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Sample records for pumped uv converter

  1. Single-mode, All-Solid-State Nd:YAG Laser Pumped UV Converter

    NASA Technical Reports Server (NTRS)

    Prasad, Narasimha S.; Armstrong, Darrell, J.; Edwards, William C.; Singh, Upendra N.

    2008-01-01

    In this paper, the status of a high-energy, all solid-state Nd:YAG laser pumped nonlinear optics based UV converter development is discussed. The high-energy UV transmitter technology is being developed for ozone sensing applications from space based platforms using differential lidar technique. The goal is to generate greater than 200 mJ/pulse with 10-50 Hz PRF at wavelengths of 308 nm and 320 nm. A diode-pumped, all-solid-state and single longitudinal mode Nd:YAG laser designed to provide conductively cooled operation at 1064 nm has been built and tested. Currently, this pump laser provides an output pulse energy of >1 J/pulse at 50 Hz PRF and a pulsewidth of 22 ns with an electrical-to-optical system efficiency of greater than 7% and a M(sup 2) value of <2. The single frequency UV converter arrangement basically consists of an IR Optical Parametric Oscillator (OPO) and a Sum Frequency Generator (SFG) setups that are pumped by 532 nm wavelength obtained via Second Harmonic Generation (SHG). In this paper, the operation of an inter cavity SFG with CW laser seeding scheme generating 320 nm wavelength is presented. Efforts are underway to improve conversion efficiency of this mJ class UV converter by modifying the spatial beam profile of the pump laser.

  2. Charge-pump voltage converter

    DOEpatents

    Brainard, John P.; Christenson, Todd R.

    2009-11-03

    A charge-pump voltage converter for converting a low voltage provided by a low-voltage source to a higher voltage. Charge is inductively generated on a transfer rotor electrode during its transit past an inductor stator electrode and subsequently transferred by the rotating rotor to a collector stator electrode for storage or use. Repetition of the charge transfer process leads to a build-up of voltage on a charge-receiving device. Connection of multiple charge-pump voltage converters in series can generate higher voltages, and connection of multiple charge-pump voltage converters in parallel can generate higher currents. Microelectromechanical (MEMS) embodiments of this invention provide a small and compact high-voltage (several hundred V) voltage source starting with a few-V initial voltage source. The microscale size of many embodiments of this invention make it ideally suited for MEMS- and other micro-applications where integration of the voltage or charge source in a small package is highly desirable.

  3. Photovoltaic converters for solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Walker, Gilbert H.; Heinbockel, John H.

    1988-01-01

    The authors describe a mathematical parametric study of converters used to convert laser radiation to electricity for space-based laser power systems. Two different lasers, the 1.06-micron Nd laser and the 1.315-micron iodine laser, are used in the vertical junction converter. The calculated efficiency is 50 percent for a 100-junction Si photovoltaic converter when used with a Nd laser. The calculated efficiency for a 1000-junction Ga(0.53)In(0.47)As photovoltaic converter is 43 percent when used with an iodine laser.

  4. A compact Raman converter for UV-VIS spectrometers

    NASA Astrophysics Data System (ADS)

    Bisson, Patrick J.; Whitten, James E.

    2015-05-01

    A small form factor, easily constructed converter that adapts fiber coupled UV/VIS CCD detector-based spectrometers into a right angle scattering Raman spectrometer is described. Its design philosophy and design are discussed. An example measurement, the depolarization ratio of carbon tetrachloride, a classic Raman test compound, is presented. The unique instrument features a blue-violet (405 nm wavelength) diode laser that takes advantage of the inverse fourth power wavelength dependence of Raman scattering. The converter also features Glan-Thompson polarizing prisms that enable measurement of depolarization ratios. The spectrometer is also capable of measuring a standard Raman spectrum. A fiber optic link offers flexibility when adapting the converter to any spectrometer system that accepts a fiber optic input. The performance of the instrument is critically discussed in the context of an example measurement.

  5. A compact Raman converter for UV-VIS spectrometers.

    PubMed

    Bisson, Patrick J; Whitten, James E

    2015-05-01

    A small form factor, easily constructed converter that adapts fiber coupled UV/VIS CCD detector-based spectrometers into a right angle scattering Raman spectrometer is described. Its design philosophy and design are discussed. An example measurement, the depolarization ratio of carbon tetrachloride, a classic Raman test compound, is presented. The unique instrument features a blue-violet (405 nm wavelength) diode laser that takes advantage of the inverse fourth power wavelength dependence of Raman scattering. The converter also features Glan-Thompson polarizing prisms that enable measurement of depolarization ratios. The spectrometer is also capable of measuring a standard Raman spectrum. A fiber optic link offers flexibility when adapting the converter to any spectrometer system that accepts a fiber optic input. The performance of the instrument is critically discussed in the context of an example measurement. PMID:26026558

  6. Improvement of photovoltaic pumping systems based on standard frequency converters by means of programmable logic controllers

    SciTech Connect

    Fernandez-Ramos, Jose; Narvarte-Fernandez, Luis; Poza-Saura, Fernando

    2010-01-15

    Photovoltaic pumping systems (PVPS) based on standard frequency converters (SFCs) are currently experiencing a growing interest in pumping programmes implemented in remote areas because of their high performance in terms of component reliability, low cost, high power range and good availability of components virtually anywhere in the world. However, in practical applications there have appeared a number of problems related to the adaptation of the SFCs to the requirements of the photovoltaic pumping systems (PVPS). Another disadvantage of dedicated PVPS is the difficulty in implementing maximum power point tracking (MPPT). This paper shows that these problems can be solved through the addition of a basic industrial programmable logic controller (PLC) to the system. This PLC does not increase the cost and complexity of the system, but improves the adaptation of the SFC to the photovoltaic pumping system, and increases the overall performance of the system. (author)

  7. Airborne-mercury detection by resonant UV laser pumping.

    PubMed

    Bahns, J T; Lynds, L; Stwalley, W C; Simmons, V; Robinson, T; Bililign, S

    1997-05-15

    Optical pumping of the Hg(0) (6s (1)S(0) --> 6p (3)P(1)) transition at 253.7 nm (in air) leads to extremely fast energy transfer and strong laser-induced-fluorescence (LIF) from the Hg(0) (7s(3)S(1) --> 6p (3)P(2)) green transition at 546.2 nm, which is not directly populated by the laser. Ionization occurs simultaneously and becomes particularly strong at reduced background pressures. These observations are consistent with the existence of a multiphoton process followed by electron collisional excitation. Preliminary studies are made to evaluate these phenomena for detecting elemental airborne mercury by LIF and point monitoring with an ionization detector. Measured sensitivities of 2 and 10 parts in 10(9) (ppb), respectively, at 0.1-Torr air pressure are projected to increase to 1 x 10(-4) and 1 x 10(-5) ppb after relevant system optimization. PMID:18185642

  8. Replacement of the static frequency converter starting equipment at the Raccoon Mountain Pumped Storage Plant

    SciTech Connect

    Patel, G.; Deckman, J.T.

    1995-12-31

    In October 1994, the Tennessee Valley Authority awarded a contract for replacement of their Static Frequency Converter (SFC) Starting Equipment at the Raccoon Mountain Pumped Storage Plant. Replacement of the original SFC was deemed necessary to counter a rising forced outage rate and costly repairs directly attributable to the advanced age and condition of the original equipment. This paper presents a comparison of the features of the new SFC versus the original SFC. The new SFC is scheduled to undergo check-out and testing in Spring of 1996.

  9. 46 CFR 32.52-1 - Bilge pumps on tank vessels constructed or converted on or after November 19, 1952-TB/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Bilge pumps on tank vessels constructed or converted on... Bilge pumps on tank vessels constructed or converted on or after November 19, 1952—TB/ALL. The number and arrangement of bilge pumps on each tank vessel shall conform to the requirements of subchapter...

  10. 46 CFR 32.52-1 - Bilge pumps on tank vessels constructed or converted on or after November 19, 1952-TB/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Bilge pumps on tank vessels constructed or converted on... Bilge pumps on tank vessels constructed or converted on or after November 19, 1952—TB/ALL. The number and arrangement of bilge pumps on each tank vessel shall conform to the requirements of subchapter...

  11. 46 CFR 32.52-1 - Bilge pumps on tank vessels constructed or converted on or after November 19, 1952-TB/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Bilge pumps on tank vessels constructed or converted on... Bilge pumps on tank vessels constructed or converted on or after November 19, 1952—TB/ALL. The number and arrangement of bilge pumps on each tank vessel shall conform to the requirements of subchapter...

  12. 46 CFR 32.52-1 - Bilge pumps on tank vessels constructed or converted on or after November 19, 1952-TB/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Bilge pumps on tank vessels constructed or converted on... Bilge pumps on tank vessels constructed or converted on or after November 19, 1952—TB/ALL. The number and arrangement of bilge pumps on each tank vessel shall conform to the requirements of subchapter...

  13. Diode-pumped solid state laser sources of picosecond UV pulses for photobiology

    NASA Astrophysics Data System (ADS)

    Roisse, Eric; Louradour, Frederic; Couderc, Vincent; Barthelemy, Alain; Gaignet, M.; Balembois, Francois; Georges, Patrick M.; Brun, Alain

    1998-05-01

    We realized three different configurations for the production of picoseconds pulses in the UV by a diode-pumped solid-state laser. The first one is based on a diode-pumped Cr:LiSAF oscillator delivering tunable picosecond pulses in the near infrared. A Ti:Sapphire regenerative amplifier increased IR pulses energy up to 4.5 (mu) J. After doubling and tripling in two LBO crystals, we obtained pulses with an energy up to 0.14 (mu) J tunable between 273 and 286 nm. In the second scheme, based on a modelocked Nd:YAG laser, the SHG (KTP) and SFG (LBO) crystals are both inserted inside the cavity. The laser operated in a Q-switched mode-locked regime and produced 1.2 mW of UV average power in pulse of 60 picoseconds duration and 4 W peak power. In the last architecture, we used a resonant enhancement with a ring- cavity. We obtained 54% conversion efficiency in the green for picoseconds pulses at 1064 nm at 100 MHz rep. rate. A special arrangement was implemented for compensation of the birefringence and walk-off of the KTP crystal in the resonant cavity. Conversion to UV in the same cavity is in progress.

  14. Resonant uv pump-probe spectroscopy of dipicolinic acid via impulsive excitation

    SciTech Connect

    Murawski, Robert K.; Rostovtsev, Yuri V.; Sariyanni, Zoe-Elizabeth; Sautenkov, Vladimir A.; Backus, Sterling; Raymondson, Daisy; Kapteyn, Henry C.; Murnane, Margaret M.; Scully, Marlan O.

    2008-02-15

    We present experimental evidence of coherent wave packet motion in dipicolinic acid (C{sub 7}H{sub 5}NO{sub 4}) which is an important marker molecule for bacterial spores. Resonant impulsive excitation is achieved by applying a uv pump pulse (267 nm, 16 fs) which has a duration that is shorter than the vibrational period of the molecules. The resulting dynamics is then probed with a weaker pulse of the same width and frequency. Evidence of the important 'fingerprint' region for this molecule (between 1000 cm{sup -1} and 1500 cm{sup -1}) is found in the transient absorption of the probe. We present simulations of the pump-probe experiment, based on the Liouville equation for the density matrix, and predict the optimal pulse width and detuning.

  15. UV by the fourth harmonic generation of compact side-pumped Yb:YAG laser emission

    NASA Astrophysics Data System (ADS)

    Cole, Brian; McIntosh, Chris; Hays, Alan; Dilazaro, Tom; Goldberg, Lew

    2016-03-01

    We present a compact, side pumped passively Q-switched Yb:YAG laser that was operated in a burst mode with pump durations of 2-4 ms at low duty cycles. Intra-pump pulse Q-switched pulse repetition frequencies varied from 5-20 kHz depending on the transmission of the Cr:YAG saturable absorber, which was varied from 70% to 94%. Pump duration, pulse repetition frequency and output coupler reflectivity were optimized to yield maximum Yb:YAG laser average power and laser efficiency, while providing sufficient peak intensity, typically 0.3-1 MW, to enable efficient forth harmonic generation (FHG). Pulse energies and durations were in ranges of 0.3-1.8 mJ and 1.5-7ns, respectively, dependent on the unbleached transmission of the Cr:YAG saturable absorber. We achieved an optical efficiency of greater than 15% for the Yb:YAG laser. Extra-cavity 515 nm second harmonic generation (SHG) was achieved using a 5mm long KTP crystal. The 515 nm light was then frequency doubled by focusing it into a 7mm long BBO crystal, resulting in a 15% conversion efficiency from 1030nm to 257.5 nm, with an average UV power greater than 100 mW.

  16. Characterization of attosecond XUV pulses utilizing a broadband UV approximately VUV pumping.

    PubMed

    Chen, Jun; Itakura, Ryuji; Nakajima, Takashi

    2010-02-01

    We propose a simple scheme to characterize attosecond extreme ultraviolet (XUV) pulses. A broadband ultraviolet (UV) approximately vacuum ultraviolet (VUV) pump pulse creates a coherent superposition of atomic bound states, from which photoionization takes place by the time-delayed attosecond XUV probe pulse. Information on the spectral phase of the XUV pulse can be extracted from the phase offset of the interference beating in the photoelectron spectra using a standard SPIDER (spectral phase interferometry for direct electric-field reconstruction) algorithm. We further discuss the influence of the chirp and polychromaticity of the pump pulse, and show that they do not spoil the reconstruction process. Since our scheme is applicable for various simple atoms such as H, He, and Cs, etc., and capable of characterizing attosecond XUV pulses with a pulse duration of a few hundred attoseconds or even less, it can be an alternative technique to characterize attosecond XUV pulses. Specific numerical examples are presented for the H atom utilizing the 2p and 3p states. PMID:20174032

  17. Luminescence- and nanoparticle-mediated increase of light absorption by photoreceptor cells: Converting UV light to visible light

    PubMed Central

    Li, Lei; Sahi, Sunil K.; Peng, Mingying; Lee, Eric B.; Ma, Lun; Wojtowicz, Jennifer L.; Malin, John H.; Chen, Wei

    2016-01-01

    We developed new optic devices – singly-doped luminescence glasses and nanoparticle-coated lenses that convert UV light to visible light – for improvement of visual system functions. Tb3+ or Eu3+ singly-doped borate glasses or CdS-quantum dot (CdS-QD) coated lenses efficiently convert UV light to 542 nm or 613 nm wavelength narrow-band green or red light, or wide-spectrum white light, and thereby provide extra visible light to the eye. In zebrafish (wild-type larvae and adult control animals, retinal degeneration mutants, and light-induced photoreceptor cell degeneration models), the use of Tb3+ or Eu3+ doped luminescence glass or CdS-QD coated glass lenses provide additional visible light to the rod and cone photoreceptor cells, and thereby improve the visual system functions. The data provide proof-of-concept for the future development of optic devices for improvement of visual system functions in patients who suffer from photoreceptor cell degeneration or related retinal diseases. PMID:26860393

  18. Luminescence- and nanoparticle-mediated increase of light absorption by photoreceptor cells: Converting UV light to visible light.

    PubMed

    Li, Lei; Sahi, Sunil K; Peng, Mingying; Lee, Eric B; Ma, Lun; Wojtowicz, Jennifer L; Malin, John H; Chen, Wei

    2016-01-01

    We developed new optic devices - singly-doped luminescence glasses and nanoparticle-coated lenses that convert UV light to visible light - for improvement of visual system functions. Tb(3+) or Eu(3+) singly-doped borate glasses or CdS-quantum dot (CdS-QD) coated lenses efficiently convert UV light to 542 nm or 613 nm wavelength narrow-band green or red light, or wide-spectrum white light, and thereby provide extra visible light to the eye. In zebrafish (wild-type larvae and adult control animals, retinal degeneration mutants, and light-induced photoreceptor cell degeneration models), the use of Tb(3+) or Eu(3+) doped luminescence glass or CdS-QD coated glass lenses provide additional visible light to the rod and cone photoreceptor cells, and thereby improve the visual system functions. The data provide proof-of-concept for the future development of optic devices for improvement of visual system functions in patients who suffer from photoreceptor cell degeneration or related retinal diseases. PMID:26860393

  19. Method for effectively utilizing tunable one-pump fiber parametric wavelength converters as an enabling device for WDM routers.

    PubMed

    Cui, Sheng; Liu, Deming; Wang, Ying; Tu, Feng

    2009-02-01

    In this paper a method is proposed to maximize the bandwidth of the WDM router based on one-pump fiber parametric wavelength converters. It is proved that for such converters there exists an optimum signal (idler) frequency at which the output (input) tuning range can be maximized. Analytical expressions of the optimum frequency and the maximal tuning range are deduced. Then a two-stage bidirectional wavelength conversion method is proposed. With this method the bandwidth of the WDM router based on such a converter can be significantly improved compared to the one-stage ones by 252% if ordinary highly nonlinear fibers are used or 390% if fibers with optimal fourth order dispersion are used. PMID:19188974

  20. UV Pump - VUV Probe Studies of Ultrafast Dynamics in Simple Aromatic Molecules

    NASA Astrophysics Data System (ADS)

    Shivaram, Niranjan; Champenois, Elio; Cryan, James; Wright, Travis; Belkacem, Ali

    2015-05-01

    Aromatic molecules like nitro-phenols play an important role in atmospheric chemistry. They have a high absorption cross section in the ultraviolet (UV) where excitations lead to different fragmentation pathways involving internal relaxation processes. These pathways lead to elimination of the hydroxyl and nitro groups, internal re-arrangement of these groups and even formation of bonds between them. We use a high pulse energy, high repetition rate femtosecond laser system (30 mJ, 1 kHz, 780 nm, 25 fs) to generate high flux vacuum ultraviolet (VUV)/extreme ultraviolet (XUV) high order harmonics in a gas such as argon. These harmonics are then used to study femtosecond time resolved dynamics in neutral 2-Nitrophenol excited to a manifold of states around 4.75 eV and probed with higher harmonics. A velocity map imaging spectrometer is used to obtain energy/angle resolved photo-ion and photoelectron spectra as a function of pump-probe delay. Supported by Chemical Sciences, Geosciences and Biosciences division of BES/DOE.

  1. Flame Characterization Using a Tunable Solid-State Laser with Direct UV Pumping

    NASA Technical Reports Server (NTRS)

    Kamal, Mohammed M.; Dubinskii, Mark A.; Misra, Prabhakar

    1996-01-01

    Tunable solid-state lasers with direct UV pumping, based on d-f transitions of rare earth ions incorporated in wide band-gap dielectric crystals, are reliable sources of laser radiation that are suitable for excitation of combustion-related free radicals. We have employed such a laser for analytical flame characterization utilizing Laser-Induced Fluorescence (LIF) techniques. LIF spectra of alkane-air flames (used for studying combustion processes under normal and microgravity conditions) excited in the region of the A-X (0,0) OH-absorption band have been recorded and found to be both temperature-sensitive and positionally-sensitive. In addition, also clearly noticeable was the sensitivity of the spectra to the specific wavelength used for data registration. The LiCAF:Ce laser shows good prospects for being able to cover the spectral region between 280 and 340 nm and therefore be used excitation of combustion-intermediates such as the hydroxyl OH, methoxy CH30 and methylthio CH3S radicals.

  2. Time-Resolved UV-Pump (4.8eV) and Vacuum-UV (8eV) Probe Experiments of Neutral Excited State Dynamics

    NASA Astrophysics Data System (ADS)

    Horton, Spencer; Liu, Yusong; Matsika, Spiridoula; Weinacht, Thomas

    2016-05-01

    Excited state dynamics in polyatomic molecules involve a rich mixture of internal conversion, intersystem crossing, isomerization, and dissociation. Probing these dynamics with ultrafast laser pulses poses a number of challenges, in terms of both the execution of the measurements and their interpretation. We have developed an apparatus for probing excited state dynamics using a 260nm UV-pump pulse and a 156nm Vacuum-UV (VUV) probe pulse. For many systems of interest, an 8eV probe pulse can ionize the molecule from essentially any position along the excited state potential, while not having a background ionization yield from the ground state. Furthermore, given the perturbative interaction of each pulse with the molecule, it is possible interpret and model the experimental results with greater ease and confidence than more complicated probe interactions such as strong field ionization. We compare UV-IR strong-field ionization pump-probe experiments previously conducted directly with our 8eV probing and explore the differences between the two.

  3. Recent Progress Made in the Development of High-Energy UV Transmitter

    NASA Technical Reports Server (NTRS)

    Prasad, Narasimha S.; Singh, Upendra N.; Armstrong, Darrell J.

    2007-01-01

    In this paper, the status of an all-solid-state UV converter development for ozone sensing applications is discussed. A high energy Nd:YAG laser for pumping the UV converter arrangement was recently reported. The pump is an all-solid-state, single longitudinal mode, and conductively cooled Nd:YAG laser operating at 1064 nm wavelength. Currently, this pump laser provides an output pulse energy of greater than 1J/pulse at 50 Hz PRF and a pulsewidth of 22 ns with an electrical-to-optical system efficiency of greater than 7% and a M(sup 2) value of approx. 2. The spatial profile of the output beam is a rectangular super Gaussian. This Nd:YAG pump laser has been developed to pump the nonlinear optics based UV converter arrangement to generate 320 nm and 308 nm wavelengths by means of 532 nm wavelength. Previously, this UV converter arrangement has demonstrated IR-to-UV conversion efficiency of 24% using a flash lamp pumped laser providing a round, flat top spatial profile. Recently, the UV converter was assembled and tested at NASA LaRC for pumping with the diode pumped Nd:YAG laser. With current spatial profile, the UV converter was made operational. Current efforts to maximize the nonlinear conversion efficiency by refining its spatial profile to match RISTRA OPO requirements are progressing.

  4. Eu2+ and Eu3+ based "concentrated phosphors" as converters for UV LED light: two approaches and two new examples

    NASA Astrophysics Data System (ADS)

    Batentschuk, M.; Geisler, R.; Hum, J.; Iqbal, F.; Meister, F.; Osvet, A.; Stiegelschmitt, A.; Winnacker, A.

    2012-01-01

    The absolute majority of phosphors are composed of a host lattice and some percentage of an activator. At higher activator concentrations the concentration quenching occurs. However, there are phosphors in which only minor quenching of the emission occurs with increasing of the activator content. Based on the existence of two different valence states of the Eu ion (2+ and 3+), two approaches for the development of "concentrated phosphors", i.e. light emitting materials in which the activator ion is a main part of the crystal lattice, are discussed. In both approaches, reduced energy migration leading to the luminescence quenching is considered as a main condition to reach a high quantum efficiency of a concentrated phosphor. Two kinds of phosphors—Eu2+-doped alumosilicate and Eu3+-doped oxyfluoride—are used as an experimental basis for this discussion. Starting from the stoichiometric Ca_{1-x}Eux^{2+}Al2Si2O8 anorthite and Eu3+OF oxyfluorides, the non-stoichiometric powders with Eu^{2+}_{0.92}Al_{1.76}Si_{2.24}O8, Eu3+(O, F)2,35 and Eu3+(O, F)2,16 compositions were synthesized by a solid state reaction and investigated. It was shown that—in spite of the almost 100% Eu concentration—light converters with high quantum efficiency of more than 45% can be realized. A possible application of these materials as UV LED light converters for white light emitting diodes are discussed as well.

  5. iCONVERT: an integrated device for the UV-assisted determination of H2S via mid-infrared gas sensors.

    PubMed

    Petruci, João Flavio da Silveira; Cardoso, Arnaldo Alves; Wilk, Andreas; Kokoric, Vjekoslav; Mizaikoff, Boris

    2015-10-01

    In this technical note, we describe an integrated device platform for performing in-flow gaseous conversion reactions based on ultraviolet (UV) irradiation. The system combines, using the same footprint, an integrated UV-conversion device (iCONVERT), a preconcentrator unit (iPRECON), and a new generation of mid-infrared (MIR) gas cell simultaneously serving as a photon conduit, i.e., so-called substrate-integrated hollow waveguide (iHWG) optically coupled to a compact Fourier transform-infrared (FT-IR) spectrometer. The iCONVERT is assembled from two blocks of aluminum (dimensions, 75 mm × 50 mm × 40 mm; L × W × D) containing 4 miniaturized UV-lamps (47mm × 6 mm × 47 mm each). For the present study, the iPRECON-iCONVERT-iHWG sensing platform has specifically been tailored to the determination of H2S in gaseous samples. Thereby, the quantitative UV-assisted conversion of the rather weak IR-absorber H2S into the more pronouncedly responding SO2 is used for hydrogen sulfide detection. A linear calibration model was established in the range of 7.5 to 100 ppmv achieving a limit of detection at 1.5 ppmv using 10 min of sample preconcentration (onto Molecular Sieve 5A) at a flow rate of 200 mL min(-1). When compared to a conventional UV-conversion system, the iCONVERT revealed similar performance. Considering the potential for system miniaturization using, e.g., dedicated quantum cascade lasers (QCL) in lieu of the FT-IR spectrometer, the developed sensing platform may be further evolved into a hand-held device. PMID:26369573

  6. Coherent combining of fiber-laser-pumped frequency converters using all fiber electro-optic modulator for active phase control

    NASA Astrophysics Data System (ADS)

    Bourdon, P.; Durécu, A.; Canat, G.; Le Gouët, J.; Goular, D.; Lombard, L.

    2015-03-01

    Coherent beam combining (CBC) by active phase control could be useful for power scaling fiber-laser-pumped optical frequency converters like OPOs. However, a phase modulator operating at the frequency-converted wavelength is needed, which is non standard component. Fortunately, nonlinear conversion processes rely on a phase-matching condition correlating, not only the wave vectors of the coupled waves, but also their phases. This paper demonstrates that, using this phase correlation for indirect control of the phase, coherent combining of optical frequency converters is feasible using standard all-fibered electro-optic modulators. For the sake of demonstration, this new technique is experimentally applied twice for continuous wave second-harmonic-generator (SHG) combination: i) combining 2 SHG of 1.55-μm erbium-doped fiber amplifiers in PPLN crystals generating 775-nm beams; ii) combining 2 SHG of 1.064-μm ytterbium-doped fiber amplifiers in LBO crystals generating 532-nm beams. Excellent CBC efficiency is achieved on the harmonic waves in both these experiments, with λ/20 and λ/30 residual phase error respectively. In the second experiment, I/Q phase detection is added on fundamental and harmonic waves to measure their phase variations simultaneously. These measurements confirm the theoretical expectations and formulae of correlation between the phases of the fundamental and harmonic waves. Unexpectedly, in both experiments, when harmonic waves are phase-locked, a residual phase difference remains between the fundamen tal waves. Measurements of the spectrum of these residual phase differences locate them above 50 Hz, revealing that they most probably originate in fast-varying optical path differences induced by turbulence and acoustic-waves on the experimental breadboard.

