Formation of High-Quality μm-Order-Thick Poly-Si Films on Glass-Substrates by Flash Lamp Annealing

NASA Astrophysics Data System (ADS)

Ohdaira, Keisuke

Flash lamp annealing (FLA), millisecond-order discharge from Xe lamps, can form a few μm-thick polycrystalline Si (poly-Si) films by crystallizing precursor amorphous Si (a-Si) films prepared on low-cost substrates without serious thermal damage onto the whole glass substrates, thanks to its proper annealing duration. The FLA of a-Si films can induce lateral explosive crystallization (EC), self-catalytic crystallization driven by the release of latent heat. Periodic structures with a spacing of ˜1 μm are spontaneously left behind on and inside flash-lamp-crystallized (FLC) poly-Si films formed, when chemical-vapor-deposited (CVD) or sputtered a-Si films are used as precursor films. These microstructures result from the alternative emergence of two types of crystallization with different mechanisms during FLA: one is governed only by solid-phase nucleation (SPN) and the other includes SPN and partial liquid-phase epitaxy (LPE), resulting in the formation of grains with sizes of 10-500 nm. This rapid lateral crystallization leads to the complete preservation of abrupt dopant profiles, which is favorable for device fabrication. This particular crystallization also results in the suppression of hydrogen desorption during FLA, which realizes the formation of poly-Si films with hydrogen atoms on the order of 1021/cm3. Hydrogen atoms in poly-Si films probably act to reduce defect density, which can be on the order of 1016/cm3 after conventional furnace annealing in inert gas atmosphere. These features are suitable for the realization of high-efficiency thin-film poly-Si solar cells. Furthermore, a different type of EC can occur when using electron-beam-(EB-) evaporated a-Si films as precursor films. All the grains in the FLC poly-Si films formed stretch along lateral crystallization direction, and the length of grains is typically more than 10 μm. Based on the results of multi-pulse FLA technique, the velocity of EC is estimated to be ˜14 m/s, which corresponds to

Structural and electrical properties of Se-hyperdoped Si via ion implantation and flash lamp annealing

NASA Astrophysics Data System (ADS)

Liu, Fang; Prucnal, S.; Yuan, Ye; Heller, R.; Berencén, Y.; Böttger, R.; Rebohle, L.; Skorupa, W.; Helm, M.; Zhou, S.

2018-06-01

We report on the hyperdoping of silicon with selenium obtained by ion implantation followed by flash lamp annealing. It is shown that the degree of crystalline lattice recovery of the implanted layers and the Se substitutional fraction depend on the pulse duration and energy density of the flash. While the annealing at low energy densities leads to an incomplete recrystallization, annealing at high energy densities results in a decrease of the substitutional fraction of impurities. The electrical properties of the implanted layers are well-correlated with the structural properties resulting from different annealing processing.

Monitoring of drugs and metabolites in body fluids by capillary electrophoresis with XeHg lamp-based and laser-induced fluorescence detection.

PubMed

Caslavska, Jitka; Thormann, Wolfgang

2004-06-01

Commercial capillary electrophoresis instrumentation with XeHg lamp-based and laser induced fluorescence (LIF) detection is employed for analysis of urinary 3,4-methylenedioxymethamphetamine (MDMA, Ecstasy) and its major metabolites, urinary metabolites of acetylsalicylic acid, urinary benzoylecgonine in an immunoassay format, and albendazole sulfoxide and albendazole sulfone in plasma. For the examples studied, the data suggest that the lamp-based detector can be employed for the monitoring of pharmacological and toxicological relevant solute concentrations, and thus represents an attractive alternative to LIF detection.

A spectral radiance comparison of a noise tube and a HgXe arc lamp between 60 GHz and 600 GHz

NASA Technical Reports Server (NTRS)

Heaney, J. B.; Stewart, K. P.; Boucarut, R. A.; Moller, K. D.; Zoeller, R.

1987-01-01

The relative spectral radiance of a noise tube, model TN-167, designed for the frequency range 90-140 GHz (3.3 mm to 2.1 mm) was compared to that from a 200-watt high pressure HgXe arc lamp over the wavelength region from 0.5 to about 5 mm. A Michelson Fourier transform spectrometer and a lamellar grating instrument were used in conjunction with liquid helium-cooled bolometers of NEP 10 to the -12th to 10 to the -14th watt/(Hz) exp 1/2 to measure relative spectral radiant power. With this instrumental arrangement, the noise tube exhibited a very sharp low frequency cutoff at about 2.2/cm. The HgXe arc lamp emitted more radiant power than the noise tube in the wavelength region below 3 mm (100 GHz) down to 0.5 mm. Above 3 mm, the noise tube had a stronger output. The noise tube spectral radiance shifted to lower frequencies when the input current was lowered from 125 mA to 50 mA.

Energy and Emission Characteristics of a Short-Arc Xenon Flash Lamp Under "Saturated" Optical Brightness Conditions

NASA Astrophysics Data System (ADS)

Kamrukov, A. S.; Kireev, S. G.; Kozlov, N. P.; Shashkovskii, S. G.

2017-09-01

We present the results of a study of the electrical, energy, and spectral brightness characteristics of an experimental three-electrode high-pressure xenon flash lamp under conditions ensuring close to maximum possible spectral brightness for the xenon emission. We show that under saturated optical brightness conditions (brightness temperature in the visible region of the spectrum 30,000 K), emission of a pulsed discharge in xenon is quite different from the emission from an ideal blackbody: the maximum brightness temperatures are 24,000 K in the short-wavelength UV region and 19,000 K in the near IR range. The relative fraction of UV radiation in the emission spectrum of the lamp is >50%, which lets us consider such lamps as promising broadband sources of radiation with high spectral brightness for many important practical applications.

Investigation of the evolution of nitrogen defects in flash-lamp-annealed InGaZnO films and their effects on transistor characteristics

NASA Astrophysics Data System (ADS)

Eom, Tae-Yil; Ahn, Chee-Hong; Kang, Jun-Gu; Saad Salman, Muhammad; Lee, Sun-Young; Kim, Yong-Hoon; Lee, Hoo-Jeong; Kang, Chan-Mo; Kang, Chiwon

2018-06-01

In this study, we show the evolution of nitrogen defects during a sol–gel reaction in flash-lamp-annealed InGaZnO (IGZO) films and their effects on the device characteristics of their thin-film transistors (TFTs). The flash lamp annealing (FLA) of the IGZO TFT for 16 s helps achieve a mobility of approximately 7 cm2 V‑1 s‑1. However, further extension of the annealing time results only in drastic increases in carrier concentration and off-current. The X-ray photoelectron spectroscopy (XPS) analysis of the N 1s peak unravels the presence of oxygen-vacancy-associated nitrogen defects and their evolution with annealing time, which is possibly responsible for the increase in carrier concentration.

Influence of the chlorine concentration on the radiation efficiency of a XeCl exciplex lamp

NASA Astrophysics Data System (ADS)

Avtaeva, S. V.; Sosnin, E. A.; Saghi, B.; Panarin, V. A.; Rahmani, B.

2013-09-01

The influence of the chlorine concentration on the radiation efficiency of coaxial exciplex lamps (excilamps) excited by a dielectric barrier discharge (DBD) in binary Xe-Cl2 mixtures at pressures of 240-250 Torr is investigated experimentally and theoretically. The experiments were carried out at Cl2 concentrations in the range of 0.01-1%. The DBD characteristics were calculated in the framework of a one-dimensional hydrodynamic model at Cl2 concentrations in the range of 0.1-5%. It is found that the radiation intensities of the emission bands of Xe*2(172 nm) and XeCl* (308 nm) are comparable when the chlorine concentration in the mixture is in the range of 0.01-0.1%. In this case, in the mixture, the radiation intensity of the Xe*2 molecule rapidly decreases with increasing Cl2 concentration and, at a chlorine concentration of ≥0.2%, the radiation of the B → X band of XeCl* molecules with a peak at 308 nm dominates in the discharge radiation. The radiation efficiency of this band reaches its maximum value at chlorine concentrations in the range of 0.4-0.5%. The calculated efficiencies of DBD radiation exceed those obtained experimentally. This is due to limitations of the one-dimensional model, which assumes the discharge to be uniform in the transverse direction, whereas the actual excilamp discharge is highly inhomogeneous. The influence of the chlorine concentration on the properties of the DBD plasma in binary Xe-Cl2 mixtures is studied numerically. It is shown that an increase in the Cl2 concentration in the mixture leads to the attachment of electrons to chlorine atoms and a decrease in the electron density and discharge conductivity. As a result, the electric field and the voltage drop across the discharge gap increase, which, in turn, leads to an increase in the average electron energy and the probability of dissociation of Cl2 molecules and ionization of Xe atoms and Cl2 molecules. The total energy deposited in the discharge rises with increasing

Formation and photoluminescence of GaAs1-xNx dilute nitride achieved by N-implantation and flash lamp annealing

NASA Astrophysics Data System (ADS)

Gao, Kun; Prucnal, S.; Skorupa, W.; Helm, M.; Zhou, Shengqiang

2014-07-01

In this paper, we present the fabrication of dilute nitride semiconductor GaAs1-xNx by nitrogen-ion-implantation and flash lamp annealing (FLA). N was implanted into the GaAs wafers with atomic concentration of about ximp1 = 0.38% and ximp2 = 0.76%. The GaAs1-xNx layer is regrown on GaAs during FLA treatment in a solid phase epitaxy process. Room temperature near band-edge photoluminescence (PL) has been observed from the FLA treated GaAs1-xNx samples. According to the redshift of the near band-edge PL peak, up to 80% and 44% of the implanted N atoms have been incorporated into the lattice by FLA for ximp1 = 0.38% and ximp2 = 0.76%, respectively. Our investigation shows that ion implantation followed by ultrashort flash lamp treatment, which allows for large scale production, exhibits a promising prospect on bandgap engineering of GaAs based semiconductors.

Flash Lamp Integrating Sphere Technique for Measuring the Dynamic Reflectance of Shocked Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stevens, Gerald; La Lone, Brandon; Veeser, Lynn

2013-07-08

Accurate reflectance (R) measurements of metals undergoing shock wave compression can benefit high pressure research in several ways. For example, pressure dependent reflectance measurements can be used to deduce electronic band structure, and discrete changes with pressure or temperature may indicate the occurrence of a phase boundary. Additionally, knowledge of the wavelength dependent emissivity (1 -R, for opaque samples) of the metal surface is essential for accurate pyrometric temperature measurement because the radiance is a function of both the temperature and emissivity. We have developed a method for measuring dynamic reflectance in the visible and near IR spectral regions withmore » nanosecond response time and less than 1.5% uncertainty. The method utilizes an integrating sphere fitted with a xenon flash-lamp illumination source. Because of the integrating sphere, the measurements are insensitive to changes in surface curvature or tilt. The in-situ high brightness of the flash-lamp exceeds the sample’s thermal radiance and also enables the use of solid state detectors for recording the reflectance signals with minimal noise. Using the method, we have examined the dynamic reflectance of gallium and tin subjected to shock compression from high explosives. The results suggest significant reflectance changes across phase boundaries for both metals. We have also used the method to determine the spectral emissivity of shock compressed tin at the interface between tin and a LiF window. The results were used to perform emissivity corrections to previous pyrometry data and obtain shock temperatures of the tin/LiF interface with uncertainties of less than 2%.« less

Analysis of a four lamp flash system for calibrating multi-junction solar cells under concentrated light

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schachtner, Michael, E-mail: michael.schachtner@ise.fraunhofer.de; Prado, Marcelo Loyo; Reichmuth, S. Kasimir

2015-09-28

It has been known for a long time that the precise characterization of multi-junction solar cells demands spectrally tunable solar simulators. The calibration of innovative multi-junction solar cells for CPV applications now requires tunable solar simulators which provide high irradiation levels. This paper describes the commissioning and calibration of a flash-based four-lamp simulator to be used for the measurement of multi-junction solar cells with up to four subcells under concentrated light.

Liquid-phase explosive crystallization of electron-beam-evaporated a-Si films induced by flash lamp annealing

NASA Astrophysics Data System (ADS)

Ohdaira, Keisuke; Matsumura, Hideki

2013-01-01

We succeed in the formation of micrometer-order-thick polycrystalline silicon (poly-Si) films through the flash-lamp-induced liquid-phase explosive crystallization (EC) of precursor a-Si films prepared by electron-beam (EB) evaporation. The velocity of the explosive crystallization (vEC) is estimated to be ˜14 m/s, which is close to the velocity of the liquid-phase epitaxy (LPE) of Si at a temperature around the melting point of a-Si of 1418 K. Poly-Si films formed have micrometer-order-long grains stretched along a lateral crystallization direction, and X-ray diffraction (XRD) and electron diffraction pattern measurements reveal that grains in poly-Si films tend to have a particular orientation. These features are significantly different from our previous results: the formation of poly-Si films containing randomly-oriented 10-nm-sized fine grains formed from a-Si films prepared by catalytic chemical vapor deposition (Cat-CVD) or sputtering. One possible reason for the emergence of a different EC mode in EB-evaporated a-Si films is the suppression of solid-phase nucleation (SPN) during Flash Lamp Annealing (FLA) due to tensile stress which precursor a-Si films originally hold. Poly-Si films formed from EB-evaporated a-Si films would contribute to the realization of high-efficiency thin-film poly-Si solar cells because of large and oriented grains.

Formation of silicon nanocrystals in silicon carbide using flash lamp annealing

NASA Astrophysics Data System (ADS)

Weiss, Charlotte; Schnabel, Manuel; Prucnal, Slawomir; Hofmann, Johannes; Reichert, Andreas; Fehrenbach, Tobias; Skorupa, Wolfgang; Janz, Stefan

2016-09-01

During the formation of Si nanocrystals (Si NC) in SixC1-x layers via solid-phase crystallization, the unintended formation of nanocrystalline SiC reduces the minority carrier lifetime and therefore the performance of SixC1-x as an absorber layer in solar cells. A significant reduction in the annealing time may suppress the crystallization of the SiC matrix while maintaining the formation of Si NC. In this study, we investigated the crystallization of stoichiometric SiC and Si-rich SiC using conventional rapid thermal annealing (RTA) and nonequilibrium millisecond range flash lamp annealing (FLA). The investigated SixC1-x films were prepared by plasma-enhanced chemical vapor deposition and annealed at temperatures from 700 °C to 1100 °C for RTA and at flash energies between 34 J/cm2 and 62 J/cm2 for FLA. Grazing incidence X-ray diffraction and Fourier transformed infrared spectroscopy were conducted to investigate hydrogen effusion, Si and SiC NC growth, and SiC crystallinity. Both the Si content and the choice of the annealing process affect the crystallization behavior. It is shown that under certain conditions, FLA can be successfully utilized for the formation of Si NC in a SiC matrix, which closely resembles Si NC in a SiC matrix achieved by RTA. The samples must have excess Si, and the flash energy should not exceed 40 J/cm2 and 47 J/cm2 for Si0.63C0.37 and Si0.77C0.23 samples, respectively. Under these conditions, FLA succeeds in producing Si NC of a given size in less crystalline SiC than RTA does. This result is discussed in terms of nucleation and crystal growth using classical crystallization theory. For FLA and RTA samples, an opposite relationship between NC size and Si content was observed and attributed either to the dependence of H effusion on Si content or to the optical absorption properties of the materials, which also depend on the Si content.

High-intensity xenon plasma discharge lamp for bulk-sensitive high-resolution photoemission spectroscopy.

PubMed

Souma, S; Sato, T; Takahashi, T; Baltzer, P

2007-12-01

We have developed a highly brilliant xenon (Xe) discharge lamp operated by microwave-induced electron cyclotron resonance (ECR) for ultrahigh-resolution bulk-sensitive photoemission spectroscopy (PES). We observed at least eight strong radiation lines from neutral or singly ionized Xe atoms in the energy region of 8.4-10.7 eV. The photon flux of the strongest Xe I resonance line at 8.437 eV is comparable to that of the He Ialpha line (21.218 eV) from the He-ECR discharge lamp. Stable operation for more than 300 h is achieved by efficient air-cooling of a ceramic tube in the resonance cavity. The high bulk sensitivity and high-energy resolution of PES using the Xe lines are demonstrated for some typical materials.

ETV Report:Siemens Model H-4XE-HO Open Channel UV System

EPA Science Inventory

Verification testing of the Siemens Barrier Sunligt H-4XE-HO UV System was completed at the UV Validation and Research Center of New York (UV Center), located in Johnstown, NY. The H-4XE System utilizes 16 high-output, low-pressure lamps oriented horizontally and parallel to the...

Development and performance characteristics of flash lamp pumped Yb:YAG, Cr:Tm:Ho:YAG, Er:Tm:Ho:YLF laser sources and investigation of their potential biological applications

NASA Astrophysics Data System (ADS)

Karadimitriou, N.; Klinkenberg, B.; Papadopoulos, D. N.; Serafetinides, A. A.

2007-07-01

Laser ablation for the formation of apodized patterns on intraocular lenses, as an alternative of the conventional injection molding, has been proved to be a very promising new technique. For the precise lenses ablation, the use of suitable laser wavelength and pulse duration, resulting in a small optical penetration depth in the lens and in confinement of the energy deposition in a small volume, as well as the reduced thermal damage to the surrounding tissue, is essential. Mid-infrared laser wavelengths, at which the organic biological simulators absorption coefficient is large, meet well the above conditions. Towards the complete understanding of the intraocular lens ablation procedure and therefore the choice of the optimum laser beam characteristics for the most accurate, efficient and safe surgical application, the comparative study of various mid-infrared laser sources is of great interest. In this work we investigate the potential of the development of three different mid-infrared laser sources, namely the Yb:YAG, the Cr:Tm:Ho:YAG and the Er:Tm:Ho:YLF laser, operating at 1029 nm, 2060 nm and 2080 nm respectively and their ability in forming patterns on biomaterials. Pumping was achieved with conventional Xe flash lamps in a double elliptical pump chamber. A properly designed Pulse-Forming- Network capable of delivering energy up to 800 J, in variable lamp illumination durations is used. Several hundreds of mJoules were achieved from the Yb:YAG laser oscillator and several Joules from the Ho:YAG and Ho:YLF laser oscillators. Free running and Q-switched laser operation studies and preliminary experiments on laser and biomaterials (biopolymers and animal tissues) interactions will be reported.

Improved vacuum-UV (VUV)-initiated photomineralization of organic compounds in water with a xenon excimer flow-through photoreactor (Xe2* lamp, 172 nm) containing an axially centered ceramic oxygenator.

PubMed

Oppenländer, Thomas; Walddörfer, Carsten; Burgbacher, Jens; Kiermeier, Martin; Lachner, Klaus; Weinschrott, Helga

2005-07-01

Xenon excimer (Xe2*) lamps can be used for the oxidation and mineralization of organic compounds in aqueous solution. This vacuum-ultraviolet (VUV) photochemical method is mainly based on the photochemically initiated homolysis of water that produces hydrogen atoms and hydroxyl radicals. The efficiency of substrate oxidation and mineralization is limited markedly due to the high absorbance of water at the emission maximum of the Xe2* lamp (lambda(max)=172 nm). This photochemical condition generates an extreme heterogeneity between the irradiated volume V(irr) and the non-irradiated ("dark") bulk solution. During VUV-initiated photomineralization of organic substrates, the fast scavenging of hydrogen atoms and of carbon-centered radicals by dissolved molecular oxygen produces a permanent oxygen deficit within V(irr) and adjacent compartments. Hence, at a constant photon flux the concentration of dissolved molecular oxygen within the zones of photo and thermal radical reactions limits the rate of mineralization, i.e. the rate of TOC diminution. Thus, a simple and convenient technique is presented that overcomes this limitation by injection of molecular oxygen (or air) into the irradiated volume by use of a ceramic oxygenator (aerator). The tube oxygenator was centered axially within the xenon excimer flow-through lamp. Consequently, the oxygen or air bubbles enhanced the transfer of dissolved molecular oxygen into the VUV-irradiated volume leading to an increased rate of mineralization of organic model compounds, e.g. 1-heptanol, benzoic acid and potassium hydrogen phthalate.

Formation and photoluminescence of GaAs{sub 1−x}N{sub x} dilute nitride achieved by N-implantation and flash lamp annealing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, Kun, E-mail: k.gao@hzdr.de; Helm, M.; Technische Universität Dresden, 01062 Dresden

2014-07-07

In this paper, we present the fabrication of dilute nitride semiconductor GaAs{sub 1−x}N{sub x} by nitrogen-ion-implantation and flash lamp annealing (FLA). N was implanted into the GaAs wafers with atomic concentration of about x{sub imp1} = 0.38% and x{sub imp2} = 0.76%. The GaAs{sub 1−x}N{sub x} layer is regrown on GaAs during FLA treatment in a solid phase epitaxy process. Room temperature near band-edge photoluminescence (PL) has been observed from the FLA treated GaAs{sub 1−x}N{sub x} samples. According to the redshift of the near band-edge PL peak, up to 80% and 44% of the implanted N atoms have been incorporated into the lattice bymore » FLA for x{sub imp1} = 0.38% and x{sub imp2} = 0.76%, respectively. Our investigation shows that ion implantation followed by ultrashort flash lamp treatment, which allows for large scale production, exhibits a promising prospect on bandgap engineering of GaAs based semiconductors.« less

Flash lamp-excited time-resolved fluorescence microscope suppresses autofluorescence in water concentrates to deliver an 11-fold increase in signal-to-noise ratio.

PubMed

Connally, Russell; Veal, Duncan; Piper, James

2004-01-01

The ubiquity of naturally fluorescing components (autofluorophores) encountered in most biological samples hinders the detection and identification of labeled targets through fluorescence-based techniques. Time-resolved fluorescence (TRF) is a technique by which the effects of autofluorescence are reduced by using specific fluorescent labels with long fluorescence lifetimes (compared with autofluorophores) in conjunction with time-gated detection. A time-resolved fluorescence microscope (TRFM) is described that is based on a standard epifluorescence microscope modified by the addition of a pulsed excitation source and an image-intensified time-gateable CCD camera. The choice of pulsed excitation source for TRFM has a large impact on the price and performance of the instrument. A flash lamp with rapid discharge characteristics was selected for our instrument because of the high spectral energy in the UV region and short pulse length. However, the flash output decayed with an approximate lifetime of 18 micros and the TRFM required a long-lived lanthanide chelate label to ensure that probe fluorescence was visible after decay of the flash plasma. We synthesized a recently reported fluorescent chelate (BHHCT) and conjugated it to a monoclonal antibody directed against the waterborne parasite Giardia lamblia. For a 600-nm bandpass filter set and a gate delay of 60 micros, the TRFM provided an 11.3-fold improvement in the signal-to-noise ratio (S/N) of labeled Giardia over background. A smaller gain in an SNR of 9.69-fold was achieved with a 420-nm longpass filter set; however, the final contrast ratio between labeled cyst and background was higher (11.3 versus 8.5). Despite the decay characteristics of the light pulse, flash lamps have many practical advantages compared with optical chopper wheels and modulated lasers for applications in TRFM.

Simple luminescence detectors using a light-emitting diode or a Xe lamp, optical fiber and charge-coupled device, or photomultiplier for determining proteins in capillary electrophoresis: a critical comparison.

PubMed

Casado-Terrones, Silvia; Fernández-Sánchez, Jorge F; Segura-Carretero, Antonio; Fernández-Gutiérrez, Alberto

2007-06-01

The performance of two homemade fluorescence-induced capillary electrophoresis detectors, one based on light-emitting diode (LED) as the excitation source and a charge-coupled device (CCD) photodetector and the other based on a commercial luminescence spectrometer (Xe lamp) as the excitation source and a photomultiplier tube as a detector, were compared for the determination of fluorescent proteins R-phycoerythrin and B-phycoerythrin. Both devices use commercially available, reasonably priced optical components that can be used by nonexperts. After fine optimization of several optical and separation parameters in both devices, a zone capillary electrophoresis methodology was achieved with 50mM borate buffer (pH 8.4) and 10mM phytic acid for the determination of two phycobiliproteins. Detection limits of 0.50 and 0.64microg/ml for R-phycoerythrin and B-phycoerythrin, respectively, were achieved by using the LED-induced fluorescence capillary electrophoresis (LED-IF-CE) system, and corresponding detection limits of 2.73 and 2.16microg/ml were achieved by using the Xe lamp-IF-CE system. Analytical performance and other parameters, such as cost and potential to miniaturization, are compared for both devices.

Engineering of a highly efficient Xe₂*-excilamp (xenon excimer lamp, λmax=172 nm, η=40%) and qualitative comparison to a low-pressure mercury lamp (LP-Hg, λ=185/254 nm) for water purification.

PubMed

Al-Gharabli, Samer; Engeßer, Patrick; Gera, Diana; Klein, Sandra; Oppenländer, Thomas

2016-02-01

Excilamps are mercury-free gas-discharge sources of non-coherent VUV or UV radiation with high radiant power and a long lifetime. The most efficient excilamp that is currently available on the market is a VUV xenon excilamp system (Xe2(*)-excimer lamp, λ(max) = 172 nm) with a stated radiant efficiency η of 40% at an electrical input power P(el) of 20 W, 50 W or 100 W. In this paper, the use of this highly efficient Xe2(*)-excilamp (P(el) = 20 W) for water treatment is demonstrated using a recirculating laboratory photoreactor system with negative radiation geometry. The efficiency in the 172 nm initiated bleaching of aqueous solutions of Rhodamine B is compared to that initiated by a common low-pressure mercury (LP-Hg) lamp (185 nm, TNN 15/32). The dependence of the pseudo zero order rate constant k´ of decolorization of RhB on the flow rate and on the initial concentration of RhB was investigated. Both lamps exhibited dependences of k´ on the initial concentration of RhB, which represents a typical saturation kinetical behavior. The saturation kinetics was very prominent in the case of the Xe2(*)-excilamp. Also, the Xe2(*)-excilamp treatment exhibited a significant influence on the flow rate of the RhB aqueous solution, which was not the case during the LP-Hg lamp initiated bleaching of RhB. The results of this paper demonstrate that Xe2(*)-excilamps can be used for VUV-initiated water purification. However, to reach the maximum efficacy of the Xe2(*)-excilamp for photo-initiated water purification further engineering optimization of the photoreactor concept is necessary. Copyright © 2015 Elsevier Ltd. All rights reserved.

Post-Flash Validation of the new ACS/WFC Subarrays

NASA Astrophysics Data System (ADS)

Bellini, A.; Grogin, N. A.; Lim, P. L.; Golimowski, D.

2017-05-01

We made use of the new ACS/WFC subarray images of CAL-14410, taken taken with a large range of flash exposure times (0.1-30 seconds), to probe the temporal stability of the reference flash file and to validate the current post-flash correction pipeline of CALACS and ACS DESTRIPE PLUS on the new subarray modes. No statistically-significant deviations are found between the new post-flashed subarray exposures and the flash reference file, indicating that the LED lamp used to post-flash ACS images has been stable over several years. The current calibration pipelines (both CALACS and ACS DESTRIPE PLUS can be successfully used with the new subarray modes.

Recent advance to 3 × 10(-5) rad near diffraction-limited beam divergence of dye laser with transverse-discharge flash-lamp pumping.

PubMed

Trusov, K K

1994-02-20

A new experimental setup of a Rhodamine 6G dye laser with a transverse-discharge flash-lamp-pumping system is presented. It differs from a previous setup [Sov. J. Quantum Electron. 16, 468-471 (1989)] in that it has a larger laser beam aperture (32 mm) and higher pumping energy (1 kJ), which made it possible to test the scalability and reach near diffraction-limited laser beam divergence of 3 × 10(-5) rad FWHM at beam energy 1.4 J. The effect of spectral dispersion in the active medium and of other optical elements on the beam divergence is also discussed.

Effect of starting point formation on the crystallization of amorphous silicon films by flash lamp annealing

NASA Astrophysics Data System (ADS)

Sato, Daiki; Ohdaira, Keisuke

2018-04-01

We succeed in the crystallization of hydrogenated amorphous silicon (a-Si:H) films by flash lamp annealing (FLA) at a low fluence by intentionally creating starting points for the trigger of explosive crystallization (EC). We confirm that a partly thick a-Si part can induce the crystallization of a-Si films. A periodic wavy structure is observed on the surface of polycrystalline silicon (poly-Si) on and near the thick parts, which is a clear indication of the emergence of EC. Creating partly thick a-Si parts can thus be effective for the control of the starting point of crystallization by FLA and can realize the crystallization of a-Si with high reproducibility. We also compare the effects of creating thick parts at the center and along the edge of the substrates, and a thick part along the edge of the substrates leads to the initiation of crystallization at a lower fluence.

Formation of shallow boron emitters in crystalline silicon using flash lamp annealing: Role of excess silicon interstitials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riise, Heine Nygard, E-mail: h.n.riise@fys.uio.no; Azarov, Alexander; Svensson, Bengt G.

2015-07-13

Shallow, Boron (B)-doped p{sup +} emitters have been realized using spin-on deposition and Flash Lamp Annealing (FLA) to diffuse B into monocrystalline float zone Silicon (Si). The emitters extend between 50 and 140 nm in depth below the surface, have peak concentrations between 9 × 10{sup 19 }cm{sup –3} and 3 × 10{sup 20 }cm{sup –3}, and exhibit sheet resistances between 70 and 3000 Ω/□. An exceptionally large increase in B diffusion occurs for FLA energy densities exceeding ∼93 J/cm{sup 2} irrespective of 10 or 20 ms pulse duration. The effect is attributed to enhanced diffusion of B caused by Si interstitial injection following a thermally activated reaction betweenmore » the spin-on diffusant film and the silicon wafer.« less

Method and apparatus for implementing material thermal property measurement by flash thermal imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Jiangang

A method and apparatus are provided for implementing measurement of material thermal properties including measurement of thermal effusivity of a coating and/or film or a bulk material of uniform property. The test apparatus includes an infrared camera, a data acquisition and processing computer coupled to the infrared camera for acquiring and processing thermal image data, a flash lamp providing an input of heat onto the surface of a two-layer sample with an enhanced optical filter covering the flash lamp attenuating an entire infrared wavelength range with a series of thermal images is taken of the surface of the two-layer sample.

LASER APPLICATIONS AND OTHER TOPICS IN QUANTUM ELECTRONICS: On the possibility of pumping Xe2* lasers and VUV lamps in the afterglow of a background-electron multiplication wave

NASA Astrophysics Data System (ADS)

Boichenko, Aleksandr M.; Yakovlenko, Sergei I.

2006-12-01

It was shown earlier that the ionisation propagation in a gas at about the atmospheric pressure may proceed due to the multiplication of the existing electrons with a low background density rather than the transfer of electrons or photons. We consider the feasibility of using the plasma produced in the afterglow of this background-electron multiplication wave for pumping plasma lasers (in particular, Xe2* xenon excimer lasers) as well as excilamps. Simulations show that it is possible to achieve the laser effect at λapprox172 nm as well as to substantially improve the peak specific power of the spontaneous radiation of xenon lamps.

Modeling of a Ne/Xe dielectric barrier discharge excilamp for improvement of VUV radiation production

NASA Astrophysics Data System (ADS)

Khodja, K.; Belasri, A.; Loukil, H.

2017-08-01

This work is devoted to excimer lamp efficiency optimization by using a homogenous discharge model of a dielectric barrier discharge in a Ne-Xe mixture. The model includes the plasma chemistry, electrical circuit, and Boltzmann equation. In this paper, we are particularly interested in the electrical and kinetic properties and light output generated by the DBD. Xenon is chosen for its high luminescence in the range of vacuum UV radiation around 173 nm. Our study is motivated by interest in this type of discharge in many industrial applications, including the achievement of high light output lamps. In this work, we used an applied sinusoidal voltage, frequency, gas pressure, and concentration in the ranges of 2-8 kV, 10-200 kHz, 100-800 Torr, and 10-50%, respectively. The analyzed results concern the voltage V p across the gap, the dielectric voltage V d, the discharge current I, and the particles densities. We also investigated the effect of the electric parameters and xenon concentration on the lamp efficiency. This investigation will allow one to find out the appropriate parameters for Ne/Xe DBD excilamps to improve their efficiency.

Photochemical removal of NO(2) by using 172-nm Xe(2) excimer lamp in N(2) or air at atmospheric pressure.

PubMed

Tsuji, Masaharu; Kawahara, Masashi; Noda, Kenji; Senda, Makoto; Sako, Hiroshi; Kamo, Naohiro; Kawahara, Takashi; Kamarudin, Khairul Sozana Nor

2009-03-15

Photochemical removal of NO(2) in N(2) or air (5-20% O(2)) mixtures was studied by using 172-nm Xe(2) excimer lamps to develop a new simple photochemical aftertreatment technique of NO(2) in air at atmospheric pressure without using any catalysts. When a high power lamp (300 mW/cm(2)) was used, the conversion of NO(2) (200-1000 ppm) to N(2) and O(2) in N(2) was >93% after 1 min irradiation, whereas that to N(2)O(5), HNO(3), N(2), and O(2) in air (10% O(2)) was 100% after 5s irradiation in a batch system. In a flow system, about 92% of NO(2) (200 ppm) in N(2) was converted to N(2) and O(2), whereas NO(2) (200-400 ppm) in air (20% O(2)) could be completely converted to N(2)O(5), HNO(3), N(2), and O(2) at a flow rate of 1l/min. It was found that NO could also be decomposed to N(2) and O(2) under 172-nm irradiation, though the removal rate is slower than that of NO(2) by a factor of 3.8. A simple model analysis assuming a consecutive reaction NO(2)-->NO-->N+O indicated that 86% of NO(2) is decomposed directly into N+O(2) and the rest is dissociated into NO+O under 172-nm irradiation. These results led us to conclude that the present technique is a new promising catalyst-free photochemical aftertreatment method of NO(2) in N(2) and air in a flow system.

Origin and enhancement of the 1.3 μm luminescence from GaAs treated by ion-implantation and flash lamp annealing

NASA Astrophysics Data System (ADS)

Gao, Kun; Prucnal, S.; Skorupa, W.; Helm, M.; Zhou, Shengqiang

2013-09-01

GaAs and GaAs based materials have outstanding optoelectronic properties and are widely used as light emitting media in devices. Many approaches have been applied to GaAs to generate luminescence at 0.88, 1.30, and 1.55 μm which are transmission windows of optical fibers. In this paper, we present the photoluminescence at 1.30 μm from deep level defects in GaAs treated by ion-implantation and flash lamp annealing (FLA). Such emission, which exhibits superior temperature stability, can be obtained from FLA treated virgin GaAs as well as doped GaAs. Indium-doping in GaAs can greatly enhance the luminescence. By photoluminescence, Raman measurements, and positron annihilation spectroscopy, we conclude that the origin of the 1.30 μm emission is from transitions between the VAs-donor and X-acceptor pairs.

Primordial Terrestrial Xe from the Viewpoint of CFF-Xe

NASA Astrophysics Data System (ADS)

Meshik, A. P.; Shukolyukov, Yu. A.; Jessberger, E. K.

1995-09-01

We have already reported [7, 23] on the non-linear isotope mass-fractionation of fission Xe by migration of the precursors I, Te, Sn, and Sb and simultaneous fission of heavy nuclei. Xe with anomalous isotopic pattern was found in a number of meteorites and terrestrial materials and was named CFF-Xe (Chemically Fractionated Fission Xe). It is characterized by an up eightfold ^132Xe and ^131Xe excesses coupled with smaller ^134Xe and ^129Xe excesses. The present work is aimed to estimate the role of CFF-Xe in the terrestrial lithosphere and specifically deals with the problem of the isotopic composition of primordial terrestrial Xe. Due to variations of the migration conditions the isotopic structure of CFF-Xe is not well established and is even not reproducible in the same rock [2]. Nevertheless, we have tried to estimate the composition of CFF-Xe by investigating all available isotopic data of Xe of presumable mantle origin. This is Xe in MORB [29, 1, 12] and ocean island glasses [1, 28], in diamonds [17], in volcanic rocks [29, 8, 9, 21], in volcanic glasses from pillow basalts [16, 6], continental igneous rocks [1, 24, 10, 22], carbonatites and granitoids [1] as well as Xe in natural gases [3, 24, 11, 4, 15]. All data are plotted Fig. 1 where we also suggest end members of the observed scattering. Optimized slopes of CFF-lines are shown as well as the position of the initial points which we regard as primordial terrestrial Xe (Xe0). The isotopic composition of CFF-Xe and Xe0 are given in Tab. 1. The abundances of ^124Xe and ^126Xe in mantle derived samples are very uncertain, but since ^128Xe/^130Xe in Xea and Xe0 is very similar we propose the same ^124Xe/^130Xe and ^126Xe/^130Xe ratios for both Xea and Xe0. If so, AVCC-Xe is simply Xe0 with an admixture of L-Xe, and atmospheric xenon Xea consists of Xe0, CFF-Xe and a small amount of fission Xe (92.5%Xe0 + 5.3%CFF-Xe + 2.2%XeF). Thus, a number of old problems in xenology are removed. The hypothetic components U-Xe

Flash photolysis of rhodopsin in the cat retina

PubMed Central

1981-01-01

The bleaching of rhodopsin by short-duration flashes of a xenon discharge lamp was studied in vivo in the cat retina with the aid of a rapid, spectral-scan fundus reflectometer. Difference spectra recorded over a broad range of intensities showed that the bleaching efficacy of high-intensity flashes was less than that of longer duration, steady lights delivering the same amount of energy. Both the empirical results and those derived from a theoretical analysis of flash photolysis indicate that, under the conditions of these experiments, the upper limit of the flash bleaching of rhodopsin in cat is approximately 90%. Although the fact that a full bleach could not be attained is attributable to photoreversal, i.e., the photic regeneration of rhodopsin from its light-sensitive intermediates, the 90% limit is considerably higher than the 50% (or lower) value obtained under other experimental circumstances. Thus, it appears that the duration (approximately 1 ms) and spectral composition of the flash, coupled with the kinetic parameters of the thermal and photic reactions in the cat retina, reduce the light-induced regeneration of rhodopsin to approximately 10%. PMID:7252476

Measuring and Estimating Normalized Contrast in Infrared Flash Thermography

NASA Technical Reports Server (NTRS)

Koshti, Ajay M.

2013-01-01

Infrared flash thermography (IRFT) is used to detect void-like flaws in a test object. The IRFT technique involves heating up the part surface using a flash of flash lamps. The post-flash evolution of the part surface temperature is sensed by an IR camera in terms of pixel intensity of image pixels. The IR technique involves recording of the IR video image data and analysis of the data using the normalized pixel intensity and temperature contrast analysis method for characterization of void-like flaws for depth and width. This work introduces a new definition of the normalized IR pixel intensity contrast and normalized surface temperature contrast. A procedure is provided to compute the pixel intensity contrast from the camera pixel intensity evolution data. The pixel intensity contrast and the corresponding surface temperature contrast differ but are related. This work provides a method to estimate the temperature evolution and the normalized temperature contrast from the measured pixel intensity evolution data and some additional measurements during data acquisition.

Investigation of 2.1-micron lasing properties of Ho:Tm:Cr:YAG crystals under flash-lamp pumping at various operating conditions

NASA Technical Reports Server (NTRS)

Kim, Kyong H.; Choi, Young S.; Barnes, Norman P.; Hess, Robert V.; Bair, Clayton H.; Brockman, Philip

1993-01-01

Flash-lamp-pumped normal-mode and Q-switched 2.1-micron laser operations of Ho:Tm:Cr:YAG crystals have been evaluated under a wide variety of experimental conditions in order to determine an optimum lasing condition and to characterize the laser outputs. Q-switched laser-output energies equal to, or in some cases exceeding the normal-mode laser energies, were obtained in the form of a strong single spike through an optimization of the opening time of a lithium niobate Q switch. The increase of the normal-mode laser slope efficiency was observed with the increase of the Tm concentration from 2.5 to 4.5 at. pct at operating temperatures from 120 K to near room temperature. Laser transitions were observed only at 2.098 and 2.091 microns under various conditions. The 2.091-micron laser transition appeared to be dominant at high-temperature operations with low-reflective-output couplers.

Photochemically induced deposition of protective alumina coatings onto UV emitting phosphors for Xe excimer discharge lamps

DOE Office of Scientific and Technical Information (OSTI.GOV)

Broxtermann, Mike, E-mail: mike.b@fh-muenster.de; Jüstel, Thomas, E-mail: tj@fh-muenster.de

2016-08-15

Highlights: • A UV-reactor for the pH induced precipitation of inorganic material is described. • The photolysis of Azide (N{sub 3}{sup −}) leads to a steady pH increase used for precipitation. • A UV induced Al(OH){sub 3} precipitation is used to craft Al{sub 2}O{sub 3} coatings onto YPO{sub 4}:Bi. • The influence of Al{sub 2}O{sub 3} coated onto YPO{sub 4}:Bi with different thicknesses is discussed. • SEM, VUV-spectroscopy and ESA measurements were performed on Al{sub 2}O{sub 3} coated samples. - Abstract: This work concerns the particle coating of the UV-C emitting phosphor YPO{sub 4}:Bi, targeting a stability enhancement of themore » phosphor material for Xe excimer lamp operation. To this end, the material is coated by the wide band gap material Al{sub 2}O{sub 3}. In order to obtain a thin and homogeneous coating layer, a novel process based on the photochemical cleavage of NaN{sub 3} in water was developed. This results in a slow and continuous enhancement of the pH value due to ongoing NaOH formation, which results in the precipitation of Al(OH){sub 3} from an Al{sub 2}(SO{sub 4}){sub 3} {sub ×} 18H{sub 2}O solution. It turned out that the obtained particle coatings are of much better quality, i.e. homogeneity, compared to coatings made from a wet-chemical homogeneous precipitation process. The morphology and electrochemical properties of Al{sub 2}O{sub 3} coated YPO{sub 4}:Bi are discussed on the basis of optical spectroscopy, ESA measurements, and SEM/EDX investigations.« less

124Xe(n,γ)125Xe and 124Xe(n,2n)123Xe measurements for National Ignition Facility

NASA Astrophysics Data System (ADS)

Bhike, Megha; Ludin, Nurin; Tornow, Werner

2015-05-01

The cross section for the 124Xe(n,γ)125Xe reaction has been measured for the first time for neutron energies above 100 keV. In addition, the 124Xe(n,2n)123Xe reaction has been studied between threshold and 14.8 MeV. The results of these measurements provide sensitive diagnostic tools for investigating properties of the inertial confinement fusion plasma in Deuterium-Tritium (DT) capsules at the National Ignition Facility (NIF) located at Lawrence Livermore National Laboratory.

New multichannel kinetic spectrophotometer-fluorimeter with pulsed measuring beam for photosynthesis research.

PubMed

Bína, David; Litvín, Radek; Vácha, Frantisek; Siffel, Pavel

2006-06-01

A multichannel kinetic spectrophotometer-fluorimeter with pulsed measuring beam and differential optics has been constructed for measurements of light-induced absorbance and fluorescence yield changes in isolated chlorophyll-proteins, thylakoids and intact cells including algae and photosynthetic bacteria. The measuring beam, provided by a short (2 micros) pulse from a xenon flash lamp, is divided into a sample and reference channel by a broad band beam splitter. The spectrum in each channel is analyzed separately by a photodiode array. The use of flash measuring beam and differential detection yields high signal-to-noise ratio (noise level of 2 x 10(-4) in absorbance units per single flash) with negligible actinic effect. The instrument covers a spectral range between 300 and 1050 nm with a spectral resolution of 2.1, 6.4 or 12.8 nm dependent on the type of grating used. The optical design of the instrument enables measuring of the difference spectra during an actinic irradiation of samples with continuous light and/or saturation flashes. The time resolution of the spectrophotometer is limited by the length of Xe flash lamp pulses to 2 micros.

Ti12Xe: A twelve-coordinated Xe-containing molecule

NASA Astrophysics Data System (ADS)

Miao, Junjian; Xu, Wenwu; Zhu, Beien; Gao, Yi

2017-08-01

A twelve-coordinated Xe-containing molecule Ti12Xe has been predicted by DFT calculations with quasi-icosahedral symmetry. Structural and NBO analyses show the chemical bonding exists between the central Xe atom and peripheral Ti atoms, which leads to the high stability of the molecule to a considerable degree. First principle molecular dynamics simulations further reveal the particularly high thermal stability of Ti12Xe up to 1500 K. This unique species may disclose new physics and chemistry of xenon element and stir interest in the Xe-transition metal cluster physics and chemistry.

Development of a Self Aligned CMOS Process for Flash Lamp Annealed Polycrystalline Silicon TFTs

NASA Astrophysics Data System (ADS)

Bischoff, Paul

The emerging active matrix liquid crystal (AMLCD) display market requires a high performing semiconductor material to meet rising standards of operation. Currently amorphous silicon (a-Si) dominates the market but it does not have the required mobility for it to be used in AMLCD manufacturing. Other materials have been developed including crystallizing a-Si into poly-silicon. A new approach to crystallization through the use of flash lamp annealing (FLA) decreases manufacturing time and greatly improves carrier mobility. Previous work on FLA silicon for the use in CMOS transistors revealed significant lateral dopant diffusion into the channel greatly increasing the minimum channel length required for a working device. This was further confounded by the gate overlap due to misalignment during lithography patterning steps. Through the use of furnace dopant activation instead of FLA dopant activation and a self aligned gate the minimum size transistor can be greatly reduced. A new lithography mask and process flow were developed for the furnace annealing and self aligned gate. Fabrication of the self aligned devices resulted in oxidation of the Molybdenum self aligned gate. Further development is needed to successfully manufacture these devices. Non-self aligned transistors were made simultaneously with self aligned devices and used the furnace activation. These devices showed an increase in sheet resistance from 250 O to 800 O and lower mobility from 380 to 40.2 V/cm2s. The lower mobility can be contributed to an increase in implanted trap density indicating furnace annealing is an inferior activation method over FLA. The minimum transistor size however was reduced from 20 to 5 mum. With improvements in the self aligned process high performing small devices can be manufactured.

Liquid phase epitaxy of binary III–V nanocrystals in thin Si layers triggered by ion implantation and flash lamp annealing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wutzler, Rene, E-mail: r.wutzler@hzdr.de; Rebohle, Lars; Prucnal, Slawomir

2015-05-07

The integration of III–V compound semiconductors in Si is a crucial step towards faster and smaller devices in future technologies. In this work, we investigate the formation process of III–V compound semiconductor nanocrystals, namely, GaAs, GaSb, and InP, by ion implantation and sub-second flash lamp annealing in a SiO{sub 2}/Si/SiO{sub 2} layer stack on Si grown by plasma-enhanced chemical vapor deposition. Raman spectroscopy, Rutherford Backscattering spectrometry, and transmission electron microscopy were performed to identify the structural and optical properties of these structures. Raman spectra of the nanocomposites show typical phonon modes of the compound semiconductors. The formation process of themore » III–V compounds is found to be based on liquid phase epitaxy, and the model is extended to the case of an amorphous matrix without an epitaxial template from a Si substrate. It is shown that the particular segregation and diffusion coefficients of the implanted group-III and group-V ions in molten Si significantly determine the final appearance of the nanostructure and thus their suitability for potential applications.« less

Hydrodynamic predictions for 5.44 TeV Xe+Xe collisions

NASA Astrophysics Data System (ADS)

Giacalone, Giuliano; Noronha-Hostler, Jacquelyn; Luzum, Matthew; Ollitrault, Jean-Yves

2018-03-01

We argue that relativistic hydrodynamics is able to make robust predictions for soft particle production in Xe+Xe collisions at the CERN Large Hadron Collider (LHC). The change of system size from Pb+Pb to Xe+Xe provides a unique opportunity to test the scaling laws inherent to fluid dynamics. Using event-by-event hydrodynamic simulations, we make quantitative predictions for several observables: mean transverse momentum, anisotropic flow coefficients, and their fluctuations. Results are shown as a function of collision centrality.

