Rigid thin windows for vacuum applications
Meyer, Glenn Allyn; Ciarlo, Dino R.; Myers, Booth Richard; Chen, Hao-Lin; Wakalopulos, George
1999-01-01
A thin window that stands off atmospheric pressure is fabricated using photolithographic and wet chemical etching techniques and comprises at least two layers: an etch stop layer and a protective barrier layer. The window structure also comprises a series of support ribs running the width of the window. The windows are typically made of boron-doped silicon and silicon nitride and are useful in instruments such as electron beam guns and x-ray detectors. In an electron beam gun, the window does not impede the electrons and has demonstrated outstanding gun performance and survivability during the gun tube manufacturing process.
High-resolution crystal spectrometer for the 10-60 A extreme ultraviolet region
DOE Office of Scientific and Technical Information (OSTI.GOV)
Beiersdorfer, P.; Brown, G.V.; Goddard, R.
2004-10-01
A vacuum crystal spectrometer with nominal resolving power approaching 1000 is described for measuring emission lines with wavelength in the extreme ultraviolet region up to 60 A. The instrument utilizes a flat octadecyl hydrogen maleate crystal and a thin-window 1D position-sensitive gas proportional detector. This detector employs a 1-{mu}m-thick 100x8 mm{sup 2} aluminized polyimide window and operates at one atmosphere pressure. The spectrometer has been implemented on the Livermore electron beam ion traps. The performance of the instrument is illustrated in measurements of the newly discovered magnetic field-sensitive line in Ar{sup 8+}.
High-resolution crystal spectrometer for the 10-60 (angstrom) EUV region
DOE Office of Scientific and Technical Information (OSTI.GOV)
Beiersdorfer, P; Brown, G V; Goddard, R
2004-02-20
A vacuum crystal spectrometer with nominal resolving power approaching 1000 is described for measuring emission lines with wavelength in the extreme ultraviolet region up to 60 Angstroms. The instrument utilizes a flat octadecyl hydrogen maleate (OHM) crystal and a thin-window 1-D position-sensitive gas proportional detector. This detector employs a 1 {micro}m-thick 100 x8 mm{sup 2} aluminized polyimide window and operates at one atmosphere pressure. The spectrometer has been implemented on the Livermore electron beam ion traps. The performance of the instrument is illustrated in measurements of the newly discovered magnetic field-sensitive line in Ar{sup 8+}.
Thinning and mounting a Texas Instruments 3-phase CCD
NASA Technical Reports Server (NTRS)
Lesser, M. P.; Leach, R. W.; Angel, J. R. P.
1986-01-01
Thin CCDs with precise control of thickness and surface quality allow astronomers to optimize chips for specific applications. A means of mechanically thinning a TI 800 x 800 CCD with an abrasive slurry of aluminum oxide is presented. Using the same techniques, the abrasives can be replaced with a chemical solution to eliminate subsurface damage. A technique of mounting the CCD which retains the high quality surface generated during thinning is also demonstrated. This requires the backside of the chip to be bonded to a glass window which closely matches silicon's thermal expansion properties. Thinned CCDs require backside treatment to enhance blue and UV quantum efficiency. Two methods are discussed which may be effective with this mounting system.
Computer Controlled Magnetotransport Setup for the Characterization of Semiconductor Thin Films
NASA Technical Reports Server (NTRS)
Ducoudray, G. O.; Collazo, R.; Martinez, A.
1997-01-01
We have considered a computer controlled magnetotransport setup using LabWindows environment. It allows for measurements of resistivity, Hall resistance, carrier concentration and charge mobility in semiconductor thin films using a van der Pauw configuration. The setup features an electromagnet (B = 0.7 Tesla) a 80486-DX 33 computer with a National Instrument AT-MIO 16 AD/DA and a GPIB interface board. A Keithely 224 current source and a Keithley 196 digital voltmeter were also used in the setup. Plans for the addition of capabilities to allow for magnetic field sweeping and the performance of measurements as a function of temperature will be presented.
NASA Astrophysics Data System (ADS)
Marquis, Jared Wayne
Passive longwave infrared radiometric satellite-based retrievals of sea surface temperature (SST) at instrument nadir are investigated for cold bias caused by unscreened optically-thin cirrus (OTC) clouds (cloud optical depth ≤ 0.3; COD). Level 2 split-window SST retrievals over tropical oceans (30° S - 30° N) from Moderate Resolution Imaging Spectroradiometer (MODIS) radiances collected aboard the NASA Aqua satellite (Aqua-MODIS) are collocated with cloud profiles from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) instrument, mounted on the independent NASA CALIPSO satellite. OTC are present in approximately 25% of tropical quality-assured (QA) Aqua-MODIS Level-2 data, representing over 99% of all contaminating cirrus found. This results in cold-biased SST retrievals using either split- (MODIS, AVHRR and VIIRS) or triple-window (AVHRR and VIIRS only) retrieval methods. SST retrievals are modeled based on operational algorithms using radiative transfer model simulations conducted with a hypothetical 1.5 km thick OTC cloud placed incrementally from 10.0 - 18.0 km above mean sea level for cloud optical depths (COD) between 0.0 - 0.3. Corresponding cold bias estimates for each sensor are estimated using relative Aqua-MODIS cloud contamination frequencies as a function of cloud top height and COD (assuming them consistent across each platform) integrated within each corresponding modeled cold bias matrix. Split-window relative OTC cold biases, for any single observation, range from 0.40° - 0.49° C for the three sensors, with an absolute (bulk mean) bias between 0.10° - 0.13° C. Triple-window retrievals are more resilient, ranging from 0.03° - 0.04° C relative and 0.11° - 0.16° C absolute. Cold biases are constant across the Pacific and Indian Ocean domains. Absolute bias is smaller over the Atlantic, but relative bias is larger due to different cloud properties indicating that this issue persists globally.
Wang, Ruikang K.
2014-01-01
In vivo imaging of mouse brain vasculature typically requires applying skull window opening techniques: open-skull cranial window or thinned-skull cranial window. We report non-invasive 3D in vivo cerebral blood flow imaging of C57/BL mouse by the use of ultra-high sensitive optical microangiography (UHS-OMAG) and Doppler optical microangiography (DOMAG) techniques to evaluate two cranial window types based on their procedures and ability to visualize surface pial vessel dynamics. Application of the thinned-skull technique is found to be effective in achieving high quality images for pial vessels for short-term imaging, and has advantages over the open-skull technique in available imaging area, surgical efficiency, and cerebral environment preservation. In summary, thinned-skull cranial window serves as a promising tool in studying hemodynamics in pial microvasculature using OMAG or other OCT blood flow imaging modalities. PMID:25426632
High Tech Art: Chameleon Glass
NASA Technical Reports Server (NTRS)
1993-01-01
Dichroic Glass is a technology wherein extremely thin films of metal are vacuum deposited on a glass surface. The coated glass shields spacecraft instruments from cosmic radiation and protects human vision from unfiltered sunlight in space. Because the coating process allows some wavelengths of light and color to reflect and others to pass through, a chameleon effect is produced. Murray Schwartz, a former aerospace engineer, has based his business KROMA on this NASA optical technology. He produces dichroic stained glass windows, mobiles and jewelry. The technique involves deposition of super thin layers of metal oxides applied one layer at a time in a specific order and thickness for the desired effect. His product line is unique and has been very successful.
NASA Technical Reports Server (NTRS)
Azzam, R. M. A. (Editor); Coffeen, D. L.
1977-01-01
Instrumentation used in optical polarimetry is discussed with reference to high-resolution spectropolarimetry, an orbiter cloud photopolarimeter, X-ray polarimeters, and the design of a self-nulling ellipsometer. Consideration is given to surface and thin-film ellipsometry noting studies of electrochemical surface layers, surface anisotropy, polish layers on infrared window materials, and anodic films. Papers on biological, chemical, and physical polarimetry are presented including birefringence in biological materials, vibrational optical activity, and the optical determination of the thermodynamic phase diagram of a metamagnet. Remote sensing is discussed in terms of polarization imagery, the optical polarimetry of particulate surfaces, and techniques and applications of elliptical polarimetry in astronomy and atmospheric studies.
Modeling and experimental investigation of x-ray spectra from a liquid metal anode x-ray tube
NASA Astrophysics Data System (ADS)
David, Bernd R.; Thran, Axel; Eckart, Rainer
2004-11-01
This paper presents simulated and measured spectra of a novel type of x-ray tube. The bremsstrahlung generating principle of this tube is based on the interaction of high energetic electrons with a turbulently flowing liquid metal separated from the vacuum by a thin window. We simulated the interaction of 50-150 keV electrons with liquid metal targets composed of the elements Ga, In, Sn, as well as the solid elements C, W and Re used for the electron windows. We obtained x-ray spectra and energy loss curves for various liquid metal/window combinations and thicknesses of the window material. In terms of optimum heat transport a thin diamond window in combination with the liquid metal GaInSn is the best suited system. If photon flux is the optimization criteria, thin tungsten/rhenium windows cooled by GaInSn should be preferred.
NASA Astrophysics Data System (ADS)
Shvetsov, V. N.; Dubasov, P. V.; Golovin, D. V.; Kozyrev, A. S.; Krylov, A. R.; Krylov, V. A.; Litvak, M. L.; Malakhov, A. V.; Mitrofanov, I. G.; Mokrousov, M. I.; Sanin, A. B.; Timoshenko, G. N.; Vostrukhin, A. A.; Zontikov, A. O.
2017-07-01
The results of the Dynamic Albedo of Neutrons (DAN) instrument ground tests in the passive mode of operation are presented in comparison with the numerical calculations. These test series were conducted to support the current surface measurements of DAN onboard the MSL Curiosity rover. The instrument sensitivity to detect thin subsurface layers of water ice buried at different depths in the analog of Martian soil has been evaluated during these tests. The experiments have been done with a radioisotope Pu-Be neutron source (analog of the MMRTG neutron source onboard the Curiosity rover) and the Martian soil model assembled from silicon-rich window glass pane. Water ice layers were simulated with polyethylene sheets. All experiments have been performed at the test facility built at the Joint Institute for Nuclear Research (Dubna, Russia).
Electrolyte and Electrode Passivation for Thin Film Batteries
NASA Technical Reports Server (NTRS)
West, W.; Whitacre, J.; Ratnakumar, B.; Brandon, E.; Blosiu, J.; Surampudi, S.
2000-01-01
Passivation films for thin film batteries have been prepared and the conductivity and voltage stability window have been measured. Thin films of Li2CO3 have a large voltage stability window of 4.8V, which facilitates the use of this film as a passivation at both the lithium anode-electrolyte interface at high cathodic potentials.
Radiological Defense. Volume 4. An Introduction to Radiological Instruments for Military Use
1950-01-01
alpha admission. Thin mica and stretched nylon walls with nonmetals of low atomic number and and rubber hydrochloride films about 5 microns writing...individual pulse. This process is called qu •,cIh1ng and can be ac- R, 5ME.OH, , • .. complished by using external electronic methods ’-""::_:-:Ž-:- " or...counter tubes field survey work. Mica windows down to 0.5 )resentliy employed in survey meters are " inch in mg/cm 2 are available, although in normal
Landsat-5 Thematic Mapper outgassing effects
Helder, D.L.; Micijevic, E.
2004-01-01
A periodic 3% to 5% variation in detector response affecting both image and internal calibrator (IC) data has been observed in bands 5 and 7 of the Landsat-5 Thematic Mapper. The source for this variation is thought to be an interference effect due to buildup of an ice-like contaminant film on a ZnSe window, covered with an antireflective coating (ARC), of the cooled dewar containing these detectors. Periodic warming of the dewar is required in order to remove the contaminant and restore detector response to an uncontaminated level. These effects in the IC data have been characterized over four individual outgassing cycles using thin-film models to estimate transmittance of the window/ARC and ARC/contaminant film stack throughout the instrument lifetime. Based on the results obtained from this modeling, a lookup table procedure has been implemented that provides correction factors to improve the calibration accuracy of bands 5 and 7 by approximately 5%.
Method for preparing dosimeter for measuring skin dose
Jones, Donald E.; Parker, DeRay; Boren, Paul R.
1982-01-01
A personnel dosimeter includes a plurality of compartments containing thermoluminescent dosimeter phosphors for registering radiation dose absorbed in the wearer's sensitive skin layer and for registering more deeply penetrating radiation. Two of the phosphor compartments communicate with thin windows of different thicknesses to obtain a ratio of shallowly penetrating radiation, e.g. beta. A third phosphor is disposed within a compartment communicating with a window of substantially greater thickness than the windows of the first two compartments for estimating the more deeply penetrating radiation dose. By selecting certain phosphors that are insensitive to neutrons and by loading the holder material with neutron-absorbing elements, energetic neutron dose can be estimated separately from other radiation dose. This invention also involves a method of injection molding of dosimeter holders with thin windows of consistent thickness at the corresponding compartments of different holders. This is achieved through use of a die insert having the thin window of precision thickness in place prior to the injection molding step.
Dosimeter for measuring skin dose and more deeply penetrating radiation
Jones, Donald E.; Parker, DeRay; Boren, Paul R.
1981-01-01
A personnel dosimeter includes a plurality of compartments containing thermoluminescent dosimeter phosphors for registering radiation dose absorbed in the wearer's sensitive skin layer and for registering more deeply penetrating radiation. Two of the phosphor compartments communicate with thin windows of different thicknesses to obtain a ratio of shallowly penetrating radiation, e.g. beta. A third phosphor is disposed within a compartment communicating with a window of substantially greater thickness than the windows of the first two compartments for estimating the more deeply penetrating radiation dose. By selecting certain phosphors that are insensitive to neutrons and by loading the holder material with netruon-absorbing elements, energetic neutron dose can be estimated separately from other radiation dose. This invention also involves a method of injection molding of dosimeter holders with thin windows of consistent thickness at the corresponding compartments of different holders. This is achieved through use of a die insert having the thin window of precision thickness in place prior to the injection molding step.
Ceglio, N.M.; Stearns, D.G.; Hawryluk, A.M.; Barbee, T.W. Jr.
1987-08-07
An x-ray beamsplitter which splits an x-ray beam into two coherent parts by reflecting and transmitting some fraction of an incident beam has applications for x-ray interferometry, x-ray holography, x-ray beam manipulation, and x-ray laser cavity output couplers. The beamsplitter is formed of a wavelength selective multilayer thin film supported by a very thin x-ray transparent membrane. The beamsplitter resonantly transmits and reflects x-rays through thin film interference effects. A thin film is formed of 5--50 pairs of alternate Mo/Si layers with a period of 20--250 A. The support membrane is 10--200 nm of silicon nitride or boron nitride. The multilayer/support membrane structure is formed across a window in a substrate by first forming the structure on a solid substrate and then forming a window in the substrate to leave a free-standing structure over the window. 6 figs.
Ceglio, Natale M.; Stearns, Daniel S.; Hawryluk, Andrew M.; Barbee, Jr., Troy W.
1989-01-01
An x-ray beamsplitter which splits an x-ray beam into two coherent parts by reflecting and transmitting some fraction of an incident beam has applications for x-ray interferometry, x-ray holography, x-ray beam manipulation, and x-ray laser cavity output couplers. The beamsplitter is formed of a wavelength selective multilayer thin film supported by a very thin x-ray transparent membrane. The beamsplitter resonantly transmits and reflects x-rays through thin film interference effects. A thin film is formed of 5-50 pairs of alternate Mo/Si layers with a period of 20-250 A. The support membrane is 10-200 nm of silicon nitride or boron nitride. The multilayer/support membrane structure is formed across a window in a substrate by first forming the structure on a solid substrate and then forming a window in the substrate to leave a free-standing structure over the window.
Cooled optical filters for Q-band infrared astronomy (15-40 μm)
NASA Astrophysics Data System (ADS)
Hawkins, Gary J.; Sherwood, Richard E.; Djotni, Karim; Threadgold, Timothy M.
2016-07-01
With a growing interest in mid- and far-infrared astronomy using cooled imaging and spectrometer instruments in highaltitude observatories and spaceflight telescopes, it is becoming increasingly important to characterise and assess the spectral performance of cooled multilayer filters across the Q-band atmospheric window. This region contains spectral features emitted by many astrophysical phenomena and objects fundamental to circumstellar and planetary formation theories. However extending interference filtering to isolate radiation at progressively longer wavelengths and improve photometric accuracy is an area of ongoing and challenging thin-film research. We have successfully fabricated cooled bandpass and edge filters with high durability for operation across the 15-30 μm Q-band region. In this paper we describe the rationale for selection of optical materials and properties of fabricated thin-film coatings for this region, together with FTIR spectral measurements and assessment of environmental durability.
The opto-cryo-mechanical design of the short wavelength camera for the CCAT Observatory
NASA Astrophysics Data System (ADS)
Parshley, Stephen C.; Adams, Joseph; Nikola, Thomas; Stacey, Gordon J.
2014-07-01
The CCAT observatory is a 25-m class Gregorian telescope designed for submillimeter observations that will be deployed at Cerro Chajnantor (~5600 m) in the high Atacama Desert region of Chile. The Short Wavelength Camera (SWCam) for CCAT is an integral part of the observatory, enabling the study of star formation at high and low redshifts. SWCam will be a facility instrument, available at first light and operating in the telluric windows at wavelengths of 350, 450, and 850 μm. In order to trace the large curvature of the CCAT focal plane, and to suit the available instrument space, SWCam is divided into seven sub-cameras, each configured to a particular telluric window. A fully refractive optical design in each sub-camera will produce diffraction-limited images. The material of choice for the optical elements is silicon, due to its excellent transmission in the submillimeter and its high index of refraction, enabling thin lenses of a given power. The cryostat's vacuum windows double as the sub-cameras' field lenses and are ~30 cm in diameter. The other lenses are mounted at 4 K. The sub-cameras will share a single cryostat providing thermal intercepts at 80, 15, 4, 1 and 0.1 K, with cooling provided by pulse tube cryocoolers and a dilution refrigerator. The use of the intermediate temperature stage at 15 K minimizes the load at 4 K and reduces operating costs. We discuss our design requirements, specifications, key elements and expected performance of the optical, thermal and mechanical design for the short wavelength camera for CCAT.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, G. V.; Beiersdorfer, P.; Goddard, R.
2001-01-01
We have mounted 1 {mu}m thick aluminized polyimide windows onto the position sensitive proportional counters employed by the wide-band flat crystal spectrometers at the Lawrence Livermore National Laboratory electron beam ion trap experiment. The aluminized polyimide, supported by thin wires across the short axis of the window, is used to isolate the detection chamber of the proportional counters, which operate at a pressure of 760 Torr, from the vacuum chamber of the spectrometer. The windows are modified versions of those developed for the proportional counters which were used during ground calibration of the Chandra X-ray Observatory. The transmission properties ofmore » these windows are, therefore, well known. The increased transmission efficiency of the polyimide windows relative to the 4 {mu}m thick polypropylene window material previously employed by our proportional counters has extended the useful range of the spectrometer from roughly 20 to 30 Aa at energies below the carbon edge, as well as increasing detection efficiency at wavelengths beyond the carbon edge. Using an octadecyl hydrogen maleate crystal with 2d=63.5Aa, we demonstrate the increased wavelength coverage by measuring the resonance, intercombination, and forbidden lines in helium-like NVII in two different density regimes. The thin polyimide windows have also increased the efficiency of the spectrometers entire wavelength range. To demonstrate the increased efficiency we compare the FeXVII spectrum in the 15--17 Aa band measured with the 1 {mu}m aluminized polyimide windows to the 4 {mu}m aluminized polypropylene windows. The comparison shows an average increase in efficiency of {approx}40%. The polyimide windows have a significantly lower leak rate than the polypropylene windows making it possible to achieve approximately an order of magnitude lower pressure in the spectrometer vacuum chamber which reduces the gas load on the trap region.« less
A composite thin vacuum window for the CLAS photon tagger at Jefferson lab
NASA Astrophysics Data System (ADS)
Matthews, S. K.; Crannell, Hall; O'Brien, J. T.; Sober, D. I.
1999-01-01
The construction of a thin vacuum window, currently in use on the CLAS photon tagging system at the Thomas Jefferson National Accelerator Facility, is described. A layer of woven Kevlar cloth supports a much thinner membrane of aluminized Mylar. Notable features of this particular window include its overall length (9.6 m), and the fact that the entire load is supported by the epoxy seal with no mechanical clamping around the edges. Results from a diverse program of materials testing, including a clear dependence of leak rate on relative humidity, are also reported.
Structural studies of n-type nc-Si-QD thin films for nc-Si solar cells
NASA Astrophysics Data System (ADS)
Das, Debajyoti; Kar, Debjit
2017-12-01
A wide optical gap nanocrystalline silicon (nc-Si) dielectric material is a basic requirement at the n-type window layer of nc-Si solar cells in thin film n-i-p structure on glass substrates. Taking advantage of the high atomic-H density inherent to the planar inductively coupled low-pressure (SiH4 + CH4)-plasma, development of an analogous material in P-doped nc-Si-QD/a-SiC:H network has been tried. Incorporation of C in the Si-network extracted from the CH4 widens the optical band gap; however, at enhanced PH3-dilution of the plasma spontaneous miniaturization of the nc-Si-QDs below the dimension of Bohr radius (∼4.5 nm) further enhances the band gap by virtue of the quantum size effect. At increased flow rate of PH3, dopant induced continuous amorphization of the intrinsic crystalline network is counterbalanced by the further crystallization promoted by the supplementary atomic-H extracted from PH3 (1% in H2) in the plasma, eventually holding a moderately high degree of crystallinity. The n-type wide band gap (∼1.93 eV) window layer with nc-Si-QDs in adequate volume fraction (∼52%) could furthermore be instrumental as an effective seed layer for advancing sequential crystallization in the i-layer of nc-Si solar cells with n-i-p structure in superstrate configuration.
Radiation-transparent windows, method for imaging fluid transfers
Shu, Deming [Darien, IL; Wang, Jin [Burr Ridge, IL
2011-07-26
A thin, x-ray-transparent window system for environmental chambers involving pneumatic pressures above 40 bar is presented. The window allows for x-ray access to such phenomena as fuel sprays injected into a pressurized chamber that mimics realistic internal combustion engine cylinder operating conditions.
Thin and open vessel windows for intra-vital fluorescence imaging of murine cochlear blood flow
Shi, Xiaorui; Zhang, Fei; Urdang, Zachary; Dai, Min; Neng, Lingling; Zhang, Jinhui; Chen, Songlin; Ramamoorthy, Sripriya; Nuttall, Alfred L.
2014-01-01
Normal microvessel structure and function in the cochlea is essential for maintaining the ionic and metabolic homeostasis required for hearing function. Abnormal cochlear microcirculation has long been considered an etiologic factor in hearing disorders. A better understanding of cochlear blood flow (CoBF) will enable more effective amelioration of hearing disorders that result from aberrant blood flow. However, establishing the direct relationship between CoBF and other cellular events in the lateral wall and response to physio-pathological stress remains a challenge due to the lack of feasible interrogation methods and difficulty in accessing the inner ear. Here we report on new methods for studying the CoBF in a mouse model using a thin or open vessel-window in combination with fluorescence intra-vital microscopy (IVM). An open vessel-window enables investigation of vascular cell biology and blood flow permeability, including pericyte (PC) contractility, bone marrow cell migration, and endothelial barrier leakage, in wild type and fluorescent protein-labeled transgenic mouse models with high spatial and temporal resolution. Alternatively, the thin vessel-window method minimizes disruption of the homeostatic balance in the lateral wall and enables study CoBF under relatively intact physiological conditions. A thin vessel-window method can also be used for time-based studies of physiological and pathological processes. Although the small size of the mouse cochlea makes surgery difficult, the methods are sufficiently developed for studying the structural and functional changes in CoBF under normal and pathological conditions. PMID:24780131
Diamond X-ray Photodiode for White and Monochromatic SR beams
Keister, Jeffrey W.; Smedley, John; Muller, Erik M.; Bohon, Jen; Héroux, Annie
2011-01-01
High purity, single crystal CVD diamond plates are screened for quality and instrumented into a sensor assembly for quantitative characterization of flux and position sensitivity. Initial investigations have yielded encouraging results and have led to further development. Several limiting complications are observed and discussed, as well as mitigations thereof. For example, diamond quality requirements for x-ray diodes include low nitrogen impurity and crystallographic defectivity. Thin electrode windows and electronic readout performance are ultimately also critical to device performance. Promising features observed so far from prototype devices include calculable responsivity, flux linearity, position sensitivity and timing performance. Recent results from testing in high flux and high speed applications are described. PMID:21822344
Thin and open vessel windows for intra-vital fluorescence imaging of murine cochlear blood flow.
Shi, Xiaorui; Zhang, Fei; Urdang, Zachary; Dai, Min; Neng, Lingling; Zhang, Jinhui; Chen, Songlin; Ramamoorthy, Sripriya; Nuttall, Alfred L
2014-07-01
Normal microvessel structure and function in the cochlea is essential for maintaining the ionic and metabolic homeostasis required for hearing function. Abnormal cochlear microcirculation has long been considered an etiologic factor in hearing disorders. A better understanding of cochlear blood flow (CoBF) will enable more effective amelioration of hearing disorders that result from aberrant blood flow. However, establishing the direct relationship between CoBF and other cellular events in the lateral wall and response to physio-pathological stress remains a challenge due to the lack of feasible interrogation methods and difficulty in accessing the inner ear. Here we report on new methods for studying the CoBF in a mouse model using a thin or open vessel-window in combination with fluorescence intra-vital microscopy (IVM). An open vessel-window enables investigation of vascular cell biology and blood flow permeability, including pericyte (PC) contractility, bone marrow cell migration, and endothelial barrier leakage, in wild type and fluorescent protein-labeled transgenic mouse models with high spatial and temporal resolution. Alternatively, the thin vessel-window method minimizes disruption of the homeostatic balance in the lateral wall and enables study CoBF under relatively intact physiological conditions. A thin vessel-window method can also be used for time-based studies of physiological and pathological processes. Although the small size of the mouse cochlea makes surgery difficult, the methods are sufficiently developed for studying the structural and functional changes in CoBF under normal and pathological conditions. Copyright © 2014 Elsevier B.V. All rights reserved.
InP solar cell with window layer
NASA Technical Reports Server (NTRS)
Jain, Raj K. (Inventor); Landis, Geoffrey A. (Inventor)
1994-01-01
The invention features a thin light transmissive layer of the ternary semiconductor indium aluminum arsenide (InAlAs) as a front surface passivation or 'window' layer for p-on-n InP solar cells. The window layers of the invention effectively reduce front surface recombination of the object semiconductors thereby increasing the efficiency of the cells.
Hayes, P.M.
1960-02-16
A beta particle counter adapted to use an end window made of polyethylene terephthalate was designed. The extreme thinness of the film results in a correspondingly high transmission of incident low-energy beta particles by the window. As a consequence, the counting efficiency of the present counter is over 40% greater than counters using conventional mica end windows.
Liquid-phase deposition of thin Si films by ballistic electro-reduction
NASA Astrophysics Data System (ADS)
Ohta, T.; Gelloz, B.; Kojima, A.; Koshida, N.
2013-01-01
It is shown that the nanocryatalline silicon ballistic electron emitter operates in a SiCl4 solution without using any counter electrodes and that thin amorphous Si films are efficiently deposited on the emitting surface with no contaminations and by-products. Despite the large electrochemical window of the SiCl4 solution, electrons injected with sufficiently high energies preferentially reduce Si4+ ions at the interface. Using an emitter with patterned line emission windows, a Si-wires array can be formed in parallel. This low-temperature liquid-phase deposition technique provides an alternative clean process for power-effective fabrication of advanced thin Si film structures and devices.
Transparent and flexible heaters based on Al:ZnO degenerate semiconductor
NASA Astrophysics Data System (ADS)
Roul, Monee K.; Obasogie, Brandon; Kogo, Gilbert; Skuza, J. R.; Mundle, R. M.; Pradhan, A. K.
2017-10-01
We report on high performance transparent Al:ZnO (AZO) thin film heaters on flexible polymer (polyethylene terephthalate) and glass substrates which demonstrate low sheet resistivity. AZO thin films were grown by radio-frequency magnetron sputtering at low Ts (below 200 °C) on flexible, transparent polyethylene terephthalate substrates that show stable and reproducible results by applying low (<10 V) voltages. This study also examined identical AZO thin films on glass substrates that showed highly reproducible heating effects due to the Joule heating effect. The potential applications are foldable and wearable electronics, pain/injury therapy smart windows, automobile window defrosters, and low-cost power electronics.
Overview of Fabrication Techniques and Lessons Learned with Accelerator Vacuum Windows
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ader, C. R.; McGee, M. W.; Nobrega, L. E.
Vacuum thin windows have been used in Fermilab's accelerators for decades and typically have been overlooked in terms of their criticality and fragility. Vacuum windows allow beam to pass through while creating a boundary between vacuum and air or high vacuum and low vacuum areas. The design of vacuum windows, including Titanium and Beryllium windows, will be discussed as well as fabrication, testing, and operational concerns. Failure of windows will be reviewed as well as safety approaches to mitigating failures and extending the lifetimes of vacuum windows. Various methods of calculating the strengths of vacuum windows will be explored, includingmore » FEA.« less
Note: reliable and reusable ultrahigh vacuum optical viewports.
Arora, P; Sen Gupta, A
2012-04-01
We report a simple technique for the realization of ultrahigh vacuum optical viewports. The technique relies on using specially designed thin copper knife-edges and using a thin layer of Vacseal(®) on tip of the knife-edges between the optical flat and the ConFlat(®) (CF) flange. The design of the windows is such that it gives uniform pressure on the flat without breaking it. The assembled window is a complete unit, which can be mounted directly onto a CF flange of the vacuum chamber. It can be removed and reused without breaking the window seal. The design is reliable as more than a dozen such windows have survived several bake out and cooling cycles and have been leak tested up to 10(-11) Torr l/s level with a commercial Helium leak detector. The advantages of this technique are ease of assembly and leak proof sealing that survives multiple temperature cycling making the windows reliable and reusable. © 2012 American Institute of Physics
Counter tube window and X-ray fluorescence analyzer study
NASA Technical Reports Server (NTRS)
Hertel, R.; Holm, M.
1973-01-01
A study was performed to determine the best design tube window and X-ray fluorescence analyzer for quantitative analysis of Venusian dust and condensates. The principal objective of the project was to develop the best counter tube window geometry for the sensing element of the instrument. This included formulation of a mathematical model of the window and optimization of its parameters. The proposed detector and instrument has several important features. The instrument will perform a near real-time analysis of dust in the Venusian atmosphere, and is capable of measuring dust layers less than 1 micron thick. In addition, wide dynamic measurement range will be provided to compensate for extreme variations in count rates. An integral pulse-height analyzer and memory accumulate data and read out spectra for detail computer analysis on the ground.
Thin film absorber for a solar collector
Wilhelm, William G.
1985-01-01
This invention pertains to energy absorbers for solar collectors, and more particularly to high performance thin film absorbers. The solar collectors comprising the absorber of this invention overcome several problems seen in current systems, such as excessive hardware, high cost and unreliability. In the preferred form, the apparatus features a substantially rigid planar frame with a thin film window bonded to one planar side of the frame. An absorber in accordance with the present invention is comprised of two thin film layers that are sealed perimetrically. In a preferred embodiment, thin film layers are formed from a metal/plastic laminate. The layers define a fluid-tight planar envelope of large surface area to volume through which a heat transfer fluid flows. The absorber is bonded to the other planar side of the frame. The thin film construction of the absorber assures substantially full envelope wetting and thus good efficiency. The window and absorber films stress the frame adding to the overall strength of the collector.
Demand-type gas supply system for rocket borne thin-window proportional counters
NASA Technical Reports Server (NTRS)
Acton, L. W.; Caravalho, R.; Catura, R. C.; Joki, E. G.
1977-01-01
A simple closed loop control system has been developed to maintain the gas pressure in thin-window proportional counters during rocket flights. This system permits convenient external control of detector pressure and system flushing rate. The control system is activated at launch with the sealing of a reference volume at the existing system pressure. Inflight control to plus or minus 2 torr at a working pressure of 760 torr has been achieved on six rocket flights.
NASA Astrophysics Data System (ADS)
Ferkinhoff, Carl; Hershey, Deborah; Scrabeck, Alex; Higdon, Sarah; Higdon, James L.; Tidwell, Hannah; Lamarche, Cody; Vishwas, Amit; Nikola, Thomas; Stacey, Gordon J.; Brisbin, Drew
2018-06-01
Galaxies have evolved significantly from the early Universe until today. Star formation rates, stellar and molecular gas masses, sizes and metal enrichment of galaxies have all changed significantly from early epochs until the present. Probing the physical conditions of galaxy at high redshift is vital to understanding this evolution. ZINGRS, the ZEUS 1 and 2 INvestigated Galaxy Reference Sample, provides a unique and powerful window for this work. The sample consists of more than ~30 galaxies from z ~ 1 - 4.5 for which the far-IR fine-structure lines (e.g. [CII] 158 micron, [NII] 122micron, [OIII] 88 micron) have been observed with the ZEUS-1 and 2 instruments. These lines are ideal for studying high-z systems since they require low energies for excitation, are typically optically thin, and are not susceptible to extinction from dust. ZINGRS is the largest collection of far-IR fine-structure line detections at high-z. Here we describe the sample, including extensive multifrequency supporting observations like CO & radio continuum, and summarize what we have learned so far.
Wilhelm, W.G.
The invention pertains to a flat plate collector that employs high performance thin films. The solar collector of this invention overcomes several problems in this field, such as excessive hardware, cost and reliability, and other prior art drawbacks outlined in the specification. In the preferred form, the apparatus features a substantially rigid planar frame. A thin film window is bonded to one planar side of the frame. An absorber of laminate construction is comprised of two thin film layers that are sealed perimetrically. The layers define a fluid-tight planar envelope of large surface area to volume through which a heat transfer fluid flows. Absorber is bonded to the other planar side of the frame. The thin film construction of the absorber assures substantially full envelope wetting and thus good efficiency. The window and absorber films stress the frame adding to the overall strength of the collector.
Breaking through with Thin-Client Technologies: A Cost Effective Approach for Academic Libraries.
ERIC Educational Resources Information Center
Elbaz, Sohair W.; Stewart, Christofer
This paper provides an overview of thin-client/server computing in higher education. Thin-clients are like PCs in appearance, but they do not house hard drives or localized operating systems and cannot function without being connected to a server. Two types of thin-clients are described: the Network Computer (NC) and the Windows Terminal (WT).…
On the size and composition of particles in polar stratospheric clouds
NASA Technical Reports Server (NTRS)
Kinne, Stefan; Toon, Owen B.; Toon, Goeff C.; Farmer, Crofton B.; Browell, Edward V.
1988-01-01
Attenuation measurements of the solar radiation between 1.5 and 15 micron wavelengths were performed with the airborne (DC-8) JPL MARK 4 interferometer during the 1987 Antarctic Expedition. The opacities not only provide information about the abundance of stratospheric gases but also about the optical depths of polar stratospheric clouds (PSCs) at wavelengths of negligible gas absorption (windows). The optical depth of PSCs can be determined for each window once the background attenuation, due to air-molecules and aerosol has been filtered out with a simple extinction law. The ratio of optical thicknesses at different wavelengths reveals information about particle size and particle composition. Among the almost 700 measured spectra only a few PSC cases exist. PSC events are identified by sudden reductions in the spectrally integrated intensity value and are also verified with backscattering data from an upward directed lidar instrument, that was mounted on the DC-8. For the selected case on September 21st at 14.40 GMT, lidar data indicate an optically thin cloud at 18k and later an additional optically thick cloud at 15 km altitude. All results still suffer from: (1) often arbitrary definitions of a clear case, that often already may have contained PSC particles and (2) noise problems that restrict the calculations of optical depths to values larger than 0.001. Once these problems are handled, this instrument may become a valuable tool towards a better understanding of the role PSCs play in the Antarctic stratosphere.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-17
... like. For observation of the sample, embodiments provide a thin-membrane window etched in the center of... windows. This gap may be adjusted by employing spacers. Alternatively, the thickness of a film established... optimize resolution each window may have a thickness on the order of 50 nm and the gap may be on the order...
Sputtered carbon as a corrosion barrier for x-ray detector windows
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rowley, Joseph; Pei, Lei; Davis, Robert C., E-mail: davis@byu.edu
Sputtered amorphous carbon thin films were explored as corrosion resistant coatings on aluminum thin films to be incorporated into x-ray detector windows. The requirements for this application include high corrosion resistance, low intrinsic stress, high strains at failure, and high x-ray transmission. Low temperature sputtering was used because of its compatibility with the rest of the window fabrication process. Corrosion resistance was tested by exposure of carbon coated and uncoated Al thin films to humidity. Substrate curvature and bulge testing measurements were used to determine intrinsic stress and ultimate strain at failure. The composition and bonding of the carbon filmsmore » were further characterized by electron energy loss spectroscopy, Raman spectroscopy, and carbon, hydrogen, and nitrogen elemental analyses. Samples had low compressive stress (down to.08 GPa), a high strain at failure (3%), and a low fraction of sp{sup 3} carbon–carbon bonds (less than 5%). The high breaking strain and excellent x-ray transmission of these sputtered carbon films indicate that they will work well as corrosion barriers in this application.« less
HOT CELL BUILDING, TRA632, INTERIOR. DETAIL OF HOT CELL NO. ...
HOT CELL BUILDING, TRA-632, INTERIOR. DETAIL OF HOT CELL NO. 2 SHOWS MANIPULATION INSTRUMENTS AND SHIELDED OPERATING WINDOWS. PENETRATIONS FOR OPERATING INSTRUMENTS GO THROUGH SHIELDING ABOVE WINDOWS. CONDUIT FOR UTILITIES AND CONTROLS IS BEHIND METAL CABINET BELOW WINDOWS NEAR FLOOR. CAMERA FACES WEST. WARNING SIGN LIMITS FISSILE MATERIAL TO SPECIFIED NUMBER OF GRAMS OF URANIUM AND PLUTONIUM. INL NEGATIVE NO. HD46-28-2. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID
Designing communication and remote controlling of virtual instrument network system
NASA Astrophysics Data System (ADS)
Lei, Lin; Wang, Houjun; Zhou, Xue; Zhou, Wenjian
2005-01-01
In this paper, a virtual instrument network through the LAN and finally remote control of virtual instruments is realized based on virtual instrument and LabWindows/CVI software platform. The virtual instrument network system is made up of three subsystems. There are server subsystem, telnet client subsystem and local instrument control subsystem. This paper introduced virtual instrument network structure in detail based on LabWindows. Application procedure design of virtual instrument network communication, the Client/the programming mode of the server, remote PC and server communication far realizing, the control power of the workstation is transmitted, server program and so on essential technical were introduced. And virtual instruments network may connect to entire Internet on. Above-mentioned technology, through measuring the application in the electronic measurement virtual instrument network that is already built up, has verified the actual using value of the technology. Experiment and application validate that this design is resultful.
Studies on RF sputtered (WO3)1-x (V2O5)x thin films for smart window applications
NASA Astrophysics Data System (ADS)
Meenakshi, M.; Sivakumar, R.; Perumal, P.; Sanjeeviraja, C.
2016-05-01
V2O5 doped WO3 targets for RF sputtering thin film deposition were prepared for various compositions. Thin films of (WO3)1-x (V2O5)x were deposited on to glass substrates using these targets. Structural characteristics of the prepared targets and thin films were studied using X-ray diffraction. Laser Raman studies were carried out on the thin films to confirm the compound formation.
NASA Astrophysics Data System (ADS)
Anitha, M.; Saravanakumar, K.; Anitha, N.; Amalraj, L.
2018-06-01
Un-doped and co-doped (Zn + F) cadmium oxide (CdO) thin films were prepared by modified spray pyrolysis technique using a nebulizer on glass substrates kept at 200 °C. They were characterized by X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), scanning electron microscopy (SEM), UV-vis spectroscopy, Hall Effect and photoluminescence (PL) respectively. The thin films were having thickness in the range of 520-560 nm. They were well crystalline and displayed high transparency of about >70% in the visible region. It was clearly seen from the SEM photographs that co-doping causes notable changes in the surface morphology. Electrical study exhibited the resistivity of co-doped CdO thin films drastically fell to 1.43 × 10-4 Ω-cm compared with the un-doped CdO thin film. The obtained PL spectra were well corroborated with the structural and optical studies. The high transparency, wide band gap energy and enhanced electrical properties obtained infer that Zn + F co-doped CdO thin films find application in optoelectronic devices, especially in window layer of solar cells.
NASA Technical Reports Server (NTRS)
Lee, Yong-Keun; Yang, Ping; Hu, Yongxiang; Baum, Bryan A.; Loeb, Norman G.; Gao, Bo-Cai
2006-01-01
We investigate the outgoing broadband longwave (LW, 5 to approx. 200 microns) and window (WIN, 8 to approx. 12 microns) channel radiances at the top of atmosphere (TOA) under clear-sky conditions, using data acquired by the Cloud and the Earth s Radiant Energy System (CERES) and Moderate-Resolution Imaging Spectroradiometer (MODIS) instruments onboard the NASA Terra satellite platform. In this study, detailed analyses are performed on the CERES Single Scanner Footprint TOA/Surface Fluxes and Clouds product to understand the radiative effect of thin cirrus. The data are acquired over the Florida area during the Cirrus Regional Study of Tropical Anvils and Cirrus Layers Florida Area Cirrus Experiment (CRYSTAL-FACE) field program. Of particular interest is the anisotropy associated with the radiation field. Measured CERES broadband radiances are compared to those obtained from rigorous radiative transfer simulations. Analysis of results from this comparison indicates that the simulated radiances tend to be larger than their measured counterparts, with differences ranging from 2.1% to 8.3% for the LW band and from 1.7% to 10.6% for the WIN band. The averaged difference in radiance is approximately 4% for both the LW and WIN channels. A potential cause for the differences could be the presence of thin cirrus (i.e., optically thin ice clouds with visible optical thicknesses smaller than approximately 0.3). The detection and quantitative analysis of these thin cirrus clouds are challenging even with sophisticated multispectral instruments. While large differences in radiance between the CERES observations and the theoretical calculations are found, the corresponding difference in the anisotropic factors is very small (0.2%). Furthermore, sensitivity studies show that the influence due to a 1 K bias of the surface temperature on the errors of the LW and WIN channel radiances is of the same order as that associated with a 2% bias of the surface emissivity. The LW and WIN errors associated with a 5% bias of water vapor amount in the lower atmosphere in conjunction with a 50% bias of water vapor amount in the upper atmosphere is similar to that of a 1 K bias of the vertical temperature profile. Even with the uncertainties considered for these various factors, the simulated LW and WIN radiances are still larger than the observed radiances if thin cirrus clouds are excluded.
Wilhelm, William G.
1982-01-01
The field of this invention is solar collectors, and more particularly, the invention pertains to a flat plate collector that employs high performance thin films. The solar collector of this invention overcomes several problems in this field, such as excessive hardware, cost and reliability, and other prior art drawbacks outlined in the specification. In the preferred form, the apparatus features a substantially rigid planar frame (14). A thin film window (42) is bonded to one planar side of the frame. An absorber (24) of laminate construction is comprised of two thin film layers (24a, 24b) that are sealed perimetrically. The layers (24a, 24b) define a fluid-tight planar envelope (24c) of large surface area to volume through which a heat transfer fluid flows. Absorber (24) is bonded to the other planar side of the frame. The thin film construction of the absorber assures substantially full envelope wetting and thus good efficiency. The window and absorber films stress the frame adding to the overall strength of the collector.
The optical and electrochemical properties of electrochromic films: WO3+xV2O5
NASA Astrophysics Data System (ADS)
Li, Zhuying; Liu, Hui; Liu, Ye; Yang, Shaohong; Liu, Yan; Wang, Chong
2010-05-01
Since Deb's experiment in 1973 on the electrochromic effect, transmissive electrochromic films exhibit outstanding potential as energy efficient window controls which allow dynamic control of the solar energy transmission. These films with non-volatile memory, once in the coloured state, remain in the same state even after removal of the field. The optical and electrochemical properties of electrochromic films using magnetron sputter deposition tungsten oxide thin films and vanadium oxide doped tungsten-vanadium oxide thin films on ITO coated glass were investigated. From the UV region of the transmittance spectra, the optical band gap energy from the fundamental absorption edge can be determined. And the Cyclic voltammograms of these thin films in 1 mol LiClO4 propylene carbonate electrolyte (LIPC) were measured and analysed. The anode electrochromic V2O5 doped cathode electrochromic WO3 could make films colour changing while the transmittance of films keeped invariance. These performance characteristics make tungstenvanadium oxide colour changeably thin films are suitable for electrochromic windows applications.
Evaluation of beam tracking strategies for the THOR-CSW solar wind instrument
NASA Astrophysics Data System (ADS)
De Keyser, Johan; Lavraud, Benoit; Prech, Lubomir; Neefs, Eddy; Berkenbosch, Sophie; Beeckman, Bram; Maggiolo, Romain; Fedorov, Andrei; Baruah, Rituparna; Wong, King-Wah; Amoros, Carine; Mathon, Romain; Génot, Vincent
2017-04-01
We compare different beam tracking strategies for the Cold Solar Wind (CSW) plasma spectrometer on the ESA M4 THOR mission candidate. The goal is to intelligently select the energy and angular windows the instrument is sampling and to adapt these windows as the solar wind properties evolve, with the aim to maximize the velocity distribution acquisition rate while maintaining excellent energy and angular resolution. Using synthetic data constructed using high-cadence measurements by the Faraday cup instrument on the Spektr-R mission (30 ms resolution), we test the performance of energy beam tracking with or without angular beam tracking. The algorithm can be fed both by data acquired by the plasma spectrometer during the previous measurement cycle, or by data from another instrument, in casu the Faraday Cup (FAR) instrument foreseen on THOR. We verify how these beam tracking algorithms behave for different sizes of the energy and angular windows, and for different data integration times, in order to assess the limitations of the algorithm and to avoid situations in which the algorithm loses track of the beam.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meenakshi, M.; Perumal, P.; Sivakumar, R.
2016-05-23
V{sub 2}O{sub 5} doped WO{sub 3} targets for RF sputtering thin film deposition were prepared for various compositions. Thin films of (WO{sub 3}){sub 1-x} (V{sub 2}O{sub 5}){sub x} were deposited on to glass substrates using these targets. Structural characteristics of the prepared targets and thin films were studied using X-ray diffraction. Laser Raman studies were carried out on the thin films to confirm the compound formation.
Infrared characteristics of VO2 thin films for smart window and laser protection applications
NASA Astrophysics Data System (ADS)
Huang, Zhangli; Chen, Sihai; Lv, Chaohong; Huang, Ying; Lai, Jianjun
2012-11-01
Vanadium dioxide (VO2) films with a low semiconductor-to-metal transition temperature of 45 °C were fabricated through direct current magnetron sputtering followed by a post-annealing. Atomic force microscopy measurements show that the VO2 grain size is about one hundred of nanometers. Infrared (IR) characteristic is well investigated by applying a He-Ne laser power intensity measurement, and the result reveals that the VO2 film exhibits excellent IR switching property. Furthermore, solar smart window and laser protection experiments demonstrate that the obtained VO2 thin film is a promising material for the application in related fields.
Outgassing models for Landsat-4 thematic mapper short wave infrared bands
Micijevic, E.; Helder, D.L.; ,
2005-01-01
Detector responses to the Internal Calibrator (IC) pulses in the Landsat-4 Thematic Mapper (TM) have been observed to follow an oscillatory behavior. This phenomenon is present only in the Short Wave Infrared (SWIR) bands and has been observed throughout the lifetime of the instrument, which was launched in July 1982 and imaged the Earth's surface until late 1993. These periodic changes in amplitude, which can be as large as 7.5 percent, are known as outgassing effects and are believed to be due to optical interference caused by a gradual buildup of an ice-like material on the window of the cryogenically cooled dewar containing the SWIR detectors. Similar outgassing effects in the Landsat-5 TM have been characterized using an optical thin-film model that relates detector behavior to the ice film growth rate, which was found to gradually decrease with time. A similar approach, which takes into consideration the different operational history of the instrument, has been applied in this study to three closely sampled data sets acquired throughout the lifetime of the Landsat-4 TM. Although Landsat-4 and Landsat-5 Thematic Mappers are essentially identical instruments, data generated from analyses of outgassing effects indicate subtle, but important, differences between the two. The estimated lifetime model could improve radiometric accuracy by as much as five percent.
Superconductive hot-electron-bolometer mixer receiver for 800-GHz operation
NASA Astrophysics Data System (ADS)
Kawamura, J.; Blundell, R.; Tong, C.-Y. E.; Papa, D. C.; Hunter, T. R.; Paine, S. N.; Patt, F.; Gol'Tsman, G.; Cherednichenko, S.; Voronov, B.; Gershenzon, E.
2000-04-01
In this paper, we describe a superconductive hot-electron-bolometer mixer receiver designed to operate in the partially transmissive 350-μm atmospheric window. The receiver employs an NbN thin-film microbridge as the mixer element, in which the main cooling mechanism of the hot electrons is through electron-phonon interaction. At a local-oscillator frequency of 808 GHz, the measured double-sideband receiver noise temperature is Trx=970 K, across a 1-GHz intermediate-frequency bandwidth centered at 1.8 GHz. We have measured the linearity of the receiver and the amount of local-oscillator power incident on the mixer for optimal operation, which is PLO ≈ 1 microwatt. This receiver was used in making observations as a facility instrument at the Heinrich Hertz Telescope, Mt. Graham, AZ, during the 1998-1999 winter observing season.
Microcalorimeters for High Resolution X-Ray Spectroscopy of Laboratory and Astrophysical Plasmas
NASA Technical Reports Server (NTRS)
Silver, E.; Flowers, Bobby J. (Technical Monitor)
2003-01-01
The proposal has three major objectives. The first focuses on advanced neutron-transmutation-doped (NTD)-based microcalorimeter development. Our goal is to develop an array of microcalorimeters with sub- 5 eV energy resolution that can operate with pile-up-free throughput of at least 100 Hz per pixel. The second objective is to establish our microcalorimeter as an essential x-ray diagnostic for laboratory astrophysics studies. We propose to develop a dedicated microcalorimeter spectrometer for the EBIT (electron beam ion trap). This instrument will incorporate the latest detector and cryogenic technology that we have available. The third objective is to investigate innovative ideas related to possible flight opportunities. These include compact, long lived cryo-systems, ultra-low temperature cold stages, low mass and low power electronics, and novel assemblies of thin windows with high x-ray transmission.
Thin CVD-diamond RF Pill-Box vacuum windows for LHCD systems
NASA Astrophysics Data System (ADS)
Ravera, G. L.; Ceccuzzi, S.; Cardinali, A.; Cesario, R.; Mirizzi, F.; Schettini, G.; Tuccillo, A. A.
2014-02-01
The preliminary assessment of a Lower Hybrid Current Drive (LHCD) system for the DEMOnstration power plant (DEMO) is mainly focused on the R&D needs of the less conventional RF components of the Main Transmission Line (MTL) and of the launcher. 500 kW, CW klystrons will be used to deliver the RF power to independent Passive Active Multijunction (PAM) launcher modules at 5 GHz. This paper describes the criteria followed to investigate the optimum solution for the RF window used as vacuum barrier between the MTL and the launcher, an open issue in the LHCD system for ITER too. The best candidate, capable of withstanding a power level of, or above, 0.5 MW in CW operation and to satisfy the electrical and thermonuclear requirements, is a Pill-Box assembly, based on a thin single disk of CVD-diamond as dielectric, water cooled at the edge. A thickness of 3 mm, much shorter than half a wavelength of the TE°11 mode in the dielectric as in the conventional window (unfeasible and too expensive with CVD-diamond at these frequencies), is sufficient to limit the exerted stress at the edge under the fracture stress for a maximum pressure applied of 0.9 MPa. In this paper the simulation results of conventional and thin CVD-diamond vacuum windows are presented comparing S-parameters, losses and electric fields in both matching condition and with VSWR = 2, using WR284 and WR229 as input/output rectangular waveguide.
All 2D, high mobility, flexible, transparent thin film transistor
Das, Saptarshi; Sumant, Anirudha V.; Roelofs, Andreas
2017-01-17
A two-dimensional thin film transistor and a method for manufacturing a two-dimensional thin film transistor includes layering a semiconducting channel material on a substrate, providing a first electrode material on top of the semiconducting channel material, patterning a source metal electrode and a drain metal electrode at opposite ends of the semiconducting channel material from the first electrode material, opening a window between the source metal electrode and the drain metal electrode, removing the first electrode material from the window located above the semiconducting channel material providing a gate dielectric above the semiconducting channel material, and providing a top gate above the gate dielectric, the top gate formed from a second electrode material. The semiconducting channel material is made of tungsten diselenide, the first electrode material and the second electrode material are made of graphene, and the gate dielectric is made of hexagonal boron nitride.
Eom, Taewoo; Park, Jeong Eun; Park, Sang Yong; Park, Jeong Hoon; Bweupe, Jackson; Lim, Donggun
2018-09-01
Copper indium gallium selenide (CIGS) thin film solar cells have been regarded as a candidate for energy conversion devices owing to their high absorption coefficient, high temperature stability, and low cost. ZnO:Al thin film is commonly used in CIGS solar cells as a window layer. In this study, ZnO:Al films were deposited on glass under various post-heat temperature using RF sputtering to observe the characteristics of ZnO:Al films such as Hall mobility, carrier concentration, and resistivity; subsequently, the ZnO:Al films were applied to a CIGS solar cell as a window. CIGS solar cells fabricated with various ZnO:Al films were analyzed in order to investigate their influence. The test results showed that the improvement of ZnO:Al characteristics affects Jsc and Voc in the solar cell through reduced recombination and increase of optical property.
Graphite Composite Booms with Integral Hinges
NASA Technical Reports Server (NTRS)
Alexander, Wes; Carlos, Rene; Rossoni, Peter; Sturm, James
2006-01-01
A document discusses lightweight instrument booms under development for use aboard spacecraft. A boom of this type comprises a thin-walled graphite fiber/ matrix composite tube with an integral hinge that can be bent for stowage and later allowed to spring back to straighten the boom for deployment in outer space. The boom design takes advantage of both the stiffness of the composite in tubular geometry and the flexibility of thin sections of the composite. The hinge is formed by machining windows in the tube at diametrically opposite locations so that there remain two opposing cylindrical strips resembling measuring tapes. Essential to the design is a proprietary composite layup that renders the hinge tough yet flexible enough to be bendable as much as 90 in either of two opposite directions. When the boom is released for deployment, the torque exerted by the bent hinge suffices to overcome parasitic resistance from harnesses and other equipment, so that the two sections of the hinge snap to a straight, rigid condition in the same manner as that of measuring tapes. Issues addressed in development thus far include selection of materials, out-of-plane bending, edge cracking, and separation of plies.
Yoo, Gang Yeol; Jeong, Jae-Seung; Lee, Soyoung; Lee, Youngki; Yoon, Hee Chang; Chu, Van Ben; Park, Gi Soon; Hwang, Yun Jeong; Kim, Woong; Min, Byoung Koun; Do, Young Rag
2017-05-03
There are four prerequisites when applying all types of thin-film solar cells to power-generating window photovoltaics (PVs): high power-generation efficiency, longevity and high durability, semitransparency or partial-light transmittance, and colorful and aesthetic value. Solid-type thin-film Cu(In,Ga)S 2 (CIGS) or Cu(In,Ga)(S,Se) 2 (CIGSSe) PVs nearly meet the first two criteria, making them promising candidates for power-generating window applications if they can transmit light to some degree and generate color with good aesthetic value. In this study, the mechanical scribing process removes 10% of the window CIGSSe thin-film solar cell with vacant line patterns to provide a partial-light-transmitting CIGSSe PV module to meet the third requirement. The last concept of creating distinct colors could be met by the addition of reflectance colors of one-dimensional (1D) photonic crystal (PC) dichroic film on the black part of a partial-light-transmitting CIGSSe PV module. Beautiful violets and blues were created on the cover glass of a black CIGSSe PV module via the addition of 1D PC blue-mirror-yellow-pass dichroic film to improve the aesthetic value of the outside appearance. As a general result from the low external quantum efficiency (EQE) and absorption of CIGSSe PVs below a wavelength of 400 nm, the harvesting efficiency and short-circuit photocurrent of CIGSSe PVs were reduced by only ∼10% without reducing the open-circuit voltage (V OC ) because of the reduced overlap between the absorption spectrum of CIGSSe PV and the reflectance spectrum of the 1D PC blue-mirror-yellow-pass dichroic film. The combined technology of partial-vacancy-scribed CIGSSe PV modules and blue 1D PC dichroic film can provide a simple strategy to be applied to violet/blue power-generating window applications, as such a strategy can improve the transparency and aesthetic value without significantly sacrificing the harvesting efficiency of the CIGSSe PV modules.
Hermetic Glass-To-Metal Seal For Instrumentation Window
NASA Technical Reports Server (NTRS)
Hill, Arthur J.
1992-01-01
Proposed mounting scheme for optical element of instrumentation window in pressure vessel ensures truly hermetic seal while minimizing transmission of stress to optical element. Brazed metal seal superior to conventional gaskets of elastomer, carbon, asbestos, or other material compressed between optical element and wall of vessel. Concentric brazed joints in proposed seal bond metal ring to wall of vessel and to optical element. U-shaped cross section allows ring to flex under pressure.
Muon catalyzed fusion beam window mechanical strength testing and analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ware, A.G.; Zabriskie, J.M.