  7. Photodissociation dynamics of iodocyclohexane upon UV excitation by femtosecond pump-probe technique

    NASA Astrophysics Data System (ADS)

    Hu, Chunlong; Wang, Lian; Wang, Yanmei; Tang, Ying; Long, Jinyou; Zhang, Bing

    2016-08-01

    The photodissociation dynamics of iodocyclohexane in the A-band and C-state have been investigated by femtosecond time-resolved time-of-flight mass spectroscopy. Iodocyclohexane was pumped by 266 nm pulse to its A-band. The following dissociation dynamics is prompt and direct. The time it takes for the progression of the wave packet from the dissociative state to the dissociating asymptotic region is around 180 fs. The C-state was excited by 200 nm pump pulse and it has predissociative character with predissociation time of about 600 fs, which may have contributions from multiple vibrational modes.

  8. UV-VIS-NIR luminescence properties of an intense 5d broadband sensitized Eu2SiS4:Er3+ suitable for solar spectral converter

    NASA Astrophysics Data System (ADS)

    Zhang, Gongguo; Cui, Qiuyu; Liu, Guodong

    2016-07-01

    A novel broadband sensitized near-infrared emitting phosphor, Eu2SiS4:Er3+, was developed as promising solar spectral converter for Si solar cells. Eu2SiS4:Er3+ has broadband absorptions ranging from 250 nm to 550 nm which can efficiently facilitate the UV-green part of the solar photon flux spectrum and exhibits intense NIR emission of Er3+, perfectly matching the maximum spectral response of Si solar cells. The NIR integrated emission intensity of Eu2SiS4:0.02Er3+ is 6.14 times as intense as that of a dual-mode solar spectral converter CaLaGa3S6O:0.01Ce3+, 0.06Pr3+. These results demonstrate that Eu2SiS4:Er3+ phosphor is a promising candidate used as solar spectral converter.

  9. Light-emitting Ga-oxide nanocrystals in glass: a new paradigm for low-cost and robust UV-to-visible solar-blind converters and UV emitters

    NASA Astrophysics Data System (ADS)

    Sigaev, Vladimir N.; Golubev, Nikita V.; Ignat'eva, Elena S.; Paleari, Alberto; Lorenzi, Roberto

    2014-01-01

    Wide-bandgap nanocrystals are an inexhaustible source of tuneable functions potentially addressing most of the demand for new light emitting systems. However, the implementation of nanocrystal properties in real devices is not straightforward if a robust and stable optical component is required as a final result. The achievement of efficient light emission from dense dispersions of Ga-oxide nanocrystals in UV-grade glass can be a breakthrough in this regard. Such a result would permit the fabrication of low cost UV-to-visible converters for monitoring UV-emitting events on a large-scale - from invisible hydrogen flames to corona dispersions. From this perspective, γ-Ga2O3 nanocrystals are developed by phase separation in Ga-alkali-germanosilicate glasses, obtaining optical materials based on a UV transparent matrix. Band-to-band UV-excitation of light emission from donor-acceptor pair (DAP) recombination is investigated for the first time in embedded γ-Ga2O3. The analysis of the decay kinetics gives unprecedented evidence that nanosized confinement of DAP recombination can force a nanophase to the efficient response of exactly balanced DAPs. The results, including a proof of concept of UV-to-visible viewer, definitely demonstrate the feasibility of workable glass-based fully inorganic nanostructured materials with emission properties borrowed from Ga2O3 single-crystals and tailored by the nanocrystal size.Wide-bandgap nanocrystals are an inexhaustible source of tuneable functions potentially addressing most of the demand for new light emitting systems. However, the implementation of nanocrystal properties in real devices is not straightforward if a robust and stable optical component is required as a final result. The achievement of efficient light emission from dense dispersions of Ga-oxide nanocrystals in UV-grade glass can be a breakthrough in this regard. Such a result would permit the fabrication of low cost UV-to-visible converters for monitoring UV

  10. UV-Sensitivity of Shiga Toxin-Converting Bacteriophage Virions Φ24B, 933W, P22, P27 and P32.

    PubMed

    Bloch, Sylwia; Nejman-Faleńczyk, Bożena; Topka, Gracja; Dydecka, Aleksandra; Licznerska, Katarzyna; Narajczyk, Magdalena; Necel, Agnieszka; Węgrzyn, Alicja; Węgrzyn, Grzegorz

    2015-09-01

    Shiga toxin-converting bacteriophages (Stx phages) are present as prophages in Shiga toxin-producing Escherichia coli (STEC) strains. Theses phages can be transmitted to previously non-pathogenic E. coli cells making them potential producers of Shiga toxins, as they bear genes for these toxins in their genomes. Therefore, sensitivity of Stx phage virions to various conditions is important in both natural processes of spreading of these viruses and potential prophylactic control of appearance of novel pathogenic E. coli strains. In this report we provide evidence that virions of Stx phages are significantly more sensitive to UV irradiation than bacteriophage λ. Following UV irradiation of Stx virions at the dose of 50 J/m², their infectivity dropped by 1-3 log10, depending on the kind of phage. Under these conditions, a considerable release of phage DNA from virions was observed, and electron microscopy analyses indicated a large proportion of partially damaged virions. Infection of E. coli cells with UV-irradiated Stx phages resulted in significantly decreased levels of expression of N and cro genes, crucial for lytic development. We conclude that inactivation of Stx virions caused by relatively low dose of UV light is due to damage of capsids that prevents effective infection of the host cells. PMID:26402701

  11. UV-Sensitivity of Shiga Toxin-Converting Bacteriophage Virions Φ24B, 933W, P22, P27 and P32

    PubMed Central

    Bloch, Sylwia; Nejman-Faleńczyk, Bożena; Topka, Gracja; Dydecka, Aleksandra; Licznerska, Katarzyna; Narajczyk, Magdalena; Necel, Agnieszka; Węgrzyn, Alicja; Węgrzyn, Grzegorz

    2015-01-01

    Shiga toxin-converting bacteriophages (Stx phages) are present as prophages in Shiga toxin-producing Escherichia coli (STEC) strains. Theses phages can be transmitted to previously non-pathogenic E. coli cells making them potential producers of Shiga toxins, as they bear genes for these toxins in their genomes. Therefore, sensitivity of Stx phage virions to various conditions is important in both natural processes of spreading of these viruses and potential prophylactic control of appearance of novel pathogenic E. coli strains. In this report we provide evidence that virions of Stx phages are significantly more sensitive to UV irradiation than bacteriophage λ. Following UV irradiation of Stx virions at the dose of 50 J/m2, their infectivity dropped by 1–3 log10, depending on the kind of phage. Under these conditions, a considerable release of phage DNA from virions was observed, and electron microscopy analyses indicated a large proportion of partially damaged virions. Infection of E. coli cells with UV-irradiated Stx phages resulted in significantly decreased levels of expression of N and cro genes, crucial for lytic development. We conclude that inactivation of Stx virions caused by relatively low dose of UV light is due to damage of capsids that prevents effective infection of the host cells. PMID:26402701

  12. UV-VUV excimer emitter pumped by a subnormal glow discharge

    SciTech Connect

    Shuaibov, Aleksandr K; Dashchenko, Arkadii I; Shevera, Igor' V

    2001-04-30

    Characteristics of a small-size excimer emitter operating on an Ar - Cl{sub 2} mixture excited by a subnormal glow discharge are studied. It is shown that this discharge is a source of multiwavelength emission in a range of 175 - 258 nm. The optimum pressures lie in ranges of 0.3 - 0.5 kPa for chlorine and 2 - 4 kPa for argon. The average power of UV- VUV emission reaches 0.7 W, with the emission efficiency equal to 3 %. The emitter can be used in microelectronics, high-energy chemistry, short-wavelength photometry, biophysics, and medicine. (laser applications and other topics in quantum electronics)

  13. PUMPS

    DOEpatents

    Thornton, J.D.

    1959-03-24

    A pump is described for conveving liquids, particure it is not advisable he apparatus. The to be submerged in the liquid to be pumped, a conduit extending from the high-velocity nozzle of the injector,and means for applying a pulsating prcesure to the surface of the liquid in the conduit, whereby the surface oscillates between positions in the conduit. During the positive half- cycle of an applied pulse liquid is forced through the high velocity nozzle or jet of the injector and operates in the manner of the well known water injector and pumps liquid from the main intake to the outlet of the injector. During the negative half-cycle of the pulse liquid flows in reverse through the jet but no reverse pumping action takes place.

  14. Measurement of submilliwatt, picosecond terahertz emission from a femtosecond-laser-pumped solid-state dc to ac radiation converter based on a ZnSe crystal

    SciTech Connect

    Yugami, Noboru; Ohata, Nobuo; Yaegashi, Kenta; Kawanago, Hiroshi

    2006-11-15

    We measured the terahertz pulse emission from a femtosecond-laser-pumped solid-state dc to ac radiation converter using a 150 fs Ti:sapphire laser pulse for dense plasma diagnostics. The laser-produced ionization front was directly modulated from a periodic electrostatic field to pulsed emission. The central frequency of the emission was measured to be 0.13 THz having a bandwidth of 0.1 THz and a peak power of 0.2 mW. This emission source is suitable for use in various novel diagnostic techniques, such as dense plasma diagnostics.

  15. Optically pumped quantum-dot Cd(Zn)Se/ZnSe laser and microchip converter for yellow—green spectral region

    NASA Astrophysics Data System (ADS)

    Lutsenko, E. V.; Voinilovich, A. G.; Rzheutskii, N. V.; Pavlovskii, V. N.; Yablonskii, G. P.; Sorokin, S. V.; Gronin, S. V.; Sedova, I. V.; Kop'ev, Petr S.; Ivanov, Sergei V.; Alanzi, M.; Hamidalddin, A.; Alyamani, A.

    2013-05-01

    The room temperature laser generation in the yellow—green (λ = 558.5-566.7 nm) spectral range has been demonstrated under optical pumping by a pulsed nitrogen laser of Cd(Zn)Se/ZnSe quantum dot heterostructures. The maximum achieved laser wavelength was as high as λ = 566.7 nm at a laser cavity length of 945 μm. High values of both the output pulsed power (up to 50 W) and the external differential quantum efficiency (~60%) were obtained at a cavity length of 435 μm. Both a high quality of the laser heterostructure and a low lasing threshold (~2 kW cm-2) make it possible to use a pulsed InGaN laser diode as a pump source. A laser microchip converter based on this heterostructure has demonstrated a maximum output pulse power of ~90 mW at λ = 560 nm. The microchip converter was placed in a standard TO-18 (5.6 mm in diameter) laser diode package.

  16. Optically pumped quantum-dot Cd(Zn)Se/ZnSe laser and microchip converter for yellow-green spectral region

    SciTech Connect

    Lutsenko, E V; Voinilovich, A G; Rzheutskii, N V; Pavlovskii, V N; Yablonskii, G P; Sorokin, S V; Gronin, S V; Sedova, I V; Kop'ev, Petr S; Ivanov, Sergei V; Alanzi, M; Hamidalddin, A; Alyamani, A

    2013-05-31

    The room temperature laser generation in the yellow-green ({lambda} = 558.5-566.7 nm) spectral range has been demonstrated under optical pumping by a pulsed nitrogen laser of Cd(Zn)Se/ZnSe quantum dot heterostructures. The maximum achieved laser wavelength was as high as {lambda} = 566.7 nm at a laser cavity length of 945 {mu}m. High values of both the output pulsed power (up to 50 W) and the external differential quantum efficiency ({approx}60%) were obtained at a cavity length of 435 {mu}m. Both a high quality of the laser heterostructure and a low lasing threshold ({approx}2 kW cm{sup -2}) make it possible to use a pulsed InGaN laser diode as a pump source. A laser microchip converter based on this heterostructure has demonstrated a maximum output pulse power of {approx}90 mW at {lambda} = 560 nm. The microchip converter was placed in a standard TO-18 (5.6 mm in diameter) laser diode package. (semiconductor lasers. physics and technology)

  17. 46 CFR 32.52-5 - Bilge piping for pump rooms and adjacent cofferdams on tank vessels constructed or converted on...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... provided for controlling the cargo or pump room bilge pumps and their suctions or discharges in order that a flooded pump room may be pumped out. Suitable portable or manually operated pumps may be accepted... are operable from inside the pump room and either from an accessible position outside the pump...

  18. Sub-20-fs pulses tunable across the visible from a blue-pumped single-pass noncollinear parametric converter.

    PubMed

    Wilhelm, T; Piel, J; Riedle, E

    1997-10-01

    Femtosecond pulses with center wavelengths between 470 and 750 nm are generated in a single-stage type I BBO optical parametric amplifier pumped by a frequency-doubled 1-kHz Ti:sapphire amplifier. A high-quality white-light continuum is used as the seed. Pulse durations as short as 16 fs and pulse energies of as much as 11 microJ are observed. The quantum efficiency is ~25% for both 7- and 40-microJ pump pulses. This unique combination of ultrashort pulse duration and high conversion is made possible by noncollinear phase matching that permits a sufficiently large amplification bandwidth. Simultaneously the group velocities of the signal and the idler are effectively matched. As a result widely tunable sub-20-fs pulses can be generated in a nonlinear crystal as thick as 2 mm. PMID:18188279

  19. Simulations of a FIR Oscillator with Large Slippage parameter at Jefferson Lab for FIR/UV pump-probe experiments

    SciTech Connect

    Benson, Stephen V.; Campbell, L. T.; McNeil, B.W.T.; Neil, George R.; Shinn, Michelle D.; Williams, Gwyn P.

    2014-03-01

    We previously proposed a dual FEL configuration on the UV Demo FEL at Jefferson Lab that would allow simultaneous lasing at FIR and UV wavelengths. The FIR source would be an FEL oscillator with a short wiggler providing diffraction-limited pulses with pulse energy exceeding 50 microJoules, using the exhaust beam from a UVFEL as the input electron beam. Since the UV FEL requires very short pulses, the input to the FIR FEL is extremely short compared to a slippage length and the usual Slowly Varying Envelope Approximation (SVEA) does not apply. We use a non-SVEA code to simulate this system both with a small energy spread (UV laser off) and with large energy spread (UV laser on).

  20. 46 CFR 32.52-5 - Bilge piping for pump rooms and adjacent cofferdams on tank vessels constructed or converted on...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... from a cargo pump or cargo stripping pump may be provided for this purpose. The bilge pump shall not be... are normally present. (b) Where a bilge suction is provided from a cargo or stripping pump,...

  1. High Energy, Single-Mode, All-Solid-State and Tunable UV Laser Transmitter

    NASA Technical Reports Server (NTRS)

    Prasad, Narasimha S.; Singh, Upendra N.; Hovis, FLoyd

    2007-01-01

    A high energy, single mode, all solid-state Nd:YAG laser primarily for pumping an UV converter is developed. Greater than 1 J/pulse at 50 HZ PRF and pulse widths around 22 ns have been demonstrated. Higher energy, greater efficiency may be possible. Refinements are known and practical to implement. Technology Demonstration of a highly efficient, high-pulse-energy, single mode UV wavelength generation using flash lamp pumped laser has been achieved. Greater than 90% pump depletion is observed. 190 mJ extra-cavity SFG; IR to UV efficiency > 21% (> 27% for 1 mJ seed). 160 mJ intra-cavity SFG; IR to UV efficiency up to 24% Fluence < 1 J/sq cm for most beams. The pump beam quality of the Nd:YAG pump laser is being refined to match or exceed the above UV converter results. Currently the Nd:YAG pump laser development is a technology demonstration. System can be engineered for compact packaging.

  2. Development and Implementation of an Ultrafast Vacuum-UV (8eV) Light Source for use in UV-VUV Pump Probe Experiments of Neutral Excited State Dynamics

    NASA Astrophysics Data System (ADS)

    Liu, Yusong; Horton, Spencer; Matsika, Spiridoula; Weinacht, Thomas

    2016-05-01

    Probing neutral excited state dynamics in polyatomic molecules with ultrafast laser systems enables us to study phenomena such as internal conversion, isomerization, intersystem crossing, and dissociation. Using the third harmonic (260 nm) and the fifth harmonic (156 nm) of our laser system we have developed an apparatus to perform pump-probe experiments for the study neutral excited state dynamics in various polyatomic molecules. The fifth harmonic of our laser system is generated through the four-wave-mixing process of k5 ω = 2k3 ω -kω performed with a non-collinear geometry in an argon gas cell. In several polyatomic molecular systems of interest a photon with 8 eV of energy gives us the unique ability to ionize from essentially anywhere along the excited state potential, but does not produce any ionization yield from the ground state. This enables us to measure excited state lifetimes without the photon energy becoming too low to ionize while the nuclear wave-packet is traveling on the excited state potential. We also have the advantage of working in the perturbative weak-field ionization regime. These experiments can also be directly compare to strong-field ionization experiments conducted with a UV-pump and an IR-probe conducted on the same molecules.

  3. Short pulse width UV laser at 355 nm based on pulse LD side-pumped ceramic Nd:YAG and BBO electro-optical Q-switched

    NASA Astrophysics Data System (ADS)

    Bai, Y.; Chen, X. M.; Lu, B. L.; Ren, Z. Y.; Bai, J. T.

    2012-02-01

    355 nm UV laser was obtained with a pulse width of less than 5 ns and a peak power at megawatt level by adopting the 808 nm pulse laser diode (LD) side-pumped ceramic Nd:YAG and BBO crystal electrooptical Q-switched. The single-pulse energy was measured to be 24.3 mJ with 4.86 ns pulse width and 5.11 MW peak power at a repetition rate of 1Hz under a 120 A pump current. Using a volume of beam splitting mirrors, wavelength outputs at 1064, 532, and 355 nm pulse laser was obtained simultaneously with a respective average output power of 656.6, 357.1, and 260.5 mW, the beam quality factor M 2 are ( M {/x - 1064 2} = 5.83, M {/y - 1064 2} = 5.61), ( M {/x - 532 2} = 4.25, M {/y - 532 2} = 4.08) and ( M {/x - 355 2} = 6.32, M {/y - 355 2} = 6.15), corresponding to a conversion efficiency at 11% from 1064 to 355 nm.

  4. Picosecond Time-Resolved Ir-Uv Pump-Probe Spectroscopic Study on Vibrational Energy Relaxation of Benzene Dimer and Trimer in the CH Stretching Region

    NASA Astrophysics Data System (ADS)

    Kusaka, Ryoji; Inokuchi, Yoshiya; Ebata, Takayuki

    2012-06-01

    Vibrational energy relaxation (VER) in the CH stretching region of benzene dimer (Bz_2) and trimer (Bz_3) has been studied by IR-UV pump-probe spectroscopy in supersonic beams. Firstly, we investigated isotope-substituted hd heterodimer, where h=C_6H_6 and d=_6D_6, because the Stem and Top sites in the hd dimer can be site-selectively excited, different from hh homodimer. The two h(stem)d(top) and h(top)d(stem) isomers show remarkable difference in the lifetimes of intracluster vibrational energy redistribution (IVR). In the transient UV spectra, we observed a broad electronic transition due to the bath modes. The time evolutions of the bath modes can be described by a three step VER model involving IVR and vibrational predissociation (VP). This model was also confirmed by the observed rise profile of the Bz fragment. Secondly, we investigated hh homodimer. The hh homodimer shows the stepwise VER process with time constants similar to those of the hd dimer, suggesting a very weak excitation-exchange coupling of the vibrations between the two sites of the hh dimer. Finally, we found that Bz_3 also exhibits the stepwise VER process, though each step is faster than Bz_2.

  5. ZnCr2S4: Highly effective photocatalyst converting nitrate into N2 without over-reduction under both UV and pure visible light

    NASA Astrophysics Data System (ADS)

    Yue, Mufei; Wang, Rong; Cheng, Nana; Cong, Rihong; Gao, Wenliang; Yang, Tao

    2016-08-01

    We propose several superiorities of applying some particular metal sulfides to the photocatalytic nitrate reduction in aqueous solution, including the high density of photogenerated excitons, high N2 selectivity (without over-reduction to ammonia). Indeed, ZnCr2S4 behaved as a highly efficient photocatalyst, and with the assistance of 1 wt% cocatalysts (RuOx, Ag, Au, Pd, or Pt), the efficiency was greatly improved. The simultaneous loading of Pt and Pd led to a synergistic effect. It offered the highest nitrate conversion rate of ~45 mg N/h together with the N2 selectivity of ~89%. Such a high activity remained steady after 5 cycles. The optimal apparent quantum yield at 380 nm was 15.46%. More importantly, with the assistance of the surface plasma resonance effect of Au, the visible light activity achieved 1.352 mg N/h under full arc Xe-lamp, and 0.452 mg N/h under pure visible light (λ > 400 nm). Comparing to the previous achievements in photocatalytic nitrate removal, our work on ZnCr2S4 eliminates the over-reduction problem, and possesses an extremely high and steady activity under UV-light, as well as a decent conversion rate under pure visible light.

  6. ZnCr2S4: Highly effective photocatalyst converting nitrate into N2 without over-reduction under both UV and pure visible light

    PubMed Central

    Yue, Mufei; Wang, Rong; Cheng, Nana; Cong, Rihong; Gao, Wenliang; Yang, Tao

    2016-01-01

    We propose several superiorities of applying some particular metal sulfides to the photocatalytic nitrate reduction in aqueous solution, including the high density of photogenerated excitons, high N2 selectivity (without over-reduction to ammonia). Indeed, ZnCr2S4 behaved as a highly efficient photocatalyst, and with the assistance of 1 wt% cocatalysts (RuOx, Ag, Au, Pd, or Pt), the efficiency was greatly improved. The simultaneous loading of Pt and Pd led to a synergistic effect. It offered the highest nitrate conversion rate of ~45 mg N/h together with the N2 selectivity of ~89%. Such a high activity remained steady after 5 cycles. The optimal apparent quantum yield at 380 nm was 15.46%. More importantly, with the assistance of the surface plasma resonance effect of Au, the visible light activity achieved 1.352 mg N/h under full arc Xe-lamp, and 0.452 mg N/h under pure visible light (λ > 400 nm). Comparing to the previous achievements in photocatalytic nitrate removal, our work on ZnCr2S4 eliminates the over-reduction problem, and possesses an extremely high and steady activity under UV-light, as well as a decent conversion rate under pure visible light. PMID:27484161

  7. ZnCr2S4: Highly effective photocatalyst converting nitrate into N2 without over-reduction under both UV and pure visible light.

    PubMed

    Yue, Mufei; Wang, Rong; Cheng, Nana; Cong, Rihong; Gao, Wenliang; Yang, Tao

    2016-01-01

    We propose several superiorities of applying some particular metal sulfides to the photocatalytic nitrate reduction in aqueous solution, including the high density of photogenerated excitons, high N2 selectivity (without over-reduction to ammonia). Indeed, ZnCr2S4 behaved as a highly efficient photocatalyst, and with the assistance of 1 wt% cocatalysts (RuOx, Ag, Au, Pd, or Pt), the efficiency was greatly improved. The simultaneous loading of Pt and Pd led to a synergistic effect. It offered the highest nitrate conversion rate of ~45 mg N/h together with the N2 selectivity of ~89%. Such a high activity remained steady after 5 cycles. The optimal apparent quantum yield at 380 nm was 15.46%. More importantly, with the assistance of the surface plasma resonance effect of Au, the visible light activity achieved 1.352 mg N/h under full arc Xe-lamp, and 0.452 mg N/h under pure visible light (λ > 400 nm). Comparing to the previous achievements in photocatalytic nitrate removal, our work on ZnCr2S4 eliminates the over-reduction problem, and possesses an extremely high and steady activity under UV-light, as well as a decent conversion rate under pure visible light. PMID:27484161

  8. Alternative backing up pump for turbomolecular pumps

    DOEpatents

    Myneni, Ganapati Rao

    2003-04-22

    As an alternative to the use of a mechanical backing pump in the application of wide range turbomolecular pumps in ultra-high and extra high vacuum applications, palladium oxide is used to convert hydrogen present in the evacuation stream and related volumes to water with the water then being cryo-pumped to a low pressure of below about 1.e.sup.-3 Torr at 150.degree. K. Cryo-pumping is achieved using a low cost Kleemenco cycle cryocooler, a somewhat more expensive thermoelectric cooler, a Venturi cooler or a similar device to achieve the required minimization of hydrogen partial pressure.

  9. Mechanical drive for blood pump

    DOEpatents

    Bifano, N.J.; Pouchot, W.D.

    1975-07-29

    This patent relates to a highly efficient blood pump to be used as a replacement for a ventricle of the human heart to restore people disabled by heart disease. The mechanical drive of the present invention is designed to operate in conjunction with a thermoelectric converter power source. The mechanical drive system essentially converts the output of a rotary power into pulsatile motion so that the power demand from the thermoelectric converter remains essentially constant while the blood pump output is pulsed. (auth)

  10. Abnormal anti-quenching and controllable multi-transitions of Bi3+ luminescence by temperature in a yellow-emitting LuVO4 :Bi3+ phosphor for UV-converted white LEDs.

