A VUV photoionization measurement and ab-initio calculation of the ionization energy of gas phase SiO2

Energy Technology Data Exchange (ETDEWEB)

Kostko, Oleg; Ahmed, Musahid; Metz, Ricardo B.

2008-12-05

In this work we report on the detection and vacuum-ultraviolet (VUV) photoionization of gas phase SiO2 generated in situ via laser ablation of silicon in a CO2 molecular beam. The resulting species are investigated by single photon ionization with tunable VUV synchrotron radiation and mass analyzed using reflectron mass spectrometry. Photoionization efficiency (PIE) curves are recorded for SiO and SiO2 and ionization energy estimates are revealed from such measurements. A state-to-state ionizationenergy of 12.60 (+-0.05) eV is recorded by fitting two prominent peaks in the PIE curve for the following process: 1SUM O-Si-O --> 2PRODg [O-Si-O]+. Electronic structure calculations aid in the interpretation of the photoionization process and allow for identification of the symmetric stretch of 2PRODg [O-Si-O]+ which is observed in the PIE spectrum to be 0.11 eV (890 cm-1) above the ground state of the cation and agrees with the 892 cm-1 symmetric stretch frequency calculated at the CCSD(T)/aug-cc-pVTZ level.

Experience with the UHV box coater and the evaporation procedure for VUV reflective coatings on the HADES RICH mirror

CERN Document Server

Maier-Komor, P; Wieser, J; Ulrich, A

1999-01-01

An UHV box coater was set up for the deposition of highly reflective layers in the vacuum ultraviolet (VUV) wavelength range on large-area mirror substrates. The VUV mirrors are needed for the ring imaging Cherenkov (RICH) detector of the high-acceptance di-electron spectrometer (HADES). The complete dry vacuum system is described. The spatial deposition distribution from the evaporation sources was measured. The reflectivity of the Al mirror layer was optimized for the wavelength range of 145-210 nm by varying the thickness of the MgF sub 2 protective layer. The setup for measuring the reflectivity in the VUV range is described and reflectivity data are presented.

Update on VUV and soft X-ray facilities at SSRL

International Nuclear Information System (INIS)

Waldhauer, A.

1988-01-01

The number of experimental stations at SSRL devoted to the VUV and soft X-ray region is increasing rapidly. In 1986 there were five VUV/soft X-ray beam lines in regular operation. These consisted of two grasshopper lines, a Seya-Namioka line, a white light lithography line, and the UHV double crystal line, Jumbo. By 1988 ten beam lines, including two with insertion devices, covering the spectral range 5-4000 eV in five overlapping ranges will be operational. With the addition of these new stations, SSRL will have increased dramatically its facilities for performing VUV and soft X-ray research. (orig.)

UV and VUV photolysis vs. UV/H2O2 and VUV/H2O2, treatment for removal of clofibric acid from aqueous solution.

Science.gov (United States)

Li, Wenzhen; Lu, Shuguang; Qiu, Zhaofu; Lin, Kuangfei

2011-07-01

Clofibric acid (CA), a metabolite of lipid regulators, was investigated in ultra-pure water and sewage treatment plant (STP) effluent at 10 degrees C under UV, vacuum UV (VUV), UV/H2O2 and VUV/H2O2 processes. The influences of NO3-, HCO3- and humic acid (HA) on CA photolysis in all processes were examined. The results showed that all the experimental data well fitted the pseudo-first-order kinetic model, and the apparent rate constant (k(ap)) and half-life time (t(1/2)) were calculated accordingly. Direct photolysis of CA through UV irradiation was the main process, compared with the indirect oxidation of CA due to the slight generation of hydroxyl radicals dissociated from water molecules under UV irradiation below 200 nm monochromatic wavelength emission. In contrast, indirect oxidation was the main CA degradation mechanism in UV/H2O2 and VUV/H2O2, and VUV/H2O2 was the most effective process for CA degradation. The addition of 20 mg L(-1) HA could significantly inhibit CA degradation, whereas, except for UV irradiation, the inhibitive effects of NO3- and HCO3- (1.0 x 10(-3) and 0.1 mol L(-1), respectively) on CA degradation were observed in all processes, and their adverse effects were more significant in UV/H2O2 and VUV/H2O2 processes, particularly at the high NO3- and HCO3- concentrations. The degradation rate decreased 1.8-4.9-fold when these processes were applied to a real STP effluent owing to the presence of complex constituents. Of the four processes, VUV/H2O2 was the most effective, and the CA removal efficiency reached over 99% after 40 min in contrast to 80 min in both the UV/H2O2 and VUV processes and 240 min in the UV process.

Characteristics and performance of the Los Alamos VUV beamline at the NSLS

International Nuclear Information System (INIS)

Bartlett, R.J.; Trela, W.J.; Michaud, F.D.; Southworth, S.H.; Alkire, R.W.; Roy, P.; Rothe, R.; Walsh, P.J.; Shinn, N.

1988-01-01

We describe the design and performance of the Los Alamos VUV synchrotron radiation beamline, U3C, on the VUV ring of the National Synchrotron Light Source at Brookhaven National Laboratory. The beamline uses separate function optics to collect and focus the horizontally and vertically diverging beam. The monochromator is a grazing incidence Rowland circle instrument of the extended grasshopper design (ERG). A postmonochromator refocusing mirror is used to focus or collimate the diverging beam from the monochromator. The beamline control and diagnostics systems are also discussed. Particular emphasis in the design has been placed on the reduction of stray and harmonic light. Higher order light is reduced by a grazing angle mirror low pass filter installed immediately downstream from the monochromator while stray light is reduced through the use of baffles and thin film filters. Also included in the line is a differential pumping section that permits gas phase and other experiments requiring pressures in the 10 -5 to 10 -4 Torr range to be coupled to the beamline. (orig.)

VUV/XUV measurements of impurity emission in plasmas with liquid lithium surfaces on LTX

International Nuclear Information System (INIS)

Tritz, Kevin; Finkenthal, Michael; Stutman, Dan; Bell, Ronald E; Boyle, Dennis; Kaita, Robert; Kozub, Tom; Lucia, Matthew; Majeski, Richard; Merino, Enrique; Schmitt, John; Beiersdorfer, Peter; Clementson, Joel; Kubota, Shigeyuki

2014-01-01

The VUV/XUV spectrum has been measured on the Lithium Tokamak eXperiment (LTX) using a transmission grating imaging spectrometer (TGIS) coupled to a direct-detection x-ray charge-coupled device camera. TGIS data show significant changes in the ratios between the lithium and oxygen impurity line emission during discharges with varying lithium wall conditions. Lithium coatings that have been passivated by lengthy exposure to significant levels of impurities contribute to a large O/Li ratio measured during LTX plasma discharges. Furthermore, previous results have indicated that a passivated lithium film on the plasma facing components will function as a stronger impurity source when in the form of a hot liquid layer compared to a solid lithium layer. However, recent TGIS measurements of plasma discharges in LTX with hot stainless steel boundary shells and a fresh liquid lithium coating show lower O/Li impurity line ratios when compared to discharges with a solid lithium film on cool shells. These new measurements help elucidate the somewhat contradictory results of the effects of solid and liquid lithium on plasma confinement observed in previous experiments. (paper)

User oriented end-station on VUV pump-probe magneto-optical ellipsometry at ELI beamlines

Science.gov (United States)

Espinoza, Shirly; Neuber, Gerd; Brooks, Christopher D.; Besner, Bastian; Hashemi, Maryam; Rübhausen, Michael; Andreasson, Jakob

2017-11-01

A state of the art ellipsometer for user operations is being implemented at ELI Beamlines in Prague, Czech Republic. It combines three of the most promising and exotic forms of ellipsometry: VUV, pump-probe and magneto-optical ellipsometry. This new ellipsometer covers a spectral operational range from the NIR up to the VUV, with high through-put between 1 and 40 eV. The ellipsometer also allows measurements of magneto-optical spectra with a 1 kHz switchable magnetic field of up to 1.5 T across the sample combining ellipsometry and Kerr spectroscopy measurements in an unprecedented spectral range. This form of generalized ellipsometry enables users to address diagonal and off-diagonal components of the dielectric tensor within one measurement. Pump-probe measurements enable users to study the dynamic behaviour of the dielectric tensor in order to resolve the time-domain phenomena in the femto to 100 ns range.

A study of enhanced performance of VUV/UV process for the degradation of micropollutants from contaminated water

Energy Technology Data Exchange (ETDEWEB)

Bagheri, Mehdi; Mohseni, Madjid, E-mail: madjid.mohseni@ubc.ca

2015-08-30

Highlights: • Developing a comprehensive CFD simulation tool for VUV/UV photoreactors modeling. • Analysing impact of reactor hydrodynamics on the AOP performance of VUV/UV process. • Cutting the energy cost of VUV/UV process by means of improved-photoreactor design. • Experimentally verifying the CFD results using a VUV/UV prototype photoreactor. - Abstract: VUV/UV is a chemical-free and straightforward solution for the degradation of emerging contaminants from water sources. The objective of this work was to investigate the feasibility of VUV/UV advanced oxidation process for the effective degradation of a target micropollutant, atrazine, under continuous flow operation of 0.5–6.5 L/min. To provide an in-depth understanding of process, a comprehensive computational fluid dynamics (CFD) model, incorporating flow hydrodynamics, 185 nm VUV and 254 nm UV radiation propagation along with a complete kinetic scheme, was developed and validated experimentally. The experimental degradation rates and CFD predicted values showed great consistency with less than 2.9% average absolute relative deviation (AARD). Utilizing the verified model, energy-efficiency of the VUV/UV process under a wide range of reactor configurations was assessed in terms of electrical energy-per-order (EEO), ·OH concentration as well as delivered UV and VUV dose distributions. Thereby, the extent of mixing and circulation zones was found as key parameter controlling the treatment economy and energy-efficiency of the VUV/UV process. Utilizing a CFD-driven baffle design strategy, an improved VUV/UV process with up to 72% reduction in the total electrical energy requirement of atrazine degradation was introduced and verified experimentally.

Experimental study of carbon materials behavior under high temperature and VUV radiation: Application to Solar Probe+ heat shield

International Nuclear Information System (INIS)

Eck, J.; Sans, J.-L.; Balat-Pichelin, M.

2011-01-01

The aim of the Solar Probe Plus (SP+) mission is to understand how the solar corona is heated and how the solar wind is accelerated. To achieve these goals, in situ measurements are necessary and the spacecraft has to approach the Sun as close as 9.5 solar radii. This trajectory induces extreme environmental conditions such as high temperatures and intense Vacuum Ultraviolet radiation (VUV). To protect the measurement and communication instruments, a heat shield constituted of a carbon material is placed on the top of the probe. In this study, the physical and chemical behavior of carbon materials is experimentally investigated under high temperatures (1600-2100 K), high vacuum (10 -4 Pa) and VUV radiation in conditions near those at perihelion for SP+. Thanks to several in situ and ex situ characterizations, it was found that VUV radiation induced modification of outgassing and of mass loss rate together with alteration of microstructure and morphology.

VUV optical ring resonator for Duke storage ring free electron laser

Energy Technology Data Exchange (ETDEWEB)

Park, S.H.; Litvinenko, V.N.; Madey, J.M.J. [Duke Univ., Durham, NC (United States)] [and others

1995-12-31

The conceptual design of the multifaceted-mirror ring resonator for Duke storage ring VUV FEL is presented. The expected performance of the OK-4 FEL with ring resonator is described. We discuss in this paper our plans to study reflectivity of VUV mirrors and their resistivity to soft X-ray spontaneous radiation from OK-4 undulator.

Design and implementation of VUV-CD and LD measurements using an ac modulated polarizing undulator

International Nuclear Information System (INIS)

Yagi-Watanabe, K.; Yamada, T.; Tanaka, M.; Kaneko, F.; Kitada, T.; Ohta, Y.; Nakagawa, K.

2005-01-01

VUV circular dichroism (CD) and linear dichroism (LD) have been successfully measured at wavelengths beyond the conventional limit by using an ac modulated polarizing undulator. We have developed CD and LD measuring technique by polarization modulation at the source, without using transmission type polarizing modulator, to extend to the coverage to wavelengths shorter than 140-bar nm. AIST developed in 1986 ac polarizing undulator by using a electron storage ring 'TERAS' based on an original concept. The undulator which can produce any desired polarization of vertical- and horizontal-linear polarization (VLP and HLP) and right- and left-handed circular polarization (RCP and LCP) is specially well suited to both measurements of CD and LD. With this undulator, the polarization alternate in the order of VLP-RCP-HLP-RCP-VLP-LCP-HLP-LCP-VLP-, i.e. when circular polarization is modulated in f Hz, linear polarization alters in 2f Hz. This allows us simultaneous measurements of CD and LD. Since the TERAS can produce ac-modulated polarized radiation of wavelength as short as 40-bar nm, it is expected to have CD and LD measurement extended to 40-bar nm

A VUV photoionization organic aerosol mass spectrometric study with synchrotron radiation

Energy Technology Data Exchange (ETDEWEB)

Fang Wenzheng; Lei Gong; Shan Xiaobin; Liu Fuyi [School of Nuclear Science and Technology, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Anhui, Hefei 230029 (China); Wang Zhenya [Laboratory of Environmental Spectroscopy, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031 (China); Sheng Liusi, E-mail: lssheng@ustc.edu.cn [School of Nuclear Science and Technology, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Anhui, Hefei 230029 (China)

2011-04-15

Research highlights: {yields} A photoionization aerosol time-of-flight mass spectrometer (ATOFMS) has been developed for on-line analysis of organic compounds in aerosol particles using tunable vacuum ultraviolet (VUV) synchrotron radiation. {yields} The degree of fragmentation of molecule can be controlled either by the heater temperature or by the photon energy. {yields} The direct determination of the IEs of benzopheneone (9.07 eV), salicylic acid (8.72 eV), and urea (9.85 eV) are measured from the photoionization efficiency spectra. {yields} The species can be identified by their molecular and fragment ions weights as well as by the comparisions between their theoretical and experimental ionization energies. - Abstract: A photoionization aerosol time-of-flight mass spectrometer (ATOFMS) has been developed for on-line analysis of organic compounds in aerosol particles using tunable vacuum ultraviolet (VUV) synchrotron radiation. Aerosol particles can be sampled directly from atmospheric pressure and are focused through an aerodynamic lens assembly into the mass spectrometer. The particles are vaporized when they impact on a heater, and then the nascent vapor is softly photoionized by synchrotron radiation. The degree of fragmentation of molecule can be controlled either by the heater temperature or by the photon energy. Thus, fragment-free tunable VUV mass spectra are obtained by tuning the photon energy close to the ionization energies (IEs) of the sample molecules. The direct determination of the IEs of benzophenone (9.07 eV), salicylic acid (8.72 eV), and urea (9.85 eV) are measured from the photoionization efficiency spectra with uncertainties of {+-}50 meV. Ab initio calculations have been employed to predict the theoretical ionization energy.

Low-k films modification under EUV and VUV radiation

International Nuclear Information System (INIS)

Rakhimova, T V; Rakhimov, A T; Mankelevich, Yu A; Lopaev, D V; Kovalev, A S; Vasil'eva, A N; Zyryanov, S M; Kurchikov, K; Proshina, O V; Voloshin, D G; Novikova, N N; Krishtab, M B; Baklanov, M R

2014-01-01

Modification of ultra-low-k films by extreme ultraviolet (EUV) and vacuum ultraviolet (VUV) emission with 13.5, 58.4, 106, 147 and 193 nm wavelengths and fluences up to 6 × 10 18  photons cm −2 is studied experimentally and theoretically to reveal the damage mechanism and the most ‘damaging’ spectral region. Organosilicate glass (OSG) and organic low-k films with k-values of 1.8–2.5 and porosity of 24–51% are used in these experiments. The Si–CH 3 bonds depletion is used as a criterion of VUV damage of OSG low-k films. It is shown that the low-k damage is described by two fundamental parameters: photoabsorption (PA) cross-section σ PA and effective quantum yield φ of Si–CH 3 photodissociation. The obtained σ PA and φ values demonstrate that the effect of wavelength is defined by light absorption spectra, which in OSG materials is similar to fused silica. This is the reason why VUV light in the range of ∼58–106 nm having the highest PA cross-sections causes strong Si–CH 3 depletion only in the top part of the films (∼50–100 nm). The deepest damage is observed after exposure to 147 nm VUV light since this emission is located at the edge of Si–O absorption, has the smallest PA cross-section and provides extensive Si–CH 3 depletion over the whole film thickness. The effective quantum yield slowly increases with the increasing porosity but starts to grow quickly when the porosity exceeds the critical threshold located close to a porosity of ∼50%. The high degree of pore interconnectivity of these films allows easy movement of the detached methyl radicals. The obtained results have a fundamental character and can be used for prediction of ULK material damage under VUV light with different wavelengths. (paper)

National synchrotron light source user's manual: Guide to the VUV and x-ray beamlines: Third edition

International Nuclear Information System (INIS)

Gmuer, N.F.; Thomlinson, W.; White-DePace, S.

1989-01-01

This report contains information on the following topics: A Word on the Writing of Beamline Descriptions; Beamline Equipment Utilization for General Users; the Vacuum Ultraviolet (VUV) Storage Ring and Beamlines; VUV Beamline Descriptions--An Explanation; VUV Beamline Descriptions; X-Ray Storage Ring and Beamlines; X-Ray Beamline Descriptions--An Explanation; and X-Ray Beamline Descriptions

Characterization of Vacuum Ultraviolet (VUV) Radiation for the Development of a Fluorescent Lamp

International Nuclear Information System (INIS)

Khatun, Hasina; Sharma, A. K.; Barhai, P. K.

2011-01-01

A negative unipolar pulsed voltage is applied to study internal electrical parameters of the xenon filled dielectric barrier discharge (DBD) sources. The VUV radiation emitted from these sources is characterized by means of the photoluminescence intensity of the red phosphor pellet. The red phosphor converts the VUV radiation into visible radiation and the emission spectra include a peak at 619.56 nm. The emission characteristics of the red phosphor are analyzed in terms of the pressure-distance (pd), rise time and frequency of the pulsed voltage waveform. The emission intensity measured at different operational conditions confirms that the formation and decay of the xenon excimer, Xe 2 *, increase with the increase in reduced electric field, E/N. After exceeding certain limits of E/N, the intensity of Xe 2 * decreases rapidly. (plasma technology)

New perspectives for organic chemistry and biochemistry in VUV: reaction kinetics, chirality and thermochemistry. Summaries

International Nuclear Information System (INIS)

Nahon, Laurent; Field, David; Gerber, Thomas; Knopp, Gregor; Beaud, Paul; Radi, Peter; Tulej, Marek; Dedonder-Lardeux, Claude; Jung, J.M.; Laprevote, Olivier; Thissen, Roland; Le Barbu, K.; Lahmani, F.; Zehnacker, A.; Maurizot, Jean Claude; Barbier, Bernard; Kagan, Henri B.

2001-10-01

The aim of this workshop was to examine the conditions of use of VUV for the study of complex molecular systems, and notably bio-molecules, a domain which is greatly expanding. The conclusions of this one-day workshop should allow to define new fields of utilization of the synchrotron radiation in VUV, to precise certain performances that are needed for the transferred line, to establish the complementarities with other VUV sources (lasers, free electron lasers, lamps) and to determine the eventual need for a second low energy light line at SOLEIL. The titles of the various abstract papers presented are (two papers are in English, the rest is in French): SU5, a high resolution and variable polarization VUV line that should be transferred at SOLEIL; Interstellar organic chemistry (in English); Application of spectroscopic techniques in the VUV to combustion relevant molecules (in English); Gaseous phase reaction kinetics (bi-molecular reactions in collision and in aggregates); Liquids of biological interest (excitation and relaxation close to the ionization threshold); Successes and impediments in protein mass spectrometry (the potential contribution of VUV synchrotron radiation); Stereo-specific effects; Complexes between chiral molecules; circular dichroism of biomolecules; Exobiology; asymmetric synthesis (principles and recent results)

The VUV instrument SPICE for Solar Orbiter: performance ground testing

Science.gov (United States)

Caldwell, Martin E.; Morris, Nigel; Griffin, Douglas K.; Eccleston, Paul; Anderson, Mark; Pastor Santos, Carmen; Bruzzi, Davide; Tustain, Samuel; Howe, Chris; Davenne, Jenny; Grundy, Timothy; Speight, Roisin; Sidher, Sunil D.; Giunta, Alessandra; Fludra, Andrzej; Philippon, Anne; Auchere, Frederic; Hassler, Don; Davila, Joseph M.; Thompson, William T.; Schuehle, Udo H.; Meining, Stefan; Walls, Buddy; Phelan, P.; Dunn, Greg; Klein, Roman M.; Reichel, Thomas; Gyo, Manfred; Munro, Grant J.; Holmes, William; Doyle, Peter

2017-08-01

SPICE is an imaging spectrometer operating at vacuum ultraviolet (VUV) wavelengths, 70.4 - 79.0 nm and 97.3 - 104.9 nm. It is a facility instrument on the Solar Orbiter mission, which carries 10 science instruments in all, to make observations of the Sun's atmosphere and heliosphere, at close proximity to the Sun, i.e to 0.28 A.U. at perihelion. SPICE's role is to make VUV measurements of plasma in the solar atmosphere. SPICE is designed to achieve spectral imaging at spectral resolution >1500, spatial resolution of several arcsec, and two-dimensional FOV of 11 x16arcmins. The many strong constraints on the instrument design imposed by the mission requirements prevent the imaging performance from exceeding those of previous instruments, but by being closer to the sun there is a gain in spatial resolution. The price which is paid is the harsher environment, particularly thermal. This leads to some novel features in the design, which needed to be proven by ground test programs. These include a dichroic solar-transmitting primary mirror to dump the solar heat, a high in-flight temperature (60deg.C) and gradients in the optics box, and a bespoke variable-line-spacing grating to minimise the number of reflective components used. The tests culminate in the systemlevel test of VUV imaging performance and pointing stability. We will describe how our dedicated facility with heritage from previous solar instruments, is used to make these tests, and show the results, firstly on the Engineering Model of the optics unit, and more recently on the Flight Model. For the keywords, select up to 8 key terms for a search on your manuscript's subject.

Gas-filled cell as a narrow bandwidth bandpass filter in the VUV wavelength range

Energy Technology Data Exchange (ETDEWEB)

Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2011-04-15

We propose a method for spectrally filtering radiation in the VUV wavelength range by means of a monochromator constituted by a cell filled with a resonantly absorbing rare gas. Around particular wavelengths, the gas exhibits narrow-bandwidth absorbing resonances following the Fano profile. In particular, within the photon energy range 60 eV-65 eV, the correlation index of the Fano profiles for the photoionization spectra in Helium is equal to unity, meaning that the minimum of the cross-section is exactly zero. For sufficiently large column density in the gas cell, the spectrum of the incoming radiation will be attenuated by the background cross-section of many orders of magnitude, except for those wavelengths close to the point where the cross-section is zero. Remarkable advantages of a gas monochromator based on this principle are simplicity, efficiency and narrow-bandwidth. A gas monochromator installed in the experimental hall of a VUV SASE FEL facility would enable the delivery of a single-mode VUV laser beam. The design is identical to that of already existing gas attenuator systems for VUV or X-ray FELs. We present feasibility study and exemplifications for the FLASH facility in the VUV regime. (orig.)

Photodissociation of Small Molecules and Photoionization of Free Radicals Using the VUV Velocity-Map Imaging Photoion and Photoelectron Method

Science.gov (United States)

Gao, Hong

The tunable vacuum ultraviolet (VUV) laser generated through the two-photon resonance-enhanced four-wave mixing scheme is combined with the newly developed time-slice velocity map imaging photoion method to study the photodissociation of small molecules in the VUV region, and with the velocity map imaging photoelectron method to study the photoionization of free radicals. The photodissociation dynamics of NO in the energy region around 13.5 eV has been investigated. Branching ratios of the three lowest dissociation channels of 12C 16O that produce C(3P) + O(3P), C( 1D) + O(3P) and C(3P) + O(1D) are measured for the first time in the VUV region from 102,500 cm-1 to 110,500 cm-1, valuable information of the dissociation dynamics for this prototype system has been deduced. We demonstrated an experiment that has two independently tunable VUV lasers and a time-slice velocity map imaging setup, this provides us a global way to perform systematic state-selected photodissociation of small molecules via state-selected detection of the atomic products in the VUV region. The velocity map imaging photoelectron method was successfully used to obtain the photoelectron spectrum of the propargyl radical (C3H3) via a single VUV photoionization process. The propargyl radical is generated by the 193 nm laser photodissociation of the precursor C3H3Cl. This is the first time that the velocity map imaging photoelectron method is used to get the photoelectron spectra of free radicals, indicating that it is a powerful technique for studying the photoionization of free radicals which are always hard to be produced with high enough number densities for spectroscopic studies. This dissertation is mainly based on the following peer-reviewed journal articles: 1. Hong Gao, Yang Pan, Lei Yang, Jingang Zhou, C. Y. Ng and William M. Jackson. "Time-slice velocity-map ion imaging studies of the Photodissociation of NO in the vacuum ultraviolet region", the Journal of Chemical Physics, 136, 134302

An XUV/VUV free-electron laser oscillator

Science.gov (United States)

Goldstein, J. C.; Newnam, B. E.; Cooper, R. K.; Comly, J. C., Jr.

Problems regarding the extension of free-electron laser technology from the visible and near infrared region, where such devices are currently operating, to the ultraviolet have recently been extensively discussed. It was found that significant technical problems must be overcome before free-electron lasers (FELs) can be operated in the VUV (100-200 nm) and the XUV (50-100). However, the present lack of other intense and tunable sources of coherent radiation at these wavelengths together with the intrinsic properties of FELs make the development of such devices potentially very rewarding. The properties of FELs include continuous tunability in wavelength and output in the form of a train of picosecond pulses. An investigation is conducted regarding the feasibility of an operation of a FEL in the XUV/VUV regions, taking into account a theoretical model. It is found that modest improvements in electron beam and optical mirror technologies will make the design of a FEL for operation in the 50-200-nm range of optical wavelength possible.

VUV light induced valence degeneration in Sm over-layer on HOPG

International Nuclear Information System (INIS)

Kutluk, G; Nakatake, M; Arita, M; Namatame, H; Taniguchi, M; Ishitobi, Y; Sumida, H

2013-01-01

Systematic investigation of the influence of vacuum ultraviolet (VUV) irradiation on the valence degeneration in a Sm over-layer on a HOPG substrate was performed using in-situ photoemission spectroscopy (XPS, UPS, and ARPES) for the Sm coverage regime of 0.05-3.6 Å. This investigation confirmed that VUV irradiation-induced degeneration of divalent Sm exerts a more profound effect than Sm contamination during photoemission spectroscopy even under UHV. We found that the charge transfer occurs mainly from divalent Sm to the HOPG surface.

Photoluminescence of phosphors for PDP with VUV excitation

International Nuclear Information System (INIS)

Lu, H.-C.; Chen, H.-K.; Tseng, T.-Y.; Kuo, W.-L.; Alam, M.S.; Cheng, B.-M.

2005-01-01

In a plasma display panel (PDP) He-Xe or Ne-Xe gaseous mixtures are subjected to electric discharge between two glass panels, so to generate VUV light. Red, green and blue phosphors absorb this VUV radiation and re-radiate the energy as visible light to produce the colors that appear on the screen. The phosphor plays an important role in the working of a PDP. To improve the efficiency of phosphors, we have established a photoluminescence end station coupled to the beam line of a synchrotron to study the luminescence of PDP phosphors. This luminescence is analyzed with a 0.32 m monochromator having maximum resolution 0.04 nm, and is monitored with a photomultiplier tube operated in a photon-counting mode. Preliminary data demonstrate the powerful performance of this end-station for studying PDP phosphors

UV-VUV laser induced phenomena in SiO2 glass

International Nuclear Information System (INIS)

Kajihara, Koichi; Ikuta, Yoshiaki; Oto, Masanori; Hirano, Masahiro; Skuja, Linards; Hosono, Hideo

2004-01-01

Creation and annihilation of point defects were studied for SiO 2 glass exposed to ultraviolet (UV) and vacuum UV (VUV) lights to improve transparency and radiation toughness of SiO 2 glass to UV-VUV laser light. Topologically disordered structure of SiO 2 glass featured by the distribution of Si-O-Si angle is a critical factor degrading transmittance near the fundamental absorption edge. Doping with terminal functional groups enhances the structural relaxation and reduces the number of strained Si-O-Si bonds by breaking up the glass network without creating the color centers. Transmittance and laser toughness of SiO 2 glass for F 2 laser is greatly improved in fluorine-doped SiO 2 glass, often referred as 'modified silica glass'. Interstitial hydrogenous species are mobile and reactive at ambient temperature, and play an important role in photochemical reactions induced by exposure to UV-VUV laser light. They terminate the dangling-bond type color centers, while enhancing the formation of the oxygen vacancies. These findings are utilized to develop a deep-UV optical fiber transmitting ArF laser photons with low radiation damage

VUV photoionization of acetamide studied by electron/ion coincidence spectroscopy in the 8–24 eV photon energy range

International Nuclear Information System (INIS)

Schwell, Martin; Bénilan, Yves; Fray, Nicolas; Gazeau, Marie-Claire; Es-Sebbar, Et.; Garcia, Gustavo A.; Nahon, Laurent; Champion, Norbert; Leach, Sydney

2012-01-01

Highlights: ► We study the VUV photoionization of acetamide in the 8–24 eV photon energy range. ► Electron/ion coincidence measurements are performed using synchrotron radiation. ► The adiabatic ionization energy of acetamide is determined by TPEPICO measurements. ► VUV induced fragmentation pathways of acetamide are assigned and discussed. - Abstract: A VUV photoionization study of acetamide was carried out over the 8–24 eV photon energy range using synchrotron radiation and photoelectron/photoion coincidence (PEPICO) spectroscopy. Threshold photoelectron photoion coincidence (TPEPICO) measurements were also made. Photoion yield curves and branching ratios were measured for the parent ion and six fragment ions. The adiabatic ionization energy of acetamide was determined as I.E. (1 2 A′) = (9.71 ± 0.02) eV, in agreement with an earlier reported photoionization mass spectrometry (PIMS) value. The adiabatic energy of the first excited state of the ion, 1 2 A″, was determined to be ≈10.1 eV. Assignments of the fragment ions and the pathways of their formation by dissociative photoionization were made. The neutral species lost in the principal dissociative photoionization processes are CH 3 , NH 2 , NH 3 , CO, HCCO and NH 2 CO. Heats of formation are derived for all ions detected and are compared with literature values. Some astrophysical implications of these results are discussed.

Experimental study of pyrolytic boron nitride at high temperature with and without proton and VUV irradiations

International Nuclear Information System (INIS)

Balat-Pichelin, M.; Eck, J.; Heurtault, S.; Glénat, H.

2014-01-01

Highlights: • New results for the high temperature study of pBN in high vacuum for the heat shield of solar probes. • Physico-chemical behavior of pBN studied up to 1700 K with proton and VUV irradiations. • Rather low effect of synergistic aggressions on the microstructure of pBN material. • The α/ε ratio of pBN coating on C/C measured up to 2200 K is 20% lower than for the C/C itself. - Abstract: In the frame of future exploration missions such as Solar Probe Plus (NASA) and PHOIBOS (ESA), research was carried out to study pyrolytic BN material envisaged as coating for their heat shields. The physico-chemical behavior of CVD pBN at very high temperature with or without hydrogen ions and VUV (Vacuum Ultra-Violet) irradiations was studied in high vacuum together with the in situ measurement of the thermal radiative properties conditioning the thermal equilibrium of the heat shield. Experimental results obtained on massive pBN samples are presented through in situ mass spectrometry and mass loss rate, and post-test microstructural characterization by XRD, SEM, AFM and nano-indentation techniques, some of them leading to mechanical properties. It could be concluded that synergistic effect of high temperature, protons and VUV radiation has an impact on the emission of gaseous species, the mass loss rate and the mechanical properties of the material

A straightforward method for Vacuum-Ultraviolet flux measurements: The case of the hydrogen discharge lamp and implications for solid-phase actinometry

International Nuclear Information System (INIS)

Fulvio, D.; Brieva, A. C.; Jäger, C.; Cuylle, S. H.; Linnartz, H.; Henning, T.

2014-01-01

Vacuum-Ultraviolet (VUV) radiation is responsible for the photo-processing of simple and complex molecules in several terrestrial and extraterrestrial environments. In the laboratory such radiation is commonly simulated by inexpensive and easy-to-use microwave-powered hydrogen discharge lamps. However, VUV flux measurements are not trivial and the methods/devices typically used for this purpose, mainly actinometry and calibrated VUV silicon photodiodes, are not very accurate or expensive and lack of general suitability to experimental setups. Here, we present a straightforward method for measuring the VUV photon flux based on the photoelectric effect and using a gold photodetector. This method is easily applicable to most experimental setups, bypasses the major problems of the other methods, and provides reliable flux measurements. As a case study, the method is applied to a microwave-powered hydrogen discharge lamp. In addition, the comparison of these flux measurements to those obtained by O 2 actinometry experiments allow us to estimate the quantum yield (QY) values QY 122  = 0.44 ± 0.16 and QY 160  = 0.87 ± 0.30 for solid-phase O 2 actinometry.

A straightforward method for Vacuum-Ultraviolet flux measurements: The case of the hydrogen discharge lamp and implications for solid-phase actinometry

Energy Technology Data Exchange (ETDEWEB)

Fulvio, D., E-mail: daniele.fulvio@uni-jena.de, E-mail: dfu@oact.inaf.it; Brieva, A. C.; Jäger, C. [Laboratory Astrophysics Group of the Max Planck Institute for Astronomy at the Friedrich Schiller University Jena, Institute of Solid State Physics, Helmholtzweg 3, D-07743 Jena (Germany); Cuylle, S. H.; Linnartz, H. [Raymond and Beverly Sackler Laboratory for Astrophysics, Leiden Observatory, Leiden University, P.O. box 9513, 2300 RA Leiden (Netherlands); Henning, T. [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany)

2014-07-07

Vacuum-Ultraviolet (VUV) radiation is responsible for the photo-processing of simple and complex molecules in several terrestrial and extraterrestrial environments. In the laboratory such radiation is commonly simulated by inexpensive and easy-to-use microwave-powered hydrogen discharge lamps. However, VUV flux measurements are not trivial and the methods/devices typically used for this purpose, mainly actinometry and calibrated VUV silicon photodiodes, are not very accurate or expensive and lack of general suitability to experimental setups. Here, we present a straightforward method for measuring the VUV photon flux based on the photoelectric effect and using a gold photodetector. This method is easily applicable to most experimental setups, bypasses the major problems of the other methods, and provides reliable flux measurements. As a case study, the method is applied to a microwave-powered hydrogen discharge lamp. In addition, the comparison of these flux measurements to those obtained by O{sub 2} actinometry experiments allow us to estimate the quantum yield (QY) values QY{sub 122} = 0.44 ± 0.16 and QY{sub 160} = 0.87 ± 0.30 for solid-phase O{sub 2} actinometry.

Simultaneous nitrate reduction and acetaminophen oxidation using the continuous-flow chemical-less VUV process as an integrated advanced oxidation and reduction process

Energy Technology Data Exchange (ETDEWEB)

Moussavi, Gholamreza, E-mail: moussavi@modares.ac.ir; Shekoohiyan, Sakine

2016-11-15

Highlights: • Simultaneous advanced oxidation and reduction processes were explored in VUV system. • Complete reduction of nitrate to N{sub 2} was achieved at the presence of acetaminophen. • Complete degradation of acetaminophen was achieved at the presence of nitrate. • Over 95% of acetaminophen was mineralized in the VUV photoreactor. • VUV is a chemical-less advanced process for treating water emerging contaminants. - Abstract: This work was aimed at investigating the performance of the continuous-flow VUV photoreactor as a novel chemical-less advanced process for simultaneously oxidizing acetaminophen (ACT) as a model of pharmaceuticals and reducing nitrate in a single reactor. Solution pH was an important parameter affecting the performance of VUV; the highest ACT oxidation and nitrate reduction attained at solution pH between 6 and 8. The ACT was oxidized mainly by HO· while the aqueous electrons were the main working agents in the reduction of nitrate. The performance of VUV photoreactor improved with the increase of hydraulic retention time (HRT); the complete degradation of ACT and ∼99% reduction of nitrate with 100% N{sub 2} selectivity achieved at HRT of 80 min. The VUV effluent concentrations of nitrite and ammonium at HRT of 80 min were below the drinking water standards. The real water sample contaminated with the ACT and nitrate was efficiently treated in the VUV photoreactor. Therefore, the VUV photoreactor is a chemical-less advanced process in which both advanced oxidation and advanced reduction reactions are accomplished. This unique feature possesses VUV photoreactor as a promising method of treating water contaminated with both pharmaceutical and nitrate.

Simultaneous nitrate reduction and acetaminophen oxidation using the continuous-flow chemical-less VUV process as an integrated advanced oxidation and reduction process

International Nuclear Information System (INIS)

Moussavi, Gholamreza; Shekoohiyan, Sakine

2016-01-01

Highlights: • Simultaneous advanced oxidation and reduction processes were explored in VUV system. • Complete reduction of nitrate to N_2 was achieved at the presence of acetaminophen. • Complete degradation of acetaminophen was achieved at the presence of nitrate. • Over 95% of acetaminophen was mineralized in the VUV photoreactor. • VUV is a chemical-less advanced process for treating water emerging contaminants. - Abstract: This work was aimed at investigating the performance of the continuous-flow VUV photoreactor as a novel chemical-less advanced process for simultaneously oxidizing acetaminophen (ACT) as a model of pharmaceuticals and reducing nitrate in a single reactor. Solution pH was an important parameter affecting the performance of VUV; the highest ACT oxidation and nitrate reduction attained at solution pH between 6 and 8. The ACT was oxidized mainly by HO· while the aqueous electrons were the main working agents in the reduction of nitrate. The performance of VUV photoreactor improved with the increase of hydraulic retention time (HRT); the complete degradation of ACT and ∼99% reduction of nitrate with 100% N_2 selectivity achieved at HRT of 80 min. The VUV effluent concentrations of nitrite and ammonium at HRT of 80 min were below the drinking water standards. The real water sample contaminated with the ACT and nitrate was efficiently treated in the VUV photoreactor. Therefore, the VUV photoreactor is a chemical-less advanced process in which both advanced oxidation and advanced reduction reactions are accomplished. This unique feature possesses VUV photoreactor as a promising method of treating water contaminated with both pharmaceutical and nitrate.

Atmospheric pressure photoionization using tunable VUV synchrotron radiation

International Nuclear Information System (INIS)

Giuliani, A.; Giorgetta, J.-L.; Ricaud, J.-P.; Jamme, F.; Rouam, V.; Wien, F.; Laprévote, O.; Réfrégiers, M.

2012-01-01

Highlights: ► Coupling of an atmospheric pressure photoionization source with a vacuum ultra-violet (VUV) beamline. ► The set up allows photoionization up to 20 eV. ► Compared to classical atmospheric pressure photoionization (APPI), our set up offers spectral purity and tunability. ► Allows photoionization mass spectrometry on fragile and hard to vaporize molecules. - Abstract: We report here the first coupling of an atmospheric pressure photoionization (APPI) source with a synchrotron radiation beamline in the vacuum ultra-violet (VUV). A commercial APPI source of a QStar Pulsar i from AB Sciex was modified to receive photons from the DISCO beamline at the SOLEIL synchrotron radiation facility. Photons are delivered at atmospheric pressure in the 4–20 eV range. The advantages of this new set up, termed SR-APPI, over classical APPI are spectral purity and continuous tunability. The technique may also be used to perform tunable photoionization mass spectrometry on fragile compounds difficult to vaporize by classical methods.

VUV Study of Electron-Pyrimidine Dissociative Excitation

Science.gov (United States)

Hein, Jeff; Al-Khazraji, Hajar; Tiessen, Collin; Lukic, Dragan; Trocchi, Joshuah; McConkey, William

2013-05-01

A crossed electron-gas beam system coupled to a VUV spectrometer has been used to investigate the dissociation of pyrimidine (C4H4N2) into excited atomic fragments in the electron-impact energy range from threshold to 375 eV. Data have been made absolute using Lyman- α from H2 as a secondary standard. The main features in the spectrum are the H Lyman series lines. The emission cross section of Lyman- α is measured to be (2.44 +/- 0.25) 10-18 cm2 at 100 eV impact energy. The probability of extracting C or N atoms from the ring is shown to be very small. Possible dissociation channels and excitation mechanisms in the parent molecule will be discussed. The authors thank NSERC (Canada) for financial support.

VUV/UV light inducing accelerated phenol degradation with a low electric input.

Science.gov (United States)

Li, Mengkai; Wen, Dong; Qiang, Zhimin; Kiwi, John

2017-01-23

This study presents the first evidence for the accelerated degradation of phenol by Fenton's reagent in a mini-fluidic VUV/UV photoreaction system (MVPS). A low-pressure mercury lamp used in the MVPS led to a complete degradation of phenol within 4-6 min. The HO˙ and HO 2 ˙ originating from both Fenton's reagent and VUV photolysis of water were identified with suitable radical scavengers. The effects of initial concentrations of phenol, H 2 O 2 and Fe 3+ as well as solution pH on phenol degradation kinetics were examined. Increasing the initial phenol concentration slowed down the phenol degradation, whereas increasing the initial H 2 O 2 or Fe 3+ concentration accelerated the phenol degradation. The optimal solution pH was 3.7. At both 254 and 185 nm, increasing phenol concentration enhanced its absorption for the incident photons. The reaction mechanism for the degradation of phenol was suggested consistent with the results obtained. This study indicates that the VUV/UV photo-Fenton process has potential applications in the treatment of industrial wastewater containing phenol and related aromatic pollutants.

Photochemical decomposition of perfluorooctanoic acid in aqueous periodate with VUV and UV light irradiation

International Nuclear Information System (INIS)

Cao, M.H.; Wang, B.B.; Yu, H.S.; Wang, L.L.; Yuan, S.H.; Chen, J.

2010-01-01

The photochemical decomposition of perfluorooctanoic acid (PFOA) in aqueous periodate (IO 4 - ) was investigated under two types of low-pressure mercury lamps: one emits at 254 nm light (UV light) and the other emits both 254 nm and 185 nm light (VUV light). PFOA decomposed efficiently under VUV light irradiation while it decomposed poorly under UV light irradiation. The addition of IO 4 - significantly increased the rate of decomposition and defluorination of PFOA irradiated with UV light whereas it decreased both processes under VUV irradiation. Reactive radical (IO 3 ·) generated by photolysis of IO 4 - initiated the oxidation of PFOA in UV process. Aquated electrons (e aq - ), generated from water homolysis, scavenged IO 4 - resulting in decrease of reactive radical species production and PFOA decomposition. The shorter-chain perfluorocarboxylic acids (PFCAs) formed in a stepwise manner from long-chain PFCAs.

Rydberg states of chloroform studied by VUV photoabsorption spectroscopy

International Nuclear Information System (INIS)

Singh, Param Jeet; Shastri, Aparna; D’Souza, R.; Jagatap, B.N.

2013-01-01

The VUV photoabsorption spectra of CHCl 3 and CDCl 3 in the energy region 6.2–11.8 eV (50,000–95,000 cm −1 ) have been investigated using synchrotron radiation from the Indus-1 source. Rydberg series converging to the first four ionization limits at 11.48, 11.91, 12.01 and 12.85 eV corresponding to excitation from the 1a 2 , 4a 1 , 4e, 3e, orbitals of CHCl 3 respectively are identified and analyzed. Quantum defect values are observed to be consistent with excitation from the chlorine lone pair orbitals. Vibrational progressions observed in the region of 72,500–76,500 cm −1 have been reassigned to ν 3 and combination modes of ν 3 +ν 6 belonging to the 1a 2 →4p transition in contrast to earlier studies where they were assigned to a ν 3 progression superimposed on the 3e→4p Rydberg transition. The assignments are further confirmed based on isotopic substitution studies on CDCl 3 whose VUV photoabsorption spectrum is reported here for the first time. The frequencies of the ν 3 and ν 6 modes in the 4p Rydberg state of CHCl 3 (CDCl 3 ) are proposed to be ∼454 (409) cm −1 and∼130 (129) cm −1 respectively based on the vibronic analysis. DFT calculations of neutral and ionic ground state vibrational frequencies support the vibronic analysis. Experimental spectrum is found to be in good agreement with that predicted by TDDFT calculations. This work presents a consolidated analysis of the VUV photoabsorption spectrum of chloroform. -- Highlights: •VUV photoabsorption spectra of CHCl 3 and CDCl 3 studied using synchrotron radiation. •Quantum defect analysis of Rydberg series converging to first four ionization limits. •Vibronic bands in 72,500–76,500 cm −1 region assigned to 1a 2 →4p Rydberg transition. •Vibrational progressions assigned to ν 3 and ν 3 +ν 6 using ab initio calculations. •Excellent agreement of TDDFT vertical excited energies with experimental spectrum

A VUV prism spectrometer for RICH radiator refractometry

CERN Document Server

Moyssides, P G; Fokitis, E

2000-01-01

A prism spectrometer has been developed to operate in the VUV wavelength range from 120 to 200 nm. It can be used as a pre- disperser in conjunction with a Fabry-Perot based gas refractometer. This instrument has also been used to measure the refractive index of the liquid radiator C/sub 6/F/sub 14/ in various spectral lines. This radiator is used in the RICH detectors of the DELPHI experiment and has been proposed for ALICE, and LHCb experiments. The spectral resolution of the system is improved as the wavelength decreases and the data are consistent with a wavelength accuracy about 0.4 nm at 140 nm. The results for the dispersion curve of the above liquid are presented. (17 refs).

Simultaneous removal of NO and SO2 using vacuum ultraviolet light (VUV)/heat/peroxymonosulfate (PMS).

Science.gov (United States)

Liu, Yangxian; Wang, Yan; Wang, Qian; Pan, Jianfeng; Zhang, Jun

2018-01-01

Simultaneous removal process of SO 2 and NO from flue gas using vacuum ultraviolet light (VUV)/heat/peroxymonosulfate (PMS) in a VUV spraying reactor was proposed. The key influencing factors, active species, reaction products and mechanism of SO 2 and NO simultaneous removal were investigated. The results show that vacuum ultraviolet light (185 nm) achieves the highest NO removal efficiency and yield of and under the same test conditions. NO removal is enhanced at higher PMS concentration, light intensity and oxygen concentration, and is inhibited at higher NO concentration, SO 2 concentration and solution pH. Solution temperature has a double impact on NO removal. CO 2 concentration has no obvious effect on NO removal. and produced from VUV-activation of PMS play a leading role in NO removal. O 3 and ·O produced from VUV-activation of O 2 also play an important role in NO removal. SO 2 achieves complete removal under all experimental conditions due to its very high solubility in water and good reactivity. The highest simultaneous removal efficiency of SO 2 and NO reaches 100% and 91.3%, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

VUV Testing of Science Cameras at MSFC: QE Measurement of the CLASP Flight Cameras

Science.gov (United States)

Champey, Patrick R.; Kobayashi, Ken; Winebarger, A.; Cirtain, J.; Hyde, D.; Robertson, B.; Beabout, B.; Beabout, D.; Stewart, M.

2015-01-01

The NASA Marshall Space Flight Center (MSFC) has developed a science camera suitable for sub-orbital missions for observations in the UV, EUV and soft X-ray. Six cameras were built and tested for the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP), a joint National Astronomical Observatory of Japan (NAOJ) and MSFC sounding rocket mission. The CLASP camera design includes a frame-transfer e2v CCD57-10 512x512 detector, dual channel analog readout electronics and an internally mounted cold block. At the flight operating temperature of -20 C, the CLASP cameras achieved the low-noise performance requirements (less than or equal to 25 e- read noise and greater than or equal to 10 e-/sec/pix dark current), in addition to maintaining a stable gain of approximately equal to 2.0 e-/DN. The e2v CCD57-10 detectors were coated with Lumogen-E to improve quantum efficiency (QE) at the Lyman- wavelength. A vacuum ultra-violet (VUV) monochromator and a NIST calibrated photodiode were employed to measure the QE of each camera. Four flight-like cameras were tested in a high-vacuum chamber, which was configured to operate several tests intended to verify the QE, gain, read noise, dark current and residual non-linearity of the CCD. We present and discuss the QE measurements performed on the CLASP cameras. We also discuss the high-vacuum system outfitted for testing of UV and EUV science cameras at MSFC.

National Synchrotron Light Source user's manual: Guide to the VUV and x-ray beamlines

International Nuclear Information System (INIS)

Gmuer, N.F.

1993-04-01

The success of the National Synchrotron Light Source is based, in large part, on the size of the user community and the diversity of the scientific and technical disciplines represented by these users. As evidence of this success, the VUV Ring has just celebrated its 10th anniversary and the X-ray Ring will do the same in 1995. In order to enhance this success, the NSLS User's Manual: Guide to the VUV and X-Ray Beamlines - Fifth Edition, is being published. This Manual presents to the scientific community-at-large the current and projected architecture, capabilities and research programs of the various VUV and X-ray beamlines. Also detailed is the research and computer equipment a General User can expect to find and use at each beamline when working at the NSLS. The Manual is updated periodically in order to keep pace with the constant changes on these beamlines

Simultaneous nitrate reduction and acetaminophen oxidation using the continuous-flow chemical-less VUV process as an integrated advanced oxidation and reduction process.

Science.gov (United States)

Moussavi, Gholamreza; Shekoohiyan, Sakine

2016-11-15

This work was aimed at investigating the performance of the continuous-flow VUV photoreactor as a novel chemical-less advanced process for simultaneously oxidizing acetaminophen (ACT) as a model of pharmaceuticals and reducing nitrate in a single reactor. Solution pH was an important parameter affecting the performance of VUV; the highest ACT oxidation and nitrate reduction attained at solution pH between 6 and 8. The ACT was oxidized mainly by HO while the aqueous electrons were the main working agents in the reduction of nitrate. The performance of VUV photoreactor improved with the increase of hydraulic retention time (HRT); the complete degradation of ACT and ∼99% reduction of nitrate with 100% N2 selectivity achieved at HRT of 80min. The VUV effluent concentrations of nitrite and ammonium at HRT of 80min were below the drinking water standards. The real water sample contaminated with the ACT and nitrate was efficiently treated in the VUV photoreactor. Therefore, the VUV photoreactor is a chemical-less advanced process in which both advanced oxidation and advanced reduction reactions are accomplished. This unique feature possesses VUV photoreactor as a promising method of treating water contaminated with both pharmaceutical and nitrate. Copyright © 2016 Elsevier B.V. All rights reserved.

Semiconductor Electrical Measurements Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The Semiconductor Electrical Measurements Laboratory is a research laboratory which complements the Optical Measurements Laboratory. The laboratory provides for Hall...

A fast VUV light pulser for testing ring-imaging Cerenkov counters

International Nuclear Information System (INIS)

Margulies, S.; Ozelis, J.

1986-01-01

A simple, fast, VUV light pulser for testing a TMAE-based, time-projection-chamber-type photon detector for a ring-imaging Cerenkov counter is described. The pulser consists of an automobile spark plug fired in a controlled atmosphere by a relaxation oscillator. The resulting VUV spectrum, spark-current pulse, and light pulse were investigated for hydrogen, xenon, krypton, and nitrogen fills. The best pulse (3.5 ns FWHM) was obtained with hydrogen at 60 kPa absolute pressure. Xenon was, generally, unsuitable because it continued to emit light for more than a microsecond after excitation. With krypton and nitrogen, no light was emitted in the wavelength region of interest except for a series of sharp lines attributable to the electrodes

Combined UV-C/H2O2-VUV processes for the treatment of an actual slaughterhouse wastewater.

Science.gov (United States)

Naderi, Kambiz Vaezzadeh; Bustillo-Lecompte, Ciro Fernando; Mehrvar, Mehrab; Abdekhodaie, Mohammad Jafar

2017-05-04

In this study, a three-factor, three-level Box-Behnken design with response surface methodology were used to maximize the TOC removal and minimize the H 2 O 2 residual in the effluent of the combined UV-C/H 2 O 2 -VUV system for the treatment of an actual slaughterhouse wastewater (SWW) collected from one of the meat processing plants in Ontario, Canada. The irradiation time and the initial concentrations of total organic carbon (TOC o ) and hydrogen peroxide (H 2 O 2o ) were the three predictors, as independent variables, studied in the design of experiments. The multiple response approach was used to obtain desirability response surfaces at the optimum factor settings. Subsequently, the optimum conditions to achieve the maximum percentage TOC removal of 46.19% and minimum H 2 O 2 residual of 1.05% were TOC o of 213 mg L -1 , H 2 O 2o of 450 mg L -1 , and irradiation time of 9 min. The attained optimal operating conditions were validated with a complementary test. Consequently, the TOC removal of 45.68% and H 2 O 2 residual of 1.03% were achieved experimentally, confirming the statistical model reliability. Three individual processes, VUV alone, VUV/H 2 O 2 , and UV-C/H 2 O 2 , were also evaluated to compare their performance for the treatment of the actual SWW using the optimum parameters obtained in combined UV-C/H 2 O 2 -VUV processes. Results confirmed that an adequate combination of the UV-C/H 2 O 2 -VUV processes is essential for an optimized TOC removal and H 2 O 2 residual. Finally, respirometry analyses were also performed to evaluate the biodegradability of the SWW and the BOD removal efficiency of the combined UV-C/H 2 O 2 -VUV processes.

Rydberg states of chloroform studied by VUV photoabsorption spectroscopy

Science.gov (United States)

Singh, Param Jeet; Shastri, Aparna; D'Souza, R.; Jagatap, B. N.

2013-11-01

The VUV photoabsorption spectra of CHCl3 and CDCl3 in the energy region 6.2-11.8 eV (50,000-95,000 cm-1) have been investigated using synchrotron radiation from the Indus-1 source. Rydberg series converging to the first four ionization limits at 11.48, 11.91, 12.01 and 12.85 eV corresponding to excitation from the 1a2, 4a1, 4e, 3e, orbitals of CHCl3 respectively are identified and analyzed. Quantum defect values are observed to be consistent with excitation from the chlorine lone pair orbitals. Vibrational progressions observed in the region of 72,500-76,500 cm-1 have been reassigned to ν3 and combination modes of ν3+ν6 belonging to the 1a2→4p transition in contrast to earlier studies where they were assigned to a ν3 progression superimposed on the 3e→4p Rydberg transition. The assignments are further confirmed based on isotopic substitution studies on CDCl3 whose VUV photoabsorption spectrum is reported here for the first time. The frequencies of the ν3 and ν6 modes in the 4p Rydberg state of CHCl3 (CDCl3) are proposed to be ~454 (409) cm-1 and~130 (129) cm-1 respectively based on the vibronic analysis. DFT calculations of neutral and ionic ground state vibrational frequencies support the vibronic analysis. Experimental spectrum is found to be in good agreement with that predicted by TDDFT calculations. This work presents a consolidated analysis of the VUV photoabsorption spectrum of chloroform.