A thin aluminum window (0.127 mm (0.005-inch) thick x 146 mm (5 3/4-inch) diameter) of 2024-T6 alloy was modeled and analyzed using the ABAQUS non-linear finite element analysis code. A group of windows was fabricated, heat-treated and subsequently tested. Testing included both ultimate burst pressure and fatigue. Fatigue testing cycles involved ''oil-canning'' behavior representing vacuum purge and reversal to pressure. Test results are compared to predictions and the mode of failure is discussed. Operational requirements, based on the above analysis and correlational testing, for the actual beam windows are discussed. 1 ref., 3 figs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Quarrie, L., E-mail: Lindsay.Quarrie@l-3com.com, E-mail: lindsay.o.quarrie@gmail.com; Air Force Research Laboratory, AFRL/RDLC Laser CoE, 3550 Aberdeen Avenue SE, Kirtland AFB, NM 87117-5776
The lifetime of Diode-Pumped Alkali Lasers (DPALs) is limited by damage initiated by reaction of the glass envelope of its gain medium with rubidium vapor. Rubidium is absorbed into the glass and the rubidium cations diffuse through the glass structure, breaking bridging Si-O bonds. A damage-resistant thin film was developed enhancing high-optical transmission at natural rubidium resonance input and output laser beam wavelengths of 780 nm and 795 nm, while protecting the optical windows of the gain cell in a DPAL. The methodology developed here can be readily modified for simulation of expected transmission performance at input pump and outputmore » laser wavelengths using different combination of thin film materials in a DPAL. High coupling efficiency of the light through the gas cell was accomplished by matching the air-glass and glass-gas interfaces at the appropriate wavelengths using a dielectric stack of high and low index of refraction materials selected to work at the laser energies and protected from the alkali metal vapor in the gain cell. Thin films as oxides of aluminum, zirconium, tantalum, and silicon were selected allowing the creation of Fabry-Perot optical filters on the optical windows achieving close to 100% laser transmission in a solid optic combination of window and highly reflective mirror. This approach allows for the development of a new whole solid optic laser.« less
Dorand, R Dixon; Barkauskas, Deborah S; Evans, Teresa A; Petrosiute, Agne; Huang, Alex Y
2014-01-01
Fluorescent imaging coupled with high-resolution femtosecond pulsed infrared lasers allows for interrogation of cellular interactions deeper in living tissues than ever imagined. Intravital imaging of the central nervous system (CNS) has provided insights into neuronal development, synaptic transmission, and even immune interactions. In this review we will discuss the two most common intravital approaches for studying the cerebral cortex in the live mouse brain for pre-clinical studies, the thinned skull and cranial window techniques, and focus on the advantages and drawbacks of each approach. In addition, we will discuss the use of neuronal physiologic parameters as determinants of successful surgical and imaging preparation. PMID:25568834
Thin Film Physical Sensor Instrumentation Research and Development at NASA Glenn Research Center
NASA Technical Reports Server (NTRS)
Wrbanek, John D.; Fralick, Gustave C.
2006-01-01
A range of thin film sensor technology has been demonstrated enabling measurement of multiple parameters either individually or in sensor arrays including temperature, strain, heat flux, and flow. Multiple techniques exist for refractory thin film fabrication, fabrication and integration on complex surfaces and multilayered thin film insulation. Leveraging expertise in thin films and high temperature materials, investigations for the applications of thin film ceramic sensors has begun. The current challenges of instrumentation technology are to further develop systems packaging and component testing of specialized sensors, further develop instrumentation techniques on complex surfaces, improve sensor durability, and to address needs for extreme temperature applications. The technology research and development ongoing at NASA Glenn for applications to future launch vehicles, space vehicles, and ground systems is outlined.
7. DETAIL SHOWING BLAST SHIELDED WINDOWS, WEST SIDE. Edwards ...
7. DETAIL SHOWING BLAST SHIELDED WINDOWS, WEST SIDE. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Instrumentation & Control Building, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA
3. NORTH FRONT, BULLET GLASS OBSERVATION WINDOWS FACE SLED TRACK. ...
3. NORTH FRONT, BULLET GLASS OBSERVATION WINDOWS FACE SLED TRACK. - Edwards Air Force Base, South Base Sled Track, Instrumentation & Control Building, South of Sled Track, Station "50" area, Lancaster, Los Angeles County, CA
Window Observational Research Facility (WORF)
NASA Technical Reports Server (NTRS)
Pelfrey, Joseph; Sledd, Annette
2007-01-01
This viewgraph document concerns the Window Observational Research Facility (WORF) Rack, a unique facility designed for use with the US Lab Destiny Module window. WORF will provide valuable resources for Earth Science payloads along with serving the purpose of protecting the lab window. The facility can be used for remote sensing instrumentation test and validation in a shirt sleeve environment. WORF will also provide a training platform for crewmembers to do orbital observations of other planetary bodies. WORF payloads will be able to conduct terrestrial studies utilizing the data collected from utilizing WORF and the lab window.
Coordinated STEM/FIB/NanoSIMS Analyses of Presolar Silicates in Comet Dust and Primitive Meteorites
NASA Technical Reports Server (NTRS)
Keller, Lindsay; Nguyen, A.; Rahman, Z.; Messenger, S.
2012-01-01
Silicate grains were among the most abundant mineralogical building blocks of our Solar System. These grains were the detritus from earlier generations of stars that have been recycled in the early solar nebula. Rare sub-micrometer survivors of this processing have been identified in meteorites, micrometeorites and interplanetary dust particles (IDPs). These silicate grains are recognized as presolar in origin because of their extremely anomalous isotopic compositions that reflect nucleosynthetic processes in their stellar sources (evolved stars, novae and supernovae). We perform coordinated chemical, mineralogical and isotopic studies of these grains to determine their origins and histories. We examine the complex mineralogy and petrography of presolar silicates using imaging, diffraction and chemical data obtained from thin sections with the JSC JEOL 2500 field-emission STEM equipped with a Noran thin window energy dispersive x-ray (EDX) spectrometer and a Gatan Tridiem GIF. Quantitative element x-ray maps (spectrum images) are acquired by rastering a 4 nm incident probe whose dwell time is minimized to avoid beam damage and element diffusion during mapping. Successive image layers are acquired and combined in order to achieve approx 1% counting statistics for major elements. The IDP samples are prepared by ultramicrotomy of particles embedded in epoxy or elemental sulfur. After EDX mapping, the sections are subjected to C, N, and O isotopic imaging with the JSC NanoSIMS 50L ion microprobe. We prepare sections of some meteorite grains using the JSC FEI Quanta 3D focused ion beam (FIB) instrument. The specimen surface is protected from the FIB milling process by layers of electron beam-deposited C and Pt followed by an ion-deposited Pt layer. We also use the FIB to preferentially remove surrounding grains to reduce the background in subsequent NanoSIMS measurements. For mineralogical studies, we again employ the FIB instrument to deposit a protective cap over the grain of interest and then extract the grain and thin it to electron transparency for TEM analysis.
Scanning transmission x-ray microscope for materials science spectromicroscopy at the ALS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Warwick, T.; Seal, S.; Shin, H.
1997-04-01
The brightness of the Advanced Light Source will be exploited by several new instruments for materials science spectromicroscopy over the next year or so. The first of these to become operational is a scanning transmission x-ray microscope with which near edge x-ray absorption spectra (NEXAFS) can be measured on spatial features of sub-micron size. Here the authors describe the instrument as it is presently implemented, its capabilities, some studies made to date and the developments to come. The Scanning Transmission X-ray Microscope makes use of a zone plate lens to produce a small x-ray spot with which to perform absorptionmore » spectroscopy through thin samples. The x-ray beam from ALS undulator beamline 7.0 emerges into the microscope vessel through a silicon nitride vacuum window 160nm thick and 300{mu}m square. The vessel is filled with helium at atmospheric pressure. The zone plate lens is illuminated 1mm downstream from the vacuum window and forms an image in first order of a pinhole which is 3m upstream in the beamline. An order sorting aperture passes the first order converging light and blocks the unfocused zero order. The sample is at the focus a few mm downstream of the zone plate and mounted from a scanning piezo stage which rasters in x and y so that an image is formed, pixel by pixel, by an intensity detector behind the sample. Absorption spectra are measured point-by-point as the photon energy is scanned by rotating the diffraction grating in the monochromator and changing the undulator gap.« less
Development of an X-ray surface analyzer for planetary exploration
NASA Technical Reports Server (NTRS)
Clark, B. C.
1972-01-01
An ultraminiature X-ray fluorescence spectrometer was developed which can obtain data on element composition not provided by present spacecraft instrumentation. The apparatus employs two radioisotope sources (Fe-55 and Cd-109) which irradiate adjacent areas on a soil sample. Fluorescent X-rays emitted by the sample are detected by four thin-window proportional counters. Using pulse-height discrimination, the energy spectra are determined. Virtually all elements above sodium in the periodic table are detected if present at sufficient levels. Minimum detection limits range from 30 ppm to several percent, depending upon the element and the matrix. For most elements, they are below 0.5 percent. Accuracies likewise depend upon the matrix, but are generally better than plus or minus 0.5 percent for all elements of atomic number greater than 14. Elements below sodium are also detected, but as a single group.
NASA Astrophysics Data System (ADS)
McFarlane Holman, Karen L.; Latimer, Matthew J.; Yachandra, Vittal K.
2004-06-01
X-ray absorption spectroscopy (XAS) in the intermediate x-ray region (2-6 keV) for dilute biological samples has been limited because of detector/flux limitations and inadequate cryogenic instrumentation. We have designed and constructed a new tailpiece/sample chamber for a commercially available liquid helium cooled cryostat which overcomes difficulties related to low fluorescence signals by using thin window materials and incorporating an internal photodiode detector. With the apparatus, XAS data at the Cl, S, and Ca K edges have been collected on frozen solutions and biological samples at temperatures down to 60 K. A separate chamber has been incorporated for collecting room-temperature spectra of standard compounds (for energy calibration purposes) which prevents contamination of the cryostat chamber and allows the sample to remain undisturbed, both important concerns for studying dilute and radiation-sensitive samples.
Thin metal film and multilayers experiment (A0138-3)
NASA Technical Reports Server (NTRS)
Delaboudiniere, J. P.; Berset, J. M.
1984-01-01
The sources of degradation of in state of the art and newly developed components and testing the usefulness of the concept of storing experiment samples in dry nitrogen under launch and space vacuum conditions during reentry mission phase were investigated. Ultraviolet (UV) and extreme ultraviolet (EUV) experiments suffer degradations during space missions of even 1 month duration. It is suggested that the degradation is due to condensation of outgassing products, followed by solar induced polymerization, however, penetrating charged particles are also known to produce volume effects. Degradation may also start immediately after manufacturing of the component due to oxidation, moisture, or chemical corrosion by atmospheric constituents such as CO2 and SO2. When the filters are used as windows for gas absorption cells or gas filters, or when they define the instrumental bandwidth by themselves. The effects of mechanical degradation by thermal cycling and/or dust may cause a dramatic impact.
Heterodyne Spectroscopy in the Thermal Infrared Region: A Window on Physics and Chemistry
NASA Technical Reports Server (NTRS)
Kostiuk, Theodor
2004-01-01
The thermal infrared region contains molecular bands of many of the most important species in gaseous astronomical sources. True shapes and frequencies of emission and absorption spectral lines from these constituents of planetary and stellar atmospheres contain unique information on local temperature and abundance distribution, non-thermal effects, composition, local dynamics and winds. Heterodyne spectroscopy in the thermal infrared can remotely measure true line shapes in relatively cool and thin regions and enable the retrieval of detailed information about local physics and chemistry. The concept and techniques for heterodyne detection will be discussed including examples of thermal infrared photomixers and instrumentation used in studies of several astronomical sources. Use of heterodyne detection to study non-LTE phenomena, planetary aurora, minor planetary species and gas velocities (winds) will be discussed. A discussion of future technological developments and relation to space flight missions will be addressed.
Prism Window for Optical Alignment
NASA Technical Reports Server (NTRS)
Tang, Hong
2008-01-01
A prism window has been devised for use, with an autocollimator, in aligning optical components that are (1) required to be oriented parallel to each other and/or at a specified angle of incidence with respect to a common optical path and (2) mounted at different positions along the common optical path. The prism window can also be used to align a single optical component at a specified angle of incidence. Prism windows could be generally useful for orienting optical components in manufacture of optical instruments. "Prism window" denotes an application-specific unit comprising two beam-splitter windows that are bonded together at an angle chosen to obtain the specified angle of incidence.
Theoretical vibro-acoustic modeling of acoustic noise transmission through aircraft windows
NASA Astrophysics Data System (ADS)
Aloufi, Badr; Behdinan, Kamran; Zu, Jean
2016-06-01
In this paper, a fully vibro-acoustic model for sound transmission across a multi-pane aircraft window is developed. The proposed model is efficiently applied for a set of window models to perform extensive theoretical parametric studies. The studied window configurations generally simulate the passenger window designs of modern aircraft classes which have an exterior multi-Plexiglas pane, an interior single acrylic glass pane and a dimmable glass ("smart" glass), all separated by thin air cavities. The sound transmission loss (STL) characteristics of three different models, triple-, quadruple- and quintuple-paned windows identical in size and surface density, are analyzed for improving the acoustic insulation performances. Typical results describing the influence of several system parameters, such as the thicknesses, number and spacing of the window panes, on the transmission loss are then investigated. In addition, a comparison study is carried out to evaluate the acoustic reduction capability of each window model. The STL results show that the higher frequencies sound transmission loss performance can be improved by increasing the number of window panels, however, the low frequency performance is decreased, particularly at the mass-spring resonances.
A Low Noise NbTiN-Based 850 GHz SIS Receiver for the Caltech Submillimeter Observatory
NASA Technical Reports Server (NTRS)
Kooi, J. W.; Kawamura, J.; Chen, J.; Chattopadhyay, G.; Pardo, J. R.; Zmuidzinas, J.; Phillips, T. G.; Bumble, B.; Stern, J.; LeDuc, H. G.
2000-01-01
We have developed a niobium titanium nitride (NbTiN) based superconductor- insulator-superconductor (SIS) receiver to cover the 350 micron atmospheric window. This frequency band lies entirely above the energy gap of niobium (700 GHz), a commonly used SIS superconductor. The instrument uses an open structure twin-slot SIS mixer that consists of two Nb/AlN/NbTiN tunnel junctions, NbTiN thin-film microstrip tuning elements, and a NbTiN ground plane. The optical configuration is very similar to the 850 GHz waveguide receiver that was installed at the Caltech Submillimeter Observatory (CSO) in 1997. To minimize front-end loss, we employed reflecting optics and a cooled beamsplitter at 4 K. The instrument has an uncorrected receiver noise temperature of 205K DSB at 800 GHz and 410K DSB at 900 GHz. The degradation in receiver sensitivity with frequency is primarily due to an increase in the mixer conversion loss, which is attributed to the mismatch between the SIS junction and the twin-slot antenna impedance. The overall system performance has been confirmed through its use at the telescope to detect a wealth of new spectroscopic lines.
4. DETAIL SHOWING PERISCOPE AND SHIELDED WINDOWS ON EAST SIDE, ...
4. DETAIL SHOWING PERISCOPE AND SHIELDED WINDOWS ON EAST SIDE, NORTH PART. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Instrumentation & Control Building, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA
NASA Astrophysics Data System (ADS)
2014-11-01
The Special issue presents the papers for the INERA Workshop entitled "Transition Metal Oxides as Functional Layers in Smart windows and Water Splitting Devices", which was held in Varna, St. Konstantin and Elena, Bulgaria, from the 4th-6th September 2014. The Workshop is organized within the context of the INERA "Research and Innovation Capacity Strengthening of ISSP-BAS in Multifunctional Nanostructures", FP7 Project REGPOT 316309 program, European project of the Institute of Solid State Physics at the Bulgarian Academy of Sciences. There were 42 participants at the workshop, 16 from Sweden, Germany, Romania and Hungary, 11 invited lecturers, and 28 young participants. There were researchers present from prestigious European laboratories which are leaders in the field of transition metal oxide thin film technologies. The event contributed to training young researchers in innovative thin film technologies, as well as thin films characterization techniques. The topics of the Workshop cover the field of technology and investigation of thin oxide films as functional layers in "Smart windows" and "Water splitting" devices. The topics are related to the application of novel technologies for the preparation of transition metal oxide films and the modification of chromogenic properties towards the improvement of electrochromic and termochromic device parameters for possible industrial deployment. The Workshop addressed the following topics: Metal oxide films-functional layers in energy efficient devices; Photocatalysts and chemical sensing; Novel thin film technologies and applications; Methods of thin films characterizations; From the 37 abstracts sent, 21 manuscripts were written and later refereed. We appreciate the comments from all the referees, and we are grateful for their valuable contributions. Guest Editors: Assoc. Prof. Dr.Tatyana Ivanova Prof. DSc Kostadinka Gesheva Prof. DSc Hassan Chamatti Assoc. Prof. Dr. Georgi Popkirov Workshop Organizing Committee Prof.DSc Kostadinka Gesheva, Central Laboratory of Solar Energy and New Energy Sources, Bulgarian Academy of Sciences (CL SENES-BAS) - Chairperson Assoc. Prof. Dr Anna Szekeres - Institute of Solid State Physics- BAS Assoc. Prof Dr. Tatyana Ivanova - CL SENES -BAS Assist. Prof. Radostina Kamburova - ISSP-BAS
Electrochromic NiO thin films prepared by spin coating
NASA Astrophysics Data System (ADS)
Özütok, F.; Demiri, S.; Özbek, E.
2017-02-01
Recently, smart windows are very important because they are often being used in smart buildings and car glasses (windows). At this point, producing effective electrochromic materials is so necessary. In this study, we produced NiO thin films by using spin coating technique on In-doped SnO2 (ITO) substrate. Nickel proportions of these nickel oxide (NiO) films are 3, 5 and 7 %. Nickel acetate tetrahydrate is the initial solution and solvents are ethylene gl ycol and n-hexzane. Structural properties and surface images are investigated by using x-ray diffactometer (XRD) and scanning electron microscope (SEM) device, respectively. In addition, electrochemical behavior is investigated by cyclic voltammetry. A correlation between surface morphology and electrochromic performance was observed as well.
NASA Astrophysics Data System (ADS)
Minami, Tadatsugu; Nishi, Yuki; Miyata, Toshihiro
2016-05-01
Efficiency enhancement was achieved in Cu2O-based heterojunction solar cells fabricated with a zinc-germanium-oxide (Zn1- x Ge x -O) thin film as the n-type window layer and a p-type Na-doped Cu2O (Cu2O:Na) sheet prepared by thermally oxidizing Cu sheets. The Ge content (x) dependence of the obtained photovoltaic properties of the heterojunction solar cells is mainly explained by the conduction band discontinuity that results from the electron affinity difference between Zn1- x Ge x -O and Cu2O:Na. The optimal value of x in Zn1- x Ge x -O thin films prepared by pulsed laser deposition was observed to be 0.62. An efficiency of 8.1% was obtained in a MgF2/Al-doped ZnO/Zn0.38Ge0.62-O/Cu2O:Na heterojunction solar cell.
Optically detonated explosive device
NASA Technical Reports Server (NTRS)
Yang, L. C.; Menichelli, V. J. (Inventor)
1974-01-01
A technique and apparatus for optically detonating insensitive high explosives, is disclosed. An explosive device is formed by containing high explosive material in a house having a transparent window. A thin metallic film is provided on the interior surface of the window and maintained in contact with the high explosive. A laser pulse provided by a Q-switched laser is focussed on the window to vaporize the metallic film and thereby create a shock wave which detonates the high explosive. Explosive devices may be concurrently or sequentially detonated by employing a fiber optic bundle to transmit the laser pulse to each of the several individual explosive devices.
Window for radiation detectors and the like
Sparks, C.J. Jr.; Ogle, J.C.
1975-10-28
An improved x- and gamma-radiation and particle transparent window for the environment-controlling enclosure of various types of radiation and particle detectors is provided by a special graphite foil of a thickness of from about 0.1 to 1 mil. The graphite must have very parallel hexagonal planes with a mosaic spread no greater than 5$sup 0$ to have the necessary strength in thin sections to support one atmosphere or more of pressure. Such graphite is formed by hot- pressing and annealing pyrolytically deposited graphite and thereafter stripping off layers of sufficient thickness to form the window.
Noise reduction characteristics of general aviation type dual-pane windows
NASA Technical Reports Server (NTRS)
Grosveld, F.; Navaneethan, R.; Roskam, J.
1980-01-01
The noise reduction characteristics of general-aviation-type, dual-pane windows in various configurations have been experimentally investigated. The effects of inner and outer pane thickness, spacing between the panes, edge conditions, inclination of the inner pane and depressurization of the air in between the panes are presented. The space in between the two window panes is sealed airtight in all cases. Results show that increasing the mass of a 'floating' window pane does not increase the noise reduction below the fundamental resonance frequency. It is concluded that the concept of depressurization of the air between thin (1/8 in) Plexiglas panes and application of multiple-freedom edge conditions for the inner pane are promising to reduce noise levels in general aviation airplanes.
NASA Astrophysics Data System (ADS)
Hu, Shan
This research explores the application of carbon nanotube (CNT) films for active noise cancellation, solar energy harvesting and energy storage in building windows. The CNT-based components developed herein can be integrated into a solar-powered active noise control system for a building window. First, the use of a transparent acoustic transducer as both an invisible speaker for auxiliary audio playback and for active noise cancellation is accomplished in this work. Several challenges related to active noise cancellation in the window are addressed. These include secondary path estimation and directional cancellation of noise so as to preserve auxiliary audio and internal sounds while preventing transmission of external noise into the building. Solar energy can be harvested at a low rate of power over long durations while acoustic sound cancellation requires short durations of high power. A supercapacitor based energy storage system is therefore considered for the window. Using CNTs as electrode materials, two generations of flexible, thin, and fully solid-state supercapacitors are developed that can be integrated into the window frame. Both generations consist of carbon nanotube films coated on supporting substrates as electrodes and a solid-state polymer gel layer for the electrolyte. The first generation is a single-cell parallel-plate supercapacitor with a working voltage of 3 Volts. Its energy density is competitive with commercially available supercapacitors (which use liquid electrolyte). For many applications that will require higher working voltage, the second-generation multi-cell supercapacitor is developed. A six-cell device with a working voltage as high as 12 Volts is demonstrated here. Unlike the first generation's 3D structure, the second generation has a novel planar (2D) architecture, which makes it easy to integrate multiple cells into a thin and flexible supercapacitor. The multi-cell planar supercapacitor has energy density exceeding that of other planar supercapacitors in literature by more than one order of magnitude. All-solution fabrication processes were developed for both generations to achieve economical and scalable production. In addition to carbon nanotubes, nickel/nickel oxide core-shell nanowires were also studied as electrode materials for supercapacitors, for which high specific capacitance but low working voltage were obtained. Semi-transparent solar cells with carbon nanotube counter electrodes are developed to power the active noise cancellation system. They can be directly mounted on the glass panes and become part of the home window. The 2.67% efficiency achieved is higher than the 1.8% efficiency required for harvesting adequate energy to cancel noise of 70dB Day-Night-Level, which impacts on a north-facing window. In summary, this project develops several fundamental technologies that together can contribute to a solar-powered active noise cancellation system for a building window. At the same time, since the component technologies being developed are fundamental, it is also likely that they will have wider applications in other domains beyond building windows.
3. EAST SIDE FROM ATOP TUNNEL, SHOWING BLAST SHIELDED WINDOWS ...
3. EAST SIDE FROM ATOP TUNNEL, SHOWING BLAST SHIELDED WINDOWS AND PERISCOPE FACING TO TEST STAND 1-3. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Instrumentation & Control Building, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA
Ha, Tae-Jun; Cho, Won-Ju; Chung, Hong-Bay; Koo, Sang-Mo
2015-09-01
We investigate photo-induced instability in thin-film transistors (TFTs) consisting of amorphous indium-gallium-zinc-oxide (a-IGZO) as active semiconducting layers by comparing with hydrogenated amorphous silicon (a-Si:H). An a-IGZO TFT exhibits a large hysteresis window in the illuminated measuring condition but no hysteresis window in the dark condition. On the contrary, a large hysteresis window measured in the dark condition in a-Si:H was not observed in the illuminated condition. Even though such materials possess the structure of amorphous phase, optical responses or photo instability in TFTs looks different from each other. Photo-induced hysteresis results from initially trapped charges at the interface between semiconductor and dielectric films or in the gate dielectric which possess absorption energy to interact with deep trap-states and affect the movement of Fermi energy level. In order to support our claim, we also perform CV characteristics in photo-induced hysteresis and demonstrate thermal-activated hysteresis. We believe that this work can provide important information to understand different material systems for optical engineering which includes charge transport and band transition.
NASA Astrophysics Data System (ADS)
Sahu, Vikas Kumar; Das, Amit K.; Ajimsha, R. S.; Misra, P.
2018-05-01
The transient characteristics of resistive switching processes have been investigated in TiO2 thin films grown by atomic layer deposition (ALD) to study the temporal evolution of the switching processes and measure the switching times. The reset and set switching times of unipolar Au/TiO2/Pt devices were found to be ~250 µs and 180 ns, respectively in the voltage windows of 0.5–0.9 V for reset and 1.9–4.8 V for set switching processes, obtained from quasi-static measurements. The reset switching time decreased exponentially with increasing amplitude of applied reset voltage pulse, while the set switching time remained insensitive to the amplitude of the set voltage pulse. A fast reset process with a switching time of ~400 ns was achieved by applying a reset voltage of ~1.8 V, higher than that of the quasi-static reset voltage window but below the set voltage window. The sluggish reset process in TiO2 thin film and the dependence of the reset switching time on the amplitude of the applied voltage pulse was understood on the basis of a self-accelerated thermal dissolution model of conducting filaments (CFs), where a higher temperature of the CFs owing to enhanced Joule heating at a higher applied voltage imposes faster diffusion of oxygen vacancies, resulting in a shorter reset switching time. Our results clearly indicate that fast resistive switching with switching times in hundreds of nanoseconds can be achieved in ALD-grown TiO2 thin films. This may find applications in fast non-volatile unipolar resistive switching memories.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chang, C. L.; Carlstrom, J. E.; Datesman, A.
2008-04-01
The implementation of TES based microbolometer arrays will achieve unprecedented sensitivities for mm and sub-mm astronomy through fabrication of large format arrays and improved linearity and stability arising from strong electro-thermal feedback. We report on progress in developing TES microbolometers using Mo/Au thin films and Au absorbing structures. We present measurements of suppressing the thermal conductance through the etching of features on a continuous Silicon-Nitride window.
Superconductive radiofrequency window assembly
Phillips, Harry Lawrence; Elliott, Thomas S.
1998-01-01
The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The srf window assembly (20) has a superconducting metal-ceramic design. The srf window assembly (20) comprises a superconducting frame (30), a ceramic plate (40) having a superconducting metallized area, and a superconducting eyelet (50) for sealing plate (40) into frame (30). The plate (40) is brazed to eyelet (50) which is then electron beam welded to frame (30). A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the srf window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator.
Superconductive radiofrequency window assembly
Phillips, H.L.; Elliott, T.S.
1998-05-19
The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The SRF window assembly has a superconducting metal-ceramic design. The SRF window assembly comprises a superconducting frame, a ceramic plate having a superconducting metallized area, and a superconducting eyelet for sealing plate into frame. The plate is brazed to eyelet which is then electron beam welded to frame. A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the SRF window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator. 11 figs.
Superconducting radiofrequency window assembly
Phillips, Harry L.; Elliott, Thomas S.
1997-01-01
The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The srf window assembly (20) has a superconducting metal-ceramic design. The srf window assembly (20) comprises a superconducting frame (30), a ceramic plate (40) having a superconducting metallized area, and a superconducting eyelet (50) for sealing plate (40) into frame (30). The plate (40) is brazed to eyelet (50) which is then electron beam welded to frame (30). A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the srf window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator.
Superconducting radiofrequency window assembly
Phillips, H.L.; Elliott, T.S.
1997-03-11
The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The srf window assembly has a superconducting metal-ceramic design. The srf window assembly comprises a superconducting frame, a ceramic plate having a superconducting metallized area, and a superconducting eyelet for sealing plate into frame. The plate is brazed to eyelet which is then electron beam welded to frame. A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the srf window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator. 11 figs.
Development of a collapsible reinforced cylindrical space observation window
NASA Technical Reports Server (NTRS)
Khan, A. Q.
1971-01-01
Existing material technology was applied to the development of a collapsible transparent window suitable for manned spacecraft structures. The effort reported encompasses the evaluation of flame retardants intended for use in the window matrix polymer, evaluation of reinforcement angle which would allow for a twisting pantographing motion as the cylindrical window is mechanically collapsed upon itself, and evaluation of several reinforcement embedment methods. A fabrication technique was developed to produce a reinforced cylindrical space window of 45.7 cm diameter and 61.0 cm length. The basic technique involved the application of a clear film on a male-section mold; winding axial and girth reinforcements and vacuum casting the outer layer. The high-strength transparent window composite consisted of a polyether urethane matrix reinforced with an orthogonal pattern of black-coated carbon steel wire cable. A thin film of RTV silicone rubber was applied to both surfaces of the urethane. The flexibility, retraction system, and installation system are described.
Auvray, Roman; Ernoult, Augustin; Fabre, Benoît; Lagrée, Pierre-Yves
2014-07-01
This paper presents two models of sound production in flute-like instruments that allow time-domain simulations. The models are based on different descriptions of the jet flow within the window of the instrument. The jet-drive model depicts the jet by its transverse perturbation that interacts with the labium to produce sound. The discrete-vortex model depicts the jet as two independent shear layers along which vortices are convected and interact with the acoustic field within the window. The limit of validity between both models is usually discussed according to the aspect ratio of the jet W/h, with W the window length and h the flue channel height. The present simulations, compared with experimental data gathered on a recorder, allow to extend the aspect ratio criterion to the notion of dynamic aspect ratio defined as λ/h where λ is the hydrodynamic wavelength that now accounts for geometrical properties, such as W/h, as well as for dynamic properties, such as the Strouhal number. The two models are found to be applicable over neighboring values of geometry and blowing pressure.
NASA Astrophysics Data System (ADS)
Gambicorti, L.; Piazza, D.; Gerber, M.; Pommerol, A.; Roloff, V.; Ziethe, R.; Zimmermann, C.; Da Deppo, V.; Cremonese, G.; Ficai Veltroni, I.; Marinai, M.; Di Carmine, E.; Bauer, T.; Moebius, P.; Thomas, N.
2016-08-01
A new technique based on photolithographic processes of thin-film optical pass band coatings on a monolithic substrate has been applied to the filters of the Focal Plane Assembly (FPA) of the Colour and Stereo Surface Imaging System (CaSSIS) that will fly onboard of the ExoMars Trace Gas Orbiter to be launched in March 2016 by ESA. The FPA including is one of the spare components of the Simbio-Sys instrument of the Italian Space Agency (ASI) that will fly on ESA's Bepi Colombo mission to Mercury. The detector, developed by Raytheon Vision Systems, is a 2kx2k hybrid Si-PIN array with a 10 μm pixel. The detector is housed within a block and has filters deposited directly on the entrance window. The window is a 1 mm thick monolithic plate of fused silica. The Filter Strip Assembly (FSA) is produced by Optics Balzers Jena GmbH and integrated on the focal plane by Leonardo-Finmeccanica SpA (under TAS-I responsibility). It is based on dielectric multilayer interference coatings, 4 colour bands selected with average in-band transmission greater than 95 percent within wavelength range (400-1100 nm), giving multispectral images on the same detector and thus allows CaSSIS to operate in push-frame mode. The Field of View (FOV) of each colour band on the detector is surrounded by a mask of low reflective chromium (LRC), which also provides with the straylight suppression required (an out-of-band transmission of less than 10-5/nm). The mask has been shown to deal effectively with cross-talk from multiple reflections between the detector surface and the filter. This paper shows the manufacturing and optical properties of the FSA filters and the FPA preliminary on-ground calibration results.
Anisotropic vanadium dioxide sculptured thin films with superior thermochromic properties.
Sun, Yaoming; Xiao, Xiudi; Xu, Gang; Dong, Guoping; Chai, Guanqi; Zhang, Hua; Liu, Pengyi; Zhu, Hanmin; Zhan, Yongjun
2013-09-25
VO2 (M) STF through reduction of V2O5 STF was prepared. The results illustrate that V2O5 STF can be successfully obtained by oblique angle thermal evaporation technique. After annealing at 550 °C/3 min, the V2O5 STF deposited at 85° can be easily transformed into VO2 STF with slanted columnar structure and superior thermochromic properties. After deposition SiO2 antireflective layer, Tlum of VO2 STF is enhanced 26% and ΔTsol increases 60% compared with that of normal VO2 thin films. Due to the anisotropic microstructure of VO2 STF, angular selectivity transmission of VO2 STF is observed and the solar modulation ability is further improved from 7.2% to 8.7% when light is along columnar direction. Moreover, the phase transition temperature of VO2 STF can be depressed into 54.5 °C without doping. Considering the oblique incidence of sunlight on windows, VO2 STF is more beneficial for practical application as smart windows compared with normal homogenous VO2 thin films.
Anisotropic vanadium dioxide sculptured thin films with superior thermochromic properties
Sun, Yaoming; Xiao, Xiudi; Xu, Gang; Dong, Guoping; Chai, Guanqi; Zhang, Hua; Liu, Pengyi; Zhu, Hanmin; Zhan, Yongjun
2013-01-01
VO2 (M) STF through reduction of V2O5 STF was prepared. The results illustrate that V2O5 STF can be successfully obtained by oblique angle thermal evaporation technique. After annealing at 550°C/3 min, the V2O5 STF deposited at 85° can be easily transformed into VO2 STF with slanted columnar structure and superior thermochromic properties. After deposition SiO2 antireflective layer, Tlum of VO2 STF is enhanced 26% and ΔTsol increases 60% compared with that of normal VO2 thin films. Due to the anisotropic microstructure of VO2 STF, angular selectivity transmission of VO2 STF is observed and the solar modulation ability is further improved from 7.2% to 8.7% when light is along columnar direction. Moreover, the phase transition temperature of VO2 STF can be depressed into 54.5°C without doping. Considering the oblique incidence of sunlight on windows, VO2 STF is more beneficial for practical application as smart windows compared with normal homogenous VO2 thin films. PMID:24067743
Planck 2015 results. IV. Low Frequency Instrument beams and window functions
NASA Astrophysics Data System (ADS)
Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartolo, N.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bock, J. J.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Bucher, M.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cardoso, J.-F.; Catalano, A.; Chamballu, A.; Christensen, P. R.; Colombi, S.; Colombo, L. P. L.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Dickinson, C.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Ducout, A.; Dupac, X.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Fergusson, J.; Finelli, F.; Forni, O.; Frailis, M.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Giard, M.; Giraud-Héraud, Y.; Gjerløw, E.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Hansen, F. K.; Hanson, D.; Harrison, D. L.; Henrot-Versillé, S.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hovest, W.; Huffenberger, K. M.; Hurier, G.; Jaffe, A. H.; Jaffe, T. R.; Juvela, M.; Keihänen, E.; Keskitalo, R.; Kiiveri, K.; Kisner, T. S.; Knoche, J.; Kunz, M.; Kurki-Suonio, H.; Lähteenmäki, A.; Lamarre, J.-M.; Lasenby, A.; Lattanzi, M.; Lawrence, C. R.; Leahy, J. P.; Leonardi, R.; Lesgourgues, J.; Levrier, F.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; Lindholm, V.; López-Caniego, M.; Lubin, P. M.; Macías-Pérez, J. F.; Maggio, G.; Maino, D.; Mandolesi, N.; Mangilli, A.; Maris, M.; Martin, P. G.; Martínez-González, E.; Masi, S.; Matarrese, S.; Mazzotta, P.; McGehee, P.; Meinhold, P. R.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Montier, L.; Morgante, G.; Mortlock, D.; Moss, A.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; Novikov, D.; Novikov, I.; Paci, F.; Pagano, L.; Paoletti, D.; Partridge, B.; Pasian, F.; Patanchon, G.; Pearson, T. J.; Perdereau, O.; Perotto, L.; Perrotta, F.; Pettorino, V.; Piacentini, F.; Pierpaoli, E.; Pietrobon, D.; Pointecouteau, E.; Polenta, G.; Pratt, G. W.; Prézeau, G.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renzi, A.; Rocha, G.; Rosset, C.; Rossetti, M.; Roudier, G.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Savelainen, M.; Scott, D.; Seiffert, M. D.; Shellard, E. P. S.; Spencer, L. D.; Stolyarov, V.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Umana, G.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vassallo, T.; Vielva, P.; Villa, F.; Wade, L. A.; Wandelt, B. D.; Watson, R.; Wehus, I. K.; Yvon, D.; Zacchei, A.; Zonca, A.
2016-09-01
This paper presents the characterization of the in-flight beams, the beam window functions, and the associated uncertainties for the Planck Low Frequency Instrument (LFI). The structure of the paper is similar to that presented in the 2013 Planck release; the main differences concern the beam normalization and the delivery of the window functions to be used for polarization analysis. The in-flight assessment of the LFI main beams relies on measurements performed during observations of Jupiter. By stacking data from seven Jupiter transits, the main beam profiles are measured down to -25 dB at 30 and 44 GHz, and down to -30 dB at 70 GHz. It has been confirmed that the agreement between the simulated beams and the measured beams is better than 1% at each LFI frequency band (within the 20 dB contour from the peak, the rms values are 0.1% at 30 and 70 GHz; 0.2% at 44 GHz). Simulated polarized beams are used for the computation of the effective beam window functions. The error budget for the window functions is estimated from both main beam and sidelobe contributions, and accounts for the radiometer band shapes. The total uncertainties in the effective beam window functions are 0.7% and 1% at 30 and 44 GHz, respectively (at ℓ ≈ 600); and 0.5% at 70 GHz (at ℓ ≈ 1000).
Planck 2015 results: IV. Low Frequency Instrument beams and window functions
Ade, P. A. R.; Aghanim, N.; Ashdown, M.; ...
2016-09-20
This article presents the characterization of the in-flight beams, the beam window functions, and the associated uncertainties for the Planck Low Frequency Instrument (LFI). The structure of the paper is similar to that presented in the 2013 Planck release; the main differences concern the beam normalization and the delivery of the window functions to be used for polarization analysis. The in-flight assessment of the LFI main beams relies on measurements performed during observations of Jupiter. By stacking data from seven Jupiter transits, the main beam profiles are measured down to -25 dB at 30 and 44 GHz, and down tomore » -30 dB at 70 GHz. It has been confirmed that the agreement between the simulated beams and the measured beams is better than 1% at each LFI frequency band (within the 20 dB contour from the peak, the rms values are 0.1% at 30 and 70 GHz; 0.2% at 44 GHz). Simulated polarized beams are used for the computation of the effective beam window functions. The error budget for the window functions is estimated from both main beam and sidelobe contributions, and accounts for the radiometer band shapes. The total uncertainties in the effective beam window functions are 0.7% and 1% at 30 and 44 GHz, respectively (at ℓ ≈ 600); and 0.5% at 70 GHz (at ℓ ≈ 1000).« less
International Conference on Electromagnetic Windows (4th).
1981-08-15
ftJ S. TYPE OF REPORT & PERIOD COVER9D(j RINTERNATONAL CONFERENCE ON Conference -ELECTROMAGNETIC WINDOWS •s. -RPORtNG ORG. RDTMUA - C-5-81 7. AUTHOR(s...matching. About 20% bandwidth was claimed. It should be remembered that this technique is polarization sensitive and lacks the type of circular...various radome design options, for example, thin, half-wave solid,sandwich, and metal insert types , and followed this -3- C-5-81 by a discussion of
Experiments On Transparent Conductive Films For Spacecraft
NASA Technical Reports Server (NTRS)
Perez-Davis, Marla E.; Rutledge, Sharon K.; De Groh, Kim K.; Hung, Ching-Cheh; Malave-Sanabria, Tania; Hambourger, Paul; Roig, David
1995-01-01
Report describes experiments on thin, transparent, electrically conductive films made, variously, of indium tin oxide covered by magnesium fluoride (ITO/MgF2), aluminum-doped zinc oxide (AZO), or pure zinc oxide (ZnO). Films are candidates for application to such spacecraft components, including various optoelectronic devices and window surfaces that must be protected against buildup of static electric charge. On Earth, such films useful on heat mirrors, optoelectronic devices, gas sensors, and automotive and aircraft windows.
NASA Astrophysics Data System (ADS)
Yuce, H.; Alaboz, H.; Demirhan, Y.; Ozdemir, M.; Ozyuzer, L.; Aygun, G.
2017-11-01
Vanadium dioxide (VO2) shows metal-insulator phase transition at nearly 68 °C. This metal-insulator transition (MIT) in VO2 leads to a significant change in near-infrared transmittance and an abrupt change in the resistivity of VO2. Due to these characteristics, VO2 plays an important role on optic and electronic devices, such as thermochromic windows, meta-materials with tunable frequency, uncooled bolometers and switching devices. In this work, VO2 thin films were fabricated by reactive direct current magnetron sputtering in O2/Ar atmosphere on sapphire substrates without any further post annealing processes. The effect of sputtering parameters on optical characteristics and structural properties of grown thin films was investigated by SEM, XRD, Raman and UV/VIS spectrophotometer measurements. Patterning process of VO2 thin films was realized by e-beam lithography technique to monitor the temperature dependent electrical characterization. Electrical properties of VO2 samples were characterized using microprobe station in a vacuum system. MIT with hysteresis behavior was observed for the unpatterned square samples at around 68 °C. By four orders of magnitude of resistivity change was measured for the deposited VO2 thin films at transition temperature. After e-beam lithography process, substantial results in patterned VO2 thin films were observed. In this stage, for patterned VO2 thin films as stripes, the change in resistivity of VO2 was reduced by a factor of 10. As a consequence of electrical resistivity measurements, MIT temperature was shifted from 68 °C to 50 °C. The influence of e-beam process on the properties of VO2 thin films and the mechanism of the effects are discussed. The presented results contribute to the achievement of VO2 based thermochromic windows and bolometer applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wei, X.; Gu, W.; Chen, W.
2012-01-01
We investigated thin film morphologies of binary blends of alkyne-functionalized diblock copolymer poly(ethylene oxide)-block-poly(n-butyl methacrylate-random-propargyl methacrylate) (PEO-b-P(nBMA-r-PgMA)) and Rhodamine B azide, where the thermal alkyne/azide click reaction between the two components induced a disorder-to-order transition (DOT) of the copolymer. By controlling the composition of the neat copolymers and the mole ratio between the alkyne and azide groups, different microphase separated morphologies were achieved. At higher azide loading ratios, a perpendicular orientation of the microdomains was observed with wide accessible film thickness window. As less azide was incorporated, the microdomains have a stronger tendency to be parallel to the substrate, andmore » the film thickness window for perpendicular orientation also became narrower.« less
Modified hyperbolic sine model for titanium dioxide-based memristive thin films
NASA Astrophysics Data System (ADS)
Abu Bakar, Raudah; Syahirah Kamarozaman, Nur; Fazlida Hanim Abdullah, Wan; Herman, Sukreen Hana
2018-03-01
Since the emergence of memristor as the newest fundamental circuit elements, studies on memristor modeling have been evolved. To date, the developed models were based on the linear model, linear ionic drift model using different window functions, tunnelling barrier model and hyperbolic-sine function based model. Although using hyperbolic-sine function model could predict the memristor electrical properties, the model was not well fitted to the experimental data. In order to improve the performance of the hyperbolic-sine function model, the state variable equation was modified. On the one hand, the addition of window function cannot provide an improved fitting. By multiplying the Yakopcic’s state variable model to Chang’s model on the other hand resulted in the closer agreement with the TiO2 thin film experimental data. The percentage error was approximately 2.15%.
Cu-doped CdS and its application in CdTe thin film solar cell
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deng, Yi; College of Electronic and Information Engineering, Hankou University, Wuhan, Hubei 430212; Yang, Jun
2016-01-15
Cu is widely used in the back contact formation of CdTe thin film solar cells. However, Cu is easily to diffuse from the back contact into the CdTe absorber layer and even to the cell junction interface CdS/CdTe. This phenomenon is generally believed to be the main factor affecting the CdTe solar cell stability. In this study Cu was intentionally doped in CdS thin film to study its effect on the microstructural, optical and electrical properties of the CdS material. Upon Cu doping, the V{sub Cd{sup −}} and the surface-state-related photoluminescence emissions were dramatically decreased/quenched. The presence of Cu atommore » hindered the recrystallization/coalescence of the nano-sized grains in the as-deposited CdS film during the air and the CdCl{sub 2} annealing. CdTe thin film solar cell fabricated with Cu-doped CdS window layers demonstrated much decreased fill factor, which was induced by the increased space-charge recombination near the p-n junction and the worsened junction crystalline quality. Temperature dependent current-voltage curve measurement indicated that the doped Cu in the CdS window layer was not stable at both room and higher temperatures.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Aiping; Zhou, Honghui; Zhu, Yuanyuan
2016-11-10
Growth of unexpected phases from a composite target of BiFeO 3:BiMnO 3 and/or BiFeO 3:BiCrO 3 has been explored using pulsed laser deposition. The Bi 2FeMnO 6 tetragonal phase can be grown directly on SrTiO 3 (STO) substrate, while two phases (S1 and S2) were found to grow on LaAlO 3 (LAO) substrates with narrow growth windows. However, introducing a thin CeO 2 buffer layer effectively broadens the growth window for the pure S1 phase, regardless of the substrate. Moreover, we discovered two new phases (X1 and X2) when growing on STO substrates using a BiFeO 3:BiCrO 3 target. Puremore » X2 phase can be obtained on CeO 2-buffered STO and LAO substrates. This work demonstrates that some unexpected phases can be stabilized in a thin film form by using composite perovskite BiRO 3 (R = Cr, Mn, Fe, Co, Ni) targets. Moreover, it also indicates that CeO 2 can serve as a general template for the growth of bismuth compounds with potential room-temperature multiferroicity.« less
High-temperature, high-pressure optical port for rocket engine applications
NASA Technical Reports Server (NTRS)
Delcher, Ray; Nemeth, ED; Powers, W. T.
1993-01-01
This paper discusses the design, fabrication, and test of a window assembly for instrumentation of liquid-fueled rocket engine hot gas systems. The window was designed to allow optical measurements of hot gas in the SSME fuel preburner and appears to be the first window designed for application in a rocket engine hot gas system. Such a window could allow the use of a number of remote optical measurement technologies including: Raman temperature and species concentration measurement, Raleigh temperature measurements, flame emission monitoring, flow mapping, laser-induced florescence, and hardware imaging during engine operation. The window assembly has been successfully tested to 8,000 psi at 1000 F and over 11,000 psi at room temperature. A computer stress analysis shows the window will withstand high temperature and cryogenic thermal shock.
VizieR Online Data Catalog: XMM-Newton FOV brightest serendipitous sources (Marelli+, 2016)
NASA Astrophysics Data System (ADS)
Marelli, M.; Pizzocaro, D.; de, Luca A.; Gastaldello, F.; Caraveo, P.; Parkinson, P. S.
2018-02-01
Our deep XMM-Newton observation of PSR J2055+2539, lasting 136.2 ks, was performed on 2013 May 1 (ObsID 0724090101). The PN camera (Struder et al. 2001AJ....121.1413P) of the EPIC instrument was operating in Large Window mode, with a time resolution of 47.7 ms on a 27'x13' field of view (FOV). The high time resolution, combined with the large FOV, allows for both the timing analysis of the J2055 pulsar and the spatial analysis of the nebular structures. The Metal Oxide Semiconductor (MOS) detectors (Turner et al. 2001A&A...365L..27T) were set in full-frame mode (2.6 s time resolution on a 15' radius FOV). The thin optical filter was used for both PN and MOSs. We also analyzed XMM-Newton observations 0605470401 and 0605470901, taken on 2009 October 26 and on 2010 April 21, and lasting 24.5 and 17.9 ks, respectively. (1 data file).
Measurement of thin liquid film drainage using a novel high-speed impedance analyzer
NASA Astrophysics Data System (ADS)
Hool, Kevin O.; Saunders, Robert C.; Ploehn, Harry J.
1998-09-01
This work describes the design and implementation of a new instrument, called the thin film impedance analyzer, which measures the rate of drainage of thin oil films. The instrument forms an oil film by elevating a planar oil-water interface into a water drop hanging from a stainless steel capillary tube immersed in the oil. The instrument measures the magnitude of the impedance of the matter between the capillary tube and a screen electrode immersed in the lower water phase. Under appropriate conditions, the capacitance of the oil film dominates the impedance. The instrument records the increase in the magnitude of the admittance associated with the draining and thinning of the oil film. The features of the drainage curves vary considerably with the type, amount, and location of surfactants in the oil and water phases, as well as with user-specified values of drop volume, drop equilibration time, and extent of drop compression. For this reason, the instrument has utility as a screening tool for selecting surfactants for emulsion formulations. Potential future uses include accelerated prediction of emulsion stability and extraction of oil-water interfacial rheological parameters.
75 FR 29974 - Application(s) for Duty-Free Entry of Scientific Instruments
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-28
... portions of vertebrate and invertebrate organisms embedded in plastic resins and cut into thin sections... vertebrate and invertebrate organisms embedded in plastic resins and cut into thin sections mounted on... Use: The instrument will be used to examine portions of vertebrate and invertebrate organisms embedded...
NASA Technical Reports Server (NTRS)
Achilles, C. N.; Ming, Douglas W.; Morris, R. V.; Blake, D. F.
2012-01-01
The CheMin instrument on the Mars Science Laboratory (MSL) rover Curiosity is an X-ray diffraction (XRD) and X-ray fluorescence (XRF) instrument capable of providing the mineralogical and chemical compositions of rocks and soils on the surface of Mars. CheMin uses a microfocus X-ray tube with a Co target, transmission geometry, and an energy-discriminating X-ray sensitive CCD to produce simultaneous 2-D XRD patterns and energy-dispersive X-ray histograms from powdered samples. CheMin has two different window materials used for sample cells -- Mylar and Kapton. Instrument details are provided elsewhere. Fe/Mg-smectite (e.g., nontronite) has been identified in Gale Crater, the MSL future landing site, by CRISM spectra. While large quantities of phyllosilicate minerals will be easily detected by CheMin, it is important to establish detection limits of such phases to understand capabilities and limitations of the instrument. A previous study indicated that the (001) peak of smectite at 15 Ang was detectable in a mixture of 1 wt.% smectite with olivine when Mylar is the window material for the sample cell. Complications arise when Kapton is the window material because Kapton itself also has a diffraction peak near 15 Ang (6.8 deg 2 Theta). This study presents results of mineral mixtures of smectite and olivine to determine smectite detection limits for Kapton sample cells. Because the intensity and position of the smectite (001) peak depends on the hydration state, we also analyzed mixtures with "hydrated" and "dehydrated"h smectite to examine the effects of hydration state on detection limits.
Heterojunction solar cell with passivated emitter surface
Olson, Jerry M.; Kurtz, Sarah R.
1994-01-01
A high-efficiency heterojunction solar cell wherein a thin emitter layer (preferably Ga.sub.0.52 In.sub.0.48 P) forms a heterojunction with a GaAs absorber layer. A passivating window layer of defined composition is disposed over the emitter layer. The conversion efficiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the window layer.
Heterojunction solar cell with passivated emitter surface
Olson, J.M.; Kurtz, S.R.
1994-05-31
A high-efficiency heterojunction solar cell is described wherein a thin emitter layer (preferably Ga[sub 0.52]In[sub 0.48]P) forms a heterojunction with a GaAs absorber layer. A passivating window layer of defined composition is disposed over the emitter layer. The conversion efficiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the window layer. 1 fig.
Replacement Sequence of Events Generator
NASA Technical Reports Server (NTRS)
Fisher, Forest; Gladden, Daniel Wenkert Roy; Khanampompan, Teerpat
2008-01-01
The soeWINDOW program automates the generation of an ITAR (International Traffic in Arms Regulations)-compliant sub-RSOE (Replacement Sequence of Events) by extracting a specified temporal window from an RSOE while maintaining page header information. RSOEs contain a significant amount of information that is not ITAR-compliant, yet that foreign partners need to see for command details to their instrument, as well as the surrounding commands that provide context for validation. soeWINDOW can serve as an example of how command support products can be made ITAR-compliant for future missions. This software is a Perl script intended for use in the mission operations UNIX environment. It is designed for use to support the MRO (Mars Reconnaissance Orbiter) instrument team. The tool also provides automated DOM (Distributed Object Manager) storage into the special ITAR-okay DOM collection, and can be used for creating focused RSOEs for product review by any of the MRO teams.
Global-scale surface spectral variations on Titan seen from Cassini/VIMS
Barnes, J.W.; Brown, R.H.; Soderblom, L.; Buratti, B.J.; Sotin, Christophe; Rodriguez, S.; Le, Mouelic S.; Baines, K.H.; Clark, R.; Nicholson, P.
2007-01-01
We present global-scale maps of Titan from the Visual and Infrared Mapping Spectrometer (VIMS) instrument on Cassini. We map at 64 near-infrared wavelengths simultaneously, covering the atmospheric windows at 0.94, 1.08, 1.28, 1.6, 2.0, 2.8, and 5 ??m with a typical resolution of 50 km/pixel or a typical total integration time of 1 s. Our maps have five to ten times the resolution of ground-based maps, better spectral resolution across most windows, coverage in multiple atmospheric windows, and represent the first spatially resolved maps of Titan at 5 ??m. The VIMS maps provide context and surface spectral information in support of other Cassini instruments. We note a strong latitudinal dependence in the spectral character of Titan's surface, and partition the surface into 9 spectral units that we describe in terms of spectral and spatial characteristics. ?? 2006 Elsevier Inc. All rights reserved.
Single-crystalline BaTiO3 films grown by gas-source molecular beam epitaxy
NASA Astrophysics Data System (ADS)
Matsubara, Yuya; Takahashi, Kei S.; Tokura, Yoshinori; Kawasaki, Masashi
2014-12-01
Thin BaTiO3 films were grown on GdScO3 (110) substrates by metalorganic gas-source molecular beam epitaxy. Titanium tetra-isopropoxide (TTIP) was used as a volatile precursor that provides a wide growth window of the supplied TTIP/Ba ratio for automatic adjustment of the film composition. Within the growth window, compressively strained films can be grown with excellent crystalline quality, whereas films grown outside of the growth window are relaxed with inferior crystallinity. This growth method will provide a way to study the intrinsic properties of ferroelectric BaTiO3 films and their heterostructures by precise control of the stoichiometry, structure, and purity.
Horizontal film balance having wide range and high sensitivity
Abraham, B.M.; Miyano, K.; Ketterson, J.B.
1981-03-05
A thin-film, horizontal balance instrument is provided for measuring surface tension (surface energy) of thin films suspended on a liquid substrate. The balance includes a support bearing and an optical feedback arrangement for wide-range, high sensitivity measurements. The force on the instrument is balanced by an electromagnet, the current through the magnet providing a measure of the force applied to the instrument. A novel float construction is also disclosed.
Horizontal film balance having wide range and high sensitivity
Abraham, B.M.; Miyano, K.; Ketterson, J.B.
1983-11-08
A thin-film, horizontal balance instrument is provided for measuring surface tension (surface energy) of thin films suspended on a liquid substrate. The balance includes a support bearing and an optical feedback arrangement for wide-range, high sensitivity measurements. The force on the instrument is balanced by an electromagnet, the current through the magnet providing a measure of the force applied to the instrument. A novel float construction is also disclosed. 5 figs.
Horizontal film balance having wide range and high sensitivity
Abraham, Bernard M.; Miyano, Kenjiro; Ketterson, John B.
1983-01-01
A thin-film, horizontal balance instrument is provided for measuring surface tension (surface energy) of thin films suspended on a liquid substrate. The balance includes a support bearing and an optical feedback arrangement for wide-range, high sensitivity measurements. The force on the instrument is balanced by an electromagnet, the current through the magnet providing a measure of the force applied to the instrument. A novel float construction is also disclosed.
Geminiani, Alessandro; Weitz, Daniel S; Ercoli, Carlo; Feng, Changyong; Caton, Jack G; Papadimitriou, Dimitrios E V
2015-04-01
Sonic instruments may reduce perforation rates of the schneiderian membrane during lateral window sinus augmentation procedures. This study compares the incidence of membrane perforations using a sonic handpiece with an oscillating diamond insert versus a turbine handpiece with a conventional rotary diamond stone during lateral window sinus augmentation procedures. A retrospective chart analysis identified all lateral window sinus augmentation procedures done during a defined period. Among these procedures, those performed with a sonic handpiece and an oscillating diamond insert (experimental) and those performed with a conventional turbine and rotary diamond stone (conventional) were selected for this study. Reported occurrences of sinus membrane perforations during preparation of the osteotomy and elevation of the sinus membrane, as well as postoperative complications, were recorded and compared between treatment groups. Ninety-three consecutive patients were identified for a total of 130 sinus augmentation procedures (51 conventional, 79 experimental). Schneiderian membrane perforations were noted during preparation of the lateral window osteotomy in 27.5% of the sinuses in the conventional group and 12.7% of sinuses in the experimental group. During membrane elevation, perforations were noted in 43.1% of the sinuses in the conventional group and 25.3% of sinuses in the experimental group. Both differences in perforation rates were statistically significant (p < .05). There was no statistically significant difference in postoperative complications. In this study, the use of a sonic instrument to prepare the lateral window osteotomy during sinus elevation procedures resulted in a reduced perforation rate of the Schneiderian membrane compared with the conventional turbine instrument. © 2013 Wiley Periodicals, Inc.