    PubMed

    Kang, Fengwen; Peng, Mingying; Zhang, Qinyuan; Qiu, Jianrong

    2014-09-01

    Phosphors with an efficient yellow-emitting color play a crucial role in phosphor-converted white LEDs (pc-WLEDs), but popular yellow phosphors such as YAG:Ce or Eu(2+) -doped (oxy)nitrides cannot smoothly meet this seemingly simple requirement due to their strong absorptions in the visible range. Herein, we report a novel yellow-emitting LuVO(4) :Bi(3+) phosphor that can solve this shortcoming. The emission from LuVO(4) :Bi(3+) shows a peak at 576 nm with a quantum efficiency (QE) of up to 68 %, good resistance to thermal quenching (T(50 %) =573 K), and no severe thermal degradation after heating-cooling cycles upon UV excitation. The yellow emission, as verified by X-ray photoelectron spectra (XPS), originates from the ((3)P(0),(3)P(1))→(1) S0 transitions of Bi(3+). Increasing the temperature from 10 to 300 K produces a temperature-dependent energy-transfer process between VO(4)(3-) groups and Bi(3+), and further heating of the samples to 573 K intensifies the emission. However, it subsequently weakens, accompanied by blueshifts of the emission peaks. This abnormal anti-thermal quenching can be ascribed to temperature-dependent energy transfer from VO(4)(3-) groups to Bi(3+), a population redistribution between the excited states of (3)P(0) and (3)P(1) upon thermal stimulation, and discharge of electrons trapped in defects with a trap depth of 359 K. Device fabrication with the as-prepared phosphor LuVO(4) :Bi(3+) has proved that it can act as a good yellow phosphor for pc-WLEDs. PMID:25048156

  11. Fast gradient high performance liquid chromatography method with UV detection for simultaneous determination of seven angiotensin converting enzyme inhibitors together with hydrochlorothiazide in pharmaceutical dosage forms and spiked human plasma and urine.

    PubMed

    Elsebaei, Fawzi; Zhu, Yan

    2011-07-15

    The development of a reversed phase liquid chromatographic method for the simultaneous determination of seven angiotensin converting enzyme (ACE) inhibitors; five drugs namely benazepril HCl (BZL), enalapril maleate (ENL), fosinopril sodium (FSP), lisinopril (LSP) and ramipril (RMP) and two metabolites captopril disulfide (CPD) and enalaprilat (ENT) together with hydrochlorothiazide (HCT) is described. The method can serve as a substitute for many published papers for the analysis of the targeted compounds with or without hydrochloothiazide in pharmaceutical formulations as well as in spiked human plasma and urine samples. The method utilizes a simple gradient procedure for the separation in a 11 min run time using acetonitrile aqueous ammonia buffer (pH 9) solution and an Extend RP-C18 (25 μm particle size, 4.6 mm×250 mm, Agilent) HPLC column. The effluent was monitored on a UV detector at 215 nm. The effect of pH, solvent strength and analysis time on the peak shape and quantification were carefully studied in order to optimize the method. Adopting the proposed procedure, the analytes produce well-shaped peaks with good linear relationship over the investigated concentration ranges. The limits of detection (LOD) and limits of quantification (LOQ) from standard drug solutions lie in the range of 17-64 and 56-212 ng mL(-1), respectively. Correlation coefficient values (r) higher than 0.997 were obtained for all the studied drugs in spiked human plasma and urine samples. The intra-day and inter-day precision of the method was evaluated with relative standard deviation values being satisfactory for their purposed analysis. The method was validated with respect to specificity, recovery, accuracy, precision and linearity. PMID:21645680

  12. XTL Converter

    Energy Science and Technology Software Center (ESTSC)

    2015-10-07

    "XTL Converter" is a short Python script for electron microscopy simulation. The program takes an input crystal file in the VESTA *.XTL format and converts it to a text format readable by the multislice simulation program ìSTEM. The process of converting a crystal *.XTL file to the format used by the ìSTEM simulation program is quite tedious; it generally requires the user to select dozens or hundreds of atoms, rearranging and reformatting their position. Headermore » information must also be reformatted to a specific style to be read by ìSTEM. "XTL Converter" simplifies this process, saving the user time and allowing for easy batch processing of crystals.« less

  13. XTL Converter

    SciTech Connect

    Spurgeon, Steven R

    2015-10-07

    "XTL Converter" is a short Python script for electron microscopy simulation. The program takes an input crystal file in the VESTA *.XTL format and converts it to a text format readable by the multislice simulation program ìSTEM. The process of converting a crystal *.XTL file to the format used by the ìSTEM simulation program is quite tedious; it generally requires the user to select dozens or hundreds of atoms, rearranging and reformatting their position. Header information must also be reformatted to a specific style to be read by ìSTEM. "XTL Converter" simplifies this process, saving the user time and allowing for easy batch processing of crystals.

  14. Optical parametric oscillator of mid-IR, visible and UV ranges with synchronous pumping by a Q-switched mode-locked Nd : YAG laser

    NASA Astrophysics Data System (ADS)

    Donin, V. I.; Yakovin, M. D.; Yakovin, D. V.

    2016-07-01

    The parametric generation in a nonlinear PPLN crystal synchronously pumped by a Q-switched mode-locked Nd : YAG laser with a pulse duration of 45 ps is studied. The output pump intensity in the nonlinear crystal reaches ~10 GW cm-2. At a pulse repetition rate of 1 kHz, the average output power at the idler wavelength (~3.6 μm) is ~12 mW, the peak power is ~25 kW, and the conversion efficiency (with respect to the absorbed power) is ~10%. The radiation linewidth at the signal wavelength (~1.5 μm) is 13 cm-1. Along with the signal and idler waves, the output emission spectrum contains lines at wavelengths of 822, 754, 624, 532, 463, 442, 392 and 355 nm. The tunable radiation with wavelengths in the vicinity of 392, 463 and 822 nm is observed for the first time. The tuning ranges for the new lines are measured (5 – 10 nm) and their origin is explained.

  15. Magnetorheological converters

    SciTech Connect

    Zal'tsgendler, E.A.; Kolomentsev, A.V.; Kordonskii, V.I.; Madorskii, L.S.

    1986-04-01

    The authors study the problems of constructing an electrohydraulic converter functioning based on the magnetoheological effect: the magnetorheological throttle (MR throttle). Requirements are listed that must be taken into account in developing the MR throttle. The paper attempts to calculate the flow-rate characteristics of the MR throttle. The rheological equation which describes sufficiently the mechanical properties of the magnetoheological suspensions is presented. The paper examines the calculation of the magnetic inductor for the example of a toroidal core with a gap, which simultaneously functions as the slot throttling channel. The use of the designs described enabled the development of bridge converters, which have a flat amplitude-frequency characteristic in the range 200-250 Hz and which have good energy indicators. Typical experimental logarithmic amplitude-frequency and phase-frequency characteristics of a bridge converter are shown.

  16. Parametric energy converter

    SciTech Connect

    Johnson, R.N.

    1981-10-20

    A method and apparatus for converting thermal energy into mechanical energy by parametric pumping of rotary inertia. In a preferred embodiment, a modified tesla turbine rotor is positioned within a rotary boiler along its axis of rotation. An external heat source, such as solar radiation, is directed onto the outer casing of the boiler to convert the liquid to steam. As the steam spirals inwardly toward the discs of the rotor, the moment of inertia of the mass of steam is reduced to thereby substantially increase its kinetic energy. The laminar flow of steam between the discs of the rotor transfers the increased kinetic energy to the rotor which can be coupled out through an output shaft to perform mechanical work. A portion of the mechanical output can be fed back to maintain rotation of the boiler.

  17. Synthesis and photoluminescence properties of near-UV pumped yellow-emitting Li3Ba2La3(WO4)8:Dy3+ phosphors

    NASA Astrophysics Data System (ADS)

    Wang, G. Q.; Gong, X. H.; Chen, Y. J.; Huang, J. H.; Lin, Y. F.; Luo, Z. D.; Huang, Y. D.

    2014-05-01

    Li3Ba2La3(WO4)8:Dy3+ yellow-emitting phosphors were synthesized by the solid state reaction method. These phosphors exhibit one intense emission band around 575 nm under excitation at 365 nm. The dependences of the emission intensities and the chromaticity coordinates on Dy3+ concentration were analyzed. The optimum doping concentration of Dy3+ for the phosphor is about 6 mol% and the corresponding chromaticity coordinates is (0.435, 0.476) at room temperature. Besides, the Li3Ba2La3(WO4)8:Dy3+ phosphor shows higher thermal stability than that of (Sr, Ba)2SiO4:Eu2+. The results show that the Li3Ba2La3(WO4)8:Dy3+ phosphor with strong yellow emission may be applied in near ultraviolet pumped white LEDs.

  18. Stabilization of He2(A(sup 3)Sigma(sub u)(+)) molecules in liquid helium by optical pumping for vacuum UV laser

    NASA Technical Reports Server (NTRS)

    Zmuidzinas, J. S. (Inventor)

    1978-01-01

    A technique is disclosed for achieving large populations of metastable spin-aligned He2(a 3 Sigma u +) molecules in superfluid helium to obtain lasing in the vacuum ultraviolet wavelength regime around 0.0800 micron m by electronically exciting liquid (superfluid) helium with a comparatively low-current electron beam and spin aligning the metastable molecules by means of optical pumping with a modestly-powered (100mW) circularly-polarized continuous wave laser operating at, for example, 0.9096 or 0.4650 micron m. Once a high concentration of spin-aligned He2 (a 3 Sigma u +) is achieved with lifetimes of a few milliseconds, a strong microwave signal destroys the spin alignment and induces a quick collisional transition of He2 (a 3 Sigma u +) molecules to the a 1 Sigma u + state and thereby a lasing transition to the X 1 Sigma g + state.

  19. Exploring photochemistry of p-bromophenylsulfonyl, p-tolylsulfonyl and methylsulfonyl azides by ultrafast UV-pump-IR-probe spectroscopy and computations.

    PubMed

    Kuzmin, A V; Neumann, C; van Wilderen, L J G W; Shainyan, B A; Bredenbeck, J

    2016-03-28

    The photochemistry of p-bromophenylsulfonyl azide (BsN3), p-tolylsulfonyl azide (TsN3) and methylsulfonyl azide (MsN3) was studied by femtosecond time-resolved infrared spectroscopy with CH2Cl2 and CCl4 as solvents along with quantum chemical calculations. The photolysis of these azides after 267 nm light excitation leads to the population of each respective azide S1 excited state. Decay of the S1 excited state gives rise to singlet nitrene formation. In the case of BsN3, the decay was found to correlate with the formation of a pseudo-Curtius photoproduct (PCP) BrC6H4NSO2. Transient electronic ground states of the three azides on their way to singlet nitrenes and PCPs were shown by locating the corresponding transition states on the potential energy surfaces. The lifetime of singlet (1)(BsN) and (1)(TsN) nitrenes is τ(S) = ∼20 ps in CH2Cl2 and ∼700 ps in CCl4. Singlet (1)(MsN) was not detected. Due to fast intersystem crossing (ISC), singlet nitrenes are converted into the triplet spin isomers lying lower in energy, the formation time constants being equal to the corresponding singlet nitrene lifetime. The formation of (3)(MsN) was shown and the formation time constant in CH2Cl2 was found to be τ(ISC) = 34 ± 3 ps. Internal conversion of the S1 excited state to the ground state of the azide was low (Φ ≈ 0.15) for BsN3 and TsN3 and was not found in the case of MsN3. PMID:26948995

  20. Narrow linewidth UV laser transmitter for ozone DIAL remote sensing application

    NASA Astrophysics Data System (ADS)

    Chuang, Ti; Hansell, Joe; Shuman, Tim; Schum, Tom; Puffenberger, Kent; Burnham, Ralph

    2016-03-01

    Fibertek has demonstrated a dual-wavelength narrow linewidth UV laser transmitter for NASA airborne ozone DIAL remote sensing application. The application requires two narrow linewidth lasers in the UV region between 300 nm and 320 nm with at least 12 nm separation between the two wavelengths. Each UV laser was based on a novel ring structure incorporating an optical parametric oscillator (OPO) and a sum frequency generator (SFG). The fundamental pump source of the UV laser was a single frequency 532 nm laser, which was frequency-doubled from a diode-pumped, injection-seeded single frequency Nd:YAG laser operating at 1064 nm and 50 Hz repetition rate. The ring frequency converters generated UV wavelengths at 304 nm and 316 nm respectively. The demonstrated output energies were 2.6 mJ for 304 nm and 2.3 mJ for 316 nm UV lines, with room to potentially achieve more energy for each laser. Linewidth narrowing was achieved using a volume Bragg grating as the output coupler of the OPO in each ring oscillator. We obtained spectral linewidths (FWHM) of 0.12 nm for the 304 nm line and 0.1 nm for the 316 nm line, and the UV energy conversion efficiencies of 12.2% and 9.1%. Fibertek built an airborne DIAL transmitter based on the reported demonstration, which was a single optical module with dual-wavelength output at the demonstrated wavelengths. NASA plans to field the UV laser transmitter as a key component of the High Spectral Resolution Lidar-II (HSRL-II) high altitude airborne instrument to perform autonomous global ozone DIAL remote sensing field campaigns.

  1. Deuteration Effect Study on the Vibrational Dynamics of Phenol and Phenol-Water Complex by Picosecond Time-Resolved Ir-Uv Pump-Probe Spectroscopy in a Supersonic Molecular Beam

    NASA Astrophysics Data System (ADS)

    Miyazaki, Yasunori; Inokuchi, Yoshiya; Ebata, Takayuki

    2012-06-01

    The vibrational energy relaxations of the OH and OD stretch of phenol-d_0 and phenol-d_0-(H_2O) complex and phenol-d_1 and phenol-d_1-(D_2O) complex, respectively, are investigated by picosecond IR-UV pump-probe spectroscopy. The key to understand their dynamic is well-suited to a two-step Tier model. For phenol-d_0, an energy flow is described by the intramolecularVR steps: "OH stretching level" → "doorway state" → "bath state". The intramolecularVR lifetime of phenol-d_0 is obtained to be 14 ps. On the other hand, the OD stretching vibration of phenol-d_1 exhibits quantum beats, followed by the intramolecularVR with a lifetime of 90 ps. In contrast, for the phenol-water complex, the intramolecularVR lifetime of OH(OD) stretch becomes 4.3 ps(12 ps) and an energy flow is described by the intramolecular and intermolecular processes, which lead to VP (vibratinal predisocciation). Although the energy difference is 1000 cm-1, no remarkable change of intermolecularVR and VP lifetimes is found in the hydrogen-bonded phenol-water complexes.

  2. A single pump cycling-column-switching technique coupled with homemade high exchange capacity columns for the determination of iodate in iodized edible salt by ion chromatography with UV detection.

    PubMed

    Huang, Zhongping; Subhani, Qamar; Zhu, Zuoyi; Guo, Weiqiang; Zhu, Yan

    2013-08-15

    A single pump cycling-column-switching technique has been developed for the iodate analysis in edible salt. Homemade high exchange capacity columns were adopted for the separation of iodate and chloride. Iodate could be retained and concentrated in a homemade concentrator column after eluents passing through the suppressor. With UV detection, iodate exhibited satisfactory linearity in the range of 0.1-10.0 mg/L with a correlation coefficient of 0.9996. The detection limit (LOD) was 45.53 μg/L, based on the signal-to-noise ratio of 3 (S/N=3) and a 100 μL injection volume. Relative standard deviations (RSDs) for retention time, peak area and peak height were all less than 2.1%. Recoveries of added iodate were in the range of 98.4-101.6% for the spiked samples. The quantitative determination of iodate in edible salt was accomplished by this column-switching technique, without any pretreatment and interference. The results on six samples were statistically compared with results determined by conventional titrimetric method. PMID:23561090

  3. Power converter

    NASA Technical Reports Server (NTRS)

    Black, J. M. (Inventor)

    1981-01-01

    A dc-to-dc converter employs four transistor switches in a bridge to chop dc power from a source, and a voltage multiplying diode rectifying ladder network to rectify and filter the chopped dc power for delivery to a load. The bridge switches are cross coupled in order for diagonally opposite pairs to turn on and off together using RC networks for the cross coupling to achieve the mode of operation of a free running multivibrator, and the diode rectifying ladder is configured to operate in a push-pull mode driven from opposite sides of the multivibrator outputs of the ridge switches. The four transistor switches provide a square-wave output voltage which as a peak-to-peak amplitude that is twice the input dc voltage, and is thus useful as a dc-to-ac inverter.

  4. Fluid Dynamics in Sucker Rod Pumps

    SciTech Connect

    Cutler, R.P.; Mansure, A.J.

    1999-01-14

    Sucker rod pumps are installed in approximately 90% of all oil wells in the U.S. Although they have been widely used for decades, there are many issues regarding the fluid dynamics of the pump that have not been fully investigated. A project was conducted at Sandia National Laboratories to develop unimproved understanding of the fluid dynamics inside a sucker rod pump. A mathematical flow model was developed to predict pressures in any pump component or an entire pump under single-phase fluid and pumping conditions. Laboratory flow tests were conducted on instrumented individual pump components and on a complete pump to verify and refine the model. The mathematical model was then converted to a Visual Basic program to allow easy input of fluid, geometry and pump parameters and to generate output plots. Examples of issues affecting pump performance investigated with the model include the effects of viscosity, surface roughness, valve design details, plunger and valve pressure differentials, and pumping rate.

  5. Convertible Stadium

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Air flotation technology used in NASA's Apollo program has found an interesting application in Hawaii's Aloha Stadium near Honolulu. The stadium's configuration can be changed, by moving entire 7,000-seat sections on a cushion of air, for best accommodation of spectators and participants at different types of events. In most stadiums, only a few hundred seats can be moved, by rolling sections on wheels or rails. At Aloha Stadium, 28,000 of the 50,000 seats can be repositioned for better spectator viewing and, additionally, for improved playing conditions. For example, a stadium designed primarily for football may compromise the baseball diamond by providing only a shallow outfield. Aloha's convertibility allows a full-size baseball field as well as optimum configurations for many other types of sports and special events. The photos show examples. The stadium owes its versatility to air flotation technology developed by General Motors. Its first large-scale application was movement of huge segments of the mammoth Saturn V moonbooster during assembly operations at Marshall Space Flight Center.

  6. Thermionic converter

    DOEpatents

    Rasor, Ned S.; Britt, Edward J.

    1976-01-01

    A gas-filled thermionic converter is provided with a collector and an emitter having a main emitter region and an auxiliary emitter region in electrical contact with the main emitter region. The main emitter region is so positioned with respect to the collector that a main gap is formed therebetween and the auxiliary emitter region is so positioned with respect to the collector that an auxiliary gap is formed therebetween partially separated from the main gap with access allowed between the gaps to allow ionizable gas in each gap to migrate therebetween. With heat applied to the emitter the work function of the auxiliary emitter region is sufficiently greater than the work function of the collector so that an ignited discharge occurs in the auxiliary gap and the work function of the main emitter region is so related to the work function of the collector that an unignited discharge occurs in the main gap sustained by the ions generated in the auxiliary gap. A current flows through a load coupled across the emitter and collector due to the unignited discharge in the main gap.

  7. PUMP CONSTRUCTION

    DOEpatents

    Strickland, G.; Horn, F.L.; White, H.T.

    1960-09-27

    A pump which utilizes the fluid being pumped through it as its lubricating fluid is described. This is achieved by means of an improved bearing construction in a pump of the enclosed or canned rotor type. At the outlet end of the pump, adjacent to an impeller mechanism, there is a bypass which conveys some of the pumped fluid to a chamber at the inlet end of the pump. After this chamber becomes full, the pumped fluid passes through fixed orifices in the top of the chamber and exerts a thrust on the inlet end of the pump rotor. Lubrication of the rotor shaft is accomplished by passing the pumped fluid through a bypass at the outlet end of the rotor shaft. This bypass conveys Pumped fluid to a cooling means and then to grooves on the surface of the rotor shait, thus lubricating the shaft.

  8. Fusion reactor pumped laser

    DOEpatents

    Jassby, Daniel L.

    1988-01-01

    A nuclear pumped laser capable of producing long pulses of very high power laser radiation is provided. A toroidal fusion reactor provides energetic neutrons which are slowed down by a moderator. The moderated neutrons are converted to energetic particles capable of pumping a lasing medium. The lasing medium is housed in an annular cell surrounding the reactor. The cell includes an annular reflecting mirror at the bottom and an annular output window at the top. A neutron reflector is disposed around the cell to reflect escaping neutrons back into the cell. The laser radiation from the annular window is focused onto a beam compactor which generates a single coherent output laser beam.

  9. Industrial Pumps

    NASA Technical Reports Server (NTRS)

    1986-01-01

    A flow inducer is a device that increases the pump intake capacity of a Worthington Centrifugal pump. It lifts the suction pressure sufficiently for the rotating main impeller of the centrifugal pump to operate efficiently at higher fluid intake levels. The concept derives from 1960's NASA technology which was advanced by Worthington Pump Division. The pumps are used to recirculate wood molasses, a highly viscous substance.

  10. UV inactivation of E. coli in liquid egg white

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An ultraviolet light (UV) system was developed to pasteurize liquid egg white. The system consisted of low-pressure mercury bulbs surrounded by UV transparent tubing. Egg white was inoculated with Escherichia coli K12 and pumped through the UV system at a flow rate of 330 ml/min. The effects of trea...

  11. Impact of UV-A radiation on erythemal UV and UV-index estimation over Korea

    NASA Astrophysics Data System (ADS)

    Park, Sang Seo; Lee, Yun Gon; Kim, Jung Hyun

    2015-12-01

    Because total UV (TUV) in the UV-A region is 100 times higher than in the UV-B region, UV-A is a considerable component when calculating erythemal UV (EUV) and UV-index. The ratio of EUV to TUV in the UV-A value [EUV(A)/TUV(A)] is investigated to convert the EUV(A) from TUV(A) for broadband observation. The representative value of EUV(A)/TUV(A), from the simulation study, is 6.9×10-4, changing from 6.1×10-4 to 7.0×10-4 as aerosol optical depth, total ozone and solar zenith angle change. By adopting the observational data of EUV(B) and TUV(A) from UV-biometer measurements at Yonsei University [(37.57°N, 126.95°E), 84 m above sea level], the EUV irradiance increases to 15% of EUV(B) due to the consideration of EUV(A) from the data of TUV(A) observation. Compared to the total EUV observed from the Brewer spectrophotometer at the same site, the EUV(B) from the UV-biometer observes only 95% of total EUV, and its underestimation is caused by neglecting the effect of UV-A. However, the sum of EUV(B) and EUV(A) [EUV(A+B)] from two UV-biometers is 10% larger than the EUV from the Brewer spectrophotometer because of the spectral overlap effect in the range 320-340 nm. The correction factor for the overlap effect adjusts 8% of total EUV.

  12. UV Induced Oxidation of Nitric Oxide

    NASA Technical Reports Server (NTRS)

    Parrish, Clyde, F. (Inventor); Luecke, Dale E. (Inventor)

    2007-01-01

    Nitric oxide in a gaseous stream is converted to nitrogen dioxide using oxidizing species generated at least in part using in situ UV radiation sources. The sources of the oxidizing species include oxygen and/or hydrogen peroxide. The oxygen may be a component of the gaseous stream or added to the gaseous stream, preferably near a UV radiation source, and is converted to ozone by the UV irradiation. The hydrogen peroxide is decomposed through a combination of vaporization and UV irradiation. The hydrogen peroxide is preferably stored at stable concentration levels, i.e., approximately 50% by volume and increased in concentration in a continuous process preceding vaporization within the flow channel of the gaseous stream and in the presence of the UV radiation sources.

  13. Casing pump

    SciTech Connect

    Bass, H.E.; Bass, R.E.

    1987-09-29

    A natural gas operated pump is described for use in the casing of an oil well, comprising: a tubular pump body having an open lower end for admitting well fluids to the interior of the pump body and an open upper end, wherein a downwardly facing seating surface is formed on the inner periphery of the pump body adjacent the upper end thereof; means for forming a seal between the pump body and the casing of the well; a rod extending longitudinally through the seating surface formed in the pump body and protruding from the upper end of the pump body; a valve member mounted on the rod below the seating surface and shaped to mate with the seating surface; and means for vertically positioning the rod in proportion to fluid pressure within the pump body.

  14. Magnetocaloric pump

    NASA Technical Reports Server (NTRS)

    Brown, G. V.

    1973-01-01

    Very cold liquids and gases such as helium, neon, and nitrogen can be pumped by using magnetocaloric effect. Adiabatic magnetization and demagnetization are used to alternately heat and cool slug of pumped fluid contained in closed chamber.

  15. Oxygen pumps

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Special considerations to be given to the design, fabrication, and use of centrifugal pumps for liquid O2 to avoid conditions that lead to system failure are given. Emphasis was placed on turbine pumps for flight applications.

  16. Long range target discrimination using UV fluorescence

    NASA Astrophysics Data System (ADS)

    Bray, Mark; Lepley, Jason

    2011-06-01

    An active imaging system using UV fluorescence for target discrimination is proposed. The emission wavelength is characteristic of the target material and allows spectral discrimination of targets from clutter. The burst-illumination-LIDAR system transmits a laser pulse and the fluorescent return is detected with a synchronised gated imaging receiver. The short gate length (~ns) allowed by a micro-channel plate CCD reduces solar clutter. Detector noise is not the limiting factor because of the high MCP-CCD detectivity. Laser choice is constrained by the required laser pulse energy, laser size and robustness. The COTS solution identified is a diode-pumped, 4th harmonic converted, 1064nm laser. Nd:YAG, Nd:YLF and Nd:Alexandrite lasers have superior performance but require some development for this application. A pessimistic range model evaluates the optical powers. Comparison of the received fluorescent energy to the detector noise equivalent energy and the solar energy received provides the detection range limit. Performance of the proposed systems exceeds the detection range requirement for all samples evaluated and all varying conditions explored. The lowest range is for black paint with the COTS laser system and is 2860m; the best ranges exceed 5km.

  17. ELECTROMAGNETIC PUMP

    DOEpatents

    Pulley, O.O.

    1954-08-17

    This patent reiates to electromagnetic pumps for electricity-conducting fluids and, in particular, describes several modifications for a linear conduction type electromagnetic interaction pump. The invention resides in passing the return conductor for the current traversing the fiuid in the duct back through the gap in the iron circuit of the pump. Both the maximum allowable pressure and the efficiency of a linear conduction electromagnetic pump are increased by incorporation of the present invention.