Inner-shell photoionization and core-hole decay of Xe and XeF2.

PubMed

Southworth, Stephen H; Wehlitz, Ralf; Picón, Antonio; Lehmann, C Stefan; Cheng, Lan; Stanton, John F

2015-06-14

Photoionization cross sections and partial ion yields of Xe and XeF2 from Xe 3d(5/2), Xe 3d(3/2), and F 1s subshells in the 660-740 eV range are compared to explore effects of the F ligands. The Xe 3d-ϵf continuum shape resonances dominate the photoionization cross sections of both the atom and molecule, but prominent resonances appear in the XeF2 cross section due to nominal excitation of Xe 3d and F 1s electrons to the lowest unoccupied molecular orbital (LUMO), a delocalized anti-bonding MO. Comparisons of the ion products from the atom and molecule following Xe 3d photoionization show that the charge-state distribution of Xe ions is shifted to lower charge states in the molecule along with production of energetic F(+) and F(2+) ions. This suggests that, in decay of a Xe 3d core hole, charge is redistributed to the F ligands and the system dissociates due to Coulomb repulsion. The ion products from excitation of the F 1s-LUMO resonance are different and show strong increases in the yields of Xe(+) and F(+) ions. The subshell ionization thresholds, the LUMO resonance energies, and their oscillator strengths are calculated by relativistic coupled-cluster methods and agree well with measurements.

Inner-shell photoionization and core-hole decay of Xe and XeF 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Southworth, Stephen H.; Wehlitz, Ralf; Picón, Antonio

2015-06-14

Photoionization cross sections and partial ion yields of Xe and XeF2 from Xe 3d5/2, Xe 3d3/2, and F 1s subshells in the 660–740 eV range are compared to explore effects of the F ligands. The Xe 3d-ϵf continuum shape resonances dominate the photoionization cross sections of both the atom and molecule, but prominent resonances appear in the XeF2 cross section due to nominal excitation of Xe 3d and F 1s electrons to the lowest unoccupied molecular orbital (LUMO), a delocalized anti-bonding MO. Comparisons of the ion products from the atom and molecule following Xe 3d photoionization show that the charge-statemore » distribution of Xe ions is shifted to lower charge states in the molecule along with production of energetic F+ and F2+ ions. This suggests that, in decay of a Xe 3d core hole, charge is redistributed to the F ligands and the system dissociates due to Coulomb repulsion. The ion products from excitation of the F 1s-LUMO resonance are different and show strong increases in the yields of Xe+ and F+ ions. The subshell ionization thresholds, the LUMO resonance energies, and their oscillator strengths are calculated by relativistic coupled-cluster methods and agree well with measurements.« less

Flash Diffusivity Technique Applied to Individual Fibers

NASA Technical Reports Server (NTRS)

Mayeaux, Brian; Yowell, Leonard; Wang, Hsin

2007-01-01

A variant of the flash diffusivity technique has been devised for determining the thermal diffusivities, and thus the thermal conductivities, of individual aligned fibers. The technique is intended especially for application to nanocomposite fibers, made from narrower fibers of polyphenylene benzobisthiazole (PBZT) and carbon nanotubes. These highly aligned nanocomposite fibers could exploit the high thermal conductivities of carbon nanotubes for thermal-management applications. In the flash diffusivity technique as practiced heretofore, one or more heat pulse(s) is (are) applied to the front face of a plate or disk material specimen and the resulting time-varying temperature on the rear face is measured. Usually, the heat pulse is generated by use of a xenon flash lamp, and the variation of temperature on the rear face is measured by use of an infrared detector. The flash energy is made large enough to produce a usefully high temperature rise on the rear face, but not so large as to significantly alter the specimen material. Once the measurement has been completed, the thermal diffusivity of the specimen is computed from the thickness of the specimen and the time dependence of the temperature variation on the rear face. Heretofore, the infrared detector used in the flash diffusivity technique has been a single-point detector, which responds to a spatial average of the thermal radiation from the rear specimen surface. Such a detector cannot distinguish among regions of differing diffusivity within the specimen. Moreover, two basic assumptions of the thermaldiffusivity technique as practiced heretofore are that the specimen is homogeneous and that heat flows one-dimensionally from the front to the rear face. These assumptions are not valid for an inhomogeneous (composite) material.

Comprehensive sets of 124Xe(n ,γ )125Xe and 124Xe(n ,2 n )123Xe cross-section data for assessment of inertial-confinement deuterium-tritium fusion plasma

NASA Astrophysics Data System (ADS)

Bhike, Megha; Fallin, B.; Gooden, M. E.; Ludin, N.; Tornow, W.

2015-01-01

Measurements of the neutron radiative-capture cross section of 124Xe have been performed for the first time for neutron energies above 100 keV. In addition, data for the 124Xe(n ,2 n )123Xe reaction cross section have been obtained from threshold to 14.8 MeV to cover the entire energy range of interest, while previous data existed only at around 14 MeV. The results of these measurements provide the basis for an alternative and sensitive diagnostic tool for investigating properties of the inertial confinement fusion plasma in deuterium-tritium (DT) capsules at the National Ignition Facility located at Lawrence Livermore National Laboratory. Here, areal density ρ R (density × radius) of the fuel, burn asymmetry, and fuel-ablator mix are of special interest. The 124Xe(n ,γ )125Xe reaction probes the down-scattered neutrons, while the 124Xe(n ,2 n )123Xe reaction provides a measure of the 14 MeV direct neutrons.

Hg-Xe exciplex formation in mixed Xe/Ar matrices: molecular dynamics and luminescence study.

PubMed

Lozada-García, Rolando; Rojas-Lorenzo, Germán; Crépin, Claudine; Ryan, Maryanne; McCaffrey, John G

2015-03-19

Luminescence of Hg((3)P1) atoms trapped in mixed Ar/Xe matrices containing a small amount of Xe is reported. Broad emission bands, strongly red-shifted from absorption are recorded which are assigned to strong complexes formed between the excited mercury Hg* and xenon atoms. Molecular dynamics calculations are performed on simulated Xe/Ar samples doped with Hg to follow the behavior of Hg* in the mixed rare gas matrices leading to exciplex formation. The role of Xe atoms in the first solvation shell (SS1) around Hg was investigated in detail, revealing the formation of two kinds of triatomic exciplexes; namely, Xe-Hg*-Xe and Ar-Hg*-Xe. The first species exists only when two xenon atoms are present in SS1 with specific geometries allowing the formation of a linear or quasi-linear exciplex. In the other geometries, or in the presence of only one Xe in SS1, a linear Ar-Hg*-Xe exciplex is formed. The two kinds of exciplexes have different emission bands, the most red-shifted being that involving two Xe atoms, whose emission is very close to that observed in pure Xe matrices. Simulations give a direct access to the analysis of the experimental absorption, emission, and excitation spectra, together with the dynamics of exciplexes formation.

Inner-shell photoionization and core-hole decay of Xe and XeF{sub 2}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Southworth, Stephen H.; Picón, Antonio; Lehmann, C. Stefan

2015-06-14

Photoionization cross sections and partial ion yields of Xe and XeF{sub 2} from Xe 3d{sub 5/2}, Xe 3d{sub 3/2}, and F 1s subshells in the 660–740 eV range are compared to explore effects of the F ligands. The Xe 3d-ϵf continuum shape resonances dominate the photoionization cross sections of both the atom and molecule, but prominent resonances appear in the XeF{sub 2} cross section due to nominal excitation of Xe 3d and F 1s electrons to the lowest unoccupied molecular orbital (LUMO), a delocalized anti-bonding MO. Comparisons of the ion products from the atom and molecule following Xe 3d photoionizationmore » show that the charge-state distribution of Xe ions is shifted to lower charge states in the molecule along with production of energetic F{sup +} and F{sup 2+} ions. This suggests that, in decay of a Xe 3d core hole, charge is redistributed to the F ligands and the system dissociates due to Coulomb repulsion. The ion products from excitation of the F 1s-LUMO resonance are different and show strong increases in the yields of Xe{sup +} and F{sup +} ions. The subshell ionization thresholds, the LUMO resonance energies, and their oscillator strengths are calculated by relativistic coupled-cluster methods and agree well with measurements.« less

49 CFR 393.24 - Requirements for head lamps, auxiliary driving lamps and front fog lamps.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 5 2012-10-01 2012-10-01 false Requirements for head lamps, auxiliary driving lamps and front fog lamps. 393.24 Section 393.24 Transportation Other Regulations Relating to... MOTOR CARRIER SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Lamps, Reflective...

49 CFR 393.24 - Requirements for head lamps, auxiliary driving lamps and front fog lamps.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 5 2014-10-01 2014-10-01 false Requirements for head lamps, auxiliary driving lamps and front fog lamps. 393.24 Section 393.24 Transportation Other Regulations Relating to... MOTOR CARRIER SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Lamps, Reflective...

49 CFR 393.24 - Requirements for head lamps, auxiliary driving lamps and front fog lamps.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 5 2013-10-01 2013-10-01 false Requirements for head lamps, auxiliary driving lamps and front fog lamps. 393.24 Section 393.24 Transportation Other Regulations Relating to... MOTOR CARRIER SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Lamps, Reflective...

Photoproduction of light vector mesons in Xe-Xe ultraperipheral collisions at the LHC and the nuclear density of Xe-129

NASA Astrophysics Data System (ADS)

Guzey, V.; Kryshen, E.; Zhalov, M.

2018-07-01

We make predictions for cross sections of ρ and ϕ vector meson photoproduction in ultraperipheral Xe-Xe collisions at √{sNN } = 5.44TeV. Analyzing the momentum transfer distribution of ρ mesons in this process, we explore the feasibility of extracting the nuclear density of 129Xe, which is needed in searches for dark matter with Xenon-based detectors.

Adsorption and excess fission Xe - Adsorption of Xe on vacuum crushed minerals

NASA Technical Reports Server (NTRS)

Bernatowicz, T. J.; Kramer, F. E.; Podosek, F. A.; Honda, M.

1982-01-01

It is hypothesized that adsorption is not likely to provide a sufficiently precise mechanism for the concentration of excess fission Xe in the entire lunar regolith, in view of laboratory analogs of the lunar soil and calculations of the residence times of noble gases in the present day regolith. Lunar cold trap and episodic degassing models are difficult to reconcile, however, with the generality of excess fission Xe in all gas-rich highland breccias. It is concluded that the high Xe concentration in such highland breccias is not the result of Xe adsorption prior to the trapping of this component.

I-Xe systematics in LL chondrites

NASA Technical Reports Server (NTRS)

Bernatowicz, T. J.; Podosek, F. A.; Swindle, T. D.; Honda, M.

1988-01-01

A stepwise heating analysis of Ar and Xe data from five neutron-irradiated whole rock LL chondrites (Soko Banja, Alta Ameen, Tuxtuac, Guidder, and Olivenza) is presented, emphasizing the complicated thermal history of ordinary chondrites. None of the present meteorites show a well-defined (Ar-40)-(Ar-39) apparent age plateau comprised of more than two release fractions. Most of the samples are found to yield well-defined high-temperature correlations between Xe-129/Xe-130 and Xe-128/Xe-130, and thus determinations of I-129/I-127 and Xe-129/Xe-130 at the time of isotopic closure for Xe. As in the case of other ordinary chondrites, the I-Xe systematics for LL chondrites correlate neither with a metamorphic grade nor with chronologies based opon other methods.

Xe-129 - Xe-128 and Ar-40 - Ar-39 chronology of two Antarctic enstatite meteorites

NASA Technical Reports Server (NTRS)

Honda, M.; Bernatowicz, T. J.; Podosek, F. A.

1983-01-01

Xe-129 - Xe-128 and Ar-40 - Ar-39 analyses has been performed on two Antarctic enstatite meteorites, the chondrite Y-691 and the aubrite (enstatite achondrite) ALH-78113. Both meteorites have complex Ar-40 - Ar-39 release patterns to which no unambiguous age assignment is possible. Both give apparently satisfactory Xe-129 - Xe-128 correlations corresponding to unusual ages. The I-Xe age of the chondrite Y-691 is 16 Ma after Bjurbole, not unusual for chondrites in general but 10 Ma later than previously known ages for enstatite chondrites. The I-Xe age of the aubrite ALH-78113 is 210 Ma after Bjurbole, the latest age (rather than a limit) so far observed by the I-Xe technique, but this age assignment must be considered tentative because of the possibility that it is significantly influenced by terrestrial I contamination.

49 CFR 393.24 - Requirements for head lamps, auxiliary driving lamps and front fog lamps.

Code of Federal Regulations, 2010 CFR

2010-10-01

... this paragraph. (b) Auxiliary driving lamps and front fog lamps. Commercial motor vehicles may be... Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Lamps, Reflective...

Time-dependent characteristics of the dielectric barrier discharge in Xe-Cl2 mixture and kinetics of the XeCl∗ molecules

NASA Astrophysics Data System (ADS)

Avtaeva, Svetlana

2014-04-01

Time-dependent characteristics of the dielectric barrier discharge in Xe-Cl2 mixture at chlorine concentration of 0.5% and kinetic processes governing the generation of XeCl∗ molecules are studied using the 1D fluid model. It is shown that at low voltage amplitude (5 kV) a one-peak mode of the discharge is observed and at high voltage amplitude (7 kV) a two-peak mode of the discharge appears. The radiation power of the XeCl∗ band increases with amplitude of the supply voltage. It is demonstrated that the harpoon reaction Xe∗ + Cl2 → XeCl∗ + Cl provides the greatest contribution into generation of XeCl∗ exciplex molecules during short current pulses and the ion-ion recombination Xe+ 2 + Cl- → XeCl* + Xe provides the greatest contribution during afterglow. Quenching of XeCl∗ molecules is a result of the radiative decay XeCl∗ → Xe + Cl + hv (308 nm). During current spike the great contribution into quenching of XeCl∗ provides also the dissociative ionization e + XeCl∗ → Xe+ + Cl + 2e.

The effect of millisecond flash lamp annealing on electrical and structural properties of ZnO:Al/Si structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lindberg, P. F.; Riise, H. N.; Vines, L.

2016-05-14

The effect of millisecond flash lamp annealing (FLA) on aluminum doped ZnO (AZO) films and their interface with Si have been studied. The AZO films were deposited by magnetron sputtering on Si (100) substrates. The electrical and structural properties of the film and AZO/Si structures were characterized by current–voltage, capacitance–voltage, and deep level transient spectroscopy measurements, X-ray diffraction, and secondary ion mass spectrometry. The resistivity of the AZO film is reduced to a close to state-of-the-art value of 2 × 10{sup −4} Ω cm after FLA for 3 ms with an average energy density of 29 J/cm{sup 2}. In addition, most of the interfacial defects energymore » levels are simultaneously annealed out, except for one persisting shallow level, tentatively assigned to the vacancy-oxygen complex in Si, which was not affected by FLA. Subsequent to the FLA, the samples were treated in N{sub 2} or forming gas (FG) (N{sub 2}/H{sub 2}, 90/10%{sub mole}) ambient at 200–500 °C. The latter samples maintained the low resistivity achieved after the FLA, but not the former ones. The interfacial defect level persisting after the FLA is removed by the FG treatment, concurrently as another level emerges at ∼0.18 eV below the conduction band. The electrical data of the AZO films are discussed in term of point defects controlling the resistivity, and it is argued that the FLA promotes formation of electrically neutral clusters of Zink vacancies (V{sub Zn}'s) rather than passivating/compensating complexes between the Al donors and V{sub Zn}'s.« less

Optical clearing of skin using flash lamp-induced enhancement of epidermal permeability.

PubMed

Tuchin, V V; Altshuler, G B; Gavrilova, A A; Pravdin, A B; Tabatadze, D; Childs, J; Yaroslavsky, I V

2006-10-01

Strong light scattering in skin prevents precise targeting of optical energy in therapeutic and diagnostic applications. Optical immersion based on matching refractive index of scattering centers with that of surrounding matter through introduction of an exogenous index-matching agent can alleviate the problem. However, slow diffusion of the index-matching agent through skin barrier makes practical implementation of this approach difficult. We propose a method of accelerating penetration of the index-matching compounds by enhancing skin permeability through creating a lattice of micro-zones (islets) of limited thermal damage in the stratum corneum (SC). A flash lamp (intense pulsed light) system and an island mask with a pattern of absorbing centers (center size approximately 75-120 microm, lattice pitch approximately 450-500 microm) were used to create the lattice of islets of damage (LID). Index-matching agents, such as glucose solution, propylene glycol solution, and glycerol solution, were applied. Experimental results of optical clearing ex vivo rat and pig skin, and ex vivo and in vivo human skin are presented. Optical transmission spectra of the skin samples with LID were measured during some 2 hours after application of index-matching chemical agents. In order to assess and compare the clearing rate under different treatment and clearing agents we calculated the quantity that we call "relative transmittance": T(rel) = I(t)(lambda)/I(0)(lambda), were I(t)(lambda) is the intensity measured at elapsed time t. The dynamics of relative transmittance of skin samples at 470 and 650 nm shows that the implementation of limited thermal damage technique leads to a 3-10-fold increase of optical clearing (rise of transmittance) rate compared to the results obtained when the samples were treated with high-intensity light pulses but without the use of island damage mask (IDM). It was observed from the plotted spectra of relative transmittance that the maximum increase of

XeNA: an automated 'open-source' (129)Xe hyperpolarizer for clinical use.

PubMed

Nikolaou, Panayiotis; Coffey, Aaron M; Walkup, Laura L; Gust, Brogan M; Whiting, Nicholas; Newton, Hayley; Muradyan, Iga; Dabaghyan, Mikayel; Ranta, Kaili; Moroz, Gregory D; Rosen, Matthew S; Patz, Samuel; Barlow, Michael J; Chekmenev, Eduard Y; Goodson, Boyd M

2014-06-01

Here we provide a full report on the construction, components, and capabilities of our consortium's "open-source" large-scale (~1L/h) (129)Xe hyperpolarizer for clinical, pre-clinical, and materials NMR/MRI (Nikolaou et al., Proc. Natl. Acad. Sci. USA, 110, 14150 (2013)). The 'hyperpolarizer' is automated and built mostly of off-the-shelf components; moreover, it is designed to be cost-effective and installed in both research laboratories and clinical settings with materials costing less than $125,000. The device runs in the xenon-rich regime (up to 1800Torr Xe in 0.5L) in either stopped-flow or single-batch mode-making cryo-collection of the hyperpolarized gas unnecessary for many applications. In-cell (129)Xe nuclear spin polarization values of ~30%-90% have been measured for Xe loadings of ~300-1600Torr. Typical (129)Xe polarization build-up and T1 relaxation time constants were ~8.5min and ~1.9h respectively under our spin-exchange optical pumping conditions; such ratios, combined with near-unity Rb electron spin polarizations enabled by the high resonant laser power (up to ~200W), permit such high PXe values to be achieved despite the high in-cell Xe densities. Importantly, most of the polarization is maintained during efficient HP gas transfer to other containers, and ultra-long (129)Xe relaxation times (up to nearly 6h) were observed in Tedlar bags following transport to a clinical 3T scanner for MR spectroscopy and imaging as a prelude to in vivo experiments. The device has received FDA IND approval for a clinical study of chronic obstructive pulmonary disease subjects. The primary focus of this paper is on the technical/engineering development of the polarizer, with the explicit goals of facilitating the adaptation of design features and operative modes into other laboratories, and of spurring the further advancement of HP-gas MR applications in biomedicine. Copyright © 2014 Elsevier Inc. All rights reserved.

Ignition of Liquid Fuel Spray and Simulated Solid Rocket Fuel by Photoignition of Carbon Nanotube Utilizing a Camera Flash

DTIC Science & Technology

2011-12-01

10,11 There has been a recent report on the photoignition of graphene oxide for fuel ignition applications.12 In this report, we will describe the...slide Aluminum foil Glass petri dish Xe flash Camera Sample Black spray paint Figure 2- Schematic and photographs of the experimental setup...Gilje, Sergey Dubin, Alireza Badakhshan, Jabari Farrar, Stephen. A. Danczyk, Richard B. Kaner, “Photothermal Deoxygenation of Graphene Oxide for

Evaluation of the RT-LAMP and LAMP methods for detection of Mycobacterium tuberculosis.

PubMed

Wu, Dandan; Kang, Jiwen; Li, Baosheng; Sun, Dianxing

2018-05-01

The current methods for detecting Mycobacterium tuberculosis (Mtb) are not clinically optimal. Standard culture methods (SCMs) are slow, costly, or unreliable, and loop-mediated isothermal amplification (LAMP) cannot differentiate live Mtb. This study compared reverse transcription (RT)-LAMP, LAMP, and an SCM for detecting Mtb. A first experiment tested the sensitivity and specificity of primers for 9 species of Mycobacterium (H37Rv, M. intracellulare, M. marinum, M. kansasii, M. avium, M. flavescens, M. smegmatis, M. fortuitum, and M. chelonae); and 3 non-Mycobacterium species (Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae). A second experiment tested sputum specimens for the presence of Mtb, from 100 patients with tuberculosis (clinical) and 22 from patients without tuberculosis (control), using Roche solid culture (SCM), LAMP, and RT-LAMP. In the clinical samples. The rates of positivity for Mtb of the SCM, LAMP, and RT-LAMP methods were 88%, 92%, and 100%, respectively. The difference in detection rate was significant between RT-LAMP and SCM, but RT-LAMP and LAMP were comparable. In the control group, the detection rates were nil for all three methods. The specificities of the methods were similar. The sensitivity of RT-LAMP was ~10-fold higher than that of LAMP for detecting Mtb. Unlike LAMP, RT-LAMP could identify viable bacteria, and was able to detect a single copy of Mtb. Among SCM, LAMP, and RT-LAMP, the latter is the most suitable for wide use in the lower-level hospitals and clinics of China for detecting Mtb in sputum samples. © 2017 Wiley Periodicals, Inc.

Hyperpolarized 131Xe NMR spectroscopy

PubMed Central

Stupic, Karl F.; Cleveland, Zackary I.; Pavlovskaya, Galina E.; Meersmann, Thomas

2011-01-01

Hyperpolarized (hp) 131Xe with up to 2.2% spin polarization (i.e., 5000-fold signal enhancement at 9.4 T) was obtained after separation from the rubidium vapor of the spin-exchange optical pumping (SEOP) process. The SEOP was applied for several minutes in a stopped-flow mode, and the fast, quadrupolar-driven T1 relaxation of this spin I = 3/2 noble gas isotope required a rapid subsequent rubidium removal and swift transfer into the high magnetic field region for NMR detection. Because of the xenon density dependent 131Xe quadrupolar relaxation in the gas phase, the SEOP polarization build-up exhibits an even more pronounced dependence on xenon partial pressure than that observed in 129Xe SEOP. 131Xe is the only stable noble gas isotope with a positive gyromagnetic ratio and shows therefore a different relative phase between hp signal and thermal signal compared to all other noble gases. The gas phase 131Xe NMR spectrum displays a surface and magnetic field dependent quadrupolar splitting that was found to have additional gas pressure and gas composition dependence. The splitting was reduced by the presence of water vapor that presumably influences xenon-surface interactions. The hp 131Xe spectrum shows differential line broadening, suggesting the presence of strong adsorption sites. Beyond hp 131Xe NMR spectroscopy studies, a general equation for the high temperature, thermal spin polarization, P, for spin I⩾1/2 nuclei is presented. PMID:21051249

Chemi-luminescence measurements of hyperthermal Xe{sup +}/Xe{sup 2+}+ NH{sub 3} reactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prince, Benjamin D.; Steiner, Colby P.; Chiu, Yu-Hui

2012-04-14

Luminescence spectra are recorded for the reactions of Xe{sup +}+ NH{sub 3} and Xe{sup 2+}+ NH{sub 3} at energies ranging from 11.5 to 206 eV in the center-of-mass (E{sub cm}) frame. Intense features of the luminescence spectra are attributed to the NH (A {sup 3}{Pi}{sub i}-X {sup 3}{Sigma}{sup -}), hydrogen Balmer series, and Xe I emission observable for both primary ions. Evidence for charge transfer products is only found through Xe I emission for both primary ions and NH{sup +} emission for Xe{sup 2+} primary ions. For both primary ions, the absolute NH (A-X) cross section increases with collision energymore » before leveling off at a constant value, approximately 9 x 10{sup -18} cm{sup 2}, at about 50 eV while H-{alpha} emission increases linearly with collision energy. The nascent NH (A) populations derived from the spectral analysis are found to be independent of collision energy and have a constant rotational temperature of 4200 K.« less

Metal-organic frameworks for Xe/Kr separation

DOEpatents

Ryan, Patrick J.; Farha, Omar K.; Broadbelt, Linda J.; Snurr, Randall Q.; Bae, Youn-Sang

2014-07-22

Metal-organic framework (MOF) materials are provided and are selectively adsorbent to xenon (Xe) over another noble gas such as krypton (Kr) and/or argon (Ar) as a result of having framework voids (pores) sized to this end. MOF materials having pores that are capable of accommodating a Xe atom but have a small enough pore size to receive no more than one Xe atom are desired to preferentially adsorb Xe over Kr in a multi-component (Xe--Kr mixture) adsorption method. The MOF material has 20% or more, preferably 40% or more, of the total pore volume in a pore size range of 0.45-0.75 nm which can selectively adsorb Xe over Kr in a multi-component Xe--Kr mixture over a pressure range of 0.01 to 1.0 MPa.

Metal-organic frameworks for Xe/Kr separation

DOEpatents

Ryan, Patrick J.; Farha, Omar K.; Broadbelt, Linda J.; Snurr, Randall Q.; Bae, Youn-Sang

2013-08-27

Metal-organic framework (MOF) materials are provided and are selectively adsorbent to xenon (Xe) over another noble gas such as krypton (Kr) and/or argon (Ar) as a result of having framework voids (pores) sized to this end. MOF materials having pores that are capable of accommodating a Xe atom but have a small enough pore size to receive no more than one Xe atom are desired to preferentially adsorb Xe over Kr in a multi-component (Xe--Kr mixture) adsorption method. The MOF material has 20% or more, preferably 40% or more, of the total pore volume in a pore size range of 0.45-0.75 nm which can selectively adsorb Xe over Kr in a multi-component Xe--Kr mixture over a pressure range of 0.01 to 1.0 MPa.

A versatile approach to organic photovoltaics evaluation using white light pulse and microwave conductivity.

PubMed

Saeki, Akinori; Yoshikawa, Saya; Tsuji, Masashi; Koizumi, Yoshiko; Ide, Marina; Vijayakumar, Chakkooth; Seki, Shu

2012-11-21

State-of-the-art low band gap conjugated polymers have been investigated for application in organic photovoltaic cells (OPVs) to achieve efficient conversion of the wide spectrum of sunlight into electricity. A remarkable improvement in power conversion efficiency (PCE) has been achieved through the use of innovative materials and device structures. However, a reliable technique for the rapid screening of the materials and processes is a prerequisite toward faster development in this area. Here we report the realization of such a versatile evaluation technique for bulk heterojunction OPVs by the combination of time-resolved microwave conductivity (TRMC) and submicrosecond white light pulse from a Xe-flash lamp. Xe-flash TRMC allows examination of the OPV active layer without requiring fabrication of the actual device. The transient photoconductivity maxima, involving information on generation efficiency, mobility, and lifetime of charge carriers in four well-known low band gap polymers blended with phenyl-C(61)-butyric acid methyl ester (PCBM), were confirmed to universally correlate with the PCE divided by the open circuit voltage (PCE/V(oc)), offering a facile way to predict photovoltaic performance without device fabrication.

Antenna induced hot restrike of a ceramic metal halide lamp recorded by high-speed photography

NASA Astrophysics Data System (ADS)

Hermanns, P.; Hoebing, T.; Bergner, A.; Ruhrmann, C.; Awakowicz, P.; Mentel, J.

2016-03-01

inner tube wall. The high-speed photos show that the ignition process is very similar in lamps with Hg or Xe as buffer gas.

Xenon in the Protoplanetary Disk (PPD-Xe)

NASA Astrophysics Data System (ADS)

Marti, K.; Mathew, K. J.

2015-06-01

Relationships among solar system Xe components as observed in the solar wind, in planetary atmospheres, and in meteorites are investigated using isotopic correlations. The term PPD-Xe is used for components inferred to have been present in the molecular cloud material that formed the protoplanetary disk (PPD). The evidence of the lack of simple relationships between terrestrial atmospheric Xe and solar or meteoritic components is confirmed. Xe isotopic correlations indicate a heterogeneous PPD composition with variable mixing ratios of the nucleosynthetic component Xe-HL. Solar Xe represents a bulk PPD component, and the isotopic abundances did not change from the time of incorporation into the interior of Mars through times of regolith implantations to the present.

XeNA: An automated ‘open-source’ 129Xe hyperpolarizer for clinical use

PubMed Central

Nikolaou, Panayiotis; Coffey, Aaron M.; Walkup, Laura L.; Gust, Brogan M.; Whiting, Nicholas; Newton, Hayley; Muradyan, Iga; Dabaghyan, Mikayel; Ranta, Kaili; Moroz, Gregory D.; Rosen, Matthew S.; Patz, Samuel; Barlow, Michael J.; Chekmenev, Eduard Y.; Goodson, Boyd M.

2014-01-01

Here we provide a full report on the construction, components, and capabilities of our consortium’s “open-source” large-scale (~1 L/hr) 129Xe hyperpolarizer for clinical, pre-clinical, and materials NMR/MRI (Nikolaou et al., Proc. Natl. Acad. Sci. USA, 110, 14150 (2013)). The ‘hyperpolarizer’ is automated and built mostly of off-the-shelf components; moreover, it is designed to be cost-effective and installed in both research laboratories and clinical settings with materials costing less than $125,000. The device runs in the xenon-rich regime (up to 1800 Torr Xe in 0.5 L) in either stopped-flow or single-batch mode—making cryo-collection of the hyperpolarized gas unnecessary for many applications. In-cell 129Xe nuclear spin polarization values of ~30-90% have been measured for Xe loadings of ~300-1600 Torr. Typical 129Xe polarization build-up and T1 relaxation time constants were ~8.5 min and ~1.9 hr respectively under our SEOP conditions; such ratios, combined with near-unity Rb electron spin polarizations enabled by the high resonant laser power (up to ~200 W), permits such high PXe values to be achieved despite the high in-cell Xe densities. Importantly, most of the polarization is maintained during efficient HP gas transfer to other containers, and ultra-long 129Xe relaxation times (up to nearly 6 hr) were observed in Tedlar bags following transport to a clinical 3 T scanner for MR spectroscopy and imaging as a prelude to in vivo experiments. The device has received FDA IND approval for a clinical study of COPD subjects. The primary focus of this paper is on the technical / engineering development of the polarizer, with the explicit goals of facilitating the adaptation of design features and operative modes into other laboratories, and of spurring the further advancement of HP-gas MR applications in biomedicine. PMID:24631715

High-spin structures in 132Xe and 133Xe and evidence for isomers along the N =79 isotones

NASA Astrophysics Data System (ADS)

Vogt, A.; Siciliano, M.; Birkenbach, B.; Reiter, P.; Hadyńska-Klek, K.; Wheldon, C.; Valiente-Dobón, J. J.; Teruya, E.; Yoshinaga, N.; Arnswald, K.; Bazzacco, D.; Blazhev, A.; Bracco, A.; Bruyneel, B.; Chakrawarthy, R. S.; Chapman, R.; Cline, D.; Corradi, L.; Crespi, F. C. L.; Cromaz, M.; de Angelis, G.; Eberth, J.; Fallon, P.; Farnea, E.; Fioretto, E.; Fransen, C.; Freeman, S. J.; Fu, B.; Gadea, A.; Gelletly, W.; Giaz, A.; Görgen, A.; Gottardo, A.; Hayes, A. B.; Hess, H.; Hetzenegger, R.; Hirsch, R.; Hua, H.; John, P. R.; Jolie, J.; Jungclaus, A.; Karayonchev, V.; Kaya, L.; Korten, W.; Lee, I. Y.; Leoni, S.; Liang, X.; Lunardi, S.; Macchiavelli, A. O.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Müller-Gatermann, C.; Napoli, D.; Pearson, C. J.; Podolyák, Zs.; Pollarolo, G.; Pullia, A.; Queiser, M.; Recchia, F.; Regan, P. H.; Régis, J.-M.; Saed-Samii, N.; Şahin, E.; Scarlassara, F.; Seidlitz, M.; Siebeck, B.; Sletten, G.; Smith, J. F.; Söderström, P.-A.; Stefanini, A. M.; Stezowski, O.; Szilner, S.; Szpak, B.; Teng, R.; Ur, C.; Warner, D. D.; Wolf, K.; Wu, C. Y.; Zell, K. O.

2017-08-01

The transitional nuclei 132Xe and 133Xe are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in 136Xe+208Pb MNT reactions employing the high-resolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (ii) in the 136Xe+198Pt MNT reaction employing the GAMMASPHERE spectrometer in combination with the gas-detector array CHICO, and (iii) as an evaporation residue after a 130Te(α ,x n )134 -x nXe fusion-evaporation reaction employing the HORUS γ -ray array at the University of Cologne. The high-spin level schemes are considerably extended above the Jπ=(7-) and (10+) isomers in 132Xe and above the 11 /2- isomer in 133Xe. The results are compared to the high-spin systematics of the Z =54 as well as the N =78 and N =79 chains. Furthermore, evidence is found for a long-lived (T1 /2≫1 μ s ) isomer in 133Xe which closes a gap along the N =79 isotones. Shell-model calculations employing the SN100PN and PQM130 effective interactions reproduce the experimental findings and provide guidance to the interpretation of the observed high-spin features.

High-spin structures in Xe 132 and Xe 133 and evidence for isomers along the N = 79 isotones

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vogt, A.; Siciliano, M.; Birkenbach, B.

In this study, the transitional nuclei 132Xe and 133Xe are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in 136Xe + 208Pb MNT reactions employing the high-resolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (ii) in the 136Xe + 198Pt MNT reaction employing the GAMMASPHERE spectrometer in combination with the gas-detector array CHICO, and (iii) as an evaporation residue after a 130Te (α,xn) 134-xnXe fusion-evaporation reaction employing the HORUS γ -ray array at the University of Cologne. The high-spin level schemes are considerably extended above the J π = (7 -) andmore » (10 +) isomers in 132Xe and above the 11/2 - isomer in 133Xe. The results are compared to the high-spin systematics of the Z = 54 as well as the N = 78 and N = 79 chains. Furthermore, evidence is found for a long-lived (T 1/2 » 1 μs) isomer in 133Xe which closes a gap along the N = 79 isotones. Finally, shell-model calculations employing the SN100PN and PQM130 effective interactions reproduce the experimental findings and provide guidance to the interpretation of the observed high-spin features.« less

High-spin structures in Xe 132 and Xe 133 and evidence for isomers along the N = 79 isotones

DOE PAGES

Vogt, A.; Siciliano, M.; Birkenbach, B.; ...

2017-08-24

In this study, the transitional nuclei 132Xe and 133Xe are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in 136Xe + 208Pb MNT reactions employing the high-resolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (ii) in the 136Xe + 198Pt MNT reaction employing the GAMMASPHERE spectrometer in combination with the gas-detector array CHICO, and (iii) as an evaporation residue after a 130Te (α,xn) 134-xnXe fusion-evaporation reaction employing the HORUS γ -ray array at the University of Cologne. The high-spin level schemes are considerably extended above the J π = (7 -) andmore » (10 +) isomers in 132Xe and above the 11/2 - isomer in 133Xe. The results are compared to the high-spin systematics of the Z = 54 as well as the N = 78 and N = 79 chains. Furthermore, evidence is found for a long-lived (T 1/2 » 1 μs) isomer in 133Xe which closes a gap along the N = 79 isotones. Finally, shell-model calculations employing the SN100PN and PQM130 effective interactions reproduce the experimental findings and provide guidance to the interpretation of the observed high-spin features.« less

High energy XeBr electric discharge laser

DOEpatents

Sze, Robert C.; Scott, Peter B.

1981-01-01

A high energy XeBr laser for producing coherent radiation at 282 nm. The XeBr laser utilizes an electric discharge as the excitation source to minimize formation of molecular ions thereby minimizing absorption of laser radiation by the active medium. Additionally, HBr is used as the halogen donor which undergoes harpooning reactions with Xe.sub.M * to form XeBr*.

High energy XeBr electric discharge laser

DOEpatents

Sze, R.C.; Scott, P.B.

A high energy XeBr laser for producing coherent radiation at 282 nm is disclosed. The XeBr laser utilizes an electric discharge as the excitation source to minimize formation of molecular ions thereby minimizing absorption of laser radiation by the active medium. Additionally, HBr, is used as the halogen donor which undergoes harpooning reactions with Xe/sub M/ to form XeBr.

Xenon in the protoplanetary disk (PPD-XE)

DOE PAGES

Marti, K.; Mathew, K. J.

2015-06-18

Relationships among solar system Xe components as observed in the solar wind (SW), in planetary atmospheres and in meteorites are investigated using isotopic correlations. The term PPD-Xe is used for components inferred to have been present in the molecular cloud material that formed the protoplanetary disk (PPD). The evidence of the lack of simple relationships between terrestrial atmospheric Xe and solar or meteoritic components is confirmed. Xe isotopic correlations indicate a heterogeneous PPD composition with variable mixing ratios of the nucleosynthetic component Xe-HL. Solar Xe represents a bulk PPD component, and the isotopic abundances did not change from the timemore » of incorporation into the interior of Mars, through times of regolith implantations to the present.« less

Lysosome-associated membrane proteins-1 and -2 (LAMP-1 and LAMP-2) assemble via distinct modes.

PubMed

Terasawa, Kazue; Tomabechi, Yuri; Ikeda, Mariko; Ehara, Haruhiko; Kukimoto-Niino, Mutsuko; Wakiyama, Motoaki; Podyma-Inoue, Katarzyna A; Rajapakshe, Anupama R; Watabe, Tetsuro; Shirouzu, Mikako; Hara-Yokoyama, Miki

2016-10-21

Lysosome-associated membrane proteins 1 and 2 (LAMP-1 and LAMP-2) have a large, heavily glycosylated luminal domain composed of two subdomains, and are the most abundant protein components in lysosome membranes. LAMP-1 and LAMP-2 have distinct functions, and the presence of both proteins together is required for the essential regulation of autophagy to avoid embryonic lethality. However, the structural aspects of LAMP-1 and LAMP-2 have not been elucidated. In the present study, we demonstrated that the subdomains of LAMP-1 and LAMP-2 adopt the unique β-prism fold, similar to the domain structure of the dendritic cell-specific-LAMP (DC-LAMP, LAMP-3), confirming the conserved aspect of this family of lysosome-associated membrane proteins. Furthermore, we evaluated the effects of the N-domain truncation of LAMP-1 or LAMP-2 on the assembly of LAMPs, based on immunoprecipitation experiments. We found that the N-domain of LAMP-1 is necessary, whereas that of LAMP-2 is repressive, for the organization of a multimeric assembly of LAMPs. Accordingly, the present study suggests for the first time that the assembly modes of LAMP-1 and LAMP-2 are different, which may underlie their distinct functions. Copyright © 2016 Elsevier Inc. All rights reserved.

Flash-induced nanowelding of silver nanowire networks for transparent stretchable electrochromic devices.

PubMed

Lee, Chihak; Oh, Youngsu; Yoon, In Seon; Kim, Sun Hong; Ju, Byeong-Kwon; Hong, Jae-Min

2018-02-09

Electrochromic devices (ECDs) are emerging as a novel technology for various applications like commercialized smart window glasses, and auto-dimming rear-view mirrors. Recently, the development of low-power, lightweight, flexible, and stretchable devices has been accelerated to meet the growing demand in the new wearable devices market. Silver nanowires (AgNWs) can become new primary transparent conducting electrode (TCE) materials to replace indium tin oxide (ITO) for ECDs. However, issues such as substrate adhesion, delamination, and higher resistance still exist with AgNWs. Herein, we report a high-performance stretchable flash-induced AgNW-network-based TCE on surface-treated polydimethylsiloxane (PDMS) substrates. A Xe flash light method was used to create nanowelded networks of AgNWs. Surface silane treatments increased the adhesion and durability of the films as well. Finally, ECDs were fabricated under the optimal conditions and examined under strained conditions to demonstrate the resistance and mechanical behaviours of the devices. Results showed a flexible and durable film maintaining a high level of conductivity and reversible resistance behaviour, beyond those currently achievable with standard ITO/PET flexible TCEs.

Fast repetition rate (FRR) flasher

DOEpatents

Kolber, Z.; Falkowski, P.

1997-02-11

A fast repetition rate (FRR) flasher is described suitable for high flash photolysis including kinetic chemical and biological analysis. The flasher includes a power supply, a discharge capacitor operably connected to be charged by the power supply, and a flash lamp for producing a series of flashes in response to discharge of the discharge capacitor. A triggering circuit operably connected to the flash lamp initially ionizes the flash lamp. A current switch is operably connected between the flash lamp and the discharge capacitor. The current switch has at least one insulated gate bipolar transistor for switching current that is operable to initiate a controllable discharge of the discharge capacitor through the flash lamp. Control means connected to the current switch for controlling the rate of discharge of the discharge capacitor thereby to effectively keep the flash lamp in an ionized state between successive discharges of the discharge capacitor. Advantageously, the control means is operable to discharge the discharge capacitor at a rate greater than 10,000 Hz and even up to a rate greater than about 250,000 Hz. 14 figs.

Fast repetition rate (FRR) flasher

DOEpatents

Kolber, Zbigniew; Falkowski, Paul

1997-02-11

A fast repetition rate (FRR) flasher suitable for high flash photolysis including kinetic chemical and biological analysis. The flasher includes a power supply, a discharge capacitor operably connected to be charged by the power supply, and a flash lamp for producing a series of flashes in response to discharge of the discharge capacitor. A triggering circuit operably connected to the flash lamp initially ionizes the flash lamp. A current switch is operably connected between the flash lamp and the discharge capacitor. The current switch has at least one insulated gate bipolar transistor for switching current that is operable to initiate a controllable discharge of the discharge capacitor through the flash lamp. Control means connected to the current switch for controlling the rate of discharge of the discharge capacitor thereby to effectively keep the flash lamp in an ionized state between Successive discharges of the discharge capacitor. Advantageously, the control means is operable to discharge the discharge capacitor at a rate greater than 10,000 Hz and even up to a rate greater than about 250,000 Hz.

10 CFR 429.40 - Candelabra base incandescent lamps and intermediate base incandescent lamps.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 3 2014-01-01 2014-01-01 false Candelabra base incandescent lamps and intermediate base incandescent lamps. 429.40 Section 429.40 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION....40 Candelabra base incandescent lamps and intermediate base incandescent lamps. (a) Sampling plan for...

129 Xe chemical shift in human blood and pulmonary blood oxygenation measurement in humans using hyperpolarized 129 Xe NMR.

PubMed

Norquay, Graham; Leung, General; Stewart, Neil J; Wolber, Jan; Wild, Jim M

2017-04-01

To evaluate the dependency of the 129 Xe-red blood cell (RBC) chemical shift on blood oxygenation, and to use this relation for noninvasive measurement of pulmonary blood oxygenation in vivo with hyperpolarized 129 Xe NMR. Hyperpolarized 129 Xe was equilibrated with blood samples of varying oxygenation in vitro, and NMR was performed at 1.5 T and 3 T. Dynamic in vivo NMR during breath hold apnea was performed at 3 T on two healthy volunteers following inhalation of hyperpolarized 129 Xe. The 129 Xe chemical shift in RBCs was found to increase nonlinearly with blood oxygenation at 1.5 T and 3 T. During breath hold apnea, the 129 Xe chemical shift in RBCs exhibited a periodic time modulation and showed a net decrease in chemical shift of ∼1 ppm over a 35 s breath hold, corresponding to a decrease of 7-10 % in RBC oxygenation. The 129 Xe-RBC signal amplitude showed a modulation with the same frequency as the 129 Xe-RBC chemical shift. The feasibility of using the 129 Xe-RBC chemical shift to measure pulmonary blood oxygenation in vivo has been demonstrated. Correlation between 129 Xe-RBC signal and 129 Xe-RBC chemical shift modulations in the lung warrants further investigation, with the aim to better quantify temporal blood oxygenation changes in the cardiopulmonary vascular circuit. Magn Reson Med 77:1399-1408, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.

High-spin structure of 134Xe

NASA Astrophysics Data System (ADS)

Vogt, A.; Birkenbach, B.; Reiter, P.; Blazhev, A.; Siciliano, M.; Valiente-Dobón, J. J.; Wheldon, C.; Bazzacco, D.; Bowry, M.; Bracco, A.; Bruyneel, B.; Chakrawarthy, R. S.; Chapman, R.; Cline, D.; Corradi, L.; Crespi, F. C. L.; Cromaz, M.; de Angelis, G.; Eberth, J.; Fallon, P.; Farnea, E.; Fioretto, E.; Freeman, S. J.; Gadea, A.; Geibel, K.; Gelletly, W.; Gengelbach, A.; Giaz, A.; Görgen, A.; Gottardo, A.; Hayes, A. B.; Hess, H.; Hua, H.; John, P. R.; Jolie, J.; Jungclaus, A.; Korten, W.; Lee, I. Y.; Leoni, S.; Liang, X.; Lunardi, S.; Macchiavelli, A. O.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Napoli, D.; Pearson, C. J.; Pellegri, L.; Podolyák, Zs.; Pollarolo, G.; Pullia, A.; Radeck, F.; Recchia, F.; Regan, P. H.; Şahin, E.; Scarlassara, F.; Sletten, G.; Smith, J. F.; Söderström, P.-A.; Stefanini, A. M.; Steinbach, T.; Stezowski, O.; Szilner, S.; Szpak, B.; Teng, R.; Ur, C.; Vandone, V.; Ward, D.; Warner, D. D.; Wiens, A.; Wu, C. Y.

2016-05-01

Detailed spectroscopic information on the N ˜82 nuclei is necessary to benchmark shell-model calculations in the region. The nuclear structure above long-lived isomers in 134Xe is investigated after multinucleon transfer (MNT) and actinide fission. Xenon-134 was populated as (i) a transfer product in 238U+ 136Xe and 208Pb+ 136Xe MNT reactions and (ii) as a fission product in the 238U+ 136Xe reaction employing the high-resolution Advanced Gamma Tracking Array (AGATA). Trajectory reconstruction has been applied for the complete identification of beamlike transfer products with the magnetic spectrometer PRISMA. The 198Pt 136Xe MNT reaction was studied with the γ -ray spectrometer GAMMASPHERE in combination with the gas detector array Compact Heavy Ion Counter (CHICO). Several high-spin states in 134Xe on top of the two long-lived isomers are discovered based on γ γ -coincidence relationships and information on the γ -ray angular distributions as well as excitation energies from the total kinetic energy loss and fission fragments. The revised level scheme of 134Xe is extended up to an excitation energy of 5.832 MeV with tentative spin-parity assignments up to 16+. Previous assignments of states above the 7- isomer are revised. Latest shell-model calculations employing two different effective interactions reproduce the experimental findings and support the new spin and parity assignments.