VUV action spectroscopy of protonated leucine-enkephalin peptide in the 6-14 eV range

Energy Technology Data Exchange (ETDEWEB)

Ranković, M. Lj. [Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade (Serbia); Canon, F. [INRA, UMR1324 Centre des Sciences du Goût et de l’Alimentation, F-21000 Dijon (France); Nahon, L. [SOLEIL, l’Orme des Merisiers, St Aubin, BP48, 91192 Gif sur Yvette Cedex (France); Giuliani, A. [SOLEIL, l’Orme des Merisiers, St Aubin, BP48, 91192 Gif sur Yvette Cedex (France); INRA, UAR1008, CEPIA, Rue de la Géraudière, BP 71627, 44316 Nantes (France); Milosavljević, A. R., E-mail: vraz@ipb.ac.rs [Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade (Serbia); Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556 (United States)

2015-12-28

We have studied the Vacuum Ultraviolet (VUV) photodissociation of gas-phase protonated leucine-enkephalin peptide ion in the 5.7 to 14 eV photon energy range by coupling a linear quadrupole ion trap with a synchrotron radiation source. We report VUV activation tandem mass spectra at 6.7, 8.4, and 12.8 eV photon energies and photodissociation yields for a number of selected fragments. The obtained results provide insight into both near VUV radiation damage and electronic properties of a model peptide. We could distinguish several absorption bands and assign them to particular electronic transitions, according to previous theoretical studies. The photodissociation yields appear to be very different for the various observed fragmentation channels, depending on both the types of fragments and their position along the peptide backbone. The present results are discussed in light of recent gas-phase spectroscopic data on peptides.

Probing colliding Calcium plasmas with emission and VUV absorption imaging

International Nuclear Information System (INIS)

Kavanagh, K.D.; Hirsch, J.S.; Kennedy, E.T.; Costello, T.; Poletto, L.; Nicolosi, P.

2004-01-01

Full text: Laser produced plasmas are formed when a short pulse and high power laser is focused onto a surface. Applications range from VUV/X-ray sources for lithography, microscopy and radiography to X-ray lasers, thin film deposition, analytical spectroscopy and electron/ion beam generation (and even acceleration). A battery of particle and optical techniques are now used to diagnose laser plasmas. One highly successful technique is gated-CCD (Charged Coupled Device) imaging of plasma plumes. It provides critical data on the early (creation) and late (expansion) phases of plasma plumes. However, this technique is limited to detecting only the excited (emitting) species in the plume. Recently, we developed a vacuum-UV (VUV) photoabsorption imaging facility called VPIF which enables one can track the evolution of dark plume matter or non-emitting plasma species residing in ground and metastable states. Although much is known about the dynamics of single laser plasma plumes expanding freely, little is known about the overlap between colliding plasma plumes. We are currently performing combined conventional gated CCD imaging and spectroscopy with VUV absorption imaging to map the evolution of the overlap volume of two colliding and interpenetrating plasma plumes. We are specifically tracking ground state singly ionized calcium in the plasmas by tuning into the inner shell 3p to 3d transition at 33.2 eV while the excited state species are tracked using transitions in the UV -NIR spectral range. The experiment may be cast as a model system for atmospheric and/or astrophysical colliding systems, e.g., when tracer elements are injected into supersonic winds at high altitude or when supernovae eject plasma into the solar wind

Relaxation and excitation electronic processes in dielectrics irradiated by ultrafast IR and VUV pulses

International Nuclear Information System (INIS)

Gaudin, J.

2005-11-01

We studied excitation and relaxation of electrons involved during interaction of visible and VUV femtosecond pulses with dielectrics. The generated population of hot electrons, having energy of few eV to few tens of eV above the bottom of the conduction band, is responsible of phenomena ranging to defect creation to optical breakdown. Owing to two techniques: photoemission and transient photoconductivity we improve the understanding of the The first photoemission experiments deal with dielectrics irradiated by 30 fs IR pulses. The photoemission spectra measured show a large population of electrons which energy rise up to 40 eV. We interpret this result in terms of a new absorption process: direct multi-photons inter-branch transitions. The 2. type of photoemission experiments are time resolved 'pump/probe' investigation. We study the relaxation of electrons excited by a VUV pulses. We used the high order harmonics (HOH) as light sources. We found surprisingly long decay time in the range of ps timescale. Last type of experiments is photoconductivity studies of diamond samples. Using HOH as light source we measure the displacement current induced by excited electrons in the conduction band. Those electrons relax mainly by impact ionisation creating secondary electrons. Hence by probing the number of electrons we were able to measure the efficiency of these relaxation processes. We observe a diminution of this efficiency when the energy of exciting photons is above 20 eV. Owing to Monte-Carlo simulation we interpret this result in terms of band structure effect. (author)

Hydrocarbons in interstellar ice analogues : UV-vis spectroscopy and VUV photochemistry

NARCIS (Netherlands)

Cuylle, Steven Hendrik

2015-01-01

This thesis treats the chemical behaviour of carbonaceous molecules in water-dominated interstellar ices. VUV photons are considered as the chemical trigger to induce solid state chemistry as it is omnipresent. Lyman- radiation occurs even in dense molecular clouds as a result of cosmic ray

DOE/DMS workshop on future synchrotron VUV and x-ray beam Lines

International Nuclear Information System (INIS)

Green, P.H.

1992-03-01

This document contains an overview of the participating DOE Laboratory beam line interests and the projected science to be addressed on these beam lines, both at new and existing synchrotron facilities. The scientific programs associated with present and planned synchrotron research by DOE Laboratories are discussed in chapters titled ''VUV and Soft X-Ray Research'' and ''Hard X-Ray Research.'' This research encompasses a broad range of the nation's scientific and technical research needs from fundamental to applied, in areas including environmental, biological, and physical sciences; new materials; and energy-related technologies. The projected cost of this proposed construction has been provided in tabular form using a uniform format so that anticipated DOE and outside funding agency contributions for construction and for research and development can be determined. The cost figures are, of course, subject to uncertainties of detailed design requirements and the availability of facility-designed generic components and outside vendors. The report also contains a compendium (as submitted by the beam line proposers) of the design capabilities, the anticipated costs, and the scientific programs of projected beam line construction at the four synchrotron facilities. A summary of the projected cost of these beam lines to be requested of DOE is compiled

VUV photo-oxidation of gaseous benzene combined with ozone-assisted catalytic oxidation: Effect on transition metal catalyst

International Nuclear Information System (INIS)

Huang, Haibao; Lu, Haoxian; Zhan, Yujie; Liu, Gaoyuan; Feng, Qiuyu; Huang, Huiling; Wu, Muyan; Ye, Xinguo

2017-01-01

Graphical abstract: Mn nanoparticles are highly dispersed on ZSM-5 and most efficient in benzene degradation in the VUV-OZCO process. - Highlights: • Vacuum UV irradiation is well combined with O_3 catalytic oxidation. • O_3 byproducts was used to enhance catalytic oxidation of VOCs. • Mn/ZSM-5 achieved the best catalytic activity for benzene degradation. - Abstract: Volatile organic compounds (VOCs) cause the major air pollution concern. In this study, a series of ZSM-5 supported transition metals were prepared by impregnation method. They were combined with vacuum UV (VUV) photo-oxidation in a continuous-flow packed-bed reactor and used for the degradation of benzene, a typical toxic VOCs. Compared with VUV photo-oxidation alone, the introduction of catalysts can greatly enhance benzene oxidation under the help of O_3, the by-products from VUV irradiation, via ozone-assisted catalytic oxidation (OZCO). The catalytic activity of transition metals towards benzene oxidation followed the order: Mn > Co > Cu > Ni > Fe. Mn achieved the best catalytic activity due to the strongest capability for O_3 catalytic decomposition and utilization. Benzene and O_3 removal efficiency reached as high as 97% and 100% after 360 min, respectively. O_3 was catalytically decomposed, generating highly reactive oxidants such as ·OH and ·O for benzene oxidation.

VUV photo-oxidation of gaseous benzene combined with ozone-assisted catalytic oxidation: Effect on transition metal catalyst

Energy Technology Data Exchange (ETDEWEB)

Huang, Haibao, E-mail: seabao8@gmail.com [School of Environmental Science and Engineering, Sun Yat-Sen University (China); Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology (Sun Yat-sen University) (China); Lu, Haoxian; Zhan, Yujie; Liu, Gaoyuan; Feng, Qiuyu; Huang, Huiling; Wu, Muyan; Ye, Xinguo [School of Environmental Science and Engineering, Sun Yat-Sen University (China)

2017-01-01

Graphical abstract: Mn nanoparticles are highly dispersed on ZSM-5 and most efficient in benzene degradation in the VUV-OZCO process. - Highlights: • Vacuum UV irradiation is well combined with O{sub 3} catalytic oxidation. • O{sub 3} byproducts was used to enhance catalytic oxidation of VOCs. • Mn/ZSM-5 achieved the best catalytic activity for benzene degradation. - Abstract: Volatile organic compounds (VOCs) cause the major air pollution concern. In this study, a series of ZSM-5 supported transition metals were prepared by impregnation method. They were combined with vacuum UV (VUV) photo-oxidation in a continuous-flow packed-bed reactor and used for the degradation of benzene, a typical toxic VOCs. Compared with VUV photo-oxidation alone, the introduction of catalysts can greatly enhance benzene oxidation under the help of O{sub 3}, the by-products from VUV irradiation, via ozone-assisted catalytic oxidation (OZCO). The catalytic activity of transition metals towards benzene oxidation followed the order: Mn > Co > Cu > Ni > Fe. Mn achieved the best catalytic activity due to the strongest capability for O{sub 3} catalytic decomposition and utilization. Benzene and O{sub 3} removal efficiency reached as high as 97% and 100% after 360 min, respectively. O{sub 3} was catalytically decomposed, generating highly reactive oxidants such as ·OH and ·O for benzene oxidation.

VUV Pump and Probe of Phase Separation and Oxygen Interstitials in La2NiO4+y Using Spectromicroscopy

Directory of Open Access Journals (Sweden)

Antonio Bianconi

2018-02-01

Full Text Available While it is known that strongly correlated transition metal oxides described by a multi-band Hubbard model show microscopic multiscale phase separation, little is known about the possibility to manipulate them with vacuum ultraviolet (VUV, 27 eV lighting. We have investigated the photo-induced effects of VUV light illumination of a super-oxygenated La2NiO4+y single crystal by means of scanning photoelectron microscopy. VUV light exposure induces the increase of the density of states (DOS in the binding energy range around Eb = 1.4 eV below EF. The photo-induced states in this energy region have been predicted due to clustering of oxygen interstitials by band structure calculations for large supercell of La2CuO4.125. We finally show that it is possible to generate and manipulate oxygen rich domains by VUV illumination as it was reported for X-ray illumination of La2CuO4+y. This phenomenology is assigned to oxygen-interstitials ordering and clustering by photo-illumination forming segregated domains in the La2NiO4+y surface.

VUV photo-oxidation of gaseous benzene combined with ozone-assisted catalytic oxidation: Effect on transition metal catalyst

Science.gov (United States)

Huang, Haibao; Lu, Haoxian; Zhan, Yujie; Liu, Gaoyuan; Feng, Qiuyu; Huang, Huiling; Wu, Muyan; Ye, Xinguo

2017-01-01

Volatile organic compounds (VOCs) cause the major air pollution concern. In this study, a series of ZSM-5 supported transition metals were prepared by impregnation method. They were combined with vacuum UV (VUV) photo-oxidation in a continuous-flow packed-bed reactor and used for the degradation of benzene, a typical toxic VOCs. Compared with VUV photo-oxidation alone, the introduction of catalysts can greatly enhance benzene oxidation under the help of O3, the by-products from VUV irradiation, via ozone-assisted catalytic oxidation (OZCO). The catalytic activity of transition metals towards benzene oxidation followed the order: Mn > Co > Cu > Ni > Fe. Mn achieved the best catalytic activity due to the strongest capability for O3 catalytic decomposition and utilization. Benzene and O3 removal efficiency reached as high as 97% and 100% after 360 min, respectively. O3 was catalytically decomposed, generating highly reactive oxidants such as rad OH and rad O for benzene oxidation.

VUV-sensitive silicon-photomultipliers for the nEXO-experiment

Energy Technology Data Exchange (ETDEWEB)

Wrede, Gerrit; Bayerlein, Reimund; Hufschmidt, Patrick; Jamil, Ako; Schneider, Judith; Wagenpfeil, Michael; Ziegler, Tobias; Hoessl, Juergen; Anton, Gisela; Michel, Thilo [ECAP, Friedrich-Alexander-Universitaet Erlangen-Nuernberg (Germany)

2016-07-01

The nEXO (next Enriched Xenon Observatory) experiment will search for the neutrinoless double beta decay of Xe-136 with a liquid xenon TPC (Time ProjectionChamber). The sensitivity of the experiment is related to the energy resolution, which itself depends on the accuracies of the measurements of the amount of drifting electrons and the number of scintillation photons with their wavelength being in the vacuum ultraviolet band. Silicon Photomultipliers (SiPM) shall be used for the detection of the scintillation light, since they can be produced extremely radiopure. Commercially available SiPM do not fulfill all requirements of the nEXO experiment, thus a dedicated development is necessary. To characterize the silicon photomultipliers, we have built a test apparatus for xenon liquefaction, in which a VUV-sensitive photomultiplier tube can be operated together with the SiPM. In this contribution we present our apparatus for the SiPM characterization measurements and our latest results on the test of the silicon photomultipliers for the detection of xenon scintillation light.

Future prospects for studies in the VUV-SX region

International Nuclear Information System (INIS)

Tanaka, Kenichiro; Kitajima, Yoshinori

1989-09-01

This book carries papers presented at a workshop 'Future Prospects for Studies in the VUV-SX Region' held on March 22 and 23, 1989. The workshop focussed particularly on the promotion of research in the VUV and soft X-ray regions. Three sessions were held: Session 1 for studies in peripheral areas, Session 2 for theoretical studies, and Session 3 for recent developments. Session 1 covered five studies: 'Laser Spectroscopy: High-Resolution Observation of Highly Electronically Excited Gaseous Molecule', 'High-Resolution Electron Spectroscopy: Surface Phonon Spectroscopy', 'Experimental Study on Atoms and Molecules through Ion Trap', 'Basic Mechanism of Photo-Induced CVD', and 'Application of Circularly Polarized Light'. Session 2 covered five studies: 'Electronic State of High Tc Superconducting Oxide', 'Surface Condition and Electronic State', 'XES and XAS Study of Rare Earth Compound', 'Resonance Photoelectric Spectroscopy on Strongly Correlated Electronic System', and 'Circularly Polarized Light and Atomic Process in Soft X-Ray Region'. Session 3 covered six studies: 'Prospects of Application of Supercritical Liquid to Research on Physical Characteristics', 'Application of Orbit Radiation to Polarization Spectroscopy', 'XES Research for La Compounds', 'Characteristics of Ultra-Fine Particles', 'Surface Study by Angular-Resolution Photoelectric Spectroscopy', and 'EXAFS Study of Light Element'. (N.K.)

Beam line design for synchrotron spectroscopy in the VUV

Energy Technology Data Exchange (ETDEWEB)

Howells, M R

1980-01-01

The character of the radiation source provided by an electron storage ring is briefly reviewed from the point of view of utilization for VUV spectroscopy. The design of beam line components is then considered with special reference to the problems of contamination of optical surfaces and vacuum protection. The issues involved in designing mirrors for use with storage rings are considered with emphasis on the questions of power dissipation, image quality and materials selection.

Beam line design for synchrotron spectroscopy in the VUV

International Nuclear Information System (INIS)

Howells, M.R.

1980-01-01

The character of the radiation source provided by an electron storage ring is briefly reviewed from the point of view of utilization for VUV spectroscopy. The design of beam line components is then considered with special reference to the problems of contamination of optical surfaces and vacuum protection. The issues involved in designing mirrors for use with storage rings are considered with emphasis on the questions of power dissipation, image quality and materials selection

Photocatalytic oxidation of indoor toluene: Process risk analysis and influence of relative humidity, photocatalysts, and VUV irradiation

International Nuclear Information System (INIS)

Zhao, Weirong; Dai, Jiusong; Liu, Feifei; Bao, Jiaze; Wang, Yan; Yang, Yong; Yang, Yanan; Zhao, Dongye

2012-01-01

Concentrations of 13 gaseous intermediates in photocatalytic oxidation (PCO) of toluene in indoor air were determined in real-time by proton transfer reaction mass spectrometry and desorption intensities of 7 adsorbed intermediates on the surface of photocatalysts were detected by temperature‐programmed desorption‐mass spectrometry. Effects of relative humidity (RH), photocatalysts, and vacuum ultraviolet (VUV) irradiation on the distribution and category of the intermediates and health risk influence index (η) were investigated. RH enhances the formation rate of hydroxide radicals, leading to more intermediates with higher oxidation states in gas phase. N doping promotes the separation of photo-generated electrons and holes and enhances PCO activity accordingly. VUV irradiation results in higher mineralization rate and more intermediates with higher oxidation states and lower toxicity e.g. carboxylic acids. Health risk analysis indicates that higher RH, N doping of TiO 2 , and VUV lead to “greener” intermediates and smaller η. Finally, a conceptual diagram was proposed to exhibit the scenario of η varied with extent of mineralization for various toxicities of inlet pollutants. Highlights: ► 13 volatile intermediates in PCO of toluene were determined in real-time by PTR-MS. ► 7 adsorbed intermediates on surface of photocatalyst were determined by TPD-MS. ► Higher RH, N doping of TiO 2 , and VUV irradiation lead to “greener” intermediates. ► Health risk index relies on extent of mineralization and toxicities of inlet VOCs.

VUV photo-processing of PAH cations: quantitative study on the ionization versus fragmentation processes.

Science.gov (United States)

Zhen, Junfeng; Castillo, Sarah Rodriguez; Joblin, Christine; Mulas, Giacomo; Sabbah, Hassan; Giuliani, Alexandre; Nahon, Laurent; Martin, Serge; Champeaux, Jean-Philippe; Mayer, Paul M

2016-05-10

Interstellar polycyclic aromatic hydrocarbons (PAHs) are strongly affected by the absorption of vacuum ultraviolet (VUV) photons in the interstellar medium (ISM), yet the branching ratio between ionization and fragmentation is poorly studied. This is crucial for the stability and charge state of PAHs in the ISM in different environments, affecting in turn the chemistry, the energy balance, and the contribution of PAHs to the extinction and emission curves. We studied the interaction of PAH cations with VUV photons in the 7 - 20 eV range from the synchrotron SOLEIL beamline, DESIRS. We recorded by action spectroscopy the relative intensities of photo-fragmentation and photo-ionization for a set of eight PAH cations ranging in size from 14 to 24 carbon atoms, with different structures. At photon energies below ~13.6 eV fragmentation dominates for the smaller species, while for larger species ionization is immediately competitive after the second ionization potential (IP). At higher photon energies, all species behave similarly, the ionization yield gradually increases, leveling off between 0.8 and 0.9 at ~18 eV. Among isomers, PAH structure appears to mainly affect the fragmentation cross section, but not the ionization cross section. We also measured the second IP for all species and the third IP for two of them, all are in good agreement with theoretical ones confirming that PAH cations can be further ionized in the diffuse ISM. Determining actual PAH dication abundances in the ISM will require detailed modeling. Our measured photo-ionization yields for several PAH cations provide a necessary ingredient for such models.

VUV PHOTO-PROCESSING OF PAH CATIONS: QUANTITATIVE STUDY ON THE IONIZATION VERSUS FRAGMENTATION PROCESSES

Energy Technology Data Exchange (ETDEWEB)

Zhen, Junfeng; Castillo, Sarah Rodriguez; Joblin, Christine; Mulas, Giacomo; Sabbah, Hassan [Université de Toulouse, UPS-OMP, Institut de Recherche en Astrophysique et Planétologie, Toulouse (France); Giuliani, Alexandre; Nahon, Laurent [Synchrotron SOLEIL, LOrme des Merisiers, F-91192 Gif sur Yvette Cedex (France); Martin, Serge [Institut Lumière Matière, Université Lyon 1-CNRS, Université de Lyon, F-69622 Villeurbanne cedex (France); Champeaux, Jean-Philippe [Laboratoire Collisions Agrégats Réactivité, Université de Toulouse, UPS-IRSAMC, CNRS, 118 Route de Narbonne, Bat 3R1B4, F-31062 Toulouse Cedex 9 (France); Mayer, Paul M., E-mail: christine.joblin@irap.omp.eu [Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa K1N 6N5 (Canada)

2016-05-10

Interstellar polycyclic aromatic hydrocarbons (PAHs) are strongly affected by the absorption of vacuum ultraviolet (VUV) photons in the interstellar medium (ISM), yet the branching ratio between ionization and fragmentation is poorly studied. This is crucial for the stability and charge state of PAHs in the ISM in different environments, affecting in turn the chemistry, the energy balance, and the contribution of PAHs to the extinction and emission curves. We studied the interaction of PAH cations with VUV photons in the 7–20 eV range from the synchrotron SOLEIL beamline, DESIRS. We recorded by action spectroscopy the relative intensities of photo-fragmentation and photo-ionization for a set of eight PAH cations ranging in size from 14 to 24 carbon atoms, with different structures. At photon energies below ∼13.6 eV fragmentation dominates for the smaller species, while for larger species ionization is immediately competitive after the second ionization potential (IP). At higher photon energies all species behave similarly; the ionization yield gradually increases, leveling off between 0.8 and 0.9 at ∼18 eV. Among isomers, PAH structure appears to mainly affect the fragmentation cross section but not the ionization cross section. We also measured the second IP for all species and the third IP for two of them; all are in good agreement with theoretical ones, confirming that PAH cations can be further ionized in the diffuse ISM. Determining actual PAH dication abundances in the ISM will require detailed modeling. Our measured photo-ionization yields for several PAH cations provide a necessary ingredient for such models.

VUV PHOTO-PROCESSING OF PAH CATIONS: QUANTITATIVE STUDY ON THE IONIZATION VERSUS FRAGMENTATION PROCESSES

International Nuclear Information System (INIS)

Zhen, Junfeng; Castillo, Sarah Rodriguez; Joblin, Christine; Mulas, Giacomo; Sabbah, Hassan; Giuliani, Alexandre; Nahon, Laurent; Martin, Serge; Champeaux, Jean-Philippe; Mayer, Paul M.

2016-01-01

Interstellar polycyclic aromatic hydrocarbons (PAHs) are strongly affected by the absorption of vacuum ultraviolet (VUV) photons in the interstellar medium (ISM), yet the branching ratio between ionization and fragmentation is poorly studied. This is crucial for the stability and charge state of PAHs in the ISM in different environments, affecting in turn the chemistry, the energy balance, and the contribution of PAHs to the extinction and emission curves. We studied the interaction of PAH cations with VUV photons in the 7–20 eV range from the synchrotron SOLEIL beamline, DESIRS. We recorded by action spectroscopy the relative intensities of photo-fragmentation and photo-ionization for a set of eight PAH cations ranging in size from 14 to 24 carbon atoms, with different structures. At photon energies below ∼13.6 eV fragmentation dominates for the smaller species, while for larger species ionization is immediately competitive after the second ionization potential (IP). At higher photon energies all species behave similarly; the ionization yield gradually increases, leveling off between 0.8 and 0.9 at ∼18 eV. Among isomers, PAH structure appears to mainly affect the fragmentation cross section but not the ionization cross section. We also measured the second IP for all species and the third IP for two of them; all are in good agreement with theoretical ones, confirming that PAH cations can be further ionized in the diffuse ISM. Determining actual PAH dication abundances in the ISM will require detailed modeling. Our measured photo-ionization yields for several PAH cations provide a necessary ingredient for such models.

VUV photo-processing of PAH cations: quantitative study on the ionization versus fragmentation processes

Science.gov (United States)

Zhen, Junfeng; Castillo, Sarah Rodriguez; Joblin, Christine; Mulas, Giacomo; Sabbah, Hassan; Giuliani, Alexandre; Nahon, Laurent; Martin, Serge; Champeaux, Jean-Philippe; Mayer, Paul M.

2016-01-01

Interstellar polycyclic aromatic hydrocarbons (PAHs) are strongly affected by the absorption of vacuum ultraviolet (VUV) photons in the interstellar medium (ISM), yet the branching ratio between ionization and fragmentation is poorly studied. This is crucial for the stability and charge state of PAHs in the ISM in different environments, affecting in turn the chemistry, the energy balance, and the contribution of PAHs to the extinction and emission curves. We studied the interaction of PAH cations with VUV photons in the 7 – 20 eV range from the synchrotron SOLEIL beamline, DESIRS. We recorded by action spectroscopy the relative intensities of photo-fragmentation and photo-ionization for a set of eight PAH cations ranging in size from 14 to 24 carbon atoms, with different structures. At photon energies below ~13.6 eV fragmentation dominates for the smaller species, while for larger species ionization is immediately competitive after the second ionization potential (IP). At higher photon energies, all species behave similarly, the ionization yield gradually increases, leveling off between 0.8 and 0.9 at ~18 eV. Among isomers, PAH structure appears to mainly affect the fragmentation cross section, but not the ionization cross section. We also measured the second IP for all species and the third IP for two of them, all are in good agreement with theoretical ones confirming that PAH cations can be further ionized in the diffuse ISM. Determining actual PAH dication abundances in the ISM will require detailed modeling. Our measured photo-ionization yields for several PAH cations provide a necessary ingredient for such models. PMID:27212712

Luminescent properties of (Y,Gd)BO3:Bi3+,RE3+ (RE=Eu, Tb) phosphor under VUV/UV excitation

International Nuclear Information System (INIS)

Zeng Xiaoqing; Im, Seoung-Jae; Jang, Sang-Hun; Kim, Young-Mo; Park, Hyoung-Bin; Son, Seung-Hyun; Hatanaka, Hidekazu; Kim, Gi-Young; Kim, Seul-Gi

2006-01-01

Bi 3+ - and RE 3+ -co-doped (Y,Gd)BO 3 phosphors were prepared and their luminescent properties under vacuum ultraviolet (VUV)/UV excitation were investigated. Strong red emission for (Y,Gd)BO 3 :Bi 3+ ,Eu 3+ and strong green emission for (Y,Gd)BO 3 :Bi 3+ ,Tb 3+ are observed under VUV excitation from 147 to 200 nm with a much broader excitation region than that of single Eu 3+ -doped or Tb 3+ -doped (Y,Gd)BO 3 phosphor. Strong emissions are also observed under UV excitation around 265 nm where as nearly no luminescence is observed for single Eu 3+ -doped or Tb 3+ -doped (Y,Gd)BO 3 . The luminescence enhancement of Bi 3+ - and RE 3+ -co-doped (Y,Gd)BO 3 phosphors is due to energy transfer from Bi 3+ ion to Eu 3+ or Tb 3+ ion not only in the VUV region but also in the UV region. Besides, host sensitization competition between Bi 3+ and Eu 3+ or Tb 3+ is also observed. The investigated phosphors may be preferable for devices with a VUV light 147-200 nm as an excitation source such as PDP or mercury-free fluorescent lamp

Production and detection of axion-like particles at the VUV-FEL. Letter of intent

International Nuclear Information System (INIS)

Koetz, U.; Ringwald, A.; Tschentscher, T.

2006-06-01

Recently, the PVLAS collaboration has reported evidence for an anomalously large rotation of the polarization of light generated in vacuum in the presence of a transverse magnetic field. This may be explained through the production of a new light spin-zero particle coupled to two photons. In this Letter of Intent, we propose to test this hypothesis by setting up a photon regeneration experiment which exploits the photon beam of the Vacuum-UltraViolet Free-Electron Laser VUV-FEL, sent along the transverse magnetic field of a linear arrangement of dipole magnets of size B L ∼ 30 Tm. The high photon energies available at the VUV-FEL increase substantially the expected photon regeneration rate in the mass range implied by the PVLAS anomaly, in comparison to the rate expected at visible lasers of similar power. We find that the particle interpretation of the PVLAS result can be tested within a short running period. The pseudoscalar vs. scalar nature can be determined by varying the direction of the magnetic field with respect to the laser polarization. The mass of the particle can be measured by running at different photon energies. The proposed experiment offers a window of opportunity for a firm establishment or exclusion of the particle interpretation of the PVLAS anomaly before other experiments can compete. (Orig.)

Time-resolved VUV spectroscopy in the EXTRAP-T2 reversed field pinch

International Nuclear Information System (INIS)

Hedqvist, A.; Rachlew-Kaellne, E.

1998-01-01

Time-resolved VUV spectroscopy has been used to investigate the effects of impurities in a reversed field pinch operating with a resistive shell. Results of electron temperature, impurity ion densities, particle confinement time and Z eff together with a description of the interpretation and the equipment are presented. (author)

Vacuum ultraviolet emission spectrum measurement of a microwave-discharge hydrogen-flow lamp in several configurations: Application to photodesorption of CO ice

Energy Technology Data Exchange (ETDEWEB)

Chen, Y.-J.; Wu, C.-Y. R. [Space Sciences Center and Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089-1341 (United States); Chuang, K.-J.; Chu, C.-C.; Yih, T.-S. [Department of Physics, National Central University, Jhongli City, Taoyuan County 32054, Taiwan (China); Muñoz Caro, G. M. [Centro de Astrobiología, INTA-CSIC, Torrejón de Ardoz, E-28850 Madrid (Spain); Nuevo, M. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Ip, W.-H., E-mail: yujung@usc.edu [Graduate Institute of Astronomy, National Central University, Jhongli City, Taoyuan County 32049, Taiwan (China)

2014-01-20

We report measurements of the vacuum ultraviolet (VUV) emission spectra of a microwave-discharge hydrogen-flow lamp (MDHL), a common tool in astrochemistry laboratories working on ice VUV photoprocessing. The MDHL provides hydrogen Ly-α (121.6 nm) and H{sub 2} molecular emission in the 110-180 nm range. We show that the spectral characteristics of the VUV light emitted in this range, in particular the relative proportion of Ly-α to molecular emission bands, strongly depend on the pressure of H{sub 2} inside the lamp, the lamp geometry (F type versus T type), the gas used (pure H{sub 2} versus H{sub 2} seeded in He), and the optical properties of the window used (MgF{sub 2} versus CaF{sub 2}). These different configurations are used to study the VUV irradiation of CO ice at 14 K. In contrast to the majority of studies dedicated to the VUV irradiation of astrophysical ice analogs, which have not taken into consideration the emission spectrum of the MDHL, our results show that the processes induced by photons in CO ice from a broad energy range are different and more complex than the sum of individual processes induced by monochromatic sources spanning the same energy range, as a result of the existence of multistate electronic transitions and discrepancy in absorption cross sections between parent molecules and products in the Ly-α and H{sub 2} molecular emission ranges.

Vacuum ultraviolet emission spectrum measurement of a microwave-discharge hydrogen-flow lamp in several configurations: Application to photodesorption of CO ice

International Nuclear Information System (INIS)

Chen, Y.-J.; Wu, C.-Y. R.; Chuang, K.-J.; Chu, C.-C.; Yih, T.-S.; Muñoz Caro, G. M.; Nuevo, M.; Ip, W.-H.

2014-01-01

We report measurements of the vacuum ultraviolet (VUV) emission spectra of a microwave-discharge hydrogen-flow lamp (MDHL), a common tool in astrochemistry laboratories working on ice VUV photoprocessing. The MDHL provides hydrogen Ly-α (121.6 nm) and H 2 molecular emission in the 110-180 nm range. We show that the spectral characteristics of the VUV light emitted in this range, in particular the relative proportion of Ly-α to molecular emission bands, strongly depend on the pressure of H 2 inside the lamp, the lamp geometry (F type versus T type), the gas used (pure H 2 versus H 2 seeded in He), and the optical properties of the window used (MgF 2 versus CaF 2 ). These different configurations are used to study the VUV irradiation of CO ice at 14 K. In contrast to the majority of studies dedicated to the VUV irradiation of astrophysical ice analogs, which have not taken into consideration the emission spectrum of the MDHL, our results show that the processes induced by photons in CO ice from a broad energy range are different and more complex than the sum of individual processes induced by monochromatic sources spanning the same energy range, as a result of the existence of multistate electronic transitions and discrepancy in absorption cross sections between parent molecules and products in the Ly-α and H 2 molecular emission ranges.

Efficient degradation of H2S over transition metal modified TiO2 under VUV irradiation: Performance and mechanism

Science.gov (United States)

Liu, Gaoyuan; Ji, Jian; Hu, Peng; Lin, Sixin; Huang, Haibao

2018-03-01

Odor pollution causes great harm to the atmospheric environment and human health. H2S, as an odor gas, is highly toxic and corrosive and thus requires removal efficiently. In this study, TiO2 catalysts modified by transition metals including Mn, Cu, Ni and Co, were prepared using a modified sol-gelatin method and tested under UV-PCO or VUV-PCO process. H2S degradation was great enhanced in VUV-PCO compared with conventional UV-PCO. Among the catalysts, 1 wt% Mn-TiO2 showed the highest removal efficiency of 89.9%, which is 30 times higher than that under 254 nm UV irradiation. Residual ozone in the outlet can be completely eliminated by Mn-TiO2. Photocatalytic oxidation, photolysis and ozone-assisted catalytic oxidation all involved in the VUV-PCO process and their contribution were determined by H2S removal efficiency.

Atomic and molecular effects in the VUV spectra of solids

International Nuclear Information System (INIS)

Sonntag, B.

1977-10-01

The VUV spectra of solids are often dominated by atomic or molecular effects, which clearly manifest themselves in the gross features of the spectra and the fine structure at inner shell excitation thresholds. Evidence for the influence of atomic and molecular matrix elements, multiplet-splitting and correlation is presented. Special emphasis is given to the direct experimental verification based on the comparison of atomic and solid state spectra. (orig.) [de

VUV spectroscopy and photochemistry of five interstellar and putative prebiotic molecules

Science.gov (United States)

Schwell, M.; Gaie-Levrel, F.; Bénilan, Y.; Gazeau, M.-C.; Fray, N.; Saul, G.; Champion, N.; Leach, S.; Guillemin, J.-C.

2012-02-01

For many years, our group has been investigating the VUV spectroscopy and photochemistry of molecules of astrophysical (Jochims et al. 2006a,b; Leach et al. 2008; Schwell et al. 2012) and prebiotic interest (Schwell et al. 2006). Polyynes and cyano-polyynes that are abundant in the interstellar medium (ISM) and in planetary atmospheres, have been investigated too (e.g. Fray et al. 2010). An aerosol source for reactive and thermo-labile compounds has been developed (Gaie-Levrel et al. 2011) to perform gas-phase measurements. These are necessary to measure intrinsic molecular properties and to compare to quantum chemical calculations. Besides measuring absolute absorption and photoionization cross sections, dissociative channels and their involved excited states are identified for a number of molecules of interstellar interest. Branching ratios of the respective elementary photoreactions are determined in order to understand and model the photochemistry occurring in the ISM. Some very recent results on the dissociative photoionization of methylformate (MF), glycolaldehyde (GA), dimethylether (DIM), aminoacetonitrile (AAC) and cyanoacetylene (CA), are presented here.

Behaviour of large-area avalanche photodiodes under intense magnetic fields for VUV- visible- and X-ray photon detection

International Nuclear Information System (INIS)

Fernandes, L.M.P.; Antognini, A.; Boucher, M.; Conde, C.A.N.; Huot, O.; Knowles, P.; Kottmann, F.; Ludhova, L.; Mulhauser, F.; Pohl, R.; Schaller, L.A.; Santos, J.M.F. dos; Taqqu, D.; Veloso, J.F.C.A.

2003-01-01

The behaviour of large-area avalanche photodiodes for X-rays, visible and vacuum-ultra-violet (VUV) light detection in magnetic fields up to 5 T is described. For X-rays and visible light detection, the photodiode pulse amplitude and energy resolution were unaffected from 0 to 5 T, demonstrating the insensitivity of this type of detector to strong magnetic fields. For VUV light detection, however, the photodiode relative pulse amplitude decreases with increasing magnetic field intensity reaching a reduction of about 24% at 5 T, and the energy resolution degrades noticeably with increasing magnetic field

National Synchrotron Light Source users manual: Guide to the VUV and x-ray beam lines

International Nuclear Information System (INIS)

Gmuer, N.F.; White-DePace, S.M.

1987-08-01

The success of the National Synchrotron Light Source in the years to come will be based, in large part, on the size of the users community and the diversity of the scientific disciplines represented by these users. In order to promote this philosophy, this National Synchrotron Light Source (NSLS) Users Manual: Guide to the VUV and X-Ray Beam Lines, has been published. This manual serves a number of purposes. In an effort to attract new research, it will present to the scientific community-at-large the current and projected architecture and capabilities of the various VUV and x-ray beam lines and storage rings. We anticipate that this publication will be updated periodically in order to keep pace with the constant changes at the NSLS

Time-resolved VUV spectroscopy in the EXTRAP-T2 reversed field pinch

Science.gov (United States)

Hedqvist, Anders; Rachlew-Källne, Elisabeth

1998-09-01

Time-resolved VUV spectroscopy has been used to investigate the effects of impurities in a reversed field pinch operating with a resistive shell. Results of electron temperature, impurity ion densities, particle confinement time and 0741-3335/40/9/004/img1 together with a description of the interpretation and the equipment are presented.

Vacuum ultraviolet spectropolarimeter design for precise polarization measurements.

Science.gov (United States)

Narukage, Noriyuki; Auchère, Frédéric; Ishikawa, Ryohko; Kano, Ryouhei; Tsuneta, Saku; Winebarger, Amy R; Kobayashi, Ken

2015-03-10

Precise polarization measurements in the vacuum ultraviolet (VUV) region provide a new means for inferring weak magnetic fields in the upper atmosphere of the Sun and stars. We propose a VUV spectropolarimeter design ideally suited for this purpose. This design is proposed and adopted for the NASA-JAXA chromospheric lyman-alpha spectropolarimeter (CLASP), which will record the linear polarization (Stokes Q and U) of the hydrogen Lyman-α line (121.567 nm) profile. The expected degree of polarization is on the order of 0.1%. Our spectropolarimeter has two optically symmetric channels to simultaneously measure orthogonal linear polarization states with a single concave diffraction grating that serves both as the spectral dispersion element and beam splitter. This design has a minimal number of reflective components with a high VUV throughput. Consequently, these design features allow us to minimize the polarization errors caused by possible time variation of the VUV flux during the polarization modulation and by statistical photon noise.

Semiconductor Laser Measurements Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The Semiconductor Laser Measurements Laboratory is equipped to investigate and characterize the lasing properties of semiconductor diode lasers. Lasing features such...

Precision VUV Spectro-Polarimetry for Solar Chromospheric Magnetic Field Measurements

Science.gov (United States)

Ishikawa, R.; Bando, T.; Hara, H.; Ishikawa, S.; Kano, R.; Kubo, M.; Katsukawa, Y.; Kobiki, T.; Narukage, N.; Suematsu, Y.; Tsuneta, S.; Aoki, K.; Miyagawa, K.; Ichimoto, K.; Kobayashi, K.; Auchère, F.; Clasp Team

2014-10-01

The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is a VUV spectro-polarimeter optimized for measuring the linear polarization of the Lyman-α line (121.6 nm) to be launched in 2015 with NASA's sounding rocket (Ishikawa et al. 2011; Narukage et al. 2011; Kano et al. 2012; Kobayashi et al. 2012). With this experiment, we aim to (1) observe the scattering polarization in the Lyman-α line, (2) detect the Hanle effect, and (3) assess the magnetic fields in the upper chromosphere and transition region for the first time. The polarization measurement error consists of scale error δ a (error in amplitude of linear polarization), azimuth error Δφ (error in the direction of linear polarization), and spurious polarization ɛ (false linear polarization signals). The error ɛ should be suppressed below 0.1% in the Lyman-α core (121.567 nm ±0.02 nm), and 0.5% in the Lyman-α wing (121.567 nm ±0.05 nm), based on our scientific requirements shown in Table 2 of Kubo et al. (2014). From scientific justification, we adopt Δ φspectro-polarimeter features a continuously rotating MgF2 waveplate (Ishikawa et al. 2013), a dual-beam spectrograph with a spherical grating working also as a beam splitter, and two polarization analyzers (Bridou et al. 2011), which are mounted at 90 degree from each other to measure two orthogonal polarization simultaneously. For the optical layout of the CLASP instrument, see Figure 3 in Kubo et al. (2014). Considering the continuous rotation of the half-waveplate, the modulation efficiency is 0.64 both for Stokes Q and U. All the raw data are returned and demodulation (successive addition or subtraction of images) is done on the ground. We control the CLASP polarization performance in the following three steps. First, we evaluate the throughput and polarization properties of each optical component in the Lyman-α line, using the Ultraviolet Synchrotron ORbital Radiation Facility (UVSOR) at the Institute for Molecular Science. The second step

Storage-ring FEL for the vuv

International Nuclear Information System (INIS)

Peterson, J.M.; Bisognano, J.J.; Garren, A.A.; Halbach, K.; Kim, K.J.; Sah, R.C.

1984-09-01

A free-electron laser for the vuv operating in a storage ring requires an electron beam of high density and low energy spread and a short wavelength, narrow-gap undulator. These conditions tend to produce longitudinal and transverse beam instabilities, excessive beam growth through multiple intrabeam scattering, and a short gas-scattering lifetime. Passing the beam only occasionally through the undulator in a by-pass straight section, as proposed by Murphy and Pellegrini, allows operation in a high-gain, single-pass mode and a long gas-scattering lifetime. Several storage ring designs have been considered to see how best to satisfy the several requirements. Each features a by-pass, a low-emittance lattice, and built-in wigglers for enhanced damping to counteract the intra-beam scattering. 15 references, 3 figures, 2 tables

Atmospheric Measurements Laboratory (AML)

Data.gov (United States)

Federal Laboratory Consortium — The Atmospheric Measurements Laboratory (AML) is one of the nation's leading research facilities for understanding aerosols, clouds, and their interactions. The AML...

Uncooled Radiation Hard SiC Schottky VUV Detectors Capable of Single Photon Sensing, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — This project seeks to design, fabricate, characterize and commercialize very large area, uncooled and radiative hard 4H-SiC VUV detectors capable of near single...

EUV-VUV photochemistry in the upper atmospheres of Titan and the early Earth

Science.gov (United States)

Imanaka, H.; Smith, M. A.

2010-12-01

Titan, the organic-rich moon of Saturn, possesses a thick atmosphere of nitrogen, globally covered with organic haze layers. The recent Cassini’s INMS and CAPS observations clearly demonstrate the importance of complex organic chemistry in the ionosphere. EUV photon radiation is the major driving energy source there. Our previous laboratory study of the EUV-VUV photolysis of N2/CH4 gas mixtures demonstrates a unique role of nitrogen photoionization in the catalytic formation of complex hydrocarbons in Titan’s upper atmosphere (Imanaka and Smith, 2007, 2009). Such EUV photochemistry could also have played important roles in the formation of complex organic molecules in the ionosphere of the early Earth. It has been suggested that the early Earth atmosphere may have contained significant amount of reduced species (CH4, H2, and CO) (Kasting, 1990, Pavlov et al., 2001, Tian et al., 2005). Recent experimental study, using photon radiation at wavelengths longer than 110 nm, demonstrates that photochemical organic haze could have been generated from N2/CO2 atmospheres with trace amounts of CH4 or H2 (Trainer et al., 2006, Dewitt et al., 2009). However, possible EUV photochemical processes in the ionosphere are not well understood. We have investigated the effect of CO2 in the possible EUV photochemical processes in simulated reduced early Earth atmospheres. The EUV-VUV photochemistry using wavelength-tunable synchrotron light between 50 - 150 nm was investigated for gas mixtures of 13CO2/CH4 (= 96.7/3.3) and N2/13CO2/CH4 (= 90/6.7/3.3). The onsets of unsaturated hydrocarbon formation were observed at wavelengths shorter than the ionization potentials of CO2 and N2, respectively. This correlation indicates that CO2 can play a similar catalytic role to N2 in the formation of heavy organic species, which implies that EUV photochemistry might have significant impact on the photochemical generation of organic haze layers in the upper atmosphere of the early Earth.

Photofragmentation spectra of halogenated methanes in the VUV photon energy range

Energy Technology Data Exchange (ETDEWEB)

Cartoni, Antonella, E-mail: antonella.cartoni@uniroma1.it [Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza Università di Roma, P.le Aldo Moro 5, Roma 00185 (Italy); Bolognesi, Paola; Fainelli, Ettore; Avaldi, Lorenzo [CNR-IMIP, Area della Ricerca di Roma 1, Monterotondo Scalo (Rm) 00015 (Italy)

2014-05-14

In this paper an investigation of the photofragmentation of dihalomethanes CH{sub 2}X{sub 2} (X = F, Cl, Br, I) and chlorinated methanes (CH{sub n}Cl{sub 4−n} with n = 0–3) with VUV helium, neon, and argon discharge lamps is reported and the role played by the different halogen atoms is discussed. Halogenated methanes are a class of molecules used in several fields of chemistry and the study of their physical and chemical proprieties is of fundamental interest. In particular their photodissociation and photoionization are of great importance since the decomposition of these compounds in the atmosphere strongly affects the environment. The results of the present work show that the halogen-loss is the predominant fragmentation channel for these molecules in the VUV photon energy range and confirm their role as reservoir of chlorine, bromine, and iodine atoms in the atmosphere. Moreover, the results highlight the peculiar feature of CH{sub 2}F{sub 2} as a source of both fluorine and hydrogen atoms and the characteristic formation of I{sub 2}{sup +} and CH{sub 2}{sup +} ions from the photofragmentation of the CH{sub 2}I{sub 2} molecule.

Hydrothermal synthesis and luminescent properties of LnPO4:Tb,Bi (Ln=La,Gd) phosphors under UV/VUV excitation

International Nuclear Information System (INIS)

Wang Yuhua; Wu Chunfang; Wei Jie

2007-01-01

Monoclinic LnPO 4 :Tb,Bi (Ln=La,Gd) phosphors were prepared by hydrothermal reaction and their luminescent properties under ultraviolet (UV) and vacuum ultraviolet (VUV) excitation were investigated. LaPO 4 :Tb,Bi phosphor and GdPO 4 :Tb phosphor showed the strongest emission intensity under 254 and 147 nm excitation, respectively, because of the different energy transfer models. In UV region, Bi 3+ absorbed most energy then transferred to Tb 3+ , but in VUV region it was the host which absorbed most energy and transferred to Tb 3+

UV and VUV characteristics of (YGd)2O3:Eu phosphor particles prepared by spray pyrolysis from polymeric precursors

International Nuclear Information System (INIS)

Kim, E.J.; Kang, Y.C.; Park, H.D.; Ryu, S.K.

2003-01-01

Red-emitting (YGd) 2 O 3 :Eu phosphor particles, with high luminescence efficiency under vacuum ultraviolet (VUV) and ultraviolet (UV) excitation, were prepared by a large-scale spray pyrolysis process. To control the morphology of phosphor particles under severe preparation conditions, spray solution with polymeric precursors were introduced in spray pyrolysis. The prepared (YGd) 2 O 3 :Eu phosphor particles had spherical shape and filled morphology even after post-treatment irrespective of Gd/Y ratio. In the case of solution with polymeric precursors, long polymeric chains formed by esterification reaction in a hot tubular reactor; the droplets turned into viscous gel, which retarded the precipitation of nitrate salts and promoted the volume precipitation of droplets. The brightness of (YGd) 2 O 3 :Eu phosphor particles increased with increasing gadolinium content, and the Gd 2 O 3 :Eu phosphor had the highest luminescence intensity under UV and VUV excitation. The maximum peak intensity of Gd 2 O 3 :Eu phosphor particles under UV and VUV were 118 and 110% of the commercial Y 2 O 3 :Eu phosphor particles, respectively

A Cherenkov radiator for FEL-synchronized VUV-pulses at a linac-based FEL

NARCIS (Netherlands)

Goloviznin, V. V.; Oepts, D.; van der Wiel, M. J.

1997-01-01

A possible way to carry out two-color IR+VUV pump-probe experiments at linac-based FELs is proposed. The idea is to supply an FEL facility with a gas cell filled with helium or hydrogen, so that the electron beam, upon passage through the undulator, could be used to generate ultraviolet Cherenkov

A Cherenkov radiator for FEL-synchronized VUV-pulses at a linac-based FEL

NARCIS (Netherlands)

Goloviznin, V.V.; Oepts, W.; Wiel, van der M.J.

1997-01-01

A possible way to carry out two-color IR + VUV pump-probe experiments at linac-based FELs is proposed. The idea is to supply an FEL facility with a gas cell filled with helium or hydrogen, so that the electron beam, upon passage through the undulator, could be used to generate ultraviolet Cherenkov

172 nm excimer VUV-triggered photodegradation and micropatterning of aminosilane films

International Nuclear Information System (INIS)

Elsner, Christian; Naumov, Sergej; Zajadacz, Joachim; Buchmeiser, Michael R.

2009-01-01

Emission from Xe 2 * excimers exhibiting photon energies between 7 and 10 eV can be used to induce strong surface modification effects on polymeric materials in the top 100 nm layer. In order to identify suitable monomers for this VUV-based process, the photodegradation mechanism of different organosilanes of the general structure R-CH 2 -Si(OCH 3 ) 3 was elucidated by quantum chemical calculations. Herein, the photodegradation of 3-aminopropyltrimethoxysilane films by the use of a 172 nm excimer lamp under different irradiation conditions is described and completed by micropatterning experiments. The presence of 1000-5000 ppm oxygen was found to promote the transformation process to an inorganic-like surface. The films obtained were analyzed by X-ray photoelectron spectroscopy, contact angle measurements and fluorescence microscopy after covalent attachment of a fluorescent dye to the remaining amino groups. Complementary, silver staining was used to visualize photopatterning.

Digital low level RF control system for the DESY TTF VUV-FEL Linac

International Nuclear Information System (INIS)

Ayvazyan, V.; Choroba, S.; Matyushin, A.; Moeller, G.; Petrosyan, G.; Rehlich, K.; Simrock, S.N.; Vetrov, P.

2005-01-01

In the RF system for the Vacuum Ultraviolet Free Electron Laser (VUV-FEL) Linac each klystron supplies RF power to up to 32 cavities. The superconducting cavities are operated in pulsed mode and high accelerating gradients close to the performance limit. The RF control of the cavity fields to the level of 10 -4 for amplitude and 0.1 degree for phase however presents a significant technical challenge due to the narrow bandwidth of the cavities which results in high sensitivity to perturbations of the resonance frequency by mechanical vibrations (microphonics) and Lorenz force detuning. The VUV-FEL Linac RF control system employs a completely digital feedback system to provide flexibility in the control algorithms, precise calibration of the accelerating field vector-sum, and extensive diagnostics and exception handling capabilities. The RF control algorithm is implemented in DSP (Digital Signal Processor) firmware and DOOCS (Distributed Object Oriented Control System) servers. The RF control system design objectives are discussed. Hardware and software design of the DSP based RF control are presented. (orig.)

Digital low level RF control system for the DESY TTF VUV-FEL Linac

Energy Technology Data Exchange (ETDEWEB)

Ayvazyan, V.; Choroba, S.; Matyushin, A.; Moeller, G.; Petrosyan, G.; Rehlich, K.; Simrock, S.N.; Vetrov, P.

2005-07-01

In the RF system for the Vacuum Ultraviolet Free Electron Laser (VUV-FEL) Linac each klystron supplies RF power to up to 32 cavities. The superconducting cavities are operated in pulsed mode and high accelerating gradients close to the performance limit. The RF control of the cavity fields to the level of 10{sup -4} for amplitude and 0.1 degree for phase however presents a significant technical challenge due to the narrow bandwidth of the cavities which results in high sensitivity to perturbations of the resonance frequency by mechanical vibrations (microphonics) and Lorenz force detuning. The VUV-FEL Linac RF control system employs a completely digital feedback system to provide flexibility in the control algorithms, precise calibration of the accelerating field vector-sum, and extensive diagnostics and exception handling capabilities. The RF control algorithm is implemented in DSP (Digital Signal Processor) firmware and DOOCS (Distributed Object Oriented Control System) servers. The RF control system design objectives are discussed. Hardware and software design of the DSP based RF control are presented. (orig.)

Luminescence mechanism in doubly Gd, Nd-codoped fluoride crystals for VUV scintillators

Czech Academy of Sciences Publication Activity Database

Pejchal, Jan; Fukuda, K.; Babin, Vladimir; Kurosawa, S.; Yokota, Y.; Yoshikawa, A.; Nikl, Martin

2016-01-01

Roč. 169, Jan (2016), s. 682-689 ISSN 0022-2313. [International Conference on Luminescence and Optical Spectroscopy of Condensed Matter /17./. Wroclaw, 13.07.2014-18.07.2014] R&D Projects: GA MŠk(CZ) LH14266 Institutional support: RVO:68378271 Keywords : barium –lutetium–yttrium fluoride * lutetium fluoride * scintillator * VUV luminescence Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.686, year: 2016

Combustion synthesis and optical properties of Oxy-borate phosphors YCa4O(BO3)3:RE3+ (RE = Eu3+, Tb3+) under UV, VUV excitation

International Nuclear Information System (INIS)

Ingle, J.T.; Gawande, A.B.; Sonekar, R.P.; Omanwar, S.K.; Wang, Yuhua; Zhao, Lei

2014-01-01

Graphical abstract: VUV Photoluminescence of YCa 4 O(BO 3 ) 3 : Eu 3+ and YCa 4 O(BO 3 ) 3 : Tb 3+ for PDPs applications. Highlights: • Inorganic Oxy-borate phosphors YCa 4 O(BO 3 ) 3 :Eu 3+ ,Tb 3+ was synthesized by novel solution combustion synthesis. • This single host produces efficient and intense Red and Green color for display applications. • Good agreement with CIE co-ordinates as prescribes by NTCL, for flat panel, PDP display color. • Synthesized materials were characterized using powder XRD, FE-SEM, UV and VUV Spectophotometer. -- Abstract: The inorganic Oxy-borate host phosphors YCa 4 O(BO 3 ) 3 :RE 3+ (RE = Eu 3+ ,Tb 3+ ) were synthesized by a novel solution combustion technique. The synthesis is based on the exothermic reaction between the fuel (Urea) and Oxidizer (Ammonium nitrate). The heat generated in reaction is use for auto combustion of precursors. The structures of the prepared samples were confirmed by powder XRD technique. The photoluminescence properties of the powder samples were investigated under UV and VUV excitation; “The phosphor YCa 4 O(BO 3 ) 3 :Eu 3+ and YCa 4 O(BO 3 ) 3 :Tb 3+ shows strong absorption in UV and VUV region and exhibits intense red and green emission upon excited by 254 nm UV and 147 nm VUV radiation”

FORMATION OF S-BEARING SPECIES BY VUV/EUV IRRADIATION OF H2S-CONTAINING ICE MIXTURES: PHOTON ENERGY AND CARBON SOURCE EFFECTS

International Nuclear Information System (INIS)

Chen, Y.-J.; Juang, K.-J.; Qiu, J.-M.; Chu, C.-C.; Yih, T.-S.; Nuevo, M.; Jiménez-Escobar, A.; Muñoz Caro, G. M.; Wu, C.-Y. R.; Fung, H.-S.; Ip, W.-H.