  18. Characterization of a Cyanobacterial Chloride-pumping Rhodopsin and Its Conversion into a Proton Pump.

    PubMed

    Hasemi, Takatoshi; Kikukawa, Takashi; Kamo, Naoki; Demura, Makoto

    2016-01-01

    Light-driven ion-pumping rhodopsins are widely distributed in microorganisms and are now classified into the categories of outward H(+) and Na(+) pumps and an inward Cl(-) pump. These different types share a common protein architecture and utilize the photoisomerization of the same chromophore, retinal, to evoke photoreactions. Despite these similarities, successful pump-to-pump conversion had been confined to only the H(+) pump bacteriorhodopsin, which was converted to a Cl(-) pump in 1995 by a single amino acid replacement. In this study we report the first success of the reverse conversion from a Cl(-) pump to a H(+) pump. A novel microbial rhodopsin (MrHR) from the cyanobacterium Mastigocladopsis repens functions as a Cl(-) pump and belongs to a cluster that is far distant from the known Cl(-) pumps. With a single amino acid replacement, MrHR is converted to a H(+) pump in which dissociable residues function almost completely in the H(+) relay reactions. MrHR most likely evolved from a H(+) pump, but it has not yet been highly optimized into a mature Cl(-) pump. PMID:26578511

  19. OSCILLATORY PUMP

    DOEpatents

    Underwood, N.

    1958-09-23

    This patent relates to a pump suitable fur pumping highly corrosive gases wherein no lubricant is needed in the pumping chamber thus eliminating possible contamination sources. The chamber contains a gas inlet and outlet in each side, with a paddle like piston suspended by a sylphon seal between these pcrts. An external arrangement causes the paddle to oscillate rapidly between the ports, alternately compressing and exhausting the gas trapped on each side of the paddle. Since the paddle does nnt touch the chamber sides at any point, no lubricant is required. This pump is useful for pumping large quantities of uranium hexafluorine.

  20. Feasibility study for convertible engine torque converter

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The feasibility study has shown that a dump/fill type torque converter has excellent potential for the convertible fan/shaft engine. The torque converter space requirement permits internal housing within the normal flow path of a turbofan engine at acceptable engine weight. The unit permits operating the engine in the turboshaft mode by decoupling the fan. To convert to turbofan mode, the torque converter overdrive capability bring the fan speed up to the power turbine speed to permit engagement of a mechanical lockup device when the shaft speed are synchronized. The conversion to turbofan mode can be made without drop of power turbine speed in less than 10 sec. Total thrust delivered to the aircraft by the proprotor, fan, and engine during tansient can be controlled to prevent loss of air speed or altitude. Heat rejection to the oil is low, and additional oil cooling capacity is not required. The turbofan engine aerodynamic design is basically uncompromised by convertibility and allows proper fan design for quiet and efficient cruise operation. Although the results of the feasibility study are exceedingly encouraging, it must be noted that they are based on extrapolation of limited existing data on torque converters. A component test program with three trial torque converter designs and concurrent computer modeling for fluid flow, stress, and dynamics, updated with test results from each unit, is recommended.

  1. Nuclear pumped gas laser research

    NASA Technical Reports Server (NTRS)

    Thom, K.

    1976-01-01

    Nuclear pumping of lasers by fission-fragments from nuclear chain reactions is discussed. Application of the newly developed lasers to spacecraft propulsion or onboard power, to lunar bases for industrial processing, and to earth for utilization of power without pollution and hazards is envisioned. Emphasis is placed on the process by which the fission-fragement kinetic energy is converted into laser light.

  2. 50-kHz, 50-ns UV pulse generation by diode-pumped frequency doubling Pr3+:YLF Q-switch laser with a Cr4+:YAG saturable absorber.

    PubMed

    Tanaka, Hiroki; Kariyama, Ryosuke; Iijima, Kodai; Kannari, Fumihiko

    2016-08-10

    We demonstrate intracavity second-harmonic generation at 320 nm of a diode-pumped praseodymium-doped YLF laser Q-switched by a Cr4+:YAG crystal. By employing two 3.5-W high-power blue InGaN diode lasers as the pump source, we obtained 50-ns Q-switched pulses with a pulse energy of 1.54 μJ at a repetition rate of 50 kHz. A rate equation analysis shows good agreement with the experimental results. PMID:27534459

  3. Filter-free wavelength converter using Sagnac loop and delayed interferometer

    NASA Astrophysics Data System (ADS)

    Tsuji, K.; Yamaguchi, T.; Onodera, N.; Saruwatari, M.

    2006-01-01

    A filter-free fiber-XPM-based wavelength converter is proposed and experimentally demonstrated without conventional bandpass optical filters used to filter out the converted signal. The converter is constructed with a propagation-diversity Sagnac loop to separate a converted signal from a pump signal and a delayed interferometer to covert the XPM signal into intensity modulation. We show that 10-Gbit/s input signals are successfully converted to signals with allotted wavelengths by our proposed scheme.

  4. Ferroelectric Pump

    NASA Technical Reports Server (NTRS)

    Jalink, Antony, Jr. (Inventor); Hellbaum, Richard F. (Inventor); Rohrbach, Wayne W. (Inventor)

    2000-01-01

    A ferroelectric pump has one or more variable volume pumping chambers internal to a housing. Each chamber has at least one wall comprising a dome shaped internally prestressed ferroelectric actuator having a curvature and a dome height that varies with an electric voltage applied between an inside and outside surface of the actuator. A pumped medium flows into and out of each pumping chamber in response to displacement of the ferroelectric actuator. The ferroelectric actuator is mounted within each wall and isolates each ferroelectric actuator from the pumped medium, supplies a path for voltage to be applied to each ferroelectric actuator, and provides for positive containment of each ferroelectric actuator while allowing displacement of the entirety of each ferroelectric actuator in response to the applied voltage.

  5. Axial Pump

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J., Jr. (Inventor); Akkerman, James W. (Inventor); Aber, Gregory S. (Inventor); VanDamm, George Arthur (Inventor); Bacak, James W. (Inventor); Svejkovsky, Paul A. (Inventor); Benkowski, Robert J. (Inventor)

    1997-01-01

    A rotary blood pump includes a pump housing for receiving a flow straightener, a rotor mounted on rotor bearings and having an inducer portion and an impeller portion, and a diffuser. The entrance angle, outlet angle, axial and radial clearances of blades associated with the flow straightener, inducer portion, impeller portion and diffuser are optimized to minimize hemolysis while maintaining pump efficiency. The rotor bearing includes a bearing chamber that is filled with cross-linked blood or other bio-compatible material. A back emf integrated circuit regulates rotor operation and a microcomputer may be used to control one or more back emf integrated circuits. A plurality of magnets are disposed in each of a plurality of impeller blades with a small air gap. A stator may be axially adjusted on the pump housing to absorb bearing load and maximize pump efficiency.

  6. Fusion reactor pumped laser

    DOEpatents

    Jassby, D.L.

    1987-09-04

    A nuclear pumped laser capable of producing long pulses of very high power laser radiation is provided. A toroidal fusion reactor provides energetic neutrons which are slowed down by a moderator. The moderated neutrons are converted to energetic particles capable of pumping a lasing medium. The lasing medium is housed in an annular cell surrounding the reactor. The cell includes an annular reflecting mirror at the bottom and an annular output window at the top. A neutron reflector is disposed around the cell to reflect escaping neutrons back into the cell. The laser radiation from the annular window is focused onto a beam compactor which generates a single coherent output laser beam. 10 figs.

  7. Vacuum pump aids ejectors

    SciTech Connect

    Nelson, R.E.

    1982-12-01

    The steam ejector/vacuum pump hybrid system has been operating satisfactorily since the summer of 1981. This system has essentially been as troublefree as the all-ejector system and, of course, has provided a substantial cost savings. Construction is currently under way to convert the vacuum system of another crude still which is equipped with steam ejectors and barometric condensers to the hybrid system of steam ejectors, surface condensers, and vacuum pumps. This current project is even more financially attractive because it allows a dirty water cooling tower which serves the barometric condensers to be shut down. Providing a vacuum for crude distillation vacuum towers with this hybrid system is by no means the only application of this technique. Any vacuum system consisting of all steam ejectors would be a candidate for this hybrid system and the resulting savings in energy.

  8. Rotorcraft convertible engine study

    NASA Technical Reports Server (NTRS)

    Gill, J. C.; Earle, R. V.; Mar, H. M.

    1982-01-01

    The objective of the Rotorcraft Convertible Engine Study was to define future research and technology effort required for commercial development by 1988 of convertible fan/shaft gas turbine engines for unconventional rotorcraft transports. Two rotorcraft and their respective missions were defined: a Fold Tilt Rotor aircraft and an Advancing Blade Concept (ABC) rotorcraft. Sensitivity studies were conducted with these rotorcraft to determine parametrically the influence of propulsion characteristics on aircraft size, mission fuel requirements, and direct operating costs (DOC). The two rotorcraft were flown with conventional propulsion systems (separate lift/cruise engines) and with convertible propulsion systems to determine the benefits to be derived from convertible engines. Trade-off studies were conducted to determine the optimum engine cycle and staging arrangement for a convertible engine. Advanced technology options applicable to convertible engines were studied. Research and technology programs were identified which would ensure technology readiness for commercial development of convertible engines by 1988.

  9. Method for controlling powertrain pumps

    DOEpatents

    Sime, Karl Andrew; Spohn, Brian L; Demirovic, Besim; Martini, Ryan D; Miller, Jean Marie

    2013-10-22

    A method of controlling a pump supplying a fluid to a transmission includes sensing a requested power and an excess power for a powertrain. The requested power substantially meets the needs of the powertrain, while the excess power is not part of the requested power. The method includes sensing a triggering condition in response to the ability to convert the excess power into heat in the transmission, and determining that an operating temperature of the transmission is below a maximum. The method also includes determining a calibrated baseline and a dissipation command for the pump. The calibrated baseline command is configured to supply the fluid based upon the requested power, and the dissipation command is configured to supply additional fluid and consume the excess power with the pump. The method operates the pump at a combined command, which is equal to the calibrated baseline command plus the dissipation command.

  10. Enhancing the efficiency of silicon Raman converters

    NASA Astrophysics Data System (ADS)

    Vermeulen, Nathalie; Sipe, John E.; Thienpont, Hugo

    2010-05-01

    We propose a silicon ring Raman converter in which the spatial variation of the Raman gain along the ring for TE polarization is used to quasi-phase-match the CARS process. If in addition the pump, Stokes, and anti-Stokes waves involved in the CARS interaction are resonantly enhanced by the ring structure, the Stokes-to-anti-Stokes conversion efficiency can be increased by at least four orders of magnitude over that of one-dimensional perfectly phase-matched silicon Raman converters, and can reach values larger than unity with relatively low input pump intensities. These improvements in conversion performance could substantially expand the practical applicability of the CARS process for optical wavelength conversion.

  11. Submersible pump

    SciTech Connect

    Todd, D. B.

    1985-08-27

    A method and apparatus for using a submersible pump to lift reservoir fluids in a well while having the tubing/casing annulus isolated from the produced fluids. The apparatus allows the submersible pump to be positioned above the annular packoff device. The apparatus comprises an outer shield that encloses the pump and can be attached to the production tubing. The lower end of the shield attaches to a short tubing section that seals with the annular packoff device or a receptacle above the annular packoff device.

  12. An economic evaluation comparison of solar water pumping system with engine pumping system for rice cultivation

    NASA Astrophysics Data System (ADS)

    Treephak, Kasem; Thongpron, Jutturit; Somsak, Dhirasak; Saelao, Jeerawan; Patcharaprakiti, Nopporn

    2015-08-01

    In this paper we propose the design and economic evaluation of the water pumping systems for rice cultivation using solar energy, gasoline fuel and compare both systems. The design of the water and gasoline engine pumping system were evaluated. The gasoline fuel cost used in rice cultivation in an area of 1.6 acres. Under same conditions of water pumping system is replaced by the photovoltaic system which is composed of a solar panel, a converter and an electric motor pump which is compose of a direct current (DC) motor or an alternating current (AC) motor with an inverter. In addition, the battery is installed to increase the efficiency and productivity of rice cultivation. In order to verify, the simulation and economic evaluation of the storage energy battery system with batteries and without batteries are carried out. Finally the cost of four solar pumping systems was evaluated and compared with that of the gasoline pump. The results showed that the solar pumping system can be used to replace the gasoline water pumping system and DC solar pump has a payback less than 10 years. The systems that can payback the fastest is the DC solar pumping system without batteries storage system. The system the can payback the slowest is AC solar pumping system with batteries storage system. However, VAC motor pump of 220 V can be more easily maintained than the motor pump of 24 VDC and batteries back up system can supply a more stable power to the pump system.

  13. High power diode pumped alkali vapor lasers

    NASA Astrophysics Data System (ADS)

    Zweiback, J.; Krupke, B.

    2008-05-01

    Diode pumped alkali lasers have developed rapidly since their first demonstration. These lasers offer a path to convert highly efficient, but relatively low brightness, laser diodes into a single high power, high brightness beam. General Atomics has been engaged in the development of DPALs with scalable architectures. We have examined different species and pump characteristics. We show that high absorption can be achieved even when the pump source bandwidth is several times the absorption bandwidth. In addition, we present experimental results for both potassium and rubidium systems pumped with a 0.2 nm bandwidth alexandrite laser. These data show slope efficiencies of 67% and 72% respectively.

  14. ION PUMP

    DOEpatents

    Milleron, N.

    1961-01-01

    An ion pump and pumping method are given for low vacuum pressures in which gases introduced into a pumping cavity are ionized and thereafter directed and accelerated into a quantity of liquid gettering metal where they are absorbed. In the preferred embodiment the metal is disposed as a liquid pool upon one electrode of a Phillips ion gauge type pump. Means are provided for continuously and remotely withdrawing and degassing the gettering metal. The liquid gettering metal may be heated if desired, although various combinations of gallium, indium, tin, bismuth, and lead, the preferred metals, have very low melting points. A background pressure of evaporated gettering metal may be provided by means of a resistance heated refractory metal wick protruding from the surface of the pcol of gettering metal.

  15. Electrokinetic pump

    DOEpatents

    Patel, Kamlesh D.

    2007-11-20

    A method for altering the surface properties of a particle bed. In application, the method pertains particularly to an electrokinetic pump configuration where nanoparticles are bonded to the surface of the stationary phase to alter the surface properties of the stationary phase including the surface area and/or the zeta potential and thus improve the efficiency and operating range of these pumps. By functionalizing the nanoparticles to change the zeta potential the electrokinetic pump is rendered capable of operating with working fluids having pH values that can range from 2-10 generally and acidic working fluids in particular. For applications in which the pump is intended to handle highly acidic solutions latex nanoparticles that are quaternary amine functionalized can be used.

  16. The photoelectric displacement converter

    NASA Astrophysics Data System (ADS)

    Dragoner, Valeriu V.

    2005-02-01

    In the article are examined questions of constructing photoelectric displacement converter satisfying demands that are stated above. Converter has channels of approximate and precise readings. The approximate reading may be accomplished either by the method of reading from a code mask or by the method of the consecutive calculation of optical scale gaps number. Phase interpolator of mouar strips" gaps is determined as a precise measuring. It is shown mathematical model of converter that allow evaluating errors and operating speed of conversion.

  17. ITER convertible blanket evaluation

    SciTech Connect

    Wong, C.P.C.; Cheng, E.

    1995-09-01

    Proposed International Thermonuclear Experimental Reactor (ITER) convertible blankets were reviewed. Key design difficulties were identified. A new particle filter concept is introduced and key performance parameters estimated. Results show that this particle filter concept can satisfy all of the convertible blanket design requirements except the generic issue of Be blanket lifetime. If the convertible blanket is an acceptable approach for ITER operation, this particle filter option should be a strong candidate.

  18. Interleaved power converter

    DOEpatents

    Zhu, Lizhi

    2007-11-13

    A power converter architecture interleaves full bridge converters to alleviate thermal management problems in high current applications, and may, for example, double the output power capability while reducing parts count and costs. For example, one phase of a three phase inverter is shared between two transformers, which provide power to a rectifier such as a current doubler rectifier to provide two full bridge DC/DC converters with three rather than four high voltage inverter legs.

  19. Laser system with trivalent chromium doped aluminum tungstate fluorescent converter

    SciTech Connect

    Dube, G.

    1988-09-06

    This patent describes a laser system combination comprising: (a) a neodymium element; (b) a light source for pumping the neodymium laser element to produce coherent, monochromatic light; (c) a fluorescent converter element positioned in light exchange relationship with the light source for spectrally shifting at least a portion of light outside of the neodymium laser pumping band passing through the neodymium laser into light in the neodymium laser pumping band; (d) the fluorescent element including trivalent chromium doped aluminum tungstate excited by light passing through the laser which is outside of the pumping band for the laser, the tungstate covering a portion of light passing through the laser element which is outside of the pumping band into light within the pumping band; (e) the concentration of the trivalent chromium dopant lying in the range of 0.5 to 3 per mole percent (%).

  20. Photocapacitive image converter

    NASA Technical Reports Server (NTRS)

    Miller, W. E.; Sher, A.; Tsuo, Y. H. (Inventor)

    1982-01-01

    An apparatus for converting a radiant energy image into corresponding electrical signals including an image converter is described. The image converter includes a substrate of semiconductor material, an insulating layer on the front surface of the substrate, and an electrical contact on the back surface of the substrate. A first series of parallel transparent conductive stripes is on the insulating layer with a processing circuit connected to each of the conductive stripes for detecting the modulated voltages generated thereon. In a first embodiment of the invention, a modulated light stripe perpendicular to the conductive stripes scans the image converter. In a second embodiment a second insulating layer is deposited over the conductive stripes and a second series of parallel transparent conductive stripes perpendicular to the first series is on the second insulating layer. A different frequency current signal is applied to each of the second series of conductive stripes and a modulated image is applied to the image converter.

  1. UV inactivation of bacteria in apple cider.

    PubMed

    Geveke, David J

    2005-08-01

    Apple cider, inoculated with Escherichia coli and Listeria innocua, was processed using a simple UV apparatus. The apparatus consisted of a low-pressure mercury lamp surrounded by a coil of UV transparent tubing. Cider was pumped through the tubing at flow rates of 27 to 83 ml/min. The population of E. coli K-12 was reduced by 3.4 +/- 0.3 log after being exposed for 19 s at a treatment temperature of 25 degrees C. The population of L. innocua, which was more resistant to UV, was reduced by 2.5 +/- 0.1 log after being exposed for 58 s. The electrical energy for the process was 34 J/ml and is similar to that for conventional thermal processing. UV processing has the potential to improve the safety and extend the shelf life of apple cider. PMID:21132989

  2. Cascaded resonant bridge converters

    NASA Technical Reports Server (NTRS)

    Stuart, Thomas A. (Inventor)

    1989-01-01

    A converter for converting a low voltage direct current power source to a higher voltage, high frequency alternating current output for use in an electrical system where it is desired to use low weight cables and other circuit elements. The converter has a first stage series resonant (Schwarz) converter which converts the direct current power source to an alternating current by means of switching elements that are operated by a variable frequency voltage regulator, a transformer to step up the voltage of the alternating current, and a rectifier bridge to convert the alternating current to a direct current first stage output. The converter further has a second stage series resonant (Schwarz) converter which is connected in series to the first stage converter to receive its direct current output and convert it to a second stage high frequency alternating current output by means of switching elements that are operated by a fixed frequency oscillator. The voltage of the second stage output is controlled at a relatively constant value by controlling the first stage output voltage, which is accomplished by controlling the frequency of the first stage variable frequency voltage controller in response to second stage voltage. Fault tolerance in the event of a load short circuit is provided by making the operation of the first stage variable frequency voltage controller responsive to first and second stage current limiting devices. The second stage output is connected to a rectifier bridge whose output is connected to the input of the second stage to provide good regulation of output voltage wave form at low system loads.

  3. Electrokinetic pump

    DOEpatents

    Hencken, Kenneth R.; Sartor, George B.

    2004-08-03

    An electrokinetic pump in which the porous dielectric medium of conventional electrokinetic pumps is replaced by a patterned microstructure. The patterned microstructure is fabricated by lithographic patterning and etching of a substrate and is formed by features arranged so as to create an array of microchannels. The microchannels have dimensions on the order of the pore spacing in a conventional porous dielectric medium. Embedded unitary electrodes are vapor deposited on either end of the channel structure to provide the electric field necessary for electroosmotic flow.

  4. Insulin pumps.

    PubMed

    Pickup, J

    2011-02-01

    The last year has seen a continued uptake of insulin pump therapy in most countries. The USA is still a leader in pump use, with probably some 40% of type 1 diabetic patients on continuous subcutaneous insulin infusion (CSII), but the large variation in usage within Europe remains, with relatively high use (> 15%) in, for example, Norway, Austria, Germany and Sweden and low use (< 5%) in Spain, the UK, Finland and Portugal. There is much speculation on the factors responsible for this variation, and the possibilities include physician attitudes to CSII and knowledge about its benefits and indications for its use (and inappropriate beliefs about dangers), the availability of reimbursement from insurance companies or funding from national health services, the availability of sufficient diabetes nurse educators and dietitians trained in pump procedures, and clear referral pathways for the pump candidate from general practitioner or general hospital to specialist pump centre. There are now several comprehensive national guidelines on CSII use (see ATTD Yearbook 2009) but more work needs to be done in unifying uptake and ensuring all those who can benefit do so. Technology developments recently include increasing use of pumps with continuous glucose monitoring (CGM) connectivity (see elsewhere in this volume) and the emergence of numerous manufacturers developing so-called 'patch pumps', often for the type 2 diabetes market. Interestingly, the evidence base for CSII in this group is not well established, and for this reason the selected papers on CSII in this section include several in this area. The use of CSII in diabetic pregnancy is a long-established practice, in spite of the lack of evidence that it is superior to multiple daily injections (MDI), and few randomised controlled trials have been done in recent years. Several papers in this field this year continue the debate about the usefulness of CSII in diabetic pregnancy and are reviewed here. It is pleasing

  5. DIFFUSION PUMP

    DOEpatents

    Levenson, L.

    1963-09-01

    A high-vacuum diffusion pump is described, featuring a novel housing geometry for enhancing pumping speed. An upright, cylindrical lower housing portion is surmounted by a concentric, upright, cylindrical upper housing portion of substantially larger diameter; an uppermost nozzle, disposed concentrically within the upper portion, is adapted to eject downwardly a conical sheet of liquid outwardly to impinge upon the uppermost extremity of the interior wall of the lower portion. Preferably this nozzle is mounted upon a pedestal rising coaxially from within the lower portion and projecting up into said upper portion. (AEC)

  6. Color-tunable properties and energy transfer in Ba3GdNa(PO4)3F:Eu2+, Tb3+ phosphor pumped for n-UV w-LEDs

    NASA Astrophysics Data System (ADS)

    Zeng, Chao; Liu, Haikun; Hu, Yingmo; Liao, Libing; Mei, Lefu

    2015-11-01

    A series of Eu2+ and Eu2+/Tb3+ co-doped Ba3GdNa(PO4)3F phosphors have been synthesized via a high temperature solid-state reaction. The relative intensity of PL spectra of Ba3GdNa(PO4)3F:xEu2+ increases with increasing x value, and reaches a maximum at x=0.04. Ba3GdNa(PO4)3F:Eu2+, Tb3+ phosphors exhibit a broad excitation band ranging from 220 to 450 nm, which matches perfectly with the characteristic emission of n-UV light-emitting diode (LED) chips. Upon 365 nm excitation, the Ba3GdNa(PO4)3F:Eu2+, Tb3+ phosphors show two dominating bands peaked at 466 and 543 nm, which are assigned to the 4f7→4f65d1 transition of the Eu2+ ions and the 5D4→7F5 transition of the Tb3+ ions, respectively. In view of the energy transfer mechanism between Eu2+ and Tb3+, the Ba3GdNa(PO4)3F:Eu2+, Tb3+ emission color can adjust from blue to green, and their chromatic coordinates (x, y) vary from (0.16, 0.135) to (0.254, 0.398). The critical distance was also calculated to be 16.90 Å. The above results indicate that the Ba3GdNa(PO4)3F: Eu2+, Tb3+ phosphors are a candidate for blue-green components in the application of n-UV w-LEDs.

  7. Microminiature thermionic converters

    SciTech Connect

    King, Donald B.; Sadwick, Laurence P.; Wernsman, Bernard R.

    2001-09-25

    Microminiature thermionic converts (MTCs) having high energy-conversion efficiencies and variable operating temperatures. Methods of manufacturing those converters using semiconductor integrated circuit fabrication and micromachine manufacturing techniques are also disclosed. The MTCs of the invention incorporate cathode to anode spacing of about 1 micron or less and use cathode and anode materials having work functions ranging from about 1 eV to about 3 eV. Existing prior art thermionic converter technology has energy conversion efficiencies ranging from 5-15%. The MTCs of the present invention have maximum efficiencies of just under 30%, and thousands of the devices can be fabricated at modest costs.

  8. Monolithic solid electrolyte oxygen pump

    DOEpatents

    Fee, Darrell C.; Poeppel, Roger B.; Easler, Timothy E.; Dees, Dennis W.

    1989-01-01

    A multi-layer oxygen pump having a one-piece, monolithic ceramic structure affords high oxygen production per unit weight and volume and is thus particularly adapted for use as a portable oxygen supply. The oxygen pump is comprised of a large number of small cells on the order of 1-2 millimeters in diameter which form the walls of the pump and which are comprised of thin, i.e., 25-50 micrometers, ceramic layers of cell components. The cell components include an air electrode, an oxygen electrode, an electrolyte and interconnection materials. The cell walls form the passages for input air and for exhausting the oxygen which is transferred from a relatively dilute gaseous mixture to a higher concentration by applying a DC voltage across the electrodes so as to ionize the oxygen at the air electrode, whereupon the ionized oxygen travels through the electrolyte and is converted to oxygen gas at the oxygen electrode.

  9. 18. Electrically driven pumps in Armory Street Pump House. Pumps ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Electrically driven pumps in Armory Street Pump House. Pumps in background formerly drew water from the clear well. They went out of service when use of the beds was discontinued. Pumps in the foreground provide high pressure water to Hamden. - Lake Whitney Water Filtration Plant, Armory Street Pumphouse, North side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  10. Converting Nonclassicality into Entanglement.