Biological Studies with Laser-Polarized ^129Xe

NASA Astrophysics Data System (ADS)

Tseng, C. H.; Oteiza, E. R.; Wong, G. A.; Walsworth, R. L.; Albert, M. S.; Nascimben, L.; Peled, S.; Sakai, K.; Jolesz, F. A.

1996-05-01

We have studied several biological systems using laser-polarized ^129Xe. In certain tissues magnetic resonance imaging (MRI) using inhaled laser-polarized noble gases may provide images superior to those from conventional proton MRI. High resolution laser-polarized ^3He images of air spaces in the human lung were recently obtained by the Princeton/Duke group. However, ^3He is not very soluble in tissue. Therefore, we are using laser polarized ^129Xe (tissue-soluble), with the long term goal of biomedical functional imaging. We have investigated multi-echo and multi-excitation magnetic resonance detection schemes to exploit the highly non-thermal ^129Xe magnetization produced by the laser polarization technique. We have inhalated live rats with laser-polarized ^129Xe gas and measured three distinct ^129Xe tissue resonances that last 20 to 40 sec. As a demonstration, we obtained a laser polarized ^129Xe image of the human oral cavity. Currently we are measuring the polarization lifetime of ^129Xe dissolved in human blood, the biological transporting medium. These studies and other recent developments will be reported.

Emission characteristics of Xe-RbBr plasma

NASA Astrophysics Data System (ADS)

Heneral, A. A.; Avtaeva, S. V.

2017-12-01

The luminescence spectra of the longitudinal pulsed-periodic discharge in Xe-RbBr gas-vapour mixtures at low pressures are experimentally studied. Conditions for obtaining strong UV radiation of XeBr* exiplex molecules in the spectral range of 200-425 nm are found. The greatest output of the XeBr* UV radiation is provided at temperature of the gas-discharge tube walls of ~1000 K. The maximum UV emission power of the whole plasma volume is 4.8 W. Formation of XeBr* exciplex molecules in the pulsed-periodic discharge in Xe-RbBr gas-vapour mixtures at low pressures is discussed.

Driving lamps by induction

NASA Technical Reports Server (NTRS)

Laue, H. H.; Clough, L. G. (Inventor)

1973-01-01

An electrodeless lamp circuit with a coil surrounding a krypton lamp is driven by an RF input source. A coil surrounding a mercury lamp is tapped across the connection of the input central to the krypton-lamp coil. Each coil is connected in parallel with separate capacitors which form resonant circuits at the input frequency.

The 129Xe nuclear shielding surfaces for Xe interacting with linear molecules CO2, N2, and CO

NASA Astrophysics Data System (ADS)

de Dios, Angel C.; Jameson, Cynthia J.

1997-09-01

We have calculated the intermolecular nuclear magnetic shielding surfaces for 129Xe in the systems Xe-CO2, Xe-N2, and Xe-CO using a gauge-invariant ab initio method at the coupled Hartree-Fock level with gauge-including atomic orbitals (GIAO). Implementation of a large basis set (240 basis functions) on the Xe gives very small counterpoise corrections which indicates that the basis set superposition errors in the calculated shielding values are negligible. These are the first intermolecular shielding surfaces for Xe-molecule systems. The surfaces are highly anisotropic and can be described adequately by a sum of inverse even powers of the distance with explicit angle dependence in the coefficients expressed by Legendre polynomials P2n(cos θ), n=0-3, for Xe-CO2 and Xe-N2. The Xe-CO shielding surface is well described by a similar functional form, except that Pn(cos θ), n=0-4 were used. When averaged over the anisotropic potential function these shielding surfaces provide the second virial coefficient of the nuclear magnetic resonance (NMR) chemical shift observed in gas mixtures. The energies from the self-consistent field (SCF) calculations were used to construct potential surfaces, using a damped dispersion form. These potential functions are compared with existing potentials in their predictions of the second virial coefficients of NMR shielding, the pressure virial coefficients, the density coefficient of the mean-square torque from infrared absorption, and the rotational constants and other average properties of the van der Waals complexes. Average properties of the van der Waals complexes were obtained by quantum diffusion Monte Carlo solutions of the vibrational motion using the various potentials and compared with experiment.

Pseudopotential SCF-MO studies of hypervalent compounds. II. XeF+5 and XeF6

NASA Astrophysics Data System (ADS)

Rothman, Michael J.; Bartell, Lawrence S.; Ewig, Carl S.; Van Wazer, John R.

1980-07-01

New evidence bearing upon the anomalous properties of xenon hexafluoride has been obtained via the ab initio molecular orbital approach applied successfully to the di- and tetrafluorides in paper I. Structures of both XeF+5 and XeF6 are governed by a stereochemically active lone pair. In the case of the square-pyramidal cation the Fax-Xe-Feq angle calculated for the bare ion is within 2° of the value observed in the crystalline complex. For the hexafluoride, however, the calculated deformation from Oh symmetry is appreciably greater than that deduced from electron diffraction intensities. Nevertheless, the results of calculations are in sufficient conformity with the Bartell-Gavin, Pitzer-Bernstein interpretation and at variance with the ''electronic-isomers'' interpretation to leave little doubt about the answer. With increasing fluorination in the XeFn series the HOMO-LUMO energy difference decreases and the second-order Jahn-Teller effect is enhanced. Increasing fluorination (and increased positive charge on Xe) also shortens bond lengths; calculated shortenings parallel observed shortenings. The deformation of XeF6 from Oh is along t1u bend and stretch coordinates to a C3v structure with long bonds adjacent to the lone pair, as expected according to the valence-shell-electron-pair-repulsion model. Pure t2g deformations are destabilizing but anharmonic t1u-t2g coupling significantly stabilizes the deformation. Steric aspects of the structure and force field are diagnosed and found to be minor. Values for the force constants f44, f55, f¯4444, f¯444'4', and f¯445 are derived and found to be of the magnitude forecast in the Bartell-Gavin and Pitzer-Bernstein treatments except that the calculations do not reproduce the delicate balances believed to lead to almost free pseudorotation in XeF6.

Hot Flashes

MedlinePlus

... report menopausal hot flashes than do women of European descent. Hot flashes are less common in women of Japanese and Chinese descent than in white European women. Complications Nighttime hot flashes (night sweats) can ...

129Xe NMR chemical shift in Xe@C60 calculated at experimental conditions: essential role of the relativity, dynamics, and explicit solvent.

PubMed

Standara, Stanislav; Kulhánek, Petr; Marek, Radek; Straka, Michal

2013-08-15

The isotropic (129)Xe nuclear magnetic resonance (NMR) chemical shift (CS) in Xe@C60 dissolved in liquid benzene was calculated by piecewise approximation to faithfully simulate the experimental conditions and to evaluate the role of different physical factors influencing the (129)Xe NMR CS. The (129)Xe shielding constant was obtained by averaging the (129)Xe nuclear magnetic shieldings calculated for snapshots obtained from the molecular dynamics trajectory of the Xe@C60 system embedded in a periodic box of benzene molecules. Relativistic corrections were added at the Breit-Pauli perturbation theory (BPPT) level, included the solvent, and were dynamically averaged. It is demonstrated that the contribution of internal dynamics of the Xe@C60 system represents about 8% of the total nonrelativistic NMR CS, whereas the effects of dynamical solvent add another 8%. The dynamically averaged relativistic effects contribute by 9% to the total calculated (129)Xe NMR CS. The final theoretical value of 172.7 ppm corresponds well to the experimental (129)Xe CS of 179.2 ppm and lies within the estimated errors of the model. The presented computational protocol serves as a prototype for calculations of (129)Xe NMR parameters in different Xe atom guest-host systems. Copyright © 2013 Wiley Periodicals, Inc.

Molecular dynamics averaging of Xe chemical shifts in liquids.

PubMed

Jameson, Cynthia J; Sears, Devin N; Murad, Sohail

2004-11-15

The Xe nuclear magnetic resonance chemical shift differences that afford the discrimination between various biological environments are of current interest for biosensor applications and medical diagnostic purposes. In many such environments the Xe signal appears close to that in water. We calculate average Xe chemical shifts (relative to the free Xe atom) in solution in eleven liquids: water, isobutane, perfluoro-isobutane, n-butane, n-pentane, neopentane, perfluoroneopentane, n-hexane, n-octane, n-perfluorooctane, and perfluorooctyl bromide. The latter is a liquid used for intravenous Xe delivery. We calculate quantum mechanically the Xe shielding response in Xe-molecule van der Waals complexes, from which calculations we develop Xe (atomic site) interpolating functions that reproduce the ab initio Xe shielding response in the complex. By assuming additivity, these Xe-site shielding functions can be used to calculate the shielding for any configuration of such molecules around Xe. The averaging over configurations is done via molecular dynamics (MD). The simulations were carried out using a MD technique that one of us had developed previously for the simulation of Henry's constants of gases dissolved in liquids. It is based on separating a gaseous compartment in the MD system from the solvent using a semipermeable membrane that is permeable only to the gas molecules. We reproduce the experimental trends in the Xe chemical shifts in n-alkanes with increasing number of carbons and the large chemical shift difference between Xe in water and in perfluorooctyl bromide. We also reproduce the trend for a given solvent of decreasing Xe chemical shift with increasing temperature. We predict chemical shift differences between Xe in alkanes vs their perfluoro counterparts.

Hollow-Core Fiber Lamp

NASA Technical Reports Server (NTRS)

Yi, Lin (Inventor); Tjoelker, Robert L. (Inventor); Burt, Eric A. (Inventor); Huang, Shouhua (Inventor)

2016-01-01

Hollow-core capillary discharge lamps on the millimeter or sub-millimeter scale are provided. The hollow-core capillary discharge lamps achieve an increased light intensity ratio between 194 millimeters (useful) and 254 millimeters (useless) light than conventional lamps. The capillary discharge lamps may include a cone to increase light output. Hollow-core photonic crystal fiber (HCPCF) may also be used.

Syntheses, Raman spectra, and X-ray crystal structures of [XeF(5)][mu-F(OsO(3)F(2))(2)] and [M][OsO(3)F(3)] (M = XeF(5)(+), Xe(2)F(11)(+)).

PubMed

Hughes, Michael J; Mercier, Hélène P A; Schrobilgen, Gary J

2010-04-05

Stoichiometric amounts of XeF(6) and (OsO(3)F(2))(infinity) react at 25-50 degrees C to form salts of the known XeF(5)(+) and Xe(2)F(11)(+) cations, namely, [XeF(5)][mu-F(OsO(3)F(2))(2)], [XeF(5)][OsO(3)F(3)], and [Xe(2)F(11)][OsO(3)F(3)]. Although XeF(6) is oxophilic toward a number of transition metal and main-group oxides and oxide fluorides, fluoride/oxide metathesis was not observed. The series provides the first examples of noble-gas cations that are stabilized by metal oxide fluoride anions and the first example of a mu-F(OsO(3)F(2))(2)(-) salt. Both [XeF(5)][mu-F(OsO(3)F(2))(2)] and [Xe(2)F(11)][OsO(3)F(3)] are orange solids at room temperature. The [XeF(5)][OsO(3)F(3)] salt is an orange liquid at room temperature that solidifies at 5-0 degrees C. When the salts are heated at 50 degrees C under 1 atm of N(2) for more than 2 h, significant XeF(6) loss occurs. The X-ray crystal structures (-173 degrees C) show that the salts exist as discrete ion pairs and that the osmium coordination spheres in OsO(3)F(3)(-) and mu-F(OsO(3)F(2))(2)(-) are pseudo-octahedral OsO(3)F(3)-units having facial arrangements of oxygen and fluorine atoms. The mu-F(OsO(3)F(2))(2)(-) anion is comprised of two symmetry-related OsO(3)F(2)-groups that are fluorine-bridged to one another. Ion pairing results from secondary bonding interactions between the fluorine/oxygen atoms of the anions and the xenon atom of the cation, with the Xe...F/O contacts occurring opposite the axial fluorine and from beneath the equatorial XeF(4)-planes of the XeF(5)(+) and Xe(2)F(11)(+) cations so as to avoid the free valence electron lone pairs of the xenon atoms. The xenon atoms of [XeF(5)][mu-F(OsO(3)F(2))(2)] and [Xe(2)F(11)][OsO(3)F(3)] are nine-coordinate and the xenon atom of [XeF(5)][OsO(3)F(3)] is eight-coordinate. Quantum-chemical calculations at SVWN and B3LYP levels of theory were used to obtain the gas-phase geometries, vibrational frequencies, and NBO bond orders, valencies, and NPA charges of

10 CFR 429.27 - General service fluorescent lamps, general service incandescent lamps, and incandescent reflector...

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 3 2014-01-01 2014-01-01 false General service fluorescent lamps, general service incandescent lamps, and incandescent reflector lamps. 429.27 Section 429.27 Energy DEPARTMENT OF ENERGY ENERGY... EQUIPMENT Certification § 429.27 General service fluorescent lamps, general service incandescent lamps, and...

10 CFR 429.27 - General service fluorescent lamps, general service incandescent lamps, and incandescent reflector...

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 3 2012-01-01 2012-01-01 false General service fluorescent lamps, general service incandescent lamps, and incandescent reflector lamps. 429.27 Section 429.27 Energy DEPARTMENT OF ENERGY ENERGY... EQUIPMENT Certification § 429.27 General service fluorescent lamps, general service incandescent lamps, and...

10 CFR 429.27 - General service fluorescent lamps, general service incandescent lamps, and incandescent reflector...

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 3 2013-01-01 2013-01-01 false General service fluorescent lamps, general service incandescent lamps, and incandescent reflector lamps. 429.27 Section 429.27 Energy DEPARTMENT OF ENERGY ENERGY... EQUIPMENT Certification § 429.27 General service fluorescent lamps, general service incandescent lamps, and...

Toward calculations of the 129Xe chemical shift in Xe@C60 at experimental conditions: relativity, correlation, and dynamics.

PubMed

Straka, Michal; Lantto, Perttu; Vaara, Juha

2008-03-27

We calculate the 129Xe chemical shift in endohedral Xe@C60 with systematic inclusion of the contributing physical effects to model the real experimental conditions. These are relativistic effects, electron correlation, the temperature-dependent dynamics, and solvent effects. The ultimate task is to obtain the right result for the right reason and to develop a physically justified methodological model for calculations and simulations of endohedral Xe fullerenes and other confined Xe systems. We use the smaller Xe...C6H6 model to calibrate density functional theory approaches against accurate correlated wave function methods. Relativistic effects as well as the coupling of relativity and electron correlation are evaluated using the leading-order Breit-Pauli perturbation theory. The dynamic effects are treated in two ways. In the first approximation, quantum dynamics of the Xe atom in a rigid cage takes advantage of the centrosymmetric potential for Xe within the thermally accessible distance range from the center of the cage. This reduces the problem of obtaining the solution of a diatomic rovibrational problem. In the second approach, first-principles classical molecular dynamics on the density functional potential energy hypersurface is used to produce the dynamical trajectory for the whole system, including the dynamic cage. Snapshots from the trajectory are used for calculations of the dynamic contribution to the absorption 129Xe chemical shift. The calculated nonrelativistic Xe shift is found to be highly sensitive to the optimized molecular structure and to the choice of the exchange-correlation functional. Relativistic and dynamic effects are significant and represent each about 10% of the nonrelativistic static shift at the minimum structure. While the role of the Xe dynamics inside of the rigid cage is negligible, the cage dynamics turns out to be responsible for most of the dynamical correction to the 129Xe shift. Solvent effects evaluated with a polarized

Expansion and melting of Xe nanocrystals in Si

NASA Astrophysics Data System (ADS)

Faraci, Giuseppe; Pennisi, Agata R.; Zontone, Federico; Li, Boquan; Petrov, Ivan

2006-12-01

Xe agglomerates confined in a Si matrix by ion implantation were synthesized with different size depending on the implantation process and/or the thermal treatment. At low temperature Xe nanocrystals are formed, whose expansion and melting were studied in the range 15- 300K . Previous high resolution x-ray diffraction spectra were corroborated with complementary techniques such as two-dimensional imaging plate patterns and transmission electron microscopy. We detected fcc Xe nanocrystals whose properties were size dependent. The experiments showed that in annealed samples epitaxial condensation of small Xe clusters, on the cavities of the Si matrix, gave in fact expanded and oriented Xe, suggesting a possible preferential growth of Xe(311) planes oriented orthogonally to the Si[02-2] direction. On the contrary, small Xe clusters in an amorphous Si matrix have a fcc lattice contracted as a consequence of surface tension. Furthermore, a solid-to-liquid phase transition size dependent was found. Expansion of fcc Xe lattice was accurately determined as a function of the temperature. Overpressurized nanocrystals and/or binary size distributions were disproved.

Halogen lamp experiment, HALEX

NASA Technical Reports Server (NTRS)

Schmitt, G.; Stapelmann, J.

1986-01-01

The main purpose of the Halogen Lamp Experiment (HALEX) was to investigate the operation of a halogen lamp during an extended period in a microgravity environment and to prove its behavior in space. The Mirror Heating Facilities for Crystal Growth and Material Science Experiments in space relies on one or two halogen lamps as a furnace to melt the specimens. The HALEX aim is to verify: full power operation of a halogen lamp for a period of about 60 hours; achievement of about 10% of its terrestrial life span; and operation of the halogen lamp under conditions similar to furnace operation.

49 CFR 393.24 - Requirements for head lamps, auxiliary driving lamps and front fog lamps.

Code of Federal Regulations, 2011 CFR

2011-10-01

... the driver's will and be steady-burning. The headlamps shall be marked in accordance with FMVSS No... this paragraph. (b) Auxiliary driving lamps and front fog lamps. Commercial motor vehicles may be... aim of the lighting device from being disturbed while the vehicle is operating on public roads. (d...

Discharge lamp technologies

NASA Technical Reports Server (NTRS)

Dakin, James

1994-01-01

This talk is an overview of discharge lamp technology commonly employed in general lighting, with emphasis on issues pertinent to lighting for plant growth. Since the audience is primarily from the plant growth community, and this begins the light source part of the program, we will start with a brief description of the discharge lamps. Challenges of economics and of thermal management make lamp efficiency a prime concern in controlled environment agriculture, so we will emphasize science considerations relating to discharge lamp efficiency. We will then look at the spectra and ratings of some representative lighting products, and conclude with a discussion of technological advances.

Dimming of metal halide lamps

NASA Astrophysics Data System (ADS)

Schurer, Kees

1994-03-01

We ran some tests on the effect of dimming of metal halide (MH) lamps upon the stability and the spectral quality of the light output. Lamps used were a new Philips lamp HPI-T 250W, a similar Philips lamp with a few thousand burning hours and a new Osram lamp HQI-T 250W/D. The ballast was a BBC type DJ 250/2KS, the starter a BAS TORGI type MZN 250 SE and the dimmer an Elstrom Control System type ERHQ-T 250. Power was derived from a Philips stabilizer, type PE 1602. Lamp output was monitored with a PAR meter. Spectra were taken at 100% and at 50% output as measured with the PAR meter. Lamps were allowed to stabilize at any setting for 30 minutes before measurements were made. Lamp manufacturers advise against dimming for fear of poor stability and intolerable changes of the spectrum. However, none of the lamps showed a decrease in stability, no flicker or wandering of the discharge, and the changes of the spectrum were not negligible, but certainly not dramatic. Lamps of either manufacture retain their white color, relative peak heights of spectral lines did shift, but no gaps in the spectrum occurred. Spectra taken at 50% with 30 minutes intervals coincided. Differences between the new and the older Philips lamp were noticeable, but not really significant.

Dimming of metal halide lamps

NASA Technical Reports Server (NTRS)

Schurer, Kees

1994-01-01

We ran some tests on the effect of dimming of metal halide (MH) lamps upon the stability and the spectral quality of the light output. Lamps used were a new Philips lamp HPI-T 250W, a similar Philips lamp with a few thousand burning hours and a new Osram lamp HQI-T 250W/D. The ballast was a BBC type DJ 250/2KS, the starter a BAS TORGI type MZN 250 SE and the dimmer an Elstrom Control System type ERHQ-T 250. Power was derived from a Philips stabilizer, type PE 1602. Lamp output was monitored with a PAR meter. Spectra were taken at 100% and at 50% output as measured with the PAR meter. Lamps were allowed to stabilize at any setting for 30 minutes before measurements were made. Lamp manufacturers advise against dimming for fear of poor stability and intolerable changes of the spectrum. However, none of the lamps showed a decrease in stability, no flicker or wandering of the discharge, and the changes of the spectrum were not negligible, but certainly not dramatic. Lamps of either manufacture retain their white color, relative peak heights of spectral lines did shift, but no gaps in the spectrum occurred. Spectra taken at 50% with 30 minutes intervals coincided. Differences between the new and the older Philips lamp were noticeable, but not really significant.

Jacketed lamp bulb envelope

DOEpatents

MacLennan, Donald A.; Turner, Brian P.; Gitsevich, Aleksandr; Bass, Gary K.; Dolan, James T.; Kipling, Kent; Kirkpatrick, Douglas A.; Leng, Yongzhang; Levin, Izrail; Roy, Robert J.; Shanks, Bruce; Smith, Malcolm; Trimble, William C.; Tsai, Peter

2001-01-01

A jacketed lamp bulb envelope includes a ceramic cup having an open end and a partially closed end, the partially closed end defining an aperture, a lamp bulb positioned inside the ceramic cup abutting the aperture, and a reflective ceramic material at least partially covering a portion of the bulb not abutting the aperture. The reflective ceramic material may substantially fill an interior volume of the ceramic cup not occupied by the bulb. The ceramic cup may include a structural feature for aiding in alignment of the jacketed lamp bulb envelope in a lamp. The ceramic cup may include an external flange about a periphery thereof. One example of a jacketed lamp bulb envelope includes a ceramic cup having an open end and a closed end, a ceramic washer covering the open end of the ceramic cup, the washer defining an aperture therethrough, a lamp bulb positioned inside the ceramic cup abutting the aperture, and a reflective ceramic material filling an interior volume of the ceramic cup not occupied by the bulb. A method of packing a jacketed lamp bulb envelope of the type comprising a ceramic cup with a lamp bulb disposed therein includes the steps of filling the ceramic cup with a flowable slurry of reflective material, and applying centrifugal force to the cup to pack the reflective material therein.

Optimal flash rate and duty cycle for flashing visual indicators.

NASA Technical Reports Server (NTRS)

Markowitz, J.

1971-01-01

This experiment examined the ability of observers to determine, as quickly as possible, whether a visual indicator was steadily on or flashing. Six flash rates (periods) were combined factorially with three duty cycles (on-off ratios) to define 18 ?types' of intermittent signals. Experimental sessions were divided into six runs of 100 trials, each run utilizing one of the six flash rates. On any given trial in a run, the probability of a steady signal occurring was 0.5 and the probability of a flashing signal occurring was 0.5. A different duty cycle was employed daily for each experimental session. In all, 400 trials were devoted to each of the flash rates at each duty cycle. Accuracy and latency of response were the dependent variables of interest. The results show that the observers view the light for an interval of time appropriate to the expected flash rate and duty cycle; whether they judge the light to be steady or intermittent depends upon whether the light is extinguished during the predetermined waiting period. Adoption of this temporal criterion delays responding in comparison to those tasks involving responses to light onset. The decision or response criteria held by the observers are also sensitive to the parameters of the flashing light: observers become increasingly willing to call a flashing light ?steady' as flash duration increases.

49 CFR 393.9 - Lamps operable, prohibition of obstructions of lamps and reflectors.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 5 2013-10-01 2013-10-01 false Lamps operable, prohibition of obstructions of lamps and reflectors. 393.9 Section 393.9 Transportation Other Regulations Relating to Transportation... SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and...

49 CFR 393.9 - Lamps operable, prohibition of obstructions of lamps and reflectors.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 5 2011-10-01 2011-10-01 false Lamps operable, prohibition of obstructions of lamps and reflectors. 393.9 Section 393.9 Transportation Other Regulations Relating to Transportation... SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and...

49 CFR 393.9 - Lamps operable, prohibition of obstructions of lamps and reflectors.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 5 2014-10-01 2014-10-01 false Lamps operable, prohibition of obstructions of lamps and reflectors. 393.9 Section 393.9 Transportation Other Regulations Relating to Transportation... SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and...

49 CFR 393.9 - Lamps operable, prohibition of obstructions of lamps and reflectors.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 5 2012-10-01 2012-10-01 false Lamps operable, prohibition of obstructions of lamps and reflectors. 393.9 Section 393.9 Transportation Other Regulations Relating to Transportation... SAFETY REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and...

Physics of Incandescent Lamp Burnout

ERIC Educational Resources Information Center

Gluck, Paul; King, John

2008-01-01

Incandescent lamps with tungsten filaments have been in use for about a century while being gradually replaced by fluorescent lamps; in another generation both will quite probably be largely replaced by light-emitting diodes. Incandescent lamps (simply called "lamps" in what follows) burn out after a lifetime that depends mostly on the temperature…

NAND FLASH Radiation Tolerant Intelligent Memory Stack (RTIMS FLASH)

NASA Astrophysics Data System (ADS)

Sellier, Charles; Wang, Pierre

2014-08-01

The NAND Flash Radiation Tolerant and Intelligent Memory Stack (RTIMS FLASH) is a User's Friendly, Plug-and- Play and Radiation Protected high density NAND Flash Memory. It provides a very high density, radiation hardened by design and non-volatile memory module suitable for all space applications such as commercial or scientific geo-stationary missions, earth observation, navigation, manned space vehicles and deep space scientific exploration. The Intelligent Memory Module embeds a very high density of non-volatile NAND Flash memory and one Intelligent Flash Memory Controller (FMC). The FMC provides the module with a full protection against the radiation effects such as SEL, SEFI and SEU. It's also granting the module with bad block immunity as well as high level service functions that will benefit to the user's applications.

10 CFR 429.40 - Candelabra base incandescent lamps and intermediate base incandescent lamps.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 3 2013-01-01 2013-01-01 false Candelabra base incandescent lamps and intermediate base....40 Candelabra base incandescent lamps and intermediate base incandescent lamps. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to candelabra base...

10 CFR 429.40 - Candelabra base incandescent lamps and intermediate base incandescent lamps.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 3 2012-01-01 2012-01-01 false Candelabra base incandescent lamps and intermediate base....40 Candelabra base incandescent lamps and intermediate base incandescent lamps. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to candelabra base...

49 CFR 393.9 - Lamps operable, prohibition of obstructions of lamps and reflectors.

Code of Federal Regulations, 2010 CFR

2010-10-01

... (Continued) FEDERAL MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER... Electrical Wiring § 393.9 Lamps operable, prohibition of obstructions of lamps and reflectors. (a) All lamps... any part of the load, or its covering by dirt, or other added vehicle or work equipment, or otherwise...

Physics of Incandescent Lamp Burnout

NASA Astrophysics Data System (ADS)

Gluck, Paul; King, John

2008-01-01

Incandescent lamps with tungsten filaments have been in use for about a century while being gradually replaced by fluorescent lamps; in another generation both will quite probably be largely replaced by light-emitting diodes. Incandescent lamps (simply called lamps in what follows) burn out after a lifetime that depends mostly on the temperature of the filament and hence the applied voltage. A full-term project (about 100 hours) on lamp burnout was carried out by two students in 1965 and has been briefly described. Many aspects of the physics of lamps have been dealt with in articles that have appeared in this journal, in the American Journal of Physics, and in Physics Education.2,3

SEP-Kr and SEP-Xe in Lunar Ilmenite and the Ar/Kr/Xe Ratio in the Solar Wind

NASA Astrophysics Data System (ADS)

Wieler, R.; Baur, H.; Signer, P.

1992-07-01

We analyzed all five noble gases in an ilmenite sample from lunar soil 71501 by closed system stepped etching (CSSE), thus extending our CSSE studies of solar noble gases (Wieler et al., 1986; Benkert et al., 1988) to Kr and Xe. He, Ne, Ar isotopes: We observe the familiar presence of two solar noble gas components: step 1 shows ^4He/^3He = 2250, ^20Ne/^22Ne = 13.8, and ^36Ar/^38Ar=5.46. The first two ratios are essentially identical to modern solar wind values (SWC; Geiss, 1973), indicating an isotopically unfractionated SW noble gas reservoir in lunar ilmenite. The Ne data-points of later steps fall on a straight line and reach the SEP-Ne point (^20Ne/^22Ne = 11.3). The slope of this line indicates mass dependent fractionation between SW-Ne and SEP-Ne. SEP-He (^4He/^3He = 4650 +-100) and SEP-Ar (^36Ar/^38Ar = 4.89+-0.05) are also observed (latter two numbers slightly revised compared to Wieler et al., 1992). Kr, Xe isotopes: Kr in those two steps that release pure SW-Ne is very slightly lighter than atmospheric Kr (^86Kr/^84Kr = 0.3041; see also Wieler et al., 1992). We interpret this to be SW-Kr in soil 71501. Steps containing (isotopically heavier) SEP-Ne likewise release heavier Kr, interpreted accordingly as SEP-Kr (^86Kr/^84Kr = 0.323). Similarly, a light Xe component is released first (SW-Xe, ^136Xe/^132Xe = 0.3003), followed by heavier SEP-Xe (^136Xe/^132Xe = 0.319). The data are consistent with both Kr and Xe in SW and SEP components to be related by mass fractionation. The relation first proposed by Benkert et al. (1988) between a ratio R(m(sub)2,m(sub)1) of two isotopes with masses m(sub)2>m(sub)1 in SW and SEP now holds for all five noble gases: (R(sub)SW-R(sub)SEP)/R(sub)SW = (2+-0.13)*(m(sub)2- m(sub)1)/m(sub)2. Since m(sub)2~m(sub)1, this relation may also be written as: R(sub)SEP/R(sub)SW ~ (m(sub)1/m(sub)2)^2 (Geiss and Bochsler, 1991). Element ratios: ^4He/^36Ar and ^20Ne/^36Ar rise from values several times below SWC to essentially SWC ratios in

Retail Lamps Study 3.1: Dimming, Flicker, and Power Quality Characteristics of LED A Lamps

DOE Office of Scientific and Technical Information (OSTI.GOV)

Royer, Michael P.; Poplawski, Michael E.; Brown, Charles C.

2014-12-01

To date, all three reports in the retail lamps series have focused on basic performance parameters, such as lumen output, efficacy, and color quality. This report goes a step further, examining the photoelectric characteristics (i.e., dimming and flicker) of a subset of lamps from CALiPER Retails Lamps Study 3. Specifically, this report focuses on the dimming, power quality, and flicker characteristics of 14 LED A lamps, as controlled by four different retail-available dimmers. The results demonstrate notable variation across the various lamps, but little variation between the four dimmers. Overall, the LED lamps: ~tended to have higher relative light outputmore » compared to the incandescent and halogen benchmark at the same dimmer output signal (RMS voltage). The lamps’ dimming curves (i.e., the relationship between control signal and relative light output) ranged from linear to very similar to the square-law curve typical of an incandescent lamp. ~generally exhibited symmetrical behavior—the same dimming curve—when measured proceeding from maximum to minimum or minimum to maximum control signal. ~mostly dimmed below 10% of full light output, with some exceptions for specific lamp and dimmer combinations ~exhibited a range of flicker characteristics, with many comparing favorably to the level typical of a magnetically-ballasted fluorescent lamp through at least a majority of the dimming range. ~ always exceeded the relative (normalized) efficacy over the dimming range of the benchmark lamps, which rapidly decline in efficacy when they are dimmed. This report generally does not attempt to rank the performance of one product compared to another, but instead focuses on the collective performance of the group versus conventional incandescent or halogen lamps, the performance of which is likely to be the baseline for a majority of consumers. Undoubtedly, some LED lamps perform better—or more similar to conventional lamps—than others. Some perform desirably

Synchronized Electronic Shutter System (SESS) for Thermal Nondestructive Evaluation

NASA Technical Reports Server (NTRS)

Zalameda, Joseph N.

2001-01-01

The purpose of this paper is to describe a new method for thermal nondestructive evaluation. This method uses a synchronized electronic shutter system (SESS) to remove the heat lamp's influence on the thermal data during and after flash heating. There are two main concerns when using flash heating. The first concern is during the flash when the photons are reflected back into the camera. This tends to saturate the detectors and potentially introduces unknown and uncorrectable errors when curve fitting the data to a model. To address this, an electronically controlled shutter was placed over the infrared camera lens. Before firing the flash lamps, the shutter is opened to acquire the necessary background data for offset calibration. During flash heating, the shutter is closed to prevent the photons from the high intensity flash from saturating the camera's detectors. The second concern is after the flash heating where the lamps radiate heat after firing. This residual cooling introduces an unwanted transient thermal response into the data. To remove this residual effect, a shutter was placed over the flash lamps to block the infrared heat radiating from the flash head after heating. This helped to remove the transient contribution of the flash. The flash lamp shutters were synchronized electronically with the camera shutter. Results are given comparing the use of the thermal inspection with and without the shutter system.

FLASH Interface; a GUI for managing runtime parameters in FLASH simulations

NASA Astrophysics Data System (ADS)

Walker, Christopher; Tzeferacos, Petros; Weide, Klaus; Lamb, Donald; Flocke, Norbert; Feister, Scott

2017-10-01

We present FLASH Interface, a novel graphical user interface (GUI) for managing runtime parameters in simulations performed with the FLASH code. FLASH Interface supports full text search of available parameters; provides descriptions of each parameter's role and function; allows for the filtering of parameters based on categories; performs input validation; and maintains all comments and non-parameter information already present in existing parameter files. The GUI can be used to edit existing parameter files or generate new ones. FLASH Interface is open source and was implemented with the Electron framework, making it available on Mac OSX, Windows, and Linux operating systems. The new interface lowers the entry barrier for new FLASH users and provides an easy-to-use tool for experienced FLASH simulators. U.S. Department of Energy (DOE), NNSA ASC/Alliances Center for Astrophysical Thermonuclear Flashes, U.S. DOE NNSA ASC through the Argonne Institute for Computing in Science, U.S. National Science Foundation.

Flash Platform Examination

DTIC Science & Technology

2011-03-01

than would be performed in software”[108]. Uro Tinic, one of the Flash player’s engineers, further clarifies exactly what Flash player 10 hardware...www.adobe.com/products/flashplayer/features/ (Access date: 28 Sep 2009). [109] Uro , T. What Does GPU Acceleration Mean? (online), http...133] Shorten, A. (2009), Design to Development: Flash Catalyst to Flash Builder, In Proceedings of Adobe Max 2009, Los Angeles, CA. 142 DRDC

Production of pure 133mXe for CTBTO

NASA Astrophysics Data System (ADS)

Peräjärvi, K.; Eronen, T.; Gorelov, D.; Hakala, J.; Jokinen, A.; Kettunen, H.; Kolhinen, V.; Laitinen, M.; Moore, I. D.; Penttilä, H.; Rissanen, J.; Saastamoinen, A.; Toivonen, H.; Turunen, J.; Äystö, J.

2014-01-01

Underground nuclear weapon detonations release gaseous species into the atmosphere. The most interesting isotopes/isomers from the detection point of view are 131mXe, 133mXe, 133Xe and 135Xe. We have developed a method that employs high-precision Penning trap mass spectrometry at the JYFLTRAP facility, the University of Jyväskylä, to produce pure calibration samples of these isotopes/isomers. Among developments this work required a new mass resolution record of a few parts-per-million. Here the status and future plans of the project are reviewed.

I-Xe Dating: Comparison of I-Xe and Pb-Pb Ages of Richardton Chondrules and Separated Mineral Phases

NASA Technical Reports Server (NTRS)

Pravdivtseva, O. V.; Amelin, Y.; Hohenberg, C. M.; Meshik, A. P.

2002-01-01

I-Xe and Pb-Pb ages of individual Richardton chondrules and different mineral phases were compared in order to test the absolute I-Xe age normalization. Additional information is contained in the original extended abstract.

Flashes and Floaters.

PubMed

Sharma, Priya; Sridhar, Jayanth; Mehta, Sonia

2015-09-01

Flashes and floaters are common ocular complaints. Flashes refer to aberrations of light that are seen in a patient's field of gaze. The flashes can be of varying sizes, colors, frequency, and durations, depending on the cause. Floaters are another common visual phenomenon caused by particles or debris in the vitreous gel of the eye that cause shadows and thus visual changes, especially against bright backgrounds and in brightly lit environments. Flashes and floaters can occur individually or together. This article discusses common causes of flashes and floaters to help with the triaging and management of these patients. Copyright © 2015 Elsevier Inc. All rights reserved.

Temperature-Ramped 129Xe Spin-Exchange Optical Pumping

PubMed Central

2015-01-01

We describe temperature-ramped spin-exchange optical pumping (TR-SEOP) in an automated high-throughput batch-mode 129Xe hyperpolarizer utilizing three key temperature regimes: (i) “hot”—where the 129Xe hyperpolarization rate is maximal, (ii) “warm”—where the 129Xe hyperpolarization approaches unity, and (iii) “cool”—where hyperpolarized 129Xe gas is transferred into a Tedlar bag with low Rb content (<5 ng per ∼1 L dose) suitable for human imaging applications. Unlike with the conventional approach of batch-mode SEOP, here all three temperature regimes may be operated under continuous high-power (170 W) laser irradiation, and hyperpolarized 129Xe gas is delivered without the need for a cryocollection step. The variable-temperature approach increased the SEOP rate by more than 2-fold compared to the constant-temperature polarization rate (e.g., giving effective values for the exponential buildup constant γSEOP of 62.5 ± 3.7 × 10–3 min–1 vs 29.9 ± 1.2 × 10–3 min–1) while achieving nearly the same maximum %PXe value (88.0 ± 0.8% vs 90.1% ± 0.8%, for a 500 Torr (67 kPa) Xe cell loading—corresponding to nuclear magnetic resonance/magnetic resonance imaging (NMR/MRI) enhancements of ∼3.1 × 105 and ∼2.32 × 108 at the relevant fields for clinical imaging and HP 129Xe production of 3 T and 4 mT, respectively); moreover, the intercycle “dead” time was also significantly decreased. The higher-throughput TR-SEOP approach can be implemented without sacrificing the level of 129Xe hyperpolarization or the experimental stability for automation—making this approach beneficial for improving the overall 129Xe production rate in clinical settings. PMID:25008290

Photoionization and Photofragmentation of the Endohedral Xe C60+ Molecular Ion

NASA Astrophysics Data System (ADS)

Aryal, Nagendra Bahadur

An experimental study of photoionization and fragmentation of the Xe C 60+ endohedral molecular ion is presented in the photon energy range of the well-known Xe 4d giant resonance, and evidence of redistribution of the Xe 4d oscillator strength in photon energy due to multipath interference is reported. Experiments were conducted at undulator beamline 10.0.1 of the Advanced Light Source (ALS) using the merged-beams technique. Prior to these measurements, macroscopic samples containing endohedral Xe C60 were prepared using a setup developed at the ALS. Endohedral Xe C60 yields as high as 2.5x10 -4 were synthesized and a pure Xe C60+ ion beam current of up to 5.5 pA was obtained for the merged-beams experiments. Cross sections were measured in the photon energy range 60 - 150 eV in 0.5 eV steps for single, double, and triple photoionization of endohedral Xe C 60+ accompanied by the loss of n pairs of carbon atoms yielding Xe C60-2n2+ (n = 0, 1), Xe C60-2n 3+ (n = 0, 1, 2, 3), and Xe C584+ photoion products. Reference absolute cross-section measurements were made for empty C60+ for the corresponding reaction channels. The spectroscopic measurements with Xe C60+ were placed onto an absolute scale by normalization to the reference cross sections for C60+ in ranges of photon energies where the Xe 4d contributions were negligible. Results for single photoionization and fragmentation of Xe C60+ show no evidence of the presence of the caged Xe atom. The measurements of double and triple photoionization with fragmentation of Xe C60+ exhibit prominent signatures of the Xe 4d resonance and together account for 6.6 +/- 1.5 of the total Xe 4d oscillator strength of 10. Compared to that for a free Xe atom, the Xe oscillator strength in Xe C60+ is redistributed in photon energy due to multipath interference of outgoing Xe 4d photoelectron waves that may be transmitted or reflected by the spherical C60+ molecular cage, yielding so-called confinement resonances. The experimental

Evaluation of GOES encoder lamps

NASA Technical Reports Server (NTRS)

Viehmann, W.; Helmold, N.

1983-01-01

Aging characteristics and life expectancies of flight quality, tungsten filament, encoder lamps are similar to those of 'commercial' grade gas filled lamps of similar construction, filament material and filament temperature. The aging and final failure by filament burnout are caused by single crystal growth over large portions of the filament with the concomitant development of facets and notches resulting in reduction of cross section and mechanical weakening of the filament. The life expectancy of presently produced lamps is about one year at their nominal operating voltage of five volts dc. At 4.5 volts, it is about two years. These life times are considerably shorter, and the degradation rates of lamp current and light flux are considerably higher, than were observed in the laboratory and in orbit on lamps of the same type manufactured more than a decade ago. It is speculated that the filaments of these earlier lamps contained a crystallization retarding dopant, possibly thorium oxide. To obtain the desired life expectancy of or = to four years in present lamps, operating voltages of or = to four volts dc would be required.

About 129Xe ∗ in meteoritic nanodiamonds

NASA Astrophysics Data System (ADS)

Fisenko, A. V.; Semjonova, L. F.

2008-08-01

The analysis of excess 129Xe in meteoritic nanodiamonds and the kinetics of its release during stepwise pyrolysis allow to suggest that (1) in the solar nebula 129I atoms were adsorbed onto nanodiamond grains and (or) chemisorbed by forming covalent bonds with carbon atoms. Most 129I atoms existed in a surface connected state, but a minor amount of them was in nanopores of the grains. At radioactive decay of 129I the formed 129Xe ( 129Xe ∗) was trapped by diamond grains due to nuclear recoil. (2) During thermal metamorphism or aqueous alteration, the surface-sited 129I atoms were basically lost. On the basis of these assumptions and calculated concentrations of 129Xe ∗ in meteoritic nanodiamonds it is shown that the minimum closing time of the I-Xe system for meteorites of different chemical classes and low petrologic types may be about one million years relative to the minimally thermally metamorphized CO3 meteorite ALHA 77307. With increasing metamorphic grade the closing time of the I-Xe system increases and can range up to several ten millions years. This tendency is in agreement with an onion-shell model of structure and cooling history of meteorite parent bodies where the temperature increases in the direction from surface to center of the asteroids.

Recoil distance lifetime measurements in 122,124Xe

NASA Astrophysics Data System (ADS)

Govil, I. M.; Kumar, A.; Iyer, H.; Li, H.; Garg, U.; Ghugre, S. S.; Johnson, T.; Kaczarowski, R.; Kharraja, B.; Naguleswaran, S.; Walpe, J. C.

1998-02-01

Lifetimes of the lower-excited states in 122,124Xe are measured using the recoil-distance Doppler-shift technique. The reactions 110Pd(16O,4n)122Xe and 110Pd(18O,4n)124Xe at a beam energy of 66 MeV were used for this experiment. The lifetimes of the 2+, 4+, 6+, and 8+ states of the ground state band were extracted using the computer code LIFETIME including the corrections due to the side feeding and the nuclear deorientation effects. The lifetime of the 2+ state in 122Xe agrees with the recoil distance method (RDM) measurements but for the 124Xe it does not agree with the RDM measurements but agrees with the Coulomb-excitation experiment. The measured B(E2) values for both the nuclei are compared with the standard algebraic and the multishell models.

NMR of laser-polarized 129Xe in blood foam

NASA Technical Reports Server (NTRS)

Tseng, C. H.; Peled, S.; Nascimben, L.; Oteiza, E.; Walsworth, R. L.; Jolesz, F. A.

1997-01-01

Laser-polarized 129Xe dissolved in a foam preparation of fresh human blood was investigated. The NMR signal of 129Xe dissolved in blood was enhanced by creating a foam in which the dissolved 129Xe exchanged with a large reservoir of gaseous laser-polarized 129Xe. The dissolved 129Xe T1 in this system was found to be significantly shorter in oxygenated blood than in deoxygenated blood. The T1 of 129Xe dissolved in oxygenated blood foam was found to be approximately 21 (+/-5) s, and in deoxygenated blood foam to be greater than 40 s. To understand the oxygenation trend, T1 measurements were also made on plasma and hemoglobin foam preparations. The measurement technique using a foam gas-liquid exchange interface may also be useful for studying foam coarsening and other liquid physical properties.

New constraints on Xe incorporation mechanisms in olivine from first-principles calculations

NASA Astrophysics Data System (ADS)

Crépisson, Céline; Blanchard, Marc; Lazzeri, Michele; Balan, Etienne; Sanloup, Chrystèle

2018-02-01

Storage of Xe at depth in silicate minerals has recently been proposed to explain the low Xe abundance in the Earth's and Mars' atmospheres compared to other noble gases (the so-called 'Missing Xenon' issue). Evidences for incorporation, and thus reactivity of Xe in olivine at high pressure and high temperature are based on variations in cell parameters and the appearance of a new Raman band. To constrain the, so far only hypothetical, Xe incorporation mechanism in olivine, we theoretically investigated models of Xe-bearing olivine using density functional theory. Three types of incorporation mechanisms are tested: Xe for Si and Xe for Mg substitutions, and interstitial Xe. Xe for Si substitution, implying an oxidation of Xe, is found to be the only mechanism consistent with experimental observations, leading to an increase of cell parameter a and the appearance of a new Raman band around 720-750 cm-1 associated with Xesbnd O stretching vibrations. Raman spectroscopy makes it possible to identify Xe incorporation site, even at low Xe content, due to high Xe polarizability. An estimation of Xe content in olivine, based on present work and previous in situ experimental results, shows that up to 0.4 at.% Xe could be stored in olivine at depth.

49 CFR 393.25 - Requirements for lamps other than head lamps.

Code of Federal Regulations, 2010 CFR

2010-10-01

... booms, backhoes, and winches) prevents compliance with this paragraph by any required lamp, an auxiliary... SAE J845—Optical Warning Devices for Authorized Emergency, Maintenance and Service Vehicles, May 1997... Authorized Emergency, Maintenance and Service Vehicles, January 2005. Amber gaseous discharge warning lamps...

49 CFR 393.25 - Requirements for lamps other than head lamps.

Code of Federal Regulations, 2011 CFR

2011-10-01

... booms, backhoes, and winches) prevents compliance with this paragraph by any required lamp, an auxiliary... SAE J845—Optical Warning Devices for Authorized Emergency, Maintenance and Service Vehicles, May 1997... Authorized Emergency, Maintenance and Service Vehicles, January 2005. Amber gaseous discharge warning lamps...

49 CFR 393.25 - Requirements for lamps other than head lamps.

Code of Federal Regulations, 2013 CFR

2013-10-01

... booms, backhoes, and winches) prevents compliance with this paragraph by any required lamp, an auxiliary... SAE J845—Optical Warning Devices for Authorized Emergency, Maintenance and Service Vehicles, May 1997... Authorized Emergency, Maintenance and Service Vehicles, January 2005. Amber gaseous discharge warning lamps...

49 CFR 393.25 - Requirements for lamps other than head lamps.

Code of Federal Regulations, 2014 CFR

2014-10-01

... booms, backhoes, and winches) prevents compliance with this paragraph by any required lamp, an auxiliary... SAE J845—Optical Warning Devices for Authorized Emergency, Maintenance and Service Vehicles, May 1997... Authorized Emergency, Maintenance and Service Vehicles, January 2005. Amber gaseous discharge warning lamps...