Fabrication of MgF2 and LiF windows for the Hubble Space Telescope Imaging Spectrograph
NASA Technical Reports Server (NTRS)
Gormley, Daphne; Bottema, Murk; Darnell, Barbara; Fowler, Walter; Medenica, Walter
1988-01-01
Two prototype test windows (MgF2 and LiF) to be used on the 75-mm UV MAMA detector tubes for the Hubble Space Telescope Imaging Spectrograph are described. The spatial and optical constraints of this instrument dictate that the thickness of the window materials be no greater than 2-3 mm to achieve a minimum 50-percent transmission at hydrogen Lyman alpha (121.6 nm), and that the window must be domed to minimize optical aberrations and provide structural strength. The detector window has an input diameter of about 100 mm with a radius-of-curvature of 70 mm. The manufacturing processes involved in the fabrication of these windows is discussed, as well as test programs (optical and structural) to be performed at Goddard Space Flight Center.
Did the Eruption of the Mt. Pinatubo Volcano Affect Cirrus Properties?
NASA Technical Reports Server (NTRS)
Luo, Zhengzhao; Rossow, William B.; Inoue, Toshiro; Stubenrauch, Claudia J.; Hansen, James E. (Technical Monitor)
2001-01-01
Some observations suggest that the volcanic aerosols produced by the Mt. Pinatubo eruption may have altered cirrus properties. We look for evidence that such modification of cirrus is extensive enough to be climatically significant by comparing three satellite-based cirrus datasets produced by the ISCCP (International Satellite Cloud Climatology Project) analysis, the 'split-window' analysis, and 3I analysis. Since the former two have not been compared in detail before, we conduct such a comparison here. When applied to AVHRR (Advanced Very High Resolution Radiometer) data, both the ISCCP and split-window analyses identify about 0.2 - 0.3 cirrus cloud amount in tropical latitudes; however, there are detailed differences of classification for about half of these clouds. The discrepancies are attributed to the simplified assumptions made by both methods. The latter two datasets are derived from infrared radiances, so they are much less sensitive to volcanic aerosols than the ISCCP analysis. After the Mt. Pinatubo eruption, the ISCCP results indicate a dramatic decrease of thin cirrus (cloud top pressure less than 440 mb and visible optical thickness less than 1.3) over ocean, accompanied by a comparable increase of altocumulus and cumulus clouds; over land, there are no significant changes. In contrast, results from the split-window and 3I analyses show little change in thin cirrus amount over either ocean or land that is associated with the volcanic eruption. The ISCCP results can, therefore, be understood as a misclassification of thin cirrus because the additional reflected sunlight by the volcanic aerosol makes the cirrus clouds appear to be optically thicker. Examination of the split-window signature and the infrared emissivities from 3I show no significant change in infrared emissivity (or optical thickness). These results indicate that the Mt. Pinatubo volcanic aerosol did not have a significant systematic effect on tropical cirrus properties, but rather produced only temporary, local effects. Hence, these results indicate that there was no significant climate feedback produced by aerosol-cirrus-radiative interactions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stoessel, Chris
2013-11-13
This project developed a new high-performance R-10/high SHGC window design, reviewed market positioning and evaluated manufacturing solutions required for broad market adoption. The project objectives were accomplished by: identifying viable technical solutions based on modeling of modern and potential coating stacks and IGU designs; development of new coating material sets for HM thin film stacks, as well as improved HM IGU designs to accept multiple layers of HM films; matching promising new coating designs with new HM IGU designs to demonstrate performance gains; and, in cooperation with a window manufacturer, assess the potential for high-volume manufacturing and cost efficiency ofmore » a HM-based R-10 window with improved solar heat gain characteristics. A broad view of available materials and design options was applied to achieve the desired improvements. Gated engineering methodologies were employed to guide the development process from concept generation to a window demonstration. The project determined that a slightly de-rated window performance allows formulation of a path to achieve the desired cost reductions to support end consumer adoption.« less
NASA Astrophysics Data System (ADS)
Ivanov, O. A.; Kuzikov, S. V.; Vikharev, A. A.; Vikharev, A. L.; Lobaev, M. A.
2017-10-01
We propose a novel design of the barrier window for the output of microwave radiation at high peak and average power levels. A window based on a plate of polycrystalline CVD diamond with thin (nanometer-thick) boron-doped layers with increased conductivity is considered. Such a window, which retains the low radiation loss due to the small total thickness of the conductive layers and the high thermal conductivity inherent in diamond, prevents accumulation of a static charge on its surface, on the one hand, and allows one to produce a static electric field on the surface of the doped layer, which impedes the development of a multipactor discharge, on the other hand. In this case, a high level of the power of the transmitted radiation and a large passband width are ensured by choosing the configuration of the field in the form of a traveling wave inside the window.
Marko, Michael; Meng, Xing; Hsieh, Chyongere; Roussie, James; Striemer, Christopher
2013-01-01
Imaging with Zernike phase plates is increasingly being used in cryo-TEM tomography and cryo-EM single-particle applications. However, rapid ageing of the phase plates, together with the cost and effort in producing them, present serious obstacles to widespread adoption. We are experimenting with phase plates based on silicon chips that have thin windows; such phase plates could be mass-produced and made available at moderate cost. The windows are coated with conductive layers to reduce charging, and this considerably extends the useful life of the phase plates compared to traditional pure-carbon phase plates. However, a compromise must be reached between robustness and transmission through the phase-plate film. Details are given on testing phase-plate performance by means of imaging an amorphous thin film and evaluating the power spectra of the images. PMID:23994351
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ader, C.; Voirin, E.; McGee, M.
An error was found in an edge stress coefficient used to calculate stresses in thin windows. This error is present in “Roark’s Formulas for Stress and Strain” 7th and 8th Edition. The 6th Edition is correct. This guideline specially discusses a major difference in regards to a coefficient used in calculating the edge stress in “Roark’s Formulas for Stress and Strain” 6th Edition compared to the 7th and 8th Editions. In Chapter 10: Flat Plates under “Circular plates under distributed load producing large deflections,” Case 3, which is “Fixed and held. Uniform pressure q over entire plate.” The coefficient formore » a fixed edge condition in the 6th Edition1 K4 = 0.476 while in the 7th and 8th Edition2, the coefficient is 1.73 which is significant difference.« less
Bae, Jin-Hyuk; Yi, Jaeyoung; Kim, Sungtae; Shim, June-Sung; Lee, Keun-Woo
2014-01-01
Cutting efficiency is one of the most important factors to consider when a specific dental diamond rotary instrument is selected. However, the selection of a dental diamond rotary instrument is based on clinical experience rather than any scientific evidence. The purpose of this study was to identify how the cutting efficiency of different types of dental diamond rotary instrument changed with repeated cuts and disinfection. Four types of diamond rotary instrument from 2 dental manufacturers (Shofu, Jin Dental) were investigated with a high-speed air-turbine handpiece. The groups were as follows: S cham group (n=10): chamfer design from Shofu; J cham group (n=10): chamfer design from Jin Dental; S thin group (n=10): thin tapered design from Shofu; J thin group (n=10): thin tapered design from Jin Dental. Changes in the cutting efficiency of diamond rotary instruments on glass ceramic blocks were measured after repeated cuts. Changes in cutting efficiency also were measured for 30 diamond rotary instruments, the same type as those used in group J cham after disinfection with ethylene oxide gas, immersion in solution, or autoclaving. One-way ANOVA, 2-way ANOVA, and repeated-measures ANOVA were used to identify differences in cutting efficiency, in total cutting efficiency, and change trend in cutting efficiency (α=.05). The Tukey honestly significant difference method was used for the post hoc tests. The principal metal components of the diamond rotary instruments were detected with x-ray spectrometry. The mean (standard deviation [SD]) total cutting efficiency after 10 cuts in the 4 groups was in the following order: J cham group (0.210 ± 0.064 g/min) > S cham group (0.170 ± 0.064 g/min) > J thin group (0.130 ± 0.042 g/min) > S thin group (0.010 ± 0.040 g/min) (P<.05).The decrease in the cutting efficiency was greatest after the first cut. The cutting efficiency was not influenced by repeated disinfection. The cutting efficiencies of diamond rotary instruments with different designs and particle sizes showed a decreasing trend after repeated cuts but did not show any change after various disinfecting procedures. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.
Al-/Ga-Doped ZnO Window Layers for Highly Efficient Cu₂ZnSn(S,Se)₄ Thin Film Solar Cells.
Seo, Se Won; Seo, Jung Woo; Kim, Donghwan; Cheon, Ki-Beom; Lee, Doh-Kwon; Kim, Jin Young
2018-09-01
The successful use of Al-/Ga-doped ZnO (AGZO) thin films as a transparent conducting oxide (TCO) layer of a Cu2ZnSn(S,Se)4 (CZTSSe) thin film solar cell is demonstrated. The AGZO thin films were prepared by radio frequency (RF) sputtering. The structural, crystallographic, electrical, and optical properties of the AGZO thin films were systematically investigated. The photovoltaic properties of CZTSSe thin film solar cells incorporating the AGZO-based TCO layer were also reported. It has been found that the RF power and substrate temperature of the AGZO thin film are important factors determining the electrical, optical, and structural properties. The optimization process involving the RF power and the substrate temperature leads to good electrical and optical transmittance of the AGZO thin films. Finally, the CZTSSe solar cell with the AGZO TCO layer demonstrated a high conversion efficiency of 9.68%, which is higher than that of the conventional AZO counterpart by 12%.
First Light from the Far-Infrared Spectroscopy of the Troposphere (FIRST) Instrument
NASA Technical Reports Server (NTRS)
Mlynczak, Martin G.; Johnson, David G.; Latvakoski, Harri; Jucks, Kenneth; Watson, Mike; Bingham, Gail; Kratz, David P.; Traub, Wesley A.; Wellard, Stanley J.; Hyde, Charles R.;
2005-01-01
We present first light spectra from the new Far-Infrared Spectroscopy of the Troposphere (FIRST) instrument. FIRST is a Fourier Transform Spectrometer developed to measure accurately the far-infrared (15 to 100 micrometers; 650 to 100 wavenumbers) emission spectrum of the Earth and its atmosphere. The observations presented here were obtained during a high altitude balloon flight from Ft. Sumner, New Mexico on 7 June 2005. The flight data demonstrate the instrument's ability to observe the entire energetically significant infrared emission spectrum (50 to 2000 wavenumbers) at high spectral and spatial resolution on a single focal plane in an instrument with one broad spectral bandpass beamsplitter. Comparisons with radiative transfer calculations demonstrate that FIRST accurately observes the very fine spectral structure in the far-infrared. Comparisons of the atmospheric window radiances measured by FIRST and by instruments on the NASA Aqua satellite that overflew FIRST are in excellent agreement. FIRST opens a new window on the spectrum that can be used for studying atmospheric radiation and climate, cirrus clouds, and water vapor in the upper troposphere.
21 CFR 862.2270 - Thin-layer chromatography system for clinical use.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Thin-layer chromatography system for clinical use... Instruments § 862.2270 Thin-layer chromatography system for clinical use. (a) Identification. A thin-layer... a mixture. The mixture of compounds is absorbed onto a stationary phase or thin layer of inert...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rodríguez, C.A.; Sandoval-Paz, M.G.; Cabello, G.
Highlights: • High quality ZnS thin films have been deposited by chemical bath deposition technique from a non-toxic precursor’s solution. • Nanocrystalline ZnS thin films with large band gap energy were synthesized without using ammonia. • Evidence that the growing of the thin films is carried out by means of hydroxide mechanism was found. • The properties of these ZnS thin films are similar and in some cases better than the corresponding ones produced using toxic precursors such as ammonia. - Abstract: In solar cells, ZnS window layer deposited by chemical bath technique can reach the highest conversion efficiency; however,more » precursors used in the process normally are materials highly volatile, toxic and harmful to the environment and health (typically ammonia and hydrazine). In this work the characterization of ZnS thin films deposited by chemical bath in a non-toxic alkaline solution is reported. The effect of deposition technique (growth in several times) on the properties of the ZnS thin film was studied. The films exhibited a high percentage of optical transmission (greater than 80%); as the deposition time increased a decreasing in the band gap values from 3.83 eV to 3.71 eV was observed. From chemical analysis, the presence of ZnS and Zn(OH){sub 2} was identified and X-ray diffraction patterns exhibited a clear peak corresponding to ZnS hexagonal phase (1 0 3) plane, which was confirmed by electron diffraction patterns. From morphological studies, compact samples with well-defined particles, low roughness, homogeneous and pinhole-free in the surface were observed. From obtained results, it is evident that deposits of ZnS–CBD using a non-toxic solution are suitable as window layer for TFSC.« less
Reflex Triode X-Ray Source Research on Gamble
2007-06-01
dosimeters ( TLDs ) located at the vacuum window (18-27 cm from the converter), near the pinhole camera and near the image plate. II. EXPERIMENTAL...MeV- electron beams to thin converters in order to optimize emission of sub-100- keV x-rays. Thin converters reduce self-absorption of low-energy...x-rays, but the beam electrons must pass many times through the converter for efficient x-ray production. The triode configuration was found to be
Bhandarkar, Suhas; Fair, Jim; Haid, Ben; ...
2018-01-19
Many of the early cryogenic shots on NIF were plagued by buildup of considerable mass of extraneous ice on the LEH windows, a consequence of condensation of the residual air in the surrounding chamber. Thickness of this ice depended on the exact chamber pressure and the target fielding time duration, both extremely difficult to keep constant given the broad range of target types being shot. In this paper, we describe our work in designing a robust solution in the form of a second thin film that shielded the LEH window from the contaminating ice. Several detailed cryogenic considerations were requiredmore » to ensure the proper functioning of this new window, which were simulated and verified experimentally. Data from numerous subsequent shots showed marked improvement in performance, which made this new feature an essential component for all cryogenic NIF targets.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhandarkar, Suhas; Fair, Jim; Haid, Ben
Many of the early cryogenic shots on NIF were plagued by buildup of considerable mass of extraneous ice on the LEH windows, a consequence of condensation of the residual air in the surrounding chamber. Thickness of this ice depended on the exact chamber pressure and the target fielding time duration, both extremely difficult to keep constant given the broad range of target types being shot. In this paper, we describe our work in designing a robust solution in the form of a second thin film that shielded the LEH window from the contaminating ice. Several detailed cryogenic considerations were requiredmore » to ensure the proper functioning of this new window, which were simulated and verified experimentally. Data from numerous subsequent shots showed marked improvement in performance, which made this new feature an essential component for all cryogenic NIF targets.« less
Scale model testing of drogues for free drifting buoys
NASA Technical Reports Server (NTRS)
Vachon, W. A.
1973-01-01
Instrumented model drogue tests were conducted in a ship model towing tank. The purpose of the tests was to observe and measure deployment and drag characteristics of such shapes as parachutes, crossed vanes, and window shades which may be employed in conjunction with free drifting buoys. Both Froude and Reynolds scaling laws were applied while scaling to full scale relative velocities of from 0 to 0.2 knots. A weighted window shade drogue is recommended because of its performance, high drag coefficient, simplicity, and low cost. Detailed theoretical performance curves are presented for parachutes, crossed vanes, and window shade drogues. Theoretical estimates of depth locking accuracy and buoy-induced dynamic loads pertinent to window shade drogues are presented as a design aid. An example of a window shade drogue design is presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ong, Hui-Yng; School of Engineering, Nanyang Polytechnic, Singapore 569830; Shrestha, Milan
2015-09-28
Indium-tin-oxide (ITO) thin films are perceived to be stiff and brittle. This letter reports that crumpled ITO thin films on adhesive poly-acrylate dielectric elastomer can make compliant electrodes, sustaining compression of up to 25% × 25% equi-biaxial strain and unfolding. Its optical transmittance reduces with crumpling, but restored with unfolding. A dielectric elastomer actuator (DEA) using the 14.2% × 14.2% initially crumpled ITO thin-film electrodes is electrically activated to produce a 37% areal strain. Such electric unfolding turns the translucent DEA to be transparent, with transmittance increased from 39.14% to 52.08%. This transmittance tunability promises to make a low-cost smart privacy window.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fernandes, P. A.; Lynch, K. A.
Here, we define the observational parameter regime necessary for observing low-altitude ionospheric origins of high-latitude ion upflow/outflow. We present measurement challenges and identify a new analysis technique which mitigates these impediments. To probe the initiation of auroral ion upflow, it is necessary to examine the thermal ion population at 200-350 km, where typical thermal energies are tenths of eV. Interpretation of the thermal ion distribution function measurement requires removal of payload sheath and ram effects. We use a 3-D Maxwellian model to quantify how observed ionospheric parameters such as density, temperature, and flows affect in situ measurements of the thermalmore » ion distribution function. We define the viable acceptance window of a typical top-hat electrostatic analyzer in this regime and show that the instrument's energy resolution prohibits it from directly observing the shape of the particle spectra. To extract detailed information about measured particle population, we define two intermediate parameters from the measured distribution function, then use a Maxwellian model to replicate possible measured parameters for comparison to the data. Liouville's theorem and the thin-sheath approximation allow us to couple the measured and modeled intermediate parameters such that measurements inside the sheath provide information about plasma outside the sheath. We apply this technique to sounding rocket data to show that careful windowing of the data and Maxwellian models allows for extraction of the best choice of geophysical parameters. More widespread use of this analysis technique will help our community expand its observational database of the seed regions of ionospheric outflows.« less
Observations in the 1.3 and 1.5 THz atmospheric windows with the Receiver Lab Telescope
NASA Technical Reports Server (NTRS)
Marrone, Daniel P.; Blundell, Raymond; Tong, Edward; Paine, Scott N.; Loudkov, Denis; Kawamura, Jonathan H.; Luhr, Daniel; Barrientos, Claudio
2005-01-01
The Receiver Lab Telescope (RLT) is a groundbased terahertz telescope; it is currently the only instrument producing astronomical data between 1 and 2 THz. The capabilities of the RLT have been expanding since observations began in late 2002. Initial observations were limited to the 850 GHz and 1.03 THz windows due to the availability of solid state local oscillators. In the last year we have begun observations with new local oscillators for the 1.3 and 1.5 THz atmospheric windows.
Janneck, Robby; Vercesi, Federico; Heremans, Paul; Genoe, Jan; Rolin, Cedric
2016-09-01
A model that describes solvent evaporation dynamics in meniscus-guided coating techniques is developed. In combination with a single fitting parameter, it is shown that this formula can accurately predict a processing window for various coating conditions. Organic thin-film transistors (OTFTs), fabricated by a zone-casting setup, indeed show the best performance at the predicted coating speeds with mobilities reaching 7 cm 2 V -1 s -1 . © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Farrington, Robert B.; Anderson, Ren
2001-01-01
The cabin cooling system includes a cooling duct positioned proximate and above upper edges of one or more windows of a vehicle to exhaust hot air as the air is heated by inner surfaces of the windows and forms thin boundary layers of heated air adjacent the heated windows. The cabin cooling system includes at least one fan to draw the hot air into the cooling duct at a flow rate that captures the hot air in the boundary layer without capturing a significant portion of the cooler cabin interior air and to discharge the hot air at a point outside the vehicle cabin, such as the vehicle trunk. In a preferred embodiment, the cooling duct has a cross-sectional area that gradually increases from a distal point to a proximal point to the fan inlet to develop a substantially uniform pressure drop along the length of the cooling duct. Correspondingly, this cross-sectional configuration develops a uniform suction pressure and uniform flow rate at the upper edge of the window to capture the hot air in the boundary layer adjacent each window.
Fabrication of glass gas cells for the HALOE and MAPS satellite experiments
NASA Technical Reports Server (NTRS)
Sullivan, E. M.; Walthall, H. G.
1984-01-01
The Halogen Occultation Experiment (HALOE) and the Measurement of Air Pollution from Satellites (MAPS) experiment are satellite-borne experiments which measure trace constituents in the Earth's atmosphere. The instruments which obtain the data for these experiments are based on the gas filter correlation radiometer measurement technique. In this technique, small samples of the gases of interest are encapsulated in glass cylinders, called gas cells, which act as very selective optical filters. This report describes the techniques employed in the fabrication of the gas cells for the HALOE and MAPS instruments. Details of the method used to fuse the sapphire windows (required for IR transmission) to the glass cell bodies are presented along with detailed descriptions of the jigs and fixtures used during the assembly process. The techniques and equipment used for window inspection and for pairing the HALOE windows are discussed. Cell body materials and the steps involved in preparing the cell bodies for the glass-to-sapphire fusion process are given.
Inter-Comparison of GOES-8 Imager and Sounder Skin Temperature Retrievals
NASA Technical Reports Server (NTRS)
Haines, Stephanie L.; Suggs, Ronnie J.; Jedlovec, Gary J.; Arnold, James E. (Technical Monitor)
2001-01-01
Skin temperature (ST) retrievals derived from geostationary satellite observations have both high temporal and spatial resolutions and are therefore useful for applications such as assimilation into mesoscale forecast models, nowcasting, and diagnostic studies. Our retrieval method uses a Physical Split Window technique requiring at least two channels within the longwave infrared window. On current GOES satellites, including GOES-11, there are two Imager channels within the required spectral interval. However, beginning with the GOES-M satellite the 12-um channel will be removed, leaving only one longwave channel. The Sounder instrument will continue to have three channels within the longwave window, and therefore ST retrievals will be derived from Sounder measurements. This research compares retrievals from the two instruments and evaluates the effects of the spatial resolution and sensor calibration differences on the retrievals. Both Imager and Sounder retrievals are compared to ground-truth data to evaluate the overall accuracy of the technique. An analysis of GOES-8 and GOES-11 intercomparisons is also presented.
Improved outgassing models for the Landsat-5 thematic mapper
Micijevic, E.; Chander, G.; Hayes, R.W.
2007-01-01
The Landsat-5 (L5) Thematic Mapper (TM) detectors of the short wave infrared (SWIR) bands 5 and 7 are maintained on cryogenic temperatures to minimize thermal noise and allow adequate detection of scene energy. Over the instrument's lifetime, gain oscillations are observed in these bands that are caused by an ice-like contaminant that gradually builds up on the window of a dewar that houses these bands' detectors. This process of icing, an effect of material outgassing in space, is detected and characterized through observations of Internal Calibrator (IC) data. Analyses of IC data indicated three to five percent uncertainty in absolute gain estimates due to this icing phenomenon. The thin-film interference lifetime models implemented in the image product generation systems at the U.S. Geological Survey (USGS) Center for Earth Resources Observation and Science (EROS) successfully remove up to 80 percent of the icing effects for the image acquisition period from the satellite's launch in 1984 until 2001; however, their correction ability was found to be much lower for the time thereafter. This study concentrates on improving the estimates of the contaminant film growth rate and the associated change in the period of gain oscillations. The goal is to provide model parameters with the potential to correct 70 to 80 percent of gain uncertainties caused by outgassing effects in L5 TM bands 5 and 7 over the instrument's entire lifetime. ?? 2007 IEEE.
Improved outgassing models for the Landsat-5 thematic mapper
Micijevic, E.; Chander, G.; Hayes, R.W.
2008-01-01
The Landsat-5 (L5) Thematic Mapper (TM) detectors of the short wave infrared (SWIR) bands 5 and 7 are maintained on cryogenic temperatures to minimize thermal noise and allow adequate detection of scene energy. Over the instrument's lifetime, gain oscillations are observed in these bands that are caused by an ice-like contaminant that gradually builds up on the window of a dewar that houses these bands' detectors. This process of icing, an effect of material outgassing in space, is detected and characterized through observations of Internal Calibrator (IC) data. Analyses of IC data indicated three to five percent uncertainty in absolute gain estimates due to this icing phenomenon. The thin-film interference lifetime models implemented in the image product generation systems at the U.S. Geological Survey (USGS) Center for Earth Resources Observation and Science (EROS) successfully remove up to 80 percent of the icing effects for the image acquisition period from the satellite's launch in 1984 until 2001; however, their correction ability was found to be much lower for the time thereafter. This study concentrates on improving the estimates of the contaminant film growth rate and the associated change in the period of gain oscillations. The goal is to provide model parameters with the potential to correct 70 to 80 percent of gain uncertainties caused by outgassing effects in L5 TM bands 5 and 7 over the instrument's entire lifetime. ?? 2007 IEEE.
Optical Studies of Pure Fluids about Their Critical Points
NASA Astrophysics Data System (ADS)
Pang, Kian Tiong
Three optical experiments were performed on pure fluids near their critical points. In the first two setups, CH_3F and H_2C:CF _2 were each tested in a temperature -controlled, prism-shaped cell and a thin parallel-windows cell. In the prism cell, a laser beam was additionally deflected by the fluid present. From the deflection data, the refractive index was related to the density to find the Lorentz-Lorenz function. Critical temperature (T _{c}), density, refractive index and electronic polarizability were found. In the second experiment, a critically-filled, thin parallel-windows cell was placed in one arm of a Mach-Zehnder interoferometer. Fluid density was monitored by changes in the fringe pattern with changing cell temperature. The aim was to improve on the precision of T_{c}: T_{c}{rm (CH}_3 F) = (44cdot9087 +/- 0cdot0002)C; T _{c}{rm(H}_2C:CF _2) = (29cdot7419 +/- 0cdot0001)C; and, to study the coexistence curve and diameter as close to T_{c} as possible. The critical behaviour was compared to the theoretical renormalization group calculations. The derived coefficients were tested against a proposed three-body interaction to explain the field-mixing term in the diameter near the critical point. It was found that H_2C:CF_2 behaved as predicted by such an interaction; CH _3F (and CHF_3) did not. The third experiment was a feasibility study to find out if (critical) isotherms could be measured optically in a setup which combined the prism and parallel-windows cells. The aim was to map isotherms in as wide a range of pressure and density as possible and to probe the critical region directly. Pressure was monitored by a precise digital pressure gauge. CH_3F and CHF _3 were tested in this system. It was found that at low densities, the calculated second and third virial coefficients agreed with reference values. However, the data around the critical point were not accurate enough for use to calculate the critical exponent, delta . The calculated value was consistently smaller than the expected value. It was believed that the present setup had thermal isolation problems. Suggestions were made as to the improvements of this isotherm cell setup. Lastly, a joint project with the Department of Ophthalmology, UBC to assemble a vitreous fluorophotometer is discussed in Appendix F. The upgrading of the instrument took up the initial two years of this PhD programme.
Exercise Balikatan 2012 Technology Insertion Quicklook Report
2012-05-15
expanded polystyrene panels covered with a thin layer of cement, sand, fiberglass, and other additives. A permanent 200 sq ft building with windows... Expanded Polystyrene 1.5# density pre-cut panels and GFRC -Glass Fiber Reinforced Concrete Structural coating (Fiberglass Mesh, Portland Cement, Silica
The Mars oxidant experiment (MOx) for Mars '96
NASA Technical Reports Server (NTRS)
McKay, C. P.; Grunthaner, F. J.; Lane, A. L.; Herring, M.; Bartman, R. K.; Ksendzov, A.; Manning, C. M.; Lamb, J. L.; Williams, R. M.; Ricco, A. J.;
1998-01-01
The MOx instrument was developed to characterize the reactive nature of the martian soil. The objectives of MOx were: (1) to measure the rate of degradation of organics in the martian environment; (2) to determine if the reactions seen by the Viking biology experiments were caused by a soil oxidant and measure the reactivity of the soil and atmosphere: (3) to monitor the degradation, when exposed to the martian environment, of materials of potential use in future missions; and, finally, (4) to develop technologies and approaches that can be part of future soil analysis instrumentation. The basic approach taken in the MOx instrument was to place a variety of materials composed as thin films in contact with the soil and monitor the physical and chemical changes that result. The optical reflectance of the thin films was the primary sensing-mode. Thin films of organic materials, metals, and semiconductors were prepared. Laboratory simulations demonstrated the response of thin films to active oxidants.
Handheld White Light Interferometer for Measuring Defect Depth in Windows
NASA Technical Reports Server (NTRS)
Youngquist, Robert; Simmons, Stephen; Cox, Robert
2010-01-01
Accurate quantification of defects (scratches and impacts) is vital to the certification of flight hardware and other critical components. The amount of damage to a particular component contributes to the performance, reliability, and safety of a system, which ultimately affects the success or failure of a mission or test. The launch-commit criteria on a Space Shuttle Orbiter window are governed by the depth of the defects that are identified by a visual inspection. This measurement of a defect is not easy to obtain given the environment, size of the defect, and location of the window(s). The determination of depth has typically been performed by taking a mold impression and measuring the impression with an optical profiling instrument. Another method of obtaining an estimate of the depth is by using a refocus microscope. To use a refocus microscope, the surface of the glass and bottom of the defect are, in turn, brought into focus by the operator. The amount of movement between the two points corresponds to the depth of the defect. The refocus microscope requires a skilled operator and has been proven to be unreliable when used on Orbiter windows. White light interferometry was chosen as a candidate to replace the refocus microscope. The White Light Interferometer (WLI) was developed to replace the refocus microscope as the instrument used for measuring the depth of defects in Orbiter windows. The WLI consists of a broadband illumination source, interferometer, detector, motion control, displacement sensor, mechanical housing, and support electronics. The illumination source for the WLI is typically a visible light emitting diode (LED) or a near-infrared superluminescent diode (SLD) with power levels of less than a milliwatt. The interferometer is a Michelson configuration consisting of a 1-in. (2.5-cm) cube beam splitter, a 0.5-in. (1.3-cm) optical window as a movable leg (used to closely match the return intensity of the fixed leg from the window), and a mirrored prism to fold the optics into the mechanical housing. The detector may be one of many C-mount CCD (charge-coupled device) cameras. Motion is provided by a commercial nanostepping motor with a serial interface. The displacement sensor is a custom device specifically designed for this application. The mechanical housing and support electronics were designed to integrate the various components into an instrument that could be physically handled by a technician and easily transported.
Hydrothermally formed three-dimensional nanoporous Ni(OH)2 thin-film supercapacitors.
Yang, Yang; Li, Lei; Ruan, Gedeng; Fei, Huilong; Xiang, Changsheng; Fan, Xiujun; Tour, James M
2014-09-23
A three-dimensional nanoporous Ni(OH)2 thin-film was hydrothermally converted from an anodically formed porous layer of nickel fluoride/oxide. The nanoporous Ni(OH)2 thin-films can be used as additive-free electrodes for energy storage. The nanoporous layer delivers a high capacitance of 1765 F g(-1) under three electrode testing. After assembly with porous activated carbon in asymmetric supercapacitor configurations, the devices deliver superior supercapacitive performances with capacitance of 192 F g(-1), energy density of 68 Wh kg(-1), and power density of 44 kW kg(-1). The wide working potential window (up to 1.6 V in 6 M aq KOH) and stable cyclability (∼90% capacitance retention over 10,000 cycles) make the thin-film ideal for practical supercapacitor devices.
Ultrathin Fluidic Laminates for Large‐Area Façade Integration and Smart Windows
Heiz, Benjamin P. V.; Pan, Zhiwen; Lautenschläger, Gerhard; Sirtl, Christin; Kraus, Matthias
2016-01-01
Buildings represent more than 40% of Europe's energy demands and about one third of its CO2 emissions. Energy efficient buildings and, in particular, building skins have therefore been among the key priorities of international research agendas. Here, glass–glass fluidic devices are presented for large‐area integration with adaptive façades and smart windows. These devices enable harnessing and dedicated control of various liquids for added functionality in the building envelope. Combining a microstructured glass pane, a thin cover sheet with tailored mechanical performance, and a liquid for heat storage and transport, a flat‐panel laminate is generated with thickness adapted to a single glass sheet in conventional windows. Such multimaterial devices can be integrated with state‐of‐the‐art window glazings or façades to harvest and distribute thermal as well as solar energy by wrapping buildings into a fluidic layer. High visual transparency is achieved through adjusting the optical properties of the employed liquid. Also secondary functionality, such as chromatic windows, polychromatism, or adaptive energy uptake can be generated on part of the liquid. PMID:28331790
Ultrathin Fluidic Laminates for Large-Area Façade Integration and Smart Windows.
Heiz, Benjamin P V; Pan, Zhiwen; Lautenschläger, Gerhard; Sirtl, Christin; Kraus, Matthias; Wondraczek, Lothar
2017-03-01
Buildings represent more than 40% of Europe's energy demands and about one third of its CO 2 emissions. Energy efficient buildings and, in particular, building skins have therefore been among the key priorities of international research agendas. Here, glass-glass fluidic devices are presented for large-area integration with adaptive façades and smart windows. These devices enable harnessing and dedicated control of various liquids for added functionality in the building envelope. Combining a microstructured glass pane, a thin cover sheet with tailored mechanical performance, and a liquid for heat storage and transport, a flat-panel laminate is generated with thickness adapted to a single glass sheet in conventional windows. Such multimaterial devices can be integrated with state-of-the-art window glazings or façades to harvest and distribute thermal as well as solar energy by wrapping buildings into a fluidic layer. High visual transparency is achieved through adjusting the optical properties of the employed liquid. Also secondary functionality, such as chromatic windows, polychromatism, or adaptive energy uptake can be generated on part of the liquid.
An instrument for spatial conductivity measurements of high Tc superconducting (HTSC) materials
NASA Technical Reports Server (NTRS)
Vansant, T.
1991-01-01
High T(sub c) Superconducting (HTSC) thin films are suggested for use in a number of aerospace applications such as an IR bolometer and as electromagnetic shielding. As part of its flight assurance role, the Materials Branch of the Goddard Space Flight Center has initiated development of an instrument capable of measuring variations in conductivity for flat samples using an eddy current testing device and an X-Y positioning table. This instrument was used to examine bulk HTSC samples. System changes that would enable characterization of thin film materials are discussed.
NASA Technical Reports Server (NTRS)
Strekalov, Dmitry; Matsko, Andrey; Savchenkov, Anatoliy; Maleki, Lute
2008-01-01
Coaxial electric heaters have been conceived for use in highly sensitive instruments in which there are requirements for compact heaters but stray magnetic fields associated with heater electric currents would adversely affect operation. Such instruments include atomic clocks and magnetometers that utilize heated atomic-sample cells, wherein stray magnetic fields at picotesla levels could introduce systematic errors into instrument readings. A coaxial electric heater is essentially an axisymmetric coaxial cable, the outer conductor of which is deliberately made highly electrically resistive so that it can serve as a heating element. As in the cases of other axisymmetric coaxial cables, the equal magnitude electric currents flowing in opposite directions along the inner and outer conductors give rise to zero net magnetic field outside the outer conductor. Hence, a coaxial electric heater can be placed near an atomic-sample cell or other sensitive device. A coaxial electric heater can be fabricated from an insulated copper wire, the copper core of which serves as the inner conductor. For example, in one approach, the insulated wire is dipped in a colloidal graphite emulsion, then the emulsion-coated wire is dried to form a thin, uniform, highly electrically resistive film that serves as the outer conductor. Then the film is coated with a protective layer of high-temperature epoxy except at the end to be electrically connected to the power supply. Next, the insulation is stripped from the wire at that end. Finally, electrical leads from the heater power supply are attached to the exposed portions of the wire and the resistive film. The resistance of the graphite film can be tailored via its thickness. Alternatively, the film can be made from an electrically conductive paint, other than a colloidal graphite emulsion, chosen to impart the desired resistance. Yet another alternative is to tailor the resistance of a graphite film by exploiting the fact that its resistance can be changed permanently within about 10 percent by heating it to a temperature above 300 C. A coaxial heater, with electrical leads attached, that has been bent into an almost full circle for edge heating of a circular window is shown. (In the specific application, there is a requirement for a heated cell window, through which an optical beam enters the cell.)
Arcjet exploratory tests of ARC optical window design for the AFE vehicle
NASA Technical Reports Server (NTRS)
Whiting, Ellis E.; Terrazas-Salinas, Imelda; Craig, Roger A.; Sobeck, Charles K.; Sarver, George L., III; Salerno, Louis J.; Love, Wendell; Maa, Scott; Covington, AL
1991-01-01
Tests were made in the 20 MW arc jet facility at the NASA ARC to determine the suitability of sapphire and fused silica as window materials for the Aeroassist Flight Experiment (AFE) entry vehicle. Twenty nine tests were made; 25 at a heating rate about 80 percent of that expected during the AFE entry and 4 at approximately the full, 100 percent AFE heating rate profile, that produces a temperature of about 2900 F on the surface of the tiles that protect the vehicle. These tests show that a conductively cooled window design using mechanical thermal contacts and sapphire is probably not practical. Cooling the window using mechanical thermal contacts produces thermal stresses in the sapphire that cause the window to crack. An insulated design using sapphire, that cools the window as little as possible, appears promising although some spectral data in the vacuum-ultra-violet (VUV) will be lost due to the high temperature reached by the sapphire. The surface of the insulated sapphire windows, tested at the 100 percent AFE heating rate, showed some slight ablation, and cracks appeared in two of three test windows. One small group of cracks were obviously caused by mechanical binding of the window in the assembly, which can be eliminated with improved design. Other cracks were long, straight, thin crystallographic cracks that have very little effect on the optical transmission of the window. Also, the windows did not fall apart along these crystallographic cracks when the windows were removed from their assemblies. Theoretical results from the thermal analysis computer program SINDA indicate that increasing the window thickness from 4 to 8 mm may enable surface ablation to be avoided. An insulated design using a fused silica window tested at the nominal AFE heating rate experienced severe ablation, thus fused silica is not considered to be an acceptable window material.
2. CHANNEL DIMENSIONS AND ALIGNMENT RESEARCH INSTRUMENTATION. HYDRAULIC ENGINEER PILOTING ...
2. CHANNEL DIMENSIONS AND ALIGNMENT RESEARCH INSTRUMENTATION. HYDRAULIC ENGINEER PILOTING VIDEO-CONTROLED BOAT MODEL FROM CONTROL TRAILER. NOTE VIEW FROM BOAT-MOUNTED VIDEO CAMERA SHOWN ON MONITOR, AND MODEL WATERWAY VISIBLE THROUGH WINDOW AT LEFT. - Waterways Experiment Station, Hydraulics Laboratory, Halls Ferry Road, 2 miles south of I-20, Vicksburg, Warren County, MS
Looking out the port/foward looking window of the Docking Compartment
2009-05-15
ISS019-E-017603 (15 May 2009) --- Backdropped by the thin line of Earth?s atmosphere and the blackness of space, a portion of the International Space Station is featured in this image photographed by an Expedition 19 crewmember aboard the station.
Simple Chemical Vapor Deposition Experiment
ERIC Educational Resources Information Center
Pedersen, Henrik
2014-01-01
Chemical vapor deposition (CVD) is a process commonly used for the synthesis of thin films for several important technological applications, for example, microelectronics, hard coatings, and smart windows. Unfortunately, the complexity and prohibitive cost of CVD equipment makes it seldom available for undergraduate chemistry students. Here, a…
High quality nitrogen-doped zinc oxide thin films grown on ITO by sol-gel method
NASA Astrophysics Data System (ADS)
Pathak, Trilok Kumar; Kumar, Vinod; Purohit, L. P.
2015-11-01
Highly transparent N-doped ZnO thin films were deposited on ITO coated corning glass substrate by sol-gel method. Ammonium nitrate was used as a dopant source of N with varying the doping concentration 0, 0.5, 1.0, 2.0 and 3.0 at%. The DSC analysis of prepared NZO sols is observed a phase transition at 150 °C. X-ray diffraction pattern showed the preferred (002) peak of ZnO, which was deteriorated with increased N concentrations. The transmittance of NZO thin films was observed to be ~88%. The bandgap of NZO thin films increased from 3.28 to 3.70 eV with increased N concentration from 0 to 3 at%. The maximum carrier concentration 8.36×1017 cm-3 and minimum resistivity 1.64 Ω cm was observed for 3 at% N doped ZnO thin films deposited on glass substrate. These highly transparent ZnO thin films can be used as a window layer in solar cells and optoelectronic devices.
NASA Astrophysics Data System (ADS)
Cassir, Michel; Goubin, Fabrice; Bernay, Cécile; Vernoux, Philippe; Lincot, Daniel
2002-06-01
Ultra thin films of ZrO 2 were synthesized on soda lime glass and SnO 2-coated glass, using ZrCl 4 and H 2O precursors by atomic layer deposition (ALD), a sequential CVD technique allowing the formation of dense and homogeneous films. The effect of temperature on the film growth kinetics shows a first temperature window for ALD processing between 280 and 350 °C and a second regime or "pseudo-window" between 380 and 400 °C, with a growth speed of about one monolayer per cycle. The structure and morphology of films of less than 1 μm were characterized by XRD and SEM. From 275 °C, the ZrO 2 film is crystallized in a tetragonal form while a mixture of tetragonal and monoclinic phases appears at 375 °C. Impedance spectroscopy measurements confirmed the electrical properties of ZrO 2 and the very low porosity of the deposited layer.
NASA Astrophysics Data System (ADS)
Wang, Tai-Min; Chien, Wei-Yu; Hsu, Chia-Ling; Lin, Chrong Jung; King, Ya-Chin
2018-04-01
In this paper, we present a new differential p-channel multiple-time programmable (MTP) memory cell that is fully compatible with advanced 16 nm CMOS fin field-effect transistors (FinFET) logic processes. This differential MTP cell stores complementary data in floating gates coupled by a slot contact structure, which make different read currents possible on a single cell. In nanoscale CMOS FinFET logic processes, the gate dielectric layer becomes too thin to retain charges inside floating gates for nonvolatile data storage. By using a differential architecture, the sensing window of the cell can be extended and maintained by an advanced blanket boost scheme. The charge retention problem in floating gate cells can be improved by periodic restoring lost charges when significant read window narrowing occurs. In addition to high programming efficiency, this p-channel MTP cells also exhibit good cycling endurance as well as disturbance immunity. The blanket boost scheme can remedy the charge loss problem under thin gate dielectrics.
NASA Astrophysics Data System (ADS)
Chen, Ying-Chih; Su, Yan-Kuin; Yu, Hsin-Chieh; Huang, Chun-Yuan; Huang, Tsung-Syun
2011-10-01
A wide hysteresis width characteristic (memory window) was observed in the organic thin film transistors (OTFTs) using poly(2-hydroxyethyl methacrylate) (PHEMA)-based polymer multilayers. In this study, a strong memory effect was also found in the pentacene-based OTFTs and the electric characteristics were improved by introducing PHEMA/poly(methyl methacrylate) (PMMA)/PHEMA trilayer to replace the conventional PHEMA monolayer or PMMA/PHEMA and PHEMA/PMMA bilayer as the dielectric layers of OTFTs. The memory effect was originated from the electron trapping and slow polarization of the dielectrics. The hydroxyl (-OH) groups inside the polymer dielectric were the main charge storage sites of the electrons. This charge-storage phenomenon could lead to a wide flat-band voltage shift (memory window, △VFB = 22 V) which is essential for the OTFTs' memory-related applications. Moreover, the fabricated transistors also exhibited significant switchable channel current due to the charge-storage and slow charge relaxation.
Variable transmittance electrochromic windows
NASA Astrophysics Data System (ADS)
Rauh, R. D.
1983-11-01
Electrochromic apertures based on RF sputtered thin films of WO3 are projected to have widely different sunlight attenuation properties when converted to MxWO3 (M = H, Li, Na, Ag, etc.), depending on the initial preparation conditions. Amorphous WO3, prepared at low temperature, has a coloration spectrum centered in the visible, while high temperature crystalline WO3 attenuates infrared light most efficiently, but appears to become highly reflective at high values of x. The possibility therefore exists of producing variable light transmission apertures of the general form (a-MxWO3/FIC/c-WO3), where the FIC is an ion conducting thin film, such as LiAlF4 (for M = Li). The attenuation of 90% of the solar spectrum requires an injected charge of 30 to 40 mcoul/sq cm in either amorphous or crystalline WO3, corresponding to 0.2 Whr/sq m per coloration cycle. In order to produce windows with very high solar transparency in the bleached form, new counter electrode materials must be found with complementary electrochromism to WO3.
Plasma interactions determine the composition in pulsed laser deposited thin films
NASA Astrophysics Data System (ADS)
Chen, Jikun; Döbeli, Max; Stender, Dieter; Conder, Kazimierz; Wokaun, Alexander; Schneider, Christof W.; Lippert, Thomas
2014-09-01
Plasma chemistry and scattering strongly affect the congruent, elemental transfer during pulsed laser deposition of target metal species in an oxygen atmosphere. Studying the plasma properties of La0.6Sr0.4MnO3, we demonstrate for as grown La0.6Sr0.4MnO3-δ films that a congruent transfer of metallic species is achieved in two pressure windows: ˜10-3 mbar and ˜2 × 10-1 mbar. In the intermediate pressure range, La0.6Sr0.4MnO3-δ becomes cation deficient and simultaneously almost fully stoichiometric in oxygen. Important for thin film growth is the presence of negative atomic oxygen and under which conditions positive metal-oxygen ions are created in the plasma. This insight into the plasma chemistry shows why the pressure window to obtain films with a desired composition and crystalline structure is narrow and requires a careful adjustment of the process parameters.
Emissivity of freestanding membranes with thin metal coatings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zwol, P. J. van, E-mail: Pieter-jan.van.zwol@asml.com; Vles, D. F.; Voorthuijzen, W. P.
Freestanding silicon nitride membranes with thicknesses down to a few tens of nanometers find use as TEM windows or soft X-ray spectral purity filters. As the thickness of a membrane decreases, emissivity vanishes, which limits radiative heat emission and resistance to heat loads. We show that thin metal layers with thicknesses in the order of 1 nm enhance the emissivity of thin membranes by two to three orders of magnitude close to the theoretical limit of 0.5. This considerably increases thermal load capacity of membranes in vacuum environments. Our experimental results are in line with classical theory in which we adaptmore » thickness dependent scattering terms in the Drude and Lorentz oscillators.« less
ERIC Educational Resources Information Center
Lundholm, Jean K.; Littrell, John M.
1986-01-01
Examined cheerleaders' desire for thinness in relationship to disordered eating and weight control behaviors. A Desire for Thinness Scale and selected scales from three eating disorder instruments were administered to 751 high school cheerleaders. Cheerleaders who expressed a strong desire for thinness had significantly higher scores on seven of…
Photonic microstructures for energy-generating clear glass and net-zero energy buildings
NASA Astrophysics Data System (ADS)
Vasiliev, Mikhail; Alghamedi, Ramzy; Nur-E-Alam, Mohammad; Alameh, Kamal
2016-08-01
Transparent energy-harvesting windows are emerging as practical building-integrated photovoltaics (BIPV), capable of generating electricity while simultaneously reducing heating and cooling demands. By incorporating spectrally-selective diffraction gratings as light deflecting structures of high visible transparency into lamination interlayers and using improved spectrally-selective thin-film coatings, most of the visible solar radiation can be transmitted through the glass windows with minimum attenuation. At the same time, the ultraviolet (UV) and a part of incident solar infrared (IR) radiation energy are converted and/or deflected geometrically towards the panel edge for collection by CuInSe2 solar cells. Experimental results show power conversion efficiencies in excess of 3.04% in 10 cm × 10 cm vertically-placed clear glass panels facing direct sunlight, and up to 2.08% in 50 cm × 50 cm installation-ready framed window systems. These results confirm the emergence of a new class of solar window system ready for industrial application.
Thermal and Lorentz Force Analysis of Beryllium Windows for the Rectilinear Muon Cooling Channel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Luo, Tianhuan; Li, D.; Virostek, S.
Reduction of the 6-dimensional phase-space of a muon beam by several orders of magnitude is a key requirement for a Muon Collider. Recently, a 12-stage rectilinear ionization cooling channel has been proposed to achieve that goal. The channel consists of a series of low frequency (325 MHz-650 MHz) normal conducting pillbox cavities, which are enclosed with thin beryllium windows (foils) to increase shunt impedance and give a higher field on-axis for a given amount of power. These windows are subject to ohmic heating from RF currents and Lorentz force from the EM field in the cavity, both of which willmore » produce out of the plane displacements that can detune the cavity frequency. In this study, using the TEM3P code, we report on a detailed thermal and mechanical analysis for the actual Be windows used on a 325 MHz cavity in a vacuum ionization cooling rectilinear channel for a Muon Collider.« less
Thermal and Lorentz force analysis of beryllium windows for a rectilinear muon cooling channel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Luo, T.; Stratakis, D.; Li, D.
Reduction of the 6-dimensional phase-space of a muon beam by several orders of magnitude is a key requirement for a Muon Collider. Recently, a 12-stage rectilinear ionization cooling channel has been proposed to achieve that goal. The channel consists of a series of low frequency (325 MHz-650 MHz) normal conducting pillbox cavities, which are enclosed with thin beryllium windows (foils) to increase shunt impedance and give a higher field on-axis for a given amount of power. These windows are subject to ohmic heating from RF currents and Lorentz force from the EM field in the cavity, both of which willmore » produce out of the plane displacements that can detune the cavity frequency. In this study, using the TEM3P code, we report on a detailed thermal and mechanical analysis for the actual Be windows used on a 325 MHz cavity in a vacuum ionization cooling rectilinear channel for a Muon Collider.« less
Photonic microstructures for energy-generating clear glass and net-zero energy buildings.
Vasiliev, Mikhail; Alghamedi, Ramzy; Nur-E-Alam, Mohammad; Alameh, Kamal
2016-08-23
Transparent energy-harvesting windows are emerging as practical building-integrated photovoltaics (BIPV), capable of generating electricity while simultaneously reducing heating and cooling demands. By incorporating spectrally-selective diffraction gratings as light deflecting structures of high visible transparency into lamination interlayers and using improved spectrally-selective thin-film coatings, most of the visible solar radiation can be transmitted through the glass windows with minimum attenuation. At the same time, the ultraviolet (UV) and a part of incident solar infrared (IR) radiation energy are converted and/or deflected geometrically towards the panel edge for collection by CuInSe2 solar cells. Experimental results show power conversion efficiencies in excess of 3.04% in 10 cm × 10 cm vertically-placed clear glass panels facing direct sunlight, and up to 2.08% in 50 cm × 50 cm installation-ready framed window systems. These results confirm the emergence of a new class of solar window system ready for industrial application.
Alghamedi, Ramzy; Vasiliev, Mikhail; Nur-E-Alam, Mohammad; Alameh, Kamal
2014-10-16
All-inorganic visibly-transparent energy-harvesting clear laminated glass windows are the most practical solution to boosting building-integrated photovoltaics (BIPV) energy outputs significantly while reducing cooling- and heating-related energy consumption in buildings. By incorporating luminophore materials into lamination interlayers and using spectrally-selective thin-film coatings in conjunction with CuInSe2 solar cells, most of the visible solar radiation can be transmitted through the glass window with minimum attenuation while ultraviolet (UV) radiation is down-converted and routed together with a significant part of infrared radiation to the edges for collection by solar cells. Experimental results demonstrate a 10 cm × 10 cm vertically-placed energy-harvesting clear glass panel of transparency exceeding 60%, invisible solar energy attenuation greater than 90% and electrical power output near 30 Wp/m(2) mainly generated by infrared (IR) and UV radiations. These results open the way for the realization of large-area visibly-transparent energy-harvesting clear glass windows for BIPV systems.
Alghamedi, Ramzy; Vasiliev, Mikhail; Nur-E-Alam, Mohammad; Alameh, Kamal
2014-01-01
All-inorganic visibly-transparent energy-harvesting clear laminated glass windows are the most practical solution to boosting building-integrated photovoltaics (BIPV) energy outputs significantly while reducing cooling- and heating-related energy consumption in buildings. By incorporating luminophore materials into lamination interlayers and using spectrally-selective thin-film coatings in conjunction with CuInSe2 solar cells, most of the visible solar radiation can be transmitted through the glass window with minimum attenuation while ultraviolet (UV) radiation is down-converted and routed together with a significant part of infrared radiation to the edges for collection by solar cells. Experimental results demonstrate a 10 cm × 10 cm vertically-placed energy-harvesting clear glass panel of transparency exceeding 60%, invisible solar energy attenuation greater than 90% and electrical power output near 30 Wp/m2 mainly generated by infrared (IR) and UV radiations. These results open the way for the realization of large-area visibly-transparent energy-harvesting clear glass windows for BIPV systems. PMID:25321890
Photonic microstructures for energy-generating clear glass and net-zero energy buildings
Vasiliev, Mikhail; Alghamedi, Ramzy; Nur-E-Alam, Mohammad; Alameh, Kamal
2016-01-01
Transparent energy-harvesting windows are emerging as practical building-integrated photovoltaics (BIPV), capable of generating electricity while simultaneously reducing heating and cooling demands. By incorporating spectrally-selective diffraction gratings as light deflecting structures of high visible transparency into lamination interlayers and using improved spectrally-selective thin-film coatings, most of the visible solar radiation can be transmitted through the glass windows with minimum attenuation. At the same time, the ultraviolet (UV) and a part of incident solar infrared (IR) radiation energy are converted and/or deflected geometrically towards the panel edge for collection by CuInSe2 solar cells. Experimental results show power conversion efficiencies in excess of 3.04% in 10 cm × 10 cm vertically-placed clear glass panels facing direct sunlight, and up to 2.08% in 50 cm × 50 cm installation-ready framed window systems. These results confirm the emergence of a new class of solar window system ready for industrial application. PMID:27550827
Beta- and gamma-dose measurements of the Godiva IV critical assembly.
Hankins, D E
1984-03-01
To aid in the re-evaluation of an exposure that occurred in 1963, information was required on the response of film badges to the beta- and gamma-ray doses from a critical assembly. Of particular interest was the beta spectra from the assembly. The techniques used and the results obtained in this study are of interest to health physicists at facilities where exposures to betas occur. The dose rates from the Los Alamos National Laboratory Godiva IV Critical Assembly were measured at numerous distances from the assembly four and 12 days following a burst. Information was obtained on the beta-particle spectra using absorption curve studies. The beta/gamma dose-rate ratio as a function of distance from the assembly was determined. Shielding provided by various metals, gloves and clothing was measured. The beta- and gamma-ray doses measured were compared with a film packet used in the past at the Nevada Test Site with two types of current TLD personnel badges. Measurements made with a commercial thin-window ion chamber instrument are compared with the dose rates obtained using other dosimeters.
Design Study of an X-ray Crystal Spectrometer for the HANBIT Mirror Machine
NASA Astrophysics Data System (ADS)
Lee, S. G.; Hwang, S. M.; Bitter, M. L.
1997-11-01
X-ray crystal spectroscopy is expected to play a major role for the diagnostics of the reactor-like plasmas produced in future large tokamaks, such as KSTAR and ITER. However, it is also desirable to extend the observable spectral range to longer wavelengths (7-15 dotA), which is of interest for the diagnostics of plasmas with much lower electron densities (10^11-10^12 cm-3) and electron temperatures (100 - 200 eV) in other magnetic-confinement experiments, such as the HANBIT mirror machine. The construction of crystal spectrometers for this wavelength range and these plasma conditions is challenging because of the low X-ray emissivity and the fact that the low-energy X-rays are strongly attenuated by even very thin foils or windows. New types of detectors other than the presently used multi-wire proportional counters are therefore needed to obtain a high detection efficiency. In this paper, we present a design study for a vacuum spectrometer with a CCD array detector and detailed estimates of the instrument performance for the observation of spectra from O, Ne and Al ions.
2014-02-06
ISS038-E-042125 (6 Feb. 2014) --- A fresh apple floating freely near a window in the Cupola of the International Space Station is featured in this image photographed by an Expedition 38 crew member. The bright sun and the thin line of Earth's atmosphere provide the backdrop for the scene.
NASA Astrophysics Data System (ADS)
Naghavi, Negar; Hildebrandt, Thibaud; Bouttemy, Muriel; Etcheberry, Arnaud; Lincot, Daniel
2016-02-01
The highest and most reproducible (Cu(In,Ga)Se2 (CIGSe) based solar-cell efficiencies are obtained by use of a very thin n-type CdS layer deposited by chemical bath deposition (CBD). However because of both Cadmium's adverse environmental impact and the narrow bandgap of CdS (2.4-2.5 eV) one of the major objectives in the field of CIGSe technology remains the development and implementation in the production line of Cd-free buffer layers. The CBDZn( S,O) remains one the most studied buffer layer for replacing the CdS in Cu(In,Ga)Se2-based solar cells and has already demonstrated its potential to lead to high-efficiency solar cells up to 22.3%. However one of the key issue to implement a CBD-Zn(S,O) process in a CIGSe production line is the cells stability, which depends both on the deposition conditions of CBD-Zn(S,O) and on a good band alignment between CIGSe/Zn(S,O)/windows layers. The most common window layers applied in CIGSe solar cells consist of two layers : a thin (50-100 nm) and highly resistive i-ZnO layer deposited by magnetron sputtering and a transparent conducting 300-500 nm ZnO:Al layer. In the case of CBD-Zn(S,O) buffer layer, the nature and deposition conditions of both Zn(S,O) and the undoped window layer can strongly influence the performance and stability of cells. The present contribution will be specially focused on the effect of condition growth of CBD-Zn(S,O) buffer layers and the impact of the composition and deposition conditions of the undoped window layers such as ZnxMgyO or ZnxSnyO on the stability and performance of these solar cells.