    PubMed

    Killoran, N; Steinhoff, F E S; Plenio, M B

    2016-02-26

    Quantum mechanics exhibits a wide range of nonclassical features, of which entanglement in multipartite systems takes a central place. In several specific settings, it is well known that nonclassicality (e.g., squeezing, spin squeezing, coherence) can be converted into entanglement. In this work, we present a general framework, based on superposition, for structurally connecting and converting nonclassicality to entanglement. In addition to capturing the previously known results, this framework also allows us to uncover new entanglement convertibility theorems in two broad scenarios, one which is discrete and one which is continuous. In the discrete setting, the classical states can be any finite linearly independent set. For the continuous setting, the pertinent classical states are "symmetric coherent states," connected with symmetric representations of the group SU(K). These results generalize and link convertibility properties from the resource theory of coherence, spin coherent states, and optical coherent states, while also revealing important connections between local and nonlocal pictures of nonclassicality. PMID:26967398

  11. Digital scale converter

    DOEpatents

    Upton, Richard G.

    1978-01-01

    A digital scale converter is provided for binary coded decimal (BCD) conversion. The converter may be programmed to convert a BCD value of a first scale to the equivalent value of a second scale according to a known ratio. The value to be converted is loaded into a first BCD counter and counted down to zero while a second BCD counter registers counts from zero or an offset value depending upon the conversion. Programmable rate multipliers are used to generate pulses at selected rates to the counters for the proper conversion ratio. The value present in the second counter at the time the first counter is counted to the zero count is the equivalent value of the second scale. This value may be read out and displayed on a conventional seven-segment digital display.

  12. Effect of UV irradiation on evaporated ZnS films

    NASA Technical Reports Server (NTRS)

    Hass, G.; Heaney, J. B.; Hunter, W. R.; Angel, D. W.

    1980-01-01

    Evaporated ZnS films used as a component in reflectance enhancing or decreasing multilayer coatings for mirrors, transparent optical materials, and vacuum UV reflecting optics, are investigated with reference to the reflectance loss under UV irradiation and the formation of ZnO as a result of the decomposition of ZnS in the presence of oxygen. Reflectance measurements over a broad wavelength range reveal that the UV induced reflectance losses are generally restricted to wavelengths shorter than 4000 A and are most severe in the vacuum UV region. After 134 hr of UV exposure initially polycrystalline film of 150-200 A thick is completely converted to amorphous ZnO. The results demonstrate that caution should be exercised in employing ZnS as the outer layer in an optical coating system designed for use in the UV and vacuum UV regions.

  13. High average power quasi-CW single-mode green and UV fiber lasers

    NASA Astrophysics Data System (ADS)

    Avdokhin, Alexey; Gapontsev, Valentin; Kadwani, Pankaj; Vaupel, Andreas; Samartsev, Igor; Platonov, Nicholai; Yusim, Alex; Myasnikov, Daniil

    2015-02-01

    Kilowatt-level narrow-linewidth SM ytterbium fiber laser operating in high-repetition-rate QCW regime was used to obtain 700 W average power at 532 nm with single-mode beam quality and wall-plug efficiency of over 23 %. To the best of our knowledge, this is ~60 % higher power than previously reported for single-mode green lasers based on other platforms, and also is ~30 % increase comparing to the previous result obtained by our group on the base of similar fiber laser platform. We have also experimentally proved that the same type of fiber laser can be used for generating of world-record levels of power at other wavelengths of visible and UV spectral ranges by employing cascaded non-linear frequency conversion. Thus, utilizing frequency tripling in 2 LBO crystals, we achieved over 160 W average power of nearly single-mode UV light at 355 nm with THG efficiency of more than 25 %. As far as we know, this is the highest output power ever reported for UV laser with nearly diffraction limited beam quality. We also conducted some preliminary experiments to demonstrate suitability of our approach for generating longer wavelengths of the visible spectrum. By pre-shifting fundamental emission wavelength in fiber Raman converter, followed by frequency doubling in NCPM LBO, we obtained average powers of 36 W at 589 nm and 27 W at 615 nm. These proof-of-concept experiments were performed with low-power pump laser and were not fully optimized with respect to frequency conversion. Our analysis indicates that employing kW-level QCW ytterbium laser with optimized SRS and SHG converters we can achieve hundreds of Watts of average power in red and orange color with single-mode beam quality.

  14. Thermionic photovoltaic energy converter

    NASA Technical Reports Server (NTRS)

    Chubb, D. L. (Inventor)

    1985-01-01

    A thermionic photovoltaic energy conversion device comprises a thermionic diode mounted within a hollow tubular photovoltaic converter. The thermionic diode maintains a cesium discharge for producing excited atoms that emit line radiation in the wavelength region of 850 nm to 890 nm. The photovoltaic converter is a silicon or gallium arsenide photovoltaic cell having bandgap energies in this same wavelength region for optimum cell efficiency.

  15. Neutron-pumped excimer flashlamp sources

    NASA Astrophysics Data System (ADS)

    Miley, George H.; Prelas, Mark A.

    2004-01-01

    A Nuclear Pumped Flashlamp (NPF) is closely related to a Nuclear-Pumped Laser NPL in that both use nuclear radiation to excite the medium. The NPF does not require as high peak power as is needed for NPL inversion. Still, with a reactor source, a large volume NPF can be designed to deliver extremely large fluorescence in the UV up to the infrared range, depending on the media employed. The NPF can then be used for industrial applications or for pumping a laser requiring a high intensity light pump. The first experimental example of this approach was a 3He-XeBr2 NPF employed in 1993 to pump a small iodine laser. The present paper discusses issues involved in scaling such a NPF up to an ultra high energy output.

  16. Probing cis-trans isomerization in the S{sub 1} state of C{sub 2}H{sub 2} via H-atom action and hot band-pumped IR-UV double resonance spectroscopies

    SciTech Connect

    Changala, P. Bryan; Baraban, Joshua H.; Field, Robert W.; Merer, Anthony J.

    2015-08-28

    We report novel experimental strategies that should prove instrumental in extending the vibrational and rotational assignments of the S{sub 1} state of acetylene, C{sub 2}H{sub 2}, in the region of the cis-trans isomerization barrier. At present, the assignments are essentially complete up to ∼500 cm{sup −1} below the barrier. Two difficulties arise when the assignments are continued to higher energies. One is that predissociation into C{sub 2}H + H sets in roughly 1100 cm{sup −1} below the barrier; the resulting quenching of laser-induced fluorescence (LIF) reduces its value for recording spectra in this region. The other difficulty is that tunneling through the barrier causes a staggering in the K-rotational structure of isomerizing vibrational levels. The assignment of these levels requires data for K values up to at least 3. Given the rotational selection rule K′ − ℓ{sup ′′} = ± 1, such data must be obtained via excited vibrational levels of the ground state with ℓ{sup ′′} > 0. In this paper, high resolution H-atom resonance-enhanced multiphoton ionization spectra are demonstrated to contain predissociated bands which are almost invisible in LIF spectra, while preliminary data using a hyperthermal pulsed nozzle show that ℓ{sup ′′} = 2 states can be selectively populated in a jet, giving access to K′ = 3 states in IR-UV double resonance.

  17. Probing cis-trans isomerization in the S1 state of C2H2 via H-atom action and hot band-pumped IR-UV double resonance spectroscopies.

    PubMed

    Changala, P Bryan; Baraban, Joshua H; Merer, Anthony J; Field, Robert W

    2015-08-28

    We report novel experimental strategies that should prove instrumental in extending the vibrational and rotational assignments of the S1 state of acetylene, C2H2, in the region of the cis-trans isomerization barrier. At present, the assignments are essentially complete up to ∼500 cm(-1) below the barrier. Two difficulties arise when the assignments are continued to higher energies. One is that predissociation into C2H + H sets in roughly 1100 cm(-1) below the barrier; the resulting quenching of laser-induced fluorescence (LIF) reduces its value for recording spectra in this region. The other difficulty is that tunneling through the barrier causes a staggering in the K-rotational structure of isomerizing vibrational levels. The assignment of these levels requires data for K values up to at least 3. Given the rotational selection rule K' - ℓ('') = ± 1, such data must be obtained via excited vibrational levels of the ground state with ℓ('') > 0. In this paper, high resolution H-atom resonance-enhanced multiphoton ionization spectra are demonstrated to contain predissociated bands which are almost invisible in LIF spectra, while preliminary data using a hyperthermal pulsed nozzle show that ℓ('') = 2 states can be selectively populated in a jet, giving access to K' = 3 states in IR-UV double resonance. PMID:26328846

  18. Probing cis-trans isomerization in the S1 state of C2H2 via H-atom action and hot band-pumped IR-UV double resonance spectroscopies

    NASA Astrophysics Data System (ADS)

    Changala, P. Bryan; Baraban, Joshua H.; Merer, Anthony J.; Field, Robert W.

    2015-08-01

    We report novel experimental strategies that should prove instrumental in extending the vibrational and rotational assignments of the S1 state of acetylene, C2H2, in the region of the cis-trans isomerization barrier. At present, the assignments are essentially complete up to ˜500 cm-1 below the barrier. Two difficulties arise when the assignments are continued to higher energies. One is that predissociation into C2H + H sets in roughly 1100 cm-1 below the barrier; the resulting quenching of laser-induced fluorescence (LIF) reduces its value for recording spectra in this region. The other difficulty is that tunneling through the barrier causes a staggering in the K-rotational structure of isomerizing vibrational levels. The assignment of these levels requires data for K values up to at least 3. Given the rotational selection rule K' - ℓ'' = ± 1, such data must be obtained via excited vibrational levels of the ground state with ℓ'' > 0. In this paper, high resolution H-atom resonance-enhanced multiphoton ionization spectra are demonstrated to contain predissociated bands which are almost invisible in LIF spectra, while preliminary data using a hyperthermal pulsed nozzle show that ℓ'' = 2 states can be selectively populated in a jet, giving access to K' = 3 states in IR-UV double resonance.

  19. Development of the sonic pump levitation

    NASA Technical Reports Server (NTRS)

    Dunn, S. A.

    1984-01-01

    A prototype levitating/positioning device termed the Sonic Pump Levitator was designed, built and successfully tested in full gravity and in the reduced gravity of the parabolic flight regime of the KC-135. Positioning is achieved by timely and appropriate application of gas momentum from one or more of six sonic pumps. The sonic pumps, which are arranged orthogonally in opposed pairs about the levitation region, are activated by an electro-optical, computer controlled, feedback system. The sonic pump is a transducer which is capable of converting sound energy into a directed flow of gas. It consists of a loudspeaker whose face is sealed by a closure perforated by one or more orifices. The diaphragm of the loudspeaker is the only moving part of the sonic pump, no valves being needed. This very low inertia electromechanical device was developed to provide the short response time necessary to keep pace with the demands of computerized position keeping.

  20. Lasant Materials for Blackbody-Pumped Lasers

    NASA Technical Reports Server (NTRS)

    Deyoung, R. J. (Editor); Chen, K. Y. (Editor)

    1985-01-01

    Blackbody-pumped solar lasers are proposed to convert sunlight into laser power to provide future space power and propulsion needs. There are two classes of blackbody-pumped lasers. The direct cavity-pumped system in which the lasant molecule is vibrationally excited by the absorption of blackbody radiation and laser, all within the blackbody cavity. The other system is the transfer blackbody-pumped laser in which an absorbing molecule is first excited within the blackbody cavity, then transferred into a laser cavity when an appropriate lasant molecule is mixed. Collisional transfer of vibrational excitation from the absorbing to the lasing molecule results in laser emission. A workshop was held at NASA Langley Research Center to investigate new lasant materials for both of these blackbody systems. Emphasis was placed on the physics of molecular systems which would be appropriate for blackbody-pumped lasers.

  1. UV water disinfector

    DOEpatents

    Gadgil, A.; Garud, V.

    1998-07-14

    A UV disinfector with a gravity driven feed water delivery system and an air-suspended bare UV lamp are disclosed. The disinfector is hydrodynamically optimized with a laminerizing, perforated baffle wall, beveled treatment chamber, and outlet weir. 7 figs.

  2. UV water disinfector

    DOEpatents

    Gadgil, Ashok; Garud, Vikas

    1998-07-14

    A UV disinfector with a gravity driven feed water delivery system, and an air-suspended bare UV lamp. The disinfector is hydrodynamically optimized with a laminerizing, perforated baffle wall, beveled treatment chamber, and outlet weir.

  3. 69. VIEW, LOOKING NORTHEAST, OF PUMP LOCATED ON THE MIANUS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    69. VIEW, LOOKING NORTHEAST, OF PUMP LOCATED ON THE MIANUS RIVER DOCK. THE PUMP WAS ORIGINALLY POWERED BY STEAM AND LATER CONVERTED TO ELECTRICAL OPERATION. IT WAS USED TO PROVIDE A HIGH PRESSURE SOURCE OF MIANUS RIVER WATER FOR WASHING SCREENS ON THE INTAKE FLUME. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

  4. Rotorcraft convertible engine study

    NASA Technical Reports Server (NTRS)

    Goldstein, D. N.; Hirschkron, R.; Smith, C. E.

    1983-01-01

    Convertible propulsion systems for advanced rotorcraft are evaluated in terms of their impact on aircraft operating economics and fuel consumption. A variety of propulsion system concepts, including separate thrust and power producing engines, convertible fan/shaft engines, and auxiliary propeller configurations are presented. The merits of each are evaluated in two different rotorcraft missions: an intercity, commercial transport of the ABC(TM) type, and an offshore oil ring supply ship of the X-wing type. The variable inlet guide vane fan/shaft converting engine and auxiliary propeller configurations are shown to offer significant advantages over all the other systems evaluated, in terms of both direct operating cost and fuel consumption.

  5. Vector generator scan converter

    DOEpatents

    Moore, J.M.; Leighton, J.F.

    1988-02-05

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardware for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold. 7 figs.

  6. Vector generator scan converter

    DOEpatents

    Moore, James M.; Leighton, James F.

    1990-01-01

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O (input/output) channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardward for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold.

  7. The terrestrial silica pump.

    PubMed

    Carey, Joanna C; Fulweiler, Robinson W

    2012-01-01

    Silicon (Si) cycling controls atmospheric CO(2) concentrations and thus, the global climate, through three well-recognized means: chemical weathering of mineral silicates, occlusion of carbon (C) to soil phytoliths, and the oceanic biological Si pump. In the latter, oceanic diatoms directly sequester 25.8 Gton C yr(-1), accounting for 43% of the total oceanic net primary production (NPP). However, another important link between C and Si cycling remains largely ignored, specifically the role of Si in terrestrial NPP. Here we show that 55% of terrestrial NPP (33 Gton C yr(-1)) is due to active Si-accumulating vegetation, on par with the amount of C sequestered annually via marine diatoms. Our results suggest that similar to oceanic diatoms, the biological Si cycle of land plants also controls atmospheric CO(2) levels. In addition, we provide the first estimates of Si fixed in terrestrial vegetation by major global biome type, highlighting the ecosystems of most dynamic Si fixation. Projected global land use change will convert forests to agricultural lands, increasing the fixation of Si by land plants, and the magnitude of the terrestrial Si pump. PMID:23300825

  8. The Terrestrial Silica Pump

    PubMed Central

    Carey, Joanna C.; Fulweiler, Robinson W.

    2012-01-01

    Silicon (Si) cycling controls atmospheric CO2 concentrations and thus, the global climate, through three well-recognized means: chemical weathering of mineral silicates, occlusion of carbon (C) to soil phytoliths, and the oceanic biological Si pump. In the latter, oceanic diatoms directly sequester 25.8 Gton C yr−1, accounting for 43% of the total oceanic net primary production (NPP). However, another important link between C and Si cycling remains largely ignored, specifically the role of Si in terrestrial NPP. Here we show that 55% of terrestrial NPP (33 Gton C yr−1) is due to active Si-accumulating vegetation, on par with the amount of C sequestered annually via marine diatoms. Our results suggest that similar to oceanic diatoms, the biological Si cycle of land plants also controls atmospheric CO2 levels. In addition, we provide the first estimates of Si fixed in terrestrial vegetation by major global biome type, highlighting the ecosystems of most dynamic Si fixation. Projected global land use change will convert forests to agricultural lands, increasing the fixation of Si by land plants, and the magnitude of the terrestrial Si pump. PMID:23300825

  9. Performance characteristics of proximity focused ultraviolet image converters

    NASA Technical Reports Server (NTRS)

    Williams, J. T.; Feibelman, W. A.

    1973-01-01

    Performance characteristics of Bendix type BX 8025-4522 proximity focused image tubes for UV to visible light conversion are presented. Quantum efficiency, resolution, background, geometric distortion, and environmental test results are discussed. The converters use magnesium fluoride input windows with Cs-Te photocathodes and P-11 phosphors on fiber optic output windows.

  10. Nonuniversality of entanglement convertibility

    NASA Astrophysics Data System (ADS)

    Bragança, Helena; Mascarenhas, Eduardo; Luiz, G. I.; Duarte, C.; Pereira, R. G.; Santos, M. F.; Aguiar, M. C. O.

    2014-06-01

    Recently, it has been suggested that operational properties connected to quantum computation can be alternative indicators of quantum phase transitions. In this work we systematically study these operational properties in one-dimensional systems that present phase transitions of different orders. For this purpose, we evaluate the local convertibility between bipartite ground states. Our results suggest that the operational properties, related to nonanalyticities of the entanglement spectrum, are good detectors of explicit symmetries of the model, but not necessarily of phase transitions. We also show that thermodynamically equivalent phases, such as Luttinger liquids, may display different convertibility properties depending on the underlying microscopic model.

  11. A solar thermophotovoltaic converter

    NASA Astrophysics Data System (ADS)

    Demichelis, F.; Minetti-Mezzetti, E.

    1980-08-01

    A model of a thermophotovoltaic (TPV) converter is presented. Sunlight was focused by an optical system into a spherical cavity made of tungsten or of ytterbium oxide, thereby heating the cavity. The spectral region of the incandescent radiation emitted by the cavity in the range 0.6-1.1 microns (corresponding to the maximum efficiency of silicon cells) was directed onto a distribution of cells facing the radiator. The part of the spectrum not in the range 0.6-1.1 microns was sent back to the radiator and recycled. Conversion efficiencies of about 24% are possible in a TPV converter operating with a 2000 K radiator.

  12. Well pump

    DOEpatents

    Ames, Kenneth R.; Doesburg, James M.

    1987-01-01

    A well pump includes a piston and an inlet and/or outlet valve assembly of special structure. Each is formed of a body of organic polymer, preferably PTFE. Each includes a cavity in its upper portion and at least one passage leading from the cavity to the bottom of the block. A screen covers each cavity and a valve disk covers each screen. Flexible sealing flanges extend upwardly and downwardly from the periphery of the piston block. The outlet valve block has a sliding block and sealing fit with the piston rod.

  13. Fractional Watt AMTEC Converter

    NASA Astrophysics Data System (ADS)

    Hunt, T. K.; Rasmussen, J. R.

    2006-01-01

    We report here the long term performance of a small, multi-tube AMTEC converter. This converter was designed to operate and produce approximately 12 watt of electrical output from a small, 4 to 6 watt radioisotope heat source for remote power applications. It was built and put on test in 1999 using electrical heaters as stand-ins for the radioisotope capsule. Since that time it has accumulated more than 5 years of run time at an input heater temperature of 700 °C, with numerous thermal cycles to ambient that were generally related to grid power failures or physical moves of the test apparatus. The power output has remained, with variations due to orientation changes and minor variations due to small temperature changes, essentially constant at 0.40 W to 0.60 W over the test period and operation is ongoing. The converter casing and mechanical structure was fabricated from 316 SS and the electrodes are sputtered titanium nitride films. Separate static tests of a multilayer insulation package suitable for use with the converter showed the capability to reach 700 °C with a thermal input of < 4 watts.

  14. Thermionic energy converters

    DOEpatents

    Monroe, Jr., James E.

    1977-08-09

    A thermionic device for converting nuclear energy into electrical energy comprising a tubular anode spaced from and surrounding a cylindrical cathode, the cathode having an outer emitting surface of ruthenium, and nuclear fuel on the inner cylindrical surface. The nuclear fuel is a ceramic composition of fissionable material in a metal matrix. An axial void is provided to collect and contain fission product gases.

  15. Liquid metal thermal electric converter

    DOEpatents

    Abbin, Joseph P.; Andraka, Charles E.; Lukens, Laurance L.; Moreno, James B.

    1989-01-01

    A liquid metal thermal electric converter which converts heat energy to electrical energy. The design of the liquid metal thermal electric converter incorporates a unique configuration which directs the metal fluid pressure to the outside of the tube which results in the structural loads in the tube to be compressive. A liquid metal thermal electric converter refluxing boiler with series connection of tubes and a multiple cell liquid metal thermal electric converter are also provided.

  16. Thermionic energy converters

    NASA Technical Reports Server (NTRS)

    Morris, J. F. (Inventor)

    1983-01-01

    The efficiency of thermionic energy converters is improved by internal distribution of tiny sorted cesium diodes driven by the thermal gradient between the primary emitter and the collector. The tiny, sorted diode distribution comprises protrusions of the emitter material from the main emitter face which contact the main collector face thermally but not electrically. The main collector ends of the protrusions are separated from the main collector by a thin layer of insulation, such as aluminum oxide. The shorted tiny diode distribution augments cesium ionization through internal thermal effects only within the main diode. No electrical inputs are required. This ionization enhancement by the distribution of the tiny shorted diodes not only reduces the plasma voltage drop but also increases the power output and efficiency of the overall thermionic energy converter.

  17. Digital to synchro converter

    NASA Technical Reports Server (NTRS)

    Predina, Joseph P. (Inventor)

    1989-01-01

    A digital-to-synchro converter is provided where a binary input code specifies a desired shaft angle and where an resolver type position transducer is employed with additional circuitry to generate a shaft position error signal indicative of the angular difference between the desired shaft angle and the actual shaft angle. The additional circuitry corrects for known and calculated errors in the shaft position detection process and equipment.

  18. Solar UV variability

    NASA Technical Reports Server (NTRS)

    Donnelly, Richard F.

    1989-01-01

    Measurements from the Solar Backscatter Ultraviolet (SBUV) provide solar UV flux in the 160 to 400 nm wavelength range, backed up by independent measurement in the 115 to 305 nm range from the Solar Mesosphere Explorer (SME). The full disc UV flux from spatially resolved measurements of solar activity was modeled, which provides a better understanding of why the UV variations have their observed temporal and wavelength dependencies. Long term, intermediate term, and short term variations are briefly examined.

  19. LMFBR with booster pump in pumping loop

    DOEpatents

    Rubinstein, H.J.

    1975-10-14

    A loop coolant circulation system is described for a liquid metal fast breeder reactor (LMFBR) utilizing a low head, high specific speed booster pump in the hot leg of the coolant loop with the main pump located in the cold leg of the loop, thereby providing the advantages of operating the main pump in the hot leg with the reliability of cold leg pump operation.

  20. Liquid metal pump

    DOEpatents

    Pennell, William E.

    1982-01-01

    The liquid metal pump comprises floating seal rings and attachment of the pump diffuser to the pump bowl for isolating structural deflections from the pump shaft bearings. The seal rings also eliminate precision machining on large assemblies by eliminating the need for a close tolerance fit between the mounting surfaces of the pump and the seals. The liquid metal pump also comprises a shaft support structure that is isolated from the pump housing for better preservation of alignment of shaft bearings. The shaft support structure also allows for complete removal of pump internals for inspection and repair.

  1. Winding for linear pump

    DOEpatents

    Kliman, Gerald B.; Brynsvold, Glen V.; Jahns, Thomas M.

    1989-01-01

    A winding and method of winding for a submersible linear pump for pumping liquid sodium is disclosed. The pump includes a stator having a central cylindrical duct preferably vertically aligned. The central vertical duct is surrounded by a system of coils in slots. These slots are interleaved with magnetic flux conducting elements, these magnetic flux conducting elements forming a continuous magnetic field conduction path along the stator. The central duct has placed therein a cylindrical magnetic conducting core, this core having a cylindrical diameter less than the diameter of the cylindrical duct. The core once placed to the duct defines a cylindrical interstitial pumping volume of the pump. This cylindrical interstitial pumping volume preferably defines an inlet at the bottom of the pump, and an outlet at the top of the pump. Pump operation occurs by static windings in the outer stator sequentially conveying toroidal fields from the pump inlet at the bottom of the pump to the pump outlet at the top of the pump. The winding apparatus and method of winding disclosed uses multiple slots per pole per phase with parallel winding legs on each phase equal to or less than the number of slots per pole per phase. The slot sequence per pole per phase is chosen to equalize the variations in flux density of the pump sodium as it passes into the pump at the pump inlet with little or no flux and acquires magnetic flux in passage through the pump to the pump outlet.

  2. Winding for linear pump

    DOEpatents

    Kliman, G.B.; Brynsvold, G.V.; Jahns, T.M.

    1989-08-22

    A winding and method of winding for a submersible linear pump for pumping liquid sodium are disclosed. The pump includes a stator having a central cylindrical duct preferably vertically aligned. The central vertical duct is surrounded by a system of coils in slots. These slots are interleaved with magnetic flux conducting elements, these magnetic flux conducting elements forming a continuous magnetic field conduction path along the stator. The central duct has placed therein a cylindrical magnetic conducting core, this core having a cylindrical diameter less than the diameter of the cylindrical duct. The core once placed to the duct defines a cylindrical interstitial pumping volume of the pump. This cylindrical interstitial pumping volume preferably defines an inlet at the bottom of the pump, and an outlet at the top of the pump. Pump operation occurs by static windings in the outer stator sequentially conveying toroidal fields from the pump inlet at the bottom of the pump to the pump outlet at the top of the pump. The winding apparatus and method of winding disclosed uses multiple slots per pole per phase with parallel winding legs on each phase equal to or less than the number of slots per pole per phase. The slot sequence per pole per phase is chosen to equalize the variations in flux density of the pump sodium as it passes into the pump at the pump inlet with little or no flux and acquires magnetic flux in passage through the pump to the pump outlet. 4 figs.

  3. Transistorized converter provides nondissipative regulation

    NASA Technical Reports Server (NTRS)

    1964-01-01

    A transistorized regulator converter efficiently converts fluctuating input voltages to a constant output voltage, avoiding the use of saturable reactors. It is nondissipative in operation and functions in an open loop through variable duty cycles.