49 CFR 393.25 - Requirements for lamps other than head lamps.

Code of Federal Regulations, 2012 CFR

2012-10-01

... booms, backhoes, and winches) prevents compliance with this paragraph by any required lamp, an auxiliary... SAE J845—Optical Warning Devices for Authorized Emergency, Maintenance and Service Vehicles, May 1997... Authorized Emergency, Maintenance and Service Vehicles, January 2005. Amber gaseous discharge warning lamps...

49 CFR 234.221 - Lamp voltage.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Lamp voltage. 234.221 Section 234.221..., Inspection, and Testing Maintenance Standards § 234.221 Lamp voltage. The voltage at each lamp shall be maintained at not less than 85 percent of the prescribed rating for the lamp. ...

49 CFR 234.221 - Lamp voltage.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Lamp voltage. 234.221 Section 234.221..., Inspection, and Testing Maintenance Standards § 234.221 Lamp voltage. The voltage at each lamp shall be maintained at not less than 85 percent of the prescribed rating for the lamp. ...

Flash protection controller

DOEpatents

Galbraith, L.K.

1979-12-07

A controller provides a high voltage to maintain an electro-optic shutter in a transparent condition until a flash of light which would be harmful to personnel is sensed by a phototransistor. The controller then shorts the shutter to ground to minimize light transmission to the user and maintains light transmission at the pre-flash level for a predetermined time to allow the flash to subside. A log converter and differential trigger circuit keep the controller from being triggered by other light flashes which are not dangerous.

Flash protection controller

DOEpatents

Galbraith, Lee K.

1981-01-01

A controller provides a high voltage to maintain an electro-optic shutter in a transparent condition until a flash of light which would be harmful to personnel is sensed by a phototransistor. The controller then shorts the shutter to ground to minimize light transmission to the user and maintains light transmission at the pre-flash level for a predetermined time to allow the flash to subside. A log converter and differential trigger circuit keep the controller from being triggered by other light flashes which are not dangerous.

High-j neutron excitations outside 136Xe

NASA Astrophysics Data System (ADS)

Talwar, R.; Kay, B. P.; Mitchell, A. J.; Adachi, S.; Entwisle, J. P.; Fujita, Y.; Gey, G.; Noji, S.; Ong, H. J.; Schiffer, J. P.; Tamii, A.

2017-08-01

The ν 0 h9 /2 and ν 0 i13 /2 strength at 137Xe, a single neutron outside the N =82 shell closure, has been determined using the 136Xe(α ,3He)137Xe reaction carried out at 100 MeV. We confirm the recent observation of the second 13 /2+ state and reassess previous data on the 9 /2- states, obtaining spectroscopic factors. These new data provide additional constraints on predictions of the same single-neutron excitations at 133Sn.

Lunar Impact Flash Locations

NASA Technical Reports Server (NTRS)

Moser, D. E.; Suggs, R. M.; Kupferschmidt, L.; Feldman, J.

2015-01-01

A bright impact flash detected by the NASA Lunar Impact Monitoring Program in March 2013 brought into focus the importance of determining the impact flash location. A process for locating the impact flash, and presumably its associated crater, was developed using commercially available software tools. The process was successfully applied to the March 2013 impact flash and put into production on an additional 300 impact flashes. The goal today: provide a description of the geolocation technique developed.

Photodynamic Therapy for Cancer Cells Using a Flash Wave Light Xenon Lamp

NASA Astrophysics Data System (ADS)

Kimura, Makoto; Kashikura, Kasumi; Yokoi, Satomi; Koiwa, Yumiko; Tokuoka, Yoshikazu; Kawashima, Norimichi

We determined photodynamic therapy (PDT) efficacy using a flash wave (FW) and a continuous wave (CW) light, of which the fluence rate was 70 W/cm2, for murine thymic lymphoma cells (EL-4) cultivated in vitro. The irradiation frequency and the pulse width of the FW light were in the range of 1-32 Hz and less than one millisecond, respectively. 5-Aminolevulinic acid-induced protoporphyrin IX (ALA-PpIX) was used as a photosensitizer. When EL-4 with ALA administration was irradiated by the light for 4 h (irradiation fluence: 1.0J/cm2), the survival rate of EL-4 by the FW light was lower than that by the CW light, except for the FW light with irradiation frequency of 32 Hz, and decreased gradually with decreasing irradiation frequency. Moreover, the FW light, especially at lower irradiation frequency, was superior to the CW light for the generation of singlet oxygen in an aqueous PpIX solution. Therefore, thehigher PDT efficacy for EL-4 of the FW light would be caused by the greater generation of singlet oxygen in the cells.

40 CFR 273.5 - Applicability-lamps.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 28 2013-07-01 2013-07-01 false Applicability-lamps. 273.5 Section 273...) STANDARDS FOR UNIVERSAL WASTE MANAGEMENT General § 273.5 Applicability—lamps. (a) Lamps covered under this part 273. The requirements of this part apply to persons managing lamps as described in § 273.9, except...

40 CFR 273.5 - Applicability-lamps.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 27 2011-07-01 2011-07-01 false Applicability-lamps. 273.5 Section 273...) STANDARDS FOR UNIVERSAL WASTE MANAGEMENT General § 273.5 Applicability—lamps. (a) Lamps covered under this part 273. The requirements of this part apply to persons managing lamps as described in § 273.9, except...

40 CFR 273.5 - Applicability-lamps.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Applicability-lamps. 273.5 Section 273...) STANDARDS FOR UNIVERSAL WASTE MANAGEMENT General § 273.5 Applicability—lamps. (a) Lamps covered under this part 273. The requirements of this part apply to persons managing lamps as described in § 273.9, except...

40 CFR 273.5 - Applicability-lamps.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 28 2012-07-01 2012-07-01 false Applicability-lamps. 273.5 Section 273...) STANDARDS FOR UNIVERSAL WASTE MANAGEMENT General § 273.5 Applicability—lamps. (a) Lamps covered under this part 273. The requirements of this part apply to persons managing lamps as described in § 273.9, except...

40 CFR 273.5 - Applicability-lamps.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 27 2014-07-01 2014-07-01 false Applicability-lamps. 273.5 Section 273...) STANDARDS FOR UNIVERSAL WASTE MANAGEMENT General § 273.5 Applicability—lamps. (a) Lamps covered under this part 273. The requirements of this part apply to persons managing lamps as described in § 273.9, except...

Experimental ion mobility measurements in Xe-CF4 mixtures

NASA Astrophysics Data System (ADS)

Cortez, A. F. V.; Kaja, M. A.; Escada, J.; Santos, M. A. G.; Veenhof, R.; Neves, P. N. B.; Santos, F. P.; Borges, F. I. G. M.; Conde, C. A. N.

2018-04-01

In this paper we present the results of the ion mobility measurements made in gaseous mixtures of xenon with carbon tetrafluoride (Xe-CF4) for pressures ranging from 6 to 10 Torr (8-10.6 mbar) and for low reduced electric fields in the 10 to 25 Td range (2.4-6.1 kVṡcm‑1ṡbar‑1), at room temperature. The time-of-arrival spectra revealed one or two peaks depending on the gas relative abundances, which were attributed to CF3+ and to Xe2+ ions. However, for Xe concentrations above 60%, only one peak remains (Xe2+). The reduced mobilities obtained from the peak centroid of the time-of-arrival spectra are presented for Xe concentrations in the 5%-95% range.

Stable Chloro- and Bromoxenate Cage Anions; [X3(XeO3)3]3- and [X4(XeO3)4]4- (X = Cl or Br).

PubMed

Goettel, James T; Haensch, Veit G; Schrobilgen, Gary J

2017-06-28

The number of isolable compounds which contain different noble-gas-element bonds is limited for xenon and even more so for krypton. Examples of Xe-Cl bonds are rare, and prior to this work, no Xe-Br bonded compound had been isolated in macroscopic quantities. The syntheses, isolation, and characterization of the first compounds to contain Xe-Br bonds and their chlorine analogues are described in the present work. The reactions of XeO 3 with [N(CH 3 ) 4 ]Br and [N(C 2 H 5 ) 4 ]Br have provided two bromoxenate salts, [N(C 2 H 5 ) 4 ] 3 [Br 3 (XeO 3 ) 3 ] and [N(CH 3 ) 4 ] 4 [Br 4 (XeO 3 ) 4 ], in which the cage anions have Xe-Br bond lengths that range from 3.0838(3) to 3.3181(8) Å. The isostructural chloroxenate anions (Xe-Cl bond lengths, 2.9316(2) to 3.101(4) Å) were synthesized by analogy with their bromine analogues. The bromo- and chloroxenate salts are stable in the atmosphere at room temperature and were characterized in the solid state by Raman spectroscopy and low-temperature single-crystal X-ray diffraction, and in the gas phase by quantum-chemical calculations. They are the only known examples of cage anions that contain a noble-gas element. The Xe-Br and Xe-Cl bonds are very weakly covalent and can be viewed as σ-hole interactions, similar to those encountered in halogen bonding. However, the halogen atoms in these cases are valence electron lone pair donors, and the σ* Xe-O orbitals are lone pair acceptors.

Predictions for multiplicities and flow harmonics in 5.44 TeV Xe+Xe collisions at the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Eskola, K. J.; Niemi, H.; Paatelainen, R.; Tuominen, K.

2018-03-01

We present the event-by-event next-to-leading-order perturbative-QCD + saturation + viscous hydrodynamics (EKRT) model predictions for the centrality dependence of the charged hadron multiplicity in the pseudorapidity interval |η |≤0.5 , and for the centrality dependence of the charged hadron flow harmonics vn{2 } obtained from two-particle cumulants, in √{sN N}=5.44 TeV Xe+Xe collisions at the CERN Large Hadron Collider. Our prediction for the 0-5 % central charged multiplicity is d Nch/d η =1218 ±46 . We also predict vn{2 } in Xe+Xe collisions to increase more slowly from central towards peripheral collisions than those in a Pb+Pb system. We find that at 10 ,⋯,50 % centralities v2{2 } is smaller and v3{2 } is larger than in the Pb+Pb system while v4{2 } is of the same magnitude in both systems. We also find that the ratio of flow harmonics in Xe+Xe collisions and in Pb+Pb collisions shows a slight sensitivity to the temperature dependence of the shear-viscosity-to-entropy ratio. As we discuss here, the new nuclear mass-number systematics especially in the flow harmonics serves as a welcome further constraint for describing the space-time evolution of a heavy-ion system and for determining the shear viscosity and other transport properties of strongly interacting matter.

Wood's lamp illumination (image)

MedlinePlus

A Wood's lamp emits ultraviolet light and can be a diagnostic aid in determining if someone has a fungal ... is an infection on the area where the Wood's lamp is illuminating, the area will fluoresce. Normally ...

Slit-lamp exam (image)

MedlinePlus

A slit-lamp, which is a specialized magnifying microscope, is used to examine the structures of the eye (including the cornea, iris, vitreous, and retina). The slit-lamp is used to examine, treat (with a laser), ...

Improved search for two-neutrino double electron capture on 124Xe and 126Xe using particle identification in XMASS-I

NASA Astrophysics Data System (ADS)

Xmass Collaboration; Abe, K.; Hiraide, K.; Ichimura, K.; Kishimoto, Y.; Kobayashi, K.; Kobayashi, M.; Moriyama, S.; Nakahata, M.; Norita, T.; Ogawa, H.; Sato, K.; Sekiya, H.; Takachio, O.; Takeda, A.; Tasaka, S.; Yamashita, M.; Yang, B. S.; Kim, N. Y.; Kim, Y. D.; Itow, Y.; Kanzawa, K.; Kegasa, R.; Masuda, K.; Takiya, H.; Fushimi, K.; Kanzaki, G.; Martens, K.; Suzuki, Y.; Xu, B. D.; Fujita, R.; Hosokawa, K.; Miuchi, K.; Oka, N.; Takeuchi, Y.; Kim, Y. H.; Lee, K. B.; Lee, M. K.; Fukuda, Y.; Miyasaka, M.; Nishijima, K.; Nakamura, S.

2018-05-01

We conducted an improved search for the simultaneous capture of two K-shell electrons on the ^{124}Xe and ^{126}Xe nuclei with emission of two neutrinos using 800.0 days of data from the XMASS-I detector. A novel method to discriminate γ-ray/X-ray or double electron capture signals from β-ray background using scintillation time profiles was developed for this search. No significant signal was found when fitting the observed energy spectra with the expected signal and background. Therefore, we set the most stringent lower limits on the half-lives at 2.1 × 10^{22} and 1.9 × 10^{22} years for ^{124}Xe and ^{126}Xe, respectively, with 90% confidence level. These limits improve upon previously reported values by a factor of 4.5.

Flash!

NASA Astrophysics Data System (ADS)

Schilling, Govert

2002-04-01

About three times a day our sky flashes with a powerful pulse of gamma ray bursts (GRB), invisible to human eyes but not to astronomers' instruments. The sources of this intense radiation are likely to be emitting, within the span of seconds or minutes, more energy than the sun will in its entire 10 billion years of life. Where these bursts originate, and how they come to have such incredible energies, is a mystery scientists have been trying to solve for three decades. The phenomenon has resisted study -- the flashes come from random directions in space and vanish without trace -- until very recently. In what could be called a cinematic conflation of Flash Gordon and The Hunt for Red October, Govert Schilling's Flash!: The Hunt for the Biggest Explosions in the Universe describes the exciting and ever-changing field of GRB research. Based on interviews with leading scientists, Flash! provides an insider's account of the scientific challenges involved in unravelling the enigmatic nature of GRBs. A science writer who has followed the drama from the very start, Schilling describes the ambition and jealousy, collegiality and competition, triumph and tragedy, that exists among those who have embarked on this recherche. Govert Schilling is a Dutch science writer and astronomy publicist. He is a contributing editor of Sky and Telescope magazine, and regularly writes for the news sections of Science and New Scientist. Schilling is the astronomy writer for de Volkskrant, one of the largest national daily newspapers in The Netherlands, and frequently talks about the Universe on Dutch radio broadcasts. He is the author of more than twenty popular astronomy books, and hundreds of newspaper and magazine articles on astronomy.

Turning on LAMP

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bostedt, Christoph

2014-06-30

Christoph Bostedt, a senior staff scientist at SLAC's Linac Coherent Light Source X-ray laser, provides a sneak peek of a powerful new instrument, called LAMP, that is now available for experiments that probe the atomic and molecular realm. LAMP replaces and updates the first instrument at LCLS, dubbed CAMP, which will be installed at an X-ray laser in Germany.

Turning on LAMP

ScienceCinema

Bostedt, Christoph

2018-01-16

Christoph Bostedt, a senior staff scientist at SLAC's Linac Coherent Light Source X-ray laser, provides a sneak peek of a powerful new instrument, called LAMP, that is now available for experiments that probe the atomic and molecular realm. LAMP replaces and updates the first instrument at LCLS, dubbed CAMP, which will be installed at an X-ray laser in Germany.

Flash fire propensity of materials

NASA Technical Reports Server (NTRS)

Hilado, C. J.; Cumming, H. J.

1977-01-01

Flash fire test results on 86 materials, evaluated using the USF flash fire screening test, are presented. The materials which appear least prone to flash fires are PVC, polyphenylene oxide and sulfide, and polyether and polyaryl sulfone; these did not produce flash fires under these particular test conditions. The principal value of these screening tests at the present time is in identifying materials which appear prone to flash fires, and in identifying which formulations of a generic material are more or less prone to flash fires.

Production of reactive species using vacuum ultraviolet photodissociation as a tool for studying their effects in plasma medicine: simulations and measurements

NASA Astrophysics Data System (ADS)

Ono, Ryo; Tokumitsu, Yusuke; Zen, Shungo; Yonemori, Seiya

2014-11-01

We propose a method for producing OH, H, O, O3, and O2(a1Δg) using the vacuum ultraviolet photodissociation of H2O and O2 as a tool for studying the reaction processes of plasma medicine. For photodissociation, an H2O/He or O2/He mixture flowing in a quartz tube is irradiated by a Xe2 or Kr2 excimer lamp. The effluent can be applied to a target. Simulations show that the Xe2 lamp method can produce OH radicals within 0.1-1 ppm in the effluent at 5 mm from a quartz tube nozzle. This is comparable to those produced by a helium atmospheric-pressure plasma jet (He-APPJ) currently used in plasma medicine. The Xe2 lamp method also produces H atoms of, at most, 6 ppm. In contrast, the maximum O densities produced by the Xe2 and Kr2 lamp methods are 0.15 ppm and 2.5 ppm, respectively; these are much lower than those from He-APPJ (several tens of ppm). Both lamp methods can produce ozone at concentrations above 1000 ppm and O2(a1Δg) at tens of ppm. The validity of the simulations is verified by measuring the O3 and OH densities produced by the Xe2 lamp method using ultraviolet absorption and laser-induced fluorescence. The differences between the measured and simulated densities for O3 and OH are 20% and factors of 3-4, respectively.

Xe-126 Excesses: Monoisotopic Anomalies in Regolith Samples?

NASA Technical Reports Server (NTRS)

Mathew, K. J.; Marti, K.; Levskii, L. K.

2003-01-01

We present new Xe isotopic signatures of Pesyanoe regolith samples which document excesses of 126Xe and we explore the possibility that it formed by low-energy reactions on transient Te-rich coatings.

Half-life of Xe120

NASA Astrophysics Data System (ADS)

Phillips, A. A.; Andreoiu, C.; Ball, G. C.; Bandyopadhyay, D.; Behr, J. A.; Chupp, T. E.; Finlay, P.; Garrett, P. E.; Grinyer, G. F.; Hackman, G.; Hayden, M. E.; Hyland, B.; Nuss-Warren, S. R.; Pearson, M. R.; Schumaker, M. A.; Smith, M. B.; Svensson, C. E.; Tardiff, E. R.; Valiente-Dobón, J. J.; Warner, T.

2006-08-01

We have measured the half-life of Xe120 using a high-purity germanium (HPGe) detector to monitor the 176, 178, and 762 keV γ rays from Xe120 β+ decay. The result, 46±0.6 min, differs significantly from the value 40±1 min reported by Andersson [Ark. Fys. 28, 37 (1964)]. We have also measured the half-lives of Cs120 and I120 to be 60±0.7 s and 82.1±0.6 min, respectively, both of which are consistent with previous measurements.

Vibration-Resistant Support for Halide Lamps

NASA Technical Reports Server (NTRS)

Kiss, J.

1987-01-01

Lamp envelope protected against breakage. Old and new mounts for halide arc lamp sealed in housing with parabolic refector and quartz window. New version supports lamp with compliant garters instead of rigid brazed joint at top and dimensionally unstable finger stock at bottom.

Analysis of XeC1 Emission in a Hollow Cathode Discharge.

DTIC Science & Technology

1981-06-01

excited homopolar molecule, e.g., Xe2 , Hg2 The term exciplex refers to an electronically excited heteropolar complex, e.g., KrF , XeOH , XeCl , which...HCI Products, k9 = 5.4 x 10 cm /sec. (25) Figure 9 summarizes the main energy pathways for XeCI exciplex formation via three body recombination and

Simulations of Xe and U diffusion in UO2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andersson, Anders D.; Vyas, Shyam; Tonks, Michael R.

2012-09-10

Diffusion of xenon (Xe) and uranium (U) in UO{sub 2} is controlled by vacancy mechanisms and under irradiation the formation of mobile vacancy clusters is important. Based on the vacancy and cluster diffusion mechanisms established from density functional theory (DFT) calculations, we derive continuum thermodynamic and diffusion models for Xe and U in UO{sub 2}. In order to capture the effects of irradiation, vacancies (Va) are explicitly coupled to the Xe and U dynamics. Segregation of defects to grain boundaries in UO{sub 2} is described by combining the bulk diffusion model with models of the interaction between Xe atoms andmore » vacancies with grain boundaries, which were derived from atomistic calculations. The diffusion and segregation models were implemented in the MOOSE-Bison-Marmot (MBM) finite element (FEM) framework and the Xe/U redistribution was simulated for a few simple microstructures.« less

47 CFR 17.54 - Rated lamp voltage.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 1 2012-10-01 2012-10-01 false Rated lamp voltage. 17.54 Section 17.54... STRUCTURES Specifications for Obstruction Marking and Lighting of Antenna Structures § 17.54 Rated lamp... lamps used shall correspond to be within 3 percent higher than the voltage across the lamp socket during...

47 CFR 17.54 - Rated lamp voltage.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 1 2014-10-01 2014-10-01 false Rated lamp voltage. 17.54 Section 17.54... STRUCTURES Specifications for Obstruction Marking and Lighting of Antenna Structures § 17.54 Rated lamp... lamps used shall correspond to be within 3 percent higher than the voltage across the lamp socket during...

47 CFR 17.54 - Rated lamp voltage.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 1 2010-10-01 2010-10-01 false Rated lamp voltage. 17.54 Section 17.54... STRUCTURES Specifications for Obstruction Marking and Lighting of Antenna Structures § 17.54 Rated lamp... lamps used shall correspond to be within 3 percent higher than the voltage across the lamp socket during...

47 CFR 17.54 - Rated lamp voltage.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 1 2011-10-01 2011-10-01 false Rated lamp voltage. 17.54 Section 17.54... STRUCTURES Specifications for Obstruction Marking and Lighting of Antenna Structures § 17.54 Rated lamp... lamps used shall correspond to be within 3 percent higher than the voltage across the lamp socket during...

47 CFR 17.54 - Rated lamp voltage.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 1 2013-10-01 2013-10-01 false Rated lamp voltage. 17.54 Section 17.54... STRUCTURES Specifications for Obstruction Marking and Lighting of Antenna Structures § 17.54 Rated lamp... lamps used shall correspond to be within 3 percent higher than the voltage across the lamp socket during...

Max Tech and Beyond: Fluorescent Lamps

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scholand, Michael

2012-04-01

Fluorescent lamps are the most widely used artificial light source today, responsible for approximately 70% of the lumens delivered to our living spaces globally. The technology was originally commercialized in the 1930's, and manufacturers have been steadily improving the efficacy of these lamps over the years through modifications to the phosphors, cathodes, fill-gas, operating frequency, tube diameter and other design attributes. The most efficient commercially available fluorescent lamp is the 25 Watt T5 lamp. This lamp operates at 114-116 lumens per watt while also providing good color rendering and more than 20,000 hours of operating life. Industry experts interviewed indicatedmore » that while this lamp is the most efficient in the market today, there is still a further 10 to 14% of potential improvements that may be introduced to the market over the next 2 to 5 years. These improvements include further developments in phosphors, fill-gas, cathode coatings and ultraviolet (UV) reflective glass coatings. The commercialization of these technology improvements will combine to bring about efficacy improvements that will push the technology up to a maximum 125 to 130 lumens per watt. One critical issue raised by researchers that may present a barrier to the realization of these improvements is the fact that technology investment in fluorescent lamps is being reduced in order to prioritize research into light emitting diodes (LEDs) and ceramic metal halide high intensity discharge (HID) lamps. Thus, it is uncertain whether these potential efficacy improvements will be developed, patented and commercialized. The emphasis for premium efficacy will continue to focus on T5 lamps, which are expected to continue to be marketed along with the T8 lamp. Industry experts highlighted the fact that an advantage of the T5 lamp is the fact that it is 40% smaller and yet provides an equivalent lumen output to that of a T8 or T12 lamp. Due to its smaller form factor, the T5

COS/FUV Mapping of Stray PtNe Lamp Light Through FCA

NASA Astrophysics Data System (ADS)

Oliveira, Cristina

2010-09-01

order.LAMP2 with CURRENT=LOW is used in all of these visits. In addition, at each position, one exposure with LAMP1 CURRENT=MED is also taken with the G130M/1055 setting, which leads to total counts in 10 sec more than a factor of 10 below the 600,000 limit. This exposure is used so that the ratio of LAMP1/MED to LAMP2/LOW can be calculated for the FCA at each position {in conjunction with the data obtained in visits 11, 12, and 13; see below}. In addition, the G130M/1055 exposures with LAMP1/MED and LAMP2/LOW will be used to determine if the lamp spot size is changing at each position.Depending on the total counts estimated for each setting, either a typical wave exposure is taken or special flash commands are used. Details are given in each visit.Exposures obtained with LAMP1/CURRENT=LOW are expected to have a 20% smaller count rate than exposures obtained with LAMP1/CURRENT=MED. Exposures obtained with LAMP2/CURRENT=MED are expected to have count rates similar to those obtained with LAMP1/CURRENT=MED, and exposures obtained with LAMP2/CURRENT=LOW are expected to have a count rate which is 1/7 of that obtainedwith LAMP2/CURRENT=MED.VISIT 10 OBTAINS LAMP1/CURRENT=MED+ LOW SPECTRA AT ALL THE M SETTINGS USED IN THIS PROGRAM, AT THE NOMINAL POSITION {0.0"}.VISIT 11 OBTAINS LAMP2/CURRENT=MED SPECTRA AT ALL THE M SETTINGS USED IN THIS PROGRAM, AT THE NOMINAL POSITION {0.0"}.VISIT 12 OBTAINS LAMP2/CURRENT=LOW SPECTRA AT ALL THE M SETTINGS USED IN THIS PROGRAM, AT THE NOMINAL POSITION {0.0"}.VISIT 13 OBTAINS LAMP1/CURRENT=MED, LOW AND LAMP2/CURRENT=MED, LOW SPECTRA AT ALL OF THE L SETTINGS USED IN THIS PROGRAM, AT THE NOMINAL POSITION {0.0"}.THE GOAL OF THESE VISITS IS TO DETERMINE THE RATIOS OF THE DIFFERENT LAMP SETTINGS AT DIFFERENT WAVELENGTHS, TO HELP IN ANALYZING THE DATA OBTAINED IN VISITS WHERE ONLY LAMP2/LOW IS USED.ALSO, THESE DATA WILL BE USED TO PREDICT WHAT THE COUNTS WOULD BE WITH G140L/1280/LAMP1/MED AT THE +6.0" POSITION {VIS6N, WHERE LAMP2/LOW IS USED}. THESE

Daily Physical Activity and Hot Flashes in the Study of Women's Health Across the Nation FLASHES Study

PubMed Central

Gibson, Carolyn; Matthews, Karen; Thurston, Rebecca

2014-01-01

Objective To examine the role of physical activity in menopausal hot flashes. Competing models conceptualize physical activity as a risk or protective factor for hot flashes. Few studies have examined this relationship prospectively using physiologic measures of hot flashes and physical activity. Design Over two 48 hour-periods, 51 participants wore a physiologic hot flash monitor and activity monitor, and reported their hot flashes in an electronic diary. Physiologic hot flashes, reported hot flashes and reported hot flashes without physiological corroboration were related to activity changes using hierarchical generalized linear modeling, adjusting for potential confounders. Setting Community. Patients Midlife women. Interventions None. Main Outcome Measures Physiologically-detected hot flashes and reported hot flashes with and without physiologic corroboration. Results Hot flash reports without physiologic corroboration were more likely after activity increases (OR 1.04, 95% CI: 1.00-1.10, p=.01), particularly among women with higher levels of depressive symptoms (interaction p=.02). No other types of hot flashes were related to physical activity. Conclusion Acute increases in physical activity were associated with increased reporting of hot flashes lacking physiologic corroboration, particularly among women with depressive symptoms. Clinicians should consider the role of symptom perception and reporting in relations between physical activity and hot flashes. PMID:24491454

Xe isotope detection and discrimination using beta spectroscopy with coincident gamma spectroscopy

NASA Astrophysics Data System (ADS)

Reeder, P. L.; Bowyer, T. W.

1998-02-01

Beta spectroscopic techniques show promise of significant improvements for a beta-gamma coincidence counter that is part of a system for analyzing Xe automatically separated from air. The previously developed counting system for 131mXe, 133mXe, 133gXe, and 135gXe can be enhanced to give additional discrimination between these Xe isotopes by using the plastic scintillation sample cell as a beta spectrometer to resolve the conversion electron peaks. The automated system will be a key factor in monitoring the Comprehensive Test Ban Treaty.

Magnetic fluorescent lamp

DOEpatents

Berman, S.M.; Richardson R.W.

1983-12-29

The radiant emission of a mercury-argon discharge in a fluorescent lamp assembly is enhanced by providing means for establishing a magnetic field with lines of force along the path of electron flow through the bulb of the lamp assembly, to provide Zeeman splitting of the ultraviolet spectral line. Optimum results are obtained when the magnetic field strength causes a Zeeman splitting of approximately 1.7 times the thermal line width.

Active Flash: Out-of-core Data Analytics on Flash Storage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boboila, Simona; Kim, Youngjae; Vazhkudai, Sudharshan S

2012-01-01

Next generation science will increasingly come to rely on the ability to perform efficient, on-the-fly analytics of data generated by high-performance computing (HPC) simulations, modeling complex physical phenomena. Scientific computing workflows are stymied by the traditional chaining of simulation and data analysis, creating multiple rounds of redundant reads and writes to the storage system, which grows in cost with the ever-increasing gap between compute and storage speeds in HPC clusters. Recent HPC acquisitions have introduced compute node-local flash storage as a means to alleviate this I/O bottleneck. We propose a novel approach, Active Flash, to expedite data analysis pipelines bymore » migrating to the location of the data, the flash device itself. We argue that Active Flash has the potential to enable true out-of-core data analytics by freeing up both the compute core and the associated main memory. By performing analysis locally, dependence on limited bandwidth to a central storage system is reduced, while allowing this analysis to proceed in parallel with the main application. In addition, offloading work from the host to the more power-efficient controller reduces peak system power usage, which is already in the megawatt range and poses a major barrier to HPC system scalability. We propose an architecture for Active Flash, explore energy and performance trade-offs in moving computation from host to storage, demonstrate the ability of appropriate embedded controllers to perform data analysis and reduction tasks at speeds sufficient for this application, and present a simulation study of Active Flash scheduling policies. These results show the viability of the Active Flash model, and its capability to potentially have a transformative impact on scientific data analysis.« less

Live 129I-129Xe dating

NASA Technical Reports Server (NTRS)

Marti, K.

1986-01-01

A technique of cosmic ray exposure age dating using cosmic ray produced I-129 and Xe-129 components is discussed. The live I-129 - Xe-129 method provides an ideal monitor for cosmic ray flux variations on the 10(7)y - 10(8)y time-scale. It is based on low-energy neutron reactions on Te, and these data, when coupled to those from other methods, may facilitate the detection of complex exposure histories.

Fluorescence Lyman-Alpha Stratospheric Hygrometer (FLASH): application on meteorological balloons, long duration balloons and unmanned aerial vehicles.

NASA Astrophysics Data System (ADS)

Lykov, Alexey; Khaykin, Sergey; Yushkov, Vladimir; Efremov, Denis; Formanyuk, Ivan; Astakhov, Valeriy

The FLASH instrument is based on the fluorescent method, which uses H2O molecules photodissociation at a wavelength lambda=121.6 nm (Lalpha - hydrogen emission) followed by the measurement of the fluorescence of excited OH radicals. The source of Lyman-alpha radiation is a hydrogen discharge lamp while the detector of OH fluorescence at 308 -316 nm is a photomultiplier run in photon counting mode. The intensity of the fluorescent light as well as the instrument readings is directly proportional to the water vapor mixing ratio under stratospheric conditions with negligible oxygen absorption. Initially designed for rocket-borne application, FLASH has evolved into a light-weight balloon sonde (FLASH-B) for measurements in the upper troposphere and stratosphere on board meteorological and small plastic balloons. This configuration has been used in over 100 soundings at numerous tropical mid-latitude and polar locations within various international field campaigns. An airborne version of FLASH instrument is successfully utilized onboard stratospheric M55-Geophysica aircraft and tropospheric airborne laboratory YAK42-Roshydromet. The hygrometer was modified for application onboard stratospheric long-duration balloons (FLASH-LDB version). This version was successfully used onboard CNES super-pressure balloon launched from SSC Esrange in March 2007 and flown during 10 days. Special design for polar long duration balloon PoGOLite was created for testing work during polar day in June 2013. Installation and measurement peculiarities as well as observational results are presented. Observations of water vapour using FLASH-B instrument, being of high quality are rather costly as the payload recovery is often complicated and most of the time impossible. Following the goal to find a cost-efficient solution, FLASH was adapted for use onboard Unmanned Aerial Vehicles (UAV). This solution was only possible thanks to compactness and light-weight (0.5 kg) of FLASH instrument. The

49 CFR 393.11 - Lamps and reflective devices.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 5 2012-10-01 2012-10-01 false Lamps and reflective devices. 393.11 Section 393... ACCESSORIES NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.11 Lamps and reflective devices. (a)(1) Lamps and reflex reflectors. Table 1 specifies the requirements for lamps...

49 CFR 393.11 - Lamps and reflective devices.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 5 2014-10-01 2014-10-01 false Lamps and reflective devices. 393.11 Section 393... ACCESSORIES NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.11 Lamps and reflective devices. (a)(1) Lamps and reflex reflectors. Table 1 specifies the requirements for lamps...

Menopausal hot flashes: Randomness or rhythmicity

NASA Astrophysics Data System (ADS)

Kronenberg, Fredi

1991-10-01

Menopausal hot flashes are episodes of flushing, increased heart rate, skin blood flow and skin temperature, and a sensation of heat. The thermoregulatory and cardiovascular concomitants of hot flashes are associated with peaks in the levels of various hormones and neurotransmitters in the peripheral circulation. Although hot flashes affect about 75% of women, and are the primary reason that women at menopause seek medical attention, the mechanism of hot flashes is still not understood. Hot flashes vary in frequency and intensity both within and between individuals, and have been thought of as occurring randomly. Yet, some women report that their hot flashes are worse at a particular time of day or year. Initial examination of subjects' recordings of their hot flashes showed diurnal patterns of hot flash occurrence. There also seems to be a diurnal rhythm of hot flash intensity. Continuous physiological monitoring of hot flashes is facilitating the analysis of these patterns, which is revealing circadian and ultradian periodicities. The occurrence of hot flashes can be modulated by external and internal factors, including ambient temperature and fever. Rhythms of thermoregulatory and endocrine functions also may influence hot flash patterns. Examination of the interrelationships between the various systems of the body involved in hot flashes, and a multidisciplinary approach to the analysis of hot flash patterns, will aid our understanding of this complex phenomenon.

30 CFR 20.9 - Class 2 lamps.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Class 2 lamps. 20.9 Section 20.9 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MINE LAMPS OTHER THAN STANDARD CAP LAMPS § 20.9 Class 2 lamps. (a) Safety. (1...

46 CFR 167.40-25 - Signaling lamp.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Signaling lamp. 167.40-25 Section 167.40-25 Shipping... Certain Equipment Requirements § 167.40-25 Signaling lamp. Nautical school ships of over 150 gross tons shall be equipped with an efficient signaling lamp. This lamp shall be permanently fixed above the...

46 CFR 167.40-25 - Signaling lamp.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Signaling lamp. 167.40-25 Section 167.40-25 Shipping... Certain Equipment Requirements § 167.40-25 Signaling lamp. Nautical school ships of over 150 gross tons shall be equipped with an efficient signaling lamp. This lamp shall be permanently fixed above the...

46 CFR 167.40-25 - Signaling lamp.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Signaling lamp. 167.40-25 Section 167.40-25 Shipping... Certain Equipment Requirements § 167.40-25 Signaling lamp. Nautical school ships of over 150 gross tons shall be equipped with an efficient signaling lamp. This lamp shall be permanently fixed above the...

46 CFR 167.40-25 - Signaling lamp.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Signaling lamp. 167.40-25 Section 167.40-25 Shipping... Certain Equipment Requirements § 167.40-25 Signaling lamp. Nautical school ships of over 150 gross tons shall be equipped with an efficient signaling lamp. This lamp shall be permanently fixed above the...

46 CFR 167.40-25 - Signaling lamp.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Signaling lamp. 167.40-25 Section 167.40-25 Shipping... Certain Equipment Requirements § 167.40-25 Signaling lamp. Nautical school ships of over 150 gross tons shall be equipped with an efficient signaling lamp. This lamp shall be permanently fixed above the...

LAMPS software

NASA Technical Reports Server (NTRS)

Perkey, D. J.; Kreitzberg, C. W.

1984-01-01

The dynamic prediction model along with its macro-processor capability and data flow system from the Drexel Limited-Area and Mesoscale Prediction System (LAMPS) were converted and recorded for the Perkin-Elmer 3220. The previous version of this model was written for Control Data Corporation 7600 and CRAY-1a computer environment which existed until recently at the National Center for Atmospheric Research. The purpose of this conversion was to prepare LAMPS for porting to computer environments other than that encountered at NCAR. The emphasis was shifted from programming tasks to model simulation and evaluation tests.

30 CFR 57.17010 - Electric lamps.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric lamps. 57.17010 Section 57.17010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....17010 Electric lamps. Individual electric lamps shall be carried for illumination by all persons...

30 CFR 57.17010 - Electric lamps.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric lamps. 57.17010 Section 57.17010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....17010 Electric lamps. Individual electric lamps shall be carried for illumination by all persons...

30 CFR 57.17010 - Electric lamps.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric lamps. 57.17010 Section 57.17010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....17010 Electric lamps. Individual electric lamps shall be carried for illumination by all persons...

30 CFR 57.17010 - Electric lamps.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric lamps. 57.17010 Section 57.17010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....17010 Electric lamps. Individual electric lamps shall be carried for illumination by all persons...

30 CFR 57.17010 - Electric lamps.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric lamps. 57.17010 Section 57.17010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE....17010 Electric lamps. Individual electric lamps shall be carried for illumination by all persons...

Max Tech and Beyond: High-Intensity Discharge Lamps

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scholand, Michael

High-intensity discharge (HID) lamps are most often found in industrial and commercial applications, and are the light source of choice in street and area lighting, and sports stadium illumination. HID lamps are produced in three types - mercury vapor (MV), high pressure sodium (HPS) and metal halide (MH). Of these, MV and MH are considered white-light sources (although the MV exhibits poor color rendering) and HPS produces a yellow-orange color light. A fourth lamp, low-pressure sodium (LPS), is not a HID lamp by definition, but it is used in similar applications and thus is often grouped with HID lamps. Withmore » the notable exception of MV which is comparatively inefficient and in decline in the US from both a sales and installed stock point of view; HPS, LPS and MH all have efficacies over 100 lumens per watt. The figure below presents the efficacy trends over time for commercially available HID lamps and LPS, starting with MV and LPS in 1930's followed by the development of HPS and MH in the 1960's. In HID lamps, light is generated by creating an electric arc between two electrodes in an arc tube. The particles in the arc are partially ionized, making them electrically conductive, and a light-emitting 'plasma' is created. This arc occurs within the arc tube, which for most HID lamps is enclosed within an evacuated outer bulb that thermally isolates and protects the hot arc tube from the surroundings. Unlike a fluorescent lamp that produces visible light through down-converting UV light with phosphors, the arc itself is the light source in an HID lamp, emitting visible radiation that is characteristic of the elements present in the plasma. Thus, the mixture of elements included in the arc tube is one critical factor determining the quality of the light emitted from the lamp, including its correlated color temperature (CCT) and color rendering index (CRI). Similar to fluorescent lamps, HID lamps require a ballast to start and maintain stable operating

Concentration Independent Calibration of β-γ Coincidence Detector Using 131mXe and 133Xe

DOE Office of Scientific and Technical Information (OSTI.GOV)

McIntyre, Justin I.; Cooper, Matthew W.; Carman, April J.

Absolute efficiency calibration of radiometric detectors is frequently difficult and requires careful detector modeling and accurate knowledge of the radioactive source used. In the past we have calibrated the b-g coincidence detector of the Automated Radioxenon Sampler/Analyzer (ARSA) using a variety of sources and techniques which have proven to be less than desirable.[1] A superior technique has been developed that uses the conversion-electron (CE) and x-ray coincidence of 131mXe to provide a more accurate absolute gamma efficiency of the detector. The 131mXe is injected directly into the beta cell of the coincident counting system and no knowledge of absolute sourcemore » strength is required. In addition, 133Xe is used to provide a second independent means to obtain the absolute efficiency calibration. These two data points provide the necessary information for calculating the detector efficiency and can be used in conjunction with other noble gas isotopes to completely characterize and calibrate the ARSA nuclear detector. In this paper we discuss the techniques and results that we have obtained.« less

30 CFR 75.1703-1 - Permissible lamps.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Permissible lamps. 75.1703-1 Section 75.1703-1... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703-1 Permissible lamps. Lamps... this chapter (Bureau of Mines Schedule 6D and Schedule 10C) are approved lamps for the purposes of § 75...

30 CFR 75.1703-1 - Permissible lamps.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Permissible lamps. 75.1703-1 Section 75.1703-1... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703-1 Permissible lamps. Lamps... this chapter (Bureau of Mines Schedule 6D and Schedule 10C) are approved lamps for the purposes of § 75...

30 CFR 75.1703-1 - Permissible lamps.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Permissible lamps. 75.1703-1 Section 75.1703-1... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703-1 Permissible lamps. Lamps... this chapter (Bureau of Mines Schedule 6D and Schedule 10C) are approved lamps for the purposes of § 75...

30 CFR 75.1703-1 - Permissible lamps.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Permissible lamps. 75.1703-1 Section 75.1703-1... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703-1 Permissible lamps. Lamps... this chapter (Bureau of Mines Schedule 6D and Schedule 10C) are approved lamps for the purposes of § 75...

30 CFR 75.1703-1 - Permissible lamps.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Permissible lamps. 75.1703-1 Section 75.1703-1... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703-1 Permissible lamps. Lamps... this chapter (Bureau of Mines Schedule 6D and Schedule 10C) are approved lamps for the purposes of § 75...

Why Flash Type Matters: A Statistical Analysis

NASA Astrophysics Data System (ADS)

Mecikalski, Retha M.; Bitzer, Phillip M.; Carey, Lawrence D.

2017-09-01

While the majority of research only differentiates between intracloud (IC) and cloud-to-ground (CG) flashes, there exists a third flash type, known as hybrid flashes. These flashes have extensive IC components as well as return strokes to ground but are misclassified as CG flashes in current flash type analyses due to the presence of a return stroke. In an effort to show that IC, CG, and hybrid flashes should be separately classified, the two-sample Kolmogorov-Smirnov (KS) test was applied to the flash sizes, flash initiation, and flash propagation altitudes for each of the three flash types. The KS test statistically showed that IC, CG, and hybrid flashes do not have the same parent distributions and thus should be separately classified. Separate classification of hybrid flashes will lead to improved lightning-related research, because unambiguously classified hybrid flashes occur on the same order of magnitude as CG flashes for multicellular storms.

49 CFR 234.221 - Lamp voltage.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Lamp voltage. 234.221 Section 234.221... EMERGENCY NOTIFICATION SYSTEMS Maintenance, Inspection, and Testing Maintenance Standards § 234.221 Lamp voltage. The voltage at each lamp shall be maintained at not less than 85 percent of the prescribed rating...

49 CFR 234.221 - Lamp voltage.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Lamp voltage. 234.221 Section 234.221... EMERGENCY NOTIFICATION SYSTEMS Maintenance, Inspection, and Testing Maintenance Standards § 234.221 Lamp voltage. The voltage at each lamp shall be maintained at not less than 85 percent of the prescribed rating...

49 CFR 234.221 - Lamp voltage.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Lamp voltage. 234.221 Section 234.221... EMERGENCY NOTIFICATION SYSTEMS Maintenance, Inspection, and Testing Maintenance Standards § 234.221 Lamp voltage. The voltage at each lamp shall be maintained at not less than 85 percent of the prescribed rating...

Investigation of Passive Filter for LED Lamp

NASA Astrophysics Data System (ADS)

Sarwono, Edi; Facta, Mochammad; Handoko, Susatyo

2017-04-01

Light Emitting Diode lamp or LED lamp is one of the energy saving lamps nowadays widely used by consumers. However, LED lamp has contained harmonics caused by the rectifier circuit inside the lamp. Harmonics cause a quality problem in power system. As the harmonics present in current or voltage, the waveforms are distorted. Harmonics can lead to overheating in magnetic core of electrical equipments. In this paper, several tests are carried out to investigate the harmonic content of voltage and currents, and also the level of light intensity of the two brands of LED lamps. Measurements in this study are conducted by using HIOKI Power Quality Analyzer 3197. The test results show that the total harmonic distortion or THD of voltage on various brands of LED lamps did not exceed 5% as in compliance to the limit of IEEE standard 519-1992. The largest harmonic voltage is 2.9%, while maximum harmonic current for tested brands of LED lamp is 170.6%. The use of low pass filter in the form of LC filter was proposed. Based on experimental results, the application of LC filter at input side of LED lamp has successfully reduced THD current in the range of 85%-88%.

CALiPER Retail Lamps Study 3.1: Dimming, Flicker, and Power Quality Characteristics of LED A Lamps

DOE Office of Scientific and Technical Information (OSTI.GOV)

none,

2014-12-31

This CALiPER report examines the characteristics of a subset of lamps from CALiPER Retail Lamps Study 3 in more detail. Specifically, it focuses on the dimming, power quality, and flicker characteristics of 14 LED A lamps, as controlled by four different retail-available dimmers.

CALiPER Retail Lamps Study 3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Royer, Michael P.; Beeson, Tracy A.

2014-02-01

The CALiPER program first began investigating LED lamps sold at retail stores in 2010, purchasing 33 products from eight retailers and covering six product categories. The findings revealed a fragmented marketplace, with large disparities in performance of different products, accuracy of manufacturer claims, and offerings from different retail outlets. Although there were some good products, looking back many would not be considered viable competitors to other available options, with too little lumen output, not high enough efficacy, or poor color quality. CALiPER took another look in late 2011purchasing 38 products of five different types from nine retailers and the improvementmore » was marked. Performance was up; retailer claims were more accurate; and the price per lumen and price per unit efficacy were down, although the price per product had not changed much. Nonetheless, there was still plenty of room for improvement, with the performance of LED lamps not yet reaching that of well-established classes of conventional lamps (e.g., 75 W incandescent A19 lamps). Since the second retail lamp study was published in early 2012, there has been substantial progress in all aspects of LED lamps available from retailers. To document this progress, CALiPER again purchased a sample of lamps from retail stores 46 products in total, focusing on A19, PAR30, and MR16 lamps but instead of a random sample, sought to select products to answer specific hypotheses about performance. These hypotheses focused on expanding ranges of LED equivalency, the accuracy of lifetime claims, efficacy and price trends, as well as changes to product designs. Among other results, key findings include: There are now very good LED options to compete with 60 W, 75 W, and 100 W incandescent A19 lamps, and 75 W halogen PAR30 lamps. MR16 lamps have shown less progress, but there are now acceptable alternatives to 35 W, 12 V halogen MR16 lamps and 50 W, 120 V halogen MR16 lamps for some applications

Xe incorporation in crust and upper mantle minerals: new experimental and theoretical evidences

NASA Astrophysics Data System (ADS)

Celine, C.; Sanloup, C.; Blanchard, M.; Lazzeri, M.; Balan, E.; Hudspeth, J.

