep level transient spectroscopy was applied for detection of carrier traps in the mesa-diodes. The parameters of the traps suggest their relation to interstitial iron and/or iron-related complexes. The density of the traps sharply falls with the distance from the <span class="hlt">pn</span>-junction. Measurements using Schottky-diodes fabricated on top of the bulk substrate material of the cell, after etching off of the solar-cell structure, did not show the presence of the traps. The results suggest that defects, influencing the performance of solar cells, were formed in/near to the <span class="hlt">pn</span>-junctions during their fabrication. The possible origin of the defects will be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5629229','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5629229"><span id="translatedtitle">Influence of grain boundaries on recombination in polysilicon <span class="hlt">pn</span>-junction solar cells</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fossum, J.G.; Neugroschel, A.; Lindholm, F.A.; Mazer, J.A.</p> <p>1980-01-01</p> <p>The physics controlling recombination in polysilicon <span class="hlt">pn</span>-junction cells is described. Analytic models characterizing this recombination, whose parameters can be related directly to experiment, are developed. The analysis reveals that, in general, the description of intra-grain and grain-boundary recombination in a polysilicon solar cell requires the solution of a nonlinear, three-dimensional boundary-value problem. Cases of practical interest for which this problem is tractable are discussed. The analysis predicts an exp(qV/2kT) dependence (the reciprocal slope factor is exactly two) for carrier recombination at a grain boundary within the junction space-charge region of a non-illuminated, forward-biased cell. This result, and others of the analysis, are shown to be consistent with measured current-voltage characteristics of <span class="hlt">pn</span> junctions fabricated on polycrystalline silicon.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010JaJAP..49c1301K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010JaJAP..49c1301K"><span id="translatedtitle">Effects of Bulk Microdefects and Metallic Impurities on <span class="hlt">p-n</span> Junction Leakage Currents in Silicon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Kwang-Salk; Moon, Byeong-sam; Kang, Hee-Bok; Park, Jea-gun; Lee, Bo-Young</p> <p>2010-03-01</p> <p>The effects of bulk microdefects and metallic impurities on leakage currents at <span class="hlt">p-n</span> junctions have been evaluated quantitatively by relating leakage currents with bulk defects and metallic impurities, and the results are reported. Bulk defects and metallic impurities, which were introduced by appropriate thermal treatment and intentional contamination by spin-coating metal ion solutions onto the silicon surfaces, were shown to induce heavy leakage currents at <span class="hlt">p-n</span> junctions, which had been manufactured by boron implantation and phosphorus diffusion. We found the bulk microdefects to be critical in causing leakage currents to flow and propose that their measurements be used as a means for the determination of the bulk defect densities. Die failure rates were also used for the evaluation of the effects of metallic impurities such as Cu, Ni, and Fe on the leakage currents.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25574020','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25574020"><span id="translatedtitle">Ultrafast dynamics. Four-dimensional imaging of carrier interface dynamics in <span class="hlt">p-n</span> junctions.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Najafi, Ebrahim; Scarborough, Timothy D; Tang, Jau; Zewail, Ahmed</p> <p>2015-01-01</p> <p>The dynamics of charge transfer at interfaces are fundamental to the understanding of many processes, including light conversion to chemical energy. Here, we report imaging of charge carrier excitation, transport, and recombination in a silicon <span class="hlt">p-n</span> junction, where the interface is well defined on the nanoscale. The recorded images elucidate the spatiotemporal behavior of carrier density after optical excitation. We show that carrier separation in the <span class="hlt">p-n</span> junction extends far beyond the depletion layer, contrary to the expected results from the widely accepted drift-diffusion model, and that localization of carrier density across the junction takes place for up to tens of nanoseconds, depending on the laser fluence. The observations reveal a ballistic-type motion, and we provide a model that accounts for the spatiotemporal density localization across the junction. PMID:25574020</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1982ITCom..30.1027Y&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1982ITCom..30.1027Y&link_type=ABSTRACT"><span id="translatedtitle">A modified <span class="hlt">PN</span> code tracking loop - Its performance analysis and comparative evaluation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yost, R. A.; Boyd, R. W.</p> <p>1982-05-01</p> <p>A modified <span class="hlt">PN</span> code tracking loop (MCTL) has been reported by Yost and Boyd (1980). The MCTL makes it possible to reduce the hardware complexity of a noncoherent delay lock loop in multiple data rate applications. The MCTL utilizes the on-time or data channel as the reference. This concept eliminates the need for the traditional loop's sum channel (early signal plus late signal) and, hence, the hardware associated with that channel. This saving may be substantial if the channel were to be optimized for a number of different data rates. With the elimination of an entire IF channel, the MCTL complexity is nearly equivalent to the dithering loop for <span class="hlt">PN</span> code tracking considered by Hartmann (1974). However, the MCTL does not suffer the loss in tracking performance (with respect to the traditional loop) that the dithering loop experiences.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22412567','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22412567"><span id="translatedtitle">Thin-layer black phosphorous/GaAs heterojunction <span class="hlt">p-n</span> diodes</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gehring, Pascal; Urcuyo, Roberto; Duong, Dinh Loc; Burghard, Marko; Kern, Klaus</p> <p>2015-06-08</p> <p>Owing to its high carrier mobility and thickness-tunable direct band gap, black phosphorous emerges as a promising component of optoelectronic devices. Here, we evaluate the device characteristics of <span class="hlt">p-n</span> heterojunction diodes wherein thin black phosphorous layers are interfaced with an underlying, highly n-doped GaAs substrate. The <span class="hlt">p-n</span> heterojunctions exhibit close-to-ideal diode behavior at low bias, while under illumination they display a photoresponse that is evenly distributed over the entire junction area, with an external quantum efficiency of up to 10% at zero bias. Moreover, the observed maximum open circuit voltage of 0.6 V is consistent with the band gap estimated for a black phosphorous sheet with a thickness on the order of 10 nm. Further analysis reveals that the device performance is limited by the structural quality of the black phosphorous surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014APS..MARQ37006B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014APS..MARQ37006B"><span id="translatedtitle">Carbon nanotube- MoS2 <span class="hlt">p-n</span> junction: Fabrication and transport properties</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bhanu, Udai; Islam, Muahmmad; Khondaker, Saiful</p> <p>2014-03-01</p> <p>Integrating two different nanoscale semicondcutors of opposite carrier types are of great interest for many electronic and optical applications. Few layers molybdenum disulfide (MoS2) is an n-type semiconductor while semiconductoing single walled carbon nanotubes (SWNT) show p-type behavior. In this work, we demonstrate a simple technique for integrating these two semiconductors for fabricating a <span class="hlt">p-n</span> junction. Few layers MoS2 device were mechanically exfoliated from a single crystal of MoS2 and making electrical contact via electron beam lithography. Another pair of electrodes, which are orthogonal to MoS2 device, is deposited and semiconducting reach SWNT(s-SWNT) solution was dielectrophoretically assembled between the second pair of electrodes. The s-SWNT goes over the MoS2 and fabricates two <span class="hlt">p-n</span> junctions. We will discuss the electronic transport properties of the fabricated devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1982STIA...8423156S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1982STIA...8423156S"><span id="translatedtitle">On the majority carrier collection in p+<span class="hlt">pn</span>+ and n+pp+ silicon solar cells</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Singh, S. N.; Kotnala, R. K.; Jain, G. C.</p> <p></p> <p>The spectral responses of a few bifacial n+pp+ silicon solar cells of different thicknesses were measured to investigate the possibility of majority carrier collection in n+pp+ back surface field (BSF) and p+<span class="hlt">pn</span>+ front surface field (FSF) silicon solar cells. It has been found out that under low level conditions, any appreciable collection of photogenerated majority carriers has to be field aided. Therefore, under low level conditions, a substantial contribution of hole collection to the photocurrent density of a p+<span class="hlt">pn</span>+ or n+pp+ cell may come from the p+ or p region provided not only the concentration of photogenerated holes in that region is substantially large but there also exists an aiding built in electric field due to an impurity gradient. For high level conditions, however, holes can be collected from the uniformly doped p-base region with or without the help of an aiding electric field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000ApSS..159..210T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000ApSS..159..210T"><span id="translatedtitle">Nanometer-scale characterization of lateral <span class="hlt">p-n</span> + junction by scanning capacitance microscope</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tomiye, H.; Yao, T.</p> <p>2000-06-01</p> <p>Spatial variation of the local capacitance of a lateral <span class="hlt">p-n</span> + junction is measured at various sample biases by our home-made Scanning Capacitance Microscope (SCaM)/Atomic Force Microscope (AFM) which facilitates direct measurements of capacitance itself. Local Capacitance-Voltage ( C- V) characteristics are measured at the same time during scanning of the cantilever. It is found that the <span class="hlt">p-n</span> + junction boundary as measured by the SCaM moves toward the p-region at negative bias, and to the opposite direction at positive bias. The local C- V characteristics at around the boundary in the p-region show a low-frequency C- V curve, which in the n +-region or just at the boundary, high-frequency C- V curve. These "unusual" phenomena are well interpreted with the help of a device simulator like "VENUS-2D/B".</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015aris.confc0118K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015aris.confc0118K"><span id="translatedtitle">A Segmented Neutron Detector with a High Position Resolution for the (p,<span class="hlt">pn</span>) Reactions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kubota, Yuki; Sasano, Masaki; Uesaka, Tomohiro; Dozono, Masanori; Itoh, Masatoshi; Kawase, Shoichiro; Kobayashi, Motoki; Lee, CheongSoo; Matsubara, Hiroaki; Miki, Kenjiro; Miya, Hiroyuki; Ota, Shinsuke; Sekiguchi, Kimiko; Shima, Tatsushi; Taguchi, Takahiro; Tamii, Atsushi; Tang, Tsz Leung; Tokieda, Hiroshi; Wakasa, Tomotsugu; Wakui, Takashi; Yasuda, Jumpei; Zenihiro, Juzo</p> <p></p> <p>We are developing a neutron detector with a high position resolution to study the single particle properties of nuclei by the knockout (p,<span class="hlt">pn</span>) reaction at intermediate energies. We constructed a prototype detector consisting of plastic scintillating fibers and multi-anode photomultiplier tubes (PMTs). Test experiments using 200- and 70-MeV proton and 199-, 188-, 68-, and 50-MeV neutron were performed for characterizing its performance. Preliminary results show that a position resolution of about 3 mm at full-width at half-maximum (FWHM) is realized as designed. The resulting separation-energy resolution to be obtained for (p,<span class="hlt">pn</span>) measurement would be 1 MeV in FWHM, when the detector is used at a distance of 2 m from the target for measuring the neutron momentum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013APS..MAR.Z5007K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013APS..MAR.Z5007K"><span id="translatedtitle">Focused Laser Induced Spatially Controllable <span class="hlt">p-n</span> junction in Graphene Field-Effect Transistor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Young; Bae, Myung-Ho; Shu, Jung-Tak; Kim, Young; Ahn, Joung; Chun, Seung-Hyun; Park, Yun</p> <p>2013-03-01</p> <p>Tunable local doping on graphene is an important issue for future graphene-based electronics. Here we investigate a local doping effect by a focused laser irradiation and demonstrate a spatially controllable <span class="hlt">p-n</span> junction in graphene field-effect transistor. Scanning photocurrent microscopy with varying back-gate voltages reveals the local charge trap in gate oxide near the laser-irradiated region. This is manifested by itself as double peaks in resistance as a function of gate voltage in graphene device, where the region between the double peaks corresponds to the <span class="hlt">p-n</span> junction. Irradiation of a focused laser on graphene device suggests a new pave to spatially control the doping level, position and size of doped segment on graphene channel in a nondestructive way without high electrical bias, local gate electrode and chemical process. Korea Research Institute of Standards and Science</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002ApPhL..80.4378Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002ApPhL..80.4378Z"><span id="translatedtitle">Rectifying characteristic in all-perovskite oxide film <span class="hlt">p-n</span> junction with room temperature ferromagnetism</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Jun; Tanaka, Hidekazu; Kawai, Tomoji</p> <p>2002-06-01</p> <p>We fabricated an all-perovskite oxide <span class="hlt">p-n</span> junction comprised of hole-doped (p-) manganite La0.9Ba0.1MnO3 and electron-doped (n-) titanate Sr0.99La0.01TiO3 films. The junction showed good rectifying properties at both room temperature and low temperature in a simple structure without inserting an insulating layer. By optimizing junction fabrication conditions, a thin La0.9Ba0.1MnO3 layer in the junction exhibited room temperature ferromagnetism and metallic conduction, which may be modulated by carrier injection from the n-type layer under an electric field. These results indicate that this <span class="hlt">p-n</span> junction may be developed into functional, strongly correlated electronic devices able to work at room temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoRL..43.3143S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoRL..43.3143S"><span id="translatedtitle">Uppermost mantle structure beneath eastern China and its surroundings from <span class="hlt">Pn</span> and Sn tomography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sun, Weijia; Kennett, B. L. N.</p> <p>2016-04-01</p> <p>The <span class="hlt">Pn</span> and Sn residuals from regional events provide strong constraints on the structure and lithological characteristics of the uppermost mantle beneath eastern China and its surroundings. With the dense Chinese Digital Seismic Network in eastern China, separate <span class="hlt">Pn</span> and Sn tomographic inversions have been exploited to obtain P and S velocities at a resolution of 2° × 2° or better. The patterns of P velocities are quite consistent with the S velocities at depth of 50 and 60 km, but the amplitude of P wave speed anomalies are a little larger than those of S wave speed. The low P wave speed, high S wave speed, and low Vp/Vs ratio beneath the northern part of Ordos Basin are related to upwelling hot material. Abrupt changes in material properties are indicated from the rapid variations in the Vp/Vs ratio.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/793381','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/793381"><span id="translatedtitle"><span class="hlt">Yield</span> Improvement in Steel Casting (<span class="hlt">Yield</span> II)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Richard A. Hardin; Christoph Beckermann; Tim Hays</p> <p>2002-02-18</p> <p>This report presents work conducted on the following main projects tasks undertaken in the <span class="hlt">Yield</span> Improvement in Steel Casting research program: Improvement of Conventional Feeding and Risering Methods, Use of Unconventional <span class="hlt">Yield</span> Improvement Techniques, and Case Studies in <span class="hlt">Yield</span> Improvement. Casting trials were conducted and then simulated using the precise casting conditions as recorded by the participating SFSA foundries. These results present a statistically meaningful set of experimental data on soundness versus feeding length. Comparisons between these casting trials and casting trials performed more than forty years ago by Pellini and the SFSA are quite good and appear reasonable. Comparisons between the current SFSA feeding rules and feeding rules based on the minimum Niyama criterion reveal that the Niyama-based rules are generally less conservative. The niyama-based rules also agree better with both the trials presented here, and the casting trails performed by Pellini an d the SFSA years ago. Furthermore, the use of the Niyama criterion to predict centerline shrinkage for horizontally fed plate sections has a theoretical basis according to the casting literature reviewed here. These results strongly support the use of improved feeding rules for horizontal plate sections based on the Niyama criterion, which can be tailored to the casting conditions for a given alloy and to a desired level of soundness. The reliability and repeatability of ASTM shrinkage x-ray ratings was investigated in a statistical study performed on 128 x-rays, each of which were rated seven different times. A manual ''Feeding and Risering Guidelines for Steel Castings' is given in this final report. Results of casting trials performed to test unconventional techniques for improving casting <span class="hlt">yield</span> are presented. These use a stacked arrangement of castings and riser pressurization to increase the casting <span class="hlt">yield</span>. Riser pressurization was demonstrated to feed a casting up to four time s the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ERL.....7b4016L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ERL.....7b4016L"><span id="translatedtitle">Reckoning wheat <span class="hlt">yield</span> trends</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lin, M.; Huybers, P.</p> <p>2012-06-01</p> <p>Wheat <span class="hlt">yields</span> have increased approximately linearly since the mid-twentieth century across the globe, but stagnation of these trends has now been suggested for several nations. We present a new statistical test for whether a <span class="hlt">yield</span> time series has leveled off and apply it to wheat <span class="hlt">yield</span> data from 47 different regions to show that nearly half of the production within our sample has transitioned to level trajectories. With the major exception of India, the majority of leveling in wheat <span class="hlt">yields</span> occurs within developed nations—including the United Kingdom, France and Germany—whose policies appear to have disincentivized <span class="hlt">yield</span> increases relative to other objectives. The effects of climate change and of <span class="hlt">yields</span> nearing their maximum potential may also be important.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19780034377&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DP-n%2Bjunction','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19780034377&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DP-n%2Bjunction"><span id="translatedtitle">Nondestructive determination of the depth of planar <span class="hlt">p-n</span> junctions by scanning electron microscopy</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chi, J.-Y.; Gatos, H. C.</p> <p>1977-01-01</p> <p>A method was developed for measuring nondestructively the depth of planar <span class="hlt">p-n</span> junctions in simple devices as well as in integrated-circuit structures with the electron-beam induced current (EBIC) by scanning parallel to the junction in a scanning electron microscope (SEM). The results were found to be in good agreement with those obtained by the commonly used destructive method of lapping at an angle to the junction and staining to reveal the junction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19840040328&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DP-n%2Bjunction','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19840040328&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DP-n%2Bjunction"><span id="translatedtitle">Photovoltaic characteristics of diffused <span class="hlt">P/+N</span> bulk GaAs solar cells</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Borrego, J. M.; Keeney, R. P.; Bhat, I. B.; Bhat, K. N.; Sundaram, L. G.; Ghandhi, S. K.</p> <p>1982-01-01</p> <p>The photovoltaic characteristics of <span class="hlt">P(+)N</span> junction solar cells fabricated on bulk GaAs by an open tube diffusion technique are described in this paper.Spectral response measurements were analyzed in detail and compared to a computer simulation in order to determine important material parameters. It is projected that proper optimization of the cell parameters can increase the efficiency of the cells from 12.2 percent to close to 20 percent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JInst..11P4006R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JInst..11P4006R"><span id="translatedtitle">A <span class="hlt">pn</span>CCD-based, fast direct single electron imaging camera for TEM and STEM</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ryll, H.; Simson, M.; Hartmann, R.; Holl, P.; Huth, M.; Ihle, S.; Kondo, Y.; Kotula, P.; Liebel, A.; Müller-Caspary, K.; Rosenauer, A.; Sagawa, R.; Schmidt, J.; Soltau, H.; Strüder, L.</p> <p>2016-04-01</p> <p>We report on a new camera that is based on a <span class="hlt">pn</span>CCD sensor for applications in scanning transmission electron microscopy. Emerging new microscopy techniques demand improved detectors with regards to readout rate, sensitivity and radiation hardness, especially in scanning mode. The <span class="hlt">pn</span>CCD is a 2D imaging sensor that meets these requirements. Its intrinsic radiation hardness permits direct detection of electrons. The <span class="hlt">pn</span>CCD is read out at a rate of 1,150 frames per second with an image area of 264 x 264 pixel. In binning or windowing modes, the readout rate is increased almost linearly, for example to 4000 frames per second at 4× binning (264 x 66 pixel). Single electrons with energies from 300 keV down to 5 keV can be distinguished due to the high sensitivity of the detector. Three applications in scanning transmission electron microscopy are highlighted to demonstrate that the <span class="hlt">pn</span>CCD satisfies experimental requirements, especially fast recording of 2D images. In the first application, 65536 2D diffraction patterns were recorded in 70 s. STEM images corresponding to intensities of various diffraction peaks were reconstructed. For the second application, the microscope was operated in a Lorentz-like mode. Magnetic domains were imaged in an area of 256 x 256 sample points in less than 37 seconds for a total of 65536 images each with 264 x 132 pixels. Due to information provided by the two-dimensional images, not only the amplitude but also the direction of the magnetic field could be determined. In the third application, millisecond images of a semiconductor nanostructure were recorded to determine the lattice strain in the sample. A speed-up in measurement time by a factor of 200 could be achieved compared to a previously used camera system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AIPC.1129..403K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AIPC.1129..403K"><span id="translatedtitle">Study Of Radiation Spectrum Emitted From Local Regions In <span class="hlt">PN</span> Junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Krcal, Ondrej; Koktavy, Pavel; Trcka, Tomas</p> <p>2009-04-01</p> <p>The microplasma discharges in <span class="hlt">PN</span> junction local defect micro-regions are as a rule accompanied by the emission of light, as it has been reported by Chynoweth and McKay [1]. The emission of visible light can be observed on small regions on the surface of solar cells. This study deals with investigating the spectrum of emission and determines the wavelength with maximum intensity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JInst..11P1012S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JInst..11P1012S"><span id="translatedtitle">Controlled charge extraction—antiblooming capabilities in <span class="hlt">pn</span>CCD imaging sensors</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schmidt, J.; Hartmann, R.; Holl, P.; Huth, M.; Lutz, G.; Pietsch, U.; Ryll, H.; Send, S.; Simson, M.; Soltau, H.; Soltau, J.; Steigenhöfer, D.; Strüder, L.</p> <p>2016-01-01</p> <p>Blooming in a CCD occurs when the signal charges accumulating in a pixel exceed the pixel saturation level and spill over into adjacent pixels. They start to spill over the weakest threshold in the electric potential of the pixel structure resulting in a degradation of the spatial information. With antiblooming mechanisms, the spatial resolution of the incoming photons can be preserved, but the intensity information is lost in the overflowing pixels. For imaging experiments, relying on a precise image structure, the preservation of the spatial resolution at the expense of precise intensity information is a workable compromise. In contrast to insulated gate CCDs, notably MOSCCDs, the potential wells of the pixel array of a <span class="hlt">pn</span>CCD are created by <span class="hlt">p+n</span> junctions, allowing direct electric access to the pixel structure. This allows to directly drain off charges from the pixels and to define a drain level by applying the appropriate operation voltages. Charge packets from 1 000 to more than one billion signal electrons per readout frame were generated without observing a spillover into adjacent pixels. As soon as the saturation level of the pixel is reached, the excess charge carriers are removed through charge drains exclusively created with the modification of the electric potential of the <span class="hlt">pn</span>CCD by the operation voltages. No additional antiblooming structures were implemented in the device and the pixel full well capacity of approximately 300 000 electrons in standard operation mode was preserved. A physical model of the antiblooming mechanism of <span class="hlt">pn</span>CCDs with a pixel size of 75 μ m × 75 μ m was established by two-dimensional numerical device simulations and verified by experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016MNRAS.tmp.1142M&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016MNRAS.tmp.1142M&link_type=ABSTRACT"><span id="translatedtitle">The Effect of Tides on the Population of <span class="hlt">PN</span> from Interacting Binaries</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Madappatt, Niyas; De Marco, Orsola; Villaver, Eva</p> <p>2016-08-01</p> <p>We have used the tidal equations of Zahn to determine the maximum orbital distance at which companions are brought into Roche lobe contact with their giant primary, when the primary expands during the giant phases. This is a key step when determining the rates of interaction between giants and their companions. Our stellar structure calculations are presented as maximum radii reached during the red and asymptotic giant branch (RGB and AGB, respectively) stages of evolution for masses between 0.8 and 4.0 M⊙ (Z=0.001 - 0.04) and compared with other models to gauge the uncertainty on radii deriving from details of these calculations. We find overall tidal capture distances that are typically 1-4 times the maximum radial extent of the giant star, where companions are in the mass range from 1 MJ to a mass slightly smaller than the mass of the primary. We find that only companions at initial orbital separations between ˜320 and ˜630 R⊙ will be typically captured into a Roche lobe-filling interaction or a common envelope on the AGB. Comparing these limits with the period distribution for binaries that will make <span class="hlt">PN</span>, we deduce that in the standard scenario where all ˜1-8 M⊙ stars make a <span class="hlt">PN</span>, at most 2.5 per cent of all <span class="hlt">PN</span> should have a post-common envelope central star binary, at odds with the observational lower limit of 15-20 per cent. The observed over-abundance of post-interaction central stars of <span class="hlt">PN</span> cannot be easily explained considering the uncertainties. We examine a range of explanations for this discrepancy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016yCat..74140860K&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016yCat..74140860K&link_type=ABSTRACT"><span id="translatedtitle">VizieR Online Data Catalog: <span class="hlt">PN</span> towards Galactic bulge. [OIII] fluxes (Kovacevic+, 2011)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kovacevic, A. V.; Parker, Q. A.; Jacoby, G. H.; Sharp, R.; Miszalski, B.; Frew, D. J.</p> <p>2016-03-01</p> <p>We observed previously known and MASH <span class="hlt">PN</span> in a 10°x10° region towards the Galactic bulge using the Cerro-Tololo Inter-American Observatory (CTIO) 4-m Blanco Telescope in Chile with the MOSAIC-II CCD Imager. A total of ~95h of photometric imaging was conducted, spread over two observing runs: six nights throughout 2008 June 9-14 and five nights from 2009 June 27 to July 2. (3 data files).</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016SSEle.122...37K&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016SSEle.122...37K&link_type=ABSTRACT"><span id="translatedtitle">Abrupt <span class="hlt">PN</span> junctions: Analytical solutions under equilibrium and non-equilibrium</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khorasani, Sina</p> <p>2016-08-01</p> <p>We present an explicit solution of carrier and field distributions in abrupt <span class="hlt">PN</span> junctions under equilibrium. An accurate logarithmic numerical method is implemented and results are compared to the analytical solutions. Analysis of results shows reasonable agreement with numerical solution as well as the depletion layer approximation. We discuss extensions to the asymmetric junctions. Approximate relations for differential capacitance C-V and current-voltage I-V characteristics are also found under non-zero external bias.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20010086591&hterms=Marten&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DMarten','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20010086591&hterms=Marten&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DMarten"><span id="translatedtitle">Atmospheric Nitrogen Fluorescence <span class="hlt">Yield</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Adams, J. H., Jr.; Christl, M. J.; Fountain, W. F.; Gregory, J. C.; Martens, K. U.; Sokolsky, Pierre; Whitaker, Ann F. (Technical Monitor)</p> <p>2001-01-01</p> <p>Several existing and planned experiments estimate the energies of ultra-high energy cosmic rays from air showers using the atmospheric nitrogen fluorescence. The nitrogen fluorescence <span class="hlt">yield</span> from air shower electrons depends on the atmospheric composition. We will discuss the uncertainties in the fluorescence <span class="hlt">yield</span> form electrons in the real atmosphere and describe a concept for a small balloon payload to measure the atmospheric fluorescence <span class="hlt">yield</span> as a function of attitude.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22488526','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22488526"><span id="translatedtitle">The ZnO <span class="hlt">p-n</span> homojunctions modulated by ZnMgO barriers</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Yang, Jing-Jing; Fang, Qing-Qing Wang, Dan-Dan; Du, Wen-Han</p> <p>2015-04-15</p> <p>In this paper, we fabricated the ultrathin ZnO <span class="hlt">p-n</span> homojunctions, which modulated by ZnMgO asymmetrical double barriers (ADB). The ADB <span class="hlt">p-n</span> homojunctions displays step-like curve in the absorption spectrums, this is the first time that quantum confinement effect has been observed in the absorption spectrums at room temperature (RT). The Hall-effect data confirm there is 2-dimensional electron gas in the interface of the ZnMgO ADB <span class="hlt">p-n</span> junctions. The quantum confinement effect enhances the hall-mobility μ to 10{sup 3} cm{sup 2}V {sup −1}s{sup −1} based on the polarity of the films. There was no rectification property in the ZnO homojunctions with thickness of 250nm, however, when the ADB was added in the n-type layer of the homojunctions, it displays a typical Zener diode rectification property in the I-V curve.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25470380','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25470380"><span id="translatedtitle">Cross-stacked single-crystal organic nanowire <span class="hlt">p-n</span> nanojunction arrays by nanotransfer printing.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Park, Kyung Sun; Lee, Ki Seok; Kang, Chan-Mo; Baek, Jangmi; Han, Kyu Seok; Lee, Changhee; Koo Lee, Yong-Eun; Kang, Youngjong; Sung, Myung Mo</p> <p>2015-01-14</p> <p>We fabricated cross-stacked organic <span class="hlt">p-n</span> nanojunction arrays made of single-crystal 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-PEN) and fullerene (C60) nanowires as p-type and n-type semiconductors, respectively, by using a nanotransfer printing technique. Single-crystal C60 nanowires were synthesized inside nanoscale channels of a mold and directly transferred onto a desired position of a flexible substrate by a lubricant liquid layer. In the consecutive printing process, single-crystal TIPS-PEN nanowires were grown in the same way and then perpendicularly aligned and placed onto the C60 nanowire arrays, resulting in a cross-stacked single-crystal organic <span class="hlt">p-n</span> nanojunction array. The cross-stacked single-crystal TIPS-PEN/C60 nanowire <span class="hlt">p-n</span> nanojunction devices show rectifying behavior with on/off ratio of ∼ 13 as well as photodiode characteristic with photogain of ∼ 2 under a light intensity of 12.2 mW/cm(2). Our study provides a facile, solution-processed approach to fabricate a large-area array of organic crystal nanojunction devices in a desired arrangement for future nanoscale electronics. PMID:25470380</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22391969','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22391969"><span id="translatedtitle">Giant magnetoresistance modulated by magnetic field in graphene <span class="hlt">p-n</span> junction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Li, Yuan; Jalil, Mansoor B. A.; Zhou, Guanghui</p> <p>2014-11-10</p> <p>We investigate the tunneling transport across a graphene <span class="hlt">p-n</span> junction under the influence of a perpendicular magnetic field (B field). We observe a sideway deflection of the transmission profile, which can be quantitatively explained by invoking the classical Lorentz force. By considering the trajectory of the Dirac fermions along their cyclotron orbits, we analytically derive the incident angles for transmission across the graphene junction under a B field, as well as the critical magnetic field for full suppression of tunneling across the junction. These analytical predictions are consistent with the numerical results obtained via the non-equilibrium Green's function method. A stronger B-field conductance modulation is obtained for a <span class="hlt">p-n</span> as opposed to an n-n or p-p type graphene junction. The magnetic field also induces a forbidden region of almost zero transmission for electron energy close to the Dirac point, which can be utilized to achieve a giant magnetoresistance effect. Based on our analysis, we devise an optimal magneto-electrical transport modulation, which can potentially realize a giant magnetoresistance effect in graphene <span class="hlt">p-n</span> junction systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApPhL.108w2902M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApPhL.108w2902M"><span id="translatedtitle">Ballistic conductivity of graphene channel with <span class="hlt">p-n</span> junction at ferroelectric domain wall</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Morozovska, Anna N.; Eliseev, Eugene A.; Strikha, Maksym V.</p> <p>2016-06-01</p> <p>The influence of a ferroelectric domain wall on the ballistic conductance of a single-layer graphene channel in the graphene/physical gap/ferroelectric film heterostructure has been studied in the Wentzel-Kramers-Brillouin approximation. The self-consistent numerical simulation of the electric field and the space charge dynamics in the heterostructure, as well as the approximate analytical theory, show that the contact between the domain wall and the surface creates a <span class="hlt">p-n</span> junction in the graphene channel. We calculated that the carrier concentration induced in graphene by uncompensated ferroelectric dipoles originated from the abrupt spontaneous polarization change near the surface can reach values of about 1019 m-2, which are two orders of magnitude higher than those obtained for the graphene on non-ferroelectric substrates. Therefore, we predict that the graphene channel with the <span class="hlt">p-n</span> junction caused by the ferroelectric domain wall would be characterized by rather a high ballistic conductivity. Moreover, the graphene <span class="hlt">p-n</span> junction at the ferroelectric domain wall can be an excellent rectifier with a conductivity ratio of about 10 between the direct and reverse polarities of the applied voltage.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005EJASP2005..207H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005EJASP2005..207H"><span id="translatedtitle"><span class="hlt">PN</span> Sequence Preestimator Scheme for DS-SS Signal Acquisition Using Block Sequence Estimation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hyun, Kwangmin; Yoon, Dongweon; Park, Sang Kyu</p> <p>2005-12-01</p> <p>An [InlineEquation not available: see fulltext.]-sequence (<span class="hlt">PN</span> sequence) preestimator scheme for direct-sequence spread spectrum (DS-SS) signal acquisition by using block sequence estimation (BSE) is proposed and analyzed. The proposed scheme consists of an estimator and a verifier which work according to the <span class="hlt">PN</span> sequence chip clock, and provides not only the enhanced chip estimates with a threshold decision logic and one-chip error correction among the first [InlineEquation not available: see fulltext.] received chips, but also the reliability check of the estimates with additional decision logic. The probabilities of the estimator and verifier operations are calculated. With these results, the detection, the false alarm, and the missing probabilities of the proposed scheme are derived. In addition, using a signal flow graph, the average acquisition time is calculated. The proposed scheme can be used as a preestimator and easily implemented by changing the internal signal path of a generally used digital matched filter (DMF) correlator or any other correlator that has a lot of sampling data memories for sampled <span class="hlt">PN</span> sequence. The numerical results show rapid acquisition performance in a relatively good CNR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993NIMPA.326..129B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993NIMPA.326..129B"><span id="translatedtitle">First results with the <span class="hlt">pn</span>-CCD detector system for the XMM satellite mission</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bräuninger, H.; Danner, R.; Hauff, D.; Lechner, P.; Lutz, G.; Meidinger, N.; Pinotti, E.; Reppin, C.; Strüder, L.; Trümper, J.; Kendziorra, E.; Krämer, J.; Mohan, M.; Staubert, R.; Findeis, N.; Holl, P.; Kemmer, J.; von Zanthier, C.</p> <p>1993-03-01</p> <p>The <span class="hlt">pn</span>-CCD is a novel CCD type which is developed for fast X-ray imaging and spectroscopy for the X-ray Multi Mirror (XMM) satellite mission. Each 200 × 64 pixel large <span class="hlt">pn</span>-CCD unit with a sensitive area of 3 × 1 cm 2 is a fully depleted detector. Full depletion allows for high photon detection efficiency (> 90% in the energy range of 500 eV-10 keV), for a small input capacitance necessary for low noise signal measurements and for backward illumination. For good time resolution and low noise performance each of the 64 CCD channels is terminated with an integrated input-JFET for signal amplification. With the use of the CMOS Amplifier and Multiplexing Chip (CAMEX64B) it is possible to read out the 64 CCD channels in parallel before they are multiplexed and sent to an ADC. For the first time the system of a 64 channel <span class="hlt">pn</span>-CCD together with CAMEX64B readout, ADC conversion and data acquisition and storage has been brought into operation. First images of an 55Fe X-ray source are presented and discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/974298','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/974298"><span id="translatedtitle">Growth and electrical rectification in axial in-situ doped <span class="hlt">p-n</span> junction germanium nanowires</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Picraux, Samuel T; Dayeh, Shadi; Zaslavsky, Alexander; Le, Son T</p> <p>2009-01-01</p> <p>In this work, we demonstrate the vapor-liquid-solid (VLS) growth and electrical properties of axial in-situ doped <span class="hlt">p-n</span> junction Ge nanowires (NWs). In-situ doping of the NWs was accomplished by introducing dopant gases (diborane and phosphine) together with GeH{sub 4} in the growth process. By changing dopant sources during growth, a <span class="hlt">p-n</span> junction can be realized along the axis of the NWs. Metal contacts to the wires were defined using e-beam lithography patterning, followed by 100 nm Ni sputter deposition and lift-off. Four-point measurements of the fabricated devices at room temperature and at 77 K clearly show rectification with on/off current ratio up to two orders of magnitude when the bias is applied across the <span class="hlt">p-n</span> junction. The ideality factor of the junction current points to a significant generation-recombination contribution. The Ohmic characteristics in the p and n regions outside the junction make it possible to estimate the doping levels. We also observed backgate control of the NW junction current.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25430809','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25430809"><span id="translatedtitle">Organic donor-acceptor assemblies form coaxial <span class="hlt">p-n</span> heterojunctions with high photoconductivity.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Prasanthkumar, Seelam; Ghosh, Samrat; Nair, Vijayakumar C; Saeki, Akinori; Seki, Shu; Ajayaghosh, Ayyappanpillai</p> <p>2015-01-12</p> <p>The formation of coaxial <span class="hlt">p-n</span> heterojunctions by mesoscale alignment of self-sorted donor and acceptor molecules, important to achieve high photocurrent generation in organic semiconductor-based assemblies, remains a challenging topic. Herein, we show that mixing a p-type π gelator (TTV) with an n-type semiconductor (PBI) results in the formation of self-sorted fibers which are coaxially aligned to form interfacial <span class="hlt">p-n</span> heterojunctions. UV/Vis absorption spectroscopy, powder X-ray diffraction studies, atomic force microscopy, and Kelvin-probe force microscopy revealed an initial self-sorting at the molecular level and a subsequent mesoscale self-assembly of the resulted supramolecular fibers leading to coaxially aligned <span class="hlt">p-n</span> heterojunctions. A flash photolysis time-resolved microwave conductivity (FP-TRMC) study revealed a 12-fold enhancement in the anisotropic photoconductivity of TTV/PBI coaxial fibers when compared to the individual assemblies of the donor/acceptor molecules. PMID:25430809</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4555100','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4555100"><span id="translatedtitle">Temperature-Dependent Asymmetry of Anisotropic Magnetoresistance in Silicon <span class="hlt">p-n</span> Junctions</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Yang, D. Z.; Wang, T.; Sui, W. B.; Si, M. S.; Guo, D. W.; Shi, Z.; Wang, F. C.; Xue, D. S.</p> <p>2015-01-01</p> <p>We report a large but asymmetric magnetoresistance in silicon <span class="hlt">p-n</span> junctions, which contrasts with the fact of magnetoresistance being symmetric in magnetic metals and semiconductors. With temperature decreasing from 293 K to 100 K, the magnetoresistance sharply increases from 50% to 150% under a magnetic field of 2 T. At the same time, an asymmetric magnetoresistance, which manifests itself as a magnetoresistance voltage offset with respect to the sign of magnetic field, occurs and linearly increases with magnetoresistance. More interestingly, in contrast with other materials, the lineshape of anisotropic magnetoresistance in silicon <span class="hlt">p-n</span> junctions significantly depends on temperature. As temperature decreases from 293 K to 100 K, the width of peak shrinks from 90° to 70°. We ascribe these novel magnetoresistance to the asymmetric geometry of the space charge region in <span class="hlt">p-n</span> junction induced by the magnetic field. In the vicinity of the space charge region the current paths are deflected, contributing the Hall field to the asymmetric magnetoresistance. Therefore, the observed temperature-dependent asymmetry of magnetoresistance is proved to be a direct consequence of the spatial configuration evolution of space charge region with temperature. PMID:26323495</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24970684','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24970684"><span id="translatedtitle">FSHR polymorphism <span class="hlt">p.N</span>680S mediates different responses to FSH in vitro.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Casarini, Livio; Moriondo, Valeria; Marino, Marco; Adversi, Francesca; Capodanno, Francesco; Grisolia, Chiarina; La Marca, Antonio; La Sala, Giovanni Battista; Simoni, Manuela</p> <p>2014-08-01</p> <p>The single nucleotide polymorphism <span class="hlt">p.N</span>680S of the follicle-stimulating hormone (FSH) receptor (FSHR) is a discrete marker of ovarian response but previous in vitro studies failed to demonstrate differences in the response to FSH between N and S carrier cells. Here we demonstrate that <span class="hlt">p.N</span>680S mediates different kinetics of the response to FSH in vitro. Intracellular cAMP production is faster in <span class="hlt">p.N</span>680S N than in S homozygous human granulosa cells (45 versus 90 min to achieve the plateau, respectively; Mann-Whitney's U-test; p < 0.005; n = 4). Reflecting the cAMP kinetics, phospho-ERK1/2 and -CREB activation, AREG and STARD1 gene expressions and progesterone production were qualitatively and quantitatively different in N versus S homozygous cells. Finally, the blockade of ERK pathway by U0126 abolishes the genotype-mediated different effects on gene expression and progesterone production (Mann-Whitney's U-test; p ≥ 0.005; n = 3). PMID:24970684</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/pages/biblio/1285958-al00-pn-diode-breakdown-voltage-gt','SCIGOV-DOEP'); return false;" href="http://www.osti.gov/pages/biblio/1285958-al00-pn-diode-breakdown-voltage-gt"><span id="translatedtitle">Al00.3Ga0.7N <span class="hlt">PN</span> diode with breakdown voltage >1600 V</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGESBeta</a></p> <p>Allerman, A. A.; Armstrong, A. M.; Fischer, A. J.; Dickerson, J. R.; Crawford, M. H.; King, M. P.; Moseley, M. W.; Wierer, J. J.; Kaplar, R. J.</p> <p>2016-07-21</p> <p>Demonstration of Al00.3Ga0.7N <span class="hlt">PN</span> diodes grown with breakdown voltages in excess of 1600 V is reported. The total epilayer thickness is 9.1 μm and was grown by metal-organic vapour-phase epitaxy on 1.3-mm-thick sapphire in order to achieve crack-free structures. A junction termination edge structure was employed to control the lateral electric fields. A current density of 3.5 kA/cm2 was achieved under DC forward bias and a reverse leakage current <3 nA was measured for voltages <1200 V. The differential on-resistance of 16 mΩ cm2 is limited by the lateral conductivity of the n-type contact layer required by the front-surface contactmore » geometry of the device. An effective critical electric field of 5.9 MV/cm was determined from the epilayer properties and the reverse current–voltage characteristics. To our knowledge, this is the first aluminium gallium nitride (AlGaN)-based <span class="hlt">PN</span> diode exhibiting a breakdown voltage in excess of 1 kV. Finally, we note that a Baliga figure of merit (Vbr2/Rspec,on) of 150 MW/cm2 found is the highest reported for an AlGaN <span class="hlt">PN</span> diode and illustrates the potential of larger-bandgap AlGaN alloys for high-voltage devices.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26323495','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26323495"><span id="translatedtitle">Temperature-Dependent Asymmetry of Anisotropic Magnetoresistance in Silicon <span class="hlt">p-n</span> Junctions.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yang, D Z; Wang, T; Sui, W B; Si, M S; Guo, D W; Shi, Z; Wang, F C; Xue, D S</p> <p>2015-01-01</p> <p>We report a large but asymmetric magnetoresistance in silicon <span class="hlt">p-n</span> junctions, which contrasts with the fact of magnetoresistance being symmetric in magnetic metals and semiconductors. With temperature decreasing from 293 K to 100 K, the magnetoresistance sharply increases from 50% to 150% under a magnetic field of 2 T. At the same time, an asymmetric magnetoresistance, which manifests itself as a magnetoresistance voltage offset with respect to the sign of magnetic field, occurs and linearly increases with magnetoresistance. More interestingly, in contrast with other materials, the lineshape of anisotropic magnetoresistance in silicon <span class="hlt">p-n</span> junctions significantly depends on temperature. As temperature decreases from 293 K to 100 K, the width of peak shrinks from 90° to 70°. We ascribe these novel magnetoresistance to the asymmetric geometry of the space charge region in <span class="hlt">p-n</span> junction induced by the magnetic field. In the vicinity of the space charge region the current paths are deflected, contributing the Hall field to the asymmetric magnetoresistance. Therefore, the observed temperature-dependent asymmetry of magnetoresistance is proved to be a direct consequence of the spatial configuration evolution of space charge region with temperature. PMID:26323495</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011SPIE.8191E..13X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011SPIE.8191E..13X"><span id="translatedtitle">Uncooled IR sensor based on lateral polysilicon <span class="hlt">pn</span> junction diode: initial results</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xu, De-hui; Xiong, Bin; Wang, Yue-lin</p> <p>2011-08-01</p> <p>These days, uncooled IR image sensors utilizing MEMS technologies have been widely studied for night vision and temperature sensing. Compared with other uncooled IR image sensor, uncooled IR image sensor utilizing <span class="hlt">p-n</span> junction diode detector has merits of good CMOS compatibility, better mass-production, and better detecting uniformity. In this paper, we proposed a novel uncooled IR sensor based on lateral polysilicon <span class="hlt">p-n</span> junction diode. In the CMOS process, p-type polysilicon is used for PMOS gate electrode material, while n-type polysilicon is used for NMOS gate electrode material. Due to that polysilicon diode is adopted for sensing, the silicon substrate under the microstructure can be completely removed, and a better thermal isolation and a small thermal mass can be achieved. By using the FEM software Ansys, 3D models of the silicon diode and polysilicon diode have been built for thermal simulation. Simulation results verify that a better thermal isolation can be achieved for polysilicon diode. The device was fabricated by standard CMOS process and a XeF2 post-CMOS maskless dry etching step. Measurement results of the fabricated lateral polysilicon <span class="hlt">p-n</span> junction diode is also reported.