2015-01-01

Carbonyl sulfide (OCS) is a key molecule in astrobiology that acts as a catalyst in peptide synthesis by coupling amino acids. Experimental studies suggest that hydrogen sulfide (H 2 S), a precursor of OCS, could be present in astrophysical environments. In the present study, we used a microwave-discharge hydrogen-flow lamp, simulating the interstellar UV field, and a monochromatic synchrotron light beam to irradiate CO:H 2 S and CO 2 :H 2 S ice mixtures at 14 K with vacuum ultraviolet (VUV) or extreme ultraviolet (EUV) photons in order to study the effect of the photon energy and carbon source on the formation mechanisms and production yields of S-containing products (CS 2 , OCS, SO 2 , etc.). Results show that (1) the photo-induced OCS production efficiency in CO:H 2 S ice mixtures is higher than that of CO 2 :H 2 S ice mixtures; (2) a lower concentration of H 2 S enhances the production efficiency of OCS in both ice mixtures; and (3) the formation pathways of CS 2 differ significantly upon VUV and EUV irradiations. Furthermore, CS 2 was produced only after VUV photoprocessing of CO:H 2 S ices, while the VUV-induced production of SO 2 occurred only in CO 2 :H 2 S ice mixtures. More generally, the production yields of OCS, H 2 S 2 , and CS 2 were studied as a function of the irradiation photon energy. Heavy S-bearing compounds were also observed using mass spectrometry during the warm-up of VUV/EUV-irradiated CO:H 2 S ice mixtures. The presence of S-polymers in dust grains may account for the missing sulfur in dense clouds and circumstellar environments

VUV Spectroscopy of the Sun as a Star

Science.gov (United States)

Kankelborg, Charles; Philip, Judge; Winebarger, Amy R.; Kobayashi, Ken; Smart, Roy

2017-08-01

We describe a new sounding rocket mission to obtain the first high resolution, high quality VUV (100-200 nm) spectrum of the Sun-as-a-star. Our immediate science goal is to understand better the processes of chromospheric and coronal heating. HST data exist for a dozen or so Sun-like stars of a quality already beyond our ability to construct a comparable sun-as-a-star UV spectrum. The solar spectrum we obtain will enable us to understand the nature of magnetic energy dissipation as a Sun-like star evolves, and the dependence of magnetic activity on stellar mass and metallicity. This poster presents the instrument design, scientific prospects, and broader impacts of the proposed mission.

Degradation mechanisms of the blue-emitting phosphor BaMgAl{sub 10}O{sub 17}:Eu{sup 2+} under baking and VUV-irradiating treatments

Energy Technology Data Exchange (ETDEWEB)

Zhang Shuxiu E-mail: shuxiu_zhang@dyden.co.jp; Kono, Toshihiko; Ito, Akira; Yasaka, Taketo; Uchiike, Heiju

2004-01-01

The luminescent properties of an Eu{sup 2+}-activated hexagonal aluminate, BaMgAl{sub 10}O{sub 17} (BAM), were studied under 147- and 254-nm excitations. The BAM samples were thermally treated by baking and then irradiated in vacuum ultraviolet (VUV) rays. The results show that the emission efficiency of Eu{sup 2+} in BAM under 147-nm excitation degraded seriously after baking or VUV-irradiating treatments, while no significant degradation was observed under 254-nm excitation. The degree of degradation depended on the excitation wavelength, and the absorption edge of the BAM host was suggested to be close to 175 nm (7.2 eV). The differences between the thermal-induced and the VUV-irradiation-induced degradations, and their mechanisms are discussed for the color plasma display applications.

VUV photoemission studies of candidate Large Hadron Collider vacuum chamber materials

CERN Document Server

Cimino, R; Baglin, V

1999-01-01

In the context of future accelerators and, in particular, the beam vacuum of the Large Hadron Collider (LHC), a 27 km circumference proton collider to be built at CERN, VUV synchrotron radiation (SR) has been used to study both qualitatively and quantitatively candidate vacuum chamber materials. Emphasis is given to show that angle and energy resolved photoemission is an extremely powerful tool to address important issues relevant to the LHC, such as the emission of electrons that contributes to the creation of an electron cloud which may cause serious beam instabilities and unmanageable heat loads on the cryogenic system. Here we present not only the measured photoelectron yields from the proposed materials, prepared on an industrial scale, but also the energy and in some cases the angular dependence of the emitted electrons when excited with either a white light (WL) spectrum, simulating that in the arcs of the LHC, or monochromatic light in the photon energy range of interest. The effects on the materials ...

FORMATION OF S-BEARING SPECIES BY VUV/EUV IRRADIATION OF H{sub 2}S-CONTAINING ICE MIXTURES: PHOTON ENERGY AND CARBON SOURCE EFFECTS

Energy Technology Data Exchange (ETDEWEB)

Chen, Y.-J.; Juang, K.-J.; Qiu, J.-M.; Chu, C.-C.; Yih, T.-S. [Department of Physics, National Central University, Jhongli City, Taoyuan County 32054, Taiwan (China); Nuevo, M. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Jiménez-Escobar, A.; Muñoz Caro, G. M. [Centro de Astrobiología, INTA-CSIC, Torrejón de Ardoz, E-28850 Madrid (Spain); Wu, C.-Y. R. [Space Sciences Center and Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089-1341 (United States); Fung, H.-S. [National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan (China); Ip, W.-H. [Graduate Institute of Astronomy, National Central University, Jhongli City, Taoyuan County 32049, Taiwan (China)

2015-01-10

Carbonyl sulfide (OCS) is a key molecule in astrobiology that acts as a catalyst in peptide synthesis by coupling amino acids. Experimental studies suggest that hydrogen sulfide (H{sub 2}S), a precursor of OCS, could be present in astrophysical environments. In the present study, we used a microwave-discharge hydrogen-flow lamp, simulating the interstellar UV field, and a monochromatic synchrotron light beam to irradiate CO:H{sub 2}S and CO{sub 2}:H{sub 2}S ice mixtures at 14 K with vacuum ultraviolet (VUV) or extreme ultraviolet (EUV) photons in order to study the effect of the photon energy and carbon source on the formation mechanisms and production yields of S-containing products (CS{sub 2}, OCS, SO{sub 2}, etc.). Results show that (1) the photo-induced OCS production efficiency in CO:H{sub 2}S ice mixtures is higher than that of CO{sub 2}:H{sub 2}S ice mixtures; (2) a lower concentration of H{sub 2}S enhances the production efficiency of OCS in both ice mixtures; and (3) the formation pathways of CS{sub 2} differ significantly upon VUV and EUV irradiations. Furthermore, CS{sub 2} was produced only after VUV photoprocessing of CO:H{sub 2}S ices, while the VUV-induced production of SO{sub 2} occurred only in CO{sub 2}:H{sub 2}S ice mixtures. More generally, the production yields of OCS, H{sub 2}S{sub 2}, and CS{sub 2} were studied as a function of the irradiation photon energy. Heavy S-bearing compounds were also observed using mass spectrometry during the warm-up of VUV/EUV-irradiated CO:H{sub 2}S ice mixtures. The presence of S-polymers in dust grains may account for the missing sulfur in dense clouds and circumstellar environments.

A new instrument of VUV laser desorption/ionization mass spectrometry imaging with micrometer spatial resolution and low level of molecular fragmentation.

Science.gov (United States)

Wang, Jia; Liu, Feng; Mo, Yuxiang; Wang, Zhaoying; Zhang, Sichun; Zhang, Xinrong

2017-11-01

Mass spectrometry imaging (MSI) has important applications in material research, biology, and medicine. The MSI method based on UV laser desorption/ionization (UVLDI) can obtain images of intact samples, but has a high level of molecular fragmentation. In this work, we report a new MSI instrument that uses a VUV laser (125.3 nm) as a desorption/ionization source to exploit its advantages of high single photon energy and small focus size. The new instrument was tested by the mass spectra of Nile red and FGB (Fibrinogen beta chain) samples and mass spectrometric images of a fly brain section. For the tested samples, the VUVDI method offers lower levels of molecular fragmentations and higher sensitivities than those of the UVLDI method and second ion mass spectrometry imaging method using a Bi 3 + beam. The ablation crater produced by the focused VUV laser on a quartz plate has an area of 10 μm 2 . The VUV laser is prepared based on the four-wave mixing method using three collimated laser beams and a heated Hg cell.

A new instrument of VUV laser desorption/ionization mass spectrometry imaging with micrometer spatial resolution and low level of molecular fragmentation

Science.gov (United States)

Wang, Jia; Liu, Feng; Mo, Yuxiang; Wang, Zhaoying; Zhang, Sichun; Zhang, Xinrong

2017-11-01

Mass spectrometry imaging (MSI) has important applications in material research, biology, and medicine. The MSI method based on UV laser desorption/ionization (UVLDI) can obtain images of intact samples, but has a high level of molecular fragmentation. In this work, we report a new MSI instrument that uses a VUV laser (125.3 nm) as a desorption/ionization source to exploit its advantages of high single photon energy and small focus size. The new instrument was tested by the mass spectra of Nile red and FGB (Fibrinogen beta chain) samples and mass spectrometric images of a fly brain section. For the tested samples, the VUVDI method offers lower levels of molecular fragmentations and higher sensitivities than those of the UVLDI method and second ion mass spectrometry imaging method using a Bi3+ beam. The ablation crater produced by the focused VUV laser on a quartz plate has an area of 10 μm2. The VUV laser is prepared based on the four-wave mixing method using three collimated laser beams and a heated Hg cell.

Clearance Laboratory - Capability and measurement sensitivity

Energy Technology Data Exchange (ETDEWEB)

Hedemann Jensen, P.; Lauridsen, B.; Silva, J.; Soegaard-Hansen, J.; Warming, L.

2005-08-01

A new low-level Clearance Laboratory has been built at the Risoe-site. Building materials with a low content of naturally occurring radionuclides have been used. To minimize transport of radon gas from soil into the laboratory the foundation has been supplied with a membrane. The laboratory has been equipped with two high-efficiency germanium detectors. These detectors will be used for clearance measurements on the predicted amount of 15,000 - 18,000 tonnes of non-active or nearly non-active materials, which will originate from the decommissioning of all the nuclear facilities at the Risoe-site. They will be used also for clearance measurements on buildings and land. Objects and materials to be measured for clearance are placed on a rotation table that can carry up to one tonne and can rotate once a minute to simulate some averaging of inhomogeneously distributed activity. Sensitivity and background measurements reveal that measuring times of 20 - 50 minutes would normally be sufficient to detect radionuclide concentrations of only a small fraction of the nuclide-specific clearance levels with a sufficiently low uncertainty. Probability calculations of the measurement capacity of the Clearance Laboratory indicate that the mean value of the total measuring time for all materials that potentially can be cleared would be 13 years with a 95% probability of being less than 25 years. The mean value of the annual amount of materials that can be measured in the laboratory is 600 tonnes with a 95% probability of being less than 1,200 tonnes. If needed, there is room for additional measuring systems to increase the capacity of the laboratory. (au)

Clearance Laboratory - Capability and measurement sensitivity

International Nuclear Information System (INIS)

Hedemann Jensen, P.; Lauridsen, B.; Silva, J.; Soegaard-Hansen, J.; Warming, L.

2005-09-01

A new low-level Clearance Laboratory has been built at the Risoe-site. Building materials with a low content of naturally occurring radionuclides have been used. To minimize transport of radon gas from soil into the laboratory the foundation has been supplied with a membrane. The laboratory has been equipped with two high-efficiency germanium detectors. These detectors will be used for clearance measurements on the predicted amount of 15,000 - 18,000 tonnes of non-active or nearly non-active materials, which will originate from the decommissioning of all the nuclear facilities at the Risoe-site. They will be used also for clearance measurements on buildings and land. Objects and materials to be measured for clearance are placed on a rotation table that can carry up to one tonne and can rotate once a minute to simulate some averaging of inhomogeneously distributed activity. Sensitivity and background measurements reveal that measuring times of 20 - 50 minutes would normally be sufficient to detect radionuclide concentrations of only a small fraction of the nuclide-specific clearance levels with a sufficiently low uncertainty. Probability calculations of the measurement capacity of the Clearance Laboratory indicate that the mean value of the total measuring time for all materials that potentially can be cleared would be 13 years with a 95% probability of being less than 25 years. The mean value of the annual amount of materials that can be measured in the laboratory is 600 tonnes with a 95% probability of being less than 1,200 tonnes. If needed, there is room for additional measuring systems to increase the capacity of the laboratory. (au)

VUV photoionization and dissociative photoionization of the prebiotic molecule acetyl cyanide: Theory and experiment

International Nuclear Information System (INIS)

Bellili, A.; Hochlaf, M.; Schwell, M.; Bénilan, Y.; Fray, N.; Gazeau, M.-C.; Mogren Al-Mogren, M.; Guillemin, J.-C.; Poisson, L.

2014-01-01

The present combined theoretical and experimental investigation concerns the single photoionization of gas-phase acetyl cyanide and the fragmentation pathways of the resulting cation. Acetyl cyanide (AC) is inspired from both the chemistry of cyanoacetylene and the Strecker reaction which are thought to be at the origin of medium sized prebiotic molecules in the interstellar medium. AC can be formed by reaction from cyanoacetylene and water but also from acetaldehyde and HCN or the corresponding radicals. In view of the interpretation of vacuum ultraviolet (VUV) experimental data obtained using synchrotron radiation, we explored the ground potential energy surface (PES) of acetyl cyanide and of its cation using standard and recently implemented explicitly correlated methodologies. Our PES covers the regions of tautomerism (between keto and enol forms) and of the lowest fragmentation channels. This allowed us to deduce accurate thermochemical data for this astrobiologically relevant molecule. Unimolecular decomposition of the AC cation turns out to be very complex. The implications for the evolution of prebiotic molecules under VUV irradiation are discussed

VUV photoionization and dissociative photoionization of the prebiotic molecule acetyl cyanide: Theory and experiment

Energy Technology Data Exchange (ETDEWEB)

Bellili, A.; Hochlaf, M., E-mail: hochlaf@univ-mlv.fr, E-mail: martin.schwell@lisa.u-pec.fr [Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, Université Paris-Est, 5 bd Descartes, 77454 Marne-la-Vallée (France); Schwell, M., E-mail: hochlaf@univ-mlv.fr, E-mail: martin.schwell@lisa.u-pec.fr; Bénilan, Y.; Fray, N.; Gazeau, M.-C. [Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR 7583 CNRS, Institut Pierre et Simon Laplace, Universités Paris-Est Créteil et Paris Diderot, 61 Avenue du Général de Gaulle, 94010 Créteil (France); Mogren Al-Mogren, M. [Chemistry Department, Faculty of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Guillemin, J.-C. [Institut des Sciences Chimiques de Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7 (France); Poisson, L. [Laboratoire Francis Perrin, CNRS URA 2453, CEA, IRAMIS, Laboratoire Interactions Dynamique et Lasers, Bât 522, F-91191 Gif/Yvette (France)

2014-10-07

The present combined theoretical and experimental investigation concerns the single photoionization of gas-phase acetyl cyanide and the fragmentation pathways of the resulting cation. Acetyl cyanide (AC) is inspired from both the chemistry of cyanoacetylene and the Strecker reaction which are thought to be at the origin of medium sized prebiotic molecules in the interstellar medium. AC can be formed by reaction from cyanoacetylene and water but also from acetaldehyde and HCN or the corresponding radicals. In view of the interpretation of vacuum ultraviolet (VUV) experimental data obtained using synchrotron radiation, we explored the ground potential energy surface (PES) of acetyl cyanide and of its cation using standard and recently implemented explicitly correlated methodologies. Our PES covers the regions of tautomerism (between keto and enol forms) and of the lowest fragmentation channels. This allowed us to deduce accurate thermochemical data for this astrobiologically relevant molecule. Unimolecular decomposition of the AC cation turns out to be very complex. The implications for the evolution of prebiotic molecules under VUV irradiation are discussed.

Experience with a high-brightness storage ring: the NSLS 750 MeV vuv ring

International Nuclear Information System (INIS)

Galayda, J.

1984-01-01

The NSLS vuv ring is the first implementation of the proposals of R. Chasman and G.K. Green for a synchrotron radiation source with enhanced brightness: its lattice is a series of achromatic bends with two zero-gradient dipoles each, giving small damped emittance; and these bends are connected by straight sections with zero dispersion to accommodate wigglers and undulators without degrading the radiation damping properties of the ring. The virtues of the Chasman-Green lattice, its small betatron and synchrotron emittances, may be understood with some generality; e.g. the electron γm 0 c 2 energy and the number of achromatic bends M sets a lower limit on the betatron emittance of e/sub x/ > 7.7 x 10 -13 γ 2 /M meter-radians. There is strong interest in extrapolation of this type of lattice to 6 GeV and to 32 achromatic bends. The subject of this report is the progress toward achieving performance in the vuv ring limited by the radiation damping parameters optimized in its design. 14 refs., 4 figs., 1 tab

A new broadly tunable (7.4-10.2 eV) laser based VUV light source and its first application to aerosol mass spectrometry

Science.gov (United States)

Hanna, S. J.; Campuzano-Jost, P.; Simpson, E. A.; Robb, D. B.; Burak, I.; Blades, M. W.; Hepburn, J. W.; Bertram, A. K.

2009-01-01

A laser based vacuum ultraviolet (VUV) light source using resonance enhanced four wave difference mixing in xenon gas was developed for near threshold ionization of organics in atmospheric aerosol particles. The source delivers high intensity pulses of VUV light (in the range of 1010 to 1013 photons/pulse depending on wavelength, 5 ns FWHM) with a continuously tunable wavelength from 122 nm (10.2 eV) to 168 nm (7.4 eV)E The setup allows for tight (caffeine aerosols vaporized by a pulsed CO2 laser in an ion trap mass spectrometer. Mass spectra from single particles down to 300 nm in diameter were collected. Excellent signal to noise characteristics for these small particles give a caffeine detection limit of 8 × 105 molecules which is equivalent to a single 75 nm aerosol, or approximately 1.5% of a 300 nm particleE The appearance energy of caffeine originating from the aerosol was also measured and found to be 7.91 ± 0.05 eV, in good agreement with literature values.

Quality assurance handbook for measurement laboratories

International Nuclear Information System (INIS)

Delvin, W.L.

1984-10-01

This handbook provides guidance in the application of quality assurance to measurement activities. It is intended to help those persons making measurements in applying quality assurance to their work activities by showing how laboratory practices and quality assurance requirements are integrated to provide control within those activities. The use of the guidance found in this handbook should help provide consistency in the interpretation of quality assurance requirements across all types of measurement laboratories. This handbook also can assist quality assurance personnel in understanding the relationships between laboratory practices and quality assurance requirements. The handbook is composed of three chapters and several appendices. Basic guidance is provided by the three chapters. In Chapter 1, the role of quality assurance in obtaining quality data and the importance of such data are discussed. Chapter 2 presents the elements of laboratory quality assurance in terms of practices that can be used in controlling work activities to assure the acquisition of quality data. Chapter 3 discusses the implementation of laboratory quality assurance. The appendices provide supplemental information to give the users a better understanding of the following: what is quality assurance; why quality assurance is required; where quality assurance requirements come from; how those requirements are interpreted for application to laboratory operations; how the elements of laboratory quality assurance relate to various laboratory activities; and how a quality assurance program can be developed

The nuclear isomer transition in Thorium-229. Search for the VUV photon

Energy Technology Data Exchange (ETDEWEB)

Stellmer, Simon [TU Wien (Austria). Atominstitut; VCQ, Vienna (Austria); Schreitl, Matthias; Schumm, Thorsten [TU Wien (Austria). Atominstitut; Yoshimura, Koji [Okayama University (Japan)

2015-07-01

The isotope {sup 229}Th is believed to possess a low-lying nuclear excitation, at an energy of about 7.8(5) eV, corresponding to a wavelength of 160(10) nm. Convincing direct evidence of the existence of this state, for instance by observation of its excitation or decay, is still pending. Optical excitation of the isomer state is an exceptional challenge, as the required wavelength is not known, the transition is believed to be extremely narrow, and the choice of suitable lasers is limited. Instead, we use synchrotron radiation at 29 keV to populate the second excited state, which then decays into the desired isomer state. This state proceeds further into the ground state under emission of the much sought-after VUV photon. This photon is detected in a spectrometer. The measurements are performed at the SPring-8 facility in Japan; we will report on the latest status of the experiment.

Ultrawide spectral broadening and compression of single extremely short pulses in the visible, uv-vuv, and middle infrared by high-order stimulated Raman scattering

International Nuclear Information System (INIS)

Kalosha, V. P.; Herrmann, J.

2003-01-01

We present the results of a comprehensive analytical and numerical study of ultrawide spectral broadening and compression of isolated extremely short visible, uv-vuv and middle infrared (MIR) pulses by high-order stimulated Raman scattering in hollow waveguides. Spectral and temporal characteristics of the output pulses and the mechanism of pulse compression using dispersion of the gas filling and output glass window are investigated without the slowly varying envelope approximation. Physical limitations due to phase mismatch, velocity walk off, and pump-pulse depletion as well as improvements through the use of pump-pulse sequences and dispersion control are studied. It is shown that phase-locked pulses as short as ∼2 fs in the visible and uv-vuv, and 6.5 fs in the MIR can be generated by coherent scattering in impulsively excited Raman media without the necessity of external phase control. Using pump-pulse sequences, shortest durations in the range of about 1 fs for visible and uv-vuv probe pulses are predicted

Statistical properties of SASE FEL radiation: experimental results from the VUV FEL at the TESLA test facility at DESY

International Nuclear Information System (INIS)

Yurkov, M.V.

2002-01-01

This paper presents an experimental study of the statistical properties of the radiation from a SASE FEL. The experiments were performed at the TESLA Test Facility VUV SASE FEL at DESY operating in a high-gain linear regime with a gain of about 10 6 . It is shown that fluctuations of the output radiation energy follows a gamma-distribution. We also measured for the first time the probability distribution of SASE radiation energy after a narrow-band monochromator. The experimental results are in good agreement with theoretical predictions, the energy fluctuations after the monochromator follow a negative exponential distribution

Enhancement of VUV emission from a coaxial xenon excimer ultraviolet lamp driven by distorted bipolar square voltages

Energy Technology Data Exchange (ETDEWEB)

Jou, S.Y.; Hung, C.T.; Chiu, Y.M.; Wu, J.S. [Department of Mechanical Engineering, National Chiao Tung University, Hsinchu (China); Wei, B.Y. [High-Efficiency Gas Discharge Lamps Group, Material and Chemical Research Laboratories, Hsinchu (China)

2011-12-15

Enhancement of vacuum UV emission (172 nm VUV) from a coaxial xenon excimer UV lamp (EUV) driven by distorted 50 kHz bipolar square voltages, as compared to that by sinusoidal voltages, is investigated numerically in this paper. A self-consistent radial one-dimensional fluid model, taking into consideration non-local electron energy balance, is employed to simulate the discharge physics and chemistry. The discharge is divided into two three-period portions; these include: the pre-discharge, the discharge (most intense at 172 nm VUV emission) and the post-discharge periods. The results show that the efficiency of VUV emission using the distorted bipolar square voltages is much greater than when using sinusoidal voltages; this is attributed to two major mechanisms. The first is the much larger rate of change of the voltage in bipolar square voltages, in which only the electrons can efficiently absorb the power in a very short period of time. Energetic electrons then generate a higher concentration of metastable (and also excited dimer) xenon that is distributed more uniformly across the gap, for a longer period of time during the discharge process. The second is the comparably smaller amount of ''wasted'' power deposition by Xe{sup +}{sub 2} in the post-discharge period, as driven by distorted bipolar square voltages, because of the nearly vanishing gap voltage caused by the shielding effect resulting from accumulated charges on both dielectric surfaces (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

VUV photoionization cross sections of HO2, H2O2, and H2CO.

Science.gov (United States)

Dodson, Leah G; Shen, Linhan; Savee, John D; Eddingsaas, Nathan C; Welz, Oliver; Taatjes, Craig A; Osborn, David L; Sander, Stanley P; Okumura, Mitchio

2015-02-26

The absolute vacuum ultraviolet (VUV) photoionization spectra of the hydroperoxyl radical (HO2), hydrogen peroxide (H2O2), and formaldehyde (H2CO) have been measured from their first ionization thresholds to 12.008 eV. HO2, H2O2, and H2CO were generated from the oxidation of methanol initiated by pulsed-laser-photolysis of Cl2 in a low-pressure slow flow reactor. Reactants, intermediates, and products were detected by time-resolved multiplexed synchrotron photoionization mass spectrometry. Absolute concentrations were obtained from the time-dependent photoion signals by modeling the kinetics of the methanol oxidation chemistry. Photoionization cross sections were determined at several photon energies relative to the cross section of methanol, which was in turn determined relative to that of propene. These measurements were used to place relative photoionization spectra of HO2, H2O2, and H2CO on an absolute scale, resulting in absolute photoionization spectra.

Laboratory Spectroscopy of Large Carbon Molecules and Ions in Support of Space Missions. A New Generation of Laboratory & Space Studies

Science.gov (United States)

Salama, Farid; Tan, Xiaofeng; Cami, Jan; Biennier, Ludovic; Remy, Jerome

2006-01-01

Polycyclic Aromatic Hydrocarbons (PAHs) are an important and ubiquitous component of carbon-bearing materials in space. A long-standing and major challenge for laboratory astrophysics has been to measure the spectra of large carbon molecules in laboratory environments that mimic (in a realistic way) the physical conditions that are associated with the interstellar emission and absorption regions [1]. This objective has been identified as one of the critical Laboratory Astrophysics objectives to optimize the data return from space missions [2]. An extensive laboratory program has been developed to assess the properties of PAHs in such environments and to describe how they influence the radiation and energy balance in space. We present and discuss the gas-phase electronic absorption spectra of neutral and ionized PAHs measured in the UV-Visible-NIR range in astrophysically relevant environments and discuss the implications for astrophysics [1]. The harsh physical conditions of the interstellar medium characterized by a low temperature, an absence of collisions and strong VUV radiation fields - have been simulated in the laboratory by associating a pulsed cavity ringdown spectrometer (CRDS) with a supersonic slit jet seeded with PAHs and an ionizing, penning-type, electronic discharge. We have measured for the {\\it first time} the spectra of a series of neutral [3,4] and ionized [5,6] interstellar PAHs analogs in the laboratory. An effort has also been attempted to quantify the mechanisms of ion and carbon nanoparticles production in the free jet expansion and to model our simulation of the diffuse interstellar medium in the laboratory [7]. These experiments provide {\\it unique} information on the spectra of free, large carbon-containing molecules and ions in the gas phase. We are now, for the first time, in the position to directly compare laboratory spectral data on free, cold, PAH ions and carbon nano-sized carbon particles with astronomical observations in the

Demonstration of resonant photopumping of Mo VII by Mo XII for a VUV laser near 600 Angstrom

International Nuclear Information System (INIS)

Ilcisin, K.J.; Aumayr, F.; Schwob, J.L.; Suckewer, S.

1993-09-01

We present data of experiments on the resonant photopumping of Mo VII by Mo XII as a method of generating a coherent VUV source near 600 angstrom. The experiment is based on a scheme proposed by Feldman and Reader in which the 4p 6 -- 4p 5 6s transition in Mo VII in resonantly photopumped by the 5s 2 S 1/2 -- 4p 2 P 1/2 transition in Mo XII. Results of the laser produced plasma experiments show the successful enhancement of the population of the Mo VII 4p 5 6s upper lasing level when pumped by an adjacent Mo VII plasma. No enhancement was seen in a control experiment where the Mo VII plasma was pumped by a Zr X plasma. Improvements of the intensity of the Mo XII pump source, achieved using an additional pump laser, lead to the generation of a population inversion for the VUV transition

Degradation of Solar Array Components in a Combined UV/VUV High Temperature Test Environment

Directory of Open Access Journals (Sweden)

Nömayr Christel

2017-01-01

A design verification test under UV/VUV conditions of sun exposed materials and technologies on component level is presented which forms part of the overall verification and qualification of the solar array design of the MTM and MPO. The test concentrates on the self-contamination aspects and the resulting performance losses of the solar array under high intensity and elevated temperature environment representative for the photovoltaic assembly (PVA.

Handbook of laboratory health and safety measures

International Nuclear Information System (INIS)

Pal, S.B.

1985-01-01

The application of radioactive isotopes and various scientific instruments based on different ionizing and non-ionizing radiation have brought new safety problems to laboratory workers today. Therefore, there is a need to revise present knowledge of safety measures to deal with new hazards, thus broadening the outlook towards health and safety measures for contemporary laboratory staff. This handbook presents a series of articles on current knowledge regarding laboratory safety

VUV emission spectroscopy diagnostics of a 14 GHz ECR negative hydrogen ion source

Energy Technology Data Exchange (ETDEWEB)

Tamura, R., E-mail: duo0364@mail4.doshisha.ac.jp; Ichikawa, T.; Kasuya, T.; Wada, M. [Graduate School of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0394 (Japan); Nishiura, M. [Graduate School of Frontier Sciences The University of Tokyo, Kashiwara, Chiba 277-8561 (Japan); Shimozuma, T. [National lnstitute for Fusion Science, Toki, Gifu 509-5292 (Japan)

2015-04-08

Vacuum Ultra Violet(VUV) emission from a 4 cm diameter 2 cm long compact ion source excited by 14 GHz microwave has been investigated. Intensity ratio of band spectrum emission near Ly-α to Ly-α line spectrum is determined from the measured spectrum. which shows preferential excitation of molecules near the entrance of microwave input power. The ratio does not depend strongly upon pressure nor the input microwave power when the intensity is integrated over the volume of the plasma. The spatial distribution of the spectrum intensity ratio exhibits concentrations near microwave inlet and the opposite side where the microwave matching structure is located. The ratio at these peripheral regions is about two times as high as that of the central region. The ratio increased in proportion to the ion source pressure up to about 3.0 Pa, indicating efficient production of high energy electrons by ECR up to this pressure.

VUV Spectroscopy in DIII-D Divertor

International Nuclear Information System (INIS)

Alkesh Punjabi; Nelson Jalufka

2004-01-01

The research carried out on this grant was motivated by the high power emission from the CIV doublet at 155 nm in the DIII-D divertor and to study the characteristics of the radiative divertor. The radiative divertor is designed to reduce the heat load to the target plates of the divertor by reducing the energy in the divertor plasma using upstream scrape-off-layer (SOL) radiation. In some cases, particularly in Partially Detached Divertor (PDD) operations, this emission accounts for more than 50% of the total radiation from the divertor. In PDD operation, produced by neutral gas injection, the particle flow to the target plate and the divertor temperature are significantly reduced. A father motivation was to study the CIV emission distribution in the lower, open divertor and the upper baffled divertor. Two Vacuum Ultra Violet Tangential viewing Television cameras (VUV TTV) were constructed and installed in the upper, baffled and the lower, open divertor. The images recorded by these cameras were then inverted to produce two-dimensional distributions of CIV in the poloidal plane. Results obtained in the project are summarized in this report

Effects of photoirradiation in UV and VUV regions during plasma exposure to polymers

International Nuclear Information System (INIS)

Cho, Ken; Setsuhara, Yuichi; Takenaka, Kosuke; Shiratani, Masaharu; Sekine, Makoto; Hori, Masaru

2011-01-01

Interactions between photons irradiated from Ar-O 2 mixture plasmas and polymer surfaces were investigated on the basis of depth analyses of chemical bonding states in the nano-surface layer of polyethylene terephthalate (PET) films via hard X-ray photoelectron spectroscopy (HXPES) and conventional X-ray photoelectron spectroscopy (XPS). The PET films were exposed to photons from the Ar-O 2 mixture plasmas by covering the PET samples with MgF 2 and quartz windows as optical filters for evaluation of photoirradiation effects in ultraviolet (UV) and vacuum ultraviolet (VUV) regions. The HXPES results indicated that the degradation of the chemical bonding states due to photoirradiation in regions was insignificant in deeper regions up to about 50 nm from the surface. Whereas, conventional XPS analysis showed that C-O bond, O=C-O bond and C=O bond increased after photoirradiation in UV and VUV regions. These results suggest that the increase in oxygen functionalities (C-O bond, O=C-O bond and C=O bond) may be attributed to chemical reactions and/or terminations of scissed bonds via photodecompositions of the polymer with oxygen and/or OH species (oxygen molecules and radicals during plasma exposure and/or oxygen molecules and moisture after taking the PET samples out of the plasma reactor to the ambient air) in the vicinity of the sample surface.

Weak carbonyl-methyl intermolecular interactions in acetone clusters explored by IR plus VUV spectroscopy

International Nuclear Information System (INIS)

Guan, Jiwen; Hu, Yongjun; Xie, Min; Bernstein, Elliot R.

2012-01-01

Highlights: ► The carbonyl overtone of acetone clusters is observed by IR-VUV spectroscopy. ► Acetone molecules in the dimer are stacked with an antiparallel way. ► The structure of the acetone trimer and the tetramer are the cyclic structures. ► The carbonyl groups would interact with the methyl groups in acetone clusters. ► These weak interactions are further confirmed by H/D substitution experiment. -- Abstract: Size-selected IR–VUV spectroscopy is employed to detect vibrational characteristics in the region 2850 ∼ 3550 cm −1 of neutral acetone and its clusters (CH 3 COCH 3 ) n (n = 1–4). Features around 3440 cm −1 in the spectra of acetone monomer and its clusters are assigned to the carbonyl stretch (CO) overtone. These features red-shift from 3455 to 3433 cm −1 as the size of the clusters increases from the monomer to the tetramer. Based on calculations, the experimental IR spectra in the C=O overtone region suggest that the dominant structures for the acetone trimer and tetramer should be cyclic in the supersonic expansion sample. This study also suggests that the carbonyl groups interact with the methyl groups in the acetone clusters. These weak interactions are further confirmed by the use of deuterium substitution.

Measurement quality assurance for radioassay laboratories

Energy Technology Data Exchange (ETDEWEB)

McCurdy, D.E. [Yankee Atomic Environmental Laboratory, Boston, MA (United States)

1993-12-31

Until recently, the quality of U.S. radioassay laboratory services has been evaluated by a limited number of governmental measurement assurance programs (MAPs). The major programs have been limited to the U.S. Department of Energy (DOE), the U.S. Environmental Protection Agency (EPA) and the U.S. Nuclear Regulatory Commission (NRC). In 1988, an industry MAP was established for the nuclear power utility industry through the U.S. Council for Energy Awareness/National Institute of Standards and Technology (USCEA/NIST). This program functions as both a MAP for utility laboratories and/or their commercial contractor laboratories, and as a traceability program for the U.S. radioactive source manufacturers and the utility laboratories. Each of these generic MAPs has been initiated and is maintained to serve the specific needs of the sponsoring agency or organization. As a result, there is diversification in their approach, scope, requirements, and degree of traceability to NIST. In 1987, a writing committee was formed under the American National Standards Institute (ANSI) N42.2 committee to develop a standard to serve as the basis document for the creation of a national measurement quality assurance (MQA) program for radioassay laboratories in the U.S. The standard is entitled, {open_quotes}Measurement Quality Assurance For Radioassay Laboratories.{open_quotes} The document was developed to serve as a guide for MQA programs maintained for the specialized sectors of the radioassay community, such as bioassay, routine environmental monitoring, environmental restoration and waste management, radiopharmaceuticals, and nuclear facilities. It was the intent of the writing committee to develop a guidance document that could be utilized to establish a laboratory`s specific data quality objectives (DQOs) that govern the operational requirements of the radioassay process, including mandated protocols and recommendations.

An inter-laboratory comparison of urinary 3-hydroxypropylmercapturic acid measurement demonstrates good reproducibility between laboratories

Directory of Open Access Journals (Sweden)

Bailey Brian

2011-10-01

Full Text Available Abstract Background Biomarkers have been used extensively in clinical studies to assess toxicant exposure in smokers and non-smokers and have recently been used in the evaluation of novel tobacco products. The urinary metabolite 3-HPMA, a metabolite of the major tobacco smoke toxicity contributor acrolein, is one example of a biomarker used to measure exposure to tobacco smoke. A number of laboratories have developed liquid chromatography with tandem mass spectrometry (LC-MS/MS based methods to measure urinary 3-HPMA; however, it is unclear to what extent the data obtained by these different laboratories are comparable. Findings This report describes an inter-laboratory comparison carried out to evaluate the comparability of 3-HPMA measurement between four laboratories. A common set of spiked and authentic smoker and non-smoker urine samples were used. Each laboratory used their in-house LC-MS/MS method and a common internal standard. A comparison of the repeatability ('r', reproducibility ('R', and coefficient of variation for 3-HPMA demonstrated that within-laboratory variation was consistently lower than between-laboratory variation. The average inter-laboratory coefficient of variation was 7% for fortified urine samples and 16.2% for authentic urine samples. Together, this represents an inter-laboratory variation of 12.2%. Conclusion The results from this first inter-laboratory comparison for the measurement of 3-HPMA in urine demonstrate a reasonably good consensus between laboratories. However, some consistent measurement biases were still observed between laboratories, suggesting that additional work may be required to further reduce the inter-laboratory coefficient of variation.

Magnet power supply control of the NSLS VUV and x-ray storage rings transfer lines

International Nuclear Information System (INIS)

Klein, J.D.; Ramamoorthy, S.; Singh, O.; Smith, J.D.

1985-01-01

The transfer lines for NSLS VUV and x-ray storage rings have been split. New power supplies have been incorporated with existing ones. The existing microprocessor system has been upgraded in order to control the additional functions. This system expands the input/output port of the microprocessor to an addressable serial/parallel link to each magnet power supply. The implementation of this system will be discussed

Comparison of different undulator schemes with superimposed alternating gradients for the VUV-FEL at the TESLA Test Facility

Energy Technology Data Exchange (ETDEWEB)

Pflueger, J.; Nikitina, Y.M. [DESY/HASYLAB, Hamburg (Germany)

1995-12-31

For the VUV-FEL at the TESLA Test Facility an undulator with a total length of 30 m is needed. In this study three different approaches to realize an undulator with a sinusoidal plus a superimposed quadrupolar field were studied with the 3D code MAFIA.

Determination of ionization energies of CnN (n=4-12): Vacuum-ultraviolet (VUV) photoionization experiments and theoretical calculations

International Nuclear Information System (INIS)

Kostko, Oleg; Zhou, Jia; Sun, Bian Jian; Lie, Jie Shiuan; Chang, Agnes H.H.; Kaiser, Ralf I.; Ahmed, Musahid

2010-01-01

Results from single photon vacuum ultraviolet photoionization of astrophysically relevant CnN clusters, n = 4 - 12, in the photon energy range of 8.0 eV to 12.8 eV are presented. The experimental photoionization efficiency curves, combined with electronic structure calculations, provide improved ionization energies of the CnN species. A search through numerous nitrogen-terminated CnN isomers for n=4-9 indicates that the linear isomer has the lowest energy, and therefore should be the most abundant isomer in the molecular beam. Comparison with calculated results also shed light on the energetics of the linear CnN clusters, particularly in the trends of the even-carbon and the odd-carbon series. These results can help guide the search of potential astronomical observations of these neutral molecules together with their cations in highly ionized regions or regions with a high UV/VUV photon flux (ranging from the visible to VUV with flux maxima in the Lyman-a region) in the interstellar medium.

Cryogenic readout for multiple VUV4 Multi-Pixel Photon Counters in liquid xenon

Science.gov (United States)

Di Giovanni, A.

2018-03-01

This work concerned the preliminary tests and characterization of a cryogenic preamplifier board for an array made of 16 S13370-3050CN (VUV4 family) Multi-Pixel Photon Counters manufactured by Hamamatsu and operated at liquid xenon temperature. The proposed prototype is based on the use of the Analog Devices AD8011 current feedback operational amplifier. The detector allows for single photon detection, making this device a promising choice for the future generation of neutrino and dark matter detectors based on liquid xenon targets.

Measurement quality assurance for radioassay laboratories

International Nuclear Information System (INIS)

McCurdy, D.E.

1993-01-01

Until recently, the quality of U.S. radioassay laboratory services has been evaluated by a limited number of governmental measurement assurance programs (MAPs). The major programs have been limited to the U.S. Department of Energy (DOE), the U.S. Environmental Protection Agency (EPA) and the U.S. Nuclear Regulatory Commission (NRC). In 1988, an industry MAP was established for the nuclear power utility industry through the U.S. Council for Energy Awareness/National Institute of Standards and Technology (USCEA/NIST). This program functions as both a MAP for utility laboratories and/or their commercial contractor laboratories, and as a traceability program for the U.S. radioactive source manufacturers and the utility laboratories. Each of these generic MAPs has been initiated and is maintained to serve the specific needs of the sponsoring agency or organization. As a result, there is diversification in their approach, scope, requirements, and degree of traceability to NIST. In 1987, a writing committee was formed under the American National Standards Institute (ANSI) N42.2 committee to develop a standard to serve as the basis document for the creation of a national measurement quality assurance (MQA) program for radioassay laboratories in the U.S. The standard is entitled, open-quotes Measurement Quality Assurance For Radioassay Laboratories.open-quotes The document was developed to serve as a guide for MQA programs maintained for the specialized sectors of the radioassay community, such as bioassay, routine environmental monitoring, environmental restoration and waste management, radiopharmaceuticals, and nuclear facilities. It was the intent of the writing committee to develop a guidance document that could be utilized to establish a laboratory's specific data quality objectives (DQOs) that govern the operational requirements of the radioassay process, including mandated protocols and recommendations

Imaging with Mass Spectrometry: A SIMS and VUV-Photoionization Study of Ion-Sputtered Atoms and Clusters from GaAs and Au

Energy Technology Data Exchange (ETDEWEB)

Takahashi, Lynelle; Zhou, Jia; Wilson, Kevin R.; Leone, Stephen R.; Ahmed, Musahid

2008-12-05

A new mass spectrometry surface imaging method is presented in which ion-sputtered neutrals are postionized by wavelength-tunable vacuum ultraviolet (VUV) light from a synchrotron source. Mass spectra and signal counts of the photoionized neutrals from GaAs (100) and Au are compared to those of the secondary ions. While clusters larger than dimers are more efficiently detected as secondary ions, certain species, such as As2, Au and Au2, are more efficiently detected through the neutral channel. Continuously tuning the photon wavelength allows photoionization efficiency (PIE) curves to be obtained for sputtered Asm (m=1,2) and Aun (n=1-4). From the observed ionization thresholds, sputtered neutral As and Au show no clear evidence of electronic excitation, while neutral clusters have photoionization onsets shifted to lower energies by ~;;0.3 eV. These shifts are attributed to unresolved vibrational and rotational excitations. High-spatial resolution chemical imaging with synchrotron VUV postionization is demonstrated at two different photon energies using a copper TEM grid embedded in indium. The resulting images are used to illustrate the use of tunable VUV light for verifying mass peak assignments by exploiting the unique wavelength-dependent PIE of each sputtered neutral species. This capability is valuable for identifying compounds when imaging chemically complex systems with mass spectrometry-based techniques.

Separation of VUV/UV photons and reactive particles in the effluent of a He/O{sub 2} atmospheric pressure plasma jet

Energy Technology Data Exchange (ETDEWEB)

Schneider, S; Benedikt, J [Coupled plasma-solid state systems, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, Universitaetsstr. 150, 44780 Bochum (Germany); Lackmann, J-W; Narberhaus, F; Bandow, J E [Mikrobiologie, Fakultaet fuer Biologie, Ruhr-Universitaet Bochum, Universitaetsstr. 150, 44780 Bochum (Germany); Denis, B [Institute for Electrical Engineering and Plasma Technology, Ruhr-Universitaet Bochum, Universitaetsstr. 150, 44780 Bochum (Germany)

2011-07-27

Cold atmospheric pressure plasmas can be used for treatment of living tissues or for inactivation of bacteria or biological macromolecules. The treatment is usually characterized by a combined effect of UV and VUV radiation, reactive species and ions. This combination is usually beneficial for the effectiveness of the treatment but it makes the study of fundamental interaction mechanisms very difficult. Here we report on an effective separation of VUV/UV photons and heavy reactive species in the effluent of a microscale atmospheric pressure plasma jet ({mu}-APPJ). The separation is realized by an additional flow of helium gas under well-defined flow conditions, which deflects heavy particles in the effluent without affecting the VUV and UV photons. Both components of the effluent, the photons and the reactive species, can be used separately or in combination for sample treatment. The results of treatment of a model plasma polymer film and vegetative Bacillus subtilis and Escherichia coli cells are shown and discussed. A simple model of the He gas flow and reaction kinetics of oxygen atoms in the gas phase and at the surface is used to provide a better understanding of the processes in the plasma effluent. The new jet modification, called X-Jet for its appearance, will simplify the investigation of interaction mechanisms of atmospheric pressure plasmas with biological samples.

Proton and electron impact on molecular and atomic oxygen: I. High resolution fluorescence spectra in the visible and VUV spectral range and emission cross-sections for dissociative ionisation and excitation of O2

International Nuclear Information System (INIS)

Wilhelmi, O.; Schartner, K.H.

2000-01-01

For pt.II see ibid., vol.11, p.45-58, 2000. Molecular oxygen O 2 was dissociated in collisions with protons and electrons in the intermediate velocity range (p + -energies: 17-800 keV, e - -energies: 0.2-2 keV). Fluorescence from excited atomic and singly ionised fragments and from singly ionised molecules was detected in the VUV and in the visible and near UV spectral range. Highly resolved spectra are presented for the VUV (46-131 nm) and the near UV/visible (340-605 nm) spectral range. Absolute emission cross-sections have been determined for dissociative ionisation and excitation leading to fluorescence in the VUV. Results are compared with published data. (orig.)

Rain Erosion/Measurement Impact Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The FARM Rain Erosion/Impact Measurement Lab develops solutions for deficiencies in the ability of materials, coatings and designs to withstand a severe operational...

Second Order Harmonics Suppression With Glass Filters for Synchrotron UV Radiation Calibration Measurement

CERN Document Server

Burattini, E; Gambicorti, L; Malvezzi, F; Marcelli, A; Monti, F; Pace, E

2005-01-01

This development is the latest result of the cooperation between the National Laboratories of Frascati and the Department of Astronomy and Space Science of the University of Florence to improve the capabilities of the existing DXR-2 beam line at the DAΦNE-LIGHT laboratories. This collaboration has assessed a new facility in order to characterize optics and sensors in a wide spectral range (ranging from VUV to IR). Previous measurements [1] have highlighted some limitations in the present setup, as higher signal levels due to the diffracted radiation of the grating in the second order have to be removed to allow an accurate detection. In this work a glass filter is used to remove such spurious signal present in the spectral region with λ > 360 nm. The characteristics of the filter and its application to the optical system used to measure the sensitivity of a diamond-based photoconductor have been discussed.

Purdue Rare Isotope Measurement Laboratory

Science.gov (United States)

Caffee, M.; Elmore, D.; Granger, D.; Muzikar, P.

2002-12-01

The Purdue Rare Isotope Measurement Laboratory (PRIME Lab) is a dedicated research and service facility for accelerator mass spectrometry. AMS is an ultra-sensitive analytical technique used to measure low levels of long-lived cosmic-ray-produced and anthropogenic radionuclides, and rare trace elements. We measure 10Be (T1/2 = 1.5 My), 26Al (.702 My), 36Cl (.301 My), and 129I (16 My), in geologic samples. Applications include dating the cosmic-ray-exposure time of rocks on Earth's surface, determining rock and sediment burial ages, measuring the erosion rates of rocks and soils, and tracing and dating ground water. We perform sample preparation and separation chemistries for these radio-nuclides for our internal research activities and for those external researchers not possessing this capability. Our chemical preparation laboratories also serve as training sites for members of the geoscience community developing these techniques at their institutions. Research at Purdue involves collaborators among members of the Purdue Departments of Physics, Earth and Atmospheric Sciences, Chemistry, Agronomy, and Anthropology. We also collaborate and serve numerous scientists from other institutions. We are currently in the process of modernizing the facility with the goals of higher precision for routinely measured radio-nuclides, increased sample throughput, and the development of new measurement capabilities for the geoscience community.

VUV spectroscopy of pure LiCaAlF6 crystals

International Nuclear Information System (INIS)

Kirm, M.; True, M.; Vielhauer, S.; Zimmerer, G.; Shiran, N.V.; Shpinkov, I.; Spassky, D.; Shimamura, K.; Ichinose, N.

2005-01-01

Reflection, excitation and luminescence spectra of as-grown and X-ray irradiated high-purity LiCaAlF 6 crystals were studied in the temperature range of 10-300 K using synchrotron radiation in VUV. The intrinsic luminescence of samples at 10 K consists of a non-elementary broad band with maximum at 4.4 eV under excitation at 11.45 eV. It is ascribed to the radiative decay of self-trapped excitons. The energy gap is estimated to be 12.65 eV in LiCaAlF 6 . Under interband excitation a red shift of luminescence was observed. The electron-hole recombination leads to the emission peaking at 3.7 eV. The excitation processes and origin of overlapping emissions of LiCaAlF 6 are discussed

Vacuum ultraviolet (VUV) absorption spectra of chromatin and its components

International Nuclear Information System (INIS)

Dodonova, N.Y.; Kiseleva, M.N.; Petrov, M.Y.; Tsyganenko, N.M.; Bubyakina, V.V.; Chikhirzhina, G.I.

1984-01-01

The electron absorption spectra of thin films of chromatin and chromatin components in the ultraviolet region (140-280 nm) were investigated. The absorption coefficients μ(lambda) of chromatin, nucleosomes with and without histone H1, total histones (TH), and DNA were compared. The spectra of nucleosomes differ from the sum-spectrum of DNA plus TH. The chromatin and nucleosome spectra are not similar in the spectral region of 190-160 nm. The lack of additivity of absorption coefficients at different wavelengths may be explained by different conformational changes of DNA, TH in nucleosomes and chromatin during the process of drying aqueous solutions for the preparation of thin films. The μ(lambda) values are useful for an estimate of the DNA and TH absorption in chromatin and nucleosomes in discussing UV and VUV irradiation damages. (Auth.)

VUV Optics Development for the Elettra Storage Ring FEL

CERN Document Server

Guenster, Stefan

2004-01-01

Vacuum ultraviolet optical components for the storage ring FEL at Elettra are under continuous development in the European research consortium EUFELE. Target of the project is the progress to shorter lasing wavelengths in the VUV spectral range. The current status allows lasing with oxide mirror systems down to 190 nm. The main obstacles for the development of optical coatings for shorter wavelengths is the high energetic background of the synchrotron radiation impinging onto the front mirror in the laser cavity. Investigations in single layer systems and multilayer stacks of oxide or fluoride materials demonstrate that fluoride mirrors reach highest reflectivity values down to 140 nm, and oxide coatings possess a satisfactory resistance against the high energetic background irradiation. However, pure oxide multilayer stacks exhibit significant absorption below 190 nm and pure fluoride stacks suffer from strong degradation effects under synchrotron radiation. A solution could be hybrid systems, combining fluo...

Progress on resonance ionization detection of combustion radicals

International Nuclear Information System (INIS)

Cool, T.A.

1994-01-01

Selective laser ionization techniques are used in our laboratory for the measurement of concentration profiles of radical intermediates in the combustion of chlorinated hydrocarbon flames. A new ultrasensitive detection technique, made possible with the advent of tunable VUV laser sources, enables the selective near-threshold photoionization of all radical intermediates in premixed hydrocarbon and chlorinated hydrocarbon flames. The progress made on the following three separate experiments during the past year is briefly described in this report. Flame Radical Concentration Measurements with VUV Spectroscopy; observation of hyperfine quantum beats in cyanogen; and the spectroscopy of the ClCO radical

Fire preparedness measures in buildings with hot laboratories

International Nuclear Information System (INIS)

Oberlaender, B.C.

2003-01-01

Important hot laboratory safety issues are the general design/construction of the building with respect to fire, fire prevention, fire protection, administrative controls, and risk assessment. Within the network of the European Working Group Hot Laboratories and Remote Handling items concerning 'fire preparedness measures in hot laboratories' were screened and studied. Two questionnaires were sent to European hot laboratories; the first in November 2002 on 'fire preparedness measures, fire detection and fire suppression/extinguishing in lead shielded cells, concrete shielded cells' and the second in June 2003 on 'Fire preparedness measures in buildings with hot laboratories'. The questionnaires were filled in by a total of ten hot laboratories in seven European countries. On request of participants the answers were evaluated and 'anonymised' for presentation and discussion at the plenary meeting. The answers showed that many European hot laboratories are implementing improvements to their fire protection programmes to comply with more stringent requirements of the national authorities. The recommendations ('International guidelines for the fire protection of Nuclear Power Plants') given by the insurance pools are followed up with national variations. An ISO standard (ISO 17873) is in progress giving criteria for the design and the operation of ventilation systems as well as fire hazard management in nuclear installations others than reactors

Spectral-kinetic characteristics of Pr3+ luminescence in LiLuF4 host upon excitation in the UV-VUV range

International Nuclear Information System (INIS)

Stryganyuk, G.; Zimmerer, G.; Shiran, N.; Voronova, V.; Nesterkina, V.; Gektin, A.; Shimamura, K.; Villora, E.; Jing, F.; Shalapska, T.; Voloshinovskii, A.

2008-01-01

Spectral-kinetic study of Pr 3+ luminescence has been performed for LiLuF 4 :Pr(0.1 mol%) single crystal upon the excitation within 5-12 eV range at T=8 K. The fine-structure of Pr 3+ 4f 2 →4f 5d excitation spectra is shown for LiLuF 4 :Pr(0.1 mol%) to be affected by the efficient absorption transitions of Pr 3+ ions into 4f 5d involving 4f 1 core in the ground state. Favourable conditions have been revealed in LiLuF 4 :Pr(0.1 mol%) for the transformation of UV-VUV excitation quanta into the visible range. Lightly doped LiLuF 4 :Pr crystals are considered as the promising luminescent materials possessing the efficient Pr 3+3 P 0 visible emission upon UV-VUV excitation. The mechanism of energy transfer between Lu 3+ host ion and Pr 3+ impurity is discussed

Photoionization Efficiencies of Five Polycyclic Aromatic Hydrocarbons.

Science.gov (United States)

Johansson, K Olof; Campbell, Matthew F; Elvati, Paolo; Schrader, Paul E; Zádor, Judit; Richards-Henderson, Nicole K; Wilson, Kevin R; Violi, Angela; Michelsen, Hope A

2017-06-15

We have measured photoionization-efficiency curves for pyrene, fluoranthene, chrysene, perylene, and coronene in the photon energy range of 7.5-10.2 eV and derived their photoionization cross-section curves in this energy range. All measurements were performed using tunable vacuum ultraviolet (VUV) radiation generated at the Advanced Light Source synchrotron at Lawrence Berkeley National Laboratory. The VUV radiation was used for photoionization, and detection was performed using a time-of-flight mass spectrometer. We measured the photoionization efficiency of 2,5-dimethylfuran simultaneously with those of pyrene, fluoranthene, chrysene, perylene, and coronene to obtain references of the photon flux during each measurement from the known photoionization cross-section curve of 2,5-dimethylfuran.

8-channel, FPGA based, DSP integrated cavity simulator and controller for VUV-FEL. SIMCON 3.0 Ver. 3.0. rev. 1, 06.2005 - Hardware manual

International Nuclear Information System (INIS)

Pozniak, K.T.; Czarski, T.; Koprek, W.; Giergusiewicz, W.; Romaniuk, R.S.