2017-12-01

Storage of Xe in silicate minerals has been proposed to explain the `Missing Xenon' issue, i.e. the low Xe abundance in the Earth's and Mars' atmospheres compared to other noble gases [1]. However, data about Xe incorporation in minerals remain scarce due to high Xe volatility preventing studies at ambient conditions. Xe incorporations in olivine [2] and quartz [3] have been proposed based on experimental evidences at high pressures and temperatures. Nevertheless, Xe incorporation mechanisms remained so far only hypothetical. We present here new in situ X-ray diffraction data in diamond-anvil cell showing Xe incorporation in widespread silicate minerals of the continental crust (feldspars and quartz) and of the upper mantle (olivine) at relevant pressure and temperature conditions. Significant variations in cell parameters are retrieved in Xe-rich minerals as well as new peaks, implying change in the crystal structures linked to Xe incorporation. Theoretical calculations have been performed (using the density functional theory) to propose Xe incorporation sites able to reproduce experimental observations. In olivine, a Xe for Si substitutions is proposed, with up to 0.4 at% Xe potentially stored in olivine at depth. These new constraints on Xe incorporation at depths in silicate minerals, often neglected, could be crucial in the `Missing Xenon' issue. [1] Anders and Owen (1977) Science 198, 453-465, [2] Sanloup et al. (2011) Geochim. Cosmochim. Acta 75, 6271-6284, [3] Sanloup et al., (2005) Science, 310, 1174-1177

Inductive tuners for microwave driven discharge lamps

DOEpatents

Simpson, James E.

1999-01-01

An RF powered electrodeless lamp utilizing an inductive tuner in the waveguide which couples the RF power to the lamp cavity, for reducing reflected RF power and causing the lamp to operate efficiently.

Mass and Double-Beta-Decay Q Value of Xe136

NASA Astrophysics Data System (ADS)

Redshaw, Matthew; Wingfield, Elizabeth; McDaniel, Joseph; Myers, Edmund G.

2007-02-01

The atomic mass of Xe136 has been measured by comparing cyclotron frequencies of single ions in a Penning trap. The result, with 1 standard deviation uncertainty, is M(Xe136)=135.907 214 484 (11) u. Combined with previous results for the mass of Ba136 [Audi, Wapstra, and Thibault, Nucl. Phys. A 729, 337 (2003)NUPABL0375-947410.1016/j.nuclphysa.2003.11.003], this gives a Q value (M[Xe136]-M[Ba136])c2=2457.83(37)keV, sufficiently precise for ongoing searches for the neutrinoless double-beta decay of Xe136.

Multi- and unisensory visual flash illusions.

PubMed

Courtney, Jon R; Motes, Michael A; Hubbard, Timothy L

2007-01-01

The role of stimulus structure in multisensory and unisensory interactions was examined. When a flash (17 ms) was accompanied by multiple tones (each 7 ms, SOA < or =100 ms) multiple flashes were reported, and this effect has been suggested to reflect the role of stimulus continuity in multisensory interactions. In experiments 1 and 2 we examined if stimulus continuity would affect concurrently presented stimuli. When a relatively longer flash (317 ms) was accompanied by multiple tones (each 7 ms), observers reported perceiving multiple flashes. In experiment 3 we tested whether a flash presented near fixation would induce an illusory flash further in the periphery. One flash (17 ms) presented 5 degrees below fixation was reported as multiple flashes if presented with two flashes (each 17 ms, SOA =100 ms) 2 degrees above fixation. The extent to which these data support a phenomenological continuity principle and whether this principle applies to unisensory perception is discussed.

Two-flash thresholds as a function of flash luminance and area.

DOT National Transportation Integrated Search

1968-09-01

The recent use of strobe lights in aviation suggests the possibility of using temporal patterns of short duration flashes as information-carrying signals. Under night flight conditions, two-flash thresholds were obtained using a two-interval, tempora...

The fundus slit lamp.

PubMed

Gellrich, Marcus-Matthias

2015-01-01

Fundus biomicroscopy with the slit lamp as it is practiced widely nowadays was not established until the 1980-es with the introduction of the Volk lenses +90 and +60D. Thereafter little progress has been made in retinal imaging with the slit lamp. It is the aim of this paper to fully exploit the potential of a video slit lamp for fundus documentation by using easily accessible additions. Suitable still images are easily retrieved from videorecordings of slit lamp examinations. The effects of changements in the slit lamp itself (slit beam and apertures) and its examination equipment (converging lenses from +40 to +90D) on quality and spectrum of fundus images are demonstrated. Imaging software is applied for reconstruction of larger fundus areas in a mosaic pattern (Hugin®) and to perform the flicker test in order to visualize changes in the same fundus area at different points of time (Power Point®). The three lenses +90/+60/+40D are a good choice for imaging the whole spectrum of retinal diseases. Displacement of the oblique slit light can be used to assess changes in the surface profile of the inner retina which occurs e.g. in macular holes or pigment epithelial detachment. The mosaic function in its easiest form (one strip macula adapted to one strip with the optic disc) provides an overview of the posterior pole comparable to a fundus camera's image. A reconstruction of larger fundus areas is feasible for imaging in vitreoretinal surgery or occlusive vessel disease. The flicker test is a fine tool for monitoring progressive glaucoma by changes in the optic disc, and it is also a valuable diagnostic tool in macular disease. Nearly all retinal diseases can be imaged with the slit lamp - irrespective whether they affect the posterior pole, mainly the optic nerve or the macula, the whole retina or only its periphery. Even a basic fundus controlled perimetry is possible. Therefore fundus videography with the slit lamp is a worthwhile approach especially for the

Custom blending of lamp phosphors

NASA Technical Reports Server (NTRS)

Klemm, R. E.

1978-01-01

Spectral output of fluorescent lamps can be precisely adjusted by using computer-assisted analysis for custom blending lamp phosphors. With technique, spectrum of main bank of lamps is measured and stored in computer memory along with emission characteristics of commonly available phosphors. Computer then calculates ratio of green and blue intensities for each phosphor according to manufacturer's specifications and plots them as coordinates on graph. Same ratios are calculated for measured spectrum. Once proper mix is determined, it is applied as coating to fluorescent tubing.

Xe/Kr Selectivity Measurements using AgZ-PAN at Various Temperatures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garn, Troy Gerry; Greenhalgh, Mitchell Randy; Watson, Tony Leroy

2015-05-01

In preparation for planned FY-15 Xe/Kr multi-column testing, a series of experiments were performed to determine the selectivity of Xe over Kr using the silver converted mordenite-polyacrylonitrile (AgZ-PAN) sorbent. Results from these experiments will be used for parameter selection guidelines to define test conditions for Kr gas capture purity evaluations later this year. The currently configured experimental test bed was modified by installing a new cooling apparatus to permit future multi-column testing with independent column temperature control. The modified test bed will allow for multi-column testing to facilitate a Xe separation followed by a Kr separation using engineered form sorbents.more » Selectivity experiments were run at temperatures of 295, 250 and 220 K. Two feed gas compositions of 1000 ppmv Xe, 150 ppmv Kr in either a He or an air balance were used. AgZ-PAN sorbent selectivity was calculated using Xe and Kr capacity determinations. AgZ-PAN sorbent selectivities for Xe over Kr of 72 were calculated at room temperature (295 K) using the feed gas with a He balance and 34 using the feed gas with an air balance. As the test temperatures were decreased the selectivity of Xe over Kr also decreased due to an increase in both Xe and Kr capacities. At 220 K, the sorbent selectivities for Xe over Kr were 22 using the feed gas with a He balance and 28 using the feed gas with an air balance. The selectivity results indicate that AgZ-PAN used in the first column of a multi-column configuration will provide adequate partitioning of Xe from Kr in the tested temperature range to produce a more pure Kr end product for collection.« less

Coordination of XeF2 to calcium and cadmium hexafluorophosphates(V).

PubMed

Bunic, Tina; Tavcar, Gasper; Tramsek, Melita; Zemva, Boris

2006-02-06

[M(XeF2)5](PF6)2 (M = Ca, Cd) complexes were prepared by the reaction of MF2 and XeF2 under pressure of gaseous PF5 in anhydrous HF as solvent. The coordination sphere of the Ca atom consists of nine fluorine atoms: three from two PF6(-) units (one bidentate and one monodentate) and one from each of six XeF2 molecules. The coordination sphere of the Cd atom consists of eight fluorine atoms: one from each of two PF6(-) units and one from each of six XeF2 molecules. Two of the XeF2 ligands about M in each compound are bridging ligands and are each linked to two M, generating infinite (-M-F-Xe-F-M-F-Xe-F-) chains along the b-axis in the Ca salt and along the c-axis in the Cd compound. The Cd2+ cation is smaller and more electronegative than the Ca2+ cation. These differences account for the higher F ligand coordination in the Ca2+ salt and for other structural features that distinguish them. The different stoichiometry of the PF6(-) salts when compared with their AsF6(-) analogues, which have the composition [M(XeF2)4](AsF6)2 (M = Ca, Cd), is in accord with the lower F ligand charge in the AsF6(-) when compared with that in the PF6(-) compound. Indeed, the AsF6(-) ligand charges appear to be similar to those in the XeF2-bridged species.

Exposure reductions associated with introduction of solar lamps to kerosene lamp-using households in Busia County, Kenya.

PubMed

Lam, N L; Muhwezi, G; Isabirye, F; Harrison, K; Ruiz-Mercado, I; Amukoye, E; Mokaya, T; Wambua, M; Bates, M N

2018-03-01

Solar lamps are a clean and potentially cost-effective alternative to polluting kerosene lamps used by millions of families in developing countries. By how much solar lamps actually reduce exposure to pollutants, however, has not been examined. Twenty households using mainly kerosene for lighting were enrolled through a secondary school in Busia County, Kenya. Personal PM 2.5 and CO concentrations were measured on a school pupil and an adult in each household, before and after provision of 3 solar lamps. PM 2.5 concentrations were measured in main living areas, pupils' bedrooms, and kitchens. Usage sensors measured use of kerosene and solar lighting devices. Ninety percent of baseline kerosene lamp use was displaced at 1-month follow-up, corresponding to average PM 2.5 reductions of 61% and 79% in main living areas and pupils' bedrooms, respectively. Average 48-h exposure to PM 2.5 fell from 210 to 104 μg/m 3 (-50%) among adults, and from 132 to 35 μg/m 3 (-73%) among pupils. Solar lamps displaced most kerosene lamp use in at least the short term. If sustained, this could mitigate health impacts of household air pollution in some contexts. Achieving safe levels of exposure for all family members would likely require also addressing use of solid-fuel stoves. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Magnetic Resonance Imaging with laser polarized 129Xe

NASA Astrophysics Data System (ADS)

Swanson, Scott D.; Rosen, Matthew S.; Agranoff, Bernard W.; Coulter, Kevin P.; Welsh, Robert C.; Chupp, Timothy E.

1998-01-01

Magnetic Resonance Imaging with laser-polarized 129Xe can be utilized to trace blood flow and perfusion in tissue for a variety of biomedical applications. Polarized xenon gas introduced in to the lungs dissolves in the blood and is transported to organs such as the brain where it accumulates in the tissue. Spectroscopic studies combined with imaging have been used to produce brain images of 129Xe in the rat head. This work establishes that nuclear polarization produced in the gas phases survives transport to the brain where it may be imaged. Increases in polarization and delivered volume of 129Xe will allow clinical measurements of regional blood flow.

Cell Measurements | Photovoltaic Research | NREL

Science.gov Websites

two tungsten and two Xe lamps along with filters to produce light in nine wavelength regions in fiber filters on four filter wheels; adjustable chopping frequency 1-kW Xe 280 to 1,900 nm 10 nm full width at of Isc in the range of 0 to 2 suns using two lamps and neutral-density filters. If the sample is

Hyperpolarized 129Xe MRI of the Human Lung

PubMed Central

Mugler, John P.; Altes, Talissa A.

2012-01-01

By permitting direct visualization of the airspaces of the lung, MR imaging using hyperpolarized gases provides unique strategies for evaluating pulmonary structure and function. Although the vast majority of research in humans has been performed using hyperpolarized 3He, recent contraction in the supply of 3He and consequent increases in price have turned attention to the alternative agent, hyperpolarized 129Xe. Compared to 3He, 129Xe yields reduced signal due to its smaller magnetic moment. Nonetheless, taking advantage of advances in gas-polarization technology, recent studies in humans using techniques for measuring ventilation, diffusion, and partial pressure of oxygen have demonstrated results for hyperpolarized 129Xe comparable to those previously demonstrated using hyperpolarized 3He. In addition, xenon has the advantage of readily dissolving in lung tissue and blood following inhalation, which makes hyperpolarized 129Xe particularly attractive for exploring certain characteristics of lung function, such as gas exchange and uptake, which cannot be accessed using 3He. Preliminary results from methods for imaging 129Xe dissolved in the human lung suggest that these approaches will provide new opportunities for quantifying relationships among gas delivery, exchange, and transport, and thus show substantial potential to broaden our understanding of lung disease. Finally, recent changes in the commercial landscape of the hyperpolarized-gas field now make it possible for this innovative technology to move beyond the research lab. PMID:23355432

Luminescent Characteristics of a Pulsed Discharge Plasma in Xe-KBr Mixture

NASA Astrophysics Data System (ADS)

Heneral, A. A.; Zhmenyak, Y. V.

2018-03-01

A mixture of xenon with a nontoxic halogen carrier Xe-KBr is used to create a plasma radiation source at the 282-nm transition of the XeBr* molecule excited by a high-voltage pulsed-periodic discharge. The luminescence spectra of the plasma of a longitudinal pulsed-periodic discharge in the Xe-KBr mixture at low pressures are studied experimentally. The most intense UV bands of exciplex XeBr* molecules are recorded in the spectral range of 250-350 nm. The spectral, temporal, and energetic characteristics of the radiation source are presented, as well as the dependence of the XeBr* exciplex molecule formation efficiency on the discharge excitation conditions. The optimal conditions for the excitation of UV radiation in the pulsed-periodic discharge plasma are determined.

Characterization and recovery of mercury from spent fluorescent lamps.

PubMed

Jang, Min; Hong, Seung Mo; Park, Jae K

2005-01-01

Fluorescent lamps rely on mercury as the source of ultraviolet radiation for the production of visible light. Partitioning of mercury among vapor phase, loose phosphor powders produced during breaking and washing steps, glass matrices, phosphor powders attached on the glass and aluminum end caps was examined from simulated laboratory lamp recycling tests for different types of spent and new fluorescent lamps. Mercury concentrations in lamp glasses taken from commercial lamp recyclers were also analyzed for comparison with the simulated results of spent and new lamps of different types. The mercury content of the glass from spent lamps was highly variable depending on the lamp type and manufacturer; the median values of the mercury concentration in glasses for spent 26- (T8) and 38-mm (T12) diameter fluorescent lamps were approximately 30 and 45 microg/g, respectively. The average mercury concentration of samples taken from recycler A was 29.6 microg/g, which was about 64% of median value measured from the spent T12 lamps. Over 94% of total mercury in lamps remained either as a component of phosphor powders attached inside the lamp or in glass matrices. New T12 lamps had a higher partitioning percentage of elemental mercury in the vapor phase (0.17%) than spent T12 lamps (0.04%), while spent lamps had higher partitioning percentages of mercury resided on end-caps and phosphor powders detached from the breaking and washing steps. The TCLP values of simulated all lamp-glasses and samples obtained from recyclers were higher than the limit of LDR standard (0.025 mg/L). After investigating acid treatment and high temperature treatment as mercury reclamation techniques, it was found that heating provided the most effective mercury capture. Although the initial mercury concentrations of individual sample were different, the mercury concentrations after 1 h exposure at 100 degrees C were below 4 mug/g for all samples (i.e., <1% remaining). Therefore, it is recommended that

Xe isotopic constraints on cycling of deep Earth volatiles

NASA Astrophysics Data System (ADS)

Parai, R.; Mukhopadhyay, S.

2017-12-01

The modern deep Earth volatile budget reflects primordial volatiles delivered during accretion, radiogenic ingrowth of volatile species (e.g., 40Ar produced by 40K decay), outgassing in association with mantle processing, and regassing via subduction. The noble gases are unique volatile tracers in that they are chemically inert, but are thought to be trapped within hydrous alteration phases in downwelling lithologies. Noble gases thus provide a tracer of volatile transport between the deep Earth and surface reservoirs. Constraints on the fluxes of noble gases between deep Earth and surface reservoirs over time can accordingly be used to provide insight into temperature conditions at subduction zones, limits on volatile cycling, and the evolving distribution of major volatile species in terrestrial reservoirs over time. Xe isotope systematics in mantle-derived rocks show that 80-90% of the mantle Xe budget is derived from recycling of atmospheric Xe, indicating that atmospheric Xe is retained in subducting slabs beyond depths of magma generation in subduction zones over Earth history. We present an integrated model of Xe cycling between the mantle and atmosphere in association with mantle processing over Earth history. We test a wide variety of outgassing and regassing rates and take the evolution of the atmospheric Xe isotopic composition [e.g., 1] into account. Models in which the deep Earth transitions from a net outgassing to net regassing regime best satisfy Xe isotopic constraints from mantle-derived rocks [2-6]. [1] Avice et al., 2017; Nature Communications, 8; [2] Mukhopadhyay, 2012, Nature 486, 101-104; [3] Parai et al., 2012, EPSL 359-360, 227-239; [4] Parai and Mukhopadhay, 2015, G-cubed 16, 719-735; [5] Peto et al., 2013, EPSL 369-370, 13-23; [6] Tucker et al., 2012, EPSL 355-356, 244-254.

30 CFR 75.1703 - Portable electric lamps.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Portable electric lamps. 75.1703 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703 Portable electric lamps. [Statutory Provisions] Persons underground shall use only permissible electric lamps approved by the...

30 CFR 75.1703 - Portable electric lamps.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Portable electric lamps. 75.1703 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703 Portable electric lamps. [Statutory Provisions] Persons underground shall use only permissible electric lamps approved by the...

30 CFR 75.1703 - Portable electric lamps.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Portable electric lamps. 75.1703 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703 Portable electric lamps. [Statutory Provisions] Persons underground shall use only permissible electric lamps approved by the...

30 CFR 75.1703 - Portable electric lamps.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Portable electric lamps. 75.1703 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703 Portable electric lamps. [Statutory Provisions] Persons underground shall use only permissible electric lamps approved by the...

30 CFR 75.1703 - Portable electric lamps.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Portable electric lamps. 75.1703 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1703 Portable electric lamps. [Statutory Provisions] Persons underground shall use only permissible electric lamps approved by the...

49 CFR 393.23 - Power supply for lamps.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 5 2013-10-01 2013-10-01 false Power supply for lamps. 393.23 Section 393.23... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.23 Power supply for lamps. All required lamps must be powered by the electrical system of the motor vehicle with the...

49 CFR 393.23 - Power supply for lamps.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 5 2012-10-01 2012-10-01 false Power supply for lamps. 393.23 Section 393.23... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.23 Power supply for lamps. All required lamps must be powered by the electrical system of the motor vehicle with the...

Chalcogenide Aerogels as Sorbents for Noble Gases (Xe, Kr)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Subrahmanyam, Kota S.; Spanopoulos, Ioannis; Chun, Jaehun

High surface MoSx and SbSx chalcogels were studied for Xe/Kr gas separation. The intrinsic soft character of the chalcogel framework is a unique property among the large family of porous materials and offers a potential new approach towards the selective separation of Xe over Kr. Among these chalcogels, MoSx shows the highest Xe and Kr uptake, reaching 0.69 mmol g-1 (1.05 mmol cm-3) and 0.28 mmol g-1 (0.42 mmol cm-3) respectively, at 273 K and 1 bar. The corresponding isosteric heat of adsorption at zero coverage (Qst0) is 22.8 and 18.6 kJ mol-1 and both are the highest among themore » selected chalcogels. The IAST (10:90) Xe/Kr selectivity at 273 K for MoSx is 6.0 while for SbSx chalcogels varies in the range 2.0-2.8. The higher formal charge of molybdenum, Mo4+, in MoSx versus that of antimony, Sb3+, in SbSx coupled with its larger atomic size could induce higher polarizability in the MoSx framework and therefore higher Xe/Kr selectivity.« less

Stellar laboratories . VIII. New Zr iv-vii, Xe iv-v, and Xe vii oscillator strengths and the Al, Zr, and Xe abundances in the hot white dwarfs G191-B2B and RE 0503-289

NASA Astrophysics Data System (ADS)

Rauch, T.; Gamrath, S.; Quinet, P.; Löbling, L.; Hoyer, D.; Werner, K.; Kruk, J. W.; Demleitner, M.

2017-03-01

Context. For the spectral analysis of high-resolution and high-signal-to-noise spectra of hot stars, state-of-the-art non-local thermodynamic equilibrium (NLTE) model atmospheres are mandatory. These are strongly dependent on the reliability of the atomic data that is used for their calculation. Aims: To search for zirconium and xenon lines in the ultraviolet (UV) spectra of G191-B2B and RE 0503-289, new Zr iv-vii, Xe iv-v, and Xe vii oscillator strengths were calculated. This allows, for the first time, determination of the Zr abundance in white dwarf (WD) stars and improvement of the Xe abundance determinations. Methods: We calculated Zr iv-vii, Xe iv-v, and Xe vii oscillator strengths to consider radiative and collisional bound-bound transitions of Zr and Xe in our NLTE stellar-atmosphere models for the analysis of their lines exhibited in UV observations of the hot WDs G191-B2B and RE 0503-289. Results: We identified one new Zr iv, 14 new Zr v, and ten new Zr vi lines in the spectrum of RE 0503-289. Zr was detected for the first time in a WD. We measured a Zr abundance of -3.5 ± 0.2 (logarithmic mass fraction, approx. 11 500 times solar). We identified five new Xe vi lines and determined a Xe abundance of -3.9 ± 0.2 (approx. 7500 times solar). We determined a preliminary photospheric Al abundance of -4.3 ± 0.2 (solar) in RE 0503-289. In the spectra of G191-B2B, no Zr line was identified. The strongest Zr iv line (1598.948 Å) in our model gave an upper limit of -5.6 ± 0.3 (approx. 100 times solar). No Xe line was identified in the UV spectrum of G191-B2B and we confirmed the previously determined upper limit of -6.8 ± 0.3 (ten times solar). Conclusions: Precise measurements and calculations of atomic data are a prerequisite for advanced NLTE stellar-atmosphere modeling. Observed Zr iv-vi and Xe vi-vii line profiles in the UV spectrum of RE 0503-289 were simultaneously well reproduced with our newly calculated oscillator strengths. Based on observations

Fluorescent discharge lamp

NASA Technical Reports Server (NTRS)

Mukai, E.; Otsuka, H.; Nomi, K.; Honmo, I.

1982-01-01

A rapidly illuminating fluorescent lamp 1,200 mm long and 32.5 mm in diameter with an interior conducting strip which is compatible with conventional fixtures and ballasts is described. The fluorescent lamp is composed of a linear glass tube, electrodes sealed at both ends, mercury and raregas sealed in the glass tube, a fluorescent substance clad on the inner walls of the glass tube, and a clad conducting strip extending the entire length of the glass tube in the axial direction on the inner surface of the tube.

Flash-Type Discrimination

NASA Technical Reports Server (NTRS)

Koshak, William J.

2010-01-01

This viewgraph presentation describes the significant progress made in the flash-type discrimination algorithm development. The contents include: 1) Highlights of Progress for GLM-R3 Flash-Type discrimination Algorithm Development; 2) Maximum Group Area (MGA) Data; 3) Retrieval Errors from Simulations; and 4) Preliminary Global-scale Retrieval.

Controlling the vapor pressure of a mercury lamp

DOEpatents

Grossman, Mark W.; George, William A.

1988-01-01

The invention described herein discloses a method and apparatus for controlling the Hg vapor pressure within a lamp. This is done by establishing and controlling two temperature zones within the lamp. One zone is colder than the other zone. The first zone is called the cold spot. By controlling the temperature of the cold spot, the Hg vapor pressure within the lamp is controlled. Likewise, by controlling the Hg vapor pressure of the lamp, the intensity and linewidth of the radiation emitted from the lamp is controlled.

High pressure neon arc lamp

DOEpatents

Sze, Robert C.; Bigio, Irving J.

2003-07-15

A high pressure neon arc lamp and method of using the same for photodynamic therapies is provided. The high pressure neon arc lamp includes a housing that encloses a quantity of neon gas pressurized to about 500 Torr to about 22,000 Torr. At each end of the housing the lamp is connected by electrodes and wires to a pulse generator. The pulse generator generates an initial pulse voltage to breakdown the impedance of the neon gas. Then the pulse generator delivers a current through the neon gas to create an electrical arc that emits light having wavelengths from about 620 nanometers to about 645 nanometers. A method for activating a photosensitizer is provided. Initially, a photosensitizer is administered to a patient and allowed time to be absorbed into target cells. Then the high pressure neon arc lamp is used to illuminate the target cells with red light having wavelengths from about 620 nanometers to about 645 nanometers. The red light activates the photosensitizers to start a chain reaction that may involve oxygen free radicals to destroy the target cells. In this manner, a high pressure neon arc lamp that is inexpensive and efficiently generates red light useful in photodynamic therapy is provided.

30 CFR 57.12035 - Weatherproof lamp sockets.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Weatherproof lamp sockets. 57.12035 Section 57.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12035 Weatherproof lamp sockets. Lamp sockets shall be of a weatherproof type...

30 CFR 57.12035 - Weatherproof lamp sockets.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Weatherproof lamp sockets. 57.12035 Section 57.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12035 Weatherproof lamp sockets. Lamp sockets shall be of a weatherproof type...

30 CFR 57.12035 - Weatherproof lamp sockets.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Weatherproof lamp sockets. 57.12035 Section 57.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12035 Weatherproof lamp sockets. Lamp sockets shall be of a weatherproof type...

30 CFR 57.12035 - Weatherproof lamp sockets.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Weatherproof lamp sockets. 57.12035 Section 57.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12035 Weatherproof lamp sockets. Lamp sockets shall be of a weatherproof type...

30 CFR 57.12035 - Weatherproof lamp sockets.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Weatherproof lamp sockets. 57.12035 Section 57.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12035 Weatherproof lamp sockets. Lamp sockets shall be of a weatherproof type...

The October 2014 United States Treasury bond flash crash and the contributory effect of mini flash crashes

PubMed Central

Levine, Zachary S.; Floridi, Luciano

2017-01-01

We investigate the causal uncertainty surrounding the flash crash in the U.S. Treasury bond market on October 15, 2014, and the unresolved concern that no clear link has been identified between the start of the flash crash at 9:33 and the opening of the U.S. equity market at 9:30. We consider the contributory effect of mini flash crashes in equity markets, and find that the number of equity mini flash crashes in the three-minute window between market open and the Treasury Flash Crash was 2.6 times larger than the number experienced in any other three-minute window in the prior ten weekdays. We argue that (a) this statistically significant finding suggests that mini flash crashes in equity markets both predicted and contributed to the October 2014 U.S. Treasury Bond Flash Crash, and (b) mini-flash crashes are important phenomena with negative externalities that deserve much greater scholarly attention. PMID:29091931

Portable lamp with dynamically controlled lighting distribution

DOEpatents

Siminovitch, Michael J.; Page, Erik R.

2001-01-01

A double lamp table or floor lamp lighting system has a pair of compact fluorescent lamps (CFLs) arranged vertically with a reflective septum in between. By selectively turning on one or both of the CFLs, down lighting, up lighting, or both up and down lighting is produced. The control system can also vary the light intensity from each CFL. The reflective septum insures that almost all the light produced by each lamp will be directed into the desired light distribution pattern which is selected and easily changed by the user. Planar compact fluorescent lamps, e.g. circular CFLs, particularly oriented horizontally, are preferable. CFLs provide energy efficiency. The lighting system may be designed for the home, hospitality, office or other environments.

Lamp with a truncated reflector cup

DOEpatents

Li, Ming; Allen, Steven C.; Bazydola, Sarah; Ghiu, Camil-Daniel

2013-10-15

A lamp assembly, and method for making same. The lamp assembly includes first and second truncated reflector cups. The lamp assembly also includes at least one base plate disposed between the first and second truncated reflector cups, and a light engine disposed on a top surface of the at least one base plate. The light engine is configured to emit light to be reflected by one of the first and second truncated reflector cups.

Controlling the vapor pressure of a mercury lamp

DOEpatents

Grossman, M.W.; George, W.A.

1988-05-24

The invention described herein discloses a method and apparatus for controlling the Hg vapor pressure within a lamp. This is done by establishing and controlling two temperature zones within the lamp. One zone is colder than the other zone. The first zone is called the cold spot. By controlling the temperature of the cold spot, the Hg vapor pressure within the lamp is controlled. Likewise, by controlling the Hg vapor pressure of the lamp, the intensity and linewidth of the radiation emitted from the lamp is controlled. 2 figs.

Critical phenomena at a first-order phase transition in a lattice of glow lamps: Experimental findings and analogy to neural activity

NASA Astrophysics Data System (ADS)

Minati, Ludovico; de Candia, Antonio; Scarpetta, Silvia

2016-07-01

Networks of non-linear electronic oscillators have shown potential as physical models of neural dynamics. However, two properties of brain activity, namely, criticality and metastability, remain under-investigated with this approach. Here, we present a simple circuit that exhibits both phenomena. The apparatus consists of a two-dimensional square lattice of capacitively coupled glow (neon) lamps. The dynamics of lamp breakdown (flash) events are controlled by a DC voltage globally connected to all nodes via fixed resistors. Depending on this parameter, two phases having distinct event rate and degree of spatiotemporal order are observed. The transition between them is hysteretic, thus a first-order one, and it is possible to enter a metastability region, wherein, approaching a spinodal point, critical phenomena emerge. Avalanches of events occur according to power-law distributions having exponents ≈3/2 for size and ≈2 for duration, and fractal structure is evident as power-law scaling of the Fano factor. These critical exponents overlap observations in biological neural networks; hence, this circuit may have value as building block to realize corresponding physical models.

10 CFR 429.26 - Fluorescent lamp ballasts.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 3 2014-01-01 2014-01-01 false Fluorescent lamp ballasts. 429.26 Section 429.26 Energy... COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.26 Fluorescent lamp ballasts. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to fluorescent lamp ballasts...

10 CFR 429.26 - Fluorescent lamp ballasts.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 3 2012-01-01 2012-01-01 false Fluorescent lamp ballasts. 429.26 Section 429.26 Energy... COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.26 Fluorescent lamp ballasts. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to fluorescent lamp ballasts...

10 CFR 429.26 - Fluorescent lamp ballasts.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 3 2013-01-01 2013-01-01 false Fluorescent lamp ballasts. 429.26 Section 429.26 Energy... COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.26 Fluorescent lamp ballasts. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to fluorescent lamp ballasts...

Loop-Mediated Isothermal Amplification (LAMP) Signature Identification Software

DOE Office of Scientific and Technical Information (OSTI.GOV)

Torres, C.

2009-03-17

This is an extendable open-source Loop-mediated isothermal AMPlification (LAMP) signature design program called LAVA (LAMP Assay Versatile Analysis). LAVA was created in response to limitations of existing LAMP signature programs.

Mass and Double-Beta-Decay Q Value of {sup 136}Xe

DOE Office of Scientific and Technical Information (OSTI.GOV)

Redshaw, Matthew; Wingfield, Elizabeth; McDaniel, Joseph

The atomic mass of {sup 136}Xe has been measured by comparing cyclotron frequencies of single ions in a Penning trap. The result, with 1 standard deviation uncertainty, is M({sup 136}Xe)=135.907 214 484 (11) u. Combined with previous results for the mass of {sup 136}Ba [Audi, Wapstra, and Thibault, Nucl. Phys. A 729, 337 (2003)], this gives a Q value (M[{sup 136}Xe]-M[{sup 136}Ba])c{sup 2}=2457.83(37) keV, sufficiently precise for ongoing searches for the neutrinoless double-beta decay of {sup 136}Xe.

Dispenser printed electroluminescent lamps on textiles for smart fabric applications

NASA Astrophysics Data System (ADS)

de Vos, Marc; Torah, Russel; Tudor, John

2016-04-01

Flexible electroluminescent (EL) lamps are fabricated onto woven textiles using a novel dispenser printing process. Dispenser printing utilizes pressurized air to deposit ink onto a substrate through a syringe and nozzle. This work demonstrates the first use of this technology to fabricate EL lamps. The luminance of the dispenser printed EL lamps is compared to screen-printed EL lamps, both printed on textile, and also commercial EL lamps on polyurethane film. The dispenser printed lamps are shown to have a 1.5 times higher luminance than the best performing commercially available lamp, and have a comparable performance to the screen-printed lamps.

49 CFR 393.23 - Power supply for lamps.

Code of Federal Regulations, 2014 CFR

2014-10-01

... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.23 Power supply for lamps. All required lamps must be powered by the electrical system of the motor vehicle with the...

49 CFR 230.56 - Water glass lamps.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Water glass lamps. 230.56 Section 230.56... Water Glasses and Gauge Cocks § 230.56 Water glass lamps. All water glasses must be supplied with a suitable lamp properly located to enable the engine crew to easily see the water in the glass. Injectors...

49 CFR 230.56 - Water glass lamps.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Water glass lamps. 230.56 Section 230.56... Water Glasses and Gauge Cocks § 230.56 Water glass lamps. All water glasses must be supplied with a suitable lamp properly located to enable the engine crew to easily see the water in the glass. Injectors...

49 CFR 230.56 - Water glass lamps.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Water glass lamps. 230.56 Section 230.56... Water Glasses and Gauge Cocks § 230.56 Water glass lamps. All water glasses must be supplied with a suitable lamp properly located to enable the engine crew to easily see the water in the glass. Injectors...

49 CFR 230.56 - Water glass lamps.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Water glass lamps. 230.56 Section 230.56... Water Glasses and Gauge Cocks § 230.56 Water glass lamps. All water glasses must be supplied with a suitable lamp properly located to enable the engine crew to easily see the water in the glass. Injectors...

49 CFR 230.56 - Water glass lamps.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Water glass lamps. 230.56 Section 230.56... Water Glasses and Gauge Cocks § 230.56 Water glass lamps. All water glasses must be supplied with a suitable lamp properly located to enable the engine crew to easily see the water in the glass. Injectors...

Nuclear structure studies in highly neutron-deficient (114,116)Xe

NASA Astrophysics Data System (ADS)

Degraaf, James Hendrick

Lifetimes of nuclear states in 114Xe and 116Xe were measured for the first time; these nuclei represent the most neutron-deficient isotopes of xenon for which lifetimes have now been measured. The fusion-evaporation reactions 58Ni(60Ni, 2p)116Xe at 223 MeV beam energy and 58Ni(58Ni, 2p)114Xe at 215 MeV beam energy were used. Lifetimes were measured using the Recoil Distance Method (RDM) with the 8π gamma-ray spectrometer at Chalk River Laboratories. The new measurements of the B(E2;2+/to 0+) strength in these nuclei, coupled with the recent measurements for heavier xenon isotopes, are well described within the framework of the O(6) symmetry limit of the Interacting Boson Approximation. The octupole nature of the negative parity side-band was also studied, and the lifetime measurements indicate a change from a K/approx 3 structure in heavier xenon isotopes to a K/approx 0,/ 1 structure in 114Xe.

Xe adsorption site distributions on Pt(111), Pt(221) and Pt(531)

NASA Astrophysics Data System (ADS)

Gellman, Andrew J.; Baker, L.; Holsclaw, B. S.

2016-04-01

The ideal structures of the Pt(111), Pt(221) and Pt(531) surfaces expose adsorption sites that can be qualitatively described as terrace sites on Pt(111), both step and terrace sites on Pt(221), and kink sites on Pt(531). The real surface structures of these surfaces can be complicated by imperfections such as misorientation, reconstruction and thermal roughening, all of which will influence their distributions of adsorption sites. Xe adsorption sites on the Pt(111), Pt(221) and Pt(531) surfaces have been probed using both photoemission of adsorbed Xe (PAX) and temperature programmed desorption (TPD) of Xe. Both PAX and Xe TPD are sensitive to the adsorption sites of the Xe and serve as complementary means of assessing the distributions of adsorption sites on these three Pt surfaces. The adsorption of Xe is sufficiently sensitive to detect the presence of residual steps on the Pt(111) surface at a density of 1.5% step atoms per Pt atom. On the Pt(221) surface, PAX and Xe TPD reveal adsorption at both terrace and step sites simultaneously. Although the ideal structure of the Pt(531) surface has no well-defined steps or terraces, Xe adsorption indicates that its adsorption sites are best described as a distribution of both step and kink sites with roughly twice as many steps sites as kinks.

Current Regulator For Sodium-Vapor Lamps

NASA Technical Reports Server (NTRS)

Mclyman, W. T.

1989-01-01

Regulating circuit maintains nearly-constant alternating current in sodium-vapor lamp. Regulator part of dc-to-ac inverter circuit used to supply power to street lamp from battery charged by solar-cell array.

Phenomenology of the sound-induced flash illusion.

PubMed

Abadi, Richard V; Murphy, Jonathan S

2014-07-01

Past studies, using pairings of auditory tones and visual flashes, which were static and coincident in space but variable in time, demonstrated errors in judging the temporal patterning of the visual flashes-the sound-induced flash illusion. These errors took one of the two forms: under-reporting (sound-induced fusion) or over-reporting (sound-induced fission) of the flash numbers. Our study had three objectives: to examine the robustness of both illusions and to consider the effects of stimulus set and response bias. To this end, we used an extended range of fixed spatial location flash-tone pairings, examined stimuli that were variable in space and time and measured confidence in judging flash numbers. Our results indicated that the sound-induced flash illusion is a robust percept, a finding underpinned by the confidence measures. Sound-induced fusion was found to be more robust than sound-induced fission and a most likely outcome when high numbers of flashes were incorporated within an incongruent flash-tone pairing. Conversely, sound-induced fission was the most likely outcome for the flash-tone pairing which contained two flashes. Fission was also shown to be strongly driven by stimuli confounds such as categorical boundary conditions (e.g. flash-tone pairings with ≤2 flashes) and compressed response options. These findings suggest whilst both fission and fusion are associated with 'auditory driving', the differences in the occurrence and strength of the two illusions not only reflect the separate neuronal mechanisms underlying audio and visual signal processing, but also the test conditions that have been used to investigate the sound-induced flash illusion.

Photoprotection and photoreception of intraocular lenses under xenon and white LED illumination.

PubMed

Artigas, J M; Navea, A; García-Domene, M C; Artigas, C; Lanzagorta, A

2016-05-01

To analyze the photoprotection and phototransmission that various intraocular lenses (IOLs) provide under the illumination of a xenon (Xe) lamp and white LEDs (light emitting diode). The spectral transmission curves of six representative IOLs were measured using a Perkin-Elmer Lambda 35 UV/VIS spectrometer. Various filtering simulations were performed using a Xe lamp and white LEDs. The spectral emissions of these lamps were measured with an ILT-950 spectroradiometer. The IOLs analyzed primarily show transmission of nearly 100% in the visible spectrum. In the ultraviolet (UV) region, the filters incorporated in the various IOLs did not filter equally, and some of them let an appreciable amount of UV through. The Xe lamp presented a strong emission of ultraviolet A (UVA), and its emission under 300nm was not negligible. The white LED did not present an appreciable emission under 380nm. The cut-off wavelength of most filters is between 380 and 400nm (Physiol Hydriol60C(®), IOLTECH E4T(®), Alcon SA60AT(®), Alcon IQ SN60WF(®)), so that their UV protection is very effective. Nonetheless, the IOL OPHTEC Oculaid(®) contains a filter that, when a Xe lamp is used, lets through up to 20% for 350nm and up to 15% for 300nm, which at this point is ultraviolet B (UVB). The OPHTEC(®) Artisan IOL has a transmission peak below 300nm, which must be taken into account under Xe illumination. White LEDs do not emit energy below 380nm, so no special protection is required in the UV region. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Hyperpolarized (129)Xe T (1) in oxygenated and deoxygenated blood

NASA Technical Reports Server (NTRS)

Albert, M. S.; Balamore, D.; Kacher, D. F.; Venkatesh, A. K.; Jolesz, F. A.

2000-01-01

The viability of the new technique of hyperpolarized (129)Xe MRI (HypX-MRI) for imaging organs other than the lungs depends on whether the spin-lattice relaxation time, T(1), of (129)Xe is sufficiently long in the blood. In previous experiments by the authors, the T(1) was found to be strongly dependent upon the oxygenation of the blood, with T(1) increasing from about 3 s in deoxygenated samples to about 10 s in oxygenated samples. Contrarily, Tseng et al. (J. Magn. Reson. 1997; 126: 79-86) reported extremely long T(1) values deduced from an indirect experiment in which hyperpolarized (129)Xe was used to create a 'blood-foam'. They found that oxygenation decreased T(1). Pivotal to their experiment is the continual and rapid exchange of hyperpolarized (129)Xe between the gas phase (within blood-foam bubbles) and the dissolved phase (in the skin of the bubbles); this necessitated a complicated analysis to extract the T(1) of (129)Xe in blood. In the present study, the experimental design minimizes gas exchange after the initial bolus of hyperpolarized (129)Xe has been bubbled through the sample. This study confirms that oxygenation increases the T(1) of (129)Xe in blood, from about 4 s in freshly drawn venous blood, to about 13 s in blood oxygenated to arterial levels, and also shifts the red blood cell resonance to higher frequency. Copyright 2000 John Wiley & Sons, Ltd. Abbreviations used BOLD blood oxygen level dependent NOE nuclear overhouses effect PO(2) oxygen partial pressure RBC red blood cells RF radio frequency SNR signal-to-noise ratio.

Neutron Inelastic Scattering on 134Xe at En = 5 - 8 MeV

NASA Astrophysics Data System (ADS)

Kidd, Mary; Tornow, Werner; Finch, Sean; Krishichayan, Fnu; Bhike, Megha

2017-09-01

Neutrinoless double-beta decay (0 νββ) studies are both the best way to determine the Majorana nature of the neutrino and determine its effective mass. The two main experiments searching for 0 νββ -decay of 136Xe (Q value = 2457.8 keV) are Kamland-Zen and EXO-200. Though both experiments have enriched 136Xe targets, these targets still contain significant quantities of 134Xe. Recently, a new nuclear level was discovered in 134Xe that decays to the ground state emitting a 2485.7 keV gamma ray. The γ-ray production cross section for this branch was found to be on the order of 10 mb for incident neutron energies of 2.5-4.5 MeV. Here, we have extended the investigation of this level to higher incident neutron energies, and further explore the potential neutron-induced backgrounds on both 134Xe and 136Xe for extended neutron energies. We will report our preliminary results for neutron inelastic scattering on 134Xe in applications to 0 νββ decay searches. NSF PHY-1614348, DE-FG02-97ER41033.

Programming A Molecular Relay for Ultrasensitive Biodetection through 129 Xe NMR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Yanfei; Roose, Benjamin W.; Philbin, John P.

2015-12-21

We reported a supramolecular strategy for detecting specific proteins in complex media by using hyperpolarized 129Xe NMR. A cucurbit[6]uril (CB[6])-based molecular relay was programmed for three sequential equilibrium conditions by designing a two-faced guest (TFG) that initially binds CB[6] and blocks the CB[6]–Xe interaction. Moreover, the protein analyte recruits the TFG and frees CB[6] for Xe binding. TFGs containing CB[6]- and carbonic anhydrase II (CAII)-binding domains were synthesized in one or two steps. X-ray crystallography confirmed TFG binding to Zn 2+ in the deep CAII active-site cleft, which precludes simultaneous CB[6] binding. The molecular relay was reprogrammed to detect avidinmore » by using a different TFG. Finally, Xe binding by CB[6] was detected in buffer and in E. coli cultures expressing CAII through ultrasensitive 129Xe NMR spectroscopy.« less

Statistical Evolution of the Lightning Flash

NASA Astrophysics Data System (ADS)

Zoghzoghy, F. G.; Cohen, M.; Said, R.; Inan, U. S.

2012-12-01

Natural lightning is one of the most fascinating and powerful electrical processes on Earth. To date, the physics behind this natural phenomenon are not fully understood, due primarily to the difficulty of obtaining measurements inside thunderstorms and to the wide range of timescales involved (from nanoseconds to seconds). Our aim is to use accurate lightning geo-location data from the National Lightning Detection Network (NLDN) to study statistical patterns in lightning, taking advantage of the fact that millions of lightning flashes occur around the globe every day. We present two sets of results, one involving the patterns of flashes in a storm, and a second involving the patterns of strokes in a flash. These patterns can provide a surrogate measure of the timescales and the spatial extents of the underlying physical processes. First, we study the timescales of charge buildup inside thunderstorms. We find that, following a lightning flash, the probability of another neighboring flash decreases and takes tens of seconds to recover. We find that this suppression effect is a function of flash type, stroke peak current, cloud-to-ground (CG) stroke multiplicity, and other lightning and geographical parameters. We find that the probabilities of subsequent flashes are more suppressed following oceanic lightning, or following flashes with higher peak currents and/or higher multiplicities (for CG flashes). Second, we use NLDN data to study the evolution of the strokes within a CG flash. A CG flash typically includes multiple return strokes, which can occur in the same channel or in multiple channels within a few kilometers. We cluster NLDN stroke data into flashes and produce the probability density function of subsequent strokes as a function of distance and time-delays relative to the previous stroke. Using this technique, we investigate processes which occur during the CG lightning flash with nanosecond to millisecond timescales. For instance, our results suggest

Frequency Domain Fluorimetry Using a Mercury Vapor Lamp

DTIC Science & Technology

2009-04-07

independence from light scatter and excitation/emission intensity variations in order to extract the sample’s fluorescent lifetime. Mercury vapor lamps ...the modulation amplitude of the lamp , An, via: max 0 1 ( ) sin(2 ) n fluorescence n n n I t B nf tπ θ = ∝ +∑ (8... lamp is estimated by assuming the lamp is emitting as a point source of uniform intensity into the lower hemisphere and has a reflector collecting

Lamp reliability studies for improved satellite rubidium frequency standard

NASA Technical Reports Server (NTRS)

Frueholz, R. P.; Wun-Fogle, M.; Eckert, H. U.; Volk, C. H.; Jones, P. F.

1982-01-01

In response to the premature failure of Rb lamps used in Rb atomic clocks onboard NAVSTAR GPS satellites experimental and theoretical investigations into their failure mechanism were initiated. The primary goal of these studies is the development of an accelerated life test for future GPS lamps. The primary failure mechanism was identified as consumption of the lamp's Rb charge via direct interaction between Rb and the lamp's glass surface. The most effective parameters to accelerate the interaction between the Rb and the glass are felt to be RF excitation power and lamp temperature. Differential scanning calorimetry is used to monitor the consumption of Rb within a lamp as a function of operation time. This technique yielded base line Rb consumption data for GPS lamps operating under normal conditions.

FLASH2: Operation, beamlines, and photon diagnostics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Plönjes, Elke, E-mail: elke.ploenjes@desy.de; Faatz, Bart; Kuhlmann, Marion

2016-07-27

FLASH2, a major extension of the soft X-ray free-electron laser FLASH at DESY, turns FLASH into a multi-user FEL facility. A new undulator line is located in a separate accelerator tunnel and driven additionally by the FLASH linear accelerator. First lasing of FLASH2 was achieved in August 2014 with simultaneous user operation at FLASH1. The new FLASH2 experimental hall offers space for up to six experimental end stations, some of which will be installed permanently. The wide wavelength range spans from 4-60 nm and 0.8 nm in the 5{sup th} harmonic and in the future deep into the water windowmore » in the fundamental. While this is of high interest to users, it is challenging from the beamline instrumentation point of view. Online diagnostics - which are mostly pulse resolved - for beam intensity, position, wavelength, wave front, and pulse length have been to a large extent developed at FLASH(1) and have now been optimized for FLASH2. Pump-probe facilities for XUV-XUV, XUV optical and XUV-THz experiments will complete the FLASH2 user facility.« less

FLASH LIDAR Based Relative Navigation

NASA Technical Reports Server (NTRS)

Brazzel, Jack; Clark, Fred; Milenkovic, Zoran

2014-01-01

Relative navigation remains the most challenging part of spacecraft rendezvous and docking. In recent years, flash LIDARs, have been increasingly selected as the go-to sensors for proximity operations and docking. Flash LIDARS are generally lighter and require less power that scanning Lidars. Flash LIDARs do not have moving parts, and they are capable of tracking multiple targets as well as generating a 3D map of a given target. However, there are some significant drawbacks of Flash Lidars that must be resolved if their use is to be of long-term significance. Overcoming the challenges of Flash LIDARs for navigation-namely, low technology readiness level, lack of historical performance data, target identification, existence of false positives, and performance of vision processing algorithms as intermediaries between the raw sensor data and the Kalman filter-requires a world-class testing facility, such as the Lockheed Martin Space Operations Simulation Center (SOSC). Ground-based testing is a critical step for maturing the next-generation flash LIDAR-based spacecraft relative navigation. This paper will focus on the tests of an integrated relative navigation system conducted at the SOSC in January 2014. The intent of the tests was to characterize and then improve the performance of relative navigation, while addressing many of the flash LIDAR challenges mentioned above. A section on navigation performance and future recommendation completes the discussion.