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999SPIE.3765..184P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999SPIE.3765..184P"><span id="translatedtitle"><span class="hlt">PN</span>-CCD camera for XMM and ABRIXAS: design of the camera system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pfeffermann, Elmar; Braeuninger, Heinrich W.; Bihler, Edgar; Briel, Ulrich G.; Hippmann, Horst; Holl, Peter; Kemmer, Josef; Kendziorra, Eckhard; Kettenring, Guenther; Kretschmar, Baerbel; Kuster, Markus; Meidinger, Norbert; Metzner, Gerd; Pflueger, Bernhard; Reppin, Claus; Soltau, Heike; Stephan, Karl-Heinz; Strueder, Lothar; Truemper, Joachim; von Zanthier, Christoph</p> <p>1999-10-01</p> <p>The <span class="hlt">pn</span>-Charge Coupled Device (<span class="hlt">pn</span>-CCD) camera was developed as one of the focal plane instruments for the European Photon Imaging Camera on board the x-ray multi mirror mission. An identical camera was foreseen on board ABRIXAS, a German x-ray satellite. The <span class="hlt">pn</span>-CCD camera is an imaging x- ray detector for single photon counting, operating at a temperature below -80 degrees C. Due to a 0.3 mm depletion depth of the CCDs, the detector has a high quantum efficiency up to 15 keV. The effective area of the instrument is 6 cm X 6 cm with 12 CCDs monolithically integrated on a single silicon wafer. The camera includes a filter wheel with different filters for suppression of optical and UV light. A radioactive source provides an in- orbit calibration. In this paper we give an overview of the mechanical, thermal and electrical design of the instrument and a description of different readout and test modes. More detailed information about the performance and calibration of the instrument can be found in companion papers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005PhLB..610...31G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005PhLB..610...31G"><span id="translatedtitle">Detailed comparison of the pp→π+<span class="hlt">pn</span> and pp→π+d reactions at 951 MeV</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gem Collaboration; Abdel-Bary, M.; Budzanowski, A.; Chatterjee, A.; Ernst, J.; Hawranek, P.; Hinterberger, F.; Jha, V.; Kilian, K.; Kliczewski, S.; Kirillov, D.; Kolev, D.; Kravcikova, M.; Kutsarova, T.; Lesiak, M.; Lieb, J.; Machner, H.; Magiera, A.; Maier, R.; Martinska, G.; Nedev, S.; Niskanen, J.; Piskunov, N.; Prasuhn, D.; Protić, D.; von Rossen, P.; Roy, B. J.; Sitnik, I.; Siudak, R.; Smiechowicz, M.; Tsenov, R.; Ulicny, M.; Urban, J.; Vankova, G.; Wilkin, C.</p> <p>2005-03-01</p> <p>The positively charged pions produced in proton proton collisions at a beam momentum of 1640 MeV/c were measured in the forward direction with a high resolution magnetic spectrograph. The missing mass distribution shows the bound state (deuteron) clearly separated from the <span class="hlt">pn</span> continuum. Despite the very good resolution, there is no evidence for any significant production of the <span class="hlt">pn</span> system in the spin-singlet state. However, the σ(pp→π+<span class="hlt">pn</span>)/σ(pp→π+d) cross section ratio is about twice as large as that predicted from S-wave final-state-interaction theory and it is suggested that this is due to D-state effects in the <span class="hlt">pn</span> system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000031370','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000031370"><span id="translatedtitle">Acceptance Data Package: SXI Stepper Motor/Encoder. Aeroflex <span class="hlt">P/N</span> 16187. A; Engineering Drawings and Associated Lists</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1994-01-01</p> <p>Acceptance data package - engineering drawings and associated lists for fabrication, assembly and maintenance (cleaning, fluidized bed coating, bounding and staking) motor/encoded solar x-ray imager (SXI) (Aeroflex <span class="hlt">p/n</span> 16187) were given.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AIPC.1731l0025K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AIPC.1731l0025K"><span id="translatedtitle">Transparent CH3NH3SnCl3/Al-ZnO <span class="hlt">p-n</span> heterojunction diode</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kumar, Sunil; Ansari, Mohd. Zubair; Khare, Neeraj</p> <p>2016-05-01</p> <p>A p-type Organic inorganic tin chloride (CH3NH3SnCl3) perovskite thin film has been synthesized by solution method. An n-type 1% Al doped ZnO (AZO) film has been deposited on FTO substrate by ultrasonic assisted chemical vapor deposition technique. A transparent CH3NH3SnCl3/AZO <span class="hlt">p-n</span> heterojunction diode has been fabricated by spin coating technique. CH3NH3SnCl3/AZO <span class="hlt">p-n</span> heterojunction shows 75% transparency in the visible region. I-V characteristic of CH3NH3SnCl3/AZO <span class="hlt">p-n</span> heterojunction shows rectifying behavior of the diode. The diode parameters calculated as ideality factor η=2.754 and barrier height V= 0.76 eV. The result demonstrates the potentiality of CH3NH3SnCl3/AZO <span class="hlt">p-n</span> heterojunction for transparent electronics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21502779','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21502779"><span id="translatedtitle">What can be learned from binding energy differences about nuclear structure: The example of {delta}V{sub <span class="hlt">pn</span>}</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bender, M.</p> <p>2011-06-15</p> <p>We perform an analysis of a binding energy difference called {delta}V{sub <span class="hlt">pn</span>}(N,Z){identical_to}-(1/4)[E(Z,N)-E(Z,N-2)-E(Z-2,N)+E(Z-2,N-2)] in the framework of a realistic nuclear model. It has been suggested that {delta}V{sub <span class="hlt">pn</span>} values provide a sensitive probe of nuclear structure, and it has been put forward as a primary motivation for the measurement of specific nuclear masses. Using the angular momentum and particle-number projected generator coordinate method and the Skyrme interaction SLy4, we analyze the contribution brought to {delta}V{sub <span class="hlt">pn</span>} by static deformation and dynamic fluctuations around the mean-field ground state. Our method gives a good overall description of {delta}V{sub <span class="hlt">pn</span>} throughout the chart of nuclei with the exception of the anomaly related to the Wigner energy along the N=Z line. The main conclusions of our analysis of {delta}V{sub <span class="hlt">pn</span>}, which are at variance with its standard interpretation, are that (i) the structures seen in the systematics of {delta}V{sub <span class="hlt">pn</span>} throughout the chart of nuclei can be easily explained combining a smooth background related to the symmetry energy and correlation energies due to deformation and collective fluctuations, (ii) the characteristic pattern of {delta}V{sub <span class="hlt">pn</span>} having a much larger size for nuclei that add only particles or only holes to a doubly magic nucleus than for nuclei that add particles for one nucleon species and holes for the other is a trivial consequence of the asymmetric definition of {delta}V{sub <span class="hlt">pn</span>} and not due to a the different structure of these nuclei, (iii) {delta}V{sub <span class="hlt">pn</span>} does not provide a very reliable indicator for structural changes, (iv){delta}V{sub <span class="hlt">pn</span>} does not provide a reliable measure of the proton-neutron interaction in the nuclear energy density functional (EDF) or of that between the last filled orbits or of the one summed over all orbits, and (v) {delta}V{sub <span class="hlt">pn</span>} does not provide a conclusive benchmark for nuclear EDF methods that is superior or complementary to</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2013EGUGA..15.4891C&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2013EGUGA..15.4891C&link_type=ABSTRACT"><span id="translatedtitle">Uppermost mantle velocity from <span class="hlt">Pn</span> tomography in the Gulf of Aden</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Corbeau, Jordane; Rolandone, Frédérique; Leroy, Sylvie; Al-Lazki, Ali; Keir, Derek; Stuart, Graham; Stork, Anna</p> <p>2013-04-01</p> <p>We present an analysis of <span class="hlt">Pn</span> traveltimes to determine lateral variations of velocity in the uppermost mantle and crustal thickness beneath the Gulf of Aden and its margins. No detailed tomographic image of the entire Gulf of Aden was available. Previous tomographic studies covered the eastern Gulf of Aden and were thus incomplete or at a large scale with a too low resolution to see the lithospheric structures. From 1990 to 2010, 49206 <span class="hlt">Pn</span> arrivals were selected from the International Seismological Center catalogue. We also used temporary networks : YOCMAL (Young Conjugate Margins Laboratory) networks with broadband stations located in Oman, Yemen and Socotra from 2003 to 2011, and Djibouti network from 2009 to 2011. From these networks we picked <span class="hlt">Pn</span> arrivals and selected 4110 rays. Using a least-squares tomographic code (Hearn, 1996), these data were analyzed to solve for velocity variations in the mantle lithosphere. We perform different inversions for shorter and longer ray path data sets in order to separate the shallow and deep structure within the mantle lid. In the upper lid, zones of low velocity (7.7 km/s) around Sanaa, Aden, Afar, and along the Gulf of Aden are related to active volcanism. Off-axis volcanism and a regional melting anomaly in the Gulf of Aden area may be connected to the Afar plume, and explained by the model of channeling material away from the Afar plume along ridge-axis. Our study validates the channeling model and shows that the influence of the Afar hotspot may extend much farther eastwards along the Aden and Sheba ridges into the Gulf of Aden than previously believed. Still in the upper lid, high <span class="hlt">Pn</span> velocities (>8,2 km/s) are observed in Yemen and may be related to the presence of a magmatic underplating under the volcanic margin of Aden and under the Red Sea margins. In the lower lid, zones of low velocities are spatially located differently than in the upper lid. On the Oman margin, a low velocity zone (7.6 km/s) suggests deep partial</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999JGR...10413061S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999JGR...10413061S"><span id="translatedtitle">P wave detection thresholds, <span class="hlt">Pn</span> velocity estimates, and T wave location uncertainty from oceanic hydrophones</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Slack, Philip D.; Fox, Christopher G.; Dziak, Robert P.</p> <p>1999-06-01</p> <p>P wave arrivals recorded by the U.S. Navy's SOund SUrveillance System (SOSUS) hydrophone arrays were used to estimate earthquake detection thresholds and <span class="hlt">Pn</span> velocities in the northeast Pacific Ocean. The Navy hydrophones have been used successfully to detect and locate oceanic earthquakes using their waterborne acoustic tertiary (T) waves; however, use of these hydrophones for seismic body wave detection allows regional seismic analyses to be extended to the oceanic environment. The P wave detection threshold of the SOSUS hydrophones was quantified using the epicentral distance and magnitude of 250 northeast Pacific Ocean earthquakes. Earthquakes with body wave magnitudes as low as 2 have detectable P wave arrivals at epicentral distances of ≤500 km. Earthquakes with mb between 3.5 and 5 were detected ˜50% of the time at distances of 100-1500 km, while events with mb > 5 were all detected, even out to distances of 1000-1500 km. Both P and T wave hydrophone arrival times were used to estimate the epicenters of 100 earthquakes. The peak amplitude of the T wave coda and the onset of the P wave were used as the earthquake arrival times to estimate event locations. T wave arrival time residuals have a Gaussian distribution with zero mean, which implies that using T wave peak amplitude is consistent with using the P wave onset as the arrival time. There are typically ≤6 stations used to derive a T wave based location, hence location error ellipses are not well constrained. A Monte Carlo technique was employed to estimate T wave event location uncertainty. T wave locations have error bars of ˜1 km in latitude and longitude when >3 hydrophones are used for a location estimate. The detected P wave arrivals and earthquake locations were used to measure <span class="hlt">Pn</span> velocities. <span class="hlt">Pn</span> velocity values of 7.9 ± 0.1 and 8.0 ± 0.1 km/s were found for the Pacific and Juan de Fuca plates, respectively. A <span class="hlt">Pn</span> velocity of 7.5 ± 0.1 km/s was measured for rays traveling northward from the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=292370','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=292370"><span id="translatedtitle">Reed canarygrass <span class="hlt">yield</span> improvement</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>Reed canarygrass is well adapted to the northern USA. Eight cultivars and 72 accessions collected in rural landscapes from Iowa to New Hampshire were evaluated for <span class="hlt">yield</span>. Accessions produced on average 7% higher biomass <span class="hlt">yield</span> compared to existing cultivars. Naturalized populations of reed canarygras...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4854342','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4854342"><span id="translatedtitle">Peanut witches' broom (<span class="hlt">Pn</span>WB) phytoplasma-mediated leafy flower symptoms and abnormal vascular bundles development</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Liu, Chi-Te; Huang, Hsin-Mei; Hong, Syuan-Fei; Kuo-Huang, Ling-Long; Yang, Chiao-Yin; Lin, Yen-Yu; Lin, Chan-Pin; Lin, Shih-Shun</p> <p>2015-01-01</p> <p>The peanut witches' broom (<span class="hlt">Pn</span>WB) phytoplasma causes virescence symptoms such as phyllody (leafy flower) in infected peanuts. However, the obligate nature of phytoplasma limits the study of host-pathogen interactions, and the detailed anatomy of <span class="hlt">Pn</span>WB-infected plants has yet to be reported. Here, we demonstrate that 4′,6′-diamidino-2-phenylindole (DAPI) staining can be used to track <span class="hlt">Pn</span>WB infection. The DAPI-stained phytoplasma cells were observed in phloem/internal phloem tissues, and changes in vascular bundle morphology, including increasing pith rays and thinner cell walls in the xylem, were found. We also discerned the cell types comprising <span class="hlt">Pn</span>WB in infected sieve tube members. These results suggest that the presence of <span class="hlt">Pn</span>WB in phloem tissue facilitates the transmission of phytoplasma via sap-feeding insect vectors. In addition, <span class="hlt">Pn</span>WB in sieve tube members and changes in vascular bundle morphology might strongly promote the ability of phytoplasmas to assimilate nutrients. These data will help further an understanding of the obligate life cycle and host-pathogen interactions of phytoplasma. PMID:26492318</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/10860883','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/10860883"><span id="translatedtitle">Sequence analysis and genome organisation of poinsettia mosaic virus (<span class="hlt">Pn</span>MV) reveal closer relationship to marafiviruses than to tymoviruses.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bradel, B G; Preil, W; Jeske, H</p> <p>2000-06-01</p> <p>Sequence comparison and genome organisation of poinsettia mosaic virus (<span class="hlt">Pn</span>MV), a putative member of the tymoviruses, revealed a closer relationship to marafiviruses. The complete nucleotide sequence of <span class="hlt">Pn</span>MV was determined. The 6099-nt RNA genome encodes a putative 221-kDa polyprotein that lacks a stop codon between the replicase and the coat protein genes, as in most tymovirus RNAs. The genomic RNA has a poly(A) tail at its 3'-terminus in contrast to the tRNA-like structure found in the RNA of most tymoviruses, and no homology was observed to the conserved noncoding region of the tymoviral 3'-termini. The tymobox of <span class="hlt">Pn</span>MV, a 16-nt region of the subgenomic RNA (sgRNA) promoter shared by most tymoviruses, differs in 3 nt from the RNA sequence of tymoviruses but is identical to the sequence of marafiviruses. At least three sgRNAs were found in <span class="hlt">Pn</span>MV-infected Euphorbia pulcherrima and in isolated <span class="hlt">Pn</span>MV particles; one that is 650 nt long encodes the 21.4-kDa coat protein, and the others are about 3.5 and 1.7 kb and contain the 5'- and the 3'-terminal parts of genomic RNA, respectively. Like tymoviruses, <span class="hlt">Pn</span>MV particles sediment as top and bottom components. The particles of the top component contain the sgRNA (650 nt) encoding the coat protein, and those of bottom component contain both genomic and sgRNAs. PMID:10860883</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008NIMPB.266.4674T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008NIMPB.266.4674T"><span id="translatedtitle">Management of ISOLDE <span class="hlt">yields</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Turrión, M.; Eller, M.; Catherall, R.; Fraile, L. M.; Herman-Izycka, U.; Köster, U.; Lettry, J.; Riisager, K.; Stora, Th.</p> <p>2008-10-01</p> <p>Isotope <span class="hlt">yields</span> at ISOLDE are regularly measured online (with dedicated gamma and beta detectors) and off line by implantation and subsequent alpha-, beta- or gamma spectroscopy. The Java based measurement software, dedicated to tape station measurements, has been updated in order to automate <span class="hlt">yield</span> measurements and provide possibilities to repeat existing measurements. A procedure supported by dedicated programs was established to analyze data. The results are centrally stored and provide an interface to the existing ISOLDE <span class="hlt">yield</span> database. The present ISOLDE <span class="hlt">yield</span> database has been recently created and updated with a large number of <span class="hlt">yields</span> compiled from published data. The database developed on ORACLE guarantees reliability and security and provides a simple way of compiling new information. A user oriented interface has been programmed allowing accessing the information via a web browser. Several levels in the database structure provide selective access to different layers of technical information for advanced users and for technical R&D. The improvements in the <span class="hlt">yield</span> measurement procedure, the data storage and accessibility, as well as the new database structure, the web application and the access interfaces, enhance the communication between technical information like <span class="hlt">yields</span> and the users of the ISOLDE facility.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.cdc.gov/tobacco/data_statistics/fact_sheets/tobacco_industry/low_yield_cigarettes/','NIH-MEDLINEPLUS'); return false;" href="http://www.cdc.gov/tobacco/data_statistics/fact_sheets/tobacco_industry/low_yield_cigarettes/"><span id="translatedtitle">Low-<span class="hlt">Yield</span> Cigarettes</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Secondhand Smoke Smokeless Products Youth Tobacco Prevention Tobacco Industry and Products Federal Tax Increase Tobacco Ingredient Reporting ... be used. 3 In the past, the tobacco industry categorized low-<span class="hlt">yield</span> cigarettes using measurements of tar ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27077886','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27077886"><span id="translatedtitle">δ-Ctenitoxin-<span class="hlt">Pn</span>1a, a Peptide from Phoneutria nigriventer Spider Venom, Shows Antinociceptive Effect Involving Opioid and Cannabinoid Systems, in Rats.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Emerich, Bruna Luiza; Ferreira, Renata C M; Cordeiro, Marta N; Borges, Márcia Helena; Pimenta, Adriano M C; Figueiredo, Suely G; Duarte, Igor Dimitri G; de Lima, Maria Elena</p> <p>2016-04-01</p> <p><span class="hlt">Pn</span>Tx4(6-1), henceforth renamed δ-Ctenitoxin-<span class="hlt">Pn</span>1a (δ-CNTX-<span class="hlt">Pn</span>1a), a peptide from Phoneutria nigriventer spider venom, initially described as an insect toxin, binds to site 3 of sodium channels in nerve cord synaptosomes and slows down sodium current inactivation in isolated axons in cockroaches (Periplaneta americana). δ-CNTX-<span class="hlt">Pn</span>1a does not cause any apparent toxicity to mice, when intracerebroventricularly injected (30 μg). In this study, we evaluated the antinociceptive effect of δ-CNTX-<span class="hlt">Pn</span>1a in three animal pain models and investigated its mechanism of action in acute pain. In the inflammatory pain model, induced by carrageenan, δ-CNTX-<span class="hlt">Pn</span>1a restored the nociceptive threshold of rats, when intraplantarly injected, 2 h and 30 min after carrageenan administration. Concerning the neuropathic pain model, δ-CNTX-<span class="hlt">Pn</span>1a, when intrathecally administered, reversed the hyperalgesia evoked by sciatic nerve constriction. In the acute pain model, induced by prostaglandin E₂, intrathecal administration of δ-CNTX-<span class="hlt">Pn</span>1a caused a dose-dependent antinociceptive effect. Using antagonists of the receptors, we showed that the antinociceptive effect of δ-CNTX-<span class="hlt">Pn</span>1a involves both the cannabinoid system, through CB₁ receptors, and the opioid system, through μ and δ receptors. Our data show, for the first time, that δ-Ctenitoxin-<span class="hlt">Pn</span>1a is able to induce antinociception in inflammatory, neuropathic and acute pain models. PMID:27077886</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4848632','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4848632"><span id="translatedtitle">δ-Ctenitoxin-<span class="hlt">Pn</span>1a, a Peptide from Phoneutria nigriventer Spider Venom, Shows Antinociceptive Effect Involving Opioid and Cannabinoid Systems, in Rats</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Emerich, Bruna Luiza; Ferreira, Renata C. M.; Cordeiro, Marta N.; Borges, Márcia Helena; Pimenta, Adriano M. C.; Figueiredo, Suely G.; Duarte, Igor Dimitri G.; de Lima, Maria Elena</p> <p>2016-01-01</p> <p><span class="hlt">Pn</span>Tx4(6-1), henceforth renamed δ-Ctenitoxin-<span class="hlt">Pn</span>1a (δ-CNTX-<span class="hlt">Pn</span>1a), a peptide from Phoneutria nigriventer spider venom, initially described as an insect toxin, binds to site 3 of sodium channels in nerve cord synaptosomes and slows down sodium current inactivation in isolated axons in cockroaches (Periplaneta americana). δ-CNTX-<span class="hlt">Pn</span>1a does not cause any apparent toxicity to mice, when intracerebroventricularly injected (30 μg). In this study, we evaluated the antinociceptive effect of δ-CNTX-<span class="hlt">Pn</span>1a in three animal pain models and investigated its mechanism of action in acute pain. In the inflammatory pain model, induced by carrageenan, δ-CNTX-<span class="hlt">Pn</span>1a restored the nociceptive threshold of rats, when intraplantarly injected, 2 h and 30 min after carrageenan administration. Concerning the neuropathic pain model, δ-CNTX-<span class="hlt">Pn</span>1a, when intrathecally administered, reversed the hyperalgesia evoked by sciatic nerve constriction. In the acute pain model, induced by prostaglandin E2, intrathecal administration of δ-CNTX-<span class="hlt">Pn</span>1a caused a dose-dependent antinociceptive effect. Using antagonists of the receptors, we showed that the antinociceptive effect of δ-CNTX-<span class="hlt">Pn</span>1a involves both the cannabinoid system, through CB1 receptors, and the opioid system, through μ and δ receptors. Our data show, for the first time, that δ-Ctenitoxin-<span class="hlt">Pn</span>1a is able to induce antinociception in inflammatory, neuropathic and acute pain models. PMID:27077886</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840013851','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840013851"><span id="translatedtitle">Argentina wheat <span class="hlt">yield</span> model</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Callis, S. L.; Sakamoto, C.</p> <p>1984-01-01</p> <p>Five models based on multiple regression were developed to estimate wheat <span class="hlt">yields</span> for the five wheat growing provinces of Argentina. Meteorological data sets were obtained for each province by averaging data for stations within each province. Predictor variables for the models were derived from monthly total precipitation, average monthly mean temperature, and average monthly maximum temperature. Buenos Aires was the only province for which a trend variable was included because of increasing trend in <span class="hlt">yield</span> due to technology from 1950 to 1963.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840013852','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840013852"><span id="translatedtitle">Argentina soybean <span class="hlt">yield</span> model</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Callis, S. L.; Sakamoto, C.</p> <p>1984-01-01</p> <p>A model based on multiple regression was developed to estimate soybean <span class="hlt">yields</span> for the country of Argentina. A meteorological data set was obtained for the country by averaging data for stations within the soybean growing area. Predictor variables for the model were derived from monthly total precipitation and monthly average temperature. A trend variable was included for the years 1969 to 1978 since an increasing trend in <span class="hlt">yields</span> due to technology was observed between these years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840013855','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840013855"><span id="translatedtitle">Argentina corn <span class="hlt">yield</span> model</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Callis, S. L.; Sakamoto, C.</p> <p>1984-01-01</p> <p>A model based on multiple regression was developed to estimate corn <span class="hlt">yields</span> for the country of Argentina. A meteorological data set was obtained for the country by averaging data for stations within the corn-growing area. Predictor variables for the model were derived from monthly total precipitation, average monthly mean temperature, and average monthly maximum temperature. A trend variable was included for the years 1965 to 1980 since an increasing trend in <span class="hlt">yields</span> due to technology was observed between these years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008APS..MAR.K1188L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008APS..MAR.K1188L"><span id="translatedtitle">Temperature dependence of the InGa<span class="hlt">PN</span> conduction band structure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lin, K. I.; Wang, T. S.; Hwang, J. S.</p> <p>2008-03-01</p> <p>Material properties of III-N-V alloys, such as GaAsN, InGaAsN, and InGa<span class="hlt">PN</span>, have been intensively studied, because a small amount of nitrogen (N) incorporation results in very large bandgap bowing and dramatic change in the band structure.^1,2 Recently, temperature dependence of the parameters, i.e. the localized states energy EN introduced by an isolated N and the interaction potential V, of the band anticrossing (BAC) model in GaAsN epilayers has been reported.^3 These properties have never been studied for InGa<span class="hlt">PN</span>. In this work, temperature-dependent photoreflectance (PR) measurements are employed to characterize the conduction band structure of In0.54Ga0.46P1-yNy (y = 0 and 0.02) grown on GaAs substrates. The band gap and the upper subband E+ are observed in InGa<span class="hlt">PN</span> as predicted by the BAC model. To investigate the energetic positions of the features in the PR spectra, a Kramers-Kronig analysis is proposed. Based on these PR data and the BAC model, we find EN=2.054 eV and V=1.513 eV at 293 K. With decreasing temperature, the energy of EN shifts significantly to higher energies. Simultaneously, the interaction potential V between the N states and the host conduction band also rises to higher values. The thermal shifts of EN and V are dEN/dT -0.43 meV/K and dV/dT -0.67 meV/K, respectively. 1.APL 88, 031907 (2006). 2.APL 89, 192116 (2006). 3.APL 89, 202105 (2006).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940006912','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940006912"><span id="translatedtitle">Progress in <span class="hlt">p(+)n</span> InP solar cells fabricated by thermal diffusion</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Flood, D. J.; Brinker, D. J.; Weinberg, I.; Vargas, C.; Faur, Mircea; Faur, Maria; Goradia, C.; Goradia, M.; Fatemi, N. S.</p> <p>1993-01-01</p> <p>The performance results of our most recently thermally diffused InP solar cells using the <span class="hlt">p(+)n</span> (Cd,S) structures are presented. We have succeeded in fabricating cells with measured AMO, 25 C V(sub oc) exceeding 880 mV (bare cells) which to the best of our knowledge is higher than previously reported V(sub oc) values for any InP homojunction solar cells. The cells were fabricated by thinning the emitter, after Au-Zn front contacting, from its initial thickness of about 4.5 microns to about 0.6 microns. After thinning, the exposed surface of the emitter was passivated by a thin (approximately 50A) P-rich oxide. Based on the measured EQY and J(sub sc)-V(sub oc) characteristics of our experimental high V(sub oc) <span class="hlt">p(+)n</span> InP solar cells, we project that reducing the emitter thickness to 0.3 microns, using an optimized AR coating, maintaining the surface hole concentration of 3 x 10(exp 18)cm(sup -3), reducing the grid shadowing from actual 10.55 percent to 6 percent and reducing the contact resistance will increase the actual measured 12.57 percent AMO 25 C efficiency to about 20.1 percent. By using our state-of-the-art <span class="hlt">p(+)n</span> structures which have a surface hole concentration of 4 x 10(exp 18)cm(sup -3) and slightly improving the front surface passivation, an even higher practically achievable AMO, 25 C efficiency of 21.3 percent is projected.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22399316','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22399316"><span id="translatedtitle">Electrical and photovoltaic characteristics of MoS{sub 2}/Si <span class="hlt">p-n</span> junctions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hao, Lanzhong Liu, Yunjie Gao, Wei; Han, Zhide; Xue, Qingzhong; Zeng, Huizhong; Wu, Zhipeng; Zhu, Jun; Zhang, Wanli</p> <p>2015-03-21</p> <p>Bulk-like molybdenum disulfide (MoS{sub 2}) thin films were deposited on the surface of p-type Si substrates using dc magnetron sputtering technique and MoS{sub 2}/Si <span class="hlt">p-n</span> junctions were formed. The vibrating modes of E{sup 1}{sub 2g} and A{sub 1g} were observed from the Raman spectrum of the MoS{sub 2} films. The current density versus voltage (J-V) characteristics of the junction were investigated. A typical J-V rectifying effect with a turn-on voltage of 0.2 V was shown. In different voltage range, the electrical transporting of the junction was dominated by diffusion current and recombination current, respectively. Under the light illumination of 15 mW cm{sup −2}, the <span class="hlt">p-n</span> junction exhibited obvious photovoltaic characteristics with a short-circuit current density of 3.2 mA cm{sup −2} and open-circuit voltage of 0.14 V. The fill factor and energy conversion efficiency were 42.4% and 1.3%, respectively. According to the determination of the Fermi-energy level (∼4.65 eV) and energy-band gap (∼1.45 eV) of the MoS{sub 2} films by capacitance-voltage curve and ultraviolet-visible transmission spectra, the mechanisms of the electrical and photovoltaic characteristics were discussed in terms of the energy-band structure of the MoS{sub 2}/Si <span class="hlt">p-n</span> junctions. The results hold the promise for the integration of MoS{sub 2} thin films with commercially available Si-based electronics in high-efficient photovoltaic devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26359762','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26359762"><span id="translatedtitle">Chemical Visualization of a GaN <span class="hlt">p-n</span> junction by XPS.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Caliskan, Deniz; Sezen, Hikmet; Ozbay, Ekmel; Suzer, Sefik</p> <p>2015-01-01</p> <p>We report on an operando XPS investigation of a GaN diode, by recording the Ga2p3/2 peak position under both forward and reverse bias. Areal maps of the peak positions under reverse bias are completely decoupled with respect to doped regions and allow a novel chemical visualization of the <span class="hlt">p-n</span> junction in a 2-D fashion. Other electrical properties of the device, such as leakage current, resistivity of the domains are also tapped via recording line-scan spectra. Application of a triangular voltage excitation enables probing photoresponse of the device. PMID:26359762</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19850051494&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DP-n%2Bjunction','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19850051494&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DP-n%2Bjunction"><span id="translatedtitle">Fabrication of <span class="hlt">p(+)-n</span> junction GaAs solar cells by a novel method</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ghandhi, S. K.; Mathur, G.; Rode, H.; Borrego, J. M.</p> <p>1984-01-01</p> <p>A novel method for making <span class="hlt">p(+)-n</span> diffused junction GaAs solar cells, with the formation of a diffusion source, an anti-reflective coating, and a protective cover glass in a single chemical-vapor deposition operation is discussed. Consideration is given to device fabrication and to solar-cell characteristics. The advantages of the technique are that the number of process steps is kept to an absolute minimum, the fabrication procedure is low-cost, and the GaAs surface is protected during the entire operation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19930051034&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DP-n%2Bjunction','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19930051034&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DP-n%2Bjunction"><span id="translatedtitle">Charge collection at large angles of incidence. [exibited by <span class="hlt">p-n</span> junctions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mcnulty, P. J.; Beauvais, W. J.; Reed, R. A.; Roth, D. R.; Stassinopoulos, E. G.; Brucker, G. J.</p> <p>1992-01-01</p> <p>Charge collection exhibited by <span class="hlt">p-n</span> junctions, which have at least one small dimension, deviates from the geometric assumptions commonly used in SEU (single event upset) testing. The amount of charge collected did not increase with the secant of the angle of incidence. The number of events under the peak in the charge collection spectrum did not decrease as the cosine of the angle of incidence. Both the position of the peak and the number of events under the peak measured at a given angle of incidence depended upon which symmetry axis of the device was chosen to be the axis of rotation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhCS.709a2005K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhCS.709a2005K"><span id="translatedtitle">Laser processing for bevel termination of high voltage <span class="hlt">pn</span> junction in SiC</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kubiak, A.; Ruta, Ł.; Rosowski, A.; French, P.</p> <p>2016-04-01</p> <p>Proper edge termination of the <span class="hlt">p-n</span> junction in silicon carbide is a key requirement in the fabrication of discrete devices able to withstand high voltages in reverse polarization. Due to the hardness of SiC the creation of the bevel termination remains difficult using mechanical machining. The use of laser beam sources with medium wavelength (532 nm) gives new possibilities in the machining of the silicon carbide. The paper presents the fabrication of the bevel termination structure in SiC using a green DPSS laser equipped with scanner and dedicated rotating sample holder. Characterization of the resulting structures proves the high potential of the proposed approach.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19790038756&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DP-n%2Bjunction','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19790038756&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DP-n%2Bjunction"><span id="translatedtitle">On the determination of diffusion lengths by means of angle-lapped <span class="hlt">p-n</span> junctions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Von Roos, O.</p> <p>1979-01-01</p> <p>A standard procedure for determining the minority carrier diffusion length by means of SEM consists of scanning an angle-lapped surface of a <span class="hlt">p-n</span> junction and measuring the resulting short circuit current as a function of beam position. The present paper points out that the usual expression linking the short circuit current induced by the electron beam to the angle between the semiconductor surface and the junction plane is incorrect. The correct expression is discussed and it is noted that, for angles less than 10 deg, the new and the old expression are practically indistinguishable.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24751350','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24751350"><span id="translatedtitle">The radiation damage of crystalline silicon <span class="hlt">PN</span> diode in tritium beta-voltaic battery.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lei, Yisong; Yang, Yuqing; Liu, Yebing; Li, Hao; Wang, Guanquan; Hu, Rui; Xiong, Xiaoling; Luo, Shunzhong</p> <p>2014-08-01</p> <p>A tritium beta-voltaic battery using a crystalline silicon convertor composed of (100)Si/SiO2/Si3N4 film degrades remarkably with radiation from a high intensity titanium tritide film. Simulation and experiments were carried out to investigate the main factor causing the degradation. The radiation damages mainly comes from the x-ray emitted from the titanium tritide film and beta particle can relieve the damages. The x-ray radiation induced positive charges in the SiO2 film destroying the output property of the <span class="hlt">PN</span> diode with the induction of an electric field. PMID:24751350</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040142243','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040142243"><span id="translatedtitle">High Beginning-of-Life Efficiency <span class="hlt">p/n</span> InP Solar Cells</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hoffman, Richard W., Jr.; Fatemi, Navid S.; Weizer, Victor G.; Jenkins, Phillip P.; Ringel, Steven A.; Scheiman, David A.; Wilt, David M.; Brinker, David J.</p> <p>2004-01-01</p> <p>We have achieved a new record efficiency of 17.6%, (AM0) for a <span class="hlt">p/n</span> InP homo-epitaxy solar cell. In addition, we have eliminated a previously observed photo-degradation of cell performance, which was due to losses in J(sub sc). Cells soaked in AM0 spectrum at one-sun intensity for an hour showed no significant change in cell performance. We have discovered carrier passivation effects when using Zn as the p-type dopant in the OMVPE growth of InP and have found a method to avoid the unexpected effects which result from typical operation of OMVPE cell growth.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1985PhRvC..32.1966E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1985PhRvC..32.1966E"><span id="translatedtitle">Delta excitations in heavy nuclei induced by (3He,t) and (<span class="hlt">p,n</span>) reactions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Esbensen, H.; Lee, T.-S. H.</p> <p>1985-12-01</p> <p>Delta excitations in heavy nuclei, induced by charge exchange reactions, are studied using the surface response model. The residual pion-exchange interaction and the self-energy of the delta in a nuclear medium is included in the random-phase-approximation response. The peak position observed in (3He,t) reactions can be explained by the self-energy of the delta extracted from pion-nucleus scattering, and the magnitude of the cross section is consistent with Glauber theory. The comparison to (<span class="hlt">p,n</span>) data is reasonable; contributions from neutron decay of the delta, which are left out in the calculations, constitute a substantial experimental background.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008PhRvB..77w3402C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008PhRvB..77w3402C"><span id="translatedtitle">Valley-valve effect and even-odd chain parity in <span class="hlt">p-n</span> graphene junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cresti, Alessandro; Grosso, Giuseppe; Parravicini, Giuseppe Pastori</p> <p>2008-06-01</p> <p>We address the current blocking by a <span class="hlt">p-n</span> junction in a zigzag graphene ribbon by means of numerical and analytic investigations. Ribbons with superimposed gate potentials perfectly block the current in the energy range, where a single energy band is active in both the n and the p regions, if the number of carbon chains is even. In the same conditions, an odd number of chains allows current transmission. We interpret this even-odd valley-valve effect in terms of the underlying honeycomb topology and crystal structure symmetry.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4566124','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4566124"><span id="translatedtitle">Chemical Visualization of a GaN <span class="hlt">p-n</span> junction by XPS</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Caliskan, Deniz; Sezen, Hikmet; Ozbay, Ekmel; Suzer, Sefik</p> <p>2015-01-01</p> <p>We report on an operando XPS investigation of a GaN diode, by recording the Ga2p3/2 peak position under both forward and reverse bias. Areal maps of the peak positions under reverse bias are completely decoupled with respect to doped regions and allow a novel chemical visualization of the <span class="hlt">p-n</span> junction in a 2-D fashion. Other electrical properties of the device, such as leakage current, resistivity of the domains are also tapped via recording line-scan spectra. Application of a triangular voltage excitation enables probing photoresponse of the device. PMID:26359762</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Nanos...711611M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Nanos...711611M"><span id="translatedtitle">Lateral graphene <span class="hlt">p-n</span> junctions formed by the graphene/MoS2 hybrid interface</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meng, Jie; Song, Hua-Ding; Li, Cai-Zhen; Jin, Yibo; Tang, Lei; Liu, Dameng; Liao, Zhi-Min; Xiu, Faxian; Yu, Da-Peng</p> <p>2015-07-01</p> <p>Graphene/two-dimensional (2D) semiconductor heterostructures have been demonstrated to possess many advantages for electronic and optoelectronic devices. However, there are few reports about the utilization of a 2D semiconductor monolayer to tune the properties of graphene. Here, we report the fabrication and characterization of graphene <span class="hlt">p-n</span> junctions based on graphene/MoS2 hybrid interfaces. Monolayered graphene across the monolayered MoS2 boundary is divided into n-type regions on the MoS2 and p-type regions on the SiO2 substrate. Such van der Waals heterostructure based graphene <span class="hlt">p-n</span> junctions show good photoelectric properties. The photocurrent modulation of such devices by a single back gate is also demonstrated for the first time, which shows that the graphene on and off MoS2 regions have different responses to the gate voltage. Our results suggest that the atomic thin hybrid structure can remarkably extend the device applications.Graphene/two-dimensional (2D) semiconductor heterostructures have been demonstrated to possess many advantages for electronic and optoelectronic devices. However, there are few reports about the utilization of a 2D semiconductor monolayer to tune the properties of graphene. Here, we report the fabrication and characterization of graphene <span class="hlt">p-n</span> junctions based on graphene/MoS2 hybrid interfaces. Monolayered graphene across the monolayered MoS2 boundary is divided into n-type regions on the MoS2 and p-type regions on the SiO2 substrate. Such van der Waals heterostructure based graphene <span class="hlt">p-n</span> junctions show good photoelectric properties. The photocurrent modulation of such devices by a single back gate is also demonstrated for the first time, which shows that the graphene on and off MoS2 regions have different responses to the gate voltage. Our results suggest that the atomic thin hybrid structure can remarkably extend the device applications. Electronic supplementary information (ESI) available: More details on device fabrication, control</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880013204','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880013204"><span id="translatedtitle">Using Colored Stochastic Petri Net (CS-<span class="hlt">PN</span>) software for protocol specification, validation, and evaluation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zenie, Alexandre; Luguern, Jean-Pierre</p> <p>1987-01-01</p> <p>The specification, verification, validation, and evaluation, which make up the different steps of the CS-<span class="hlt">PN</span> software are outlined. The colored stochastic Petri net software is applied to a Wound/Wait protocol decomposable into two principal modules: request or couple (transaction, granule) treatment module and wound treatment module. Each module is specified, verified, validated, and then evaluated separately, to deduce a verification, validation and evaluation of the complete protocol. The colored stochastic Petri nets tool is shown to be a natural extension of the stochastic tool, adapted to distributed systems and protocols, because the color conveniently takes into account the numerous sites, transactions, granules and messages.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ApPhL.103z3303K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ApPhL.103z3303K"><span id="translatedtitle"><span class="hlt">pn</span>-homojunction organic solar cells formed in phase-separated co-deposited films</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kubo, Masayuki; Kaji, Toshihiko; Hiramoto, Masahiro</p> <p>2013-12-01</p> <p>Simultaneous control of the doping and phase-separation in organic co-deposited films consisting of metal-free phthalocyanine and fullerene was performed. The doping was used to form <span class="hlt">pn</span>-homojunctions in the phase-separated co-deposited films. The diffusion length of the minority carriers reached 0.3 μm allowing the fabrication of very thick cells up to 0.5 μm thick. It was shown that suppression of the interfacial recombination processes is crucial for obtaining cells with high performance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27420510','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27420510"><span id="translatedtitle">Uncooled CMOS terahertz imager using a metamaterial absorber and <span class="hlt">pn</span> diode.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Escorcia, Ivonne; Grant, James; Gough, John; Cumming, David R S</p> <p>2016-07-15</p> <p>We demonstrate a low-cost uncooled terahertz (THz) imager fabricated in a standard 180 nm CMOS process. The imager is composed of a broadband THz metamaterial absorber coupled with a diode microbolometer sensor where the <span class="hlt">pn</span> junction is used as a temperature sensitive device. The metamaterial absorber array is integrated in the top metallic layers of a six metal layer process allowing for complete monolithic integration of the metamaterial absorber and sensor. We demonstrate the capability of the detector for stand-off imaging applications by using it to form transmission and reflection images of a metallic object hidden in a manila envelope. PMID:27420510</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=111046','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=111046"><span id="translatedtitle">Genome sequences of Chlamydia trachomatis Mo<span class="hlt">Pn</span> and Chlamydia pneumoniae AR39</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Read, T. D.; Brunham, R. C.; Shen, C.; Gill, S. R.; Heidelberg, J. F.; White, O.; Hickey, E. K.; Peterson, J.; Utterback, T.; Berry, K.; Bass, S.; Linher, K.; Weidman, J.; Khouri, H.; Craven, B.; Bowman, C.; Dodson, R.; Gwinn, M.; Nelson, W.; DeBoy, R.; Kolonay, J.; McClarty, G.; Salzberg, S. L.; Eisen, J.; Fraser, C. M.</p> <p>2000-01-01</p> <p>The genome sequences of Chlamydia trachomatis mouse pneumonitis (Mo<span class="hlt">Pn</span>) strain Nigg (1 069 412 nt) and Chlamydia pneumoniae strain AR39 (1 229 853 nt) were determined using a random shotgun strategy. The Mo<span class="hlt">Pn</span> genome exhibited a general conservation of gene order and content with the previously sequenced C.trachomatis serovar D. Differences between C.trachomatis strains were focused on an ~50 kb ‘plasticity zone’ near the termination origins. In this region Mo<span class="hlt">Pn</span> contained three copies of a novel gene encoding a >3000 amino acid toxin homologous to a predicted toxin from Escherichia coli 0157:H7 but had apparently lost the tryptophan biosyntheis genes found in serovar D in this region. The C.pneumoniae AR39 chromosome was >99.9% identical to the previously sequenced C.pneumoniae CWL029 genome, however, comparative analysis identified an invertible DNA segment upstream of the uridine kinase gene which was in different orientations in the two genomes. AR39 also contained a novel 4524 nt circular single-stranded (ss)DNA bacteriophage, the first time a virus has been reported infecting C.pneumoniae. Although the chlamydial genomes were highly conserved, there were intriguing differences in key nucleotide salvage pathways: C.pneumoniae has a uridine kinase gene for dUTP production, Mo<span class="hlt">Pn</span> has a uracil phosphororibosyl transferase, while C.trachomatis serovar D contains neither gene. Chromosomal comparison revealed that there had been multiple large inversion events since the species divergence of C.trachomatis and C.pneumoniae, apparently oriented around the axis of the origin of replication and the termination region. The striking synteny of the Chlamydia genomes and prevalence of tandemly duplicated genes are evidence of minimal chromosome rearrangement and foreign gene uptake, presumably owing to the ecological isolation of the obligate intracellular parasites. In the absence of genetic analysis, comparative genomics will continue to provide insight into the virulence</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/909960','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/909960"><span id="translatedtitle">THREE-DIMENSIONAL FIELD MODELS FOR REVERSE BIASED <span class="hlt">P-N</span> JUNCTIONS.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>UBALDI,F.; POZZI, G.; FAZZINI, P.F.; BELEGGIA, M.</p> <p>2007-04-02</p> <p>In order to obtain reliable quantitative information on the electrostatic field associated with reverse-biased <span class="hlt">p-n</span> junctions and on the distribution of dopants, the physics of the so-called ''dead layer'' and the influence of charged oxide layers are of paramount importance. To this purpose, experimental observations near the edge of a TEM sample can be useful. In these conditions, however, phase computations required to interpret the experimental results are very challenging as the problem is intrinsically three-dimensional. In order to cope with this problem, a mixed analytical-numerical approach is presented and discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008PhRvB..78t5308L&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008PhRvB..78t5308L&link_type=ABSTRACT"><span id="translatedtitle">Disorder effects in the quantum Hall effect of graphene <span class="hlt">p-n</span> junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Jian; Shen, Shun-Qing</p> <p>2008-11-01</p> <p>The quantum Hall effect in graphene <span class="hlt">p-n</span> junctions is studied numerically with emphasis on the effect of disorder at the interface of two adjacent regions. Conductance plateaus are found to be attached to the intensity of the disorder and are accompanied by universal conductance fluctuations in the bipolar regime, which is in good agreement with theoretical predictions of the random matrix theory on quantum chaotic cavities. The calculated Fano factors can be used in an experimental identification of the underlying transport character.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999AcASn..40..400D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999AcASn..40..400D"><span id="translatedtitle">An investigation of the general relativistic (1<span class="hlt">PN</span>) hydrodynamics in DSX scheme.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dai, Yurong; Wu, Xuejun; Xu, Chongming</p> <p>1999-11-01</p> <p>In this paper the general relativistic (1<span class="hlt">PN</span>) hydrodynamics is established by means of DSX scheme in both local and global coordinates. The stress-energy tensor Tμν of ordinary fluids is calculated in terms of the software Maple, then the energy equation and Euler equation are got in DSX scheme after being reduced and trimmed. All these are done in local coordinates, and the result in global coordinates can be found through the transformation law. Finally, the energy equation and Euler equation in local coordinates in the case of perfect fluids are discussed. The result in global coordinates can be found in the same way.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011PhRvB..84t5315W&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011PhRvB..84t5315W&link_type=ABSTRACT"><span id="translatedtitle">Femtosecond optical excitation of coherent acoustic phonons in a piezoelectric <span class="hlt">p-n</span> junction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wen, Yu-Chieh; Chern, Gia-Wei; Lin, Kung-Hsuan; Yeh, Jeffrey Jarren; Sun, Chi-Kuang</p> <p>2011-11-01</p> <p>We present a theoretical model for the photogeneration of coherent acoustic phonons in a piezoelectric <span class="hlt">p-n</span> junction. In our model, the transport of photoexcited carriers is governed by the drift-diffusion equation, whereas the dynamics of acoustic phonons obeys a loaded string equation. Among various mechanisms, the piezoelectric coupling is found to dominate the acoustic-phonon generation process. The waveform of the photogenerated acoustic pulse is strongly influenced by the various dynamics of the photoexcited carriers, especially the picosecond hole drifting. Our calculation also confirms the crucial role of the built-in electric field in the formation of coherent acoustic phonons under optical excitations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/19905628','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/19905628"><span id="translatedtitle">Investigation of the exclusive 3He(e,e' <span class="hlt">pn</span>)1H reaction.