2005-01-01

The note describes integrated, eight channel system of hardware controller and simulator of the resonant superconducting, narrowband niobium cavity, originally considered for the TTF and TESLA in DESY, Hamburg (now tested for the VUV FEL and developed for X-Ray FEL). The controller bases on a programmable circuit Xilinx VirtexII V4000. The solution uses DSP EMBEDDED BOARD module positioned on a Modular LLRF Control Platform. The algorithm and FPGA circuit configuration was done in the VHDL language. The internal hardware multiplication components, present in Virtex II chips, were used, to improve the floating point calculation efficiency. The implementation was achieved of a device working in the real time, according to the demands of the LLRF control system for the TESLA Test Facility (now associated with the VUV FEL machine). The device under consideration will be referred to as superconducting cavity (SCCav) SIMCON throughout this work. The manual describes hardware features of SIMCON, ver. 3.0 in modular solution. The following components are described here in detail: functional layer, parameter programming, foundations of control of particular blocks and monitoring of the real time processes. This note is accompanied by the one describing the multichannel DOOCS interface for the described hardware system. The interface was prepared in DOOCS for Solaris and in Windows. The hardware and software of 8-channel SIMCON was tested in CHECIA and ACC1 module of VUV FEL linac. The measurements results are presented. While giving all necessary technical details required to understand the work of the integrated hardware controller and simulator and to enable its practical copying, this document is a unity with other TESLA technical notes published by the same team on the subject. Thus, some modeling and other subjects were omitted, as they were addressed in detail in the quoted references. Keywords: Super conducting cavity, cavity simulator, CAVITIES CONTROLLER, SIMCON

Accreditation - Its relevance for laboratories measuring radionuclides

Energy Technology Data Exchange (ETDEWEB)

Palsson, S E [Icelandic Radiation Protection Inst. (Iceland)

2001-11-01

Accreditation is an internationally recognised way for laboratories to demonstrate their competence. Obtaining and maintaining accreditation is, however, a costly and time-consuming procedure. The benefits of accreditation also depend on the role of the laboratory. Accreditation may be of limited relevance for a research laboratory, but essential for a laboratory associated with a national authority and e.g. issuing certificates. This report describes work done within the NKSBOK-1.1 sub-project on introducing accreditation to Nordic laboratories measuring radionuclides. Initially the focus was on the new standard ISO/IEC 17025, which was just in a draft form at the time, but which provides now a new framework for accreditation of laboratories. Later the focus was widened to include a general introduction to accreditation and providing through seminars a forum for exchanging views on the experience laboratories have had in this field. Copies of overheads from the last such seminar are included in the appendix to this report. (au)

The linear lattice design of an advanced VUV/SXR photon source for Daresbury

International Nuclear Information System (INIS)

Clarke, J.A.; Corlett, J.N.; Poole, M.W.; Smith, S.L.; Suller, V.P.; Welbourne, L.A.

1992-01-01

The linear lattice design of an advanced synchrotron radiation source in the VUV/SXR region, optimised to produce undulator radiation with high brilliance over the range 5-1000 eV, is discussed. The photon source is based on a 10 cell double bend achromat which will operate over the range 0.5-1.2 GeV. The linear lattice properties over the total available working region are presented for this structure. It is demonstrated that the circular lattice can be extended to a racetrack configuration by the inclusion of two long matched straights with free lengths of over 15 m each. (author) 8 refs.; 5 figs.; 1 tab

Photochemical defluorination of aqueous perfluorooctanoic acid (PFOA) by Fe(0)/GAC micro-electrolysis and VUV-Fenton photolysis.

Science.gov (United States)

Zhang, Li-Hong; Cheng, Jian-Hua; You, Xia; Liang, Xiao-Yan; Hu, Yong-You

2016-07-01

Perfluorooctanoic acid (PFOA) is extremely persistent and bioaccumulative in the environment; thus, it is very urgent to investigate an effective and moderate technology to treat the pollution of PFOA. In this study, a process combined iron and granular activated carbon (Fe(0)/GAC) micro-electrolysis with VUV-Fenton system is employed for the remediation of PFOA. Approximately 50 % PFOA (10 mg L(-1)) could be efficiently defluorinated under the following conditions: pH 3.0, dosage of Fe 7.5 g L(-1), dosage of GAC 12.5 g L(-1), and concentration of H2O2 22.8 mmol L(-1). Meanwhile, during the process, evident defluorination was observed and the concentration of fluoride ion was eventually 3.23 mg L(-1). The intermediates including five shorter-chain perfluorinated carboxylic acids (PFCAs), i.e., C7, C6, C5, C4, and C3, were also analyzed by high-performance liquid chromatography tandem mass spectrometry (HPLC/MS/MS) and defluorination mechanisms of PFOA was proposed, which involved photochemical of OH·, direct photolysis (185-nm VUV), and photocatalytic degradation of PFOA in the presence of Fe(3+) (254-nm UV).

Optical transmittance investigation of 1-keV ion-irradiated sapphire crystals as potential VUV to NIR window materials of fusion reactors

Directory of Open Access Journals (Sweden)

Keisuke Iwano

2016-10-01

Full Text Available We investigate the optical transmittances of ion-irradiated sapphire crystals as potential vacuum ultraviolet (VUV to near-infrared (NIR window materials of fusion reactors. Under potential conditions in fusion reactors, sapphire crystals are irradiated with hydrogen (H, deuterium (D, and helium (He ions with 1-keV energy and ∼ 1020-m-2 s-1 flux. Ion irradiation decreases the transmittances from 140 to 260 nm but hardly affects the transmittances from 300 to 1500 nm. H-ion and D-ion irradiation causes optical absorptions near 210 and 260 nm associated with an F-center and an F+-center, respectively. These F-type centers are classified as Schottky defects that can be removed through annealing above 1000 K. In contrast, He-ion irradiation does not cause optical absorptions above 200 nm because He-ions cannot be incorporated in the crystal lattice due to the large ionic radius of He-ions. Moreover, the significant decrease in transmittance of the ion-irradiated sapphire crystals from 140 to 180 nm is related to the light scattering on the crystal surface. Similar to diamond polishing, ion irradiation modifies the crystal surface thereby affecting the optical properties especially at shorter wavelengths. Although the transmittances in the VUV wavelengths decrease after ion irradiation, the transmittances can be improved through annealing above 1000 K. With an optical transmittance in the VUV region that can recover through simple annealing and with a high transparency from the ultraviolet (UV to the NIR region, sapphire crystals can therefore be used as good optical windows inside modern fusion power reactors in terms of light particle loadings of hydrogen isotopes and helium.

Availability of urinary albumin measurement in Southern Brazilian laboratories

Directory of Open Access Journals (Sweden)

Ariana Aguiar Soares

2015-03-01

Full Text Available Introduction: Diabetic kidney disease (DKD is the leading worldwide cause of end-stage renal disease. The current recommendation is to screen for DKD by evaluating estimated glomerular filtration rate (eGFR and measuring urinary albumin (UA levels in a spot sample. The aim of this study was to evaluate the availability of UA measurement in Southern Brazilian laboratories.   Methods: A cross-sectional study was conducted to assess the routine use of UA in all laboratories registered in the State Pharmacy Council ofRio Grande do Sul, the southernmost state ofBrazil. Data was collected by mail, e-mail, telephone, or personal interview. A sample size of at least 384 laboratories was necessary to achieve 5% precision at a 95% confidence level based on a fixed proportion of 0.5.   Results: Eight hundred and eighty laboratories currently registered in the state were invited to participate in the study; 548 (62% answered the technical specification questionnaire. Only 306 (55% of the 548 surveyed laboratories performed UA measurements. The laboratories were also required to provide the number of UA measurements performed per day, which ranged from less than one per week to 65 per day.  Conclusion: The availability of UA measurements is undesirably low inSouthern Brazil. This demonstrates the urgent need to increase the availability of this important test. It also reveals the gap between the current guidelines and the awareness about them among health care professionals.

Performance of a novel VUV bending magnet beamline

CERN Document Server

Song, Y F; Hsieh, T F; Huang, L R; Chung, S C; Cheng, N F; Hsiung, G Y; Wang, D J; Chen, C T; Tsang, K L

2001-01-01

A novel high resolution, high flux bending magnet beamline with an energy range from 5 to 40 eV has been constructed at SRRC. This Dragon-like beamline, which horizontally collects 50 mrad of synchrotron radiation from a bending magnet source, uses four cylindrical gratings with an included angle of 140 deg. and a movable curved exit slit. The average photon flux with an energy resolving power of 1000 is about 2x10 sup 1 sup 2 photons/s, which is among the highest of all existing VUV bending magnet beamlines. An energy resolving power of 24,000 at 6.8 eV has been obtained from the Schumann-Runge bands (B sup 3 limit construction operator in a limit construction/sum L: summation operator operator End lower limit of a limit construction u lower limit End limit End sup - /leftarrow/gets A: =leftward arrow X sup 3 limit construction operator in a limit construction/sum L: summation operator operator End lower limit of a limit construction g lower limit End limit End sup -) absorption spectra of O sub 2 gas. A pho...

Environmental Measurements Laboratory (EML) procedures manual

International Nuclear Information System (INIS)

Chieco, N.A.; Bogen, D.C.; Knutson, E.O.

1990-11-01

Volume 1 of this manual documents the procedures and existing technology that are currently used by the Environmental Measurements Laboratory. A section devoted to quality assurance has been included. These procedures have been updated and revised and new procedures have been added. They include: sampling; radiation measurements; analytical chemistry; radionuclide data; special facilities; and specifications. 228 refs., 62 figs., 37 tabs. (FL)

Intensity calibrations of the broadband VUV impurity survey spectrometer - KT2

International Nuclear Information System (INIS)

Hawkes, N.; Peacock, N.; Lawson, K.

1991-08-01

Since first becoming operational in 1984 the survey spectrometer, KT2, has undergone slight modifications on the Joint European Torus Joint Undertaking (JET), and following a failure at one point the original spectrometer-'A', was exchanged for an almost identical instrument-'B'. Periodically, calibrations have been performed on the diagnostic using the diverse techniques of charge exchange branching ratios, deuterium lamp transfer irradiance standard, branching ratios from visible transitions, VUV transfer radiance standard and model calculations of line intensities in low Z ions from JET. Comparisons have been made with the theoretical instrument performance and with the prototype instruments of similar construction. This report summarises these various calibrations, carried out by the Culham Task Agreement team, until the end of 1990 when the responsability for the operation of the diagnostic was handed over to JET staff. (author)

VUV treatment combined with mechanical strain of stretchable polymer foils resulting in cell alignment

Energy Technology Data Exchange (ETDEWEB)

Barb, R.-A. [Institute of Applied Physics, Johannes Kepler University Linz (Austria); Magnus, B. [Innovacell Biotechnologie AG, Innsbruck (Austria); Innerbichler, S. [Innerbichler GmbH, Breitenbach am Inn (Austria); Greunz, T. [CDL-MS-MACH, Johannes Kepler University Linz (Austria); Wiesbauer, M. [Institute of Applied Physics, Johannes Kepler University Linz (Austria); Marksteiner, R. [Innovacell Biotechnologie AG, Innsbruck (Austria); Stifter, D. [CDL-MS-MACH, Johannes Kepler University Linz (Austria); Heitz, J., E-mail: johannes.heitz@jku.at [Institute of Applied Physics, Johannes Kepler University Linz (Austria)

2015-01-15

Highlights: • Elastic polyurethane (PU) foils were exposed to the vacuum-UV in reactive atmosphere. • The photomodification resulted in improved cytocompatibilty. • Parallel microgrooves formed on the irradiated PU surfaces after strong elongation. • Cells seeded onto microgrooves aligned their shapes in the direction of the grooves. • Elongation occurred also for cells on PU subjected to cyclic mechanical stretching. - Abstract: Cell-alignment along a defined direction can have a direct effect on the cell functionality and differentiation. Oriented micro- or nanotopographic structures on cell culture substrates can induce cell-alignment. Surface chemistry, wettability, and stiffness of the substrate are also important material features as they strongly influence the cell–substrate interactions. For improved bio-compatibility, highly elastic polyurethane (PU) foils were exposed to the vacuum-UV (VUV) light of a Xe{sub 2}{sup *} excimer lamp at 172 nm in a nitrogen containing atmosphere (N{sub 2} or NH{sub 3}). The irradiation resulted in a change in the chemical surface composition. Additionally, the formation of regular parallel microgrooves was observed on the irradiated surfaces after strong uni-axial deformation (i.e., more than about 50% strain) of the photo-modified PU foils. Cell seeding experiments demonstrated that the VUV modified polymer foils strongly enhance cell adhesion and proliferation. Cells seeded onto microgrooves aligned their shapes and elongated in the direction of the grooves. A similar effect was observed for cells seeded on photo-modified PU foils subjected to cyclic mechanical stretching at lower strain levels (i.e., typically 10% strain) without groove-formation. The cells had also here an elongated shape, however they not always align in a defined direction relative to the stretching.

Two-color photoionization and photoelectron studies by combining infrared and vacuum ultraviolet

International Nuclear Information System (INIS)

Ng, C.Y.

2005-01-01

Recent developments of two-color infrared (IR)-vacuum ultraviolet (VUV) and VUV-IR photoionization and photoelectron detection schemes for spectroscopic studies are described. By preparing molecules in selected rovibrational states by IR excitation prior to VUV-photoionization, state-selected and state-to-state photoionization cross sections can be obtained by IR-VUV-photoionization efficiency (IR-VUV-PIE) and IR-VUV-pulsed field ionization-photoelectron (IR-VUV-PFI-PE) measurements, respectively. Rotationally resolved autoionizing Rydberg states converging to excited ionic states, which cannot be observed by single-photon VUV-PIE measurements, can be examined by the IR-VUV-PIE scheme. By monitoring the photoion and the PFI-PE intensities at a fixed VUV energy as a function of IR frequency, the respective IR photoion and IR absorption spectra of the corresponding neutral molecule can be measured. Two-color VUV-IR photo-induced Rydberg ionization (PIRI) experiment, in which high-n Rydberg states are prepared by VUV-photoexcitation followed by IR-induced autoionization, has also been demonstrated. Since the IR-VUV-PIE, IR-VUV-PFI-PE, and VUV-IR-PIRI methods do not require the existence of a bound intermediate electronic state in the UV and are generally applicable to all molecules, the development of these two-color photoionization and photoelectron schemes is expected to significantly enhance the scope of VUV spectroscopy and chemistry

PTB’s radiometric scales for UV and VUV source calibration based on synchrotron radiation

Science.gov (United States)

Klein, Roman; Kroth, Simone; Paustian, Wolfgang; Richter, Mathias; Thornagel, Reiner

2018-06-01

The radiant intensity of synchrotron radiation can be accurately calculated with classical electrodynamics. This primary realization of the spectral radiant intensity has been used by PTB at several electron storage rings which have been optimized to be operated as primary source standards for the calibration of transfer sources in the spectral range of UV and VUV for almost 30 years. The transfer sources are compared to the primary source standard by means of suitable wavelength-dispersive transfer stations. The spectral range covered by deuterium lamps, which represent transfer sources that are easy to handle, is of particular relevance in practice. Here, we report on developments in the realization and preservation of the radiometric scales for spectral radiant intensity and spectral radiance in the wavelength region from 116 nm to 400 nm, based on a set of deuterium reference lamps, over the last few decades. An inside view and recommendations on the operation of the D2 lamps used for the realization of the radiometric scale are presented. The data has been recently compiled to illustrate the chronological behaviour at various wavelengths. Moreover, an overview of the internal and external validation measurements and intercomparisons is given.

Methyl Radicals in Oxidative Coupling of Methane Directly Confirmed by Synchrotron VUV Photoionization Mass Spectroscopy

Science.gov (United States)

Luo, Liangfeng; Tang, Xiaofeng; Wang, Wendong; Wang, Yu; Sun, Shaobo; Qi, Fei; Huang, Weixin

2013-01-01

Gas-phase methyl radicals have been long proposed as the key intermediate in catalytic oxidative coupling of methane, but the direct experimental evidence still lacks. Here, employing synchrotron VUV photoionization mass spectroscopy, we have directly observed the formation of gas-phase methyl radicals during oxidative coupling of methane catalyzed by Li/MgO catalysts. The concentration of gas-phase methyl radicals correlates well with the yield of ethylene and ethane products. These results lead to an enhanced fundamental understanding of oxidative coupling of methane that will facilitate the exploration of new catalysts with improved performance. PMID:23567985

Modeling of synchrotron-based laboratory simulations of Titan's ionospheric photochemistry

Science.gov (United States)

Carrasco, Nathalie; Peng, Zhe; Pernot, Pascal

2014-11-01

The APSIS reactor has been designed to simulate in the laboratory with a VUV synchrotron irradiation the photochemistry occurring in planetary upper atmospheres. A N2-CH4 Titan-like gas mixture has been studied, whose photochemistry in Titan's ionospheric irradiation conditions leads to a coupled chemical network involving both radicals and ions. In the present work, an ion-neutral coupled model is developed to interpret the experimental data, taking into account the uncertainties on the kinetic parameters by Monte Carlo sampling. The model predicts species concentrations in agreement with mass spectrometry measurements of the methane consumption and product blocks intensities. Ion chemistry and in particular dissociative recombination are found to be very important through sensitivity analysis. The model is also applied to complementary environmental conditions, corresponding to Titan's ionospheric average conditions and to another existing synchrotron setup. An innovative study of the correlations between species concentrations identifies two main competitive families, leading respectively to saturated and unsaturated species. We find that the unsaturated growth family, driven by C2H2 , is dominant in Titan's upper atmosphere, as observed by the Cassini INMS. But the saturated species are substantially more intense in the measurements of the two synchrotron experimental setups, and likely originate from catalysis by metallic walls of the reactors.

Measuring meaningful learning in the undergraduate chemistry laboratory

Science.gov (United States)

Galloway, Kelli R.

The undergraduate chemistry laboratory has been an essential component in chemistry education for over a century. The literature includes reports on investigations of singular aspects laboratory learning and attempts to measure the efficacy of reformed laboratory curriculum as well as faculty goals for laboratory learning which found common goals among instructors for students to learn laboratory skills, techniques, experimental design, and to develop critical thinking skills. These findings are important for improving teaching and learning in the undergraduate chemistry laboratory, but research is needed to connect the faculty goals to student perceptions. This study was designed to explore students' ideas about learning in the undergraduate chemistry laboratory. Novak's Theory of Meaningful Learning was used as a guide for the data collection and analysis choices for this research. Novak's theory states that in order for meaningful learning to occur the cognitive, affective, and psychomotor domains must be integrated. The psychomotor domain is inherent in the chemistry laboratory, but the extent to which the cognitive and affective domains are integrated is unknown. For meaningful learning to occur in the laboratory, students must actively integrate both the cognitive domain and the affective domains into the "doing" of their laboratory work. The Meaningful Learning in the Laboratory Instrument (MLLI) was designed to measure students' cognitive and affective expectations and experiences within the context of conducting experiments in the undergraduate chemistry laboratory. Evidence for the validity and reliability of the data generated by the MLLI were collected from multiple quantitative studies: a one semester study at one university, a one semester study at 15 colleges and universities across the United States, and a longitudinal study where the MLLI was administered 6 times during two years of general and organic chemistry laboratory courses. Results from

Mobile Radiological Laboratories Intercomparison Measurements - Chernobyl

International Nuclear Information System (INIS)

Martincic, R.; Glavic-Cindro, D.; Korun, M.; Pucelj, B.; Vodenik, B.

2001-01-01

Full text: In last decade different institutions in European countries have organised periodic intercomparison exercises of mobile radiological laboratories to improve the preparedness of emergency monitoring teams. The 12th Regular Workshop on Mobile Radiological Laboratories was held in Exclusion Zone of the Chernobyl NPP, Ukraine from September 13 to September 18, 1999 under the acronym MORAL-12. The European Centre of Technological Safety (TESEC), Kiev, Ukraine and J. Stefan Institute, Ljubljana, Slovenia organised Intercomparison Measurements 99 jointly under the auspices of the International Atomic Energy Agency (IAEA). Nineteen teams from 9 countries and IAEA participated in the Workshop. Six field and personal and equipment contamination control exercises were prepared and conducted at two measuring sites with very different ambient dose rate levels. The Workshop pointed out that such exercises are very valuable for rapid, efficient and harmonised emergency response in case of nuclear or radiological emergency. The teams had an opportunity to test their ability to perform field measurements in the contaminated environment, and to report results on the spot, as well as to test their emergency preparedness and persistence. They gained new experiences for fieldwork under stress conditions. An overview and results of these intercomparison measurements are presented and lessons learned are discussed. (author)

VUV photoionization of acetamide studied by electron/ion coincidence spectroscopy in the 8-24 eV photon energy range

KAUST Repository

Schwell, Martin; Bé nilan, Yves; Fray, Nicolas; Gazeau, Marie Claire; Es-sebbar, Et-touhami; Garcí a, Gustavo A.; Nahon, Laurent; Champion, Norbert; Leach, Sydney Sydney

2012-01-01

A VUV photoionization study of acetamide was carried out over the 8-24 eV photon energy range using synchrotron radiation and photoelectron/photoion coincidence (PEPICO) spectroscopy. Threshold photoelectron photoion coincidence (TPEPICO) measurements were also made. Photoion yield curves and branching ratios were measured for the parent ion and six fragment ions. The adiabatic ionization energy of acetamide was determined as I.E. (1 2A′) = (9.71 ± 0.02) eV, in agreement with an earlier reported photoionization mass spectrometry (PIMS) value. The adiabatic energy of the first excited state of the ion, 1 2A″, was determined to be ≈10.1 eV. Assignments of the fragment ions and the pathways of their formation by dissociative photoionization were made. The neutral species lost in the principal dissociative photoionization processes are CH 3, NH 2, NH 3, CO, HCCO and NH 2CO. Heats of formation are derived for all ions detected and are compared with literature values. Some astrophysical implications of these results are discussed. © 2011 Elsevier B.V. All rights reserved.

Future prospect of the research study using intense and bright synchrotron radiation in VUV and soft x-ray region

International Nuclear Information System (INIS)

Tanaka, Kenichiro; Miyahara, Tsuneaki

1987-02-01

This report is the summary of the contents of the study meeting 'Future prospect of the research study using intense and bright synchrotron radiation in VUV and soft x-ray region' sponsored by PF, held on October 20 and 21, 1986. This study meeting was held by inviting those who are particularly interested in the basic field among the users of VUV and soft x-ray region, and the research on the application field was excluded. The objective of the discussion of this study meeting was to talk about the dream that if a high luminance light source which is 100 - 1000 times more intense in terms of luminous flux intensity is completed, what can we do with it. Three sessions on the themes 'How the existing research fields will develop', 'What the possible new research fields are' and 'Comment from the technical aspect' were held. More than seven years elapsed since the beginning of construction of the Photon Factory. Many excellent results have been obtained. As of October, 1986, the beam lines available for experiment are 11, the themes of common utilization experiment in progress are 300, and the number of registered researchers exceeded 1000. The development of a new light emission source is to be undertaken. (Kako, I.)

Measurement Instruments and Software Used in Biotribology Research Laboratory

Directory of Open Access Journals (Sweden)

Tyurin Andrei

2015-07-01

Full Text Available Precision measurements of friction processes have a key role in a variety of industrial processes. The emergence of fine electronic circuit techniques greatly expands capabilities of control. There are some difficulties for their full implementation today, especially when it regards the accuracy and frequency of measurements. The motion-measuring method in real-time system is considered in this article, paying special attention to increased accuracy. This method is based on rapid analog digital converter (ADC, transmission program and digital signal processor (DSP algorithms. Description of laboratory devices is included: Tribal-T and universal friction machine (MTU-01 designed for “Pin on disc” tests. Great emphasis is placed on the usability of accelerometers. The present study examined the collected data via laboratory system for data acquisition and control, and processing it in the laboratory of Biotribology. Laboratory supervisory control and data acquisition (SCADA algorithms is described below. Task of regulation is not considered. This paper describes only methods of automatic control theory to analyze the frictional quality.

Measuring preschool learning engagement in the laboratory.

Science.gov (United States)

Halliday, Simone E; Calkins, Susan D; Leerkes, Esther M

2018-03-01

Learning engagement is a critical factor for academic achievement and successful school transitioning. However, current methods of assessing learning engagement in young children are limited to teacher report or classroom observation, which may limit the types of research questions one could assess about this construct. The current study investigated the validity of a novel assessment designed to measure behavioral learning engagement among young children in a standardized laboratory setting and examined how learning engagement in the laboratory relates to future classroom adjustment. Preschool-aged children (N = 278) participated in a learning-based Tangrams task and Story sequencing task and were observed based on seven behavioral indicators of engagement. Confirmatory factor analysis supported the construct validity for a behavioral engagement factor composed of six of the original behavioral indicators: attention to instructions, on-task behavior, enthusiasm/energy, persistence, monitoring progress/strategy use, and negative affect. Concurrent validity for this behavioral engagement factor was established through its associations with parent-reported mastery motivation and pre-academic skills in math and literacy measured in the laboratory, and predictive validity was demonstrated through its associations with teacher-reported classroom learning behaviors and performance in math and reading in kindergarten. These associations were found when behavioral engagement was observed during both the nonverbal task and the verbal story sequencing tasks and persisted even after controlling for child minority status, gender, and maternal education. Learning engagement in preschool appears to be successfully measurable in a laboratory setting. This finding has implications for future research on the mechanisms that support successful academic development. Copyright © 2017 Elsevier Inc. All rights reserved.

Interaction ligand – proteine : la sensation d’astringence sous les rayons VUV de DESIRS

OpenAIRE

Canon, Francis

2013-01-01

L’astringence est la sensation d’assèchement et de rugosité à l’intérieur de la bouche qui accompagne la consommation de produits d’origine végétale, tels que le vin ou le thé, ou certains fruits peu mûrs. Les tanins, métabolites secondaires des végétaux, sont à l’origine de cette sensation, qui reste encore mal caractérisée. Une nouvelle approche utilisant la spectrométrie de masse couplée au rayonnement VUV, développée sur les lignes DESIRS et DISCO, a permis de mieux comprendre les mécanis...

Radon measurements during the building of a low-level laboratory

CERN Document Server

Antanasijevic, R; Bikit, I; Banjanac, R; Dragic, A; Joksimovic, D; Krmpotic, D; Udovicic, V; Vukovic, J

1999-01-01

Radon measurements were provided during the different stages of building of a low-level laboratory in Belgrade. The depth of the laboratory is 12 m, equivalent to 30 m of water with an area of 45 m sup 2. The whole of the laboratory is hermetically lined with 1 mm A1 foil and is ventilated with filtered air. Radon concentrations were measured with the CR-39 detector as well as via the gamma-ray spectroscopic measurements. The radon concentrations in the air were achieved to 20 Bqm sup - sup 3 and reduction of secondary and tertiary cosmic-ray fluxes is five times when ventilation, filtering and sealing was applied.

Radon measurements during the building of a low-level laboratory

Energy Technology Data Exchange (ETDEWEB)

Antanasijevic, R.; Anicin, I.; Bikit, I.; Banjanac, R.; Dragic, A.; Joksimovic, D.; Krmpotic, D.; Udovicic, V.; Vukovic, J

1999-06-01

Radon measurements were provided during the different stages of building of a low-level laboratory in Belgrade. The depth of the laboratory is 12 m, equivalent to 30 m of water with an area of 45 m{sup 2}. The whole of the laboratory is hermetically lined with 1 mm A1 foil and is ventilated with filtered air. Radon concentrations were measured with the CR-39 detector as well as via the gamma-ray spectroscopic measurements. The radon concentrations in the air were achieved to 20 Bqm{sup -3} and reduction of secondary and tertiary cosmic-ray fluxes is five times when ventilation, filtering and sealing was applied.

Radon measurements during the building of a low-level laboratory

International Nuclear Information System (INIS)

Antanasijevic, R.; Anicin, I.; Bikit, I.; Banjanac, R.; Dragic, A.; Joksimovic, D.; Krmpotic, D.; Udovicic, V.; Vukovic, J.

1999-01-01

Radon measurements were provided during the different stages of building of a low-level laboratory in Belgrade. The depth of the laboratory is 12 m, equivalent to 30 m of water with an area of 45 m 2 . The whole of the laboratory is hermetically lined with 1 mm A1 foil and is ventilated with filtered air. Radon concentrations were measured with the CR-39 detector as well as via the gamma-ray spectroscopic measurements. The radon concentrations in the air were achieved to 20 Bqm -3 and reduction of secondary and tertiary cosmic-ray fluxes is five times when ventilation, filtering and sealing was applied

A HIGH REPETITION RATE VUV-SOFT X-RAY FEL CONCEPT

International Nuclear Information System (INIS)

Corlett, J.; Byrd, J.; Fawley, W.M.; Gullans, M.; Li, D.; Lidia, S.M.; Padmore, H.; Penn, G.; Pogorelov, I.; Qiang, J.; Robin, D.; Sannibale, F.; Staples, J.W.; Steier, C.; Venturini, M.; Virostek, S.; Wan, W.; Wells, R.; Wilcox, R.; Wurtele, J.; Zholents, A.

2007-01-01

We report on design studies for a seeded FEL light source that is responsive to the scientific needs of the future. The FEL process increases radiation flux by several orders of magnitude above existing incoherent sources, and offers the additional enhancements attainable by optical manipulations of the electron beam: control of the temporal duration and bandwidth of the coherent output, reduced gain length in the FEL, utilization of harmonics to attain shorter wavelengths, and precise synchronization of the x-ray pulse with seed laser systems. We describe an FEL facility concept based on a high repetition rate RF photocathode gun, that would allow simultaneous operation of multiple independent FEL's, each producing high average brightness, tunable over the VUV-soft x-ray range, and each with individual performance characteristics determined by the configuration of the FEL. SASE, enhanced-SASE (ESASE), seeded, harmonic generation, and other configurations making use of optical manipulations of the electron beam may be employed, providing a wide range of photon beam properties to meet varied user demands

Gain length dependence on phase shake in the VUV-FEL at the TESLA Test Facility

Energy Technology Data Exchange (ETDEWEB)

Pflueger, J. [DESY/HASYLAB, Hamburg (Germany); Schneidmiller, E.A. [Automatic Systems Corporation, Samara (Russian Federation); Pierini, P. [INFN, Milano (Italy)

1995-12-31

The TTF VUV FEL, which is in its design stage at DESY, consists of a 30 m long SASE FEL which will radiate around 6 nm, driven by a superconducting linac with final energy of 1 GeV. One of the important issues in its design is the undulator performance, which is studied in this paper. The present setup, including FODO lattice, is discussed in this paper. Results of simulations, including the realistic wiggler field errors and beam stearing, are presented. Dependence of the performance, in particular the gain and saturation length as well as the saturation peak power, on the wiggler field errors is discussed.

A measurement evaluation program to support nuclear material control and accountability measurements in Brazilian laboratories

International Nuclear Information System (INIS)

Dias, Fabio C.; Mason, Peter

2013-01-01

A measurement evaluation program (MEP) is one of a number of valuable tools that analytical chemists can use to ensure that the data produced in the laboratory are fit for their intended purpose and consistent with expected performance values at a given time. As such, participation in a MEP is an important indicator of the quality of analytical data, and is recognized as such by independent regulatory and/or accreditation bodies. With the intent to implement such a program in Brazil, in November 2012 the Nuclear Energy Commission of Brazil (CNEN), with support from the Department of Energy of the United States' (US-DOE International Safeguards and Engagement Program), decided to initiate a technical cooperation project aiming at organizing a Safeguards Measurement Evaluation Program (SMEP) for Brazilian facilities. The project, entitled Action Sheet 23, was formalized under the terms of the Agreement between the US-DOE and the CNEN concerning research and development in nuclear material control, accountancy, verification, physical protection, and advanced containment and surveillance technologies for International Safeguards Applications. The work, jointly performed by the CNEN's Safeguards Laboratory (LASAL) and the New Brunswick Laboratory (NBL), has the objective to strengthen the traceability of accountability measurements and ensure adequate quality of safeguards measurements for facilities within Brazil, utilizing test samples characterized and provided by NBL. Recommendations to participants included measurement frequency, number of results per sample and format for reporting results using ISO methods for calculating and expressing measurement uncertainties. In this paper, we discuss the main steps taken by CNEN and NBL aiming at implementing such a program and the expected results, in particular the impact of uncertainty estimation on the evaluation of performance of each participant laboratory. The program is considered by Brazilian safeguards authorities

A measurement evaluation program to support nuclear material control and accountability measurements in Brazilian laboratories

Energy Technology Data Exchange (ETDEWEB)

Dias, Fabio C., E-mail: fabio@ird.gov.br [Comissao Nacional de Energia Nuclear (CNEN-RJ), Rio de Janeiro, RJ (Brazil); Mason, Peter, E-mail: peter.mason@ch.doe.gov [New Brunswick Laboratory (DOE/NBL), Argonne, IL (United States)

2013-07-01

A measurement evaluation program (MEP) is one of a number of valuable tools that analytical chemists can use to ensure that the data produced in the laboratory are fit for their intended purpose and consistent with expected performance values at a given time. As such, participation in a MEP is an important indicator of the quality of analytical data, and is recognized as such by independent regulatory and/or accreditation bodies. With the intent to implement such a program in Brazil, in November 2012 the Nuclear Energy Commission of Brazil (CNEN), with support from the Department of Energy of the United States' (US-DOE International Safeguards and Engagement Program), decided to initiate a technical cooperation project aiming at organizing a Safeguards Measurement Evaluation Program (SMEP) for Brazilian facilities. The project, entitled Action Sheet 23, was formalized under the terms of the Agreement between the US-DOE and the CNEN concerning research and development in nuclear material control, accountancy, verification, physical protection, and advanced containment and surveillance technologies for International Safeguards Applications. The work, jointly performed by the CNEN's Safeguards Laboratory (LASAL) and the New Brunswick Laboratory (NBL), has the objective to strengthen the traceability of accountability measurements and ensure adequate quality of safeguards measurements for facilities within Brazil, utilizing test samples characterized and provided by NBL. Recommendations to participants included measurement frequency, number of results per sample and format for reporting results using ISO methods for calculating and expressing measurement uncertainties. In this paper, we discuss the main steps taken by CNEN and NBL aiming at implementing such a program and the expected results, in particular the impact of uncertainty estimation on the evaluation of performance of each participant laboratory. The program is considered by Brazilian safeguards

Intercomparison Measurements Exercises of Mobile Radiological Laboratories (invited paper)

International Nuclear Information System (INIS)

Martincic, R.

2000-01-01

After the reactor accident in Chernobyl, the importance of mobile radiological laboratories became evident and in situ gamma spectrometry became a common method for the rapid detection of gamma emitters in the environment. Since then different institutions in European countries have organised periodic intercomparison exercises of mobile radiological laboratories to improve the measurement methods and the preparedness of emergency monitoring teams. The general objectives of these workshops are to promote the knowledge and to exchange the experiences of emergency monitoring teams that use mobile radiological laboratories, as well as to foster the international harmonisation of emergency monitoring procedures and cooperation among teams. Finally, the results of intercomparison measurements have shown that such exercises are mandatory for rapid, efficient and correct environmental monitoring in nuclear or radiological emergencies. An overview of these intercomparison measurements is given, results from the 1999 intercomparison workshop are presented and lessons learned are discussed. (author)

Interstellar PAH in the Laboratory and in Space. What have we Learned from the New Generation of Laboratory and Observational Studies?

Science.gov (United States)

Salama, Farid

2005-01-01

Polycyclic Aromatic Hydrocarbons (PAHs) are an important and ubiquitous component of carbon-bearing materials in space. PAHs are the best-known candidates to account for the IR emission bands (UIR bands) and PAH spectral features are now being used as new probes of the ISM. PAHs are also thought to be among the carriers of the diffuse interstellar absorption bands (DIBs). In the model dealing with the interstellar spectral features, PAHs are present as a mixture of radicals, ions and neutral species. PAH ionization states reflect the ionization balance of the medium while PAH size, composition, and structure reflect the energetic and chemical history of the medium. A major challenge for laboratory astrophysics is to reproduce (in a realistic way) the physical conditions that exist in the emission and/or absorption interstellar zones. An extensive laboratory program has been developed at NASA Ames to assess the physical and chemical properties of PAHs in such environments and to describe how they influence the radiation and energy balance in space and the interstellar chemistry. In particular, laboratory experiments provide measurements of the spectral characteristics of interstellar PAH analogs from the ultraviolet and visible range to the infrared range for comparison with astronomical data. This paper will focus on the recent progress made in the laboratory to measure the direct absorption spectra of neutral and ionized PAHs in the gas phase in the near-UV and visible range in astrophysically relevant environments. These measurements provide data on PAHs and nanometer-sized particles that can now be directly compared to astronomical observations. The harsh physical conditions of the IS medium - characterized by a low temperature, an absence of collisions and strong VUV radiation fields - are simulated in the laboratory by associating a molecular beam with an ionizing discharge to generate a cold plasma expansion. PAH ions are formed from the neutral precursors in

Measurement uncertainty. A practical guide for Secondary Standards Dosimetry Laboratories

International Nuclear Information System (INIS)

2008-05-01

The need for international traceability for radiation dose measurements has been understood since the early nineteen-sixties. The benefits of high dosimetric accuracy were recognized, particularly in radiotherapy, where the outcome of treatments is dependent on the radiation dose delivered to patients. When considering radiation protection dosimetry, the uncertainty may be greater than for therapy, but proper traceability of the measurements is no less important. To ensure harmonization and consistency in radiation measurements, the International Atomic Energy Agency (IAEA) and the World Health Organization (WHO) created a Network of Secondary Standards Dosimetry Laboratories (SSDLs) in 1976. An SSDL is a laboratory that has been designated by the competent national authorities to undertake the duty of providing the necessary link in the traceability chain of radiation dosimetry to the international measurement system (SI, for Systeme International) for radiation metrology users. The role of the SSDLs is crucial in providing traceable calibrations; they disseminate calibrations at specific radiation qualities appropriate for the use of radiation measuring instruments. Historically, although the first SSDLs were established mainly to provide radiotherapy level calibrations, the scope of their work has expanded over the years. Today, many SSDLs provide traceability for radiation protection measurements and diagnostic radiology in addition to radiotherapy. Some SSDLs, with the appropriate facilities and expertise, also conduct quality audits of the clinical use of the calibrated dosimeters - for example, by providing postal dosimeters for dose comparisons for medical institutions or on-site dosimetry audits with an ion chamber and other appropriate equipment. The requirements for traceable and reliable calibrations are becoming more important. For example, for international trade where radiation products are manufactured within strict quality control systems, it is

Automation of measurements in the dclf laboratory of the CSIR NML

CSIR Research Space (South Africa)

Marais, EL

2006-01-01

Full Text Available At the end of 2005 it was decided that a number of measurements performed in the dc Low Frequency (dclf) Laboratory of the CSIR National Metrology Laboratory (CSIR NML) could benefit from automation. The measurements identified were typically highly...

Laboratory measurements of rock thermal properties

DEFF Research Database (Denmark)

Bording, Thue Sylvester; Balling, N.; Nielsen, S.B.

The thermal properties of rocks are key elements in understanding and modelling the temperature field of the subsurface. Thermal conductivity and thermal diffusivity can be measured in the laboratory if rock samples can be provided. We have introduced improvements to the divided bar and needle...... probe methods to be able to measure both thermal conductivity and thermal diffusivity. The improvements we implement include, for both methods, a combination of fast numerical finite element forward modelling and a Markov Chain Monte Carlo inversion scheme for estimating rock thermal parameters...

VUV/UV light inducing accelerated phenol degradation with a low electric input† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c6ra26043h Click here for additional data file.

Science.gov (United States)

Li, Mengkai; Wen, Dong

2017-01-01

This study presents the first evidence for the accelerated degradation of phenol by Fenton's reagent in a mini-fluidic VUV/UV photoreaction system (MVPS). A low-pressure mercury lamp used in the MVPS led to a complete degradation of phenol within 4–6 min. The HO˙ and HO2˙ originating from both Fenton's reagent and VUV photolysis of water were identified with suitable radical scavengers. The effects of initial concentrations of phenol, H2O2 and Fe3+ as well as solution pH on phenol degradation kinetics were examined. Increasing the initial phenol concentration slowed down the phenol degradation, whereas increasing the initial H2O2 or Fe3+ concentration accelerated the phenol degradation. The optimal solution pH was 3.7. At both 254 and 185 nm, increasing phenol concentration enhanced its absorption for the incident photons. The reaction mechanism for the degradation of phenol was suggested consistent with the results obtained. This study indicates that the VUV/UV photo-Fenton process has potential applications in the treatment of industrial wastewater containing phenol and related aromatic pollutants. PMID:28496972

Laboratory setup for temperature and humidity measurements

CERN Document Server

Eimre, Kristjan

2015-01-01

In active particle detectors, the temperature and humidity conditions must be under constant monitoring and control, as even small deviations from the norm cause changes to detector characteristics and result in a loss of precision. To monitor the temperature and humidity, different kinds of sensors are used, which must be calibrated beforehand to ensure their accuracy. To calibrate the large number of sensors that are needed for the particle detectors and other laboratory work, a calibration system is needed. The purpose of the current work was to develop a laboratory setup for temperature and humidity sensor measurements and calibration.

Electrical measurements in the laboratory practice

CERN Document Server

Bartiromo, Rosario

2016-01-01

This book covers the basic theory of electrical circuits, describes analog and digital instrumentation, and applies modern methods to evaluate uncertainties in electrical measurements. It is comprehensive in scope and is designed specifically to meet the needs of students in physics and electrical engineering who are attending laboratory classes in electrical measurements. The topics addressed in individual chapters include the analysis of continuous current circuits; sources of measurement uncertainty and their combined effect; direct current measurements; analysis of alternating current circuits; special circuits including resonant circuits, frequency filters and impedance matching networks; alternating current measurements; analog and digital oscilloscopes; non-sinusoidal waveforms and circuit excitation by pulses; distributed parameter components and transmission lines. Each chapter is equipped with a number of problems. A special appendix describes a series of nine experiments, in each case providing a p...

Cryogenic readout for multiple VUV4 Multi-Pixel Photon Counters in liquid xenon

Science.gov (United States)

Arneodo, F.; Benabderrahmane, M. L.; Bruno, G.; Conicella, V.; Di Giovanni, A.; Fawwaz, O.; Messina, M.; Candela, A.; Franchi, G.

2018-06-01

We present the performances and characterization of an array made of S13370-3050CN (VUV4 generation) Multi-Pixel Photon Counters manufactured by Hamamatsu and equipped with a low power consumption preamplifier operating at liquid xenon temperature (∼ 175 K). The electronics is designed for the readout of a matrix of maximum dimension of 8 × 8 individual photosensors and it is based on a single operational amplifier. The detector prototype presented in this paper utilizes the Analog Devices AD8011 current feedback operational amplifier, but other models can be used depending on the application. A biasing correction circuit has been implemented for the gain equalization of photosensors operating at different voltages. The results show single photon detection capability making this device a promising choice for future generation of large scale dark matter detectors based on liquid xenon, such as DARWIN.

Comparative study of bedside and laboratory measurements of hemoglobin.

Science.gov (United States)

Krenzischek, D A; Tanseco, F V

1996-11-01

The purpose of this study was to examine the effects of variations in technique on measurements of hemoglobin level done at the bedside and to compare these results with laboratory measurements of hemoglobin. In accordance with hospital policy, procedure, and protocol, various techniques were used to obtain samples of capillary and venous blood and of blood from arterial and central venous catheters. Levels of hemoglobin were measured at the bedside and in the laboratory, and the results were compared. The Johns Hopkins Hospital adult postanesthesia care unit. A total of 187 blood samples were obtained from 62 adults who had undergone general surgery. Group I comprised 20 subjects with capillary and venous blood samples. Group II comprised 21 subjects with arterial blood samples. Group III comprised 21 subjects with central venous blood samples. The results showed that the amount of blood to be discarded before obtaining samples of arterial and central venous blood need not be any larger than double the dead space of the catheter, and that shaking the blood sample for 10 seconds was sufficient to mix the sample before measurement of hemoglobin levels. Results of bedside and laboratory measurements of hemoglobin level were comparable. Bedside measurement of hemoglobin increases efficiency in patient care, decreases risk of blood-transmitted infection for staff, and decreases cost to the patient. However, the persons who perform the assay must be responsible in adhering to the standard of practice to minimize errors in the measurements.

Relaxation and excitation electronic processes in dielectrics irradiated by ultrafast IR and VUV pulses; Processus electroniques d'excitation et de relaxation dans les solides dielectriques excites par des impulsions IR et XUV ultracourtes

Energy Technology Data Exchange (ETDEWEB)

Gaudin, J

2005-11-15

We studied excitation and relaxation of electrons involved during interaction of visible and VUV femtosecond pulses with dielectrics. The generated population of hot electrons, having energy of few eV to few tens of eV above the bottom of the conduction band, is responsible of phenomena ranging to defect creation to optical breakdown. Owing to two techniques: photoemission and transient photoconductivity we improve the understanding of the The first photoemission experiments deal with dielectrics irradiated by 30 fs IR pulses. The photoemission spectra measured show a large population of electrons which energy rise up to 40 eV. We interpret this result in terms of a new absorption process: direct multi-photons inter-branch transitions. The 2. type of photoemission experiments are time resolved 'pump/probe' investigation. We study the relaxation of electrons excited by a VUV pulses. We used the high order harmonics (HOH) as light sources. We found surprisingly long decay time in the range of ps timescale. Last type of experiments is photoconductivity studies of diamond samples. Using HOH as light source we measure the displacement current induced by excited electrons in the conduction band. Those electrons relax mainly by impact ionisation creating secondary electrons. Hence by probing the number of electrons we were able to measure the efficiency of these relaxation processes. We observe a diminution of this efficiency when the energy of exciting photons is above 20 eV. Owing to Monte-Carlo simulation we interpret this result in terms of band structure effect. (author)

Portable laboratories for radioactivity measurements

International Nuclear Information System (INIS)

Damljanovic, D.; Smelcerovic, M.; Koturovic, A.; Drndarevic, V.; Sobajic, M.

1989-01-01

The portable radiometric laboratories LARA-10, LARA-GS, LARA-86 and ALARA-10 designed, developed and produced at the Boris Kidric Institute are described. Earlier models (LARA-1, LARA-1D, LARA-2 and LARA-5) are presented in brief. The basic characteristics of the devices and methods of measurements are given. All the instruments are battery operated and almost all can also use 220V/50Hz supply. They are a very suitable facility for radiological monitoring of soil, water, food, clothes etc., when working in field conditions (author)

Measurements of SIMCON 3.1 LLRF control signal processing quality for VUV free-electron laser FLASH

Science.gov (United States)

Pietrasik, Rafal; Giergusiewicz, Wojciech; Jalmuzna, Wojciech; Pozniak, Krzysztof T.; Romaniuk, Ryszard S.; Simrock, Stefan

2006-10-01

The paper describes development of a new version of photonic and electronic control and measurement system for FLASH Laser under development in DESY Hamburg accelerator laboratory. The system is called SIMCON 3.1. and is a developmental continuation of previous systems SIMCON 1.0, SIMCON 2.1 and SIMCON 3.0. It differs from the previous systems by considerably bigger resources: 10 fast analog input channels, bigger FPGA chip with two power PC - CPU units, two multi-gigabit optical links, GbE interface, booting possibility from flash memory card. The PCB is done in VME mechanical and electrical standard. It is designed for usage in tests for FLASH Laser development.

Latest developments at the ALBA magnetic measurements laboratory

Science.gov (United States)

Marcos, J.; Massana, V.; García, L.; Campmany, J.

2018-02-01

ALBA is a third-generation synchrotron light source that has been in operation since 2012 near Barcelona. A magnetic measurements laboratory has been associated with the facility since its very early stages and has been active for the last 20 years. In the first part of this work, the different instruments available at the laboratory are described, and a brief overview of the measurement campaigns carried out during its 20 years of history is presented. In the second part, a more detailed description of the approach to Hall probe measurements adopted at ALBA is offered, with an explanation of the methods and ancillary equipment that have been developed along the years in order to improve the accuracy of the system. In the third part, a new concept of Hall probe bench devoted to the measurement of closed structures is presented. The in-house design and building of a prototype for such a bench is described, together with its mechanical and magnetic characterization. As a conclusion, the first results obtained with this bench are discussed.

Study of the absorption and energy transfer processes in inorganic luminescent materials in the UV and VUV region; Etude des processus d`absorption et de transfert d`energie au sein de materiaux inorganiques luminescents dans le domaine UV et VUV

Energy Technology Data Exchange (ETDEWEB)

Mayolet, A

1995-11-29

In order to find a green emitting phosphor showing high quantum efficiency and a short decay time which can be used in the color Plasma Display Panels developed by Thomson-TTE-TIV company, a VUV spectrophotometer built at IPN Orsay, using the synchrotron radiation from the SUPER-ACO storage ring as an excitation source, allow us the simultaneous recording of the luminescence excitation and diffuse reflectivity spectra of the inorganic compounds in the UV-VUV range. In addition, this experimental set-up enable us to determine the luminescence quantum efficiency of phosphors in the whole energy range of investigation. The chemical synthesis of rare-earth ortho-- and metaborate and rare-earth ortho- and metaphosphate doped with trivalent lanthanide ions cerium, praseodymium, europium and terbium have been made. The energy variation of the thresholds of the luminescence excitation mechanisms in function of the nature and the structure of the host matrix is discussed. We have determined the influence of the nephelauxetic effect and the crystal field intensity on the energy of the f-d inter-configuration transitions. The variation of the luminescence quantum efficiency of the dopant ion is interpreted through the `impurity bound exciton` model. The systematic comparison of the cerium and terbium trivalent ions spectroscopic properties in the Y(AG)G host lattice series stands to reason that the self-ionized state of the luminescent center plays an important role in the rate of the non radiative relaxation. It is the redox power of the host matrix which imposes to the luminescent center, the energy of this state. (author) 134 refs.

VUV photoemission studies of candidate Large Hadron Collider vacuum chamber materials

Directory of Open Access Journals (Sweden)

R. Cimino

1999-06-01

Full Text Available In the context of future accelerators and, in particular, the beam vacuum of the Large Hadron Collider (LHC, a 27 km circumference proton collider to be built at CERN, VUV synchrotron radiation (SR has been used to study both qualitatively and quantitatively candidate vacuum chamber materials. Emphasis is given to show that angle and energy resolved photoemission is an extremely powerful tool to address important issues relevant to the LHC, such as the emission of electrons that contributes to the creation of an electron cloud which may cause serious beam instabilities and unmanageable heat loads on the cryogenic system. Here we present not only the measured photoelectron yields from the proposed materials, prepared on an industrial scale, but also the energy and in some cases the angular dependence of the emitted electrons when excited with either a white light (WL spectrum, simulating that in the arcs of the LHC, or monochromatic light in the photon energy range of interest. The effects on the materials examined of WL irradiation and /or ion sputtering, simulating the SR and ion bombardment expected in the LHC, were investigated. The studied samples exhibited significant modifications, in terms of electron emission, when exposed to the WL spectrum from the BESSY Toroidal Grating Monochromator beam line. Moreover, annealing and ion bombardment also induce substantial changes to the surface thereby indicating that such surfaces would not have a constant electron emission during machine operation. Such characteristics may be an important issue to define the surface properties of the LHC vacuum chamber material and are presented in detail for the various samples analyzed. It should be noted that all the measurements presented here were recorded at room temperature, whereas the majority of the LHC vacuum system will be maintained at temperatures below 20 K. The results cannot therefore be directly applied to these sections of the machine until

Study of the absorption and energy transfer processes in inorganic luminescent materials in the UV and VUV region

International Nuclear Information System (INIS)

Mayolet, A.

1995-01-01

In order to find a green emitting phosphor showing high quantum efficiency and a short decay time which can be used in the color Plasma Display Panels developed by Thomson-TTE-TIV company, a VUV spectrophotometer built at IPN Orsay, using the synchrotron radiation from the SUPER-ACO storage ring as an excitation source, allow us the simultaneous recording of the luminescence excitation and diffuse reflectivity spectra of the inorganic compounds in the UV-VUV range. In addition, this experimental set-up enable us to determine the luminescence quantum efficiency of phosphors in the whole energy range of investigation. The chemical synthesis of rare-earth ortho-- and metaborate and rare-earth ortho- and metaphosphate doped with trivalent lanthanide ions cerium, praseodymium, europium and terbium have been made. The energy variation of the thresholds of the luminescence excitation mechanisms in function of the nature and the structure of the host matrix is discussed. We have determined the influence of the nephelauxetic effect and the crystal field intensity on the energy of the f-d inter-configuration transitions. The variation of the luminescence quantum efficiency of the dopant ion is interpreted through the 'impurity bound exciton' model. The systematic comparison of the cerium and terbium trivalent ions spectroscopic properties in the Y(AG)G host lattice series stands to reason that the self-ionized state of the luminescent center plays an important role in the rate of the non radiative relaxation. It is the redox power of the host matrix which imposes to the luminescent center, the energy of this state. (author)

Magnetic measurements at Lawrence Berkeley Laboratory

International Nuclear Information System (INIS)

Green, M.I.; Barale, P.; Callapp, L.; Case-Fortier, M.; Lerner, D.; Nelson, D.; Schermer, R.; Skipper, G.; Van Dyke, D.; Cork, C.

1992-01-01

Recent magnetic measurement activities at LBL have been concentrated in two separate areas, electro-magnets and permanent magnets for the Advanced Light Source (ALS), and superconducting magnets for the Superconducting Super Collider Laboratory (SSCL). In this paper a survey of the many different measurement systems is presented. These include: AC magnetic measurements of an ALS booster dipole engineering model magnet, dipole moment measurements of permanent magnet blocks for ALS wigglers and undulators, permeability measurements of samples destined for wiggler and undulator poles, harmonic error analysis of SSC one meter model dipoles and quadrupoles and five meter long SSC prototype quadrupoles, harmonic error analysis of ALS dipoles, quadrupoles, and sextupoles, precision Hall probe mapping of ALS design of the ALS insertion device magnetic mapping system. The authors also describe a new UNIX based data acquisition system that is being developed for the SSC. Probes used for magnetic measurements include Helmholtz coils, integral coils, point coils, and bucking harmonic analysis coils, several different types of Hall probes, and nuclear magnetic resonance magnetometers

Environmental Measurements Laboratory fiscal year 1998: Accomplishments and technical activities

Energy Technology Data Exchange (ETDEWEB)

Erickson, M.D.

1999-01-01

The Environmental Measurements Laboratory (EML) is government-owned, government-operated, and programmatically under the DOE Office of Environmental Management. The Laboratory is administered by the Chicago Operations Office. EML provides program management, technical assistance and data quality assurance for measurements of radiation and radioactivity relating to environmental restoration, global nuclear nonproliferation, and other priority issues for the Department of Energy, as well as for other government, national, and international organizations. This report presents the technical activities and accomplishments of EML for Fiscal Year 1998.

Comparison of field-measured radon diffusion coefficients with laboratory-measured coefficients

International Nuclear Information System (INIS)

Lepel, E.A.; Silker, W.B.; Thomas, V.W.; Kalkwarf, D.R.