Sakao, Yukinori; Kuroda, Hiroaki; Mun, Mingyon; Uehara, Hirofumi; Motoi, Noriko; Ishikawa, Yuichi; Nakagawa, Ken; Okumura, Sakae
2014-01-01
Background We aimed to clarify that the size of the lung adenocarcinoma evaluated using mediastinal window on computed tomography is an important and useful modality for predicting invasiveness, lymph node metastasis and prognosis in small adenocarcinoma. Methods We evaluated 176 patients with small lung adenocarcinomas (diameter, 1–3 cm) who underwent standard surgical resection. Tumours were examined using computed tomography with thin section conditions (1.25 mm thick on high-resolution computed tomography) with tumour dimensions evaluated under two settings: lung window and mediastinal window. We also determined the patient age, gender, preoperative nodal status, tumour size, tumour disappearance ratio, preoperative serum carcinoembryonic antigen levels and pathological status (lymphatic vessel, vascular vessel or pleural invasion). Recurrence-free survival was used for prognosis. Results Lung window, mediastinal window, tumour disappearance ratio and preoperative nodal status were significant predictive factors for recurrence-free survival in univariate analyses. Areas under the receiver operator curves for recurrence were 0.76, 0.73 and 0.65 for mediastinal window, tumour disappearance ratio and lung window, respectively. Lung window, mediastinal window, tumour disappearance ratio, preoperative serum carcinoembryonic antigen levels and preoperative nodal status were significant predictive factors for lymph node metastasis in univariate analyses; areas under the receiver operator curves were 0.61, 0.76, 0.72 and 0.66, for lung window, mediastinal window, tumour disappearance ratio and preoperative serum carcinoembryonic antigen levels, respectively. Lung window, mediastinal window, tumour disappearance ratio, preoperative serum carcinoembryonic antigen levels and preoperative nodal status were significant factors for lymphatic vessel, vascular vessel or pleural invasion in univariate analyses; areas under the receiver operator curves were 0.60, 0.81, 0.81 and 0.65 for lung window, mediastinal window, tumour disappearance ratio and preoperative serum carcinoembryonic antigen levels, respectively. Conclusions According to the univariate analyses including a logistic regression and ROCs performed for variables with p-values of <0.05 on univariate analyses, our results suggest that measuring tumour size using mediastinal window on high-resolution computed tomography is a simple and useful preoperative prognosis modality in small adenocarcinoma. PMID:25365326
Optical filters for wavelength selection in fluorescence instrumentation.
Erdogan, Turan
2011-04-01
Fluorescence imaging and analysis techniques have become ubiquitous in life science research, and they are poised to play an equally vital role in in vitro diagnostics (IVD) in the future. Optical filters are crucial for nearly all fluorescence microscopes and instruments, not only to provide the obvious function of spectral control, but also to ensure the highest possible detection sensitivity and imaging resolution. Filters make it possible for the sample to "see" light within only the absorption band, and the detector to "see" light within only the emission band. Without filters, the detector would not be able to distinguish the desired fluorescence from scattered excitation light and autofluorescence from the sample, substrate, and other optics in the system. Today the vast majority of fluorescence instruments, including the widely popular fluorescence microscope, use thin-film interference filters to control the spectra of the excitation and emission light. Hence, this unit emphasizes thin-film filters. After briefly introducing different types of thin-film filters and how they are made, the unit describes in detail different optical filter configurations in fluorescence instruments, including both single-color and multicolor imaging systems. Several key properties of thin-film filters, which can significantly affect optical system performance, are then described. In the final section, tunable optical filters are also addressed in a relative comparison.
Tritium autoradiography with thinned and back-side illuminated monolithic active pixel sensor device
NASA Astrophysics Data System (ADS)
Deptuch, G.
2005-05-01
The first autoradiographic results of the tritium ( 3H) marked source obtained with monolithic active pixel sensors are presented. The detector is a high-resolution, back-side illuminated imager, developed within the SUCIMA collaboration for low-energy (<30 keV) electrons detection. The sensitivity to these energies is obtained by thinning the detector, originally fabricated in the form of a standard VLSI chip, down to the thickness of the epitaxial layer. The detector used is the 1×10 6 pixel, thinned MIMOSA V chip. The low noise performance and thin (˜160 nm) entrance window provide the sensitivity of the device to energies as low as ˜4 keV. A polymer tritium source was parked directly atop the detector in open-air conditions. A real-time image of the source was obtained.
Simulated Thin-Film Growth and Imaging
NASA Astrophysics Data System (ADS)
Schillaci, Michael
2001-06-01
Thin-films have become the cornerstone of the electronics, telecommunications, and broadband markets. A list of potential products includes: computer boards and chips, satellites, cell phones, fuel cells, superconductors, flat panel displays, optical waveguides, building and automotive windows, food and beverage plastic containers, metal foils, pipe plating, vision ware, manufacturing equipment and turbine engines. For all of these reasons a basic understanding of the physical processes involved in both growing and imaging thin-films can provide a wonderful research project for advanced undergraduate and first-year graduate students. After producing rudimentary two- and three-dimensional thin-film models incorporating ballsitic deposition and nearest neighbor Coulomb-type interactions, the QM tunneling equations are used to produce simulated scanning tunneling microscope (SSTM) images of the films. A discussion of computational platforms, languages, and software packages that may be used to accomplish similar results is also given.
Enhanced optical band-gap of ZnO thin films by sol-gel technique
DOE Office of Scientific and Technical Information (OSTI.GOV)
Raghu, P., E-mail: dpr3270@gmail.com; Naveen, C. S.; Shailaja, J.
2016-05-06
Transparent ZnO thin films were prepared using different molar concentration (0.1 M, 0.2 M & 0.8 M) of zinc acetate on soda lime glass substrates by the sol-gel spin coating technique. The optical properties revealed that the transmittance found to decrease with increase in molar concentration. Absorption edge showed that the higher concentration film has increasingly red shifted. An increased band gap energy of the thin films was found to be direct allowed transition of ∼3.9 eV exhibiting their relevance for photovoltaic applications. The extinction coefficient analysis revealed maximum transmittance with negligible absorption coefficient in the respective wavelengths. The resultsmore » of ZnO thin film prepared by sol-gel technique reveal its suitability for optoelectronics and as a window layer in solar cell applications.« less
Controller for the Electronically Scanned Thinned Array Radiometer (ESTAR) instrument
NASA Technical Reports Server (NTRS)
Zomberg, Brian G.; Chren, William A., Jr.
1994-01-01
A prototype controller for the ESTAR (electronically scanned thinned array radiometer) instrument has been designed and tested. It manages the operation of the digital data subsystem (DDS) and its communication with the Small Explorer data system (SEDS). Among the data processing tasks that it coordinates are FEM data acquisition, noise removal, phase alignment and correlation. Its control functions include instrument calibration and testing of two critical subsystems, the output data formatter and Walsh function generator. It is implemented in a Xilinx XC3064PC84-100 field programmable gate array (FPGA) and has a maximum clocking frequency of 10 MHz.
Electrostatic analyzer measurements of ionospheric thermal ion populations
Fernandes, P. A.; Lynch, K. A.
2016-07-09
Here, we define the observational parameter regime necessary for observing low-altitude ionospheric origins of high-latitude ion upflow/outflow. We present measurement challenges and identify a new analysis technique which mitigates these impediments. To probe the initiation of auroral ion upflow, it is necessary to examine the thermal ion population at 200-350 km, where typical thermal energies are tenths of eV. Interpretation of the thermal ion distribution function measurement requires removal of payload sheath and ram effects. We use a 3-D Maxwellian model to quantify how observed ionospheric parameters such as density, temperature, and flows affect in situ measurements of the thermalmore » ion distribution function. We define the viable acceptance window of a typical top-hat electrostatic analyzer in this regime and show that the instrument's energy resolution prohibits it from directly observing the shape of the particle spectra. To extract detailed information about measured particle population, we define two intermediate parameters from the measured distribution function, then use a Maxwellian model to replicate possible measured parameters for comparison to the data. Liouville's theorem and the thin-sheath approximation allow us to couple the measured and modeled intermediate parameters such that measurements inside the sheath provide information about plasma outside the sheath. We apply this technique to sounding rocket data to show that careful windowing of the data and Maxwellian models allows for extraction of the best choice of geophysical parameters. More widespread use of this analysis technique will help our community expand its observational database of the seed regions of ionospheric outflows.« less
M.J. Wald; J.M. Considine; K.T. Turner
2013-01-01
Instrumented indentation is a technique that can be used to measure the elastic properties of soft thin films supported on stiffer substrates, including polymer films, cellulosic sheets, and thin layers of biological materials. When measuring thin film properties using indentation, the effect of the substrate must be considered. Most existing models for determining the...
Mascarenhas, Nicholas; Marleau, Peter; Brennan, James S.; Krenz, Kevin D.
2010-06-22
An instrument that will directly image the fast fission neutrons from a special nuclear material source has been described. This instrument can improve the signal to background compared to non imaging neutron detection techniques by a factor given by ratio of the angular resolution window to 4.pi.. In addition to being a neutron imager, this instrument will also be an excellent neutron spectrometer, and will be able to differentiate between different types of neutron sources (e.g. fission, alpha-n, cosmic ray, and D-D or D-T fusion). Moreover, the instrument is able to pinpoint the source location.
Konishi, Yuki; Hayashi, Hiroaki; Takegami, Kazuki; Fukuda, Ikuma; Ueno, Junji
2014-01-01
A cloud chamber is a detector that can visualize the tracks of charged particles. Hayashi, et al. suggested a visualization experiment in which X-rays generated by diagnostic X-ray equipment were directed into a cloud chamber; however, there was a problem in that the wall of the cloud chamber scattered the incoming X-rays. In this study, we developed a new cloud chamber with entrance windows. Because these windows are made of thin film, we were able to direct the X-rays through them without contamination by scattered X-rays from the cloud chamber wall. We have newly proposed an experiment in which beta-particles emitted from radioisotopes are directed into a cloud chamber. We place shielding material in the cloud chamber and visualize the various shielding effects seen with the material positioned in different ways. During the experiment, electrons scattered in the air were measured quantitatively using GM counters. We explained the physical phenomena in the cloud chamber using Monte Carlo simulation code EGS5. Because electrons follow a tortuous path in air, the shielding material must be placed appropriately to be able to effectively block their emissions. Visualization of the tracks of charged particles in this experiment proved effective for instructing not only trainee radiological technologists but also different types of healthcare professionals.
NASA Astrophysics Data System (ADS)
Zhao, Jin Shi; Lee, Hyun Ju; Sim, Joon Seop; Lee, Keun; Hwang, Cheol Seong
2006-04-01
Ferroelectric reliability of Pb(Zr0.15Ti0.85)O3 films grown by metal-organic chemical vapor deposition at 570°C on an Ir electrode in the self-regulation process window [constant Pb concentration irrespective of the precursor input ratio (Pb /(Zr+Ti), PIR)] was studied. Although the Pb composition and crystallinity of the films grown under different PIR were almost identical, the film grown under a PIR which was near the center of the process window showed the best ferroelectric performance. X-ray photoelectron spectroscopy showed that the films grown at lower and higher PIR have residual ZrO2 and metallic Pb, respectively, which resulted in reduced remanent polarization and reliability.
Tactical/Combat Engines Cetane Window Evaluation
2013-01-31
non-instrumented injector . The leaky instrumented injector was showing some of the combustion characteristics of the diesel fuel and it was...Instrumented HEUI-B Injector -10 0 10 20 30 40 50 60 70 80 90 100 -30 -20 -10 0 10 20 30 40 50 60 J/ CA D CAD HRR Comparison of Different Injectors Diesel ...SUPPLEMENTARY NOTES 14. ABSTRACT The European Stationary Cycle 13 Mode test was performed on a turbocharged inline 6-cylinder diesel engine and a
1979-01-22
window locations at which interferometric measurements are gathered while the window is in motion. Figure 3 is an optical schematic and Figure 4 shows...imposed in system opera- tion although they have not been subjected to the interferometric analysis as presented here. Evaluation of Mirror #2 As...aberrations present. Introduction We present a technique for evaluating optical aberrations from interferometric data; a measured wavefront is
Self Validation of Radiance Measurements from the CERES (TRMM)Instrument
NASA Technical Reports Server (NTRS)
Paden, Jack; Pandey, Dhirendra K.; Lee, Robert B., III; Priestley, Kory J.
1999-01-01
Eight continuous months of earth-nadir-viewing radiance measurements from the 3-channel Tropical Rainfall Measuring Mission (TRMM,) Clouds and the Earth's Radiant Energy System (CERES) scanning radiometric measurement instrument, have been analyzed. While previous remote sensing satellites, such as the Earth Radiation Budget Experiment (ERBE) covered all subsets of the broadband radiance spectrum (total, longwave and shortwave.) CERES has two subset channels (window and shortwave) which do not give continuous frequency coverage over the total band. Previous experience with ERBE indicated the need for us to model the equivalent daytime longwave radiance using a window channel regression, which will allow us to validate the performance of the instrument using a three-channel inter-comparison. Limiting our consideration to the fixed azimuth plane, cross-track, scanning mode (FAPS), each nadir-viewing measurement was averaged into three subjective categories called daytime, nighttime, and twilight. Daytime was defined as any measurement taken when the solar zenith angle (SZA) was less than 90 ; nighttime was taken to be any measurement where the SZA was greater than 117 ; and twilight was everything else. Our analysis indicates that there are only two distinct categories of nadir-view data; daytime, and non-daytime (i.e., the union of the nighttime and twilight sets); and that the CERES longwave radiance is predictable to an accuracy of 1%, based on the SZA, and window channel measurements.
Time-Resolved Data Acquisition for In Situ Subsurface Planetary Geochemistry
NASA Technical Reports Server (NTRS)
Bodnarik, Julia Gates; Burger, Dan M.; Burger, Arnold; Evans, Larry G.; Parsons, Ann M.; Starr, Richard D.; Stassun, Keivan G.
2012-01-01
The current gamma-ray/neutron instrumentation development effort at NASA Goddard Space Flight Center aims to extend the use of active pulsed neutron interrogation techniques to probe the subsurface geochemistry of planetary bodies in situ. All previous NASA planetary science missions, that used neutron and/or gamma-ray spectroscopy instruments, have relied on a constant neutron source produced from galactic cosmic rays. One of the distinguishing features of this effort is the inclusion of a high intensity 14.1 MeV pulsed neutron generator synchronized with a custom data acquisition system to time each event relative to the pulse. With usually only one opportunity to collect data, it is difficult to set a priori time-gating windows to obtain the best possible results. Acquiring time-tagged, event-by-event data from nuclear induced reactions provides raw data sets containing channel/energy, and event time for each gamma ray or neutron detected. The resulting data set can be plotted as a function of time or energy using optimized analysis windows after the data are acquired. Time windows can now be chosen to produce energy spectra that yield the most statistically significant and accurate elemental composition results that can be derived from the complete data set. The advantages of post-processing gamma-ray time-tagged event-by-event data in experimental tests using our prototype instrument will be demonstrated.
Time-resolved Neutron-gamma-ray Data Acquisition for in Situ Subsurface Planetary Geochemistry
NASA Technical Reports Server (NTRS)
Bodnarik, Julie G.; Burger, Dan Michael; Burger, A.; Evans, L. G.; Parsons, A. M.; Schweitzer, J. S.; Starr R. D.; Stassun, K. G.
2013-01-01
The current gamma-ray/neutron instrumentation development effort at NASA Goddard Space Flight Center aims to extend the use of active pulsed neutron interrogation techniques to probe the subsurface elemental composition of planetary bodies in situ. Previous NASA planetary science missions, that used neutron and/or gamma-ray spectroscopy instruments, have relied on neutrons produced from galactic cosmic rays. One of the distinguishing features of this effort is the inclusion of a high intensity 14.1 MeV pulsed neutron generator synchronized with a custom data acquisition system to time each event relative to the pulse. With usually only one opportunity to collect data, it is difficult to set a priori time-gating windows to obtain the best possible results. Acquiring time-tagged, event-by-event data from nuclear induced reactions provides raw data sets containing channel/energy, and event time for each gamma ray or neutron detected. The resulting data set can be plotted as a function of time or energy using optimized analysis windows after the data are acquired. Time windows can now be chosen to produce energy spectra that yield the most statistically significant and accurate elemental composition results that can be derived from the complete data set. The advantages of post-processing gamma-ray time-tagged event-by-event data in experimental tests using our prototype instrument will be demonstrated.
NASA Technical Reports Server (NTRS)
Loeb, N. G.; Priestley, K. J.; Kratz, D. P.; Geier, E. B.; Green, R. N.; Wielicki, B. A.; Hinton, P. OR.; Nolan, S. K.
2001-01-01
A new method for determining unfiltered shortwave (SW), longwave (LW) and window (W) radiances from filtered radiances measured by the Clouds and the Earth's Radiant Energy System (CERES) satellite instrument is presented. The method uses theoretically derived regression coefficients between filtered and unfiltered radiances that are a function of viewing geometry, geotype and whether or not cloud is present. Relative errors in insta.ntaneous unfiltered radiances from this method are generally well below 1% for SW radiances (approx. 0.4% 1(sigma) or approx.l W/sq m equivalent flux), < 0.2% for LW radiances (approx. 0.1% 1(sigma) or approx.0.3 W/sq m equivalent flux) and < 0.2% (approx. 0.1% 1(sigma) for window channel radiances.
Astronomy from the Moon: A New Frontier for 21st Century Astrophysics
NASA Astrophysics Data System (ADS)
Durst, Steve
2018-06-01
The International Lunar Observatory Association of Hawai'i USA continues into its second decade with research and development of South Pole instruments for astronomy, observation and communication from the Moon. Since the pioneering first astronomy observations from the Moon by Apollo 16 Commander John Young (an ILOA founding-emeritus director until his recent passing), with China Lunar Ultraviolet Telescope LUT operations and current American and European considerations for far-side radio telescopes, today's climate is most promising for a diversity of lunar-based astronomy locations, instruments and technologies. ILOA is aiming to advance this frontier through its Galaxy First Light Imaging program, being developed through contracts with Moon Express and Canadensys Aerospace Corp.A wide variety of extreme and unique lunar conditions enable many astronomy activities and installations, on the Moon's near-side, far-side, north pole, and south pole: The extremely thin lunar exosphere favors observations in millimeter / submillimeter to optical, UV, X-ray, and gamma-ray wavelengths; the highly stable platform that is the Moon provides for long-duration observations; ultra cold, shaded areas for cryogenic infrared instruments; far-side radio-quiet environment for radio telescopes and VLF astronomy; 1/6-Earth gravity for production and utilization of new, very lightweight materials and instruments, including large refractors, 100-m class liquid mirror telescopes, and possibly 1,000-m class radio telescopes and interferometer antenna arrays vastly larger than Atacama LMA; North and especially South Pole sites, with high peaks and long solar power windows, offer perhaps the widest variety of lunar conditions and opportunities for astronomical innovation on the Moon: a veritable "condominium of observatories".21st century astrophysics seems likely to find Luna a very busy and productive new frontier, as American Astronomical Society and IAU members will validate, with astronomers providing rationale and direction for lunar outpost build-out, while offering Galaxy / Cosmos perspective on the human advance towards a multi world civilization.
NASA Astrophysics Data System (ADS)
Pathak, Trilok Kumar; Kumar, Vinod; Swart, H. C.; Purohit, L. P.
2016-03-01
Undoped, doped and codoped ZnO thin films were synthesized on glass substrates using a spin coating technique. Zinc acetate dihydrate, ammonium acetate and aluminum nitrate were used as precursor for zinc, nitrogen and aluminum, respectively. X-ray diffraction shows that the thin films have a hexagonal wurtzite structure for the undoped, doped and co-doped ZnO. The transmittance of the films was above 80% and the band gap of the film varied from 3.20 eV to 3.24 eV for undoped and doped ZnO. An energy band diagram to describe the photoluminescence from the thin films was also constructed. This diagram includes the various defect levels and possible quasi-Fermi levels. A minimum resistivity of 0.0834 Ω-cm was obtained for the N and Al codoped ZnO thin films with p-type carrier conductivity. These ZnO films can be used as a window layer in solar cells and in UV lasers.
Defect Depth Measurement Using White Light Interferometry
NASA Technical Reports Server (NTRS)
Parker, Don; Starr, Stan
2009-01-01
The objectives of the White Light Interferometry project are the following: (1) Demonstrate a small hand-held instrument capable of performing inspections of identified defects on Orbiter outer pane window surfaces. (2) Build and field-test a prototype device using miniaturized optical components. (3) Modify the instrument based on field testing and begin the conversion of the unit to become a certified shop-aid.
NASA Astrophysics Data System (ADS)
Morata, Oscar; Huang, Ted
2017-06-01
ALMA's Band 1 receivers will open up the 7 mm window to the 66 antennas on Chajnantor Plateau. Oscar Morata and Ted Huang relate the expected delivery schedule and science goals for these instruments.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Va'Vra, J.
The publication of the ICFA Instrumentation Bulletin is an activity of the Panel on Future Innovation and Development of ICFA (International Committee for Future Accelerators). The Bulletin reports on research and progress in the field of instrumentation with emphasis on application in the field of high-energy physics. It encourages issues of generic instrumentation. This volume contains the following articles: (1) ''Gaseous Micropattern Detectors: High-Energy Physics and Beyond''; (2) ''DIRC Dreams Redux: Research Directions for the Next Generation of Internally Reflected Imaging Counters''; and (3) ''Corrosion of Glass Windows in DIRC PMTs''.
Ultra-thin plasma panel radiation detector
DOE Office of Scientific and Technical Information (OSTI.GOV)
Friedman, Peter S.
An ultra-thin radiation detector includes a radiation detector gas chamber having at least one ultra-thin chamber window and an ultra-thin first substrate contained within the gas chamber. The detector further includes a second substrate generally parallel to and coupled to the first substrate and defining a gas gap between the first substrate and the second substrate. The detector further includes a discharge gas between the substrates and contained within the gas chamber, where the discharge gas is free to circulate within the gas chamber and between the first and second substrates at a given gas pressure. The detector further includesmore » a first electrode coupled to one of the substrates and a second electrode electrically coupled to the first electrode. The detector further includes a first discharge event detector coupled to at least one of the electrodes for detecting a gas discharge counting event in the electrode.« less
NASA Technical Reports Server (NTRS)
Spencer, Dwight C.
1996-01-01
Hoover et. al. built and tested two imaging Schwarzschild multilayer microscopes. These instruments were constructed as prototypes for the "Water Window Imaging X-Ray Microscope," which is a doubly reflecting, multilayer x-ray microscope configured to operate within the "water window." The "water window" is the narrow region of the x-ray spectrum between the K absorption edges of oxygen (lamda = 23.3 Angstroms) and of carbon (lamda = 43.62 Angstroms), where water is relatively highly transmissive and carbon is highly absorptive. This property of these materials, thus permits the use of high resolution multilayer x-ray microscopes for producing high contrast images of carbon-based structures within the aqueous physiological environments of living cells. We report the design, fabrication and testing of multilayer optics that operate in this regime.
2003-09-08
KENNEDY SPACE CENTER, FLA. - The Window Observational Research Facility (WORF), seen in the Space Station Processing Facility, was designed and built by the Boeing Co. at NASA’s Marshall Space Flight Center in Huntsville, Ala. WORF will be delivered to the International Space Station and placed in the rack position in front of the Destiny lab window, providing locations for attaching cameras, multi-spectral scanners and other instruments. WORF will support a variety of scientific and commercial experiments in areas of Earth systems and processes, global ecological changes in Earth’s biosphere, lithosphere, hydrosphere and climate system, Earth resources, natural hazards, and education. After installation, it will become a permanent focal point for Earth Science research aboard the space station.
2003-09-08
KENNEDY SPACE CENTER, FLA. - Workers in the Space Station Processing Facility check out the Window Observational Research Facility (WORF), designed and built by the Boeing Co. at NASA’s Marshall Space Flight Center in Huntsville, Ala. WORF will be delivered to the International Space Station and placed in the rack position in front of the Destiny lab window, providing locations for attaching cameras, multi-spectral scanners and other instruments. WORF will support a variety of scientific and commercial experiments in areas of Earth systems and processes, global ecological changes in Earth’s biosphere, lithosphere, hydrosphere and climate system, Earth resources, natural hazards, and education. After installation, it will become a permanent focal point for Earth Science research aboard the space station.
Novel Drift Structures for Silicon and Compound Semiconductor X-Ray and Gamma-Ray Detectors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bradley E. Patt; Jan S. Iwanczyk
Recently developed silicon- and compound-semiconductor-based drift detector structures have produced excellent performance for charged particles, X rays, and gamma rays and for low-signal visible light detection. The silicon drift detector (SDD) structures that we discuss relate to direct X-ray detectors and scintillation photon detectors coupled with scintillators for gamma rays. Recent designs include several novel features that ensure very low dark current (both bulk silicon dark current and surface dark current) and hence low noise. In addition, application of thin window technology ensures a very high quantum efficiency entrance window on the drift photodetector.
Han, Yimo; Nguyen, Kayla X; Ogawa, Yui; Park, Jiwoong; Muller, David A
2016-12-14
Scanning electron microscopes (SEMs) require a high vacuum environment to generate and shape an electron beam for imaging; however, the vacuum conditions greatly limit the nature of specimens that can be examined. From a purely scattering physics perspective, it is not necessary to place the specimen inside the vacuum chamber-the mean free paths (MFPs) for electron scattering in air at typical SEM beam voltages are 50-100 μm. This is the idea behind the airSEM, which removes the specimen vacuum chamber from the SEM and places the sample in air. The thickness of the gas layer is less than a MFP from an electron-transparent window to preserve the shape and resolution of the incident beam, resulting in comparable imaging quality to an all-vacuum SEM. Present silicon nitride windows scatter far more strongly than the air gap and are currently the contrast and resolution limiting factor in the airSEM. Graphene windows have been used previously to wrap or seal samples in vacuum for imaging. Here we demonstrate the use of a robust bilayer graphene window for sealing the electron optics from the room environment, providing an electron transparent window with only a 2% drop in contrast. There is a 5-fold-increase in signal/noise ratio for imaging compared to multi-MFP-thick silicon nitride windows, enabling high contrast in backscattered, transmission, and surface imaging modes for the new airSEM geometry.
Thermal Stress in HFEF Hot Cell Windows Due to an In-Cell Metal Fire
Solbrig, Charles W.; Warmann, Stephen A.
2016-01-01
This work investigates an accident during the pyrochemical extraction of Uranium and Plutonium from PWR spent fuel in an argon atmosphere hot cell. In the accident, the heavy metals (U and Pu) being extracted are accidentally exposed to air from a leaky instrument penetration which goes through the cell walls. The extracted pin size pieces of U and Pu metal readily burn when exposed to air. Technicians perform the electrochemical extraction using manipulators through a 4 foot thick hot cell concrete wall which protects them from the radioactivity of the spent fuel. Four foot thick windows placed in the wallmore » allow the technicians to visually control the manipulators. These windows would be exposed to the heat of the metal fire. As a result, this analysis determines if the thermal stress caused by the fire would crack the windows and if the heat would degrade the window seals allowing radioactivity to escape from the cell.« less
Thermal Stress in HFEF Hot Cell Windows Due to an In-Cell Metal Fire
DOE Office of Scientific and Technical Information (OSTI.GOV)
Solbrig, Charles W.; Warmann, Stephen A.
This work investigates an accident during the pyrochemical extraction of Uranium and Plutonium from PWR spent fuel in an argon atmosphere hot cell. In the accident, the heavy metals (U and Pu) being extracted are accidentally exposed to air from a leaky instrument penetration which goes through the cell walls. The extracted pin size pieces of U and Pu metal readily burn when exposed to air. Technicians perform the electrochemical extraction using manipulators through a 4 foot thick hot cell concrete wall which protects them from the radioactivity of the spent fuel. Four foot thick windows placed in the wallmore » allow the technicians to visually control the manipulators. These windows would be exposed to the heat of the metal fire. As a result, this analysis determines if the thermal stress caused by the fire would crack the windows and if the heat would degrade the window seals allowing radioactivity to escape from the cell.« less
Planck 2013 results. VII. HFI time response and beams
NASA Astrophysics Data System (ADS)
Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Armitage-Caplan, C.; Arnaud, M.; Ashdown, M.; Atrio-Barandela, F.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bobin, J.; Bock, J. J.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Bowyer, J. W.; Bridges, M.; Bucher, M.; Burigana, C.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chary, R.-R.; Chiang, H. C.; Chiang, L.-Y.; Christensen, P. R.; Church, S.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Delouis, J.-M.; Désert, F.-X.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Dunkley, J.; Dupac, X.; Efstathiou, G.; Enßlin, T. A.; Eriksen, H. K.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Galeotta, S.; Ganga, K.; Giard, M.; Giraud-Héraud, Y.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J. E.; Haissinski, J.; Hansen, F. K.; Hanson, D.; Harrison, D.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hou, Z.; Hovest, W.; Huffenberger, K. M.; Jaffe, A. H.; Jaffe, T. R.; Jones, W. C.; Juvela, M.; Keihänen, E.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Knox, L.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lamarre, J.-M.; Lasenby, A.; Laureijs, R. J.; Lawrence, C. R.; Leonardi, R.; Leroy, C.; Lesgourgues, J.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Macías-Pérez, J. F.; MacTavish, C. J.; Maffei, B.; Mandolesi, N.; Maris, M.; Marshall, D. J.; Martin, P. G.; Martínez-González, E.; Masi, S.; Massardi, M.; Matarrese, S.; Matsumura, T.; Matthai, F.; Mazzotta, P.; McGehee, P.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Osborne, S.; Oxborrow, C. A.; Paci, F.; Pagano, L.; Pajot, F.; Paoletti, D.; Pasian, F.; Patanchon, G.; Perdereau, O.; Perotto, L.; Perrotta, F.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polegre, A. M.; Polenta, G.; Ponthieu, N.; Popa, L.; Poutanen, T.; Pratt, G. W.; Prézeau, G.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reinecke, M.; Remazeilles, M.; Renault, C.; Ricciardi, S.; Riller, T.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Roudier, G.; Rowan-Robinson, M.; Rusholme, B.; Sandri, M.; Santos, D.; Sauvé, A.; Savini, G.; Scott, D.; Shellard, E. P. S.; Spencer, L. D.; Starck, J.-L.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sureau, F.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Tavagnacco, D.; Terenzi, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Umana, G.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Vittorio, N.; Wade, L. A.; Wandelt, B. D.; Yvon, D.; Zacchei, A.; Zonca, A.
2014-11-01
This paper characterizes the effective beams, the effective beam window functions and the associated errors for the Planck High Frequency Instrument (HFI) detectors. The effective beam is theangular response including the effect of the optics, detectors, data processing and the scan strategy. The window function is the representation of this beam in the harmonic domain which is required to recover an unbiased measurement of the cosmic microwave background angular power spectrum. The HFI is a scanning instrument and its effective beams are the convolution of: a) the optical response of the telescope and feeds; b) the processing of the time-ordered data and deconvolution of the bolometric and electronic transfer function; and c) the merging of several surveys to produce maps. The time response transfer functions are measured using observations of Jupiter and Saturn and by minimizing survey difference residuals. The scanning beam is the post-deconvolution angular response of the instrument, and is characterized with observations of Mars. The main beam solid angles are determined to better than 0.5% at each HFI frequency band. Observations of Jupiter and Saturn limit near sidelobes (within 5°) to about 0.1% of the total solid angle. Time response residuals remain as long tails in the scanning beams, but contribute less than 0.1% of the total solid angle. The bias and uncertainty in the beam products are estimated using ensembles of simulated planet observations that include the impact of instrumental noise and known systematic effects. The correlation structure of these ensembles is well-described by five error eigenmodes that are sub-dominant to sample variance and instrumental noise in the harmonic domain. A suite of consistency tests provide confidence that the error model represents a sufficient description of the data. The total error in the effective beam window functions is below 1% at 100 GHz up to multipole ℓ ~ 1500, and below 0.5% at 143 and 217 GHz up to ℓ ~ 2000.
Thin-ice Arctic Acoustic Window (THAAW)
2014-09-30
NewYork), pp. 11–37. Mikhalevsky, P. N., Sagen, H., Worcester, P. F., Baggeroer, A. B., Orcutt, J. A., Moore, S. E., Lee, C. M., Vigness -Raposa, K. J...P. F., Baggeroer, A. B., Orcutt, J. A., Moore, S. E., Lee, C. M., Vigness -Raposa, K. J., Freitag, L., Arrott, M., Atakan, K., Beszczynska-Moeller, A
Silicon-tin oxynitride glassy composition and use as anode for lithium-ion battery
Neudecker, Bernd J.; Bates, John B.
2001-01-01
Disclosed are silicon-tin oxynitride glassy compositions which are especially useful in the construction of anode material for thin-film electrochemical devices including rechargeable lithium-ion batteries, electrochromic mirrors, electrochromic windows, and actuators. Additional applications of silicon-tin oxynitride glassy compositions include optical fibers and optical waveguides.
NASA Astrophysics Data System (ADS)
Döge, Stefan; Hingerl, Jürgen
2018-03-01
The improvement of the number of extractable ultracold neutrons (UCNs) from converters based on solid deuterium (sD2) crystals requires a good understanding of the UCN transport and how the crystal's morphology influences its transparency to the UCNs. Measurements of the UCN transmission through cryogenic liquids and solids of interest, such as hydrogen (H2) and deuterium (D2), require sample containers with thin, highly polished and optically transparent windows and a well defined sample thickness. One of the most difficult sealing problems is that of light gases like hydrogen and helium at low temperatures against high vacuum. Here we report on the design of a sample container with two 1 mm thin amorphous silica windows cold-welded to aluminum clamps using indium wire gaskets, in order to form a simple, reusable, and hydrogen-tight cryogenic seal. The container meets the above-mentioned requirements and withstands up to 2 bar hydrogen gas pressure against isolation vacuum in the range of 10-5 to 10-7 mbar at temperatures down to 4.5 K. Additionally, photographs of the crystallization process are shown and discussed.
Piracha, Afaq H; Rath, Patrik; Ganesan, Kumaravelu; Kühn, Stefan; Pernice, Wolfram H P; Prawer, Steven
2016-05-11
Diamond has emerged as a promising platform for nanophotonic, optical, and quantum technologies. High-quality, single crystalline substrates of acceptable size are a prerequisite to meet the demanding requirements on low-level impurities and low absorption loss when targeting large photonic circuits. Here, we describe a scalable fabrication method for single crystal diamond membrane windows that achieves three major goals with one fabrication method: providing high quality diamond, as confirmed by Raman spectroscopy; achieving homogeneously thin membranes, enabled by ion implantation; and providing compatibility with established planar fabrication via lithography and vertical etching. On such suspended diamond membranes we demonstrate a suite of photonic components as building blocks for nanophotonic circuits. Monolithic grating couplers are used to efficiently couple light between photonic circuits and optical fibers. In waveguide coupled optical ring resonators, we find loaded quality factors up to 66 000 at a wavelength of 1560 nm, corresponding to propagation loss below 7.2 dB/cm. Our approach holds promise for the scalable implementation of future diamond quantum photonic technologies and all-diamond photonic metrology tools.
Band gap engineering of hydrogenated amorphous carbon thin films for solar cell application
NASA Astrophysics Data System (ADS)
Dwivedi, Neeraj; Kumar, Sushil; Dayal, Saurabh; Rauthan, C. M. S.; Panwar, O. S.; Malik, Hitendra K.
2012-10-01
In this work, self bias variation, nitrogen introduction and oxygen plasma (OP) treatment approaches have been used for tailoring the band gap of hydrogenated amorphous carbon (a-C:H) thin films. The band gap of a-C:H and modified a- C:H films is varied in the range from 1.25 eV to 3.45 eV, which is found to be nearly equal to the full solar spectrum (1 eV- 3.5 eV). Hence, such a-C:H and modified a-C:H films are found to be potential candidate for the development of full spectrum solar cells. Besides this, computer aided simulation with considering variable band gap a-C:H and modified a- C:H films as window layer for amorphous silicon p-i-n solar cells is also performed by AFORS-HET software and maximum efficiency as ~14 % is realized. Since a-C:H is hard material, hence a-C:H and modified a-C:H films as window layer may avoid the use of additional hard and protective coating particularly in n-i-p configuration.
Variable transmittance electrochromic windows
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rauh, R.D.
1983-11-01
Electrochromic apertures based on RF sputtered thin films of WO3 are projected to have widely different sunlight attenuation properties when converted to MxWO3 (M H, Li, Na, Ag, etc.), depending on the initial preparation conditions. Amorphous WO3, prepared at low temperature, has a coloration spectrum centered in the visible, while high temperature crystalline WO3 attenuates infrared light most efficiently, but appears to become highly reflective at high values of x. The possibility therefore exists of producing variable light transmission apertures of the general form (a-MxWO3/FIC/c-WO3), where the FIC is an ion conducting thin film, such as LiAlF4 (for M Li).more » The attenuation of 90% of the solar spectrum requires an injected charge of 30 to 40 mcoul/sq cm in either amorphous or crystalline WO3, corresponding to 0.2 Whr/sq m per coloration cycle. In order to produce windows with very high solar transparency in the bleached form, new counter electrode materials must be found with complementary electrochromism to WO3.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Srinivasan, Arvind; Czapla, Braden; Narayanaswamy, Arvind, E-mail: arvind.narayanaswamy@columbia.edu
The complex refractive index of polydimethylsiloxane (PDMS) is determined in the wavelength range between 2.5 μm and 16.7 μm. The parameters of a Drude-Lorentz oscillator model (with 15 oscillators) are extracted from Fourier transform infrared spectroscopy reflectance measurements made on both bulk PDMS and thin films of PDMS deposited on the gold coated silicon substrates. It is shown that thin films of PDMS atop gold exhibit selective emission in the 8 μm to 13 μm atmospheric transmittance window, which demonstrates that PDMS, especially due to its ease of deposition, may be a viable material for passive radiative cooling applications.
Infrared Emissivity of Tin upon Release of a 25 GPa Shock into a LiF Window
DOE Office of Scientific and Technical Information (OSTI.GOV)
Turley, W. D., Holtkamp, D. B., Marshall, B. R., Stevens, G. D., Veeser, L. R.
We measured the emissivity of a tin sample at its interface with a lithium-fluoride window upon release of a 25 GPa shock wave from the tin into the window. Measurements were made over four wavelength bands between 1.2 and 5.4 μm. Thermal emission backgrounds from the tin, glue, and lithium fluoride were successfully removed from the reflectance signals. Emissivity changes for the sample, which was initially nearly specular, were small except for the longest wavelength band, where uncertainties were high because of poor signal-to-noise ratio at that wavelength. A thin glue layer, which bonds the sample to the window, wasmore » found to heat from reverberations of the shock wave between the tin and the lithium fluoride. At approximately 3.4 μm the thermal emission from the glue was large compared to the tin, allowing a good estimate of the glue temperature from the thermal radiance. The glue appears to remain slightly colder than the tin, thereby minimizing heat conduction into or out of the tin immediately after the shock passage.« less
2015-06-01
National Instruments. The National Instruments DAQ is a full-featured PC running Windows 7. The DAQ, electromagnetic transmitter , and batteries for the... electromagnetic induction Environet Environet, Inc. ESTCP Environmental Security Technology Certification Program ftp file transfer protocol FUDS formerly used...capabilities of a currently available advanced electromagnetic induction sensor developed specifically for discrimination on real sites under operational
NASA Technical Reports Server (NTRS)
Mookherji, T.
1976-01-01
Outgassing, deposition, and desorption kinetics of silicone compounds, are examined as examples of optical surface contaminants of spacecraft windows. Their behavior in a space environment after exposure to ultraviolet radiation is also examined. The use of internal reflection spectroscopy is shown to provide a viable means of real-time, in-situ identification of contaminants of orbiting spacecraft. The instrumental techniques are proposed as the basis of further investigations and the development of flight hardware.
Robust Control for the Mercury Laser Altimeter
NASA Technical Reports Server (NTRS)
Rosenberg, Jacob S.
2006-01-01
Mercury Laser Altimeter Science Algorithms is a software system for controlling the laser altimeter aboard the Messenger spacecraft, which is to enter into orbit about Mercury in 2011. The software will control the altimeter by dynamically modifying hardware inputs for gain, threshold, channel-disable flags, range-window start location, and range-window width, by using ranging information provided by the spacecraft and noise counts from instrument hardware. In addition, because of severe bandwidth restrictions, the software also selects returns for downlink.
Designing Light Beam Transmittance Measuring Tool Using a Laser Pointer
NASA Astrophysics Data System (ADS)
Nuroso, H.; Kurniawan, W.; Marwoto, P.
2016-08-01
A simple instrument used for measuring light beam transmittance percentage made of window film has been developed. The instrument uses a laser pointer of 405 nm and 650 nm ±10% as a light source. Its accuracy approaches 80%. Transmittance data was found by comparing the light beam before and after passing the window film. The light intensity measuring unit was deleted by splitting the light source into two beams through a beam splitter. The light beam was changed into resistance by a NORP12 LDR sensor designed at a circuit of voltage divider rule of Khirchoff's laws. This conversion system will produce light beam intensity received by the sensor to become an equal voltage. This voltage will, then, be presented on the computer screen in the form of a real time graph via a 2.0 USB data transfer.
WinTICS-24 --- A Telescope Control Interface for MS Windows
NASA Astrophysics Data System (ADS)
Hawkins, R. Lee
1995-12-01
WinTICS-24 is a telescope control system interface and observing assistant written in Visual Basic for MS Windows. It provides the ability to control a telescope and up to 3 other instruments via the serial ports on an IBM-PC compatible computer, all from one consistent user interface. In addition to telescope control, WinTICS contains an observing logbook, trouble log (which can automatically email its entries to a responsible person), lunar phase display, object database (which allows the observer to type in the name of an object and automatically slew to it), a time of minimum calculator for eclipsing binary stars, and an interface to the Guide CD-ROM for bringing up finder charts of the current telescope coordinates. Currently WinTICS supports control of DFM telescopes, but is easily adaptable to other telescopes and instrumentation.
Window Observational Rack Facility (WORF)
NASA Technical Reports Server (NTRS)
2002-01-01
Developed by Boeing, at the Marshall Space Flight Center (MSFC) Space Station Manufacturing building, the Window Observational Rack Facility (WORF) will help Space Station crews take some of the best photographs ever snapped from an orbiting spacecraft by eliminating glare and allowing researchers to control their cameras and other equipment from the ground. The WORF is designed to make the best possible use of the high-quality research window in the Space Station's U.S. Destiny laboratory module. Engineers at the MSFC proposed a derivative of the EXPRESS (Expedite the Processing of Experiments to the Space Station) Rack already used on the Space Station and were given the go-ahead. The EXPRESS rack can hold a wide variety of experiments and provide them with power, communications, data, cooling, fluids, and other utilities - all the things that Earth-observing experiment instruments would need. WORF will supply payloads with power, data, cooling, video downlink, and stable, standardized interfaces for mounting imaging instruments. Similar to specialized orbital observatories, the interior of the rack is sealed against light and coated with a special low-reflectant black paint, so payloads will be able to observe low-light-level subjects such as the faint glow of auroras. Cameras and remote sensing instruments in the WORF can be preprogrammed, controlled from the ground, or operated by a Station crewmember by using a flexible shroud designed to cinch tightly around the crewmember's waist. The WORF is scheduled to be launched aboard the STS-114 Space Shuttle mission in the year 2003.
Atmospheric Electron-induced X-Ray Spectrometer (AEXS) Instrument Development
NASA Technical Reports Server (NTRS)
Wilcox, J. Z.; Urgiles, E.; Toda, R.; George, T.; Crisp, J.
2005-01-01
Instrument Development: The membrane properties were investigated in detail due to its critical role. A series of experiments determined that our designed membranes have high electron transmission, yet are capable of isolating high vacuum, are able to withstand differential pressure in excess of one atmosphere, survive vibrational shocks of a magnitude to be expected during a planetary mission. Our initial work has been with a 10 keV source and a 200 nm thick Silicon Nitride (SiN) encapsulation membrane micro-fabricated within a Si support frame (1.5 mm x 1.5 mm window openings. Fig 2 compares the spectra taken with the 10 keV source with spectra taken within SEM. Introduction: This paper describes the progress in the development of the AEXS instrument in our laboratory at JPL. The AEXS is a novel miniature instrument[1-3] based on the excitation of characteristic X-Ray Fluorescence (XRF) and luminescence spectra using a focused electron beam, for non-destructive evaluation of surfaces of samples in planetary ambient atmosphere. In situ operation is obtained through the use of a thin electron transmissive membrane to isolate the vacuum within the AEXS electron source from the outside ambient atmosphere. The impinging electrons excite XRF spectra from the irradiated spots on samples in external atmosphere with high-to-medium (sub-mm to cm-scale) spatial resolution at Mars atmospheric pressure. The XRF spectra are analyzed using an energy-dispersive detector to determine surface elemental composition, or in the case of electron-induced luminescence to identify unusual formations on surface that cathodo-luminescence (CL). The AEXS system (Fig 1) consists of a high-energy (>10keV) electron gun encapsulated by the isolation membrane, an EDX detection and analyzer system to determine the elemental abundance, an optional CL detection system, and a high voltage power supply. The approach to demonstrating a proof of concept of the AEXS has been through 1) demonstrating the viability of micro-fabricated membranes, 2) assembling AEXS setups with increasingly integrated functional components, and 3) simulating the AEXS observational capabilities. This paper will focus on description of the development of the instrument.
Surface transmission enhancement of ZnS via continuous-wave laser microstructuring
NASA Astrophysics Data System (ADS)
Major, Kevin J.; Florea, Catalin M.; Poutous, Menelaos K.; Busse, Lynda E.; Sanghera, Jasbinder S.; Aggarwal, Ishwar D.
2014-03-01
Fresnel reflectivity at dielectric boundaries between optical components, lenses, and windows is a major issue for the optics community. The most common method to reduce the index mismatch and subsequent surface reflection is to apply a thin film or films of intermediate indices to the optical materials. More recently, surface texturing or roughening has been shown to approximate a stepwise refractive index thin-film structure, with a gradient index of refraction transition from the bulk material to the surrounding medium. Short-pulse laser ablation is a recently-utilized method to produce such random anti-reflective structured surfaces (rARSS). Typically, high-energy femtosecond pulsed lasers are focused on the surface of the desired optical material to produce periodic or quasi-periodic assemblies of nanostructures which provide reduced surface reflection. This technique is being explored to generate a variety of structures across multiple optical materials. However, femtosecond laser systems are relatively expensive and more difficult to maintain. We present here a low power and low-cost alternative to femtosecond laser ablation, demonstrating random antireflective structures on the surface of Cleartran ZnS windows produced with a continuous-wave laser. In particular, we find that irradiation with a low-powered (<10 mW), defocused, CW 325nm-wavelength laser produces a random surface with significant roughness on ZnS substrates. The transmission through the structured ZnS windows is shown to increase by up to 9% across a broad wavelength range from the visible to the near-infrared.
Dura, Joseph A.; Pierce, Donald J.; Majkrzak, Charles F.; Maliszewskyj, Nicholas C.; McGillivray, Duncan J.; Lösche, Mathias; O'Donovan, Kevin V.; Mihailescu, Mihaela; Perez-Salas, Ursula; Worcester, David L.; White, Stephen H.
2011-01-01
An elastic neutron scattering instrument, the advanced neutron diffractometer/reflectometer (AND/R), has recently been commissioned at the National Institute of Standards and Technology Center for Neutron Research. The AND/R is the centerpiece of the Cold Neutrons for Biology and Technology partnership, which is dedicated to the structural characterization of thin films and multilayers of biological interest. The instrument is capable of measuring both specular and nonspecular reflectivity, as well as crystalline or semicrystalline diffraction at wave-vector transfers up to approximately 2.20 Å−1. A detailed description of this flexible instrument and its performance characteristics in various operating modes are given. PMID:21892232
Artist concept of STS-34 SSBUV in orbit calibration
NASA Technical Reports Server (NTRS)
1989-01-01
Artist concept titled SSBUV IN ORBIT CALIBRATION shows how the shuttle solar backscatter ultraviolet (UV) (SSBUV) instrument will calibrate ozone measuring space-based instruments on the National Oceanic and Atmospheric Administration's (NOAA's) TIROS satellites NOAA-9 and NOAA-11. During STS-34, SSBUV instruments mounted in get away special (GAS) canisters in Atlantis', Orbiter Vehicle (OV) 104's, payload bay will use the Space Shuttle's orbital flight path to assess instrument performance by directly comparing data from identical instruments aboard the TIROS satellite, as OV-104 and the satellite pass over the same Earth location within a one-hour window. SSBUV is managed by NASA's Goddard Space Flight Center (GSFC). Alternate number on image is E66.001.
Low-resistivity photon-transparent window attached to photo-sensitive silicon detector
Holland, Stephen Edward
2000-02-15
The invention comprises a combination of a low resistivity, or electrically conducting, silicon layer that is transparent to long or short wavelength photons and is attached to the backside of a photon-sensitive layer of silicon, such as a silicon wafer or chip. The window is applied to photon sensitive silicon devices such as photodiodes, charge-coupled devices, active pixel sensors, low-energy x-ray sensors and other radiation detectors. The silicon window is applied to the back side of a photosensitive silicon wafer or chip so that photons can illuminate the device from the backside without interference from the circuit printed on the frontside. A voltage sufficient to fully deplete the high-resistivity photosensitive silicon volume of charge carriers is applied between the low-resistivity back window and the front, patterned, side of the device. This allows photon-induced charge created at the backside to reach the front side of the device and to be processed by any circuitry attached to the front side. Using the inventive combination, the photon sensitive silicon layer does not need to be thinned beyond standard fabrication methods in order to achieve full charge-depletion in the silicon volume. In one embodiment, the inventive backside window is applied to high resistivity silicon to allow backside illumination while maintaining charge isolation in CCD pixels.
NASA Astrophysics Data System (ADS)
Cornet, T.; Altobelli, N.; Sotin, C.; Le Mouelic, S.; Rodriguez, S.; Philippe, S.; Brown, R. H.; Barnes, J. W.; Buratti, B. J.; Baines, K. H.; Clark, R. N.; Nicholson, P. D.
2014-12-01
Due to the influence of methane gas and a thick aerosols haze in the atmosphere, Titan's surface is only visible in 7 spectral atmospheric windows centered at 0.93, 1.08, 1.27, 1.59, 2.01, 2.7-2.8 and 5 microns with the Cassini Visual and Infrared Mapping Spectrometer (VIMS). The 5 microns atmospheric window constitutes the only one being almost insensitive to the haze scattering and which presents only a reduced atmospheric absorption contribution to the signal recorded by the instrument. Despite these advantages leading to the almost direct view of the surface, the 5 microns window is also the noisiest spectral window of the entire VIMS spectrum (an effect highly dependent on the time exposure used for the observations), and it is not totally free from atmospheric contributions, enough to keep "artefacts" in mosaics of several thousands of cubes due to atmospheric and surface photometric effects amplified by the very heterogeneous viewing conditions between each Titan flyby. At first order, a lambertian surface photometry at 5 microns has been used as an initial parameter in order to estimate atmospheric opacity and surface photometry in all VIMS atmospheric windows and to determine the albedo of the surface, yet unknown, both using radiative transfer codes on single cubes or empirical techniques on global hyperspectral mosaics. Other studies suggested that Titan's surface photometry would not be uniquely lambertian but would also contain anisotropic lunar-like contributions. In the present work, we aim at constraining accurately the surface photometry of Titan and residual atmospheric absorption effects in this 5 microns window using a comprehensive study of relevant sites located at various latitudes. Those include bright and dark (dunes) terrains, 5-microns bright terrains (Hotei Regio and Tui Regio), the Huygens Landing Site and high latitudes polar lakes and seas. The VIMS 2004 to 2014 database, composed of more than 40,000 hyperspectral cubes acquired on Titan, has been decomposed into a MySQL relational database in order to perform the present study looking at both spatial and temporal (seasonal) aspects.
A conceptual design study for a two-dimensional, electronically scanned thinned array radiometer
NASA Technical Reports Server (NTRS)
Mutton, Philip; Chromik, Christopher C.; Dixon, Iain; Statham, Richard B.; Stillwagen, Frederic H.; Vontheumer, Alfred E.; Sasamoto, Washito A.; Garn, Paul A.; Cosgrove, Patrick A.; Ganoe, George G.
1993-01-01
A conceptual design for the Two-Dimensional, Electronically Steered Thinned Array Radiometer (ESTAR) is described. This instrument is a synthetic aperture microwave radiometer that operates in the L-band frequency range for the measurement of soil moisture and ocean salinity. Two auxiliary instruments, an 8-12 micron, scanning infrared radiometer and a 0.4-1.0 micron, charge coupled device (CCD) video camera, are included to provided data for sea surface temperature measurements and spatial registration of targets respectively. The science requirements were defined by Goddard Space Flight Center. Instrument and the spacecraft configurations are described for missions using the Pegasus and Taurus launch vehicles. The analyses and design trades described include: estimations of size, mass and power, instrument viewing coverage, mechanical design trades, structural and thermal analyses, data and communications performance assessments, and cost estimation.
Roome, Christopher J.; Kuhn, Bernd
2014-01-01
Chronic cranial windows have been instrumental in advancing optical studies in vivo, permitting long-term, high-resolution imaging in various brain regions. However, once a window is attached it is difficult to regain access to the brain under the window for cellular manipulations. Here we describe a simple device that combines long term in vivo optical imaging with direct brain access via glass or quartz pipettes and metal, glass, or quartz electrodes for cellular manipulations like dye or drug injections and electrophysiological stimulations or recordings while keeping the craniotomy sterile. Our device comprises a regular cranial window glass coverslip with a drilled access hole later sealed with biocompatible silicone. This chronic cranial window with access port is cheap, easy to manufacture, can be mounted just as the regular chronic cranial window, and is self-sealing after retraction of the pipette or electrode. We demonstrate that multiple injections can be performed through the silicone port by repetitively bolus loading calcium sensitive dye into mouse barrel cortex and recording spontaneous cellular activity over a period of weeks. As an example to the extent of its utility for electrophysiological recording, we describe how simple removal of the silicone seal can permit patch pipette access for whole-cell patch clamp recordings in vivo. During these chronic experiments we do not observe any infections under the window or impairment of animal health. PMID:25426027
The round window region and contiguous areas: endoscopic anatomy and surgical implications.
Marchioni, Daniele; Alicandri-Ciufelli, Matteo; Pothier, David D; Rubini, Alessia; Presutti, Livio
2015-05-01
The round window region is a critical area of the middle ear; the aim of this paper is to describe its anatomy from an endoscopic perspective, emphasizing some structures, the knowledge of which could have important implications during surgery, as well as to evaluate what involvement cholesteatoma may have with these structures. Retrospective review of video recordings of endoscopic ear surgeries and retrospective database review were conducted in Tertiary university referral center. Videos from endoscopic middle ear procedures carried out between June 2010 and September 2012 and stored in a shared database were reviewed retrospectively. Surgeries in which an endoscopic magnification of the round window region and the inferior retrotympanum area was performed intraoperatively were included in the study. Involvement by cholesteatoma of those regions was also documented based on information obtained from the surgical database. Conformation of the tegmen of the round window niche may influence the surgical view of round window membrane. A structure connecting the round window area to the petrous apex, named the subcochlear canaliculus, is described. Cholesteatoma can invade the round window areas in some patients. Endoscopic approaches can guarantee a very detailed view and allow the exploration of the round window region. Exact anatomical knowledge of this region can have important advantages during surgery, since some pathology can invade inside cavities or tunnels otherwise not seen by instrumentation that produces a straight-line view (e.g. microscope).
Opto-mechanical design of optical window for aero-optics effect simulation instruments
NASA Astrophysics Data System (ADS)
Wang, Guo-ming; Dong, Dengfeng; Zhou, Weihu; Ming, Xing; Zhang, Yan
2016-10-01
A complete theory is established for opto-mechanical systems design of the window in this paper, which can make the design more rigorous .There are three steps about the design. First, the universal model of aerodynamic environment is established based on the theory of Computational Fluid Dynamics, and the pneumatic pressure distribution and temperature data of optical window surface is obtained when aircraft flies in 5-30km altitude, 0.5-3Ma speed and 0-30°angle of attack. The temperature and pressure distribution values for the maximum constraint is selected as the initial value of external conditions on the optical window surface. Then, the optical window and mechanical structure are designed, which is also divided into two parts: First, mechanical structure which meet requirements of the security and tightness is designed. Finally, rigorous analysis and evaluation are given about the structure of optics and mechanics we have designed. There are two parts to be analyzed. First, the Fluid-Solid-Heat Coupled Model is given based on finite element analysis. And the deformation of the glass and structure can be obtained by the model, which can assess the feasibility of the designed optical windows and ancillary structure; Second, the new optical surface is fitted by Zernike polynomials according to the deformation of the surface of the optical window, which can evaluate imaging quality impact of spectral camera by the deformation of window.
Hayashi, Motohiro; Chernov, Mikhail F; Tamura, Noriko; Yomo, Shoji; Tamura, Manabu; Horiba, Ayako; Izawa, Masahiro; Muragaki, Yoshihiro; Iseki, Hiroshi; Okada, Yoshikazu; Ivanov, Pavel; Régis, Jean; Takakura, Kintomo
2013-01-01
Gamma Knife radiosurgery (GKS) is currently performed with 0.1 mm preciseness, which can be designated microradiosurgery. It requires advanced methods for visualizing the target, which can be effectively attained by a neuroimaging protocol based on plain and gadolinium-enhanced constructive interference in steady state (CISS) images. Since 2003, the following thin-sliced images are routinely obtained before GKS of skull base lesions in our practice: axial CISS, gadolinium-enhanced axial CISS, gadolinium-enhanced axial modified time-of-flight (TOF), and axial computed tomography (CT). Fusion of "bone window" CT and magnetic resonance imaging (MRI), and detailed three-dimensional (3D) delineation of the anatomical structures are performed with the Leksell GammaPlan (Elekta Instruments AB). Recently, a similar technique has been also applied to evaluate neuroanatomy before open microsurgical procedures. Plain CISS images permit clear visualization of the cranial nerves in the subarachnoid space. Gadolinium-enhanced CISS images make the tumor "lucid" but do not affect the signal intensity of the cranial nerves, so they can be clearly delineated in the vicinity to the lesion. Gadolinium-enhanced TOF images are useful for 3D evaluation of the interrelations between the neoplasm and adjacent vessels. Fusion of "bone window" CT and MRI scans permits simultaneous assessment of both soft tissue and bone structures and allows 3D estimation and correction of MRI distortion artifacts. Detailed understanding of the neuroanatomy based on application of the advanced neuroimaging protocol permits performance of highly conformal and selective radiosurgical treatment. It also allows precise planning of the microsurgical procedures for skull base tumors.