  4. Electrothermodynamic (etd) power converter

    SciTech Connect

    Marks, A.M.

    1983-07-26

    These inventions relate to novel advances in Electrothermodynamics (ETD), also known as charged aerosol, heat/electric power generators: (1) A new more efficient, compact converging/diverging configuration comprising a torus of revolution (TORON) used with a gas flywheel. (2) A ''Method II'' two-fluid mixed flow ejector/converter in a gas flywheel loop employing a primary steam or a high molecular weight driver jet such as a fluorocarbon containing charged aerosol water droplets and a low molecular weight carrier gas such as hydrogen or helium with an electro-negative gas additive, in a Rankine cycle including a vapor/gas and liquid separator with a bypass to the ejector/converter loop. (3) A ''Method III'' two-fluid mixed flow comprising a supersonic jet expanding conically within a subsonic flow, separated by a boundary layer in which the charged aerosol forms downstream of the orifice, at a cross section of at least 100 times the orifice section; and in which the electric charge density of the charged aerosol decreases along the jet axis, whereby substantially all of the kinetic power of the jet is converted to electric power within the jet, there being no ejector. (4) An array of supersonic jets utilizing Method III. (5) An array of supersonic jets utilizing Method III without separating duct walls in which ''convection cells'' provide return flows, forming a plurality of TORON configurations. (6) A supercritical Rankline cycle in a single stage employing Method III. (7) A method IV two-fluid cycle uses charged aerosols in an inert gas and operates on an Ericsson-type cycle. (8) Optimum operating conditions are defined for Methods II, III, and IV. (9) A high potential emitter is employed with a grounded body, and a sapphire tube sealed to metal by a new technique provides an insulating duct for the high temperature, high pressure vapor.

  5. Modelling UV sky for future UV missions

    NASA Astrophysics Data System (ADS)

    Sreejith, A. G.; Safanova, M.; Mohan, R.; Murthy, Jayant

    Software simulators are now widely used in all areas of science, especially in application to astronomical missions: from instrument design to mission planning, and to data interpretation. We present a simulator to model the diffuse ultraviolet sky, where the different contributors are separately calculated and added together to produce a sky image of the size specified by the instrument requirements. Each of the contributors to the background, instrumental dark current, airglow, zodiacal light and diffuse galactic light, is dependent on various factors. Airglow is dependent on the time of day, zodiacal light on the time of year, angle from the Sun and from the ecliptic, and diffuse UV emission depends on the look direction. To provide a full description of any line of sight, we have also added stars. The diffuse UV background light can dominate in many areas of the sky and severely impact space telescopes viewing directions due to over brightness. The simulator, available as a downloadable package and as a simple web-based tool, can be applied to separate missions and instruments. For demonstration, we present the example used for two UV missions: the UVIT instrument on the Indian ASTROSAT mission to be launched in the next year and a prospective wide-field mission to search for transients in the UV.

  6. Cycloidal Wave Energy Converter

    SciTech Connect

    Stefan G. Siegel, Ph.D.

    2012-11-30

    This program allowed further advancing the development of a novel type of wave energy converter, a Cycloidal Wave Energy Converter or CycWEC. A CycWEC consists of one or more hydrofoils rotating around a central shaft, and operates fully submerged beneath the water surface. It operates under feedback control sensing the incoming waves, and converts wave power to shaft power directly without any intermediate power take off system. Previous research consisting of numerical simulations and two dimensional small 1:300 scale wave flume experiments had indicated wave cancellation efficiencies beyond 95%. The present work was centered on construction and testing of a 1:10 scale model and conducting two testing campaigns in a three dimensional wave basin. These experiments allowed for the first time for direct measurement of electrical power generated as well as the interaction of the CycWEC in a three dimensional environment. The Atargis team successfully conducted two testing campaigns at the Texas A&M Offshore Technology Research Center and was able to demonstrate electricity generation. In addition, three dimensional wave diffraction results show the ability to achieve wave focusing, thus increasing the amount of wave power that can be extracted beyond what was expected from earlier two dimensional investigations. Numerical results showed wave cancellation efficiencies for irregular waves to be on par with results for regular waves over a wide range of wave lengths. Using the results from previous simulations and experiments a full scale prototype was designed and its performance in a North Atlantic wave climate of average 30kW/m of wave crest was estimated. A full scale WEC with a blade span of 150m will deliver a design power of 5MW at an estimated levelized cost of energy (LCOE) in the range of 10-17 US cents per kWh. Based on the new results achieved in the 1:10 scale experiments these estimates appear conservative and the likely performance at full scale will

  7. WSO-UV project

    NASA Astrophysics Data System (ADS)

    Sachkov, Mikhail; Shustov, Boris; Gómez de Castro, Ana Ines

    2014-03-01

    During last three decades, astronomers have enjoyed continuous access to the 100-300 nm ultraviolet (UV) spectral range where the resonance transitions of the most abundant atoms and ions (at temperatures between 3000 and 300 000 K) reside. This UV range is not accessible from ground-based facilities. The successful International Ultraviolet Explorer (IUE) observatory, the Russian ASTRON mission and successor instruments such as the Galaxy Evolution Explorer (GALEX) mission or the COS and STIS spectrographs on-board the Hubble Space Telescope (HST) prove the major impact of observations in the UV wavelength range in modern astronomy. Future access to space-based observatories is expected to be very limited. For the next decade, the post-HST era, the World Space Observatory - Ultraviolet (WSO-UV) will be the only 2-m class UV telescope with capabilities similar to the HST. WSO-UV will be equipped with instruments for imaging and spectroscopy and it will be a facility dedicated, full-time, to UV astronomy. In this article, we briefly outline the current status of the WSO-UV mission and the science management plan.

  8. [Erythemogenic UV rays].

    PubMed

    Sigurgeirsson, Bardur; Wulf, Hans Christian

    2011-07-01

    The UV-index is an international standard measurement of the strength of erythemogenic ultraviolet radiation. It is often published in the media and then refers to the highest expected UV radiation for that day. The highest UV-index value measured in Iceland is seven. Although this is similar to the maximum values from southern Scandinavia, the average UV-index is lower in Iceland compared to other Nordic countries. Around solar noon the UV index is roughly equivalent to the Standard Erythema Dose (SED). During a bright summer day in Iceland the number of Standard Erythema doses can go as high as 32, but is on average in June around twenty. The typical Icelander gets red after 4-6 SED and it is obvious that during solar noon it is easy to sunburn in Iceland if you stay outside without sun protection. PMID:21849709

  9. Bidirectional pumped high power Raman fiber laser.

    PubMed

    Xiao, Q; Yan, P; Li, D; Sun, J; Wang, X; Huang, Y; Gong, M

    2016-03-21

    This paper presents a 3.89 kW 1123 nm Raman all-fiber laser with an overall optical-to-optical efficiency of 70.9%. The system consists of a single-wavelength (1070nm) seed and one-stage bidirectional 976 nm non-wavelength-stabilized laser diodes (LDs) pumped Yb-doped fiber amplifier. The unique part of this system is the application of non-wavelength-stabilized LDs in high power bidirectional pumping configuration fiber amplifier via refractive index valley fiber combiners. This approach not only increases the pump power, but also shortens the length of fiber by avoiding the usage of multi-stage amplifier. Through both theoretical research and experiment, the bidirectional pumping configuration presented in this paper proves to be able to convert 976 nm pump laser to 1070 nm laser via Yb3+ transfer, which is then converted into 1123 nm Raman laser via the first-order Raman effect without the appearance of any higher-order Raman laser. PMID:27136862

  10. Gallium phosphide energy converters

    NASA Technical Reports Server (NTRS)

    Sims, P. E.; Dinetta, L. C.; Goetz, M. A.

    1995-01-01

    Gallium phosphide (GaP) energy converters may be successfully deployed to provide new mission capabilities for spacecraft. Betavoltaic power supplies based on the conversion of tritium beta decay to electricity using GaP energy converters can supply long term low-level power with high reliability. High temperature solar cells, also based on GaP, can be used in inward-bound missions greatly reducing the need for thermal dissipation. Results are presented for GaP direct conversion devices powered by Ni-63 and compared to the conversion of light emitted by tritiarated phosphors. Leakage currents as low as 1.2 x 10(exp -17) A/sq cm have been measured and the temperature dependence of the reverse saturation current is found to have ideal behavior. Temperature dependent IV, QE, R(sub sh), and V(sub oc) results are also presented. These data are used to predict the high-temperature solar cell and betacell performance of GaP devices and suggest appropriate applications for the deployment of this technology.

  11. Bidirectional buck boost converter

    DOEpatents

    Esser, Albert Andreas Maria

    1998-03-31

    A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero.

  12. Bidirectional buck boost converter

    DOEpatents

    Esser, A.A.M.

    1998-03-31

    A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero. 20 figs.

  13. UV-LED exposure system for low-cost photolithography

    NASA Astrophysics Data System (ADS)

    Yapici, Murat Kaya; Farhat, Ilyas

    2014-03-01

    This paper reports the development of a low-cost, portable, light-emitting diode (LED)-based UV exposure system for photolithography. The major system components include UV-LEDs, microcontroller, digital-to-analog (D/A) converter and LED control circuitry. The UV-LED lithography system is also equipped with a digital user interface (LCD and keypad) and permits accurate electronic control on the exposure time and power. Hence the exposure dose can be varied depending on process requirements. Compared to traditional contact lithography, the UV-LED lithography system is significantly cheaper, simple to construct using off-the shelf components and does not require complex infrastructure to operate. Such reduction in system cost and complexity renders UV-LED lithography as a perfect candidate for micro lithography with large process windows typically suitable for MEMS, microfluidics applications.

  14. Multiple pump housing

    DOEpatents

    Donoho, II, Michael R.; Elliott; Christopher M.

    2010-03-23

    A fluid delivery system includes a first pump having a first drive assembly, a second pump having a second drive assembly, and a pump housing. At least a portion of each of the first and second pumps are located in the housing.

  15. Supreme EnLIGHTenment: Damage Recognition and Signaling in the Mammalian UV Response

    PubMed Central

    Herrlich, Peter; Karin, Michael; Weiss, Carsten

    2009-01-01

    Like their prokaryotic counterparts, mammalian cells can sense light, especially in the ultraviolet (UV) range of the spectrum. Following UV exposure cells mount an elaborate response – called the UV response, which mimics physiological signaling responses except that it targets multiple pathways thereby lacking the defined specificity of receptor-triggered signal transduction. Despite many years of research it is still not fully clear how UV radiation is sensed and converted into the „language of cells“ - signal reception and transduction. This review focuses on how photonic energy and its primary cellular products are sensed to elicit the UV response. PMID:18280234

  16. UV, stress and aging.

    PubMed

    Debacq-Chainiaux, Florence; Leduc, Cedric; Verbeke, Alix; Toussaint, Olivier

    2012-07-01

    Skin is a model of choice in studies on aging. Indeed, skin aging can be modulated by internal and external factors, reflecting its complexity. Two types of skin aging have been identified: intrinsic, mainly genetically determined and extrinsic-also called "photo-aging"-resulting on the impact of environmental stress and more precisely of UV rays. Simplified in vitro models, based on cellular senescence, have been developed to study the relationship between UV and aging. These models vary on the cell type (fibroblasts or keratinocytes, normal or immortalized) and the type of UV used (UVA or UVB). PMID:23467762

  17. Unity power factor converter

    NASA Technical Reports Server (NTRS)

    Wester, Gene W. (Inventor)

    1980-01-01

    A unity power factor converter capable of effecting either inversion (dc-to-dc) or rectification (ac-to-dc), and capable of providing bilateral power control from a DC source (or load) through an AC transmission line to a DC load (or source) for power flow in either direction, is comprised of comparators for comparing the AC current i with an AC signal i.sub.ref (or its phase inversion) derived from the AC ports to generate control signals to operate a switch control circuit for high speed switching to shape the AC current waveform to a sine waveform, and synchronize it in phase and frequency with the AC voltage at the AC ports, by selectively switching the connections to a series inductor as required to increase or decrease the current i.

  18. Electromagnetic wave energy converter

    NASA Technical Reports Server (NTRS)

    Bailey, R. L. (Inventor)

    1973-01-01

    Electromagnetic wave energy is converted into electric power with an array of mutually insulated electromagnetic wave absorber elements each responsive to an electric field component of the wave as it impinges thereon. Each element includes a portion tapered in the direction of wave propagation to provide a relatively wideband response spectrum. Each element includes an output for deriving a voltage replica of the electric field variations intercepted by it. Adjacent elements are positioned relative to each other so that an electric field subsists between adjacent elements in response to the impinging wave. The electric field results in a voltage difference between adjacent elements that is fed to a rectifier to derive dc output power.

  19. Fluorescent radiation converter

    NASA Technical Reports Server (NTRS)

    Viehmann, W. (Inventor)

    1981-01-01

    A fluorescence radiation converter is described which includes a substantially undoped optically transparent substrate and a waveshifter coating deposited on at least one portion of the substrate for absorption of radiation and conversion of fluorescent radiation. The coating is formed to substantially 1000 g/liter of a solvent, 70 to 200 g/liter of an organic polymer, and 0.2 to 25 g/liter of at least one organic fluorescent dye. The incoming incident radiation impinges on the coating. Radiation is absorbed by the fluorescent dye and is re-emitted as a longer wavelength radiation. Radiation is trapped within the substrate and is totally internally reflected by the boundary surface. Emitted radiation leaves the substrate ends to be detected.

  20. Subpicosecond high-brightness uv laser system

    SciTech Connect

    Gibson, R.B.

    1986-01-01

    A laser system that produces intense subpicosecond pulses of 248 nm light is under development. Ultrashort pulses are generated in the visible in a synchronously-pumped mode-locked dye oscillator, heterodyned into the uv by two KDP crystals, and amplified in a chain of KrF* amplifiers. Front end output of 5 ..mu..J is amplified to 20 mJ and focused to peak intensities of order 10/sup 17/ W cm/sup -2/. Additional amplification is expected to permit experiments at intensities >10/sup 20/ W cm/sup -2/.

  1. Continuously pumping and reactivating gas pump

    DOEpatents

    Batzer, T.H.; Call, W.R.

    Apparatus for continuous pumping using cycling cryopumping panels. A plurality of liquid helium cooled panels are surrounded by movable nitrogen cooled panels that alternatively expose or shield the helium cooled panels from the space being pumped. Gases condense on exposed helium cooled panels until the nitrogen cooled panels are positioned to isolate the helium cooled panels. The helium cooled panels are incrementally warmed, causing captured gases to accumulate at the base of the panels, where an independant pump removes the gases. After the helium cooled panels are substantially cleaned of condensate, the nitrogen cooled panels are positioned to expose the helium cooled panels to the space being pumped.

  2. Continuously pumping and reactivating gas pump

    DOEpatents

    Batzer, Thomas H.; Call, Wayne R.

    1984-01-01

    Apparatus for continuous pumping using cycling cyropumping panels. A plurality of liquid helium cooled panels are surrounded by movable nitrogen cooled panels the alternatively expose or shield the helium cooled panels from the space being pumped. Gases condense on exposed helium cooled panels until the nitrogen cooled panels are positioned to isolate the helium cooled panels. The helium cooled panels are incrementally warmed, causing captured gases to accumulate at the base of the panels, where an independent pump removes the gases. After the helium cooled panels are substantially cleaned of condensate, the nitrogen cooled panels are positioned to expose the helium cooled panels to the space being pumped.

  3. UV Completion of Axion

    SciTech Connect

    Choi, Kang-Sin

    2008-11-23

    A multiple number of global U(1)s, arising from accidental symmetries up to a certain order of the potential, enjoy lowering the axion decay constant from UV-scale and evading supersymmetric Fayet-Illiopoulos term constraints.

  4. Gastrostomy feeding tube - pump - child

    MedlinePlus

    Feeding - gastrostomy tube - pump; G-tube - pump; Gastrostomy button - pump; Bard Button - pump; MIC-KEY - pump ... Gather supplies: Feeding pump (electronic or battery powered) Feeding set that matches the feeding pump (includes a feeding bag, drip chamber, roller clamp, ...

  5. UV Signature Mutations †

    PubMed Central

    2014-01-01

    Sequencing complete tumor genomes and exomes has sparked the cancer field's interest in mutation signatures for identifying the tumor's carcinogen. This review and meta-analysis discusses signatures and their proper use. We first distinguish between a mutagen's canonical mutations – deviations from a random distribution of base changes to create a pattern typical of that mutagen – and the subset of signature mutations, which are unique to that mutagen and permit inference backward from mutations to mutagen. To verify UV signature mutations, we assembled literature datasets on cells exposed to UVC, UVB, UVA, or solar simulator light (SSL) and tested canonical UV mutation features as criteria for clustering datasets. A confirmed UV signature was: ≥60% of mutations are C→T at a dipyrimidine site, with ≥5% CC→TT. Other canonical features such as a bias for mutations on the non-transcribed strand or at the 3' pyrimidine had limited application. The most robust classifier combined these features with criteria for the rarity of non-UV canonical mutations. In addition, several signatures proposed for specific UV wavelengths were limited to specific genes or species; non-signature mutations induced by UV may cause melanoma BRAF mutations; and the mutagen for sunlight-related skin neoplasms may vary between continents. PMID:25354245

  6. UV signature mutations.

    PubMed

    Brash, Douglas E

    2015-01-01

    Sequencing complete tumor genomes and exomes has sparked the cancer field's interest in mutation signatures for identifying the tumor's carcinogen. This review and meta-analysis discusses signatures and their proper use. We first distinguish between a mutagen's canonical mutations—deviations from a random distribution of base changes to create a pattern typical of that mutagen—and the subset of signature mutations, which are unique to that mutagen and permit inference backward from mutations to mutagen. To verify UV signature mutations, we assembled literature datasets on cells exposed to UVC, UVB, UVA, or solar simulator light (SSL) and tested canonical UV mutation features as criteria for clustering datasets. A confirmed UV signature was: ≥60% of mutations are C→T at a dipyrimidine site, with ≥5% CC→TT. Other canonical features such as a bias for mutations on the nontranscribed strand or at the 3' pyrimidine had limited application. The most robust classifier combined these features with criteria for the rarity of non-UV canonical mutations. In addition, several signatures proposed for specific UV wavelengths were limited to specific genes or species; UV's nonsignature mutations may cause melanoma BRAF mutations; and the mutagen for sunlight-related skin neoplasms may vary between continents. PMID:25354245

  7. Turbo-Brayton Power Converter

    NASA Technical Reports Server (NTRS)

    Breedlove, Jeffrey

    2015-01-01

    Future NASA space missions will require advanced thermal-to-electric power converters that are reliable, efficient, and lightweight. Creare, LLC, is developing a turbo-Brayton power converter that offers high efficiency and specific power. The converter employs gas bearings to provide maintenance free, long-life operation. Discrete components can be packaged to fit optimally with other subsystems, and the converter's continuous gas flow can communicate directly with remote heat sources and heat rejection surfaces without the need for ancillary heat-transfer components and intermediate flow loops. Creare has completed detailed analyses, trade studies, fabrication trials, and preliminary designs for the components and converter assembly. The company is fabricating and testing a breadboard converter.

  8. Pulsed thermionic converter study

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A nuclear electric propulsion concept using a thermionic reactor inductively coupled to a magnetoplasmadynamic accelerator (MPD arc jet) is described, and the results of preliminary analyses are presented. In this system, the MPD thruster operates intermittently at higher voltages and power levels than the thermionic generating unit. A typical thrust pulse from the MPD arc jet is characterized by power levels of 1 to 4 MWe, a duration of 1 msec, and a duty cycle of approximately 20%. The thermionic generating unit operates continuously but with a lower power level of approximately 0.4 MWe. Energy storage between thrust pulses is provided by building up a large current in an inductor using the output of the thermionic converter array. Periodically, the charging current is interrupted, and the energy stored in the magnetic field of the inductor is utilized for a short duration thrust pulse. The results of the preliminary analysis show that a coupling effectiveness of approximately 85 to 90% is feasible for a nominal 400 KWe system with an inductive unit suitable for a flight vehicle.

  9. Self-powered microthermionic converter

    SciTech Connect

    Marshall, Albert C.; King, Donald B.; Zavadil, Kevin R.; Kravitz, Stanley H.; Tigges, Chris P.; Vawter, Gregory A.

    2004-08-10

    A self-powered microthermionic converter having an internal thermal power source integrated into the microthermionic converter. These converters can have high energy-conversion efficiencies over a range of operating temperatures. Microengineering techniques are used to manufacture the converter. The utilization of an internal thermal power source increases potential for mobility and incorporation into small devices. High energy efficiency is obtained by utilization of micron-scale interelectrode gap spacing. Alpha-particle emitting radioisotopes can be used for the internal thermal power source, such as curium and polonium isotopes.

  10. Gas pump with movable gas pumping panels

    DOEpatents

    Osher, J.L.

    Apparatus for pumping gas continuously a plurality of articulated panels of getter material, each of which absorbs gases on one side while another of its sides is simultaneously reactivated in a zone isolated by the panels themselves from a working space being pumped.

  11. Gas pump with movable gas pumping panels

    DOEpatents

    Osher, John E.

    1984-01-01

    Apparatus for pumping gas continuously a plurality of articulated panels of getter material, each of which absorbs gases on one side while another of its sides is simultaneously reactivated in a zone isolated by the panels themselves from a working space being pumped.

  12. Highly sensitive vacuum ion pump current measurement system

    DOEpatents

    Hansknecht, John Christopher

    2006-02-21

    A vacuum system comprising: 1) an ion pump; 2) power supply; 3) a high voltage DC--DC converter drawing power from the power supply and powering the vacuum pump; 4) a feedback network comprising an ammeter circuit including an operational amplifier and a series of relay controlled scaling resistors of different resistance for detecting circuit feedback; 5) an optional power block section intermediate the power supply and the high voltage DC--DC converter; and 6) a microprocessor receiving feedback information from the feedback network, controlling which of the scaling resistors should be in the circuit and manipulating data from the feedback network to provide accurate vacuum measurement to an operator.

  13. Insulin pump (image)

    MedlinePlus

    The catheter at the end of the insulin pump is inserted through a needle into the abdominal ... with diabetes. Dosage instructions are entered into the pump's small computer and the appropriate amount of insulin ...

  14. Proton pump inhibitors

    MedlinePlus

    Proton pump inhibitors (PPIs) are medicines that work by reducing the amount of stomach acid made by glands in ... Proton pump inhibitors are used to: Relieve symptoms of acid reflux, or gastroesophageal reflux disease (GERD). This is a ...

  15. Sizing pumps for slurries

    SciTech Connect

    Akhtar, S.Z.

    1996-11-01

    Slurry characteristics have a significant impact on centrifugal pump performance. For instance, as particle size increases or the percent solids concentration increases, pump head and efficiency decrease. Therefore, before a slurry pump is selected, it is important to define the slurry characteristics as accurately as possible. The effect of the slurry characteristics on the head and efficiency of the centrifugal pump will be emphasized (the effect on flowrate is less significant). The effect of slurry characteristics is more predominant in smaller pumps (with smaller diameter impellers) than in larger pumps. The data and relationship between the various slurry parameters have been developed from correlations and nomographs published by pump vendors from their field data and test results. The information helps to avoid specifying an undersized pump/motor assembly for slurry service.

  16. Liquid metal enabled pump

    PubMed Central

    Tang, Shi-Yang; Khoshmanesh, Khashayar; Sivan, Vijay; Petersen, Phred; O’Mullane, Anthony P.; Abbott, Derek; Mitchell, Arnan; Kalantar-zadeh, Kourosh

    2014-01-01

    Small-scale pumps will be the heartbeat of many future micro/nanoscale platforms. However, the integration of small-scale pumps is presently hampered by limited flow rate with respect to the input power, and their rather complicated fabrication processes. These issues arise as many conventional pumping effects require intricate moving elements. Here, we demonstrate a system that we call the liquid metal enabled pump, for driving a range of liquids without mechanical moving parts, upon the application of modest electric field. This pump incorporates a droplet of liquid metal, which induces liquid flow at high flow rates, yet with exceptionally low power consumption by electrowetting/deelectrowetting at the metal surface. We present theory explaining this pumping mechanism and show that the operation is fundamentally different from other existing pumps. The presented liquid metal enabled pump is both efficient and simple, and thus has the potential to fundamentally advance the field of microfluidics. PMID:24550485

  17. Ultraviolet converter transients induced by electrons

    NASA Technical Reports Server (NTRS)

    Kernell, R. L.; Becher, J.; Reft, C. S.

    1984-01-01

    The output of ultraviolet converters typically used in satellite astronomy was monitored during irradiation with electrons from a sealed SR-90 source which approximated the peak flux in earth's outer electron belt. The signal induced by irradiation was attributed to two mechanisms: (1) photoelectrons resulting from photons created in the MgF2 window and (2) the direct impact of electrons on the phosphor. For irradiation at about 1 x 10 to the 7th e/sq cm sec, these two effects produced signals which were, in order of magnitude, the same as those produced by an incident UV flux (254 nm) of 10 to the 8th and 10 to the 7th photons/sq cm sec, respectively. In addition, the induced signal was investigated as a function of electron energy by irradiating another converter with 0.4-1.8-MeV electrons from a Van de Graaff. These results suggest that the dominant contribution to the electron-induced signal is Cerenkov photon production in the MgF2 window.

  18. Photovoltaic pump systems

    NASA Astrophysics Data System (ADS)

    Klockgether, J.; Kiessling, K. P.

    1983-09-01

    Solar pump systems for the irrigation of fields and for water supply in regions with much sunshine are discussed. For surface water and sources with a hoisting depth of 12 m, a system with immersion pumps is used. For deep sources with larger hoisting depths, an underwater motor pump was developed. Both types of pump system meet the requirements of simple installation and manipulation, safe operation, maintenance free, and high efficiency reducing the number of solar cells needed.

  19. Types of Breast Pumps

    MedlinePlus

    ... uses batteries or a cord plugged into an electrical outlet to power a small motorized pump that creates suction to ... pumping. Because these breast pumps rely on a power source, women who use ... situations when electricity or extra batteries may not be available. If ...