1983-04-01

Experiments were conducted to compare radon diffusion coefficients determined for 0.1-m depths of soils by a steady-state method in the laboratory and diffusion coefficients evaluated from radon fluxes through several-fold greater depths of the same soils covering uranium-mill tailings. The coefficients referred to diffusion in the total pore volume of the soils and are equivalent to values for the quantity, D/P, in the Generic Environmental Impact Statement on Uranium Milling prepared by the US Nuclear Regulatory Commission. Two soils were tested: a well-graded sand and an inorganic clay of low plasticity. For the flux evaluations, radon was collected by adsorption on charcoal following passive diffusion from the soil surface and also from air recirculating through an aluminum tent over the soil surface. An analysis of variance in the flux evaluations showed no significant difference between these two collection methods. Radon diffusion coefficients evaluated from field data were statistically indistinguishable, at the 95% confidence level, from those measured in the laboratory; however, the low precision of the field data prevented a sensitive validation of the laboratory measurements. From the field data, the coefficients were calculated to be 0.03 +- 0.03 cm 2 /s for the sand cover and 0.0036 +- 0.0004 cm 2 /s for the clay cover. The low precision in the coefficients evaluated from field data was attributed to high variation in radon flux with time and surface location at the field site

VUV and UV–vis optical study on KGd2F7 luminescent host doped with terbium and co-doped with europium

International Nuclear Information System (INIS)

Lisiecki, Radosław

2013-01-01

The KGd 2 F 7 :Tb and KGd 2 F 7 :Tb,Eu samples were obtained using a solid state reaction. Excitation spectra and emission spectra are reported and analyzed within the VUV–UV–vis spectral range. The intense green luminescence is observed in the KGd 2 F 7 :Tb while the combined emission of terbium and europium in the KGd 2 F 7 :Tb,Eu covers substantially the region of white light. The materials under study can be effectively excited making use of intense f–d transitions of Tb 3+ in the VUV–UV region. Experimental lifetimes of luminescent levels have been measured and discussed. It was found that the considerable energy transfer from Tb 3+ to Eu 3+ occurs. -- Highlights: • The prospective green and white emitting phosphors. • The effective VUV and UV–vis excitation process. • The considerable energy transfer among optically active ions. • The influence of (Tb, Eu) co-doping on relaxation dynamic of excited states

Measurements and modeling of total solar irradiance in X-class solar flares

International Nuclear Information System (INIS)

Moore, Christopher Samuel; Chamberlin, Phillip Clyde; Hock, Rachel

2014-01-01

The Total Irradiance Monitor (TIM) from NASA's SOlar Radiation and Climate Experiment can detect changes in the total solar irradiance (TSI) to a precision of 2 ppm, allowing observations of variations due to the largest X-class solar flares for the first time. Presented here is a robust algorithm for determining the radiative output in the TIM TSI measurements, in both the impulsive and gradual phases, for the four solar flares presented in Woods et al., as well as an additional flare measured on 2006 December 6. The radiative outputs for both phases of these five flares are then compared to the vacuum ultraviolet (VUV) irradiance output from the Flare Irradiance Spectral Model (FISM) in order to derive an empirical relationship between the FISM VUV model and the TIM TSI data output to estimate the TSI radiative output for eight other X-class flares. This model provides the basis for the bolometric energy estimates for the solar flares analyzed in the Emslie et al. study.

Evaluation of 1024 channel VUV-photo-diodes for soft x-ray diagnostic applications

International Nuclear Information System (INIS)

Molvik, A.W.

1997-01-01

We tested the operation of 1024 channel diode arrays (Model AXUV-1024, from IRD, Inc.) in subdued room light to establish that they worked and to determine the direction and speed of the scan of the 1024 channels. Further tests were performed in vacuum in the HAP, High-Average-Power Facility. There we found that the bare or glass covered diodes detected primarily visible light as expected, but diodes filtered by aluminized parylene, produced a signal consistent with soft x-rays. It is probable that the spectral response and sensitivity, as discussed below, reproduce that previously demonstrated by 1 to 16 channel VUV-photodiodes; however, significantly more effort would be required to establish that experimentally. These detectors appear to be worth further evaluation where 25 w spatial resolution bolometers or spectrograph detectors of known sensitivity are required, and single-shot or 0.02-0.2s time response is adequate. (Presumably, faster readout would be available with custom drive circuitry.)

Modernization of laboratories of test of electric measurer

International Nuclear Information System (INIS)

Cuervo, Luis Felipe

1999-01-01

The paper presents to the companies that possess test laboratories and calibration of electric measurer, an economic alternative for their modernization, using the repontentiation like an economic solution that it liberates resources to be used in other areas that they want it

Measurement of cosmic ray flux in the China Jinping underground laboratory

International Nuclear Information System (INIS)

Wu Yucheng; Hao Xiqing; Yue Qian

2013-01-01

The China JinPing underground Laboratory (CJPL) is the deepest underground laboratory running in the world at present. In such a deep underground laboratory, the cosmic ray flux is a very important and necessary parameter for rare-event experiments. A plastic scintillator telescope system has been set up to measure the cosmic ray flux. The performance of the telescope system has been studied using the cosmic rays on the ground laboratory near the CJPL. Based on the underground experimental data taken from November 2010 to December 2011 in the CJPL, which has an effective live time of 171 days, the cosmic ray muon flux in the CJPL is measured to be (2.0±0.4)×10 -10 /(cm 2 ·s). The ultra-low cosmic ray background guarantees an ideal environment for dark matter experiments at the CJPL. (authors)

Matrix diffusion studies by electrical conductivity methods. Comparison between laboratory and in-situ measurements

International Nuclear Information System (INIS)

Ohlsson, Y.; Neretnieks, I.

1998-01-01

Traditional laboratory diffusion experiments in rock material are time consuming, and quite small samples are generally used. Electrical conductivity measurements, on the other hand, provide a fast means for examining transport properties in rock and allow measurements on larger samples as well. Laboratory measurements using electrical conductivity give results that compare well to those from traditional diffusion experiments. The measurement of the electrical resistivity in the rock surrounding a borehole is a standard method for the detection of water conducting fractures. If these data could be correlated to matrix diffusion properties, in-situ diffusion data from large areas could be obtained. This would be valuable because it would make it possible to obtain data very early in future investigations of potentially suitable sites for a repository. This study compares laboratory electrical conductivity measurements with in-situ resistivity measurements from a borehole at Aespoe. The laboratory samples consist mainly of Aespoe diorite and fine-grained granite and the rock surrounding the borehole of Aespoe diorite, Smaaland granite and fine-grained granite. The comparison shows good agreement between laboratory measurements and in-situ data

Demonstration of two-electron (shake-up) photoionization and population inversions in the visible and VUV

International Nuclear Information System (INIS)

Silfvast, W.T.; Wood, O.R. II; Al-Salameh, D.Y.

1986-01-01

The two-electron (shake-up) photoionization process has been shown to be an effective mechanism for producing large population inversions in He/sup +/ with gain at 164 nm and in Ar/sup +/ with gain at 428 and 477 nm and for observing the first autoionizing states in Cd/sup +/. Such a mechanism was recently proposed as an excitation mechanism for a VUV laser in lithium. In each species the rapid excitation and detection using broadband emission from a 30-mJ 100-ps duration laser-produced plasma and a detection system with subnanosecond time resolution were essential in observing these effects. In He, gains of up to 0.8 cm/sup -1/ for durations of 2-4 ns at 164.0 nm on the He-like (n = 3-2) transition in He/sup +/ were measured by comparing the plasma emission from a well-defined volume with and without the presence of a mirror of known reflectivity. The n = 3 upper laser level is pumped not only directly via two-electron photoionization from the neutral ground state but also indirectly (in times of the order of 1-2 ns) via electron collisions from photoionization-pumped higher-lying levels. The decay rate of the photoionization-pumped radiation-trapped lower laser level is increased by a unique process involving absorption of radiation via photoionization of ground state neutral helium atoms

BaY2F8 single crystals doped with rare-earth ions as promising up-conversion media for UV and VUV lasers

International Nuclear Information System (INIS)

Pushkar', A A; Uvarova, T V; Molchanov, V N

2008-01-01

BaY 2 F 8 crystals are studied as promising active media for UV and VUV lasers. The up-conversion pumping of rare-earth activators is proposed to solve problems related to the solarisation of the medium and the selection of pump sources. The technology of growing oriented BaY 2 F 8 single crystals is developed and the influence of the crystal orientation on the growth rate and quality of single crystals is determined. (active media)

Trends in instrumentation for environmental radiation measurements at Los Alamos Scientific Laboratory

International Nuclear Information System (INIS)

Hiebert, R.D.; Wolf, M.A.

1980-01-01

Recent instruments developed to fulfill radiation monitoring needs at Los Alamos Scientific Laboratory are described. Laboratory instruments that measure tritium gas effluents alone, or in the presence of activated air from D-T fusion reactors are discussed. Fully portable systems for gamma, x-ray, and alpha analyses in the field are described. Also included are descriptions of survey instruments that measure low levels of transuranic contaminants and that measure pulsed-neutron dose rates

Performance audits and laboratory comparisons for SCOS97-NARSTO measurements of speciated volatile organic compounds

Science.gov (United States)

Fujita, Eric M.; Harshfield, Gregory; Sheetz, Laurence

Performance audits and laboratory comparisons were conducted as part of the quality assurance program for the 1997 Southern California Ozone Study (SCOS97-NARSTO) to document potential measurement biases among laboratories measuring speciated nonmethane hydrocarbons (NMHC), carbonyl compounds, halogenated compounds, and biogenic hydrocarbons. The results show that measurements of volatile organic compounds (VOC) made during SCOS97-NARSTO are generally consistent with specified data quality objectives. The hydrocarbon comparison involved nine laboratories and consisted of two sets of collocated ambient samples. The coefficients of variation among laboratories for the sum of the 55 PAM target compounds and total NMHC ranged from ±5 to 15 percent for ambient samples from Los Angeles and Azusa. Abundant hydrocarbons are consistently identified by all laboratories, but discrepancies occur for olefins greater than C 4 and for hydrocarbons greater than C 8. Laboratory comparisons for halogenated compounds and biogenic hydrocarbons consisted of both concurrent ambient sampling by different laboratories and round-robin analysis of ambient samples. The coefficients of variation among participating laboratories were about 10-20 percent. Performance audits were conducted for measurement of carbonyl compounds involving sampling from a standard mixture of carbonyl compounds. The values reported by most of the laboratories were within 10-20 percent of those of the reference laboratory. Results of field measurement comparisons showed larger variations among the laboratories ranging from 20 to 40 percent for C 1-C 3 carbonyl compounds. The greater variations observed in the field measurement comparison may reflect potential sampling artifacts, which the performance audits did not address.

Environmental Measurements Laboratory 2002 Unit Performance Plan

Energy Technology Data Exchange (ETDEWEB)

None

2001-10-01

This EML Unit Performance Plan provides the key goals and performance measures for FY 2002 and continuing to FY 2003. The purpose of the Plan is to inform EML's stakeholders and customers of the Laboratory's products and services, and its accomplishments and future challenges. Also incorporated in the Unit Performance Plan is EML's Communication Plan for FY 2002.

New measurements of G using the measurement standards laboratory torsion balance

International Nuclear Information System (INIS)

Armstrong, T.R.; Fitzgerald, M.P.

2003-01-01

This Letter presents the results of a series of measurements of the Newtonian gravitational constant G using the compensated torsion balance developed at the Measurement Standards Laboratory. Since our last published result using the torsion balance in the compensated mode of operation [Meas. Sci. Technol. 10, 439 (1999)], several improvements have been made to reduce the uncertainty in the final result. The new measurements have used both stainless steel and copper large masses. The values of G for the two sets of masses are in good agreement. After combining all of the measurements we get a value of G=6.673 87(0.000 27)x10 -11 m 3 kg -1 s -2 . This new value is 5 parts in 10 5 smaller than our previous published values

A Laboratory Goniometer System for Measuring Reflectance and Emittance Anisotropy

Directory of Open Access Journals (Sweden)

Arjan de Jong

2012-12-01

Full Text Available In this paper, a laboratory goniometer system for performing multi-angular measurements under controlled illumination conditions is described. A commercially available robotic arm enables the acquisition of a large number of measurements over the full hemisphere within a short time span making it much faster than other goniometers. In addition, the presented set-up enables assessment of anisotropic reflectance and emittance behaviour of soils, leaves and small canopies. Mounting a spectrometer enables acquisition of either hemispherical measurements or measurements in the horizontal plane. Mounting a thermal camera allows directional observations of the thermal emittance. This paper also presents three showcases of these different measurement set-ups in order to illustrate its possibilities. Finally, suggestions for applying this instrument and for future research directions are given, including linking the measured reflectance anisotropy with physically-based anisotropy models on the one hand and combining them with field goniometry measurements for joint analysis with remote sensing data on the other hand. The speed and flexibility of the system offer a large added value to the existing pool of laboratory goniometers.

Earth System Research Laboratory Long-Term Surface Aerosol Measurements

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Aerosol measurements began at the NOAA Earth System Research Laboratory (ESRL) Global Monitoring Division (GMD) baseline observatories in the mid-1970's with the...

Performance of the RAD-57 pulse CO-oximeter compared with standard laboratory carboxyhemoglobin measurement.

Science.gov (United States)

Touger, Michael; Birnbaum, Adrienne; Wang, Jessica; Chou, Katherine; Pearson, Darion; Bijur, Polly

2010-10-01

We assess agreement between carboxyhemoglobin levels measured by the Rad-57 signal extraction pulse CO-oximeter (RAD), a Food and Drug Administration-approved device for noninvasive bedside measurement, and standard laboratory arterial or venous measurement in a sample of emergency department (ED) patients with suspected carbon monoxide poisoning. The study was a cross-sectional cohort design using a convenience sample of adult and pediatric ED patients in a Level I trauma, burn, and hyperbaric oxygen referral center. Measurement of RAD carboxyhemoglobin was performed simultaneously with blood sampling for laboratory determination of carboxyhemoglobin level. The difference between the measures for each patient was calculated as laboratory carboxyhemoglobin minus carboxyhemoglobin from the carbon monoxide oximeter. The limits of agreement from a Bland-Altman analysis are calculated as the mean of the differences between methods ±1.96 SDs above and below the mean. Median laboratory percentage carboxyhemoglobin level was 2.3% (interquartile range 1 to 8.5; range 0% to 38%). The mean difference between laboratory carboxyhemoglobin values and RAD values was 1.4% carboxyhemoglobin (95% confidence interval [CI] 0.2% to 2.6%). The limits of agreement of differences of measurement made with the 2 devices were -11.6% and 14.4% carboxyhemoglobin. This range exceeded the value of ±5% carboxyhemoglobin defined a priori as clinically acceptable. RAD correctly identified 11 of 23 patients with laboratory values greater than 15% carboxyhemoglobin (sensitivity 48%; 95% CI 27% to 69%). There was one case of a laboratory carboxyhemoglobin level less than 15%, in which the RAD device gave a result greater than 15% (specificity of RAD 96/97=99%; 95% CI 94% to 100%). In the range of carboxyhemoglobin values measured in this sample, the level of agreement observed suggests RAD measurement may not be used interchangeably with standard laboratory measurement. Copyright © 2010 American

Environmental Measurements Laboratory program review, December 1983

International Nuclear Information System (INIS)

Volchok, H.L.; de Planque, G.

1984-03-01

This volume contains all of the written material that was submitted to the panel of Reviewers in advance of a Program Review conducted by the US Department of Energy, Office of Health and Environmental Research at the Environmental Measurements Laboratory (EML) December 7-9, 1983. In addition to a general introduction there are nineteen papers grouped into the five broad program categories covering all of the scientific and engineering projects of the Laboratory: Natural Radioactivity and Radiation, Anthropogenic Radioactivity and Radiation, Non-nuclear, Quality Assurance, and Development and Support. These short articles, for the most part, focus on the rationale for EML's involvement in each project, emphasizing their relevance to the EML and Department of Energy missions. Project results and their interpretation were presented at the Review and can be found in the material referenced in this volume

Science outside the laboratory measurement in field science and economics

CERN Document Server

Boumans, Marcel

2015-01-01

The conduct of most of social science occurs outside the laboratory. Such studies in field science explore phenomena that cannot for practical, technical, or ethical reasons be explored under controlled conditions. These phenomena cannot be fully isolated from their environment or investigated by manipulation or intervention. Yet measurement, including rigorous or clinical measurement, does provide analysts with a sound basis for discerning what occurs under field conditions, and why. In Science Outside the Laboratory, Marcel Boumans explores the state of measurement theory, its reliability, and the role expert judgment plays in field investigations from the perspective of the philosophy of science. Its discussion of the problems of passive observation, the calculus of observation, the two-model problem, and model-based consensus uses illustrations drawn primarily from economics. Rich in research and discussion, the volume clarifies the extent to which measurement provides valid information about objects an...

Dose measurements in laboratory of Physics department, University of Khartoum

International Nuclear Information System (INIS)

Hamid, Maria Mohammed

1999-05-01

Personal monitoring in University of Khartoum is being conducted using thermoluminescent dosimetry. The purpose of the study is to measure the dose of radiation in laboratory of Physics in physics department. TL phosphors LiF: Mg, Ti (card) and LiF Mg, Cu, P (GR-200) and mini-rad dosimeter are used to measure the dose in laboratory. The total dose for students form the laboratory bu using card, GR-200 and mini-rad dosimeter was found to be 2.2μ sv/year. 2.5 μ sv/year and 2.6 μ sv respectively, and for the teacher about 4.0 μ sv/year, 5.8 μ sv/year and 13.6 μ sv/year respectively, and for the dose near junk room about 3.9 μ sv/year, 2.9 μ sv/year and 2.8 μ sv/year by using card, GR-200 and mini-rad dosimeter respectively. There is just a background radiation in the main library and the applied nuclear.(Author)

Fluorescence quantum yield measurements of fluorescent proteins: a laboratory experiment for a biochemistry or molecular biophysics laboratory course.

Science.gov (United States)

Wall, Kathryn P; Dillon, Rebecca; Knowles, Michelle K

2015-01-01

Fluorescent proteins are commonly used in cell biology to assess where proteins are within a cell as a function of time and provide insight into intracellular protein function. However, the usefulness of a fluorescent protein depends directly on the quantum yield. The quantum yield relates the efficiency at which a fluorescent molecule converts absorbed photons into emitted photons and it is necessary to know for assessing what fluorescent protein is the most appropriate for a particular application. In this work, we have designed an upper-level, biochemistry laboratory experiment where students measure the fluorescence quantum yields of fluorescent proteins relative to a standard organic dye. Four fluorescent protein variants, enhanced cyan fluorescent protein (ECFP), enhanced green fluorescent protein (EGFP), mCitrine, and mCherry, were used, however the methods described are useful for the characterization of any fluorescent protein or could be expanded to fluorescent quantum yield measurements of organic dye molecules. The laboratory is designed as a guided inquiry project and takes two, 4 hr laboratory periods. During the first day students design the experiment by selecting the excitation wavelength, choosing the standard, and determining the concentration needed for the quantum yield experiment that takes place in the second laboratory period. Overall, this laboratory provides students with a guided inquiry learning experience and introduces concepts of fluorescence biophysics into a biochemistry laboratory curriculum. © 2014 The International Union of Biochemistry and Molecular Biology.

Magnetic measurements at Lawrence Berkeley Laboratory

International Nuclear Information System (INIS)

Green, M.I.; Barale, P.; Callapp, L.; Case-Fortier, M.; Lerner, D.; Nelson, D.; Schermer, R.; Skipper, G.; Van Dyke, D.; Cork, C.; Halbach, K.; Hassenzahl, W.; Hoyer, E.; Marks, S.; Harten, T.; Luchini, K.; Milburn, J.; Tanabe, J.; Zucca, F.; Keller, R.; Selph, F.; Gilbert, W.; Green, M.A.; O'Neil, J.; Schafer, R.; Taylor, C.; Greiman, W.; Hall, D.; MacFarlane, J.

1991-08-01

Recent magnetic measurement activities at LBL have been concentrated in two separate areas, electro-magnets and permanent magnets for the Advanced Light Source (ALS), and superconducting magnets for the Superconducting Super Collider Laboratory (SSCL). A survey of the many different measurement systems is presented. These include: AC magnetic measurements of an ALS booster dipole engineering model magnet, dipole moment measurements of permanent magnet blocks for ALS wigglers and undulators, permeability measurements of samples destined for wiggler and undulator poles, harmonic error analysis of SSC one meter model dipoles and quadrupoles and five meter long SSC prototype quadrupoles, harmonic error analysis of ALS dipoles, quadrupoles, and sextupoles, precision Hall probe mapping of ALS storage ring combined function magnets, and the design of the ALS insertion device magnets mapping system. We also describe a new UNIX based data acquisition system that is being developed for the SSC. Probes used for magnetic measurements include Helmholtz coils, integral coils, point coils, and bucking harmonic analysis coils, several different types of Hall probes, and nuclear magnetic resonance magnetometers. Both analog and digital integrators are used with the coils. Some problems that occurred and their rectification is described. The mechanisms used include rotating systems with optical encoders, X-Y mapping systems with optical encoders and a laser position measuring device. 10 refs., 3 figs., 1 tab

Variability of creatinine measurements in clinical laboratories: results from the CRIC study.

Science.gov (United States)

Joffe, Marshall; Hsu, Chi-yuan; Feldman, Harold I; Weir, Matthew; Landis, J R; Hamm, L Lee

2010-01-01

Estimating equations using serum creatinine (SCr) are often used to assess glomerular filtration rate (GFR). Such creatinine (Cr)-based formulae may produce biased estimates of GFR when using Cr measurements that have not been calibrated to reference laboratories. In this paper, we sought to examine the degree of this variation in Cr assays in several laboratories associated with academic medical centers affiliated with the Chronic Renal Insufficiency Cohort (CRIC) Study; to consider how best to correct for this variation, and to quantify the impact of such corrections on eligibility for participation in CRIC. Variability of Cr is of particular concern in the conduct of CRIC, a large multicenter study of subjects with chronic renal disease, because eligibility for the study depends on Cr-based assessment of GFR. A library of 5 large volume plasma specimens from apheresis patients was assembled, representing levels of plasma Cr from 0.8 to 2.4 mg/dl. Samples from this library were used for measurement of Cr at each of the 14 CRIC laboratories repetitively over time. We used graphical displays and linear regression methods to examine the variability in Cr, and used linear regression to develop calibration equations. We also examined the impact of the various calibration equations on the proportion of subjects screened as potential participants who were actually eligible for the study. There was substantial variability in Cr assays across laboratories and over time. We developed calibration equations for each laboratory; these equations varied substantially among laboratories and somewhat over time in some laboratories. The laboratory site contributed the most to variability (51% of the variance unexplained by the specimen) and variation with time accounted for another 15%. In some laboratories, calibration equations resulted in differences in eligibility for CRIC of as much as 20%. The substantial variability in SCr assays across laboratories necessitates calibration

Contributions to the FEL2005 conference

Energy Technology Data Exchange (ETDEWEB)

Grimm, O. (comp.)

2005-07-01

The following topics were dealt with: First lasing at 32 nm of the VUV-FEL at DESY, properties of the radiation from VUV-FEL at DESY, accelerator lay out and physics of X-ray free-electron lasers, bunch compression stability dependence on RF parameters, undulator systems and photon diagnostic for the European XFEL project, electron beam characterization at PITZ and the VUV-FEL at DESY, high precision optical synchronization systems for X-ray free electron lasers, optical laser synnchronized for the DESY VUV-FEL for two-color pump probe experiments, properties of the third harmonic of the SASE FEL radiation, detector response and beam line transmission measurements with far-infrared radiation, upgrades of the laser beam-line at PITZ, bunch length measurements using a Martin-Puplett interferometer at the VUV-FEL, next generation synchronization system for the VUV-FEL at DESY, transverse electron beam diagnostics at the VYV-FEL at DESY, the infrared undulator project at the VUV-FEL, misconceptions regarding second harmonic generation in X-ray free-electron lasers, influence of an energy chirp on SASE FEL operation, design considerations for the 4GLS XUV-FEL, broadband single shot spectrometer, commissioning of TTF2 bunch compressors for 20 fs SASE source, observation of femtosecond bunch length using a transverse deflecting structure, measurement of slice-emittance using a transverse deflecting structure, the injector of the VUV-FEL at DESY, spectral decoding electro-optic measurements for longitudinal bunch diagnostics at the DESY VUV-FEL, longitudinal phase space studies at PITZ, modelling the transverse phase space and core emittance studies at PITZ, measurements of thermal emittance for cesium telluride photocathodes at PITZ, status and first results from the upgraded PITZ facility, commissioning of the SPARC movable emittance meter and its first operation at PITZ. (HSI)

Contributions to the FEL2005 conference

International Nuclear Information System (INIS)

Grimm, O.

2005-01-01

The following topics were dealt with: First lasing at 32 nm of the VUV-FEL at DESY, properties of the radiation from VUV-FEL at DESY, accelerator lay out and physics of X-ray free-electron lasers, bunch compression stability dependence on RF parameters, undulator systems and photon diagnostic for the European XFEL project, electron beam characterization at PITZ and the VUV-FEL at DESY, high precision optical synchronization systems for X-ray free electron lasers, optical laser synnchronized for the DESY VUV-FEL for two-color pump probe experiments, properties of the third harmonic of the SASE FEL radiation, detector response and beam line transmission measurements with far-infrared radiation, upgrades of the laser beam-line at PITZ, bunch length measurements using a Martin-Puplett interferometer at the VUV-FEL, next generation synchronization system for the VUV-FEL at DESY, transverse electron beam diagnostics at the VYV-FEL at DESY, the infrared undulator project at the VUV-FEL, misconceptions regarding second harmonic generation in X-ray free-electron lasers, influence of an energy chirp on SASE FEL operation, design considerations for the 4GLS XUV-FEL, broadband single shot spectrometer, commissioning of TTF2 bunch compressors for 20 fs SASE source, observation of femtosecond bunch length using a transverse deflecting structure, measurement of slice-emittance using a transverse deflecting structure, the injector of the VUV-FEL at DESY, spectral decoding electro-optic measurements for longitudinal bunch diagnostics at the DESY VUV-FEL, longitudinal phase space studies at PITZ, modelling the transverse phase space and core emittance studies at PITZ, measurements of thermal emittance for cesium telluride photocathodes at PITZ, status and first results from the upgraded PITZ facility, commissioning of the SPARC movable emittance meter and its first operation at PITZ. (HSI)

VUV study of impurity generation during ICRF heating experiments on the Alcator C tokamak

International Nuclear Information System (INIS)

Manning, H.L.

1986-06-01

A 2.2 meter grazing incidence VUV monochromator has been converted into a time-resolving spectrograph by the addition of a new detector system, based on a microchannel plate image intensifier linked to a 1024-element linear photodiode array. The system covers the wavelength range 15 to 1200 A (typically 40 A at a time) with resolution of up to .3 A FWHM. Time resolution is selectable down to 0.5 msec. The system sensitivity was absolutely calibrated below 150 A by a soft x-ray calibration facility. The spectrograph was installed on the Alcator C tokamak at MIT to monitor plasma impurity emission. There, cross-calibration with a calibrated EUV monochromator was performed above 400 A. Calibration results, system performance characteristics, and data from Alcator C are presented. Observations of impurity behavior are presented from a series of ICRF heating experiments (180 MHz, 50 to 400 kW) performed on the Alcator C tokamak, using graphite limiters and stainless steel antenna Faraday shields

In-situ measurement of environment radioactivity by mobile nuclear field laboratory (MNFL)

International Nuclear Information System (INIS)

Gopalani, Deepak; Mathur, A.P.; Rawat, D.K.; Barala, S.S.; Singhal, K.P.; Singh, G.P.; Samant, R.P.

2008-01-01

In-situ measurement of environment radioactivity is useful tool for determine the unusual increase of radioactivity at any place due to any nuclear eventuality take place. A mobile nuclear field laboratory has been designed and developed for in-situ measurement of environment radioactivity at any desired location. This vehicle is equipped with different monitoring and analysis instruments. These equipment can be operated while vehicle is moving. The measured data can be stored in computer. This vehicle has the space for storage of various environmental matrices of affected area and these can analysis in laboratory. (author)

DOOCS based control system for FPGA based cavity simulator and controller in VUV FEL

International Nuclear Information System (INIS)

Pucyk, P.

2005-09-01

The X-ray free-electron laser XFEL that is being planned at the DESY research center in cooperation with European partners will produce high-intensity ultra-short X-ray flashes with the properties of laser light. This new light source, which can only be described in terms of superlatives, will open up a whole range of new perspectives for the natural sciences. It could also offer very promising opportunities for industrial users. SIMCON (SIMulator and CONtroller) is the project of the fast, low latency digital controller dedicated for LLRF 1 system in VUV FEL experiment It is being developed by ELHEP 2 group in Institute of Electronic Systems at Warsaw University of Technology. The main purpose of the project is to create a controller for stabilizing the vector sum of fields in cavities of one cryo module in the experiment. The device can be also used as the simulator of the cavity and test bench for other devices. Ths paper describes the concept, implementation and tests of the DOOCS based control system for SIMCON. The designed system is based the concept of autonomic and extendable modules connected by well defined, unified interfaces. The communication module controls the access to the hardware. It is crucial, that all modules (this presented in thesis and developed in the future) use this interface. Direct access to the control tables let the engineers to perform algorithm development or diagnostic measurements of the LLRF system. Default control tables generator makes the whole SIMCON an autonomic device, which can start immediately the operation without any additional tools. (orig.)

DOOCS based control system for FPGA based cavity simulator and controller in VUV FEL

International Nuclear Information System (INIS)

Pucyk, P.D.

2006-03-01

The X-ray free-electron laser XFEL that is being planned at the DESY research center in cooperation with European partners will produce high-intensity ultra-short X-ray flashes with the properties of laser light. This new light source, which can only be described in terms of superlatives, will open up a whole range of new perspectives for the natural sciences. It could also offer very promising opportunities for industrial users. SIMCON (SIMulator and CONtroller) is the project of the fast, low latency digital controller dedicated for LLRF 1 system in VUV FEL experiment It is being developed by ELHEP 2 group in Institute of Electronic Systems at Warsaw University of Technology. The main purpose of the project is to create a controller for stabilizing the vector sum of fields in cavities of one cryo module in the experiment. The device can be also used as the simulator of the cavity and test bench for other devices. This paper describes the concept, implementation and tests of the DOOCS based control system for SIMCON. The designed system is based the concept of autonomic and extendable modules connected by well defined, unified interfaces. The communication module controls the access to the hardware. It is crucial, that all modules (this presented in thesis and developed in the future) use this interface. Direct access to the control tables let the engineers to perform algorithm development or diagnostic measurements of the LLRF system. Default control tables generator makes the whole SIMCON an autonomic device, which can start immediately the operation without any additional tools. (Orig.)

Measuring Meaningful Learning in the Undergraduate Chemistry Laboratory: A National, Cross-Sectional Study

Science.gov (United States)

Galloway, Kelli R.; Bretz, Stacey Lowery

2015-01-01

Research on laboratory learning points to the need to better understand what and how students learn in the undergraduate chemistry laboratory. The Meaningful Learning in the Laboratory Instrument (MLLI) was administered to general and organic chemistry students from 15 colleges and universities across the United States in order to measure the…

Absolute atomic oxygen and nitrogen densities in radio-frequency driven atmospheric pressure cold plasmas: Synchrotron vacuum ultra-violet high-resolution Fourier-transform absorption measurements

International Nuclear Information System (INIS)

Niemi, K.; O'Connell, D.; Gans, T.; Oliveira, N. de; Joyeux, D.; Nahon, L.; Booth, J. P.

2013-01-01

Reactive atomic species play a key role in emerging cold atmospheric pressure plasma applications, in particular, in plasma medicine. Absolute densities of atomic oxygen and atomic nitrogen were measured in a radio-frequency driven non-equilibrium plasma operated at atmospheric pressure using vacuum ultra-violet (VUV) absorption spectroscopy. The experiment was conducted on the DESIRS synchrotron beamline using a unique VUV Fourier-transform spectrometer. Measurements were carried out in plasmas operated in helium with air-like N 2 /O 2 (4:1) admixtures. A maximum in the O-atom concentration of (9.1 ± 0.7)×10 20 m −3 was found at admixtures of 0.35 vol. %, while the N-atom concentration exhibits a maximum of (5.7 ± 0.4)×10 19 m −3 at 0.1 vol. %

Active Radiation Level Measurement on New Laboratory Instrument for Evaluating the Antibacterial Activity of Radioisotope

International Nuclear Information System (INIS)

Joh, Eunha; Park, Jang Guen

2014-01-01

A disc method has been widely used to measure the antibacterial effect of chemical agents. However, it is difficult to measure the antibacterial effect of radioisotopes using a disc method. A disc method is a method for diffusing a drug by placing the drug containing disc on the medium. In this method, radioisotopes are diffused on the medium and it is difficult to measure the exact effect by radiation. Thus, new laboratory equipment needs to evaluate the antibacterial activity by the radioisotopes. In this study, we measured the radiation level of radioisotopes on a new laboratory instrument using a MCNP. A disc method has been widely used to measure the antibacterial effect of chemical agents. This method uses a drug diffusion system for the measurement of anti-bacterial antibiotics. To measure the antimicrobial activity of a radioisotope, a new type of laboratory instrument is necessary to prevent the drug from spreading. The radioisotopes are used to diagnose and treat cancer. However, studies for anti-biotical use have not progressed. The radiation of radioisotopes has the effect of killing bacteria. Before this study proceeds further, it is necessary to be able to measure the antimicrobial activity of the radioisotope easily in the laboratory. However, in this study, it was possible to measure the antimicrobial activity of the radioisotope in the laboratory using a new laboratory instrument. We intend to start evaluation studies of the antibacterial activity of specific radioisotopes. In addition, it will be possible to develop research to overcome diseases caused by bacteria in the future

Active Radiation Level Measurement on New Laboratory Instrument for Evaluating the Antibacterial Activity of Radioisotope

Energy Technology Data Exchange (ETDEWEB)

Joh, Eunha; Park, Jang Guen [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-05-15

A disc method has been widely used to measure the antibacterial effect of chemical agents. However, it is difficult to measure the antibacterial effect of radioisotopes using a disc method. A disc method is a method for diffusing a drug by placing the drug containing disc on the medium. In this method, radioisotopes are diffused on the medium and it is difficult to measure the exact effect by radiation. Thus, new laboratory equipment needs to evaluate the antibacterial activity by the radioisotopes. In this study, we measured the radiation level of radioisotopes on a new laboratory instrument using a MCNP. A disc method has been widely used to measure the antibacterial effect of chemical agents. This method uses a drug diffusion system for the measurement of anti-bacterial antibiotics. To measure the antimicrobial activity of a radioisotope, a new type of laboratory instrument is necessary to prevent the drug from spreading. The radioisotopes are used to diagnose and treat cancer. However, studies for anti-biotical use have not progressed. The radiation of radioisotopes has the effect of killing bacteria. Before this study proceeds further, it is necessary to be able to measure the antimicrobial activity of the radioisotope easily in the laboratory. However, in this study, it was possible to measure the antimicrobial activity of the radioisotope in the laboratory using a new laboratory instrument. We intend to start evaluation studies of the antibacterial activity of specific radioisotopes. In addition, it will be possible to develop research to overcome diseases caused by bacteria in the future.

Laser-plasma sourced, temperature dependent, VUV spectrophotometer using dispersive analysis

International Nuclear Information System (INIS)

French, R.H.

1990-01-01

We have developed a vacuum ultraviolet spectrophotometer with wide energy and temperature range coverage, utilizing a laser-plasma light source (LPLS), CO 2 -laser sample heating and time-resolved dispersive analysis. Reflection and transmission spectra can be taken from 1.7 to 40 eV (31-700 nm) on samples at 15-1800 K with a time resolution of 20-400 ns. These capabilities permit the study of the temperature dependence of the electronic structure, encompassing the effects of thermal lattice expansion and electron-phonon interaction, and changes in the electronic structure associated with equilibrium and metastable phase transitions and stress relaxation. The LPLS utilizes a samarium laser-plasma created by a Q-switched Nd:YAG laser (500 mJ/pulse) to produce high brightness, stable, continuum radiation. The spectrophotometer is of a single beam design using calibrated iridium reference mirrors. White light is imaged off the sample in to the entrance slit of a 1-m polychromator. The resolution is 0.1 to 0.3 nm. The dispersed light is incident on a focal plane phosphor, fiber-optic-coupled to an image-intensified reticon detector. For spectroscopy between 300 and 1800 K, the samples are heated in situ with a 150 Watt CO 2 laser. The signal to noise ratio in the VUV, for samples at 1800 K, is excellent. From 300 K to 15 K samples are cooled using a He cryostat. (orig.)

Methods of Estimation the Reliability and Increasing the Informativeness of the Laboratory Results (Analysis of the Laboratory Case of Measurement the Indicators of Thyroid Function

Directory of Open Access Journals (Sweden)

N A Kovyazina

2014-06-01

Full Text Available The goal of the study was to demonstrate the multilevel laboratory quality management system and point at the methods of estimating the reliability and increasing the amount of information content of the laboratory results (on the example of the laboratory case. Results. The article examines the stages of laboratory quality management which has helped to estimate the reliability of the results of determining Free T3, Free T4 and TSH. The measurement results are presented by the expanded uncertainty and the evaluation of the dynamics. Conclusion. Compliance with mandatory measures for laboratory quality management system enables laboratories to obtain reliable results and calculate the parameters that are able to increase the amount of information content of laboratory tests in clinical decision making.

Verification of Electromagnetic Field Measurements via Inter-laboratory Comparison Measurements

Directory of Open Access Journals (Sweden)

M. Mann

2005-01-01

Full Text Available An inter-laboratory comparison of field strength measurements was conducted in order to verify the comparability of high-frequency electromagnetic field measurements. For this purpose, 17 participating teams hosted by the working group "procedures of exposure determination" of the LAI (Länderausschuss für Immissionsschutz, state committee on immission control determined the field strength at given stations around a hospital situation. At those stations very different signals were generated, such as sine wave signals at 27MHz and 433MHz, signals from a diathermy device in Continuous-Wave (CW and Pulse-Width-Modulation (PWM mode, from a GSM base station at 900MHz and 1800MHz, from a UMTS base station, from a babyphone device and from a DECT cordless phone. This contribution describes the evaluation of the measured values and the approach to the computation of a reference value. Considering various sources of electromagnetic fields in the areas of personal safety at work and of immission control, the most important results are presented and the conclusions drawn are discussed.

A laboratory experimental setup for photo-absorption studies using synchrotron radiation

CERN Document Server

Shastri, A; Saraswati, P; Sunanda, K

2002-01-01

The photophysics beamline, which is being installed at the 450 MeV Synchrotron Radiation Source (SRS), Indus-l, is a medium resolution beamline useful for a variety of experiments in the VUV region viz. 500-2000 A. One of the major applications of this beamline is gas-phase photo-absorption studies. An experimental set up to be used for these experiments was designed, developed and tested in our laboratory. The setup consists of a high vacuum absorption cell, 1/4 m monochromator and detection system. For the purpose of testing, xenon and tungsten continuum sources were used and absorption spectra were recorded in the UV region. This setup was used to record the absorption spectrum of a few molecules like acetone, ammonia, benzene, formaldehyde and acetaldehyde in order to evaluate the performance of the experimental system which will subsequently be used with the photophysics beamline. Details of the design, fabrication and testing of the absorption cell and experimental procedures are presented in this repor...

Laboratory Measurements of Optical Properties of Micron Size Individual Dust Grains

Science.gov (United States)

Abbas, M. M.; Craven, P. D.; Spann, J. F.; Tankosic, D.; LeClair, A.; Witherow, W. K.; Camata, R.; Gerakines, P.

2003-01-01

A laboratory program is being developed at NASA Marshall Space Flight Center for experimental determination of the optical and physical properties individual dust grains in simulated astrophysical environments. The experimental setup is based on an electrodynamic balance that permits levitation of single 0.1 - 10 micron radii dust grains in a cavity evacuated to pressures of approx. 10(exp -6) torr. The experimental apparatus is equipped with observational ports for measurements in the UV, visible, and infrared spectral regions. A cryogenic facility for cooling the particles to temperature of approx. 10-50K is being installed. The current and the planned measurements include: dust charging processes, photoelectric emissions and yields with UV irradiation, radiation pressure measurements, infrared absorption and scattering properties, and condensation processes, involving the analogs of cosmic dust grains. Selected results based on photoemissions, radiation pressure, and other laboratory measurements will be presented.

The spectral characteristics of Gd sub 2 SiO sub 5 :Eu sup 3 sup + in VUV-UV range

CERN Document Server

Chen Yong; Wei Ya Guang; Tao Ye

2002-01-01

Synchrotron radiation source was used to investigated the spectral characteristics of Gd sub 2 SiO sub 5 :Eu sup 3 sup + in VUV-UV range. The various energy transfers at room temperature and 10 K, including from host or Gd sup 3 sup + ions to Eu sup 3 sup + ions and transfer between Eu sup 3 sup + ions at two different lattice sites, were discussed. In addition the emission spectra under 186 nm and 276 nm excitation were compared from the view of quantum cutting. The results indicate that Gd sub 2 SiO sub 5 :Eu sup 3 sup + is a kind of material with potential high efficiency quantum cutting

Impact of a do-not-do intervention on 12 laboratory measurements.

Science.gov (United States)

Zambrana-García, J L; Macías Blanco, C; Fernández-Suárez, A; Peñacoba Masa, A; Olivares Durán, M J; Aguilar Benítez, J M; Zambrana-Luque, J L

2017-11-01

In recent years, various scientific societies and healthcare organisations have created recommendations aimed at decreasing the use of healthcare interventions that have shown no efficacy or effectiveness. The aim of this study was to assess the impact of an intervention on 12 do-not-do recommendations regarding the laboratory in 7 hospital centres. Before-after study conducted in 7 hospital centres of Cordoba and Jaen during 2015 and 2016. Based on the recommendations of existing scientific societies, a consensus was reached on various actions regarding laboratory measurements. We analysed the number and cost of measuring 6 tumour markers (carcinoembryonic antigen, prostate-specific antigen, carbohydrate antigen [CA] 15.3, CA125, CA19.9 and alpha-fetoprotein), thyrotropin, T3, T4, glycated haemoglobin, urea, ferritin and antigliadin antibodies, before and after implementing the consensus. Compared with the previous year, there were 55,902 fewer laboratory measurements (-19%) in 2016, with an overall savings of €82,100. The reduction in the number of measurements occurred mainly in plasma urea (-50.3%) and in the tumour markers CA125 (-16%), CA19.9 (-11.6%) and CA15.3 (-10.5%). The most pronounced savings were achieved in the measurements of urea (-€21,002), thyroid hormones (-€12,716) and thyrotropin (-€7,638). The adoption and consensus of do-not-do recommendations among healthcare levels resulted in a significant reduction in unnecessary measurements. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Medicina Interna (SEMI). All rights reserved.

Best practice guide for radioactivity measurement laboratories in a post-accident situation

International Nuclear Information System (INIS)

2011-01-01

Published for laboratories likely to be asked to perform radioactivity measurements at the time of or after a radiological or nuclear accident in France or abroad, this guide aims at defining the best practices in terms of laboratory organisation (sample flow management, personnel radioprotection, sample identification and recording, sample cross-contamination risks, result transmission, archiving of data, results and samples, waste dismissal), and in terms of metrology (adaptation to needs in terms of detection limit and measurement uncertainty, preferred use of gamma spectrometry, analysis strategies)

National synchrotron light source. Activity report, October 1, 1994--September 30, 1995

Energy Technology Data Exchange (ETDEWEB)

Rothman, E.Z.; Hastings, J. [eds.

1996-05-01

This report discusses research conducted at the National Synchrotron Light Source in the following areas: atomic and molecular science; energy dispersive diffraction; lithography, microscopy, and tomography; nuclear physics; scattering and crystallography studies of biological materials; time resolved spectroscopy; UV photoemission and surface science; x-ray absorption spectroscopy; x-ray scattering and crystallography; x-ray topography; the 1995 NSLS annual users` meeting; 17th international free electron laser conference; micro bunches workshop; VUV machine; VUV storage ring parameters; beamline technical improvements; x-ray beamlines; x-ray storage ring parameters; the NSLS source development laboratory; the accelerator test facility (ATF); NSLS facility improvements; NSLS advisory committees; NSLS staff; VUV beamline guide; and x-ray beamline guide.

National synchrotron light source. Activity report, October 1, 1994--September 30, 1995

International Nuclear Information System (INIS)

Rothman, E.Z.; Hastings, J.

1996-05-01

This report discusses research conducted at the National Synchrotron Light Source in the following areas: atomic and molecular science; energy dispersive diffraction; lithography, microscopy, and tomography; nuclear physics; scattering and crystallography studies of biological materials; time resolved spectroscopy; UV photoemission and surface science; x-ray absorption spectroscopy; x-ray scattering and crystallography; x-ray topography; the 1995 NSLS annual users' meeting; 17th international free electron laser conference; micro bunches workshop; VUV machine; VUV storage ring parameters; beamline technical improvements; x-ray beamlines; x-ray storage ring parameters; the NSLS source development laboratory; the accelerator test facility (ATF); NSLS facility improvements; NSLS advisory committees; NSLS staff; VUV beamline guide; and x-ray beamline guide

Development of performance assessment instrument based contextual learning for measuring students laboratory skills

Science.gov (United States)

Susilaningsih, E.; Khotimah, K.; Nurhayati, S.

2018-04-01

The assessment of laboratory skill in general hasn’t specific guideline in assessment, while the individual assessment of students during a performance and skill in performing laboratory is still not been observed and measured properly. Alternative assessment that can be used to measure student laboratory skill is use performance assessment. The purpose of this study was to determine whether the performance assessment instrument that the result of research can be used to assess basic skills student laboratory. This research was conducted by the Research and Development. The result of the data analysis performance assessment instruments developed feasible to implement and validation result 62.5 with very good categories for observation sheets laboratory skills and all of the components with the very good category. The procedure is the preliminary stages of research and development stages. Preliminary stages are divided in two, namely the field studies and literature studies. The development stages are divided into several parts, namely 1) development of the type instrument, 2) validation by an expert, 3) a limited scale trial, 4) large-scale trials and 5) implementation of the product. The instrument included in the category of effective because 26 from 29 students have very high laboratory skill and high laboratory skill. The research of performance assessment instrument is standard and can be used to assess basic skill student laboratory.

Vacuum-ultraviolet (VUV) photoionization of small methanol and methanol-water clusters

International Nuclear Information System (INIS)

Ahmed, Musahid; Ahmed, Musahid; Wilson, Kevin R.; Belau, Leonid; Kostko, Oleg

2008-01-01

In this work we report on the vacuum-ultraviolet (VUV) photoionization of small methanol and methanol-water clusters. Clusters of methanol with water are generated via co-expansion of the gas phase constituents in a continuous supersonic jet expansion of methanol and water seeded in Ar. The resulting clusters are investigated by single photon ionization with tunable vacuum ultraviolet synchrotron radiation and mass analyzed using reflectron mass spectrometry. Protonated methanol clusters of the form (CH3OH)nH + (n=1-12) dominate the mass spectrum below the ionization energy of the methanol monomer. With an increase in water concentration, small amounts of mixed clusters of the form (CH3OH)n(H2O)H + (n=2-11) are detected. The only unprotonated species observed in this work are the methanol monomer and dimer. Appearance energies are obtained from the photoionization efficiency (PIE) curves for CH3OH +, (CH 3OH)2 +, (CH3OH)nH + (n=1-9), and (CH 3OH)n(H2O)H + (n=2-9 ) as a function of photon energy. With an increase in the water content in the molecular beam, there is an enhancement of photoionization intensity for methanol dimer and protonated methanol monomer at threshold. These results are compared and contrasted to previous experimental observations

Laboratory Measured Behavioral Impulsivity Relates to Suicide Attempt History

Science.gov (United States)

Dougherty, Donald M.; Mathias, Charles W.; Marsh, Dawn M.; Papageorgiou, T. Dorina; Swann, Alan C.; Moeller, F. Gerard

2004-01-01

The purpose of this study was to examine the relationship between laboratory behavioral measured impulsivity (using the Immediate and Delayed Memory Tasks) and suicidal attempt histories. Three groups of adults were recruited, those with either: no previous suicide attempts (Control, n = 20), only a single suicide attempt (Single, n = 20), or…

Measuring the opacity of stellar interior matter in terrestrial laboratories

Science.gov (United States)

Bailey, James

2015-11-01

How does energy propagate from the core to the surface of the Sun, where it emerges to warm the Earth? Nearly a century ago Eddington recognized that the attenuation of radiation by stellar matter controls the internal structure of stars like the sun. Opacities for high energy density (HED) matter are challenging to calculate because accurate and complete descriptions of the energy levels, populations, and plasma effects such as continuum lowering and line broadening are needed for partially ionized atoms. This requires approximations, in part because billions of bound-bound and bound-free electronic transitions can contribute to the opacity. Opacity calculations, however, have never been benchmarked against laboratory measurements at stellar interior conditions. Laboratory opacity measurements were limited in the past by the challenges of creating and diagnosing sufficiently large and uniform samples at the extreme conditions found inside stars. In research conducted over more than 10 years, we developed an experimental platform on the Z facility and measured wavelength-resolved iron opacity at electron temperatures Te = 156-195 eV and densities ne = 0.7-4.0 x 1022 cm-3 - conditions very similar to the radiation/convection boundary zone within the Sun. The wavelength-dependent opacity in the 975-1775 eV photon energy range is 30-400% higher than models predict. This raises questions about how well we understand the behavior of atoms in HED plasma. These measurements may also help resolve decade-old discrepancies between solar model predictions and helioseismic observations. This talk will provide an overview of the measurements, investigations of possible errors, and ongoing experiments aimed at testing hypotheses to resolve the model-data discrepancy. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under contract DE-AC04-94AL85000.

Measurements of the background noise gamma at the Modane underground laboratory

International Nuclear Information System (INIS)

Morales, A.; Morales, J.; Nunez-Lagos, R.; Villar, J.A.

1985-01-01

Experimental measurements of the background have been performed at the Modane underground laboratory, in the Frejus tunnel, in order to locate here a neutrinoless double beta decay on 76 Ge experiment. The background reduction relative to the sea level laboratory at Bordeaux is studied, as well as the intrinsic radiactivity the INa and F 2 Ba scintillators to be selected as a 4 coincidence crown for the experiment. (author)

MgII Linear Polarization Measurements Using the MSFC Solar Ultraviolet Magnetograph

Science.gov (United States)

West, Edward; Cirtain, Jonathan; Kobayahsi, Ken; Davis, John; Gary, Allen; Adams, Mitzi

2011-01-01

This paper will describe the Marshall Space Flight Center's Solar Ultraviolet Magnetograph (SUMI) sounding rocket program, with emphasis on the polarization characteristics of the VUV optics and their spectral, spatial and polarization resolution. SUMI's first flight (7/30/2010) met all of its mission success criteria and this paper will describe the data that was acquired with emphasis on the MgII linear polarization measurements.

Variability in baseline laboratory measurements of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

Science.gov (United States)

Ladwig, R; Vigo, A; Fedeli, L M G; Chambless, L E; Bensenor, I; Schmidt, M I; Vidigal, P G; Castilhos, C D; Duncan, B B

2016-08-01

Multi-center epidemiological studies must ascertain that their measurements are accurate and reliable. For laboratory measurements, reliability can be assessed through investigation of reproducibility of measurements in the same individual. In this paper, we present results from the quality control analysis of the baseline laboratory measurements from the ELSA-Brasil study. The study enrolled 15,105 civil servants at 6 research centers in 3 regions of Brazil between 2008-2010, with multiple biochemical analytes being measured at a central laboratory. Quality control was ascertained through standard laboratory evaluation of intra- and inter-assay variability and test-retest analysis in a subset of randomly chosen participants. An additional sample of urine or blood was collected from these participants, and these samples were handled in the same manner as the original ones, locally and at the central laboratory. Reliability was assessed with the intraclass correlation coefficient (ICC), estimated through a random effects model. Coefficients of variation (CV) and Bland-Altman plots were additionally used to assess measurement variability. Laboratory intra and inter-assay CVs varied from 0.86% to 7.77%. From test-retest analyses, the ICCs were high for the majority of the analytes. Notably lower ICCs were observed for serum sodium (ICC=0.50; 95%CI=0.31-0.65) and serum potassium (ICC=0.73; 95%CI=0.60-0.83), due to the small biological range of these analytes. The CVs ranged from 1 to 14%. The Bland-Altman plots confirmed these results. The quality control analyses showed that the collection, processing and measurement protocols utilized in the ELSA-Brasil produced reliable biochemical measurements.

Neutron background measurements in the underground laboratory of Modane

International Nuclear Information System (INIS)

Chazal, V.; Chambon, B.; De Jesus, M.; Drain, D.; Pastor, C.; Vagneron, L.; Brissot, R.; Cavaignac, J.F.; Stutz, A.; Giraud-Heraud, Y.

1997-07-01

Measurements of the background neutron environment, at a depth of 1780 m (4800 mWe) in the Underground Laboratory of Modane (L.S.M) are reported. Using a 6 Li liquid scintillator, the energy spectrum of the fast neutron flux has been determined. Monte-Carlo calculations of the (α,n) and spontaneous fission processes in the surrounding rock has been performed and compared to the experimental result. In addition, using two 3 He neutron counters, the thermal neutron flux has been measured. (author)

A tool for symmetry studies in circular machines

International Nuclear Information System (INIS)

Bozoki, E.

1988-05-01

The use of the C [mrad/Amp] conversion factors of the orbit corrector magnets in the sudy of the symmetry properties of a circular accelerator or storage ring, and in the determination of the ratios of the β-functions at corrector locations is discussed. Measurements obtained for the VUV and x-ray rings of the NSLS at Brookhaven National Laboratory are presented. 4 refs., 7 figs., 3 tabs

Interaction of VUV-photons with molecules. Spectroscopy and dynamics of molecular superexcited states

International Nuclear Information System (INIS)

Hatano, Y.

2002-01-01

Complete text of publication follows. A survey is given of recent progress in experimental studies of the interaction of VUV-photons with molecules, i.e., those of photoabsorption, photoionization, and photodissociation of molecules in the excitation photon energy range of 10-50 eV, with a particular emphasis placed on current understanding of the spectroscopy and dynamics of formed molecular superexcited states. These studies are of great importance in understanding the interaction of ionizing radiation with matter. Molecules studied are ranged from simple diatomic and triatomic molecules to polyatomic molecules such as hydrocarbons. Most of the observed molecular superexcited states are assigned to high Rydber states which are vibrationally, doubly, or inner-core excited and converge to each of ion states. Non-Rydberg superexcited states are also observed. Dissociation into neutral fragments in comparison with ionization is of unexpectedly great importance in the observed decay of each of these state-assigned superexcited molecules. Dissociation dynamics as well as its products of superexcited states are remarkably different from those of lower excited states below about ionization thresholds. Some remarks are also presented of molecules in the condensed phase

The Gran Sasso underground laboratories (measurements of rock radioactivity and neutron fluxes)

International Nuclear Information System (INIS)

Bellotti, E.; Buraschi, M.; Fiorini, E.; Liguori, C.

1985-01-01

The authors report on measurements of rock radioactivity and neutron flux performed in the Gran Sasso underground laboratories of the INFN in Italy. The Gran Sasso' Laboratories of the INFN are located underground, in galleries which have been excavated under the Gran Sasso mountain range. The minimum rock thickness covering the laboratories is about 1400 m of rock of average density 2.8 g cm/sup -3/, corresponding to a thickness of some 4000 m of water equivalent. The laboratories are located at about 1000 m above sea level. The main destination of these laboratories is to shelter very huge particle detectors which shall detect extremely rare nuclear events of extraordinary interest for particle physics as well as for astrophysics and cosmology. In these laboratories, the radiation background is expected to be extremely low, which is the main condition for performing the proposed experiments

Measurement of the gravitational constant in an orbiting laboratory

Energy Technology Data Exchange (ETDEWEB)

Farinella, P [Osservatorio Astronomico di Merate, Milan (Italy); Milani, A [Pisa Univ. (Italy). Ist. di Matematica; Nobili, A M [Pisa Univ. (Italy). Ist. di Scienze dell' Informazione

1980-12-01

We propose to measure the gravitational constant G by putting in an orbiting laboratory a known mass of very high density and by tracking the motion of a small test mass under the gravitational influence of the primary mass. We analyze the different sources of perturbation: the consideration of the Earth's gravity gradient leads us to conclude that, if the laboratory is in a low Earth orbit, we cannot get stable satellite-like orbits of the test mass, but we must study only a process of gravitational scattering. In order to maximize the time of interaction it is proposed to use the practical stability of a collinear equilibrium point of the system Earth-primary mass, by putting the test mass as close as possible to the stable manifold of an equilibrium point. This method will allow the determination of the value of G withing a few parts over 10/sup 5/ as shown by some computer simulations of the experiment taking into account also some unknown perturbation and random noise. Two main problems are involved in this experiment: (a) refined numerical methods are needed to take into account all significant perturbations and to extract the result about G from the experimental data; (b) during the motion of the test mass, the primary mass must always be free-falling inside the laboratory, so that this experiment needs a drag-free satellite technique of the same type which is necessary for high-precision gravimetric measurement.