Building-Integrated Solar Energy Devices based on Wavelength Selective Films
NASA Astrophysics Data System (ADS)
Ulavi, Tejas
A potentially attractive option for building integrated solar is to employ hybrid solar collectors which serve dual purposes, combining solar thermal technology with either thin film photovoltaics or daylighting. In this study, two hybrid concepts, a hybrid photovoltaic/thermal (PV/T) collector and a hybrid 'solar window', are presented and analyzed to evaluate technical performance. In both concepts, a wavelength selective film is coupled with a compound parabolic concentrator (CPC) to reflect and concentrate the infrared portion of the solar spectrum onto a tubular absorber. The visible portion of the spectrum is transmitted through the concentrator to either a thin film Cadmium Telluride (CdTe) solar panel for electricity generation or into the interior space for daylighting. Special attention is given to the design of the hybrid devices for aesthetic building integration. An adaptive concentrator design based on asymmetrical truncation of CPCs is presented for the hybrid solar window concept. The energetic and spectral split between the solar thermal module and the PV or daylighting module are functions of the optical properties of the wavelength selective film and the concentrator geometry, and are determined using a Monte Carlo Ray-Tracing (MCRT) model. Results obtained from the MCRT can be used in conjugation with meteorological data for specific applications to study the impact of CPC design parameters including the half-acceptance angle thetac, absorber diameter D and truncation on the annual thermal and PV/daylighting efficiencies. The hybrid PV/T system is analyzed for a rooftop application in Phoenix, AZ. Compared to a system of the same area with independent solar thermal and PV modules, the hybrid PV/T provides 20% more energy, annually. However, the increase in total delivered energy is due solely to the addition of the thermal module and is achieved at an expense of a decrease in the annual electrical efficiency from 8.8% to 5.8% due to shading by the absorber tubes. For this reason, the PV/T hybrid is not recommended over other options in new installations. The hybrid solar window is evaluated for a horizontal skylight and south and east facing vertical windows in Minneapolis, MN. The predicted visible transmittance for the solar window is 0.66 to 0.73 for single glazed systems and 0.61 to 0.67 for double glazed systems. The solar heat gain coefficient and the U-factor for the window are comparable to existing glazing technology. Annual thermal efficiencies of up to 24% and 26% are predicted for the vertical window and the horizontal skylight respectively. Experimental measurements of the solar thermal component of the window confirm the trends of the model. In conclusion, the hybrid solar window combines the functionality of an energy efficient fenestration system with hybrid thermal energy generation to provide a compelling solution towards sustainable design of the built environment.
Analytical Chemistry and the Microchip.
ERIC Educational Resources Information Center
Lowry, Robert K.
1986-01-01
Analytical techniques used at various points in making microchips are described. They include: Fourier transform infrared spectrometry (silicon purity); optical emission spectroscopy (quantitative thin-film composition); X-ray photoelectron spectroscopy (chemical changes in thin films); wet chemistry, instrumental analysis (process chemicals);…
Mixed Stationary Liquid Phases for Gas-Liquid Chromatography.
ERIC Educational Resources Information Center
Koury, Albert M.; Parcher, Jon F.
1979-01-01
Describes a laboratory technique for use in an undergraduate instrumental analysis course that, using the interpretation of window diagrams, prepares a mixed liquid phase column for gas-liquid chromatography. A detailed procedure is provided. (BT)
The University of Florida's next-generation cryogenic infrared focal plane array controller system
NASA Astrophysics Data System (ADS)
Raines, Steven N.; Boreman, Glenn D.; Eikenberry, Stephen S.; Bandyopadhyay, Reba M.; Quijano, Ismael
2008-07-01
The Infrared Instrumentation Group at the University of Florida has substantial experience building IR focal plane array (FPA) controllers and seamlessly integrating them into the instruments that it builds for 8-meter class observatories, including writing device drivers for UNIX-based computer systems. We report on a design study to investigate implementing an ASIC from Teledyne Imaging Systems (TIS) into our IR FPA controller while simultaneously replacing TIS's interface card with one that eliminates the requirement for a Windows-OS computer within the instrument's control system.
Thin film solar cell configuration and fabrication method
Menezes, Shalini
2009-07-14
A new photovoltaic device configuration based on an n-copper indium selenide absorber and a p-type window is disclosed. A fabrication method to produce this device on flexible or rigid substrates is described that reduces the number of cell components, avoids hazardous materials, simplifies the process steps and hence the costs for high volume solar cell manufacturing.
Mooring Operations for Thin-Ice Arctic Acoustic Window (THAAW) Project
2015-05-20
Moore, S. E., Lee, C. M., Vigness -Raposa, K. J., Freitag, L., Arrott, M., Atakan, K., Beszczynska-Möller, A., Duda, T. F., Dushaw, B. D., Gascard, J...PUBLICATIONS AND PRESENTATIONS Mikhalevsky, P. N., Sagen, H., Worcester, P. F., Baggeroer, A. B., Orcutt, J., Moore, S. E., Lee, C. M., Vigness -Raposa, K. J
Characterization of TimepixCam, a fast imager for the time-stamping of optical photons
NASA Astrophysics Data System (ADS)
Nomerotski, Andrei; Chakaberia, I.; Fisher-Levine, M.; Janoska, Z.; Takacs, P.; Tsang, T.
2017-01-01
We describe the characterization of TimepixCam, a novel camera used to time-stamp optical photons. The camera employs a specialized silicon sensor with a thin entrance window, read out by a Timepix ASIC. TimepixCam is able to record and time-stamp light flashes exceeding 1,000 photons with 15 ns time resolution. Specially produced photodiodes were used to evaluate the quantum efficiency, which was determined to be higher than 90% in the wavelength range of 430-900 nm. The quantum efficiency, sensitivity and ion detection efficiency were compared for a variety of sensors with different surface treatments. Sensors with the thinnest window, 50 nm, had the best performance.
Molecular matter waves - tools and applications
NASA Astrophysics Data System (ADS)
Juffmann, Thomas; Sclafani, Michele; Knobloch, Christian; Cheshnovsky, Ori; Arndt, Markus
2013-05-01
Fluorescence microscopy allows us to visualize the gradual emergence of a deterministic far-field matter-wave diffraction pattern from stochastically arriving single molecules. We create a slow beam of phthalocyanine molecules via laser desorption from a glass window. The small source size provides the transverse coherence required to observe an interference pattern in the far-field behind an ultra-thin nanomachined grating. There the molecules are deposited onto a quartz window and can be imaged in situ and in real time with single molecule sensitivity. This new setup not only allows for a textbook demonstration of quantum interference, but also enables quantitative explorations of the van der Waals interaction between molecules and material gratings.
ETR CONTROL BUILDING, TRA647, INTERIOR. CONTROL ROOM, CONTEXTUAL VIEW. INSTRUMENT ...
ETR CONTROL BUILDING, TRA-647, INTERIOR. CONTROL ROOM, CONTEXTUAL VIEW. INSTRUMENT PANELS AT REAR OF OPERATOR'S CONSOLE GAVE OPERATOR STATUS OF REACTOR PERFORMANCE, COOLANT-WATER CHARACTERISTICS AND OTHER INDICATORS. WINDOWS AT RIGHT LOOKED INTO ETR BUILDING FIRST FLOOR. CAMERA FACING EAST. INL NEGATIVE NO. HD42-6. Mike Crane, Photographer, 3/2004 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID
NASA Astrophysics Data System (ADS)
Shadgan, Babak; Molavi, Behnam; Reid, W. D.; Dumont, Guy; Macnab, Andrew J.
2010-02-01
Background: Medical and diagnostic applications of near infrared spectroscopy (NIRS) are increasing, especially in operating rooms (OR). Since NIRS is an optical technique, radio frequency (RF) interference from other instruments is unlikely to affect the raw optical data, however, NIRS data processing and signal output could be affected. Methods: We investigated the potential for three common OR instruments: an electrical cautery, an orthopaedic drill and an imaging system, to generate electromagnetic interference (EMI) that could potentially influence NIRS signals. The time of onset and duration of every operation of each device was recorded during surgery. To remove the effects of slow changing physiological variables, we first used a lowpass filter and then selected 2 windows with variable lengths around the moment of device onset. For each instant, variances (energy) and means of the signals in the 2 windows were compared. Results: Twenty patients were studied during ankle surgery. Analysis shows no statistically significant difference in the means and variance of the NIRS signals (p < 0.01) during operation of any of the three devices for all surgeries. Conclusion: This method confirms the instruments evaluated caused no significant interference. NIRS can potentially be used without EMI in clinical environments such as the OR.
Stability of landsat-4 thematic mapper outgassing models
Micijevic, E.; Chander, G.
2006-01-01
Oscillations in radiometric gains of the short wave infrared (SWIR) bands in Landsat-4 (L4) and Landsat-5 (L5) Thematic Mappers (TMs) are observed through an analysis of detector responses to the Internal Calibrator (IC) pulses. The oscillations are believed to be caused by an interference effect due to a contaminant film buildup on the window of the cryogenically cooled dewar that houses these detectors. This process of contamination, referred to as outgassing effects, has been well characterized using an optical thin-film model that relates detector responses to the accumulated film thickness and its growth rate. The current models for L4 TM are based on average detector responses to the second brightest IC lamp and have been derived from three data sets acquired during different times throughout the instrument's lifetime. Unlike in L5 TM outgassing characterization, it was found that the L4 TM responses to all three IC lamps can be used to provide accurate characterization and correction for outgassing effects. The analysis of single detector responses revealed an up to five percent difference in the estimated oscillating periods and also indicated a gradual variation of contaminant growth rate over the focal plane.
NASA Astrophysics Data System (ADS)
Kato, M.; Kurosawa, T.; Saito, N.; Kadni, T. B.; Kim, I. J.; Kim, B. C.; Yi, C.-Y.; Pungkun, V.; Chu, C.-H.
2017-01-01
The supplementary comparison of absorbed dose rate in tissue for beta radiation (APMP.RI(I)-S2) was performed with five national metrology institutes in 2013 and 2014. Two commercial thin window ionization chambers were used as transfer instruments and circulated among the participants. Two of the NMIs measured the calibration coefficients of the chambers in reference fields produced from Pm-147, Kr-85 and Sr-90/Y-90, while the other three measured those only in Sr-90/Y-90 beta-particle field. The degree of equivalence for the participants was determined and this comparison verifies the calibration capabilities of the participating laboratories. In addition, most of the results of this comparison are consistent with another international comparison (EUROMET.RI(I)-S2) reported before this work. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Time-resolved soft-x-ray studies of energy transport in layered and planar laser-driven targets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stradling, G.L.
New low-energy x-ray diagnostic techniques are used to explore energy-transport processes in laser heated plasmas. Streak cameras are used to provide 15-psec time-resolution measurements of subkeV x-ray emission. A very thin (50 ..mu..g/cm/sup 2/) carbon substrate provides a low-energy x-ray transparent window to the transmission photocathode of this soft x-ray streak camera. Active differential vacuum pumping of the instrument is required. The use of high-sensitivity, low secondary-electron energy-spread CsI photocathodes in x-ray streak cameras is also described. Significant increases in sensitivity with only a small and intermittant decrease in dynamic range were observed. These coherent, complementary advances in subkeV, time-resolvedmore » x-ray diagnostic capability are applied to energy-transport investigations of 1.06-..mu..m laser plasmas. Both solid disk targets of a variety of Z's as well as Be-on-Al layered-disk targets were irradiated with 700-psec laser pulses of selected intensity between 3 x 10/sup 14/ W/cm/sup 2/ and 1 x 10/sup 15/ W/cm/sup 2/.« less
Kang, Tae-Woon; Kim, Sung Hyun; Kim, Cheol Hwan; Lee, Sang-Mok; Kim, Han-Ki; Park, Jae Seong; Lee, Jae Heung; Yang, Yong Suk; Lee, Sang-Jin
2017-09-27
Polymer/metal/polymer and polymer/metal/inorganic trilayer-structured transparent electrodes with fluorocarbon plasma polymer thin film heaters have been proposed. The polymer/metal/polymer and polymer/metal/inorganic transparent conducting thin films fabricated on a large-area flexible polymer substrate using a continuous roll-to-roll sputtering process show excellent electrical properties and visible-light transmittance. They also exhibit water-repelling surfaces to prevent wetting and to remove contamination. In addition, the adoption of a fluorocarbon/metal/fluorocarbon film permits an outer bending radius as small as 3 mm. These films have a sheet resistance of less than 5 Ω sq -1 , sufficient to drive light-emitting diode circuits. The thin film heater with the fluorocarbon/Ag/SiN x structure exhibits excellent heating characteristics, with a temperature reaching 180 °C under the driving voltage of 13 V. Therefore, the proposed polymer/metal/polymer and polymer/metal/inorganic transparent conducting electrodes using polymer thin films can be applied in flexible and rollable displays as well as automobile window heaters and other devices.
Wang, Kaikai; He, Junhui
2018-04-04
Thin films that integrate antireflective and antibacterial dual functions are not only scientifically interesting but also highly desired in many practical applications. Unfortunately, very few studies have been devoted to the preparation of thin films with both antireflective and antibacterial properties. In this study, mesoporous silica (MSiO 2 ) thin films with uniformly dispersed Ag nanoparticles (Ag NPs) were prepared through a one-pot process, which simultaneously shows high transmittance, excellent antibacterial activity, and mechanical robustness. The optimal thin-film-coated glass substrate demonstrates a maximum transmittance of 98.8% and an average transmittance of 97.1%, respectively, in the spectral range of 400-800 nm. The growth and multiplication of typical bacteria, Escherichia coli ( E. coli), were effectively inhibited on the coated glass. Pencil hardness test, tape adhesion test, and sponge washing test showed favorable mechanical robustness with 5H pencil hardness, 5A grade adhesion, and functional durability of the coating, which promises great potential for applications in various touch screens, windows for hygiene environments, and optical apparatuses for medical uses such as endoscope, and so on.
Ko, Eun-Byul; Choi, Jae-Seok; Jung, Hyunsung; Choi, Sung-Churl; Kim, Chang-Yeoul
2016-02-01
Transparent conducting oxide (TCO) is widely used for the application of flat panel display like liquid crystal displays and plasma display panel. It is also applied in the field of touch panel, solar cell electrode, low-emissivity glass, defrost window, and anti-static material. Fluorine-doped tin oxide (FTO) thin films were fabricated by spray pyrolysis of ethanol-added FTO precursor solutions. FTO thin film by spray pyrolysis is very much investigated and normally formed at high temperature, about 500 degrees C. However, these days, flexible electronics draw many attentions in the field of IT industry and the research for flexible transparent conducting thin film is also required. In the industrial field, indium-tin oxide (ITO) film on polymer substrate is widely used for touch panel and displays. In this study, we investigated the possibility of FTO thin film formation at relatively low temperature of 250 degrees C. We found out that the control of volume of input precursor and exhaust gases could make it possible to form FTO thin film with a relatively low electrical resistance, less than 100 Ohm/sq and high optical transmittance about 88%.
A high-sensitivity torsional pendulum for polymeric films and fibres
NASA Technical Reports Server (NTRS)
Aghili-Kermani, H.; Obrien, T.; Armeniades, C. D.; Roberts, J. M.
1976-01-01
A free oscillation torsion pendulum is described, which has been designed to measure accurately the dynamic shear modulus and logarithmic decrement of polymeric thin films and fibers, at frequencies of 0.1 to 10 Hz and a temperature range of 4.2 to 450 K. The instrument can also provide in situ tensile deformations of up to 5%. The specimen geometry necessary to obtain reliable modulus measurements with thin films is discussed, and typical data are presented which exhibit hitherto unreported relaxation processes, discernible by this instrument.
NASA Astrophysics Data System (ADS)
Desmaris, Vincent
2018-01-01
We present the advanced micro/nano technological engineering at the atomic level producing state-of-the-art epitaxial NbN thin-films on GaN buffer layers. Furthermore, we report the outstanding performance of the hot electron bolometers fabricated on epitaxial NbN thin films on GaN buffer layers. Finally we present advanced passive devices such as waveguide hybrids, IF hybrids and combiners for the realization of heterodyne THz receivers.
The effect of exit beam phase aberrations on parallel beam coherent x-ray reconstructions
NASA Astrophysics Data System (ADS)
Hruszkewycz, S. O.; Harder, R.; Xiao, X.; Fuoss, P. H.
2010-12-01
Diffraction artifacts from imperfect x-ray windows near the sample are an important consideration in the design of coherent x-ray diffraction measurements. In this study, we used simulated and experimental diffraction patterns in two and three dimensions to explore the effect of phase imperfections in a beryllium window (such as a void or inclusion) on the convergence behavior of phasing algorithms and on the ultimate reconstruction. A predictive relationship between beam wavelength, sample size, and window position was derived to explain the dependence of reconstruction quality on beryllium defect size. Defects corresponding to this prediction cause the most damage to the sample exit wave and induce signature error oscillations during phasing that can be used as a fingerprint of experimental x-ray window artifacts. The relationship between x-ray window imperfection size and coherent x-ray diffractive imaging reconstruction quality explored in this work can play an important role in designing high-resolution in situ coherent imaging instrumentation and will help interpret the phasing behavior of coherent diffraction measured in these in situ environments.
The effect of exit beam phase aberrations on parallel beam coherent x-ray reconstructions.
Hruszkewycz, S O; Harder, R; Xiao, X; Fuoss, P H
2010-12-01
Diffraction artifacts from imperfect x-ray windows near the sample are an important consideration in the design of coherent x-ray diffraction measurements. In this study, we used simulated and experimental diffraction patterns in two and three dimensions to explore the effect of phase imperfections in a beryllium window (such as a void or inclusion) on the convergence behavior of phasing algorithms and on the ultimate reconstruction. A predictive relationship between beam wavelength, sample size, and window position was derived to explain the dependence of reconstruction quality on beryllium defect size. Defects corresponding to this prediction cause the most damage to the sample exit wave and induce signature error oscillations during phasing that can be used as a fingerprint of experimental x-ray window artifacts. The relationship between x-ray window imperfection size and coherent x-ray diffractive imaging reconstruction quality explored in this work can play an important role in designing high-resolution in situ coherent imaging instrumentation and will help interpret the phasing behavior of coherent diffraction measured in these in situ environments.
Statistical analysis of data and modeling of Nanodust measured by STEREO/WAVES at 1AU
NASA Astrophysics Data System (ADS)
Belheouane, S.; Zaslavsky, A.; Meyer-Vernet, N.; Issautier, K.; Czechowski, A.; Mann, I.; Le Chat, G.; Zouganelis, I.; Maksimovic, M.
2012-12-01
We study the flux of dust particles of nanometer size measured at 1AU by the S/WAVES instrument aboard the twin STEREO spacecraft. When they impact the spacecraft at very high speed, these nanodust particles, first detected by Meyer-Vernet et al. (2009), generate plasma clouds and produce voltage pulses measured by the electric antennas. The Time Domain Sampler (TDS) of the radio and plasma instrument produces temporal windows containing several pulses. We perform a statistical study of the distribution of pulse amplitudes and arrival times in the measuring window during the 2007-2012 period. We interpret the results using simulations of the dynamics of nanodust in the solar wind based on the model of Czechowski and Mann (2010). We also investigate the variations of nanodust fluxes while STEREO rotates about the sunward axis (Roll) ; this reveals that some directions are privilegied.
The Zwicky Transient Facility Camera
NASA Astrophysics Data System (ADS)
Dekany, Richard; Smith, Roger M.; Belicki, Justin; Delacroix, Alexandre; Duggan, Gina; Feeney, Michael; Hale, David; Kaye, Stephen; Milburn, Jennifer; Murphy, Patrick; Porter, Michael; Reiley, Daniel J.; Riddle, Reed L.; Rodriguez, Hector; Bellm, Eric C.
2016-08-01
The Zwicky Transient Facility Camera (ZTFC) is a key element of the ZTF Observing System, the integrated system of optoelectromechanical instrumentation tasked to acquire the wide-field, high-cadence time-domain astronomical data at the heart of the Zwicky Transient Facility. The ZTFC consists of a compact cryostat with large vacuum window protecting a mosaic of 16 large, wafer-scale science CCDs and 4 smaller guide/focus CCDs, a sophisticated vacuum interface board which carries data as electrical signals out of the cryostat, an electromechanical window frame for securing externally inserted optical filter selections, and associated cryo-thermal/vacuum system support elements. The ZTFC provides an instantaneous 47 deg2 field of view, limited by primary mirror vignetting in its Schmidt telescope prime focus configuration. We report here on the design and performance of the ZTF CCD camera cryostat and report results from extensive Joule-Thompson cryocooler tests that may be of broad interest to the instrumentation community.
A conserved quantity in thin body dynamics
NASA Astrophysics Data System (ADS)
Hanna, James; Pendar, Hodjat
We use an example from textile processing to illustrate the utility of a conserved quantity associated with metric symmetry in a thin body. This quantity, when combined with the usual linear and angular momentum currents, allows us to construct a four-parameter family of curves representing the equilibria of a rotating, flowing string. To achieve this, we introduce a non-material action of mixed Lagrangian-Eulerian type, applicable to fixed windows of axially-moving systems. We will point out intriguing similarities with Bernoulli's equation, discuss the effects of axial flow on rotating conservative systems, and make connections with 19th- and 20th-century results on the dynamics of cables.
Aerogel: From Aerospace to Apparel
NASA Technical Reports Server (NTRS)
2001-01-01
Aspen Systems Inc. developed an aerogel-manufacturing process solved the handling problems associated with aerogel-based insulation products. Their aerogels can now be manufactured into blankets, thin sheets, beads, and molded parts; and may be transparent, translucent, or opaque. Aspen made the material effective for window and skylight insulation, non-flammable building insulation, and inexpensive firewall insulation that will withstand fires in homes and buildings, and also assist in the prevention of forest fires. Another Aspen product is Spaceloft(TM); an inexpensive, flexible blanket that incorporates a thin layer of aerogel embedded directly into the fabric. Spaceloft, is incorporated into jackets intended for wear in extremely harsh conditions and activities, such as Antarctic expeditions.
Ambipolar organic thin-film transistor-based nano-floating-gate nonvolatile memory
NASA Astrophysics Data System (ADS)
Han, Jinhua; Wang, Wei; Ying, Jun; Xie, Wenfa
2014-01-01
An ambipolar organic thin-film transistor-based nano-floating-gate nonvolatile memory was demonstrated, with discrete distributed gold nanoparticles, tetratetracontane (TTC), pentacene as the floating-gate layer, tunneling layer, and active layer, respectively. The electron traps at the TTC/pentacene interface were significantly suppressed, which resulted in an ambipolar operation in present memory. As both electrons and holes were supplied in the channel and trapped in the floating-gate by programming/erasing operations, respectively, i.e., one type of charge carriers was used to overwrite the other, trapped, one, a large memory window, extending on both sides of the initial threshold voltage, was realized.
NASA Astrophysics Data System (ADS)
Lyyra-Laitinen, Tiina; Niinimäki, Mia; Töyräs, Juha; Lindgren, Reijo; Kiviranta, Ilkka; Jurvelin, Jukka S.
1999-10-01
Structural alterations associated with early, mostly reversible, degeneration of articular cartilage induce tissue softening, generally preceding fibrillation and, thus, visible changes of the cartilage surface. We have already developed an indentation instrument for measuring arthroscopic stiffness of cartilage with typical thickness >2 mm. The aim of this study was to extend the applicability of the instrument for the measurement of thin (<2 mm) cartilage stiffness. Variations in cartilage thickness, which will not be known during arthroscopy, can nonetheless affect the indentation measurement, and therefore optimization of the indenter dimensions is necessary. First, we used theoretical and finite element models to compare plane-ended and spherical-ended indenters and, then, altered the dimensions to determine the optimal indenter for thin cartilage measurements. Finally, we experimentally validated the optimized indenter using bovine humeral head cartilage. Reference unconfined compression measurements were carried out with a material testing device. The spherical-ended indenter was more insensitive to the alterations in cartilage thickness (20% versus 39% in the thickness range 1.5-5 mm) than the plane-ended indenter. For thin cartilage, the optimal dimensions for the spherical-ended indenter were 0.5 mm for diameter and 0.1 mm for height. The experimental stiffness measurements with this indenter correlated well with the reference measurements (r = 0.811, n = 31, p<0.0001) in the cartilage thickness range 0.7-1.8 mm. We conclude that the optimized indenter is reliable and well suited for the measurement of thin cartilage stiffness.
NASA Astrophysics Data System (ADS)
Eremina, G. M.; Smolin, A. Yu.; Psakhie, S. G.
2018-04-01
Mechanical properties of thin surface layers and coatings are commonly studied using instrumented indentation and scratch testing, where the mechanical response of the coating - substrate system essentially depends on the substrate material. It is quite difficult to distinguish this dependence and take it into account in the course of full-scale experiments due to a multivariative and nonlinear character of the influence. In this study the process of instrumented indentation of a hardening coating formed on different substrates is investigated numerically by the method of movable cellular automata. As a result of modeling, we identified the features of the substrate material influence on the derived mechanical characteristics of the coating - substrate systems and the processes of their deformation and fracture.
NASA Astrophysics Data System (ADS)
Shankar, Mohan; Priestley, Kory; Smith, Nathaniel; Smith, Nitchie; Thomas, Susan; Walikainen, Dale
2015-10-01
The Clouds and Earth's Radiant Energy System (CERES) instruments help to study the impact of clouds on the earth's radiation budget. There are currently five instruments- two each on board Aqua and Terra spacecraft and one on the Suomi NPP spacecraft to measure the earth's reflected shortwave and emitted longwave energy, which represent two components of the earth's radiation energy budget. Flight Models (FM) 1 and 2 are on Terra, FM 3 and 4 are on Aqua, and FM5 is on Suomi NPP. The measurements are made by three sensors on each instrument: a shortwave sensor that measures the 0.3-5 microns wavelength band, a window sensor that measures the water vapor window between 8-12 microns, and a total sensor that measures all incident energy (0.3- >100 microns). The required accuracy of CERES measurements of 0.5% in the longwave and 1% in the shortwave is achieved through an extensive pre-launch ground calibration campaign as well as on-orbit calibration and validation activities. Onorbit calibration is carried out using the Internal Calibration Module (ICM) that consists of a tungsten lamp, blackbodies, and a solar diffuser known as the Mirror Attenuator Mosaic (MAM). The ICM calibration provides information about the stability of the sensors' broadband radiometric gains on-orbit. Several validation studies are conducted in order to monitor the behavior of the instruments in various spectral bands. The CERES Edition-4 data products for the FM1-FM4 instruments incorporate the latest calibration methodologies to improve on the Edition-3 data products. In this paper, we discuss the updated calibration methodology and present some validation studies to demonstrate the improvement in the trends using the CERES Edition-4 data products for all four instruments.
NASA Astrophysics Data System (ADS)
Chen, Hsi-Chao; Jan, Der-Jun; Chen, Chien-Han; Huang, Kuo-Ting; Lo, Yen-Ming; Chen, Sheng-Hui
2011-09-01
The purpose of this research was to compare the optical properties and structure of tungsten oxide (WO3) thin films that was deposited by different sputtering depositions. WO3 thin films deposited by two different depositions of direct current (DC) magnetron sputtering and pulsed DC sputtering. A 99.95% WO3 target was used as the starting material for these depositions. These WO3 thin films were deposited on the ITO glass, PET and silicon substrate by different ratios of oxygen and argon. A shadow moiré interferometer would be introduced to measure the residual stress for PET substrate. RF magnetron sputtering had the large residual stress than the other's depositions. A Raman spectrum could exhibit the phase of oxidation of WO3 thin film by different depositions. At the ratio of oxygen and argon was about 1:1, and the WO3 thin films had the best oxidation. However, it was important at the change of the transmittance (ΔT = Tbleached - Tcolored) between the coloring and bleaching for the smart window. Therefore, we also found the WO3 thin films had the large variation of transmittance between the coloring and bleaching at the gas ratios of oxygen and argon of 1:1.
Thin-film cadmium telluride photovoltaic cells
NASA Astrophysics Data System (ADS)
Compaan, A. D.; Bohn, R. G.
1994-09-01
This report describes work to develop and optimize radio-frequency (RF) sputtering for the deposition of thin films of cadmium telluride (CdTe) and related semiconductors for thin-film solar cells. Pulsed laser physical vapor deposition was also used for exploratory work on these materials, especially where alloying or doping are involved, and for the deposition of cadmium chloride layers. The sputtering work utilized a 2-in diameter planar magnetron sputter gun. The film growth rate by RF sputtering was studied as a function of substrate temperature, gas pressure, and RF power. Complete solar cells were fabricated on tin-oxide-coated soda-lime glass substrates. Currently, work is being done to improve the open-circuit voltage by varying the CdTe-based absorber layer, and to improve the short-circuit current by modifying the CdS window layer.
NASA Technical Reports Server (NTRS)
Cleveland, G.
1977-01-01
Miniature amplifier for bioelectronic instrumentation consumes only about 100 mW and has frequency response flat to within 0.5 dB from 0.14 to 450 Hz. Device consists of five thin film substrates, which contain eight operational amplifiers and seven field-effect transistor dice.
High Performance Thin Layer Chromatography.
ERIC Educational Resources Information Center
Costanzo, Samuel J.
1984-01-01
Clarifies where in the scheme of modern chromatography high performance thin layer chromatography (TLC) fits and why in some situations it is a viable alternative to gas and high performance liquid chromatography. New TLC plates, sample applications, plate development, and instrumental techniques are considered. (JN)
High durability antireflection coatings for silicon and multispectral ZnS
NASA Astrophysics Data System (ADS)
Joseph, Shay; Marcovitch, Orna; Yadin, Ygal; Klaiman, Dror; Koren, Nitzan; Zipin, Hedva
2007-04-01
In the current complex battle field, military platforms are required to operate on land, at sea and in the air in all weather conditions both day and night. In order to achieve such capabilities, advanced electro-optical systems are being constantly developed and improved. These systems such as missile seeker heads, reconnaissance and target acquisition pods and tracking, monitoring and alert systems have external optical components (window or dome) which must remain operational even at extreme environmental conditions. Depending on the intended use of the system, there are a few choices of window and dome materials. Amongst the more common materials one can point out sapphire, ZnS, germanium and silicon. Other materials such as spinel, ALON and yittria may also be considered. Most infrared materials have high indices of refraction and therefore they reflect a large part of radiation. To minimize the reflection and increase the transmission, antireflection (AR) coatings are the most common choice. Since these systems operate at different environments and weather conditions, the coatings must be made durable to withstand these extreme conditions. In cases where the window or dome is made of relatively soft materials such as multispectral ZnS, the coating may also serve as protection for the window or dome. In this work, several antireflection coatings have been designed and manufactured for silicon and multispectral ZnS. The coating materials were chosen to be either oxides or fluorides which are known to have high durability. Ellipsometry measurements were used to characterize the optical constants of the thin films. The effects of the deposition conditions on the optical constants of the deposited thin films and durability of the coatings will be discussed. The coatings were tested according to MIL-STD-810E and were also subjected to rain erosion tests at the University of Dayton Research Institute (UDRI) whirling arm apparatus in which one of the coatings showed no rain drop impact damage at all.
2003-04-04
KENNEDY SPACE CENTER, FLA. - Workers prepare the shrouded Mars Exploration Rover 2 (MER-2) for mating to the lander. Set to launch in Spring 2003, the MER Mission consists of two identical rovers, landing at different regions of Mars, designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
AXAF VETA-I mirror encircled energy measurements and data reduction
NASA Technical Reports Server (NTRS)
Zhao, Ping; Freeman, Mark D.; Hughes, John P.; Kellogg, Edwin M.; Nguyen, Dan T.; Joy, Marshall; Kolodziejczak, Jeffery J.
1992-01-01
The AXAF VETA-I mirror encircled energy was measured with a series of apertures and two flow gas proportional counters at five X-ray energies ranging from 0.28 to 2.3 keV. The proportional counter has a thin plastic window with an opaque wire mesh supporting grid. Depending on the counter position, this mesh can cause the X-ray transmission to vary as much as +/-9 percent, which directly translates into an error in the encircled energy. In order to correct this wire mesh effect, window scan measurements were made, in which the counter was scanned in both horizontal (Y) and vertical (Z) directions with the aperture fixed. Post VETA measurement of the VXDS setup were made to determine the exact geometry and position of the mesh grid. Computer models of the window mesh were developed to simulate the X-ray transmission based on this measurement. The window scan data were fitted to such mesh models and corrections were made. After this study, the mesh effect was well understood and the final results of the encircled energy were obtained with an uncertainty of less than 0.8 percent.
Xie, Jin; Sendek, Austin D; Cubuk, Ekin D; Zhang, Xiaokun; Lu, Zhiyi; Gong, Yongji; Wu, Tong; Shi, Feifei; Liu, Wei; Reed, Evan J; Cui, Yi
2017-07-25
Modern lithium ion batteries are often desired to operate at a wide electrochemical window to maximize energy densities. While pushing the limit of cutoff potentials allows batteries to provide greater energy densities with enhanced specific capacities and higher voltage outputs, it raises key challenges with thermodynamic and kinetic stability in the battery. This is especially true for layered lithium transition-metal oxides, where capacities can improve but stabilities are compromised as wider electrochemical windows are applied. To overcome the above-mentioned challenges, we used atomic layer deposition to develop a LiAlF 4 solid thin film with robust stability and satisfactory ion conductivity, which is superior to commonly used LiF and AlF 3 . With a predicted stable electrochemical window of approximately 2.0 ± 0.9 to 5.7 ± 0.7 V vs Li + /Li for LiAlF 4 , excellent stability was achieved for high Ni content LiNi 0.8 Mn 0.1 Co 0.1 O 2 electrodes with LiAlF 4 interfacial layer at a wide electrochemical window of 2.75-4.50 V vs Li + /Li.
NASA Technical Reports Server (NTRS)
Owen, W. A.
1984-01-01
Low thermal efficiencies in solar receivers are discussed in terms of system design. It is recommended that careful attention be given to the overall thermal systems design, especially to conductive losses about the window and areas of relatively thin insulation. If the cavity design is carefully managed to insure a small, minimally reradiating aperture, the goal of a very high efficiency cavity receiver is a realistic one.
NASA Astrophysics Data System (ADS)
Gesheva, K.; Ivanova, T.; Bodurov, G.; Szilágyi, I. M.; Justh, N.; Kéri, O.; Boyadjiev, S.; Nagy, D.; Aleksandrova, M.
2016-02-01
“Smart windows” are envisaged for future low-energy, high-efficient architectural buildings, as well as for the car industry. By switching from coloured to fully bleached state, these windows regulate the energy of solar flux entering the interior. Functional layers in these devices are the transition metals oxides. The materials (transitional metal oxides) used in smart windows can be also applied as photoelectrodes in water splitting photocells for hydrogen production or as photocatalytic materials for self-cleaning surfaces, waste water treatment and pollution removal. Solar energy utilization is recently in the main scope of numerous world research laboratories and energy organizations, working on protection against conventional fuel exhaustion. The paper presents results from research on transition metal oxide thin films, fabricated by different methods - atomic layer deposition, atmospheric pressure chemical vapour deposition, physical vapour deposition, and wet chemical methods, suitable for flowthrough production process. The lower price of the chemical deposition processes is especially important when the method is related to large-scale glazing applications. Conclusions are derived about which processes are recently considered as most prospective, related to electrochromic materials and devices manufacturing.
Creep analysis of solid oxide fuel cell with bonded compliant seal design
NASA Astrophysics Data System (ADS)
Jiang, Wenchun; Zhang, Yucai; Luo, Yun; Gong, J. M.; Tu, S. T.
2013-12-01
Solid oxide fuel cell (SOFC) requires good sealant because it works in harsh conditions (high temperature, thermal cycle, oxidative and reducing gas environments). Bonded compliant seal (BCS) is a new sealing method for planar SOFC. It uses a thin foil metal to bond the window frame and cell, achieving the seal between window frame and cell. At high temperature, a comprehensive evaluation of its creep strength is essential for the adoption of BCS design. In order to characterize the creep behavior, the creep induced by thermal stresses in SOFC with BCS design is simulated by finite element method. The results show that the foil is compressed and large thermal stresses are generated. The initial peak thermal stress is located in the thin foil because the foil acts as a spring stores the thermal stresses by elastic and plastic deformation in itself. Serving at high temperature, initial thermal displacement is partially recovered because of the creep relaxation, which becomes a new discovered advantage for BCS design. It predicts that the failures are likely to happen in the middle of the cell edge and BNi-2 filler metal, because the maximum residual displacement and creep strain are located.
Ground-based remote sensing of thin clouds in the Arctic
NASA Astrophysics Data System (ADS)
Garrett, T. J.; Zhao, C.
2012-11-01
This paper describes a method for using interferometer measurements of downwelling thermal radiation to retrieve the properties of single-layer clouds. Cloud phase is determined from ratios of thermal emission in three "micro-windows" where absorption by water vapor is particularly small. Cloud microphysical and optical properties are retrieved from thermal emission in two micro-windows, constrained by the transmission through clouds of stratospheric ozone emission. Assuming a cloud does not approximate a blackbody, the estimated 95% confidence retrieval errors in effective radius, visible optical depth, number concentration, and water path are, respectively, 10%, 20%, 38% (55% for ice crystals), and 16%. Applied to data from the Atmospheric Radiation Measurement program (ARM) North Slope of Alaska - Adjacent Arctic Ocean (NSA-AAO) site near Barrow, Alaska, retrievals show general agreement with ground-based microwave radiometer measurements of liquid water path. Compared to other retrieval methods, advantages of this technique include its ability to characterize thin clouds year round, that water vapor is not a primary source of retrieval error, and that the retrievals of microphysical properties are only weakly sensitive to retrieved cloud phase. The primary limitation is the inapplicability to thicker clouds that radiate as blackbodies.
Directed self-assembly of block copolymer films on atomically-thin graphene chemical patterns
Chang, Tzu-Hsuan; Xiong, Shisheng; Jacobberger, Robert M.; ...
2016-08-16
Directed self-assembly of block copolymers is a scalable method to fabricate well-ordered patterns over the wafer scale with feature sizes below the resolution of conventional lithography. Typically, lithographically-defined prepatterns with varying chemical contrast are used to rationally guide the assembly of block copolymers. The directed self-assembly to obtain accurate registration and alignment is largely influenced by the assembly kinetics. Furthermore, a considerably broad processing window is favored for industrial manufacturing. Using an atomically-thin layer of graphene on germanium, after two simple processing steps, we create a novel chemical pattern to direct the assembly of polystyreneblock-poly(methyl methacrylate). Faster assembly kinetics aremore » observed on graphene/germanium chemical patterns than on conventional chemical patterns based on polymer mats and brushes. This new chemical pattern allows for assembly on a wide range of guiding periods and along designed 90° bending structures. We also achieve density multiplication by a factor of 10, greatly enhancing the pattern resolution. Lastly, the rapid assembly kinetics, minimal topography, and broad processing window demonstrate the advantages of inorganic chemical patterns composed of hard surfaces.« less
Characterizing the appearance and growth of amyloid plaques in APP/PS1 mice
Yan, Ping; Bero, Adam W.; Cirrito, John R.; Xiao, Qingli; Hu, Xiaoyan; Wang, Yan; Gonzales, Ernesto; Holtzman, David M.; Lee, Jin-Moo
2009-01-01
Amyloid plaques are primarily composed of extracellular aggregates of amyloid-beta (Aβ) peptide and are a pathological signature of Alzheimer's disease (AD). However, the factors that influence the dynamics of amyloid plaque formation and growth in vivo are largely unknown. Using serial intravital multiphoton microscopy through a thinned-skull cranial window in APP/PS1 transgenic mice, we have found that amyloid plaques appear and grow over a period of weeks before reaching a mature size. Growth was more prominent early after initial plaque formation: plaques grew faster in 6 month-old compared to 10 month-old mice. Plaque growth rate was also size-related, as smaller plaques exhibited more rapid growth relative to larger plaques. Alterations in interstitial Aβ concentrations were associated with changes in plaque growth. Parallel studies using multiphoton microscopy and in vivo microdialysis revealed that pharmacological reduction of soluble extracellular Aβ by as little as 20-25% was associated with a dramatic decrease in plaque formation and growth. Furthermore, this small reduction in Aβ synthesis was sufficient to reduce amyloid plaque load in 6 month-old but not 10 month-old mice, suggesting that treatment early in disease pathogenesis may be more effective than later treatment. In contrast to thinned-skull windows, no significant plaque growth was observed under open-skull windows, which demonstrated extensive microglial and astrocytic activation. Together, these findings indicate that individual amyloid plaque growth in vivo occurs over a period of weeks and may be influenced by interstitial Aβ concentration as well as reactive gliosis. PMID:19710322
Guns, P-J; Johnson, DM; Van Op den bosch, J; Weltens, E; Lissens, J
2012-01-01
BACKGROUND AND PURPOSE QT prolongation is commonly used as a surrogate marker for Torsade de Pointes (TdP) risk of non-cardiovascular drugs. However, use of this indirect marker often leads to misinterpretation of the realistic TdP risk, as tested compounds may cause QT prolongation without evoking TdP in humans. A negative electro-mechanical (E-M) window has recently been proposed as an alternative risk marker for TdP in a canine LQT1 model. Here, we evaluated the E-M window in anaesthetized guinea pigs as a screening marker for TdP in humans. EXPERIMENTAL APPROACH The effects of various reference drugs and changes in body temperature on the E-M window were assessed in instrumented guinea pigs. The E-M window was defined as the delay between the duration of the electrical (QT interval) and mechanical (QLVPend) systole. KEY RESULTS Drugs with known TdP liability (quinidine, haloperidol, domperidone, terfenadine, thioridazine and dofetilide), but not those with no TdP risk in humans (salbutamol and diltiazem) consistently decreased the E-M window. Interestingly, drugs with known clinical QT prolongation, but with low risk for TdP (amiodarone, moxifloxacin and ciprofloxacin) did not decrease the E-M window. Furthermore, the E-M window was minimally affected by changes in heart rate or body temperature. CONCLUSIONS AND IMPLICATIONS A decreased E-M window was consistently observed with drugs already known to have high TdP risk, but not with drugs with low or no TdP risk. These results suggest that the E-M window in anaesthetized guinea pigs is a risk marker for TdP in humans. PMID:22122450
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kawasaki, Tadahiro; PRESTO-JST, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012; Ueda, Kouta
We have developed an improved, windowed type environmental-cell (E-cell) transmission electron microscope (TEM) for in situ observation of gas-solid interactions, such as catalytic reactions at atmospheric pressure. Our E-cell TEM includes a compact E-cell specimen holder with mechanical stability, resulting in smoother introduction of the desired gases compared with previous E-cell TEMs. In addition, the gas control unit was simplified by omitting the pressure control function of the TEM pre-evacuation chamber. This simplification was due to the successful development of remarkably tough thin carbon films as the window material. These films, with a thickness of <10 nm, were found tomore » withstand pressure differences >2 atm. Appropriate arrangement of the specimen position inside the E-cell provided quantitatively analyzable TEM images, with no disturbances caused by the windowed films. As an application, we used this E-cell TEM to observe the dynamic shape change in a catalytic gold nanoparticle supported on TiO{sub 2} during the oxidation of CO gas.« less
Flexible thermochromic window based on hybridized VO2/graphene.
Kim, Hyeongkeun; Kim, Yena; Kim, Keun Soo; Jeong, Hu Young; Jang, A-Rang; Han, Seung Ho; Yoon, Dae Ho; Suh, Kwang S; Shin, Hyeon Suk; Kim, TaeYoung; Yang, Woo Seok
2013-07-23
Large-scale integration of vanadium dioxide (VO2) on mechanically flexible substrates is critical to the realization of flexible smart window films that can respond to environmental temperatures to modulate light transmittance. Until now, the formation of highly crystalline and stoichiometric VO2 on flexible substrate has not been demonstrated due to the high-temperature condition for VO2 growth. Here, we demonstrate a VO2-based thermochromic film with unprecedented mechanical flexibility by employing graphene as a versatile platform for VO2. The graphene effectively functions as an atomically thin, flexible, yet robust support which enables the formation of stoichiometric VO2 crystals with temperature-driven phase transition characteristics. The graphene-supported VO2 was capable of being transferred to a plastic substrate, forming a new type of flexible thermochromic film. The flexible VO2 films were then integrated into the mock-up house, exhibiting its efficient operation to reduce the in-house temperature under infrared irradiation. These results provide important progress for the fabrication of flexible thermochromic films for energy-saving windows.
LYMAN - The far ultraviolet explorer
NASA Technical Reports Server (NTRS)
Moos, Warren; Osantowski, John F.
1989-01-01
The LYMAN FUSE mission concept for far ultraviolet astronomy is presented. The wavelength window from 100 to 1200 A provides access to a wide range of important scientific problems in cosmology, galactic structure, stellar evolution, and planetary magnetospheres, which cannot be studied in any other way. The LYMAN FUSE Phase A study is examining in detail mission operations, instrumentation technology, the construction of the instrument module, and the interfaces between the Instrument Module and the Explorer Platform Mission. Most of the mission observing time will be allotted through a competitive Guest Observer program analogous to that in operation for the IUE.
Star-Shaped Crack Pattern of Broken Windows
NASA Astrophysics Data System (ADS)
Vandenberghe, Nicolas; Vermorel, Romain; Villermaux, Emmanuel
2013-04-01
Broken thin brittle plates like windows and windshields are ubiquitous in our environment. When impacted locally, they typically present a pattern of cracks extending radially outward from the impact point. We study the variation of the pattern of cracks by performing controlled transverse impacts on brittle plates over a broad range of impact speed, plate thickness, and material properties, and we establish from experiments a global scaling law for the number of radial cracks incorporating all these parameters. A model based on Griffith’s theory of fracture combining bending elastic energy and fracture energy accounts for our observations. These findings indicate how the postmortem shape of broken samples are related to material properties and impact parameters, a procedure relevant to forensic science, archaeology, or astrophysics.
Characterization of TimepixCam, a fast imager for the time-stamping of optical photons
Nomerotski, Andrei; Chakaberia, I.; Fisher-Levine, M.; ...
2017-01-04
Here we describe the characterization of TimepixCam, a novel camera used to time-stamp optical photons. The camera employs a specialized silicon sensor with a thin entrance window, read out by a Timepix ASIC. TimepixCam is able to record and time-stamp light flashes exceeding 1,000 photons with 15 ns time resolution. Specially produced photodiodes were used to evaluate the quantum efficiency, which was determined to be higher than 90% in the wavelength range of 430–900 nm. The quantum efficiency, sensitivity and ion detection efficiency were compared for a variety of sensors with different surface treatments. We found sensors with the thinnestmore » window, 50 nm, had the best performance.« less
Characterization of TimepixCam, a fast imager for the time-stamping of optical photons
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nomerotski, Andrei; Chakaberia, I.; Fisher-Levine, M.
Here we describe the characterization of TimepixCam, a novel camera used to time-stamp optical photons. The camera employs a specialized silicon sensor with a thin entrance window, read out by a Timepix ASIC. TimepixCam is able to record and time-stamp light flashes exceeding 1,000 photons with 15 ns time resolution. Specially produced photodiodes were used to evaluate the quantum efficiency, which was determined to be higher than 90% in the wavelength range of 430–900 nm. The quantum efficiency, sensitivity and ion detection efficiency were compared for a variety of sensors with different surface treatments. We found sensors with the thinnestmore » window, 50 nm, had the best performance.« less
NASA Astrophysics Data System (ADS)
Kephart, Jason Michael
With a growing population and rising standard of living, the world is in need of clean sources of energy at low cost in order to meet both economic and environmental needs. Solar energy is an abundant resource which is fundamentally adequate to meet all human energy needs. Photovoltaics are an attractive way to safely convert this energy to electricity with little to no noise, moving parts, water, or arable land. Currently, thin-film photovoltaic modules based on cadmium telluride are a low-cost solution with multiple GW/year commercial production, but have lower conversion efficiency than the dominant technology, crystalline silicon. Increasing the conversion efficiency of these panels through optimization of the electronic and optical structure of the cell can further lower the cost of these modules. The front contact of the CdTe thin-film solar cell is critical to device efficiency for three important reasons: it must transmit light to the CdTe absorber to be collected, it must form a reasonably passive interface and serve as a growth template for the CdTe, and it must allow electrons to be extracted from the CdTe. The current standard window layer material, cadmium sulfide, has a low bandgap of 2.4 eV which can block over 20% of available light from being converted to mobile charge carriers. Reducing the thickness of this layer or replacing it with a higher-bandgap material can provide a commensurate increase in device efficiency. When the CdS window is made thinner, a degradation in electronic quality of the device is observed with a reduction in open-circuit voltage and fill factor. One commonly used method to enable a thinner optimum CdS thickness is a high-resistance transparent (HRT) layer between the transparent conducting oxide electrode and window layer. The function of this layer has not been fully explained in the literature, and existing hypotheses center on the existence of pinholes in the window layer which are not consistent with observed results. In this work numerous HRT layers were examined beginning with an empirical optimization to create a SnO2-based HRT which allows significantly reduced CdS thickness while maintaining diode quality. The role of this layer was explored through measurement of band alignment parameters via photoemission. These results suggest a negative correlation of work function to device open-circuit voltage, which implies that non-ideal band alignment at the front interface of CdTe is in large part responsible for the loss of electronic quality. Several scenarios explored through 1-dimensional modeling in the SCAPS program corroborate this theory. A sputter-deposited (Mg,Zn)O layer was tested which allows for complete elimination of the CdS window layer with an increase in open-circuit voltage and near complete transmission of all above-bandgap light. An additional window layer material---sputtered, oxygenated CdS---was explored for its transparency. This material was found only to produce high efficiency devices with an effective buffer layer such as the optimized SnO2-base HRT. The dependence of chemical, optical, electrical, and device properties on oxygen content was explored, and the stability of these devices was determined to depend largely on the minimization of copper in the device. Both sputter-deposited alloy window layers appeared to have tunable electron affinity which was critical to optimizing band alignment and therefore device efficiency. Several scenarios explored through 1-dimensional modeling in the SCAPS program corroborate this theory. Both window layers allowed an AM1.5G efficiency increase from a baseline of approximately 13% to 16%.
High-Reliability Waveguide Vacuum/Pressure Window
NASA Technical Reports Server (NTRS)
Britcliffe, Michael J.; Hanson, Theodore R.; Long, Ezra M.; Montanez, Steven
2013-01-01
The NASA Deep Space Network (DSN) uses commercial waveguide windows on the output waveguide of Ka-band (32 GHz) low-noise amplifiers. Mechanical failure of these windows resulted in an unacceptable loss in tracking time. To address this issue, a new Ka-band WR-28 waveguide window has been designed, fabricated, and tested. The window uses a slab of low-loss, low-dielectric constant foam that is bonded into a 1/2-wave-thick waveguide/flange. The foam is a commercially available, rigid, closed-cell polymethacrylimide. It has excellent electrical properties with a dielectric constant of 1.04, and a loss tangent of 0.01. It is relatively strong with a tensile strength of 1 MPa. The material is virtually impermeable to helium. The finished window exhibits a leak rate of less than 3x10(exp -3)cu cm/s with helium. The material is also chemically resistant and can be cleaned with acetone. The window is constructed by fabricating a window body by brazing a short length of WR-28 copper waveguide into a standard rectangular flange, and machining the resulting part to a thickness of 4.6 mm. The foam is machined to a rectangular shape with a dimension of 7.06x3.53 mm. The foam is bonded into the body with a two-part epoxy. After curing, the excess glue and foam are knife-trimmed by hand. The finished window has a loss of less than 0.08 dB (2%) and a return loss of greater than 25 dB at 32 GHz. This meets the requirements for the DSN application. The window is usable for most applications over the entire 26-to-40-GHz waveguide band. The window return loss can be tuned to a required frequency by var y in g the thickness of the window slightly. Most standard waveguide windows use a thin membrane of material bonded into a recess in a waveguide flange, or sandwiched between two flanges with a polymer seal. Designs using the recessed window are prone to mechanical failure over time due to constraints on the dimensions of the recess that allow the bond to fail. Designs using the sandwich method are often permeable to helium, which prohibits the use of helium leak detection. At the time of this reporting, 40 windows have been produced. Twelve are in operation with a combined operating time of over 30,000 hours without a failure.
NASA Space Astronomy Update 6: Unconventional Windows on the Universe
NASA Technical Reports Server (NTRS)
1992-01-01
Professor Stu Bowyer (University of California at Berkeley) explains the Extreme Ultraviolet Explorer and its telescope in this video. Both instrument and satellite are kept in perfect working condition. The satellite picks up extra galactic objects outside our galaxy.
Diesel Combustion Fundamentals. Phase 1. Volume 1. Technical Report.
1987-07-01
C02 ), oxides of nitrogen (NOx), oxygen (02), and unburned hydrocarbons (HC). The instruments for measuring CO and CO2 emissions were Beckman *1 model...emissions. Oxygen levels in the exhaust were measured with a Beckman model 742 amperometric analyzer. These instruments were installed in a bench...nuing the use of this sensor system. First, the location of the window was such that it did not see a large enough volume of the pre-chamber to
Quantitative Electron Probe Microanalysis: State of the Art
NASA Technical Reports Server (NTRS)
Carpernter, P. K.
2005-01-01
Quantitative electron-probe microanalysis (EPMA) has improved due to better instrument design and X-ray correction methods. Design improvement of the electron column and X-ray spectrometer has resulted in measurement precision that exceeds analytical accuracy. Wavelength-dispersive spectrometer (WDS) have layered-dispersive diffraction crystals with improved light-element sensitivity. Newer energy-dispersive spectrometers (EDS) have Si-drift detector elements, thin window designs, and digital processing electronics with X-ray throughput approaching that of WDS Systems. Using these systems, digital X-ray mapping coupled with spectrum imaging is a powerful compositional mapping tool. Improvements in analytical accuracy are due to better X-ray correction algorithms, mass absorption coefficient data sets,and analysis method for complex geometries. ZAF algorithms have ban superceded by Phi(pz) algorithms that better model the depth distribution of primary X-ray production. Complex thin film and particle geometries are treated using Phi(pz) algorithms, end results agree well with Monte Carlo simulations. For geological materials, X-ray absorption dominates the corretions end depends on the accuracy of mass absorption coefficient (MAC) data sets. However, few MACs have been experimentally measured, and the use of fitted coefficients continues due to general success of the analytical technique. A polynomial formulation of the Bence-Albec alpha-factor technique, calibrated using Phi(pz) algorithms, is used to critically evaluate accuracy issues and can be also be used for high 2% relative and is limited by measurement precision for ideal cases, but for many elements the analytical accuracy is unproven. The EPMA technique has improved to the point where it is frequently used instead of the petrogaphic microscope for reconnaissance work. Examples of stagnant research areas are: WDS detector design characterization of calibration standards, and the need for more complete treatment of the continuum X-ray fluorescence correction.
Drawing of STS-34 SSBUV orbiter interface and command and status monitoring
NASA Technical Reports Server (NTRS)
1989-01-01
Line drawing titled SSBUV ORBITER INTERFACE FOR COMMAND AND STATUS MONITORING shows how the shuttle solar backscatter ultraviolet (UV) (SSBUV) will be operated by crewmembers on the aft flight deck using a autonomous payload controller (APC). SSBUV instrument will calibrate ozone measuring space-based instruments on the National Oceanic and Atmospheric Administration's (NOAA's) TIROS satellites NOAA-9 and NOAA-11. During STS-34, SSBUV instruments mounted in get away special (GAS) canisters in Atlantis', Orbiter Vehicle (OV) 104's, payload bay will use the Space Shuttle's orbital flight path to assess instrument performance by directly comparing data from identical instruments aboard the TIROS satellite, as OV-104 and the satellite pass over the same Earth location within a one-hour window. SSBUV is managed by NASA's Goddard Space Flight Center (GSFC).
NASA Astrophysics Data System (ADS)
Li, Zhong; Vikram Singh, Amit; Rastogi, Ankur; Gazquez, Jaume; Borisevich, Albina Y.; Mishra, Rohan; Gupta, Arunava
2017-07-01
Thin films of magnetic garnet materials, e.g. yttrium iron garnet (Y3Fe5O12, YIG), are useful for a variety of applications including microwave integrated circuits and spintronics. Substitution of rare earth ions, such as cerium, is known to enhance the magneto-optic Kerr effect (MOKE) as compared to pure YIG. Thin films of Ce0.75Y2.25Fe5O12 (Ce:YIG) have been grown using the pulsed laser deposition (PLD) technique and their crystal structure examined using high resolution scanning transmission electron microscopy. Homogeneous substitution of Ce in YIG, without oxidation to form a separate CeO2 phase, can be realized in a narrow process window with resulting enhancement of the MOKE signal. The thermally generated signal due to spin Seebeck effect for the optimally doped Ce:YIG films has also been investigated.
Ultra-thin plasma radiation detector
Friedman, Peter S.