GraXe, graphene and xenon for neutrinoless double beta decay searches

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gómez-Cadenas, J.J.; Martín-Albo, J.; Monrabal, F.

2012-02-01

We propose a new detector concept, GraXe (to be pronounced as grace), to search for neutrinoless double beta decay in {sup 136}XE. GraXe combines a popular detection medium in rare-event searches, liquid xenon, with a new, background-free material, graphene. In our baseline design of GraXe, a sphere made of graphene-coated titanium mesh and filled with liquid xenon (LXe) enriched in the {sup 136}XE isotope is immersed in a large volume of natural LXe instrumented with photodetectors. Liquid xenon is an excellent scintillator, reasonably transparent to its own light. Graphene is transparent over a large frequency range, and impermeable to themore » xenon. Event position could be deduced from the light pattern detected in the photosensors. External backgrounds would be shielded by the buffer of natural LXe, leaving the ultra-radiopure internal volume virtually free of background. Industrial graphene can be manufactured at a competitive cost to produce the sphere. Enriching xenon in the isotope {sup 136}XE is easy and relatively cheap, and there is already near one ton of enriched xenon available in the world (currently being used by the EXO, KamLAND-Zen and NEXT experiments). All the cryogenic know-how is readily available from the numerous experiments using liquid xenon. An experiment using the GraXe concept appears realistic and affordable in a short time scale, and its physics potential is enormous.« less

30 CFR 75.522-1 - Incandescent and fluorescent lamps.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Incandescent and fluorescent lamps. 75.522-1...-1 Incandescent and fluorescent lamps. (a) Except for areas of a coal mine inby the last open crosscut, incandescent lamps may be used to illuminate underground areas. When incandescent lamps are used...

30 CFR 75.522-1 - Incandescent and fluorescent lamps.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Incandescent and fluorescent lamps. 75.522-1...-1 Incandescent and fluorescent lamps. (a) Except for areas of a coal mine inby the last open crosscut, incandescent lamps may be used to illuminate underground areas. When incandescent lamps are used...

30 CFR 75.522-1 - Incandescent and fluorescent lamps.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Incandescent and fluorescent lamps. 75.522-1...-1 Incandescent and fluorescent lamps. (a) Except for areas of a coal mine inby the last open crosscut, incandescent lamps may be used to illuminate underground areas. When incandescent lamps are used...

30 CFR 75.522-1 - Incandescent and fluorescent lamps.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Incandescent and fluorescent lamps. 75.522-1...-1 Incandescent and fluorescent lamps. (a) Except for areas of a coal mine inby the last open crosscut, incandescent lamps may be used to illuminate underground areas. When incandescent lamps are used...

30 CFR 75.522-1 - Incandescent and fluorescent lamps.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Incandescent and fluorescent lamps. 75.522-1...-1 Incandescent and fluorescent lamps. (a) Except for areas of a coal mine inby the last open crosscut, incandescent lamps may be used to illuminate underground areas. When incandescent lamps are used...

RF driven sulfur lamp having driving electrodes arranged to cool the lamp

DOEpatents

Gabor, George; Orr, Thomas Robert; Greene, Charles Maurice; Crawford, Douglas Gordon; Berman, Samuel Maurice

1998-01-01

A high intensity discharge lamp without mercury is disclosed radiating a selected spectrum of which can be almost entirely in the visible range from an envelope that contains a sulfur containing substance. The lamp utilizes a signal source that generates an excitation signal that is externally coupled to the exterior surface of the envelope to excite the enclosed sulfur containing substance. Various embodiments of the lamp use electrodes adjacent the envelope to couple the excitation signal thereto with the face of the electrodes shaped to complement the shape of the exterior surface of the envelope. Two shapes discussed are spherical and cylindrical. To minimize filamentary discharges each envelope may include an elongated stem affixed to the exterior thereof whereby a rotational subsystem spins the envelope. In yet another embodiment the envelope has a Dewar configuration with two electrodes, one positioned near the external curved side surface of the body, and a second to the inner surface of the hole through the envelope. Further, the envelope may contain a backfill of a selected inert gas to assist in the excitation of lamp with that backfill at a pressure of less than 1 atmosphere, wherein the backfill pressure is directly related to the increase or decrease of peak output and inversely related to the increase and decrease of the emitted spectrum from the envelope. The emitting fill can be less than 6 mg/cc, or at least 2 mg/cc of the envelope of a sulfur containing substance.

Application Summary Report 22: LED MR16 Lamps

DOE Office of Scientific and Technical Information (OSTI.GOV)

Royer, Michael P.

2014-07-23

This report analyzes the independently tested photometric performance of 27 LED MR16 lamps. It describes initial performance based on light output, efficacy, distribution, color quality, electrical characteristics, and form factor, with comparisons to a selection of benchmark halogen MR16s and ENERGY STAR qualification thresholds. Three types of products were targeted. First, CALiPER sought 3000 K lamps with the highest rated lumen output (i.e., at least 500 lm) or a claim of equivalency to a 50 W halogen MR16 or higher. The test results indicate that while the initial performance of LED MR16s has improved across the board, market-available products stillmore » do not produce the lumen output and center beam intensity of typical 50 W halogen MR16 lamps. In fact, most of the 18 lamps in this category had lower lumen output and center beam intensity than a typical 35 W halogen MR16 lamp. Second, CALiPER sought lamps with a CRI of 90 or greater. Only four manufacturers were identified with a product in this category. CALiPER testing confirmed the performance of these lamps, which are a good option for applications where high color fidelity is needed. A vast majority of the LED MR16 lamps have a CRI in the low 80s; this is generally acceptable for ambient lighting, but may not always be acceptable for focal lighting. For typical LED packages, there is a fundamental tradeoff between CRI and efficacy, but the lamps in the high-CRI group in this report still offer comparable performance to the rest of the Series 22 products in other performance areas. Finally, CALiPER sought lamps with a narrow distribution, denoted as a beam angle less than 15°. Five such lamps were purchased. Notably, no lamp was identified as having high lumen output (500 lumens or greater), high CRI (90 or greater), a narrow distribution (15° or less), and an efficacy greater than 60 lm/W. This would be an important achievement for LED MR16s especially if output could reach approximately 700 800

Optimized positioning of autonomous surgical lamps

NASA Astrophysics Data System (ADS)

Teuber, Jörn; Weller, Rene; Kikinis, Ron; Oldhafer, Karl-Jürgen; Lipp, Michael J.; Zachmann, Gabriel

2017-03-01

We consider the problem of finding automatically optimal positions of surgical lamps throughout the whole surgical procedure, where we assume that future lamps could be robotized. We propose a two-tiered optimization technique for the real-time autonomous positioning of those robotized surgical lamps. Typically, finding optimal positions for surgical lamps is a multi-dimensional problem with several, in part conflicting, objectives, such as optimal lighting conditions at every point in time while minimizing the movement of the lamps in order to avoid distractions of the surgeon. Consequently, we use multi-objective optimization (MOO) to find optimal positions in real-time during the entire surgery. Due to the conflicting objectives, there is usually not a single optimal solution for such kinds of problems, but a set of solutions that realizes a Pareto-front. When our algorithm selects a solution from this set it additionally has to consider the individual preferences of the surgeon. This is a highly non-trivial task because the relationship between the solution and the parameters is not obvious. We have developed a novel meta-optimization that considers exactly this challenge. It delivers an easy to understand set of presets for the parameters and allows a balance between the lamp movement and lamp obstruction. This metaoptimization can be pre-computed for different kinds of operations and it then used by our online optimization for the selection of the appropriate Pareto solution. Both optimization approaches use data obtained by a depth camera that captures the surgical site but also the environment around the operating table. We have evaluated our algorithms with data recorded during a real open abdominal surgery. It is available for use for scientific purposes. The results show that our meta-optimization produces viable parameter sets for different parts of an intervention even when trained on a small portion of it.

Acute And Long-Term Bioeffects And Lamp Safety

NASA Astrophysics Data System (ADS)

Andersen, F. Alan

1980-10-01

Knowledge of both acute and chronic biological effects is currently used to evaluate lamp safety. In some cases, a quantitative basis for avoiding exposures greater than a certain value can be stated. In other cases, however, only a qualitative estimate of the hazard is available. In a discussion that uses mercury vapor lamps, tanning booths, and sodium vapor lamps as examples, the interplay between the two types of data leading to an evaluation of lamp safety is described.

MARMOT simulations of Xe segregation to grain boundaries in UO2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andersson, Anders D.; Tonks, Michael; Casillas, Luis

2012-06-20

Diffusion of Xe and U in UO{sub 2} is controlled by vacancy mechanisms and under irradiation the formation of mobile vacancy clusters is important. We derive continuum thermodynamic and diffusion models for Xe and U in UO{sub 2} based on the vacancy and cluster diffusion mechanisms established from recent density functional theory (DFT) calculations. Segregation of defects to grain boundaries in UO{sub 2} is described by combining the diffusion model with models of the interaction between Xe atoms and vacancies with grain boundaries derived from separate atomistic calculations. The diffusion and segregation models are implemented in the MOOSE/MARMOT (MBM) finitemore » element (FEM) framework and we simulate Xe redistribution for a few simple microstructures. In this report we focus on segregation to grain boundaries. The U or vacancy diffusion model as well as the coupled diffusion of vacancies and Xe have also been implemented, but results are not included in this report.« less

128Xe Lifetime Measurement Using the Coulex-Plunger Technique in Inverse Kinematics

NASA Astrophysics Data System (ADS)

Konstantinopoulos, T.; Lagoyannis, A.; Harissopulos, S.; Dewald, A.; Rother, W.; Ilie, G.; Jones, P.; Rakhila, P.; Greenlees, P.; Grahn, T.; Julin, R.; Balabanski, D. L.

2008-05-01

The lifetimes of the lowest collective yrast and non-yrast states in 128Xe were measured in a Coulomb excitation experiment using the recoil distance method (RDM) in inverse kinematics. Hereby, the Cologne plunger apparatus was employed together with the JUROGAM spectrometer. Excited states in 128Xe were populated using a 128Xe beam impinging on a natFe target with E(128Xe)~525 MeV. Recoils were detected by means of an array of solar cells placed at forward angles. Recoil-gated γ-spectra were measured at different plunger distances.

NIR small arms muzzle flash

NASA Astrophysics Data System (ADS)

Montoya, Joseph; Kennerly, Stephen; Rede, Edward

2010-04-01

Utilization of Near-Infrared (NIR) spectral features in a muzzle flash will allow for small arms detection using low cost silicon (Si)-based imagers. Detection of a small arms muzzle flash in a particular wavelength region is dependent on the intensity of that emission, the efficiency of source emission transmission through the atmosphere, and the relative intensity of the background scene. The NIR muzzle flash signature exists in the relatively large Si spectral response wavelength region of 300 nm-1100 nm, which allows for use of commercial-off-the-shelf (COTS) Si-based detectors. The alkali metal origin of the NIR spectral features in the 7.62 × 39-mm round muzzle flash is discussed, and the basis for the spectral bandwidth is examined, using a calculated Voigt profile. This report will introduce a model of the 7.62 × 39-mm NIR muzzle flash signature based on predicted source characteristics. Atmospheric limitations based on NIR spectral regions are investigated in relation to the NIR muzzle flash signature. A simple signal-to-clutter ratio (SCR) metric is used to predict sensor performance based on a model of radiance for the source and solar background and pixel registered image subtraction.

Menopausal Hot Flashes and White Matter Hyperintensities

PubMed Central

Thurston, Rebecca C.; Aizenstein, Howard J.; Derby, Carol A.; Sejdić, Ervin; Maki, Pauline M.

2015-01-01

Objective Hot flashes are the classic menopausal symptom. Emerging data links hot flashes to cardiovascular disease (CVD) risk, yet how hot flashes are related to brain health is poorly understood. We examined the relationship between hot flashes - measured via physiologic monitor and self-report - and white matter hyperintensities (WMH) among midlife women. Methods Twenty midlife women ages 40-60 without clinical CVD, with their uterus and both ovaries, and not taking hormone therapy were recruited. Women underwent 24 hours of ambulatory physiologic and diary hot flash monitoring to quantify hot flashes; magnetic resonance imaging to assess WMH burden; 72 hours of actigraphy and questionnaires to quantify sleep; and a blood draw, questionnaires, and physical measures to quantify demographics and CVD risk factors. Test of a priori hypotheses regarding relations between physiologically-monitored and self-reported wake and sleep hot flashes and WMH were conducted in linear regression models. Results More physiologically-monitored hot flashes during sleep were associated with greater WMH, controlling for age, race, and body mass index [beta(standard error)=.0002 (.0001), p=.03]. Findings persisted controlling for sleep characteristics and additional CVD risk factors. No relations were observed for self-reported hot flashes. Conclusions More physiologically-monitored hot flashes during sleep were associated with greater WMH burden among midlife women free of clinical CVD. Results suggest that relations between hot flashes and CVD risk observed in the periphery may extend to the brain. Future work should consider the unique role of sleep hot flashes in brain health. PMID:26057822

Gun muzzle blast and flash

NASA Astrophysics Data System (ADS)

Klingenberg, Guenter; Heimerl, Joseph M.

A repository of fundamental experimental and analytical data concerning the complex phenomena associated with gun-muzzle blast and flash effects is presented, proceeding from gun muzzle signatures to modern gun-propulsion concepts, interior and transitional ballistics, and characterizations of blast-wave research and muzzle flash. Data are presented in support of a novel hypothesis which explains the ignition of secondary flash and elucidates the means for its suppression. Both chemical and mechanical (often competing) methods of flash suppression are treated. The historical work of Kesslau and Ladenburg is noted, together with French, British, Japanese and American research efforts and current techniques of experimental characterization for gun muzzle phenomena.

XeCl Avalanche discharge laser employing Ar as a diluent

DOEpatents

Sze, Robert C.

1981-01-01

A XeCl avalanche discharge exciplex laser which uses a gaseous lasing starting mixture of: (0.2%-0.4% chlorine donor/2.5%-10% Xe/97.3%-89.6% Ar). The chlorine donor normally comprises HCl but can also comprise CCl.sub.4 BCl.sub.3. Use of Ar as a diluent gas reduces operating pressures over other rare gas halide lasers to near atmospheric pressure, increases output lasing power of the XeCl avalanche discharge laser by 30% to exceed KrF avalanche discharge lasing outputs, and is less expensive to operate.

Imaging Human Brain Perfusion with Inhaled Hyperpolarized 129Xe MR Imaging.

PubMed

Rao, Madhwesha R; Stewart, Neil J; Griffiths, Paul D; Norquay, Graham; Wild, Jim M

2018-02-01

Purpose To evaluate the feasibility of directly imaging perfusion of human brain tissue by using magnetic resonance (MR) imaging with inhaled hyperpolarized xenon 129 ( 129 Xe). Materials and Methods In vivo imaging with 129 Xe was performed in three healthy participants. The combination of a high-yield spin-exchange optical pumping 129 Xe polarizer, custom-built radiofrequency coils, and an optimized gradient-echo MR imaging protocol was used to achieve signal sensitivity sufficient to directly image hyperpolarized 129 Xe dissolved in the human brain. Conventional T1-weighted proton (hydrogen 1 [ 1 H]) images and perfusion images by using arterial spin labeling were obtained for comparison. Results Images of 129 Xe uptake were obtained with a signal-to-noise ratio of 31 ± 9 and demonstrated structural similarities to the gray matter distribution on conventional T1-weighted 1 H images and to perfusion images from arterial spin labeling. Conclusion Hyperpolarized 129 Xe MR imaging is an injection-free means of imaging the perfusion of cerebral tissue. The proposed method images the uptake of inhaled xenon gas to the extravascular brain tissue compartment across the intact blood-brain barrier. This level of sensitivity is not readily available with contemporary MR imaging methods. © RSNA, 2017.

Targeted Molecular Imaging of Cancer Cells Using MS2-Based 129 Xe NMR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jeong, Keunhong; Netirojjanakul, Chawita; Munch, Henrik K.

Targeted, selective, and highly sensitive 129Xe NMR nanoscale biosensors have been synthesized using a spherical MS2 viral capsid, Cryptophane A molecules, and DNA aptamers. The biosensors showed strong binding specificity toward targeted lymphoma cells (Ramos line). Hyperpolarized 129Xe NMR signal contrast and hyper-CEST 129Xe MRI image contrast indicated its promise as highly sensitive hyperpolarized 129Xe NMR nanoscale biosensor for future applications in cancer detection in vivo.

Optima XE Single Wafer High Energy Ion Implanter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Satoh, Shu; Ferrara, Joseph; Bell, Edward

2008-11-03

The Optima XE is the first production worthy single wafer high energy implanter. The new system combines a state-of-art single wafer endstation capable of throughputs in excess of 400 wafers/hour with a production-proven RF linear accelerator technology. Axcelis has been evolving and refining RF Linac technology since the introduction of the NV1000 in 1986. The Optima XE provides production worthy beam currents up to energies of 1.2 MeV for P{sup +}, 2.9 MeV for P{sup ++}, and 1.5 MeV for B{sup +}. Energies as low as 10 keV and tilt angles as high as 45 degrees are also available., allowingmore » the implanter to be used for a wide variety of traditional medium current implants to ensure high equipment utilization. The single wafer endstation provides precise implant angle control across wafer and wafer to wafer. In addition, Optima XE's unique dose control system allows compensation of photoresist outgassing effects without relying on traditional pressure-based methods. We describe the specific features, angle control and dosimetry of the Optima XE and their applications in addressing the ever-tightening demands for more precise process controls and higher productivity.« less

Fireman's lamp

NASA Technical Reports Server (NTRS)

Britz, W. J.; Varnedoe, W. W., Jr.

1977-01-01

Rugged lamp used by miners is adapted for firefighters by utilization of smaller, rechargeable 3-hour-life gel-cell battery. Lighter, maintenance free unit can be clipped to outer clothing for convenience. Small monitor circuit indicates need to recharge battery.

Investigations of HID Lamp Electrodes under HF Operation

NASA Astrophysics Data System (ADS)

Reinelt, Jens; Langenscheidt, Oliver; Westermeier, Michael; Mentel, Juergen; Awakowicz, Peter

2007-10-01

Low pressure lamps are operated many years at high frequencies to improve the efficiency of these lamps and drivers. For high pressure discharge lamps this operation mode has not been installed yet. Generally it can be assumed that there are changes in the electrode physics which may lead to an undesired lamp behavior if HID lamps are operated at a high frequency. To gain insights into these fundamental changes the so called Bochum Model Lamp is used. It is an easy system which allows a fundamental research on HID electrode behavior and the near electrode region without the occurrence of acoustic resonances. For the investigation phase resolved photography, pyrometry and spectrometry is used. The presented results describe changes in the electrode temperature and changes in the kind of arc attachment on the electrodes (diffuse and spot mode) depending on frequency. Also measurements of the Electrode-Sheath-Voltage (ESV), depending on frequency, are presented.

Integrity Monitoring of Mercury Discharge Lamps

NASA Technical Reports Server (NTRS)

Tjoelker, Robert L.

2010-01-01

Mercury discharge lamps are critical in many trapped ion frequency standard applications. An integrity monitoring system can be implemented using end-of-life signatures observed in operational mercury discharge lamps, making it possible to forecast imminent failure and to take action to mitigate the consequences (such as switching to a redundant system). Mercury lamps are used as a source of 194-nm ultraviolet radiation for optical pumping and state selection of mercury trapped ion frequency standards. Lamps are typically fabricated using 202Hg distilled into high-purity quartz, or other 194-nm transmitting material (e.g., sapphire). A buffer gas is also placed into the bulb, typically a noble gas such as argon, neon, or krypton. The bulbs are driven by strong RF fields oscillating at .200 MHz. The lamp output may age over time by two internal mechanisms: (1) the darkening of the bulb that attenuates light transmission and (2) the loss of mercury due to migration or chemical interactions with the bulb surface. During fabrication, excess mercury is placed into a bulb, so that the loss rate is compensated with new mercury emanating from a cool tip or adjacent reservoir. The light output is nearly constant or varies slightly at a constant rate for many months/years until the mercury source is depleted. At this point, the vapor pressure abruptly falls and the total light output and atomic clock SNR (signal-to-noise ratio) decrease. After several days to weeks, the light levels decrease to a point where the atomic clock SNR is no longer sufficient to stay in lock, or the lamp self-extinguishes. This signature has been observed in four separate end-of-life lamp failures while operating in the Deep Space Network (DSN). A simple integrator circuit can observe and document steady-state lamp behavior. When the light levels drop over a predetermined time interval by a specified amount (e.g., 20 percent), an alarm is set. For critical operational applications, such as the DSN

Optical properties of implanted Xe color centers in diamond

NASA Astrophysics Data System (ADS)

Sandstrom, Russell; Ke, Li; Martin, Aiden; Wang, Ziyu; Kianinia, Mehran; Green, Ben; Gao, Wei-bo; Aharonovich, Igor

2018-03-01

Optical properties of color centers in diamond have been the subject of intense research due to their promising applications in quantum photonics. In this work we study the optical properties of Xe related color centers implanted into nitrogen rich (type IIA) and an ultrapure, electronic grade diamond. The Xe defect has two zero phonon lines at ∼794 nm and 811 nm, which can be effectively excited using both green and red excitation, however, its emission in the nitrogen rich diamond is brighter. Near resonant excitation is performed at cryogenic temperatures and luminescence is probed under strong magnetic field. Our results are important towards the understanding of the Xe related defect and other near infrared color centers in diamond.

Light transmission and ultraviolet protection of contact lenses under artificial illumination.

PubMed

Artigas, José M; Navea, Amparo; García-Domene, M Carmen; Gené, Andrés; Artigas, Cristina

2016-04-01

To determine the spectral transmission of contact lenses (CLs), with and without an ultraviolet (UV) filter to evaluate their capacity for protection under UV radiation from artificial illumination (incandescent, fluorescent, xenon (Xe) lamps, or white LEDs (light-emitting diode)). The transmission curves of nine soft CLs were obtained by using a PerkinElmer Lambda 35 UV-vis spectrophotometer. A CIE standard was used for the emission spectra of incandescent and fluorescent lamps, and Xe lamps and white LEDs were measured by using an International Light Technologies ILT-950 spectroradiometer. Five of the nine soft CLs analysed state that they incorporate UV filters, but the other four do not specify anything in this regard. The spectral transmission of all the CLs studied is excellent in the visible region. The CLs with UV filters filter out this radiation more or less effectively. Xe lamps emit a part in the UV region. Incandescent, fluorescent and white LEDs do not emit at all in the UV. Incorporating UV filters is important when the illumination is from a Xe lamp since this light source emits in the UV region. This, however, does not occur with incandescent and fluorescent lamps or white LEDs. The CLs that do incorporate UV filters meet all the standard requirements that the U.S. FDA (Food and Drug Administration) has for UV-blocking CLs Class II (OcularScience, CooperVision and Neolens), and AcuvueMoist and HydronActifresh400 even comply with the stricter Class I. The CLs without UV filters let UVA, UVB and even some UVC through. Copyright © 2015. Published by Elsevier Ltd.

30 CFR 20.10 - Tests (class 1 and 2 lamps).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Tests (class 1 and 2 lamps). 20.10 Section 20..., AND APPROVAL OF MINING PRODUCTS ELECTRIC MINE LAMPS OTHER THAN STANDARD CAP LAMPS § 20.10 Tests (class 1 and 2 lamps). Such tests will be made as are necessary to prove the adequacy of a lamp or any of...

30 CFR 20.10 - Tests (class 1 and 2 lamps).

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Tests (class 1 and 2 lamps). 20.10 Section 20..., AND APPROVAL OF MINING PRODUCTS ELECTRIC MINE LAMPS OTHER THAN STANDARD CAP LAMPS § 20.10 Tests (class 1 and 2 lamps). Such tests will be made as are necessary to prove the adequacy of a lamp or any of...

30 CFR 20.10 - Tests (class 1 and 2 lamps).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Tests (class 1 and 2 lamps). 20.10 Section 20..., AND APPROVAL OF MINING PRODUCTS ELECTRIC MINE LAMPS OTHER THAN STANDARD CAP LAMPS § 20.10 Tests (class 1 and 2 lamps). Such tests will be made as are necessary to prove the adequacy of a lamp or any of...

Hold-up power supply for flash memory

NASA Technical Reports Server (NTRS)

Ott, William E. (Inventor)

2004-01-01

A hold-up power supply for flash memory systems is provided. The hold-up power supply provides the flash memory with the power needed to temporarily operate when a power loss exists. This allows the flash memory system to complete any erasures and writes, and thus allows it to shut down gracefully. The hold-up power supply detects when a power loss on a power supply bus is occurring and supplies the power needed for the flash memory system to temporally operate. The hold-up power supply stores power in at least one capacitor. During normal operation, power from a high voltage supply bus is used to charge the storage capacitors. When a power supply loss is detected, the power supply bus is disconnected from the flash memory system. A hold-up controller controls the power flow from the storage capacitors to the flash memory system. The hold-up controller uses feedback to assure that the proper voltage is provided from the storage capacitors to the flash memory system. This power supplied by the storage capacitors allows the flash memory system to complete any erasures and writes, and thus allows the flash memory system to shut down gracefully.

Improved xenon lamp for solar simulators: A concept

NASA Technical Reports Server (NTRS)

Schmidt, L. F.

1974-01-01

Short-arc xenon lamp proposes to produce more uniform solar output. With this lamp, both axes of sensors can be tested with same setup. Lamp includes cathode with conical tip and annular anode. Annulus is supported by angled projection to avoid interference with passage of light generated by arc.

46 CFR 92.05-10 - Lamp room construction.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Lamp room construction. 92.05-10 Section 92.05-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT General Fire Protection § 92.05-10 Lamp room construction. (a) Lamp, paint, and...

46 CFR 92.05-10 - Lamp room construction.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Lamp room construction. 92.05-10 Section 92.05-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT General Fire Protection § 92.05-10 Lamp room construction. (a) Lamp, paint, and...

46 CFR 92.05-10 - Lamp room construction.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Lamp room construction. 92.05-10 Section 92.05-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT General Fire Protection § 92.05-10 Lamp room construction. (a) Lamp, paint, and...

46 CFR 92.05-10 - Lamp room construction.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Lamp room construction. 92.05-10 Section 92.05-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT General Fire Protection § 92.05-10 Lamp room construction. (a) Lamp, paint, and...

46 CFR 92.05-10 - Lamp room construction.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Lamp room construction. 92.05-10 Section 92.05-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT General Fire Protection § 92.05-10 Lamp room construction. (a) Lamp, paint, and...

49 CFR 234.217 - Flashing light units.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Flashing light units. 234.217 Section 234.217..., Inspection, and Testing Maintenance Standards § 234.217 Flashing light units. (a) Each flashing light unit.... (b) Each flashing light unit shall be maintained to prevent dust and moisture from entering the...

49 CFR 234.217 - Flashing light units.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Flashing light units. 234.217 Section 234.217..., Inspection, and Testing Maintenance Standards § 234.217 Flashing light units. (a) Each flashing light unit.... (b) Each flashing light unit shall be maintained to prevent dust and moisture from entering the...

Lamp modulator provides signal magnitude indication

NASA Technical Reports Server (NTRS)

Zeman, J. R.

1970-01-01

Lamp modulator provides visible indication of presence and magnitude of an audio signal carrying voice or data. It can be made to reflect signal variations of up to 32 decibels. Lamp life is increased by use of a bypass resistor to prevent filament failure.

RF driven sulfur lamp having driving electrodes arranged to cool the lamp

DOEpatents

Gabor, G.; Orr, T.R.; Greene, C.M.; Crawford, D.G.; Berman, S.M.

1998-10-20

A high intensity discharge lamp without mercury is disclosed radiating a selected spectrum of which can be almost entirely in the visible range from an envelope that contains a sulfur containing substance. The lamp utilizes a signal source that generates an excitation signal that is externally coupled to the exterior surface of the envelope to excite the enclosed sulfur containing substance. Various embodiments of the lamp use electrodes adjacent the envelope to couple the excitation signal thereto with the face of the electrodes shaped to complement the shape of the exterior surface of the envelope. Two shapes discussed are spherical and cylindrical. To minimize filamentary discharges each envelope may include an elongated stem affixed to the exterior thereof whereby a rotational subsystem spins the envelope. In yet another embodiment the envelope has a Dewar configuration with two electrodes, one positioned near the external curved side surface of the body, and a second to the inner surface of the hole through the envelope. Further, the envelope may contain a backfill of a selected inert gas to assist in the excitation of lamp with that backfill at a pressure of less than 1 atmosphere, wherein the backfill pressure is directly related to the increase or decrease of peak output and inversely related to the increase and decrease of the emitted spectrum from the envelope. The emitting fill can be less than 6 mg/cc, or at least 2 mg/cc of the envelope of a sulfur containing substance. 17 figs.

46 CFR 72.03-15 - Lamp room construction.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 3 2010-10-01 2010-10-01 false Lamp room construction. 72.03-15 Section 72.03-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS CONSTRUCTION AND ARRANGEMENT General Fire Protection § 72.03-15 Lamp room construction. (a) Lamp, paint, and oil lockers and...

46 CFR 72.03-15 - Lamp room construction.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 3 2014-10-01 2014-10-01 false Lamp room construction. 72.03-15 Section 72.03-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS CONSTRUCTION AND ARRANGEMENT General Fire Protection § 72.03-15 Lamp room construction. (a) Lamp, paint, and oil lockers and...

46 CFR 72.03-15 - Lamp room construction.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 3 2013-10-01 2013-10-01 false Lamp room construction. 72.03-15 Section 72.03-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS CONSTRUCTION AND ARRANGEMENT General Fire Protection § 72.03-15 Lamp room construction. (a) Lamp, paint, and oil lockers and...

46 CFR 72.03-15 - Lamp room construction.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 3 2012-10-01 2012-10-01 false Lamp room construction. 72.03-15 Section 72.03-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS CONSTRUCTION AND ARRANGEMENT General Fire Protection § 72.03-15 Lamp room construction. (a) Lamp, paint, and oil lockers and...

46 CFR 72.03-15 - Lamp room construction.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 3 2011-10-01 2011-10-01 false Lamp room construction. 72.03-15 Section 72.03-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS CONSTRUCTION AND ARRANGEMENT General Fire Protection § 72.03-15 Lamp room construction. (a) Lamp, paint, and oil lockers and...

Atomic Oxygen Lamp Cleaning Facility Fabricated and Tested

NASA Technical Reports Server (NTRS)

Sechkar, Edward A.; Stueber, Thomas J.

1999-01-01

NASA Lewis Research Center's Atomic Oxygen Lamp Cleaning Facility was designed to produce an atomic oxygen plasma within a metal halide lamp to remove carbon-based contamination. It is believed that these contaminants contribute to the high failure rate realized during the production of these lamps. The facility is designed to evacuate a metal halide lamp and produce a radio frequency generated atomic oxygen plasma within it. Oxygen gas, with a purity of 0.9999 percent and in the pressure range of 150 to 250 mtorr, is used in the lamp for plasma generation while the lamp is being cleaned. After cleaning is complete, the lamp can be backfilled with 0.9999-percent pure nitrogen and torch sealed. The facility comprises various vacuum components connected to a radiation-shielded box that encloses the bulb during operation. Radiofrequency power is applied to the two parallel plates of a capacitor, which are on either side of the lamp. The vacuum pump used, a Leybold Trivac Type D4B, has a pumping speed of 4-m3/hr, has an ultimate pressure of <8x10-4, and is specially adapted for pure oxygen service. The electronic power supply, matching network, and controller (500-W, 13.56-MHz) used to supply the radiofrequency power were purchased from RF Power Products Inc. Initial test results revealed that this facility could remove the carbon-based contamination from within bulbs.

Photochemical methods to assay DNA photocleavage using supercoiled pUC18 DNA and LED or xenon arc lamp excitation.

PubMed

Prussin, Aaron J; Zigler, David F; Jain, Avijita; Brown, Jared R; Winkel, Brenda S J; Brewer, Karen J

2008-04-01

Methods for the study of DNA photocleavage are illustrated using a mixed-metal supramolecular complex [{(bpy)(2)Ru(dpp)}(2)RhCl(2)]Cl(5). The methods use supercoiled pUC18 plasmid as a DNA probe and either filtered light from a xenon arc lamp source or monochromatic light from a newly designed, high-intensity light-emitting diode (LED) array. Detailed methods for performing the photochemical experiments and analysis of the DNA photoproduct are delineated. Detailed methods are also given for building an LED array to be used for DNA photolysis experiments. The Xe arc source has a broad spectral range and high light flux. The LEDs have a high-intensity, nearly monochromatic output. Arrays of LEDs have the advantage of allowing tunable, accurate output to multiple samples for high-throughput photochemistry experiments at relatively low cost.

Measuring hot flash phenomenonology using ambulatory prospective digital diaries

PubMed Central

Fisher, William I.; Thurston, Rebecca C.

2016-01-01

Objective This study provides the description, protocol, and results from a novel prospective ambulatory digital hot flash phenomenon diary. Methods This study included 152 midlife women with daily hot flashes who completed an ambulatory electronic hot flash diary continuously for the waking hours of 3 consecutive days. In this diary, women recorded their hot flashes and accompanying characteristics and associations as the hot flashes occurred. Results Self-reported hot flash severity on the digital diaries indicated that the majority of hot flashes were rated as mild (41.3%) or moderate (43.7%). Severe (13.1%) and very severe (1.8%) hot flashes were less common. Hot flash bother ratings were rated as mild (43%), or moderate (33.5%), with fewer hot flashes reported bothersome (17.5%) or very bothersome (6%). The majority of hot flashes were reported as occurring on the on the face (78.9%), neck (74.7%), and chest (61.3%). Prickly skin was reported concurrently with 32% of hot flashes, 7% with anxiety and 5% with nausea. A novel finding, 38% of hot flashes were accompanied by a premonitory aura. Conclusion A prospective electronic digital hot flash diary allows for a more precise quantitation of hot flashes while overcoming many of the limitations of commonly employed retrospective questionnaires and paper diaries. Unique insights into the phenomenology, loci and associated characteristics of hot flashes were obtained using this device. The digital hot flash phenomenology diary is recommended for future ambulatory studies of hot flashes as a prospective measure of the hot flash experience. PMID:27404030

Measuring hot flash phenomenonology using ambulatory prospective digital diaries.

PubMed

Fisher, William I; Thurston, Rebecca C

2016-11-01

This study provides the description, protocol, and results from a novel prospective ambulatory digital hot flash phenomenon diary. This study included 152 midlife women with daily hot flashes who completed an ambulatory electronic hot flash diary continuously for the waking hours of three consecutive days. In this diary, women recorded their hot flashes and accompanying characteristics and associations as the hot flashes occurred. Self-reported hot flash severity on the digital diaries indicated that the majority of hot flashes were rated as mild (41.3%) or moderate (43.7%). Severe (13.1%) and very severe (1.8%) hot flashes were less common. Hot flash bother ratings were rated as mild (43%), or moderate (33.5%), with fewer hot flashes reported bothersome (17.5%) or very bothersome (6%). The majority of hot flashes were reported as occurring on the face (78.9%), neck (74.7%), and chest (61.3%). Of all reported hot flashes, 32% occurred concurrently with prickly skin, 7% with anxiety, and 5% with nausea. A novel finding from the study was that 38% of hot flashes were accompanied by a premonitory aura. A prospective electronic digital hot flash diary allows for a more precise quantitation of hot flashes while overcoming many of the limitations of commonly used retrospective questionnaires and paper diaries. Unique insights into the phenomenology, loci, and associated characteristics of hot flashes were obtained using this device. The digital hot flash phenomenology diary is recommended for future ambulatory studies of hot flashes as a prospective measure of the hot flash experience.

Fluorescent lamp unit with magnetic field generating means

DOEpatents

Grossman, Mark W.; George, William A.

1989-01-01

A fluorescent lamp unit having a magnetic field generating means for improving the performance of the fluorescent lamp is disclosed. In a preferred embodiment the fluorescent lamp comprises four longitudinally extending leg portions disposed in substantially quadrangular columnar array and joined by three generally U-shaped portions disposed in different planes. In another embodiment of the invention the magnetic field generating means comprises a plurality of permanent magnets secured together to form a single columnar structure disposed within a centrally located region defined by the shape of lamp envelope.

Fluorescent lamp unit with magnetic field generating means

DOEpatents

Grossman, M.W.; George, W.A.

1989-08-08

A fluorescent lamp unit having a magnetic field generating means for improving the performance of the fluorescent lamp is disclosed. In a preferred embodiment the fluorescent lamp comprises four longitudinally extending leg portions disposed in substantially quadrangular columnar array and joined by three generally U-shaped portions disposed in different planes. In another embodiment of the invention the magnetic field generating means comprises a plurality of permanent magnets secured together to form a single columnar structure disposed within a centrally located region defined by the shape of lamp envelope. 4 figs.

Nuclear Structure of 124Xe Studied with β+/EC-Decay

NASA Astrophysics Data System (ADS)

Radich, A. J.; Garrett, P. E.; Allmond, J. M.; Andreoiu, C.; Ball, G. C.; Bianco, L.; Bildstein, V.; Chagnon-Lessard, S.; Cross, D. S.; Diaz Varela, A.; Dunlop, R.; Finlay, P.; Garnsworthy, A. B.; Hackman, G.; Hadinia, B.; Jigmeddorj, B.; Laffoley, A. T.; Leach, K. G.; Michetti-Wilson, J.; Orce, J. N.; Rajabali, M. M.; Rand, E.; Starosta, K.; Sumithrarachchi, C. S.; Svensson, C. E.; Triambak, S.; Wang, Z. M.; Wood, J. L.; Wong, J.; Williams, S. J.; Yates, S. W.

The nuclear structure of 124Xe was investigated using γ-ray spectroscopy following the β+/EC-decay of 124Cs. A very high-statistics data set was collected and γγ coincidence data was analyzed, greatly adding to the 124Xe level scheme. A new decay branch from the high-spin isomer of 124Cs was observed as well as weak E2 transitions into excited 0+ states in 124Xe. B(E2) transition strengths of such low-spin transitions are very important in determining collective properties, which are currently poorly characterized in the region of neutron-deficient xenon isotopes.

XeCl avalanche discharge laser employing Ar as a diluent

DOEpatents

Sze, R.C.

1979-10-10

A XeCl avalanche discharge exciplex laser which uses a gaseous lasing starting mixture of: 0.2 to 0.4% chlorine donor/2.5% to 10% Xe/97.3% to 89.6% Ar) is provided. The chlorine donor normally comprises HCl but can also comprise CCl/sub 4/ BCl/sub 3/. Use of Ar as a diluent gas reduces operating pressures over other rare gas halide lasers to near atmospheric pressure, increases output lasing power of the XeCl avalanche discharge laser by 30% to exceed KrF avalanche discharge lasing outputs, and is less expensive to operate.

Highly Efficient Small Form Factor LED Retrofit Lamp

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steven Allen; Fred Palmer; Ming Li

2011-09-11

This report summarizes work to develop a high efficiency LED-based MR16 lamp downlight at OSRAM SYLVANIA under US Department of Energy contract DE-EE0000611. A new multichip LED package, electronic driver, and reflector optic were developed for these lamps. At steady-state, the lamp luminous flux was 409 lumens (lm), luminous efficacy of 87 lumens per watt (LPW), CRI (Ra) of 87, and R9 of 85 at a correlated color temperature (CCT) of 3285K. The LED alone achieved 120 lumens per watt efficacy and 600 lumen flux output at 25 C. The driver had 90% electrical conversion efficiency while maintaining excellent powermore » quality with power factor >0.90 at a power of only 5 watts. Compared to similar existing MR16 lamps using LED sources, these lamps had much higher efficacy and color quality. The objective of this work was to demonstrate a LED-based MR16 retrofit lamp for replacement of 35W halogen MR16 lamps having (1) luminous flux of 500 lumens, (2) luminous efficacy of 100 lumens per watt, (3) beam angle less than 40{sup o} and center beam candlepower of at least 1000 candelas, and (4) excellent color quality.« less

High resolution, low h{nu} photoelectron spectroscopy with the use of a microwave excited rare gas lamp and ionic crystal filters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suga, S.; Sekiyama, A.; Funabashi, G.

2010-10-15

The need for not only bulk sensitive but also extremely high resolution photoelectron spectroscopy for studying detailed electronic structures of strongly correlated electron systems is growing rapidly. Moreover, easy access to such a capability in one's own laboratory is desirable. Demonstrated here is the performance of a microwave excited rare gas (Xe, Kr, and Ar) lamp combined with ionic crystal filters (sapphire, CaF{sub 2}, and LiF), which can supply three strong lines near the photon energy of hnyu h{nu}=8.4, 10.0, and 11.6 eV, with the h{nu} resolution of better than 600 {mu}eV for photoelectron spectroscopy. Its performance is demonstrated onmore » some materials by means of both angle-integrated and angle-resolved measurements.« less

APPI-MS: Effects of mobile phases and VUV lamps on the detection of PAH compounds

PubMed Central

Short, Luke Chandler; Cai, Sheng-Suan; Syage, Jack A.

2009-01-01

The technique of atmospheric pressure photoionization (APPI) has several advantages over electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI), including efficient ionization of non-polar or low charge affinity compounds, reduced susceptibility to ion suppression, high sensitivity, and large linear dynamic range. These benefits are greatest at low flow rates (i.e., ≤100 μL/min), while at a higher flow, photon absorption and ion-molecule reactions become significant. Under certain circumstances, APPI signal and S/N have been observed to excel at higher flow, which may be due to a non-photoionzation mechanism. To better understand APPI at higher flow rates, we have selected three lamps (Xe, Kr and Ar) and four mobile phases typical for reverse-phase, high-pressure liquid chromatography: acetonitrile, methanol, (1:1) acetonitrile:water and (1:1) methanol:water. As test compounds, three polyaromatic hydrocarbons are studied: benzo[a]pyrene, indeno[1,2,3-c,d]pyrene and benz[a]anthracene. We find that solvent photoabsorption cross-section is not the only parameter in explaining relative signal intensity, but that solvent photo-ion chemistry can also play a significant role. Three conclusions from this investigation are: (i) Methanol photoionization leads to protonated methanol clusters that can result in chemical ionization of analyte molecule; (ii) Use of the Ar lamp often results in greater signal and S/N; (iii) Acetonitrile photoionization is less efficient and resulting clusters are too strongly bound to efficiently chemically ionize the analyte, so that analyte ion formation is dominated by direct photoionization. PMID:17188507

APPI-MS: effects of mobile phases and VUV lamps on the detection of PAH compounds.

PubMed

Short, Luke Chandler; Cai, Sheng-Suan; Syage, Jack A

2007-04-01

The technique of atmospheric pressure photoionization (APPI) has several advantages over electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI), including efficient ionization of nonpolar or low charge affinity compounds, reduced susceptibility to ion suppression, high sensitivity, and large linear dynamic range. These benefits are greatest at low flow rates (i.e., lamps (Xe, Kr, and Ar) and four mobile phases typical for reverse-phase, high-pressure liquid chromatography: acetonitrile, methanol, (1:1) acetonitrile:water and (1:1) methanol:water. As test compounds, three polyaromatic hydrocarbons are studied: benzo[a]pyrene, indeno[1,2,3-c, d]pyrene and benz[a]anthracene. We find that solvent photoabsorption cross-section is not the only parameter in explaining relative signal intensity, but that solvent photo-ion chemistry can also play a significant role. Three conclusions from this investigation are: (1) methanol photoionization leads to protonated methanol clusters that can result in chemical ionization of analyte molecule; (2) use of the Ar lamp often results in greater signal and S/N; (3) acetonitrile photoionization is less efficient and resulting clusters are too strongly bound to chemically ionize the analyte efficiently, so that analyte ion formation is dominated by direct photoionization.

[Remote Slit Lamp Microscope Consultation System Based on Web].

PubMed

Chen, Junfa; Zhuo, Yong; Liu, Zuguo; Chen, Yanping

2015-11-01

To realize the remote operation of the slit lamp microscope for department of ophthalmology consultation, and visual display the real-time status of remote slit lamp microscope, a remote slit lamp microscope consultation system based on B/S structure is designed and implemented. Through framing the slit lamp microscope on the website system, the realtime acquisition and transmission of remote control and image data is realized. The three dimensional model of the slit lamp microscope is established and rendered on the web by using WebGL technology. The practical application results can well show the real-time interactive of the remote consultation system.

Theoretical Calculations of XeF Ground State Kinetics.

DTIC Science & Technology

1988-03-01

potential parameters for XeF are taken from Tellinghuisen et al. 3 The values of the Lennard - Jones parameters for HeF...parameters for the Morse potential and the Lennard - Jones potentials are listed in Table 1. These parameters for the Lennard - Jones potentials produce the...relaxation and dissociation. 13 ~ o Table 1. Potential Parameters. Morse Function (XeF)3 De = 3.35 kcal/mol ae=1.726 a.u.-1 re =4.367 a.u. Lennard Jones

LED solution for E14 candle lamp

NASA Astrophysics Data System (ADS)

Li, Yun; Liu, Ye; Boonekamp, Erik P.; Shi, Lei; Mei, Yi; Jiang, Tan; Guo, Qing; Wu, Huarong

2009-08-01

On a short to medium term, energy efficient retrofit LED products can offer an attractive solution for traditional lamps replacement in existing fixtures. To comply with user expectations, LED retrofit lamps should not only have the same mechanical interface to fit (socket and shape), but also have the similar light effect as the lamps they replace. The decorative lighting segment shows the best conditions to meet these requirements on short term. In 2008, Philips Lighting Shanghai started with the development of an LED candle lamp for the replacement of a 15W Candle shape (B35 E14) incandescent bulb, which is used in e.g. chandeliers. In this decorative application the main objective is not to generate as much light as possible, but the application requires the lamp to have a comparable look and, primarily, the same light effect as the incandescent candle lamp. This effect can be described as sparkling light, and it has to be directed sufficiently downwards (i.e., in the direction of the base of the lamp). These requirements leave very limited room for optics, electronics, mechanics and thermal design to play with in the small outline of this lamp. The main voltage AC LED concept is chosen to save the space for driver electronics. However the size of the AC LED is relatively big, which makes the optical design challenging. Several optical solutions to achieve the required light effect, to improve the optical efficiency, and to simplify the system are discussed. A novel prismatic lens has been developed which is capable of transforming the Lambertian light emission from typical high power LEDs into a butter-fly intensity distribution with the desired sparkling light effect. Thanks to this lens no reflecting chamber is needed, which improves the optical efficiency up to 70%, while maintaining the compact feature of the original optics. Together with advanced driver solution and thermal solution, the resulting LED candle lamp operates at 230V, consumes 1.8W, and

Optical properties of implanted Xe color centers in diamond

DOE PAGES

Sandstrom, Russell; Ke, Li; Martin, Aiden; ...