Characteristics of a nanosecond-barrier-discharge-pumped multiwave UV – VUV lamp on a mixture of argon, krypton and vapours of freon

Energy Technology Data Exchange (ETDEWEB)

Shuaibov, A K; Minya, A I; Hrytsak, R V; Gomoki, Z T [Uzhgorod National University, Uzhgorod (Ukraine)

2015-02-28

We present the results of investigation of the characteristics of a nanosecond-barrier-discharge-pumped multiwave lamp based on a gas mixture of Ar – Kr – CCl{sub 4}, which emits in the spectral range of 170 – 260 nm. The main emission bands in the lamp spectrum are ArCl (B → X) near 175 nm, KrCl (B → X) near 222 nm and Cl{sub 2} (D' → A') near 258 nm. The lamp intensity with respect to pressure, working mixture composition and pump regime is optimised. (uv - vuv emitters)

Laboratory Measurements of Particulate Matter Concentrations from Asphalt Pavement Abrasion

Directory of Open Access Journals (Sweden)

Fullová Daša

2016-12-01

Full Text Available The issue of emissions from road traffic is compounded by the fact that the number of vehicles and driven kilometres increase each year. Road traffic is one of the main sources of particulate matter and traffic volume is still increasing and has unpleasant impact on longevity of the pavements and the environment. Vehicle motions cause mechanical wearing of the asphalt pavement surface - wearing course by vehicle tyres. The contribution deals with abrasion of bituminous wearing courses of pavements. The asphalt mixtures of wearing courses are compared in terms of mechanically separated particulate matter. The samples of asphalt mixtures were rutted in wheel tracking machine. The particulate matter measurements were performed in laboratory conditions. The experimental laboratory measurements make it possible to sample particulates without contamination from exhaust emissions, abraded particles from vehicles, resuspension of road dust and climate affects. The contribution offers partial results of measurements on six trial samples of asphalt mixtures with different composition. It presents particulate matter morphology and the comparison of rutted asphalt samples in terms of PM mass concentrations and chemical composition.

Precise turnaround time measurement of laboratory processes using radiofrequency identification technology.

Science.gov (United States)

Mayer, Horst; Brümmer, Jens; Brinkmann, Thomas

2011-01-01

To implement Lean Six Sigma in our central laboratory we conducted a project to measure single pre-analytical steps influencing turnaround time (TAT) of emergency department (ED) serum samples. The traditional approach of extracting data from the Laboratory Information System (LIS) for a retrospective calculation of a mean TAT is not suitable. Therefore, we used radiofrequency identification (RFID) chips for real time tracking of individual samples at any pre-analytical step. 1,200 serum tubes were labelled with RFID chips and were provided to the emergency department. 3 RFID receivers were installed in the laboratory: at the outlet of the pneumatic tube system, at the centrifuge, and in the analyser area. In addition, time stamps of sample entry at the automated sample distributor and communication of results from the analyser were collected from LIS. 1,023 labelled serum tubes arrived at our laboratory. 899 RFID tags were used for TAT calculation. The following transfer times were determined (median 95th percentile in min:sec): pneumatic tube system --> centrifuge (01:25/04:48), centrifuge --> sample distributor (14:06/5:33), sample distributor --> analysis system zone (02:39/15:07), analysis system zone --> result communication (12:42/22:21). Total TAT was calculated at 33:19/57:40 min:sec. Manual processes around centrifugation were identified as a major part of TAT with 44%/60% (median/95th percentile). RFID is a robust, easy to use, and error-free technology and not susceptible to interferences in the laboratory environment. With this study design we were able to measure significant variations in a single manual sample transfer process. We showed that TAT is mainly influenced by manual steps around the centrifugation process and we concluded that centrifugation should be integrated in solutions for total laboratory automation.

The New Brunswick Laboratory Safeguards Measurement Evaluation Program

International Nuclear Information System (INIS)

Cacic, C.G.; Trahey, N.M.; Zook, A.C.

1987-01-01

The New Brunswick Laboratory (NBL) has been tasked by the U.S. Department of Energy (DOE) Office of Safeguards and Security (OSS) to assess and evaluate the adequacy of measurement technology as applied to materials accounting in DOE nuclear facilities. The Safeguards Measurement Evaluation (SME) Program was developed as a means to monitor and evaluate the quality and effectiveness of accounting measurements by site, material balance area (MBA), or unit process. Phase I of the SME Program, initiated during 1985, involved evaluation of the primary accountability measurement methods at six DOE Defense Programs facilities: Savannah River Plant, Portsmouth Gaseous Diffusion Plant, Y-12 Plant, Rocky Flats Plant, Rockwell Hanford Operations, and NBL. Samples of uranyl nitrate solution, dried plutonium nitrates, and plutonium oxides were shipped to the participants for assay and isotopic abundance measurements. Resulting data are presented and evaluated as indicators of current state-of-the-practice accountability measurement methodology, deficiencies in materials accounting practices, and areas for possible assistance in upgrading measurement capabilities. Continuing expansion of the SME Program to include materials which are representative of specific accountability measurement points within the DOE complex is discussed

Laboratory measurements and astronomical search for cyanomethanimine

Science.gov (United States)

Melosso, M.; Melli, A.; Puzzarini, C.; Codella, C.; Spada, L.; Dore, L.; Degli Esposti, C.; Lefloch, B.; Bachiller, R.; Ceccarelli, C.; Cernicharo, J.; Barone, V.

2018-02-01

Context. C-cyanomethanimine (HNCHCN), existing in the two Z and E isomeric forms, is a key prebiotic molecule, but, so far, only the E isomer has been detected toward the massive star-forming region Sagittarius B2(N) using transitions in the radio wavelength domain. Aims: With the aim of detecting HNCHCN in Sun-like-star forming regions, the laboratory investigation of its rotational spectrum has been extended to the millimeter-/submillimeter-wave (mm-/submm-) spectral window in which several unbiased spectral surveys have been already carried out. Methods: High-resolution laboratory measurements of the rotational spectrum of C-cyanomethanimine were carried out in the 100-420 GHz range using a frequency-modulation absorption spectrometer. We then searched for the C-cyanomethanimine spectral features in the mm-wave range using the high-sensitivity and unbiased spectral surveys obtained with the IRAM 30-m antenna in the ASAI context, the earliest stages of star formation from starless to evolved Class I objects being sampled. Results: For both the Z and E isomers, the spectroscopic work has led to an improved and extended knowledge of the spectroscopic parameters, thus providing accurate predictions of the rotational signatures up to 700 GHz. So far, no C-cyanomethanimine emission has been detected toward the ASAI targets, and upper limits of the column density of 1011-1012 cm-2 could only be derived. Consequently, the C-cyanomethanimine abundances have to be less than a few 10-10 for starless and hot-corinos. A less stringent constraint, ≤10-9, is obtained for shocks sites. Conclusions: The combination of the upper limits of the abundances of C-cyanomethanimine together with accurate laboratory frequencies up to 700 GHz poses the basis for future higher sensitivity searches around Sun-like-star forming regions. For compact (typically less than 1″) and chemically enriched sources such as hot-corinos, the use of interferometers as NOEMA and ALMA in their extended

Measurements of VUV lines on dense Z-pinch plasma

International Nuclear Information System (INIS)

Bertschinger, G.

1980-01-01

The transition n = 1 to n = 2 has the most simple structure of all hydrogen transitions and the corresponding spectralline Ly-α is therefore very appropriate to reveal discrepancies between theory and experiment. In this work mainly the Ly-α spectral line of neutral hydrogen has been studied. The electron density of the Z-pinch amounts to 1.5 x 10 24 m -3 with an electron temperature of about 1.2 x 10 5 K. In this parameter range the plasma can still be studied with spectroscopic methods in the visible spectral region. Based on a space and time resolved measurement of the continuous emission spectra the plasma parameters can be determined independent of line broadening. (orig./HT) [de

The performance test of NAA laboratory at radionuclide measure with low activity

International Nuclear Information System (INIS)

Sri Murniasih; Sukirno

2016-01-01

The performance test to measure the I-131 radionuclide activity has been carried out at CAST-NAA laboratory. The purpose of this activity is to know the performance of a laboratory in the testing of low radioactivity sample. The tested sample consists of the form I-131 radionuclide sources shaped thin plastic disk with a certain weight. Evaluation of laboratory performance test results carried out by the organizer of the program test appeal (PTKMR-BATAN). Evaluation results showed that testing of point source of the I-131 radionuclide with comparative method gives a good enough results with errors below 10%. The results of the performance test evaluation are useful as the external quality control to a testing method that is expected in NAA laboratory. (author)

VUV-UV–vis photoluminescence of Ce{sup 3+} and Ce{sup 3+}-Eu{sup 2+} energy transfer in Ba{sub 2}MgSi{sub 2}O{sub 7}

Energy Technology Data Exchange (ETDEWEB)

Yan, Jing; Liu, Chunmeng; Zhou, Weijie [MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou 510275 (China); Huang, Yan; Tao, Ye [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100039 (China); Liang, Hongbin, E-mail: cesbin@mail.sysu.edu.cn [MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou 510275 (China)

2017-05-15

A series of Ce{sup 3+} doped and Ce{sup 3+}-Eu{sup 2+} co-doped Ba{sub 2}MgSi{sub 2}O{sub 7} phosphors was prepared via a high-temperature solid-state reaction technique. The photoluminescence properties, which include synchrotron radiation VUV-UV excitation spectra, emission spectra and concentration effect, thermal stability of Ce{sup 3+} are investigated. Hence the energies of the crystal field split 5d excited states of Ce{sup 3+} are determined. Due to spectral overlap, the energy transfer from sensitizer Ce{sup 3+} to activator Eu{sup 2+} in Ba{sub 2}MgSi{sub 2}O{sub 7}:Ce{sup 3+}, Eu{sup 2+} occurs, and the mechanism is demonstrated to be an electric dipole−dipole interaction. - Highlights: •The energies of five crystal field split 5d states of Ce{sup 3+} in Ba{sub 2}MgSi{sub 2}O{sub 7} were determined by synchrotron radiation VUV-UV excitation spectrum. •The concentration effect, thermal stability of Ce{sup 3+} were investigated. •The energy transfer from Ce{sup 3+} to Eu{sup 2+} and its influence on luminescence decays of Ce{sup 3+} and Eu{sup 2+} were studied.

Measuring Meaningful Learning in the Undergraduate General Chemistry and Organic Chemistry Laboratories: A Longitudinal Study

Science.gov (United States)

Galloway, Kelli R.; Bretz, Stacey Lowery

2015-01-01

Understanding how students learn in the undergraduate chemistry teaching laboratory is an essential component to developing evidence-based laboratory curricula. The Meaningful Learning in the Laboratory Instrument (MLLI) was developed to measure students' cognitive and affective expectations and experiences for learning in the chemistry…

Correction of stream quality trends for the effects of laboratory measurement bias

Science.gov (United States)

Alexander, Richard B.; Smith, Richard A.; Schwarz, Gregory E.

1993-01-01

We present a statistical model relating measurements of water quality to associated errors in laboratory methods. Estimation of the model allows us to correct trends in water quality for long-term and short-term variations in laboratory measurement errors. An illustration of the bias correction method for a large national set of stream water quality and quality assurance data shows that reductions in the bias of estimates of water quality trend slopes are achieved at the expense of increases in the variance of these estimates. Slight improvements occur in the precision of estimates of trend in bias by using correlative information on bias and water quality to estimate random variations in measurement bias. The results of this investigation stress the need for reliable, long-term quality assurance data and efficient statistical methods to assess the effects of measurement errors on the detection of water quality trends.

Characterization of Orbital Debris Photometric Properties Derived from Laboratory-Based Measurements

Science.gov (United States)

Cowardin, H.; Abercromby, K.; Barker, E.; Seitzer, P.; Schildknecht, T.

2010-01-01

To better characterize and model optical data acquired from ground-based telescopes, the Optical Measurements Center (OMC) at NASA/JSC attempts to emulate illumination conditions seen in space using equipment and techniques that parallel telescopic observations and source-target-sensor orientations. The OMC uses a 75 Watt Xenon arc lamp as a solar simulator, an SBIG CCD camera with standard Johnson/Bessel filters, and a robotic arm to simulate an object's position and rotation. The laboratory uses known shapes, materials suspected to be consistent with the orbital debris population, and three phase angles to best match the lighting conditions of the telescope based data. The fourteen objects studied in the laboratory are fragments or materials acquired through ground-tests of scaled-model satellites/rocket bodies as well as material samples in more/less "flight-ready" condition. All fragments were measured at 10 increments in a full 360 rotation at 6 , 36 , and 60 phase angles. This paper will investigate published color photometric data for a series of orbital debris targets and compare it to the empirical photometric measurements generated in the OMC. Using the data acquired over specific rotational angles through different filters (B, V, R, I), a color index is acquired (B-R, R-I). Using these values and their associated lightcurves, this laboratory data is compared to observational data obtained on the 1 m telescope of the Astronomical Institute of the University of Bern (AUIB), the 0.9 m operated by the Small- and Medium-Aperture Research Telescope System (SMARTS) Consortium and the Curtis-Schmidt 0.6 m Michigan Orbital Debris Space Debris Telescope both located at Cerro Tololo Inter-American Observatory (CTIO). An empirical based optical characterization model will be presented to provide preliminary correlations between laboratory based and telescope-based data in the context of classification of GEO debris objects.

Key Performance Indicators to Measure Improvement After Implementation of Total Laboratory Automation Abbott Accelerator a3600.

Science.gov (United States)

Miler, Marijana; Nikolac Gabaj, Nora; Dukic, Lora; Simundic, Ana-Maria

2017-12-27

The aim of the study was to estimate improvement of work efficiency in the laboratory after implementation of total laboratory automation (TLA) by Abbott Accelerator a3600 in the laboratory with measuring different key performance indicators (KPIs) before and after TLA implementation. The objective was also to recommend steps for defining KPIs in other laboratories. For evaluation of improvement 10 organizational and/or technical KPIs were defined for all phases of laboratory work and measured before (November 2013) and after (from 2015 to 2017) TLA implementation. Out of 10 defined KPIs, 9 were successfully measured and significantly improved. Waiting time for registration of samples in the LIS was significantly reduced from 16 (9-28) to 9 (6-16) minutes after TLA (P performed at core biochemistry analyzers which significantly reduced walking distance for sample management (for more than 800 m per worker) and number of tube touches (for almost 50%). Analyzers downtime and engagement time for analyzers maintenance was reduced for 50 h and 28 h per month, respectively. TLA eliminated manual dilution of samples with extreme results with sigma values increment from 3.4 to >6 after TLA. Although median turnaround time TAT for potassium and troponin was higher (for approximately 20 min), number of outliers with TAT >60 min expressed as sigma values were satisfying (>3). Implementation of the TLA improved the most of the processes in our laboratory with 9 out of 10 properly defined and measured KPIs. With proper planning and defining of KPIs, every laboratory could measure changes in daily workflow.

An international marine-atmospheric 222Rn measurement intercomparison in Bermuda. Part 2: Results for the participating laboratories

International Nuclear Information System (INIS)

Colle, R.; Unterweger, M.P.; Hutchinson, J.M.R.

1996-01-01

As part of an international measurement intercomparison of instruments used to measure atmospheric 222 Rn, four participating laboratories made nearly simultaneous measurements of 222 Rn activity concentration in commonly sampled, ambient air over approximately a 2 week period, and three of these four laboratories participated in the measurement comparison of 14 introduced samples with known, but undisclosed (blind) 222 Rn activity concentration. The exercise was conducted in Bermuda in October 1991. The 222 Rn activity concentrations in ambient Bermudian air over the course of the intercomparison ranged from a few hundredths of a Bq · m -3 to about 2 Bq · m -3 , while the standardized sample additions covered a range from approximately 2.5 Bq · m -3 to 35 Bq · m -3 . The overall uncertainty in the latter concentrations was in the general range of 10%, approximating a 3 standard deviation uncertainty interval. The results of the intercomparison indicated that two of the laboratories were within very good agreement with the standard additions, and almost within expected statistical variations. These same two laboratories, however, at lower ambient concentrations, exhibited a systematic difference with an averaged offset of roughly 0.3 Bq · m -3 . The third laboratory participating in the measurement of standardized sample additions was systematically low by about 65% to 70%, with respect to the standard addition which was also confirmed in their ambient air concentration measurements. The fourth laboratory, participating in only the ambient measurement part of the intercomparison, was also systematically low by at least 40% with respect to the first two laboratories

Mounted Smartphones as Measurement and Control Platforms for Motor-Based Laboratory Test-Beds

Directory of Open Access Journals (Sweden)

Jared A. Frank

2016-08-01

Full Text Available Laboratory education in science and engineering often entails the use of test-beds equipped with costly peripherals for sensing, acquisition, storage, processing, and control of physical behavior. However, costly peripherals are no longer necessary to obtain precise measurements and achieve stable feedback control of test-beds. With smartphones performing diverse sensing and processing tasks, this study examines the feasibility of mounting smartphones directly to test-beds to exploit their embedded hardware and software in the measurement and control of the test-beds. This approach is a first step towards replacing laboratory-grade peripherals with more compact and affordable smartphone-based platforms, whose interactive user interfaces can engender wider participation and engagement from learners. Demonstrative cases are presented in which the sensing, computation, control, and user interaction with three motor-based test-beds are handled by a mounted smartphone. Results of experiments and simulations are used to validate the feasibility of mounted smartphones as measurement and feedback control platforms for motor-based laboratory test-beds, report the measurement precision and closed-loop performance achieved with such platforms, and address challenges in the development of platforms to maintain system stability.

Mounted Smartphones as Measurement and Control Platforms for Motor-Based Laboratory Test-Beds.

Science.gov (United States)

Frank, Jared A; Brill, Anthony; Kapila, Vikram

2016-08-20

Laboratory education in science and engineering often entails the use of test-beds equipped with costly peripherals for sensing, acquisition, storage, processing, and control of physical behavior. However, costly peripherals are no longer necessary to obtain precise measurements and achieve stable feedback control of test-beds. With smartphones performing diverse sensing and processing tasks, this study examines the feasibility of mounting smartphones directly to test-beds to exploit their embedded hardware and software in the measurement and control of the test-beds. This approach is a first step towards replacing laboratory-grade peripherals with more compact and affordable smartphone-based platforms, whose interactive user interfaces can engender wider participation and engagement from learners. Demonstrative cases are presented in which the sensing, computation, control, and user interaction with three motor-based test-beds are handled by a mounted smartphone. Results of experiments and simulations are used to validate the feasibility of mounted smartphones as measurement and feedback control platforms for motor-based laboratory test-beds, report the measurement precision and closed-loop performance achieved with such platforms, and address challenges in the development of platforms to maintain system stability.

Collimation system for the VUV free-electron laser at the TESLA test facility

International Nuclear Information System (INIS)

Schlarb, H.

2001-11-01

To perform a proof-of-principle experiment for a Free Electron Laser operating at VUV wavelengths an undulator has been installed in the TESLA Test Facility linac phase I. To meet the requirements on the magnetic field quality in the undulator, a hybrid type structure with NdFeB permanent magnets has been chosen. The permanent magnets are sensitive to radiation by high energy particles. In order to perform the various experiments planned at the TESLA Test Facility linac, a collimator section has been installed to protect the undulator from radiation. In this thesis the design, performance and required steps for commissioning the collimator system are presented. To identify potential difficulties for the linac operation, the beam halo and the dark current transport through the entire linac is discussed. Losses of primary electrons caused by technical failures, component misalignments, and operation errors are investigated by tracking simulations, in order to derive a complete understanding of the absorbed dose in the permanent magnets of the undulator. Various topics related to a collimator system such as the removal of secondary particles produced at the collimators, generation and shielding of neutrons, excitation of wake fields, and beam based alignment concepts are important subjects of this thesis. (orig.)

High resolution VUV matrix isolation spectroscopy using synchrotron radiation: N2 in Ne

International Nuclear Information System (INIS)

Guertler, P.; Koch, E.E.

1980-01-01

We have investigated the VUV absorption spectrum of nitrogen in a neon matrix exploiting the intense synchrotron radiation continuum of the storage ring DORIS and the high resolving power of a 3 m normal incidence monochromator. With an improved sample preparation technique we were able to observe both the allowed transitions b 1 PIsub(u) and b 1 Σ + sub(u) between 12.4 and 14.0 eV and even the forbidden transitions w 1 Δsub(u) and a 1 PIsub(g) between 8.0 and 11.0 eV. All four transitions consist of long progressions of sharp bands (GAMMA approx. 10 meV) which are deperturbed in the matrix due to the suppression of nearby Rydberg states. Using symmetry arguments, our analysis of the spectra leads us to the conclusion that the N 2 molecule is oriented along the (1,1,1) direction in the host lattice. A detailed fine structure is observed for most bands of the first time. This fine structure is caused by dynamical interactions of the excited molecules with the matrix and is interpreted as excitation of librational modes of the N 2 molecule and a selective coupling to phonon modes of the neon lattice. (orig.)

The LUT-Gauge for overcoring rock stress measurements - Technical description and laboratory evaluation

International Nuclear Information System (INIS)

Leijon, B.

1988-03-01

The development of the LUT-Gauge - a triaxial borehole instrument for overcoring rock stress measurements - is reported. The borehole gauge and the associated equipment is described in some detail. The experimental procedures applicable to field measurements with the device are presented. A series of laboratory tests, aimed at investigating the performance of the instrumentation, are reported, This included basic tests of mechanical and electrical reliability, as well as investigations of the thermal sensitivity of the measuring method. These factors are significant with respect to the applicability of the method under field conditions. The results from the laboratory tests showed that instrument performance was in all respects satisfactory. Furthermore, that the effects of temperature changes, expressed as the corresponding measuring error to be expected under typical field conditions, was less than ± 1 MPa. (author)

Porosity measurements of crystalline rocks by laboratory and geophysical methods

International Nuclear Information System (INIS)

Alexander, J.; Hall, D.H.; Storey, B.C.

1981-12-01

Porosity values of igneous and metamorphic crystalline rocks have been determined from core samples taken at specific depths from Altnabreac, by a combination of laboratory and geophysical techniques. Using resaturation and mercury injection methods in three laboratories within I.G.S., porosity values have been derived and the effect of variations in the measuring techniques and results obtained have been compared. Comparison of inter-laboratory porosity values illustrates that systematic errors are present, resulting in higher porosity values for samples subjected to re-testing. This is considered to be caused by the variable nature of the initial samples combined with the inability to completely dry or resaturate samples during a second testing. Geophysical techniques for determining in situ porosity using the neutron log have been carried out in borehole ALA. The neutron log has been calibrated with laboratory derived porosity values and an empirical formula derived enabling porosity values to be ascribed throughout the logged borehole ALA. Comparison of the porosity results from Altnabreac with crystalline samples elsewhere in America, Europe and the U.K. suggest that porosities at Altnabreac are lower than average. However, very few publications concerned with water movement in crystalline areas actually state the method used. (author)

Effect of the methyl substitution on the combustion of two methylheptane isomers: Flame chemistry using vacuum-ultraviolet (VUV) photoionization mass spectrometry

KAUST Repository

Selim, Hatem

2015-04-16

Alkanes with one or more methyl substitutions are commonly found in liquid transportation fuels, so a fundamental investigation of their combustion chemistry is warranted. In the present work, stoichiometric low-pressure (20 Torr) burner-stabilized flat flames of 2-methylheptane and 3-methylheptane were investigated. Flame species were measured via time-of-flight molecular-beam mass spectrometry, with vacuum-ultraviolet (VUV) synchrotron radiation as the ionization source. Mole fractions of major end-products and intermediate species (e.g., alkanes, alkenes, alkynes, aldehydes, and dienes) were quantified axially above the burner surface. Mole fractions of several free radicals were also measured (e.g., CH3, HCO, C2H3, C3H3, and C3H5). Isomers of different species were identified within the reaction pool by an energy scan between 8 and 12 eV at a distance of 2.5 mm away from the burner surface. The role of methyl substitution location on the alkane chain was determined via comparisons of similar species trends obtained from both flames. The results revealed that the change in CH3 position imposed major differences on the combustion of both fuels. Comparison with numerical simulations was performed for kinetic model testing. The results provide a comprehensive set of data about the combustion of both flames, which can enhance the erudition of both fuels combustion chemistry and also improve their chemical kinetic reaction mechanisms. © 2015 American Chemical Society.

The procedures manual of the Environmental Measurements Laboratory. Volume 1, 28. edition

Energy Technology Data Exchange (ETDEWEB)

Chieco, N.A. [ed.

1997-02-01

This manual covers procedures and technology currently in use at the Environmental Measurements Laboratory. An attempt is made to be sure that all work carried out will be of the highest quality. Attention is focused on the following areas: quality assurance; sampling; radiation measurements; analytical chemistry; radionuclide data; special facilities; and specifications.

The procedures manual of the Environmental Measurements Laboratory. Volume 1, 28. edition

International Nuclear Information System (INIS)

Chieco, N.A.

1997-02-01

This manual covers procedures and technology currently in use at the Environmental Measurements Laboratory. An attempt is made to be sure that all work carried out will be of the highest quality. Attention is focused on the following areas: quality assurance; sampling; radiation measurements; analytical chemistry; radionuclide data; special facilities; and specifications

Measurement comparisons of radioactivity among European monitoring laboratories for the environment and food stuff

International Nuclear Information System (INIS)

Waetjen, U.; Spasova, Y.; Altzitzoglou, T.

2008-01-01

For more than 15 years, European Union (EU) laboratories monitoring environmental radioactivity have been obliged to participate in measurement comparisons organised by the European Commission. After a short review of comparisons conducted during the 1990s, the approach of IRMM organising these comparisons since 2003 is presented. It relies on the provision of comparison samples with reference values traceable to the International Reference System for radionuclides (SIR). The results of the most recent comparison, the determination of 40 K, 90 Sr and 137 Cs in milk powder, are presented. The influence of repetitive participation in measurement comparisons on laboratory performance is studied on the basis of data from more than 20 laboratories having participated in several exercises during the last 15 years

Effects of vacuum-ultraviolet irradiation on copper penetration into low-k dielectrics under bias-temperature stress

Energy Technology Data Exchange (ETDEWEB)

Guo, X.; Zheng, H.; Xue, P.; Shohet, J. L. [Plasma Processing and Technology Laboratory and Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); King, S. W. [Logic Technology Development, Intel Corporation, Hillsboro, Oregon 97124 (United States); Nishi, Y. [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States)

2015-01-05

The effects of vacuum-ultraviolet (VUV) irradiation on copper penetration into non-porous low-k dielectrics under bias-temperature stress (BTS) were investigated. By employing x-ray photoelectron spectroscopy depth-profile measurements on both as-deposited and VUV-irradiated SiCOH/Cu stacks, it was found that under the same BTS conditions, the diffusion depth of Cu into the VUV-irradiated SiCOH is higher than that of as-deposited SiCOH. On the other hand, under the same temperature-annealing stress (TS) without electric bias, the Cu distribution profiles in the VUV-irradiated SiCOH were same with that for the as-deposited SiCOH. The experiments suggest that in as-deposited SiCOH, the diffused Cu exists primarily in the atomic state, while in VUV-irradiated SiCOH, the diffused Cu is oxidized by the hydroxyl ions (OH{sup −}) generated from VUV irradiation and exists in the ionic state. The mechanisms for metal diffusion and ion injection in VUV irradiated low-k dielectrics are discussed.

Design and implementation of a virtual laboratory of radiation measurement

International Nuclear Information System (INIS)

Alvarez T, J. R.; Morales S, J. B.

2009-10-01

The work involves the implementation of a virtual laboratory, this project is conducted in the Faculty of Engineering of National Autonomous University of Mexico with the name of LANUVI. It is intended that the laboratory can be used by students who have interest in the nuclear radiation knowledge as well as in its detection and attenuation, in addition serve as and introduction to nuclear systems. In the first part of project will conduct a source that can simulate the particle radiation of Alfa, beta, neutrons and gamma rays. The project will take sources used in class laboratories and elements that are dangerous but are used in different practical applications. After taking the source analyzing the particles behaviour in different media like air, animal tissue, aluminium, lead, etc. The analysis is done in different ways in order to know with which material can stop or mitigate the different types of radiation. Finally shall be measure radioactivity with different types of detectors. At this point, has the behaviour of ionization chamber but in the future is expected to make the simulation of some other radiation detectors. The mathematical models we represent the behaviour of these cases were implemented in free software. The program will be used to implement the virtual laboratory with radiation sources, detectors and different types of shields will be Blender which is a free software that is used by many users for the embodiment of games but try to use as a tool to help visualize the different equipment that is widely used in a radioactive materials laboratory. (Author)

The Stanford Synchrotron Radiation Laboratory, 20 years of synchrotron light

International Nuclear Information System (INIS)

Cantwell, K.

1993-08-01

The Stanford Synchrotron Radiation Laboratory (SSRL) is now operating as a fully dedicated light source with low emittance electron optics, delivering high brightness photon beams to 25 experimental stations six to seven months per year. On October 1, 1993 SSRL became a Division of the Stanford Linear Accelerator Center, rather than an Independent Laboratory of Stanford University, so that high energy physics and synchrotron radiation now function under a single DOE contract. The SSRL division of SLAC has responsibility for operating, maintaining and improving the SPEAR accelerator complex, which includes the storage ring and a 3 GeV injector. SSRL has thirteen x-ray stations and twelve VUV/Soft x-ray stations serving its 600 users. Recently opened to users is a new spherical grating monochromator (SGM) and a multiundulator beam line. Circularly polarized capabilities are being exploited on a second SGM line. New YB 66 crystals installed in a vacuum double-crystal monochromator line have sparked new interest for Al and Mg edge studies. One of the most heavily subscribed stations is the rotation camera, which has been recently enhanced with a MAR imaging plate detector system for protein crystallography on a multipole wiggler. Under construction is a new wiggler-based structural molecular biology beam line with experimental stations for crystallography, small angle scattering and x-ray absorption spectroscopy. Plans for new developments include wiggler beam lines and associated facilities specialized for environmental research and materials processing

Laboratory microwave measurement of the moisture content in seed cotton and ginned cotton fiber

Science.gov (United States)

The timely and accurate measurement of cotton fiber moisture content is important, but the measurement is often performed by laborious, time-consuming laboratory oven drying methods. Microwave technology for measuring fiber moisture content directly (not for drying only) offers potential advantages...

Methods of Estimation the Reliability and Increasing the Informativeness of the Laboratory Results (Analysis of the Laboratory Case of Measurement the Indicators of Thyroid Function)

OpenAIRE

N A Kovyazina; N A Alhutova; N N Zybina; N M Kalinina

2014-01-01

The goal of the study was to demonstrate the multilevel laboratory quality management system and point at the methods of estimating the reliability and increasing the amount of information content of the laboratory results (on the example of the laboratory case). Results. The article examines the stages of laboratory quality management which has helped to estimate the reliability of the results of determining Free T3, Free T4 and TSH. The measurement results are presented by the expanded unce...

A FMEA clinical laboratory case study: how to make problems and improvements measurable.

Science.gov (United States)

Capunzo, Mario; Cavallo, Pierpaolo; Boccia, Giovanni; Brunetti, Luigi; Pizzuti, Sante

2004-01-01

The authors have experimented the application of the Failure Mode and Effect Analysis (FMEA) technique in a clinical laboratory. FMEA technique allows: a) to evaluate and measure the hazards of a process malfunction, b) to decide where to execute improvement actions, and c) to measure the outcome of those actions. A small sample of analytes has been studied: there have been determined the causes of the possible malfunctions of the analytical process, calculating the risk probability index (RPI), with a value between 1 and 1,000. Only for the cases of RPI > 400, improvement actions have been implemented that allowed a reduction of RPI values between 25% to 70% with a costs increment of FMEA technique can be applied to the processes of a clinical laboratory, even if of small dimensions, and offers a high potential of improvement. Nevertheless, such activity needs a thorough planning because it is complex, even if the laboratory already operates an ISO 9000 Quality Management System.

Methodologically controlled variations in laboratory and field pH measurements in waterlogged soils

DEFF Research Database (Denmark)

Elberling, Bo; Matthiesen, Henning

2007-01-01

artefacts is critical. But the study includes agricultural and forest soils for comparison. At a waterlogged site, Laboratory results were compared with three different field methods: calomel pH probes inserted in the soil from pits, pH measurements of soil solution extracted from the soil, and pH profiles...... using a solid-state pH electrode pushed into the soil from the surface. Comparisons between in situ and laboratory methods revealed differences of more than 1 pH unit. The content of dissolved ions in soil solution and field observations of O2 and CO2 concentrations were used in the speciation model...... PHREEQE in order to predict gas exchange processes. Changes in pH in soil solution following equilibrium in the laboratory could be explained mainly by CO2 degassing. Only soil pH measured in situ using either calomel or solid-state probes inserted directly into the soil was not affected by gas exchange...

Methods of the physics of porous media

CERN Document Server

Wong, Po-Zen; De Graef, Marc

1999-01-01

Over the past 25 years, the field of VUV physics has undergone significant developments as new powerful spectroscopic tools, VUV lasers, and optical components have become available. This volume is aimed at experimentalists who are in need of choosing the best type of modern instrumentation in this applied field. In particular, it contains a detailed chapter on laboratory sources. This volume provides an up-to-date description of state-of-the-art equipment and techniques, and a broad reference bibliography. It treats phenomena from the standpoint of an experimental physicist, whereby such topi

Sequim Marine Research Laboratory routine environmental measurements during CY-1978

International Nuclear Information System (INIS)

Houston, J.R.; Blumer, P.J.

1979-03-01

Environmental data collected during 1978 in the vicinity of the Marine Research Laboratory show continued compliance with all applicable state and federal regulations and furthermore show no detectable change from conditions that existed in previous years. Samples collected for radiological analysis included soil, drinking water, bay water, clams, and seaweed. Radiation dose rates at 1 meter aboveground were also measured

Mounted Smartphones as Measurement and Control Platforms for Motor-Based Laboratory Test-Beds †

Science.gov (United States)

Frank, Jared A.; Brill, Anthony; Kapila, Vikram

2016-01-01

Laboratory education in science and engineering often entails the use of test-beds equipped with costly peripherals for sensing, acquisition, storage, processing, and control of physical behavior. However, costly peripherals are no longer necessary to obtain precise measurements and achieve stable feedback control of test-beds. With smartphones performing diverse sensing and processing tasks, this study examines the feasibility of mounting smartphones directly to test-beds to exploit their embedded hardware and software in the measurement and control of the test-beds. This approach is a first step towards replacing laboratory-grade peripherals with more compact and affordable smartphone-based platforms, whose interactive user interfaces can engender wider participation and engagement from learners. Demonstrative cases are presented in which the sensing, computation, control, and user interaction with three motor-based test-beds are handled by a mounted smartphone. Results of experiments and simulations are used to validate the feasibility of mounted smartphones as measurement and feedback control platforms for motor-based laboratory test-beds, report the measurement precision and closed-loop performance achieved with such platforms, and address challenges in the development of platforms to maintain system stability. PMID:27556464

Clinical evaluation of analytical variations in serum creatinine measurements : why laboratories should abandon Jaffe techniques

NARCIS (Netherlands)

Drion, Iefke; Cobbaert, Christa; Groenier, Klaas H.; Weykamp, Cas; Bilo, Henk J. G.; Wetzels, Jack F. M.; Kleefstra, Nanne

2012-01-01

Background: Non-equivalence in serum creatinine (SCr) measurements across Dutch laboratories and the consequences hereof on chronic kidney disease (CKD) staging were examined. Methods: National data from the Dutch annual external quality organization of 2009 were used. 144 participating laboratories

LABORATORY EVALUATION OF AIR FLOW MEASUREMENT METHODS FOR RESIDENTIAL HVAC RETURNS

Energy Technology Data Exchange (ETDEWEB)

Walker, Iain; Stratton, Chris

2015-02-01

This project improved the accuracy of air flow measurements used in commissioning California heating and air conditioning systems in Title 24 (Building and Appliance Efficiency Standards), thereby improving system performance and efficiency of California residences. The research team at Lawrence Berkeley National Laboratory addressed the issue that typical tools used by contractors in the field to test air flows may not be accurate enough to measure return flows used in Title 24 applications. The team developed guidance on performance of current diagnostics as well as a draft test method for use in future evaluations. The series of tests performed measured air flow using a range of techniques and devices. The measured air flows were compared to reference air flow measurements using inline air flow meters built into the test apparatus. The experimental results showed that some devices had reasonable results (typical errors of 5 percent or less) but others had much bigger errors (up to 25 percent). Because manufacturers’ accuracy estimates for their equipment do not include many of the sources of error found in actual field measurements (and replicated in the laboratory testing in this study) it is essential for a test method that could be used to determine the actual uncertainty in this specific application. The study team prepared a draft test method through ASTM International to determine the uncertainty of air flow measurements at residential heating ventilation and air conditioning returns and other terminals. This test method, when finalized, can be used by the Energy Commission and other entities to specify required accuracy of measurement devices used to show compliance with standards.

Implementing and measuring the level of laboratory service integration in a program setting in Nigeria.

Science.gov (United States)

Mbah, Henry; Negedu-Momoh, Olubunmi Ruth; Adedokun, Oluwasanmi; Ikani, Patrick Anibbe; Balogun, Oluseyi; Sanwo, Olusola; Ochei, Kingsley; Ekanem, Maurice; Torpey, Kwasi

2014-01-01

The surge of donor funds to fight HIV&AIDS epidemic inadvertently resulted in the setup of laboratories as parallel structures to rapidly respond to the identified need. However these parallel structures are a threat to the existing fragile laboratory systems. Laboratory service integration is critical to remedy this situation. This paper describes an approach to quantitatively measure and track integration of HIV-related laboratory services into the mainstream laboratory services and highlight some key intervention steps taken, to enhance service integration. A quantitative before-and-after study conducted in 122 Family Health International (FHI360) supported health facilities across Nigeria. A minimum service package was identified including management structure; trainings; equipment utilization and maintenance; information, commodity and quality management for laboratory integration. A check list was used to assess facilities at baseline and 3 months follow-up. Level of integration was assessed on an ordinal scale (0 = no integration, 1 = partial integration, 2 = full integration) for each service package. A composite score grading expressed as a percentage of total obtainable score of 14 was defined and used to classify facilities (≤ 80% FULL, 25% to 79% PARTIAL and laboratory systems were 64 (52.5%) and 0 (0.0%) at baseline, compared to 100 (82.0%) and 3 (2.4%) respectively at 3 months follow-up (p = 0.000). This project showcases our novel approach to measure the status of each laboratory on the integration continuum.

Report on interlaboratory comparisons of 14C measurements organized by the environmental research branch, Chalk River Laboratories

International Nuclear Information System (INIS)

Milton, G.M.; Kramer, S.J.; Cooper, E.L.; Rao, R.R.; Milton, J.C.D.

1996-02-01

The need for increased quality assurance for measurements performed by the monitoring laboratories at nuclear stations has spurred the introduction of a number of laboratory intercomparisons. This report provides details of two intercomparisons of 14 C measurements, including the preparation of potential secondary reference materials, the range of analytical techniques in use at the participating laboratories, and a statistical analysis of the results reported. The agreement evident in the two sets of materials - milk and vegetation - was good. (author)

Framework for laboratory harmonization of folate measurements in low- and middle-income countries and regions.

Science.gov (United States)

Pfeiffer, Christine M; Zhang, Mindy; Jabbar, Shameem

2018-02-01

The measurement of serum and red blood cell folate, two commonly used biomarkers of folate status in populations, is complicated by analytical and data interpretation challenges. Folate results show poor comparability across laboratories, even using the same analytical technique. The folate microbiologic assay produces accurate results and requires simple instrumentation. Thus, it could be set up and maintained in low- and middle-income country laboratories. However, the assay has to be harmonized through the use of common critical reagents (e.g., microorganism and folate calibrator) in order to produce comparable results across laboratories and over time, so that the same cutoff values can be applied across surveys. There is a limited need for blood folate measurements in a country owing to the periodic nature of surveys. Having a network of regional resource laboratories proficient in conducting the folate microbiologic assay and willing and able to perform service work for other countries will be the most efficient way to create an infrastructure wherein qualified laboratories produce reliable blood folate data. Continuous participation of these laboratories in a certification program can verify and document their proficiency. If the resource laboratories conduct the work on a fee-for-service basis, they could become self-sustaining in the long run. © 2018 This article is a U.S. Government work and is in the public domain in the USA.

Routine internal- and external-quality control data in clinical laboratories for estimating measurement and diagnostic uncertainty using GUM principles.

Science.gov (United States)

Magnusson, Bertil; Ossowicki, Haakan; Rienitz, Olaf; Theodorsson, Elvar

2012-05-01

Healthcare laboratories are increasingly joining into larger laboratory organizations encompassing several physical laboratories. This caters for important new opportunities for re-defining the concept of a 'laboratory' to encompass all laboratories and measurement methods measuring the same measurand for a population of patients. In order to make measurement results, comparable bias should be minimized or eliminated and measurement uncertainty properly evaluated for all methods used for a particular patient population. The measurement as well as diagnostic uncertainty can be evaluated from internal and external quality control results using GUM principles. In this paper the uncertainty evaluations are described in detail using only two main components, within-laboratory reproducibility and uncertainty of the bias component according to a Nordtest guideline. The evaluation is exemplified for the determination of creatinine in serum for a conglomerate of laboratories both expressed in absolute units (μmol/L) and relative (%). An expanded measurement uncertainty of 12 μmol/L associated with concentrations of creatinine below 120 μmol/L and of 10% associated with concentrations above 120 μmol/L was estimated. The diagnostic uncertainty encompasses both measurement uncertainty and biological variation, and can be estimated for a single value and for a difference. This diagnostic uncertainty for the difference for two samples from the same patient was determined to be 14 μmol/L associated with concentrations of creatinine below 100 μmol/L and 14 % associated with concentrations above 100 μmol/L.

Characterization of Orbital Debris Photometric Properties Derived from Laboratory-Based Measurements

Science.gov (United States)

Cowardin, Heather; Seitzer, Pat; Abercromby, Kira; Barker, Ed; Schildknecht, Thomas

2010-01-01

Capitalizing on optical data products and applying them to generate a more complete understanding of orbital space objects, is a key objective of NASA's Optical Measurement Program, and a primary objective for the creation of the Optical Measurements Center(OMC). The OMC attempts to emulate space-based illumination conditions using equipment and techniques that parallel telescopic observations and source-target-sensor orientations. The data acquired in the OMC are a function of known shape, size, and material. These three physical parameters are key to understanding the orbital debris environment in more depth. For optical observations, one must rely on spectroscopic or photometric measurements to ascertain an object's material type. Determination of an object s shape using remote observations is more complicated due to the various light scattering properties each object present and is a subject that requires more study. It is much easier to look at the periodicity of the light curve and analyze its structure for rotation. In order to best simulate the orbital debris population, three main sources were used as test fragments for optical measurements: flight-ready materials, destructive hypervelocity testing (simulating on-orbit collisions) and destructive pressure testing (simulating on-orbit explosions). Laboratory optical characteristics of fragments were measured, including light curve shape, phase angle dependence, and photometric and spectroscopic color indices. These characteristics were then compared with similar optical measurements acquired from telescopic observations in order to correlate remote and laboratory properties with the intent of ascertaining the intrinsic properties of the observed orbital debris

Laboratory Measurements for H3+ Deuteration Reactions

Science.gov (United States)

Bowen, Kyle; Hillenbrand, Pierre-Michel; Urbain, Xavier; Savin, Daniel Wolf

2018-06-01

Deuterated molecules are important chemical tracers of protostellar cores. At the ~106 cm-3 particle densities and ~20 K temperatures typical for protostellar cores, most molecules freeze onto dust grains. A notable exception is H3+ and its isotopologues. These become important carriers of positive charge in the gas, can couple to any ambient magnetic field, and can thereby alter the cloud dynamics. Knowing the total abundance of H3+ and its isotopologues is important for studying the evolution of protostellar cores. However, H3+ and D3+ have no dipole moment. They lack a pure rotational spectrum and are not observable at protostellar core temperatures. Fortunately H2D+ and D2H+ have dipole moments and a pure rotational spectrum that can be excited in protostellar cores. Observations of these two molecules, combined with astrochemical models, provide information about the total abundance of H3+ and all its isotopologues. The inferred abundances, though, rely on accurate astrochemical data for the deuteration of H3+ and its isotopologues.Here we present laboratory measurements of the rate coefficients for three important deuterating reactions, namely D + H3+/H2D+/D2H+ → H + H2D+/ D2H+/D3+. Astrochemical models currently rely on rate coefficients from classical (Langevin) or semi-classical methods for these reactions, as fully quantum-mechanical calculations are beyond current computational capabilities. Laboratory studies are the most tractable means of providing the needed data. For our studies we used our novel dual-source, merged fast-beams apparatus, which enables us to study reactions of neutral atoms and molecular ions. Co-propagating beams allow us to measure experimental rate coefficients as a function of collision energy. We extract cross section data from these results, which we then convolve with a Maxwell-Boltzmann distribution to generate thermal rate coefficients. Here we present our results for these three reactions and discuss some implications.

Comparison of CO/sub 2/ measurements by two laboratories on air from bubbles in polar ice

Energy Technology Data Exchange (ETDEWEB)

Barnola, J.M.; Raynaud, D.; Neftel, A.; Oeschger, H.

1983-06-02

The CO/sub 2/ content of air enclosed in bubbles in polar ice has been reported by two laboratories (in Grenoble and Bern) to be representative of the atmospheric CO/sub 2/ concentration at the time the ice was formed. Such ice core studies indicate lower concentrations in ice formed at the end of the ice age, around 18,000 yr BP, and several explanations have been proposed for such a change. Both laboratories are currently measuring various ice cores in order to determine the pre-AD 1850 CO/sub 2/ level in the atmosphere, which relates to the partitioning of anthropogenic CO/sub 2/ among the atmospheric, biospheric and oceanic reservoirs. The two laboratories use different ice cores and different analytical procedures and, therefore, there is a need to know to what extent the measurements are quantitatively comparable. The results are presented of a comparison between the two laboratories based on measurements from the same ice core sections, which indicate that the measurements can be compared with great confidence. The results suggest that the mean CO/sub 2/ level recorded by Antartic ice for the period 800-2500 yr BP is about 260 p.p.m.v.

Environmental gamma background measurements in China Jinping Underground Laboratory

International Nuclear Information System (INIS)

Zhi Zeng; Jian Su; Hao Ma; Hengguan Yi; Jianping Cheng; Qian Yue; Junli Li; Hui Zhang

2014-01-01

To determine the environmental gamma background levels which affects rare events experiments, we measured in situ gamma spectrum at four locations in the China Jinping Underground Laboratory. The integral background count rates (40-2,700 keV) varied from 3.76 to 74.1 cps. The average count rate of the measurements inside the CJPL was 73.4 cps. The spectrometer was calibrated with a 152 Eu point source and Monte Carlo simulation to obtain the activity conversion factors for the rock and the air, respectively. The rocks that surrounded the CJPL was characterized by very low activity concentrations of 238 U (3.69-4.21 Bq kg -1 ), 232 Th (0.52-0.64 Bq kg -1 ) and 40 K (4.28 Bq kg -1 ). (author)

Dissociative photoionization of the NO molecule studied by photoelectron-photon coincidence technique

International Nuclear Information System (INIS)

Kivimaeki, A.; Alvarez-Ruiz, J.; Coreno, M.; Simone, M. de; Moise, A.; Partanen, L.; Richter, R.; Stankiewicz, M.

2010-01-01

Low-energy photoelectron-vacuum ultraviolet (VUV) photon coincidences have been measured using synchrotron radiation excitation in the inner-valence region of the nitric oxide molecule. The capabilities of the coincidence set-up were demonstrated by detecting the 2s -1 → 2p -1 radiative transitions in coincidence with the 2s photoelectron emission in Ne. In NO, the observed coincidence events are attributed to dissociative photoionization with excitation, whereby photoelectron emission is followed by fragmentation of excited NO + ions into O + + N* or N + + O* and VUV emission from an excited neutral fragment. The highest coincidence rate occurs with the opening of ionization channels which are due to correlation satellites of the 3σ photoionization. The decay time of VUV photon emission was also measured, implying that specific excited states of N atoms contribute significantly to observed VUV emission.

Effectiveness of a GUM-compliant course for teaching measurement in the introductory physics laboratory

International Nuclear Information System (INIS)

Pillay, Seshini; Buffler, Andy; Lubben, Fred; Allie, Saalih

2008-01-01

An evaluation of a course aimed at developing university students' understanding of the nature of scientific measurement and uncertainty is described. The course materials follow the framework for metrology as recommended in the Guide to the Expression of Uncertainty in Measurement (GUM). The evaluation of the course is based on responses to written questionnaires administered to a cohort of 76 first year physics students both pre- and post-instruction, which were interpreted in terms of 'point' or 'set' reasoning. These findings are compared with responses from a control group of 70 students who completed a similar laboratory course apart from the use of traditional approaches to measurement and data analysis. The results suggest that the GUM framework, together with the specific teaching strategies described, provides opportunities for more effective learning of measurement and uncertainty in the introductory laboratory

The bogus taste test: Validity as a measure of laboratory food intake

OpenAIRE

Robinson, Eric; Haynes, Ashleigh; Hardman, Charlotte A.; Kemps, Eva; Higgs, Suzanne; Jones, Andrew

2017-01-01

Because overconsumption of food contributes to ill health, understanding what affects how much people eat is of importance. The ?bogus? taste test is a measure widely used in eating behaviour research to identify factors that may have a causal effect on food intake. However, there has been no examination of the validity of the bogus taste test as a measure of food intake. We conducted a participant level analysis of 31 published laboratory studies that used the taste test to measure food inta...

Understanding water uptake in bioaerosols using laboratory measurements, field tests, and modeling

Science.gov (United States)

Chaudhry, Zahra; Ratnesar-Shumate, Shanna A.; Buckley, Thomas J.; Kalter, Jeffrey M.; Gilberry, Jerome U.; Eshbaugh, Jonathan P.; Corson, Elizabeth C.; Santarpia, Joshua L.; Carter, Christopher C.

2013-05-01

Uptake of water by biological aerosols can impact their physical and chemical characteristics. The water content in a bioaerosol can affect the backscatter cross-section as measured by LIDAR systems. Better understanding of the water content in controlled-release clouds of bioaerosols can aid in the development of improved standoff detection systems. This study includes three methods to improve understanding of how bioaerosols take up water. The laboratory method measures hygroscopic growth of biological material after it is aerosolized and dried. Hygroscopicity curves are created as the humidity is increased in small increments to observe the deliquescence point, then the humidity is decreased to observe the efflorescence point. The field component of the study measures particle size distributions of biological material disseminated into a large humidified chamber. Measurements are made with a Twin-Aerodynamic Particle Sizer (APS, TSI, Inc), -Relative Humidity apparatus where two APS units measure the same aerosol cloud side-by-side. The first operated under dry conditions by sampling downstream of desiccant dryers, the second operated under ambient conditions. Relative humidity was measured within the sampling systems to determine the difference in the aerosol water content between the two sampling trains. The water content of the bioaerosols was calculated from the twin APS units following Khlystov et al. 2005 [1]. Biological material is measured dried and wet and compared to laboratory curves of the same material. Lastly, theoretical curves are constructed from literature values for components of the bioaerosol material.

Incorporating spectroscopy and measurement technology into the high school chemistry laboratory

Science.gov (United States)

Harbert, Emily Ann

Science and technology are becoming increasingly important in maintaining a healthy economy at home and a competitive edge on the world stage, though that is just one facet affected by inadequate science education in the United States. Engaging students in the pursuit of knowledge and giving them the skills to think critically are paramount. One small way to assist in achieving these goals is to increase the quality and variety of technology-rich activities conducted in high school classrooms. Incorporating more laboratory measurement technology into high schools may incite more student interest in the processes and practices of science and may allow students to learn to think more critically about their data and what it represents. The first objective of the work described herein was to determine what measurement technology is being used in schools and to what extent, as well as to determine other teacher needs and preferences. Second, the objective was to develop a new program to provide incoming freshmen (or rising seniors) with measurement technology training they did not receive in high school, and expose them to new research and career opportunities in science. The final objective was to create a technology-rich classroom laboratory activity for use in high schools.

2D X-ray scanner and its uses in laboratory reservoir characterization measurements

Energy Technology Data Exchange (ETDEWEB)

Maloney, D.; Doggett, K.

1997-08-01

X-ray techniques are used in petroleum laboratories for a variety of reservoir characterization measurements. This paper describes the configuration of a 2D X-ray scanner and many of the ways in which it simplifies and improves accuracy`s of laboratory measurements. Linear X-ray scanners are most often used to provide descriptions of fluid saturations within core plugs during flow tests. We configured our linear scanner for both horizontal and vertical movement. Samples can be scanned horizontally, vertically, or according to horizontal and vertical grids. X-ray measurements are fast, allowing measurements of two- and three-phase fluid saturations during both steady- and unsteady-state flow processes. Rock samples can be scanned while they are subjected to stress, pore pressure, and temperature conditions simulating those of a petroleum reservoir. Many types of measurements are possible by selecting appropriate X-ray power settings, dopes, filters, and collimator configurations. The scanner has been used for a variety of applications besides fluid saturation measurements. It is useful for measuring porosity distributions in rocks, concentrations of X-ray dopes within flow streams during tracer tests, gap widths in fracture flow cells, fluid interface levels in PVT cells and fluid separators, and other features and phenomena.

Standard guide for qualification of measurement methods by a laboratory within the nuclear industry

CERN Document Server

American Society for Testing and Materials. Philadelphia

2003-01-01

1.1 This guide provides guidance for selecting, validating, and qualifying measurement methods when qualification is required for a specific program. The recommended practices presented in this guide provide a major part of a quality assurance program for the laboratory data (see Fig. 1). Qualification helps to assure that the data produced will meet established requirements. 1.2 The activities intended to assure the quality of analytical laboratory measurement data are diagrammed in Fig. 1. Discussion and guidance related to some of these activities appear in the following sections: Section Selection of Measurement Methods 5 Validation of Measurement Methods 6 Qualification of Measurement Methods 7 Control 8 Personnel Qualification 9 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitati...

LABORATORY MEASUREMENTS OF WHITE DWARF PHOTOSPHERIC SPECTRAL LINES: Hβ

International Nuclear Information System (INIS)

Falcon, Ross E.; Gomez, T. A.; Montgomery, M. H.; Winget, D. E.; Rochau, G. A.; Bailey, J. E.; Nagayama, T.