  20. Rotary magnetic heat pump

    DOEpatents

    Kirol, Lance D.

    1988-01-01

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation.

  1. Green pumped Alexandrite lasers

    NASA Astrophysics Data System (ADS)

    Kuper, Jerry W.; Brown, David C.

    2005-04-01

    Initial experiments with pulsed and CW pumping an alexandrite laser rod at 532 nm are presented. This pumping architecture holds promise for the production of scalable diode-pumped, tunable alexandrite laser systems operating in the near infrared (750 nm), and the ultraviolet (375 and 250 nm) spectral regions.

  2. Intravenous smart pumps.

    PubMed

    Harding, Andrew D

    2013-01-01

    Intravenous (IV) smart pumps provide substantial safety features during infusion. However, nurses need to understand the requisite education necessary to fully benefit from and improve IV smart pump use and clinical integration. Failure to use IV smart pumps places the nurse and patient at increased risk. PMID:23558918

  3. Multiwell pumping device

    SciTech Connect

    Dysarz, E.D.

    1987-06-30

    This patent describes a balanced pumping apparatus for pumping two laterally spaced wells comprising: a left conductor on a left well; a right conductor on a right the well; a left pump casing inside the well conductor; a right pump casing inside the right well conductor; a left sucker rod inside the left pump casing; a right sucker rod inside the right pump casing; flexible linkage means for attachment to the top ends of the right sucker rod and left sucker rod; a drive motor with a rotating shaft; a drive sprocket rotatably engaging the flexible linkage means; a separate pump casing flange attached to the upper section of each well conductors; a separate upper flange attached to the upper section of each pump casing and positioned at an axial location above the point attached to the pump casing; a separate transition piece attached to the top of each pump casing flange; a separate pump support attached to the top of each transition piece; a plate-like structural support means placed in a vertical plane above the well conductors and supporting the drive motor, the drive sprocket, the flexible linkage means, and the sucker rods; a structural load transfer means connecting the plate-like structural support means to the well conductors; a motor control unit for supporting itself and controlling the drive motor; and a separate shaft extending across each pump support.

  4. Rotary magnetic heat pump

    DOEpatents

    Kirol, L.D.

    1987-02-11

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation. 5 figs.

  5. Pump for Saturated Liquids

    NASA Technical Reports Server (NTRS)

    Elliott, D. G.

    1986-01-01

    Boiling liquids pumped by device based on proven components. Expanding saturated liquid in nozzle and diverting its phases along separate paths in liquid/vapor separator raises pressure of liquid. Liquid cooled in process. Pump makes it unnecessary to pressurize cryogenic liquids in order to pump them. Problems of introducing noncondensable pressurizing gas avoided.

  6. Proposed electromagnetic wave energy converter

    NASA Technical Reports Server (NTRS)

    Bailey, R. L.

    1973-01-01

    Device converts wave energy into electric power through array of insulated absorber elements responsive to field of impinging electromagnetic radiation. Device could also serve as solar energy converter that is potentially less expensive and fragile than solar cells, yet substantially more efficient.

  7. Thyristor converter simulation and analysis

    SciTech Connect

    Zhang, S.Y.

    1991-01-01

    In this paper we present a simulation on thyristor converters. The simulation features nonlinearity, non-uniform firing, and the commutations. Several applications such as a current regulation, a converter frequency characteristics analysis, and a power line disturbance analysis will be presented. 4 refs., 4 figs.

  8. UV actinometer film

    NASA Technical Reports Server (NTRS)

    Coulbert, C. D.; Gupta, A.; Pitts, J.

    1980-01-01

    Cumulative UV radiation can be measured by low-cost polymer film that is unaffacted by visible light. Useful for virtually any surface, film can help paint and plastics manufacturers determine how well their products stand up against UV radiation. Actinometer film uses photochemically sensitive compound that changes its chemical composition in response to solar radiation. Extent of chemical conversion depends on length exposure and can be measured by examining film sample with spectrophotometer. Film can be exposed from several seconds up to month.

  9. Thermal lensing and laser operation of flashlamp-pumped Cr:GSAG

    NASA Astrophysics Data System (ADS)

    Struve, B.; Fuhrberg, P.; Luhs, W.; Litfin, G.

    1988-02-01

    We analysed the thermal lensing of Cr:GSAG laser rods and developed optimized resonator and pump configurations for singleshot excitation. Efficient blocking of the UV part of the pump light spectrum allows stable laser operation in free-running, tunable, and Q-switched operation.

  10. Liquid metal electric pump

    DOEpatents

    Abbin, Joseph P.; Andraka, Charles E.; Lukens, Laurance L.; Moreno, James B.

    1992-01-01

    An electrical pump for pumping liquid metals to high pressures in high temperature environments without the use of magnets or moving mechanical parts. The pump employs a non-porous solid electrolyte membrane, typically ceramic, specific to the liquid metal to be pumped. A DC voltage is applied across the thickness of the membrane causing ions to form and enter the membrane on the electrically positive surface, with the ions being neutralized on the opposite surface. This action provides pumping of the liquid metal from one side of the non-porous solid electrolyte membrane to the other.

  11. Jet pump assisted artery

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A procedure for priming an arterial heat pump is reported; the procedure also has a means for maintaining the pump in a primed state. This concept utilizes a capillary driven jet pump to create the necessary suction to fill the artery. Basically, the jet pump consists of a venturi or nozzle-diffuser type constriction in the vapor passage. The throat of this venturi is connected to the artery. Thus vapor, gas, liquid, or a combination of the above is pumped continuously out of the artery. As a result, the artery is always filled with liquid and an adequate supply of working fluid is provided to the evaporator of the heat pipe.

  12. Degassing a vacuum system with in-situ UV radiation

    SciTech Connect

    Koebley, Sean R.; Outlaw, Ronald A.; Dellwo, Randy R.

    2012-11-15

    Photon-stimulated desorption (PSD) from a high-powered ultraviolet source was investigated as a technique to degas a vacuum system. A stainless steel vacuum system was pumped down from atmosphere with different time doses of 185 nm light, and the resulting outgassing rates were compared to that of a control pumpdown without UV assistance. PSD was found to provide a factor of 2 advantage in pumpdown pressure after only 30 min of UV exposure, with no additional advantage observed for longer irradiation times. Specifically, an outgassing rate of 3 Multiplication-Sign 10{sup -10} Torr L s{sup -1} cm{sup -2} was reached 3 h sooner in pumpdowns with UV assistance compared to those without UV, while a rate of 1.2 Multiplication-Sign 10{sup -10} Torr L s{sup -1} cm{sup -2} was reached 16 h sooner in UV runs. The authors calculated that about 22 monolayers of water were desorbed after 30 min of UV exposure. The results indicate that PSD by a 40 W 185 nm UV source can serve as a nonthermal technique to significantly speed the pumpdown of a vacuum system from atmosphere after only 30 min.

  13. IR-UV photochemistry of protein-nucleic acid systems

    SciTech Connect

    Kozub, J.; Edwards, G.

    1995-12-31

    UV light has often been used to induce the formation of covalent bonds between DNA (or RNA) and tightly-bound protein molecules. However, the internal photoreactions of nucleic acids and proteins limit the yield and complicate the analysis of intermolecular crosslinks. In an ongoing search for improved reaction specificity or new photoreactions in these systems, we have employed UV photons from a Nd:YAG-pumped dye laser and mid-IR photons from the Vanderbilt FEL. Having crosslinked several protein-nucleic acid systems with nanosecond UV laser pulses, we are currently studying the effect of various IR wavelengths on a model system (gene 32 protein and poly[dT]). We have found that irradiation with sufficiently intense FEL macropulses creates an altered form of gene 32 protein which was not observed with UV-only irradiation. The electrophoretic nobility of the product is consistent with the formation of a specific protein-protein crosslink. No evidence of the non-specific protein damage typically induced by UV light is found. The yield of the new photoproduct is apparently enhanced by exposure to FEL macropulses which are synchronized with UV laser pulses. With ideal exposure parameters, the two-color reaction effectively competes with UV-only reactions. Experiments designed to determine the reaction mechanism and to demonstrate FEL-induced reactions in other protein-nucleic acid systems are currently underway.

  14. General ignition requirements in TMR's with drift pumping

    SciTech Connect

    Logan, B.G.

    1983-01-01

    Drift pumping of collisionally trapped DT ions and thermal alpha ash in the transitions and thermal barriers of TMR plugs can be shown by simple models to dominate the central cell energy losses, requiring in fact more radial ion loss by drift pumping than axial ion loss through the potential plugs, and setting a minimum central cell length for ignition. Induced electron transport due to drift pumping is shown to be small, so grids are not needed on the direct converter to separate ion and electron currents.

  15. UV-Enhanced IR Raman System for Identifying Biohazards

    NASA Technical Reports Server (NTRS)

    Stirbl, Robert; Moynihan, Philip; Lane, Arthur

    2003-01-01

    An instrumentation system that would include an ultraviolet (UV) laser or light-emitting diode, an infrared (IR) laser, and the equivalent of an IR Raman spectrometer has been proposed to enable noncontact identification of hazardous biological agents and chemicals. In prior research, IR Raman scattering had shown promise as a means of such identification, except that the Raman-scattered light was often found to be too weak to be detected or to enable unambiguous identification in practical applications. The proposed system would utilize UV illumination as part of a two-level optical-pumping scheme to intensify the Raman signal sufficiently to enable positive identification.

  16. A novel self-assembling peptide with UV-responsive properties.

    PubMed

    Wei, Ran; Jin, Cheng-Cheng; Quan, Jing; Nie, Hua-li; Zhu, Li-Min

    2014-03-01

    A novel heptapeptide comprising Ile-Gln-Ser-Pro-His-Phe-Phe (IQSPHFF) identified and found to undergo self-assembly into microparticles in solution. To understand the effects of ultraviolet (UV) irradiation on the self-assembly process, IQSPHFF solutions were exposed to the UV light of 365 nm at room temperature. This exposure was found to have a profound effect on the morphology of the self-assembled aggregates, converting the microparticles to nanorod shapes. Circular dichroism and FTIR studies indicated distinct structural differences in the arrangements of the peptide moieties before and after UV irradiation. However, Mass spectrum analysis and high performance liquid chromatography of the peptide molecules before and after UV irradiation demonstrated that the chemical structure of IQSPHFF was not changed. UV-visible spectroscopy and fluorescence spectroscopy studies showed that the absorption peak both increased after UV irradiation. Overall, our data show that the heptapeptide with UV-responsive properties. PMID:23828220

  17. Metal Organic Vapor Phase Epitaxy of Monolithic Two-Color Light-Emitting Diodes Using an InGaN-Based Light Converter

    NASA Astrophysics Data System (ADS)

    Damilano, Benjamin; Kim-Chauveau, Hyonju; Frayssinet, Eric; Brault, Julien; Hussain, Sakhawat; Lekhal, Kaddour; Vennéguès, Philippe; De Mierry, Philippe; Massies, Jean

    2013-09-01

    Monolithic InGaN-based light-emitting diodes (LEDs) using a light converter fully grown by metal organic vapor phase epitaxy are demonstrated. The light converter, consisting of 10-40 InGaN/GaN quantum wells, is grown first, followed by a violet pump LED. The structure and growth conditions of the pump LED are specifically adapted to avoid thermal degradation of the light converter. Electroluminescence analysis shows that part of the pump light is absorbed by the light converter and reemitted at longer wavelength. Depending on the emission wavelength of the light converter, different LED colors are achieved. In particular, for red-emitting light converters, a color temperature of 2100 K corresponding to a tint between warm white and candle light is demonstrated.

  18. Are You UV Safe?

    ERIC Educational Resources Information Center

    Capobianco, Brenda; Thiel, Elizabeth Andrew

    2006-01-01

    Students may be slathered with SPF 30 sunscreen all summer at the beach or pool, but what do they know about ultraviolet (UV) light radiation and absorption? The authors of this article found the perfect opportunity to help students find out the science behind this important health precaution, when they developed a series of practical strategies…

  19. Mach-Zehnder Interferometric Wavelength Converter as a Pseudo Return-to-Zero Extractor

    NASA Astrophysics Data System (ADS)

    Kim, Dong Churl; Leem, Young Ahn; Sim, Eun Deok; Yee, Dae-Su; Ko, Hyun Sung; Kim, Sung-bock; Park, Kyung Hyun; Jeon, Min Yong

    2007-05-01

    We have used semiconductor optical amplifier (SOA)-based Mach-Zehnder interferometric wavelength converter (MZ-IWC) as a pseudo return-to-zero (PRZ) extractor. Applying this scheme, PRZ was extracted from non-return-to-zero pump beam after MZ-IWC and optical clock was recovered by injection-locking a self-pulsating laser diode with the extracted PRZ. In addition, a wavelength-converted signal was obtained from probe beam.

  20. [Using UV pretreatment to enhance biofiltration of chlorobenzene].

    PubMed

    Cheng, Zhuo-wei; Lin, Wen-wen; Jiang, Yi-feng; Chen, Jian-meng; Zhang, Li-li; Zhang, Hua

    2010-05-01

    Purification of chlorobenzene by ultraviolet-biotrickling filter (UV-BTF) was studied in this paper. The light source and the biofilm carrier were an ozone producing lamp with a maximum emission (> 99%) at 185nm and the ether-based polyurethane foam (PU-foam), respectively. When the residence time were 92, 69 and 46s, with the chlorobenzene concentration of 600 mg x m(-3), the average removal efficiencies were 99%, 95% and 80%, respectively while the maximum removal load was 59.6 g x (m3 x h)(-1). The biofilm formed in the UV-BTF was 20 d, shorter than that of the sole BTF (27 d). Compared with the sole BTF, the UV-BTF had strong resistance to load shock. When the residence time was shortened to 30s, the removal efficiency of UV-BTF achieved over 75%, higher than that of sole BTF (25%). Considering the mechanism of the UV-BTF process, the UV converted the chlorobenzene into more soluble and biodegradable intermediates, thus the removal load by BTF decreased. Meanwhile, the ozone produced during the UV photolysis could control the microorganism growth in the BTF, keeping the whole system in optimal operation. PMID:20623846

  1. Fiber-Based, Spatially and Temporally Shaped Picosecond UV Laser for Advanced RF Gun Applications

    SciTech Connect

    Shverdin, M Y; Anderson, S G; Betts, S M; Gibson, D J; Hartemann, F V; Hernandez, J E; Johnson, M; Jovanovic, I; Messerly, M; Pruet, J; Tremaine, A M; McNabb, D P; Siders, C W; Barty, C J

    2007-06-08

    The fiber-based, spatially and temporally shaped, picosecond UV laser system described here has been specifically designed for advanced rf gun applications, with a special emphasis on the production of high-brightness electron beams for free-electron lasers and Compton scattering light sources. The laser pulse can be shaped to a flat-top in both space and time with a duration of 10 ps at full width of half-maximum (FWHM) and rise and fall times under 1 ps. The expected pulse energy is 50 {micro}J at 261.75 nm and the spot size diameter of the beam at the photocathode is 2 mm. A fiber oscillator and amplifier system generates a chirped pump pulse at 1047 nm; stretching is achieved in a chirped fiber Bragg grating. A single multi-layer dielectric grating based compressor recompresses the input pulse to 250 fs FWHM and a two stage harmonic converter frequency quadruples the beam. Temporal shaping is achieved with a Michelson-based ultrafast pulse stacking device with nearly 100% throughput. Spatial shaping is achieved by truncating the beam at the 20% energy level with an iris and relay-imaging the resulting beam profile onto the photocathode. The integration of the system, as well as preliminary laser measurements will be presented.

  2. Wind/water energy converter

    NASA Technical Reports Server (NTRS)

    Paulkovich, J.

    1979-01-01

    Device will convert wind, water, tidal or wave energy into electrical or mechanical energy. Is comprised of windmill-like paddles or blades synchronously geared to orient themselves to wind direction for optimum energy extraction.

  3. Evaluation of a UV/Ozone Treatment Process for Removal of MTBE in Groundwater Supplies in New Mexico

    EPA Science Inventory

    EPA’s Office of Research and Development is funding pilot-scale studies on MTBE contaminated groundwater using UV/ozone treatment technology (254 nm UV, 5.8 mg/L ozone). The pilot-scale treatment system consists of a GW well pump, a feed tank, a pretreatment system (water soften...

  4. Evaluation of a UV/Ozone Treatment Process for Removal of MTBE in Groundwater Supplies in New Mexico

    EPA Science Inventory

    EPA’s Office of Research and Development is funding pilot-scale studies on MTBE contaminated groundwater using UV/ozone treatment technology (254 nm UV, 5.8 mg/L ozone). The pilot-scale treatment system consists of a GW well pump, a feed tank, a pretreatment system (water softene...

  5. Boron nitride converted carbon fiber

    DOEpatents

    Rousseas, Michael; Mickelson, William; Zettl, Alexander K.

    2016-04-05

    This disclosure provides systems, methods, and apparatus related to boron nitride converted carbon fiber. In one aspect, a method may include the operations of providing boron oxide and carbon fiber, heating the boron oxide to melt the boron oxide and heating the carbon fiber, mixing a nitrogen-containing gas with boron oxide vapor from molten boron oxide, and converting at least a portion of the carbon fiber to boron nitride.

  6. Electrokinetic pumps and actuators

    SciTech Connect

    Phillip M. Paul

    2000-03-01

    Flow and ionic transport in porous media are central to electrokinetic pumping as well as to a host of other microfluidic devices. Electrokinetic pumping provides the ability to create high pressures (to over 10,000 psi) and high flow rates (over 1 mL/min) with a device having no moving parts and all liquid seals. The electrokinetic pump (EKP) is ideally suited for applications ranging from a high pressure integrated pump for chip-scale HPLC to a high flow rate integrated pump for forced liquid convection cooling of high-power electronics. Relations for flow rate and current fluxes in porous media are derived that provide a basis for analysis of complex microfluidic systems as well as for optimization of electrokinetic pumps.

  7. Rotary blood pump

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J. (Inventor); Akkerman, James W. (Inventor); Aber, Greg S. (Inventor); Vandamm, George A. (Inventor); Bacak, James W. (Inventor); Svejkovsky, Paul A. (Inventor); Benkowski, Robert J. (Inventor)

    1993-01-01

    A rotary blood pump is presented. The pump includes a pump housing for receiving a flow straightener, a rotor mounted on rotor bearings and having an inducer portion and an impeller portion, and a diffuser. The entrance angle, outlet angle, axial, and radial clearances of the blades associated with the flow straightener, inducer portion, impeller portion, and diffuser are optimized to minimize hemolysis while maintaining pump efficiency. The rotor bearing includes a bearing chamber that is filled with crosslinked blood or other bio-compatible material. A back emf integrated circuit regulates rotor operation and a microcomputer may be used to control one or more back emf integrated circuits. A plurality of magnets are disposed in each of a plurality of impeller blades with a small air gap. A stator may be axially adjusted on the pump housing to absorb bearing load and maximize pump efficiency.

  8. DIRECT CURRENT ELECTROMAGNETIC PUMP

    DOEpatents

    Barnes, A.H.

    1957-11-01

    An improved d-c electromagnetic pump is presented in which the poles, and consequently the magetic gap at the poles, are tapered to be wider at the upstream end. In addition, the cross section of the tube carryiQ the liquid metal is tapered so that the velocity of the pumped liquid increases in the downstream direction at a rate such that the counter-induced voltage in the liquid metal remains constant as it traverses the region between the poles. This configuration compensates for the distortion of the magnetic field caused by the induced voltage that would otherwise result in the lowering of the pumping capacity. This improved electromagnetic pump as practical application in the pumping of liquid metal coolants for nuclear reactors where conventional positive displacement pumps have proved unsatisfactory due to the high temperatures and the corrosive properties of the liquid metals involved.

  9. Pump isolation valve

    DOEpatents

    Kinney, Calvin L.; Wetherill, Todd M.

    1983-08-02

    The pump isolation valve provides a means by which the pump may be selectively isolated from the remainder of the coolant system while being compatible with the internal hydraulic arrangement of the pump during normal operation of the pump. The valve comprises a valve cylinder disposed around the pump and adjacent to the last pump diffuser with a turning vane attached to the lower end of the valve cylinder in a manner so as to hydraulically match with the discharge diffuser. The valve cylinder is connected to a drive means for sliding the valve cylinder relative to the diffuser support cylinder so as to block flow in either direction through the discharge diffuser when the valve is in the closed position and to aid in the flow of the coolant from the discharge diffuser by means of the turning vane when the valve is in the open position.

  10. A compact cryogenic pump

    NASA Astrophysics Data System (ADS)

    Li, Gang; Caldwell, Shane; Clark, Jason A.; Gulick, Sidney; Hecht, Adam; Lascar, Daniel D.; Levand, Tony; Morgan, Graeme; Orford, Rodney; Savard, Guy; Sharma, Kumar S.; Van Schelt, Jonathon

    2016-04-01

    A centrifugal cryogenic pump has been designed at Argonne National Laboratory to circulate liquid nitrogen (LN2) in a closed circuit allowing the recovery of excess fluid. The pump can circulate LN2 at rates of 2-10 L/min, into a head of 0.5-3 m. Over four years of laboratory use the pump has proven capable of operating continuously for 50-100 days without maintenance.

  11. Detection of pump degradation

    SciTech Connect

    Greene, R.H.; Casada, D.A.; Ayers, C.W.

    1995-08-01

    This Phase II Nuclear Plant Aging Research study examines the methods of detecting pump degradation that are currently employed in domestic and overseas nuclear facilities. This report evaluates the criteria mandated by required pump testing at U.S. nuclear power plants and compares them to those features characteristic of state-of-the-art diagnostic programs and practices currently implemented by other major industries. Since the working condition of the pump driver is crucial to pump operability, a brief review of new applications of motor diagnostics is provided that highlights recent developments in this technology. The routine collection and analysis of spectral data is superior to all other technologies in its ability to accurately detect numerous types and causes of pump degradation. Existing ASME Code testing criteria do not require the evaluation of pump vibration spectra but instead overall vibration amplitude. The mechanical information discernible from vibration amplitude analysis is limited, and several cases of pump failure were not detected in their early stages by vibration monitoring. Since spectral analysis can provide a wealth of pertinent information concerning the mechanical condition of rotating machinery, its incorporation into ASME testing criteria could merit a relaxation in the monthly-to-quarterly testing schedules that seek to verify and assure pump operability. Pump drivers are not included in the current battery of testing. Operational problems thought to be caused by pump degradation were found to be the result of motor degradation. Recent advances in nonintrusive monitoring techniques have made motor diagnostics a viable technology for assessing motor operability. Motor current/power analysis can detect rotor bar degradation and ascertain ranges of hydraulically unstable operation for a particular pump and motor set. The concept of using motor current or power fluctuations as an indicator of pump hydraulic load stability is presented.

  12. Fakir fuel pump

    NASA Technical Reports Server (NTRS)

    1922-01-01

    In designing the Fakir fuel pump, the fundamental idea was to obtain a simple and reliable method of conveying the fuel from a low tank to the carburetor, with the avoidance of the faults of all former methods and the simultaneous warming of the fuel by means of the heat of compression generated. The principle of the Fakir fuel pump rests on the well-known principle of the diaphragm pump, which must be suitably adapted to the present purpose.

  13. Asymmetric Functional Conversion of Eubacterial Light-driven Ion Pumps.

    PubMed

    Inoue, Keiichi; Nomura, Yurika; Kandori, Hideki

    2016-05-01

    In addition to the well-known light-driven outward proton pumps, novel ion-pumping rhodopsins functioning as outward Na(+) and inward Cl(-) pumps have been recently found in eubacteria. They convert light energy into transmembrane electrochemical potential difference, similar to the prototypical archaeal H(+) pump bacteriorhodopsin (BR) and Cl(-) pump halorhodopsin (HR). The H(+), Na(+), and Cl(-) pumps possess the conserved respective DTE, NDQ, and NTQ motifs in the helix C, which likely serve as their functional determinants. To verify this hypothesis, we attempted functional interconversion between selected pumps from each category by mutagenesis. Introduction of the proton-pumping motif resulted in successful Na(+) → H(+) functional conversion. Introduction of the respective characteristic motifs with several additional mutations leads to successful Na(+) → Cl(-) and Cl(-) → H(+) functional conversions, whereas remaining conversions (H(+) → Na(+), H(+) → Cl(-), Cl(-) → Na(+)) were unsuccessful when mutagenesis of 4-6 residues was used. Phylogenetic analysis suggests that a H(+) pump is the common ancestor of all of these rhodopsins, from which Cl(-) pumps emerged followed by Na(+) pumps. We propose that successful functional conversions of these ion pumps are achieved exclusively when mutagenesis reverses the evolutionary amino acid sequence changes. Dependence of the observed functional conversions on the direction of evolution strongly suggests that the essential structural mechanism of an ancestral function is retained even after the gain of a new function during natural evolution, which can be evoked by a few mutations. By contrast, the gain of a new function needs accumulation of multiple mutations, which may not be easily reproduced by limited mutagenesis in vitro. PMID:26929409

  14. UV curable materials development

    SciTech Connect

    Parker, B.G.

    1996-12-01

    Adhesives, coatings, and inks were selected for evaluation based on literature search and possible production applications. A differential photocalorimeter was used to measure degree of cure and allow prediction of optimum processing conditions. UV cure equipment were characterized and the ability to size equipment to specific materials cure needs established. Adhesion tests procedures were developed for the adhesives and solvent resistance testing procedures developed for the coatings and inks.

  15. uv preilluminated gas switches

    SciTech Connect

    Bradley, L.P.; Orham, E.L.; Stowers, I.F.; Braucht, J.R.

    1980-06-03

    We have designed, built, and characterized uv preilluminated gas switches for a trigger circuit and a low inductance discharge circuit. These switches have been incorporated into a 54 x 76 x 150 cm pulser module to produce a 1 Ma output current rising at 5 x 10/sup 12/ amps/sec with 1 ns jitter. Twenty such modules will be used on the Nova Inertial Confinement Fusion Laser System for plasma retropulse shutters.

  16. Detection of pump degradation

    SciTech Connect

    Casada, D.