2017-01-24
A position-sensitive ionizing-radiation counting detector includes a radiation detector gas chamber having at least one ultra-thin chamber window and an ultra-thin first substrate contained within the gas chamber. The detector further includes a second substrate generally parallel to and coupled to the first substrate and defining a gas gap between the first substrate and the second substrate. The detector further includes a discharge gas between the substrates and contained within the gas chamber, where the discharge gas is free to circulate within the gas chamber and between the first and second substrates at a given gas pressure. The detector further includes a first electrode coupled to one of the substrates and a second electrode electrically coupled to the first electrode. The detector further includes a first discharge event detector coupled to at least one of the electrodes for detecting a gas discharge counting event in the electrode.
Growth and magnetic properties of multiferroic LaxBi1-xMnO3 thin films
NASA Astrophysics Data System (ADS)
Gajek, M.; Bibes, M.; Wyczisk, F.; Varela, M.; Fontcuberta, J.; Barthélémy, A.
2007-05-01
A comparative study of LaxBi1-xMnO3 thin films grown on SrTiO3 substrates is reported. It is shown that these films grow epitaxially in a narrow pressure-temperature range. A detailed structural and compositional characterization of the films is performed within the growth window. The structure and the magnetization of this system are investigated. We find a clear correlation between the magnetization and the unit-cell volume that we ascribe to Bi deficiency and the resultant introduction of a mixed valence on the Mn ions. On these grounds, we show that the reduced magnetization of LaxBi1-xMnO3 thin films compared to the bulk can be explained quantitatively by a simple model, taking into account the deviation from nominal composition and the Goodenough-Kanamori-Anderson rules of magnetic interactions.
Fang, Jia; Liu, Bofei; Zhao, Ying; Zhang, Xiaodan
2014-08-22
Introducing light trapping structures into thin-film solar cells has the potential to enhance their solar energy harvesting as well as the performance of the cells; however, current strategies have been focused mainly on harvesting photons without considering the light re-escaping from cells in two-dimensional scales. The lateral out-coupled solar energy loss from the marginal areas of cells has reduced the electrical yield indeed. We therefore herein propose a lateral light trapping structure (LLTS) as a means of improving the light-harvesting capacity and performance of cells, achieving a 13.07% initial efficiency and greatly improved current output of a-Si:H single-junction solar cell based on this architecture. Given the unique transparency characteristics of thin-film solar cells, this proposed architecture has great potential for integration into the windows of buildings, microelectronics and other applications requiring transparent components.
Hybrid Physical Vapor Deposition Instrument for Advanced Functional Multilayers and Materials
2016-04-27
Hybrid Physical Vapor Deposition Instrument for Advanced Functional Multilayers and Materials PI Maria received support to construct a physical...vapor deposition (PVD) system that combines electron beam (e- beam) evaporation, magnetron sputtering, pulsed laser ablation, and ion-assisted deposition ...The instrumentation enables clean, uniform, and rapid deposition of a wide variety of metallic, semiconducting, and ceramic thin films with
Asay window: A new spall diagnostic
NASA Astrophysics Data System (ADS)
McCluskey, Craig W.; Wilke, Mark D.; Anderson, William W.; Byers, Mark E.; Holtkamp, David B.; Rigg, Paulo A.; Furnish, Michael D.; Romero, Vincent T.
2006-11-01
By changing from the metallic foil of the Asay foil diagnostic, which can detect ejecta from a shocked surface, to a lithium fluoride (LiF) or polymethyl methacrylate (PMMA) window, it is possible to detect multiple spall layers and interlayer rubble. Past experiments to demonstrate this diagnostic have used high explosives (HEs) to shock metals to produce multiple spall layers. Because the exact characteristics of HE-induced spall layers cannot be predetermined, two issues exist in the quantitative interpretation of the data. First, to what level of fidelity is the Asay window method capable of providing quantitative information about spall layers, possibly separated by rubble, and second, contingent on the first, can an analytic technique be developed to convert the data to a meaningful description of spall from a given experiment? In this article, we address the first issue. A layered projectile fired from a gas gun was used to test the new diagnostic's accuracy and repeatability. We impacted a LiF or PMMA window viewed by a velocity interferometer system for any reflector (VISAR) probe with a projectile consisting of four thin stainless steel disks spaced apart 200μm with either vacuum or polyethylene. The window/surface interface velocity measured with a VISAR probe was compared with calculations. The good agreement observed between the adjusted calculation and the measured data indicates that, in principle and given enough prior information, it is possible to use the Asay window data to model a density distribution from spalled material with simple hydrodynamic models and only simple adjustments to nominal predictions.
NASA Astrophysics Data System (ADS)
Shankar, Mohan; Priestley, Kory; Smith, Nitchie; Thomas, Susan; Walikainen, Dale
2014-09-01
The Clouds and Earth's Radiant Energy System (CERES) instruments onboard the Terra and Aqua spacecraft are part of the NASA Earth Observing System (EOS) constellation to make long-term observations of the earth. CERES measures the earth-reflected shortwave energy as well as the earth-emitted thermal energy, which are two components of the earth's radiation energy budget. These measurements are made by five instruments- Flight Models (FM) 1 and 2 onboard Terra, FMs 3 and 4 onboard Aqua and FM5 onboard Suomi NPP. Each instrument comprises three sensors that measure the radiances in different wavelength bands- a shortwave sensor that measures in the 0.3 to 5 micron band, a total sensor that measures all the incident energy (0.3-200 microns) and a window sensor that measures the water-vapor window region of 8 to 12 microns. The stability of the sensors is monitored through on-orbit calibration and validation activities. On-orbit calibration is carried out using the Internal Calibration Module (ICM) that consists of a tungsten lamp, blackbodies, and a solar diffuser known as the Mirror Attenuator Mosaic (MAM). The ICM calibration provides information about the stability of the sensors' broadband radiometric gains on-orbit. Several validation studies are conducted in order to monitor the behavior of the instruments in various spectral bands. The CERES Edition-4 data products for FM1-FM4 incorporate the latest corrections to the sensor responses using the calibration techniques. In this paper, we present the on-orbit performance stability as well as some validation studies used in deriving the CERES Edition-4 data products from all four instruments.
NASA Astrophysics Data System (ADS)
Istratov, A. V.; Gerke, M. N.
2018-01-01
Progress in nano- and microsystem technology is directly related to the development of thin-film technologies. At the present time, thin metal films can serve as the basis for the creation of new instruments for nanoelectronics. One of the important parameters of thin films affecting the characteristics of devices is their optical properties. That is why the island structures, whose optical properties, can change in a wide range depending on their morphology, are of increasing interest. However, despite the large amount of research conducted by scientists from different countries, many questions about the optimal production and use of thin films remain unresolved.
JIRAM-Juno: Overview of Preliminary Results in the Study of Jupiter "Infrared-Bright" Areas
NASA Astrophysics Data System (ADS)
Grassi, Davide; Adriani, Alberto; Bolton, Scott J.
2017-04-01
The JIRAM instrument on board the Juno spacecraft includes a spectrometer channel that operates in the range 2-5 microns with a spectral resolution of about 15 nm. Data from this channel are particularly valuable in the study of bright IR regions, where the upper cloud decks are relatively thin and the thermal radiation emitted at pressures down to 3-5 bars can be measured by infrared remote-sensing instruments. Previous studies using NIMS-Galileo [1] and VIMS-Cassini [2] data, as well as a specific assessment for the JIRAM instrument [3], have demonstrated the possibility of constraining the water, ammonia and phosphine content using moderate-resolution spectra spanning the methane transparency window at 5 microns. While considerable efforts have been devoted to the study of brightest features - the so-called "Hot-Spots", located between the Equatorial zone and the North equatorial Belt - other prominent bright areas over the disk of Jupiter remain largely uninvestigated. This talk reviews preliminary results of the JIRAM observations acquired around the first Juno "perijove" (closest approach of Jupiter) after orbit insertion. In general terms, the retrieved contents of the gaseous species mentioned above agree with the global latitudinal trends presented in [3] and [4]. Nonetheless, in several instances, the spatial capabilities of JIRAM allow one to detect specific spatial trends, likely to be associated to dynamic regimes at regional scale. This work was supported by the Italian Space Agency through ASI-INAF contract I/010/10/0 and 2014-050-R.0. JIL acknowledges support from NASA through the Juno Project. GSO acknowledges support from NASA through funds that were distributed to the Jet Propulsion Laboratory, California Institute of Technology. [1] Irwin et al., 1998, doi:10.1029/98JE00948 [2] Giles et al., 2015, doi:10.1016/j.icarus.2015.05.030 [3] Grassi et al., 2010, doi:10.1016/j.pss.2010.05.003 [4] Giles et al., 2016, arXiv:1610.09073
NASA Technical Reports Server (NTRS)
1989-01-01
Glare from CRT screens has been blamed for blurred vision, eyestrain, headaches, etc. Optical Coating Laboratory, Inc. (OCLI) manufactures a coating to reduce glare which was used to coat the windows on the Gemini and Apollo spacecraft. In addition, OCLI offers anti-glare filters (Glare Guard) utilizing the same thin film coating technology. The coating minimizes brightness, provides enhanced contrast and improves readability. The filters are OCLI's first consumer product.
Photovoltaic devices comprising zinc stannate buffer layer and method for making
Wu, Xuanzhi; Sheldon, Peter; Coutts, Timothy J.
2001-01-01
A photovoltaic device has a buffer layer zinc stannate Zn.sub.2 SnO.sub.4 disposed between the semiconductor junction structure and the transparent conducting oxide (TCO) layer to prevent formation of localized junctions with the TCO through a thin window semiconductor layer, to prevent shunting through etched grain boundaries of semiconductors, and to relieve stresses and improve adhesion between these layers.
Storing and Deploying Solar Panels
NASA Technical Reports Server (NTRS)
Browning, D. L.; Stocker, H. M.; Kleidon, E. H.
1982-01-01
Like upward-drawn window shades, solar blankets are unfurled to length of 89m, almost filling opening in 95.59-meter-square frame. When frame is completely assembled, solar blankets are pulled from canisters, one by one by electric motor. A Thin cushion sheet is rolled up with each blanket to cushion solar cells. Sheet is taken up on roller as blanket is unfurled. Unrolling proceeds automatically.
Dwyer, Jason R; Harb, Maher
2017-09-01
We present a review of the use of selected nanofabricated thin films to deliver a host of capabilities and insights spanning bioanalytical and biophysical chemistry, materials science, and fundamental molecular-level research. We discuss approaches where thin films have been vital, enabling experimental studies using a variety of optical spectroscopies across the visible and infrared spectral range, electron microscopies, and related techniques such as electron energy loss spectroscopy, X-ray photoelectron spectroscopy, and single molecule sensing. We anchor this broad discussion by highlighting two particularly exciting exemplars: a thin-walled nanofluidic sample cell concept that has advanced the discovery horizons of ultrafast spectroscopy and of electron microscopy investigations of in-liquid samples; and a unique class of thin-film-based nanofluidic devices, designed around a nanopore, with expansive prospects for single molecule sensing. Free-standing, low-stress silicon nitride membranes are a canonical structural element for these applications, and we elucidate the fabrication and resulting features-including mechanical stability, optical properties, X-ray and electron scattering properties, and chemical nature-of this material in this format. We also outline design and performance principles and include a discussion of underlying material preparations and properties suitable for understanding the use of alternative thin-film materials such as graphene.
Thin film polarizer and color filter based on photo-polymerizable nematic liquid crystal
NASA Astrophysics Data System (ADS)
Mohammadimasoudi, Mohammad; Neyts, Kristiaan; Beeckman, Jeroen
2015-03-01
We present a method to fabricate a thin film color filter based on a mixture of photo-polymerizable liquid crystal and chiral dopant. A chiral nematic liquid crystal layer reflects light for a certain wavelength interval Δλ (= Δn.P) with the period and Δn the birefringence of the liquid crystal. The reflection band is determined by the chiral dopant concentration. The bandwidth is limited to 80nm and the reflectance is at most 50% for unpolarized incident light. The thin color filter is interesting for innovative applications like polarizer-free reflective displays, polarization-independent devices, stealth technologies, or smart switchable reflective windows to control solar light and heat. The reflected light has strong color saturation without absorption because of the sharp band edges. A thin film polarizer is developed by using a mixture of photo-polymerizable liquid crystal and color-neutral dye. The fabricated thin film absorbs light that is polarized parallel to the c axis of the LC. The obtained polarization ratio is 80% for a film of only 12 μm. The thin film polarizer and the color filter feature excellent film characteristics without domains and can be detached from the substrate which is useful for e.g. flexible substrates.
Yang, Cheng-Fu; Chen, Kai-Huang; Chen, Ying-Chung; Chang, Ting-Chang
2007-09-01
In this study, the Ba(Zr0.1Ti0.9)O3 (BZ1T9) thin films have been well deposited on the Pt/Ti/SiO2/Si substrate. The optimum radio frequency (RF) deposition parameters are developed, and the BZ1T9 thin films deposition at the optimum parameters have the maximum capacitance and dielectric constant of 4.4 nF and 190. As the applied voltage is increased to 8 V, the remnant polarization and coercive field of BZ1T9 thin films are about 4.5 microC/cm2 and 80 kV/cm. The counterclockwise current hysteresis and memory window of n-channel thin-film transistor property are observed, and that can be used to indicate the switching of ferroelectric polarization of BZ1T9 thin films. One-transistor-capacitor (1TC) structure of BZ1T9 ferroelectric random access memory device using bottom-gate amorphous silicon thin-film transistor was desirable because of the smaller size and better sensitivity. The BZ1T9 ferroelectric RAM devices with channel width = 40 microm and channel length = 8 microm has been successfully fabricated and the ID-VG transfer characteristics also are investigated in this study.
Strain-induced phenomenon in complex oxide thin films
NASA Astrophysics Data System (ADS)
Haislmaier, Ryan
Complex oxide materials wield an immense spectrum of functional properties such as ferroelectricity, ferromagnetism, magnetoelectricity, optoelectricity, optomechanical, magnetoresistance, superconductivity, etc. The rich coupling between charge, spin, strain, and orbital degrees of freedom makes this material class extremely desirable and relevant for next generation electronic devices and technologies which are trending towards nanoscale dimensions. Development of complex oxide thin film materials is essential for realizing their integration into nanoscale electronic devices, where theoretically predicted multifunctional capabilities of oxides could add tremendous value. Employing thin film growth strategies such as epitaxial strain and heterostructure interface engineering can greatly enhance and even unlock novel material properties in complex oxides, which will be the main focus of this work. However, physically incorporating oxide materials into devices remains a challenge. While advancements in molecular beam epitaxy (MBE) of thin film oxide materials has led to the ability to grow oxide materials with atomic layer precision, there are still major limitations such as controlling stoichiometric compositions during growth as well as creating abrupt interfaces in multi-component layered oxide structures. The work done in this thesis addresses ways to overcome these limitations in order to harness intrinsic material phenomena. The development of adsorption-controlled stoichiometric growth windows of CaTiO3 and SrTiO3 thin film materials grown by hybrid MBE where Ti is supplied using metal-organic titanium tetraisopropoxide material is thoroughly outlined. These growth windows enable superior epitaxial strain-induced ferroelectric and dielectric properties to be accessed as demonstrated by chemical, structural, electrical, and optical characterization techniques. For tensile strained CaTiO3 and compressive strained SrTiO 3 films, the critical effects of nonstoichiometry on ferroelectric properties are investigated, where enhanced ferroelectric responses are only found for stoichiometric films grown inside of the growth windows, whereas outside of the optimal growth window conditions, ferroelectric properties are greatly deteriorated and eventually disappear for highly nonstoichiometric film compositions. Utilizing these stoichiometric growth windows, high temperature polar phase transitions are discovered for compressively strained CaTiO3 films with transition temperatures in excess of 700 K, rendering this material as a strong candidate for high temperature electronic applications. Beyond the synthesis of single phase materials using hybrid MBE, a methodology is presented for constructing layered (SrTiO3)n/(CaTiO 3)n superlattice structures, where precise control over the unit cell layering thickness (n) is demonstrated using in-situ reflection high energy electron diffraction. The effects of interface roughness and layering periodicity (n) on the strain-induced ferroelectric properties for a series of n=1-10 (SrTiO3)n/(CaTiO3) n superlattice films are investigated. It is found that the stabilization of a ferroelectric phase is independent of n, but is however strongly dominated by the degree of interface roughness which is quantified by measuring the highest nth order X-ray diffraction peak splitting of each superlattice film. A counter-intuitive realization is made whereby a critical amount of interface roughness is required in order to enable the formation of the predicted strain-stabilized ferroelectric phase, whereas sharp interfaces actually suppress this ferroelectric phase from manifesting. It is shown how high-quality complex oxide superlattices can be constructed using hybrid MBE technique, allowing the ability to control layered materials at the atomic scale. Furthermore, a detailed growth methodology is provided for constructing a layered n=4 SrO(SrTiO3)n Ruddlesden-Popper (RP) phase by hybrid MBE, where the ability to deposit single monolayers of SrO and TiO2 is utilized to build the RP film structure over a time period of 5 hours. This is the first time that a thin film RP phase has been grown using hybrid MBE, where an a stable control over the fluxes is demonstrated during relatively long time periods of growth, which advantageously facilitates the synthesis of high-quality RP materials with excellent structural and chemical homogeneity. Additionally, this work demonstrates some major advancements in optical second harmonic generation (SHG) characterization techniques of ferroelectric thin film materials. The SHG characterization techniques developed here proved to be the 'bread-and-butter' for most of the work performed in this thesis, providing a powerful tool for identifying the existence of strain-induced ferroelectric phases, including their temperature dependence and polar symmetry. The work presented in this dissertation will hopefully provide a preliminary road map for future hybrid MBE growers, scientists and researchers, to develop and investigate epitaxial strain and heterostructure layering induced phenomena in other complex oxide systems.
NASA Astrophysics Data System (ADS)
Abbas, Haider; Park, Mi Ra; Abbas, Yawar; Hu, Quanli; Kang, Tae Su; Yoon, Tae-Sik; Kang, Chi Jung
2018-06-01
Improved resistive switching characteristics are demonstrated in a hybrid device with Pt/Ti/MnO (thin film)/MnO (nanoparticle)/Pt structure. The hybrid devices of MnO thin film and nanoparticle assembly were fabricated. MnO nanoparticles with an average diameter of ∼30 nm were chemically synthesized and assembled as a monolayer on a Pt bottom electrode. A MnO thin film of ∼40 nm thickness was deposited on the nanoparticle assembly to form the hybrid structure. Resistive switching could be induced by the formation and rupture of conducting filaments in the hybrid oxide layers. The hybrid device exhibited very stable unipolar switching with good endurance and retention characteristics. It showed a larger and stable memory window with a uniform distribution of SET and RESET voltages. Moreover, the conduction mechanisms of ohmic conduction, space-charge-limited conduction, Schottky emission, and Poole–Frenkel emission have been investigated as possible conduction mechanisms for the switching of the devices. Using MnO nanoparticles in the thin film and nanoparticle heterostructures enabled the appropriate control of resistive random access memory (RRAM) devices and markedly improved their memory characteristics.
Yanagawa, Masahiro; Kusumoto, Masahiko; Johkoh, Takeshi; Noguchi, Masayuki; Minami, Yuko; Sakai, Fumikazu; Asamura, Hisao; Tomiyama, Noriyuki
2018-05-01
Measuring the size of invasiveness on computed tomography (CT) for the T descriptor size was deemed important in the 8th edition of the TNM lung cancer classification. We aimed to correlate the maximal dimensions of the solid portions using both lung and mediastinal window settings on CT imaging with the pathologic invasiveness (> 0.5 cm) in lung adenocarcinoma patients. The study population consisted of 378 patients with a histologic diagnosis of adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), invasive adenocarcinoma (IVA)-lepidic, IVA-acinar and/or IVA-papillary, and IVA-micropapillary and/or solid adenocarcinoma. A panel of 15 radiologists was divided into 2 groups (group A, 9 radiologists; and group B, 6 radiologists). The 2 groups independently measured the maximal and perpendicular dimensions of the solid components and entire tumors on the lung and mediastinal window settings. The solid proportion of nodule was calculated by dividing the solid portion size (lung and mediastinal window settings) by the nodule size (lung window setting). The maximal dimensions of the invasive focus were measured on the corresponding pathologic specimens by 2 pathologists. The solid proportion was larger in the following descending order: IVA-micropapillary and/or solid, IVA-acinar and/or papillary, IVA-lepidic, MIA, and AIS. For both groups A and B, a solid portion > 0.8 cm in the lung window setting or > 0.6 cm in the mediastinal window setting on CT was a significant indicator of pathologic invasiveness > 0.5 cm (P < .001; receiver operating characteristic analysis using Youden's index). A solid portion > 0.8 cm on the lung window setting or solid portion > 0.6 cm on the mediastinal window setting on CT predicts for histopathologic invasiveness to differentiate IVA from MIA and AIS. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.
Program Processes Thermocouple Readings
NASA Technical Reports Server (NTRS)
Quave, Christine A.; Nail, William, III
1995-01-01
Digital Signal Processor for Thermocouples (DART) computer program implements precise and fast method of converting voltage to temperature for large-temperature-range thermocouple applications. Written using LabVIEW software. DART available only as object code for use on Macintosh II FX or higher-series computers running System 7.0 or later and IBM PC-series and compatible computers running Microsoft Windows 3.1. Macintosh version of DART (SSC-00032) requires LabVIEW 2.2.1 or 3.0 for execution. IBM PC version (SSC-00031) requires LabVIEW 3.0 for Windows 3.1. LabVIEW software product of National Instruments and not included with program.
The Assessment of Selectivity in Different Quadrupole-Orbitrap Mass Spectrometry Acquisition Modes
NASA Astrophysics Data System (ADS)
Berendsen, Bjorn J. A.; Wegh, Robin S.; Meijer, Thijs; Nielen, Michel W. F.
2015-02-01
Selectivity of the confirmation of identity in liquid chromatography (tandem) mass spectrometry using Q-Orbitrap instrumentation was assessed using different acquisition modes based on a representative experimental data set constructed from 108 samples, including six different matrix extracts and containing over 100 analytes each. Single stage full scan, all ion fragmentation, and product ion scanning were applied. By generating reconstructed ion chromatograms using unit mass window in targeted MS2, selected reaction monitoring (SRM), regularly applied using triple-quadrupole instruments, was mimicked. This facilitated the comparison of single stage full scan, all ion fragmentation, (mimicked) SRM, and product ion scanning applying a mass window down to 1 ppm. Single factor Analysis of Variance was carried out on the variance (s2) of the mass error to determine which factors and interactions are significant parameters with respect to selectivity. We conclude that selectivity is related to the target compound (mainly the mass defect), the matrix, sample clean-up, concentration, and mass resolution. Selectivity of the different instrumental configurations was quantified by counting the number of interfering peaks observed in the chromatograms. We conclude that precursor ion selection significantly contributes to selectivity: monitoring of a single product ion at high mass accuracy with a 1 Da precursor ion window proved to be equally selective or better to monitoring two transition products in mimicked SRM. In contrast, monitoring a single fragment in all ion fragmentation mode results in significantly lower selectivity versus mimicked SRM. After a thorough inter-laboratory evaluation study, the results of this study can be used for a critical reassessment of the current identification points system and contribute to the next generation of evidence-based and robust performance criteria in residue analysis and sports doping.
A Study of Tropical thin Cirrus Clouds with Supervised Learning
NASA Astrophysics Data System (ADS)
Rodier, S. D.; Hu, Y.; Vaughan, M. A.
2007-12-01
ABSTRACT Accurate knowledge of the temporal frequency and spatial extent of optically thin cirrus is crucial to climate feedback analysis. Current global warming theory asserts that when the atmospheric concentration of CO2 increases, the outgoing longwave radiation at non-window wavelengths is reduced. If the Earth's net radiative balance is to remain stable, ground temperatures must rise in response, thereby increasing thermal emission to space. Current models do not account for subsequent changes in cloud cover, because this aspect of the climate feedback system is so poorly understood. One possible response of the cloud-climate feedback process is an increase in the global occurrence of thin cirrus clouds, driven by the increase in longwave cooling in the upper troposphere that results from higher CO2 concentrations. Exacerbating the difficulty of assessing the situation is the fact that passive remote sensing instruments cannot reliably detect cirrus clouds with optical depths less than ~0.3, because these clouds do not reflect enough sunlight to create a sufficient contrast with the Earth's surface. Now, however, the presence of thin cirrus can for the first time be accurately detected and systematically monitored by the combination of active and passive sensors onboard the CALIPSO satellite. Nevertheless, the data record is still quite limited, as CALIPSO has been in orbit for only 16 months. We have therefore initiated a multi-platform data fusion study to establish a methodology for extending the limited set of CALIPSO measurements to the existing 30-year record of passive remote sensing data, and thus improve our understanding of cloud feedback mechanisms. Using nighttime data from the first 10 days in April 2007 as a training set, we applied a general regression neural network (GRNN) to collocated samples of sea surface temperature (SST) reported by AMSR, brightness temperatures (BT) from the CALIPSO imaging infrared radiometer (IIR), and optical depths (OD) derived from the CALIPSO lidar measurements. The result is an accurate mapping of the optical depths derived from the active sensors to the brightness temperatures computed from the passive sensor measurements. Applying the trained network to this combination of passive sensor parameters, optical depths as small as 0.1 can be reliably retrieved. The relative uncertainties in the retrieval are reasonable, and can be improved significantly by use of a much larger training set.
Design and fabrication of a window for the gas Cherenkov detector 3
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fatherley, V. E., E-mail: vef@lanl.gov; Bingham, D. A.; Cartelli, M. D.
2016-11-15
The gas Cherenkov detector 3 was designed at Los Alamos National Laboratory for use in inertial confinement fusion experiments at both the Omega Laser Facility and the National Ignition Facility. This instrument uses a low-Z gamma-to-electron convertor plate and high pressure gas to convert MeV gammas into UV/visible Cherenkov photons for fast optical detection. This is a follow-on diagnostic from previous versions, with two notable differences: the pressure of the gas is four times higher, and it allows the use of fluorinated gas, requiring metal seals. These changes force significant changes in the window component, having a unique set ofmore » requirements and footprint limitations. The selected solution for this component, a sapphire window brazed into a stainless steel flange housing, is described.« less
Design and fabrication of a window for the Gas Cherenkov Detector 3
Fatherley, Valerie E.; Bingham, David A.; Cartelli, Myles Derrick; ...
2016-08-23
The gas Cherenkov detector 3 was designed at Los Alamos National Laboratory for use in inertial confinement fusion experiments at both the Omega Laser Facility and the National Ignition Facility. This instrument uses a low-Z gamma-to-electron convertor plate and high pressure gas to convert MeV gammas into UV/visible Cherenkov photons for fast optical detection. This is a follow-on diagnostic from previous versions, with two notable differences: the pressure of the gas is four times higher, and it allows the use of fluorinated gas, requiring metal seals. These changes force significant changes in the window component, having a unique set ofmore » requirements and footprint limitations. Finally, the selected solution for this component, a sapphire window brazed into a stainless steel flange housing, is described.« less
New machining method of high precision infrared window part
NASA Astrophysics Data System (ADS)
Yang, Haicheng; Su, Ying; Xu, Zengqi; Guo, Rui; Li, Wenting; Zhang, Feng; Liu, Xuanmin
2016-10-01
Most of the spherical shell of the photoelectric multifunctional instrument was designed as multi optical channel mode to adapt to the different band of the sensor, there were mainly TV, laser and infrared channels. Without affecting the optical diameter, wind resistance and pneumatic performance of the optical system, the overall layout of the spherical shell was optimized to save space and reduce weight. Most of the shape of the optical windows were special-shaped, each optical window directly participated in the high resolution imaging of the corresponding sensor system, and the optical axis parallelism of each sensor needed to meet the accuracy requirement of 0.05mrad.Therefore precision machining of optical window parts quality will directly affect the photoelectric system's pointing accuracy and interchangeability. Processing and testing of the TV and laser window had been very mature, while because of the special nature of the material, transparent and high refractive rate, infrared window parts had the problems of imaging quality and the control of the minimum focal length and second level parallel in the processing. Based on years of practical experience, this paper was focused on how to control the shape and parallel difference precision of infrared window parts in the processing. Single pass rate was increased from 40% to more than 95%, the processing efficiency was significantly enhanced, an effective solution to the bottleneck problem in the actual processing, which effectively solve the bottlenecks in research and production.
SOSPEX, an interactive tool to explore SOFIA spectral cubes
NASA Astrophysics Data System (ADS)
Fadda, Dario; Chambers, Edward T.
2018-01-01
We present SOSPEX (SOFIA SPectral EXplorer), an interactive tool to visualize and analyze spectral cubes obtained with the FIFI-LS and GREAT instruments onboard the SOFIA Infrared Observatory. This software package is written in Python 3 and it is available either through Github or Anaconda.Through this GUI it is possible to explore directly the spectral cubes produced by the SOFIA pipeline and archived in the SOFIA Science Archive. Spectral cubes are visualized showing their spatial and spectral dimensions in two different windows. By selecting a part of the spectrum, the flux from the corresponding slice of the cube is visualized in the spatial window. On the other hand, it is possible to define apertures on the spatial window to show the corresponding spectral energy distribution in the spectral window.Flux isocontours can be overlapped to external images in the spatial window while line names, atmospheric transmission, or external spectra can be overplotted on the spectral window. Atmospheric models with specific parameters can be retrieved, compared to the spectra and applied to the uncorrected FIFI-LS cubes in the cases where the standard values give unsatisfactory results. Subcubes can be selected and saved as FITS files by cropping or cutting the original cubes. Lines and continuum can be fitted in the spectral window saving the results in Jyson files which can be reloaded later. Finally, in the case of spatially extended observations, it is possible to compute spectral momenta as a function of the position to obtain velocity dispersion maps or velocity diagrams.
NASA Astrophysics Data System (ADS)
Anitha, M.; Amalraj, L.; Anitha, N.
2017-12-01
Cadmium oxide (CdO) thin films were prepared with different concentrations of precursor solution (0.05, 0.1, 0.15, 0.2 and 0.25 M, respectively) at the optimized temperature (200 °C) using the nebulized spray pyrolysis technique to obtain better crystallinity in polycrystalline thin films on amorphous glass substrates. The XRD characterization of those samples revealed a preferential orientation along the (111) plane having a cubic structure. The scanning electron microscopy (SEM) analysis displayed that all the as-deposited thin films have spherical shaped grains. The transmittance of the as-deposited CdO thin films had decreased from 88 to 71% for longer wavelength regions (600-900 nm) as the precursor concentration had increased and then increased for higher precursor concentration. The optical band gap was found to lie between 2.45 and 2.40 eV belonging to direct transition for those thin films. The presence of Cd-O bond (540 cm-1) was confirmed by FTIR spectrum. The emission properties of CdO thin films were studied by luminescence spectrum recorded at room temperature. A maximum carrier concentration and minimum resistivity values of 4.743 × 1019 cm- 3 and 1.06 × 10-3 Ω-cm, respectively, were obtained for 0.2 M precursor concentration. These CdO thin films have high optical transmittance and high room temperature conductivity, which can be used as the TCO and Solar cell (window layer) material.
NASA Technical Reports Server (NTRS)
Smith, Kevin
2011-01-01
This tutorial will explain the concepts and steps for interfacing a National Instruments LabView virtual instrument (VI) running on a Windows platform with another computer via the Object Management Group (OMG) Data Distribution Service (DDS) as implemented by the Twin Oaks Computing CoreDX. This paper is for educational purposes only and therefore, the referenced source code will be simplistic and void of all error checking. Implementation will be accomplished using the C programming language.
24-channel dual microcontroller-based voltage controller for ion optics remote control
NASA Astrophysics Data System (ADS)
Bengtsson, L.
2018-05-01
The design of a 24-channel voltage control instrument for Wenzel Elektronik N1130 NIM modules is described. This instrument is remote controlled from a LabVIEW GUI on a host Windows computer and is intended for ion optics control in electron affinity measurements on negative ions at the CERN-ISOLDE facility. Each channel has a resolution of 12 bits and has a normally distributed noise with a standard deviation of <1 mV. The instrument is designed as a standard 2-unit NIM module where the electronic hardware consists of a printed circuit board with two asynchronously operating microcontrollers.
Systematic approach for describing the geometry of spectrophotometry
NASA Astrophysics Data System (ADS)
Early, Edward A.
2003-07-01
In the field of spectrophotometry, the value of the quantities depends upon the geometry under which they are measured. Therefore, it is imperative to completely describe the measurement geometry. Many documentary standards specify the geometry for a particular application. However, to accurately specify the geometry, a general, basic understanding of the relevant parameters for describing the geometry is required. A systematic approach for describing the measurement geometry is presented, which will hopefully have a positive impact on documentary standards. The key to describing the geometry is to consider the illuminator and receiver of the instrument as optical systems with pupils and windows. It is these optical systems, together with the reference plane, that determine the sampling aperture of the instrument. The geometry is then completely described by the relations between the sampling aperture and the optical systems of the illuminator and receiver. These concepts are illustrated by considering three configurations of pupils and windows relative to the focal point of an optical system.
Information content of IRIS spectra. [from Nimbus 4 satellite
NASA Technical Reports Server (NTRS)
Price, J. C.
1974-01-01
Spectra from the satellite instrument IRIS (infra red interferometer spectrometer) were examined to find the number of independent variables needed to describe these broadband high spectral resolution data. The radiated power in the atmospheric window from 771 to 981/cm was the first parameter chosen for fitting observed spectra. At succeeding levels of analysis the residual variability (observed spectrum - best fit spectrum) in an ensemble of observations was partioned into spectral eigenvectors. The eigenvector describing the largest fraction of this variability was examined for a strong spectral signature; the power in the corresponding spectral band was then used as the next fitting parameter. The measured power in nine spectral intervals, when inserted in the spectral fitting functions, was adequate to describe most spectra to within the noise level of IRIS. Considerations of relative signal strength and scales of atmospheric variability suggest a combination sounder (multichannel-broad field of view) scanner (window channel-small field of view) as an efficient observing instrument.
A multi-center study benchmarks software tools for label-free proteome quantification
Gillet, Ludovic C; Bernhardt, Oliver M.; MacLean, Brendan; Röst, Hannes L.; Tate, Stephen A.; Tsou, Chih-Chiang; Reiter, Lukas; Distler, Ute; Rosenberger, George; Perez-Riverol, Yasset; Nesvizhskii, Alexey I.; Aebersold, Ruedi; Tenzer, Stefan
2016-01-01
The consistent and accurate quantification of proteins by mass spectrometry (MS)-based proteomics depends on the performance of instruments, acquisition methods and data analysis software. In collaboration with the software developers, we evaluated OpenSWATH, SWATH2.0, Skyline, Spectronaut and DIA-Umpire, five of the most widely used software methods for processing data from SWATH-MS (sequential window acquisition of all theoretical fragment ion spectra), a method that uses data-independent acquisition (DIA) for label-free protein quantification. We analyzed high-complexity test datasets from hybrid proteome samples of defined quantitative composition acquired on two different MS instruments using different SWATH isolation windows setups. For consistent evaluation we developed LFQbench, an R-package to calculate metrics of precision and accuracy in label-free quantitative MS, and report the identification performance, robustness and specificity of each software tool. Our reference datasets enabled developers to improve their software tools. After optimization, all tools provided highly convergent identification and reliable quantification performance, underscoring their robustness for label-free quantitative proteomics. PMID:27701404
A multicenter study benchmarks software tools for label-free proteome quantification.
Navarro, Pedro; Kuharev, Jörg; Gillet, Ludovic C; Bernhardt, Oliver M; MacLean, Brendan; Röst, Hannes L; Tate, Stephen A; Tsou, Chih-Chiang; Reiter, Lukas; Distler, Ute; Rosenberger, George; Perez-Riverol, Yasset; Nesvizhskii, Alexey I; Aebersold, Ruedi; Tenzer, Stefan
2016-11-01
Consistent and accurate quantification of proteins by mass spectrometry (MS)-based proteomics depends on the performance of instruments, acquisition methods and data analysis software. In collaboration with the software developers, we evaluated OpenSWATH, SWATH 2.0, Skyline, Spectronaut and DIA-Umpire, five of the most widely used software methods for processing data from sequential window acquisition of all theoretical fragment-ion spectra (SWATH)-MS, which uses data-independent acquisition (DIA) for label-free protein quantification. We analyzed high-complexity test data sets from hybrid proteome samples of defined quantitative composition acquired on two different MS instruments using different SWATH isolation-window setups. For consistent evaluation, we developed LFQbench, an R package, to calculate metrics of precision and accuracy in label-free quantitative MS and report the identification performance, robustness and specificity of each software tool. Our reference data sets enabled developers to improve their software tools. After optimization, all tools provided highly convergent identification and reliable quantification performance, underscoring their robustness for label-free quantitative proteomics.
Information content in Iris spectra. [Infrared Interferometer Spectrometer of Nimbus 4 satellite
NASA Technical Reports Server (NTRS)
Price, J. C.
1975-01-01
Spectra from the satellite instrument Iris (infrared interferometer spectrometer) were examined to find the number of independent variables needed to describe the broad-band high-resolution spectral data. The radiated power in the atmospheric window from 771 to 981 per cm was the first parameter chosen for fitting observed spectra. At succeeding levels of analysis, the residual variability (observed spectrum minus best-fit spectrum) in an ensemble of observations was partitioned into spectral eigenvectors. The eigenvector describing the largest fraction of this variability was examined for a strong spectral signature; the power in the corresponding spectral band was then used as the next fitting parameter. The measured power in nine spectral intervals, when it was inserted in the spectral-fitting functions, was adequate to describe most spectra to within the noise level of Iris. Considerations of relative signal strength and scales of atmospheric variability suggest a combination sounder (multichannel, broad field of view) scanner (window channel, small field of view) as an efficient observing instrument.
Empirical evidence of the efficiency and efficacy of fat taxes and thin subsidies.
Clark, J Stephen; Dittrich, Ludwig O; Xu, Qin
2014-09-01
This study summarizes the empirical literature on fat taxes and thin subsidies to assess their efficiency and efficacy as instruments of public policy to control obesity. Three specific types of taxes are studied in the literature: food group taxes; nutrient taxes; and nutrient index taxes. Anumber of studies use food expenditure data to assess the impact of various taxes on obesity and therefore only indirectly measure the impacts of taxes and subsidies on obesity. These studies generally conclude that food group taxes, nutrient taxes and nutrient index taxes have a small impact on the purchases of food and the nutrients purchased. Other studies use the body mass index as the explanatory variable and thus measure the impacts of taxes on body mass index directly. Nutrient taxes are found to be more effective than food group taxes, although even for nutrient taxes, the effects are small. In general, thin subsidies seem to offer more effective control of obesity than obesity taxes. However, due to the small effects of both fat taxes and thin subsidies, they are not recommended as instruments of food and nutrition policy.
Recent Greenland Thinning from Operation IceBridge ATM and LVIS Data
NASA Astrophysics Data System (ADS)
Sutterley, T. C.; Velicogna, I.
2015-12-01
We investigate regional thinning rates in Greenland using two Operation IceBridge lidar instruments, the Airborne Topographic Mapper (ATM) and the Land, Vegetation and Ice Sensor (LVIS). IceBridge and Pre-IceBridge ATM data are available from 1993 to present and IceBridge and Pre-Icebridge LVIS data are available from 2007 to present. We compare different techniques for combining the two datasets: overlapping footprints, triangulated irregular network meshing and radial basis functions. We validate the combination for periods with near term overlap of the two instruments. By combining the two lidar datasets, we are able to investigate intra-annual, annual, interannual surface elevation change. We investigate both the high melt season of 2012 and the low melt season of 2013. In addition, the major 2015 IceBridge Arctic campaign provides new crucial data for determining seasonal ice sheet thinning rates. We compare our LVIS/ATM results with surface mass balance outputs from two regional climate models: the Regional Atmospheric Climate Model (RACMO) and the Modèle Atmosphérique Régional (MAR). We also investigate the thinning rates of major outlet glaciers.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Qian, Shi-Bing; Zhang, Wen-Peng; Liu, Wen-Jun
Amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistor (TFT) memory is very promising for transparent and flexible system-on-panel displays; however, electrical erasability has always been a severe challenge for this memory. In this article, we demonstrated successfully an electrically programmable-erasable memory with atomic-layer-deposited Al{sub 2}O{sub 3}/Pt nanocrystals/Al{sub 2}O{sub 3} gate stack under a maximal processing temperature of 300 {sup o}C. As the programming voltage was enhanced from 14 to 19 V for a constant pulse of 0.2 ms, the threshold voltage shift increased significantly from 0.89 to 4.67 V. When the programmed device was subjected to an appropriate pulse under negative gatemore » bias, it could return to the original state with a superior erasing efficiency. The above phenomena could be attributed to Fowler-Nordheim tunnelling of electrons from the IGZO channel to the Pt nanocrystals during programming, and inverse tunnelling of the trapped electrons during erasing. In terms of 0.2-ms programming at 16 V and 350-ms erasing at −17 V, a large memory window of 3.03 V was achieved successfully. Furthermore, the memory exhibited stable repeated programming/erasing (P/E) characteristics and good data retention, i.e., for 2-ms programming at 14 V and 250-ms erasing at −14 V, a memory window of 2.08 V was still maintained after 10{sup 3} P/E cycles, and a memory window of 1.1 V was retained after 10{sup 5} s retention time.« less
NASA Astrophysics Data System (ADS)
Suliyanti, Maria M.; Hidayah, Affi Nur; Kurniawan, K. H.
2012-06-01
Study about thin film production using technique pulsed laser deposition have been done. The Pulsed Laser Deposition (PLD) method has been used for growing thin film of ZrO2 on silicon wafer substrate (111 single crystal, thickness 400μm and diameter 7.5 cm). The target made from Zirconia oxide powder mixing with PVA and press using pressure 100kgN. The laser beam was focused by a lens (f = 100mm) through a quartz window onto the sample surface and the substrate was placed in parallel line with target. The distance between the target and the substrate is about 1 cm. The early results of this synthesis using 75 mJ Nd-YAG second harmonic laser pulse (532 nm Nd-YAG) and low pressure chamber surrounding gas 5 Torr. The irradiation of laser take around 6000 shoots or 10 minutes using frequencies laser 10 Hz. The micro thickness of film can be produced on silicon wafer using this technique. The results of ZrO2 thin film on substrate about 26.92%.
Yu, Jung-Hoon; Nam, Sang-Hun; Lee, Ji Won; Boo, Jin-Hyo
2016-07-09
This paper presents the preparation of high-quality vanadium dioxide (VO₂) thermochromic thin films with enhanced visible transmittance (T vis ) via radio frequency (RF) sputtering and plasma enhanced chemical vapor deposition (PECVD). VO₂ thin films with high T vis and excellent optical switching efficiency (E os ) were successfully prepared by employing SiO₂ as a passivation layer. After SiO₂ deposition, the roughness of the films was decreased 2-fold and a denser structure was formed. These morphological changes corresponded to the results of optical characterization including the haze, reflectance and absorption spectra. In spite of SiO₂ coating, the phase transition temperature (T c ) of the prepared films was not affected. Compared with pristine VO₂, the total layer thickness after SiO₂ coating was 160 nm, which is an increase of 80 nm. Despite the thickness change, the VO₂ thin films showed a higher T vis value (λ 650 nm, 58%) compared with the pristine samples (λ 650 nm, 43%). This enhancement of T vis while maintaining high E os is meaningful for VO₂-based smart window applications.
Temperature Dependent Resistivity and Hall Effect in Proton Irradiated CdS Thin Films
NASA Astrophysics Data System (ADS)
Guster, B.; Ghenescu, V.; Ion, L.; Radu, A.; Porumb, O.; Antohe, S.
2011-10-01
Cadmium sulphide finds extensive applications in a variety of optoelectronic devices. In particular, CdS thin films are suitable for use as windows in heterojunction solar cells that employ CdTe, Cu2S or CuInSe2 as an absorber. Such thin film based solar cells are well suited for use in space technology. For that specific application, it is important to know how ionizing radiations alter their performance. We have investigated the effects of irradiation with high energy protons (3 MeV), at 1014 fluency, on electrical properties of polycrystalline CdS thin layers. The samples were prepared by thermal vacuum deposition from single source onto optical glass substrate. Temperature dependent electrical resistivity and Hall effect, before and after irradiation, were recorded from 300 K down to 4 K. The experimental results can be explained in the frame of a two-band model. Above 100 K electrical properties are controlled by a defect level of donor type, with an ionization energy of about 0.060 eV. The possible origin of this defect is discussed.
Srivastava, Samanvaya; Reddy, P Dinesh Sankar; Wang, Cindy; Bandyopadhyay, Dipankar; Sharma, Ashutosh
2010-05-07
We study by nonlinear simulations the electric field induced pattern formation in a thin viscous film resting on a topographically or chemically patterned substrate. The thin film microstructures can be aligned to the substrate patterns within a window of parameters where the spinodal length scale of the field induced instability is close to the substrate periodicity. We investigate systematically the change in the film morphology and order when (i) the substrate pattern periodicity is varied at a constant film thickness and (ii) the film thickness is varied at a constant substrate periodicity. Simulations show two distinct pathway of evolution when the substrate-topography changes from protrusions to cavities. The isolated substrate defects generate locally ordered ripplelike structures distinct from the structures on a periodically patterned substrate. In the latter case, film morphology is governed by a competition between the pattern periodicity and the length scale of instability. Relating the thin film morphologies to the underlying substrate pattern has implications for field induced patterning and robustness of inter-interface pattern transfer, e.g., coding-decoding of information printed on a substrate.
Adhesion characteristics of VO2 ink film sintered by intense pulsed light for smart window
NASA Astrophysics Data System (ADS)
Youn, Ji Won; Lee, Seok-Jae; Kim, Kwang-Seok; Kim, Dae Up
2018-05-01
Progress in the development of energy-efficient coatings on glass has led to the research of smart windows that can modulate solar energy in response to an external stimulus like light, heat, or electricity. Thermochromic smart windows have attracted great interest because they provide highly visible transparency and intelligently controllable solar heat. VO2 has been widely used as coating material for thermochromism owing to its reversible metal-to-insulator transition near room temperature. However, unstable crystalline phases and expensive fabrication processes of VO2 films limit their facile application in smart windows. To overcome these restrictions, we manufactured nanoinks based on VO2 nanoparticles and fabricated films using spin coating and intense pulsed light (IPL) sintering on a quartz substrate. We examined adhesion between the VO2 nanoink films and the quartz substrate by varying the applied voltages and the number of pulses. The average adhesion of thin films increased to 83 and 108 N/m as the applied voltage during IPL sintering increased from 1400 to 2000 V. By increasing the number of pulses from 5 to 20, the adhesive strength increased from 83 to 94 N/m at 1400 V, and decreased from 108 to 96 N/m at 2000 V voltage.
76 FR 20952 - Application(s) for Duty-Free Entry of Scientific Instruments
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-14
.... Intended Use: The instrument will be used to identify and characterize new viruses, bacteria, fungi... other experiments including cell culture morphology, transplant and host tissue interactions, and... of thin surfaces such as silica, silicon nitride or silicon carbide materials. Experiments will be...
Multiphoton Intravital Calcium Imaging.
Cheetham, Claire E J
2018-06-26
Multiphoton intravital calcium imaging is a powerful technique that enables high-resolution longitudinal monitoring of cellular and subcellular activity hundreds of microns deep in the living organism. This unit addresses the application of 2-photon microscopy to imaging of genetically encoded calcium indicators (GECIs) in the mouse brain. The protocols in this unit enable real-time intravital imaging of intracellular calcium concentration simultaneously in hundreds of neurons, or at the resolution of single synapses, as mice respond to sensory stimuli or perform behavioral tasks. Protocols are presented for implantation of a cranial imaging window to provide optical access to the brain and for 2-photon image acquisition. Protocols for implantation of both open skull and thinned skull windows for single or multi-session imaging are described. © 2018 by John Wiley & Sons, Inc. © 2018 John Wiley & Sons, Inc.
Diamondlike carbon protective coatings for optical windows
NASA Technical Reports Server (NTRS)
Swec, Diane M.; Mirtich, Michael J.
1989-01-01
Diamondlike carbon (DLC) films were deposited on infrared transmitting optical windows and were evaluated as protective coatings for these windows exposed to particle and rain erosion. The DLC films were deposited on zinc selenide (ZnSe) and zinc sulfide (ZnS) by three different ion beam methods: (1) sputter deposition from a carbon target using an 8-cm argon ion source; (2) direct deposition by a 30-cm hollow cathode ion source with hydrocarbon gas in argon; and (3) dual beam direct deposition by the 30-cm hollow cathode ion source and an 8-cm argon ion source. In an attempt to improve the adherence of the DLC films on ZnSc and ZnS, ion beam cleaning, ion implantation with helium and neon ions, or sputter deposition of a thin, ion beam intermediate coating was employed prior to deposition of the DLC film. The protection that the DLC films afforded the windows from particle and rain erosion was evaluated, along with the hydrogen content, adherence, intrinsic stress, and infrared transmittance of the films. Because of the elevated stress levels in the ion beam sputtered DLC films and in those ion beam deposited with butane, films thicker than 0.1 micron and with good adherence on ZnS and ZnSe could not be generated. An intermediate coating of germanium successfully allowed the DLC films to remain adherent to the optical windows and caused only negligible reduction in the specular transmittance of the ZnS and ZnSe at 10 microns.
NASA Technical Reports Server (NTRS)
Kratz, David P.; Priestley, Kory J.; Green, Richard N.
1999-01-01
Observing Earth s radiant energy budget from space is critical to improving our understanding of Earth s climate system. The Earth Radiation Budget Experiment (ERBE) was the first initiative to provide simultaneous observations of Earth s radiant energy with identical instruments flying aboard separate satellites. The design of the ERBE instrument was based upon three complementary broadband radiometers which measured the shortwave (< 5 mm), longwave (> 5 mm), and total regions of the spectrum. Since any two of the ERBE radiometers could be used to simulate the third, a three channel intercomparison, based on redundancy, was available to uncover any changes in the relative sensitivities of the individual radiometers. Such a three channel intercomparison thus provided confidence in the application of the ERBE measurements over the lifetime of the instrument while mitigating the concern over instrument degradation.
NASA Technical Reports Server (NTRS)
Ioup, George E.; Ioup, Juliette W.
1989-01-01
The power spectrum for a stationary random process can be defined with the Wiener-Khintchine Theorem, which says that the power spectrum and the auto correlation function are a Fourier transform pair. To implement this theorem for signals that are discrete and of finite length we can use the Blackman-Tukey method. Blackman and Tukey (1958) show that a function w(tau), called a lag window, can be applied to the auto correlation estimates to obtain power spectrum estimates that are statistically stable. The Fourier transform of w(r) is called a spectral window. Typical choices for spectral windows show a distinct trade-off between the main lobe width and side lobe strength. A new idea for designing windows by taking linear combinations of the standard windows to produce hybrid windows was introduced by Smith (1985). We implement Smith's idea to obtain spectral windows with narrow main lobes and smaller (compared with typical windows) near side lobes. One of the main contributions of this thesis is that we show that Smith's problem is equivalent to a Quadratic Programming (QP) problem with linear equality and inequality constraints. A computer program was written to produce hybrid windows by setting up and solving the QP problem. We also developed and solved two variations of the original problem. The two variations involved changing the inequality constraints in both cases from non negativity on the combination coefficients to non negativity on the hybrid lag window itself. For the second variation, the window functions used to construct the hybrid window were changed to a frequency-variable set of truncated cosinusoids. A series of tests was run with the three computer programs to investigate the behavior of the hybrid spectral and lag windows. Emphasis was put on obtaining spectral windows with both relatively narrow main lobes and the lowest possible (for these algorithms) near side lobes. Some success was achieved for this goal. A 10 dB peak side lobe reduction over the rectangular spectral window without significant main lobe broadening was achieved. Also, average side lobe levels of -117 dB were reached at a cost of doubling the main lobe width (at the -3 dB point).
Assessing Server Fault Tolerance and Disaster Recovery Implementation in Thin Client Architectures
2007-09-01
server • Windows 2003 server Processor AMD Geode GX Memory 512MB Flash/256MB DDR RAM I/O/Peripheral Support • VGA-type video output (DB-15...2000 Advanced Server Processor AMD Geode NX 1500 Memory • 256MB or 512MB or 1GB DDR SDRAM • 1GB or 512MB Flash I/O/Peripheral Support • SiS741 GX
Advanced Waveform Simulation for Seismic Monitoring
2008-09-01
velocity model. The method separates the main arrivals of the regional waveform into 5 windows: Pnl (vertical and radial components), Rayleigh (vertical and...ranges out to 10°, including extensive observations of crustal thinning and thickening and various Pnl complexities. Broadband modeling in 1D, 2D...existing models perform in predicting the various regional phases, Rayleigh waves, Love waves, and Pnl waves. Previous events from this Basin-and-Range
NASA Astrophysics Data System (ADS)
Quarles, C. A.; Portillo, S.
1999-06-01
Calculations of the total bremsstrahlung spectrum including polarization bremsstrahlung (PB) for high energy electrons on atoms have been made recently by A. V. Korol, A. G. Lyalin and A. V. Solovy'ov. This has motivated us to look for the PB effect for 25 and 50 keV electrons on a variety of thin-film targets including C, Al, Cu, Ag, Tb and Au. PB is predicted to be a significant increase in radiated photon intensity at energies below the target K and L absorption edges. A good model of the thick-target bremsstrahlung background due to electrons elastically scattered into the detector window and a good understanding of the Ge and Si(Li) detector response are crucial for interpretation of the data. We have used a geometry in which the detector-window background is significantly reduced from that in prior experiments. We have analyzed the photon spectra from above 4 keV to the kinematic endpoint. The data are very well fit by normal bremsstrahlung alone. No PB contribution is seen in the data. Finally, we conclude with an argument why, in fact, we should not expect any PB effect when charged particles interact with solid film targets.
Patterning of organic photovoltaic on R2R processed thin film barriers using IR laser sources
NASA Astrophysics Data System (ADS)
Fledderus, H.; Akkerman, H. B.; Salem, A.; Friedrich Schilling, N.; Klotzbach, U.
2017-02-01
We present the development of laser processes for flexible OPV on roll-to-roll (RR2R) produced thin film barrier with indium tin oxide (ITO) as transparent conductive (TC) bottom electrode. Direct laser structuring of ITO on such barrier films (so-called P1 process) is very challenging since the layers are all transparent, a complete electrical isolation is required, and the laser process should not influence the barrier performance underneath the scribes. Based on the optical properties off the SiN and ITTO, ultra-short pulse lasers inn picosecond and femtosecond regime with standard infrared (IR) wavelength as well as lasers with new a wavelength (22 μm regime) are tested for this purpose. To determine a process window for a specific laser a fixed methodology is adopted. Single pulse ablation tests were followed by scribing experiments where the pulse overlap was tuned by varying laser pulse fluence, writing speed and frequency. To verify that the laser scribing does not result inn barrier damage underneath, a new test method was developed based on the optical Ca-test. This method shows a clear improvement in damage analysis underneath laser scribes over normal optical inspection methods (e.g. microscope, optical profiler, SEM). This way clear process windows can be obtained for IR TC patterning.
NASA Astrophysics Data System (ADS)
Jeon, Raymond J.; Mandelis, Andreas; Abrams, Stephen H.
2003-01-01
Simultaneous measurements from human teeth of photothermal radiometric (PTR) and luminescence (LM) signals induced by an intensity modulated laser have been performed to assess the feasibility of detecting deep lesions and near-surface cracks, to examine the effects of varying enamel thicknesses, the presence of fillings, and stains on the surface of teeth. A commercial dc luminescence monitoring instrument (DIAGNOdent by KaVo) was also used to examine a set of teeth for comparison purposes with PTR and LM. PTR amplitude signals from carious regions and from thin enamel were higher than those from healthy regions and thicker enamel. A crack produces a peak in the PTR amplitude scan, as well as a sudden change in the luminescence amplitude at the corresponding point. At low frequencies (5 Hz), the PTR amplitude showed high sensitivity to a deep (about 2 mm) lesion, while at high frequencies (700 Hz) it was more sensitive to surface cracks. It was concluded that by selecting proper modulation frequencies of the laser, measurements of PTR and LM signals could be used as a dental diagnostic technique with a small, inexpensive, low-power (<30 mW) semiconductor laser as a light source emitting in the optical window range of hard tissue (650-1000 nm).
ERIC Educational Resources Information Center
Reynolds, Ronald F.
1984-01-01
Describes the basic components of a space telescope that will be launched during a 1986 space shuttle mission. These components include a wide field/planetary camera, faint object spectroscope, high-resolution spectrograph, high-speed photometer, faint object camera, and fine guidance sensors. Data to be collected from these instruments are…
Optical instruments synergy in determination of optical depth of thin clouds
NASA Astrophysics Data System (ADS)
Viviana Vlăduţescu, Daniela; Schwartz, Stephen E.; Huang, Dong
2018-04-01
Optically thin clouds have a strong radiative effect and need to be represented accurately in climate models. Cloud optical depth of thin clouds was retrieved using high resolution digital photography, lidar, and a radiative transfer model. The Doppler Lidar was operated at 1.5 μm, minimizing return from Rayleigh scattering, emphasizing return from aerosols and clouds. This approach examined cloud structure on scales 3 to 5 orders of magnitude finer than satellite products, opening new avenues for examination of cloud structure and evolution.
Optical Instruments Synergy in Determination of Optical Depth of Thin Clouds
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vladutescu, Daniela V.; Schwartz, Stephen E.