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Middleton, D G; Annand, J R M; Antelo, M Ases; Ayerbe, C; Barneo, P; Baumann, D; Bermuth, J; Bernauer, J; Blok, H P; Böhm, R; Bosnar, D; Ding, M; Distler, M O; Friedrich, J; Llongo, J García; Glazier, D I; Golak, J; Glöckle, W; Grabmayr, P; Hehl, T; Heim, J; Hesselink, W H A; Jans, E; Kamada, H; Mañas, G Jover; Kohl, M; Lapikás, L; MacGregor, I J D; Martin, I; McGeorge, J C; Merkel, H; Merle, P; Monstad, K; Moschini, F; Müller, U; Nogga, A; Pérez-Benito, R; Pospischil, Th; Potokar, M; Rosner, G; Seimetz, M; Skibiński, R; de Vries, H; Walcher, Th; Watts, D P; Weinriefer, M; Weiss, M; Witała, H; Zihlmann, B</p> <p>2009-10-01</p> <p>Cross sections for the 3He(e,e' <span class="hlt">pn</span>)1H reaction were measured for the first time at energy transfers of 220 and 270 MeV for several momentum transfers ranging from 300 to 450 MeV/c. Cross sections are presented as a function of the momentum of the recoil proton and the momentum transfer. Continuum Faddeev calculations using the Argonne V18 and Bonn-B nucleon-nucleon potentials overestimate the measured cross sections by a factor 5 at low recoil proton momentum with the discrepancy becoming smaller at higher recoil proton momentum. PMID:19905628</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27101973','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27101973"><span id="translatedtitle">Flexible infrared detectors based on <span class="hlt">p-n</span> junctions of multi-walled carbon nanotubes.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Huang, Zhenlong; Gao, Min; Yan, Zhuocheng; Pan, Taisong; Liao, Feiyi; Lin, Yuan</p> <p>2016-05-14</p> <p>Different types of multi-walled carbon nanotubes (CNTs), synthesized by chemical vapor deposition, are used to fabricate infrared (IR) detectors on flexible substrates based on CNT <span class="hlt">p-n</span> junctions. It is found that this kind of detector is sensitive to infrared signals with a power density as low as 90 μW mm(-2) even at room temperature. Besides, unlike other devices, the detector with this unique structure can be bent for 100 cycles without any damage and its functionality does not degenerate once it recovers to the initial state. The results give a good reference for developing efficient, low-cost, and flexible IR detectors. PMID:27101973</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21260363','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21260363"><span id="translatedtitle">Current flow and potential efficiency of solar cells based on GaAs and GaSb <span class="hlt">p-n</span> junctions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Andreev, V. M.; Evstropov, V. V.; Kalinovsky, V. S. Lantratov, V. M.; Khvostikov, V. P.</p> <p>2009-05-15</p> <p>Dependence of the efficiency of single-junction and multijunction solar cells on the mechanisms of current flow in photoactive <span class="hlt">p-n</span> junctions, specifically on the form of the dark current-voltage characteristic J-V, has been studied. The resistanceless J-V{sub j} characteristic (with the series resistance disregarded) of a multijunction solar cell has the same shape as the characteristic of a single-junction cell: both feature a set of exponential portions. This made it possible to develop a unified analytical method for calculating the efficiency of singlejunction and multijunction solar cells. The equation relating the efficiency to the photogenerated current at each portion of the J-V{sub j} characteristic is derived. For <span class="hlt">p-n</span> junctions in GaAs and GaSb, the following characteristics were measured: the dark J-V characteristic, the dependence of the open-circuit voltage on the illumination intensity P-V{sub OC}, and the dependence of the luminescence intensity on the forward current L-J. Calculated dependences of potential efficiency (under idealized condition for equality to unity of external quantum <span class="hlt">yield</span>) on the photogenerated current for single-junction GaAs and GaSb solar cells and a GaAs/GaSb tandem are plotted. The form of these dependences corresponds to the shape of J-V{sub j} characteristics: there are the diffusion- and recombination-related portions; in some cases, the tunneling-trapping portion is also observed. At low degrees of concentration of solar radiation (C < 10), an appreciable contribution to photogenerated current is made by recombination component. It is an increase in this component in the case of irradiation with 6.78-MeV protons or 1-MeV electrons that brings about a decrease in the efficiency of conversion of unconcentrated solar radiation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24643776','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24643776"><span id="translatedtitle"><span class="hlt">p-n</span> junction CuO/BiVO₄ heterogeneous nanostructures: synthesis and highly efficient visible-light photocatalytic performance.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Wenzhong; Wang, Jun; Wang, Zhizhen; Wei, Xuanzhen; Liu, Li; Ren, Qingshan; Gao, Wenliang; Liang, Yujie; Shi, Honglong</p> <p>2014-05-14</p> <p>A new strategy via coupling a polyol route with an oxidation process has been developed to successfully synthesize <span class="hlt">p-n</span> junction CuO/BiVO4 heterogeneous nanostructures. The experimental results reveal that the as-prepared <span class="hlt">p-n</span> junction CuO/BiVO4 heterogeneous nanostructures exhibit much higher visible-light-driven photocatalytic activity for the degradation of model dye rhodamine B (RhB) than the pure BiVO4 nanocrystals. The photocatalytic degradation rate (C/C0) of the RhB for <span class="hlt">p-n</span> junction CuO/BiVO4 heterogeneous nanostructures is about two times higher than that of pure BiVO4 nanocrystals. The enhanced photocatalytic efficiency is attributed to a large number of <span class="hlt">p-n</span> junctions in CuO/BiVO4 heterogeneous nanostructures, which effectively reduces the recombination of electrons and holes by charge transfer from n-type BiVO4 to the attached p-type CuO nanoparticles. This work not only provides an efficient route to enhance the visible-light-driven photocatalytic activity of BiVO4, but also offers a new strategy for fabricating <span class="hlt">p-n</span> junction heterogeneous nanostructure photocatalysts, which are expected to show considerable potential application in solar-driven wastewater treatment and water splitting. PMID:24643776</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27351273','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27351273"><span id="translatedtitle">Tuning Chemical Potential Difference across Alternately Doped Graphene <span class="hlt">p-n</span> Junctions for High-Efficiency Photodetection.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lin, Li; Xu, Xiang; Yin, Jianbo; Sun, Jingyu; Tan, Zhenjun; Koh, Ai Leen; Wang, Huan; Peng, Hailin; Chen, Yulin; Liu, Zhongfan</p> <p>2016-07-13</p> <p>Being atomically thin, graphene-based <span class="hlt">p-n</span> junctions hold great promise for applications in ultrasmall high-efficiency photodetectors. It is well-known that the efficiency of such photodetectors can be improved by optimizing the chemical potential difference of the graphene <span class="hlt">p-n</span> junction. However, to date, such tuning has been limited to a few hundred millielectronvolts. To improve this critical parameter, here we report that using a temperature-controlled chemical vapor deposition process, we successfully achieved modulation-doped growth of an alternately nitrogen- and boron-doped graphene <span class="hlt">p-n</span> junction with a tunable chemical potential difference up to 1 eV. Furthermore, such <span class="hlt">p-n</span> junction structure can be prepared on a large scale with stable, uniform, and substitutional doping and exhibits a single-crystalline nature. This work provides a feasible method for synthesizing low-cost, large-scale, high efficiency graphene <span class="hlt">p-n</span> junctions, thus facilitating their applications in optoelectronic and energy conversion devices. PMID:27351273</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016JaJAP..55fGP02A&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016JaJAP..55fGP02A&link_type=ABSTRACT"><span id="translatedtitle">Design and fabrication of a 20 MHz <span class="hlt">pn</span>-diode silicon ring resonator with in-plane vibration mode</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Asahi, Yoichi; Tanigawa, Hiroshi; Nishino, Tomoki; Furutsuka, Takashi; Suzuki, Kenichiro</p> <p>2016-06-01</p> <p>In this paper, we report a new microelectromechanical system (MEMS) resonator based on the <span class="hlt">pn</span>-diode principle. The <span class="hlt">pn</span>-diode-based resonator can eliminate the narrow gap that conventional electrostatic MEMS resonators need between driving electrodes. This is expected to solve several serious problems related to fabrication, packaging, and lifetime. However, the resonators previously reported had <span class="hlt">pn</span>-diodes formed in the vertical direction. Because the resonant frequency is determined by the thickness of the resonator plate, the resonant frequency in formed resonators cannot be changed in the same chip. To solve this problem, we newly design a <span class="hlt">pn</span>-diode resonator with a lateral vibration. Because the resonant frequency is determined by plate width, this new resonator can provide various resonators with different frequencies in a chip, which is most suitable for the integration of MEMS resonators with electronic circuits. Our research objective at present is related to design and fabrication. By using a simulator, we design a ring resonator of 20 MHz. In the fabrication, we develop a technique of using ion implantation to form a 3-µm-thick <span class="hlt">pn</span>-diode. The results shown here are very useful for improving the MEMS resonators.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/20692849','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/20692849"><span id="translatedtitle">Investigation of <span class="hlt">pn</span> Correlations in {sup 4}Hep Interactions at a Momentum of 5 GeV/c</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Blinov, A.V.; Turov, V.F.; Chadeyeva, M.V.</p> <p>2005-08-01</p> <p>Proton-neutron correlations in {sup 4}Hep interactions are studied in an exclusive experiment by using a 2-m bubble chamber exposed to a 5-GeV/c beam of {alpha} particles (the kinetic energy of the protons in the nucleus rest frame is T{sub p} = 620 MeV). Data on the production of <span class="hlt">pn</span> pairs in 4{pi} geometry for three channels, where it is possible to reconstruct the neutron momentum unambiguously, are used to determine the <span class="hlt">pn</span> correlation function in {sup 4}Hep interactions. The experimental results are compared with the predictions of a modified Lednicky-Lyuboshitz model. The value obtained for the root-mean-square radius of the <span class="hlt">pn</span>-emission region is R{sub <span class="hlt">pn</span>} = 2.1 {+-} 0.3 fm. The dependence of the correlation function on the modulus of the total momentum of the emitted nucleon pair and on the direction of the momentum transfer is studied. An indication that the emission of a <span class="hlt">pn</span> pair proceeds predominantly through the production of a virtual deuteron is obtained.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/7247507','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/7247507"><span id="translatedtitle"><span class="hlt">Yield</span> threshold decision framework</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Judd, B.R.; Younker, L.W.; Hannon, W.J.</p> <p>1989-08-17</p> <p>The USA is developing a decision analysis framework for evaluating the relative value of lower <span class="hlt">yield</span> thresholds and related verification policies. The framework facilitates systematic analysis of the major issues in the <span class="hlt">yield</span> threshold decision. The framework can be used to evaluate options proposed either in the inter-agency process or in the negotiations. In addition, the framework can measure the importance of uncertainties and alternative judgments, and thereby determine the advantages of additional research. Since the model is explicit and quantitative, it provides a rational, defensible approach for reaching important treaty and verification decisions. 9 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26489362','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26489362"><span id="translatedtitle">Anisotropic photocurrent response at black phosphorus-MoS2 <span class="hlt">p-n</span> heterojunctions.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hong, Tu; Chamlagain, Bhim; Wang, Tianjiao; Chuang, Hsun-Jen; Zhou, Zhixian; Xu, Ya-Qiong</p> <p>2015-11-28</p> <p>We investigate the photocurrent generation mechanisms at a vertical <span class="hlt">p-n</span> heterojunction between black phosphorus (BP) and molybdenum disulfide (MoS2) flakes through polarization-, wavelength-, and gate-dependent scanning photocurrent measurements. When incident photon energy is above the direct band gap of MoS2, the photocurrent response demonstrates a competitive effect between MoS2 and BP in the junction region. In contrast, if the incident photon energy is below the band gap of MoS2 but above the band gap of BP, the photocurrent response at the <span class="hlt">p-n</span> junction exhibits the same polarization dependence as that at the BP-metal junction, which is nearly parallel to the MoS2 channel. This result indicates that the photocurrent signals at the MoS2-BP junction primarily result from the direct band gap transition in BP. These fundamental studies shed light on the knowledge of photocurrent generation mechanisms in vertical 2D semiconductor heterojunctions, offering a new way of engineering future two-dimensional materials based optoelectronic devices. PMID:26489362</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24608229','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24608229"><span id="translatedtitle">Solar-energy conversion and light emission in an atomic monolayer <span class="hlt">p-n</span> diode.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pospischil, Andreas; Furchi, Marco M; Mueller, Thomas</p> <p>2014-04-01</p> <p>The limitations of the bulk semiconductors currently used in electronic devices-rigidity, heavy weight and high costs--have recently shifted the research efforts to two-dimensional atomic crystals such as graphene and atomically thin transition-metal dichalcogenides. These materials have the potential to be produced at low cost and in large areas, while maintaining high material quality. These properties, as well as their flexibility, make two-dimensional atomic crystals attractive for applications such as solar cells or display panels. The basic building blocks of optoelectronic devices are <span class="hlt">p-n</span> junction diodes, but they have not yet been demonstrated in a two-dimensional material. Here, we report a <span class="hlt">p-n</span> junction diode based on an electrostatically doped tungsten diselenide (WSe2) monolayer. We present applications as a photovoltaic solar cell, a photodiode and a light-emitting diode, and obtain light-power conversion and electroluminescence efficiencies of ∼ 0.5% and ∼ 0.1%, respectively. Given recent advances in the large-scale production of two-dimensional crystals, we expect them to profoundly impact future developments in solar, lighting and display technologies. PMID:24608229</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ApPhL.101y3305I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ApPhL.101y3305I"><span id="translatedtitle">Scanning photocurrent and photoluminescence imaging of a frozen polymer <span class="hlt">p-n</span> junction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Inayeh, Alex; Dorin, Bryce; Gao, Jun</p> <p>2012-12-01</p> <p>A polymer light-emitting electrochemical cell (LEC) is a solid-state polymer device operating on in situ electrochemical doping and the formation of a light-emitting polymer <span class="hlt">p-n</span> junction. Electrochemical doping of the luminescence polymer quenches the photoluminescence. The chemical potential difference between the p- and n-doped regions creates a built-in potential/field in the junction region, which can be probed by measuring the optical beam induced current (OBIC). In this study, the OBIC and photoluminescence profiles of the LEC have been simultaneously measured by scanning a focused light beam across a large planar LEC that has been turned on and cooled to freeze the doping profile. The photoluminescence intensity undergoes a sharp transition between the p- and n-doped regions. The OBIC photocurrent is only observed in the transition region that is narrower than the width of the excitation beam, which is about 35 μm. The results depict a static planar polymer <span class="hlt">p-n</span> junction with a built-in field pointing from n to p. The electrode interface and the neutral regions do not produce a measurable photocurrent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3954071','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3954071"><span id="translatedtitle"><span class="hlt">p-n</span> Junction Photocurrent Modelling Evaluation under Optical and Electrical Excitation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Dervos, Constantine T.; Skafidas, Panayotis D.; Mergos, John A.; Vassiliou, Panayota</p> <p>2004-01-01</p> <p>Based upon the quasi-equilibrium approximation, the validity of <span class="hlt">p-n</span> junction modelling, has been experimentally investigated under synchronous electrical and optical excitation of silicon photo-diodes. The devices had areas of 8.2 mm2 and reverse bias saturation currents of the order of 10-10 A. Their current-voltage (I-V) response was exploited experimentally both in the dark and under various illumination levels. The quoted values for the saturation current, the ideality factor, the series resistance and the reverse-bias photocurrent are investigated for the simulation of the I-V curves via the quasi-equilibrium model. In addition, the measured I-V data have been further analysed to estimate the produced photocurrent as a function of the applied bias (forward or reverse) under given illumination levels. Comparisons between the simulated curves and the experimental data allowed a detailed photocurrent modelling validation. The proposed approach could be useful towards studying other parameters of optically activated <span class="hlt">p-n</span> junctions such as: the bias dependence of the minority carrier diffusion lengths and/or the generated rates of electron-hole pairs (EHP).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApPhL.108i3502T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApPhL.108i3502T"><span id="translatedtitle">Atomistic nature in band-to-band tunneling in two-dimensional silicon <span class="hlt">pn</span> tunnel diodes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tabe, Michiharu; Tan, Hoang Nhat; Mizuno, Takeshi; Muruganathan, Manoharan; Anh, Le The; Mizuta, Hiroshi; Nuryadi, Ratno; Moraru, Daniel</p> <p>2016-02-01</p> <p>We study low-temperature transport properties of two-dimensional (2D) Si tunnel diodes, or Si Esaki diodes, with a lateral layout. In ordinary Si Esaki diodes, interband tunneling current is severely limited because of the law of momentum conservation, while nanoscale Esaki diodes may behave differently due to the dopants in the narrow depletion region, by atomistic effects which release such current limitation. In thin-Si lateral highly doped <span class="hlt">pn</span> diodes, we find clear signatures of interband tunneling between 2D-subbands involving phonon assistance. More importantly, the tunneling current is sharply enhanced in a narrow voltage range by resonance via a pair of a donor- and an acceptor-atom in the <span class="hlt">pn</span> junction region. Such atomistic behavior is recognized as a general feature showing up only in nanoscale tunnel diodes. In particular, a donor-acceptor pair with deeper ground-state energies is likely to be responsible for such a sharply enhanced current peak, tunable by external biases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011aoel.confP..35D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011aoel.confP..35D"><span id="translatedtitle">The ARGOS wavefront sensor <span class="hlt">pn</span>CCD camera for an ELT: characteristics, limitations and applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>de Xivry, G. Orban; Ihle, S.; Ziegleder, J.; Barl, L.; Hartmann, R.; Rabien, S.; Soltau, H.; Strueder, L.</p> <p>2011-09-01</p> <p>From low-order to high-order AO, future wave front sensors on ELTs require large, fast, and low-noise detectors with high quantum efficiency and low dark current. While a detector for a high-order Shack-Hartmann WFS does not exist yet, the current CCD technology pushed to its limits already provides several solutions for the ELT AO detector requirements. One of these devices is the new WFS <span class="hlt">pn</span>CCD camera of ARGOS, the Ground-Layer Adaptive Optics system (GLAO) for LUCIFER at LBT. Indeed, with its 264x264 pixels, 48 mu m pixel size and 1kHz frame rate, this camera provides a technological solution to different needs of the AO systems for ELTs, such as low-order but as well possibly higher order correction using pyramid wavefront sensing. In this contribution, we present the newly developped WFS <span class="hlt">pn</span>CCD camera of ARGOS and how it fulfills future detector needs of AO on ELTs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014NatNa...9..257P&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014NatNa...9..257P&link_type=ABSTRACT"><span id="translatedtitle">Solar-energy conversion and light emission in an atomic monolayer <span class="hlt">p-n</span> diode</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pospischil, Andreas; Furchi, Marco M.; Mueller, Thomas</p> <p>2014-04-01</p> <p>The limitations of the bulk semiconductors currently used in electronic devices--rigidity, heavy weight and high costs--have recently shifted the research efforts to two-dimensional atomic crystals such as graphene and atomically thin transition-metal dichalcogenides. These materials have the potential to be produced at low cost and in large areas, while maintaining high material quality. These properties, as well as their flexibility, make two-dimensional atomic crystals attractive for applications such as solar cells or display panels. The basic building blocks of optoelectronic devices are <span class="hlt">p-n</span> junction diodes, but they have not yet been demonstrated in a two-dimensional material. Here, we report a <span class="hlt">p-n</span> junction diode based on an electrostatically doped tungsten diselenide (WSe2) monolayer. We present applications as a photovoltaic solar cell, a photodiode and a light-emitting diode, and obtain light-power conversion and electroluminescence efficiencies of ~0.5% and ~0.1%, respectively. Given recent advances in the large-scale production of two-dimensional crystals, we expect them to profoundly impact future developments in solar, lighting and display technologies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008JAP...104a6109L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008JAP...104a6109L"><span id="translatedtitle">Temperature-dependent parameters of band anticrossing in InGa<span class="hlt">PN</span> alloys</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lin, K. I.; Wang, T. S.; Tsai, J. T.; Hwang, J. S.</p> <p>2008-07-01</p> <p>Temperature-dependent photoreflectance (PR) measurements are employed to characterize the conduction band structure of In0.54Ga0.46P1-yNy (y =0 and 0.02) grown on GaAs substrates. The band gap and the upper subband E+ transition are observed in InGa<span class="hlt">PN</span> as predicted by the band anticrossing (BAC) model. To investigate the energetic positions of the features in the PR spectra, a Kramers-Kronig analysis is proposed. Based on the PR data and the BAC model, we find that the energy EN of isolated nitrogen states shifts significantly to higher energies with decreasing temperature. Simultaneously, the interaction potential V between the nitrogen states and the unperturbed conduction band also rises to higher values. At 293 K, EN=2.054 eV and V =1.513 eV are determined. The thermal shifts of EN and V are dEN/dT ≈-0.43 meV/K and dV /dT≈-0.67 meV/K, respectively. The temperature-dependent EN level and interaction potential V are attributed to the lattice distortions, which can be affected by temperature-induced changes in deformation potential. This information is important for overall validity of the BAC model to dilute nitride InGa<span class="hlt">PN</span> alloys.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JPhCS.533a2037C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JPhCS.533a2037C"><span id="translatedtitle">Empirical <span class="hlt">p-n</span> interactions, the synchronized filling of Nilsson orbitals, and emergent collectivity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cakirli, R. B.</p> <p>2014-09-01</p> <p>The onset of collectivity and deformation, changes to the single particle energies and magic numbers and so on are strongly influenced by, for example, proton (p) and neutron (n) interactions inside atomic nuclei. Experimentally, using binding energies (or masses), one can extract an average <span class="hlt">p-n</span> interaction between the last two protons and the last two neutrons, called δVpn. We have studied δVpn values using calculations of spatial overlaps between p and n Nilsson orbitals, considering different deformations, for the Z= 50-82, N= 82-126 shells, and comparison of these theoretical results with experimental δVpn values. Our results show that enhanced valence <span class="hlt">p-n</span> interactions are closely correlated with the development of collectivity, shape changes, and the saturation of deformation in nuclei. We note that the difference of the Nilsson quantum numbers of the last filled Nilsson p and n orbitals, has a special relation, 0[110], in which they differ by only a single quantum in the z-direction, for those nuclei where δVpn is largest for each Z in medium mass and heavy nuclei. The synchronised filling of such orbital pairs correlates with the emergence of collectivity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997PSSAR.159..523P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997PSSAR.159..523P"><span id="translatedtitle">Effect of Local Nonradiative Recombination on Time-Resolved Electroluminescence of <span class="hlt">p-n</span> Junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ptashchenko, A. A.; Melkonyan, D. V.; Moroz, N. V.; Ptashchenko, F. A.</p> <p>1997-02-01</p> <p>The effect of locally introduced dislocations on time-resolved electroluminescence (EL) in GaAlAs, GaAsP and GaP <span class="hlt">p-n</span> structures is studied. The data indicate that the local nonradiative recombination results in non-exponential EL decay. A one-dimensional model of this effect, involving back-diffusion of injected electrons, their extraction into the n-region and local recombination at dislocations and the surface, is proposed. An analysis of EL decay, based on this model, enables to estimate the bulk lifetime of minority carriers and some parameters of local nonradiative recombination. Der Einfluß örtlich eingeführter Dislokationen auf den Zeitverlauf der Elektrolumineszenz (EL) in GaAlAs, GaAsP und GaP <span class="hlt">p-n</span> Strukturen wurde studiert. Die experimentellen Daten zeigen, daß die lokale strahlungslose Rekombination zu einem nichtexponentiellen EL-Abfall führt. Ein eindimensionales Modell dieser Erscheinung, das die Rückdiffusion der injizierten Elektronen, ihre Extraktion in das n-Gebiet und lokale Rekombination an Dislokationen und der Oberfläche berücksichtigt, wird vorgeschlagen. Eine Analyse des EL-Abfalles auf Grund dieses Modells erlaubt, die Volumen-Lebensdauer von Minoritätsträgern und einige Parameter der lokalen strahlungslosen Rekombination abzuschätzen.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26090791','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26090791"><span id="translatedtitle">Lateral graphene <span class="hlt">p-n</span> junctions formed by the graphene/MoS₂ hybrid interface.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Meng, Jie; Song, Hua-Ding; Li, Cai-Zhen; Jin, Yibo; Tang, Lei; Liu, Dameng; Liao, Zhi-Min; Xiu, Faxian; Yu, Da-Peng</p> <p>2015-07-21</p> <p>Graphene/two-dimensional (2D) semiconductor heterostructures have been demonstrated to possess many advantages for electronic and optoelectronic devices. However, there are few reports about the utilization of a 2D semiconductor monolayer to tune the properties of graphene. Here, we report the fabrication and characterization of graphene <span class="hlt">p-n</span> junctions based on graphene/MoS2 hybrid interfaces. Monolayered graphene across the monolayered MoS2 boundary is divided into n-type regions on the MoS2 and p-type regions on the SiO2 substrate. Such van der Waals heterostructure based graphene <span class="hlt">p-n</span> junctions show good photoelectric properties. The photocurrent modulation of such devices by a single back gate is also demonstrated for the first time, which shows that the graphene on and off MoS2 regions have different responses to the gate voltage. Our results suggest that the atomic thin hybrid structure can remarkably extend the device applications. PMID:26090791</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Nanos...718537H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Nanos...718537H"><span id="translatedtitle">Anisotropic photocurrent response at black phosphorus-MoS2 <span class="hlt">p-n</span> heterojunctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hong, Tu; Chamlagain, Bhim; Wang, Tianjiao; Chuang, Hsun-Jen; Zhou, Zhixian; Xu, Ya-Qiong</p> <p>2015-11-01</p> <p>We investigate the photocurrent generation mechanisms at a vertical <span class="hlt">p-n</span> heterojunction between black phosphorus (BP) and molybdenum disulfide (MoS2) flakes through polarization-, wavelength-, and gate-dependent scanning photocurrent measurements. When incident photon energy is above the direct band gap of MoS2, the photocurrent response demonstrates a competitive effect between MoS2 and BP in the junction region. In contrast, if the incident photon energy is below the band gap of MoS2 but above the band gap of BP, the photocurrent response at the <span class="hlt">p-n</span> junction exhibits the same polarization dependence as that at the BP-metal junction, which is nearly parallel to the MoS2 channel. This result indicates that the photocurrent signals at the MoS2-BP junction primarily result from the direct band gap transition in BP. These fundamental studies shed light on the knowledge of photocurrent generation mechanisms in vertical 2D semiconductor heterojunctions, offering a new way of engineering future two-dimensional materials based optoelectronic devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25302489','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25302489"><span id="translatedtitle"><span class="hlt">p-n</span> Heterojunction of doped graphene films obtained by pyrolysis of biomass precursors.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Latorre-Sánchez, Marcos; Primo, Ana; Atienzar, Pedro; Forneli, Amparo; García, Hermenegildo</p> <p>2015-02-25</p> <p>Nitrogen-doped graphene [(N)G] obtained by pyrolysis at 900 °C of nanometric chitosan films exhibits a Hall effect characteristic of n-type semiconductors. In contrast, boron-doped graphene [(B)G] obtained by pyrolysis of borate ester of alginate behaves as a p-type semiconductor based also on the Hall effect. A <span class="hlt">p-n</span> heterojunction of (B)G-(N)G films is built by stepwise coating of a quartz plate using a mask. The heterojunction is created by the partial overlapping of the (B)G-(N)G films. Upon irradiation with a xenon lamp of aqueous solutions of H(2) PtCl(6) and MnCl(2) in contact with the heterojunction, preferential electron migration from (B)G to (N)G with preferential location of positive holes on (B)G is established by observation in scanning electron microscopy of the formation of Pt nanoparticles (NP) on (N)G and MnO(2) NP on (B)G. The benefits of the heterojunction with respect to the devices having one individual component as a consequence of the electron migration through the <span class="hlt">p-n</span> heterojunction are illustrated by measuring the photocurrent in the (B)G-(N)G heterojunction (180% current enhancement with respect to the dark current) and compared it to the photocurrent of the individual (B)G (15% enhancement) and (N)G (55% enhancement) components. PMID:25302489</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..MARJ28005H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..MARJ28005H"><span id="translatedtitle">Extremely large, gate tunable spin Hall angle in 3D Topological Insulator <span class="hlt">pn</span> junction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Habib, K. M. Masum; Sajjad, Redwan; Ghosh, Avik</p> <p>2015-03-01</p> <p>The band structure of the surface states of a three dimensional Topological Insulator (3D TI) is similar to that of graphene featuring massless Dirac Fermions. We show that due to this similarity, the chiral tunneling of electron in a graphene <span class="hlt">pn</span> junction also appears in 3D TI. Electrons with very small incident angle (modes) are allowed to transmit through a TI <span class="hlt">pn</span> junction (TIPNJ) due to the chiral tunneling. The rest of the electrons are reflected. As a result, the charge current in a TIPNJ is suppressed. Due to the spin momentum locking, all the small angle modes are spin-down states. Therefore, the transmitted end of the TIPNJ becomes highly spin polarized. On the other hand, the spin of the reflected electron is flipped due to spin momentum locking. This enhances the spin current at the injection end. Thus, the interplay between the chiral tunneling and spin momentum locking reduces the charge current but enhances the spin current at the same time, leading to an extremely large (~20) spin Hall angle. Since the chiral tunneling can be controlled by an external electric field, the spin Hall angle is gate tunable. The spin current generated by a TIPNJ can be used for energy-efficient switching of nanoscaled ferromagnets, which is an essential part of spintronic devices. This work is supported by the NRI INDEX center.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhRvB..86c5429C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhRvB..86c5429C"><span id="translatedtitle">Current oscillation of snake states in graphene <span class="hlt">p-n</span> junction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Jiang-chai; Xie, X. C.; Sun, Qing-feng</p> <p>2012-07-01</p> <p>Snake states in a six-terminal graphene <span class="hlt">p-n</span> junction are investigated under a perpendicular magnetic field. The current oscillation with varying magnetic field appears due to the presence of snake states at the <span class="hlt">p-n</span> interface. At a fixed magnetic field, the periodic properties of currents with respect to the geometric structures, such as the graphene ribbon width and the location of the incident terminal, are also shown. We extract the values of the width and the location corresponding to the maximums of the current and plot them versus their sequence number. They form a straight line, which shows that the oscillation is periodic. The periods decrease with increasing magnetic field. The order of magnitude of periods and their tendencies with varying a magnetic field are consistent with those predicted from semiclassical motions. Finally, for a smooth potential, the snake states still survive and the oscillation phase and the oscillation period with respect to the location of the incident terminal are almost unchanged, but the period with respect to the width of the ribbon is reduced.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005SPIE.5757..594H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005SPIE.5757..594H"><span id="translatedtitle">Virtual and flexible digital signal processing system based on software <span class="hlt">Pn</span>P and component works</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>He, Tao; Wu, Qinghua; Zhong, Fei; Li, Wei</p> <p>2005-05-01</p> <p>An idea about software <span class="hlt">Pn</span>P (Plug & Play) is put forward according to the hardware <span class="hlt">Pn</span>P. And base on this idea, a virtual flexible digital signal processing system (FVDSPS) is carried out. FVDSPS is composed of a main control center, many sub-function modules and other hardware I/O modules. Main control center sends out commands to sub-function modules, and manages running orders, parameters and results of sub-functions. The software kernel of FVDSPS is DSP (Digital Signal Processing) module, which communicates with the main control center through some protocols, accept commands or send requirements. The data sharing and exchanging between the main control center and the DSP modules are carried out and managed by the files system of the Windows Operation System through the effective communication. FVDSPS real orients objects, orients engineers and orients engineering problems. With FVDSPS, users can freely plug and play, and fast reconfigure a signal process system according to engineering problems without programming. What you see is what you get. Thus, an engineer can orient engineering problems directly, pay more attention to engineering problems, and promote the flexibility, reliability and veracity of testing system. Because FVDSPS orients TCP/IP protocol, through Internet, testing engineers, technology experts can be connected freely without space. Engineering problems can be resolved fast and effectively. FVDSPS can be used in many fields such as instruments and meter, fault diagnosis, device maintenance and quality control.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Nanos...8.9592H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Nanos...8.9592H"><span id="translatedtitle">Flexible infrared detectors based on <span class="hlt">p-n</span> junctions of multi-walled carbon nanotubes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huang, Zhenlong; Gao, Min; Yan, Zhuocheng; Pan, Taisong; Liao, Feiyi; Lin, Yuan</p> <p>2016-05-01</p> <p>Different types of multi-walled carbon nanotubes (CNTs), synthesized by chemical vapor deposition, are used to fabricate infrared (IR) detectors on flexible substrates based on CNT <span class="hlt">p-n</span> junctions. It is found that this kind of detector is sensitive to infrared signals with a power density as low as 90 μW mm-2 even at room temperature. Besides, unlike other devices, the detector with this unique structure can be bent for 100 cycles without any damage and its functionality does not degenerate once it recovers to the initial state. The results give a good reference for developing efficient, low-cost, and flexible IR detectors.Different types of multi-walled carbon nanotubes (CNTs), synthesized by chemical vapor deposition, are used to fabricate infrared (IR) detectors on flexible substrates based on CNT <span class="hlt">p-n</span> junctions. It is found that this kind of detector is sensitive to infrared signals with a power density as low as 90 μW mm-2 even at room temperature. Besides, unlike other devices, the detector with this unique structure can be bent for 100 cycles without any damage and its functionality does not degenerate once it recovers to the initial state. The results give a good reference for developing efficient, low-cost, and flexible IR detectors. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr08791k</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015JAP...118k4506D&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015JAP...118k4506D&link_type=ABSTRACT"><span id="translatedtitle">Opto-electronic modeling of light emission from avalanche-mode silicon <span class="hlt">p+n</span> junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dutta, Satadal; Hueting, Raymond J. E.; Annema, Anne-Johan; Qi, Lin; Nanver, Lis K.; Schmitz, Jurriaan</p> <p>2015-09-01</p> <p>This work presents the modeling of light emission from silicon based <span class="hlt">p+n</span> junctions operating in avalanche breakdown. We revisit the photon emission process under the influence of relatively high electric fields in a reverse biased junction ( > 10 5 V/cm). The photon emission rate is described as a function of the electron temperature T e , which is computed from the spatial distribution of the electric field. The light emission spectra lie around the visible spectral range ( λ ˜ 300-850 nm), where the peak wavelength and the optical intensity are both doping level dependent. It is theoretically derived that a specific minimum geometrical width ( ˜ 170 nm) of the active region of avalanche is required, corresponding to a breakdown voltage of ˜5 V, below which the rate of photon emission in the desired spectrum drops. The derived model is validated using experimental data obtained from ultra-shallow <span class="hlt">p+n</span> junctions with low absorption through a nm-thin p+ region and surface coverage of solely 3 nm of pure boron. We observe a peak in the emission spectra near 580 nm and 650 nm for diodes with breakdown voltages 7 V and 14 V, respectively, consistent with our model.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRB..120.7558Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRB..120.7558Z"><span id="translatedtitle"><span class="hlt">Pn</span> wave geometrical spreading and attenuation in Northeast China and the Korean Peninsula constrained by observations from North Korean nuclear explosions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Lian-Feng; Xie, Xiao-Bi; Tian, Bao-Feng; Chen, Qi-Fu; Hao, Tian-Yao; Yao, Zhen-Xing</p> <p>2015-11-01</p> <p>We investigate the geometric spreading and attenuation of seismic <span class="hlt">Pn</span> waves in Northeast China and the Korean Peninsula. A high-quality broadband <span class="hlt">Pn</span> wave data set generated by North Korean nuclear tests is used to constrain the parameters of a frequency-dependent log-quadratic geometric spreading function and a power law <span class="hlt">Pn</span> Q model. The geometric spreading function and apparent <span class="hlt">Pn</span> wave Q are obtained for Northeast China and the Korean Peninsula between 2.0 and 10.0 Hz. Using the two-station amplitude ratios of the <span class="hlt">Pn</span> spectra and correcting them with the known spreading function, we remove the contributions of the source and crust from the apparent <span class="hlt">Pn</span> Q and retrieve the P wave attenuation information along the pure upper mantle path. We then use both <span class="hlt">Pn</span> amplitudes and amplitude ratios in a tomographic approach to obtain the upper mantle P wave attenuation in the studied area. The <span class="hlt">Pn</span> wave spectra observed in China are compared with those recorded in Japan, and the result reveals that the high-frequency <span class="hlt">Pn</span> signal across the oceanic path attenuated faster compared with those through the continental path.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015OptCo.343...51X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015OptCo.343...51X"><span id="translatedtitle">Microdisk resonator assisted all-optical switching with improved speed using a reverse-biased <span class="hlt">p-n</span> diode</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xie, Jingya; Zhou, Linjie; Li, Xinwan; Chen, Jianping</p> <p>2015-05-01</p> <p>We present a compact and power efficient all-optical switching using a silicon microdisk resonator integrated with a <span class="hlt">p-n</span> junction. We study the dependence of free-carrier lifetime, one of the most critical parameters to determine the switching speed, on reverse bias, optical intensity, and <span class="hlt">p-n</span> junction position and dimension. Our experiments reveal that the carrier lifetime decreases with the increasing reverse bias, consistent with the theoretical results. The all-optical switching of a 211-1 non-return-to-zero pseudo-random binary sequence (PRBS) signal at a data rate of 10 Gbits/s is demonstrated with <span class="hlt">p-n</span> junction reversely biased at -15 V and the pump power being 5.96 dBm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JAP...114o3101H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JAP...114o3101H"><span id="translatedtitle">Theory of open-circuit voltage and the driving force of charge separation in <span class="hlt">pn</span>-junction solar cells</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hara, Kosuke O.; Usami, Noritaka</p> <p>2013-10-01</p> <p>We have derived the formula to calculate the open-circuit voltage in a <span class="hlt">pn</span>-junction solar cell from carrier densities by considering the driving force of charge separation without using the equation for current. The excess amount of chemical potential of charge carriers is proposed as the origin of the driving force of charge separation, and the voltage formula is derived from the gradient of excess chemical potential. The calculated voltage is shown to agree with the result of a rigorous device simulation for symmetrical <span class="hlt">pn</span>-homojunction devices with band gaps of 0.6-1.8 eV and majority-carrier densities of 1015-1019 cm-3. The developed formula is, therefore, valid for the <span class="hlt">pn</span>-homojunction devices, indicating that the driving force of charge separation stems from the excess chemical potential.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JAP...110g4308B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JAP...110g4308B"><span id="translatedtitle">Imaging the formation of a <span class="hlt">p-n</span> junction in a suspended carbon nanotube with scanning photocurrent microscopy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Buchs, Gilles; Barkelid, Maria; Bagiante, Salvatore; Steele, Gary A.; Zwiller, Val</p> <p>2011-10-01</p> <p>We use scanning photocurrent microscopy (SPCM) to investigate individual suspended semiconducting carbon nanotube devices where the potential profile is engineered by means of local gates. In situ tunable <span class="hlt">p-n</span> junctions can be generated at any position along the nanotube axis. Combining SPCM with transport measurements allows a detailed microscopic study of the evolution of the band profiles as a function of the gates voltage. Here we study the emergence of a <span class="hlt">p-n</span> and a n-p junctions out of a n-type transistor channel using two local gates. In both cases the I - V curves recorded for gate configurations corresponding to the formation of the <span class="hlt">p-n</span> or n-p junction in the SPCM measurements reveal a clear transition from resistive to rectification regimes. The rectification curves can be fitted well to the Shockley diode model with a series resistor and reveal a clear ideal diode behavior.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22285093','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22285093"><span id="translatedtitle">Improved photocatalytic activity of single crystal ZnO nanorod derived from highly effective <span class="hlt">P/N</span> heterojunction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Yan, Xiaoyan; Gong, Changwei; Wang, Jian; Liang, Liping; Zhao, Li; Zhang, Mingang; Chai, Yuesheng</p> <p>2013-10-15</p> <p>Graphical abstract: Schematic showing on photocatalytic degradation 2,4-DCP of ZnO NRs/BDD heterojunction. - Highlights: • Single-crystal ZnO nanorods based <span class="hlt">P/N</span> heterojunction has been synthesized. • Vertical growth ZnO NRs on BDD can effectively photocatalytic decompose 2,4-DCP. • The rate constant of photocatalysis can be enhanced due to <span class="hlt">P/N</span> heterojunction. - Abstract: Highly effective single-crystal ZnO nanorods based <span class="hlt">P/N</span> heterojunction has been synthesized by a controllable crystal seed-induced hydrothermal vertical growth method, which facilitates the separation of the photogenerated electrons and holes due to its endogenous space charge region and suitable band structure. Therefore, photocatalytic activity for degradation of the toxic pollutants is markedly enhanced.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhLA..379.1732Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhLA..379.1732Y"><span id="translatedtitle">Valley detection using a graphene gradual <span class="hlt">pn</span> junction with spin-orbit coupling: An analytical conductance calculation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Mou; Wang, Rui-Qiang; Bai, Yan-Kui</p> <p>2015-09-01</p> <p>Graphene <span class="hlt">pn</span> junction is the brick to build up variety of graphene nano-structures. The analytical formula of the conductance of graphene gradual <span class="hlt">pn</span> junctions in the whole bipolar region has been absent up to now. In this paper, we analytically calculated that <span class="hlt">pn</span> conductance with the spin-orbit coupling and stagger potential taken into account. Our analytical expression indicates that the energy gap causes the conductance to drop a constant value with respect to that without gap in a certain parameter region, and manifests that the curve of the conductance versus the stagger potential consists of two Gaussian peaks - one valley contributes one peak. The latter feature allows one to detect the valley polarization without using double-interface resonant devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6299087','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/6299087"><span id="translatedtitle">Diffusion of dopant from optical coating and single step formation of <span class="hlt">pn</span> junction in silicon solar cell and coating thereon</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Yoldas, B. E.; Yoldas, L. A.</p> <p>1981-02-17</p> <p>The <span class="hlt">pn</span> juncture in a silicon chip and an oxide coating on its surface are simultaneously formed from clear solution derived from titanium alkoxides, water, alcohol, a suitable acid, and a P or N dopant compound by partial hydrolysis and polymerization. The solution is applied to the surface of a silicon chip. The chip is then heated which converts the solution to a solid oxide coating which meets the antireflective optical film requirements and induces the migration of the dopants into the chip, forming a <span class="hlt">pn</span> junction in the chip. The method also provides deep and uniform junction formation or diffusion without resulting in excessive carrier concentration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25078219','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25078219"><span id="translatedtitle">Enhanced near-infrared photodetection with avalanche gain in silicon microdisk resonators integrated with <span class="hlt">p-n</span> diodes.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhu, Haike; Zhou, Linjie; Yang, Rui; Li, Xinwan; Chen, Jianping</p> <p>2014-08-01</p> <p>We investigate the photocurrent generation by two-photon absorption effect in silicon microdisk resonators integrated with <span class="hlt">p-n</span> diodes. The photocurrent is quite dependent on the <span class="hlt">p-n</span> junction position with respect to the whispering gallery mode. Avalanche gain increases significantly when the bias exceeds -19  V, leading to considerable enhancement of photocurrent. At -22  V bias with on-chip optical power of 44.7 μW, the responsivity exceeds 1 A/W with an avalanche gain of 188 while the dark current is more than 50 times lower than the photocurrent. PMID:25078219</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016Nanos...813245W&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016Nanos...813245W&link_type=ABSTRACT"><span id="translatedtitle">Electrostatically tunable lateral MoTe2 <span class="hlt">p-n</span> junction for use in high-performance optoelectronics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Zhenxing; Wang, Feng; Yin, Lei; Huang, Yun; Xu, Kai; Wang, Fengmei; Zhan, Xueying; He, Jun</p> <p>2016-07-01</p> <p>Because of their ultimate thickness, layered structure and high flexibility, <span class="hlt">pn</span> junctions based on layered two-dimensional semiconductors have been attracting increasing attention recently. In this study, for the first time, we fabricated lateral <span class="hlt">pn</span> junctions (LPNJs) based on ultrathin MoTe2 by introducing two separated electrostatic back gates, and investigated their electronic and photovoltaic performance. <span class="hlt">Pn</span>, np, nn, and pp junctions can be easily realized by modulating the conductive channel type using gate voltages with different polarities. Strong rectification effects were observed in the <span class="hlt">pn</span> and np junctions and the rectification ratio reached ~5 × 104. Importantly, we find a unique phenomenon that the parameters for MoTe2 LPNJs experience abrupt changes during the transition from p to n or n to p. Furthermore, a high performance photovoltaic device with a filling factor of above 51% and electrical conversion efficiency (η) of around 0.5% is achieved. Our findings are of importance to comprehensively understand the electronic and optoelectronic properties of MoTe2 and may further open up novel electronic and optoelectronic device applications.Because of their ultimate thickness, layered structure and high flexibility, <span class="hlt">pn</span> junctions based on layered two-dimensional semiconductors have been attracting increasing attention recently. In this study, for the first time, we fabricated lateral <span class="hlt">pn</span> junctions (LPNJs) based on ultrathin MoTe2 by introducing two separated electrostatic back gates, and investigated their electronic and photovoltaic performance. <span class="hlt">Pn</span>, np, nn, and pp junctions can be easily realized by modulating the conductive channel type using gate voltages with different polarities. Strong rectification effects were observed in the <span class="hlt">pn</span> and np junctions and the rectification ratio reached ~5 × 104. Importantly, we find a unique phenomenon that the parameters for MoTe2 LPNJs experience abrupt changes during the transition from p to n or n to p. Furthermore</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015Nanos...715442V&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015Nanos...715442V&link_type=ABSTRACT"><span id="translatedtitle">Gate-tunable diode and photovoltaic effect in an organic-2D layered material <span class="hlt">p-n</span> junction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vélez, Saül; Ciudad, David; Island, Joshua; Buscema, Michele; Txoperena, Oihana; Parui, Subir; Steele, Gary A.; Casanova, Fèlix; van der Zant, Herre S. J.; Castellanos-Gomez, Andres; Hueso, Luis E.