2015-01-01

We spectroscopically measure multiple hydrogen Balmer line profiles from laboratory plasmas to investigate the theoretical line profiles used in white dwarf (WD) atmosphere models. X-ray radiation produced at the Z Pulsed Power Facility at Sandia National Laboratories initiates plasma formation in a hydrogen-filled gas cell, replicating WD photospheric conditions. Here we present time-resolved measurements of Hβ and fit this line using different theoretical line profiles to diagnose electron density, n e , and n = 2 level population, n 2 . Aided by synthetic tests, we characterize the validity of our diagnostic method for this experimental platform. During a single experiment, we infer a continuous range of electron densities increasing from n e ∼ 4 to ∼30 × 10 16 cm −3 throughout a 120-ns evolution of our plasma. Also, we observe n 2 to be initially elevated with respect to local thermodynamic equilibrium (LTE); it then equilibrates within ∼55 ns to become consistent with LTE. This supports our electron-temperature determination of T e ∼ 1.3 eV (∼15,000 K) after this time. At n e ≳ 10 17 cm −3 , we find that computer-simulation-based line-profile calculations provide better fits (lower reduced χ 2 ) than the line profiles currently used in the WD astronomy community. The inferred conditions, however, are in good quantitative agreement. This work establishes an experimental foundation for the future investigation of relative shapes and strengths between different hydrogen Balmer lines

Quality control for radionuclide determinations in the Saxon state laboratories for environmental radioactivity by intercomparison and comparative measurements

International Nuclear Information System (INIS)

Knobus, B.

2001-01-01

Quality control for radionuclide analysis is necessary and essential for the quality assurance of the measuring results executing the measuring programmes of surveillance of the radioactivity in the environment and from installations. Acts, ordinances and guidelines require the participation in intercomparisons for authorized institutions detecting the demanded quality of measurements (e.g. trueness, reproducibility) for Federal Authorities. These are mainly those intercomparisons which are prepared, practised and evaluated by the federal laboratories. Comparative measurements are generally organized and executed by the state laboratory itself with a few participants for special measuring tasks. In this paper are described and discussed extend and special results of those intercomparisons and comparative measurements of the Saxon state laboratories for environmental radioactivity from 1992 until 2000. If necessary, there are following improvements for quality assurance. (orig.) [de

Gaerttner LINAC Laboratory report on international nuclear data measurements

International Nuclear Information System (INIS)

Mesh, D.W.; Block, R.C.

1999-04-01

The Gaerttner LINAC Laboratory has made neutron transmission and capture measurements up to several hundred eV on samples of Zr, Nb, Mo, Sm, Nd, Ho, Er, Tm, Hf, and W. A new neutron time-of-flight target has been built and installed and a new 6 Li glass transmission detector is under construction. The electron linear accelerator is being refurbished with new klystrons, a new RF transport system and the reinstallation of the ninth accelerating section. These improvements are intended to provide a more powerful and monoenergetic electron beam

Environmental Measurements Laboratory 1994 annual report

Energy Technology Data Exchange (ETDEWEB)

Chieco, N.A. [ed.; Krey, P.W.; Beck, H.L.

1995-08-01

This report summarizes the activities of the Environmental Measurements Laboratory (EML) for the calendar year 1994 and it serves as an annual report to the Director of the Office of Energy Research (ER), the Associate Director and staff of the Office of Health and Environmental Research (OHER), the manager and staff of the Chicago Field Office, and the authors colleagues. Emphasized are the progress and accomplishments of the year, rather than future plans or expectations. The technical summaries are grouped according to the following seven general program areas: environmental radiation and radioactivity; radiation transport and dosimetry; environmental radon, thoron, and related aerosols; atmospheric and surface pollutant studies related to global climate change; atmospheric chemistry; metrology, consultation, and emergency response; environmental management. EML`s mission is to address important scientific questions concerning human health and environmental impacts. Through its multidisciplinary staff, EML conducts experimental and theoretical research on radioactive and other energy-related pollutants, and provides DOE and other federal agencies with the in-house capability to respond effectively and efficiently with regard to quality assurance activities, environmental issues and related national security issues.

Environmental Measurements Laboratory 1994 annual report

International Nuclear Information System (INIS)

Chieco, N.A.; Krey, P.W.; Beck, H.L.

1995-08-01

This report summarizes the activities of the Environmental Measurements Laboratory (EML) for the calendar year 1994 and it serves as an annual report to the Director of the Office of Energy Research (ER), the Associate Director and staff of the Office of Health and Environmental Research (OHER), the manager and staff of the Chicago Field Office, and the authors colleagues. Emphasized are the progress and accomplishments of the year, rather than future plans or expectations. The technical summaries are grouped according to the following seven general program areas: environmental radiation and radioactivity; radiation transport and dosimetry; environmental radon, thoron, and related aerosols; atmospheric and surface pollutant studies related to global climate change; atmospheric chemistry; metrology, consultation, and emergency response; environmental management. EML's mission is to address important scientific questions concerning human health and environmental impacts. Through its multidisciplinary staff, EML conducts experimental and theoretical research on radioactive and other energy-related pollutants, and provides DOE and other federal agencies with the in-house capability to respond effectively and efficiently with regard to quality assurance activities, environmental issues and related national security issues

Note: Measurement system for the radiative forcing of greenhouse gases in a laboratory scale

Energy Technology Data Exchange (ETDEWEB)

Kawamura, Yoshiyuki [Department of Intelligent Mechanical Engineering, Fukuoka Institute of Technology, 3-30-1 Wajirohigashi, Higashiku, Fukuoka 811-0295 (Japan)

2016-01-15

The radiative forcing of the greenhouse gases has been studied being based on computational simulations or the observation of the real atmosphere meteorologically. In order to know the greenhouse effect more deeply and to study it from various viewpoints, the study on it in a laboratory scale is important. We have developed a direct measurement system for the infrared back radiation from the carbon dioxide (CO{sub 2}) gas. The system configuration is similar with that of the practical earth-atmosphere-space system. Using this system, the back radiation from the CO{sub 2} gas was directly measured in a laboratory scale, which roughly coincides with meteorologically predicted value.

Note: Measurement system for the radiative forcing of greenhouse gases in a laboratory scale.

Science.gov (United States)

Kawamura, Yoshiyuki

2016-01-01

The radiative forcing of the greenhouse gases has been studied being based on computational simulations or the observation of the real atmosphere meteorologically. In order to know the greenhouse effect more deeply and to study it from various viewpoints, the study on it in a laboratory scale is important. We have developed a direct measurement system for the infrared back radiation from the carbon dioxide (CO2) gas. The system configuration is similar with that of the practical earth-atmosphere-space system. Using this system, the back radiation from the CO2 gas was directly measured in a laboratory scale, which roughly coincides with meteorologically predicted value.

Environmental Audit of the Environmental Measurements Laboratory (EML)

International Nuclear Information System (INIS)

1992-02-01

This document contains the findings identified during the Environmental Audit of the Environmental Measurements Laboratory (EML), conducted from December 2 to 13, 1991. The Audit included the EML facility located in a fifth-floor General Services Administration (GSA) office building located in New York City, and a remote environmental monitoring station located in Chester, New Jersey. The scope of this Environmental Audit was comprehensive, covering all areas of environmental activities and waste management operations, with the exception of the National Environmental Policy Act (NEPA), which is the responsibility of the DOE Headquarters Office of NEPA Oversight. Compliance with applicable Federal, state, and local requirements; applicable DOE Orders; and internal facility requirements was addressed

Dosimeter calibration facilities and methods at the Radiation Measurement Laboratory of the Centre d'etudes nucleaires, Grenoble

International Nuclear Information System (INIS)

Choudens, H. de; Herbaut, Y.; Haddad, A.; Giroux, J.; Rouillon, J.; CEA Centre d'Etudes Nucleaires de Grenoble, 38

1975-01-01

At the Centre d'etudes nucleaires, Grenoble, the Radiation Measurement Laboratory, which forms part of the Environmental Protection and Research Department, serves the entire Centre for purposes of dosimetry and the calibration of dose meters. The needs of radiation protection are such that one must have facilities for checking periodically the calibration of radiation-monitoring instruments and developing special dosimetry techniques. It was thought a good idea to arrange for the dosimetry and radiation protection team to assist other groups working at the Centre - in particular, the staff of the biology and radiobiology laboratories - and also bodies outside the framework of the French Commissariat a l'energie atomique. Thus, technical collaboration has been established with, for example, Grenoble's Centre hospitalier universitaire (university clinic), which makes use of the facilities and skills available at the Radiation Measurement Laboratory for solving special dosimetry problems. With the Laboratory's facilities it is possible to calibrate dose meters for gamma, beta and neutron measurements

Silicon photomultipliers for the detection of VUV scintillation light in LXe for the nEXO experiment

Energy Technology Data Exchange (ETDEWEB)

Ziegler, Tobias; Jamil, Ako; Bayerlein, Reimund; Hoessl, Juergen; Hufschmidt, Patrick; Schneider, Judith; Wagenpfeil, Michael; Wrede, Gerrit; Anton, Gisela; Michel, Thilo [Erlangen Centre for Astroparticle Physics, Erlangen 91058 (Germany)

2016-07-01

The future nEXO (next Enriched Xenon Observatory) experiment with a single phase TPC design will use about 4 m{sup 2} of SiPMs for the detection of the VUV (vacuum ultraviolet) scintillation light (λ=175 nm) from LXe to search for the neutrinoless double beta (0νββ) decay of {sup 136}Xe. Commercially available SiPMs are not sensitive to ultraviolet light, because of an antireflective coating on top of the sensitive area. In addition, they suffer from relatively high dark count rate at room temperature and correlated avalanches, such as crosstalk and afterpulsing. The core criteria, for having an energy resolution of about 1% (σ) at the Q-value of the 0νββ decay of {sup 136}Xe (2457.8 keV), are a photon detection efficiency (PDE) of at least 15% at 175 nm and a correlated avalanche probability (CAP) of less than 20% at -100 C. We considered different approaches for optimizing both PDE and CAP. These improved SiPMs from several vendors were tested in different test setups at temperatures of about -100 C with respect to the criteria required in the nEXO experiment.

Brominated Tyrosine and Polyelectrolyte Multilayer Analysis by Laser Desorption VUV Postionization and Secondary Ion Mass Spectrometry

Energy Technology Data Exchange (ETDEWEB)

University of Illinois at Chicago; Blaze, Melvin M. T.; Takahashi, Lynelle; Zhou, Jia; Ahmed, Musahid; Gasper, Gerald; Pleticha, F. Douglas; Hanley, Luke

2011-03-14

The small molecular analyte 3,5-dibromotyrosine (Br2Y) and chitosan-alginate polyelectrolyte multilayers (PEM) with and without adsorbed Br2Y were analyzed by laser desorption postionization mass spectrometry (LDPI-MS). LDPI-MS using 7.87 eV laser and tunable 8 ? 12.5 eV synchrotron vacuum ultraviolet (VUV) radiation found that desorption of clusters from Br2Y films allowed detection by≤8 eV single photon ionization. Thermal desorption and electronic structure calculations determined the ionization energy of Br2Y to be ~;;8.3?0.1 eV and further indicated that the lower ionization energies of clusters permitted their detection at≤8 eV photon energies. However, single photon ionization could only detect Br2Y adsorbed within PEMs when using either higher photon energies or matrix addition to the sample. All samples were also analyzed by 25 keV Bi3 + secondary ion mass spectrometry (SIMS), with the negative ion spectra showing strong parent ion signal which complemented that observed by LDPI-MS. The negative ion SIMS depended strongly on the high electron affinity of this specific analyte and the analyte?s condensed phase environment.

Laboratory Measurements of Charging of Apollo 17 Lunar Dust Grains by Low Energy Electrons

Science.gov (United States)

Abbas, Mian M.; Tankosic, Dragana; Spann, James F.; Dube, Michael J.; Gaskin, Jessica

2007-01-01

It is well recognized that the charging properties of individual micron/sub-micron size dust grains by various processes are expected to be substantially different from the currently available measurements made on bulk materials. Solar UV radiation and the solar wind plasma charge micron size dust grains on the lunar surface with virtually no atmosphere. The electrostatically charged dust grains are believed to be levitated and transported long distances over the lunar terminator from the day to the night side. The current models do not fully explain the lunar dust phenomena and laboratory measurements are needed to experimentally determine the charging properties of lunar dust grains. An experimental facility has been developed in the Dusty Plasma Laboratory at NASA Marshall Space Flight Center MSFC for investigating the charging properties of individual micron/sub-micron size positively or negatively charged dust grains by levitating them in an electrodynamic balance in simulated space environments. In this paper, we present laboratory measurements on charging of Apollo 17 individual lunar dust grains by low energy electron beams in the 5-100 eV energy range. The measurements are made by levitating Apollo 17 dust grains of 0.2 to 10 micrometer diameters, in an electrodynamic balance and exposing them to mono-energetic electron beams. The charging rates and the equilibrium potentials produced by direct electron impact and by secondary electron emission processes are discussed.

Cataclastic effects in rock salt laboratory and in situ measurements

International Nuclear Information System (INIS)

Gramberg, J.; Roest, J.P.A.

1984-01-01

The aim of the research is the determination of eventual cataclastic effects in environmental rock salt of a heated part of a vertical deep test bore hole, a model for HLW disposal. Known cataclastic systems from hard rock mining and rock salt mines will form the starting point for the explanation of convergence of underground cavity walls. In rock salt, however, different elements seem to prevail: crystal plasticity and micro-cataclasis. The environmental measurements at the deep bore hole have to be carried out from a distance. To this end the acoustic micro-seismic method will be a suitable one. The appropriate equipment for micro-seismic cross hole measurement is designed, constructed and tested in the laboratory as well as underground. Acoustic velocity data form a crucial point. A micro-seismic acoustic P-wave model, adapted to the process of structural changes, is developed. P-wave velocity measurements in rock salt cubes in the laboratory are described. An underground cross hole measurement in the wall of a gallery with semi-circular section is treated and analysed. A conclusion was that, in this case, no macro-cataclasis (systematic large fractures) will be involved in the process of gallery convergence, but that the mechanism proved to be a combination of crystal plasticity and micro-cataclasis. The same mechanism might be expected to be present in the environmental rock salt of the HLW-disposal deep bore hole. As a result this environmental rock salt might be expected to be impermeable. A plan for the application of the developed equipment during the heating test on the ECN-deep-bore-hole is shown. A theory on ''disking'' or ''rim cracks'' is presented in an annex

VUV Fourier-transform absorption study of the Lyman and Werner bands in D2

Science.gov (United States)

de Lange, Arno; Dickenson, Gareth D.; Salumbides, Edcel J.; Ubachs, Wim; de Oliveira, Nelson; Joyeux, Denis; Nahon, Laurent

2012-06-01

An extensive survey of the D2 absorption spectrum has been performed with the high-resolution VUV Fourier-transform spectrometer employing synchrotron radiation. The frequency range of 90 000-119 000 cm-1 covers the full depth of the potential wells of the B sideset{^1}{+u}{Σ}, B^' } sideset{^1}{+u}{Σ}, and C 1Πu electronic states up to the D(1s) + D(2ℓ) dissociation limit. Improved level energies of rovibrational levels have been determined up to respectively v = 51, v = 13, and v = 20. Highest resolution is achieved by probing absorption in a molecular gas jet with slit geometry, as well as in a liquid helium cooled static gas cell, resulting in line widths of ≈0.35 cm-1. Extended calibration methods are employed to extract line positions of D2 lines at absolute accuracies of 0.03 cm-1. The D 1Πu and B^' ' } sideset{^1}{+u}{Σ} electronic states correlate with the D(1s) + D(3ℓ) dissociation limit, but support a few vibrational levels below the second dissociation limit, respectively, v = 0-3 and v = 0-1, and are also included in the presented study. The complete set of resulting level energies is the most comprehensive and accurate data set for D2. The observations are compared with previous studies, both experimental and theoretical.

A tangentially viewing VUV TV system for the DIII-D divertor

International Nuclear Information System (INIS)

Nilson, D.G.; Ellis, R.; Fenstermacher, M.E.; Brewis, G.; Jalufka, N.

1998-07-01

A video camera system capable of imaging VUV emission in the 120--160 nm wavelength range, from the entire divertor region in the DIII-D tokamak, was designed. The new system has a tangential view of the divertor similar to an existing tangential camera system which has produced two dimensional maps of visible line emission (400--800 nm) from deuterium and carbon in the divertor region. However, the overwhelming fraction of the power radiated by these elements is emitted by resonance transitions in the ultraviolet, namely the C IV line at 155.0 nm and Ly-α line at 121.6 nm. To image the ultraviolet light with an angular view including the inner wall and outer bias ring in DIII-D, a 6-element optical system (f/8.9) was designed using a combination of reflective and refractive optics. This system will provide a spatial resolution of 1.2 cm in the object plane. An intermediate UV image formed in a secondary vacuum is converted to the visible by means of a phosphor plate and detected with a conventional CID camera (30 ms framing rate). A single MgF 2 lens serves as the vacuum interface between the primary and secondary vacuums; a second lens must be inserted in the secondary vacuum to correct the focus at 155 nm. Using the same tomographic inversion method employed for the visible TV, they reconstruct the poloidal distribution of the UV divertor light. The grain size of the phosphor plate and the optical system aberrations limit the best focus spot size to 60 microm at the CID plane. The optical system is designed to withstand 350 C vessel bakeout, 2 T magnetic fields, and disruption-induced accelerations of the vessel

A VUV detection system for the direct photonic identification of the first excited isomeric state of "2"2"9Th

International Nuclear Information System (INIS)

Seiferle, B.; Von der Wense, L.; Thirolf, P.G.; Laatiaoui, M.

2016-01-01

With an expected energy of 7.6(5) eV, "2"2"9Th possesses the lowest excited nuclear state in the landscape of all presently known nuclei. The energy corresponds to a wavelength of about 160 nm and would conceptually allow for an optical laser excitation of a nuclear transition. We report on a VUV optical detection system that was designed for the direct detection of the isomeric ground-state transition of "2"2"9Th. "2"2"9"("m") Th ions originating from a "2"3"3U α-recoil source are collected on a micro electrode that is placed in the focus of an annular parabolic mirror. The latter is used to parallelize the UV fluorescence that may emerge from the isomeric ground-state transition of "2"2"9Th. The parallelized light is then focused by a second annular parabolic mirror onto a CsI-coated position-sensitive MCP detector behind the mirror exit. To achieve a high signal-to-background ratio, a small spot size on the MCP detector needs to be achieved. Besides extensive ray-tracing simulations of the optical setup, we present a procedure for its alignment, as well as test measurements using a D_2 lamp, where a focal-spot size of ∼100 μm has been achieved. Assuming a purely photonic decay, a signal-to-background ratio of ∼7000:1 could be achieved. (authors)

Directional Degradation of Spectralon Diffuser Under Ionizing Radiation for Calibration of Space-Based Sensors

Science.gov (United States)

Georgiev, G. T.; Butler, J. J.; Kowalewski, M. G.; Ding, L.

2012-01-01

Assessment of the effect of Vacuum Ultra Violet (VUV) irradiation on the Bidirectional Reflectance Distribution Function (BRDF) of Spectralon is presented in this paper. The sample was a 99% white Spectralon calibration standard irradiated with VUV source positioned at 60o off the irradiation direction for a total of 20 hours. The BRDF before and after VUV irradiation was measured and compared at number of wavelengths in the UV, VIS and IR. Non-isotropic directional degradation of Spectralon diffuser under ionizing radiation was detected at different BRDF measurement geometries primarily at UV spectral range. The 8o directional/hemispherical reflectance of the same sample was also measured and compared from 200nm to 2500nm. Index Terms BRDF, Reflectance, Multiangular, Spectralon, Remote Sensing

Investigation and Analysis of Hemoglobin A1c Measurement Systems' Performance for 135 Laboratories in China

Directory of Open Access Journals (Sweden)

Hai-Jian Zhao

2017-01-01

Conclusions: This study indicated that, although participating laboratories were laboratories with better performance in China, the performances were still unsatisfactory. Actions should be taken to improve HbA1c measurement performance before we can include HbA1c assays in diabetes diagnosis in China.

Measurement of the fast neutron background at the China Jinping Underground Laboratory

Science.gov (United States)

Du, Q.; Lin, S. T.; Liu, S. K.; Tang, C. J.; Wang, L.; Wei, W. W.; Wong, H. T.; Xing, H. Y.; Yue, Q.; Zhu, J. J.

2018-05-01

We report on the measurements of the fluxes and spectra of the environmental fast neutron background at the China Jinping Underground Laboratory (CJPL) with a rock overburden of about 6700 meters water equivalent, using a liquid scintillator detector doped with 0.5% gadolinium. The signature of a prompt nuclear recoil followed by a delayed high energy γ-ray cascade is used to identify neutron events. The large energy deposition of the delayed γ-rays from the (n , γ) reaction on gadolinium, together with the excellent n- γ discrimination capability provides a powerful background suppression which allows the measurement of a low intensity neutron flux. The neutron flux of (1 . 51 ± 0 . 03(stat .) ± 0 . 10(syst .)) × 10-7cm-2s-1 in the energy range of 1-10 MeV in the Hall A of CJPL was measured based on 356 days of data. In the same energy region, measurement with the same detector placed in a room surrounding with one meter thick polyethylene shielding gives a significantly lower flux of (4 . 9 ± 0 . 9(stat .) ± 0 . 5(syst .)) × 10-9cm-2s-1 with 174 days of data. This represents a measurement of the lowest environmental fast neutron background among the underground laboratories in the world, prior to additional experiment-specific attenuation. Additionally, the fast neutron spectra both in the Hall A and the polyethylene room were reconstructed with the help of GEANT4 simulations.

Laboratory Activity on Sample Handling and Maintaining a Laboratory Notebook through Simple pH Measurements

Science.gov (United States)

Erdmann, Mitzy A.; March, Joe L.

2016-01-01

Sample handling and laboratory notebook maintenance are necessary skills but can seem abstract if not presented to students in context. An introductory exercise focusing on proper sample handling, data collection and laboratory notebook keeping for the general chemistry laboratory was developed to emphasize the importance of keeping an accurate…

An automated image analysis system to measure and count organisms in laboratory microcosms.

Directory of Open Access Journals (Sweden)

François Mallard

Full Text Available 1. Because of recent technological improvements in the way computer and digital camera perform, the potential use of imaging for contributing to the study of communities, populations or individuals in laboratory microcosms has risen enormously. However its limited use is due to difficulties in the automation of image analysis. 2. We present an accurate and flexible method of image analysis for detecting, counting and measuring moving particles on a fixed but heterogeneous substrate. This method has been specifically designed to follow individuals, or entire populations, in experimental laboratory microcosms. It can be used in other applications. 3. The method consists in comparing multiple pictures of the same experimental microcosm in order to generate an image of the fixed background. This background is then used to extract, measure and count the moving organisms, leaving out the fixed background and the motionless or dead individuals. 4. We provide different examples (springtails, ants, nematodes, daphnia to show that this non intrusive method is efficient at detecting organisms under a wide variety of conditions even on faintly contrasted and heterogeneous substrates. 5. The repeatability and reliability of this method has been assessed using experimental populations of the Collembola Folsomia candida. 6. We present an ImageJ plugin to automate the analysis of digital pictures of laboratory microcosms. The plugin automates the successive steps of the analysis and recursively analyses multiple sets of images, rapidly producing measurements from a large number of replicated microcosms.

Environmental Measurements Laboratory, annual report 1995

Energy Technology Data Exchange (ETDEWEB)

Krey, P.W.; Heit, M. [eds.

1996-07-01

This report summarizes the activities of the Environmental Measurements Laboratory (EML) for the calendar year 1995 and serves as an annual report to the Director of the Office of Energy Research (ER), the Associate Director and staff of the Office of Health and Environmental Research (OHER), the Manager and staff of the Chicago Operations Office, and our colleagues. Emphasized are the progress and accomplishments of the year, rather than future plans or expectations. The technical summaries are grouped according to the following seven research program areas: (1) Environmental Radiation and Radioactivity; (2) Radiation Transport and Dosimetry; (3) Environmental Radon, Thoron, and Related Aerosols; (4) Atmospheric and Surface Pollutant Studies Related to Global Climate Change; (5) Atmospheric Chemistry; and (6) Metrology, Consultation, and Emergency Response Environmental Management The mission of EML is to address important scientific questions concerning human health and environmental impacts. Through its multidisciplinary staff, EML conducts experimental and theoretical research on radioactive and other energy-related pollutants and provides DOE and other federal agencies with the in-house capability to respond effectively and efficiently with regard to quality assurance activities, environmental issues, and related national security issues.

Environmental Measurements Laboratory, annual report 1995

International Nuclear Information System (INIS)

Krey, P.W.; Heit, M.

1996-07-01

This report summarizes the activities of the Environmental Measurements Laboratory (EML) for the calendar year 1995 and serves as an annual report to the Director of the Office of Energy Research (ER), the Associate Director and staff of the Office of Health and Environmental Research (OHER), the Manager and staff of the Chicago Operations Office, and our colleagues. Emphasized are the progress and accomplishments of the year, rather than future plans or expectations. The technical summaries are grouped according to the following seven research program areas: (1) Environmental Radiation and Radioactivity; (2) Radiation Transport and Dosimetry; (3) Environmental Radon, Thoron, and Related Aerosols; (4) Atmospheric and Surface Pollutant Studies Related to Global Climate Change; (5) Atmospheric Chemistry; and (6) Metrology, Consultation, and Emergency Response Environmental Management The mission of EML is to address important scientific questions concerning human health and environmental impacts. Through its multidisciplinary staff, EML conducts experimental and theoretical research on radioactive and other energy-related pollutants and provides DOE and other federal agencies with the in-house capability to respond effectively and efficiently with regard to quality assurance activities, environmental issues, and related national security issues

Technique and equipment for measuring volume activity of radon in the air of radon laboratories and clinics

International Nuclear Information System (INIS)

Vorob'ev, I.B.; Krivokhatskij, A.S.; Nekrasov, E.V.; Nikolaev, V.A.; Potapov, V.G.; Terent'ev, M.V.

1990-01-01

Usability of a new equipment-technique combination for measuring radon activity in the air of radon laboratories and balneological clinics is studied. The complex includes nitrate-cellulose detector, radon chamber, Aist, Istra type spark counters and technique of spark counting. The method sensitivity is 50 Bqxm 3 , the error is 30%. Usability and advisability of track method in radon laboratories and balneological clinics for simultaneous measurement in several points of integral volumetric radon activities are confirmred. The method permits to carry out rapid and accurate bulk investigations. The results of determining mean volumetric radon activity in the air in different points of radon laboratory and radon clinics are presented

Understanding Women's Subjective Sexual Arousal Within the Laboratory: Definition, Measurement, and Manipulation.

Science.gov (United States)

Handy, Ariel B; Stanton, Amelia M; Meston, Cindy M

2018-04-01

Subjective sexual arousal (SSA) is positive, cognitive engagement in sexual activity. SSA is considered an important aspect of the sexual experience, as it has been found to facilitate sexual activity and, in situations of chronically low or absent arousal, potentially cause distress. Despite the clinical implications of SSA, a thorough review of how to manipulate SSA has yet to be conducted. To review the state of knowledge about SSA in women, including its definition, measurement, and the outcomes of studies attempting to manipulate SSA within a laboratory setting. A comprehensive search of the electronic databases of PubMed and PsycINFO was conducted. The generated list of articles was reviewed and duplicates were removed. Individual articles were assessed for inclusion and, when appropriate, relevant content was extracted. The potential effects of various manipulations of SSA in a laboratory setting was the main outcome. 44 studies were included in this review. Manipulations were grouped into 3 primary categories: pharmacological (n = 16), cognitive (n = 22), and those based on changes to the autonomic nervous system (n = 6). Results suggest that cognitive manipulation is the most effective method of increasing SSA. Altering the relative balance of the 2 branches of the autonomic nervous system (the sympathetic nervous system and the parasympathetic nervous system) also appears to be a promising avenue for increasing SSA. This review supports the use of cognitive manipulation for increasing women's SSA in a laboratory setting. Avenues for future research and recommendations for clinicians are discussed. Handy AB, Stanton AM, Meston CM. Understanding Women's Subjective Sexual Arousal Within the Laboratory: Definition, Measurement, and Manipulation. Sex Med Rev 2018;6:201-216. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Laboratory Measurement of the Brighter-fatter Effect in an H2RG Infrared Detector

OpenAIRE

Plazas, A. A.; Shapiro, C.; Smith, R.; Huff, E.; Rhodes, J.

2018-01-01

The "brighter-fatter" (BF) effect is a phenomenon (originally discovered in charge coupled devices) in which the size of the detector point spread function (PSF) increases with brightness. We present, for the first time, laboratory measurements demonstrating the existence of the effect in a Hawaii-2RG HgCdTe near infrared (NIR) detector. We use the Precision Projector Laboratory, a JPL facility for emulating astronomical observations with UV/VIS/NIR detectors, to project about 17,000 point so...

The procedures manual of the Environmental Measurements Laboratory. Volume 2, 28. edition

Energy Technology Data Exchange (ETDEWEB)

Chieco, N.A. [ed.

1997-02-01

This report contains environmental sampling and analytical chemistry procedures that are performed by the Environmental Measurements Laboratory. The purpose of environmental sampling and analysis is to obtain data that describe a particular site at a specific point in time from which an evaluation can be made as a basis for possible action.

Conception of the Instrument Calibration Laboratory of Ionizing Radiation Measurement (LACIMRI) of CTMSP - Sao Paulo, SP

International Nuclear Information System (INIS)

Silva, Raimundo Dias da; Kibrit, Eduardo

2009-01-01

The present work describes the phases of implantation of calibration laboratory of ionizing radiation measurement instruments at the CTMSP, Sao Paulo, in a priory approved by CNEN, Brazil. That laboratory will allow and enhance the present metrological capacity for the attendance to the growing demand for calibration services of the instruments

A single-shot nonlinear autocorrelation approach for time-resolved physics in the vacuum ultraviolet spectral range

International Nuclear Information System (INIS)

Rompotis, Dimitrios

2016-02-01

In this work, a single-shot temporal metrology scheme operating in the vacuum-extreme ultraviolet spectral range has been designed and experimentally implemented. Utilizing an anti-collinear geometry, a second-order intensity autocorrelation measurement of a vacuum ultraviolet pulse can be performed by encoding temporal delay information on the beam propagation coordinate. An ion-imaging time-of-flight spectrometer, offering micrometer resolution has been set-up for this purpose. This instrument enables the detection of a magnified image of the spatial distribution of ions exclusively generated by direct two-photon absorption in the combined counter-propagating pulse focus and thus obtain the second-order intensity autocorrelation measurement on a single-shot basis. Additionally, an intense VUV light source based on high-harmonic generation has been experimentally realized. It delivers intense sub-20 fs Ti:Sa fifth-harmonic pulses utilizing a loose-focusing geometry in a long Ar gas cell. The VUV pulses centered at 161.8 nm reach pulse energies of 1.1 μJ per pulse, while the corresponding pulse duration is measured with a second-order, fringe-resolved autocorrelation scheme to be 18 ± 1 fs on average. Non-resonant, two-photon ionization of Kr and Xe and three-photon ionization of Ne verify the fifth-harmonic pulse intensity and indicate the feasibility of multi-photon VUV pump/VUV probe studies of ultrafast atomic and molecular dynamics. Finally, the extended functionally of the counter-propagating pulse metrology approach is demonstrated by a single-shot VUV pump/VUV probe experiment aiming at the investigation of ultrafast dissociation dynamics of O 2 excited in the Schumann-Runge continuum at 162 nm.

Laboratory Measurements of the 940, 1130, and 1370 nm Water Vapor Absorption Band Profiles

Science.gov (United States)

Giver, Lawrence P.; Gore, Warren J.; Pilewskie, P.; Freedman, R. S.; Chackerian, C., Jr.; Varanasi, P.

2001-01-01

We have used the solar spectral flux radiometer (SSFR) flight instrument with the Ames 25 meter base-path White cell to obtain about 20 moderate resolution (8 nm) pure water vapor spectra from 650 to 1650 nm, with absorbing paths from 806 to 1506 meters and pressures up to 14 torr. We also obtained a set at 806 meters with several different air-broadening pressures. Model simulations were made for the 940, 1130, and 1370 nm absorption bands for some of these laboratory conditions using the Rothman, et al HITRAN-2000 linelist. This new compilation of HITRAN includes new intensity measurements for the 940 nm region. We compared simulations for our spectra of this band using HITRAN-2000 with simulations using the prior HITRAN-1996. The simulations of the 1130 nm band show about 10% less absorption than we measured. There is some evidence that the total intensity of this band is about 38% stronger than the sum of the HITRAN line intensities in this region. In our laboratory conditions the absorption depends approximately on the square root of the intensity. Thus, our measurements agree that the band is stronger than tabulated in HITRAN, but by about 20%, substantially less than the published value. Significant differences have been shown between Doppler-limited resolution spectra of the 1370 nm band obtained at the Pacific Northwest National Laboratory and HITRAN simulations. Additional new intensity measurements in this region are continuing to be made. We expect the simulations of our SSFR lab data of this band will show the relative importance of improving the HITRAN line intensities of this band for atmospheric measurements.

Contribution to the RMTC in the field of tank calibration and measurements - the TAMSCA laboratory

International Nuclear Information System (INIS)

Hunt, B.A.; Landat, D.; Caviglia, M.; Silvapestana, L.

1999-01-01

The Russian Methodological and Training Centre (RMTC) is being established for training of personnel from the various Russian and CIS nuclear facilities organizations in the control and accountancy methods, utilised in EURATOM and in the IAEA. Under the project equipment and support will be provided in a number of areas, namely containment and surveillance, training, passive/active neutron assay and mass/volume methodologies. For the latter a mass/volume measurement laboratory - a Tank Measurements and Calibration Laboratory (TAMSCA) is being set-up in IPPE, Obninsk. The goal is to upgrade the methodology within the Russian Federation in the application of mass/volume measurement techniques and render a facility suitable adapted to carrying out training courses with specific orientation for the nuclear inspectors and operators of nuclear facilities for nuclear accountancy and control [ru

Design of UHV chamber assembly and mirror mounts for high resolution VUV beam line at INDUS-1

International Nuclear Information System (INIS)

Saksena, G.D.; Sinha, A.K.; Bhattacharya, S.S.

1993-01-01

The reflecting optical system is designed for the high resolution VUV spectroscopy facility to be installed at INDUS-1. The fore-optics system consists of three cylindrical mirrors (M1, M2 and M3) to accept a 60 mrad (horizontal) x 6 mrad (vertical) diverging synchrotron beam from the storage ring in order to focus the image on the entrance slit of the vacuum spectrometer located at 13 m from the source point. In this paper we present some important details regarding mechanical design of the high resolution beam line consisting of mirror mounts, UHV chambers, associated mechanisms and beam pipes. The mirrors are mounted in an adjustable three point kinematic holder. In addition, these mounts are provided with a multi-plane alignment provision. Mirror mounts are placed inside VHV chambers which are provided with three translational and two rotational movements to facilitate initial as well as final on-line fine-tuned alignments. Beam pipes are connected to the VHV chambers through flanged bellows. Chambers, associated mechanisms, beam pipes with its non-rigid support and related pumping stations are positioned in the support structure rigidly. (author). 2 figs

Measuring Dynamic Kidney Function in an Undergraduate Physiology Laboratory

Science.gov (United States)

Medler, Scott; Harrington, Frederick

2013-01-01

Most undergraduate physiology laboratories are very limited in how they treat renal physiology. It is common to find teaching laboratories equipped with the capability for high-resolution digital recordings of physiological functions (muscle twitches, ECG, action potentials, respiratory responses, etc.), but most urinary laboratories still rely on…

Photometrics Laboratory

Data.gov (United States)

Federal Laboratory Consortium — Purpose:The Photometrics Laboratory provides the capability to measure, analyze and characterize radiometric and photometric properties of light sources and filters,...

Laboratory Evaluation of Air Flow Measurement Methods for Residential HVAC Returns

Energy Technology Data Exchange (ETDEWEB)

Walker, Iain; Stratton, Chris

2015-07-01

This project improved the accuracy of air flow measurements used in commissioning California heating and air conditioning systems in Title 24 (Building and Appliance Efficiency Standards), thereby improving system performance and efficiency of California residences. The research team at Lawrence Berkeley National Laboratory addressed the issue that typical tools used by contractors in the field to test air flows may not be accurate enough to measure return flows used in Title 24 applications. The team developed guidance on performance of current diagnostics as well as a draft test method for use in future evaluations. The series of tests performed measured air flow using a range of techniques and devices. The measured air flows were compared to reference air flow measurements using inline air flow meters built into the test apparatus. The experimental results showed that some devices had reasonable results (typical errors of 5 percent or less) but others had much bigger errors (up to 25 percent).

Implementing and measuring the level of laboratory service integration in a program setting in Nigeria.

Directory of Open Access Journals (Sweden)

Henry Mbah

Full Text Available The surge of donor funds to fight HIV&AIDS epidemic inadvertently resulted in the setup of laboratories as parallel structures to rapidly respond to the identified need. However these parallel structures are a threat to the existing fragile laboratory systems. Laboratory service integration is critical to remedy this situation. This paper describes an approach to quantitatively measure and track integration of HIV-related laboratory services into the mainstream laboratory services and highlight some key intervention steps taken, to enhance service integration.A quantitative before-and-after study conducted in 122 Family Health International (FHI360 supported health facilities across Nigeria. A minimum service package was identified including management structure; trainings; equipment utilization and maintenance; information, commodity and quality management for laboratory integration. A check list was used to assess facilities at baseline and 3 months follow-up. Level of integration was assessed on an ordinal scale (0 = no integration, 1 = partial integration, 2 = full integration for each service package. A composite score grading expressed as a percentage of total obtainable score of 14 was defined and used to classify facilities (≤ 80% FULL, 25% to 79% PARTIAL and <25% NO integration. Weaknesses were noted and addressed.We analyzed 9 (7.4% primary, 104 (85.2% secondary and 9 (7.4% tertiary level facilities. There were statistically significant differences in integration levels between baseline and 3 months follow-up period (p<0.01. Baseline median total integration score was 4 (IQR 3 to 5 compared to 7 (IQR 4 to 9 at 3 months follow-up (p = 0.000. Partial and fully integrated laboratory systems were 64 (52.5% and 0 (0.0% at baseline, compared to 100 (82.0% and 3 (2.4% respectively at 3 months follow-up (p = 0.000.This project showcases our novel approach to measure the status of each laboratory on the integration continuum.

Field Measurements Indicate Unexpected, Serious Underestimation of Mussel Heart Rates and Thermal Tolerance by Laboratory Studies.

Directory of Open Access Journals (Sweden)

Morgana Tagliarolo

Full Text Available Attempts to predict the response of species to long-term environmental change are generally based on extrapolations from laboratory experiments that inevitably simplify the complex interacting effects that occur in the field. We recorded heart rates of two genetic lineages of the brown mussel Perna perna over a full tidal cycle in-situ at two different sites in order to evaluate the cardiac responses of the two genetic lineages present on the South African coast to temperature and the immersion/emersion cycle. "Robomussel" temperature loggers were used to monitor thermal conditions at the two sites over one year. Comparison with live animals showed that robomussels provided a good estimate of mussel body temperatures. A significant difference in estimated body temperatures was observed between the sites and the results showed that, under natural conditions, temperatures regularly approach or exceed the thermal limits of P. perna identified in the laboratory. The two P. perna lineages showed similar tidal and diel patterns of heart rate, with higher cardiac activity during daytime immersion and minimal values during daytime emersion. Comparison of the heart rates measured in the field with data previously measured in the laboratory indicates that laboratory results seriously underestimate heart rate activity, by as much as 75%, especially during immersion. Unexpectedly, field estimates of body temperatures indicated an ability to tolerate temperatures considered lethal on the basis of laboratory measurements. This suggests that the interaction of abiotic conditions in the field does not necessarily raise vulnerability to high temperatures.

Measurement of low radioactivity in underground laboratories by means of many-dimensional spectrometry

International Nuclear Information System (INIS)

Niese, Siegfried

2008-01-01

In this contribution beside the possibilities for the measurements in underground laboratories also the application of the many-dimensional spectrometry is considered, under which coincidence, anticoincidence, and time-resolving spectrometric are to be understood. Very extensively the interaction of cosmic radiation with matter is considered

Photoionization sensors for non-invasive medical diagnostics

Science.gov (United States)

Mustafaev, Aleksandr; Rastvorova, Iuliia; Khobnya, Kristina; Podenko, Sofia

2016-09-01

The analysis of biomarkers can help to identify the significant number of diseases: lung cancer, tuberculosis, diabetes, high levels of stress, psychosomatic disorders etc. To implement continuous monitoring of the state of human health, compact VUV photoionization detector with current-voltage measurement is designed by Saint-Petersburg Mining University Plasma Research Group. This sensor is based on the patented method of stabilization of electric parameters - CES (Collisional Electron Spectroscopy). During the operation at atmospheric pressure VUV photoionization sensor measures the energy of electrons, produced in the ionization with the resonance photons, whose wavelength situated in the vacuum ultraviolet (VUV). A special software was developed to obtain the second-order derivative of the I-U characteristics, taken by the VUV sensor, to construct the energy spectra of the characteristic electrons. VUV photoionization detector has an unique set of parameters: small size (10*10*1 mm), low cost, wide range of recognizable molecules, as well as accuracy, sufficient for using this instrument for the medical purposes. This device can be used for non-invasive medical diagnostics without compromising the quality of life, for control of environment and human life. Work supported by Foundation for Assistance to Small Innovative Enterprises in Science and Technology.

Measurement accuracy of weighing and tipping-bucket rainfall intensity gauges under dynamic laboratory testing

Science.gov (United States)

Colli, M.; Lanza, L. G.; La Barbera, P.; Chan, P. W.

2014-07-01

The contribution of any single uncertainty factor in the resulting performance of infield rain gauge measurements still has to be comprehensively assessed due to the high number of real world error sources involved, such as the intrinsic variability of rainfall intensity (RI), wind effects, wetting losses, the ambient temperature, etc. In recent years the World Meteorological Organization (WMO) addressed these issues by fostering dedicated investigations, which revealed further difficulties in assessing the actual reference rainfall intensity in the field. This work reports on an extensive assessment of the OTT Pluvio2 weighing gauge accuracy when measuring rainfall intensity under laboratory dynamic conditions (time varying reference flow rates). The results obtained from the weighing rain gauge (WG) were also compared with a MTX tipping-bucket rain gauge (TBR) under the same test conditions. Tests were carried out by simulating various artificial precipitation events, with unsteady rainfall intensity, using a suitable dynamic rainfall generator. Real world rainfall data measured by an Ogawa catching-type drop counter at a field test site located within the Hong Kong International Airport (HKIA) were used as a reference for the artificial rain generation system. Results demonstrate that the differences observed between the laboratory and field performance of catching-type gauges are only partially attributable to the weather and operational conditions in the field. The dynamics of real world precipitation events is responsible for a large part of the measurement errors, which can be accurately assessed in the laboratory under controlled environmental conditions. This allows for new testing methodologies and the development of instruments with enhanced performance in the field.

Photoelectron photoion molecular beam spectroscopy

International Nuclear Information System (INIS)

Trevor, D.J.

1980-12-01

The use of supersonic molecular beams in photoionization mass spectroscopy and photoelectron spectroscopy to assist in the understanding of photoexcitation in the vacuum ultraviolet is described. Rotational relaxation and condensation due to supersonic expansion were shown to offer new possibilities for molecular photoionization studies. Molecular beam photoionization mass spectroscopy has been extended above 21 eV photon energy by the use of Stanford Synchrotron Radiation Laboratory (SSRL) facilities. Design considerations are discussed that have advanced the state-of-the-art in high resolution vuv photoelectron spectroscopy. To extend gas-phase studies to 160 eV photon energy, a windowless vuv-xuv beam line design is proposed

IAEA intercomparison exercises of thyroid measurement: performance of Latin American and Caribbean laboratories

International Nuclear Information System (INIS)

Dantas, B.M.; Dantas, A.L.A.; Cruz-Suarez, R.

2016-01-01

131 I is widely used in Latin America and Caribbean Region in the field of nuclear medicine and has been recognised as one of the main sources of potential intake of radionuclides by the staff. The In Vivo Monitoring laboratory of the Institute for Radiation Protection and Dosimetry (IRD-CNEN-Brazil) organised three intercomparison exercises (2005, 2009 and 2013) in the scope of IAEA technical cooperation projects RLA9049 and RLA9066 aimed to disseminate and harmonise the technique for measuring 131 I in the human thyroid. The number of participants in Latin America increased from 9 to 20 institutions from 7 and 13 countries, respectively, over the last 10 y. The participants have improved significantly their ability on the in vivo measurement technique. In the 2013 round all laboratories which reported results presented performances in an acceptable range according to the ISO criteria indicating the benefit of such exercises in the region. (authors)

The NRPB Chilton Calibration Laboratory for radiological protection measurements

International Nuclear Information System (INIS)

Iles, W.J.

1982-01-01

The Calibration Laboratory in NRPB Headquarters is intended as an authoritative reference laboratory for all aspects of radiation protection level instrument calibrations for X-, gamma and beta radiations and to be complementary to the national primary standards of the National Physical Laboratory. The gamma ray, filtered X-ray, fluorescence X-ray and beta ray facilities are described. (U.K.)

Geomechanics Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The Geomechanics Laboratory allows its users to measure rock properties under a wide range of simulated service conditions up to very high pressures and complex load...

Low-Level Plutonium Bioassay Measurements at the Lawrence Livermore National Laboratory

Energy Technology Data Exchange (ETDEWEB)

Hamilton, T; Brown, T; Hickman, D; Marchetti, A; Williams, R; Kehl, S

2007-06-18

Plutonium-239 ({sup 239}Pu) and plutonium-240 ({sup 240}Pu) are important alpha emitting radionuclides contained in radioactive debris from nuclear weapons testing. {sup 239}Pu and {sup 240}Pu are long-lived radionuclides with half-lives of 24,400 years and 6580 years, respectively. Concerns over human exposure to plutonium stem from knowledge about the persistence of plutonium isotopes in the environment and the high relative effectiveness of alpha-radiation to cause potential harm to cells once incorporated into the human body. In vitro bioassay tests have been developed to assess uptakes of plutonium based on measured urinary excretion patterns and modeled metabolic behaviors of the absorbed radionuclides. Systemic plutonium absorbed by the deep lung or from the gastrointestinal tract after ingestion is either excreted or distributed to other organs, primarily to the liver and skeleton, where it is retained for biological half-times of around 20 and 50 years, respectively. Dose assessment and atoll rehabilitation programs in the Marshall Islands have historically given special consideration to residual concentrations of plutonium in the environment even though the predicted dose from inhalation and/or ingestion of plutonium accounts for less than 5% of the annual effective dose from exposure to fallout contamination. Scientists from the Lawrence Livermore National Laboratory (LLNL) have developed a state-of-the-art bioassay test to assess urinary excretion rates of plutonium from Marshallese populations. This new heavy-isotope measurement system is based on Accelerator Mass Spectrometry (AMS). The AMS system at LLNL far exceeds the standard measurement requirements established under the latest United States Department of Energy (DOE) regulation, 10CFR 835, for occupational monitoring of plutonium, and offers several advantages over classical as well as competing new technologies for low-level detection and measurement of plutonium isotopes. The United States

Results from laboratory and field testing of nitrate measuring spectrophotometers

Science.gov (United States)

Snazelle, Teri T.

2015-01-01

Five ultraviolet (UV) spectrophotometer nitrate analyzers were evaluated by the U.S. Geological Survey (USGS) Hydrologic Instrumentation Facility (HIF) during a two-phase evaluation. In Phase I, the TriOS ProPs (10-millimeter (mm) path length), Hach NITRATAX plus sc (5-mm path length), Satlantic Submersible UV Nitrate Analyzer (SUNA, 10-mm path length), and S::CAN Spectro::lyser (5-mm path length) were evaluated in the HIF Water-Quality Servicing Laboratory to determine the validity of the manufacturer's technical specifications for accuracy, limit of linearity (LOL), drift, and range of operating temperature. Accuracy specifications were met in the TriOS, Hach, and SUNA. The stock calibration of the S::CAN required two offset adjustments before the analyzer met the manufacturer's accuracy specification. Instrument drift was observed only in the S::CAN and was the result of leaching from the optical path insert seals. All tested models, except for the Hach, met their specified LOL in the laboratory testing. The Hach's range was found to be approximately 18 milligrams nitrogen per liter (mg-N/L) and not the manufacturer-specified 25 mg-N/L. Measurements by all of the tested analyzers showed signs of hysteresis in the operating temperature tests. Only the SUNA measurements demonstrated excessive noise and instability in temperatures above 20 degrees Celsius (°C). The SUNA analyzer was returned to the manufacturer at the completion of the Phase II field deployment evaluation for repair and recalibration, and the performance of the sensor improved significantly.

Comparison of a New Cobinamide-Based Method to a Standard Laboratory Method for Measuring Cyanide in Human Blood

Science.gov (United States)

Swezey, Robert; Shinn, Walter; Green, Carol; Drover, David R.; Hammer, Gregory B.; Schulman, Scott R.; Zajicek, Anne; Jett, David A.; Boss, Gerry R.

2013-01-01

Most hospital laboratories do not measure blood cyanide concentrations, and samples must be sent to reference laboratories. A simple method is needed for measuring cyanide in hospitals. The authors previously developed a method to quantify cyanide based on the high binding affinity of the vitamin B12 analog, cobinamide, for cyanide and a major spectral change observed for cyanide-bound cobinamide. This method is now validated in human blood, and the findings include a mean inter-assay accuracy of 99.1%, precision of 8.75% and a lower limit of quantification of 3.27 µM cyanide. The method was applied to blood samples from children treated with sodium nitroprusside and it yielded measurable results in 88 of 172 samples (51%), whereas the reference laboratory yielded results in only 19 samples (11%). In all 19 samples, the cobinamide-based method also yielded measurable results. The two methods showed reasonable agreement when analyzed by linear regression, but not when analyzed by a standard error of the estimate or paired t-test. Differences in results between the two methods may be because samples were assayed at different times on different sample types. The cobinamide-based method is applicable to human blood, and can be used in hospital laboratories and emergency rooms. PMID:23653045

Comparison of laboratory and field remote sensing methods to measure forage quality.

Science.gov (United States)

Guo, Xulin; Wilmshurst, John F; Li, Zhaoqin

2010-09-01

Recent research in range ecology has emphasized the importance of forage quality as a key indicator of rangeland condition. However, we lack tools to evaluate forage quality at scales appropriate for management. Using canopy reflectance data to measure forage quality has been conducted at both laboratory and field levels separately, but little work has been conducted to evaluate these methods simultaneously. The objective of this study is to find a reliable way of assessing grassland quality through measuring forage chemistry with reflectance. We studied a mixed grass ecosystem in Grasslands National Park of Canada and surrounding pastures, located in southern Saskatchewan. Spectral reflectance was collected at both in-situ field level and in the laboratory. Vegetation samples were collected at each site, sorted into the green grass portion, and then sent to a chemical company for measuring forage quality variables, including protein, lignin, ash, moisture at 135 °C, Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF), Total Digestible, Digestible Energy, Net Energy for Lactation, Net Energy for Maintenance, and Net Energy for Gain. Reflectance data were processed with the first derivative transformation and continuum removal method. Correlation analysis was conducted on spectral and forage quality variables. A regression model was further built to investigate the possibility of using canopy spectral measurements to predict the grassland quality. Results indicated that field level prediction of protein of mixed grass species was possible (r² = 0.63). However, the relationship between canopy reflectance and the other forage quality variables was not strong.

Comparison of Laboratory and Field Remote Sensing Methods to Measure Forage Quality

Directory of Open Access Journals (Sweden)

Zhaoqin Li

2010-09-01

Full Text Available Recent research in range ecology has emphasized the importance of forage quality as a key indicator of rangeland condition. However, we lack tools to evaluate forage quality at scales appropriate for management. Using canopy reflectance data to measure forage quality has been conducted at both laboratory and field levels separately, but little work has been conducted to evaluate these methods simultaneously. The objective of this study is to find a reliable way of assessing grassland quality through measuring forage chemistry with reflectance. We studied a mixed grass ecosystem in Grasslands National Park of Canada and surrounding pastures, located in southern Saskatchewan. Spectral reflectance was collected at both in-situ field level and in the laboratory. Vegetation samples were collected at each site, sorted into the green grass portion, and then sent to a chemical company for measuring forage quality variables, including protein, lignin, ash, moisture at 135 ºC, Neutral Detergent Fiber (NDF, Acid Detergent Fiber (ADF, Total Digestible, Digestible Energy, Net Energy for Lactation, Net Energy for Maintenance, and Net Energy for Gain. Reflectance data were processed with the first derivative transformation and continuum removal method. Correlation analysis was conducted on spectral and forage quality variables. A regression model was further built to investigate the possibility of using canopy spectral measurements to predict the grassland quality. Results indicated that field level prediction of protein of mixed grass species was possible (r2 = 0.63. However, the relationship between canopy reflectance and the other forage quality variables was not strong.

Application of peer instruction in the laboratory task of measuring the effective mass of a spring

Science.gov (United States)

Zhang, Chun-Ling; Hou, Zhen-Yu; Si, Yu-Chang; Wen, Xiao-Qing; Tang, Lei

2017-11-01

Peer instruction (PI) is an effective interactive approach to teaching and learning that has principally been used to modify the experience of learning in traditional physics lecture settings. This article further illustrates how the concept of PI can be effectively applied in the physics student laboratory setting. The setting used is a laboratory task that calls for the measurement of the effective mass of the spring of a Jolly balance. Through PI the students gain a better understanding of what is meant by the construct ‘effective mass of a spring’, and thereby competently work out how the mass, shape, wire diameter, and number of turns of the spring can all affect the effective mass of the spring. Furthermore, using stopwatches the students were also able to appreciate how recorded times at the equilibrium position had greater uncertainty than measurements made at the maximum displacement. This led to their calculations of the effective mass of the spring being impressively close to the theoretical value. Such laboratory tasks are extremely challenging to introductory level students and the success attained by the students in this study indicates that there is much potential in the application of PI in laboratory settings. PI should be used to teach in the laboratory and results should be reported in order for our community to build on these experiences. This article is a contribution to that effort.

Effects of plasma and vacuum-ultraviolet exposure on the mechanical properties of low-k porous organosilicate glass

Science.gov (United States)

X. Guo; J.E. Jakes; S. Banna; Y. Nishi; J.L. Shohet

2014-01-01

The effects of plasma exposure and vacuum-ultraviolet (VUV) irradiation on the mechanical properties of low-k porous organosilicate glass (SiCOH) dielectric films were investigated. Nanoindentation measurements were made on SiCOH films before and after exposure to an electron-cyclotron-resonance plasma or a monochromatic synchrotron VUV beam, to determine the changes...

Error prevention at a radon measurement service laboratory

International Nuclear Information System (INIS)

Cohen, B.L.; Cohen, F.

1989-01-01

This article describes the steps taken at a high volume counting laboratory to avoid human, instrument, and computer errors. The laboratory analyzes diffusion barrier charcoal adsorption canisters which have been used to test homes and commercial buildings. A series of computer and human cross-checks are utilized to assure that accurate results are reported to the correct client

X-ray measurement of residual stress in metals at Chalk River Nuclear Laboratories

International Nuclear Information System (INIS)

Winegar, J.E.