    1995-04-01

    There are a variety of stressors that can affect the operation of centrifugal pumps. Although these general stressors are active in essentially all centrifugal pumps, the stressor level and the extent of wear and degradation can vary greatly. Parameters that affect the extent of stressor activity are manifold. In order to assure the long-term operational readiness of a pump, it is important to both understand the nature and magnitude of the specific degradation mechanisms and to monitor the performance of the pump. The most commonly applied method of monitoring the condition of not only pumps, but rotating machinery in general, is vibration analysis. Periodic or continuous special vibration analysis is a cornerstone of most pump monitoring programs. In the nuclear industry, non-spectral vibration monitoring of safety-related pumps is performed in accordance with the ASME code. Pump head and flow rate are also monitored, per code requirements. Although vibration analysis has dominated the condition monitoring field for many years, there are other measures that have been historically used to help understand pump condition; advances in historically applied technologies and developing technologies offer improved monitoring capabilities. The capabilities of several technologies (including vibration analysis, dynamic pressure analysis, and motor power analysis) to detect the presence and magnitude of both stressors and resultant degradation are discussed.

  17. Submersible sodium pump

    DOEpatents

    Brynsvold, Glen V.; Lopez, John T.; Olich, Eugene E.; West, Calvin W.

    1989-01-01

    An electromagnetic submerged pump has an outer cylindrical stator with an inner cylindrical conductive core for the submerged pumping of sodium in the cylindrical interstitial volume defined between the stator and core. The cylindrical interstitial volume is typically vertically oriented, and defines an inlet at the bottom and an outlet at the top. The outer stator generates upwardly conveyed toroidal magnetic fields, which fields convey preferably from the bottom of the pump to the top of the pump liquid sodium in the cold leg of a sodium cooled nuclear reactor. The outer cylindrical stator has a vertically disposed duct surrounded by alternately stacked layers of coil units and laminates.

  18. Submersible sodium pump

    DOEpatents

    Brynsvold, G.V.; Lopez, J.T.; Olich, E.E.; West, C.W.

    1989-11-21

    An electromagnetic submerged pump has an outer cylindrical stator with an inner cylindrical conductive core for the submerged pumping of sodium in the cylindrical interstitial volume defined between the stator and core. The cylindrical interstitial volume is typically vertically oriented, and defines an inlet at the bottom and an outlet at the top. The outer stator generates upwardly conveyed toroidal magnetic fields, which fields convey preferably from the bottom of the pump to the top of the pump liquid sodium in the cold leg of a sodium cooled nuclear reactor. The outer cylindrical stator has a vertically disposed duct surrounded by alternately stacked layers of coil units and laminates. 14 figs.

  19. Champagne Heat Pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    2004-01-01

    The term champagne heat pump denotes a developmental heat pump that exploits a cycle of absorption and desorption of carbon dioxide in an alcohol or other organic liquid. Whereas most heat pumps in common use in the United States are energized by mechanical compression, the champagne heat pump is energized by heating. The concept of heat pumps based on other absorption cycles energized by heat has been understood for years, but some of these heat pumps are outlawed in many areas because of the potential hazards posed by leakage of working fluids. For example, in the case of the water/ammonia cycle, there are potential hazards of toxicity and flammability. The organic-liquid/carbon dioxide absorption/desorption cycle of the champagne heat pump is similar to the water/ammonia cycle, but carbon dioxide is nontoxic and environmentally benign, and one can choose an alcohol or other organic liquid that is also relatively nontoxic and environmentally benign. Two candidate nonalcohol organic liquids are isobutyl acetate and amyl acetate. Although alcohols and many other organic liquids are flammable, they present little or no flammability hazard in the champagne heat pump because only the nonflammable carbon dioxide component of the refrigerant mixture is circulated to the evaporator and condenser heat exchangers, which are the only components of the heat pump in direct contact with air in habitable spaces.

  20. Transverse effects in UV FELs

    SciTech Connect

    Small, D.W.; Wong, R.K.; Colson, W.B.

    1995-12-31

    In an ultraviolet Free Electron Laser (UV FEL), the electron beam size can be approximately the same as the optical mode size. The performance of a UV FEL is studied including the effect of emittance, betatron focusing, and external focusing of the electron beam on the transverse optical mode. The results are applied to the Industrial Laser Consortium`s UV FEL.

  1. Radiation effects on DC-DC Converters

    NASA Technical Reports Server (NTRS)

    Zhang, Dexin; Attia, John O.; Kankam, Mark D. (Technical Monitor)

    2000-01-01

    DC-DC switching converters are circuits that can be used to convert a DC voltage of one value to another by switching action. They are increasing being used in space systems. Most of the popular DC-DC switching converters utilize power MOSFETs. However power MOSFETs, when subjected to radiation, are susceptible to degradation of device characteristics or catastrophic failure. This work focuses on the effects of total ionizing dose on converter performance. Four fundamental switching converters (buck converter, buck-boost converter, cuk converter, and flyback converter) were built using Harris IRF250 power MOSFETs. These converters were designed for converting an input of 60 volts to an output of about 12 volts with a switching frequency of 100 kHz. The four converters were irradiated with a Co-60 gamma source at dose rate of 217 rad/min. The performances of the four converters were examined during the exposure to the radiation. The experimental results show that the output voltage of the converters increases as total dose increases. However, the increases of the output voltage were different for the four different converters, with the buck converter and cuk converter the highest and the flyback converter the lowest. We observed significant increases in output voltage for cuk converter at a total dose of 24 krad (si).

  2. Liquid pump for astronaut cooling

    NASA Technical Reports Server (NTRS)

    Carson, M. A.

    1972-01-01

    The Apollo portable life support system water-recirculation pump used for astronaut cooling is described. The problems associated with an early centrifugal pump and how these problems were overcome by the use of a new diaphragm pump are discussed. Performance comparisons of the two pump designs are given. Developmental problems and flight results with the diaphragm pump are discussed.

  3. Well-pump alignment system

    DOEpatents

    Drumheller, Douglas S.

    1998-01-01

    An improved well-pump for geothermal wells, an alignment system for a well-pump, and to a method for aligning a rotor and stator within a well-pump, wherein the well-pump has a whistle assembly formed at a bottom portion thereof, such that variations in the frequency of the whistle, indicating misalignment, may be monitored during pumping.

  4. Solar-pumped gas laser development

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.

    1980-01-01

    A survey of gas properties through detailed kinetic models led to the identification of critical gas parameters for use in choosing appropriate gas combinations for solar pumped lasers. Broadband photoabsorption in the visible or near UV range is required to excite large volumes of gas and to insure good solar absorption efficiency. The photoexcitation density is independent of the absorption bandwidth. The state excited must be a metastable state which is not quenched by the parent gas. The emission bandwidth must be less than 10 A to insure lasing threshold over reasonable gain lengths. The system should show a high degree of chemical reversibility and an insensitivity to increasing temperature. Other properties such as good quantum efficiency and kinetic efficiency are also implied. Although photoexcitation of electronic vibrational transitions is considered as a possible system if the emission bands sufficiently narrow, it appears that photodissociation into atomic metastables is more likely to result in a successful solar pumped laser system.

  5. Looking south at boiler feedwater pumps (steam turbine pump on ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking south at boiler feedwater pumps (steam turbine pump on left, electric motor pump on right). - Wheeling-Pittsburgh Steel Corporation, Allenport Works, Boiler House, Route 88 on West bank of Monongahela River, Allenport, Washington County, PA

  6. 98. VIEW OF PUMPS FROM NORTH. MILL SOLUTION PUMP No. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    98. VIEW OF PUMPS FROM NORTH. MILL SOLUTION PUMP No. 2 IN FOREGROUND, ABANDONED BARREN SOLUTION PUMP BEYOND. AGITATOR No. 1 IN BACKGROUND. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  7. 32. PLAN OF DEER ISLAND PUMPING STATION SHOWING EXISTING PUMPING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    32. PLAN OF DEER ISLAND PUMPING STATION SHOWING EXISTING PUMPING PLANT AND LOCATION OF PROPOSED ADDITIONS, JULY 1898 SHEET NO. 1. Aperture card 4966-1 - Deer Island Pumping Station, Boston, Suffolk County, MA

  8. 33. PLAN OF DEER ISLAND PUMPING STATION SHOWING EXISTING PUMPING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    33. PLAN OF DEER ISLAND PUMPING STATION SHOWING EXISTING PUMPING PLAN AND LOCATION OF PROPOSED ADDITIONS, METROPOLITAN WATER AND SEWERAGE BOARD, METROPOLITAN SEWERAGE WORKS, JULY 1908. Aperture card 6417. - Deer Island Pumping Station, Boston, Suffolk County, MA

  9. Diaphragm Pump With Resonant Piezoelectric Drive

    NASA Technical Reports Server (NTRS)

    Izenson, Michael G.; Kline-Schoder, Robert J.; Shimko, Martin A.

    2007-01-01

    make it oscillate at the resonance frequency of the spring and- mass structure. This frequency could be made high enough (of the order of 400 Hz) that the masses of all components could be made conveniently small. The resonance would amplify the relatively small motion of the piezoelectric stack (a stroke of the order of 10 m) to a diaphragm stroke of the order of 0.5 mm. The exact amplification factor would depend on the rate of damping of oscillations; this, in turn, would depend on details of design and operation, including (but not limited to) the desired pressure rise and volumetric flow rate. In order to obtain resonance with large displacement, the damping rate must be low enough that the energy imparted to the pumped fluid on each stroke is much less than the kinetic and potential energy exchanged between the mass and spring during each cycle of oscillation. To minimize the power demand of the pump, a highly efficient drive circuit would be used to excite the piezoelectric stack. This circuit (see Figure 2) would amount to a special-purpose regenerative, switching power supply that would operate in a power-source mode during the part of an oscillation cycle when the excitation waveform was positive and in a power-recovery mode during the part of the cycle when the excitation waveform was negative. The circuit would include a voltage-boosting dc-to-dc converter that would convert between a supply potential of 24 Vdc and the high voltage needed to drive the piezoelectric stack. Because of the power-recovery feature, the circuit would consume little power. It should be possible to build the circuit as a compact unit, using readily available components.

  10. Pump apparatus including deconsolidator

    DOEpatents

    Sonwane, Chandrashekhar; Saunders, Timothy; Fitzsimmons, Mark Andrew

    2014-10-07

    A pump apparatus includes a particulate pump that defines a passage that extends from an inlet to an outlet. A duct is in flow communication with the outlet. The duct includes a deconsolidator configured to fragment particle agglomerates received from the passage.

  11. Detection of pump degradation

    SciTech Connect

    Casada, D.

    1994-12-31

    There are a variety of stressors that can affect the operation of centrifugal pumps. Although these general stressors are active in essentially all centrifugal pumps, the stressor level and the extent of wear and degradation can vary greatly. Parameters that affect the extent of stressor activity are manifold. In order to assure the long-term operational readiness of a pump, it is important to both understand the nature and magnitude of the specific degradation mechanisms and to monitor the performance of the pump. The most commonly applied method of monitoring the condition of not only pumps, but rotating machinery in general, is vibration analysis. Periodic or continuous spectral vibration analysis is a cornerstone of most pump monitoring programs. In the nuclear industry, non-spectral vibration monitoring of safety-related pumps is performed in accordance with the ASME code. Although vibration analysis has dominated the condition monitoring field for many years, there are other measures that have been historically used to help understand pump condition: advances in historically applied technologies and developing technologies offer improved monitoring capabilities. The capabilities of several technologies (including vibration analysis, dynamic pressure analysis, and motor power analysis) to detect the presence and magnitude of both stressors and resultant degradation are discussed.

  12. Micromachined peristaltic pumps

    NASA Technical Reports Server (NTRS)

    Hartley, Frank T. (Inventor)

    1999-01-01

    Micromachined pumps including a channel formed between a first membrane and a substrate or between first and second flexible membranes. A series of electrically conductive strips is applied to a surface of the substrate or one of the membranes. Application of a sequential voltage to the series of strips causes a region of closure to progress down the channel to achieve a pumping action.

  13. Water Treatment Technology - Pumps.

    ERIC Educational Resources Information Center

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on pumps provides instructional materials for three competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: types of pumps in plant and distribution systems, pump…

  14. NEUTRONIC REACTOR FUEL PUMP

    DOEpatents

    Cobb, W.G.

    1959-06-01

    A reactor fuel pump is described which offers long life, low susceptibility to radiation damage, and gaseous fission product removal. An inert-gas lubricated bearing supports a journal on one end of the drive shsft. The other end has an impeller and expansion chamber which effect pumping and gas- liquid separation. (T.R.H.)

  15. A Shocking New Pump

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Hydro Dynamics, Inc. received a technical helping hand from NASA that made their Hydrosonic Pump (HPump) a reality. Marshall engineers resolved a bearing problem in the rotor of the pump and recommended new bearings, housings and mounting hardware as a solution. The resulting HPump is able to heat liquids with greater energy efficiency using shock waves to generate heat.

  16. All-Solid-State UV Transmitter Development for Ozone Sensing Applications

    NASA Technical Reports Server (NTRS)

    Prasad, Narasimha S.; Singh, Upendra N.; Armstrong, Darrell Jr.

    2009-01-01

    In this paper, recent progress made in the development of an all-solid-state UV transmitter suitable for ozone sensing applications from space based platforms is discussed. A nonlinear optics based UV setup based on Rotated Image Singly Resonant Twisted Rectangle (RISTRA) optical parametric oscillator (OPO) module was effectively coupled to a diode pumped, single longitudinal mode, conductively cooled, short-pulsed, high-energy Nd:YAG laser operating at 1064 nm with 50 Hz PRF. An estimated 10 mJ/pulse with 10% conversion efficiency at 320 nm has been demonstrated limited only by the pump pulse spatial profile. The current arrangement has the potential for obtaining greater than 200 mJ/pulse. Previously, using a flash-lamp pumped Nd:YAG laser with round, top-hat profile, up to 24% IR-UV conversion efficiency was achieved with the same UV module. Efforts are underway to increase the IR-UV conversion efficiency of the all solid-state setup by modifying the pump laser spatial profile along with incorporating improved OPO crystals.

  17. Electrically Injected UV-Visible Nanowire Lasers

    SciTech Connect

    Wang, George T.; Li, Changyi; Li, Qiming; Liu, Sheng; Wright, Jeremy Benjamin; Brener, Igal; Luk, Ting -Shan; Chow, Weng W.; Leung, Benjamin; Figiel, Jeffrey J.; Koleske, Daniel D.; Lu, Tzu-Ming

    2015-09-01

    There is strong interest in minimizing the volume of lasers to enable ultracompact, low-power, coherent light sources. Nanowires represent an ideal candidate for such nanolasers as stand-alone optical cavities and gain media, and optically pumped nanowire lasing has been demonstrated in several semiconductor systems. Electrically injected nanowire lasers are needed to realize actual working devices but have been elusive due to limitations of current methods to address the requirement for nanowire device heterostructures with high material quality, controlled doping and geometry, low optical loss, and efficient carrier injection. In this project we proposed to demonstrate electrically injected single nanowire lasers emitting in the important UV to visible wavelengths. Our approach to simultaneously address these challenges is based on high quality III-nitride nanowire device heterostructures with precisely controlled geometries and strong gain and mode confinement to minimize lasing thresholds, enabled by a unique top-down nanowire fabrication technique.

  18. Normetex Pump Alternatives Study

    SciTech Connect

    Clark, Elliot A.

    2013-04-25

    A mainstay pump for tritium systems, the Normetex scroll pump, is currently unavailable because the Normetex company went out of business. This pump was an all-metal scroll pump that served tritium processing facilities very well. Current tritium system operators are evaluating replacement pumps for the Normetex pump and for general used in tritium service. An all-metal equivalent alternative to the Normetex pump has not yet been identified. 1. The ideal replacement tritium pump would be hermetically sealed and contain no polymer components or oils. Polymers and oils degrade over time when they contact ionizing radiation. 2. Halogenated polymers (containing fluorine, chlorine, or both) and oils are commonly found in pumps. These materials have many properties that surpass those of hydrocarbon-based polymers and oils, including thermal stability (higher operating temperature) and better chemical resistance. Unfortunately, they are less resistant to degradation from ionizing radiation than hydrocarbon-based materials (in general). 3. Polymers and oils can form gaseous, condensable (HF, TF), liquid, and solid species when exposed to ionizing radiation. For example, halogenated polymers form HF and HCl, which are extremely corrosive upon reaction with water. If a pump containing polymers or oils must be used in a tritium system, the system must be designed to be able to process the unwanted by-products. Design features to mitigate degradation products include filters and chemical or physical traps (eg. cold traps, oil traps). 4. Polymer components can work in tritium systems, but must be replaced regularly. Polymer components performance should be monitored or be regularly tested, and regular replacement of components should be viewed as an expected normal event. A radioactive waste stream must be established to dispose of used polymer components and oil with an approved disposal plan developed based on the facility location and its regulators. Polymers have varying

  19. Rotary Blood Pump

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J., Jr. (Inventor); Akkerman, James W. (Inventor); Aber, Gregory S. (Inventor); VanDamm, George A. (Inventor); Bacak, James W. (Inventor); Svejkovsky, Paul A. (Inventor); Benkowski, Robert J. (Inventor)

    1996-01-01

    A rotary blood pump includes a pump housing for receiving a flow straightener, a rotor mounted on rotor bearings and having an inducer portion and an impeller portion, and a diffuser. The entrance angle, outlet angle, axial and radial clearances of blades associated with the flow straightener, inducer portion, impeller portion and diffuser are optimized to minimize hemolysis while maintaining pump efficiency. The rotor bearing includes a bearing chamber that is filled with cross-linked blood or other bio-compatible material. A back emf integrated circuit regulates rotor operation and a microcomputer may be used to control one or more back emf integrated circuits. A plurality of magnets are disposed in each of a plurality of impeller blades with a small air gap. A stator may be axially adjusted on the pump housing to absorb bearing load and maximize pump efficiency.

  20. Deep well solar pump

    SciTech Connect

    Vanek, J.

    1990-02-06

    This patent describes, in a pump having a source of gas under pressure, and a gas operated pump, a mechanism periodically injecting gas from the source of gas into the gas operated pump. It comprises: a long period pendulum turning towards a first position by gravity, an injection valve connected between the source of gas under pressure and the gas operated pump, a linkage between the pendulum and the injection valve. The linkage opening the injection valve when the pendulum is in the first position, an impulse tube connected between the injection valve and the gas operated pump, a member having a surface adjacent to the first position of the pendulum, and an elastic impulse bladder connected to the impulse tube adjacent to the surface so that inflation of the impulse bladder on the opening of the injection valve forces the impulse bladder against the pendulum urging the pendulum against the force of gravity toward a second position.

  1. High efficiency thermionic converter studies

    NASA Technical Reports Server (NTRS)

    Huffman, F. N.; Sommer, A. H.; Balestra, C. L.; Briere, T. R.; Lieb, D.; Oettinger, P. E.; Goodale, D. B.

    1977-01-01

    Research in thermionic energy conversion technology is reported. The objectives were to produce converters suitable for use in out of core space reactors, radioisotope generators, and solar satellites. The development of emitter electrodes that operate at low cesium pressure, stable low work function collector electrodes, and more efficient means of space charge neutralization were investigated to improve thermionic converter performance. Potential improvements in collector properties were noted with evaporated thin film barium oxide coatings. Experiments with cesium carbonate suggest this substance may provide optimum combinations of cesium and oxygen for thermionic conversion.

  2. Graphene optical-to-thermal converter

    NASA Astrophysics Data System (ADS)

    Manjavacas, Alejandro; Thongrattanasiri, Sukosin; Greffet, Jean-Jacques; Garcia de Abajo, Javier

    2015-03-01

    Infrared plasmons in doped graphene nanostructures produce large optical absorption that can be used for narrow-band thermal light emission at tunable frequencies that strongly depend on the doping charge. By virtue of Kirchhoff's law, thermal light emission is proportional to the absorption, thus resulting in narrow emission lines associated with the electrically controlled plasmons of heated graphene. Here we show that realistic designs of graphene plasmonic structures can release over 90% of the emission through individual infrared lines with 1% bandwidth. We examine anisotropic graphene structures in which efficient heating can be produced upon optical pumping tuned to a plasmonic absorption resonance situated in the blue region relative to the thermal emission. An incoherent thermal light converter is thus achieved. Our results open a new approach for designing tunable nanoscale infrared light sources. A.M. acknowledges financial support from the Welch foundation through the J. Evans Attwell-Welch Postdoctoral Fellowship Program of the Smalley Institute of Rice University (Grant L-C-004).

  3. Microbial fuel cell energy harvesting using synchronous flyback converter

    NASA Astrophysics Data System (ADS)

    Alaraj, Muhannad; Ren, Zhiyong Jason; Park, Jae-Do

    2014-02-01

    Microbial Fuel Cells (MFCs) use biodegradable substrates, such as wastewater and marine sediments to generate electrical energy. To harvest more energy from an MFC, power electronic converters have recently been used to replace resistors or charge pumps, because they have superior controllability on MFC's operating point and higher efficiency in energy storage for different applications. Conventional diode-based energy harvesters suffer from low efficiency because of the energy losses through the diode. Replacing the diode with a MOSFET can reduce the conduction loss, but it requires an isolated gate signal to control the floating secondary MOSFET, which makes the control circuitry complex. This study presents a new MFC energy harvesting regime using a synchronous flyback converter, which implements a transformer-based harvester with much simpler configuration and improves harvesting efficiency by 37.6% compared to a diode based boost converter, from 33.5% to 46.1%. The proposed harvester was able to store 2.27 J in the output capacitor out of 4.91 J generated energy from the MFC, while the boost converter can capture 1.67 J from 4.95 J.

  4. Apparatus for Pumping a Fluid

    NASA Technical Reports Server (NTRS)

    Boeyen, Robert Van; Reeh, Jonathan

    2013-01-01

    A fluid pump has been developed for mechanically pumped fluid loops for spacecraft thermal control. Lynntech's technology utilizes a proprietary electrochemically driven pumping mechanism. Conventional rotodynamic and displacement pumps typically do not meet the stringent power and operational reliability requirements of space applications. Lynntech's developmental pump is a highly efficient solid-state pump with essentially no rotating or moving components (apart from metal bellows).

  5. Uvs Nuur, Mongolia

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The Uvs Nuur Basin in Mongolia and the Russian Federation is the northernmost of the enclosed basins of Central Asia. It takes its name from Uvs Nuur Lake, a large, shallow and very saline lake, very important for migrating birds. Inscribed as a UNESCO World Heritage Site in 2003, the site is made up of twelve protected areas representing major biomes of eastern Eurasia. The steppe ecosystem supports a rich diversity of birds and the desert is home to a number of rare gerbil, jerboas and the marbled polecat. The mountains are an important refuge for the endangered snow leopard, mountain sheep, and the Asiatic ibex.

    The image covers an area of 46 x 47.8 km, was acquired on September 4, 2001, and is located near 50.3 degrees north latitude, 90.7 degrees east longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  6. Inlet and outlet devices for rotary blood pumps.

    PubMed

    Song, Xinwei; Wood, Houston G; Allaire, Paul E; Antaki, James F; Olsen, Don B

    2004-10-01

    The purposes of inlet and outlet devices for rotary blood pumps, including inducers and diffusers for axial pumps, inlet and exit volutes for centrifugal pumps, and inlet and outlet cannulas, are to guide the blood into the impeller, where the blood is accelerated, and to convert the high kinetic energy into pressure after the impeller discharge, respectively. The designs of the inlet and outlet devices have an important bearing on the pump performance. Their designs are highly dependent on computational fluid dynamics (CFD) analysis, guided by intuition and experience. For inlet devices, the design objectives are to eliminate separated flow, to minimize recirculation, and to equalize the radial components of velocity. For outlet devices, the design goals are to reduce speed, to minimize energy loss, and to avoid flow separation and whirl. CFD analyses indicate the velocity field and pressure distribution. Geometrical optimization of these components has been implemented in order to improve the flow pattern. PMID:15384997

  7. Arena retrofit includes ground-source heat pump

    SciTech Connect

    Hodgson, S.F.

    1996-01-01

    The venue for Sacramento`s first professional basketball games was the {open_quotes}old Arco Arena,{close_quotes} built in 1985 just north of the downtown area and converted to offices after a large, permanent arena was constructed. In 1994, the {open_quotes}old arena{close_quotes} was acquired by a California general partnership called Del Paso Venture. To heat and cool the 3-story, 211,000-square foot structure, Del Paso has installed a ground-source heat pump system. The project is significant for the ground-source heat pump industry, because this is the first ground-source heat pump site ever designed specifically for the energy load of the building it will serve. Other projects have been calculated by rule-of-thumb. The installation and cost of the heat pump system are discussed.

  8. Biological proton pumping in an oscillating electric field.

    PubMed

    Kim, Young C; Furchtgott, Leon A; Hummer, Gerhard

    2009-12-31

    Time-dependent external perturbations provide powerful probes of the function of molecular machines. Here we study biological proton pumping in an oscillating electric field. The protein cytochrome c oxidase is the main energy transducer in aerobic life, converting chemical energy into an electric potential by pumping protons across a membrane. With the help of master-equation descriptions that recover the key thermodynamic and kinetic properties of this biological "fuel cell," we show that the proton pumping efficiency and the electronic currents in steady state depend significantly on the frequency and amplitude of the applied field, allowing us to distinguish between different microscopic mechanisms of the machine. A spectral analysis reveals dominant reaction steps consistent with an electron-gated pumping mechanism. PMID:20366348

  9. Hybrid-mode thermionic converter

    NASA Technical Reports Server (NTRS)

    Rasor, N. S.; Britt, E. J.

    1976-01-01

    Converter's collector electrode has uniform low work-function surface and operates at sufficiently low temperature to produce negligible electron emission. Emitter electrode has main region which has intermediate work-function and auxiliary region which has relatively high work-function surface.

  10. Converting accounts receivable into cash.

    PubMed

    Folk, M D; Roest, P R

    1995-09-01

    In recent years, increasing numbers of healthcare providers have converted their accounts receivable into cash through a process called securitization. This practice has gained popularity because it provides a means to raise capital necessary to healthcare organizations. Although securitization transactions can be complex, they may provide increased financial flexibility to providers as they prepare for continuing change in the healthcare industry. PMID:10145096