</p> <p>2015-09-01</p> <p>The semiconducting <span class="hlt">p-n</span> junction is a simple device structure with great relevance for electronic and optoelectronic applications. The successful integration of low-dimensional materials in electronic circuits has opened the way forward for producing gate-tunable <span class="hlt">p-n</span> junctions. In that context, we present here an organic (Cu-phthalocyanine)-2D layered material (MoS2) hybrid <span class="hlt">p-n</span> junction with both gate-tunable diode characteristics and photovoltaic effect. Our proof-of-principle devices show multifunctional properties with diode rectifying factors of up to 104, while under light exposure they exhibit photoresponse with a measured external quantum efficiency of ~11%. As for their photovoltaic properties, we found open circuit voltages of up to 0.6 V and optical-to-electrical power conversion efficiency of 0.7%. The extended catalogue of known organic semiconductors and two-dimensional materials offer the prospect for tailoring the properties and the performance of the resulting devices, making organic-2D <span class="hlt">p-n</span> junctions promising candidates for future technological applications.The semiconducting <span class="hlt">p-n</span> junction is a simple device structure with great relevance for electronic and optoelectronic applications. The successful integration of low-dimensional materials in electronic circuits has opened the way forward for producing gate-tunable <span class="hlt">p-n</span> junctions. In that context, we present here an organic (Cu-phthalocyanine)-2D layered material (MoS2) hybrid <span class="hlt">p-n</span> junction with both gate-tunable diode characteristics and photovoltaic effect. Our proof-of-principle devices show multifunctional properties with diode rectifying factors of up to 104, while under light exposure they exhibit photoresponse with a measured external quantum efficiency of ~11%. As for their photovoltaic properties, we found open circuit voltages of up to 0.6 V and optical-to-electrical power conversion efficiency of 0.7%. The extended catalogue of known organic semiconductors and two-dimensional materials</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016RaPC..125..205R&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016RaPC..125..205R&link_type=ABSTRACT"><span id="translatedtitle">Optimization of Silicon parameters as a betavoltaic battery: Comparison of Si <span class="hlt">p-n</span> and Ni/Si Schottky barrier</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rahmani, Faezeh; Khosravinia, Hossein</p> <p>2016-08-01</p> <p>Theoretical studies on the optimization of Silicon (Si) parameters as the base of betavoltaic battery have been presented using Monte Carlo simulations and the state equations in semiconductor to obtain maximum power. Si with active area of 1 cm2 has been considered in <span class="hlt">p-n</span> junction and Schottky barrier structure to collect the radiation induced-charge from 10 mCi cm-2 of Nickle-63 (63Ni) Source. The results show that the betavoltaic conversion efficiency in the Si <span class="hlt">p-n</span> structure is about 2.7 times higher than that in the Ni/Si Schottky barrier structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20020022205&hterms=Marten&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DMarten','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20020022205&hterms=Marten&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DMarten"><span id="translatedtitle">Atmospheric Fluorescence <span class="hlt">Yield</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Adams, James H., Jr.; Christl, M. J.; Fountain, W. F.; Gregory, J. C.; Martens, K.; Sokolsky, P.; Whitaker, Ann F. (Technical Monitor)</p> <p>2001-01-01</p> <p>Several existing and planned experiments estimate the energies of ultra-high energy cosmic rays from air showers using the atmospheric fluorescence from these showers. Accurate knowledge of the conversion from atmospheric fluorescence to energy loss by ionizing particles in the atmosphere is key to this technique. In this paper we discuss a small balloon-borne instrument to make the first in situ measurements versus altitude of the atmospheric fluorescence <span class="hlt">yield</span>. The instrument can also be used in the lab to investigate the dependence of the fluorescence <span class="hlt">yield</span> in air on temperature, pressure and the concentrations of other gases that present in the atmosphere. The results can be used to explore environmental effects on and improve the accuracy of cosmic ray energy measurements for existing ground-based experiments and future space-based experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19890003946','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19890003946"><span id="translatedtitle">Application of <span class="hlt">PN</span> and avalanche silicon photodiodes to low-level optical</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Eppeldauer, G.; Schaefer, A. R.</p> <p>1988-01-01</p> <p>New approaches to the discovery of other planetary systems require very sensitive and stable detection techniques in order to succeed. Two methods in particular, the astrometric and the photometric methods, require this. To begin understanding the problems and limitations of solid state detectors regarding this application, preliminary experiments were performed at the National Bureau of Standards and a low light level detector characterization facility was built. This facility is briefly described, and the results of tests conducted in it are outlined. A breadboard photometer that was used to obtain stellar brightness ratio precision data is described. The design principles of <span class="hlt">PN</span> and avalanche silicon photodiodes based on low light level measuring circuits are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014snam.conf04101V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014snam.conf04101V"><span id="translatedtitle">Domain Decomposition <span class="hlt">PN</span> Solutions to the 3D Transport Benchmark over a Range in Parameter Space</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Van Criekingen, S.</p> <p>2014-06-01</p> <p>The objectives of this contribution are twofold. First, the Domain Decomposition (DD) method used in the parafish parallel transport solver is re-interpreted as a Generalized Schwarz Splitting as defined by Tang [SIAM J Sci Stat Comput, vol.13 (2), pp. 573-595, 1992]. Second, parafish provides spherical harmonic (i.e., <span class="hlt">PN</span>) solutions to the NEA benchmark suite for 3D transport methods and codes over a range in parameter space. To the best of the author's knowledge, these are the first spherical harmonic solutions provided for this demanding benchmark suite. They have been obtained using 512 CPU cores of the JuRoPa machine installed at the Jülich Computing Center (Germany).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26371673','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26371673"><span id="translatedtitle">Spin-Based Mach-Zehnder Interferometry in Topological Insulator <span class="hlt">p-n</span> Junctions.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ilan, Roni; de Juan, Fernando; Moore, Joel E</p> <p>2015-08-28</p> <p>Transport in three-dimensional topological insulators relies on the existence of a spin-momentum locked surface state that encloses the insulating bulk. In this work we show how, in a topological insulator <span class="hlt">p-n</span> junction, a magnetic field turns this surface state into an electronic Mach-Zehnder interferometer. Transmission of the junction can be tuned from zero to unity, resulting in virtually perfect visibility of the interference pattern, and the reflected and transmitted currents carry opposite spin polarization so that the junction also acts as a spin filter. Our setup therefore realizes a novel and highly tunable spintronic device where the effects of spin-momentum locking in topological insulator surface states can be probed directly in a transport experiment. PMID:26371673</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27254390','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27254390"><span id="translatedtitle">Direct Measurement of the Electrical Abruptness of a Nanowire <span class="hlt">p-n</span> Junction.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Darbandi, Ali; McNeil, James C; Akhtari-Zavareh, Azadeh; Watkins, Simon P; Kavanagh, Karen L</p> <p>2016-07-13</p> <p>Electrostatic potential maps of GaAs nanowire, <span class="hlt">p-n</span> junctions have been measured via off-axis electron holography and compared to results from in situ electrical probing, and secondary electron emission microscopy using scanning electron microscopy. The built-in potential and depletion length of an axial junction was found to be 1.5 ± 0.1 V and 74 ± 9 nm, respectively, to be compared with 1.53 V and 64 nm of an abrupt junction of the same end point carrier concentrations. Associated with the switch from Te to Zn dopant precursor was a reduction in GaAs nanowire diameter 3 ± 1 nm that occurred prior to the junction center (n = p) and was followed by a rapid increase in Zn doping. The delay in Zn incorporation is attributed to the time required for Zn to equilibrate within the Au catalyst. PMID:27254390</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MARK17001C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MARK17001C"><span id="translatedtitle">Gate-tunable electron focusing across graphene <span class="hlt">p-n</span> junction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Shaowen; Han, Zheng; Wang, Lei; Dean, Cory; Hone, James</p> <p></p> <p>Electrons moving across a ballistic semiconductor junction experience a change in trajectory described by an electronic version of Snell's law. In the case of a barrier separating regions of n and ptype carriers, negative refraction is expected, which theoretically leads to a Veselago type of electron focusing. Being a ballistic bipolar 2D system, hexagonal Boron Nitride-encapsulated graphene is expected to be a model a system to realize this effect, however, robust demonstration of veselago lensing has remained limited. We describe novel methods to fabricate high quality graphene <span class="hlt">p-n</span> junctions with atomically sharp boundaries. Using a magnetic focusing measurement scheme, we demonstrate unambiguous signatures of negative refraction in these devices. Our observations are in good agreement with simulations and shed light on future application for electronic optics in ballistic graphene.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22102315','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22102315"><span id="translatedtitle">Assessing thermal damage in silicon <span class="hlt">PN</span>-junctions using Raman thermometry</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Beechem, Thomas E.; Serrano, Justin R.; McDonald, Anthony; Mani, Seethambal</p> <p>2013-03-28</p> <p>Laser machining is frequently utilized in the manufacture of photovoltaics. A natural by-product of these fabrication processes, heat, not only serves as a means of material removal but also modifies the material in an extended region beyond that ideally intended for alteration. This modified region, termed the heat affected zone, is detrimental to performance and should therefore be minimized. While undoubtedly thermal in origin, it is unclear exactly how the thermal environment during laser machining correlates to changes in the <span class="hlt">PN</span>-junction that reduce performance. In response, we combine in-situ Raman based thermometry measurements with post-event failure analysis to identify the physical mechanisms damaging the junction during laser machining. From this approach, damage is shown to initiate prior to melting and be driven primarily by the diffusion of dopants for fluences that do not induce ablation. Additionally, comparatively small regions of damage are shown to have a large impact on operation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6479182','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6479182"><span id="translatedtitle">MIS and <span class="hlt">PN</span> junction solar cells on thin-film polycrystalline silicon</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ariotedjo, A.; Emery, K.; Cheek, G.; Pierce, P.; Surek, T.</p> <p>1981-05-01</p> <p>The Photovoltaic Advanced Silicon (PVAS) Branch at the Solar Energy Research Institute (SERI) has initiated a comparative study to assess the potential of MIS-type solar cells for low-cost terrestrial photovoltaic systems in terms of performance, stability, and cost-effectiveness. Several types of MIS and SIS solar cells are included in the matrix study currently underway. This approach compares the results of MIS and <span class="hlt">p/n</span> junction solar cells on essentially identical thin-film polycrystalline silicon materials. All cell measurements and characterizations are performed using uniform testing procedures developed in the Photovoltaic Measurements and Evaluation (PV M and E) Laboratory at SERI. Some preliminary data on the different cell structures on thin-film epitaxial silicon on metallurgical-grade substrates are presented here.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6898223','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/6898223"><span id="translatedtitle">Study of novel chemical surface passivation techniques on GaAs <span class="hlt">pn</span> junction solar cells</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Mauk, M.G.; Xu, S.; Arent, D.J.; Mertens, R.P.; Borghs, G.</p> <p>1989-01-16</p> <p>Novel methods of GaAs surface passivation are investigated. Passivation is acheived by simple chemical treatments using aqueous solutions of Na/sub 2/S, KOH, RuCl/sub 3/, and K/sub 2/Se. GaAs <span class="hlt">pn</span> homojunction solar cells are used to evaluate the effectiveness of these passivation techniques. A significant reduction in minority-carrier surface recombination velocity is demonstrated. In the best case, the surface recombination velocity decreased from 5 x 10/sup 6/ cm/s (untreated surface) to 10/sup 3/ cm/s. In addition, we observe improvements in solar cell photogenerated current, short wavelength spectral response, open-circuit voltage, and junction ''dark'' current.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19880047073&hterms=pn+junction+solar+cell&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dpn%2Bjunction%2Bsolar%2Bcell','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19880047073&hterms=pn+junction+solar+cell&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dpn%2Bjunction%2Bsolar%2Bcell"><span id="translatedtitle">A V-grooved AlGaAs/GaAs passivated <span class="hlt">pn</span> junction</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bailey, S. G.; Leon, R. P.; Arrison, A.</p> <p>1987-01-01</p> <p>A passivated, V-grooved GaAs solar cell offers important advantages in terms of improved optical coupling, higher short-circuit current, and increased tolerance to particle radiation when compared to the planar cell configuration. An AlGaAs epilayer has been deposited on a p-type GaAs epilayer grown on an n-type V-grooved GaAs surface using MOCVD. A wet chemical etching process was used to produce a V-pattern with a 7.0-micron periodicity. Reflectivity measurements substantiate the expected decrease in solar reflectance. Scanning electron microscopy techniques were used to confirm the presence of the AlGaAs layer and verify the existence of a <span class="hlt">pn</span> junction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/191134','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/191134"><span id="translatedtitle">A simple model of a graded band-gap <span class="hlt">pn</span>-heterojunction cell</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sinkkonen, J.</p> <p>1994-12-31</p> <p>Alloy semiconductors with spatially varying composition represent a very general class of semiconductors having position dependent material parameters. The current-voltage characteristics of a <span class="hlt">pn</span>-junction is constructed with the aid of drift-diffusion theory. The one dimensional analysis is based on the integration of the differential equations for the quasi-Fermi levels. The result is a formally exact, simple equation for the current density, which can be easily used for practical calculations. The treatment introduces a spatial collection efficiency function which gives the probability that a carrier generated at a given point in the cell will contribute to the current. The collection efficiency is closely related to the spectral response function. The results predicted by the model are compared to those obtained from the full numerical simulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19870018108','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19870018108"><span id="translatedtitle">A V-grooved AlGaAs/GaAs passivated <span class="hlt">PN</span> junction</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bailey, Sheila G.; Leon, Rosa P.; Arrison, Anne</p> <p>1987-01-01</p> <p>A passivated, V-grooved GaAs solar cell offers important advantages in terms of improved optical coupling, higher short circuit current, and increased tolerance to particle radiation when compared to the planar cell configuration. An AlGaAs epilayer has been deposited on a p-type GaAs epilayer grown on an n-type V-grooved GaAs surface using MOCVD. A wet chemical etching process was used to produce a V-pattern with a 7.0 micron periodicity. Reflectivity measurements substantiate the expected decrease in solar reflectance. Scanning electron microscopy techniques were used to confirm the presence of the AlGaAs layer and verify the existence of a <span class="hlt">pn</span> junction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6050074','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/6050074"><span id="translatedtitle">V-grooved AlGaAs/GaAs passivated <span class="hlt">PN</span> junction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bailey, S.G.; Leon, R.P.; Arrison, A.</p> <p>1987-05-01</p> <p>A passivated, V-grooved GaAs solar cell offers important advantages in terms of improved optical coupling, higher short circuit current, and increased tolerance to particle radiation when compared to the planar cell configuration. An AlGaAs epilayer has been deposited on a p-type GaAs epilayer grown on an n-type V-grooved GaAs surface using MOCVD. A wet chemical etching process was used to produce a V-pattern with a 7.0 micron periodicity. Reflectivity measurements substantiate the expected decrease in solar reflectance. Scanning electron microscopy techniques were used to confirm the presence of the AlGaAs layer and verify the existence of a <span class="hlt">pn</span> junction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/7082044','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/7082044"><span id="translatedtitle">Method utilizing laser-processing for the growth of epitaxial <span class="hlt">p-n</span> junctions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Young, R.T.; Narayan, J.; Wood, R.F.</p> <p>1979-11-23</p> <p>This invention is a new method for the formation of epitaxial <span class="hlt">p-n</span> junctions in silicon. The method is relatively simple, rapid, and reliable. It produces doped epitaxial layers which are of well-controlled thickness and whose electrical properties are satisfactory. An illustrative form of the method comprises co-depositing a selected dopant and amorphous silicon on a crystalline silicon substrate to form a doped layer of amorphous silicon thereon. This layer then is irradiated with at least one laser pulse to generate a melt front which moves through the layer, into the silicon body to a depth effecting melting of virginal silicon, and back to the surface of the layer. The method may be conducted with dopants (e.g., boron and phosphorus) whose distribution coefficients approximate unity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940006913','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940006913"><span id="translatedtitle">Electrochemical characterization of <span class="hlt">p(+)n</span> and n(+)p diffused InP structures</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wilt, David M.; Faur, Maria; Faur, Mircea; Goradia, M.; Vargas-Aburto, Carlos</p> <p>1993-01-01</p> <p>The relatively well documented and widely used electrolytes for characterization and processing of Si and GaAs-related materials and structures by electrochemical methods are of little or no use with InP because the electrolytes presently used either dissolve the surface preferentially at the defect areas or form residual oxides and introduce a large density of surface states. Using an electrolyte which was newly developed for anodic dissolution of InP, and was named the 'FAP' electrolyte, accurate characterization of InP related structures including nature and density of surface states, defect density, and net majority carrier concentration, all as functions of depth was performed. A step-by-step optimization of n(+)p and <span class="hlt">p(+)n</span> InP structures made by thermal diffusion was done using the electrochemical techniques, and resulted in high performance homojunction InP structures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009IJMPE..18..309L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009IJMPE..18..309L"><span id="translatedtitle">TETRAQUARK X(udbar sbar s) PRODUCTION IN <span class="hlt">pn</span> → ΛΛX</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Xiao-Hai; Zhao, Qiang</p> <p></p> <p>We propose to search for a tetraquark candidate X(udbar sbar s) in <span class="hlt">pn</span> -> Λ Λ X(udbar sbar s) -> Λ Λ K^ + K0 or ΛΛKK*. The existence of tetraquark state X(udbar sbar s) was predicted in the literature due to specific diquark effective degrees of freedom inside hadrons. In order to understand the underlying dynamics for exotic hadrons, a search for the tetraquark X(udbar sbar s) is strongly recommended. We make an estimate of the production rate of X(udbar sbar s) in an effective lagrangian theory. The proposed reaction involves two Λ production, of which the narrow widths make it a great advantage in the analysis of the final state missing mass spectrum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22486187','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22486187"><span id="translatedtitle">High breakdown single-crystal GaN <span class="hlt">p-n</span> diodes by molecular beam epitaxy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Qi, Meng; Zhao, Yuning; Yan, Xiaodong; Li, Guowang; Verma, Jai; Fay, Patrick; Nomoto, Kazuki; Zhu, Mingda; Hu, Zongyang; Protasenko, Vladimir; Song, Bo; Xing, Huili Grace; Jena, Debdeep; Bader, Samuel</p> <p>2015-12-07</p> <p>Molecular beam epitaxy grown GaN <span class="hlt">p-n</span> vertical diodes are demonstrated on single-crystal GaN substrates. A low leakage current <3 nA/cm{sup 2} is obtained with reverse bias voltage up to −20 V. With a 400 nm thick n-drift region, an on-resistance of 0.23 mΩ cm{sup 2} is achieved, with a breakdown voltage corresponding to a peak electric field of ∼3.1 MV/cm in GaN. Single-crystal GaN substrates with very low dislocation densities enable the low leakage current and the high breakdown field in the diodes, showing significant potential for MBE growth to attain near-intrinsic performance when the density of dislocations is low.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JaJAP..51i0116M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JaJAP..51i0116M"><span id="translatedtitle">Device Design of Diamond Schottky-<span class="hlt">pn</span> Diode for Low-Loss Power Electronics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Makino, Toshiharu; Kato, Hiromitsu; Takeuchi, Daisuke; Ogura, Masahiko; Okushi, Hideyo; Yamasaki, Satoshi</p> <p>2012-09-01</p> <p>The device parameters of a novel diamond diode, namely, a Schottky-<span class="hlt">pn</span> diode (SPND), are analyzed to realize a fast switching time, a low on-resistance, and a high blocking voltage simultaneously. The SPND is composed of an n-type active layer sandwiched between a highly doped p+-type layer and a Schottky metal. The key structure is the fully depleted n-type layer. From the simulations of the energy band diagram based on the key structure of the SPND using Poisson's equations, it is concluded that the low donor density in the n-type layer and the high acceptor density in the p+-type layer are key points for the high-performance SPND.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/19113298','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/19113298"><span id="translatedtitle">Current induced decomposition of Abrikosov vortices in <span class="hlt">p-n</span> layered superconductors and heterostructures.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rakhmanov, A L; Savel'ev, Sergey; Kusmartsev, F V</p> <p>2008-11-01</p> <p>We describe the decomposition of Abrikosov vortices into decoupled pancake vortices in superconductors having both electron and hole charge carriers. We estimate the critical current of such a decomposition, at which a superconducting-normal state transition occurs, and find that it is very sensitive to the magnetic field and temperature. The effect can be observed in recently synthesized self-doped high-Tc layered superconductors with electrons and holes coexisting in different Cu-O planes and in artificial <span class="hlt">p-n</span> superconductor heterostructures. The sensitivity of the critical current to a magnetic field may be used for sensors and detectors of a magnetic field, which can be built up from the superconductor heterostructures. PMID:19113298</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/804146','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/804146"><span id="translatedtitle">Measurement of the Induced Proton Polarization <span class="hlt">Pn</span> in the 12C(e, e', p) reaction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Woo, R J; Barkhuff, David; Bertozzi, William; Chen, Jian-ping; Dale, Dan; Dodson, G; Dow, K A; Epstein, Marty; Farkhondeh, Manouchehr; Finn, Mike; Gilad, Shalev; Jones, Mark K; Joo, Kyungseon; Kelly, James; Kowalski, Stanley; Lourie, Bob; Madey, Richard; Margaziotis, Dimitri; Markowitz, Pete; McIntyre, Justin; Mertz, Christoph; Milbrath, Brian; Mitchell, Joseph; Perdrisat, Charles F; Punjabi, Vina; Rutt, Paul; Sarty, Adam; Tieger, D; Tschalaer, C; Turchinetz, William; Ulmer, Paul E; Van Verst, S P; Vellidis, C; Warren, Glen; Weinstein, Lawrence</p> <p>1998-01-19</p> <p>The first measurements of the induced proton polarization <span class="hlt">Pn</span> for the 12C(e,e',p) reaction are reported. The experiment was performed at quasifree kinematics for energy and momentum transfer (w,q) = (294 MeV, 765 MeV/c) and sampled a missing momentum range of 0-250 MeV/c. The induced polarization arises from final-state interactions and for these kinematics is dominated by the real part of the spin-orbit optical potential. The distorted-wave impulse approximation provides good agreement with data for the 1 p3/2 shell. The data for the continuum suggest that both the 1s1/2 shell and underlying l > 1 configurations contribute.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/14382','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/14382"><span id="translatedtitle">Inductively Coupled Plasma-Induced Etch Damage of GaN <span class="hlt">p-n</span> Junctions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>SHUL,RANDY J.; ZHANG,LEI; BACA,ALBERT G.; WILLISON,CHRISTI LEE; HAN,JUNG; PEARTON,S.J.; REN,F.</p> <p>1999-11-03</p> <p>Plasma-induced etch damage can degrade the electrical and optical performance of III-V nitride electronic and photonic devices. We have investigated the etch-induced damage of an Inductively Coupled Plasma (ICP) etch system on the electrical performance of mesa-isolated GaN <span class="hlt">pn</span>-junction diodes. GaN p-i-n mesa diodes were formed by Cl{sub 2}/BCl{sub 3}/Ar ICP etching under different plasma conditions. The reverse leakage current in the mesa diodes showed a strong relationship to chamber pressure, ion energy, and plasma flux. Plasma induced damage was minimized at moderate flux conditions ({le} 500 W), pressures {ge}2 mTorr, and at ion energies below approximately -275 V.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013NatCo...4E2525C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013NatCo...4E2525C"><span id="translatedtitle">Complete gate control of supercurrent in graphene <span class="hlt">p-n</span> junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Choi, Jae-Hyun; Lee, Gil-Ho; Park, Sunghun; Jeong, Dongchan; Lee, Jeong-O.; Sim, H.-S.; Doh, Yong-Joo; Lee, Hu-Jong</p> <p>2013-09-01</p> <p>In a conventional Josephson junction of graphene, the supercurrent is not turned off even at the charge neutrality point, impeding further development of superconducting quantum information devices based on graphene. Here we fabricate bipolar Josephson junctions of graphene, in which a <span class="hlt">p-n</span> potential barrier is formed in graphene with two closely spaced superconducting contacts, and realize supercurrent ON/OFF states using electrostatic gating only. The bipolar Josephson junctions of graphene also show fully gate-driven macroscopic quantum tunnelling behaviour of Josephson phase particles in a potential well, where the confinement energy is gate tuneable. We suggest that the supercurrent OFF state is mainly caused by a supercurrent dephasing mechanism due to a random pseudomagnetic field generated by ripples in graphene, in sharp contrast to other nanohybrid Josephson junctions. Our study may pave the way for the development of new gate-tuneable superconducting quantum information devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24056682','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24056682"><span id="translatedtitle">Complete gate control of supercurrent in graphene <span class="hlt">p-n</span> junctions.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Choi, Jae-Hyun; Lee, Gil-Ho; Park, Sunghun; Jeong, Dongchan; Lee, Jeong-O; Sim, H-S; Doh, Yong-Joo; Lee, Hu-Jong</p> <p>2013-01-01</p> <p>In a conventional Josephson junction of graphene, the supercurrent is not turned off even at the charge neutrality point, impeding further development of superconducting quantum information devices based on graphene. Here we fabricate bipolar Josephson junctions of graphene, in which a <span class="hlt">p-n</span> potential barrier is formed in graphene with two closely spaced superconducting contacts, and realize supercurrent ON/OFF states using electrostatic gating only. The bipolar Josephson junctions of graphene also show fully gate-driven macroscopic quantum tunnelling behaviour of Josephson phase particles in a potential well, where the confinement energy is gate tuneable. We suggest that the supercurrent OFF state is mainly caused by a supercurrent dephasing mechanism due to a random pseudomagnetic field generated by ripples in graphene, in sharp contrast to other nanohybrid Josephson junctions. Our study may pave the way for the development of new gate-tuneable superconducting quantum information devices. PMID:24056682</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMSM13D2121L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMSM13D2121L"><span id="translatedtitle">Design of a Miniaturized Langmuir Plasma Probe for the QuadSat/<span class="hlt">Pn</span>P</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Landavazo, M.; Jorgensen, A. M.; Del Barga, C.; Ferguson, D.; Guillette, D.; Huynh, A.; Klepper, J.; Kuker, J.; Lyke, J. C.; Marohn, B.; Mason, J.; Quiroga, J.; Ravindran, V.; Yelton, C.; Zagrai, A. N.; Zufelt, B.</p> <p>2011-12-01</p> <p>We have developed a miniaturized Langmuir plasma probe for measuring plasma density in low-earth orbit. Measuring plasma density in the upper ionosphere is important as a diagnostic for the rest of the ionosphere and as an input to space weather forecasting models. Developing miniaturized instrumentation allows easier deployment of a large number of small satellites for monitoring space weather. Our instrument was designed for the Swedish QuadSat/<span class="hlt">Pn</span>P, with the following constraints: A volume constraint of 5x5x1.25cm for the electronics enclosure, a mass budget 100 g, and a power budget of 0.5 W. We met the volume and mass constraints and where able to use less power than budgeted, only 0.25 W. We designed the probe for a bias range of +/-15V and current measurements in the 1 nA to 1 mA range (6 orders of magnitude). Necessary voltage of +/- 15 V and 3.3 V were generated on-board from a single 5 V supply. The electronics suite is based off carefully selected yet affordable commercial components that exhibit low noise, low leakage currents and low power consumption. Size constraints, low noise and low leakage requirements called for a carefully designed four layer PCB with a properly guarded current path using surface mount components on both sides. An ultra-low power microcontroller handles instrument functionality and is fully controllable over i2c using SPA-1 space plug and play. We elected for a probe launched deployed, which required careful design to survive launch vibrations while staying within the mass budget. The QuadSat/<span class="hlt">Pn</span>P has not been launched at the time of writing. We will present details of the instrument design and initial calibration data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/974862','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/974862"><span id="translatedtitle">A crust and upper mantle model of Eurasia and North Africa for <span class="hlt">Pn</span> travel time calculation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Myers, S; Begnaud, M; Ballard, S; Pasyanos, M; Phillips, W S; Ramirez, A; Antolik, M; Hutchenson, K; Dwyer, J; Rowe, C; Wagner, G</p> <p>2009-03-19</p> <p>We develop a Regional Seismic Travel Time (RSTT) model and methods to account for the first-order effect of the three-dimensional crust and upper mantle on travel times. The model parameterization is a global tessellation of nodes with a velocity profile at each node. Interpolation of the velocity profiles generates a 3-dimensional crust and laterally variable upper mantle velocity. The upper mantle velocity profile at each node is represented as a linear velocity gradient, which enables travel time computation in approximately 1 millisecond. This computational speed allows the model to be used in routine analyses in operational monitoring systems. We refine the model using a tomographic formulation that adjusts the average crustal velocity, mantle velocity at the Moho, and the mantle velocity gradient at each node. While the RSTT model is inherently global and our ultimate goal is to produce a model that provides accurate travel time predictions over the globe, our first RSTT tomography effort covers Eurasia and North Africa, where we have compiled a data set of approximately 600,000 <span class="hlt">Pn</span> arrivals that provide path coverage over this vast area. Ten percent of the tomography data are randomly selected and set aside for testing purposes. Travel time residual variance for the validation data is reduced by 32%. Based on a geographically distributed set of validation events with epicenter accuracy of 5 km or better, epicenter error using 16 <span class="hlt">Pn</span> arrivals is reduced by 46% from 17.3 km (ak135 model) to 9.3 km after tomography. Relative to the ak135 model, the median uncertainty ellipse area is reduced by 68% from 3070 km{sup 2} to 994 km{sup 2}, and the number of ellipses with area less than 1000 km{sup 2}, which is the area allowed for onsite inspection under the Comprehensive Nuclear Test Ban Treaty, is increased from 0% to 51%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4742690','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4742690"><span id="translatedtitle">Draft Genome Sequence of Bacillus cecembensis <span class="hlt">PN</span>5T (DSM 21993), a Psychrotolerant Bacterium Isolated from Soil Samples near the Pindari Glacier</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Wang, Jie-ping; Liu, Guo-hong; Ge, Ci-bin; Chen, Qian-qian; Che, Jian-mei; Chen, De-ju</p> <p>2016-01-01</p> <p>Bacillus cecembensis <span class="hlt">PN</span>5T is a Gram-positive, aerobic, and spore-forming bacterium with very high intrinsic heat resistance. Here, we report the 4.72-Mb draft genome sequence of B. cecembensis <span class="hlt">PN</span>5T, the first genome sequence of this species, which will promote its fundamental research. PMID:26847893</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27335271','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27335271"><span id="translatedtitle">Electrostatically tunable lateral MoTe2 <span class="hlt">p-n</span> junction for use in high-performance optoelectronics.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Zhenxing; Wang, Feng; Yin, Lei; Huang, Yun; Xu, Kai; Wang, Fengmei; Zhan, Xueying; He, Jun</p> <p>2016-07-21</p> <p>Because of their ultimate thickness, layered structure and high flexibility, <span class="hlt">pn</span> junctions based on layered two-dimensional semiconductors have been attracting increasing attention recently. In this study, for the first time, we fabricated lateral <span class="hlt">pn</span> junctions (LPNJs) based on ultrathin MoTe2 by introducing two separated electrostatic back gates, and investigated their electronic and photovoltaic performance. <span class="hlt">Pn</span>, np, nn, and pp junctions can be easily realized by modulating the conductive channel type using gate voltages with different polarities. Strong rectification effects were observed in the <span class="hlt">pn</span> and np junctions and the rectification ratio reached ∼5 × 10(4). Importantly, we find a unique phenomenon that the parameters for MoTe2 LPNJs experience abrupt changes during the transition from p to n or n to p. Furthermore, a high performance photovoltaic device with a filling factor of above 51% and electrical conversion efficiency (η) of around 0.5% is achieved. Our findings are of importance to comprehensively understand the electronic and optoelectronic properties of MoTe2 and may further open up novel electronic and optoelectronic device applications. PMID:27335271</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApPhL.108n2104Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApPhL.108n2104Q"><span id="translatedtitle">Semiconducting ZnSnN2 thin films for Si/ZnSnN2 <span class="hlt">p-n</span> junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Qin, Ruifeng; Cao, Hongtao; Liang, Lingyan; Xie, Yufang; Zhuge, Fei; Zhang, Hongliang; Gao, Junhua; Javaid, Kashif; Liu, Caichi; Sun, Weizhong</p> <p>2016-04-01</p> <p>ZnSnN2 is regarded as a promising photovoltaic absorber candidate due to earth-abundance, non-toxicity, and high absorption coefficient. However, it is still a great challenge to synthesize ZnSnN2 films with a low electron concentration, in order to promote the applications of ZnSnN2 as the core active layer in optoelectronic devices. In this work, polycrystalline and high resistance ZnSnN2 films were fabricated by magnetron sputtering technique, then semiconducting films were achieved after post-annealing, and finally Si/ZnSnN2 <span class="hlt">p-n</span> junctions were constructed. The electron concentration and Hall mobility were enhanced from 2.77 × 1017 to 6.78 × 1017 cm-3 and from 0.37 to 2.07 cm2 V-1 s-1, corresponding to the annealing temperature from 200 to 350 °C. After annealing at 300 °C, the <span class="hlt">p-n</span> junction exhibited the optimum rectifying characteristics, with a forward-to-reverse ratio over 103. The achievement of this ZnSnN2-based <span class="hlt">p-n</span> junction makes an opening step forward to realize the practical application of the ZnSnN2 material. In addition, the nonideal behaviors of the <span class="hlt">p-n</span> junctions under both positive and negative voltages are discussed, in hope of suggesting some ideas to further improve the rectifying characteristics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JQSRT.172...98G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JQSRT.172...98G"><span id="translatedtitle">Development of high-order <span class="hlt">PN</span> models for radiative heat transfer in special geometries and boundary conditions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ge, Wenjun; Modest, Michael F.; Roy, Somesh P.</p> <p>2016-03-01</p> <p>The high-order spherical harmonics (<span class="hlt">PN</span>) method for 2-D Cartesian domains is extracted from the 3-D formulation. The number of equations and intensity coefficients reduces to (N + 1)2 / 4 in the 2-D Cartesian formulation compared with N(N + 1) / 2 for the general 3-D <span class="hlt">PN</span> formulation. The Marshak boundary conditions are extended to solve problems with nonblack and mixed diffuse-specular surfaces. Additional boundary conditions for specified radiative wall flux, for symmetry/specular reflection boundaries have also been developed. The mathematical details of the formulations and their implementation in the OpenFOAM finite volume based CFD software platform are presented. The accuracy and computational cost of the 2-D Cartesian <span class="hlt">PN</span> are compared with that of the 3-D <span class="hlt">PN</span> solver and a Photon Monte Carlo solver for a square enclosure, as well as a 45° wedge geometry with variable radiative properties. The new boundary conditions have been applied for both test cases, and the boundary condition for mixed diffuse-specular surfaces is further illustrated by numerical examples of a rectangular geometry enclosed by walls with different surface characteristics.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007TJPh...31....7B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007TJPh...31....7B"><span id="translatedtitle">Exact Analytical Solution of the Diode Ideality Factor of a <span class="hlt">pn</span> Junction Device Using Lambert W-function Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bayhan, Habíbe; Sertap Kavasoglu, A.</p> <p>2007-01-01</p> <p>The paper presents a new analytical method for extracting the diode ideality factor of a <span class="hlt">p-n</span> junction device using Lambert W-function model and the dark current-voltage data. The extracted values are found to be in good agreement with those calculated experimentally from dark current-voltage characteristics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012JAP...112d4507S&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012JAP...112d4507S&link_type=ABSTRACT"><span id="translatedtitle">Organic/inorganic hybrid <span class="hlt">pn</span>-junction between copper phthalocyanine and CdSe quantum dot layers as solar cells</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saha, Sudip K.; Guchhait, Asim; Pal, Amlan J.</p> <p>2012-08-01</p> <p>We have introduced an organic/inorganic hybrid <span class="hlt">pn</span>-junction for solar cell applications. Layers of II-VI quantum dots and a metal-phthalocyanine in sequence have been used as n- and p-type materials, respectively, to form a junction. The film of quantum dots has been formed through a layer-by-layer process by replacing the long-chain ligands of the nanoparticles in each ultrathin layer or a monolayer with short-chain ones so that interparticle distance becomes small leading to a decrease in resistance of the quantum dot layer. With indium tin oxide and Au as electrodes, we have formed an inverted sandwiched structure. These electrodes formed ohmic contacts with the neighboring materials. From the current-voltage characteristics of the hybrid heterostructure, we have inferred formation of a depletion region at the <span class="hlt">pn</span>-junction that played a key role in charge separation and correspondingly a photocurrent in the external circuit. For comparison, we have also formed and characterized Schottky devices based on components of the <span class="hlt">pn</span>-junction keeping the electrode combination same. From capacitance-voltage characteristics, we have observed that the depletion region of the hybrid <span class="hlt">pn</span>-junction was much wider as compared to that in Schottky devices based on components of the junction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26335856','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26335856"><span id="translatedtitle">Gate-tunable diode and photovoltaic effect in an organic-2D layered material <span class="hlt">p-n</span> junction.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Vélez, Saül; Ciudad, David; Island, Joshua; Buscema, Michele; Txoperena, Oihana; Parui, Subir; Steele, Gary A; Casanova, Fèlix; van der Zant, Herre S J; Castellanos-Gomez, Andres; Hueso, Luis E</p> <p>2015-10-01</p> <p>The semiconducting <span class="hlt">p-n</span> junction is a simple device structure with great relevance for electronic and optoelectronic applications. The successful integration of low-dimensional materials in electronic circuits has opened the way forward for producing gate-tunable <span class="hlt">p-n</span> junctions. In that context, we present here an organic (Cu-phthalocyanine)-2D layered material (MoS2) hybrid <span class="hlt">p-n</span> junction with both gate-tunable diode characteristics and photovoltaic effect. Our proof-of-principle devices show multifunctional properties with diode rectifying factors of up to 10(4), while under light exposure they exhibit photoresponse with a measured external quantum efficiency of ∼11%. As for their photovoltaic properties, we found open circuit voltages of up to 0.6 V and optical-to-electrical power conversion efficiency of 0.7%. The extended catalogue of known organic semiconductors and two-dimensional materials offer the prospect for tailoring the properties and the performance of the resulting devices, making organic-2D <span class="hlt">p-n</span> junctions promising candidates for future technological applications. PMID:26335856</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016SPIE.9743E..1FB&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016SPIE.9743E..1FB&link_type=ABSTRACT"><span id="translatedtitle">The behavior of series resistance of a <span class="hlt">p-n</span> junction: the diode and the solar cell cases</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bueno, Poliana H.; Costa, Diogo F.; Eick, Alexander; Carvalho, André; Monteiro, Davies W. L.</p> <p>2016-03-01</p> <p>This paper presents a comparison of the impact of the internal parasitic series resistance of a <span class="hlt">p-n</span> junction, as seen from the microelectronics and photovoltaic communities. The elusive thermal behavior of the aforementioned resistance gave this work its origin. Each community uses a different approach to interpret the operational current-voltage behavior of a <span class="hlt">p-n</span> junction, which might lead to confusion, since scientists and engineers of these two realms seldom interact. An improvement in the understanding of the different approaches will help one to better model the performance of devices based on <span class="hlt">p-n</span> junctions and therefore it will favor the performance predictions of photovoltaic cells. For diodes, series resistance is usually determined from a specific forward-bias region of the I-V curve on a semi-logarithmic scale. However, in Photovoltaics this region is not commonly reported and therefore other methods to determine Rs are employed. We mathematically modeled an experimentally obtained I-V curve with various pairs of the ideality factor and Rs and found that more than one pair accurately synthesizes the measured curve. We can conclude that the reported series resistance not only depends on physical parameters, e.g. temperature or irradiance, but also on fitting parameters, i.e. the ideality factor. Generally the behavior of a <span class="hlt">p-n</span> junction depends on its operating conditions and electrical modeling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MARK16013L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MARK16013L"><span id="translatedtitle">Negative differential resistance observed from vertical <span class="hlt">p+-n</span>+ junction device with two-dimensional black phosphorous</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, Daeyeong; Jang, Young Dae; Kweon, Jaehwan; Ryu, Jungjin; Hwang, Euyheon; Yoo, Won Jong; Samsung-SKKU Graphene/2D Center (SSGC) Collaboration</p> <p></p> <p>A vertical <span class="hlt">p+-n</span>+ homojunction was fabricated by using black phosphorus (BP) as a van der Waals two-dimensional (2D) material. The top and bottom layers of the materials were doped by chemical dopants of gold chloride (AuCl3) for p-type doping and benzyl viologen (BV) for n-type doping. The negative differential resistance (NDR) effect was clearly observed from the output curves of the fabricated BP vertical devices. The thickness range of the 2D material showing NDR and the peak to valley current ratio of NDR are found to be strongly dependent on doping condition, gate voltage, and BP's degradation level. Furthermore, the carrier transport of the <span class="hlt">p+-n</span>+ junction was simulated by using density functional theory (DFT) and non-equilibrium Green's function (NEGF). Both the experimental and simulation results confirmed that the NDR is attributed to the band-to-band tunneling (BTBT) across the 2D BP <span class="hlt">p+-n</span>+ junction, and further quantitative details on the carrier transport in the vertical <span class="hlt">p+-n</span>+ junction devices were explored, according to the analyses of the measured transfer curves and the DFT simulation results. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (2013R1A2A2A01015516).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014APS..MART37011H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014APS..MART37011H"><span id="translatedtitle">Transport Properties of <span class="hlt">p-n</span> Junctions Formed in Boron/Nitrogen Doped Carbon Nanotubes and Graphene Nanoribbons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hammouri, Mahmoud; Vasiliev, Igor</p> <p>2014-03-01</p> <p>We apply ab initio computational methods based on density functional theory to study the transport properties of <span class="hlt">p-n</span> junctions made of single-walled carbon nanotubes and graphene nanoribbons. The <span class="hlt">p-n</span> junctions are formed by doping the opposite ends of carbon nanostructures with boron and nitrogen atoms. Our calculations are carried out using the SIESTA electronic structure code combined with the generalized gradient approximation for the exchange-correlation functional. The transport properties are calculated using a self-consistent nonequilibrium Green's function method implemented in the TranSIESTA package. The modeled nanoscale <span class="hlt">p-n</span> junctions exhibit linear I-V characteristics in the forward bias and nonlinear I-V characteristics with a negative differential resistance in the reverse bias. The computed transmission spectra and the I-V characteristics of the <span class="hlt">p-n</span> junctions are compared to the results of other theoretical studies and to the available experimental data. Supported by NMSU GREG Award and by NSF CHE-1112388.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013MNRAS.430.3397B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013MNRAS.430.3397B"><span id="translatedtitle">The expansion proper motions of the extraordinary giant lobes of the planetary nebula Kj<span class="hlt">Pn</span> 8 revisited</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boumis, P.; Meaburn, J.</p> <p>2013-04-01</p> <p>The primary aim is to establish a firm value for the distance to the extraordinary planetary nebula Kj<span class="hlt">Pn</span> 8. Secondary aims are to measure the ages of the three giant lobes of this object as well as estimate the energy in the eruption, that caused the most energetic outflow, for comparison with that of an intermediate-luminosity optical transient (ILOT). For these purposes a mosaic of images in the Hα + [N II] optical emission lines has been obtained with the new Aristarchos telescope in 2011 for comparison with the images of the Kj<span class="hlt">Pn</span> 8 giant lobes present on the Palomar Observatory Sky Survey (POSSI-R) 1954 and POSSII-R 1991 plates. Expansion proper motions of features over this 57 yr baseline in the outflows are present. Using these, a firm distance to Kj<span class="hlt">Pn</span> 8 of 1.8 ± 0.3 kpc has been derived for now the angle of the latest outflow to the sky has been established from Hubble Space Telescope imagery of the nebular core. Previously, the uncertain predictions of a bow-shock model were used for this purpose. The dynamical ages of the three separate outflows that form the giant lobes of Kj<span class="hlt">Pn</span> 8 are also directly measured as 3200, 7200 and ≥5 × 104 yr, respectively, which confirms their sequential ejection. Moreover, the kinetic energy of the youngest and most energetic of these is measured as ≈1047 erg which is compatible with an ILOT origin.