2017-12-20

Optical properties of color centers in diamond have been the subject of intense research due to their promising applications in quantum photonics. Here in this work we study the optical properties of Xe related color centers implanted into nitrogen rich (type IIA) and an ultrapure, electronic grade diamond. The Xe defect has two zero phonon lines at 794 nm and 811 nm, which can be effectively excited using both green and red excitation, however, its emission in the nitrogen rich diamond is brighter. Near resonant excitation is performed at cryogenic temperatures and luminescence is probed under strong magnetic field. Finally,more » our results are important towards the understanding of the Xe related defect and other near infrared color centers in diamond.« less

Optical properties of implanted Xe color centers in diamond

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sandstrom, Russell; Ke, Li; Martin, Aiden

Optical properties of color centers in diamond have been the subject of intense research due to their promising applications in quantum photonics. Here in this work we study the optical properties of Xe related color centers implanted into nitrogen rich (type IIA) and an ultrapure, electronic grade diamond. The Xe defect has two zero phonon lines at 794 nm and 811 nm, which can be effectively excited using both green and red excitation, however, its emission in the nitrogen rich diamond is brighter. Near resonant excitation is performed at cryogenic temperatures and luminescence is probed under strong magnetic field. Finally,more » our results are important towards the understanding of the Xe related defect and other near infrared color centers in diamond.« less

Slit-lamp photography and videography with high magnifications

PubMed Central

Yuan, Jin; Jiang, Hong; Mao, Xinjie; Ke, Bilian; Yan, Wentao; Liu, Che; Cintrón-Colón, Hector R; Perez, Victor L; Wang, Jianhua

2015-01-01

Purpose To demonstrate the use of the slit-lamp photography and videography with extremely high magnifications for visualizing structures of the anterior segment of the eye. Methods A Canon 60D digital camera with Movie Crop Function was adapted into a Nikon FS-2 slit-lamp to capture still images and video clips of the structures of the anterior segment of the eye. Images obtained using the slit-lamp were tested for spatial resolution. The cornea of human eyes was imaged with the slit-lamp and the structures were compared with the pictures captured using the ultra-high resolution optical coherence tomography (UHR-OCT). The central thickness of the corneal epithelium and total cornea was obtained using the slit-lamp and the results were compared with the thickness obtained using UHR-OCT. Results High-quality ocular images and higher spatial resolutions were obtained by using the slit-lamp with extremely high magnifications and Movie Crop Function, rather than the traditional slit-lamp. The structures and characteristics of the cornea, such as the normal epithelium, abnormal epithelium of corneal intraepithelial neoplasia, LASIK interface, and contact lenses, were clearly visualized using this device. These features were confirmed by comparing the obtained images with those acquired using UHR-OCT. Moreover, the tear film debris on the ocular surface and the corneal nerve in the anterior corneal stroma were also visualized. The thicknesses of the corneal epithelium and total cornea were similar to that measured using UHR-OCT (P < 0.05). Conclusions We demonstrated that the slit-lamp photography and videography with extremely high magnifications allows better visualization of the anterior segment structures of the eye, especially of the epithelium, when compared with the traditional slit-lamp. PMID:26020484

21 CFR 878.4635 - Ultraviolet lamp for tanning.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ultraviolet lamp for tanning. 878.4635 Section 878... tanning. (a) Identification. An ultraviolet lamp for tanning is a device that is a lamp (including a fixture) intended to provide ultraviolet radiation to tan the skin. See § 1040.20 of this chapter. (b...

21 CFR 890.5500 - Infrared lamp.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Infrared lamp. 890.5500 Section 890.5500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp. (a...

21 CFR 890.5500 - Infrared lamp.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Infrared lamp. 890.5500 Section 890.5500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp. (a...

21 CFR 890.5500 - Infrared lamp.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Infrared lamp. 890.5500 Section 890.5500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp. (a...

21 CFR 890.5500 - Infrared lamp.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Infrared lamp. 890.5500 Section 890.5500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp. (a...

21 CFR 890.5500 - Infrared lamp.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Infrared lamp. 890.5500 Section 890.5500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5500 Infrared lamp. (a...

An intense radiation in mid-infrared of Xe

NASA Astrophysics Data System (ADS)

He, Shan; Liu, Dong; Guo, Jingwei; Sang, Fengting

2017-01-01

Recently, the optically pumped rare gas lasers have been attracted extensive attention. Rare gas laser systems with Ne (2p53p), Ar (3p54p), and Kr (4p55p) atoms have been investigated. However, there are sparse studies based on Xe. In this work, new phenomena, intensive mid-infrared amplified spontaneous emissions (ASEs), are found after two-photon excitation of Xe from the ground state to the 6p[1/2]0 state. Simultaneously, substantial 6p[1/2]1 atoms are populated. The thresholds of ASE peak 1 and the generation of 6p[1/2]1 atoms are both about 1.5 mJ. It indicates that there should exist the relationship between these two phenomena. The ASE signals show broadband spectra. Therefore, it must be yielded by the superposition of Xe2* excimer transitions. The mid-infrared ASEs lead to excimers correlating to the 6s'[1/2]1 enormously generated. Then these excimers dissociate to produce substantial 6p[1/2]1 atoms. Under some circumstance, the ratio of the 6p[1/2]1 to 6p[1/2]0 atoms reaches about 80%. It indicates that the 6p[1/2]0 atoms strongly tend to decay through the emissions between the excimer states. Using these emissions, continuous-tunable mid-infrared laser with metastable Xe can be promisingly produced.

High frequency inductive lamp and power oscillator

DOEpatents

MacLennan, Donald A.; Turner, Brian P.; Dolan, James T.; Kirkpatrick, Douglas A.; Leng, Yongzhang

2000-01-01

A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and/or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to match the driving frequency of the oscillator to a plurality of tuning states of the lamp.

Spontaneous and induced emission of XeCl* excimer molecules under pumping of Xe - CCl4 and Ar - Xe - CCl4 gas mixtures with a low CCl4 content by fast electrons and uranium fission fragments

NASA Astrophysics Data System (ADS)

Mis'kevich, A. I.; Guo, J.; Dyuzhov, Yu A.

2013-11-01

The spontaneous and induced emission of XeCl* excimer molecules upon excitation of Xe - CCl4 and Ar - Xe - CCl4 gas mixtures with a low CCl4 content by high-energy charged particles [a pulsed high-energy electron beam and products of neutron nuclear reaction 235U(n, f)] has been experimentally studied. The electron energy was 150 keV, and the pump current pulse duration and amplitude were 5 ns and 5 A, respectively. The energy of fission fragments did not exceed 100 MeV, the duration of the neutron pump pulse was 200 μs, and the specific power contribution to the gas was about 300 W cm-3. Electron beam pumping in a cell 4 cm long with a cavity having an output mirror transmittance of 2.7% gives rise to lasing on the B → X transition in the XeCl* molecule (λ = 308 nm) with a gain α = 0.0085 cm-1 and fluorescence efficiency η ≈ 10%. Pumping by fission fragments in a 250-cm-long cell with a cavity formed by a highly reflecting mirror and a quartz window implements amplified spontaneous emission (ASE) with an output power of 40 - 50 kW sr-1 and a base ASE pulse duration of ~200 ms.

Theoretical study of the NMR chemical shift of Xe in supercritical condition.

PubMed

Lacerda, Evanildo G; Sauer, Stephan P A; Mikkelsen, Kurt V; Coutinho, Kaline; Canuto, Sylvio

2018-02-20

In this work we investigate the level of theory necessary for reproducing the non-linear variation of the 129 Xe nuclear magnetic resonance (NMR) chemical shift with the density of Xe in supercritical conditions. In detail we study how the 129 Xe chemical shift depends under supercritical conditions on electron correlation, relativistic and many-body effects. The latter are included using a sequential-QM/MM methodology, in which a classical MD simulation is performed first and the chemical shift is then obtained as an average of quantum calculations of 250 MD snapshots conformations carried out for Xe n clusters (n = 2 - 8 depending on the density). The analysis of the relativistic effects is made at the level of 4-component Hartree-Fock calculations (4c-HF) and electron correlation effects are considered using second order Møller-Plesset perturbation theory (MP2). To simplify the calculations of the relativistic and electron correlation effects we adopted an additive scheme, where the calculations on the Xe n clusters are carried out at the non-relativistic Hartree-Fock (HF) level, while electron correlation and relativistic corrections are added for all the pairs of Xe atoms in the clusters. Using this approach we obtain very good agreement with the experimental data, showing that the chemical shift of 129 Xe in supercritical conditions is very well described by cluster calculations at the HF level, with small contributions from relativistic and electron correlation effects.

Hyperpolarized 129Xe MRI: A Viable Functional Lung Imaging Modality?

PubMed Central

Patz, Samuel; Hersman, F. William; Muradian, Iga; Hrovat, Mirko I.; Ruset, Iulian C.; Ketel, Stephen; Jacobson, Francine; Topulos, George P.; Hatabu, Hiroto; Butler, James P.

2008-01-01

The majority of researchers investigating hyperpolarized gas MRI as a candidate functional lung imaging modality have used 3He as their imaging agent of choice rather than 129Xe. This preference has been predominantly due to, 3He providing stronger signals due to higher levels of polarization and higher gyromagnetic ratio, as well as its being easily available to more researchers due to availability of polarizers (USA) or ease of gas transport (Europe). Most researchers agree, however, that hyperpolarized 129Xe will ultimately emerge as the imaging agent of choice due to its unlimited supply in nature and its falling cost. Our recent polarizer technology delivers vast improvements in hyperpolarized 129Xe output. Using this polarizer, we have demonstrated the unique property of xenon to measure alveolar surface area noninvasively. In this article, we describe our human protocols and their safety, and our results for the measurement of the partial pressure of pulmonary oxygen (pO2) by observation of 129Xe signal decay. We note that the measurement of pO2 by observation of 129Xe signal decay is more complex than that for 3He because of an additional signal loss mechanism due to interphase diffusion of 129Xe from alveolar gas spaces to septal tissue. This results in measurements of an equivalent pO2 that accounts for both traditional T1 decay from pO2 and that from interphase diffusion. We also provide an update on new technological advancements that form the foundation for an improved compact design polarizer as well as improvements that provide another order-of-magnitude scale-up in xenon polarizer output. PMID:17890035

21 CFR 878.4580 - Surgical lamp.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Surgical lamp. 878.4580 Section 878.4580 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4580 Surgical lamp. (a) Identification. A...

21 CFR 878.4580 - Surgical lamp.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Surgical lamp. 878.4580 Section 878.4580 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4580 Surgical lamp. (a) Identification. A...

21 CFR 878.4580 - Surgical lamp.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Surgical lamp. 878.4580 Section 878.4580 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4580 Surgical lamp. (a) Identification. A...

21 CFR 878.4580 - Surgical lamp.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Surgical lamp. 878.4580 Section 878.4580 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4580 Surgical lamp. (a) Identification. A...

21 CFR 878.4580 - Surgical lamp.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Surgical lamp. 878.4580 Section 878.4580 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4580 Surgical lamp. (a) Identification. A...

Critical phenomena at a first-order phase transition in a lattice of glow lamps: Experimental findings and analogy to neural activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Minati, Ludovico, E-mail: lminati@ieee.org, E-mail: ludovico.minati@unitn.it, E-mail: ludovico.minati@ifj.edu; Complex Systems Theory Department, Institute of Nuclear Physics, Polish Academy of Sciences, Kraków; Candia, Antonio de

2016-07-15

Networks of non-linear electronic oscillators have shown potential as physical models of neural dynamics. However, two properties of brain activity, namely, criticality and metastability, remain under-investigated with this approach. Here, we present a simple circuit that exhibits both phenomena. The apparatus consists of a two-dimensional square lattice of capacitively coupled glow (neon) lamps. The dynamics of lamp breakdown (flash) events are controlled by a DC voltage globally connected to all nodes via fixed resistors. Depending on this parameter, two phases having distinct event rate and degree of spatiotemporal order are observed. The transition between them is hysteretic, thus a first-ordermore » one, and it is possible to enter a metastability region, wherein, approaching a spinodal point, critical phenomena emerge. Avalanches of events occur according to power-law distributions having exponents ≈3/2 for size and ≈2 for duration, and fractal structure is evident as power-law scaling of the Fano factor. These critical exponents overlap observations in biological neural networks; hence, this circuit may have value as building block to realize corresponding physical models.« less

Direct current ballast circuit for metal halide lamp

NASA Technical Reports Server (NTRS)

Lutus, P. (Inventor)

1981-01-01

A direct current ballast circuit for a two electrode metal halide lamp is described. Said direct current ballast circuit includes a low voltage DC input and a high frequency power amplifier and power transformer for developing a high voltage output. The output voltage is rectified by diodes and filtered by inductor and capacitor to provide a regulated DC output through commutating diodes to one terminal of the lamp at the output terminal. A feedback path from the output of the filter capacitor through the bias resistor to power the high frequency circuit which includes the power amplifier and the power transformer for sustaining circuit operations during low voltage transients on the input DC supply is described. A current sensor connected to the output of the lamp through terminal for stabilizing lamp current following breakdown of the lamp is described.

Comparative studies on dimming capabilities of retrofit LED lamps

NASA Astrophysics Data System (ADS)

Ionescu, Ciprian; Vasile, Alexandru; Codreanu, Norocel; Negroiu, Rodica

2016-12-01

These days many variants for lighting systems are available on the market, and new solutions are about to emerge. Most of the new lamps are offered in form to be retrofitted to existing sockets and luminaires. In this paper, are presented some systematically investigations on different lamps as LEDs, Compact Fluorescent Lamps (CFLs), tungsten, and new available Cold Cathode Fluorescent Lamps (CCFLs), regarding the light level, dimming performances and also the resulting flicker and power distortion performances. The light level was expressed by the illuminance level, measured for all lamps in the same conditions, at the same distance and on the same surface represented by the photometer probe.

Lamp system for uniform semiconductor wafer heating

DOEpatents

Zapata, Luis E.; Hackel, Lloyd

2001-01-01

A lamp system with a very soft high-intensity output is provided over a large area by water cooling a long-arc lamp inside a diffuse reflector of polytetrafluorethylene (PTFE) and titanium dioxide (TiO.sub.2) white pigment. The water is kept clean and pure by a one micron particulate filter and an activated charcoal/ultraviolet irradiation system that circulates and de-ionizes and biologically sterilizes the coolant water at all times, even when the long-arc lamp is off.

Electronic Flash In Data Acquisition

NASA Astrophysics Data System (ADS)

Miller, C. E.

1982-02-01

Photographic acquisition of data often may be simplified, or the data quality improved upon by employing electronic flash sources with traditional equipment or techniques. The relatively short flash duration compared to movie camera shutters, or to the long integration time of video camera provides improved spatial resolution through blur reduction, particularly important as image movement becomes a significant fraction of film format dimension. Greater accuracy typically is achieved in velocity and acceleration determinations by using a stroboscopic light source rather than a movie camera frame-rate control as a time standard. Electrical efficiency often is an important advantage of electronic flash sources since almost any necessary light level for exposure may be produced, yet the source typically is "off" most of the time. Various synchronization techniques greatly expand the precise control of exposure. Biomechanical and sports equipment studies may involve velocities up to 200 feet-per-second, and often will have associated very rapid actions of interest. The need for brief exposures increases H.s one "ZOOMS in on the action." In golf, for example, the swing may be examined using 100 microsecond (Us) flashes at rates of 60 or 120 flashes-per-second (FPS). Accurate determination of linear and rotational velocity of the ball requires 10 Us flashes at 500-1,000 FPS, while sub-Us flashes at 20,000-50,000 FPS are required to resolve the interaction of the ball and the club, head. Some seldom. used techniques involving streak photography are described, with enhanced results obtained by combining strobe with the usual continuous light source. The combination of strobe and a fast electro-mechanical shutter is considered for Us photography under daylight conditions.

Magnetic dipole strength in 128Xe and 134Xe in the spin-flip resonance region

NASA Astrophysics Data System (ADS)

Massarczyk, R.; Rusev, G.; Schwengner, R.; Dönau, F.; Bhatia, C.; Gooden, M. Â. E.; Kelley, J. Â. H.; Tonchev, A. Â. P.; Tornow, W.

2014-11-01

The magnetic dipole strength in the energy region of the spin-flip resonance is investigated in 128Xe and 134Xe using quasimonoenergetic and linearly polarized γ -ray beams at the High-Intensity γ -Ray Source facility in Durham, North Carolina, USA. Absorption cross sections were deduced for the magnetic and electric and dipole strength distributions separately for various intervals of excitation energy, including the strength of states in the unresolved quasicontinuum. The magnetic dipole strength distributions show structures resembling a resonance in the spin-flip region around an excitation energy of 8 MeV. The electric dipole strength distributions obtained from the present experiments are in agreement with the ones deduced from an earlier experiment using broad-band bremsstrahlung instead of a quasimonoenergetic beam. The experimental magnetic and electric dipole strength distributions are compared with phenomenological approximations and with predictions of a quasiparticle random phase approximation in a deformed basis.

49 CFR 392.33 - Obscured lamps or reflective devices/material.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 5 2013-10-01 2013-10-01 false Obscured lamps or reflective devices/material. 392... REGULATIONS DRIVING OF COMMERCIAL MOTOR VEHICLES Use of Lighted Lamps and Reflectors § 392.33 Obscured lamps or reflective devices/material. (a) No commercial motor vehicle shall be driven when any of the lamps...

49 CFR 392.33 - Obscured lamps or reflective devices/material.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 5 2012-10-01 2012-10-01 false Obscured lamps or reflective devices/material. 392... REGULATIONS DRIVING OF COMMERCIAL MOTOR VEHICLES Use of Lighted Lamps and Reflectors § 392.33 Obscured lamps or reflective devices/material. (a) No commercial motor vehicle shall be driven when any of the lamps...

49 CFR 392.33 - Obscured lamps or reflective devices/material.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 5 2014-10-01 2014-10-01 false Obscured lamps or reflective devices/material. 392... REGULATIONS DRIVING OF COMMERCIAL MOTOR VEHICLES Use of Lighted Lamps and Reflectors § 392.33 Obscured lamps or reflective devices/material. (a) No commercial motor vehicle shall be driven when any of the lamps...

49 CFR 392.33 - Obscured lamps or reflective devices/material.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 5 2011-10-01 2011-10-01 false Obscured lamps or reflective devices/material. 392... REGULATIONS DRIVING OF COMMERCIAL MOTOR VEHICLES Use of Lighted Lamps and Reflectors § 392.33 Obscured lamps or reflective devices/material. (a) No commercial motor vehicle shall be driven when any of the lamps...

Noble gas bond and the behaviour of XeO3 under pressure.

PubMed

Hou, Chunju; Wang, Xianlong; Botana, Jorge; Miao, Maosheng

2017-10-18

Over the past few decades, the concept of hydrogen bonds, in which hydrogen is electrophilic, has been extended to halogen bonds, chalcogen bonds and pnicogen bonds. Herein, we show that such a non-covalent bonding also exists in noble gas compounds. Using first principles calculations, we illustrate the OXe-O bond in molecular crystal XeO 3 and its effect on the behavior of this compound under pressure. Our calculations show that the covalent Xe-O bond lengths were elongated with increasing pressure and correspondingly the Xe-O stretching vibration frequencies were red shifted, which is similar to the change of H-bonds under pressure. The OXe-O bond and related hopping of O between neighboring Xe sites also correspond to the structural changes in the XeO 3 compounds at about 2 GPa. Our study extends the concept of hydrogen bonding to include all p-block elements and show a new bonding type for Noble gas elements in which it acts as an electrophilic species.

Neutron-induced Backgrounds in 134Xe for Large-Scale Neutrinoless Double-Beta Decay Experiments

NASA Astrophysics Data System (ADS)

Moriguchi, Nina; Kidd, Mary; Tornow, Werner

2016-09-01

136Xe is used in large neutrinoless double-beta (0 νββ) decay experiments, such as KamLAND- Zen and EXO 200. Though highly purified, 136Xe still contains a significant amount of 134Xe. Recently, a new nuclear energy level was found in 134Xe. If 134Xe decays from this proposed excited state, it will emit a 2485.7 keV gamma ray. Because this energy lies near the region of interest of 136Xe νββ decay experiments (Q value 2457.8 keV), it could make a significant contribution to the background. A purified gaseous sample of 134Xe will be irradiated with neutrons of an incident energy of 4.0 MeV at Triangle Universities Nuclear Laboratory and monitored with high-purity germanium detectors. The spectra obtained from these detectors will be analyzed for the presence of the 2581 keV gamma ray. We will report on the status of this experiment. Future plans include expanding this measurement to higher initial neutron energies. Tennesse Tech University CISE Grant program.

Kr/Xe Separation over a Chabazite Zeolite Membrane

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feng, Xuhui; Zong, Zhaowang; Elsaidi, Sameh K.

2016-08-10

Cryogenic distillation, the current conventional technology to separate Krypton and Xenon from air, and from nuclear reprocessing technologies, is an energy-intensive and expensive process. Membrane technology could potentially make this challenging industrial separation less energy intensive and economically viable. We demonstrate that chabazite zeolite SAPO-34 membranes effectively separated Kr/Xe gas mixtures at industrially relevant compositions. Control over membrane thickness and average crystal size led to industrial range permeances and high separation selectivities. Specifically, SAPO-34 membranes can separate Kr/Xe mixtures with Kr permeances as high as 361.4 GPU and separation selectivities of 34.8 for molar compositions close to typical concentrations ofmore » these two gases in air. In addition, SAPO-34 membranes separated Kr/Xe mixtures with Kr permeances as high as 525.7 GPU and separation selectivities up to 45.1 for molar compositions as might be encountered in nuclear reprocessing technologies. Molecular sieving and differences in diffusivities were identified as the dominant separation mechanisms.« less

30 CFR 20.10 - Tests (class 1 and 2 lamps).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Tests (class 1 and 2 lamps). 20.10 Section 20... 1 and 2 lamps). Such tests will be made as are necessary to prove the adequacy of a lamp or any of... (storage-battery lamps of class 1). (e) Temperature tests. ...

Circular, explosion-proof lamp provides uniform illumination

NASA Technical Reports Server (NTRS)

1966-01-01

Circular explosion-proof fluorescent lamp is fitted around a TV camera lens to provide shadowless illumination with a low radiant heat flux. The lamp is mounted in a transparent acrylic housing sealed with clear silicone rubber.

The Effects of Lamp Spectral Distribution on Sky Glow over Observatories

DTIC Science & Technology

2015-01-01

overhead sky glow as a function of distance up to 300 km, from a variety of lamp types, including common gas discharge lamps and several types of LED...distance up to 300 km, from a variety of lamp types, in- cluding common gas discharge lamps and several types of LED lamps . We conclude for both...MAR 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE The Effects of Lamp Spectral Distribution on Sky Glow

An ion quencher operated lamp for multiplexed fluorescent bioassays.

PubMed

Qing, Taiping; Sun, Huanhuan; He, Xiaoxiao; Huang, Xiaoqin; He, Dinggeng; Bu, Hongchang; Qiao, Zhenzhen; Wang, Kemin

2018-02-01

A novel and adjustable lamp based on competitive interaction among dsDNA-SYBR Green I (SGI), ion quencher, and analyte was designed for bioanalysis. The "filament" and switch of the lamp could be customized by employing different dsDNA and ion quencher. The poly(AT/TA) dsDNA was successfully screened as the most effective filament of the lamp. Two common ions, Hg 2+ and Fe 3+ , were selected as the model switch, and the corresponding ligand molecules cysteine (Cys) and pyrophosphate ions (PPi) were selected as the targets. When the fluorescence-quenched dsDNA/SGI-ion complex was introduced into a target-containing system, ions could be bound by competitive molecules and separate from the complex, thereby lighting the lamp. However, no light was observed if the biomolecule could not snatch the metal ions from the complex. Under the optimal conditions, sensitive and selective detection of Cys and PPi was achieved by the lamp, with practical applications in fetal bovine serum and human urine. This ion quencher regulated lamp for fluorescent bioassays is simple in design, fast in operation, and is more convenient than other methods. Significantly, as many molecules could form stable complexes with metal ions selectively, this ion quencher operated lamp has potential for the detection of a wide spectrum of analytes. Graphical abstract A novel and adjustable lamp on the basis of competitive interaction among dsDNA-SYBR Green I, ions quencher and analyte was designed for bioanalysis. The filament and switch of lamp could be customized by employing different dsDNA and ions quencher.

Vacuum ultraviolet emission characteristics from He-Ne-Xe gas discharge in an alternating current plasma display panel cell

NASA Astrophysics Data System (ADS)

Seo, Jeong Hyun; Jeong, Heui Seob; Lee, Joo Yul; Yoon, Cha Keun; Kim, Joong Kyun; Whang, Ki-Woong

2000-08-01

We measured the time integrated vacuum ultraviolet (VUV) emission spectra of He-Ne-Xe gas mixture from a surface type alternating current (ac) plasma display panel cell. The measured emission lines are the resonance line (147 nm) from Xe*(1s4), the first continuum (150 nm) and the second continuum (173 nm) from Xe dimer excited states. The relative intensities of VUV spectral lines from Xe* and Xe2* are dependent on the He/Ne mixing ratio as well as the Xe partial and total pressure. The intensity of 147 nm VUV increases with the Ne content increase and Xe2* molecular emission increases with the He content increase. Infrared (IR) spectra and the time variation of VUV were measured to explain the reaction pathway and the effect of the mixing ratio of He/Ne on the spectral intensity. A detailed study for the decay time shows that the decay time of 147 nm has two time constants and the radiation of 150 and 173 nm results mainly from Xe*(1s5). The IR spectra shows that the contribution from Xe**(>6 s) to Xe*(1s5) and Xe*(1s4) in He-Xe is different from that of Ne-Xe. The change of IR intensity explains the spectral intensity variations of He-Xe and Ne-Xe discharge.

An Analysis of Total Lightning Flash Rates Over Florida

NASA Astrophysics Data System (ADS)

Mazzetti, Thomas O.; Fuelberg, Henry E.

2017-12-01

Although Florida is known as the "Sunshine State", it also contains the greatest lightning flash densities in the United States. Flash density has received considerable attention in the literature, but lightning flash rate has received much less attention. We use data from the Earth Networks Total Lightning Network (ENTLN) to produce a 5 year (2010-2014) set of statistics regarding total flash rates over Florida and adjacent regions. Instead of tracking individual storms, we superimpose a 0.2° × 0.2° grid over the study region and count both cloud-to-ground (CG) and in-cloud (IC) flashes over 5 min intervals. Results show that the distribution of total flash rates is highly skewed toward small values, whereas the greatest rate is 185 flashes min-1. Greatest average annual flash rates ( 3 flashes min-1) are located near Orlando. The southernmost peninsula, North Florida, and the Florida Panhandle exhibit smaller average annual flash rates ( 1.5 flashes min-1). Large flash rates > 100 flashes min-1 can occur during any season, at any time during the 24 h period, and at any location within the domain. However, they are most likely during the afternoon and early evening in East Central Florida during the spring and summer months.

A global flash flood forecasting system

NASA Astrophysics Data System (ADS)

Baugh, Calum; Pappenberger, Florian; Wetterhall, Fredrik; Hewson, Tim; Zsoter, Ervin

2016-04-01

The sudden and devastating nature of flash flood events means it is imperative to provide early warnings such as those derived from Numerical Weather Prediction (NWP) forecasts. Currently such systems exist on basin, national and continental scales in Europe, North America and Australia but rely on high resolution NWP forecasts or rainfall-radar nowcasting, neither of which have global coverage. To produce global flash flood forecasts this work investigates the possibility of using forecasts from a global NWP system. In particular we: (i) discuss how global NWP can be used for flash flood forecasting and discuss strengths and weaknesses; (ii) demonstrate how a robust evaluation can be performed given the rarity of the event; (iii) highlight the challenges and opportunities in communicating flash flood uncertainty to decision makers; and (iv) explore future developments which would significantly improve global flash flood forecasting. The proposed forecast system uses ensemble surface runoff forecasts from the ECMWF H-TESSEL land surface scheme. A flash flood index is generated using the ERIC (Enhanced Runoff Index based on Climatology) methodology [Raynaud et al., 2014]. This global methodology is applied to a series of flash floods across southern Europe. Results from the system are compared against warnings produced using the higher resolution COSMO-LEPS limited area model. The global system is evaluated by comparing forecasted warning locations against a flash flood database of media reports created in partnership with floodlist.com. To deal with the lack of objectivity in media reports we carefully assess the suitability of different skill scores and apply spatial uncertainty thresholds to the observations. To communicate the uncertainties of the flash flood system output we experiment with a dynamic region-growing algorithm. This automatically clusters regions of similar return period exceedence probabilities, thus presenting the at-risk areas at a spatial

Fucosylation of LAMP-1 and LAMP-2 by FUT1 correlates with lysosomal positioning and autophagic flux of breast cancer cells.

PubMed

Tan, Keng-Poo; Ho, Ming-Yi; Cho, Huan-Chieh; Yu, John; Hung, Jung-Tung; Yu, Alice Lin-Tsing

2016-08-25

Alpha1,2-fucosyltransferases, FUT1 and FUT2, which transfer fucoses onto the terminal galactose of N-acetyl-lactosamine via α1,2-linkage have been shown to be highly expressed in various types of cancers. A few studies have shown the involvement of FUT1 substrates in tumor cell proliferation and migration. Lysosome-associated membrane protein 1, LAMP-1, has been reported to carry alpha1,2-fucosylated Lewis Y (LeY) antigens in breast cancer cells, however, the biological functions of LeY on LAMP-1 remain largely unknown. Whether or not its family member, LAMP-2, displays similar modifications and functions as LAMP-1 has not yet been addressed. In this study, we have presented evidence supporting that both LAMP-1 and 2 are substrates for FUT1, but not FUT2. We have also demonstrated the presence of H2 and LeY antigens on LAMP-1 by a targeted nanoLC-MS(3) and the decreased levels of fucosylation on LAMP-2 by MALDI-TOF analysis upon FUT1 knockdown. In addition, we found that the expression of LeY was substantial in less invasive ER+/PR+/HER- breast cancer cells (MCF-7 and T47D) but negligible in highly invasive triple-negative MDA-MB-231 cells, of which LeY levels were correlated with the levels of LeY carried by LAMP-1 and 2. Intriguingly, we also observed a striking change in the subcellular localization of lysosomes upon FUT1 knockdown from peripheral distribution of LAMP-1 and 2 to a preferential perinuclear accumulation. Besides that, knockdown of FUT1 led to an increased rate of autophagic flux along with diminished activity of mammalian target of rapamycin complex 1 (mTORC1) and enhanced autophagosome-lysosome fusion. This may be associated with the predominantly perinuclear distribution of lysosomes mediated by FUT1 knockdown as lysosomal positioning has been reported to regulate mTOR activity and autophagy. Taken together, our results suggest that downregulation of FUT1, which leads to the perinuclear localization of LAMP-1 and 2, is correlated with increased

Fucosylation of LAMP-1 and LAMP-2 by FUT1 correlates with lysosomal positioning and autophagic flux of breast cancer cells

PubMed Central

Tan, Keng-Poo; Ho, Ming-Yi; Cho, Huan-Chieh; Yu, John; Hung, Jung-Tung; Yu, Alice Lin-Tsing

2016-01-01

Alpha1,2-fucosyltransferases, FUT1 and FUT2, which transfer fucoses onto the terminal galactose of N-acetyl-lactosamine via α1,2-linkage have been shown to be highly expressed in various types of cancers. A few studies have shown the involvement of FUT1 substrates in tumor cell proliferation and migration. Lysosome-associated membrane protein 1, LAMP-1, has been reported to carry alpha1,2-fucosylated Lewis Y (LeY) antigens in breast cancer cells, however, the biological functions of LeY on LAMP-1 remain largely unknown. Whether or not its family member, LAMP-2, displays similar modifications and functions as LAMP-1 has not yet been addressed. In this study, we have presented evidence supporting that both LAMP-1 and 2 are substrates for FUT1, but not FUT2. We have also demonstrated the presence of H2 and LeY antigens on LAMP-1 by a targeted nanoLC-MS3 and the decreased levels of fucosylation on LAMP-2 by MALDI-TOF analysis upon FUT1 knockdown. In addition, we found that the expression of LeY was substantial in less invasive ER+/PR+/HER− breast cancer cells (MCF-7 and T47D) but negligible in highly invasive triple-negative MDA-MB-231 cells, of which LeY levels were correlated with the levels of LeY carried by LAMP-1 and 2. Intriguingly, we also observed a striking change in the subcellular localization of lysosomes upon FUT1 knockdown from peripheral distribution of LAMP-1 and 2 to a preferential perinuclear accumulation. Besides that, knockdown of FUT1 led to an increased rate of autophagic flux along with diminished activity of mammalian target of rapamycin complex 1 (mTORC1) and enhanced autophagosome–lysosome fusion. This may be associated with the predominantly perinuclear distribution of lysosomes mediated by FUT1 knockdown as lysosomal positioning has been reported to regulate mTOR activity and autophagy. Taken together, our results suggest that downregulation of FUT1, which leads to the perinuclear localization of LAMP-1 and 2, is correlated with

Hyperfine frequencies of {sup 87}Rb and {sup 133}Cs atoms in Xe gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

McGuyer, B. H.; Xia, T.; Jau, Y.-Y.

2011-09-15

The microwave resonant frequencies of ground-state {sup 87}Rb and {sup 133}Cs atoms in Xe buffer gas are shown to have a relatively large nonlinear dependence on the Xe pressure, presumably because of RbXe or CsXe van der Waals molecules. The nonlinear shifts for Xe are opposite in sign to the previously measured shifts for Ar and Kr, even though all three gases have negative linear shifts. The Xe data show striking discrepancies with the previous theory for nonlinear shifts. Most of this discrepancy is eliminated by accounting for the spin-rotation interaction, {gamma}N{center_dot}S, in addition to the hyperfine-shift interaction, {delta} Amore » I{center_dot}S, in the molecules. To the limit of our experimental accuracy, the shifts of {sup 87}Rb and {sup 133}Cs in He, Ne, and N{sub 2} were linear with pressure.« less

Simulation of flashing signal operations.

DOT National Transportation Integrated Search

1982-01-01

Various guidelines that have been proposed for the operation of traffic signals in the flashing mode were reviewed. The use of existing traffic simulation procedures to evaluate flashing signals was examined and a study methodology for simulating and...

Flash Inactivation of Oxygen Evolution

PubMed Central

Frasch, Wayne D.; Cheniae, George M.

1980-01-01

Brief saturating light flashes were used to probe the mechanism of inactivation of O2 evolution by Tris in chloroplasts. Maximum inactivation with a single flash and an oscillation with period of four on subsequent flashes was observed. Analyses of the oscillations suggested that only the charge-collecting O2-evolving catalyst of photosystem II (S2-state) was a target of inactivation by Tris. This conclusion was supported by the following observations: (a) hydroxylamine preequilibration caused a three-flash delay in the inactivation pattern; (b) the lifetimes of the Tris-inactivable and S2-states were similar; and (c) reagents accelerating S2 deactivation decreased the lifetime of the inactivable state. Inactivation proved to be moderated by F, the precursor of Signal IIs, as shown by a one flash delay with chloroplasts having high abundance of F. Evidence was obtained for cooperativity effects in inactivation and NH3 was shown to be a competitive inhibitor of the Tris-induced inactivation. S2-dependent inactivation was inhibited by glutaraldehyde fixation of chloroplasts, possibly suggesting that inactivation proceeds via conformational changes of the S2-state. PMID:16661270

An optimized microfabricated platform for the optical generation and detection of hyperpolarized 129Xe

PubMed Central

Kennedy, Daniel J.; Seltzer, Scott J.; Jiménez-Martínez, Ricardo; Ring, Hattie L.; Malecek, Nicolas S.; Knappe, Svenja; Donley, Elizabeth A.; Kitching, John; Bajaj, Vikram S.; Pines, Alexander

2017-01-01

Low thermal-equilibrium nuclear spin polarizations and the need for sophisticated instrumentation render conventional nuclear magnetic resonance (NMR) spectroscopy and imaging (MRI) incompatible with small-scale microfluidic devices. Hyperpolarized 129Xe gas has found use in the study of many materials but has required very large and expensive instrumentation. Recently a microfabricated device with modest instrumentation demonstrated all-optical hyperpolarization and detection of 129Xe gas. This device was limited by 129Xe polarizations less than 1%, 129Xe NMR signals smaller than 20 nT, and transport of hyperpolarized 129Xe over millimeter lengths. Higher polarizations, versatile detection schemes, and flow of 129Xe over larger distances are desirable for wider applications. Here we demonstrate an ultra-sensitive microfabricated platform that achieves 129Xe polarizations reaching 7%, NMR signals exceeding 1 μT, lifetimes up to 6 s, and simultaneous two-mode detection, consisting of a high-sensitivity in situ channel with signal-to-noise of 105 and a lower-sensitivity ex situ detection channel which may be useful in a wider variety of conditions. 129Xe is hyperpolarized and detected in locations more than 1 cm apart. Our versatile device is an optimal platform for microfluidic magnetic resonance in particular, but equally attractive for wider nuclear spin applications benefitting from ultra-sensitive detection, long coherences, and simple instrumentation. PMID:28266629

An optimized microfabricated platform for the optical generation and detection of hyperpolarized 129Xe

DOE PAGES

Kennedy, Daniel J.; Seltzer, Scott J.; Jiménez-Martínez, Ricardo; ...

2017-03-07

Low thermal-equilibrium nuclear spin polarizations and the need for sophisticated instrumentation render conventional nuclear magnetic resonance (NMR) spectroscopy and imaging (MRI) incompatible with small-scale microfluidic devices. Hyperpolarized 129Xe gas has found use in the study of many materials but has required very large and expensive instrumentation. Recently a microfabricated device with modest instrumentation demonstrated all-optical hyperpolarization and detection of 129Xe gas. This device was limited by 129Xe polarizations less than 1%, 129Xe NMR signals smaller than 20 nT, and transport of hyperpolarized 129Xe over millimeter lengths. Higher polarizations, versatile detection schemes, and flow of 129Xe over larger distances are desirablemore » for wider applications. Here we demonstrate an ultra-sensitive microfabricated platform that achieves 129Xe polarizations reaching 7%, NMR signals exceeding 1 μT, lifetimes up to 6 s, and simultaneous two-mode detection, consisting of a high-sensitivity in situ channel with signal-to-noise of 10 5 and a lower-sensitivity ex situ detection channel which may be useful in a wider variety of conditions. 129Xe is hyperpolarized and detected in locations more than 1 cm apart. Our versatile device is an optimal platform for microfluidic magnetic resonance in particular, but equally attractive for wider nuclear spin applications benefitting from ultra-sensitive detection, long coherences, and simple instrumentation.« less

Studies on Temperature Dependence of Rubidium Lamp for Atomic Frequency Standard

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghosal, Bikash; Banik, Alak; Vats, Vaibhav

2011-10-20

Rb lamp is a very critical component of the Rb atomic clock's Physics Package. The Rb lamp's performance is very sensitive to temperature and its stability. In this paper we discuss the behaviors of Rb Lamp with temperature. The Rb lamp exciter power and temperature of Rb bulb are very important parameters in controlling the performance of the Rb Lamp. It is observed that at temperatures beyond 110 deg. C, the lamp mode changes from the ring to red mode resulting in abnormal broadening of emission lines and self reversal. The results of our studies on spectral analysis of Rbmore » lamp under various operating conditions are reported in the paper.« less

LED traffic signal lamp characteristics : executive summary.

DOT National Transportation Integrated Search

2002-05-01

LED traffic signal lamps are being used to replace incandescent traffic signal lamps because of the long-term cost saving associated with reduced energy consumption and longer service life. The are reasons to believe that the use of LED traffic signa...

LED traffic signal lamp characteristics : final report.

DOT National Transportation Integrated Search

2002-05-01

LED traffic signal lamps are being used to replace incandescent traffic signal lamps because of : the long-term cost saving associated with reduced energy consumption and longer service life. The are reasons to believe that the use of LED traffic sig...

Study of high-j neutron excitations outside 136Xe

NASA Astrophysics Data System (ADS)

Talwar, R.; Kay, B. P.; Mitchell, A. J.; Adachi, S.; Entwisle, J. P.; Fujita, Y.; Gey, G.; Noji, S.; Ong, H. J.; Schiffer, J. P.; Tamii, A.

2017-09-01

The character of single-neutron excitations outside of N = 82 has been studied using nucleon transfer reactions in terms of the energy centroid of their strength as well as the fragmentation of this strength among the actual states of the nucleus. However, extending the systematic study of the N = 83 isotones to 137Xe has been challenging due to xenon being a gas at room temperature. Though several attempts have been made, a quantitative determination of the spectroscopic factors for the neutron 9/2- and 13/2+ excitations in 137Xe is still lacking. In the present work, we report on a study of the 136Xe(α,3He)137Xe reaction carried out at 100 MeV to probe the l = 5 , 9/2- and l = 6 , 13/2+ single-neutron excitations. The experimental technique and results will be presented discussing them in context of the evolution of these single-neutron excitations and the influence of the tensor interaction on the neutron single-particle states as the proton orbits are filling. This work has been supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under Contract Number DE-AC02-06CH11357, the Australian Research Council Discovery Project 120104176, and the UK Science and Technology Facilities.

Experimental ion mobility measurements in Xe-CO2

NASA Astrophysics Data System (ADS)

Cortez, A. F. V.; Santos, M. A. G.; Veenhof, R.; Patra, R. N.; Neves, P. N. B.; Santos, F. P.; Borges, F. I. G. M.; Conde, C. A. N.

2017-06-01

Data on ion mobility is important to improve the performance of large volume gaseous detectors. In the present work the method, experimental setup and results for the ion mobility measurements in Xe-CO2 mixtures are presented. The results for this mixture show the presence of only one peak for all gas ratios of Xe-CO2, low reduced electric fields, E/N, 10-25 Td (2.4-6.1 kV·cm-1·bar-1), low pressures 6-8 Torr (8-10.6 mbar), at room temperature.

Genetics Home Reference: fragile XE syndrome

MedlinePlus

... are so mild that the individuals function normally. Learning disabilities are the most common sign of impaired cognitive function in people with fragile XE syndrome . The learning disabilities are likely a result of communication and behavioral ...

Electrodeless discharge lamp is easily started, has high stability

NASA Technical Reports Server (NTRS)

Bell, W. E.; Bloom, A. L.

1966-01-01

Electrodeless discharge borosilicate glass lamp is used in various high-resolution optical systems. It is partially charged with krypton, contains small amounts of rubidium, and is enclosed in a hermetically sealed envelope that maintains the lamp at an optimum temperature during discharge. The lamp is quickly started by its excitation coil.

Trampoline motions in Xe-graphite(0 0 0 1) surface scattering

NASA Astrophysics Data System (ADS)

Watanabe, Yoshimasa; Yamaguchi, Hiroki; Hashinokuchi, Michihiro; Sawabe, Kyoichi; Maruyama, Shigeo; Matsumoto, Yoichiro; Shobatake, Kosuke

2005-09-01

We have investigated Xe scattering from the graphite(0 0 0 1) surface at hyperthermal incident energies using a molecular beam-surface scattering technique and molecular dynamics simulations. For all incident conditions, the incident Xe atom conserves the momentum parallel to the surface and loses approximately 80% of the normal incident energy. The weak interlayer potential of graphite disperses the deformation over the wide range of a graphene sheet. The dynamic corrugation induced by the collision is smooth even at hyperthermal incident energy; the graphene sheet moves like a trampoline net and the Xe atom like a trampoliner.

LED lamp power management system and method

DOEpatents

Gaines, James; Clauberg, Bernd; Van Erp, Josephus A. M.

2013-03-19

An LED lamp power management system and method including an LED lamp having an LED controller 58; a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 reduces power loss in one of the channel switch 62 and the shunt switch 68 when LED lamp electronics power loss (P.sub.loss) exceeds an LED lamp electronics power loss limit (P.sub.lim); and each of the channel switches 62 receives a channel switch control signal 63 from the LED controller 58 and each of the shunt switches 68 receives a shunt switch control signal 69 from the LED controller 58.

Test plane uniformity analysis for the MSFC solar simulator lamp array

NASA Technical Reports Server (NTRS)

Griner, D. B.

1976-01-01

A preliminary analysis was made on the solar simulator lamp array. It is an array of 405 tungsten halogen lamps with Fresnel lenses to achieve the required spectral distribution and collimation. A computer program was developed to analyze lamp array performance at the test plane. Measurements were made on individual lamp lens combinations to obtain data for the computer analysis. The analysis indicated that the performance of the lamp array was about as expected, except for a need to position the test plane within 2.7 m of the lamp array to achieve the desired 7 percent uniformity of illumination tolerance.

Gain measurements of the Ca-Xe charge exchange system. [for UV lasers

NASA Technical Reports Server (NTRS)

Michels, C. J.; Chubb, D. L.

1978-01-01

Charge-exchange-pumped Ca(+) was studied for possible positive laser gain at 370.6 and 315.9 nm using an Xe MPD arc as the Xe(+) source. The present paper describes the MPD arc, the calcium injection system, the diagnostics for gain, and spontaneous emission measurements and results. No positive gain measurements were observed. A small Xe-Ca charge exchange cross section compared to He-metal laser systems charge exchange cross sections is the most probable reason why the result was negative.

Bipolar cloud-to-ground lightning flash observations

NASA Astrophysics Data System (ADS)

Saba, Marcelo M. F.; Schumann, Carina; Warner, Tom A.; Helsdon, John H.; Schulz, Wolfgang; Orville, Richard E.

2013-10-01

lightning is usually defined as a lightning flash where the current waveform exhibits a polarity reversal. There are very few reported cases of cloud-to-ground (CG) bipolar flashes using only one channel in the literature. Reports on this type of bipolar flashes are not common due to the fact that in order to confirm that currents of both polarities follow the same channel to the ground, one necessarily needs video records. This study presents five clear observations of single-channel bipolar CG flashes. High-speed video and electric field measurement observations are used and analyzed. Based on the video images obtained and based on previous observations of positive CG flashes with high-speed cameras, we suggest that positive leader branches which do not participate in the initial return stroke of a positive cloud-to-ground flash later generate recoil leaders whose negative ends, upon reaching the branch point, traverse the return stroke channel path to the ground resulting in a subsequent return stroke of opposite polarity.

On Stellar Flash Echoes from Circular Rings

NASA Astrophysics Data System (ADS)

Nemiroff, Robert; Mukherjee, Oindabi

2018-01-01

A flash -- or any episode of variability -- that occurs in the vicinity of a circular ring might be seen several times later, simultaneously, as echoes on the ring. Effective images of the flash are created and annihilated in pairs, with as many as four flash images visible concurrently. Videos detailing sequences of image pair creation, tandem motion, and subsequent image annihilation are shown, given simple opacity and scattering assumptions. It is proven that, surprisingly, images from a second pair creation event always annihilate with images from the first. Caustic surfaces between flash locations yielding two and four images are computed. Although such ring echos surely occur, their practical detection might be difficult as it could require dedicated observing programs involving sensitive photometry of extended objects. Potential flash sources include planetary and interstellar gas and dust rings near and around variable stars, flare stars, novae, supernovae, and GRBs. Potentially recoverable information includes size, distance, temporal history, and angular isotropy of both the ring and flash.