Optically thin clouds have a strong radiative effect and need to be represented accurately in climate models. Cloud optical depth of thin clouds was retrieved using high resolution digital photography, lidar, and a radiative transfer model. The Doppler Lidar was operated at 1.5 μm, minimizing return from Rayleigh scattering, emphasizing return from aerosols and clouds. This approach examined cloud structure on scales 3 to 5 orders of magnitude finer than satellite products, opening new avenues for examination of cloud structure and evolution.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abayli, D., E-mail: abayli@itu.edu.tr; Baydogan, N., E-mail: dogannil@itu.edu.tr
In this study, zirconium oxide (ZrO{sub 2}) thin film samples prepared by sol–gel method were irradiated using Co-60 radioisotope as gamma source. Then, it was investigated the ionizing effect on optical properties of ZrO{sub 2} thin film samples with the rise of the absorbed dose. The changes in the optical absorbance of ZrO{sub 2} thin films were determined by using optical transmittance and the reflectance measurements in the range between 190 – 1100 nm obtained from PG Instruments T80 UV-Vis spectrophotometer.
NASA Astrophysics Data System (ADS)
Nuzzo, L.; Calia, A.; Liberatore, D.; Masini, N.; Rizzo, E.
2010-04-01
The integration of high-resolution, non-invasive geophysical techniques (such as ground-penetrating radar or GPR) with emerging sensing techniques (acoustics, thermography) can complement limited destructive tests to provide a suitable methodology for a multi-scale assessment of the state of preservation, material and construction components of monuments. This paper presents the results of the application of GPR, infrared thermography (IRT) and ultrasonic tests to the 13th century rose window of Troia Cathedral (Apulia, Italy), affected by widespread decay and instability problems caused by the 1731 earthquake and reactivated by recent seismic activity. This integrated approach provided a wide amount of complementary information at different scales, ranging from the sub-centimetre size of the metallic joints between the various architectural elements, narrow fractures and thin mortar fillings, up to the sub-metre scale of the internal masonry structure of the circular ashlar curb linking the rose window to the façade, which was essential to understand the original building technique and to design an effective restoration strategy.
NASA Technical Reports Server (NTRS)
Yost, William T.; Cramer, K. Elliott; Estes, Linda R.; Salem, Jonathan A.; Lankford, James, Jr.; Lesniak, Jon
2011-01-01
A commercially available grey-field polariscope (GFP) instrument for photoelastic examination is used to assess impact damage inflicted upon the outermost pane of the orbiter windows. Four categories of damage: hyper-velocity impacts that occur during space-flight (HVI); hypervelocity impacts artificially made at the Hypervelocity Impact Technology Facility (HIT-F); impacts made by larger objects falling onto the pane surface to simulate dropped items on the window during service/storage of vehicle (Bruises); and light scratches from dull objects designed to mimic those that might occur by dragging a dull object across the glass surface (Chatter Checks) are examined. The damage sites are cored from fused silica window carcasses, examined with the GFP and other methodologies, and broken using the ASTM Standard C1499-09 to measure the fracture strength. A correlation is made between the fracture strength and damage-site measurements including geometrical measurements and GFP measurements of photoelastic retardation (stress patterns) surrounding the damage sites. An analytical damage model to predict fracture strength from photoelastic retardation measurements is presented and compared with experimental results.
NASA Astrophysics Data System (ADS)
Pintér, Balázs; Erdélyi, R.
2018-01-01
Solar fundamental (f) acoustic mode oscillations are investigated analytically in a magnetohydrodynamic (MHD) model. The model consists of three layers in planar geometry, representing the solar interior, the magnetic atmosphere, and a transitional layer sandwiched between them. Since we focus on the fundamental mode here, we assume the plasma is incompressible. A horizontal, canopy-like, magnetic field is introduced to the atmosphere, in which degenerated slow MHD waves can exist. The global (f-mode) oscillations can couple to local atmospheric Alfvén waves, resulting, e.g., in a frequency shift of the oscillations. The dispersion relation of the global oscillation mode is derived, and is solved analytically for the thin-transitional layer approximation and for the weak-field approximation. Analytical formulae are also provided for the frequency shifts due to the presence of a thin transitional layer and a weak atmospheric magnetic field. The analytical results generally indicate that, compared to the fundamental value (ω =√{ gk }), the mode frequency is reduced by the presence of an atmosphere by a few per cent. A thin transitional layer reduces the eigen-frequencies further by about an additional hundred microhertz. Finally, a weak atmospheric magnetic field can slightly, by a few percent, increase the frequency of the eigen-mode. Stronger magnetic fields, however, can increase the f-mode frequency by even up to ten per cent, which cannot be seen in observed data. The presence of a magnetic atmosphere in the three-layer model also introduces non-permitted propagation windows in the frequency spectrum; here, f-mode oscillations cannot exist with certain values of the harmonic degree. The eigen-frequencies can be sensitive to the background physical parameters, such as an atmospheric density scale-height or the rate of the plasma density drop at the photosphere. Such information, if ever observed with high-resolution instrumentation and inverted, could help to gain further insight into solar magnetic structures by means of solar magneto-seismology, and could provide further insight into the role of magnetism in solar oscillations.
Telescience capability for the Sondre Stromfjord, Greenland, incoherent-scatter radar facility
NASA Astrophysics Data System (ADS)
Zambre, Yadunath B.
1993-01-01
SRI International (SRI) operates an upper-atmospheric research facility in Sondre Stromfjord (Sondrestrom), Greenland. In the past, the facility's remote location and limited logistical support imposed constraints on the research that could be carried out at the site. Campaigns involving multiple instruments were often constrained due to limited space, and experiments requiring coordination with other geographically separated facilities, though possible, were difficult. To provide greater access to the facility, an electronic connection between Sondrestrom and the mainland U.S.A. was established, providing access to the National Science Internet. SRI developed telescience software that sends data from the incoherent scatter radar at the Sondrestrom facility to SRI's offices in Menlo Park, California. This software uses the transmission control protocol (TCP/IP) to transmit the data in near real time between the two locations and the X window system to generate displays of the data in Menlo Park. This is in contrast to using the X window system to display data remotely across a wide-area network. Using CP to transport data over the long distance network has resulted in significantly improved network throughput and latency. While currently used to transport radar data, the telescience software is designed and intended for simultaneous use with other instruments at Sondrestrom and other facilities. Work incorporating additional instruments is currently in progress.
OCTOCAM: A Workhorse Instrument for the Gemini Telescopes During the Era of LSST
NASA Astrophysics Data System (ADS)
Roming, Peter; van der Horst, Alexander; OCTOCAM Team
2018-01-01
The decade of the 2020s are planned to be an era of large surveys and giant telescopes. A trademark of this era will be the large number of interesting objects observed daily by high-cadence surveys, such as the LSST. Because of the sheer numbers, only a very small fraction of these interesting objects will be observed with extremely large telescopes. The follow up workhorses during this era will be the 8-meter class telescopes and corresponding instruments that are prepared to pursue these interesting objects. One such workhorse instrument is OCTOCAM, a highly efficient instrument designed to probe the time domain window with simulatenous broad-wavelength coverage. OCTOCAM optimizes the use of Gemini for broadband imaging and spectroscopic single-target observations. The instrument is designed for high temporal resolution, broad spectral coverage, and moderate spectral resolution. OCTOCAM was selected as part of the Gemini instrumentation program in early 2017. Here we provide a description of the science cases to be addressed, overall instrument design, and current status.
Homogeneous-oxide stack in IGZO thin-film transistors for multi-level-cell NAND memory application
NASA Astrophysics Data System (ADS)
Ji, Hao; Wei, Yehui; Zhang, Xinlei; Jiang, Ran
2017-11-01
A nonvolatile charge-trap-flash memory that is based on amorphous indium-gallium-zinc-oxide thin film transistors was fabricated with a homogeneous-oxide structure for a multi-level-cell application. All oxide layers, i.e., tunneling layer, charge trapping layer, and blocking layer, were fabricated with Al2O3 films. The fabrication condition (including temperature and deposition method) of the charge trapping layer was different from those of the other oxide layers. This device demonstrated a considerable large memory window of 4 V between the states fully erased and programmed with the operation voltage less than 14 V. This kind of device shows a good prospect for multi-level-cell memory applications.
Structure and enhanced thermochromic performance of low-temperature fabricated VO2/V2O3 thin film
NASA Astrophysics Data System (ADS)
Sun, Guangyao; Cao, Xun; Gao, Xiang; Long, Shiwei; Liang, Mengshi; Jin, Ping
2016-10-01
For VO2-based smart window manufacture, it is a long-standing demand for high-quality thin films deposited at low temperature. Here, the thermochromic films of VO2 were deposited by a magnetron sputtering method at a fairly low temperature of 250 °C without subsequent annealing by embedding a V2O3 interlayer. V2O3 acts as a seed layer to lower the depositing temperature and buffer layer to epitaxial grow VO2 film. The VO2/V2O3 films display high solar modulating ability and narrow hysteresis loop. Our data can serve as a promising point for industrial production with high degree of crystallinity at a low temperature.
Cell micro-irradiation with MeV protons counted by an ultra-thin diamond membrane
NASA Astrophysics Data System (ADS)
Barberet, Philippe; Pomorski, Michal; Muggiolu, Giovanna; Torfeh, Eva; Claverie, Gérard; Huss, Cédric; Saada, Samuel; Devès, Guillaume; Simon, Marina; Seznec, Hervé
2017-12-01
We report the development of thin single crystal diamond membranes suitable for dose control in targeted cell irradiation experiments with a proton microbeam. A specific design was achieved to deliver single protons with a hit detection efficiency approaching 100%. The membranes have thicknesses between 1.8 and 3 μm and are used as vacuum windows on the microbeam line. The impact of these transmission detectors on the microbeam spot size is estimated by Monte-Carlo simulations, indicating that a beam lateral resolution below 2 μm is achieved. This is confirmed by experiments showing the accumulation online of X-ray Repair Cross-Complementing protein 1 (XRCC1)-Green Fluorescent Protein (GFP) at DNA damaged sites in living cells.
Grating-assisted coupling to nanophotonic circuits in microcrystalline diamond thin films.
Rath, Patrik; Khasminskaya, Svetlana; Nebel, Christoph; Wild, Christoph; Pernice, Wolfram Hp
2013-01-01
Synthetic diamond films can be prepared on a waferscale by using chemical vapour deposition (CVD) on suitable substrates such as silicon or silicon dioxide. While such films find a wealth of applications in thermal management, in X-ray and terahertz window design, and in gyrotron tubes and microwave transmission lines, their use for nanoscale optical components remains largely unexplored. Here we demonstrate that CVD diamond provides a high-quality template for realizing nanophotonic integrated optical circuits. Using efficient grating coupling devices prepared from partially etched diamond thin films, we investigate millimetre-sized optical circuits and achieve single-mode waveguiding at telecoms wavelengths. Our results pave the way towards broadband optical applications for sensing in harsh environments and visible photonic devices.
The Gaertner L119 ellipsometer and its use in the measurement of thin films
NASA Technical Reports Server (NTRS)
Linkous, M.
1973-01-01
An introduction to the study of ellipsometry is presented, with special attention given to the Gaertner model L119 ellipsometer and the techniques of measuring thin films with this instrument. Values obtained from the ellipsometer are analyzed by a computer program for a determination of optical constants and thickness of the film.
NASA Technical Reports Server (NTRS)
2003-01-01
January 28, 2003The Mars Exploration Rover -2 is moved to a workstand in the Payload Hazardous Servicing Facility. Set to launch in 2003, the Mars. Exploration Rover Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, 2003, and the second rover a window opening June 25, 2003.2003-04-25
KENNEDY SPACE CENTER, FLA. - Workers in the Payload Hazardous Servicing Facility help guide the Mars Exploration Rover 1 (MER-1) as it is moved to the lander base petal for installation. The MER Mission consists of two identical rovers, landing at different regions of Mars, designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The first rover has a launch window opening June 5, and the second rover a window opening June 25. The rovers will be launched from Cape Canaveral Air Force Station.
2003-04-04
KENNEDY SPACE CENTER, FLA. - Workers in the Payload Hazardous Servicing Facility examine the Mars Exploration Rover 2 (MER-2) as it is lowered onto the base petal of the lander. Set to launch in Spring 2003, the MER Mission consists of two identical rovers. Landing at different regions of Mars, they are designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-04-25
KENNEDY SPACE CENTER, FLA. - Workers in the Payload Hazardous Servicing Facility guide the Mars Exploration Rover 1 (MER-1) as it is lowered onto the lander base petal for installation. The MER Mission consists of two identical rovers, landing at different regions of Mars, designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The first rover has a launch window opening June 5, and the second rover a window opening June 25. The rovers will be launched from Cape Canaveral Air Force Station.
2003-04-04
KENNEDY SPACE CENTER, FLA. - Workers in the Payload Hazardous Servicing Facility check the Mars Exploration Rover 2 (MER-2) before it is lifted and moved to the lander where it will be mated to the base petal. Set to launch in Spring 2003, the MER Mission consists of two identical rovers, landing at different regions of Mars, designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-04-25
KENNEDY SPACE CENTER, FLA. - Workers in the Payload Hazardous Servicing Facility guide the Mars Exploration Rover 1 (MER-1) as it is lowered onto the lander base petal for installation. The MER Mission consists of two identical rovers, landing at different regions of Mars, designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The first rover has a launch window opening June 5, and the second rover a window opening June 25. The rovers will be launched from Cape Canaveral Air Force Station.
2003-04-04
KENNEDY SPACE CENTER, FLA. - Workers in the Payload Hazardous Servicing Facility release the overhead crane used to lower the Mars Exploration Rover 2 (MER-2) onto the base petal of the lander. Set to launch in Spring 2003, the MER Mission consists of two identical rovers. Landing at different regions of Mars, they are designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
NASA Technical Reports Server (NTRS)
2003-01-01
January 31, 2003In the Payload Hazardous Servicing Facility, an overhead crane lowers the Mars Exploration Rover (MER) aeroshell toward a rotation stand. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.2003-03-20
KENNEDY SPACE CENTER, Fla. - The solar arrays on the Mars Exploration Rover-2 (MER-2) are fully opened during a test in the Payload Hazardous Servicing Facility. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-04-02
KENNEDY SPACE CENTER, FLA. - The Mars Exploration Rover 1 (MER-1) is seen in the foreground after the science boom was deployed. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-01-28
KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, workers lift the cover from the Mars Exploration Rover -2. Set to launch in 2003, the Mars Exploration Rover Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, 2003, and the second rover a window opening June 25, 2003.
2003-03-29
KENNEDY SPACE CENTER, FLA. - Workers gather around the Mars Exploration Rover 2 (MER-2) before flight stow of the solar panels, still extended. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. The rovers will be identical to each other, but will land at different regions of Mars. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-01-31
KENNEDY SPACE CENTER, FLA. -- In the Payload Hazardous Servicing Facility, an overhead crane lifts the Mars Exploration Rover (MER) aeroshell for transfer to a rotation stand. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-03-29
KENNEDY SPACE CENTER, FLA. - Workers begin closing the solar panels on the Mars Exploration Rover 2 (MER-2) for flight stow. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. The rovers will be identical to each other, but will land at different regions of Mars. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-02-04
KENNEDY SPACE CENTER, FLA. -- The aeroshell for Mars Exploration Rover 2 rests on a rotation stand in the Payload Hazardous Servicing Facility. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-01-31
KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, the Mars Exploration Rover (MER) aeroshell is being prepared for transfer to a rotation stand. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-03-20
KENNEDY SPACE CENTER, FLA. -- The Mars Exploration Rover-2 (MER-2) is ready for solar array testing in the Payload Hazardous Servicing Facility. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-03-21
KENNEDY SPACE CENTER, Fla. - In the Payload Hazardous Servicing Facility, the Mars Exploration Rover-2 (MER-2) is tested for mobility and maneuverability. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-03-29
KENNEDY SPACE CENTER, FLA. - A worker makes the final launch preparations on the rover equipment deck (RED) for the Mars Exploration Rover 2 (MER-2). Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. The rovers will be identical to each other, but will land at different regions of Mars. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-01-31
KENNEDY SPACE CENTER, FLA. -- In the Payload Hazardous Servicing Facility, an overhead crane lowers the Mars Exploration Rover (MER) aeroshell toward a rotation stand. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-02-06
KENNEDY SPACE CENTER, FLA. -- Technicians secure the aeroshell for Mars Exploration Rover 2 to a workstand in the Payload Hazardous Servicing Facility. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover, a window opening June 25, 2003.
2003-02-04
KENNEDY SPACE CENTER, FLA. -- The aeroshell for Mars Exploration Rover 2 rests on end after rotation in the Payload Hazardous Servicing Facility. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
Mars Exploration Rover (MER) aeroshell
2003-01-31
In the Payload Hazardous Servicing Facility, workers prepare the Mars Exploration Rover (MER) aeroshell for transfer to a rotation stand. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-01-28
KENNEDY SPACE CENTER, FLA. -- The Mars Exploration Rover -2 is moved to a workstand in the Payload Hazardous Servicing Facility. Set to launch in 2003, the Mars Exploration Rover Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, 2003, and the second rover a window opening June 25, 2003.
2003-01-31
KENNEDY SPACE CENTER, FLA. -- Workers in the Payload Hazardous Servicing Facility help guide the Mars Exploration Rover (MER) aeroshell onto a rotation stand. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-01-31
KENNEDY SPACE CENTER, FLA. - Workers in the Payload Hazardous Servicing Facility help guide the Mars Exploration Rover (MER) aeroshell as it is lowered toward a rotation stand. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-01-28
KENNEDY SPACE CENTER, FLA. -- In the Payload Hazardous Servicing Facility, workers get ready to remove the plastic covering from the Mars Exploration Rover -2. Set to launch in 2003, the Mars Exploration Rover Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, 2003, and the second rover a window opening June 25, 2003.
2003-02-04
KENNEDY SPACE CENTER, FLA. - During processing, workers in the Payload Hazardous Servicing Facility work on part of the aeroshell for Mars Exploration Rover 2. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-03-21
KENNEDY SPACE CENTER, Fla. - Workers in the Payload Hazardous Servicing Facility check different parts of the Mars Exploration Rover-2 (MER-2) after testing the rover's mobility and maneuverability. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-04-02
KENNEDY SPACE CENTER, FLA. - A worker examines the Mars Exploration Rover 1 (MER-1) after the science boom was deployed. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-03-29
KENNEDY SPACE CENTER, FLA. - A worker checks a component of the Mars Exploration Rover 2 (MER-2) before flight stow of the solar panels, still extended. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. The rovers will be identical to each other, but will land at different regions of Mars. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-03-28
KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, the Mars Exploration Rover-2 (MER-2) rests on the base petal of its lander assembly. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover, a window opening June 25.
2003-04-02
KENNEDY SPACE CENTER, FLA. - On the Mars Exploration Rover 1 (MER-1), the science boom, below the front petal, is deployed. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-03-29
KENNEDY SPACE CENTER, FLA. - Workers make additional checks of the Mars Exploration Rover 2 (MER-2) before flight stow of the solar panels, still extended. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. The rovers will be identical to each other, but will land at different regions of Mars. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-01-28
KENNEDY SPACE CENTER, FLA. - Workers in the Payload Hazardous Servicing Facility move the Mars Exploration Rover -2 to a workstand in the high bay. Set to launch in 2003, the Mars Exploration Rover Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, 2003, and the second rover a window opening June 25, 2003.
2003-03-21
KENNEDY SPACE CENTER, Fla. - In the Payload Hazardous Servicing Facility, the Mars Exploration Rover-2 (MER-2) rolls over ramps to test its mobility and maneuverability. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-03-29
KENNEDY SPACE CENTER, FLA. - After closing the solar panels for flight stow, workers examine the Mars Exploration Rover 2 (MER-2). Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. The rovers will be identical to each other, but will land at different regions of Mars. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
Thickness and microstructure effects in the optical and electrical properties of silver thin films
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ding, Guowen, E-mail: gding@intermolecular.com; Clavero, César; Schweigert, Daniel
The optical and electrical response of metal thin films approaching thicknesses in the range of the electron mean free path is highly affected by electronic scattering with the interfaces and defects. Here, we present a theoretical and experimental study on how thickness and microstructure affect the properties of Ag thin films. We are able to successfully model the electrical resistivity and IR optical response using a thickness dependent electronic scattering time. Remarkably, the product of electronic scattering time and resistivity remains constant regardless of the thickness (τx ρ = C), with a value of 59 ± 2 μΩ cm ⋅more » fs for Ag films in the investigated range from 3 to 74 nm. Our findings enable us to develop a theoretically framework that allows calculating the optical response of metal thin films in the IR by using their measured thickness and resistivity. An excellent agreement is found between experimental measurements and predicted values. This study also shows the theoretical lower limit for emissivity in Ag thin films according to their microstructure and thickness. Application of the model presented here will allow rapid characterization of the IR optical response of metal thin films, with important application in a broad spectrum of fundamental and industrial applications, including optical coatings, low-emissivity windows and semiconductor industry.« less
NASA Astrophysics Data System (ADS)
De Breuck, Carlos
2018-03-01
The APEX telescope has a range instruments that are highly complementary to ALMA. The single pixel heterodyne receivers cover virtually all atmospheric windows from 157 GHz to above 1 THz, augmented by 7-pixel heterodyne arrays covering 280 to 950 GHz, while the bolometer arrays cover the 870, 450 and 350µm bands.
Advances in EPG for Treatment and Research: An Illustrative Case Study
ERIC Educational Resources Information Center
Scobbie, James M.; Wood, Sara E.; Wrench, Alan A.
2004-01-01
Electropalatography (EPG), a technique which reveals tongue-palate contact patterns over time, is a highly effective tool for speech research. We report here on recent developments by Articulate Instruments Ltd. These include hardware for Windows-based computers, backwardly compatible (with Reading EPG3) software systems for clinical intervention…
NASA Astrophysics Data System (ADS)
Freissinet, C.; Glavin, D. P.; Mahaffy, P. R.; Szopa, C.; Buch, A.; Goesmann, F.; Goetz, W.; Raulin, F.; SAM Science Team; MOMA Science Team
2018-04-01
SAM (Curiosity) and MOMA (ExoMars) Mars instruments, seeking for organics and biosignatures, are essential to establish taphonomic windows of preservation of molecules, in order to target the most interesting samples to return from Mars.
NASA Astrophysics Data System (ADS)
Han, Jin-Hee
2018-03-01
Recently the aspect ratio of capacitor and via hole of memory semiconductor device has been dramatically increasing in order to store more information in a limited area. A small amount of remained residues after etch process on the bottom of the high aspect ratio structure can make a critical failure in device operation. Back-scattered electrons (BSE) are mainly used for inspecting the defect located at the bottom of the high aspect ratio structure or analyzing the overlay of the multi-layer structure because these electrons have a high linearity with the direction of emission and a high kinetic energy above 50eV. However, there is a limitation on that it cannot detect ultra-thin residue material having a thickness of several nanometers because the surface sensitivity is extremely low. We studied the characteristics of BSE spectra using Monte Carlo simulations for several cases which the high aspect ratio structures have extreme microscopic residues. Based on the assumption that most of the electrons emitted without energy loss are localized on the surface, we selected the detection energy window which has a range of 20eV below the maximum energy of the BSE. This window section is named as the high-energy BSE region. As a result of comparing the detection sensitivity of the conventional and the high-energy BSE detection mode, we found that the detection sensitivity for the residuals which have 2nm thickness is improved by more than 10 times in the high-energy BSE mode. This BSE technology is a new inspection method that can greatly be improved the inspection sensitivity for the ultra-thin residual material presented in the high aspect ratio structure, and its application will be expanded.
NASA Technical Reports Server (NTRS)
Lupton, W. F.; Conrad, A. R.
1992-01-01
KTL is a set of routines which eases the job of writing applications which must interact with a variety of underlying sub-systems (known as services). A typical application is an X Window user interface coordinating telescope and instruments. In order to connect to a service, application code specifies a service name--typically an instrument name--and a style, which defines the way in which the application will interact with the service. Two styles are currently supported: keyword, where the application reads and writes named keywords and the resulting inter-task message traffic is hidden; and message, where the application deals directly with messages. The keyword style is intended mainly for user interfaces, and the message style is intended mainly for lower-level applications. KTL applications are event driven: a typical application first connects to all its desired services, then expresses interest in specified events. The application then enters an event dispatch loop in which it waits for events and calls the appropriate service's event-handling routine. Each event is associated with a call-back routine which is invoked when the event occurs. Call-back routines may (and typically do) interact with other sub-systems and KTL provides the means of doing so without blocking the application (vital for X Window user interfaces). This approach is a marriage of ideas culled from the X window, ADAM, Keck instrument, and Keck telescope control systems. A novel feature of KTL is that it knows nothing about any services or styles. Instead it defines a generic set of routines which must be implemented by all services and styles (essentially open(), ioctl(), read(), write(), event(), and close()) and activates sharable libraries at run-time. Services have been implemented (in both keyword and message styles) for HIRES (the Keck high resolution echelle spectrograph built by Lick Observatory), LWS (the Keck long wavelength spectrometer built by UC San Diego), and the Keck telescope. Each of these implementations uses different underlying message systems: the Lick MUSIC system, RPC's, and direct sockets (respectively). Services for the remaining three front-line Keck instruments will be implemented over the next few months.
Radioactive sample effects on EDXRF spectra
DOE Office of Scientific and Technical Information (OSTI.GOV)
Worley, Christopher G
2008-01-01
Energy dispersive X-ray fluorescence (EDXRF) is a rapid, straightforward method to determine sample elemental composition. A spectrum can be collected in a few minutes or less, and elemental content can be determined easily if there is adequate energy resolution. Radioactive alpha emitters, however, emit X-rays during the alpha decay process that complicate spectral interpretation. This is particularly noticeable when using a portable instrument where the detector is located in close proximity to the instrument analysis window held against the sample. A portable EDXRF instrument was used to collect spectra from specimens containing plutonium-239 (a moderate alpha emitter) and americium-241 (amore » heavy alpha emitter). These specimens were then analyzed with a wavelength dispersive XRF (WDXRF) instrument to demonstrate the differences to which sample radiation-induced X-ray emission affects the detectors on these two types of XRF instruments.« less
Rawlence, M; Filippin, A N; Wäckerlin, A; Lin, T-Y; Cuervo-Reyes, E; Remhof, A; Battaglia, C; Rupp, J L M; Buecheler, S
2018-04-25
Replacing the liquid electrolyte in conventional lithium-ion batteries with thin-film solid-state lithium-ion conductors is a promising approach for increasing energy density, lifetime, and safety. In particular, Li 7 La 3 Zr 2 O 12 is appealing due to its high lithium-ion conductivity and wide electrochemical stability window. Further insights into thin-film processing of this material are required for its successful integration into solid-state batteries. In this work, we investigate the phase evolution of Li 7-3 x Ga x La 3 Zr 2 O 12 in thin films with various amounts of Li and Ga for stabilizing the cubic phase. Through this work, we gain valuable insights into the crystallization processes unique to thin films and are able to form dense Li 7-3 x Ga x La 3 Zr 2 O 12 layers stabilized in the cubic phase with high in-plane lithium-ion conductivities of up to 1.6 × 10 -5 S cm -1 at 30 °C. We also note the formation of cubic Li 7 La 3 Zr 2 O 12 at the relatively low temperature of 500 °C.
Interactive mission planning for a Space Shuttle flight experiment - A case history
NASA Technical Reports Server (NTRS)
Harris, H. M.
1986-01-01
Scientific experiments which use the Space Shuttle as a platform require the development of new operations techniques for the command and control of the instrument. Principal among these is the ability to simulate the complex maneuvers of the orbiter's path realistically. Computer generated graphics provide a window into the actual and predicted performance of the instrument and allow sophisticated control of the instrument under varying conditions. In October of 1984 the Shuttle carried a synthetic aperture radar built by JPL for the purpose of recording images of the earth surface. The mission deviated from planned operation in almost every conceivable way and provided an exacting test bed for concepts of interactive mission planning.
[Development of Nanotechnology for X-Ray Astronomy Instrumentation
NASA Technical Reports Server (NTRS)
Schattenburg, Mark L.
2004-01-01
This Research Grant provides support for development of nanotechnology for x-ray astronomy instrumentation. MIT has made significant progress in several development areas. In the last year we have made considerable progress in demonstrating the high-fidelity patterning and replication of x-ray reflection gratings. We developed a process for fabricating blazed gratings in silicon with extremely smooth and sharp sawtooth profiles, and developed a nanoimprint process for replication. We also developed sophisticated new fixturing for holding thin optics during metrology without causing distortion. We developed a new image processing algorithm for our Shack-Hartmann tool that uses Zernike polynomials. This has resulted in much more accurate and repeatable measurements on thin optics.
NASA Astrophysics Data System (ADS)
Moore, Christopher Samuel
2017-11-01
Advances in technology and instrumentation open new windows for observing astrophysical objects. The first half of my dissertation involves the development of atomic layer deposition (ALD) coatings to create high reflectivity UV mirrors for future satellite astronomical telescopes. Aluminum (Al) has intrinsic reflectance greater than 80% from 90 – 2,000 nm, but develops a native aluminum oxide (Al2O3) layer upon exposure to air that readily absorbs light below 250 nm. Thus, Al based UV mirrors must be protected by a transmissive overcoat. Traditionally, metal-fluoride overcoats such as MgF2 and LiF are used to mitigate oxidation but with caveats. We utilize a new metal fluoride (AlF3) to protect Al mirrors deposited by ALD. ALD allows for precise thickness control, conformal and near stoichiometric thin films. We prove that depositing ultra-thin ( 3 nm) ALD ALF3 to protect Al mirrors after removing the native oxide layer via atomic layer etching (ALE) enhances the reflectance near 90 nm from 5% to 30%.X-ray detector technology with high readout rates are necessary for the relatively bright Sun, particularly during large flares. The hot plasma in the solar corona generates X-rays, which yield information on the physical conditions of the plasma. The second half of my dissertation includes detector testing, characterization and solar science with the Miniature X-ray Solar Spectrometer (MinXSS) CubeSats. The MinXSS CubeSats employ Silicon Drift Diode (SDD) detectors called X123, which generate full sun spectrally resolved ( 0.15 FWHM at 5.9 keV) measurements of the sparsely measured, 0.5 – 12 keV range. The absolute radiometric calibration of the MinXSS instrument suite was performed at the National Institute for Standards and Technology (NIST) Synchrotron Ultraviolet Radiation Facility (SURF) and spectral resolution determined from radioactive sources. I used MinXSS along with data from the Geostationary Operational Environmental Satellites (GOES), Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI), Hinode X-ray Telescope (XRT), Hinode Extreme Ultraviolet Imaging Spectrometer (EIS) and Solar Dynamics Observatory (SDO) Atmospheric Imaging Assembly (AIA) to study the solar corona. This resulted in new insights on the coronal temperature distribution and elemental abundance variations for quiescence, active regions and during solar flares.
McStas 1.7 - a new version of the flexible Monte Carlo neutron scattering package
NASA Astrophysics Data System (ADS)
Willendrup, Peter; Farhi, Emmanuel; Lefmann, Kim
2004-07-01
Current neutron instrumentation is both complex and expensive, and accurate simulation has become essential both for building new instruments and for using them effectively. The McStas neutron ray-trace simulation package is a versatile tool for producing such simulations, developed in collaboration between Risø and ILL. The new version (1.7) has many improvements, among these added support for the popular Microsoft Windows platform. This presentation will demonstrate a selection of the new features through a simulation of the ILL IN6 beamline.
Absorption coefficients of solid NH3 from 50 to 7000 per cm
NASA Technical Reports Server (NTRS)
Sill, G.; Fink, U.; Ferraro, J. R.
1980-01-01
Thin-film spectra of solid NH3 at a resolution of 1 per cm were used to determine its absorption coefficient over the range 50-7000 per cm. The thin films were formed inside a liquid N2 cooled dewar using a variety of substrates and dewar windows. The spectra were recorded with two Fourier spectrometers, one covering the range from 1 to 4 microns and the other from 2.6 to 200 microns. The thickness of the films was measured with a laser interference technique. The absorption coefficients were determined by application of Lambert's law and by a fitting procedure to the observed spectra using thin-film theory. Good agreement was found with the absorption coefficients recently determined by other investigators over a more restricted wavelength range. A metastable phase was observed near a temperature of 90 K and its absorption coefficient is reported. No other major spectral changes with temperature were noted for the range 88-120 K.
Chemically Deposited Thin-Film Solar Cell Materials
NASA Technical Reports Server (NTRS)
Raffaelle, R.; Junek, W.; Gorse, J.; Thompson, T.; Harris, J.; Hehemann, D.; Hepp, A.; Rybicki, G.
2005-01-01
We have been working on the development of thin film photovoltaic solar cell materials that can be produced entirely by wet chemical methods on low-cost flexible substrates. P-type copper indium diselenide (CIS) absorber layers have been deposited via electrochemical deposition. Similar techniques have also allowed us to incorporate both Ga and S into the CIS structure, in order to increase its optical bandgap. The ability to deposit similar absorber layers with a variety of bandgaps is essential to our efforts to develop a multi-junction thin-film solar cell. Chemical bath deposition methods were used to deposit a cadmium sulfide (CdS) buffer layers on our CIS-based absorber layers. Window contacts were made to these CdS/CIS junctions by the electrodeposition of zinc oxide (ZnO). Structural and elemental determinations of the individual ZnO, CdS and CIS-based films via transmission spectroscopy, x-ray diffraction, x-ray photoelectron spectroscopy and energy dispersive spectroscopy will be presented. The electrical characterization of the resulting devices will be discussed.
NASA Astrophysics Data System (ADS)
Eichenlaub, Jesse B.
1998-04-01
At the 1997 conference DTI first reported on a low cost, thin, lightweight backlight for LCDs that generates a special illumination pattern to create autostereoscopic 3D images and can switch to conventional diffuse illumination for 2D images. The backlight is thin and efficient enough for use in portable computer and hand held games, as well as thin desktop displays. The system has been embodied in 5' (13 cm) diagonal backlights for gambling machines, and in the 12.1' (31 cm) diagonal DTI Virtual Window(TM) desktop product. During the past year, DTI has improved the technology considerably, reducing crosstalk, increasing efficiency, improving components for mass production, and developing prototypes that move the 3D viewing zones in response to the observer's head position. The paper will describe the 2D/3D backlights, improvements that have been made to their function, and their embodiments within the latest display products and prototypes.
Peel-and-Stick: Fabricating Thin Film Solar Cell on Universal Substrates
Lee, Chi Hwan; Kim, Dong Rip; Cho, In Sun; William, Nemeth; Wang, Qi; Zheng, Xiaolin
2012-01-01
Fabrication of thin-film solar cells (TFSCs) on substrates other than Si and glass has been challenging because these nonconventional substrates are not suitable for the current TFSC fabrication processes due to poor surface flatness and low tolerance to high temperature and chemical processing. Here, we report a new peel-and-stick process that circumvents these fabrication challenges by peeling off the fully fabricated TFSCs from the original Si wafer and attaching TFSCs to virtually any substrates regardless of materials, flatness and rigidness. With the peel-and-stick process, we integrated hydrogenated amorphous silicon (a-Si:H) TFSCs on paper, plastics, cell phone and building windows while maintaining the original 7.5% efficiency. The new peel-and-stick process enables further reduction of the cost and weight for TFSCs and endows TFSCs with flexibility and attachability for broader application areas. We believe that the peel-and-stick process can be applied to thin film electronics as well. PMID:23277871
Thin cirrus clouds - Seasonal distribution over oceans deduced from Nimbus-4 IRIS
NASA Technical Reports Server (NTRS)
Prabhakara, C.; Fraser, R. S.; Dalu, G.; Wu, Man-Li C.; Curran, R. J.
1988-01-01
Spectral differences in the extinction of the 10.8- and 12.6-micron bands of the IR window region, due to optically thin clouds, were found in the measurements made by both an airborne broadband IR radiometer and the IR interferometer spectrometer (IRIS) aboard the Nimbus-4 satellite; the extinction at 12.6 microns was significantly larger than that at 10.8 microns; both water and ice particles in the clouds can account for such spectral difference in extinction. Multiple scattering radiative transfer calculations of IRIS data revealed this spectral feature about 100 to 20 km away from the high-altitude cold clouds; it is assumed that this feature is related to the spreading of cirrus clouds. Based on this assumption, mean seasonal maps of the distribution of thin cirrus clouds over the oceans were deduced from the IRIS data. The maps show that such clouds are often present over the convectively active areas, such as ITCZ, SPCZ, and the Bay of Bengal during the summer monsoon.
All-back-Schottky-contact thin-film photovoltaics
NASA Astrophysics Data System (ADS)
Nardone, Marco
2016-02-01
The concept of All-Back-Schottky-Contact (ABSC) thin-film photovoltaic (TFPV) devices is introduced and evaluated using 2D numerical simulation. Reach-through Schottky junctions due to two metals of different work functions in an alternating, side-by-side pattern along the non-illuminated side generate the requisite built-in field. It is shown that our simulation method quantitatively describes existing data for a recently demonstrated heterojunction thin-film cell with interdigitated back contacts (IBCs) of one metal type. That model is extended to investigate the performance of ABSC devices with bimetallic IBCs within a pertinent parameter space. Our calculations indicate that 20% efficiency is achievable with micron-scale features and sufficient surface passivation. Bimetallic, micron-scale IBCs are readily fabricated using photo-lithographic techniques and the ABSC design allows for optically transparent surface passivation layers that need not be electrically conductive. The key advantages of the ABSC-TFPV architecture are that window layers, buffer layers, heterojunctions, and module scribing are not required because both contacts are located on the back of the device.
Peel-and-Stick: Fabricating Thin Film Solar Cell on Universal Substrates
NASA Astrophysics Data System (ADS)
Lee, Chi Hwan; Kim, Dong Rip; Cho, In Sun; William, Nemeth; Wang, Qi; Zheng, Xiaolin
2012-12-01
Fabrication of thin-film solar cells (TFSCs) on substrates other than Si and glass has been challenging because these nonconventional substrates are not suitable for the current TFSC fabrication processes due to poor surface flatness and low tolerance to high temperature and chemical processing. Here, we report a new peel-and-stick process that circumvents these fabrication challenges by peeling off the fully fabricated TFSCs from the original Si wafer and attaching TFSCs to virtually any substrates regardless of materials, flatness and rigidness. With the peel-and-stick process, we integrated hydrogenated amorphous silicon (a-Si:H) TFSCs on paper, plastics, cell phone and building windows while maintaining the original 7.5% efficiency. The new peel-and-stick process enables further reduction of the cost and weight for TFSCs and endows TFSCs with flexibility and attachability for broader application areas. We believe that the peel-and-stick process can be applied to thin film electronics as well.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Yubo; Zhang, Wenqing, E-mail: wqzhang@mail.sic.ac.cn, E-mail: pzhang3@buffalo.edu; State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050
2016-05-21
Photovoltaic performances of Cu-chalcogenides solar cells are strongly correlated with the absorber fundamental properties such as optimal bandgap, desired band alignment with window material, and high photon absorption ability. According to these criteria, we carry out a successive screening for 90 Cu-chalcogenides using efficient theoretical approaches. Besides the well-recognized CuInSe{sub 2} and Cu{sub 2}ZnSnSe{sub 4} materials, several novel candidates are identified to have optimal bandgaps of around 1.0–1.5 eV, spike-like band alignments with CdS window layer, sharp photon absorption edges, and high absorption coefficients. These new systems have great potential to be superior absorbers for photovolatic applications if their carrriermore » transport and defect properties are properly optimized.« less
El-Deftar, Moteaa M; Speers, Naomi; Eggins, Stephen; Foster, Simon; Robertson, James; Lennard, Chris
2014-08-01
A commercially available laser-induced breakdown spectroscopy (LIBS) instrument was evaluated for the determination of elemental composition of twenty Australian window glass samples, consisting of 14 laminated samples and 6 non-laminated samples (or not otherwise specified) collected from broken windows at crime scenes. In this study, the LIBS figures of merit were assessed in terms of accuracy, limits of detection and precision using three standard reference materials (NIST 610, 612, and 1831). The discrimination potential of LIBS was compared to that obtained using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), X-ray microfluorescence spectroscopy (μXRF) and scanning electron microscopy energy dispersive X-ray spectrometry (SEM-EDX) for the analysis of architectural window glass samples collected from crime scenes in the Canberra region, Australia. Pairwise comparisons were performed using a three-sigma rule, two-way ANOVA and Tukey's HSD test at 95% confidence limit in order to investigate the discrimination power for window glass analysis. The results show that the elemental analysis of glass by LIBS provides a discrimination power greater than 97% (>98% when combined with refractive index data), which was comparable to the discrimination powers obtained by LA-ICP-MS and μXRF. These results indicate that LIBS is a feasible alternative to the more expensive LA-ICP-MS and μXRF options for the routine forensic analysis of window glass samples. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Software structure for Vega/Chara instrument
NASA Astrophysics Data System (ADS)
Clausse, J.-M.
2008-07-01
VEGA (Visible spEctroGraph and polArimeter) is one of the focal instruments of the CHARA array at Mount Wilson near Los Angeles. Its control system is based on techniques developed on the GI2T interferometer (Grand Interferometre a 2 Telescopes) and on the SIRIUS fibered hyper telescope testbed at OCA (Observatoire de la Cote d'Azur). This article describes the software and electronics architecture of the instrument. It is based on local network architecture and uses also Virtual Private Network connections. The server part is based on Windows XP (VC++). The control software is on Linux (C, GTK). For the control of the science detector and the fringe tracking systems, distributed API use real-time techniques. The control software gathers all the necessary informations of the instrument. It allows an automatic management of the instrument by using an original task scheduler. This architecture intends to drive the instrument from remote sites, such as our institute in South of France.
Design and fabrication of self-assembled thin films
NASA Astrophysics Data System (ADS)
Topasna, Daniela M.; Topasna, Gregory A.
2015-10-01
Students experience the entire process of designing, fabricating and testing thin films during their capstone course. The films are fabricated by the ionic-self assembled monolayer (ISAM) technique, which is suited to a short class and is relatively rapid, inexpensive and environmentally friendly. The materials used are polymers, nanoparticles, and small organic molecules that, in various combinations, can create films with nanometer thickness and with specific properties. These films have various potential applications such as pH optical sensors or antibacterial coatings. This type of project offers students an opportunity to go beyond the standard lecture and labs and to experience firsthand the design and fabrication processes. They learn new techniques and procedures, as well as familiarize themselves with new instruments and optical equipment. For example, students learn how to characterize the films by using UV-Vis-NIR spectrophotometry and in the process learn how the instruments operate. This work compliments a previous exercise that we introduced where students use MATHCAD to numerically model the transmission and reflection of light from thin films.
Portable and programmable clinical EOG diagnostic system.
Chen, S C; Tsai, T T; Luo, C H
2000-01-01
Monitoring eye movements is clinically important in diagnosis of diseases of the central nervous system. Electrooculography (EOG) is one method of obtaining such records which uses skin electrodes, and utilizes the anterior posterior polarization of the eye. A new EOG diagnostic system has been developed that utilizes two off-the-shelf portable notebook computers, one projector and simple electronic hardware. It can be operated under Windows 95, 98, NT, and has significant advantages over any other similar equipment, including programmability, portability, improved safety and low cost. Especially, portability of the instrument is extremely important for acutely ill or handicapped patients. The purpose of this paper is to introduce the techniques of computer animation, data acquisition, real time analysis of measured data, and database management to implement a portable, programmable and inexpensive contacting EOG instrument. It is very convenient to replace the present expensive, inflexible and large-sized commercially available EOG instruments. A lot of interesting stimulation patterns for clinical application can be created easily in different shape, time sequence, and colour by programming in Delphi language. With the help of Winstar (a software package that is used to control I/O and interrupt functions of the computer under Windows 95, 98, NT), the I/O communication between two notebook computers and A/D interface module can be effectively programmed. In addition, the new EOG diagnostic system is battery operated and it has the advantages of low noise as well as isolation from electricity. Two kinds of EOG tests, pursuit and saccade, were performed on 20 normal subjects with this new portable and programmable instrument. Based on the test result, the performance of the new instrument is superior to the other commercially available instruments. In conclusion, we hope that it will be more convenient for doctors and researchers to do the clinical EOG diagnosis and basic medical science research by using this new creation.
Yu, Jung-Hoon; Nam, Sang-Hun; Lee, Ji Won; Boo, Jin-Hyo
2016-01-01
This paper presents the preparation of high-quality vanadium dioxide (VO2) thermochromic thin films with enhanced visible transmittance (Tvis) via radio frequency (RF) sputtering and plasma enhanced chemical vapor deposition (PECVD). VO2 thin films with high Tvis and excellent optical switching efficiency (Eos) were successfully prepared by employing SiO2 as a passivation layer. After SiO2 deposition, the roughness of the films was decreased 2-fold and a denser structure was formed. These morphological changes corresponded to the results of optical characterization including the haze, reflectance and absorption spectra. In spite of SiO2 coating, the phase transition temperature (Tc) of the prepared films was not affected. Compared with pristine VO2, the total layer thickness after SiO2 coating was 160 nm, which is an increase of 80 nm. Despite the thickness change, the VO2 thin films showed a higher Tvis value (λ 650 nm, 58%) compared with the pristine samples (λ 650 nm, 43%). This enhancement of Tvis while maintaining high Eos is meaningful for VO2-based smart window applications. PMID:28773679
Effects of different wetting layers on the growth of smooth ultra-thin silver thin films
NASA Astrophysics Data System (ADS)
Ni, Chuan; Shah, Piyush; Sarangan, Andrew M.
2014-09-01
Ultrathin silver films (thickness below 10 nm) are of great interest as optical coatings on windows and plasmonic devices. However, producing these films has been a continuing challenge because of their tendency to form clusters or islands rather than smooth contiguous thin films. In this work we have studied the effect of Cu, Ge and ZnS as wetting layers (1.0 nm) to achieve ultrasmooth thin silver films. The silver films (5 nm) were grown by RF sputter deposition on silicon and glass substrates using a few monolayers of the different wetting materials. SEM imaging was used to characterize the surface properties such as island formation and roughness. Also the optical properties were measured to identify the optical impact of the different wetting layers. Finally, a multi-layer silver based structure is designed and fabricated, and its performance is evaluated. The comparison between the samples with different wetting layers show that the designs with wetting layers which have similar optical properties to silver produce the best overall performance. In the absence of a wetting layer, the measured optical spectra show a significant departure from the model predictions, which we attribute primarily to the formation of clusters.
Low polarity water, a novel transition species at the polyethylene-water interface.
Kosower, Edward M; Borz, Galina
2015-10-14
The bridge between water repelling and water-attracting regions is recognized here as low polarity water, a novel "neutral" form of water; its identity as a dipole-dipole water dimer is supported by spectroscopic evidence of its presence in thin films of water on a polyethylene surface. High resolution (0.5 cm(-1)), low signal energies (Sg 100) and short scans (0.1 s) are used to ensure that all peaks are detected. Thin films may be trapped between two polyethylene windows, affirming the low polarity of such water; the spectra of the trapped films ("sandwich") are similar to those from a subtraction procedure. Use of the "sandwich" is a new and useful technique in surface studies. In general, intermediate forms might bridge incompatibility between different regimes, from sets of molecules (chemistry and physics) to sets of organisms (biology and sociology). Thin films of water on polyethylene also display strong and transient peaks of water oligomers, cyclic pentamers and cyclic hexamers (chair and boat), bicyclic hexamers (books 1 and 2) and tricyclic hexamers (prism) that have been previously identified in thin films of water on a silver halide surface.
Dr. John Mather and the James Webb Space Telescope
2017-12-08
Nobel Laureate and James Webb Space Telescope project scientist Dr. John Mather takes a selfie with the telescope. May 4, 2016 was a rare day for JWST, as it briefly faced the cleanroom observation window. The telescope was eventually rotated face-down in prep for the installation of the flight instruments. Credit: Meredith Gibb
Spectral definition of the ArTeMiS instrument
NASA Astrophysics Data System (ADS)
Haynes, Vic; Maffei, Bruno; Pisano, Giampaolo; Dubreuil, Didier; Delisle, Cyrille; Le Pennec, Jean; Hurtado, Norma
2014-07-01
ArTeMiS is a sub-millimetre camera to be operated, on the Atacama Pathfinder Experiment Telescope (APEX). The ultimate goal is to observe simultaneously in three atmospheric spectral windows in the region of 200, 350 and 450 microns. We present the filtering scheme, which includes the cryostat window, thermal rejection elements, band separation and spectral isolation, which has been adopted for this instrument. This was achieved using a combination of scattering, Yoshinaga filters, organic dyes and Ulrich type embedded metallic mesh devices. Design of the quasi-optical mesh components has been developed by modelling with an in-house developed code. For the band separating dichroics, which are used with an incidence angle of 35 deg, further modelling has been performed with HFSS (Ansoft). Spectral characterization of the components for the 350 and 450 bands have been performed with a Martin-Puplett Polarizing Fourier Transform Spectrometer. While for the first commissioning and observation campaign, one spectral band only was operational (350 microns), we report on the design of the 200, 350 and 450 micron bands.
Morphological Feature Extraction for Automatic Registration of Multispectral Images
NASA Technical Reports Server (NTRS)
Plaza, Antonio; LeMoigne, Jacqueline; Netanyahu, Nathan S.
2007-01-01
The task of image registration can be divided into two major components, i.e., the extraction of control points or features from images, and the search among the extracted features for the matching pairs that represent the same feature in the images to be matched. Manual extraction of control features can be subjective and extremely time consuming, and often results in few usable points. On the other hand, automated feature extraction allows using invariant target features such as edges, corners, and line intersections as relevant landmarks for registration purposes. In this paper, we present an extension of a recently developed morphological approach for automatic extraction of landmark chips and corresponding windows in a fully unsupervised manner for the registration of multispectral images. Once a set of chip-window pairs is obtained, a (hierarchical) robust feature matching procedure, based on a multiresolution overcomplete wavelet decomposition scheme, is used for registration purposes. The proposed method is validated on a pair of remotely sensed scenes acquired by the Advanced Land Imager (ALI) multispectral instrument and the Hyperion hyperspectral instrument aboard NASA's Earth Observing-1 satellite.
Calibration Tunnel for High Speed
NASA Technical Reports Server (NTRS)
Pretsch, J.
1946-01-01
For the nvestigation of measuring instruments at higher speeds up to a Mach number 0.7 a tunnel with closed test section was built in 1942 which was as simple and cheap as possble. The blower was a radial blower with straight sheet vanes of 800-millimeter diameter the tips of which were bent backward a little. The blower sucks the air through a honeycomb of diameter 1.2 neter with wide meshes. The air is then accelerated in a short cone with smooth transition to the test section. The cylindrical test section of 200-milimeter diameter has two windows (which are displaced 180 deg from each other. The instruments may be introduced and observed through and observed through these windows. . The cross section is then enlarged by a straight diffuser 3.5 meters long and reaches the ninefold cross section. The air flows back into the room through a disk diffuser of 2-meter diameter. The maximum speed in the jet is 250 m/s for a drive power of 35 kT., if there are no installations in the jet. The velocity is determined by pressure holed along the test section.
Biaxial deformation behaviour of poly-ether-ether-ketone
NASA Astrophysics Data System (ADS)
Turner, Josh; Menary, Gary; Martin, Peter
2018-05-01
The biaxial tensile properties of thin poly-ether-ether-ketone (PEEK) films are presented. Investigation into the biaxial mechanical behaviour of PEEK films will provide a preliminary insight into the anticipated stress/strain response, and potential suitability, to the possible fabrication of thin walled parts through stretch blow moulding and thermoforming processes - with the multi-axial state of strain imposed onto the heated thermoplastic sheet representative of the expected strain history experienced during these material forming processes. Following identification of the prospective forming temperature window, the biaxial mechanical behaviour of the material is characterized under differing modes of deformation, at a nominal strain rate of 1 s-1. The temperature dependence is outlined within - with an appreciable increase in flow behaviour correlated with specimen temperature exceeding its glass transition temperature (Tg).
Xu, Man; Wachters, Arthur J H; van Deelen, Joop; Mourad, Maurice C D; Buskens, Pascal J P
2014-03-10
We present a systematic study of the effect of variation of the zinc oxide (ZnO) and copper indium gallium (di)selenide (CIGS) layer thickness on the absorption characteristics of CIGS solar cells using a simulation program based on finite element method (FEM). We show that the absorption in the CIGS layer does not decrease monotonically with its layer thickness due to interference effects. Ergo, high precision is required in the CIGS production process, especially when using ultra-thin absorber layers, to accurately realize the required thickness of the ZnO, cadmium sulfide (CdS) and CIGS layer. We show that patterning the ZnO window layer can strongly suppress these interference effects allowing a higher tolerance in the production process.
Fan, Ching-Lin; Lin, Wei-Chun; Chang, Hsiang-Sheng; Lin, Yu-Zuo; Huang, Bohr-Ran
2016-01-13
In this paper, the top-contact (TC) pentacene-based organic thin-film transistor (OTFT) with a tetrafluorotetracyanoquinodimethane (F₄TCNQ)-doped pentacene interlayer between the source/drain electrodes and the pentacene channel layer were fabricated using the co-evaporation method. Compared with a pentacene-based OTFT without an interlayer, OTFTs with an F₄TCNQ:pentacene ratio of 1:1 showed considerably improved electrical characteristics. In addition, the dependence of the OTFT performance on the thickness of the F₄TCNQ-doped pentacene interlayer is weaker than that on a Teflon interlayer. Therefore, a molecular doping-type F₄TCNQ-doped pentacene interlayer is a suitable carrier injection layer that can improve the TC-OTFT performance and facilitate obtaining a stable process window.
Structure and enhanced thermochromic performance of low-temperature fabricated VO 2/V 2O 3 thin film
Sun, Guangyao; Cao, Xun; Gao, Xiang; ...
2016-10-06
For VO 2-based smart window manufacture, it is a long-standing demand for high-quality thin films deposited at low temperature. In this paper, the thermochromic films of VO 2 were deposited by a magnetron sputtering method at a fairly low temperature of 250 °C without subsequent annealing by embedding a V 2O 3 interlayer. V 2O 3 acts as a seed layer to lower the depositing temperature and buffer layer to epitaxial grow VO 2 film. The VO 2/V 2O 3 films display high solar modulating ability and narrow hysteresis loop. Finally, our data can serve as a promising point formore » industrial production with high degree of crystallinity at a low temperature.« less
AN INSTRUMENT TO MEASURE THE ELECTRICAL CONDUCTIVITY OF ARC PLASMA JETS
The instrument was calibrated by moving aluminum or graphite rods through the transducer. By using thin-wall, stainless steel tubing, the influence ... function for the transducer was also obtained. Tests were run on two different arc plasma jet facilities. Values of s, u ranged from 0.02 to 9 megamhos per second. (Author)
ERIC Educational Resources Information Center
Torres y Torres, Janelle L.; Hiley, Shauna L.; Lorimor, Steven P.; Rhoad, Jonathan S.; Caldwell, Benjamin D.; Zweerink, Gerald L.; Ducey, Michael
2015-01-01
The Characterization and Analysis of a Product (CAP) project is used to introduce first-semester general chemistry students to chemical instrumentation through the analysis of caffeine-containing beverage products. Some examples of these products have included coffee, tea, and energy drinks. Students perform at least three instrumental experiments…
POLOCAM: a millimeter wavelength cryogenic polarimeter prototype for MUSIC-POL
NASA Astrophysics Data System (ADS)
Laurent, Glenn T.; Vaillancourt, John E.; Savini, Giorgio; Ade, Peter A. R.; Beland, Stephane; Glenn, Jason; Hollister, Matthew I.; Maloney, Philip R.; Sayers, Jack
2012-09-01
As a proof-of-concept, we have constructed and tested a cryogenic polarimeter in the laboratory as a prototype for the MUSIC instrument (Multiwavelength Sub/millimeter Kinetic Inductance Camera). The POLOCAM instrument consists of a rotating cryogenic polarization modulator (sapphire half-waveplate) and polarization analyzer (lithographed copper polarizers deposited on a thin film) placed into the optical path at the Lyot stop (4K cold pupil stop) in a cryogenic dewar. We present an overview of the project, design and performance results of the POLOCAM instrument (including polarization efficiencies and instrumental polarization), as well as future application to the MUSIC-POL instrument.
1994-04-25
103070൚I1, Wohinuoan. oc 20603. 1. AGENCY USE ONLY ILaevo NW) j2. REPORT DATE 3. REPORT TYPE AND DATES COVERED I April 25, 1994 4. TITLE AND SUBTITLE 5...effectively use the radiation of the Na pinch to fully ionize this window and thereby reduce its absorption. One of the most attractive methods to...vacancies is explored. The use of thin multiple layers is a potentially promising method of obtaining information about ionization and (possibly) also
Geminiani, Alessandro; Papadimitriou, Dimitrios E V; Ercoli, Carlo
2011-11-01
Several techniques have been proposed to manage patients with insufficient bone height for implant placement in the posterior maxilla. The lateral approach to sinus elevation is a successful procedure, with percentages of success close to 100%. Unfortunately, a frequent complication encountered during sinus elevation procedure is perforation of the Schneiderian membrane. In this clinical report, the authors present the application of a diamond coated sonic tip and an air-driven sonic instrument, commonly used in prosthodontics for the preparation of the lateral window osteotomy during sinus augmentation procedures. Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.
2003-03-20
KENNEDY SPACE CENTER, Fla. - With cables released, this Mars Exploration Rover sits on the floor of the Payload Hazardous Servicing Facility. Processing of the rovers, cruise stage, lander and heat shield elements is ongoing. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-03-20
KENNEDY SPACE CENTER, Fla. - With cables released, this Mars Exploration Rover (MER) sits on the floor of the Payload Hazardous Servicing Facility. Processing of the rovers, cruise stage, lander and heat shield elements is ongoing. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-03-20
KENNEDY SPACE CENTER, Fla. - A worker in the Payload Hazardous Servicing Facility makes adjustments on one of the Mars Exploration Rovers (MER). Processing of the rovers, cruise stage, lander and heat shield elements is ongoing. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-03-28
KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, workers adjust the position of the Mars Exploration Rover-2 (MER-2) on the base petal of its lander assembly. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover, a window opening June 25.