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4406471','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4406471"><span id="translatedtitle">Serpine2/<span class="hlt">PN</span>-1 Is Required for Proliferative Expansion of Pre-Neoplastic Lesions and Malignant Progression to Medulloblastoma</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Vaillant, Catherine; Kool, Marcel; Schwarzentruber-Schauerte, Alexandra; Méreau, Hélène; Cabuy, Erik; Lobrinus, Johannes A.; Pfister, Stefan; Zuniga, Aimée; Frank, Stephan; Zeller, Rolf</p> <p>2015-01-01</p> <p>Background Medulloblastomas are malignant childhood brain tumors that arise due to the aberrant activity of developmental pathways during postnatal cerebellar development and in adult humans. Transcriptome analysis has identified four major medulloblastoma subgroups. One of them, the Sonic hedgehog (SHH) subgroup, is caused by aberrant Hedgehog signal transduction due to mutations in the Patched1 (PTCH1) receptor or downstream effectors. Mice carrying a Patched-1 null allele (Ptch1∆/+) are a good model to study the alterations underlying medulloblastoma development as a consequence of aberrant Hedgehog pathway activity. Results Transcriptome analysis of human medulloblastomas shows that SERPINE2, also called Protease Nexin-1 (<span class="hlt">PN</span>-1) is overexpressed in most medulloblastomas, in particular in the SHH and WNT subgroups. As siRNA-mediated lowering of SERPINE2/<span class="hlt">PN</span>-1 in human medulloblastoma DAOY cells reduces cell proliferation, we analyzed its potential involvement in medulloblastoma development using the Ptch1∆/+ mouse model. In Ptch1∆/+ mice, medulloblastomas arise as a consequence of aberrant Hedgehog pathway activity. Genetic reduction of Serpine2/<span class="hlt">Pn</span>-1 interferes with medulloblastoma development in Ptch1∆/+ mice, as ~60% of the pre-neoplastic lesions (PNLs) fail to develop into medulloblastomas and remain as small cerebellar nodules. In particular the transcription factor Atoh1, whose expression is essential for development of SHH subgroup medulloblastomas is lost. Comparative molecular analysis reveals the distinct nature of the PNLs in young Ptch1∆/+<span class="hlt">Pn</span>-1Δ/+ mice. The remaining wild-type Ptch1 allele escapes transcriptional silencing in most cases and the aberrant Hedgehog pathway activity is normalized. Furthermore, cell proliferation and the expression of the cell-cycle regulators Mycn and Cdk6 are significantly reduced in PNLs of Ptch1∆/+<span class="hlt">Pn</span>-1Δ/+ mice. Conclusions Our analysis provides genetic evidence that aberrant Serpine2/<span class="hlt">Pn</span>-1 is required for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.H31H0728I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.H31H0728I"><span id="translatedtitle">Significant runoff exports of particulate nitrogen (<span class="hlt">PN</span>) with large tropical storms: Implications of climate variability for watersheds and aquatic ecosystems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Inamdar, S. P.; Dhillon, G.</p> <p>2014-12-01</p> <p>Nitrogen (N) is an important nutrient that contributes to eutrophication of water bodies and plays a key role in various terrestrial and aquatic ecosystem processes. Thus, understanding the amounts and timing of N inputs from watersheds to aquatic ecosystems is critical. Most research to date has focused on the dissolved forms (< 0.45 micron) of N such as nitrate-N and organic N, which constitute a major portion of the N flux during baseflow and small to moderate storm events. The amounts of particulate N (<span class="hlt">PN</span> > 0.45 micron) in runoff, can however, increase dramatically with large storms such as those associated with tropical depressions and hurricanes and can have a lasting impact on downstream aquatic systems. We determined the exports and storm-event patterns of <span class="hlt">PN</span> for two (12 and 79 ha) intensively instrumented, headwater, forested, catchments located in the Piedmont Region of Maryland. Stream runoff sampling has been performed for baseflow and storm events since 2011 and has included numerous large tropical storms including Irene (2011) and Sandy (2012). Key questions that we address are: How significant is the <span class="hlt">PN</span> flux, i.e., what proportion of the annual N is exported as <span class="hlt">PN</span> during the large tropical events? How does <span class="hlt">PN</span> export vary with storm magnitude? How do <span class="hlt">PN</span> exports change with catchment scale? What are the temporal patterns of dissolved and particulate N species during the largest storms? Observations for tropical storm Irene (2011) revealed that in just 59 hours this storm contributed to one-third of the annual (2011) N flux from the 12 ha watershed and 87% of this N was in particulate form. A large portion of this particulate N is likely deposited in the fluvial network, especially in headwater reaches, and could potentially become bioavailable. Understanding these contributions from large events is especially important considering that climate-change scenarios indicate increased intensity of hurricanes and tropical storms and thus potentially a greater</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991JGeo...13...13S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991JGeo...13...13S"><span id="translatedtitle">On variations of heat flow and <span class="hlt">Pn</span> velocity— A case study from the continental area of China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shaopeng, Huang; Jiyang, Wang</p> <p></p> <p>Temperature is an important factor affecting seismic velocity, and terrestrial heat flow is the direct indication of the thermal state of the lithosphere. Some authors suggested that <span class="hlt">Pn</span> velocity was closely related with heat flow. Average heat flow values ( q) and <span class="hlt">Pn</span> velocities ( VPn) from 22 regions have been calculated and collected from published literature to investigate the possible correlationship between these two parameters for the continental area of China. The regional average heat flow values vary from 43 to 99 mW m -2, corresponding to a <span class="hlt">Pn</span> velocity range of 7.6-8.4 km s -1. Results show that the variations of q and Vpn are far away from any significant inverse relation. Dependencies of seismic velocity on pressure and heat flow on crustal radiogenic heat have been taken into consideration in regressions. However, all the corrections are of little help for the improvement of the expected inverse relation. Various interpretations have been discussed. Seismic velocity is a function of multi varieties. At the depth of Moho boundary, it can at most be simplified as a function of pressure and temperature. With respect to depth, effects of geopressure and geotemperature on Vpn are of exactly the same order with opposite sign. Therefore, any meaningful q- Vpn relationship should be sensitive to the correction of pressure effect on Vpn. But even the relation for the North America (Black and Braile, 1982) is dull of pressure correction. The conclusion deduced from the present study is that temperature at the Moho boundary is not the most important factor affecting <span class="hlt">Pn</span> velocity. The conceptual inverse correlationship between heat flow and <span class="hlt">Pn</span> velocity might be masked by various "noises". The non-inverse correlationship has been interpreted as a result of the complex deep structure, unnegligible heterogeneity of the upper mantle and the thermal processes at depth of the lithosphere in the continental area of China.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013GeoJI.192..310D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013GeoJI.192..310D"><span id="translatedtitle">Uppermost mantle seismic velocity and anisotropy in the Euro-Mediterranean region from <span class="hlt">Pn</span> and Sn tomography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Díaz, J.; Gil, A.; Gallart, J.</p> <p>2013-01-01</p> <p>In the last 10-15 years, the number of high quality seismic stations monitoring the Euro-Mediterranean region has increased significantly, allowing a corresponding improvement in structural constraints. We present here new images of the seismic velocity and anisotropy variations in the uppermost mantle beneath this complex area, compiled from inversion of <span class="hlt">Pn</span> and Sn phases sampling the whole region. The method of Hearn has been applied to the traveltime arrivals of the International Seismological Center catalogue for the time period 1990-2010. A total of 579 753 <span class="hlt">Pn</span> arrivals coming from 12 377 events recorded at 1 408 stations with epicentral distances between 220 km and 1 400 km have been retained after applying standard quality criteria (maximum depth, minimum number of recordings, maximum residual values …). Our results show significant features well correlated with surface geology and evidence the heterogeneous character of the Euro-Mediterranean lithosphere. The station terms reflect the existence of marked variations in crustal thickness, consistent with available Moho depths inferred from active seismic experiments. The highest <span class="hlt">Pn</span> velocities are observed along a continuous band from the Po Basin to the northern Ionian Sea. Other high velocity zones include the Ligurian Basin, the Valencia Trough, the southern Alboran Sea and central part of the Algerian margin. Most significant low-velocity values are associated to orogenic belts (Betics, Pyrenees, Alps, Apennines and Calabrian Arc, Dinarides-Hellenides), and low-velocity zones are also identified beneath Sardinia and the Balearic Islands. The introduction of an anisotropic term enhances significantly the lateral continuity of the anomalies, in particular in the most active tectonic areas. <span class="hlt">Pn</span> anisotropy shows consistent orientations subparallel to major orogenic structures, such as Betics, Apennines, Calabrian Arc and Alps. The Sn tomographic image has lower resolution but confirms independently most of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26517577','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26517577"><span id="translatedtitle">Fast One-Pot Synthesis of MoS2/Crumpled Graphene <span class="hlt">p-n</span> Nanonjunctions for Enhanced Photoelectrochemical Hydrogen Production.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Carraro, Francesco; Calvillo, Laura; Cattelan, Mattia; Favaro, Marco; Righetto, Marcello; Nappini, Silvia; Píš, Igor; Celorrio, Verónica; Fermín, David J; Martucci, Alessandro; Agnoli, Stefano; Granozzi, Gaetano</p> <p>2015-11-25</p> <p>Aerosol processing enables the preparation of hierarchical graphene nanocomposites with special crumpled morphology in high <span class="hlt">yield</span> and in a short time. Using modular insertion of suitable precursors in the starting solution, it is possible to synthesize different types of graphene-based materials ranging from heteroatom-doped graphene nanoballs to hierarchical nanohybrids made up by nitrogen-doped crumpled graphene nanosacks that wrap finely dispersed MoS2 nanoparticles. These materials are carefully investigated by microscopic (SEM, standard and HR TEM), diffraction (grazing incidence X-ray diffraction (GIXRD)) and spectroscopic (high resolution photoemission, Raman and UV-visible spectroscopy) techniques, evidencing that nitrogen dopants provide anchoring sites for MoS2 nanoparticles, whereas crumpling of graphene sheets drastically limits aggregation. The activity of these materials is tested toward the photoelectrochemical production of hydrogen, obtaining that N-doped graphene/MoS2 nanohybrids are seven times more efficient with respect to single MoS2 because of the formation of local <span class="hlt">p-n</span> MoS2/N-doped graphene nanojunctions, which allow an efficient charge carrier separation. PMID:26517577</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=203367','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=203367"><span id="translatedtitle"><span class="hlt">YIELD</span> EDITOR: SOFTWARE FOR REMOVING ERRORS FROM CROP <span class="hlt">YIELD</span> MAPS</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p><span class="hlt">Yield</span> maps are a key component of precision agriculture, due to their usefulness in both development and evaluation of precision management strategies. The value of these <span class="hlt">yield</span> maps can be compromised by the fact that raw <span class="hlt">yield</span> maps contain a variety of inherent errors. Researchers have reported t...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012SPIE.8327E..04P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012SPIE.8327E..04P"><span id="translatedtitle"><span class="hlt">Yield</span> enhancement with DFM</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Paek, Seung Weon; Kang, Jae Hyun; Ha, Naya; Kim, Byung-Moo; Jang, Dae-Hyun; Jeon, Junsu; Kim, DaeWook; Chung, Kun Young; Yu, Sung-eun; Park, Joo Hyun; Bae, SangMin; Song, DongSup; Noh, WooYoung; Kim, YoungDuck; Song, HyunSeok; Choi, HungBok; Kim, Kee Sup; Choi, Kyu-Myung; Choi, Woonhyuk; Jeon, JoongWon; Lee, JinWoo; Kim, Ki-Su; Park, SeongHo; Chung, No-Young; Lee, KangDuck; Hong, YoungKi; Kim, BongSeok</p> <p>2012-03-01</p> <p>A set of design for manufacturing (DFM) techniques have been developed and applied to 45nm, 32nm and 28nm logic process technologies. A noble technology combined a number of potential confliction of DFM techniques into a comprehensive solution. These techniques work in three phases for design optimization and one phase for silicon diagnostics. In the DFM prevention phase, foundation IP such as standard cells, IO, and memory and P&R tech file are optimized. In the DFM solution phase, which happens during ECO step, auto fixing of process weak patterns and advanced RC extraction are performed. In the DFM polishing phase, post-layout tuning is done to improve manufacturability. DFM analysis enables prioritization of random and systematic failures. The DFM technique presented in this paper has been silicon-proven with three successful tape-outs in Samsung 32nm processes; about 5% improvement in <span class="hlt">yield</span> was achieved without any notable side effects. Visual inspection of silicon also confirmed the positive effect of the DFM techniques.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19820006353','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19820006353"><span id="translatedtitle">Secondary Electron Emission <span class="hlt">Yields</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Krainsky, I.; Lundin, W.; Gordon, W. L.; Hoffman, R. W.</p> <p>1981-01-01</p> <p>The secondary electron emission (SEE) characteristics for a variety of spacecraft materials were determined under UHV conditions using a commercial double pass CMA which permits sequential Auger electron electron spectroscopic analysis of the surface. The transparent conductive coating indium tin oxide (ITO) was examined on Kapton and borosilicate glass and indium oxide on FED Teflon. The total SEE coefficient ranges from 2.5 to 2.6 on as-received surfaces and from 1.5 to 1.6 on Ar(+) sputtered surfaces with 5 nm removed. A cylindrical sample carousel provides normal incidence of the primary beam as well as a multiple Faraday cup measurement of the approximately nA beam currents. Total and true secondary <span class="hlt">yields</span> are obtained from target current measurements with biasing of the carousel. A primary beam pulsed mode to reduce electron beam dosage and minimize charging of insulating coatings was applied to Mg/F2 coated solar cell covers. Electron beam effects on ITO were found quite important at the current densities necessary to do Auger studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26061271','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26061271"><span id="translatedtitle">Nanostructured p-type CZTS thin films prepared by a facile solution process for 3D <span class="hlt">p-n</span> junction solar cells.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Park, Si-Nae; Sung, Shi-Joon; Sim, Jun-Hyoung; Yang, Kee-Jeong; Hwang, Dae-Kue; Kim, JunHo; Kim, Gee Yeong; Jo, William; Kim, Dae-Hwan; Kang, Jin-Kyu</p> <p>2015-07-01</p> <p>Nanoporous p-type semiconductor thin films prepared by a simple solution-based process with appropriate thermal treatment and three-dimensional (3D) <span class="hlt">p-n</span> junction solar cells fabricated by depositing n-type semiconductor layers onto the nanoporous p-type thin films show considerable photovoltaic performance compared with conventional thin film <span class="hlt">p-n</span> junction solar cells. Spin-coated p-type Cu2ZnSnS4 (CZTS) thin films prepared using metal chlorides and thiourea show unique nanoporous thin film morphology, which is composed of a cluster of CZTS nanograins of 50-500 nm, and the obvious 3D <span class="hlt">p-n</span> junction structure is fabricated by the deposition of n-type CdS on the nanoporous CZTS thin films by chemical bath deposition. The photovoltaic properties of 3D <span class="hlt">p-n</span> junction CZTS solar cells are predominantly affected by the scale of CZTS nanograins, which is easily controlled by the sulfurization temperature of CZTS precursor films. The scale of CZTS nanograins determines the minority carrier transportation within the 3D <span class="hlt">p-n</span> junction between CZTS and CdS, which are closely related with the photocurrent of series resistance of 3D <span class="hlt">p-n</span> junction solar cells. 3D <span class="hlt">p-n</span> junction CZTS solar cells with nanograins below 100 nm show power conversion efficiency of 5.02%, which is comparable with conventional CZTS thin film solar cells. PMID:26061271</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015A%26A...583A..83A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015A%26A...583A..83A"><span id="translatedtitle">The physics and kinematics of the evolved, interacting planetary nebula <span class="hlt">PN</span> G342.0-01.7</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ali, A.; Amer, M. A.; Dopita, M. A.; Vogt, F. P. A.; Basurah, H. M.</p> <p>2015-11-01</p> <p>Integral field spectroscopy has been obtained for very few evolved planetary nebulae (PNe). Here we aim to study the physical and kinematical characteristics of the unstudied old planetary nebula <span class="hlt">PN</span> G342.0-01.7, which shows evidence of interaction with its surrounding interstellar medium. We used integral field spectra from the Wide Field Spectrograph on the ANU 2.3 m telescope to provide spectroscopy across the whole object covering the spectral range 3400-7000 Å. We formed narrow-band images to investigate the excitation structure. The spectral analysis shows that the object is a distant Peimbert Type I planetary nebula (<span class="hlt">PN</span>) of low excitation, formally of excitation class of 0.5. The low electron density, high dynamical age, and low surface brightness of the object confirm that it is observed fairly late in its evolution. It shows clear evidence for dredge-up of CN-processed material characteristic of its class. In addition, the low peculiar velocity of 7 km s-1 shows it to be a member of the young disk component of our Galaxy. We further determined an average expansion velocity of Vexp = 20.2 ± 1.3 km s-1, a local standard of rest radial velocity RVLSR = -27.7 ± 1.7 km s-1, and a distance of 2.06 ± 0.6 kpc for the object. We built a self-consistent photoionisation model for the <span class="hlt">PN</span> matching the observed spectrum, the Hβ luminosity, and the diameter. On the basis of this we derive an effective temperature log Teff ~ 5.05 and luminosity 1.85 < log L< 2.25. The temperature is much higher than might have been expected using the excitation class, proving that this can be misleading in classifying evolved PNe. <span class="hlt">PN</span> G342.0-01.7 is in interaction with its surrounding interstellar medium through which the object is moving in the south-west direction. This interaction drives a slow shock into the outer <span class="hlt">PN</span> ejecta. A shock model suggests that it only accounts for about 10% of the total luminosity, but has an important effect on the global spectrum of the <span class="hlt">PN</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhSS...57.1519M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhSS...57.1519M"><span id="translatedtitle">Transitions between quantum states of the spin-soliton structure in molecular magnets [Mn{( R/ S)- <span class="hlt">pn</span>}]2[Mn{( R/ S)- <span class="hlt">pn</span>}2(H2O)][Cr(CN)6]2</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Morgunov, R. B.; Kirman, M. V.; Talantsev, A. D.</p> <p>2015-08-01</p> <p>A series of jumps of the magnetic moment (up to five jumps) with an amplitude of 1-10% of the saturation magnetization has been observed upon demagnetizing the molecular magnet [Mn{( R/ S)- <span class="hlt">pn</span>}]2[Mn{( R/ S)- <span class="hlt">pn</span>}2(H2O)][Cr(CN)6]2 in a narrow region of magnetic fields close to the coercive force. A decrease in the temperature leads to an increase in the critical magnetic field, which corresponds to the onset of the series of demagnetization jumps. The obtained experimental data agree with theoretical predictions on jump-like transitions between the magnetization curves upon attaining critical magnetic fields caused by the energy quantization of spin solitons.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22012089','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22012089"><span id="translatedtitle">Synthesis and structural characterization of the ternary Zintl phases AE{sub 3}Al{sub 2}<span class="hlt">Pn</span>{sub 4} and AE{sub 3}Ga{sub 2}<span class="hlt">Pn</span>{sub 4} (AE=Ca, Sr, Ba, Eu; <span class="hlt">Pn</span>=P, As)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>He, Hua; Tyson, Chauntae; Saito, Maia; Bobev, Svilen</p> <p>2012-04-15</p> <p>Ten new ternary phosphides and arsenides with empirical formulae AE{sub 3}Al{sub 2}<span class="hlt">Pn</span>{sub 4} and AE{sub 3}Ga{sub 2}<span class="hlt">Pn</span>{sub 4} (AE=Ca, Sr, Ba, Eu; <span class="hlt">Pn</span>=P, As) have been synthesized using molten Ga, Al, and Pb fluxes. They have been structurally characterized by single-crystal and powder X-ray diffraction to form with two different structures-Ca{sub 3}Al{sub 2}P{sub 4}, Sr{sub 3}Al{sub 2}As{sub 4}, Eu{sub 3}Al{sub 2}P{sub 4}, Eu{sub 3}Al{sub 2}As{sub 4}, Ca{sub 3}Ga{sub 2}P{sub 4}, Sr{sub 3}Ga{sub 2}P{sub 4}, Sr{sub 3}Ga{sub 2}As{sub 4}, and Eu{sub 3}Ga{sub 2}As{sub 4} crystallize with the Ca{sub 3}Al{sub 2}As{sub 4} structure type (space group C2/c, Z=4); Ba{sub 3}Al{sub 2}P{sub 4} and Ba{sub 3}Al{sub 2}As{sub 4} adopt the Na{sub 3}Fe{sub 2}S{sub 4} structure type (space group Pnma, Z=4). The polyanions in both structures are made up of Tr<span class="hlt">Pn</span>{sub 4} tetrahedra, which share common corners and edges to form {sup 2}{sub {infinity}}[Tr<span class="hlt">Pn</span>{sub 2}]{sub 3-} layers in the phases with the Ca{sub 3}Al{sub 2}As{sub 4} structure, and {sup 1}{sub {infinity}}[Tr<span class="hlt">Pn</span>{sub 2}]{sub 3-} chains in Ba{sub 3}Al{sub 2}P{sub 4} and Ba{sub 3}Al{sub 2}As{sub 4} with the Na{sub 3}Fe{sub 2}S{sub 4} structure type. The valence electron count for all of these compounds follows the Zintl-Klemm rules. Electronic band structure calculations confirm them to be semiconductors. - Graphical abstract: AE{sub 3}Al{sub 2}<span class="hlt">Pn</span>{sub 4} and AE{sub 3}Ga{sub 2}<span class="hlt">Pn</span>{sub 4} (AE=Ca, Sr, Ba, Eu; <span class="hlt">Pn</span>=P, As) crystallize in two different structures-Ca{sub 3}Al{sub 2}P{sub 4}, Sr{sub 3}Al{sub 2}As{sub 4}, Eu{sub 3}Al{sub 2}P{sub 4}, Eu{sub 3}Al{sub 2}As{sub 4}, Ca{sub 3}Ga{sub 2}P{sub 4}, Sr{sub 3}Ga{sub 2}P{sub 4}, Sr{sub 3}Ga{sub 2}As{sub 4}, and Eu{sub 3}Ga{sub 2}As{sub 4}, are isotypic with the previously reported Ca{sub 3}Al{sub 2}As{sub 4} (space group C2/c (No. 15)), while Ba{sub 3}Al{sub 2}P{sub 4} and Ba{sub 3}Al{sub 2}As{sub 4} adopt a different structure known for Na{sub 3}Fe{sub 2}S{sub 4} (space group Pnma (No. 62</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=293046','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=293046"><span id="translatedtitle"><span class="hlt">Yield</span> gains in leafy vegetables</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p><span class="hlt">Yield</span> of all crops have increased during the past century through improved cultural practices and plant breeding. We reviewed gains in <span class="hlt">yield</span> of lettuce and spinach in the U.S., principally California and Arizona. We proposed several genetic models for <span class="hlt">yield</span> of lettuce based on the market type: whole...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27132492','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27132492"><span id="translatedtitle">Contacts between Two- and Three-Dimensional Materials: Ohmic, Schottky, and <span class="hlt">p-n</span> Heterojunctions.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Xu, Yang; Cheng, Cheng; Du, Sichao; Yang, Jianyi; Yu, Bin; Luo, Jack; Yin, Wenyan; Li, Erping; Dong, Shurong; Ye, Peide; Duan, Xiangfeng</p> <p>2016-05-24</p> <p>After a decade of intensive research on two-dimensional (2D) materials inspired by the discovery of graphene, the field of 2D electronics has reached a stage with booming materials and device architectures. However, the efficient integration of 2D functional layers with three-dimensional (3D) systems remains a significant challenge, limiting device performance and circuit design. In this review, we investigate the experimental efforts in interfacing 2D layers with 3D materials and analyze the properties of the heterojunctions formed between them. The contact resistivity of metal on graphene and related 2D materials deserves special attention, while the Schottky junctions formed between metal/2D semiconductor or graphene/3D semiconductor call for careful reconsideration of the physical models describing the junction behavior. The combination of 2D and 3D semiconductors presents a form of <span class="hlt">p-n</span> junctions that have just marked their debut. For each type of the heterojunctions, the potential applications are reviewed briefly. PMID:27132492</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhCS.707a2035K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhCS.707a2035K"><span id="translatedtitle">Comparison of Ge, InGaAs <span class="hlt">p-n</span> junction solar cell</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Korun, M.; Navruz, T. S.</p> <p>2016-04-01</p> <p>In this paper, the effect of material parameters on the efficiency of Ge and InGaAs <span class="hlt">p-n</span> junction solar cells which are most commonly used as the sub-cell of multi-junction solar cells are investigated and the results due to these two cells are compared. The efficiency of Ge (EG =0.67 eV) solar cell which is easy to manufacture and inexpensive in cost, is compared with the efficiency of InGaAs (EG =0.74 eV) solar cell which is coming with drawback of high production difficulties and cost. The theoretical efficiency limit of Ge and InGaAs solar cells with optimum thickness were determined by using detailed balance model under one sun AM1.5 illumination. Since the band gap values of two cells are close to each other, approximate detailed balance efficiency limits of 16% for InGaAs and 14% for Ge are obtained. When drift-diffusion model is used and the thicknesses and doping concentrations are optimized, the maximum efficiency values are calculated as 13% for InGaAs and 9% for Ge solar cell. For each solar cell external quantum efficiency curves due to wavelength are also sketched and compared.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MARL15014Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MARL15014Z"><span id="translatedtitle">RKKY interaction in <span class="hlt">P-N</span> junction based on surface states of 3D topological insulator</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Shuhui; Yang, Wen; Chang, Kai</p> <p></p> <p>The RKKY interaction mediated by conduction electrons supplies a mechanism to realize the long-range coupling of localized spins which is desired for the spin devices. Here, we examine the controllability of RKKY interaction in <span class="hlt">P-N</span> junction (PNJ) based on surface states of 3D topological insulator (3DTI). In this study, through quantum way but not usual classical analogy to light propagation, the intuitive picture for electron waves across the interface of PNJ is obtained, e.g., Klein tunneling, negative refraction and focusing. Moreover, we perform the numerical calculations for all kinds of RKKY interaction including the Heisenberg, Ising, and Dzyaloshinskii-Moriya terms. We find the focusing of surface states leads to the local augmentation of RKKY interaction. Most importantly, a dimension transition occurs, i.e., the decay rate of RKKY interaction from the deserved 1/R 2 to 1/ R . In addition, the quadratic gate-dependence of RKKY interaction is also beneficial to the application of 3DTI PNJ in the fields of spintronics and quantum computation. This work was supported by the MOST (Grant No. 2015CB921503, and No. 2014CB848700) and NSFC (Grant No. 11434010, No. 11274036, No. 11322542, and No. 11504018).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012APS..MAR.P6005A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012APS..MAR.P6005A"><span id="translatedtitle">New Aspects of Photocurrent Generation at Graphene <span class="hlt">pn</span> Junctions Revealed by Ultrafast Optical Measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aivazian, Grant; Sun, Dong; Jones, Aaron; Ross, Jason; Yao, Wang; Cobden, David; Xu, Xiaodong</p> <p>2012-02-01</p> <p>The remarkable electrical and optical properties of graphene make it a promising material for new optoelectronic applications. However, one important, but so far unexplored, property is the role of hot carriers in charge and energy transport at graphene interfaces. Here we investigate the photocurrent (PC) dynamics at a tunable graphene <span class="hlt">pn</span> junction using ultrafast scanning PC microscopy. Pump-probe measurements show a temperature dependent relaxation time of photogenerated carriers that increases from 1.5ps at 290K to 4ps at 20K; while the amplitude of the PC is independent of the lattice temperature. These observations imply that it is hot carriers, not phonons, which dominate ultrafast energy transport. Gate dependent measurements show many interesting features such as pump induced saturation, enhancement, and sign reversal of probe generated PC. These observations reveal that the underlying PC mechanism is a combination of the thermoelectric and built-in electric field effects. Our results enhance the understanding of non-equilibrium electron dynamics, electron-electron interactions, and electron-phonon interactions in graphene. They also determine fundamental limits on ultrafast device operation speeds (˜500 GHz) for graphene-based photodetectors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JAP...116o4502O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JAP...116o4502O"><span id="translatedtitle">Thermal influence on charge carrier transport in solar cells based on GaAs <span class="hlt">PN</span> junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Osses-Márquez, Juan; Calderón-Muñoz, Williams R.</p> <p>2014-10-01</p> <p>The electron and hole one-dimensional transport in a solar cell based on a Gallium Arsenide (GaAs) <span class="hlt">PN</span> junction and its dependency with electron and lattice temperatures are studied here. Electrons and heat transport are treated on an equal footing, and a cell operating at high temperatures using concentrators is considered. The equations of a two-temperature hydrodynamic model are written in terms of asymptotic expansions for the dependent variables with the electron Reynolds number as a perturbation parameter. The dependency of the electron and hole densities through the junction with the temperature is analyzed solving the steady-state model at low Reynolds numbers. Lattice temperature distribution throughout the device is obtained considering the change of kinetic energy of electrons due to interactions with the lattice and heat absorbed from sunlight. In terms of performance, higher values of power output are obtained with low lattice temperature and hot energy carriers. This modeling contributes to improve the design of heat exchange devices and thermal management strategies in photovoltaic technologies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/20662118','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/20662118"><span id="translatedtitle">Nonpolar a-plane p-type GaN and <span class="hlt">p-n</span> Junction Diodes</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chakraborty, Arpan; Xing, H.; Craven, M.D.; Keller, S.; Mates, T.; Speck, J.S.; Baars, S.P. den; Mishra, U.K.</p> <p>2004-10-15</p> <p>Growth and electrical characteristics of Mg-doped p-type nonpolar (1120) a-plane GaN films, grown on (1102) r-plane sapphire substrates via metalorganic chemical vapor deposition, were investigated as a function of growth rate, the ammonia to trimethylgallium flow ratio (V/III ratio), and the growth temperature. The electrical conductivity of the films exhibited a strong dependence on the growth parameters. Secondary-ion-mass-spectroscopy measurements indicated that more Mg was incorporated at higher growth rate and at lower growth temperatures. The Mg concentration in the films increased linearly with the Mg flow. A maximum hole concentration of 6.8x10{sup 17}cm{sup -3} was achieved at room temperature for a Mg concentration of 7.6x10{sup 19}cm{sup -3}, corresponding to 0.9% ionization. Further increase in the Mg concentration resulted in increased surface roughness as well as a significant decrease in the hole concentration. <span class="hlt">p-n</span> junction diodes were fabricated using nonpolar a-plane GaN, and the current-voltage characteristics of these diodes showed a sharp turn-on at {approx}3 V.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22308728','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22308728"><span id="translatedtitle">Carbon doping induced peculiar transport properties of boron nitride nanoribbons <span class="hlt">p-n</span> junctions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Liu, N.; Gao, G. Y.; Zhu, S. C.; Ni, Y.; Wang, S. L.; Yao, K. L.; Liu, J. B.</p> <p>2014-07-14</p> <p>By applying nonequilibrium Green's function combined with density functional theory, we investigate the electronic transport properties of carbon-doped <span class="hlt">p-n</span> nanojunction based on hexagonal boron nitride armchair nanoribbons. The calculated I-V curves show that both the center and edge doping systems present obvious negative differential resistance (NDR) behavior and excellent rectifying effect. At low positive bias, the edge doping systems possess better NDR performance with larger peak-to-valley ratio (∼10{sup 5}), while at negative bias, the obtained peak-to-valley ratio for both of the edge and center doping systems can reach the order of 10{sup 7}. Meanwhile, center doping systems present better rectifying performance than the edge doping ones, and giant rectification ratio up to 10{sup 6} can be obtained in a wide bias range. These outstanding transport properties are explained by the evolution of the transmission spectra and band structures with applied bias, together with molecular projected self-consistent Hamiltonian eigenvalues and eigenstates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000SeScT..15...51G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000SeScT..15...51G"><span id="translatedtitle">Minority electron mobility in a <span class="hlt">p-n</span> GaN photodetector</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Guan, Z. P.; Li, J. Z.; Zhang, G. Y.; Jin, S. X.; Ding, X. M.</p> <p>2000-01-01</p> <p>Photoconductive transients and responsivity in a GaN <span class="hlt">p-n</span> UV photodetector under different applied voltages are investigated at room temperature. The electron mobility of minority carriers in the p-GaN epilayer has been measured by a diffusion time-of-flight technique, and was found to be about 0.12 cm2 V-1 s-1 with the bias between 1 V and 12 V. The difference of the electron mobilities between the minority carriers in p-GaN and the majority carriers in n-GaN is explained by different scattering mechanisms. The neutral impurity and phonon scattering mechanisms dominate the minority electron mobility in p-GaN. The photoconductive responsivity increases nearly linearly at low voltage and saturates at about 10 V, corresponding to a saturation field of approximately 3.7 × 104 V cm-1 . The implication of these results for applications of GaN UV detectors is also discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22078402','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22078402"><span id="translatedtitle">UNUSUAL CARBONACEOUS DUST DISTRIBUTION IN <span class="hlt">PN</span> G095.2+00.7</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ohsawa, Ryou; Onaka, Takashi; Sakon, Itsuki; Mori, Tamami I.; Miyata, Takashi; Asano, Kentaro; Matsuura, Mikako; Kaneda, Hidehiro</p> <p>2012-12-01</p> <p>We investigate the polycyclic aromatic hydrocarbon (PAH) features in the young Galactic planetary nebula <span class="hlt">PN</span> G095.2+00.7 based on mid-infrared observations. The near- to mid-infrared spectra obtained with the AKARI/IRC and the Spitzer/IRS show the PAH features as well as the broad emission feature at 12 {mu}m usually seen in proto-planetary nebulae (pPNe). The spatially resolved spectra obtained with Subaru/COMICS suggest that the broad emission around 12 {mu}m is distributed in a shell-like structure, but the unidentified infrared band at 11.3 {mu}m is selectively enhanced at the southern part of the nebula. The variation can be explained by a difference in the amount of the UV radiation to excite PAHs, and does not necessarily require the chemical processing of dust grains and PAHs. It suggests that the UV self-extinction is important to understand the mid-infrared spectral features. We propose a mechanism which accounts for the evolutionary sequence of the mid-infrared dust features seen in a transition from pPNe to PNe.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015FrMat...2....8L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015FrMat...2....8L"><span id="translatedtitle">Room-temperature near-infrared electroluminescence from boron-diffused silicon <span class="hlt">pn</span> junction diodes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Si; Gao, Yuhan; Fan, Ruixin; Li, Dongsheng; Yang, Deren</p> <p>2015-02-01</p> <p>Silicon <span class="hlt">pn</span> junction diodes with different doping concentrations were prepared by boron diffusion into Czochralski (CZ) n-type silicon substrate. Their room-temperature near-infrared electroluminescence (EL) was measured. In the EL spectra of the heavily boron doped diode, a luminescence peak at ~1.6 μm (0.78 eV ) was observed besides the band-to-band line (~1.1eV) under the condition of high current injection, while in that of the lightly boron doped diode only the band-to-band line was observed. The intensity of peak at 0.78 eV increases exponentially with current injection with no observable saturation at room temperature. Furthermore, no dislocations were found in the cross-sectional transmission electron microscopy image, and no dislocation-related luminescence was observed in the low-temperature photoluminescence spectra. We deduce the 0.78 eV emission originates from the irradiative recombination in the strain region of diodes caused by the diffusion of large number of boron atoms into silicon crystal lattice.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008WRR....44.1421Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008WRR....44.1421Z"><span id="translatedtitle">Regional application of the <span class="hlt">Pn</span>ET-BGC model to assess historical acidification of Adirondack lakes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhai, Jing; Driscoll, Charles T.; Sullivan, Timothy J.; Cosby, Bernard J.</p> <p>2008-01-01</p> <p>The Adirondack region of New York has high inputs of acidic deposition and large numbers of acidic lakes. The biogeochemical model, <span class="hlt">Pn</span>ET-BGC, was applied to 44 statistically representative Environmental Monitoring and Assessment Program (EMAP) lake watersheds in the Adirondacks. Model simulations help provide an understanding of historical effects of acidic deposition on soils and lake waters. Model simulations indicate that median annual concentrations of SO42- and NO3- in the 44 EMAP lakes were 15.9 μeq/L and 3.8 μeq/L, respectively, in 1850, compared to the median current measured values of 88.8 μeq/L and 20.0 μeq/L. Simulated median values of pH, acid-neutralizing capacity (ANC), and soil percent base saturation were 6.63, 67.7 μeq/L, and 12.3%, respectively, in 1850, compared to the median current measured values of 5.95, 27.8 μeq/L, and 7.9%. The estimated historical surface water acidification was greatest in lakes having low ANC below values of 100 μeq/L. This pattern of historical acidification is in agreement with a previous paleolimnological investigation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006NIMPA.568..118H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006NIMPA.568..118H"><span id="translatedtitle">A high-speed <span class="hlt">pn</span>CCD detector system for optical applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hartmann, R.; Buttler, W.; Gorke, H.; Herrmann, S.; Holl, P.; Meidinger, N.; Soltau, H.; Strüder, L.</p> <p>2006-11-01</p> <p>Measurements of a frame-store <span class="hlt">pn</span>CCD detector system, optimized for high-speed applications in the optical and near infrared (NIR) region, will be presented. The device with an image area of 13.5 mm by 13.5 mm and a pixelsize of 51 μm by 51 μm exhibits a readout time faster than 1100 frames per second with an overall electronic noise contribution of less than three electrons. Variable operation modes of the detector system allow for even higher readout speeds by a pixel binning in transfer direction or, at slightly slower readout speeds, a further improvement in noise performance. We will also present the concept of a data acquisition system being able to handle pixel rates of more than 75 megapixel per second. The application of an anti-reflective coating on the ultra-thin entrance window of the back illuminated detector together with the large sensitive volume ensures a high and uniform detection efficiency from the ultra violet to the NIR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ApPhL.107r3103H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ApPhL.107r3103H"><span id="translatedtitle">A van der Waals <span class="hlt">pn</span> heterojunction with organic/inorganic semiconductors</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>He, Daowei; Pan, Yiming; Nan, Haiyan; Gu, Shuai; Yang, Ziyi; Wu, Bing; Luo, Xiaoguang; Xu, Bingchen; Zhang, Yuhan; Li, Yun; Ni, Zhenhua; Wang, Baigeng; Zhu, Jia; Chai, Yang; Shi, Yi; Wang, Xinran</p> <p>2015-11-01</p> <p>van der Waals (vdW) heterojunctions formed by two-dimensional (2D) materials have attracted tremendous attention due to their excellent electrical/optical properties and device applications. However, current 2D heterojunctions are largely limited to atomic crystals, and hybrid organic/inorganic structures are rarely explored. Here, we fabricate the hybrid 2D heterostructures with p-type dioctylbenzothienobenzothiophene (C8-BTBT) and n-type MoS2. We find that few-layer C8-BTBT molecular crystals can be grown on monolayer MoS2 by vdW epitaxy, with pristine interface and controllable thickness down to monolayer. The operation of the C8-BTBT/MoS2 vertical heterojunction devices is highly tunable by bias and gate voltages between three different regimes: interfacial recombination, tunneling, and blocking. The <span class="hlt">pn</span> junction shows diode-like behavior with rectifying ratio up to 105 at the room temperature. Our devices also exhibit photovoltaic responses with a power conversion efficiency of 0.31% and a photoresponsivity of 22 mA/W. With wide material combinations, such hybrid 2D structures will offer possibilities for opto-electronic devices that are not possible from individual constituents.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/19488110','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/19488110"><span id="translatedtitle">Frequency domain measurements on turbid media with strong absorption using the <span class="hlt">PN</span> approximation.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Baltes, Christof; Faris, Gregory W</p> <p>2009-06-01</p> <p>We have applied the frequency-domain technique to measurement of the optical properties of turbid media with strong absorption in the infinite medium limit. Absorption coefficients up to 2.3 cm(-1) for a modified scattering coefficient of 4.3 cm(-1) are studied, which corresponds to a reduced scattering albedo of 0.65. Low phase noise and good phase stability are required for these low albedo conditions. As the degree of absorption increases, the phase changes are reduced while amplitude changes increase. For this reason, correction of amplitude-phase cross talk is essential to achieve accurate measurements with strong absorption. Careful control of stray reflections is required to properly measure amplitude-phase cross talk. Because the diffusion approximation becomes less accurate, measurements are compared to calculations performed in the <span class="hlt">PN</span> approximation, which is essentially an exact solution for the infinite medium limit. Agreement between theory and experiment is only obtained when correction for amplitude-phase cross talk is performed. These measurements can provide a good method for testing amplitude-phase cross talk. PMID:19488110</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MAR.Y5012L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MAR.Y5012L"><span id="translatedtitle">Coherent control of single spins in a silicon carbide <span class="hlt">pn</span> junction device at room temperature</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, Sang-Yun; Widmann, Matthias; Booker, Ian; Niethammer, Matthias; Ohshima, Takeshi; Gali, Adam; Son, Nguyen T.; Janzén, Erik; Wrachtrup, Joerg</p> <p></p> <p>Spins in single defects have been studied for quantum information science and quantum metrology. It has been proven that spins of the single nitrogen-vacancy (NV) centers in diamond can be used as a quantum bit, and a single spin sensor operating at ambient conditions. Recently, there has been a growing interest in a new material in which color centers similar to NV centers can be created and whose electrical properties can also be well controlled, thus existing electronic devices can easily be adapted as a platform for quantum applications. We recently reported that single spins of negatively charged silicon vacancies in SiC can be coherently controlled and long-lived at room temperature. As a next step, we isolated single silicon vacancies in a SiC <span class="hlt">pn</span> junction device and investigated how the change in Fermi level, induced by applying bias, alters the charge state of silicon vacancies, thus affects the spin state control. This study will allow us to envision quantum applications based on single defects incorporated in modern electronic devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22486011','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22486011"><span id="translatedtitle">A van der Waals <span class="hlt">pn</span> heterojunction with organic/inorganic semiconductors</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>He, Daowei; Yang, Ziyi; Wu, Bing; Xu, Bingchen; Zhang, Yuhan; Li, Yun; Shi, Yi E-mail: xrwang@nju.edu.cn; Wang, Xinran E-mail: xrwang@nju.edu.cn; Pan, Yiming; Wang, Baigeng; Nan, Haiyan; Luo, Xiaoguang; Ni, Zhenhua; Gu, Shuai; Zhu, Jia; Chai, Yang</p> <p>2015-11-02</p> <p>van der Waals (vdW) heterojunctions formed by two-dimensional (2D) materials have attracted tremendous attention due to their excellent electrical/optical properties and device applications. However, current 2D heterojunctions are largely limited to atomic crystals, and hybrid organic/inorganic structures are rarely explored. Here, we fabricate the hybrid 2D heterostructures with p-type dioctylbenzothienobenzothiophene (C{sub 8}-BTBT) and n-type MoS{sub 2}. We find that few-layer C{sub 8}-BTBT molecular crystals can be grown on monolayer MoS{sub 2} by vdW epitaxy, with pristine interface and controllable thickness down to monolayer. The operation of the C{sub 8}-BTBT/MoS{sub 2} vertical heterojunction devices is highly tunable by bias and gate voltages between three different regimes: interfacial recombination, tunneling, and blocking. The <span class="hlt">pn</span> junction shows diode-like behavior with rectifying ratio up to 10{sup 5} at the room temperature. Our devices also exhibit photovoltaic responses with a power conversion efficiency of 0.31% and a photoresponsivity of 22 mA/W. With wide material combinations, such hybrid 2D structures will offer possibilities for opto-electronic devices that are not possible from individual constituents.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22305845','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22305845"><span id="translatedtitle">Thermal influence on charge carrier transport in solar cells based on GaAs <span class="hlt">PN</span> junctions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Osses-Márquez, Juan; Calderón-Muñoz, Williams R.</p> <p>2014-10-21</p> <p>The electron and hole one-dimensional transport in a solar cell based on a Gallium Arsenide (GaAs) <span class="hlt">PN</span> junction and its dependency with electron and lattice temperatures are studied here. Electrons and heat transport are treated on an equal footing, and a cell operating at high temperatures using concentrators is considered. The equations of a two-temperature hydrodynamic model are written in terms of asymptotic expansions for the dependent variables with the electron Reynolds number as a perturbation parameter. The dependency of the electron and hole densities through the junction with the temperature is analyzed solving the steady-state model at low Reynolds numbers. Lattice temperature distribution throughout the device is obtained considering the change of kinetic energy of electrons due to interactions with the lattice and heat absorbed from sunlight. In terms of performance, higher values of power output are obtained with low lattice temperature and hot energy carriers. This modeling contributes to improve the design of heat exchange devices and thermal management strategies in photovoltaic technologies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApPhL.108h3101H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApPhL.108h3101H"><span id="translatedtitle">Tunable electronic structure of black phosphorus/blue phosphorus van der Waals <span class="hlt">p-n</span> heterostructure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huang, Le; Li, Jingbo</p> <p>2016-02-01</p> <p>First principles calculations are used to explore the structural and electronic properties of black phosphorus/blue phosphorus (black-p/blue-p) van der Waals (vdW) <span class="hlt">p-n</span> heterostructure. An intrinsic type-II band alignment with a direct band gap at Γ point is demonstrated. The spatial separation of the lowest energy electron-hole pairs can be realized and make black-p/blue-p heterostructure a good candidate for applications in optoelectronics. Black-p/blue-p heterostructure exhibits modulation of its band gap and band edges by applied perpendicular electric field ( E⊥ ). This system undergoes a transition from semiconductor to metal when subjected to a strong external E⊥ . The variation of band edges and quasi-Fermi level as a function of E⊥ provides further insight to the linear variation of the band gap. Our calculation results pave the way for experimental research and indicate the great application potential of black-p/blue-p vdW heterostructure in future optoelectronics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/863317','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/863317"><span id="translatedtitle">Method for forming <span class="hlt">p-n</span> junctions and solar-cells by laser-beam processing</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Narayan, Jagdish; Young, Rosa T.</p> <p>1979-01-01</p> <p>This invention is an improved method for preparing <span class="hlt">p-n</span> junction devices, such as diodes and solar cells. High-quality junctions are prepared by effecting laser-diffusion of a selected dopant into silicon by means of laser pulses having a wavelength of from about 0.3 to 1.1 .mu.m, an energy area density of from about 1.0 to 2.0 J/cm.sup.2, and a duration of from about 20 to 60 nanoseconds. Initially, the dopant is deposited on the silicon as a superficial layer, preferably one having a thickness in the range of from about 50 to 100 A. Depending on the application, the values for the above-mentioned pulse parameters are selected to produce melting of the silicon to depths in the range from about 1000 A to 1 .mu.m. The invention has been used to produce solar cells having a one-sun conversion efficiency of 10.6%, these cells having no antireflective coating or back-surface fields.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ResPh...5..144T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ResPh...5..144T"><span id="translatedtitle">Characterization of a <span class="hlt">PN</span>3 personal neutron dosimeter based on (n,α) reaction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Traoré, I.; Nachab, A.; Nourreddine, A.; Bâ, A.