ZIF-Derived Nitrogen-Doped Porous Carbons for Xe Adsorption and Separation

NASA Astrophysics Data System (ADS)

Zhong, Shan; Wang, Qian; Cao, Dapeng

2016-02-01

Currently, finding high capacity adsorbents with large selectivity to capture Xe is still a great challenge. In this work, nitrogen-doped porous carbons were prepared by programmable temperature carbonization of zeolitic imidazolate framework-8 (ZIF-8) and ZIF-8/xylitol composite precursors and the resultant samples are marked as Carbon-Z and Carbon-ZX, respectively. Further adsorption measurements indicate that ZIF-derived nitrogen-doped Carbon-ZX exhibits extremely high Xe capacity of 4.42 mmol g-1 at 298 K and 1 bar, which is higher than almost all other pristine MOFs such as CuBTC, Ni/DOBDC, MOF-5 and Al-MIL-53, and even more than three times of the matrix ZIF-8 at similar conditions. Moreover, Carbon-ZX also shows the highest Xe/N2 selectivity about ~120, which is much larger than all other reported MOFs. These remarkable features illustrate that ZIF-derived nitrogen-doped porous carbon is an excellent adsorbent for Xe adsorption and separation at room temperature.

Synthesis of the missing oxide of xenon, XeO2, and its implications for Earth's missing xenon.

PubMed

Brock, David S; Schrobilgen, Gary J

2011-04-27

The missing Xe(IV) oxide, XeO(2), has been synthesized at 0 °C by hydrolysis of XeF(4) in water and 2.00 M H(2)SO(4(aq)). Raman spectroscopy and (16/18)O isotopic enrichment studies indicate that XeO(2) possesses an extended structure in which Xe(IV) is oxygen bridged to four neighboring oxygen atoms to give a local square-planar XeO(4) geometry based on an AX(4)E(2) valence shell electron pair repulsion (VSEPR) arrangement. The vibrational spectra of Xe(16)O(2) and Xe(18)O(2) amend prior vibrational assignments of xenon doped SiO(2) and are in accordance with prior speculation that xenon depletion from the Earth's atmosphere may occur by xenon insertion at high temperatures and high pressures into SiO(2) in the Earth's crust.

Search for the permanent electric dipole moment of 129Xe

NASA Astrophysics Data System (ADS)

Sachdeva, Natasha; Chupp, Timothy; Gong, Fei; Babcock, Earl; Salhi, Zahir; Burghoff, Martin; Fan, Isaac; Killian, Wolfgang; Knappe-Grüneberg, Silvia; Schabel, Allard; Seifert, Frank; Trahms, Lutz; Voigt, Jens; Degenkolb, Skyler; Fierlinger, Peter; Krägeloh, Eva; Lins, Tobias; Marino, Michael; Meinel, Jonas; Niessen, Benjamin; Stuiber, Stefan; Terrano, William; Kuchler, Florian; Singh, Jaideep

2017-09-01

CP-violation in Beyond-the-Standard-Model physics, necessary to explain the baryon asymmetry, gives rise to permanent electric dipole moments (EDMs). EDM measurements of the neutron, electron, paramagnetic and diamagnetic atoms constrain CP-violating parameters. The current limit for the 129Xe EDM is 6 ×10-27 e . cm (95 % CL). The HeXeEDM experiment at FRM-II (Munich Research Reactor) and BMSR-2 (Berlin Magnetically Shielded Room) uses a stable magnetic field in a magnetically shielded room and 3He comagnetometer with potential to improve the limit by two orders of magnitude. Polarized 3He and 129Xe free precession is detected with SQUID magnetometers in the presence of applied electric and magnetic fields. Conclusions from recent measurements will be presented.

Long-term life testing of Geostationary Operational Environmental Satellite (GOES) encoder lamps

NASA Technical Reports Server (NTRS)

Powers, Charles E.

1992-01-01

The aging characteristics and lifetimes of tungsten filament encoder lamps were determined as a function of operating voltage and filament material. For pure tungsten and thoria doped (1 pct.) filament lamps, crystal grain growth over the center portion of the filament leads to the ultimate failure of the lamp. The development of notches associated with this grain growth is the cause of lamp burn out. Eventually, one of the notches will 'etch' through the filament, causing it to fail open. For rhenium doped (3 pct.) filament lamps, distortion of the filament leads to the ultimate failure of the lamp. The lifetime of these lamps is about 1 year at an operating voltage of 5.0 volts. The pure tungsten filament lamps have the longest average lifetime, and the thoria doped filament lamps have the shortest at 5.0 volts. The lifetimes of these lamps is about 7 years at an operating voltage of 3.5 volts. Data suggest that the rhenium doped lamps will have the longest average lifetime at 3.5 volts, and the thoria doped will have the shortest. These lifetimes are comparable to the desired lifetimes of 7 years.

Comparison of direct and alternating current vacuum ultraviolet lamps in atmospheric pressure photoionization.

PubMed

Vaikkinen, Anu; Haapala, Markus; Kersten, Hendrik; Benter, Thorsten; Kostiainen, Risto; Kauppila, Tiina J

2012-02-07

A direct current induced vacuum ultraviolet (dc-VUV) krypton discharge lamp and an alternating current, radio frequency (rf) induced VUV lamp that are essentially similar to lamps in commercial atmospheric pressure photoionization (APPI) ion sources were compared. The emission distributions along the diameter of the lamp exit window were measured, and they showed that the beam of the rf lamp is much wider than that of the dc lamp. Thus, the rf lamp has larger efficient ionization area, and it also emits more photons than the dc lamp. The ionization efficiencies of the lamps were compared using identical spray geometries with both lamps in microchip APPI mass spectrometry (μAPPI-MS) and desorption atmospheric pressure photoionization-mass spectrometry (DAPPI-MS). A comprehensive view on the ionization was gained by studying six different μAPPI solvent compositions, five DAPPI spray solvents, and completely solvent-free DAPPI. The observed reactant ions for each solvent composition were very similar with both lamps except for toluene, which showed a higher amount of solvent originating oxidation products with the rf lamp than with the dc lamp in μAPPI. Moreover, the same analyte ions were detected with both lamps, and thus, the ionization mechanisms with both lamps are similar. The rf lamp showed a higher ionization efficiency than the dc lamp in all experiments. The difference between the lamp ionization efficiencies was greatest when high ionization energy (IE) solvent compositions (IEs above 10 eV), i.e., hexane, methanol, and methanol/water, (1:1 v:v) were used. The higher ionization efficiency of the rf lamp is likely due to the larger area of high intensity light emission, and the resulting larger efficient ionization area and higher amount of photons emitted. These result in higher solvent reactant ion production, which in turn enables more efficient analyte ion production. © 2012 American Chemical Society

The Forensic Potential of Flash Memory

DTIC Science & Technology

2009-09-01

limit range of 10 to 100 years before data is lost [12]. 5. Flash Memory Logical Structure The logical structure of flash memory from least to...area is not standardized and is manufacturer specific. This information will be used by the wear leveling algorithms and as such will be proprietary...memory cells, the manufacturers of the flash implement a wear leveling algorithm . In contrast, a magnetic disk in an overwrite operation will reuse the

Lamp automatically switches to new filament on burnout

NASA Technical Reports Server (NTRS)

Ingle, W. B.

1966-01-01

Lamp with primary and secondary filaments has a means for automatic switching to the secondary filament at primary filament burnout. Lamp failures and resultant expenses during oscillograph printing are appreciably reduced.

Lamp of adjustable spectrum for photographic usage

NASA Astrophysics Data System (ADS)

Mazikowski, Adam; Feldzensztajn, Mateusz

2017-08-01

Photography is a unique rapidly growing interdisciplinary field encompassing aspects of science, art and technology. Expectations of photographers are steadily increasing with the development of technology. One of the areas playing a crucial role in photography is lighting. Consequently, several types of light sources for photographic use have been developed. The ongoing research in this field concentrates on lamps with tunable CCT (Correlated Color Temperature). In this paper, we present a lamp, which emission spectrum can be tailored without affecting the output luminous ux. Intended for photographic uses, the lamp is based on an integrating sphere and a selection of LEDs. As the LED drivers, DC-DC converters controlled by a Raspberry PI were applied. Design process, including the selection of LED wavelengths, is presented. Output characteristics of the lamp were measured using the setup containing the spectrometer. The results of these experiments show good agreement with the spectrum set on the microcomputer.

Laser generation of XeCl exciplex molecules in a longitudinal repetitively pulsed discharge in a Xe - CsCl mixture

NASA Astrophysics Data System (ADS)

Boichenko, A. M.; Klenovskii, M. S.

2015-12-01

By using the previously developed kinetic model, we have carried out simulations to study the possibility of laser generation of XeCl exciplex molecules in the working medium based on a mixture of Xe with CsCl vapours, excited by a longitudinal repetitively pulsed discharge. The formation mechanism of exciplex molecules in this mixture is fundamentally different from the formation mechanisms in the traditional mixtures of exciplex lasers. The conditions that make the laser generation possible are discussed. For these conditions, with allowance for available specific experimental conditions of the repetitively pulsed discharge excitation, we have obtained the calculated dependences of the power and efficiency of generation on the reflectivity of mirrors in a laser cavity.

Menopausal hot flashes and insulin resistance.

PubMed

Tuomikoski, Pauliina; Ylikorkala, Olavi; Mikkola, Tomi S

2012-10-01

Recent data have indicated that menopausal hot flashes may be a determinant for cardiovascular health. Therefore, we studied the impact of hot flashes on insulin resistance, one of the most powerful markers of cardiovascular health, in recently postmenopausal women. We studied 143 recently postmenopausal (amenorrhea 6-36 mo) healthy and normal-weight women without previous hormone therapy use. The women prospectively recorded the number and severity of hot flashes for 2 weeks, and a validated total symptom score, the hot flash weekly weighted score, was calculated for each woman. Insulin resistance was assessed from fasting blood levels of glucose and insulin with the homeostasis model assessment. In 12 women, the assessment of insulin (n = 11) or glucose (n = 1) failed, and they were excluded from further analysis. Thus, hot flashes were absent in 19, mild in 32, moderate in 27, and severe in 53 women. The levels of glucose or insulin, or HOMA showed no differences between these groups, nor was insulin resistance related to the number or severity of hot flashes or to the levels of C-reactive protein or sex hormone-binding globulin. Overall, insulin resistance showed a positive association with body mass index (mean difference, 0.058; 95% CI, 0.015-0.102; P = 0.009) and a negative association with level of estradiol (mean difference, -0.002; 95% CI, -0.003 to -0.001; P = 0.009). Insulin resistance may not be involved in hot flash-related changes in cardiovascular health. However, because of the small sample size, these findings need to be interpreted with caution.

Electro-optical muzzle flash detection

NASA Astrophysics Data System (ADS)

Krieg, Jürgen; Eisele, Christian; Seiffer, Dirk

2016-10-01

Localizing a shooter in a complex scenario is a difficult task. Acoustic sensors can be used to detect blast waves. Radar technology permits detection of the projectile. A third method is to detect the muzzle flash using electro-optical devices. Detection of muzzle flash events is possible with focal plane arrays, line and single element detectors. In this paper, we will show that the detection of a muzzle flash works well in the shortwave infrared spectral range. Important for the acceptance of an operational warning system in daily use is a very low false alarm rate. Using data from a detector with a high sampling rate the temporal signature of a potential muzzle flash event can be analyzed and the false alarm rate can be reduced. Another important issue is the realization of an omnidirectional view required on an operational level. It will be shown that a combination of single element detectors and simple optics in an appropriate configuration is a capable solution.

49 CFR 234.217 - Flashing light units.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Flashing light units. 234.217 Section 234.217... light units. (a) Each flashing light unit shall be properly positioned and aligned and shall be visible to a highway user approaching the crossing. (b) Each flashing light unit shall be maintained to...

340nm UV LED excitation in time-resolved fluorescence system for europium-based immunoassays detection

NASA Astrophysics Data System (ADS)

Rodenko, Olga; Fodgaard, Henrik; Tidemand-Lichtenberg, Peter; Pedersen, Christian

2017-02-01

In immunoassay analyzers for in-vitro diagnostics, Xenon flash lamps have been widely used as excitation light sources. Recent advancements in UV LED technology and its advantages over the flash lamps such as smaller footprint, better wall-plug efficiency, narrow emission spectrum, and no significant afterglow, have made them attractive light sources for gated detection systems. In this paper, we report on the implementation of a 340 nm UV LED based time-resolved fluorescence system based on europium chelate as a fluorescent marker. The system performance was tested with the immunoassay based on the cardiac marker, TnI. The same signal-to-noise ratio as for the flash lamp based system was obtained, operating the LED below specified maximum current. The background counts of the system and its main contributors were measured and analyzed. The background of the system of the LED based unit was improved by 39% compared to that of the Xenon flash lamp based unit, due to the LEDs narrower emission spectrum and longer pulse width. Key parameters of the LED system are discussed to further optimize the signal-to-noise ratio and signal-to-background, and hence the sensitivity of the instrument.

Heat transfer assembly for a fluorescent lamp and fixture

DOEpatents

Siminovitch, M.J.; Rubenstein, F.M.; Whitman, R.E.

1992-12-29

In a lighting fixture including a lamp and a housing, a heat transfer structure is disclosed for reducing the minimum lamp wall temperature of a fluorescent light bulb. The heat transfer structure, constructed of thermally conductive material, extends from inside the housing to outside the housing, transferring heat energy generated from a fluorescent light bulb to outside the housing where the heat energy is dissipated to the ambient air outside the housing. Also disclosed is a method for reducing minimum lamp wall temperatures. Further disclosed is an improved lighting fixture including a lamp, a housing and the aforementioned heat transfer structure. 11 figs.

Heat transfer assembly for a fluorescent lamp and fixture

DOEpatents

Siminovitch, Michael J.; Rubenstein, Francis M.; Whitman, Richard E.

1992-01-01

In a lighting fixture including a lamp and a housing, a heat transfer structure is disclosed for reducing the minimum lamp wall temperature of a fluorescent light bulb. The heat transfer structure, constructed of thermally conductive material, extends from inside the housing to outside the housing, transferring heat energy generated from a fluorescent light bulb to outside the housing where the heat energy is dissipated to the ambient air outside the housing. Also disclosed is a method for reducing minimum lamp wall temperatures. Further disclosed is an improved lighting fixture including a lamp, a housing and the aforementioned heat transfer structure.

Onset conditions for flash sintering of UO 2

DOE PAGES

Raftery, Alicia M.; Pereira da Silva, João Gustavo; Byler, Darrin D.; ...

2017-06-22

In this paper, flash sintering was demonstrated on stoichiometric and non-stoichiometric uranium dioxide pellets at temperatures ranging from room temperature (26°C) up to 600°C. The onset conditions for flash sintering were determined for three stoichiometries (UO 2.00, UO 2.08, and UO 2.16) and analyzed against an established thermal runaway model. The presence of excess oxygen was found to enhance the flash sintering onset behavior of uranium dioxide, lowering the field required to flash and shortening the time required for a flash to occur. Finally, the results from this study highlight the effect of stoichiometry on the flash sintering behavior ofmore » uranium dioxide and will serve as the foundation for future studies on this material.« less

Onset conditions for flash sintering of UO2

NASA Astrophysics Data System (ADS)

Raftery, Alicia M.; Pereira da Silva, João Gustavo; Byler, Darrin D.; Andersson, David A.; Uberuaga, Blas P.; Stanek, Christopher R.; McClellan, Kenneth J.

2017-09-01

In this work, flash sintering was demonstrated on stoichiometric and non-stoichiometric uranium dioxide pellets at temperatures ranging from room temperature (26 °C) up to 600 °C . The onset conditions for flash sintering were determined for three stoichiometries (UO2.00, UO2.08, and UO2.16) and analyzed against an established thermal runaway model. The presence of excess oxygen was found to enhance the flash sintering onset behavior of uranium dioxide, lowering the field required to flash and shortening the time required for a flash to occur. The results from this study highlight the effect of stoichiometry on the flash sintering behavior of uranium dioxide and will serve as the foundation for future studies on this material.

LAMPS software and mesoscale prediction studies

NASA Technical Reports Server (NTRS)

Perkey, D. J.

1985-01-01

The full-physics version of the LAMPS model has been implemented on the Perkin-Elmer computer. In Addition, LAMPS graphics processors have been rewritten to the run on the Perkin-Elmer and they are currently undergoing final testing. Numerical experiments investigating the impact of convective parameterized latent heat release on the evolution of a precipitating storm have been performed and the results are currently being evaluated. Curent efforts include the continued evaluation of the impact of initial conditions on LAMPS model results. This work will help define measurement requirements for future research field projects as well as for observations in support of operational forecasts. Also, the impact of parameterized latent heat on the evolution of precipitating systems is continuing. This research is in support of NASA's proposed Earth Observation Mission (EOM).

Retinal slit lamp video mosaicking.

PubMed

De Zanet, Sandro; Rudolph, Tobias; Richa, Rogerio; Tappeiner, Christoph; Sznitman, Raphael

2016-06-01

To this day, the slit lamp remains the first tool used by an ophthalmologist to examine patient eyes. Imaging of the retina poses, however, a variety of problems, namely a shallow depth of focus, reflections from the optical system, a small field of view and non-uniform illumination. For ophthalmologists, the use of slit lamp images for documentation and analysis purposes, however, remains extremely challenging due to large image artifacts. For this reason, we propose an automatic retinal slit lamp video mosaicking, which enlarges the field of view and reduces amount of noise and reflections, thus enhancing image quality. Our method is composed of three parts: (i) viable content segmentation, (ii) global registration and (iii) image blending. Frame content is segmented using gradient boosting with custom pixel-wise features. Speeded-up robust features are used for finding pair-wise translations between frames with robust random sample consensus estimation and graph-based simultaneous localization and mapping for global bundle adjustment. Foreground-aware blending based on feathering merges video frames into comprehensive mosaics. Foreground is segmented successfully with an area under the curve of the receiver operating characteristic curve of 0.9557. Mosaicking results and state-of-the-art methods were compared and rated by ophthalmologists showing a strong preference for a large field of view provided by our method. The proposed method for global registration of retinal slit lamp images of the retina into comprehensive mosaics improves over state-of-the-art methods and is preferred qualitatively.

Angle Performance on Optima XE

DOE Office of Scientific and Technical Information (OSTI.GOV)

David, Jonathan; Satoh, Shu

2011-01-07

Angle control on high energy implanters is important due to shrinking device dimensions, and sensitivity to channeling at high beam energies. On Optima XE, beam-to-wafer angles are controlled in both the horizontal and vertical directions. In the horizontal direction, the beam angle is measured through a series of narrow slits, and any angle adjustment is made by steering the beam with the corrector magnet. In the vertical direction, the beam angle is measured through a high aspect ratio mask, and any angle adjustment is made by slightly tilting the wafer platen during implant.Using a sensitive channeling condition, we were ablemore » to quantify the angle repeatability of Optima XE. By quantifying the sheet resistance sensitivity to both horizontal and vertical angle variation, the total angle variation was calculated as 0.04 deg. (1{sigma}). Implants were run over a five week period, with all of the wafers selected from a single boule, in order to control for any crystal cut variation.« less

Abdominal adiposity and hot flashes among midlife women.

PubMed

Thurston, Rebecca C; Sowers, MaryFran R; Sutton-Tyrrell, Kim; Everson-Rose, Susan A; Lewis, Tené T; Edmundowicz, Daniel; Matthews, Karen A

2008-01-01

Two competing hypotheses suggest how adiposity may affect menopausal hot flashes. The "thin hypothesis" asserts that aromatization of androgens to estrogens in body fat should be associated with decreased hot flashes. Conversely, thermoregulatory models argue that body fat should be associated with increased hot flashes. The study objective was to examine associations between abdominal adiposity and hot flashes, including the role of reproductive hormones in these associations. The Study of Women's Health Across the Nation Heart Study (2001-2003) is an ancillary study to the Study of Women's Health Across the Nation, a community-based cohort study. Participants were 461 women (35% African American, 65% white) ages 45 to 58 years with an intact uterus and at least one ovary. Measures included a computed tomography scan to assess abdominal adiposity; reported hot flashes over the previous 2 weeks; and a blood sample for measurement of follicle-stimulating hormone, estradiol, and sex hormone-binding globulin-adjusted estradiol (free estradiol index). Associations were evaluated within multivariable logistic and linear regression models. Every 1-SD increase in total (odds ratio [OR]=1.28; 95% CI: 1.06-1.55) and subcutaneous (OR=1.30; 95% CI: 1.07-1.58) abdominal adiposity was associated with increased odds of hot flashes in age- and site-adjusted models. Visceral adiposity was not associated with hot flashes. Associations were not reduced when models included reproductive hormone concentrations. Increased abdominal adiposity, particularly subcutaneous adiposity, is associated with increased odds of hot flashes, favoring thermoregulatory models of hot flashes. Body fat may not protect women from hot flashes as once thought.

Light-Shifts of an Integrated Filter-Cell Rubidium Atomic Clock

DTIC Science & Technology

2015-05-25

the light-shift coefficient for two different rf- discharge lamps (i.e., a pure 87Rb lamp and a lamp filled with the natural Rb isotope abundance...for the Galileo Rb clock under the assumption of a natural (or 85Rb isotopically enriched) rf- discharge lamp for the Galileo clock. I...satellites [14]. 6.8347… GHz 85Rb Filter Cell Cell Resonance Photodiode Microwave Cavity 87Rb Discharge Lamp 87Rb & N2 Rb & Xe, Kr Optical Pumping 87Rb

Purging means and method for Xenon arc lamps

NASA Technical Reports Server (NTRS)

Miller, C. G. (Inventor)

1973-01-01

High pressure Xenon short-arc lamp with two reservoirs which are selectively connectable to the lamp's envelope is described. One reservoir contains an absorbent which will absorb both Xenon and contaminant gases such as CO2 and O2. The absorbent temperature is controlled to evacuate the envelope of both the Xenon and the contaminant gases. The temperature of the absorbent is then raised to desorb only clean Xenon while retaining the contaminant gases, thereby clearing the envelope of the contaminant gases. The second reservoir contains a gas whose specific purpose is, to remove the objectional metal film which deposits gradually on the interior surface of the lamp envelope during normal arc operation. The origin of the film is metal transferred from the cathode of the arc lamp by sputtering or other gas transfer processes.

High frequency inductive lamp and power oscillator

DOEpatents

MacLennan, Donald A.; Dymond, Jr., Lauren E.; Gitsevich, Aleksandr; Grimm, William G.; Kipling, Kent; Kirkpatrick, Douglas A.; Ola, Samuel A.; Simpson, James E.; Trimble, William C.; Tsai, Peter; Turner, Brian P.

2001-01-01

A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and I or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to adjust the driving frequency of the oscillator.

Color Degradation of Textiles with Natural Dyes and of Blue Scale Standards Exposed to White LED Lamps:Evaluation of White LED Lamps for Effectiveness as Museum Lighting

NASA Astrophysics Data System (ADS)

Ishii, Mie; Moriyama, Takayoshi; Toda, Masahiro; Kohmoto, Kohtaro; Saito, Masako

White light-emitting diodes (LED) are well suited for museum lighting because they emit neither UV nor IR radiation, which damage artifacts. The color degradation of natural dyes and blue scale standards (JIS L 0841) by white LED lamps are examined, and the performance of white LED lamps for museum lighting is evaluated. Blue scale standard grades 1-6 and silk fabrics dyed with 22 types of natural dyes classified as mid to highly responsive in a CIE technical report (CIE157:2004) were exposed to five types of white LED lamps using different luminescence methods and color temperatures. Color changes were measured at each 15000 lx·hr (500 lx at fabric surface × 300 hr) interval ten times. The accumulated exposure totaled 150000 lx·hr. The data on conventional white LED lamps and previously reported white fluorescent (W) and museum fluorescent (NU) lamps was evaluated. All the white LED lamps showed lower fading rates compared with a W lamp on a blue scale grade 1. The fading rate of natural dyes in total was the same between an NU lamp (3000 K) and a white LED lamp (2869 K). However, yellow natural dyes showed higher fading rates with the white LED lamp. This tendency is due to the high power characteristic of the LED lamp around 400-500 nm, which possibly contributes to the photo-fading action on the dyes. The most faded yellow dyes were Ukon (Curcuma longa L.) and Kihada (Phellodendron amurense Rupr.), and these are frequently used in historic artifacts such as kimono, wood-block prints, and scrolls. From a conservation point of view, we need to continue research on white LED lamps for use in museum lighting.

146. DETAIL VIEW, LOOKING STRAIGHT ON, OF CAST IRON LAMP ...

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

146. DETAIL VIEW, LOOKING STRAIGHT ON, OF CAST IRON LAMP STANDARD. THIS AND OTHER LAMP STANDARDS WERE REMOVED FROM THE LAMP COLUMNS ON THE PARAPET WALLS DURING WORLD WAR II AND STORED INSIDE THE DAM (January 1991) - Coolidge Dam, Gila River, Peridot, Gila County, AZ

49 CFR 392.33 - Obscured lamps or reflective devices/material.

Code of Federal Regulations, 2010 CFR

2010-10-01

... MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER SAFETY REGULATIONS DRIVING OF COMMERCIAL MOTOR VEHICLES Use of Lighted Lamps and Reflectors § 392.33 Obscured lamps or reflective devices/material. (a) No commercial motor vehicle shall be driven when any of the lamps...

An analysis of lamp irradiation in ellipsoidal mirror furnaces

NASA Astrophysics Data System (ADS)

Rivas, Damián; Vázquez-Espí, Carlos

2001-03-01

The irradiation generated by halogen lamps in ellipsoidal mirror furnaces is analyzed, in configurations suited to the study of the floating-zone technique for crystal growth in microgravity conditions. A line-source model for the lamp (instead of a point source) is developed, so that the longitudinal extent of the filament is taken into account. With this model the case of defocussed lamps can be handle analytically. In the model the lamp is formed by an aggregate of point-source elements, placed along the axis of the ellipsoid. For these point sources (which, in general, are defocussed) an irradiation model is formulated, within the approximation of geometrical optics. The irradiation profiles obtained (both on the lateral surface and on the inner base of the cylindrical sample) are analyzed. They present singularities related to the caustics formed by the family of reflected rays; these caustics are also analyzed. The lamp model is combined with a conduction-radiation model to study the temperature field in the sample. The effects of defocussing the lamp (common practice in crystal growth) are studied; advantages and also some drawbacks are pointed out. Comparison with experimental results is made.

Treatment of alopecia areata with 308-nm excimer lamp.

PubMed

Ohtsuki, Akiko; Hasegawa, Toshio; Ikeda, Shigaku

2010-12-01

Alopecia areata is considered to be a T-cell mediated autoimmune disorder. The 308-nm excimer lamp is thought to be capable of inducing T-cell apoptosis in vitro, suggesting that the lamp might be effective for the treatment of alopecia areata. We examined the effectiveness of the 308-nm excimer lamp for the treatment of alopecia areata. We recruited three patients with single alopecia areata lesions that were resistant to conventional treatment. The lesions were exposed to a 308-nm excimer lamp at 2-weekly intervals. Hair regrowth was observed in all three patients after approximately 10 treatment sessions. Our study showed that exposure to the 308-nm excimer lamp effectively induced hair regrowth in solitary alopecia areata lesions. Apart from erythema, there were no significant adverse effects. Therefore, we suggest that it may be considered as a treatment modality for recalcitrant alopecia areata. © 2010 Japanese Dermatological Association.

Na + Xe collisions in the presence of two nonresonant lasers

NASA Technical Reports Server (NTRS)

De Vries, P. L.; Chang, C. H.; George, T. F.; Laskowski, B.; Stallcop, J. R.

1980-01-01

Na+Xe collisions in the presence of two distinct laser fields (rhodamine 110 and Nd:glass) are investigated with reference to the response to nonresonant radiation of alkali metals collisionally perturbed by a buffer gas. It is found that the excited Na-asterisk (4s)+Xe state is produced with a measurable cross section due to two-photon absorption with field intensities as low as 10 MW/sq cm.

"Know What to Do If You Encounter a Flash Flood": Mental Models Analysis for Improving Flash Flood Risk Communication and Public Decision Making.

PubMed

Lazrus, Heather; Morss, Rebecca E; Demuth, Julie L; Lazo, Jeffrey K; Bostrom, Ann

2016-02-01

Understanding how people view flash flood risks can help improve risk communication, ultimately improving outcomes. This article analyzes data from 26 mental models interviews about flash floods with members of the public in Boulder, Colorado, to understand their perspectives on flash flood risks and mitigation. The analysis includes a comparison between public and professional perspectives by referencing a companion mental models study of Boulder-area professionals. A mental models approach can help to diagnose what people already know about flash flood risks and responses, as well as any critical gaps in their knowledge that might be addressed through improved risk communication. A few public interviewees mentioned most of the key concepts discussed by professionals as important for flash flood warning decision making. However, most interviewees exhibited some incomplete understandings and misconceptions about aspects of flash flood development and exposure, effects, or mitigation that may lead to ineffective warning decisions when a flash flood threatens. These include important misunderstandings about the rapid evolution of flash floods, the speed of water in flash floods, the locations and times that pose the greatest flash flood risk in Boulder, the value of situational awareness and environmental cues, and the most appropriate responses when a flash flood threatens. The findings point to recommendations for ways to improve risk communication, over the long term and when an event threatens, to help people quickly recognize and understand threats, obtain needed information, and make informed decisions in complex, rapidly evolving extreme weather events such as flash floods. © 2015 Society for Risk Analysis.

OTD Observations of Continental US Ground and Cloud Flashes

NASA Technical Reports Server (NTRS)

Koshak, William

2007-01-01

Lightning optical flash parameters (e.g., radiance, area, duration, number of optical groups, and number of optical events) derived from almost five years of Optical Transient Detector (OTD) data are analyzed. Hundreds of thousands of OTD flashes occurring over the continental US are categorized according to flash type (ground or cloud flash) using US National Lightning Detection Network TM (NLDN) data. The statistics of the optical characteristics of the ground and cloud flashes are inter-compared on an overall basis, and as a function of ground flash polarity. A standard two-distribution hypothesis test is used to inter-compare the population means of a given lightning parameter for the two flash types. Given the differences in the statistics of the optical characteristics, it is suggested that statistical analyses (e.g., Bayesian Inference) of the space-based optical measurements might make it possible to successfully discriminate ground and cloud flashes a reasonable percentage of the time.

Facile Thermal and Optical Ignition of Silicon Nanoparticles and Micron Particles.

PubMed

Huang, Sidi; Parimi, Venkata Sharat; Deng, Sili; Lingamneni, Srilakshmi; Zheng, Xiaolin

2017-10-11

Silicon (Si) particles are widely utilized as high-capacity electrodes for Li-ion batteries, elements for thermoelectric devices, agents for bioimaging and therapy, and many other applications. However, Si particles can ignite and burn in air at elevated temperatures or under intense illumination. This poses potential safety hazards when handling, storing, and utilizing these particles for those applications. In order to avoid the problem of accidental ignition, it is critical to quantify the ignition properties of Si particles such as their sizes and porosities. To do so, we first used differential scanning calorimetry to experimentally determine the reaction onset temperature of Si particles under slow heating rates (∼0.33 K/s). We found that the reaction onset temperature of Si particles increased with the particle diameter from 805 °C at 20-30 nm to 935 °C at 1-5 μm. Then, we used a xenon (Xe) flash lamp to ignite Si particles under fast heating rates (∼10 3 to 10 6 K/s) and measured the minimum ignition radiant fluence (i.e., the radiant energy per unit surface area of Si particle beds required for ignition). We found that the measured minimum ignition radiant fluence decreased with decreasing Si particle size and was most sensitive to the porosity of the Si particle bed. These trends for the Xe flash ignition experiments were also confirmed by our one-dimensional unsteady simulation to model the heat transfer process. The quantitative information on Si particle ignition included in this Letter will guide the safe handling, storage, and utilization of Si particles for diverse applications and prevent unwanted fire hazards.

Low-frequency Raman scattering in a Xe hydrate.

PubMed

Adichtchev, S V; Belosludov, V R; Ildyakov, A V; Malinovsky, V K; Manakov, A Yu; Subbotin, O S; Surovtsev, N V

2013-09-12

The physics of gas hydrates are rich in interesting phenomena such as anomalies for thermal conductivity, self-preservation effects for decomposition, and others. Some of these phenomena are presumably attributed to the resonance interaction of the rattling motions of guest molecules or atoms with the lattice modes. This can be expected to induce some specific features in the low-frequency (THz) vibrational response. Here we present results for low-frequency Raman scattering in a Xe hydrate, supported by numerical calculations of vibrational density of states. A number of narrow lines, located in the range from 18 to 90 cm(-1), were found in the Raman spectrum. Numerical calculations confirm that these lines correspond to resonance modes of the Xe hydrate. Also, low-frequency Raman scattering was studied during gas hydrate decomposition, and two scenarios were observed. The first one is the direct decomposition of the Xe hydrate to water and gas. The second one is the hydrate decomposition to ice and gas with subsequent melting of ice. In the latter case, a transient low-frequency Raman band is observed, which is associated with low-frequency bands (e.g., boson peak) of disordered solids.

Primer of School Lighting Lamps and Maintenance.

ERIC Educational Resources Information Center

Allphin, Willard

The basic principles of the most commonly used lamp types and the circuitry which makes them operate are discussed. The two objectives of this book are to serve as a--(1) guide to economical lighting, and (2) a permanent reference source for troubleshooting. Areas dealt with include--(1) lighting fundamentals, (2) incandescent lamps, (3)…

Flash sintering of ceramic materials

NASA Astrophysics Data System (ADS)

Dancer, C. E. J.

2016-10-01

During flash sintering, ceramic materials can sinter to high density in a matter of seconds while subjected to electric field and elevated temperature. This process, which occurs at lower furnace temperatures and in shorter times than both conventional ceramic sintering and field-assisted methods such as spark plasma sintering, has the potential to radically reduce the power consumption required for the densification of ceramic materials. This paper reviews the experimental work on flash sintering methods carried out to date, and compares the properties of the materials obtained to those produced by conventional sintering. The flash sintering process is described for oxides of zirconium, yttrium, aluminium, tin, zinc, and titanium; silicon and boron carbide, zirconium diboride, materials for solid oxide fuel applications, ferroelectric materials, and composite materials. While experimental observations have been made on a wide range of materials, understanding of the underlying mechanisms responsible for the onset and latter stages of flash sintering is still elusive. Elements of the proposed theories to explain the observed behaviour include extensive Joule heating throughout the material causing thermal runaway, arrested by the current limitation in the power supply, and the formation of defect avalanches which rapidly and dramatically increase the sample conductivity. Undoubtedly, the flash sintering process is affected by the electric field strength, furnace temperature and current density limit, but also by microstructural features such as the presence of second phase particles or dopants and the particle size in the starting material. While further experimental work and modelling is still required to attain a full understanding capable of predicting the success of the flash sintering process in different materials, the technique non-etheless holds great potential for exceptional control of the ceramic sintering process.

Guidelines for application of fluorescent lamps in high-performance avionic backlight systems

NASA Astrophysics Data System (ADS)

Syroid, Daniel D.

1997-07-01

Fluorescent lamps have proven to be well suited for use in high performance avionic backlight systems as demonstrated by numerous production applications for both commercial and military cockpit displays. Cockpit display applications include: Boeing 777, new 737s, F-15, F-16, F-18, F-22, C- 130, Navy P3, NASA Space Shuttle and many others. Fluorescent lamp based backlights provide high luminance, high lumen efficiency, precision chromaticity and long life for avionic active matrix liquid crystal display applications. Lamps have been produced in many sizes and shapes. Lamp diameters range from 2.6 mm to over 20 mm and lengths for the larger diameter lamps range to over one meter. Highly convoluted serpentine lamp configurations are common as are both hot and cold cathode electrode designs. This paper will review fluorescent lamp operating principles, discuss typical requirements for avionic grade lamps, compare avionic and laptop backlight designs and provide guidelines for the proper application of lamps and performance choices that must be made to attain optimum system performance considering high luminance output, system efficiency, dimming range and cost.

Helium shell flashes and evolution of accreting white dwarfs

NASA Astrophysics Data System (ADS)

Fujimoto, M. Y.; Sugimoto, D.

1982-06-01

The evolution of accreting white dwarfs is investigated from the onset of accretion through the helium shell flash. Properties of the helium shell flashes are studied by means of a generalized theory of shell flash and by numerical computations, and it is found that the shell flash grows up to the strength of a supernova explosion when the mass of the helium zone is large enough on a massive white dwarf. Although accretion onto a hot white dwarf causes a weaker shell flash than those onto cool ones, a strong tendency exists for the strength to be determined mainly by the accretion rate. For fast accretion, the shell flashes are weak and triggered recurrently, while for slow accretion the helium shell flash, once triggered, develops into a detonation supernova.

Evaluation of Flash Bainite in 4130 Steel

DTIC Science & Technology

2011-07-01

Technical Report ARWSB-TR-11011 Evaluation of Flash Bainite in 4130 Steel G. Vigilante M. Hespos S. Bartolucci...4. TITLE AND SUBTITLE Evaluation of Flash Bainite in 4130 Steel 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...need to be addressed, the Flash Bainite processing of 4130 steel demonstrates promise for applications needing a combination of high strength with

Experimental ion mobility measurements in Xe-CH4

NASA Astrophysics Data System (ADS)

Perdigoto, J. M. C.; Cortez, A. F. V.; Veenhof, R.; Neves, P. N. B.; Santos, F. P.; Borges, F. I. G. M.; Conde, C. A. N.

2017-09-01

Data on ion mobility is important to improve the performance of large volume gaseous detectors. In the present work, the method, experimental setup and results for the ion mobility measurements in Xe-CH4 mixtures are presented. The results for this mixture show the presence of two distinct groups of ions. The nature of the ions depend on the mixture ratio since they are originated by both Xe and CH4. The results here presented were obtained for low reduced electric fields, E/N, 10-25 Td (2.4-6.1 kV ṡ cm-1 ṡ bar-1), at low pressure (8 Torr) (10.6 mbar), and at room temperature.

CALiPER Application Summary Report 21. Linear (T8) LED Lamps

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2014-03-01

This report focuses on the bare lamp performance of 31 linear LED lamps intended as an alternative to T8 fluorescent lamps. Data obtained in accordance with IES LM-79-08 indicated that the mean efficacy is similar to that of fluorescent lamps, but that lumen output is often much lower. This presents a situation where something must change in order for energy savings and equivalent illumination levels to be achieved simultaneously. In this case, the luminous intensity distribution of all the tested lamps was directional or semi-directional, rather than omnidirectional. Also discussed in this report are several issues related to the electricalmore » configuration of the lamps, such as the required socket types and power feed location. While no configuration is necessarily better, the multitude of options can make specifying and installing linear LED lamps more difficult, with the potential for safety issues. Similarly, the variety of color and power quality attributes adds a layer of complexity to the specification process. Many products offered good or excellent quality attributes, but some did not and thus could be perceived as inferior to fluorescent lamps in some installations.« less

Arc lamp power supply using a voltage multiplier

NASA Technical Reports Server (NTRS)

Leighty, Bradley D.

1988-01-01

A power supply is provided for an arc discharge lamp which includes a relatively low voltage high current power supply section and a high voltage starter circuit. The low voltage section includes a transformer, rectifier, variable resistor and a bank of capacitors, while the starter circuit comprises several diodes and capacitors connected as a Cockcroft-Walton multiplier. The starting circuit is effectively bypassed when the lamp arc is established and serves to automatically provide a high starting voltage to re-strike the lamp arc if the arc is extinguished by a power interruption.

Anxiogenic CO2 Stimulus Elicits Exacerbated Hot Flash-like Responses in a Rat Menopause Model and Hot Flashes in Menopausal Women

PubMed Central

Federici, Lauren M.; Roth, Sarah Dorsey; Krier, Connie; Fitz, Stephanie D.; Skaar, Todd; Shekhar, Anantha; Carpenter, Janet S.; Johnson, Philip L.

2016-01-01

Objective Since longitudinal studies determined that anxiety is a strong risk factor for hot flashes, we hypothesized that an anxiogenic stimulus that signals air hunger (hypercapnic, normoxic gas) would trigger an exacerbated hot flash-associated increase in tail skin temperature (TST) in a rat ovariectomy (OVEX) model of surgical menopause and hot flashes in symptomatic menopausal women. We also assessed TST responses in OVEX serotonin transporter (SERT)+/− rats that models a common polymorphism that is associated with increased climacteric symptoms in menopausal women and increases in anxiety traits. Methods OVEX and sham-OVEX rats (initial experiment) and wildtype and SERT+/− OVEX rats (subsequent experiment) were exposed to a 5 min infusion of 20%CO2 normoxic gas while measuring TST. Menopausal women were given brief 20% and 35%CO2 challenges, and hot flashes were self-reported and objectively verified. Results Compared to controls, OVEX rats had exacerbated increases in TST, and SERT+/− OVEX rats had prolonged TST increases following CO2. Most women reported mild/moderate hot flashes after CO2 challenges, and the hot flash severity to CO2 was positively correlated with daily hot flash frequency. Conclusions The studies demonstrate that this anxiogenic stimulus is capable of inducing cutaneous vasomotor responses in OVEX rats, and eliciting hot flashes in menopausal women. In rats, the severity of the response was mediated by loss of ovarian function and increased anxiety traits (SERT+/−), and, in women, by daily hot flash frequency. These findings may provide insights into anxiety related triggers and genetic risk factors for hot flashes in thermoneutral environments. PMID:27465717

Muzzle flash issues related to the Waco FLIR analysis

NASA Astrophysics Data System (ADS)

Grant, Barbara G.; Hardy, David T.

2001-09-01

The controversy surrounding the origin of flashes on the Mt. Carmel FLIR videotape acquired on April 19, 1993, is introduced. The characteristics of muzzle flash are reviewed. A comparative weapons description is offered. The temporal, spatial, and radiance characteristics of thermal infrared muzzle flash are addressed. Data acquired from a field experiment are presented. The authors conclude that the spatial characteristics of muzzle flash enable its detection by equipment such as the FLIR in use at Mt. Carmel on April 19, 1993; that while flashes obtained in the field appear highly radiant, measurements are necessary to quantify their values; and that the temporal behavior of muzzle flash deserves further study.

The electroluminescence of Xe-Ne gas mixtures: A Monte Carol simulation study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Santos, F.P.; Dias, T.H.V.T.; Rachinhas, P.J.B.M.

1998-04-01

The authors have performed a Monte Carlo simulation of the drift of electrons through a mixture of gaseous xenon with the lighter noble gas neon at a total pressure of 1 atm. The electroluminescence characteristics and other transport parameters are investigated as a function of the reduced electric field and composition of the mixture. For Xe-Ne mixtures with 5, 10, 20, 40, 70, 90, and 100% of Xe, they present results for electroluminescence yield and excitation efficiency, average electron energy, electron drift velocity, reduced mobility, reduced diffusion coefficients, and characteristic energies over a range of reduced electric fields which excludemore » electron multiplication. For the 5% Xe mixture, they also assess the influence of electron multiplication on the electroluminescence yield. The present study of Xe-Ne mixtures was motivated by an interest in using them as a filling for gas proportional scintillation counters in low-energy X-ray applications. In this energy range, the X rays will penetrate further into the detector due to the presence of Ne, and this will lead to an improvement in the collection of primary electrons originating near the detector window and may represent an advantage over the use of pure Xe.« less

Flash LIDAR Systems for Planetary Exploration

NASA Astrophysics Data System (ADS)

Dissly, Richard; Weinberg, J.; Weimer, C.; Craig, R.; Earhart, P.; Miller, K.

2009-01-01

Ball Aerospace offers a mature, highly capable 3D flash-imaging LIDAR system for planetary exploration. Multi mission applications include orbital, standoff and surface terrain mapping, long distance and rapid close-in ranging, descent and surface navigation and rendezvous and docking. Our flash LIDAR is an optical, time-of-flight, topographic imaging system, leveraging innovations in focal plane arrays, readout integrated circuit real time processing, and compact and efficient pulsed laser sources. Due to its modular design, it can be easily tailored to satisfy a wide range of mission requirements. Flash LIDAR offers several distinct advantages over traditional scanning systems. The entire scene within the sensor's field of view is imaged with a single laser flash. This directly produces an image with each pixel already correlated in time, making the sensor resistant to the relative motion of a target subject. Additionally, images may be produced at rates much faster than are possible with a scanning system. And because the system captures a new complete image with each flash, optical glint and clutter are easily filtered and discarded. This allows for imaging under any lighting condition and makes the system virtually insensitive to stray light. Finally, because there are no moving parts, our flash LIDAR system is highly reliable and has a long life expectancy. As an industry leader in laser active sensor system development, Ball Aerospace has been working for more than four years to mature flash LIDAR systems for space applications, and is now under contract to provide the Vision Navigation System for NASA's Orion spacecraft. Our system uses heritage optics and electronics from our star tracker products, and space qualified lasers similar to those used in our CALIPSO LIDAR, which has been in continuous operation since 2006, providing more than 1.3 billion laser pulses to date.

Organic flash cycles for efficient power production

DOEpatents

Ho, Tony; Mao, Samuel S.; Greif, Ralph

2016-03-15

This disclosure provides systems, methods, and apparatus related to an Organic Flash Cycle (OFC). In one aspect, a modified OFC system includes a pump, a heat exchanger, a flash evaporator, a high pressure turbine, a throttling valve, a mixer, a low pressure turbine, and a condenser. The heat exchanger is coupled to an outlet of the pump. The flash evaporator is coupled to an outlet of the heat exchanger. The high pressure turbine is coupled to a vapor outlet of the flash evaporator. The throttling valve is coupled to a liquid outlet of the flash evaporator. The mixer is coupled to an outlet of the throttling valve and to an outlet of the high pressure turbine. The low pressure turbine is coupled to an outlet of the mixer. The condenser is coupled to an outlet of the low pressure turbine and to an inlet of the pump.

Hot flashes in breast cancer survivors: Frequency, severity and impact.

PubMed

Chang, Hao-Yuan; Jotwani, Aparna C; Lai, Yeur-Hur; Jensen, Mark P; Syrjala, Karen L; Fann, Jesse R; Gralow, Julie

2016-06-01

To (1) determine the frequency and severity of hot flashes, (2) examine the associations between hot flash frequency and severity and quality of life, and (3) identify the predictors of hot flash activity in breast cancer survivors. The study used a cross-sectional design and mailed survey of 253 breast cancer survivors recruited from a cancer wellness clinic. Participants provided information regarding cancer history, hot flashes, pain intensity, sleep problems, physical functioning, and psychological functioning. About half of the survivors reported at least one hot flash in the past 24 h (45%) or past week (52%). The average frequency of hot flashes was 1.9 in the past 24 h and 1.8 in the past week. Hot flash severity was usually mild or asymptomatic. However, participants with hot flashes reported significantly more sleep problems and higher pain severity than those reporting no hot flashes. Moreover, the severity of hot flashes was associated with more sleep problems, higher pain severity, and more psychological dysfunction. History of hormonal suppression therapy and younger age predicted hot flash activity in the study sample. In breast cancer survivors, hot flashes are common and are associated with unpleasant symptoms and poor quality of life. Research is needed to determine if treatments that reduce the frequency and severity of hot flashes in breast cancer survivors also result in improvements in symptoms such as sleep problems, pain, and psychological dysfunction. Copyright © 2016 Elsevier Ltd. All rights reserved.