2003-03-21
KENNEDY SPACE CENTER, Fla. - In the Payload Hazardous Servicing Facility, the Mars Exploration Rover-2 (MER-2) has rotated. Atop the rover can be seen the cameras, mounted on a Pancam Mast Assembly (PMA). Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-03-21
KENNEDY SPACE CENTER, Fla. - In the Payload Hazardous Servicing Facility, workers watch as the Mars Exploration Rover-2 (MER-2) rolls over ramps to test its mobility and maneuverability. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-03-21
KENNEDY SPACE CENTER, Fla. - In the Payload Hazardous Servicing Facility, workers watch as the Mars Exploration Rover-2 (MER-2) rolls over ramps to test its mobility and maneuverability. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-03-21
KENNEDY SPACE CENTER, Fla. - In the Payload Hazardous Servicing Facility, workers watch as the Mars Exploration Rover-2 (MER-2) rolls over ramps to test its mobility and maneuverability. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25.
2003-03-28
KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, workers move the Mars Exploration Rover-2 (MER-2) into position over the base petal of its lander assembly. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover, a window opening June 25.
2003-03-28
KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, workers lower the Mars Exploration Rover-2 (MER-2) onto the base petal of its lander assembly. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover, a window opening June 25.
2003-03-20
KENNEDY SPACE CENTER, Fla. - Workers in the Payload Hazardous Servicing Facility look over one of the Mars Exploration Rovers (MER). Processing of the rovers, cruise stage, lander and heat shield elements is ongoing. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-03-20
KENNEDY SPACE CENTER, FLA. - One of the Mars Exploration Rovers (MER) sits on a stand in the Payload Hazardous Servicing Facility. Processing of the rovers, cruise stage, lander and heat shield elements is ongoing. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-03-28
KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, workers prepare the base petal of a lander assembly to receive the Mars Exploration Rover-2 (MER-2). Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover, a window opening June 25.
2003-02-04
KENNEDY SPACE CENTER, FLA. - Shown are the Lander pedals for MER-1. These pedals fold up covering the Rover, which will be attached to the base pedal (not shown--empty spot in the center.) Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
2003-01-28
KENNEDY SPACE CENTER, FLA. - After being cleaned up, the Mars Exploration Rover -2 is ready to be moved to a workstand in the Payload Hazardous Servicing Facility. Set to launch in 2003, the Mars Exploration Rover Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, 2003, and the second rover a window opening June 25, 2003.
2003-03-28
KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, workers move the Mars Exploration Rover-2 (MER-2) towards the base petal of its lander assembly. Set to launch in Spring 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day over various terrain. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover, a window opening June 25.
2003-01-31
KENNEDY SPACE CENTER, FLA. - Suspended by an overhead crane in the Payload Hazardous Servicing Facility, the Mars Exploration Rover (MER) aeroshell is guided by workers as it moves to a rotation stand. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards (100 meters) each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
NASA Astrophysics Data System (ADS)
Varela Rodriguez, F.
2011-12-01
The control system of each of the four major Experiments at the CERN Large Hadron Collider (LHC) is distributed over up to 160 computers running either Linux or Microsoft Windows. A quick response to abnormal situations of the computer infrastructure is crucial to maximize the physics usage. For this reason, a tool was developed to supervise, identify errors and troubleshoot such a large system. Although the monitoring of the performance of the Linux computers and their processes was available since the first versions of the tool, it is only recently that the software package has been extended to provide similar functionality for the nodes running Microsoft Windows as this platform is the most commonly used in the LHC detector control systems. In this paper, the architecture and the functionality of the Windows Management Instrumentation (WMI) client developed to provide centralized monitoring of the nodes running different flavour of the Microsoft platform, as well as the interface to the SCADA software of the control systems are presented. The tool is currently being commissioned by the Experiments and it has already proven to be very efficient optimize the running systems and to detect misbehaving processes or nodes.
NASA Astrophysics Data System (ADS)
Korhonen, Rami K.; Saarakkala, Simo; Töyräs, Juha; Laasanen, Mikko S.; Kiviranta, Ilkka; Jurvelin, Jukka S.
2003-06-01
Softening of articular cartilage, mainly attributable to deterioration of superficial collagen network and depletion of proteoglycans, is a sign of incipient osteoarthrosis. Early diagnosis of osteoarthrosis is essential to prevent the further destruction of the tissue. During the past decade, a few arthroscopic instruments have been introduced for the measurement of cartilage stiffness; these can be used to provide a sensitive measure of cartilage status. Ease of use, accuracy and reproducibility of the measurements as well as a low risk of damaging cartilage are the main qualities needed in any clinically applicable instrument. In this study, we have modified a commercially available arthroscopic indentation instrument to better fulfil these requirements when measuring cartilage stiffness in joints with thin cartilage. Our novel configuration was validated by experimental testing as well as by finite element (FE) modelling. Experimental and numerical tests indicated that it would be better to use a smaller reference plate and a lower pressing force (3 N) than those used in the original instrument (7-10 N). The reproducibility (CV = 5.0%) of the in situ indentation measurements was improved over that of the original instrument (CV = 7.6%), and the effect of material thickness on the indentation response was smaller than that obtained with the original instrument. The novel configuration showed a significant linear correlation between the indenter force and the reference dynamic modulus of cartilage in unconfined compression, especially in soft tissue (r = 0.893, p < 0.001, n = 16). FE analyses with a transversely isotropic poroelastic model indicated that the instrument was suitable for detecting the degeneration of superficial cartilage. In summary, the instrument presented in this study allows easy and reproducible measurement of cartilage stiffness, also in thin cartilage, and therefore represents a technical improvement for the early diagnosis of osteoarthrosis during arthroscopy.
The role of the space station in earth science research
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kaye, Jack A.
1999-01-22
The International Space Station (ISS) has the potential to be a valuable platform for earth science research. By virtue of its being in a mid-inclination orbit (51.5 deg.), ISS provides the opportunity for nadir viewing of nearly 3/4 of the Earth's surface, and allows viewing to high latitudes if limb-emission or occultation viewing techniques are used. ISS also provides the opportunity for viewing the Earth under a range of lighting conditions, unlike the polar sun-synchronous satellites that are used for many earth observing programs. The ISS is expected to have ample power and data handling capability to support Earth-viewing instruments,more » provide opportunities for external mounting and retrieval of instruments, and be in place for a sufficiently long period that long-term data records can be obtained. On the other hand, there are several questions related to contamination, orbital variations, pointing knowledge and stability, and viewing that are of concern in consideration of ISS for earth science applications. The existence of an optical quality window (the Window Observational Research Facility, or WORF), also provides the opportunity for Earth observations from inside the pressurized part of ISS. Current plans by NASA for earth science research from ISS are built around the Stratospheric Aerosol and Gas Experiment (SAGE III) instrument, planned for launch in 2002.« less
Deconvolution of Energy Spectra in the ATIC Experiment
NASA Technical Reports Server (NTRS)
Batkov, K. E.; Panov, A. D.; Adams, J. H.; Ahn, H. S.; Bashindzhagyan, G. L.; Chang, J.; Christl, M.; Fazley, A. R.; Ganel, O.; Gunasigha, R. M.;
2005-01-01
The Advanced Thin Ionization Calorimeter (ATIC) balloon-borne experiment is designed to perform cosmic- ray elemental spectra measurements from below 100 GeV up to tens TeV for nuclei from hydrogen to iron. The instrument is composed of a silicon matrix detector followed by a carbon target, interleaved with scintillator tracking layers, and a segmented BGO calorimeter composed of 320 individual crystals totalling 18 radiation lengths, used to determine the particle energy. The technique for deconvolution of the energy spectra measured in the thin calorimeter is based on detailed simulations of the response of the ATIC instrument to different cosmic ray nuclei over a wide energy range. The method of deconvolution is described and energy spectrum of carbon obtained by this technique is presented.
CARMENES. IV: instrument control software
NASA Astrophysics Data System (ADS)
Guàrdia, Josep; Colomé, Josep; Ribas, Ignasi; Hagen, Hans-Jürgen; Morales, Rafael; Abril, Miguel; Galadí-Enríquez, David; Seifert, Walter; Sánchez Carrasco, Miguel A.; Quirrenbach, Andreas; Amado, Pedro J.; Caballero, Jose A.; Mandel, Holger
2012-09-01
The overall purpose of the CARMENES instrument is to perform high-precision measurements of radial velocities of late-type stars with long-term stability. CARMENES will be installed in 2014 at the 3.5 m telescope in the German- Spanish Astronomical Center at Calar Alto observatory (CAHA, Spain) and will be equipped with two spectrographs in the near-infrared and visible windows. The technology involved in such instrument represents a challenge at all levels. The instrument coordination and management is handled by the Instrument Control System (ICS), which is responsible of carrying out the operations of the different subsystems and providing a tool to operate the instrument from low to high user interaction level. The main goal of the ICS and the CARMENES control layer architecture is to maximize the instrument efficiency by reducing time overheads and by operating it in an integrated manner. The ICS implements the CARMENES operational design. A description of the ICS architecture and the application programming interfaces for low- and high-level communication is given. Internet Communications Engine is the technology selected to implement most of the interface protocols.
[Cardiovascular circulation feedback control treatment instrument].
Ge, Yu-zhi; Zhu, Xing-huan; Sheng, Guo-tai; Cao, Ping-liang; Liu, Dong-sheng; Wu, Zhi-ting
2005-07-01
The cardiovascular circulation feedback control treatment instrument (CFCTI) is an automatic feedback control treatment system, which has the function of monitoring, alarming, trouble self-diagnosis and testing on the line in the closed loop. The instrument is designed based on the successful clinical experiences and the data are inputted into the computer in real-time through a pressure sensor and A/D card. User interface window is set up for the doctor's choosing different medicine. The orders are outputted to control the dose of medicine through the transfusion system. The response to medicine is updated continually. CFCTI can avoid the man-made errors and the long interval of sampling. Its reliability and accuracy in rescuing the critical patients are much higher than the traditional methods.
NASA Technical Reports Server (NTRS)
1990-01-01
Scientific Instruments, Inc. has now developed a second generation, commercially available instrument to detect flames in hazardous environments, typically refineries, chemical plants and offshore drilling platforms. The Model 74000 detector incorporates a sensing circuit that detects UV radiation in a 100 degree conical field of view extending as far as 250 feet from the instrument. It operates in a bandwidth that makes it virtually 'blind' to solar radiation while affording extremely high sensitivity to ultraviolet flame detection. A 'windowing' technique accurately discriminates between background UV radiation and ultraviolet emitted from an actual flame, hence the user is assured of no false alarms. Model 7410CP is a combination controller and annunciator panel designed to monitor and control as many as 24 flame detectors. *Model 74000 is no longer being manufactured.
Gamma-ray astronomy: From Fermi up to the HAWC high-energy {gamma}-ray observatory in Sierra Negra
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carraminana, Alberto; Collaboration: HAWC Collaboration
Gamma-rays represent the most energetic electromagnetic window for the study of the Universe. They are studied both from space at MeV and GeV energies, with instruments like the Fermi{gamma}-ray Space Telescope, and at TeV energies with ground based instruments profiting of particle cascades in the atmosphere and of the Cerenkov radiation of charged particles in the air or in water. The Milagro gamma-ray observatory represented the first instrument to successfully implement the water Cerenkov technique for {gamma}-ray astronomy, opening the ground for the more sensitive HAWC {gamma}-ray observatory, currently under development in the Sierra Negra site and already providing earlymore » science results.« less
Future science issues for Galactic very-high-energy gamma-ray astronomy
NASA Astrophysics Data System (ADS)
Torres, Diego F.
2008-12-01
This work intends to provide a brief summary of some of the Galactic science issues for the next generation of very high energy (VHE) instruments. The latter is here generically understood, as an instrument or set of instruments providing about one order of magnitude more sensitivity at its central energy (at about 1 TeV), but extending the observational window to have a real broadband capability (from a few tens of GeV up to tens of TeV) exceeding at low energies the current VHE threshold for observations set by MAGIC as well as the few-tens-of-GeV sensitivity set by Fermi. Science topics regarding populations of emitters, pulsars and their nebula, binaries, supernova remnants, stars, and their associations, are discussed.
NASA Astrophysics Data System (ADS)
Carlson, Scott M.
1993-06-01
The design of a high resolution plane grating all-reflection Michelson interferometer for ionospheric spectroscopy was analyzed using ray tracing techniques. This interferometer produces an interference pattern whose spatial frequency is wavelength dependent. The instrument is intended for remote observations of the atomic oxygen triplet emission line profile at 1304 A in the thermosphere from sounding rocket or satellite platforms. The device was modeled using the PC-based ray tracing application, DART, and results analyzed through fourier techniques using the PC with Windows version of the Interactive Data Language (IDL). Through these methods, instrument resolution, resolving power, and bandpass were determined. An analysis of the effects of aperture size and shape on instrument performance was also conducted.
Some strategies for quantitative scanning Auger electron microscopy
NASA Technical Reports Server (NTRS)
Browning, R.; Peacock, D. C.; Prutton, M.
1985-01-01
The general applicability of power law forms of the background in electron spectra is pointed out and exploited for background removal from under Auger peaks. This form of B(E) is found to be extremely sensitive to instrumental alignment and to fault-free construction - an observation which can be used to set up analyser configurations in an accurate way. Also, differences between N(E) and B(E) can be used to derive a spectrometer transmission function T(E). The questions of information density in an energy-analysing spatially-resolving instrument are addressed after reliable instrumental characterization has been established. Strategies involving ratio histograms, showing the population distribution of the ratio of a pair of Auger peak heights, composition scatter diagrams and windowed imaging are discussed and illustrated.
Hossain, Md Anower; Wang, Mingqing; Choy, Kwang-Leong
2015-10-14
Chalcopyrite Cu(In,Ga)(S,Se)2 (CIGSSe) thin films have been deposited by a novel, nonvacuum, and cost-effective electrostatic spray-assisted vapor deposition (ESAVD) method. The generation of a fine aerosol of precursor solution, and their controlled deposition onto a molybdenum substrate, results in adherent, dense, and uniform Cu(In,Ga)S2 (CIGS) films. This is an essential tool to keep the interfacial area of thin film solar cells to a minimum value for efficient charge separation as it helps to achieve the desired surface smoothness uniformity for subsequent cadmium sulfide and window layer deposition. This nonvacuum aerosol based approach for making the CIGSSe film uses environmentally benign precursor solution, and it is cheaper for producing solar cells than that of the vacuum-based thin film solar technology. An optimized CIGSSe thin film solar cell with a device configuration of molybdenum-coated soda-lime glass substrate/CIGSSe/CdS/i-ZnO/AZO shows the photovoltaic (j-V) characteristics of Voc=0.518 V, jsc=28.79 mA cm(-2), fill factor=64.02%, and a promising power conversion efficiency of η=9.55% under simulated AM 1.5 100 mW cm(-2) illuminations, without the use of an antireflection layer. This demonstrates the potential of ESAVD deposition as a promising alternative approach for making thin film CIGSSe solar cells at a lower cost.
Electromagnetic Field Penetration Studies
NASA Technical Reports Server (NTRS)
Deshpande, M.D.
2000-01-01
A numerical method is presented to determine electromagnetic shielding effectiveness of rectangular enclosure with apertures on its wall used for input and output connections, control panels, visual-access windows, ventilation panels, etc. Expressing EM fields in terms of cavity Green's function inside the enclosure and the free space Green's function outside the enclosure, integral equations with aperture tangential electric fields as unknown variables are obtained by enforcing the continuity of tangential electric and magnetic fields across the apertures. Using the Method of Moments, the integral equations are solved for unknown aperture fields. From these aperture fields, the EM field inside a rectangular enclosure due to external electromagnetic sources are determined. Numerical results on electric field shielding of a rectangular cavity with a thin rectangular slot obtained using the present method are compared with the results obtained using simple transmission line technique for code validation. The present technique is applied to determine field penetration inside a Boeing-757 by approximating its passenger cabin as a rectangular cavity filled with a homogeneous medium and its passenger windows by rectangular apertures. Preliminary results for, two windows, one on each side of fuselage were considered. Numerical results for Boeing-757 at frequencies 26 MHz, 171-175 MHz, and 428-432 MHz are presented.
SuperADAM: Upgraded polarized neutron reflectometer at the Institut Laue-Langevin
DOE Office of Scientific and Technical Information (OSTI.GOV)
Devishvili, A.; Zhernenkov, K.; Institut Laue-Langevin, BP 156, 38042 Grenoble
2013-02-15
A new neutron reflectometer SuperADAM has recently been built and commissioned at the Institut Laue-Langevin, Grenoble, France. It replaces the previous neutron reflectometer ADAM. The new instrument uses a solid state polarizer/wavelength filter providing a highly polarized (up to 98.6%) monochromatic neutron flux of 8 Multiplication-Sign 10{sup 4} n cm{sup -2} s{sup -1} with monochromatization {Delta}{lambda}/{lambda}= 0.7% and angular divergence {Delta}{alpha}= 0.2 mrad. The instrument includes both single and position sensitive detectors. The position sensitive detector allows simultaneous measurement of specular reflection and off-specular scattering. Polarization analysis for both specular reflection and off-specular scattering is achieved using either mirror analyzersmore » or a {sup 3}He spin filter cell. High efficiency detectors, low background, and high flux provides a dynamic range of up to seven decades in reflectivity. Detailed specifications and the instrument capabilities are illustrated with examples of recently collected data in the fields of thin film magnetism and thin polymer films.« less
SuperADAM: Upgraded polarized neutron reflectometer at the Institut Laue-Langevin
NASA Astrophysics Data System (ADS)
Devishvili, A.; Zhernenkov, K.; Dennison, A. J. C.; Toperverg, B. P.; Wolff, M.; Hjörvarsson, B.; Zabel, H.
2013-02-01
A new neutron reflectometer SuperADAM has recently been built and commissioned at the Institut Laue-Langevin, Grenoble, France. It replaces the previous neutron reflectometer ADAM. The new instrument uses a solid state polarizer/wavelength filter providing a highly polarized (up to 98.6%) monochromatic neutron flux of 8 × 104 n cm-2 s-1 with monochromatization Δλ/λ = 0.7% and angular divergence Δα = 0.2 mrad. The instrument includes both single and position sensitive detectors. The position sensitive detector allows simultaneous measurement of specular reflection and off-specular scattering. Polarization analysis for both specular reflection and off-specular scattering is achieved using either mirror analyzers or a 3He spin filter cell. High efficiency detectors, low background, and high flux provides a dynamic range of up to seven decades in reflectivity. Detailed specifications and the instrument capabilities are illustrated with examples of recently collected data in the fields of thin film magnetism and thin polymer films.
SuperADAM: upgraded polarized neutron reflectometer at the Institut Laue-Langevin.
Devishvili, A; Zhernenkov, K; Dennison, A J C; Toperverg, B P; Wolff, M; Hjörvarsson, B; Zabel, H
2013-02-01
A new neutron reflectometer SuperADAM has recently been built and commissioned at the Institut Laue-Langevin, Grenoble, France. It replaces the previous neutron reflectometer ADAM. The new instrument uses a solid state polarizer/wavelength filter providing a highly polarized (up to 98.6%) monochromatic neutron flux of 8 × 10(4) n cm(-2) s(-1) with monochromatization Δλ∕λ = 0.7% and angular divergence Δα = 0.2 mrad. The instrument includes both single and position sensitive detectors. The position sensitive detector allows simultaneous measurement of specular reflection and off-specular scattering. Polarization analysis for both specular reflection and off-specular scattering is achieved using either mirror analyzers or a (3)He spin filter cell. High efficiency detectors, low background, and high flux provides a dynamic range of up to seven decades in reflectivity. Detailed specifications and the instrument capabilities are illustrated with examples of recently collected data in the fields of thin film magnetism and thin polymer films.
NASA Astrophysics Data System (ADS)
Sun, Tianyi; Guo, Chuanfei; Kempa, Krzysztof; Ren, Zhifeng
2014-03-01
A Fabry-Perot reflection filter, consisting of semi-transparent metal and dielectric layers on opaque metals, is featured by selective absorption determined by the phase difference of waves from the two interfaces. In such systems, semi-transparency is usually realized by layers of reflective metals thinner than the penetration depth of the light. Here we present a filter cavity with entry windows not made of traditional thin layers, but of aperiodic metallic random nanomeshes thicker than the penetration depth, fabricated by grain boundary lithography. It is shown that due to the deteriorated phase caused by the interface between the random nanomesh and the dielectric layer, the width and location of the resonances can be tuned by metallic coverage. Further experiments show that this phenomenon can be used in designing aperiodic plasmonic metamaterial structures for visible and infrared applications.
Imaging alpha particle detector
Anderson, David F.
1985-01-01
A method and apparatus for detecting and imaging alpha particles sources is described. A conducting coated high voltage electrode (1) and a tungsten wire grid (2) constitute a diode configuration discharge generator for electrons dislodged from atoms or molecules located in between these electrodes when struck by alpha particles from a source (3) to be quantitatively or qualitatively analyzed. A thin polyester film window (4) allows the alpha particles to pass into the gas enclosure and the combination of the glass electrode, grid and window is light transparent such that the details of the source which is imaged with high resolution and sensitivity by the sparks produced can be observed visually as well. The source can be viewed directly, electronically counted or integrated over time using photographic methods. A significant increase in sensitivity over other alpha particle detectors is observed, and the device has very low sensitivity to gamma or beta emissions which might otherwise appear as noise on the alpha particle signal.
Imaging alpha particle detector
Anderson, D.F.
1980-10-29
A method and apparatus for detecting and imaging alpha particles sources is described. A dielectric coated high voltage electrode and a tungsten wire grid constitute a diode configuration discharge generator for electrons dislodged from atoms or molecules located in between these electrodes when struck by alpha particles from a source to be quantitatively or qualitatively analyzed. A thin polyester film window allows the alpha particles to pass into the gas enclosure and the combination of the glass electrode, grid and window is light transparent such that the details of the source which is imaged with high resolution and sensitivity by the sparks produced can be observed visually as well. The source can be viewed directly, electronically counted or integrated over time using photographic methods. A significant increase in sensitivity over other alpha particle detectors is observed, and the device has very low sensitivity to gamma or beta emissions which might otherwise appear as noise on the alpha particle signal.
Advanced Bioinks for 3D Printing: A Materials Science Perspective.
Chimene, David; Lennox, Kimberly K; Kaunas, Roland R; Gaharwar, Akhilesh K
2016-06-01
Advanced bioinks for 3D printing are rationally designed materials intended to improve the functionality of printed scaffolds outside the traditional paradigm of the "biofabrication window". While the biofabrication window paradigm necessitates compromise between suitability for fabrication and ability to accommodate encapsulated cells, recent developments in advanced bioinks have resulted in improved designs for a range of biofabrication platforms without this tradeoff. This has resulted in a new generation of bioinks with high print fidelity, shear-thinning characteristics, and crosslinked scaffolds with high mechanical strength, high cytocompatibility, and the ability to modulate cellular functions. In this review, we describe some of the promising strategies being pursued to achieve these goals, including multimaterial, interpenetrating network, nanocomposite, and supramolecular bioinks. We also provide an overview of current and emerging trends in advanced bioink synthesis and biofabrication, and evaluate the potential applications of these novel biomaterials to clinical use.
Determination of layer ordering using sliding-window Fourier transform of x-ray reflectivity data
NASA Astrophysics Data System (ADS)
Smigiel, E.; Knoll, A.; Broll, N.; Cornet, A.
1998-01-01
X-ray reflectometry allows the determination of the thickness, density and roughness of thin layers on a substrate from several Angstroms to some hundred nanometres. The thickness is determined by simulation with trial-and-error methods after extracting initial values of the layer thicknesses from the result of a classical Fast Fourier Transform (FFT) of the reflectivity data. However, the order information of the layers is lost during classical FFT. The order of the layers has then to be known a priori. In this paper, it will be shown that the order of the layers can be obtained by a sliding-window Fourier transform, the so-called Gabor representation. This joint time-frequency analysis allows the direct determination of the order of the layers and, therefore, the use of a more appropriate starting model for refining simulations. A simulated and a measured example show the interest of this method.
NASA Astrophysics Data System (ADS)
Kupferberg, Lenn C.
1996-03-01
Fourier transform IR [FT-IR] spectrometers have virtually replaced scanned grating IR spectrometers in the commercial market. While FTIR spectrometers have been a boon for the chemist, they present problems for the measurement of transmittance of thick, high-index, high-dispersion, IR windows. Reflection and refraction of light by the windows introduce measurement errors. The principles of the FT-IR spectrometer will be briefly reviewed. The origins of the measurement errors will be discussed. Simple modifications to the operation of commercially available instruments will be presented. These include using strategically placed apertures and the use of collimated vs. focused beams at the sample position. They are essential for removing the effects of reflected light entering the interferometer and limiting the divergence angle of light in the interferometer. The latter minimizes refractive effects and insures consistent underfilling of the detector. Data will be shown from FT-IR spectrometers made by four manufactures and compared to measurements from a dispersive spectrometer.
NASA Technical Reports Server (NTRS)
Craig, Roger A.; Davy, William C.; Whiting, Ellis E.
1994-01-01
This paper describes the techniques developed for measuring stagnation-point radiation in NASA's cancelled Aeroassist Flight Experiment (AFE). It specifies the need for such a measurement; the types and requirements for the needed instruments; the Radiative Heating Experiment (RHE) developed for the AFE; the requirements, design parameters, and performance of the window developed for the RHE; the procedures and summary of the technique; and results of the arc-jet wind tunnel experiment conducted to demonstrate the overall concept. Subjects emphasized are the commercial implications of the knowledge to be gained by this experiment in connection with the Aeroassisted Space Transfer Vehicle (ASTV), the nonequilibrium nature of the radiation, concerns over the contribution of vacuum-ultraviolet radiation to the overall radiation, and the limit on the flight environment of the vehicle imposed by the limitations on the window material. Results show that a technique exists with which the stagnation-point radiation can be measured in flight in an environment of interest to commercial ASTV applications.
Do windows or natural views affect outcomes or costs among patients in ICUs?
Kohn, Rachel; Harhay, Michael O; Cooney, Elizabeth; Small, Dylan S; Halpern, Scott D
2013-07-01
To determine whether potential exposure to natural light via windows or to more pleasing views through windows affects outcomes or costs among critically ill patients. Retrospective cohort study. An academic hospital in Philadelphia, PA. Six thousand one hundred thirty-eight patients admitted to a 24-bed medical ICU and 6,631 patients admitted to a 24-bed surgical ICU from July 1, 2006, to June 30, 2010. Assignment to medical ICU rooms with vs. without windows and to surgical ICU rooms with natural vs. industrial views based on bed availability. In primary analyses adjusting for patient characteristics, medical ICU patients admitted to rooms with (n = 4,093) versus without (n = 2,243) windows did not differ in rates of ICU (p = 0.25) or in-hospital (p = 0.94) mortality, ICU readmissions (p = 0.37), or delirium (p = 0.56). Surgical ICU patients admitted to rooms with natural (n = 3,072) versus industrial (n = 3,588) views experienced slightly shorter ICU lengths of stay and slightly lower variable costs. Instrumental variable analyses based on initial bed assignment and exposure time did not show any differences in any outcomes in either the medical ICU or surgical ICU cohorts, and none of the differences noted in primary analyses remained statistically significant when adjusting for multiple comparisons. In a prespecified subgroup analysis among patients with ICU length of stay greater than 72 hours, MICU windows were associated with reduced ICU (p = 0.02) and hospital mortality (p = 0.04); these results did not meet criteria for significance after adjustment for multiple comparisons. ICU rooms with windows or natural views do not improve outcomes or reduce costs of in-hospital care for general populations of medical and surgical ICU patients. Future work is needed to determine whether targeting light from windows directly toward patients influences outcomes and to explore these effects in patients at high risk for adverse outcomes.
Window contamination on Expose-R
NASA Astrophysics Data System (ADS)
Demets, R.; Bertrand, M.; Bolkhovitinov, A.; Bryson, K.; Colas, C.; Cottin, H.; Dettmann, J.; Ehrenfreund, P.; Elsaesser, A.; Jaramillo, E.; Lebert, M.; van Papendrecht, G.; Pereira, C.; Rohr, T.; Saiagh, K.
2015-01-01
Expose is a multi-user instrument for astrobiological and astrochemical experiments in space. Installed at the outer surface of the International Space Station, it enables investigators to study the impact of the open space environment on biological and biochemical test samples. Two Expose missions have been completed so far, designated as Expose-E (Rabbow et al. 2012) and Expose-R (Rabbow et al. this issue). One of the space-unique environmental factors offered by Expose is full-spectrum, ultraviolet (UV)-rich electromagnetic radiation from the Sun. This paper describes and analyses how on Expose-R, access of the test samples to Solar radiation degraded during space exposure in an unpredicted way. Several windows in front of the Sun-exposed test samples acquired a brown shade, resulting in a reduced transparency in visible light, UV and vacuum UV (VUV). Post-flight investigations revealed the discolouration to be caused by a homogenous film of cross-linked organic polymers at the inside of the windows. The chemical signature varied per sample carrier. No such films were found on windows from sealed, pressurized compartments, or on windows that had been kept out of the Sun. This suggests that volatile compounds originating from the interior of the Expose facility were cross-linked and photo-fixed by Solar irradiation at the rear side of the windows. The origin of the volatiles was not fully identified; most probably there was a variety of sources involved including the biological test samples, adhesives, plastics and printed circuit boards. The outer surface of the windows (pointing into space) was chemically impacted as well, with a probable effect on the transparency in VUV. The reported analysis of the window contamination on Expose-R is expected to help the interpretation of the scientific results and offers possibilities to mitigate this problem on future missions - in particular Expose-R2, the direct successor of Expose-R.
1998-09-30
Optical ports ring the Electrostatic Levitator (ESL) vacuum chamber to admit light from the heating laser (beam passes through the window at left), positioning lasers (one port is at center), and lamps to allow diagnostic instruments to view the sample. The ESL uses static electricity to suspend an object (about 2-3 mm in diameter) inside a vacuum chamber while a laser heats the sample until it melts. This lets scientists record a wide range of physical properties without the sample contacting the container or any instruments, conditions that would alter the readings. The Electrostatic Levitator is one of several tools used in NASA's microgravity materials science program.
Surface Imaging Skin Friction Instrument and Method
NASA Technical Reports Server (NTRS)
Brown, James L. (Inventor); Naughton, Jonathan W. (Inventor)
1999-01-01
A surface imaging skin friction instrument allowing 2D resolution of spatial image by a 2D Hilbert transform and 2D inverse thin-oil film solver, providing an innovation over prior art single point approaches. Incoherent, monochromatic light source can be used. The invention provides accurate, easy to use, economical measurement of larger regions of surface shear stress in a single test.
Novel approaches to the construction of miniaturized analytical instrumentation
NASA Technical Reports Server (NTRS)
Porter, Marc D.; Otoole, Ronald P.; Coldiron, Shelley J.; Deninger, William D.; Deinhammer, Randall S.; Burns, Stanley G.; Bastiaans, Glenn J.; Braymen, Steve D.; Shanks, Howard R.
1992-01-01
This paper focuses on the design, construction, preliminary testing, and potential applications of three forms of miniaturized analytical instrumentation. The first is an optical fiber instrument for monitoring pH and other cations in aqueous solutions. The instrument couples chemically selective indicators that were immobilized at porous polymeric films with a hardware package that provides the excitation light source, required optical components, and detection and data processing hardware. The second is a new form of a piezoelectric mass sensor. The sensor was fabricated by the deposition of a thin (5.5 micron) film of piezoelectric aluminum nitride (AIN). The completed deposition process yields a thin film resonator (TFR) that is shaped as a 400 micron square and supports a standing bulk acoustic wave in a longitudinal mode at frequencies of approx. 1 GHz. Various deposition and vapor sorption studies indicate that the mass sensitivity of the TFR's rival those of the most sensitive mass sensors currently available, though offering such performance in a markedly smaller device. The third couples a novel form of liquid chromatography with microlithographic miniaturization techniques. The status of the miniaturization effort, the goal of which is to achieve chip-scale separations, is briefly discussed.
Use of UV-protective windows and window films to aid in the prevention of skin cancer.
Edlich, Richard F; Winters, Kathryne L; Cox, Mary Jude; Becker, Daniel G; Horowitz, Jed H; Nichter, Larry S; Britt, L D; Long, William B; Edlic, Elizabeth C
2004-01-01
People are exposed to ambient solar ultraviolet (UV) radiation throughout their daily routine, intentionally and unintentionally. Cumulative and excessive exposure to UV radiation is the behavioral cause to skin cancers, skin damage, premature skin aging, and sun-related eye disorders. More than one million new cases of skin cancer were diagnosed in the United States this year. UV radiates directly and diffusely scattered by the various environmental and atmospheric conditions and has access to the skin from all directions. Because of this diffuse UV radiation, a person situated under a covering, such as the roof of a car or house, is not completely protected from the sun's rays. Because shade structures do not protect effectively against UV radiation, there have been major advances in photoprotection of glass by the development of specially designed photoprotective windows and films. It is the purpose of this collective review to highlight the photoprotective windows and films that should be incorporated into residential, commercial, and school glass windows to reduce sun exposure. Low-emittence (low-E) coatings are microscopically thin, virtually invisible, metal or metallic oxide layers deposited on a window or skylight glazing surface to reduce the U-factor by suppressing radiative heat flow as well as to limit UV radiation. The exclusive Thermaflect coating uses the most advanced, double-layer soft coat technology to continue to deliver top performance for UV protection as well as prevent heat loss in the home. This product blocks 87% of UV radiation and has an Energy Star certification in all climate zones. Tints and films have been another important advance in glass photoprotection, especially in automobiles. Quality widow film products are high-tech laminates of polyester and metallized coatings bonded by distortion-free adhesives. The International Window Film Association provides members with accreditation in solar control films, safety films, and automotive films in an effort to increase consumer awareness and demand for all professionally installed film window products. The Skin Cancer Foundation has also played a leadership role in certifying window films that limit UV transmission. The Panorama Designer and Safety Films are currently recommended for UV photoprotection by The Skin Cancer Foundation. On the basis of these innovative scientific and industrial advances in window and film photoprotective products, we recommend that they be used in all residential, commercial, and school facilities to provide photoprotection in an effort to reduce skin cancer.
2012-08-16
This patch represents the essential elements associated with pressurized Earth science research aboard the International Space Station. At the top of the patch Klingon script spells out the acronym WORF making reference to the famed Star Trek character of the same name. In doing so it attests to the foresight, honor, integrity, and persistence of all those who made the WORF possible. To the right of the Klingon script is a single four pointed star in the form of a cross to honor the late Dr. Jack Estes and Dr. Dave Amsbury, the individuals most responsible for seeing to it that an optical quality, Earth science research window was added to the United States laboratory module, Destiny. The "flying eyeball" represents the ability of the ISS to allow scientists and astronauts to make and record continuous observations of natural and manmade processes on the surface of the Earth. The Destiny laboratory is depicted on the right of the patch above the Flag of the United States of America and highlights the position of the nadir looking, optical quality, science window in the module. The light emanating from the window from the lighted interior of the module appropriately illuminates the National Ensign for display during both day and night time. In the center of the patch, below the flying eyeball is a graphic representation of the WORF rack. A science instrument is mounted on the WORF payload shelf and is recording data of the Earth's surface through the nadir looking, science window over which the WORF rack is mounted. An astronaut represented by Mario Runco Jr., a designer, developer, and manager of the WORF and depicted as Star Trek's Mr. Spock, is to the left of the WORF rack and is shown in his flight suit with his STS-44 mission patch operating an imaging instrument, emphasizing the importance of astronaut participation to achieve the maximum scientific return from orbital research.
Global Measurements of Optically Thin Cirrus Clouds Using CALIOP
NASA Astrophysics Data System (ADS)
Ryan, R. A.; Avery, M. A.; Vaughan, M.
2017-12-01
Optically thin cirrus clouds, defined here as cold clouds consisting of randomly oriented ice crystals and having optical depths (τ) less than 0.3, are difficult to measure accurately. Thin cirrus clouds have been shown to have a net warming effect on the globe but, because passive instruments are not sensitive to optically thin clouds, the occurrence frequency of thin cirrus is greatly underestimated in historical passive sensor cloud climatology. One major strength of Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) is its ability to detect these thin cirrus clouds, thus filling an important missing piece in the historical data record. This poster examines multiple years of CALIOP Level 2 data, focusing on those CALIOP retrievals identified as being optically thin (τ < 0.3), having a cold centroid temperature (TC < -40°C), and consisting solely of randomly oriented ice crystals. Using this definition, thin cirrus are identified and counted globally within each season. By examining the spatial, and seasonal distributions of these thin clouds we hope to gain a better understanding of how thin cirrus affect the atmosphere. Understanding when and where these clouds form and persist in the global atmosphere is the topic and focus of the presented poster.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-28
... System, 114 Theft Protection, 116 Motor Vehicle Brake Fluids, 118 Power-Operated Window, Partition, and...: Replacement of the instrument cluster with a U.S.-model component with inscription of the word ``brake'' on the brake failure warning light as well as reading speed in mph. Standard No. 108 Lamps, Reflective...
Ambient-Light Simulator For Testing Cockpit Displays
NASA Technical Reports Server (NTRS)
Batson, Vernon M.; Gupton, Lawrence E.
1995-01-01
Apparatus provides illumination from outside, through windows and into interior of simulated airplane cockpit. Simulates sunlight, darkness, or lightning on demand. Ambient-lighting simulator surrounds forward section of simulated airplane. Provides control over intensity, color, and diffuseness of solar illumination and of position of Sun relative to airplane. Used to evaluate aircraft-instrumentation display devices under realistic lighting conditions.
Laurenti, Marco; Bianco, Stefano; Castellino, Micaela; Garino, Nadia; Virga, Alessandro; Pirri, Candido F; Mandracci, Pietro
2016-03-01
Plastic smart windows are becoming one of the key elements in view of the fabrication of inexpensive, lightweight electrochromic (EC) devices to be integrated in the new generation of high-energy-efficiency buildings and automotive applications. However, fabricating electrochromic devices on polymer substrates requires a reduction of process temperature, so in this work we focus on the development of a completely room-temperature deposition process aimed at the preparation of ITO-coated polycarbonate (PC) structures acting as transparent and conductive plastic supports. Without providing any substrate heating or surface activation pretreatments of the polymer, different deposition conditions are used for growing indium tin oxide (ITO) thin films by the radiofrequency magnetron sputtering technique. According to the characterization results, the set of optimal deposition parameters is selected to deposit ITO electrodes having high optical transmittance in the visible range (∼90%) together with low sheet resistance (∼8 ohm/sq). The as-prepared ITO/PC structures are then successfully tested as conductive supports for the fabrication of plastic smart windows. To this purpose, tungsten trioxide thin films are deposited by the reactive sputtering technique on the ITO/PC structures, and the resulting single electrode EC devices are characterized by chronoamperometric experiments and cyclic voltammetry. The fast switching response between colored and bleached states, together with the stability and reversibility of their electrochromic behavior after several cycling tests, are considered to be representative of the high quality of the EC film but especially of the ITO electrode. Indeed, even if no adhesion promoters, additional surface activation pretreatments, or substrate heating were used to promote the mechanical adhesion among the electrode and the PC surface, the observed EC response confirmed that the developed materials can be successfully employed for the fabrication of lightweight and inexpensive plastic EC devices.
NASA Astrophysics Data System (ADS)
Cheng, Z.; Chen, Y.; Liu, Y.; Liu, W.; Zhang, G.
2015-12-01
Among those hydrocarbon reservoir detection techniques, the time-frequency analysis based approach is one of the most widely used approaches because of its straightforward indication of low-frequency anomalies from the time-frequency maps, that is to say, the low-frequency bright spots usually indicate the potential hydrocarbon reservoirs. The time-frequency analysis based approach is easy to implement, and more importantly, is usually of high fidelity in reservoir prediction, compared with the state-of-the-art approaches, and thus is of great interest to petroleum geologists, geophysicists, and reservoir engineers. The S transform has been frequently used in obtaining the time-frequency maps because of its better performance in controlling the compromise between the time and frequency resolutions than the alternatives, such as the short-time Fourier transform, Gabor transform, and continuous wavelet transform. The window function used in the majority of previous S transform applications is the symmetric Gaussian window. However, one problem with the symmetric Gaussian window is the degradation of time resolution in the time-frequency map due to the long front taper. In our study, a bi-Gaussian S transform that substitutes the symmetric Gaussian window with an asymmetry bi-Gaussian window is proposed to analyze the multi-channel seismic data in order to predict hydrocarbon reservoirs. The bi-Gaussian window introduces asymmetry in the resultant time-frequency spectrum, with time resolution better in the front direction, as compared with the back direction. It is the first time that the bi-Gaussian S transform is used for analyzing multi-channel post-stack seismic data in order to predict hydrocarbon reservoirs since its invention in 2003. The superiority of the bi-Gaussian S transform over traditional S transform is tested on a real land seismic data example. The performance shows that the enhanced temporal resolution can help us depict more clearly the edge of the hydrocarbon reservoir, especially when the thickness of the reservoir is small (such as the thin beds).
DOE Office of Scientific and Technical Information (OSTI.GOV)
B. R. Marshall
Spectral reflectance was used to determine the thickness of thin glue layers in a study of the effect of the glue on radiance and reflectance measurements of shocked-tin substrates attached to lithium fluoride windows. Measurements based on profilometry of the components were found to be inaccurate due to flatness variations and deformation of the tin substrate under pressure during the gluing process. The accuracy of the spectral reflectance measurements were estimated to be ±0.5 μm, which was sufficient to demonstrate a convincing correlation between glue thickness and shock-generated light.
Antiproton Studies in Penning Traps
1993-09-30
applications to MRI imaging. This is by far the most sensitive test of CPT invariance with a baryon system and is one of the most accurate tests of CPT...system which has likely applications to MRI imaging. This is by far the most sensitive test of CPT invariance with a baryon system and is one of the...a thin window of matter . In a second 24 hour demonstration experiment, we managed to capture a few antiprotons in the small volume of an ion trap.1
Efficient Broadband Terahertz Radiation Detectors Based on Bolometers with a Thin Metal Absorber
NASA Astrophysics Data System (ADS)
Dem'yanenko, M. A.
2018-01-01
The matrix method has been used to calculate the coefficients of absorption of terahertz radiation in conventional (with radiation incident from vacuum adjacent to the bolometer) and inverted (with radiation incident from the substrate on which the bolometer was fabricated) bolometric structures. Near-unity absorption coefficients were obtained when an additional cavity in the form of a gap between the bolometer and the input or output window was introduced. Conventional bolometers then became narrowband, while inverted-type devices remained broadband.
Ultracold Mixtures of Rubidium and Ytterbium for Open Quantum System Engineering
2014-06-01
was replaced with a standard nipple since the actual thermal conduction is comparable. Second, the collimation tube (5 mm ID x 15 cm length) was...Presumably, there is some sort of thin layer coating the Yb which must first be driven off. The helium buffer gas serves to shorten the mean free...path below the line-of-sight distance to the windows, and we can leave them at room temperature without coating them with Yb. The buffer gas causes
Thermal Loading of Thin Metal Foils Used as Electron Beam Windows for a KRF Laser
2005-06-01
the Inertial Fusion Energy (IFE) requirements for durability, efficiency, and cost. One of the challenging laser components is the pressure foil that...R. Welch, D. V. Rose, and S. Searles, "Electron beam pumped krypton fluoride lasers for fusion energy ," Proc. IEEE, vol. 92, pp. 1043-1056, July...D. Weidenheimer, and D. V. Rose, "Repetitively pulsed, high energy KrF lasers for inertial fusion energy ," Nucl. Fusion, vol. 44, pp. S247-S253
Fiber optic interferometry for industrial process monitoring and control applications
NASA Astrophysics Data System (ADS)
Marcus, Michael A.
2002-02-01
Over the past few years we have been developing applications for a high-resolution (sub-micron accuracy) fiber optic coupled dual Michelson interferometer-based instrument. It is being utilized in a variety of applications including monitoring liquid layer thickness uniformity on coating hoppers, film base thickness uniformity measurement, digital camera focus assessment, optical cell path length assessment and imager and wafer surface profile mapping. The instrument includes both coherent and non-coherent light sources, custom application dependent optical probes and sample interfaces, a Michelson interferometer, custom electronics, a Pentium-based PC with data acquisition cards and LabWindows CVI or LabView based application specific software. This paper describes the development evolution of this instrument platform and applications highlighting robust instrument design, hardware, software, and user interfaces development. The talk concludes with a discussion of a new high-speed instrument configuration, which can be utilized for high speed surface profiling and as an on-line web thickness gauge.
NASA Astrophysics Data System (ADS)
Moser, Matthew Lee
Since their discovery two decades ago, single walled carbon nanotubes (SWNT) have created an expansion of scientific interest that continues to grow to this day. This is due to a good balance between presence of bandgap, chemical reactivity and electrical conductivity. By interconnection of the individual nanotubes or modulation of the SWNT's electronic states, electronic devices made with thin films can become candidates for next generation electronics in areas such as memory devices, spintronics, energy storage devices and optoelectronics. My thesis focuses on the modulation of the electronic structure, optical properties and transport characteristics of single walled carbon nanotube films and their application in electronic and optoelectronic devices. Individual SWNTs have exceptional electronic properties but are difficult to manipulate for use in electronic devices. Alternatively, devices utilize SWNTs in thin films. SWNT thin films, however, may lose some of the properties due to Schottky barriers and electron hoping between metal-nanotube junctions and individual nanotubes within the film, respectively. Until recently, there has been no known route to preserve both conjugation and electrical properties. Prior attempts using covalent chemical functionalization led to re-hybridization of sp2 carbon centers to sp3, which introduces defects into the material and results in a decrease of electron mobility. As was discovered in Haddon Research group, depositing Group VI transition metals via atomic vapor deposition into SWNT films results in formation of bis-hexahapto covalent bonds. This (eta6-SWNT) Metal (eta6-SWNT) type of bonding was found to interconnect the delocalized systems without inducing structural re-hybridization and results in a decrease of the thin films electrical resistance. Recently, with the assistance of electron beam deposition, we deposited atomic metal vapor of various lanthanide metals on the SWNT thin films with the idea that they would also form covalent interconnects between nanotube sidewalls. In the case of highly electropositive lanthanides, the possibility of hexahapto bonding combined with ionic character can be evaluated and theorized. We have reported the first use of lanthanides to enhance the conductivities of SWNT thin films and showed that these metals can not only form bis-hexahapto interconnects at the SWNT junctions but can also inject electrons into the conduction bands of the SWNTs, forming a new type of mixed covalent-ionic bonding in the SWNT network. By monitoring electrical resistance and taking spectroscopic measurements of the Near-Infrared region we are able to show the correlation between enhanced conductivity and suppression of the S 11 interband transition of semiconducting SWNTs. Potential applications of SWNT thin films as electrochromic windows require reversible modulation of the electronic structure. In order to fabricate SWNTs devices which allow for this behavior it is necessary to modulate the electronic structure by physical means such as the application of an electrical potential. We found that ionic solutions can assist with maintaining complete suppression of two Van Hove singularities in the Density of States of semiconducting SWNTs which results in optically transparent windows in the Near-Infrared region, similar to the effect seen with the incorporation of atomic lanthanide metals in thin films. We demonstrate this behavior to provide a route to nanotube based optoelectronic devices in which we use electric fields to reversibly dope the SWNT films and thereby achieve controllable modulation of optical properties of SWNT thin film.
Fan, Ching-Lin; Lin, Wei-Chun; Chang, Hsiang-Sheng; Lin, Yu-Zuo; Huang, Bohr-Ran
2016-01-01
In this paper, the top-contact (TC) pentacene-based organic thin-film transistor (OTFT) with a tetrafluorotetracyanoquinodimethane (F4TCNQ)-doped pentacene interlayer between the source/drain electrodes and the pentacene channel layer were fabricated using the co-evaporation method. Compared with a pentacene-based OTFT without an interlayer, OTFTs with an F4TCNQ:pentacene ratio of 1:1 showed considerably improved electrical characteristics. In addition, the dependence of the OTFT performance on the thickness of the F4TCNQ-doped pentacene interlayer is weaker than that on a Teflon interlayer. Therefore, a molecular doping-type F4TCNQ-doped pentacene interlayer is a suitable carrier injection layer that can improve the TC-OTFT performance and facilitate obtaining a stable process window. PMID:28787845
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bartholomew M. J.; Reynolds, R. M.; Vogelmann, A. M.
2011-11-01
The design and operation of a Thin-Cloud Rotating Shadowband Radiometer (TCRSR) described here was used to measure the radiative intensity of the solar aureole and enable the simultaneous retrieval of cloud optical depth, drop effective radius, and liquid water path. The instrument consists of photodiode sensors positioned beneath two narrow metal bands that occult the sun by moving alternately from horizon to horizon. Measurements from the narrowband 415-nm channel were used to demonstrate a retrieval of the cloud properties of interest. With the proven operation of the relatively inexpensive TCRSR instrument, its usefulness for retrieving aerosol properties under cloud-free skiesmore » and for ship-based observations is discussed.« less
Choi, Jongsoo; Duan, Xiyu; Li, Haijun; Wang, Thomas D; Oldham, Kenn R
2017-10-01
Use of a thin-film piezoelectric microactuator for axial scanning during multi-photon vertical cross-sectional imaging is described. The actuator uses thin-film lead-zirconate-titanate (PZT) to generate upward displacement of a central mirror platform, micro-machined from a silicon-on-insulator (SOI) wafer to dimensions compatible with endoscopic imaging instruments. Device modeling in this paper focuses on existence of frequencies near device resonance producing vertical motion with minimal off-axis tilt even in the presence of multiple vibration modes and non-uniformity in fabrication outcomes. Operation near rear resonance permits large stroke lengths at low voltages relative to other vertical microactuators. Highly uniform vertical motion of the mirror platform is a key requirement for vertical cross-sectional imaging in the remote scan architecture being used for multi-photon instrument prototyping. The stage is installed in a benchtop testbed in combination with an electrostatic mirror that performs in-plane scanning. Vertical sectional images are acquired from 15 μm diameter beads and excised mouse colon tissue.
2003-03-17
KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, workers align the Rover Equipment Deck (RED) on one of the Mars Exploration Rovers (MER) with the Warm Electronics Box (WEB). Processing of the rovers, plus cruise stage, lander and heat shield elements, is ongoing. Set to launch in 2003, the MER Mission will consist of two identical rovers designed to cover roughly 110 yards each Martian day. Each rover will carry five scientific instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past. The rovers will be identical to each other, but will land at different regions of Mars. The first rover has a launch window opening May 30, and the second rover a window opening June 25, 2003.
Quasi-Elastic Light Scattering in Ophthalmology
NASA Astrophysics Data System (ADS)
Ansari, Rafat R.
The eye is not just a "window to the soul"; it can also be a "window to the human body." The eye is built like a camera. Light which travels from the cornea to the retina traverses through tissues that are representative of nearly every tissue type and fluid type in the human body. Therefore, it is possible to diagnose ocular and systemic diseases through the eye. Quasi-elastic light scattering (QELS) also known as dynamic light scattering (DLS) is a laboratory technique routinely used in the characterization of macromolecular dispersions. QELS instrumentation has now become more compact, sensitive, flexible, and easy to use. These developments have made QELS/DLS an important tool in ophthalmic research where disease can be detected early and noninvasively before the clinical symptoms appear.
Automated Liquid-Level Control of a Nutrient Reservoir for a Hydroponic System
NASA Technical Reports Server (NTRS)
Smith, Boris; Asumadu, Johnson A.; Dogan, Numan S.
1997-01-01
A microprocessor-based system for control of the liquid level of a nutrient reservoir for a plant hydroponic growing system has been developed. The system uses an ultrasonic transducer to sense the liquid level or height. A National Instruments' Multifunction Analog and Digital Input/Output PC Kit includes NI-DAQ DOS/Windows driver software for an IBM 486 personal computer. A Labview Full Development system for Windows is the graphical programming system being used. The system allows liquid level control to within 0.1 cm for all levels tried between 8 and 36 cm in the hydroponic system application. The detailed algorithms have been developed and a fully automated microprocessor based nutrient replenishment system has been described for this hydroponic system.
NASA Astrophysics Data System (ADS)
Guo, Y. N.; Wei, D. Y.; Xiao, S. Q.; Huang, S. Y.; Zhou, H. P.; Xu, S.
2013-05-01
Hydrogenated microcrystalline silicon (μc-Si:H) thin films were prepared by remote low frequency inductively coupled plasma (ICP) chemical vapor deposition system, and the effect of silane/hydrogen ratio on the microstructure and electrical properties of μc-Si:H films was systematically investigated. As silane/hydrogen ratio increases, the crystalline volume fraction Fc decreases and the ratio of the intensity of (220) peak to that of (111) peak drops as silane flow rate is increased. The FTIR result indicates that the μc-Si:H films prepared by remote ICP have a high optical response with a low hydrogen content, which is in favor of reducing light-induced degradation effect. Furthermore, the processing window of the phase transition region for remote ICP is much wider than that for typical ICP. The photosensitivity of μc-Si:H films can exceed 100 at the transition region and this ensures the possibility of the fabrication of microcrystalline silicon thin film solar cells with a open-circuit voltage of about 700 mV.
Cadmium sulfide thin films growth by chemical bath deposition
NASA Astrophysics Data System (ADS)
Hariech, S.; Aida, M. S.; Bougdira, J.; Belmahi, M.; Medjahdi, G.; Genève, D.; Attaf, N.; Rinnert, H.
2018-03-01
Cadmium sulfide (CdS) thin films have been prepared by a simple technique such as chemical bath deposition (CBD). A set of samples CdS were deposited on glass substrates by varying the bath temperature from 55 to 75 °C at fixed deposition time (25 min) in order to investigate the effect of deposition temperature on CdS films physical properties. The determination of growth activation energy suggests that at low temperature CdS film growth is governed by the release of Cd2+ ions in the solution. The structural characterization indicated that the CdS films structure is cubic or hexagonal with preferential orientation along the direction (111) or (002), respectively. The optical characterization indicated that the films have a fairly high transparency, which varies between 55% and 80% in the visible range of the optical spectrum, the refractive index varies from 1.85 to 2.5 and the optical gap value of which can reach 2.2 eV. It can be suggested that these properties make these films perfectly suitable for their use as window film in thin films based solar cells.
NASA Astrophysics Data System (ADS)
Madiba, I. G.; Kotsedi, L.; Ngom, B. D.; Khanyile, B. S.; Maaza, M.
2018-05-01
Vanadium dioxide films have been known as the most promising thermochromic thin films for smart windows which self-control the solar radiation and heat transfer for energy saving, comfort in houses and automotives. Such an attractive technological application is due to the fact that vanadium dioxide crystals exhibit a fast semiconductor-to-metal phase transition at a transition temperature Tc of about 68 °C, together with sharp optical changes from high transmitive to high reflective coatings in the IR spectral region. The phase transition has been associated with the nature of the microstructure, stoichiometry and stresses related to the oxide. This study reports on the effect of the crystallographic quality controlled by the substrate temperature on the thermochromic properties of vanadium dioxide thin films synthesized by reactive radio frequency inverted cylindrical magnetron sputtering from vanadium target. The reports results are based on X-ray diffraction, Atomic force microscopy, and UV-Visible spectrophotometer. The average crystalline grain size of VO2 increases with the substrate temperature, inducing stress related phenomena within the films.
Liu, Suilin; Wu, Zhiheng; Zhang, Yake; Yao, Zhiqiang; Fan, Jiajie; Zhang, Yiqiang; Hu, Junhua; Zhang, Peng; Shao, Guosheng
2015-01-07
We report here a reliable and reproducible single-step (without post-annealing) fabrication of phase-pure p-type rhombohedral CuAlO2 (r-CuAlO2) thin films by reactive magnetron sputtering. The dependence of crystallinity and phase compositions of the films on the growth temperature was investigated, revealing that highly-crystallized r-CuAlO2 thin films could be in situ grown in a narrow temperature window of ∼940 °C. Optical and electrical property studies demonstrate that (i) the films are transparent in the visible light region, and the bandgaps of the films increased to ∼3.86 eV with the improvement of crystallinity; (ii) the conductance increased by four orders of magnitude as the film was evolved from the amorphous-like to crystalline structure. The predominant role of crystallinity in determining CuAlO2 film properties was demonstrated to be due to the heavy anisotropic characteristics of the O 2p-Cu 3d hybridized valence orbitals.
Hermannsdörfer, Justus; de Jonge, Niels
2017-02-05
Samples fully embedded in liquid can be studied at a nanoscale spatial resolution with Scanning Transmission Electron Microscopy (STEM) using a microfluidic chamber assembled in the specimen holder for Transmission Electron Microscopy (TEM) and STEM. The microfluidic system consists of two silicon microchips supporting thin Silicon Nitride (SiN) membrane windows. This article describes the basic steps of sample loading and data acquisition. Most important of all is to ensure that the liquid compartment is correctly assembled, thus providing a thin liquid layer and a vacuum seal. This protocol also includes a number of tests necessary to perform during sample loading in order to ensure correct assembly. Once the sample is loaded in the electron microscope, the liquid thickness needs to be measured. Incorrect assembly may result in a too-thick liquid, while a too-thin liquid may indicate the absence of liquid, such as when a bubble is formed. Finally, the protocol explains how images are taken and how dynamic processes can be studied. A sample containing AuNPs is imaged both in pure water and in saline.