</p> <p></p> <p>This study describes a new methodology for characterizing the sensitivity of personal neutron dose-equivalent dosimeters consisting of a <span class="hlt">PN</span>3 (trade name of the CR-39 type) nuclear track detector coupled with a natural boron converter BN1 (20% 10B, 80% 11B) and enriched boron converter 10B (99% 10B). Both dosimeters (converter + detector) were mounted in an ISO water-filled phantom and were simultaneously irradiated in terms of personal dose equivalent Hp(10) ranging between 1 and 4 mSv under standard neutron radiation fields generated by (252Cf + D2O) and (252Cf + D2O)/Cd) sources. After irradiation, the latent tracks produced by alpha particles were revealed through a chemical solution. The optimum etching conditions (6.25 N, 70 °C for 7 h) used, were performed for an initial in-depth study. The response of the dosimeter was given by the ratio of the average track density obtained by subtracting the tracks due to the 252Cf + D2O and (252Cf + D2O)/Cd sources to the dose equivalent. The calibration factor was found to be 2826 ± 17 tracks.cm-2.mSv-1. The sensitivity of the dosimeter was observed to be increased significantly using a converter enriched in 10B (99% 10B).</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19810037464&hterms=Manchester&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DManchester','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19810037464&hterms=Manchester&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DManchester"><span id="translatedtitle">Carrier phase recovery performance for <span class="hlt">PN</span>-spread TDRSS link with radio-frequency interference</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mckenzie, T. M.; Braun, W. R.</p> <p>1979-01-01</p> <p>The carrier-phase recovery performance of a Costas loop for a nonlinear satellite channel with uplink and downlink noise is analyzed, and the extension of these results to the case where uplink radio-frequency interference (RFI) is present is considered. The signal format here is binary phase-shift-keyed (BPSK) or unbalanced quaternary phase-shift-keyed (UQPSK), the signals being either the non-return-to-zero (NRZ) or biphase (Manchester) type. With UQPSK, at least one data stream must be <span class="hlt">PN</span>-spread. The channel comprises additive white Gaussian noise (WGN), a wideband filter, a bandpass nonlinearity and more additive WGN. The RFI being considered is pulsed continuous-wave, pulsed WGN, or a combination of the two. It is noted that the Tracking and Data Relay Satellite System (TDRSS) will be subjected to RFI from certain locations, especially in the S-band of frequencies. The characteristics of this link are generalized to form the assumptions underlying this analysis. The analytical results given include the S-curve of the equivalent loop and the phase-error variance of the linearized loop.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3161540','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3161540"><span id="translatedtitle">Common-path interference and oscillatory Zener tunneling in bilayer graphene <span class="hlt">p-n</span> junctions</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Nandkishore, Rahul; Levitov, Leonid</p> <p>2011-01-01</p> <p>Interference and tunneling are two signature quantum effects that are often perceived as the yin and yang of quantum mechanics: a particle simultaneously propagating along several distinct classical paths versus a particle penetrating through a classically inaccessible region via a single least-action path. Here we demonstrate that the Dirac quasiparticles in graphene provide a dramatic departure from this paradigm. We show that Zener tunneling in gapped bilayer graphene, which governs transport through <span class="hlt">p-n</span> heterojunctions, exhibits common-path interference that takes place under the tunnel barrier. Due to a symmetry peculiar to the gapped bilayer graphene bandstructure, interfering tunneling paths form conjugate pairs, giving rise to high-contrast oscillations in transmission as a function of the gate-tunable bandgap and other control parameters of the junction. The common-path interference is solely due to forward-propagating waves; in contrast to Fabry–Pérot-type interference in resonant-tunneling structures, it does not rely on multiple backscattering. The oscillations manifest themselves in the junction I–V characteristic as N-shaped branches with negative differential conductivity. The negative dI/dV, which arises solely due to under-barrier interference, can enable new high-speed active-circuit devices with architectures that are not available in electronic semiconductor devices. PMID:21825159</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22888862','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22888862"><span id="translatedtitle">Quantitative thermopower profiling across a silicon <span class="hlt">p-n</span> junction with nanometer resolution.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lee, Byeonghee; Kim, Kyeongtae; Lee, Seungkoo; Kim, Jong Hoon; Lim, Dae Soon; Kwon, Ohmyoung; Lee, Joon Sik</p> <p>2012-09-12</p> <p>Thermopower (S) profiling with nanometer resolution is essential for enhancing the thermoelectric figure of merit, ZT, through the nanostructuring of materials and for carrier density profiling in nanoelectronic devices. However, only qualitative and impractical methods or techniques with low resolutions have been reported thus far. Herein, we develop a quantitative S profiling method with nanometer resolution, scanning Seebeck microscopy (SSM), and batch-fabricate diamond thermocouple probes to apply SSM to silicon, which requires a contact stress higher than 10 GPa for stable electrical contact. The distance between the positive and negative peaks of the S profile across the silicon <span class="hlt">p-n</span> junction measured by SSM is 4 nm, while the theoretical distance is 2 nm. Because of its extremely high spatial resolution, quantitative measurement, and ease of use, SSM could be a crucial tool not only for the characterization of nano-thermoelectric materials and nanoelectronic devices but also for the analysis of nanoscale thermal and electrical phenomena in general. PMID:22888862</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ApJ...760L..34O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ApJ...760L..34O"><span id="translatedtitle">Unusual Carbonaceous Dust Distribution in <span class="hlt">PN</span> G095.2+00.7</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ohsawa, Ryou; Onaka, Takashi; Sakon, Itsuki; Mori, Tamami I.; Miyata, Takashi; Asano, Kentaro; Matsuura, Mikako; Kaneda, Hidehiro</p> <p>2012-12-01</p> <p>We investigate the polycyclic aromatic hydrocarbon (PAH) features in the young Galactic planetary nebula <span class="hlt">PN</span> G095.2+00.7 based on mid-infrared observations. The near- to mid-infrared spectra obtained with the AKARI/IRC and the Spitzer/IRS show the PAH features as well as the broad emission feature at 12 μm usually seen in proto-planetary nebulae (pPNe). The spatially resolved spectra obtained with Subaru/COMICS suggest that the broad emission around 12 μm is distributed in a shell-like structure, but the unidentified infrared band at 11.3 μm is selectively enhanced at the southern part of the nebula. The variation can be explained by a difference in the amount of the UV radiation to excite PAHs, and does not necessarily require the chemical processing of dust grains and PAHs. It suggests that the UV self-extinction is important to understand the mid-infrared spectral features. We propose a mechanism which accounts for the evolutionary sequence of the mid-infrared dust features seen in a transition from pPNe to PNe. Based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014apn6.confE.114B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014apn6.confE.114B"><span id="translatedtitle">A robust expansion proper motion distance to the extraordinary planetary nebula Kj<span class="hlt">Pn</span> 8</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boumis, P.; Meaburn, J.</p> <p>2014-04-01</p> <p>Since the discovery by Lopez, Vasquez and Rodriguez of the giant lobes projecting from the otherwise innocuous planetary nebula, Kj<span class="hlt">Pn</span> 8, it has been imperative to obtain a robust distance (D) determination. This has now been achieved by comparing an image of the lobes taken in 2011 with the Greek Aristarchos telescope with that (POSSI-R) obtained in 1954: the baseline for expansive proper motions has therefore being extended to 57 yr. These proper motions, combined with previous radial velocity measurements and tilt of the most energetic outflow with respect to the sight line, as determined from HST imagery of the nebular core, give D = 1.8 ± 0.3 kpc. This value then lets the kinetic energy (approx 1047 erg) of the most recent and energetic outflow to be determined. It could be significant that this energy is consistent with an Intermediate Luminosity Optical Transient (ILOT) origin of the latest ejection as proposed for other similar objects by Soker and Kashi.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013APS..MAR.N8007H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013APS..MAR.N8007H"><span id="translatedtitle"><span class="hlt">p-n</span> junction photodetectors based on macroscopic single-walled carbon nanotube films</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>He, Xiaowei; Nanot, Sébastien; Hauge, Robert H.; Kono, Junichiro</p> <p>2013-03-01</p> <p>Single-Wall carbon nanotubes (SWCNTs) are promising in use of solar technology and photodetection. There have been many reports about photovoltaic effect in nanoelectronic devices based on individual SWCNTs, but they are limited by miniscule absorption. There has been a growing trend for merging SWNTs into mico- and macroscopic devices to provide more practical applications. Here we report <span class="hlt">p-n</span> junction photodetectors based on macroscopic SWCNTs film. Factors affecting the PV amplitude and response time have been studied, including substrates, doping level. The maximal responsivity ~ 1 V/W was observed with samples on Teflon tapes, while a fast response time ~ 80 μs was observed with samples on AlN substrates. Hence an optimal combination of photoresponse time and amplitude can be found by choosing proper substrates. We found that the PV amplitude increases nonlinearly with increasing n-doping concentration, indicating the existence of an optimal doping concentration. Finally, we checked photoresponse in a wide wavelength range (360 to 900 nm), and PV was observed throughout, indicating that the device could potential be used as a broadband photodetector.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19930054997&hterms=P-n+junction&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DP-n%2Bjunction','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19930054997&hterms=P-n+junction&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DP-n%2Bjunction"><span id="translatedtitle">Greatly improved 3C-SiC <span class="hlt">p-n</span> junction diodes grown by chemical vapor deposition</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Neudeck, Philip G.; Larkin, David J.; Starr, Jonathan E.; Powell, J. A.; Salupo, Carl S.; Matus, Lawrence G.</p> <p>1993-01-01</p> <p>This paper reports the fabrication and initial electrical characterization of greatly improved 3C-SiC (beta-SiC) <span class="hlt">p-n</span> junction diodes. These diodes, which were grown on commercially available 6H-SiC substrates by chemical vapor deposition, demonstrate rectification to -200 V at room temperature, representing a fourfold improvement in reported 3C-SiC diode blocking voltage. The reverse leakage currents and saturation current densities measured on these diodes also show significant improvement compared to previously reported 3C-SiC <span class="hlt">p-n</span> junction diodes. When placed under sufficient forward bias, the diodes emit significantly bright green-yellow light. These results should lead to substantial advancements in 3C-SiC transistor performance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22089450','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22089450"><span id="translatedtitle">Optical properties of InGa<span class="hlt">PN</span> epilayer with low nitrogen content grown by molecular beam epitaxy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kim, Kang Min; Nonoguchi, Shogo; Krishnamurthy, Daivasigamani; Emura, Shuichi; Hasegawa, Shigehiko; Asahi, Hajime</p> <p>2012-09-15</p> <p>The effect of nitrogen concentration on the optical properties of InGaP(N) epilayer was investigated. The temperature dependence of the photoluminescence (PL) peak energy of InGa<span class="hlt">PN</span> (N = 1%) epilayer around room temperature was found to be almost one-half of that of InGaP epilayer. The incorporation of N causes the reduction of the coupling constant for the electron-phonon interaction, leading to the reduced temperature dependence of the PL peak shift. Thermal activation energy, which is deduced from the Arrhenius plot of PL intensity, was decreased by N incorporation. The reduced PL quenching is discussed in terms of the changes in the band alignment at the InGa<span class="hlt">PN</span>/GaAs heterointerface by the increase in the N concentration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24681301','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24681301"><span id="translatedtitle">Long-term performance and microbial ecology of a two-stage <span class="hlt">PN</span>-ANAMMOX process treating mature landfill leachate.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Li, Huosheng; Zhou, Shaoqi; Ma, Weihao; Huang, Pengfei; Huang, Guotao; Qin, Yujie; Xu, Bin; Ouyang, Hai</p> <p>2014-05-01</p> <p>Long-term performance of a two-stage partial nitritation (<span class="hlt">PN</span>)-anaerobic ammonium oxidation (ANAMMOX) process treating mature landfill leachate was investigated. Stable partial nitritation performance was achieved in a sequencing batch reactor (SBR) using endpoint pH control, providing an effluent with a ratio of NO2(-)-N/NH4(+)-N at 1.23 ± 0.23. High rate nitrogen removal over 4 kg N/m(3)/d was observed in the ANAMMOX reactor in the first three months. However, during long-term operation, the ANAMMOX reactor can only stably operate under nitrogen load of 1 kg N/m(3)/d, with 85 ± 1% of nitrogen removal. The ammonium oxidizing bacteria (AOB) in the <span class="hlt">PN</span>-SBR were mainly affiliated to Nitrosomonas sp. IWT514, Nitrosomonas eutropha and Nitrosomonas eutropha, the anaerobic ammonium oxidizing bacteria (AnAOB) in the ANAMMOX reactor were mainly affiliated to Kuenenia stuttgartiensis. PMID:24681301</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JaJAP..55a2301S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JaJAP..55a2301S"><span id="translatedtitle">Estimation of defect activation energy around <span class="hlt">pn</span> interfaces of Cu(In,Ga)Se2 solar cells using impedance spectroscopy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sakakura, Hidenori; Itagaki, Masayuki; Sugiyama, Mutsumi</p> <p>2016-01-01</p> <p>We investigate the defect activation energy around the <span class="hlt">pn</span> interface of Cu(In,Ga)Se2 (CIGS)-based solar cells using a simple electrochemical impedance spectroscopy. By applying AC and DC voltages to the solar cells, we observed an “inductive” element around the <span class="hlt">pn</span> interface, which is ignored in conventional deep-level transient spectroscopy or admittance spectroscopy. A defect model is evaluated by proposing an equivalent circuit that includes a positive/negative constant phase element (CPE) to represent the area around the CdS/CIGS interface. By fitting the impedance data, the CPE index and CPE constant show a relationship with the defect activation energy or defect concentration. This result is significant because it may help reveal the defect properties of CIGS solar cells or any other semiconductor devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4464396','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4464396"><span id="translatedtitle">Imaging of built-in electric field at a <span class="hlt">p-n</span> junction by scanning transmission electron microscopy</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Shibata, Naoya; Findlay, Scott D.; Sasaki, Hirokazu; Matsumoto, Takao; Sawada, Hidetaka; Kohno, Yuji; Otomo, Shinya; Minato, Ryuichiro; Ikuhara, Yuichi</p> <p>2015-01-01</p> <p>Precise measurement and characterization of electrostatic potential structures and the concomitant electric fields at nanodimensions are essential to understand and control the properties of modern materials and devices. However, directly observing and measuring such local electric field information is still a major challenge in microscopy. Here, differential phase contrast imaging in scanning transmission electron microscopy with segmented type detector is used to image a <span class="hlt">p-n</span> junction in a GaAs compound semiconductor. Differential phase contrast imaging is able to both clearly visualize and quantify the projected, built-in electric field in the <span class="hlt">p-n</span> junction. The technique is further shown capable of sensitively detecting the electric field variations due to dopant concentration steps within both p-type and n-type regions. Through live differential phase contrast imaging, this technique can potentially be used to image the electromagnetic field structure of new materials and devices even under working conditions. PMID:26067359</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22398815','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22398815"><span id="translatedtitle">Determination of some basic physical parameters of SnO based on SnO/Si <span class="hlt">pn</span> heterojunctions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Li, Xiuxia; Liang, Lingyan E-mail: h-cao@nimte.ac.cn; Cao, Hongtao E-mail: h-cao@nimte.ac.cn; Qin, Ruifeng; Zhang, Hongliang; Gao, Junhua; Zhuge, Fei</p> <p>2015-03-30</p> <p>P-SnO/n-Si heterojunctions were constructed by using e-beam evaporation in combination with ultra-violet lithography technique. The current-voltage and capacitance-voltage characteristics of the <span class="hlt">pn</span> heterojunctions were systematically investigated, through which the diode parameters, such as the turn-on voltage, forward-to-reverse current ratio, series resistance, ideality factor, and build-in voltage, were also determined. In particular, the <span class="hlt">pn</span> heterojunctions presented a relatively good electrical rectifying behavior, with a forward-to-reverse current ratio up to 58 ± 5 at ±2.0 V. The relative permittivity and work function of the SnO films were measured to be 18.8 ± 1.7 and 4.3 eV, respectively. The energy band diagram of the heterojunctions was depicted in detail, which can interpret the rectifying behavior very well.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1114092','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1114092"><span id="translatedtitle">Mapping Electrostatic Profiles Across Axial <span class="hlt">p-n</span> Junctions in Si Nanowires using Off-Axis Electron Holography</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gan, Zhaofeng; Perea, Daniel E.; Yoo, Jinkyoung; Picraux, Samuel T.; Smith, David J.; Mccartney, Martha R.</p> <p>2013-10-07</p> <p>Si nanowires (NWs) with axial <span class="hlt">p-n</span> junctions were grown by the vapor-liquid-solid method. Transmission electron microscopy and electron holography were used to characterize the microstructure and electrostatic properties. Measurement of the potential profile showed the presence of a <span class="hlt">p-n</span> junction with a height of 1.0±0.3V. A Schottky barrier was observed at the end of the NW due to the Au catalyst particle. Comparison with simulations indicated dopant concentrations of 1019cm-3 for donors and 1017cm-3 for acceptors. These results confirm the benefit of combining off-axis electron holography with simulations for determining localized information about the electrically active dopant distributions in nanowire structures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ApPhL.103x1114G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ApPhL.103x1114G"><span id="translatedtitle">A silicon-wafer based <span class="hlt">p-n</span> junction solar cell by aluminum-induced recrystallization and doping</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gardelis, S.; Nassiopoulou, A. G.; Manousiadis, P.; Vouroutzis, Î..; Frangis, N.</p> <p>2013-12-01</p> <p>We fabricated a silicon-wafer based <span class="hlt">p-n</span> junction solar cell with conversion efficiency of 11% without conventional doping of the emitter or the use of anti-reflecting coatings. The emitter was originally nanocrystalline, grown on n-type crystalline Si and covered with a thin semi-transparent Al layer. Annealing in nitrogen at 430 °C promoted a simultaneous aluminum (Al)-induced recrystallization and Al-doping of the emitter. The recrystallized emitter consisted of considerably larger Si grains which were epitaxially crystallized on the Si substrate. These two effects led to a considerable improvement of the electrical and photovoltaic properties of the resulting <span class="hlt">p-n</span> junction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001JAP....90.2654R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001JAP....90.2654R"><span id="translatedtitle">Steady-state characteristics of lateral <span class="hlt">p-n</span> junction vertical-cavity surface-emitting lasers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ryzhii, V.; Tsutsui, N.; Khmyrova, I.; Ikegami, T.; Vaccaro, P. O.; Taniyama, H.; Aida, T.</p> <p>2001-09-01</p> <p>We developed an analytical device model for lateral <span class="hlt">p-n</span> junction vertical-cavity surface-emitting lasers (LJVCSELs) with a quantum well active region. The model takes into account the features of the carrier injection, transport, and recombination in LJVCSELs as well as the features of the photon propagation in the cavity. This model is used for the calculation and analysis of the LJVCSEL steady-state characteristics. It is shown that the localization of the injected electrons primarily near the <span class="hlt">p-n</span> junction and the reabsorption of lateral propagating photons significantly effects the LJVCSELs performance, in particular, the LJVCSEL threshold current and power-current characteristics. The reincarnation of electrons and holes due to the reabsorption of lateral propagating photons can substantially decrease the threshold current.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/18500775','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/18500775"><span id="translatedtitle">Characterization of high-<span class="hlt">yield</span> performance as affected by genotype and environment in rice.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Song; Zeng, Fang-rong; Pao, Zong-zhi; Zhang, Guo-ping</p> <p>2008-05-01</p> <p>We characterized <span class="hlt">yield</span>-relevant characters and their variations over genotypes and environments (locations and years) by examining two rice varieties (9746 and Jinfeng) with high <span class="hlt">yield</span> potential. 9746 and Jinfeng were planted in two locations of Shanghai, China, during 2005 and 2006. The results show that there was a large variation in grain <span class="hlt">yield</span> between locations and years. The realization of high <span class="hlt">yield</span> potential for the two types of rice was closely related to the improved sink size, such as more panicles per square meter or grains per panicle. Stem and leaf biomasses were mainly accumulated from tillering stage to heading stage, and showed slow decline during grain filling. Meanwhile, some photosynthetic characters including net photosynthesis rate (<span class="hlt">Pn</span>), leaf area index (LAI), specific leaf area (SLA), fluorescence parameter (maximum quantum <span class="hlt">yield</span> of PSII, Fv/Fm), chlorophyll content (expressed as SPAD value), as well as nutrient (N, P, K) uptake were also measured to determine their variations over genotypes and environments and their relationships with grain <span class="hlt">yield</span>. Although there were significant differences between years or locations for most measurements, SLA at tillering and heading stages, Fv/Fm and LAI at heading stage, stem biomass at heading and maturity stages, and leaf nitrogen concentration at tillering and heading stages remained little changed, indicating their possible applications as selectable characters in breeding programs. It was also found that stem nitrogen accumulation at tillering stage is one of the most important and stable traits for high <span class="hlt">yield</span> formation. PMID:18500775</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19840043241&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DP-n%2Bjunction','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19840043241&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DP-n%2Bjunction"><span id="translatedtitle">Diffused junction <span class="hlt">p(+)-n</span> solar cells in bulk GaAs. II - Device characterization and modelling</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Keeney, R.; Sundaram, L. M. G.; Rode, H.; Bhat, I.; Ghandhi, S. K.; Borrego, J. M.</p> <p>1984-01-01</p> <p>The photovoltaic characteristics of <span class="hlt">p(+)-n</span> junction solar cells fabricated on bulk GaAs by an open tube diffusion technique are presented in detail. Quantum efficiency measurements were analyzed and compared to computer simulations of the cell structure in order to determine material parameters such as diffusion length, surface recombination velocity and junction depth. From the results obtained it is projected that proper optimization of the cell parameters can increase the efficiency of the cells to close to 20 percent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1248808','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1248808"><span id="translatedtitle">Electrocatalytic Reduction of Carbon Dioxide with a Well-Defined <span class="hlt">PN</span> <sup>3</sup> -Ru Pincer Complex</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Min, Shixiong; Rasul, Shahid; Li, Huaifeng; Grills, David C.; Takanabe, Kazuhiro; Li, Lain-Jong; Huang, Kuo-Wei</p> <p>2015-11-13</p> <p>We established a well-defined <span class="hlt">PN</span><sup>3</sup>-Ru pincer complex (5) bearing a redox-active bipyridine ligand with an aminophosphine arm as an effective and stable molecular electrocatalyst for CO<sub>2</sub> reduction to CO and HCOOH with negligible formation of H<sub>2</sub> in a H<sub>2</sub>O/MeCN mixture.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JMP....57b3506D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JMP....57b3506D"><span id="translatedtitle">General solutions of the supersymmetric ℂP2 sigma model and its generalisation to ℂ<span class="hlt">PN</span>-1</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Delisle, L.; Hussin, V.; Zakrzewski, W. J.</p> <p>2016-02-01</p> <p>A new approach for the construction of finite action solutions of the supersymmetric ℂ<span class="hlt">PN</span>-1 sigma model is presented. We show that this approach produces more non-holomorphic solutions than those obtained in previous approaches. We study the ℂP2 model in detail and present its solutions in an explicit form. We also show how to generalise this construction to N > 3.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25938882','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25938882"><span id="translatedtitle">A possible cooperative structural transition of DNA in the 0.25-2.0 <span class="hlt">pN</span> range.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schurr, J Michael</p> <p>2015-05-28</p> <p>The measured effective torsional rigidities of single twisted DNAs under various tensions conflict with theoretical predictions of Moroz and Nelson (MN) at low forces in the 0.25-2.0 <span class="hlt">pN</span> range. However, MN theory was recently shown to agree well with effective torsional rigidities obtained from simulations, indicating that MN theory is valid down to 0.25 <span class="hlt">pN</span> for a filament with a constant intrinsic torsional rigidity. Here MN theory is used with an assumed persistence length, 50 nm, to obtain the force-dependent intrinsic torsional rigidity of the filament at each force from its measured effective torsional rigidity. The resulting values rise ∼1.8-fold with increasing force from 0.25 to 2.0 <span class="hlt">pN</span>. Unexpected behavior of the relative extensions of the untwisted DNAs of Mosconi et al. is noted, and ascribed to a small increase in contour length with force over the 0.18-2.0 <span class="hlt">pN</span> range. The variations of both the intrinsic torsional rigidity and rise per base pair (bp) with force are suggested to arise from a force-induced shift of a cooperative equilibrium between two conformations with different rises per bp. A two-state nearest-neighbor model is formulated, and ranges of optimal parameters are determined by fitting the model to the experimental differences in rise per bp as a function of force. Optimal adjustment of the torsion elastic constants of the two states enables the same optimal model(s) with fixed parameters to provide reasonably good fits of the experimental torsion elastic constant data. The results reconcile single-molecule measurements on DNAs under tension with numerous results from fluorescence polarization anisotropy, topoisomer distributions, X-ray scattering of DNAs with attached gold colloids, and other kinds of measurements. PMID:25938882</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/20982851','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/20982851"><span id="translatedtitle">The influence of electron irradiation on electron holography of focused ion beam milled GaAs <span class="hlt">p-n</span> junctions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cooper, David; Twitchett-Harrison, Alison C.; Midgley, Paul A.; Dunin-Borkowski, Rafal E.</p> <p>2007-05-01</p> <p>Electron beam irradiation is shown to significantly influence phase images recorded from focused ion beam milled GaAs <span class="hlt">p-n</span> junction specimens examined using off-axis electron holography in the transmission electron microscope. Our results show that the use of improved electrical connections to the specimen overcomes this problem, and may allow the correct built in potential across the junction to be recovered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000094024','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000094024"><span id="translatedtitle">Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Performance Verification Report: METSAT (S/N) AMSU-A1 Receiver Assemblies <span class="hlt">P/N</span> 1356429-1 S/N F06 and <span class="hlt">P/N</span> 1356409-1 S/N F06</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1999-01-01</p> <p>This is the Performance Verification Report, METSAT (S/N 109) AMSU-A1 Receiver Assemblies, <span class="hlt">P/N</span> 1356429-1 S/N F06 and <span class="hlt">P/N</span> 1356409 S/N F06, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/750189','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/750189"><span id="translatedtitle">AlGaAs/InGaAsN/GaAs <span class="hlt">Pn</span>P double heterojunction bipolar transistor</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chang, P.C.; Baca, A.G.; Li, N.Y.; Sharps, P.R.; Hou, H.Q.; Laroche, J.R.; Ren, F.</p> <p>2000-01-04</p> <p>The authors demonstrated a functional <span class="hlt">Pn</span>P double heterojunction bipolar transistor (DHBT) using AlGaAs, InGaAsN, and GaAs. The band alignment between InGaAsN and GaAs has a large {triangle}E{sub c} and negligible {triangle}E{sub v}, this unique characteristic is very suitable for <span class="hlt">Pn</span>P DHBT applications. The metalorganic vapor phase epitaxy (MOCVD) grown Al{sub 0.3}Ga{sub 0.7}As/In{sub 0.03}Ga{sub 0.97}As{sub 0.99}N{sub 0.01}/GaAs <span class="hlt">Pn</span>P DHBT is lattice matched to GaAs and has a peak current gain of 25. Because of the smaller bandgap (E{sub g}=1.20eV) of In{sub 0.03}Ga{sub 0.97}As{sub 0.99}N{sub 0.01} used for the base layer, this device has a low V{sub ON} of 0.79 V, which is 0.25 V lower than in a comparable Pnp AlGaAs/GaAs HBT. And because GaAs is used for the collector, its BV{sub CEO} is 12 V, consistent with BV{sub CEO} of AlGaAs/GaAs HBTs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ApSS..258.6169L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ApSS..258.6169L"><span id="translatedtitle">Morphology-tunable assembly of periodically aligned Si nanowire and radial <span class="hlt">pn</span> junction arrays for solar cell applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Xiaocheng; Liang, Kun; Tay, Beng Kang; Teo, Edwin H. T.</p> <p>2012-06-01</p> <p>Large-area periodically aligned Si nanowire (PASiNW) arrays have been fabricated on Si substrates via a templated catalytic chemical etching process. The diameter, length, packing density, and even the shape of Si nanowires (SiNWs) could be precisely controlled and tuned. A local coupling redox mechanism involving the reduction of H2O2 on silver particles and the dissolution of Si is responsible for formation of SiNWs. With the as-prepared SiNWs as templates, three kinds of PASiNW radial <span class="hlt">pn</span> junction structures were fabricated on Si substrates via a solid-state phosphorous diffusion strategy and their applications in solar cells were also explored. The PASiNW radial <span class="hlt">pn</span> junction-based solar cell with big diameter and interspace shows the highest power conversion efficiency (PCE) of 4.10% among the three kinds of devices. Further optimization, including surface passivation and electrode contact, is still needed for the higher efficiency PASiNW radial <span class="hlt">pn</span> junction-based solar cells in the future.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25157588','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25157588"><span id="translatedtitle">Electroluminescence and photocurrent generation from atomically sharp WSe2/MoS2 heterojunction <span class="hlt">p-n</span> diodes.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cheng, Rui; Li, Dehui; Zhou, Hailong; Wang, Chen; Yin, Anxiang; Jiang, Shan; Liu, Yuan; Chen, Yu; Huang, Yu; Duan, Xiangfeng</p> <p>2014-10-01</p> <p>The <span class="hlt">p-n</span> diodes represent the most fundamental device building blocks for diverse optoelectronic functions, but are difficult to achieve in atomically thin transition metal dichalcogenides (TMDs) due to the challenges in selectively doping them into p- or n-type semiconductors. Here, we demonstrate that an atomically thin and sharp heterojunction <span class="hlt">p-n</span> diode can be created by vertically stacking p-type monolayer tungsten diselenide (WSe2) and n-type few-layer molybdenum disulfide (MoS2). Electrical measurements of the vertically staked WSe2/MoS2 heterojunctions reveal excellent current rectification behavior with an ideality factor of 1.2. Photocurrent mapping shows rapid photoresponse over the entire overlapping region with a highest external quantum efficiency up to 12%. Electroluminescence studies show prominent band edge excitonic emission and strikingly enhanced hot-electron luminescence. A systematic investigation shows distinct layer-number dependent emission characteristics and reveals important insight about the origin of hot-electron luminescence and the nature of electron-orbital interaction in TMDs. We believe that these atomically thin heterojunction <span class="hlt">p-n</span> diodes represent an interesting system for probing the fundamental electro-optical properties in TMDs and can open up a new pathway to novel optoelectronic devices such as atomically thin photodetectors, photovoltaics, as well as spin- and valley-polarized light emitting diodes, on-chip lasers. PMID:25157588</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27579778','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27579778"><span id="translatedtitle">Polymer Light-Emitting Electrochemical Cells:  In Situ Formation of a Light-Emitting <span class="hlt">p-n</span> Junction.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pei, Q; Yang, Y; Yu, G; Zhang, C; Heeger, A J</p> <p>1996-04-24</p> <p>Solid-state polymer light-emitting electrochemical cells have been fabricated using thin films of blends of poly(1,4-phenylenevinylene) and poly(ethylene oxide) complexed with lithium trifluoromethanesulfonate. The cells contain three layers:  the polymer film (as the emissive layer) and indium-tin oxide and aluminum films as the two contact electrodes. When externally biased, the conjugated polymers are p-doped and n-doped on opposite sides of the polymer layer, and a light-emitting <span class="hlt">p-n</span> junction is formed in between. The admixed polymer electrolyte provides the counterions and the ionic conductivity necessary for doping. The <span class="hlt">p-n</span> junction is dynamic and reversible, with an internal built-in potential close to the band gap of the redox-active conjugated polymer (2.4 eV for PPV). Green light emitted from the <span class="hlt">p-n</span> junction was observed with a turn-on voltage of about 2.4 V. The devices reached 8 cd/m(2) at 3 V and 100 cd/m(2) at 4 V, with an external quantum efficiency of 0.3-0.4% photons/electron. The response speed of these cells was around 1 s, depending on the diffusion of ions. Once the light-emitting junction had been formed, the subsequent operation had fast response (microsecond scale or faster) and was no longer diffusion-controlled. PMID:27579778</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27518150','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27518150"><span id="translatedtitle">Direct assessment of <span class="hlt">p-n</span> junctions in single GaN nanowires by Kelvin probe force microscopy.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Minj, Albert; Cros, Ana; Auzelle, Thomas; Pernot, Julien; Daudin, Bruno</p> <p>2016-09-23</p> <p>Making use of Kelvin probe force microscopy, in dark and under ultraviolet illumination, we study the characteristics of <span class="hlt">p-n</span> junctions formed along the axis of self-organized GaN nanowires (NWs). We map the contact potential difference of the single NW <span class="hlt">p-n</span> junctions to locate the space charge region and directly measure the depletion width and the junction voltage. Simulations indicate a shrinkage of the built-in potential for NWs with small diameter due to surface band bending, in qualitative agreement with the measurements. The photovoltage of the NW/substrate contact is studied by analyzing the response of NW segments with p- and n-type doping under illumination. Our results show that the shifts of the Fermi levels, and not the changes in surface band bending, are the most important effects under above band-gap illumination. The quantitative electrical information obtained here is important for the use of NW <span class="hlt">p-n</span> junctions as photovoltaic or rectifying devices at the nanoscale, and is especially relevant since the technique does not require the formation of ohmic contacts to the NW junction. PMID:27518150</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4136977','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4136977"><span id="translatedtitle">A Multi-institutional Investigation of the Prognostic Value of Lymph Nodal <span class="hlt">Yield</span> in Advanced Stage Oral Cavity Squamous Cell Carcinoma (OCSCC)</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Jaber, James J.; Zender, Chad A.; Mehta, Vikas; Davis, Kara; Ferris, Robert L.; Lavertu, Pierre; Rezaee, Rod; Feustel, Paul J.</p> <p>2014-01-01</p> <p>Background Although existing literature provides surgical recommendations for treating occult disease (cN0) in early stage oral cavity squamous cell carcinoma, a focus on late stage OCSCC is less pervasive. Methods The records of 162 late stage OCSCC <span class="hlt">pN</span>0 individuals that underwent primary neck dissections were reviewed. Lymph node <span class="hlt">yield</span> (LNY) as a prognosticator was examined. Results Despite being staged <span class="hlt">pN</span>0, patients that had a higher LNY had an improved regional/distant control rates, DFS, DSS, and OS. LNY consistently outperformed all other standard variables as being the single best prognostic factor with a tight risk ratio range (RR = 0.95–0.98) even when correcting for the number of lymph nodes examined. Conclusion The results of this study showed that lower regional recurrence rates and improved survival outcomes were seen as lymph node <span class="hlt">yield</span> increased for advanced T-stage OCSCC <span class="hlt">pN</span>0. This suggests that increasing lymph node <span class="hlt">yield</span> with an extended cervical lymphadenectomy may result in lower recurrence rates and improved survival outcomes for this advanced stage group. PMID:24038739</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005PhLB..610...31A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005PhLB..610...31A"><span id="translatedtitle">Detailed comparison of the pp →π+ <span class="hlt">pn</span> and pp →π+ d reactions at 951 MeV</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abdel-Bary, M.; Budzanowski, A.; Chatterjee, A.; Ernst, J.; Hawranek, P.; Hinterberger, F.; Jha, V.; Kilian, K.; Kliczewski, S.; Kirillov, D.; Kolev, D.; Kravcikova, M.; Kutsarova, T.; Lesiak, M.; Lieb, J.; Machner, H.; Magiera, A.; Maier, R.; Martinska, G.; Nedev, S.; Niskanen, J.; Piskunov, N.; Prasuhn, D.; Protić, D.; von Rossen, P.; Roy, B. J.; Sitnik, I.; Siudak, R.; Smiechowicz, M.; Tsenov, R.; Ulicny, M.; Urban, J.; Vankova, G.; Wilkin, C.; GEM Collaboration</p> <p>2005-03-01</p> <p>The positively charged pions produced in proton-proton collisions at a beam momentum of 1640 MeV/c were measured in the forward direction with a high resolution magnetic spectrograph. The missing mass distribution shows the bound state (deuteron) clearly separated from the <span class="hlt">pn</span> continuum. Despite the very good resolution, there is no evidence for any significant production of the <span class="hlt">pn</span> system in the spin-singlet state. However, the σ (pp →π+ <span class="hlt">pn</span>) / σ (pp →π+ d) cross section ratio is about twice as large as that predicted from S-wave final-state-interaction theory and it is suggested that this is due to D-state effects in the <span class="hlt">pn</span> system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000034236','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000034236"><span id="translatedtitle">Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Performance Verification Report: Antenna Drive Subsystem METSAT AMSU-A2 (<span class="hlt">PN</span>:1331200-2, SN:108)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Haapala, C.</p> <p>1999-01-01</p> <p>This is the Performance Verification Report, Antenna Drive Subassembly, Antenna Drive Subsystem, METSAT AMSU-A2 (<span class="hlt">P/N</span> 1331200-2, SN: 108), for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21347244','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21347244"><span id="translatedtitle">Electrical properties of C-doped p-type GaP and Ga<span class="hlt">PN</span> grown by molecular beam epitaxy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Liu Zhengxin; Kawanami, Hitoshi; Sakata, Isao</p> <p>2010-01-18</p> <p>The electrical properties of C-doped p-type GaP and Ga<span class="hlt">PN</span> epilayers grown by molecular beam epitaxy using CBr{sub 4} as a doping source have been investigated. C is shown to be a relatively shallow acceptor both in GaP and Ga<span class="hlt">PN</span>, with the activation energy in the regions of 16-33 and 18-35 meV, respectively. GaP demonstrates ordinary conduction characteristics, whereas Ga<span class="hlt">PN</span> has a typical mixed conduction effect and the impurity conduction becomes dominant at low temperatures. It is conjectured that impurity conduction and ionized impurity scattering mechanisms in Ga<span class="hlt">PN</span> may be related to the inactivated C and N radicals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19980002830','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19980002830"><span id="translatedtitle">Electrical and Optical Performance Characteristics of <span class="hlt">p/n</span> InGaAs Monolithic Interconnected Modules</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wilt, David M.; Fatemi, Navid S.; Jenkins, Phillip P.; Weizer, Victor G.; Hoffman, Richard W., Jr.; Murray, Christopher S.; Riley, David R.</p> <p>1997-01-01</p> <p>There has been a traditional trade-off in ThermoPhotoVoltaic (TPV) energy conversion development between system efficiency and power density. This trade-off originates from the use of front surface spectral controls such as selective emitters and various types of filters. A Monolithic Interconnected Module (MIM) structure has been developed which allows for both high power densities and high system efficiencies. The MIM device consists of many individual Indium Gallium Arsenide (InGaAs) devices series-connected on a single semi-insulating Indium Phosphide (InP) substrate. The MIMs are exposed to the entire emitter output, thereby maximizing output power density. An InfraRed (IR) reflector placed on the rear surface of the substrate returns the unused portion of the emitter output spectrum back to the emitter for recycling, thereby providing for high system efficiencies. Initial MIM development has focused on a 1 sq cm device consisting of eight (8) series interconnected cells. MIM devices, produced from 0.74eV InGaAs, have demonstrated V(sub infinity) = 3.2 volts, J(sub sc) = 70 mA/sq cm and a fill factor of 66% under flashlamp testing. IR reflectance measurements (greater than 2 microns) of these devices indicate a reflectivity of greater than 82%. MIM devices produced from 0.55 eV InGaAs have also been demonstrated. In addition, conventional <span class="hlt">p/n</span> InGaAs devices with record efficiencies (11.7% AM0) have been demonstrated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1236353','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1236353"><span id="translatedtitle">The secretory granule matrix-electrolyte interface: a homologue of the <span class="hlt">p-n</span> rectifying junction.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Marszalek, P E; Markin, V S; Tanaka, T; Kawaguchi, H; Fernandez, J M</p> <p>1995-01-01</p> <p>When placed at the tip of a glass micropipette electrode the polymeric matrix of the secretory granule behaves like a diode. The measured current was 100-fold greater at negative potentials compared to positive potentials, and up to sixfold greater than that measured with the pipette alone. By manipulating the geometry of the electric field we show that these electrical properties result from focusing an electric field at the gel-electrolyte interface. We also show, by using pulsed-laser imaging with fluorescein as the ionic probe, that there is a rapid accumulation and depletion of ions at the gel-electrolyte interface. A voltage pulse of -9 V applied to the gel caused a severalfold increase in the fluorescence intensity within 5 ms. This correlated with an increase in the measured current (approximately 1 microA). In contrast, within 5 ms of applying +9 V we recorded a decrease in the fluorescence intensity, which paralleled the twofold decrease in the measured current. This is similar to a <span class="hlt">p-n</span> junction where an applied voltage causes the accumulation and depletion of charge carriers. Using synthetic gels (diameter 3-6 microns) with different charge characteristics we observed no rectification of the current with neutral gels and confirmed that rectification and amplification of the current were dependent on the fixed charge within a gel. In addition, we modeled the conduction at the gel-electrolyte interface using the Nernst-Planck electrodiffusion equation and accurately fitted the experimental current-voltage relationships. This study provides some insight into how biological interfaces may function. For example, we suggest that neurotransmitter release during exocytosis could be regulated by voltage-induced accumulation and depletion of ions at the interface between the secretory granule and the fusion pore. Images FIGURE 1 FIGURE 7 FIGURE 8 FIGURE 9 PMID:8534793</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20000032819&hterms=photovoltaic+cell+applications&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dphotovoltaic%2Bcell%2Bapplications','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20000032819&hterms=photovoltaic+cell+applications&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dphotovoltaic%2Bcell%2Bapplications"><span id="translatedtitle">Status of Diffused Junction <span class="hlt">p(+)n</span> InP Solar Cells for Space Applications</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Faur, Mircea; Faur, Maria; Flood, D. J.; Brinker, D. J.; Goradia, C.; Fatemi, N. S.; Jenkins, P. P.; Wilt, D. M.; Bailey, S.</p> <p>1994-01-01</p> <p>Recently, we have succeeded in fabricating diffused junction p(+)n(Cd,S) InP solar cells with measured AMO, 25 C open circuit voltage (V(sub OC)) of 887.6 mV, which, to the best of our knowledge, is higher than previously reported V(sub OC) values for any InP homojunction solar cells. The experiment-based projected achievable efficiency of these cells using LEC grown substrates is 21.3%. The maximum AMO, 25 C efficiency recorded to date on bare cells is, however, only 13.2%. This is because of large external and internal losses due to non-optimized front grid design, antireflection (AR) coating and emitter thickness. This paper summarizes recent advances in the technology of fabrication of <span class="hlt">p(+)n</span> InP diffused structures and solar cells, resulted from a study undertaken in an effort to increase the cell efficiency. The topics discussed in this paper include advances in: 1) the formation of thin p(+) InP:Cd emitter layers, 2) electroplated front contacts, 3) surface passivation and 4) the design of a new native oxide/AI203/MgF2 three layer AR coating using a chemically-grown P-rich passivating oxide as a first layer. Based on the high radiation resistance and the excellent post-irradiation annealing and recovery demonstrated in the early tests done to date, as well as the projected high efficiency and low-cost high-volume fabricability, these cells show a very good potential for space photovoltaic applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApSS..365..209Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApSS..365..209Z"><span id="translatedtitle">Fabrication of BiOBr nanosheets@TiO2 nanobelts <span class="hlt">p-n</span> junction photocatalysts for enhanced visible-light activity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Yang; Huang, Xiang; Tan, Xin; Yu, Tao; Li, Xiangli; Yang, Libin; Wang, Shucong</p> <p>2016-03-01</p> <p>The construction of <span class="hlt">p-n</span> junction structure is a smart strategy for improving the photocatalytic activity, since <span class="hlt">p-n</span> junctions can inhibit the recombination of photo-induced charges. Herein, BiOBr nanosheets@TiO2 nanobelts <span class="hlt">p-n</span> junction photocatalysts were prepared by assembling BiOBr nanosheets on the surface of TiO2 nanobelts via a hydrothermal route followed by a co-precipitation process. BiOBr@TiO2 <span class="hlt">p-n</span> junction photocatalysts exhibited enhanced photocatalytic activity in photocatalytic H2 production over water splitting and photodegradation of Rhodamine B (RhB) under visible light irradiation. Mott-Schottky plots confirmed the formation of <span class="hlt">p-n</span> junctions in the interface of BiOBr and TiO2. The enhanced photocatalytic performance can be ascribed to the 1D nanostructure and the formation of <span class="hlt">p-n</span> junctions. This work shows a potential application of low cost BiOBr as a substitute for noble metals in photocatalytic H2 production under visible light irradiation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016SSSci..56...45J&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016SSSci..56...45J&link_type=ABSTRACT"><span id="translatedtitle">The coating of conducting copolymer on coordination polymer nanorod: A visible light active <span class="hlt">p-n</span> heterojunction photocatalyst for H2 production</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jia, Yuan; Mei, Ming-liang; Xu, Xin-xin; Wang, Lin-shan</p> <p>2016-06-01</p> <p>A visible light active <span class="hlt">p-n</span> heterojunction photocatalyst was synthesized successfully through in-situ chemical oxidation copolymerization of aniline (ANI) and diphenylamine-4-sulfonate (DPAS) with the existence of coordination polymer nanorod (CPNR) under initiation of ammonium persulfate (APS). Compared with neat coordination polymer nanorod, the resulted <span class="hlt">p-n</span> heterojunction photocatalyst exhibits higher H2 generationrate under visible light irradiation. In this heterojunction photocatalyst, as a p-type semiconductor possessing suitable energy levels with coordination polymer nanorod, poly-(aniline-co-N-(4-sulfophenyl)-aniline) (PAPSA) forms <span class="hlt">p-n</span> heterojunction with n-type coordination polymer nanorod, the inner electric field of <span class="hlt">p-n</span> heterojunction accelerates the separation of electrons and holes, which enhances H2 production performance. Furthermore, the influence of concentration ratio between DPAS and ANI on photocatalytic property of the <span class="hlt">p-n</span> heterojunction photocatalyst was discussed and a reasonable condition to fabricate photocatalyst with high H2 generationrate had been obtained. During photocatalytic water splitting H2 generation, the <span class="hlt">p-n</span> heterojunction photocatalyst exhibited outstanding stability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998SPIE.3301...27V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998SPIE.3301...27V"><span id="translatedtitle">6 x 6-cm fully depleted <span class="hlt">pn</span>-junction CCD for high-resolution spectroscopy in the 0.1- to 15-keV photon energy range</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>von Zanthier, Christoph; Holl, Peter; Kemmer, Josef; Lechner, Peter; Maier, B.; Soltau, Heike; Stoetter, R.; Braeuninger, Heinrich W.; Dennerl, Konrad; Haberl, Frank; Hartmann, R.; Hartner, Gisela D.; Hippmann, H.; Kastelic, E.; Kink, W.; Krause, N.; Meidinger, Norbert; Metzner, G.; Pfeffermann, Elmar; Popp, M.; Reppin, Claus; Stoetter, Diana; Strueder, Lothar; Truemper, Joachim; Weber, U.; Carathanassis, D.; Engelhard, S.; Gebhart, Th.; Hauff, D.; Lutz, G.; Richter, R. H.; Seitz, H.; Solc, P.; Bihler, Edgar; Boettcher, H.; Kendziorra, Eckhard; Kraemer, J.; Pflueger, Bernhard; Staubert, Ruediger</p> <p>1998-04-01</p> <p>The concept and performance of the fully depleted <span class="hlt">pn</span>- junction CCD system, developed for the European XMM- and the German ABRIXAS-satellite missions for soft x-ray imaging and spectroscopy in the 0.1 keV to 15 keV photon range, is presented. The 58 mm X 60 mm large <span class="hlt">pn</span>-CCD array uses <span class="hlt">pn</span>- junctions for registers and for the backside instead of MOS registers. This concept naturally allows to fully deplete the detector volume to make it an efficient detector to photons with energies up to 15 keV. For high detection efficiency in the soft x-ray region down to 100 eV, an ultrathin <span class="hlt">pn</span>-CCD backside deadlayer has been realized. Each <span class="hlt">pn</span>-CCD-channel is equipped with an on-chip JFET amplifier which, in combination with the CAMEX-amplifier and multiplexing chip, facilitates parallel readout with a pixel read rate of 3 MHz and an electronic noise floor of ENC < e-. With the complete parallel readout, very fast <span class="hlt">pn</span>-CCD readout modi can be implemented in the system which allow for high resolution photon spectroscopy of even the brightest x-ray sources in the sky.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26915189','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26915189"><span id="translatedtitle">[Effects of potato/soybean intercropping on photosynthetic characteristics and <span class="hlt">yield</span> of three soybean varieties].</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Guang-rong; Yang, Wen-yu; Zhang, Guo-hong; Wang, Li-ming; Yang, Ru-ping; Yong, Tai-wen; Liu, Wei-guo</p> <p>2015-11-01</p> <p>The potato/soybean intercropping trials using three soybean varieties including Zhonghuang 30 (early-maturing variety) , Jidou 17 (mid maturing variety) and Qihuang 34 (late maturing variety) with the sole cropping potato as control were carried out to determine the dynamic changes of leaf area index (LAI) of soybean, accumulation of dry matter, photosynthetic characteristics, <span class="hlt">yield</span> and <span class="hlt">yield</span> components. The results showed that the LAI, dry matter accumulation, net photosynthesis (<span class="hlt">Pn</span>), transpiration rate (Tr) and stomatal conduction (g(s)) of soybean in all intercropping systems were lower than in monoculture because of the influence of intensified lower light during earlier growing stage, and the duration from planting to flowering was extended. When the potato was harvested, the LAI, dry matter accumulation, <span class="hlt">Pn</span>, Tr and g(s) of soybean in all intercropping systems increased, especially for mid-maturing and late-maturing varieties, which became much closer to those in the monoculture. Compared with sole cropping, the pods per plant, seeds per plant and seeds per pod in intercropping system significantly decreased by 22.0%, 36.0% and 17.6% for early-maturing soybean, 5.1%, 13.1% and 8.9% for mid-maturing soybean, 5.7%, 7.6% and 2.1% for late-maturing soybean, respectively. The <span class="hlt">yields</span> of mid-maturing and late-maturing varieties in intercropping systems were higher than that of the early-maturing, which increased by 92.4% and 163.4%, with the land equivalent ratio (LER) of 1.81 and 1.84, respectively. This suggested that mid-maturing and late-maturing soybean varieties were suitable for intercropping with the potato to improve photosynthetic efficiency, dry matter accumulation and <span class="hlt">yield</span> of intercropping soybean. PMID:26915189</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015AGUFM.B43A0540G&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015AGUFM.B43A0540G&link_type=ABSTRACT"><span id="translatedtitle">Incorporating phenology into <span class="hlt">yield</span> models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gray, J. M.; Friedl, M. A.</p> <p>2015-12-01</p> <p>Because the <span class="hlt">yields</span> of many crops are sensitive to meteorological forcing during specific growth stages, phenological information has potential utility in <span class="hlt">yield</span> mapping and forecasting exercises. However, most attempts to explain the spatiotemporal variability in crop <span class="hlt">yields</span> with weather data have relied on growth stage definitions that do not change from year-to-year, even though planting, maturity, and harvesting dates show significant interannual variability. We tested the hypothesis that quantifying temperature exposures over dynamically determined growth stages would better explain observed spatiotemporal variability in crop <span class="hlt">yields</span> than statically defined time periods. Specifically, we used National Agricultural and Statistics Service (NASS) crop progress data to identify the timing of the start of the maize reproductive growth stage ("silking"), and examined the correlation between county-scale <span class="hlt">yield</span> anomalies and temperature exposures during either the annual or long-term average silking period. Consistent with our hypothesis and physical understanding, <span class="hlt">yield</span> anomalies were more correlated with temperature exposures during the actual, rather than the long-term average, silking period. Nevertheless, temperature exposures alone explained a relatively low proportion of the <span class="hlt">yield</span> variability, indicating that other factors and/or time periods are also important. We next investigated the potential of using remotely sensed land surface phenology instead of NASS progress data to retrieve crop growth stages, but encountered challenges related to crop type mapping and subpixel crop heterogeneity. Here, we discuss the potential of overcoming these challenges and the general utility of remotely sensed land surface phenology in crop <span class="hlt">yield</span> mapping.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/14560584','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/14560584"><span id="translatedtitle">Rx for low cash <span class="hlt">yields</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tobe, Chris</p> <p>2003-10-01</p> <p>Certain strategies can offer not-for-profit hospitals potentially greater investment <span class="hlt">yields</span> while maintaining stability and principal safety. Treasury inflation-indexed securities can offer good returns, low volatility, and inflation protection. "Enhanced cash" strategies offer liquidity and help to preserve capital. Stable value "wrappers" allow hospitals to pursue higher-<span class="hlt">yielding</span> fixed-income securities without an increase in volatility. PMID:14560584</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840013854','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840013854"><span id="translatedtitle">Brazil soybean <span class="hlt">yield</span> covariance model</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Callis, S. L.; Sakamoto, C.</p> <p>1984-01-01</p> <p>A model based on multiple regression was developed to estimate soybean <span class="hlt">yields</span> for the seven soybean-growing states of Brazil. The meteorological data of these seven states were pooled and the years 1975 to 1980 were used to model since there was no technological trend in the <span class="hlt">yields</span> during these years. Predictor variables were derived from monthly total precipitation and monthly average temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950014123','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950014123"><span id="translatedtitle"><span class="hlt">P/N</span> In(Al) GaAs multijunction laser power converters</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wojtczuk, Steven; Parados, Themis; Walker, Gilbert</p> <p>1994-01-01</p> <p>Eight In(AI)GaAs <span class="hlt">PN</span> junctions grown epitaxially on the semi-insulating wafer were monolithically integrated in series to boost the approximately 0.4V photovoltage per typical In(Al)GaAs junction to over 3 volts for the 1 sq cm laser power converted (LPC) chip. Advantages of multijunction LCP designs include the need for less circuitry for power reconditioning and the potential for lower I(sup 2)R power loss. As an example, these LPC's have a responsivity of approximately 1 amp/watt. With a single junction LPC, 100 watts/sq cm incident power would lead to about 100 A/sq cm short-circuit current at approximately 0.4V open-cicuit voltage. One disadvantage is the large current would lead to a large I(sup 2)R loss which would lower the fill factor so that 40 watts/sq cm output would not be obtained. Another is that few circuits are designed to work at 0.4 volts, so DC-DC power conversion circuitry would be necessary to raise the voltage to a reasonable level. The multijunction LPC being developed in this program is a step toward solving these problems. In the above example, an eight-junction LPC would have eight times the voltage, approximately 3V, so that DC-DC power conversion may not be needed in many instances. In addition, the multijunction LPC would have 1/8 the current of a single-junction LPC, for only 1/64 the I(sup 2)R loss if the series resistance is the same. Working monolithic multijunction laser power converters (LPC's) were made in two different compositions of the In(x)Al(y)Ga(1-x-y)As semiconductor alloy, In(0.53)Ga(0.47)As (0.74 eV) and In(0.5)Al(0.1)Ga(0.4)As (0.87 eV). The final 0.8 sq cm LPC's had output voltages of about 3 volts and output currents up to about one-half amp. Maximum 1.3 micron power conversion efficiencies were approximately 22 percent. One key advantage of multijunction LPC's is that they have higher output voltages, so that less DC-DC power conversion circuitry is needed in applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/36445','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/36445"><span id="translatedtitle"><span class="hlt">P/N</span> In(Al) GaAs multijunction laser power converters</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wojtczuk, S.; Parados, T.; Walker, G.</p> <p>1994-09-01</p> <p>Eight In(AI)GaAs <span class="hlt">PN</span> junctions grown epitaxially on the semi-insulating wafer were monolithically integrated in series to boost the approximately 0.4V photovoltage per typical In(Al)GaAs junction to over 3 volts for the 1 sq cm laser power converted (LPC) chip. Advantages of multijunction LCP designs include the need for less circuitry for power reconditioning and the potential for lower I(sup 2)R power loss. As an example, these LPC`s have a responsivity of approximately 1 amp/watt. With a single junction LPC, 100 watts/sq cm incident power would lead to about 100 A/sq cm short-circuit current at approximately 0.4V open-cicuit voltage. One disadvantage is the large current would lead to a large I(sup 2)R loss which would lower the fill factor so that 40 watts/sq cm output would not be obtained. Another is that few circuits are designed to work at 0.4 volts, so DC-DC power conversion circuitry would be necessary to raise the voltage to a reasonable level. The multijunction LPC being developed in this program is a step toward solving these problems. In the above example, an eight-junction LPC would have eight times the voltage, approximately 3V, so that DC-DC power conversion may not be needed in many instances. In addition, the multijunction LPC would have 1/8 the current of a single-junction LPC, for only 1/64 the I(sup 2)R loss if the series resistance is the same. Working monolithic multijunction laser power converters (LPC`s) were made in two different compositions of the In(x)Al(y)Ga(1-x-y)As semiconductor alloy, In(0.53)Ga(0.47)As (0.74 eV) and In(0.5)Al(0.1)Ga(0.4)As (0.87 eV). The final 0.8 sq cm LPC`s had output voltages of about 3 volts and output currents up to about one-half amp. Maximum 1.3 micron power conversion efficiencies were approximately 22 percent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Nanos...711182P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Nanos...711182P"><span id="translatedtitle">Nanostructured p-type CZTS thin films prepared by a facile solution process for 3D <span class="hlt">p-n</span> junction solar cells</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Park, Si-Nae; Sung, Shi-Joon; Sim, Jun-Hyoung; Yang, Kee-Jeong; Hwang, Dae-Kue; Kim, Junho; Kim, Gee Yeong; Jo, William; Kim, Dae-Hwan; Kang, Jin-Kyu</p> <p>2015-06-01</p> <p>Nanoporous p-type semiconductor thin films prepared by a simple solution-based process with appropriate thermal treatment and three-dimensional (3D) <span class="hlt">p-n</span> junction solar cells fabricated by depositing n-type semiconductor layers onto the nanoporous p-type thin films show considerable photovoltaic performance compared with conventional thin film <span class="hlt">p-n</span> junction solar cells. Spin-coated p-type Cu2ZnSnS4 (CZTS) thin films prepared using metal chlorides and thiourea show unique nanoporous thin film morphology, which is composed of a cluster of CZTS nanograins of 50-500 nm, and the obvious 3D <span class="hlt">p-n</span> junction structure is fabricated by the deposition of n-type CdS on the nanoporous CZTS thin films by chemical bath deposition. The photovoltaic properties of 3D <span class="hlt">p-n</span> junction CZTS solar cells are predominantly affected by the scale of CZTS nanograins, which is easily controlled by the sulfurization temperature of CZTS precursor films. The scale of CZTS nanograins determines the minority carrier transportation within the 3D <span class="hlt">p-n</span> junction between CZTS and CdS, which are closely related with the photocurrent of series resistance of 3D <span class="hlt">p-n</span> junction solar cells. 3D <span class="hlt">p-n</span> junction CZTS solar cells with nanograins below 100 nm show power conversion efficiency of 5.02%, which is comparable with conventional CZTS thin film solar cells.Nanoporous p-type semiconductor thin films prepared by a simple solution-based process with appropriate thermal treatment and three-dimensional (3D) <span class="hlt">p-n</span> junction solar cells fabricated by depositing n-type semiconductor layers onto the nanoporous p-type thin films show considerable photovoltaic performance compared with conventional thin film <span class="hlt">p-n</span> junction solar cells. Spin-coated p-type Cu2ZnSnS4 (CZTS) thin films prepared using metal chlorides and thiourea show unique nanoporous thin film morphology, which is composed of a cluster of CZTS nanograins of 50-500 nm, and the obvious 3D <span class="hlt">p-n</span> junction structure is fabricated by the deposition of n-type CdS on the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20000033719&hterms=cell+structure&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcell%2Bstructure','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20000033719&hterms=cell+structure&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcell%2Bstructure"><span id="translatedtitle">Hydrogen Passivation of N(+)P and <span class="hlt">P(+)N</span> Heteroepitaxial InP Solar Cell Structures</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chatterjee, B.; Davis, W. C.; Ringel, S. A.; Hoffman, R., Jr.</p> <p>1995-01-01</p> <p>Dislocations and related point defect complexes caused by lattice mismatch currently limit the performance of heteroepitaxial InP cells by introducing shunting paths across the active junction and by the formation of deep traps within the base region. We have previously demonstrated that plasma hydrogenation is an effective and stable means to passivate the electrical activity of such defects in specially designed heteroepitaxial InP test structures to probe hydrogen passivation at typical base depths within a cell structure. In this work, we present our results on the hydrogen passivation of actual heteroepitaxial n(+)p and <span class="hlt">p(+)n</span> InP cell structures grown on GaAs substrates by metalorganic chemical vapor deposition (MOCVD). We have found that a 2 hour exposure to a 13.56 MHz hydrogen plasma at 275 C reduces the deep level concentration in the base regions of both n(+)p and <span class="hlt">p(+)n</span> heteroepitaxial InP cell structures from as-grown values of 5 - 7 x 10(exp 14)/cc, down to 3 - 5 x 10(exp 12)/cc. All dopants were successfully reactivated by a 400 C, 5 minute anneal With no detectable activation of deep levels. I-V analysis indicated a subsequent approx. 100 fold decrease In reverse leakage current at -1 volt reverse bias, and an improved built in voltage for the <span class="hlt">p(+)n</span> structures. ln addition to being passivated,dislocations are also shown to participate in secondary interactions during hydrogenation. We find that the presence of dislocations enhances hydrogen diffusion into the cell structure, and lowers the apparent dissociation energy of Zn-H complexes from 1.19 eV for homoepitaxial Zn-doped InP to 1.12 eV for heteroepitaxial Zn-doped InP. This is explained by additional hydrogen trapping at dislocations subsequent to the reactivation of Zn dopants after hydrogenation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19960045582&hterms=cell+structure&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcell%2Bstructure','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19960045582&hterms=cell+structure&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcell%2Bstructure"><span id="translatedtitle">Hydrogen passivation of N(+)-P and <span class="hlt">P(+)-N</span> heteroepitaxial InP solar cell structures</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chatterjee, Basab; Davis, William C.; Ringel, Steve A.; Hoffman, Richard, Jr.</p> <p>1996-01-01</p> <p>Dislocations and related point defect complexes caused by lattice mismatch currently limit the performance of heteroepitaxial InP cells by introducing shunting paths across the active junction and by the formation of deep traps within the base region. We have previously demonstrated that plasma hydrogenation is an effective and stable means to passivate the electrical activity of such defects in specially designed heteroepitaxial InP test structures to probe hydrogen passivation at typical base depths within a cell structure. In this work, we present our results on the hydrogen passivation of actual heteroepitaxial n-p and <span class="hlt">p-n</span> InP cell structures grown on GaAs substrates by metalorganic chemical vapor deposition (MOCVD). We have found that a 2 hour exposure to a 13.56 MHz hydrogen plasma at 275 C reduces the deep level concentration in the base regions of both n(+)-p and <span class="hlt">p(+)-n</span> heteroepitaxial InP cell structures from as-grown values of 5-7 x 10(exp 14) cm(exp -3), down to 3-5 x 10(exp 12) cm(exp -3). All dopants were successfully reactivated by a 400 C, 5 minute anneal with no detectable activation of deep levels. One to five analysis indicated a subsequent approximately 100 fold decrease in reverse leakage current at -1 volt reverse bias, and an improved built in voltage for the <span class="hlt">p(+)-n</span> structures. In addition to being passivated, dislocations are also shown to participate in secondary interactions during hydrogenation. We find that the presence of dislocations enhances hydrogen diffusion into the cell structure, and lowers the apparent dissociation energy of Zn-H complexes from 1.19 eV for homoepitaxial Zn-doped InP to 1.12 eV for heteroepitaxial Zn-doped InP. This is explained by additional hydrogen trapping at dislocations subsequent to the reactivation of Zn dopants after hydrogenation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JSemi..35h4002R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JSemi..35h4002R"><span id="translatedtitle">Simulating and modeling the breakdown voltage in a semi-insulating GaAs <span class="hlt">P+N</span> junction diode</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Resfa, A.; Menezla, Brahimi. R.; Benchhima, M.</p> <p>2014-08-01</p> <p>This work aims to determine the characteristic I (breakdown voltage) of the inverse current in a GaAs <span class="hlt">PN</span> junction diode, subject to a reverse polarization, while specifying the parameters that influence the breakdown voltage of the diode. In this work, we simulated the behavior of the ionization phenomenon by impact breakdown by avalanche of the <span class="hlt">PN</span> junctions, subject to an inverse polarization. We will take into account both the trapping model in a stationary regime in the <span class="hlt">P+N</span> structure using like material of basis the III-V compounds and mainly the GaAs semi-insulating in which the deep centers have in important densities. We are talking about the model of trapping in the space charge region (SCR) and that is the trap density donor and acceptor states. The carrier crossing the space charge region (SCR) of W thickness creates N electron—hole pairs: for every created pair, the electron and the hole are swept quickly by the electric field, each in an opposite direction, which comes back, according to an already accepted reasoning, to the crossing of the space charge region (SCR) by an electron or a hole. So the even N pair created by the initial particle provoke N2 ionizations and so forth. The study of the physical and electrical behaviour of semiconductors is based on the influence of the presence of deep centers on the characteristic I(V) current-tension, which requires the calculation of the electrostatic potential, the electric field, the integral of ionization, the density of the states traps, the diffusion current of minority in the regions (1) and (3), the current thermal generation in the region (2), the leakage current in the surface, and the breakdown voltage.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014ERL.....9k4011B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014ERL.....9k4011B"><span id="translatedtitle">Decomposing global crop <span class="hlt">yield</span> variability</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ben-Ari, Tamara; Makowski, David</p> <p>2014-11-01</p> <p>Recent food crises have highlighted the need to better understand the between-year variability of agricultural production. Although increasing future production seems necessary, the globalization of commodity markets suggests that the food system would also benefit from enhanced supplies stability through a reduction in the year-to-year variability. Here, we develop an analytical expression decomposing global crop <span class="hlt">yield</span> interannual variability into three informative components that quantify how evenly are croplands distributed in the world, the proportion of cultivated areas allocated to regions of above or below average variability and the covariation between <span class="hlt">yields</span> in distinct world regions. This decomposition is used to identify drivers of interannual <span class="hlt">yield</span> variations for four major crops (i.e., maize, rice, soybean and wheat) over the period 1961-2012. We show that maize production is fairly spread but marked by one prominent region with high levels of crop <span class="hlt">yield</span> interannual variability (which encompasses the North American corn belt in the USA, and Canada). In contrast, global rice <span class="hlt">yields</span> have a small variability because, although spatially concentrated, much of the production is located in regions of below-average variability (i.e., South, Eastern and South Eastern Asia). Because of these contrasted land use allocations, an even cultivated land distribution across regions would reduce global maize <span class="hlt">yield</span> variance, but increase the variance of global <span class="hlt">yield</span> rice. Intermediate results are obtained for soybean and wheat for which croplands are mainly located in regions with close-to-average variability. At the scale of large world regions, we find that covariances of regional <span class="hlt">yields</span> have a negligible contribution to global <span class="hlt">yield</span> variance. The proposed decomposition could be applied at any spatial and time scales, including the yearly time step. By addressing global crop production stability (or lack thereof) our results contribute to the understanding of a key</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/2516221','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/2516221"><span id="translatedtitle">The micronucleus test and erythropoiesis. Effects of erythropoietin and a mutagen on the ratio of polychromatic to normochromatic erythrocytes (<span class="hlt">P/N</span> ratio).</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Suzuki, Y; Nagae, Y; Li, J; Sakaba, H; Mozawa, K; Takahashi, A; Shimizu, H</p> <p>1989-11-01</p> <p>It is considered that a decrease of the ratio of polychromatic erythrocytes (PCE) to normochromatic erythrocytes (NCE) (<span class="hlt">P/N</span>) in the micronucleus test is an indicator of bone marrow toxicity induced by mutagens. However, the exact meaning of fluctuation in the <span class="hlt">P/N</span> ratio is not yet known. We have studied this point by counting the total number of erythrocytes and nucleated cells in the bone marrow following various treatments. The <span class="hlt">P/N</span> ratio decreased gradually with time after administration of mitomycin C. Our data suggest that the decrease of <span class="hlt">P/N</span> ratio was attributable to an increase in the numbers of the denominator, i.e. NCE, caused by rapid differentiation and multiplication or denucleation of erythroblasts which remained in the bone marrow instead of entering the peripheral blood stream. A decrease of <span class="hlt">P/N</span> ratio was also observed in the early phase after administration of erythropoietin, an agent which induces differentiation and multiplication of erythroblasts. This phenomenon might result from an increase of PCE delivery into the blood circulation. However, following the initial decrease, the <span class="hlt">P/N</span> ratio increased gradually 48 h after administration of erythropoietin. It is supposed that this increase probably resulted from an increase in PCE in the bone marrow due to the direct effects of erythropoietin on erythropoiesis. The drastic change in erythropoiesis in the bone marrow induced by either mutagen or erythropoietin treatment will affect the fluctuations of the <span class="hlt">P/N</span> ratio or the number of micronucleated erythrocytes per non-micronucleated erythocytes in the micronucleus test. This contrasts with the original explanation for such fluctuations which attributed them to replenishment of the marrow by peripheral blood. PMID:2516221</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19840030316&hterms=Herbicides&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DHerbicides','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19840030316&hterms=Herbicides&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DHerbicides"><span id="translatedtitle">Grapevine canopy reflectance and <span class="hlt">yield</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Minden, K. A.; Philipson, W. R.</p> <p>1982-01-01</p> <p>Field spectroradiometric and airborne multispectral scanner data were applied in a study of Concord grapevines. Spectroradiometric measurements of 18 experimental vines were collected on three dates during one growing season. Spectral reflectance, determined at 30 intervals from 0.4 to 1.1 microns, was correlated with vine <span class="hlt">yield</span>, pruning weight, clusters/vine, and nitrogen input. One date of airborne multispectral scanner data (11 channels) was collected over commercial vineyards, and the average radiance values for eight vineyard sections were correlated with the corresponding average <span class="hlt">yields</span>. Although some correlations were significant, they were inadequate for developing a reliable <span class="hlt">yield</span> prediction model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5031','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5031"><span id="translatedtitle">Novel InGaAsN <span class="hlt">pn</span> Junction for High-Efficiency Multiple-Junction Solar Cells</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Allerman, A.A.; Chang, P.C.; Gee, J.M.; Hammons, B.E.; Hou, H.Q.; Jones, E.D.; Kurtz, S.R.; Reinhardt, K.C.</p> <p>1999-03-26</p> <p>We report the application of a novel material, InGaAsN, with bandgap energy of 1.05 eV as a junction in an InGaP/GaAs/InGaAsN/Ge 4-junction design. Results of the growth and structural, optical, and electrical properties were demonstrated, showing the promising perspective of this material for ultra high efficiency solar cells. Photovoltaic properties of an as-grown <span class="hlt">pn</span> diode structure and improvement through post growth annealing were also discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730001990','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730001990"><span id="translatedtitle">A study of the electrical properties of <span class="hlt">p-n</span> junctions formed by ion-implantation into gallium arsenide</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lin, A. H.</p> <p>1972-01-01</p> <p>In the process of ion implantation, ion beams bombard the surface and create undesirable surface effects. The surface effects were investigated, and surface leakage currents were shown to be reduced by surface treatment. I-V characteristics and C-V measurements were obtained for the Zn-GaAs and Zn-(In,Ga)As junction is considered as a p-i-n heterojunction, without generation-recombination current. The Zn-GaAs junction is considered as a <span class="hlt">p-n</span> homojunction with appreciable generation-recombination currents.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19870033963&hterms=chemical+etching&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dchemical%2Betching','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19870033963&hterms=chemical+etching&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dchemical%2Betching"><span id="translatedtitle">Formation of a <span class="hlt">pn</span> junction on an anisotropically etched GaAs surface using metalorganic chemical vapor deposition</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Leon, R. P.; Bailey, S. G.; Mazaris, G. A.; Williams, W. D.</p> <p>1986-01-01</p> <p>A continuous p-type GaAs epilayer has been deposited on an n-type sawtooth GaAs surface using MOCVD. A wet chemical etching process was used to expose the intersecting (111)Ga and (-1 -1 1)Ga planes with 6-micron periodicity. Charge-collection microscopy was used to verify the presence of the <span class="hlt">pn</span> junction thus formed and to measure its depth. The ultimate goal of this work is to fabricate a V-groove GaAs cell with improved absorptivity, high short-circuit current, and tolerance to particle radiation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22066614','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22066614"><span id="translatedtitle">N.G. Basov and early works on semiconductor lasers at <span class="hlt">P.N</span>. Lebedev Physics Institute</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Eliseev, P G</p> <p>2012-12-31</p> <p>A survey is presented of works on creation and investigation of semiconductor lasers during 1957 - 1977 at the <span class="hlt">P.N</span>. Lebedev Physics Institute. Many of these works were initiated by N.G. Basov, starting from pre-laser time, when N.G. Basov and his coworkers formulated principal conditions of creation of lasers on interband transitions in semiconductors. Main directions of further works were diode lasers based on various materials and structures, their characteristics of output power, high-speed operation and reliability. (special issue devoted to the 90th anniversary of n.g. basov)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21370739','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21370739"><span id="translatedtitle">Investigation of the Exclusive {sup 3}He(e,e{sup '}<span class="hlt">pn</span>){sup 1}H Reaction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Middleton, D. G.; Grabmayr, P.; Hehl, T.; Heim, J.; Martin, I.; Moschini, F.; Annand, J. R. M.; Glazier, D. I.; MacGregor, I. J. D.; McGeorge, J. C.; Monstad, K.; Rosner, G.; Watts, D. P.; Antelo, M. Ases; Ayerbe, C.; Baumann, D.; Bermuth, J.; Bernauer, J.; Boehm, R.; Ding, M.</p> <p>2009-10-09</p> <p>Cross sections for the {sup 3}He(e,e{sup '}<span class="hlt">pn</span>){sup 1}H reaction were measured for the first time at energy transfers of 220 and 270 MeV for several momentum transfers ranging from 300 to 450 MeV/c. Cross sections are presented as a function of the momentum of the recoil proton and the momentum transfer. Continuum Faddeev calculations using the Argonne V18 and Bonn-B nucleon-nucleon potentials overestimate the measured cross sections by a factor 5 at low recoil proton momentum with the discrepancy becoming smaller at higher recoil proton momentum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22261773','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22261773"><span id="translatedtitle">Multi-terminal magnetotransport measurements over a tunable graphene <span class="hlt">p-n</span> junction created by AFM-nanomachining</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Schmidt, H.; Smirnov, D.; Rode, J.; Haug, R. J.</p> <p>2013-12-04</p> <p>An Atomic Force Microscope is used to alter one part of a single layer graphene sample locally. Transport experiments at low temperatures are then used to characterize the different parts independently with field effect and Hall measurements. It is shown, that the nanomachining leads to an effective doping in the altered area and therefore to a difference in the charge carrier density of Δn = 3.5 ⋅ 10{sup 15}m{sup −2} between the unchanged and changed part. These two parts can be tuned with a global backgate to form a junction of different polarity, i.e. a <span class="hlt">p-n</span> junction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5237312','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5237312"><span id="translatedtitle">Formation of a <span class="hlt">pn</span> junction on an anisotropically etched GaAs surface using metalorganic chemical vapor deposition</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Leon, R.P.; Bailey, S.G.; Mazaris, G.A.; Williams, W.D.</p> <p>1986-10-13</p> <p>A continuous p-type GaAs epilayer has been deposited on an n-type sawtooth GaAs surface using metalorganic chemical vapor deposition. A wet chemical etching process was used to expose the intersecting (111)Ga and (1-bar1-bar1)Ga planes with 6 ..mu..m periodicity. Charge collection microscopy was used to verify the presence of the <span class="hlt">pn</span> junction thus formed and to measure its depth. The ultimate goal of this work is to fabricate a V-groove GaAs cell with improved absorptivity, high short-circuit current, and tolerance to particle radiation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1714755D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1714755D"><span id="translatedtitle">Comparison of CDOM EEMs Characteristics along F and <span class="hlt">PN</span> section in Eastern China Sea: significance for sources tracing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Du, Yong; Zhang, Xiaoyu; Jiang, Binbin; Huang, Dasong; Yao, Lingling</p> <p>2015-04-01</p> <p>In this paper, a total of 28 water samples were collected mainly from three sections(C section in the Yangtze river inner estuary, <span class="hlt">PN</span> section and F section on the spindle of Changjiang diluted water influenced by different hydrodynamic processes),which taken on two cruises in spring and summer of 2011. Absorption and fluorescence spectroscopy were measured along with dissolved organic carbon(DOC) concentrations and temperature, salinity and another environmental parameters to characterize the material sources and environmental implications of dissolved organic matter(DOM). Two protein-like components(tyrosine-like peak B and tryptophan-like peak T1), and two humic-like components(marine humic-like peak M and ultraviolet region humic-like peak A ) were identified by PARAFAC. We discussed CDOM distribution characteristic, material composition, and influence factors during the slowly dilution process of Changjiang diluted water into the east China sea by comparing the correlation of the CDOM absorption, fluorescence intensity, and fluorescence peak with DOC, in order to provide the based biogeochemistry theory basis for building DOC implications using CDOM fluorescence properties. The results revealed that:1) the Yangtze river and its inner estuary (upstream of the river mouth) were detected a higher amount of humic-like components. With the rapid dilution (or settlement) at the inner estuary, the humic-like components would further spread and dilute slowly on <span class="hlt">PN</span> section and F section. On <span class="hlt">PN</span> section, the terrigenous material is the main source material, and the main mechanism of CDOM distribution characteristics is controlled by dilution diffusion. Affected by the water mass convergence, marine dissolved organic matter in local waters had obvious input. However, due to the complexed hydrodynamic environment on F section, the input of terrigenous material has many ways. The influence of marine dissolved organic matter increased with the offshore distance increases.2</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3439349','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3439349"><span id="translatedtitle">MYLIP <span class="hlt">p.N</span>342S polymorphism is not associated with lipid profile in the Brazilian population</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2012-01-01</p> <p>Background A recent study investigated the MYLIP region in the Mexican population in order to fine-map the actual susceptibility variants of this locus. The <span class="hlt">p.N</span>342S polymorphism was identified as the underlying functional variant accounting for one of the previous signals of genome-wide association studies and the N342 allele was associated with higher cholesterol concentrations in Mexican dyslipidemic individuals. To date, there is no further evaluation on this genotype-phenotype association in the literature. In this scenario, and because of a possible pharmacotherapeutic target of dyslipidemia, the main aim of this study was to assess the influence of the MYLIP <span class="hlt">p.N</span>342S polymorphism on lipid profile in Brazilian individuals. Methods 1295 subjects of the general population and 1425 consecutive patients submitted to coronary angiography were selected. General characteristics, biochemical tests, blood pressures, pulse wave velocity, and coronary artery disease scores were analyzed. Genotypes for the MYLIP rs9370867 (<span class="hlt">p.N</span>342S, c.G1025A) polymorphism were detected by high resolution melting analysis. Results No association of the MYLIP rs9370867 genotypes with lipid profile, hemodynamic data, and coronary angiographic data was found. Analysis stratified by hyperlipidemia, gender, and ethnicity was also performed and the sub-groups presented similar results. In both general population and patient samples, the MYLIP rs9370867 polymorphism was differently distributed according to ethnicity. In the general population, subjects carrying GG genotypes had higher systolic blood pressure (BP), diastolic BP, and mean BP values (129.0 ± 23.3; 84.9 ± 14.6; 99.5 ± 16.8 mmHg) compared with subjects carrying AA genotypes (123.7 ± 19.5; 81.6 ± 11.8; 95.6 ± 13.6 mmHg) (p = 0.01; p = 0.02; p = 0.01, respectively), even after adjustment for covariates. However, in analysis stratified by ethnicity, this finding was not found and there is no</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21596540','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21596540"><span id="translatedtitle">Synthesis of N=127 isotones through (<span class="hlt">p,n</span>) charge-exchange reactions induced by relativistic {sup 208}Pb projectiles</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Morales, A. I.; Benlliure, J.; Alvarez-Pol, H.; Casarejos, E.; Dragosavac, D.; Perez-Loureiro, D.; Verma, S.; Agramunt, J.; Molina, F.; Rubio, B.; Algora, A.; Alkhomashi, N.; Farrelly, G.; Gelletly, W.; Pietri, S.; Podolyak, Z.; Regan, P. H.; Steer, S. J.; Boutachkov, P.; Caceres, L. S.</p> <p>2011-07-15</p> <p>The production cross sections of four N=127 isotones ({sup 207}Hg, {sup 206}Au, {sup 205}Pt, and {sup 204}Ir) have been measured using (<span class="hlt">p,n</span>) charge-exchange reactions, induced in collisions of a {sup 208}Pb primary beam at 1 A GeV with a Be target. These data allow one to investigate the use of a reaction mechanism to extend the limits of the chart of nuclides toward the important r-process nuclei in the region of the third peak of elemental abundance distribution.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1988IEDL....9..368D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1988IEDL....9..368D"><span id="translatedtitle">Influence of perimeter recombination on high-efficiency GaAs <span class="hlt">p/n</span> heteroface solar cells</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Demoulin, Paul D.; Melloch, Michael R.; Lundstrom, Mark S.; Carpenter, M. S.; Tobin, Stephen P.</p> <p>1988-08-01</p> <p>Perimeter recombination currents have been characterized for 0.5-cm-square and 2-cm-square <span class="hlt">p/n</span> GaAs solar cells. Measurements show that perimeter recombination dominates the n = 2 dark current component of these high-efficiency solar cells. The results also suggest that perimeter recombination will be substantial even in much-larger-area solar cells. Although little influence on open-circuit voltage is expected, perimeter recombination may adversely affect the cell's one-sun fill factor. Because of its importance to one-sun applications, recombination at the junction perimeter must be suppressed before GaAs solar cells approach their limiting conversion efficiencies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/983653','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/983653"><span id="translatedtitle">Ejectile Polarization for $^2 H(e,e'\\vec <span class="hlt">p)n</span>$ at GeV energies</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Jeschonnek, Sabine; van Orden, Jay Wallace</p> <p>2010-01-01</p> <p>We perform a fully relativistic calculation of the $^2 H(e,e'\\vec <span class="hlt">p)n</span>$ reaction in the impulse approximation employing the Gross equation to describe the deuteron ground state, and we use the SAID parametrization of the full NN scattering amplitude to describe the final state interactions (FSIs). The formalism for treating the ejectile polarization with a spin projection on an arbitrary axes is discussed. We show results for the six relevant asymmetries and discuss the role of spin-dependent FSI contributions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4584985','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4584985"><span id="translatedtitle">Photosynthetic characteristics of the subtending leaf of cotton boll at different fruiting branch nodes and their relationships with lint <span class="hlt">yield</span> and fiber quality</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Liu, Jingran; Meng, Yali; Lv, Fengjuan; Chen, Ji; Ma, Yina; Wang, Youhua; Chen, Binglin; Zhang, Lei; Zhou, Zhiguo</p> <p>2015-01-01</p> <p>To investigate photosynthetic characteristics of the subtending leaf at the 2–3rd and 10–11th fruiting branch (FBN, FB2–3, and FB10–11), and their relationship with cotton <span class="hlt">yield</span> and quality, field experiments were conducted using two cotton cultivars, Kemian 1 and Sumian 15. The results showed that with FBN increasing, chlorophyll (Chl) components, <span class="hlt">Pn</span> and non-photochemical quenching (NPQ) in the subtending leaf significantly declined, while soluble sugar, amino acid and their ratio (CSS/CAA) as well as Fv/Fm increased. These results indicated that (1) non-radiative dissipation of excess light energy at FB2–3 was reduced to improve solar energy utilization efficiency to compensate for lower <span class="hlt">Pn</span>, (2) higher NPQ at FB10−11 played a role in leaf photo-damage avoidance, (3) boll weight was related to the CSS/CAA ratio rather than carbohydrates content alone, (4) with FBN increasing, lint biomass and lint/seed ratio increased significantly, but lint <span class="hlt">yield</span> decreased due to lower relative amount of bolls, and (5) the decreases in <span class="hlt">Pn</span>, sucrose content and CSS/CAA in the subtending leaf at FB2–3 resulted in lower boll weight and fiber strength. PMID:26442060</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840013853','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840013853"><span id="translatedtitle">Brazil wheat <span class="hlt">yield</span> covariance model</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Callis, S. L.; Sakamoto, C.</p> <p>1984-01-01</p> <p>A model based on multiple regression was developed to estimate wheat <span class="hlt">yields</span> for the wheat growing states of Rio Grande do Sul, Parana, and Santa Catarina in Brazil. The meteorological data of these three states were pooled and the years 1972 to 1979 were used to develop the model since there was no technological trend in the <span class="hlt">yields</span> during these years. Predictor variables were derived from monthly total precipitation, average monthly mean temperature, and average monthly maximum temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016EPJWC.12201008L&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016EPJWC.12201008L&link_type=ABSTRACT"><span id="translatedtitle">Fission <span class="hlt">yield</span> measurements at IGISOL</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lantz, M.; Al-Adili, A.; Gorelov, D.; Jokinen, A.; Kolhinen, V. S.; Mattera, A.; Moore, I.; Penttilä, H.; Pomp, S.; Prokofiev, A. V.; Rakopoulos, V.; Rinta-Antila, S.; Simutkin, V.; Solders, A.</p> <p>2016-06-01</p> <p>The fission product <span class="hlt">yields</span> are an important characteristic of the fission process. In fundamental physics, knowledge of the <span class="hlt">yield</span> distributions is needed to better understand the fission process. For nuclear energy applications good knowledge of neutroninduced fission-product <span class="hlt">yields</span> is important for the safe and efficient operation of nuclear power plants. With the Ion Guide Isotope Separator On-Line (IGISOL) technique, products of nuclear reactions are stopped in a buffer gas and then extracted and separated by mass. Thanks to the high resolving power of the JYFLTRAP Penning trap, at University of Jyväskylä, fission products can be isobarically separated, making it possible to measure relative independent fission <span class="hlt">yields</span>. In some cases it is even possible to resolve isomeric states from the ground state, permitting measurements of isomeric <span class="hlt">yield</span> ratios. So far the reactions U(p,f) and Th(p,f) have been studied using the IGISOL-JYFLTRAP facility. Recently, a neutron converter target has been developed utilizing the Be(p,xn) reaction. We here present the IGISOL-technique for fission <span class="hlt">yield</span> measurements and some of the results from the measurements on proton induced fission. We also present the development of the neutron converter target, the characterization of the neutron field and the first tests with neutron-induced fission.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27548477','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27548477"><span id="translatedtitle">The Expression of TaRca2-α Gene Associated with Net Photosynthesis Rate, Biomass and Grain <span class="hlt">Yield</span> in Bread Wheat (Triticum aestivum L.) under Field Conditions.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Saeed, Iqbal; Bachir, Daoura Goudia; Chen, Liang; Hu, Yin-Gang</p> <p>2016-01-01</p> <p>Improvement in activation of Rubisco by Rubisco activase can potentially enhance CO2 assimilation and photosynthetic efficiency in plants. The three homoeologous copies of TaRca2-α were identified on chromosomes 4AL, 4BS and 4DS (TaRca2-α-4AL, TaRca2-α-4BS, and TaRca2-α-4DS) in bread wheat. Expression patterns of the three copies at heading (Z55), anthesis (Z67) and grain-filling (Z73) stages were investigated through qRT-PCR analyses in a panel of 59 bread wheat genotypes and their effects on net photosynthesis rate (<span class="hlt">Pn</span>), biomass plant-1 (BMPP) and grain <span class="hlt">yield</span> plant-1 (GYPP) were further explored. Different but similar expression patterns were observed for the three copies of TaRca2-α at the three growth stages with highest expression at grain-filling stage. TaRca2-α-4BS expressed higher at the three stages than TaRca2-α-4AL and TaRca2-α-4DS. The 59 genotypes could be clustered into three groups as high (7 genotypes), intermediate (41 genotypes) and low (11 genotypes) expression based on the expression of the three copies of TaRca2-α at three growth stages. Significant variations (P<0.01) were observed among the three groups of bread wheat genotypes for <span class="hlt">Pn</span>, BMPP and GYPP. Generally, the genotypes with higher TaRca2-α expression also showed higher values for <span class="hlt">Pn</span>, BMPP and GYPP. The expressions of the three copies of TaRca2-α at heading, anthesis and grain-filling stages were positively correlated with <span class="hlt">Pn</span>, BMPP and GYPP (P<0.01) with stronger association for TaRca2-α-4BS at grain-filling stage. These results revealed that the expression of TaRca2-α contribute substantially to <span class="hlt">Pn</span>, BMPP and GYPP, and suggested that manipulating TaRca-α expression may efficiently improve <span class="hlt">Pn</span>, BMPP and GYPP in bread wheat and detecting TaRca-α expression levels with emphasis on TaRca2-α-4BS may be a positive strategy for selection in improving photosynthetic efficiency and grain <span class="hlt">yield</span> of bread wheat. PMID:27548477</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4993480','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4993480"><span id="translatedtitle">The Expression of TaRca2-α Gene Associated with Net Photosynthesis Rate, Biomass and Grain <span class="hlt">Yield</span> in Bread Wheat (Triticum aestivum L.) under Field Conditions</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Saeed, Iqbal; Bachir, Daoura Goudia; Chen, Liang; Hu, Yin-Gang</p> <p>2016-01-01</p> <p>Improvement in activation of Rubisco by Rubisco activase can potentially enhance CO2 assimilation and photosynthetic efficiency in plants. The three homoeologous copies of TaRca2-α were identified on chromosomes 4AL, 4BS and 4DS (TaRca2-α-4AL, TaRca2-α-4BS, and TaRca2-α-4DS) in bread wheat. Expression patterns of the three copies at heading (Z55), anthesis (Z67) and grain-filling (Z73) stages were investigated through qRT-PCR analyses in a panel of 59 bread wheat genotypes and their effects on net photosynthesis rate (<span class="hlt">Pn</span>), biomass plant-1 (BMPP) and grain <span class="hlt">yield</span> plant-1 (GYPP) were further explored. Different but similar expression patterns were observed for the three copies of TaRca2-α at the three growth stages with highest expression at grain-filling stage. TaRca2-α-4BS expressed higher at the three stages than TaRca2-α-4AL and TaRca2-α-4DS. The 59 genotypes could be clustered into three groups as high (7 genotypes), intermediate (41 genotypes) and low (11 genotypes) expression based on the expression of the three copies of TaRca2-α at three growth stages. Significant variations (P<0.01) were observed among the three groups of bread wheat genotypes for <span class="hlt">Pn</span>, BMPP and GYPP. Generally, the genotypes with higher TaRca2-α expression also showed higher values for <span class="hlt">Pn</span>, BMPP and GYPP. The expressions of the three copies of TaRca2-α at heading, anthesis and grain-filling stages were positively correlated with <span class="hlt">Pn</span>, BMPP and GYPP (P<0.01) with stronger association for TaRca2-α-4BS at grain-filling stage. These results revealed that the expression of TaRca2-α contribute substantially to <span class="hlt">Pn</span>, BMPP and GYPP, and suggested that manipulating TaRca-α expression may efficiently improve <span class="hlt">Pn</span>, BMPP and GYPP in bread wheat and detecting TaRca-α expression levels with emphasis on TaRca2-α-4BS may be a positive strategy for selection in improving photosynthetic efficiency and grain <span class="hlt">yield</span> of bread wheat. PMID:27548477</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27228602','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27228602"><span id="translatedtitle">[Flag leaf photosynthetic characteristics, change in chlorophyll fluorescence parameters, and their relationships with <span class="hlt">yield</span> of winter wheat sowed in spring].</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Xu, Lan; Gao, Zhi-qang; An, Wei; Li, Yan-liang; Jiao, Xiong-fei; Wang, Chuang-yun</p> <p>2016-01-01</p> <p>With five good winter wheat cultivars selected from the middle and lower reaches of Yangtze River and Southwest China as test materials, a field experiment in Xinding basin area of Shanxi Province was conducted to study the photosynthetic characteristics, chlorophyll content, and chlorophyll fluorescence parameters of flag leaf at different sowing dates, as well as the correlations between these indices and <span class="hlt">yield</span> for two years (2013-2014). The results showed that the difference in most fluorescence parameters except chlorophyll content among cultivars was significant. The correlations between these fluorescence parameters and <span class="hlt">yield</span> were significant. The variation coefficient of chlorophyll (Chl) content was low (0.12-0.17), and that of performance index based on absorption (PIabs) was high (0.32-0.39), with the partial correlation coefficients of them with grain <span class="hlt">yield</span> from 2013 to 2014 ranged in 0.70-0.81. Under the early sowing condition, the grain <span class="hlt">yield</span> positively correlated with PIabs at flowering and filling stages and chlorophyll content at grain filling stage, but negatively correlated with the relative variable fluorescence at I point (Vi) at grain filling stage. About 81.1%-82.8% of grain <span class="hlt">yield</span> were determined by the variations of PIabs, Chl, and Vi. Wheat cultivars had various performances in the treatments with different sowing dates and a consistent trend was observed in the two experimental years. Among these 5 cultivars, Yangmai 13 was suitable for early sowing, with the flag leaf photosynthetic rate (<span class="hlt">Pn</span>), Chl, most fluorescence parame-ters, and grain <span class="hlt">yield</span> showed obviously high levels. In conclusion, under early sowing condition chlorophyll content at grain filling stages, PIabs at flowering and filling stages, and <span class="hlt">Pn</span> were important indices for selecting wheat cultivars with high photosynthetic efficiency. PMID:27228602</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5681155','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5681155"><span id="translatedtitle">Acid soil infertility effects on peanut <span class="hlt">yields</span> and <span class="hlt">yield</span> components</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Blamey, F.P.C.</p> <p>1983-01-01</p> <p>The interpretation of soil amelioration experiments with peanuts is made difficult by the unpredictibility of the crop and by the many factors altered when ameliorating acid soils. The present study was conducted to investigate the effects of lime and gypsum applications on peanut kernel <span class="hlt">yield</span> via the three first order <span class="hlt">yield</span> components, pods per ha, kernels per pod, and kernel mass. On an acid medium sandy loam soil (typic Plinthustult), liming resulted in a highly significant kernel <span class="hlt">yield</span> increase of 117% whereas gypsum applications were of no significant benefit. As indicated by path coefficient analysis, an increase in the number of pods per ha was markedly more important in increasing <span class="hlt">yield</span> than an increase in either the number of kernels per pod or kernel mass. Furthermore, exch. Al was found to be particularly detrimental to pod number. It was postulated that poor peanut <span class="hlt">yields</span> resulting from acid soil infertility were mainly due to the depressive effect of exch. Al on pod number. Exch. Ca appeared to play a secondary role by ameliorating the adverse effects of exch. Al.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26123121','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26123121"><span id="translatedtitle">Fabrication of SnO2-SnO nanocomposites with <span class="hlt">p-n</span> heterojunctions for the low-temperature sensing of NO2 gas.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Li, Lei; Zhang, Chunmei; Chen, Wei</p> <p>2015-07-28</p> <p>In this report, the fabrication of a novel SnO2-SnO nanostructure with <span class="hlt">p-n</span> heterojunctions has been achieved through a facile one-pot and low-cost hydrothermal process. The structure and properties of the nanocomposite were analyzed with X-ray techniques and electron microscopy. HRTEM characterization showed that the <span class="hlt">p-n</span> heterojunctions were formed with small n-type SnO2 nanocrystals dispersed on the surface of large p-type SnO crystals. Compared to the single SnO2-based material, a gas sensor fabricated from the SnO2-SnO composite exhibited an enhanced sensing performance for NO2 gas detection, with a limit of detection and sensitivity of 0.1 ppm and 0.26 ppm(-1), respectively, at a relatively low operating temperature (50 °C). Moreover, the <span class="hlt">p-n</span> heterojunctions exhibited high sensing selectivity for NO2. Such a high sensing sensitivity and a low operating temperature make the SnO2-SnO <span class="hlt">p-n</span> nanomaterial a promising gas sensor for practical NO2 gas detection. The improved sensing response characteristics of the hybrid material could be attributed to the <span class="hlt">p-n</span> junctions formed through the in situ growth of SnO2 nanocrystals on SnO nanoplates. The present study is helpful for the design of novel gas sensing materials and the development of NO2 gas sensors. PMID:26123121</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20000032849&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DP-n%2Bjunction','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20000032849&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DP-n%2Bjunction"><span id="translatedtitle"><span class="hlt">P/N</span> In(Al) GaAs Multijunction Laser Power Converters</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wojtczuk, Steven; Parodos, Themis; Walker, Gilbert</p> <p>1994-01-01</p> <p>Eight In(Al)GaAs <span class="hlt">P/N</span> junctions grown epitaxially on a semi-insulating wafer were monolithically integrated in series to boost the approx. 0.4 V photovoltage per typical In(Al)GaAs junction to over 3 volts for the 1 sq cm laser power converter (LPC) chip. This is the first report of a multijunction LPC for the 1.3 to 1.5 microns wavelength range. This wavelength range is optimum for laser power transmission over low- loss single-mode silica optical fiber, and is also useful with high efficiency 1.315 microns iodine lasers in free-space power transmission. Advantages of multijunction LPC designs include the need for less circuitry for power reconditioning and the potential for lower I(exp 2)R power loss. As an example, these LPCs have a responsivity of approx.1 amp/watt. With a single junction LPC, 100 watts/sq cm incident power would lead to about 100 A/sq cM short-circuit current at approx. 0.4 V open-circuit voltage. One disadvantage is the large current would lead to a large 1(exp 2)R loss which would lower the fill factor so that 40 wattS/sq cm output would not be obtained. Another is that few circuits are designed to work at 0.4 volts, so DC-DC power conversion circuitry would be necessary to raise the voltage to a reasonable level. The multijunction LPC being developed in this program is a step toward solving these problems. In the above example, an eight-junction LPC would have eight times the voltage, approx. 3 V, so that DC-DC power conversion may not be needed in many instances. In addition, the multijunction LPC would have 1/8 the current of a single-junction LPC, for only 1/64 the 1(exp 2)R loss if the series resistance is the same. Working monolithic multijunction laser power converters (LPCs) were made in two different compositions of the ln(x)Al(y)Ga(l-x-y)As semiconductor alloy, In(0.53)Ga(0.47)As (0.74 eV) and In(0.5)Al(0.1)Ga(0.4)As (0.87 eV). The final 0.8 sq cm LPCs had output voltages of about 3 volts and output currents up to about one-half amp</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26771206','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26771206"><span id="translatedtitle">Black Phosphorus-Zinc Oxide Nanomaterial Heterojunction for <span class="hlt">p-n</span> Diode and Junction Field-Effect Transistor.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jeon, Pyo Jin; Lee, Young Tack; Lim, June Yeong; Kim, Jin Sung; Hwang, Do Kyung; Im, Seongil</p> <p>2016-02-10</p> <p>Black phosphorus (BP) nanosheet is two-dimensional (2D) semiconductor with distinct band gap and attracting recent attention from researches because it has some similarity to gapless 2D semiconductor graphene in the following two aspects: single element (P) for its composition and quite high mobilities depending on its fabrication conditions. Apart from several electronic applications reported with BP nanosheet, here we report for the first time BP nanosheet-ZnO nanowire 2D-1D heterojunction applications for <span class="hlt">p-n</span> diodes and BP-gated junction field effect transistors (JFETs) with n-ZnO channel on glass. For these nanodevices, we take advantages of the mechanical flexibility of p-type conducting of BP and van der Waals junction interface between BP and ZnO. As a result, our BP-ZnO nanodimension <span class="hlt">p-n</span> diode displays a high ON/OFF ratio of ∼10(4) in static rectification and shows kilohertz dynamic rectification as well while ZnO nanowire channel JFET operations are nicely demonstrated by BP gate switching in both electrostatics and kilohertz dynamics. PMID:26771206</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19790056877&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DP-n%2Bjunction','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19790056877&hterms=P-n+junction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DP-n%2Bjunction"><span id="translatedtitle">Forward-bias capacitance and current measurements for determining lifetimes and band narrowing in <span class="hlt">p-n</span> junction solar cells</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Neugroschel, A.; Chen, P. J.; Pao, S. C.; Lindholm, F. A.</p> <p>1978-01-01</p> <p>A new method is described and illustrated for determining the minority-carrier diffusion length and lifetime in the base region of <span class="hlt">p-n</span> junction solar cells. The method requires only capacitance measurements at the device terminals and its accuracy is estimated to be + or - 5%. It is applied to a set of silicon <span class="hlt">p-n</span> junction devices and the values of the diffusion lengths agree with those obtained using the current response to X-ray excitation but disagree with those obtained by the OCVD method. The reasons for the relative inaccuracy of OCVD applied to silicon devices are discussed. The capacitance method includes corrections for a two-dimensional fringing effects which occur in small area devices. For a device having highly-doped base region and surface (emitter) layer, the method can be extended to enable the determination of material properties of the degenerately doped surface layer. These material properties include the phenomenological emitter lifetime and a measure of the energy band-gap narrowing in the emitter. An alternate method for determining the energy band-gap narrowing from temperature dependence of emitter current is discussed and demonstrated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23389277','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23389277"><span id="translatedtitle">Direct electrical contact of slanted ITO film on axial <span class="hlt">p-n</span> junction silicon nanowire solar cells.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lee, Ya-Ju; Yao, Yung-Chi; Yang, Chia-Hao</p> <p>2013-01-14</p> <p>A novel scheme of direct electrical contact on vertically aligned silicon nanowire (SiNW) axial <span class="hlt">p-n</span> junction is demonstrated by means of oblique-angle deposition of slanted indium-tin-oxide (ITO) film for photovoltaic applications. The slanted ITO film exhibits an acceptable resistivity of 1.07 x 10⁻³Ω-cm underwent RTA treatment of T = 450°C, and the doping concentration and carrier mobility by Hall measurement amount to 3.7 x 10²⁰ cm⁻³ and 15.8 cm²/V-s, respectively, with an n-type doping polarity. Because of the shadowing effect provided by the SiNWs, the incident ITO vapor-flow is deposited preferentially on the top of SiNWs, which coalesces and eventually forms a nearly continuous film for the subsequent fabrication of grid electrode. Under AM 1.5 G normal illumination, our axial <span class="hlt">p-n</span> junction SiNW solar cell exhibits an open circuit voltage of VOC = 0.56 V, and a short circuit current of JSC = 1.54 mA/cm² with a fill factor of FF = 30%, resulting in a total power conversion efficiency of PEC = 0.26%. PMID:23389277</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016PhRvD..94b5032A&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016PhRvD..94b5032A&link_type=ABSTRACT"><span id="translatedtitle">Collective coordinate quantization and spin statistics of the solitons in the C <span class="hlt">PN</span> Skyrme-Faddeev model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Amari, Yuki; Klimas, Paweł; Sawado, Nobuyuki</p> <p>2016-07-01</p> <p>The C <span class="hlt">PN</span> extended Skyrme-Faddeev model possesses planar soliton solutions. We consider quantum aspects of the solutions applying collective coordinate quantization in regime of rigid body approximation. In order to discuss statistical properties of the solutions we include an Abelian Chern-Simons term (the Hopf term) in the Lagrangian. Since Π3(C P1)=Z then for N =1 the term becomes an integer. On the other hand for N >1 it became perturbative because Π3(C <span class="hlt">PN</span>) is trivial. The prefactor of the Hopf term (anyon angle) Θ is not quantized and its value depends on the physical system. The corresponding fermionic models can fix value of the angle Θ for all N in a way that the soliton with N =1 is not an anyon type whereas for N >1 it is always an anyon even for Θ =n π , n ∈Z . We quantize the solutions and calculate several mass spectra for N =2 . Finally we discuss generalization for N ≧3 .</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApSS..364..322S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApSS..364..322S"><span id="translatedtitle">NiO nanosheet/TiO2 nanorod-constructed <span class="hlt">p-n</span> heterostructures for improved photocatalytic activity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sun, Bin; Zhou, Guowei; Gao, Tingting; Zhang, Huaijin; Yu, Haohai</p> <p>2016-02-01</p> <p>NiO nanosheet/acid-corroded TiO2 nanorod (A-TiO2 nanorod) heterostructures with high photocatalytic activity were successfully fabricated via a facile and low-cost hydrothermal route. The as-prepared heterostructures featured NiO nanosheets with uniformly assembled A-TiO2 nanorods and a rough surface. The morphology, structure, and photoelectric properties of the pristine NiO nanosheets and TiO2-based nanomaterials were characterized in detail, and results revealed that secondary NiO nanosheets were successfully grown on TiO2 nanorod substrates to achieve a <span class="hlt">p-n</span> heterostructure between the cubic structure NiO and the TiO2 anatase phase. In comparison with P25, NiO nanosheets, TiO2 nanorods, and A-TiO2 nanorods, the proposed heterostructures exhibited markedly enhanced photocatalytic activity for the degradation of methyl orange under UV light irradiation. Specifically, the NiO nanosheet/A-TiO2 nanorod heterostructures exhibited the best photocatalytic activity, achieving 100% photocatalytic efficiency within 20 min. The observed enhancement in photocatalytic activity was attributed to the synergetic contributions of <span class="hlt">p-n</span> heterostructures and the large specific surface area of the catalyst, which may improve the separation of photogenerated electron-hole pairs and prolong the lifetime of charge carriers. The heterostructures could be easily recycled without observable decreases in photocatalytic activity because of their one-dimensional nanostructural property.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015OptEn..54e7104X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015OptEn..54e7104X"><span id="translatedtitle">Analysis of simulation of multiterminal electro-optic modulator based on <span class="hlt">p-n</span> junction in reverse bias</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xu, Kaikai; Liu, Siyang; Zhao, Jianming; Sun, Weifeng; Li, Guannpyng</p> <p>2015-05-01</p> <p>A study of a silicon metal oxide semiconductor (MOS)-type light-emitting device (LED) in which the <span class="hlt">p-n</span> junction works under a reverse bias and the gate voltage is applied to modulate the electric field distribution from the p+ region through the n region. The use of gate voltage could result in the generation of a field-induced junction which leads to a decrease of the operating voltage of the LED compared to the two terminal <span class="hlt">p-n</span> junction LED. The dynamics of the photonic emission in the structure and its related response time, and then a more detailed theoretical and simulation understanding of the photonic emission is achieved, which definitively demonstrates the capability of the device in which a reverse-bias region showing light modulation with multi-GHz bandwidth and gigabit-per-second data rate at near-infrared wavelength. Although the emitted optical power is weak, it is advantageous to utilize the device in all-silicon optoelectronic integrated circuits, especially for short-distance on-chip optical interconnects achieved by standard complementary MOS technology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AIPC.1733b0095S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AIPC.1733b0095S"><span id="translatedtitle">A simplified boron diffusion for preparing the silicon single crystal <span class="hlt">p-n</span> junction as an educational device</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shiota, Koki; Kai, Kazuho; Nagaoka, Shiro; Tsuji, Takuto; Wakahara, Akihiro; Rusop, Mohamad</p> <p>2016-07-01</p> <p>The educational method which is including designing, making, and evaluating actual semiconductor devices with learning the theory is one of the best way to obtain the fundamental understanding of the device physics and to cultivate the ability to make unique ideas using the knowledge in the semiconductor device. In this paper, the simplified Boron thermal diffusion process using Sol-Gel material under normal air environment was proposed based on simple hypothesis and the feasibility of the reproducibility and reliability were investigated to simplify the diffusion process for making the educational devices, such as <span class="hlt">p-n</span> junction, bipolar and pMOS devices. As the result, this method was successfully achieved making p+ region on the surface of the n-type silicon substrates with good reproducibility. And good rectification property of the <span class="hlt">p-n</span> junctions was obtained successfully. This result indicates that there is a possibility to apply on the process making pMOS or bipolar transistors. It suggests that there is a variety of the possibility of the applications in the educational field to foster an imagination of new devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012NatCo...3E1280Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012NatCo...3E1280Y"><span id="translatedtitle">Modulation-doped growth of mosaic graphene with single-crystalline <span class="hlt">p-n</span> junctions for efficient photocurrent generation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yan, Kai; Wu, Di; Peng, Hailin; Jin, Li; Fu, Qiang; Bao, Xinhe; Liu, Zhongfan</p> <p>2012-12-01</p> <p>Device applications of graphene such as ultrafast transistors and photodetectors benefit from the combination of both high-quality p- and n-doped components prepared in a large-scale manner with spatial control and seamless connection. Here we develop a well-controlled chemical vapour deposition process for direct growth of mosaic graphene. Mosaic graphene is produced in large-area monolayers with spatially modulated, stable and uniform doping, and shows considerably high room temperature carrier mobility of ~5,000 cm2 V-1 s-1 in intrinsic portion and ~2,500 cm2 V-1 s-1 in nitrogen-doped portion. The unchanged crystalline registry during modulation doping indicates the single-crystalline nature of <span class="hlt">p-n</span> junctions. Efficient hot carrier-assisted photocurrent was generated by laser excitation at the junction under ambient conditions. This study provides a facile avenue for large-scale synthesis of single-crystalline graphene <span class="hlt">p-n</span> junctions, allowing for batch fabrication and integration of high-efficiency optoelectronic and electronic devices within the atomically thin film.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23232410','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23232410"><span id="translatedtitle">Modulation-doped growth of mosaic graphene with single-crystalline <span class="hlt">p-n</span> junctions for efficient photocurrent generation.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yan, Kai; Wu, Di; Peng, Hailin; Jin, Li; Fu, Qiang; Bao, Xinhe; Liu, Zhongfan</p> <p>2012-01-01</p> <p>Device applications of graphene such as ultrafast transistors and photodetectors benefit from the combination of both high-quality p- and n-doped components prepared in a large-scale manner with spatial control and seamless connection. Here we develop a well-controlled chemical vapour deposition process for direct growth of mosaic graphene. Mosaic graphene is produced in large-area monolayers with spatially modulated, stable and uniform doping, and shows considerably high room temperature carrier mobility of ~5,000 cm(2) V(-1) s(-1) in intrinsic portion and ~2,500 cm(2) V(-1) s(-1) in nitrogen-doped portion. The unchanged crystalline registry during modulation doping indicates the single-crystalline nature of <span class="hlt">p-n</span> junctions. Efficient hot carrier-assisted photocurrent was generated by laser excitation at the junction under ambient conditions. This study provides a facile avenue for large-scale synthesis of single-crystalline graphene <span class="hlt">p-n</span> junctions, allowing for batch fabrication and integration of high-efficiency optoelectronic and electronic devices within the atomically thin film. PMID:23232410</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013APS..MAR.M7001S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013APS..MAR.M7001S"><span id="translatedtitle">Negative refractive index electron `optics', pseudospintronics and chiral tunneling in graphene <span class="hlt">pn</span> junction -- beating the Landauer switching limit?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sajjad, Redwan; Pan, Chenyun; Naeemi, Azad; Ghosh, Avik</p> <p>2013-03-01</p> <p>We use atomistic quantum kinetic calculations to demonstrate how graphene <span class="hlt">PN</span> junctions can switch with high ON currents, low OFF currents, steep gate transfer characteristics and unipolar rectification. The physics of such unconventional switching relies on (a) field-engineering with patterned gates to create a transmission gap, by sequential filtering of all propagating modes, and (b) using tilted junctions to suppress Klein tunneling under appropriate gate biasing, making that transmission gap gate tunable. The doping ratio of the junction dictates the energy range over which the tilt angle exceeds the critical angle for transmission, generating thereby a gate tunable transmission gap that enables switching at voltages less than the Landauer-Shannon thermal limit. The underlying physics involves a combination of `electron optics' driven by Snell's law, negative index metamaterial with a <span class="hlt">PN</span> junction, and pseudospin driven chiral tunneling, for which we also present experimental verification. [Sajjad et al, APL 99, 123101 (2011); Sajjad et al, PRB 86, 155412 (2012)]. Authors acknowledge financial grant from NRI-INDEX</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatSR...514795S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatSR...514795S"><span id="translatedtitle">Enhancement of the Si <span class="hlt">p-n</span> diode NIR photoresponse by embedding β-FeSi2 nanocrystallites</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shevlyagin, A. V.; Goroshko, D. L.; Chusovitin, E. A.; Galkin, K. N.; Galkin, N. G.; Gutakovskii, A. K.</p> <p>2015-10-01</p> <p>By using solid phase epitaxy of thin Fe films and molecular beam epitaxy of Si, a p+-Si/p-Si/β-FeSi2 nanocrystallites/n-Si(111) diode structure was fabricated. Transmission electron microscopy data confirmed a well-defined multilayered structure with embedded nanocrystallites of two typical sizes: 3-4 and 15-20 nm, and almost coherent epitaxy of the nanocrystallites with the Si matrix. The diode at zero bias conditions exhibited a current responsivity of 1.7 mA/W, an external quantum efficiency of about 0.2%, and a specific detectivity of 1.2 × 109 cm × Hz1/2/W at a wavelength of 1300 nm at room temperature. In the avalanche mode, the responsivity reached up to 20 mA/W (2% in terms of efficiency) with a value of avalanche gain equal to 5. The data obtained indicate that embedding of β-FeSi2 nanocrystallites into the depletion region of the Si <span class="hlt">p-n</span> junction results in expansion of the spectral sensitivity up to 1600 nm and an increase of the photoresponse by more than two orders of magnitude in comparison with a conventional Si <span class="hlt">p-n</span> junction. Thereby, fabricated structure combines advantage of the silicon photodiode functionality and simplicity with near infrared light detection capability of β-FeSi2.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25898025','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25898025"><span id="translatedtitle">Tunable Ultraviolet Photoresponse in Solution-Processed <span class="hlt">p-n</span> Junction Photodiodes Based on Transition-Metal Oxides.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Xie, Ting; Liu, Guannan; Wen, Baomei; Ha, Jong Y; Nguyen, Nhan V; Motayed, Abhishek; Debnath, Ratan</p> <p>2015-05-13</p> <p>Solution-processed <span class="hlt">p-n</span> heterojunction photodiodes have been fabricated based on transition-metal oxides in which NiO and ternary Zn(1-x)Mg(x)O (x = 0-0.1) have been employed as p-type and n-type semiconductors, respectively. Composition-related structural, electrical, and optical properties are also investigated for all the films. It has been observed that the bandgap of Zn(1-x)Mg(x)O films can be tuned between 3.24 and 3.49 eV by increasing Mg content. The fabricated highly visible-blind <span class="hlt">p-n</span> junction photodiodes show an excellent rectification ratio along with good photoresponse and quantum efficiency under ultraviolet (UV) illumination. With an applied reverse bias of 1 V and depending on the value of x, the maximum responsivity of the devices varies between 0.22 and 0.4 A/W and the detectivity varies between 0.17 × 10(12) and 2.2 × 10(12) cm (Hz)(1/2)/W. The photodetectors show an excellent UV-to-visible rejection ratio. Compositional nonuniformity has been observed locally in the alloyed films with x = 0.1, which is manifested in photoresponse and X-ray analysis data. This paper demonstrates simple solution-processed, low cost, band tunable photodiodes with excellent figures of merit operated under low bias. PMID:25898025</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26469092','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26469092"><span id="translatedtitle">Tunable GaTe-MoS2 van der Waals <span class="hlt">p-n</span> Junctions with Novel Optoelectronic Performance.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Feng; Wang, Zhenxing; Xu, Kai; Wang, Fengmei; Wang, Qisheng; Huang, Yun; Yin, Lei; He, Jun</p> <p>2015-11-11</p> <p><span class="hlt">P-n</span> junctions based on vertically stacked van der Waals (vdW) materials have attracted a great deal of attention and may open up unforeseen opportunities in electronics and optoelectronics. However, due to the lack of intrinsic p-type vdW materials, most previous studies generally adopted electrical gating, special electrode contacts, or chemical doping methods to realize <span class="hlt">p-n</span> vdW junctions. GaTe is an intrinsic p-type vdW material with a relatively high charge density, and it has a direct band gap that is independent of thickness. Here, we report the construction of ultrathin and tunable p-GaTe/n-MoS2 vdW heterostructure with high photovoltaic and photodetecting performance. The rectification ratio, external quantum efficiency, and photoresponsivity are as high as 4 × 10(5), 61.68%, and 21.83 AW(-1), respectively. In particular, the detectivity is up to 8.4 × 10(13) Jones, which is even higher than commercial Si, InGaAs photodetectors. This study demonstrates the promising potential of p-GaTe/n-MoS2 heterostructures for next-generation electronic and optoelectronic devices. PMID:26469092</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhCS.728e2006O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhCS.728e2006O"><span id="translatedtitle">Properties of the fullerene C60-containing <span class="hlt">PN</span> Lin49 in the SMC; Explanations of strong near-IR excess</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Otsuka, Masaaki; Kemper, Francisca; Leal-Ferreira, Marcelo L.; Aleman, Isabel; Bernard-Salas, Jeronimo; Cami, Jan; Ochsendorf, Bram; Peeters, Els</p> <p>2016-07-01</p> <p>We performed a detailed spectroscopic analysis of the fullerene C6o-containing planetary nebula (<span class="hlt">PN</span>) Lin49 in the Small Magellanic Cloud (SMC). Lin49 is a C-rich and metal- deficient <span class="hlt">PN</span> (Z∼⃒0.0006) and its nebular abundances are in agreement with the AGB model for the initially 1.25Mʘ stars with the metallicity Z = 0.001 of Fishlock et al. (2014, [1]). By stellar absorption fitting with TLUSTY, we derived stellar abundances, effective temperature, and surface gravity. We constructed the photo-ionization model with CLOUDY in order to investigate physical conditions of Lin49. The model with the 0.005-0.1 μm radius graphite and a constant hydrogen density shell could not fit the ∼⃒1-5 μm SED owing to the strong near-IR excess. We propose that the near-IR excess indicates (1) the presence of extremely small carbon molecules or (2) the presence of high-density structure surrounding the central star.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/880619','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/880619"><span id="translatedtitle">Process For Direct Integration Of A Thin-Film Silicon <span class="hlt">P-N</span> Junction Diode With A Magnetic Tunnel Junction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Toet, Daniel; Sigmon, Thomas W.</p> <p>2005-08-23</p> <p>A process for direct integration of a thin-film silicon <span class="hlt">p-n</span> junction diode with a magnetic tunnel junction for use in advanced magnetic random access memory (MRAM) cells for high performance, non-volatile memory arrays. The process is based on pulsed laser processing for the fabrication of vertical polycrystalline silicon electronic device structures, in particular <span class="hlt">p-n</span> junction diodes, on films of metals deposited onto low temperature-substrates such as ceramics, dielectrics, glass, or polymers. The process preserves underlayers and structures onto which the devices are typically deposited, such as silicon integrated circuits. The process involves the low temperature deposition of at least one layer of silicon, either in an amorphous or a polycrystalline phase on a metal layer. Dopants may be introduced in the silicon film during or after deposition. The film is then irradiated with short pulse laser energy that is efficiently absorbed in the silicon, which results in the crystallization of the film and simultaneously in the activation of the dopants via ultrafast melting and solidification. The silicon film can be patterned either before or after crystallization.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1175165','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1175165"><span id="translatedtitle">Process for direct integration of a thin-film silicon <span class="hlt">p-n</span> junction diode with a magnetic tunnel junction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Toet, Daniel; Sigmon, Thomas W.</p> <p>2004-12-07</p> <p>A process for direct integration of a thin-film silicon <span class="hlt">p-n</span> junction diode with a magnetic tunnel junction for use in advanced magnetic random access memory (MRAM) cells for high performance, non-volatile memory arrays. The process is based on pulsed laser processing for the fabrication of vertical polycrystalline silicon electronic device structures, in particular <span class="hlt">p-n</span> junction diodes, on films of metals deposited onto low temperature-substrates such as ceramics, dielectrics, glass, or polymers. The process preserves underlayers and structures onto which the devices are typically deposited, such as silicon integrated circuits. The process involves the low temperature deposition of at least one layer of silicon, either in an amorphous or a polycrystalline phase on a metal layer. Dopants may be introduced in the silicon film during or after deposition. The film is then irradiated with short pulse laser energy that is efficiently absorbed in the silicon, which results in the crystallization of the film and simultaneously in the activation of the dopants via ultrafast melting and solidification. The silicon film can be patterned either before or after crystallization.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/875136','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/875136"><span id="translatedtitle">Process for direct integration of a thin-film silicon <span class="hlt">p-n</span> junction diode with a magnetic tunnel junction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Toet, Daniel; Sigmon, Thomas W.</p> <p>2003-01-01</p> <p>A process for direct integration of a thin-film silicon <span class="hlt">p-n</span> junction diode with a magnetic tunnel junction for use in advanced magnetic random access memory (MRAM) cells for high performance, non-volatile memory arrays. The process is based on pulsed laser processing for the fabrication of vertical polycrystalline silicon electronic device structures, in particular <span class="hlt">p-n</span> junction diodes, on films of metals deposited onto low temperature-substrates such as ceramics, dielectrics, glass, or polymers. The process preserves underlayers and structures onto which the devices are typically deposited, such as silicon integrated circuits. The process involves the low temperature deposition of at least one layer of silicon, either in an amorphous or a polycrystalline phase on a metal layer. Dopants may be introduced in the silicon film during or after deposition. The film is then irradiated with short pulse laser energy that is efficiently absorbed in the silicon, which results in the crystallization of the film and simultaneously in the activation of the dopants via ultrafast melting and solidification. The silicon film can be patterned either before or after crystallization.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApPhL.108m3902D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApPhL.108m3902D"><span id="translatedtitle">Efficient thermoelectric energy conversion in Pb0.95Mn0.05Te <span class="hlt">p-n</span> couple</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dybko, K.; Szot, M.; Mycielski, A.; Szczerbakow, A.; Dziawa, P.; Guziewicz, M.; Knoff, W.; Łusakowska, E.; Story, T.</p> <p>2016-03-01</p> <p>We demonstrate an efficient energy conversion in a <span class="hlt">p-n</span> thermoelectric couple built of bulk Pb0.95Mn0.05Te crystals grown by the Bridgman method and heavily doped n-type with Bi ( n =1.9 ×1019cm-3 ) or p-type with Na ( p =2.3 ×1019cm-3 ). Substitution of Mn2+ ions for Pb2+ ions at the rock-salt lattice cation sites increases the band gap of Pb1-xMnxTe and decreases the energy separation between the light hole L-band and the heavy hole Σ-band. It results in a large increase of thermoelectric power and improved thermoelectric parameters of p-type Pb1-xMnxTe. Applying the Harman method for samples of various lengths, we experimentally determined the radiation correction factors and found the thermoelectric figure of merit parameter Z T =0.75 -0.8 at T =650 K for both n- and p-type materials with good thermoelectric matching of the couple. We report on thermoelectric performance of a <span class="hlt">p-n</span> thermoelectric couple assembled of these materials and tested over the T =300 -670 K temperature region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27547841','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27547841"><span id="translatedtitle">Binary Oxide <span class="hlt">p-n</span> Heterojunction Piezoelectric Nanogenerators with an Electrochemically Deposited High p-Type Cu2O Layer.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Baek, Seung Ki; Kwak, Sung Soo; Kim, Joo Sung; Kim, Sang Woo; Cho, Hyung Koun</p> <p>2016-08-31</p> <p>The high performance of ZnO-based piezoelectric nanogenerators (NGs) has been limited due to the potential screening from intrinsic electron carriers in ZnO. We have demonstrated a novel approach to greatly improve piezoelectric power generation by electrodepositing a high-quality p-type Cu2O layer between the piezoelectric semiconducting film and the metal electrode. The <span class="hlt">p-n</span> heterojunction using only oxides suppresses the screening effect by forming an intrinsic depletion region, and thus sufficiently enhances the piezoelectric potential, compared to the pristine ZnO piezoelectric NG. Interestingly, a Sb-doped Cu2O layer has high mobility and low surface trap states. Thus, this doped layer is an attractive p-type material to significantly improve piezoelectric performance. Our results revealed that <span class="hlt">p-n</span> junction NGs consisting of Au/ZnO/Cu2O/indium tin oxide with a Cu2O:Sb (cuprous oxide with a small amount of antimony) layer of sufficient thickness (3 μm) exhibit an extraordinarily high piezoelectric potential of 0.9 V and a maximum output current density of 3.1 μA/cm(2). PMID:27547841</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/18728315','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/18728315"><span id="translatedtitle">Application of a <span class="hlt">pn</span>CCD in X-ray diffraction: a three-dimensional X-ray detector.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Leitenberger, Wolfram; Hartmann, Robert; Pietsch, Ullrich; Andritschke, Robert; Starke, Ines; Strüder, Lothar</p> <p>2008-09-01</p> <p>The first application of a <span class="hlt">pn</span>CCD detector for X-ray scattering experiments using white synchrotron radiation at BESSY II is presented. A Cd arachidate multilayer was investigated in reflection geometry within the energy range 7 keV < E < 35 keV. At fixed angle of incidence the two-dimensional diffraction pattern containing several multilayer Bragg peaks and respective diffuse-resonant Bragg sheets were observed. Since every pixel of the detector is able to determine the energy of every incoming photon with a resolution DeltaE/E approximately 10(-2), a three-dimensional dataset is finally obtained. In order to achieve this energy resolution the detector was operated in the so-called single-photon-counting mode. A full dataset was evaluated taking into account all photons recorded within 10(5) detector frames at a readout rate of 200 Hz. By representing the data in reciprocal-space coordinates, it becomes obvious that this experiment with the <span class="hlt">pn</span>CCD detector provides the same information as that obtained by combining a large number of monochromatic scattering experiments using conventional area detectors. PMID:18728315</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4593177','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4593177"><span id="translatedtitle">Enhancement of the Si <span class="hlt">p-n</span> diode NIR photoresponse by embedding β-FeSi2 nanocrystallites</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Shevlyagin, A. V.; Goroshko, D. L.; Chusovitin, E. A.; Galkin, K. N.; Galkin, N. G.; Gutakovskii, A. K.</p> <p>2015-01-01</p> <p>By using solid phase epitaxy of thin Fe films and molecular beam epitaxy of Si, a p+-Si/p-Si/β-FeSi2 nanocrystallites/n-Si(111) diode structure was fabricated. Transmission electron microscopy data confirmed a well-defined multilayered structure with embedded nanocrystallites of two typical sizes: 3–4 and 15–20 nm, and almost coherent epitaxy of the nanocrystallites with the Si matrix. The diode at zero bias conditions exhibited a current responsivity of 1.7 mA/W, an external quantum efficiency of about 0.2%, and a specific detectivity of 1.2 × 109 cm × Hz1/2/W at a wavelength of 1300 nm at room temperature. In the avalanche mode, the responsivity reached up to 20 mA/W (2% in terms of efficiency) with a value of avalanche gain equal to 5. The data obtained indicate that embedding of β-FeSi2 nanocrystallites into the depletion region of the Si <span class="hlt">p-n</span> junction results in expansion of the spectral sensitivity up to 1600 nm and an increase of the photoresponse by more than two orders of magnitude in comparison with a conventional Si <span class="hlt">p-n</span> junction. Thereby, fabricated structure combines advantage of the silicon photodiode functionality and simplicity with near infrared light detection capability of β-FeSi2. PMID:26434582</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26434582','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26434582"><span id="translatedtitle">Enhancement of the Si <span class="hlt">p-n</span> diode NIR photoresponse by embedding β-FeSi2 nanocrystallites.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Shevlyagin, A V; Goroshko, D L; Chusovitin, E A; Galkin, K N; Galkin, N G; Gutakovskii, A K</p> <p>2015-01-01</p> <p>By using solid phase epitaxy of thin Fe films and molecular beam epitaxy of Si, a p(+)-Si/p-Si/β-FeSi2 nanocrystallites/n-Si(111) diode structure was fabricated. Transmission electron microscopy data confirmed a well-defined multilayered structure with embedded nanocrystallites of two typical sizes: 3-4 and 15-20 nm, and almost coherent epitaxy of the nanocrystallites with the Si matrix. The diode at zero bias conditions exhibited a current responsivity of 1.7 mA/W, an external quantum efficiency of about 0.2%, and a specific detectivity of 1.2 × 10(9) cm × Hz(1/2)/W at a wavelength of 1300 nm at room temperature. In the avalanche mode, the responsivity reached up to 20 mA/W (2% in terms of efficiency) with a value of avalanche gain equal to 5. The data obtained indicate that embedding of β-FeSi2 nanocrystallites into the depletion region of the Si <span class="hlt">p-n</span> junction results in expansion of the spectral sensitivity up to 1600 nm and an increase of the photoresponse by more than two orders of magnitude in comparison with a conventional Si <span class="hlt">p-n</span> junction. Thereby, fabricated structure combines advantage of the silicon photodiode functionality and simplicity with near infrared light detection capability of β-FeSi2. PMID:26434582</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SeScT..31a4001F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SeScT..31a4001F"><span id="translatedtitle">Porous silicon formation by hole injection from a back side <span class="hlt">p+/n</span> junction for electrical insulation applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fèvre, A.; Menard, S.; Defforge, T.; Gautier, G.</p> <p>2016-01-01</p> <p>In this paper, we propose to study the formation of porous silicon (PS) in low doped (1 × 1014 cm-3) n-type silicon through hole injection from a back side <span class="hlt">p+/n</span> junction in the dark. This technique is investigated within the framework of electrical insulation. Three different types of junctions are investigated. The first one is an epitaxial n-type layer grown on p+ doped silicon wafer. The two other junctions are carried out by boron diffusion leading to p+ regions with junction depths of 20 and 115 μm. The resulting PS morphology is a double layer with a nucleation layer (NL) and macropores fully filled with mesoporous material. This result is unusual for low doped n-type silicon. Morphology variations are described depending on the junction formation process, the electrolyte composition, the anodization current density and duration. In order to validate the more interesting industrial potentialities of the <span class="hlt">p+/n</span> injection technique, a comparison is achieved with back side illumination in terms of resulting morphology and experiments confirm comparable results. Electrical characterizations of the double layer, including NL and fully filled macropores, are then performed. To our knowledge, this is the first electrical investigation in low doped n type silicon with this morphology. Compared to the bulk silicon, the measured electrical resistivities are 6-7 orders of magnitude higher at 373 K.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6899689','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/6899689"><span id="translatedtitle">Corn <span class="hlt">yield</span> prediction using climatology</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Duchon, C.E.</p> <p>1986-05-01</p> <p>A method is developed to predict corn <span class="hlt">yield</span> during the growing season using a plant process model (CERES-Maize), current weather data and climatological data. The procedure is to place the current year's daily weather (temperature and precipitation) into the model up to the time the <span class="hlt">yield</span> prediction is to be made and sequences of historical data (one sequence per year) after that time until the end of the growing season to produce <span class="hlt">yield</span> estimates. The mean of the distribution of <span class="hlt">yield</span> estimates is taken as the prediction. The variance associated with a prediction is relatively constant until the time of tassel initiation and then decreases toward zero as the season progresses. As a consequence, perfect weather forecasts reach their peak value between the beginning of ear growth and the beginning of grain fill. The change in the predicted <span class="hlt">yield</span> in response to weather as the growing season progresses is discussed for 1983 and 1976 at Peoria, Illinois. Results are given of an attempt to incorporate 30-day Climate Analytic Center outlooks into the predictive scheme. 21 references, 14 figures, 1 table.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910020892','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910020892"><span id="translatedtitle">A comparative study of <span class="hlt">p(+)n</span> and n(+)p InP solar cells made by a closed ampoule diffusion</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Faur, M.; Faur, M.; Flood, D. J.; Weinberg, I.; Brinker, D. J.; Goradia, C.; Fatemi, N.; Goradia, M.; Thesling, W.</p> <p>1991-01-01</p> <p>The purpose was to demonstrate the possibility of fabricating thermally diffused <span class="hlt">p(+)n</span> InP solar cells having high open-circuit voltage without sacrificing the short circuit current. The <span class="hlt">p(+)n</span> junctions were formed by closed-ampoule diffusion of Cd through a 3 to 5 nm thick anodic or chemical phosphorus-rich oxide cap layer grown on n-InP:S Czochralski LEC grown substrates. For solar cells made by thermal diffusion the <span class="hlt">p(+)n</span> configuration is expected to have a higher efficiency than the n(+)p configuration. It is predicted that the AM0, BOL efficiencies approaching 19 percent should be readily achieved providing that good ohmic front contacts could be realized on the p(+) emitters of thickness lower than 1 micron.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22539133','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22539133"><span id="translatedtitle">Cu2ZnSnS4 (CZTS) nanoparticle based nontoxic and earth-abundant hybrid <span class="hlt">pn</span>-junction solar cells.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Saha, Sudip K; Guchhait, Asim; Pal, Amlan J</p> <p>2012-06-14</p> <p>A heterojunction between a layer of CZTS nanoparticles and a layer of fullerene derivatives forms a <span class="hlt">pn</span>-junction. We have used such an inorganic-organic hybrid <span class="hlt">pn</span>-junction device for solar cell applications. As routes to optimize device performance, interdot separation has been reduced by replacing long-chain ligands of the quantum dots with short-chain ligands and thickness of the CZTS layer has been varied. We have shown that the CZTS-fullerene interface could dissociate photogenerated excitons due to the depletion region formed at the <span class="hlt">pn</span>-junction. From capacitance-voltage characteristics, we have determined the width of the depletion region, and compared it with the parameters of devices based on the components of the heterojunction. The results demonstrate solar cell applications based on nontoxic and earth-abundant materials. PMID:22539133</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880000884','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880000884"><span id="translatedtitle">Effects of electron and proton irradiations on n/p and <span class="hlt">p/n</span> GaAs cells grown by MOCVD</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Weinberg, Irving; Swartz, Clifford K.; Hart, Russell E., Jr.</p> <p>1987-01-01</p> <p>State-of-the-art n/p and <span class="hlt">p/n</span> heteroface GaAs cells, processed by metal organic chemical vapor deposition, were irradiated by 1 MeV electrons and 37 MeV protons and their performance determined as a function of fluence. It was found that the <span class="hlt">p/n</span> cells were more radiation resistant than the n/p cells. The increased loss in the n/p cells was attributed to increases in series resistance and losses in the p-region resulting from the irradiation. The greater loss in fill factor observed for the n/p cells introduces the possibility that the presently observed superiority of the <span class="hlt">p/n</span> cells may not be an intrinsic property of this configuration in GaAs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/15584295','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/15584295"><span id="translatedtitle">Defining and managing sustainable <span class="hlt">yield</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Maimone, Mark</p> <p>2004-01-01</p> <p>Ground water resource management programs are paying increasing attention to the integration of ground water and surface water in the planning process. Many plans, however, show a sophistication in approach and presentation that masks a fundamental weakness in the overall analysis. The plans usually discuss issues of demand and <span class="hlt">yield</span>, yet never directly address a fundamental issue behind the plan--how to define sustainable <span class="hlt">yield</span> of an aquifer system. This paper points out a number of considerations that must be addressed in defining sustainable <span class="hlt">yield</span> in order to make the definition more useful in practical water resource planning studies. These include consideration for the spatial and temporal aspects of the problem, the development of a conceptual water balance, the influence of boundaries and changes in technology on the definition, the need to examine water demand as well as available supply, the need for stakeholder involvement, and the issue of uncertainty in our understanding of the components of the hydrologic system. PMID:15584295</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19920070538&hterms=Recombination&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DRecombination','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19920070538&hterms=Recombination&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DRecombination"><span id="translatedtitle">Evaluation of the minority carrier diffusion length and surface-recombination velocity in GaAs <span class="hlt">p/n</span> solar cells</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hakimzadeh, Roshanak; Moeller, Hans J.; Bailey, Sheila</p> <p>1991-01-01</p> <p>The minority carrier diffusion length (Lp) and the surface recombination velocity (Vs) were measured as a function of distance (x) from the <span class="hlt">p-n</span> junction in GaAs <span class="hlt">p/n</span> concentrator solar cells. The measured Vs values were used in a theoretical expression for the normalized electron-beam-induced current. A fitting procedure was then used to fit this expression with experimental values to obtain Lp. The results show that both Vs and Lp vary with x. Lp measured in irradiated cells showed a marked reduction. These values were compared to those measured previously which did not account for Vs.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <center> <div class="footer-extlink text-muted"><small>Some links on this page may take you to non-federal websites. Their policies may differ from this site.</small> </div> </center> <div id="footer-wrapper"> <div class="footer-content"> <div id="footerOSTI" class=""> <div class="row"> <div class="col-md-4 text-center col-md-push-4 footer-content-center"><small><a href="http://www.science.gov/disclaimer.html">Privacy and Security</a></small> <div class="visible-sm visible-xs push_footer"></div> </div> <div class="col-md-4 text-center col-md-pull-4 footer-content-left"> <img src="http://www.osti.gov/images/DOE_SC31.png" alt="U.S. Department of Energy" usemap="#doe" height="31" width="177"><map style="display:none;" name="doe" id="doe"><area shape="rect" coords="1,3,107,30" href="http://www.energy.gov" alt="U.S. Deparment of Energy"><area shape="rect" coords="114,3,165,30" href="http://www.science.energy.gov" alt="Office of Science"></map> <a ref="http://www.osti.gov" style="margin-left: 15px;"><img src="http://www.osti.gov/images/footerimages/ostigov53.png" alt="Office of Scientific and Technical Information" height="31" width="53"></a> <div class="visible-sm visible-xs push_footer"></div> </div> <div class="col-md-4 text-center footer-content-right"> <a href="http://www.osti.gov/nle"><img src="http://www.osti.gov/images/footerimages/NLElogo31.png" alt="National Library of Energy" height="31" width="79"></a> <a href="http://www.science.gov"><img src="http://www.osti.gov/images/footerimages/scigov77.png" alt="science.gov" height="31" width="98"></a> <a href="http://worldwidescience.org"><img src="http://www.osti.gov/images/footerimages/wws82.png" alt="WorldWideScience.org" height="31" width="90"></a> </div> </div> </div> </div> </div> <p><br></p> </div><!-- container --> </body> </html>