1980-06-01

X-ray diffraction is used at CRNL to measure residual stress in metals. This report summarizes the basic principles of stress measurement, and reviews factors affecting accuracy of measurement. The technique and equipment described were developed at CRNL to give reliable measurements. Accuracy of measurement is achieved by using fixed-count step-scanning and by computer analysis of intensity data using a cubic spline curve smoothing routine. Specific reference is made to the measurement of residual stress in Inconel-600 and Incoloy-800 boiler tubing. Because it measures stress in thin surface layers, the X-ray method can also be used to measure the depth profile of stresses. As there are no standardized procedures for measuring residual stress, this report will be useful both to those unfamiliar with the measurement of residual stress and to those already making such measurements in other laboratories. (auth)

Inter-laboratory comparison of HITU power measurement methods and capabilities

International Nuclear Information System (INIS)

Jenderka, K V; Durando, G; Karaboece, B; Rajagopal, S; Shaw, A

2011-01-01

High Intensity Therapeutic Ultrasound (HITU) is gaining in importance among the spectrum of therapeutic options to combat cancer. HITU has already been approved and is in clinical use for the treatment of organs like the prostate, the liver and the uterus. Nevertheless, the metrology of the applied high power ultrasound fields, and in consequence, reliable treatment planning and monitoring, is still a challenge. As part of a European Metrology Research Programme project, the four National Metrology Institutes from the UK, Germany, Italy and Turkey conducted an inter-laboratory comparison of their power measurement capabilities at power levels of 5, 25, 75 and 150 W each at frequencies of 1.1, 1.5 and 3.3 MHz. The task was to measure the total, time-averaged ultrasonic output power, emitted by the circulated transducers under specified electrical excitation conditions into an anechoic water load, and the actual rms transducer input voltage. The output value to be reported was the electro-acoustic radiation conductance including the associated standard and expanded uncertainties. Several different measurement techniques were applied to gain further insight into HITU power measurement. The deviations from the calculated comparison reference value found for the different techniques are discussed and conclusions for the further improvement of measuring procedures are drawn.

Inter-laboratory comparison of HITU power measurement methods and capabilities

Energy Technology Data Exchange (ETDEWEB)

Jenderka, K V [Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig (Germany); Durando, G [Istituto Nazionale di Ricerca Metrologica (INRIM), Strada delle Cacce 91, 10135 Torino (Italy); Karaboece, B [Tuebitak Ulusal Metroloji Enstituesue (UME), P.K. 54 41470 Gebze-Kocaeli (Turkey); Rajagopal, S; Shaw, A, E-mail: kvjend@ieee.org [National Physical Laboratory (NPL), Hampton Road, Teddington, TW11 0LW (United Kingdom)

2011-02-01

High Intensity Therapeutic Ultrasound (HITU) is gaining in importance among the spectrum of therapeutic options to combat cancer. HITU has already been approved and is in clinical use for the treatment of organs like the prostate, the liver and the uterus. Nevertheless, the metrology of the applied high power ultrasound fields, and in consequence, reliable treatment planning and monitoring, is still a challenge. As part of a European Metrology Research Programme project, the four National Metrology Institutes from the UK, Germany, Italy and Turkey conducted an inter-laboratory comparison of their power measurement capabilities at power levels of 5, 25, 75 and 150 W each at frequencies of 1.1, 1.5 and 3.3 MHz. The task was to measure the total, time-averaged ultrasonic output power, emitted by the circulated transducers under specified electrical excitation conditions into an anechoic water load, and the actual rms transducer input voltage. The output value to be reported was the electro-acoustic radiation conductance including the associated standard and expanded uncertainties. Several different measurement techniques were applied to gain further insight into HITU power measurement. The deviations from the calculated comparison reference value found for the different techniques are discussed and conclusions for the further improvement of measuring procedures are drawn.

Laboratory Measurements of Electrostatic Solitary Structures Generated by Beam Injection

International Nuclear Information System (INIS)

Lefebvre, Bertrand; Chen, Li-Jen; Gekelman, Walter; Pribyl, Patrick; Vincena, Stephen; Kintner, Paul; Pickett, Jolene; Chiang, Franklin; Judy, Jack

2010-01-01

Electrostatic solitary structures are generated by injection of a suprathermal electron beam parallel to the magnetic field in a laboratory plasma. Electric microprobes with tips smaller than the Debye length (λ De ) enabled the measurement of positive potential pulses with half-widths 4 to 25λ De and velocities 1 to 3 times the background electron thermal speed. Nonlinear wave packets of similar velocities and scales are also observed, indicating that the two descend from the same mode which is consistent with the electrostatic whistler mode and result from an instability likely to be driven by field-aligned currents.

Argonne National Laboratory's thermal plume measurements: instruments and techniques

International Nuclear Information System (INIS)

Van Loon, L.S.; Frigo, A.A.; Paddock, R.A.

1977-12-01

Instrumentation and techniques were developed at Argonne National Laboratory for measuring the three-dimensional temperature structure of thermal plumes from power plants, along with the limnological, meteorological, and plant operating conditions affecting their behavior. The equipment and procedures were designed to provide field data for use in evaluating predictive models that describe thermal plume behavior, and over 100 sets of these data have been collected. The instrument systems and techniques employed in a typical thermal discharge survey are highly integrated. Continuous monitoring of ambient and plant conditions is coupled with plume mapping from a moving survey boat. The instantaneous location of the boat together with subsurface temperature measurements from a towed thermistor chain provide a quasisynoptic view of the plume structure. Real-time, onboard display of the boat path and vertical temperatures supply feedback to investigators for determining the extent and spatial resolution of measurements required. The unique design, reliability, accuracy, calibration, and historical development of the components of these integrated systems are described. Survey system interfaces with data handling and processing techniques are also explained. Special supportive studies to investigate plume dynamics, values of eddy diffusivities, time-temperature histories of water parcels in thermal plumes, and rapid changes in plume shape are also described along with instrumentation used

Meta-audit of laboratory ISO accreditation inspections: measuring the old emperor's clothes.

Science.gov (United States)

Wilson, Ian G; Smye, Michael; Wallace, Ian J C

2016-02-01

Accreditation to ISO/IEC 17025 is required for EC official food control and veterinary laboratories by Regulation (EC) No. 882/2004. Measurements in hospital laboratories and clinics are increasingly accredited to ISO/IEC 15189. Both of these management standards arose from command and control military standards for factory inspection during World War II. They rely on auditing of compliance and have not been validated internally as assessment bodies require of those they accredit. Neither have they been validated to criteria outside their own ideology such as the Cochrane principles of evidence-based medicine which might establish whether any benefit exceeds their cost. We undertook a retrospective meta-audit over 14 years of internal and external laboratory audits that checked compliance with ISO 17025 in a public health laboratory. Most noncompliances arose solely from clauses in the standard and would not affect users. No effect was likely from 91% of these. Fewer than 1% of noncompliances were likely to have consequences for the validity of results or quality of service. The ISO system of compliance auditing has the performance characteristics of a poor screening test. It adds substantially to costs and generates more noise (false positives) than informative signal. Ethical use of resources indicates that management standards should not be used unless proven to deliver the efficacy, effectiveness, and value required of modern healthcare interventions. © 2015 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

The structural analysis of zinc borate glass by laboratory EXAFS and X-ray diffraction measurements

International Nuclear Information System (INIS)

Kajinami, Akihiko; Harada, Yasushi; Inoue, Shinsuke; Deki, Shigehito; Umesaki, Norimasa

1999-01-01

The structure of zinc borate glass has been investigated by laboratory EXAFS and X-ray diffraction measurement as preliminary investigations for the detailed study in SPring-8. The zinc borate glass was prepared in the range from 40 to 65 mol% of zinc oxide content. The X-ray diffraction was measured by horizontal θ-θ goniometer with 60 kV and 300 mA output of Mo target. The EXAFS of zinc borate glass was measured by laboratory EXAFS system with 20 kV, 100 mA output of Mo target for the K absorption edge of zinc atom. From the X-ray diffraction and the EXAFS measurements, it is found that the zinc ion is surrounded by four oxygen atoms and formed a tetrahedral structure whose (Zn-O) distance is about 2 A and that the structure is unchanged with the zinc oxide content. The diffraction data show that the neighboring structure of boron atom transforms from BO 4 tetrahedra to BO 3 tetragonal planar structure with increasing of the zinc oxide content. (author)

Analysis of bias in measurements of potassium, sodium and hemoglobin by an emergency department-based blood gas analyzer relative to hospital laboratory autoanalyzer results.

Directory of Open Access Journals (Sweden)

Jian Bo Zhang

Full Text Available The emergency departments (EDs of Chinese hospitals are gradually being equipped with blood gas machines. These machines, along with the measurement of biochemical markers by the hospital laboratory, facilitate the care of patients with severe conditions who present to the ED. However, discrepancies have been noted between the Arterial Blood Gas (ABG analyzers in the ED and the hospital laboratory autoanalyzer in relation to electrolyte and hemoglobin measurements. The present study was performed to determine whether the ABG and laboratory measurements of potassium, sodium, and hemoglobin levels are equivalent, and whether ABG analyzer results can be used to guide clinical care before the laboratory results become available.Study power analyses revealed that 200 consecutive patients who presented to our ED would allow this prospective single-center cohort study to detect significant differences between ABG- and laboratory-measured potassium, sodium, and hemoglobin levels. Paired arterial and venous blood samples were collected within 30 minutes. Arterial blood samples were measured in the ED by an ABL 90 FLEX blood gas analyzer. The biochemistry and blood cell counts of the venous samples were measured in the hospital laboratory. The potassium, sodium, and hemoglobin concentrations obtained by both methods were compared by using paired Student's t-test, Spearman's correlation, Bland-Altman plots, and Deming regression.The mean ABG and laboratory potassium values were 3.77±0.44 and 4.2±0.55, respectively (P<0.0001. The mean ABG and laboratory sodium values were 137.89±5.44 and 140.93±5.50, respectively (P<0.0001. The mean ABG and laboratory Hemoglobin values were 12.28±2.62 and 12.35±2.60, respectively (P = 0.24.Although there are the statistical difference and acceptable biases between ABG- and laboratory-measured potassium and sodium, the biases do not exceed USCLIA-determined limits. In parallel, there are no statistical differences and

Accuracy of finite-difference modeling of seismic waves : Simulation versus laboratory measurements

Science.gov (United States)

Arntsen, B.

2017-12-01

The finite-difference technique for numerical modeling of seismic waves is still important and for some areas extensively used.For exploration purposes is finite-difference simulation at the core of both traditional imaging techniques such as reverse-time migration and more elaborate Full-Waveform Inversion techniques.The accuracy and fidelity of finite-difference simulation of seismic waves are hard to quantify and meaningfully error analysis is really onlyeasily available for simplistic media. A possible alternative to theoretical error analysis is provided by comparing finite-difference simulated data with laboratory data created using a scale model. The advantage of this approach is the accurate knowledge of the model, within measurement precision, and the location of sources and receivers.We use a model made of PVC immersed in water and containing horizontal and tilted interfaces together with several spherical objects to generateultrasonic pressure reflection measurements. The physical dimensions of the model is of the order of a meter, which after scaling represents a model with dimensions of the order of 10 kilometer and frequencies in the range of one to thirty hertz.We find that for plane horizontal interfaces the laboratory data can be reproduced by the finite-difference scheme with relatively small error, but for steeply tilted interfaces the error increases. For spherical interfaces the discrepancy between laboratory data and simulated data is sometimes much more severe, to the extent that it is not possible to simulate reflections from parts of highly curved bodies. The results are important in view of the fact that finite-difference modeling is often at the core of imaging and inversion algorithms tackling complicatedgeological areas with highly curved interfaces.

Making Ultraviolet Spectro-Polarimetry Polarization Measurements with the MSFC Solar Ultraviolet Magnetograph Sounding Rocket

Science.gov (United States)

West, Edward; Cirtain, Jonathan; Kobayashi, Ken; Davis, John; Gary, Allen

2011-01-01

This paper will describe the Marshall Space Flight Center's Solar Ultraviolet Magnetograph Investigation (SUMI) sounding rocket program. This paper will concentrate on SUMI's VUV optics, and discuss their spectral, spatial and polarization characteristics. While SUMI's first flight (7/30/2010) met all of its mission success criteria, there are several areas that will be improved for its second and third flights. This paper will emphasize the MgII linear polarization measurements and describe the changes that will be made to the sounding rocket and how those changes will improve the scientific data acquired by SUMI.

Mars' Surface Radiation Environment Measured with the Mars Science Laboratory's Curiosity Rover

Science.gov (United States)

Hassler, Donald M.; Zeitlin, Cary; Wimmer-Schweingruber, Robert F.; Ehresmann, Bent; Rafkin, Scot; Eigenbrode, Jennifer L.; Brinza, David E.; Weigle, Gerald; Böttcher, Stephan; Böhm, Eckart; Burmeister, Soenke; Guo, Jingnan; Köhler, Jan; Martin, Cesar; Reitz, Guenther; Cucinotta, Francis A.; Kim, Myung-Hee; Grinspoon, David; Bullock, Mark A.; Posner, Arik; Gómez-Elvira, Javier; Vasavada, Ashwin; Grotzinger, John P.; MSL Science Team; Kemppinen, Osku; Cremers, David; Bell, James F.; Edgar, Lauren; Farmer, Jack; Godber, Austin; Wadhwa, Meenakshi; Wellington, Danika; McEwan, Ian; Newman, Claire; Richardson, Mark; Charpentier, Antoine; Peret, Laurent; King, Penelope; Blank, Jennifer; Schmidt, Mariek; Li, Shuai; Milliken, Ralph; Robertson, Kevin; Sun, Vivian; Baker, Michael; Edwards, Christopher; Ehlmann, Bethany; Farley, Kenneth; Griffes, Jennifer; Miller, Hayden; Newcombe, Megan; Pilorget, Cedric; Rice, Melissa; Siebach, Kirsten; Stack, Katie; Stolper, Edward; Brunet, Claude; Hipkin, Victoria; Léveillé, Richard; Marchand, Geneviève; Sánchez, Pablo Sobrón; Favot, Laurent; Cody, George; Steele, Andrew; Flückiger, Lorenzo; Lees, David; Nefian, Ara; Martin, Mildred; Gailhanou, Marc; Westall, Frances; Israël, Guy; Agard, Christophe; Baroukh, Julien; Donny, Christophe; Gaboriaud, Alain; Guillemot, Philippe; Lafaille, Vivian; Lorigny, Eric; Paillet, Alexis; Pérez, René; Saccoccio, Muriel; Yana, Charles; Armiens-Aparicio, Carlos; Rodríguez, Javier Caride; Blázquez, Isaías Carrasco; Gómez, Felipe Gómez; Hettrich, Sebastian; Malvitte, Alain Lepinette; Jiménez, Mercedes Marín; Martínez-Frías, Jesús; Martín-Soler, Javier; Martín-Torres, F. Javier; Jurado, Antonio Molina; Mora-Sotomayor, Luis; Caro, Guillermo Muñoz; López, Sara Navarro; Peinado-González, Verónica; Pla-García, Jorge; Manfredi, José Antonio Rodriguez; Romeral-Planelló, Julio José; Fuentes, Sara Alejandra Sans; Martinez, Eduardo Sebastian; Redondo, Josefina Torres; Urqui-O'Callaghan, Roser; Mier, María-Paz Zorzano; Chipera, Steve; Lacour, Jean-Luc; Mauchien, Patrick; Sirven, Jean-Baptiste; Manning, Heidi; Fairén, Alberto; Hayes, Alexander; Joseph, Jonathan; Squyres, Steven; Sullivan, Robert; Thomas, Peter; Dupont, Audrey; Lundberg, Angela; Melikechi, Noureddine; Mezzacappa, Alissa; Berger, Thomas; Matthia, Daniel; Prats, Benito; Atlaskin, Evgeny; Genzer, Maria; Harri, Ari-Matti; Haukka, Harri; Kahanpää, Henrik; Kauhanen, Janne; Kemppinen, Osku; Paton, Mark; Polkko, Jouni; Schmidt, Walter; Siili, Tero; Fabre, Cécile; Wray, James; Wilhelm, Mary Beth; Poitrasson, Franck; Patel, Kiran; Gorevan, Stephen; Indyk, Stephen; Paulsen, Gale; Gupta, Sanjeev; Bish, David; Schieber, Juergen; Gondet, Brigitte; Langevin, Yves; Geffroy, Claude; Baratoux, David; Berger, Gilles; Cros, Alain; d'Uston, Claude; Forni, Olivier; Gasnault, Olivier; Lasue, Jérémie; Lee, Qiu-Mei; Maurice, Sylvestre; Meslin, Pierre-Yves; Pallier, Etienne; Parot, Yann; Pinet, Patrick; Schröder, Susanne; Toplis, Mike; Lewin, Éric; Brunner, Will; Heydari, Ezat; Achilles, Cherie; Oehler, Dorothy; Sutter, Brad; Cabane, Michel; Coscia, David; Israël, Guy; Szopa, Cyril; Dromart, Gilles; Robert, François; Sautter, Violaine; Le Mouélic, Stéphane; Mangold, Nicolas; Nachon, Marion; Buch, Arnaud; Stalport, Fabien; Coll, Patrice; François, Pascaline; Raulin, François; Teinturier, Samuel; Cameron, James; Clegg, Sam; Cousin, Agnès; DeLapp, Dorothea; Dingler, Robert; Jackson, Ryan Steele; Johnstone, Stephen; Lanza, Nina; Little, Cynthia; Nelson, Tony; Wiens, Roger C.; Williams, Richard B.; Jones, Andrea; Kirkland, Laurel; Treiman, Allan; Baker, Burt; Cantor, Bruce; Caplinger, Michael; Davis, Scott; Duston, Brian; Edgett, Kenneth; Fay, Donald; Hardgrove, Craig; Harker, David; Herrera, Paul; Jensen, Elsa; Kennedy, Megan R.; Krezoski, Gillian; Krysak, Daniel; Lipkaman, Leslie; Malin, Michael; McCartney, Elaina; McNair, Sean; Nixon, Brian; Posiolova, Liliya; Ravine, Michael; Salamon, Andrew; Saper, Lee; Stoiber, Kevin; Supulver, Kimberley; Van Beek, Jason; Van Beek, Tessa; Zimdar, Robert; French, Katherine Louise; Iagnemma, Karl; Miller, Kristen; Summons, Roger; Goesmann, Fred; Goetz, Walter; Hviid, Stubbe; Johnson, Micah; Lefavor, Matthew; Lyness, Eric; Breves, Elly; Dyar, M. Darby; Fassett, Caleb; Blake, David F.; Bristow, Thomas; DesMarais, David; Edwards, Laurence; Haberle, Robert; Hoehler, Tori; Hollingsworth, Jeff; Kahre, Melinda; Keely, Leslie; McKay, Christopher; Wilhelm, Mary Beth; Bleacher, Lora; Brinckerhoff, William; Choi, David; Conrad, Pamela; Dworkin, Jason P.; Floyd, Melissa; Freissinet, Caroline; Garvin, James; Glavin, Daniel; Harpold, Daniel; Jones, Andrea; Mahaffy, Paul; Martin, David K.; McAdam, Amy; Pavlov, Alexander; Raaen, Eric; Smith, Michael D.; Stern, Jennifer; Tan, Florence; Trainer, Melissa; Meyer, Michael; Voytek, Mary; Anderson, Robert C.; Aubrey, Andrew; Beegle, Luther W.; Behar, Alberto; Blaney, Diana; Calef, Fred; Christensen, Lance; Crisp, Joy A.; DeFlores, Lauren; Ehlmann, Bethany; Feldman, Jason; Feldman, Sabrina; Flesch, Gregory; Hurowitz, Joel; Jun, Insoo; Keymeulen, Didier; Maki, Justin; Mischna, Michael; Morookian, John Michael; Parker, Timothy; Pavri, Betina; Schoppers, Marcel; Sengstacken, Aaron; Simmonds, John J.; Spanovich, Nicole; Juarez, Manuel de la Torre; Webster, Christopher R.; Yen, Albert; Archer, Paul Douglas; Jones, John H.; Ming, Douglas; Morris, Richard V.; Niles, Paul; Rampe, Elizabeth; Nolan, Thomas; Fisk, Martin; Radziemski, Leon; Barraclough, Bruce; Bender, Steve; Berman, Daniel; Dobrea, Eldar Noe; Tokar, Robert; Vaniman, David; Williams, Rebecca M. E.; Yingst, Aileen; Lewis, Kevin; Leshin, Laurie; Cleghorn, Timothy; Huntress, Wesley; Manhès, Gérard; Hudgins, Judy; Olson, Timothy; Stewart, Noel; Sarrazin, Philippe; Grant, John; Vicenzi, Edward; Wilson, Sharon A.; Hamilton, Victoria; Peterson, Joseph; Fedosov, Fedor; Golovin, Dmitry; Karpushkina, Natalya; Kozyrev, Alexander; Litvak, Maxim; Malakhov, Alexey; Mitrofanov, Igor; Mokrousov, Maxim; Nikiforov, Sergey; Prokhorov, Vasily; Sanin, Anton; Tretyakov, Vladislav; Varenikov, Alexey; Vostrukhin, Andrey; Kuzmin, Ruslan; Clark, Benton; Wolff, Michael; McLennan, Scott; Botta, Oliver; Drake, Darrell; Bean, Keri; Lemmon, Mark; Schwenzer, Susanne P.; Anderson, Ryan B.; Herkenhoff, Kenneth; Lee, Ella Mae; Sucharski, Robert; Hernández, Miguel Ángel de Pablo; Ávalos, Juan José Blanco; Ramos, Miguel; Malespin, Charles; Plante, Ianik; Muller, Jan-Peter; Navarro-González, Rafael; Ewing, Ryan; Boynton, William; Downs, Robert; Fitzgibbon, Mike; Harshman, Karl; Morrison, Shaunna; Dietrich, William; Kortmann, Onno; Palucis, Marisa; Sumner, Dawn Y.; Williams, Amy; Lugmair, Günter; Wilson, Michael A.; Rubin, David; Jakosky, Bruce; Balic-Zunic, Tonci; Frydenvang, Jens; Jensen, Jaqueline Kløvgaard; Kinch, Kjartan; Koefoed, Asmus; Madsen, Morten Bo; Stipp, Susan Louise Svane; Boyd, Nick; Campbell, John L.; Gellert, Ralf; Perrett, Glynis; Pradler, Irina; VanBommel, Scott; Jacob, Samantha; Owen, Tobias; Rowland, Scott; Atlaskin, Evgeny; Savijärvi, Hannu; García, César Martín; Mueller-Mellin, Reinhold; Bridges, John C.; McConnochie, Timothy; Benna, Mehdi; Franz, Heather; Bower, Hannah; Brunner, Anna; Blau, Hannah; Boucher, Thomas; Carmosino, Marco; Atreya, Sushil; Elliott, Harvey; Halleaux, Douglas; Rennó, Nilton; Wong, Michael; Pepin, Robert; Elliott, Beverley; Spray, John; Thompson, Lucy; Gordon, Suzanne; Newsom, Horton; Ollila, Ann; Williams, Joshua; Vasconcelos, Paulo; Bentz, Jennifer; Nealson, Kenneth; Popa, Radu; Kah, Linda C.; Moersch, Jeffrey; Tate, Christopher; Day, Mackenzie; Kocurek, Gary; Hallet, Bernard; Sletten, Ronald; Francis, Raymond; McCullough, Emily; Cloutis, Ed; ten Kate, Inge Loes; Kuzmin, Ruslan; Arvidson, Raymond; Fraeman, Abigail; Scholes, Daniel; Slavney, Susan; Stein, Thomas; Ward, Jennifer; Berger, Jeffrey; Moores, John E.

2014-01-01

The Radiation Assessment Detector (RAD) on the Mars Science Laboratory's Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment.

Mars' surface radiation environment measured with the Mars Science Laboratory's Curiosity rover.

Science.gov (United States)

Hassler, Donald M; Zeitlin, Cary; Wimmer-Schweingruber, Robert F; Ehresmann, Bent; Rafkin, Scot; Eigenbrode, Jennifer L; Brinza, David E; Weigle, Gerald; Böttcher, Stephan; Böhm, Eckart; Burmeister, Soenke; Guo, Jingnan; Köhler, Jan; Martin, Cesar; Reitz, Guenther; Cucinotta, Francis A; Kim, Myung-Hee; Grinspoon, David; Bullock, Mark A; Posner, Arik; Gómez-Elvira, Javier; Vasavada, Ashwin; Grotzinger, John P

2014-01-24

The Radiation Assessment Detector (RAD) on the Mars Science Laboratory's Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment.

The effect of noise in a performance measure on work motivation: A real effort laboratory experiment

NARCIS (Netherlands)

Sloof, R.; van Praag, C.M.

2008-01-01

This paper reports the results of an individual real effort laboratory experiment where subjects are paid for measured performance. Measured performance equals actual performance plus noise. We compare a stable environment where the noise is small with a volatile environment where the noise is

The effect of noise in a performance measure on work motivation: A real effort laboratory experiment

NARCIS (Netherlands)

Sloof, R.; van Praag, C.M.

2010-01-01

This paper reports the results of an individual real effort laboratory experiment where subjects are paid for measured performance. Measured performance equals actual performance plus noise. We compare a stable environment where the noise is small with a volatile environment where the noise is

Mechanical Measurements Laboratory

CERN Multimedia

Maximilien Brice

2007-01-01

The CERN mechanical measurements team check the sensors on one of the ATLAS inner detector end-caps using high precision measurement equipment. Remote checks like this must be made on these sensitive detector components before they can be transported to make sure that all systems are working correctly.

Hydraulic Hybrid and Conventional Parcel Delivery Vehicles' Measured Laboratory Fuel Economy on Targeted Drive Cycles

Energy Technology Data Exchange (ETDEWEB)

Lammert, M. P.; Burton, J.; Sindler, P.; Duran, A.

2014-10-01

This research project compares laboratory-measured fuel economy of a medium-duty diesel powered hydraulic hybrid vehicle drivetrain to both a conventional diesel drivetrain and a conventional gasoline drivetrain in a typical commercial parcel delivery application. Vehicles in this study included a model year 2012 Freightliner P100H hybrid compared to a 2012 conventional gasoline P100 and a 2012 conventional diesel parcel delivery van of similar specifications. Drive cycle analysis of 484 days of hybrid parcel delivery van commercial operation from multiple vehicles was used to select three standard laboratory drive cycles as well as to create a custom representative cycle. These four cycles encompass and bracket the range of real world in-use data observed in Baltimore United Parcel Service operations. The NY Composite cycle, the City Suburban Heavy Vehicle Cycle cycle, and the California Air Resources Board Heavy Heavy-Duty Diesel Truck (HHDDT) cycle as well as a custom Baltimore parcel delivery cycle were tested at the National Renewable Energy Laboratory's Renewable Fuels and Lubricants Laboratory. Fuel consumption was measured and analyzed for all three vehicles. Vehicle laboratory results are compared on the basis of fuel economy. The hydraulic hybrid parcel delivery van demonstrated 19%-52% better fuel economy than the conventional diesel parcel delivery van and 30%-56% better fuel economy than the conventional gasoline parcel delivery van on cycles other than the highway-oriented HHDDT cycle.

Comparison of the corrosion potential for stainless steel measured in-plant and in laboratory during BWR normal water chemistry conditions

International Nuclear Information System (INIS)

Molander, A.; Pein, K.; Tarkpea, P.; Takagi, Junichi; Karlberg, G.; Gott, K.

1998-01-01

To obtain reliable crack growth rate date for stainless steel in BWR environments careful laboratory simulation of the environmental conditions is necessary. In the plant the BWR normal water chemistry environment contains hydrogen peroxide, oxygen and hydrogen. However, in crack growth rate experiments in laboratories, the environment is normally simulated by adding 200 ppb oxygen to the high temperature water. Thus, as hydrogen peroxide is a more powerful oxidant than oxygen, it is to be expected that a lower corrosion potential will be measured in the laboratory than in the plant. To resolve this issue this work has been performed. In-plant and laboratory measurements have often been performed with somewhat different equipment, due to the special requirements concerning in-plant measurements. In this work such differences have been avoided and two identical sets of equipment for electrochemical measurements were built and used for measurements in-plant in a Swedish BWR and in high purity water in the laboratory. The host plant was Barsebaeck 1. Corrosion potential monitoring in-plant was performed under both NWC (Normal Water Chemistry) and HWC (Hydrogen Water Chemistry) conditions. This paper is, however, focused on NWC conditions. This is due to the fact, that the total crack growth obtained during a reactor cycle, can be determined by NWC conditions, even for plants running with HWC due to periodic stops in the hydrogen addition for turbine inspections or failure of the dosage or hydrogen production equipment. Thus, crack growth data for NWC is of great importance both for BWRs operating with HWC and NWC. Measurements in-plant and in the laboratory were performed during additions of oxygen and hydrogen peroxide to the autoclave systems. The corrosion potentials were compared for various conditions in the autoclaves, as well as versus in-plant in-pipe corrosion potentials. (J.P.N.)

[Laboratory accreditation and proficiency testing].

Science.gov (United States)

Kuwa, Katsuhiko

2003-05-01

ISO/TC 212 covering clinical laboratory testing and in vitro diagnostic test systems will issue the international standard for medical laboratory quality and competence requirements, ISO 15189. This standard is based on the ISO/IEC 17025, general requirements for competence of testing and calibration laboratories and ISO 9001, quality management systems-requirements. Clinical laboratory services are essential to patient care and therefore should be available to meet the needs of all patients and clinical personnel responsible for human health care. If a laboratory seeks accreditation, it should select an accreditation body that operates according to this international standard and in a manner which takes into account the particular requirements of clinical laboratories. Proficiency testing should be available to evaluate the calibration laboratories and reference measurement laboratories in clinical medicine. Reference measurement procedures should be of precise and the analytical principle of measurement applied should ensure reliability. We should be prepared to establish a quality management system and proficiency testing in clinical laboratories.

Laboratory calibrations of airborne gamma-ray spectrometers. Measurements and discussions of important parameters

International Nuclear Information System (INIS)

Korsbech, U.

1994-02-01

This report is the fourth of reports from The Department of Electrophysics covering measurement and interpretation of airborne gamma-spectrometry measurements. It describes different topics concerning the construction of a suitable calibration setup in the laboratory. The goal is to build a simple and cheap laboratory setup that can produce most of the gamma-ray data needed for an interpretation of spectra measured 50 to 120 m above ground level. A simple calibration setup has been build and tested. It may produce gamma-ray spectra similar to those measured in the air - from surface contamination with artificial nuclides and from 'bulk' natural radioactivity. It is possible to investigate the influence of the air above an aircraft carrying the detector (skyshine: scattering of gamma photons in the air above the detector). In order to reduce the influence of non-detected pile-up the count rates are kept low without reaching levels where the background spectra (to be subtracted) would cause unacceptable counting statistical fluctuations. Sources selected for the calibrations are heavy minerals sand (with thorium and uranium), potassium nitrate (with 40 K). These sources are 'bulk sources' of natural radioactivity. Cesium-137 has been selected as the basic artifical surface contamination nuclide. The report also discusses methods for comparing two spectra a priori assumed equal. Finally the properties of some materials that could be used as 'air-substitutes' in the calibration setup have been tested with respect to stability against moisture sorption. (au)

Development and application of a mobile laboratory for measuring emissions from diesel engines. 1. Regulated gaseous emissions.

Science.gov (United States)

Cocker, David R; Shah, Sandip D; Johnson, Kent; Miller, J Wayne; Norbeck, Joseph M

2004-04-01

Information about in-use emissions from diesel engines remains a critical issue for inventory development and policy design. Toward that end, we have developed and verified the first mobile laboratory that measures on-road or real-world emissions from engines at the quality level specified in the U.S. Congress Code of Federal Regulations. This unique mobile laboratory provides information on integrated and modal regulated gaseous emission rates and integrated emission rates for speciated volatile and semivolatile organic compounds and particulate matter during real-world operation. Total emissions are captured and collected from the HDD vehicle that is pulling the mobile laboratory. While primarily intended to accumulate data from HDD vehicles, it may also be used to measure emission rates from stationary diesel sources such as back-up generators. This paper describes the development of the mobile laboratory, its measurement capabilities, and the verification process and provides the first data on total capture gaseous on-road emission measurements following the California Air Resources Board (ARB) 4-mode driving cycle, the hot urban dynamometer driving schedule (UDDS), the modified 5-mode cycle, and a 53.2-mi highway chase experiment. NOx mass emission rates (g mi(-1)) for the ARB 4-mode driving cycle, the hot UDDS driving cycle, and the chase experimentwerefoundto exceed current emission factor estimates for the engine type tested by approximately 50%. It was determined that congested traffic flow as well as "off-Federal Test Procedure cycle" emissions can lead to significant increases in per mile NOx emission rates for HDD vehicles.

Measurement Tools for the Immersive Visualization Environment: Steps Toward the Virtual Laboratory.

Science.gov (United States)

Hagedorn, John G; Dunkers, Joy P; Satterfield, Steven G; Peskin, Adele P; Kelso, John T; Terrill, Judith E

2007-01-01

This paper describes a set of tools for performing measurements of objects in a virtual reality based immersive visualization environment. These tools enable the use of the immersive environment as an instrument for extracting quantitative information from data representations that hitherto had be used solely for qualitative examination. We provide, within the virtual environment, ways for the user to analyze and interact with the quantitative data generated. We describe results generated by these methods to obtain dimensional descriptors of tissue engineered medical products. We regard this toolbox as our first step in the implementation of a virtual measurement laboratory within an immersive visualization environment.

Environmental Measurements Laboratory annual report, calendar year 1980

International Nuclear Information System (INIS)

Volchok, H.L.

1981-05-01

The 1980 Annual Report is presented as a series of abstracts, organized by broad programmatic headings under the five technical Laboratory Divisions and one Branch. In addition, a short section appears at the end of the report describing the organization, staff, outside activities and our publications and presentations for the year. Research performaed by the Environmental Studies Division is reported under the following categories: high altitude sampling program, deposition and surface air, and the biosphere. Measurement methods research and air quality field studies are reported by the Aerosol Studies Division. The Radiation Physics Division reported research on radiation transport theory, radiation dosimetry, environmental radioactivity, and the assessment of non-nuclear energy technologies. Research in the Analytical Chemistry Division is reported on quality assurance, analytical support of research projects, analytical development for research projects, and programmatic research. The Instrumentation Division reported research on the development of instrumentation in various categories. The Applied Mathematics Branch reported results of programs for aerosol studies, analytical chemistry, environmental studies, and radiation physics

How compliant are technicians with universal safety measures in medical laboratories in Croatia?--A pilot study.

Science.gov (United States)

Dukic, Kristina; Zoric, Matea; Pozaic, Petra; Starcic, Jelena; Culjak, Marija; Saracevic, Andrea; Miler, Marijana

2015-01-01

This pilot study aimed to investigate the use of personal protective equipment (PPE) and compliance to the code of conduct (rules defined in institutional, governmental and professional guidelines) among laboratory technicians in Croatian medical laboratories. In addition, we explored the differences in compliance between participants of different age groups, laboratory ownership and accreditation status. An anonymous and voluntary survey with 15 questions was conducted among Croatian medical laboratory technicians (N=217). The questions were divided into two groups: demographic characteristics and the use of PPE. The questions of the second part were graded according to the Likert scale (1-4) and an overall score, shown as median and range (min-max), was calculated for each participant. Differences between the overall scores were tested for each group of participants. The majority of participants always wear protective clothes at work, 38.7% of them always wear gloves in daily routine, more than 30.0% consume food and almost half of them drink beverages at workplace. A significantly lower overall score was found for participants working in public compared to private laboratories (36 (16-40) vs. 40 (31-40), Plaboratory accreditation status (P=0.081). A considerable percentage of laboratory technicians in Croatian medical laboratories do not comply with safety measures. Lack of compliance is observed in all personnel regardless laboratory accreditation and participants' age. However, those working in private laboratories adhere more to the code of conduct.

Collection of measurement data in 2012 fiscal year at the Horonobe Underground Research Laboratory project

International Nuclear Information System (INIS)

Inagaki, Daisuke

2014-03-01

The Horonobe Underground Research Laboratory (URL) Project has being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host sedimentary formations at Horonobe, northern Hokkaido. The URL project consists of two major research areas, 'Geoscientific Research' and 'R and D on Geological Disposal Technologies', and proceeds in three overlapping phases, 'Phase I: Surface-based investigations', 'Phase II: Investigations during tunnel excavation' and 'Phase III: Investigations in the underground facilities', over a period of around 20 years. The Phase I geoscientific research was carried out from March 2001 to March 2006 in parallel with design and execution scheme on URL facilities. In addition, identifying key issues that need to be addressed in the Phase II/III investigations was planned. At the begining of the Phase II investigations, an investigation report titled 'Measurement Plan and Observational Construction Program on Shaft Excavation at the Horonobe Underground Research Laboratory Project' (hereinafter referred to as 'Observational Construction Program') and an investigation report titled 'Measurement Plan and Observational Construction Program on Drift Excavation at the Horonobe Underground Research Laboratory Project' were published. The Observational Construction Program summarizes the followings from the results of the Phase I investigations: measurements for safety and reasonable constructions, enhancement of shaft design and construction technologies and evaluation of appropriateness for the deep geological environment model estimated before shaft excavation. This report summarizes the measurements data acquired at the Ventilation Shaft, the East Shaft and the drifts in 2012 fiscal year based on the Observational Construction Program. The report summarizes the measurements data for the purpose of acquisition of the basic data

Performance testing of radiobioassay laboratories: in-vivo measurements, pilot study report

Energy Technology Data Exchange (ETDEWEB)

Robinson, A.V.; Fisher, D.R.; Reece, W.D.; MacLellan, J.A.

1986-10-01

This document describes a project to evaluate the in-vivo counting performance criteria of draft ANSI Standard N13.30, Performance Criteria for Radiobioassay. The draft ANSI Standard provides guidance to in-vivo counting facilities regarding the precision and accuracy of measurements for certain categories of commonly assayed radionuclides and critical regions of the body. The draft ANSI Standard was evaluated by conducting an intercomparison test involving a number of whole-body counting facilities. The testing involved three types of measurements: chest counting for detection of radioactive materials in the lung, whole-body counting for detection of uniformly distributed activity, and neck counting for detection of radioactive material concentrated in the thyroid. Results of the first-round intercomparison test are presented in this report. The appropriateness of the draft Standard performance criteria was judged by the measurement results reported by participating in-vivo counting facilities. The intercomparison testing showed that some laboratories had difficulty meeting the performance criteria specified in the draft ANSI Standard N13.30.

Performance testing of radiobioassay laboratories: in-vivo measurements, pilot study report

International Nuclear Information System (INIS)

Robinson, A.V.; Fisher, D.R.; Reece, W.D.; MacLellan, J.A.

1986-10-01

This document describes a project to evaluate the in-vivo counting performance criteria of draft ANSI Standard N13.30, Performance Criteria for Radiobioassay. The draft ANSI Standard provides guidance to in-vivo counting facilities regarding the precision and accuracy of measurements for certain categories of commonly assayed radionuclides and critical regions of the body. The draft ANSI Standard was evaluated by conducting an intercomparison test involving a number of whole-body counting facilities. The testing involved three types of measurements: chest counting for detection of radioactive materials in the lung, whole-body counting for detection of uniformly distributed activity, and neck counting for detection of radioactive material concentrated in the thyroid. Results of the first-round intercomparison test are presented in this report. The appropriateness of the draft Standard performance criteria was judged by the measurement results reported by participating in-vivo counting facilities. The intercomparison testing showed that some laboratories had difficulty meeting the performance criteria specified in the draft ANSI Standard N13.30

Measurements of cutter forces and cutter temperature of boring machine in Aespoe Hard Rock Laboratory

Energy Technology Data Exchange (ETDEWEB)

Zhang, Z.X.; Kou, S.Q.; Lindqvist, P.-A. [Luleaa Univ. of Technology (Sweden)

2001-04-01

This report presents both the testing methods used and the testing results obtained for cutter forces and cutter temperature during field boring in Aespoe Hard Rock Laboratory. In order to estimate the strains induced by cutter forces in the cutter shaft and choose proper transducers, first a numerical simulation was performed. The simulation results indicated that the cutter forces should be measurable by ordinary strain gauges. Furthermore, an independent three-direction loading system for laboratory calibration was set up to solve force-coupling problems appearing in field measurements. By means of the established measuring system, which was proved successfully in the laboratory, the normal forces, tangential forces, and side forces of two button cutters in the boring machine were measured in the field. In addition, the temperature in the shaft of the front cutter was measured. After the measurements of the cutter forces and cutter temperature, rock core samples were taken from the bottom and the wall of the testing borehole. Then the samples were cut, polished, and examined by means of the Scanning Electron Microscope (SEM). After that, the lengths of major cracks induced by the cutters in the rock samples were measured, and an approximate relationship between the length of the medium cracks and the relevant cutter forces was obtained. This relationship was compared with the theoretical relationship established before. Finally, according to the measured results, the cracked zones around the borehole were described. The results show that: (1) there are two kinds of cracked zones: one in the borehole wall and the other in the bottom of the borehole. The depth of the cracked zone in the borehole bottom is much larger than that in the borehole wall because the maximum normal force of the front cutter is always much larger than that of the gauge cutter. (2) Each cracked zone includes a densely cracked zone and all the longest medium cracks caused by mechanical

Workers’ Exposure to Nano-Objects with Different Dimensionalities in R&D Laboratories: Measurement Strategy and Field Studies

Directory of Open Access Journals (Sweden)

Fabio Boccuni

2018-01-01

Full Text Available With the increasing interest in the potential benefits of nanotechnologies, concern is still growing that they may present emerging risks for workers. Various strategies have been developed to assess the exposure to nano-objects and their agglomerates and aggregates (NOAA in the workplace, integrating different aerosol measurement instruments and taking into account multiple parameters that may influence NOAA toxicity. The present study proposes a multi-metric approach for measuring and sampling NOAA in the workplace, applied to three case studies in laboratories each dedicated to materials with different shapes and dimensionalities: graphene, nanowires, and nanoparticles. The study is part of a larger project with the aim of improving risk management tools in nanomaterials research laboratories. The harmonized methodology proposed by the Organization for Economic Cooperation and Development (OECD has been applied, including information gathering about materials and processes, measurements with easy-to-use and hand-held real-time devices, air sampling with personal samplers, and off-line analysis using scanning electron microscopy. Significant values beyond which an emission can be attributed to the NOAA production process were identified by comparison of the particle number concentration (PNC time series and the corresponding background levels in the three laboratories. We explored the relations between background PNC and microclimatic parameters. Morphological and elemental analysis of sampled filters was done to identify possible emission sources of NOAA during the production processes: rare particles, spherical, with average diameter similar to the produced NOAA were identified in the nanoparticles laboratory, so further investigation is recommended to confirm the potential for worker exposure. In conclusion, the information obtained should provide a valuable basis for improving risk management strategies in the laboratory at work.

Resonance ionization detection of combustion radicals

Energy Technology Data Exchange (ETDEWEB)

Cool, T.A. [Cornell Univ., Ithaca, NY (United States)

1993-12-01

Fundamental research on the combustion of halogenated organic compounds with emphasis on reaction pathways leading to the formation of chlorinated aromatic compounds and the development of continuous emission monitoring methods will assist in DOE efforts in the management and disposal of hazardous chemical wastes. Selective laser ionization techniques are used in this laboratory for the measurement of concentration profiles of radical intermediates in the combustion of chlorinated hydrocarbon flames. A new ultrasensitive detection technique, made possible with the advent of tunable VUV laser sources, enables the selective near-threshold photoionization of all radical intermediates in premixed hydrocarbon and chlorinated hydrocarbon flames.

Environmental Microbiology Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The Environmental Microbiology Laboratory, located in Bldg. 644 provides a dual-gas respirometer for measurement of oxygen consumption and carbon dioxide evolution...

Vertical muon intensity measured with MACRO at the Gran Sasso laboratory

International Nuclear Information System (INIS)

Ambrosio, M.; Antolini, R.; Auriemma, G.; Baker, R.; Baldini, A.; Barbarino, G.C.; Barish, B.C.; Battistoni, G.; Bellotti, R.; Bemporad, C.; Bernardini, P.; Bilokon, H.; Bisi, V.; Bloise, C.; Bower, C.; Bussino, S.; Cafagna, F.; Calicchio, M.; Campana, D.; Carboni, M.; Castellano, M.; Cecchini, S.; Cei, F.; Celio, P.; Chiarella, V.; Corona, A.; Coutu, S.; De Cataldo, G.; Dekhissi, H.; De Marzo, C.; De Mitri, I.; De Vincenzi, M.; Di Credico, A.; Erriquez, O.; Favuzzi, C.; Forti, C.; Fusco, P.; Giacomelli, G.; Giannini, G.; Giglietto, N.; Grassi, M.; Grillo, A.; Guarino, F.; Guarnaccia, P.; Gustavino, C.; Habig, A.; Hanson, K.; Hawthorne, A.; Heinz, R.; Hong, J.T.; Iarocci, E.; Katsavounidis, E.; Kearns, E.; Kyriazopoulou, S.; Lamanna, E.; Lane, C.; Levin, D.S.; Lipari, P.; Liu, R.; Longley, N.P.; Longo, M.J.; Lu, Y.; Ludlam, G.; Mancarella, G.; Mandrioli, G.; Margiotta-Neri, A.; Marini, A.; Martello, D.; Marzari-Chiesa, A.; Mazziotta, M.N.; Michael, D.G.; Mikheyev, S.; Miller, L.; Mittelbrunn, M.; Monacelli, P.; Montaruli, T.; Monteno, M.; Mufson, S.; Musser, J.; Nicolo, D.; Nolty, R.; Okada, C.; Orth, C.; Osteria, G.; Palamara, O.; Parlati, S.; Patera, V.; Patrizii, L.; Pazzi, R.; Peck, C.W.; Petrera, S.; Pignatano, N.D.; Pistilli, P.; Popa, V.; Raino, A.; Reynoldson, J.; Ronga, F.; Sanzgiri, A.; Sartogo, F.; Satriano, C.; Satta, L.; Scapparone, E.; Scholberg, K.; Sciubba, A.; Serra-Lugaresi, P.; Severi, M.; Sitta, M.; Spinelli, P.; Spinetti, M.; Spurio, M.; Steinberg, R.; Stone, J.L.; Sulak, L.R.; Surdo, A.; Tarle, G.; Tassoni, F.; Togo, V.; Valente, V.; Walter, C.W.; Webb, R.

1995-01-01

The vertical underground muon intensity has been measured in the slant depth range 3200--7000 hg cm -2 (standard rock) with the completed lower part of the MACRO detector at the Gran Sasso laboratory, using a large sample of data. These observations are used to compute the surface muon flux and the primary ''all-nucleon'' spectrum. An analysis of systematic uncertainties introduced by the interaction models in the atmosphere and the underground propagation of muons is presented. A comparison of our results with published data is also presented

Development of volumetric methane measurement instrument for laboratory scale anaerobic reactors

International Nuclear Information System (INIS)

Sahito, A.R.

2015-01-01

In the present study, a newly developed VMMI (volumetric Methane-Measuring Instrument) for laboratory scale anaerobic reactors is presented. The VMMI is a reliable, inexpensive, easy to construct, easy to use, corrosion resistant device that does not need maintenance, can measure a wide flow range of gas at varying pressure and temperature. As per the results of the error analysis, the accuracy of the VMMI is unilateral, i.e. -6.91 %. The calibration of VMMI was investigated and a linear variation was found; hence, in situ calibration is recommended for this type of instrument. As per chromatographic analysis, it absorbs almost 100% of the carbon dioxide present in the biogas, results only the methane, and thus eliminates the need of cost intensive composition analysis of biogas through gas chromatograph. (author)

Acoustic Technology Laboratory

Data.gov (United States)

Federal Laboratory Consortium — This laboratory contains an electro-magnetic worldwide data collection and field measurement capability in the area of acoustic technology. Outfitted by NASA Langley...

Photovoltaic Characterization Laboratory

Data.gov (United States)

Federal Laboratory Consortium — NIST's PV characterization laboratory is used to measure the electrical performance and opto-electronic properties of solar cells and modules. This facility consists...

Measuring the Bed Load velocity in Laboratory flumes using ADCP and Digital Cameras

Science.gov (United States)

Conevski, Slaven; Guerrero, Massimo; Rennie, Colin; Bombardier, Josselin

2017-04-01

Measuring the transport rate and apparent velocity of the bedload is notoriously hard and there is not a certain technique that would obtain continues data. There are many empirical models, based on the estimation of the shear stress, but only few involve direct measurement of the bed load velocity. The bottom tracking (BT) mode of an acoustic Doppler current profiler (ADCP) has been used many times to estimate the apparent velocity of the bed load. Herein is the basic idea, to exploit the bias of the BT signal towards the bed load movement and to calibrate this signal with traditional measuring techniques. These measurements are quite scarce and seldom reliable since there are not taken in controlled conditions. So far, no clear confirmation has been conducted in laboratory-controlled conditions that would attest the assumptions made in the estimation of the apparent bed load velocity, nor in the calibration of the empirical equations. Therefore, this study explores several experiments under stationary conditions, where the signal of the ADCP BT mode is recorded and compared to the bed load motion recorded by digital camera videography. The experiments have been performed in the hydraulic laboratories of Ottawa and Bologna, using two different ADCPs and two different high resolution cameras. In total, more then 30 experiments were performed for different sediment mixtures and different hydraulic conditions. In general, a good match is documented between the apparent bed load velocity measured by the ADCP and the videography. The slight deviation in single experiments can be explained by gravel particles inhomogeneity, difficult in reproducing the same hydro-sedimentological conditions and the randomness of the backscattering strength.

Permanent hydrophilic modification of polypropylene and poly(vinyl alcohol) films by vacuum ultraviolet radiation

Energy Technology Data Exchange (ETDEWEB)

Belmonte, Guilherme Kretzmann [Instituto de Química, Universidade Federal do Rio Grande do Sul (UFRGS), Avenida Bento Gonçalves 9500, 91501-970 Porto Alegre, RS (Brazil); Charles, German [Centro de Química Aplicada (CEQUIMAP), Facultad de Ciencias Químicas, Unversidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Edificio de Ciencias II, Ciudad Universitaria, Córdoba 5000 (Argentina); Strumia, Miriam Cristina [Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, IPQA-Conicet, Haya de la Torre y Medina Allende, Edificio de Ciencias II, Ciudad Universitaria, Córdoba 5000 (Argentina); Weibel, Daniel Eduardo, E-mail: danielw@iq.ufrgs.br [Instituto de Química, Universidade Federal do Rio Grande do Sul (UFRGS), Avenida Bento Gonçalves 9500, 91501-970 Porto Alegre, RS (Brazil)

2016-09-30

Highlights: • Polypropylene and Poly(vinyl alcohol) were surface modified by vacuum ultraviolet (VUV) irradiation. • The hydrophilicity of the treated films was permanent and resisted aging for several months. • Grafting of styrene monomer was only observed in the VUV irradiated regions. • The obtained results showed the potential in the use of VUV treatment for surface modification and processing of polymers which lack chromophores in the UV region. - Abstract: Polypropylene (PP) and Poly(vinyl alcohol) (PVA) both synthetics polymers but one of them biodegradable, were surface modified by vacuum ultraviolet (VUV) irradiation. After VUV irradiation in an inert nitrogen atmosphere, the films were exposed to oxygen gas. The treated films were characterized by water contact angle measurements (WCA), optical profilometry, FTIR-ATR, XPS, UPS and NEXAFS techniques. PP and PVA VUV-treated films reached superhydrophilic conditions (WCAs <10°) in about 30 min of irradiation under our experimental conditions. It was observed that when the WCAs reached about 35–40° the hydrophilicity was permanent in both polymers. These results contrasted with typical plasma treatments were a rapid hydrophobic recovery with aging time is usually observed. UPS and XPS data showed the presence of new functionalities on the PP and PVA surfaces that were assigned to COO, C=O, C−O and C=C functional groups. Finally, grafting of styrene (ST) as a typical monomer was tested on PP films. It was confirmed that only in the VUV irradiated region an efficient grafting of ST or polymerized ST was found. Outside the irradiated regions no ST grafted was observed. Our results showed the potential use of VUV treatment for surface modification and processing of polymers which lack chromophores in the UV region.

Exposure to electromagnetic fields from smart utility meters in GB; part I) laboratory measurements.

Science.gov (United States)

Peyman, Azadeh; Addison, Darren; Mee, Terry; Goiceanu, Cristian; Maslanyj, Myron; Mann, Simon

2017-05-01

Laboratory measurements of electric fields have been carried out around examples of smart meter devices used in Great Britain. The aim was to quantify exposure of people to radiofrequency signals emitted from smart meter devices operating at 2.4 GHz, and then to compare this with international (ICNIRP) health-related guidelines and with exposures from other telecommunication sources such as mobile phones and Wi-Fi devices. The angular distribution of the electric fields from a sample of 39 smart meter devices was measured in a controlled laboratory environment. The angular direction where the power density was greatest was identified and the equivalent isotropically radiated power was determined in the same direction. Finally, measurements were carried out as a function of distance at the angles where maximum field strengths were recorded around each device. The maximum equivalent power density measured during transmission around smart meter devices at 0.5 m and beyond was 15 mWm -2 , with an estimation of maximum duty factor of only 1%. One outlier device had a maximum power density of 91 mWm -2 . All power density measurements reported in this study were well below the 10 W m -2 ICNIRP reference level for the general public. Bioelectromagnetics. 2017;38:280-294. © 2017 Crown copyright. BIOELECTROMAGNETICS © 2017 Wiley Periodicals, Inc. © 2017 Crown copyright. BIOELECTROMAGNETICS © 2017 Wiley Periodicals, Inc.

Inter-laboratory comparisons of hexenuronic acid measurements in kraft eucalyptus pulps using a UV-Vis spectroscopic method

Science.gov (United States)

J.Y. Zhu; H.F Zhou; Chai X.S.; Donna Johannes; Richard Pope; Cristina Valls; M. Blanca Roncero

2014-01-01

An inter-laboratory comparison of a UV-Vis spectroscopic method (TAPPI T 282 om-13 “Hexeneuronic acid content of chemical pulp”) for hexeneuronic acid measurements was conducted using three eucalyptus kraft pulps. The pulp samples were produced in a laboratory at kappa numbers of approximately 14, 20, and 35. The hexeneuronic acid contents of the three pulps were...

Product Evaluation Laboratory

Data.gov (United States)

Federal Laboratory Consortium — This laboratory offers the services of highly trained and experienced specialists that have a full complement of measuring equipment. It is equipped with two optical...

The influence of uncertainties of measurements in laboratory performance evaluation by intercomparison program in radionuclide analyses of environmental samples

International Nuclear Information System (INIS)

Tauhata, L.; Vianna, M.E.; Oliveira, A.E. de; Clain, A.F.; Ferreira, A.C.M.; Bernardes, E.M.

2000-01-01

The accuracy and precision of results of the radionuclide analyses in environmental samples are widely claimed internationally due to its consequences in the decision process coupled to evaluation of environmental pollution, impact, internal and external population exposure. These characteristics of measurement of the laboratories can be shown clearly using intercomparison data, due to the existence of a reference value and the need of three determinations for each analysis. In intercomparison studies accuracy in radionuclide assays in low-level environmental samples has usually been the main focus in performance evaluation and it can be estimated by taking into account the deviation between the experimental laboratory mean value and the reference value. The laboratory repeatability of measurements or their standard deviation is seldom included in performance evaluation. In order to show the influence of the uncertainties in performance evaluation of the laboratories, data of 22 intercomparison runs which distributed 790 spiked environmental samples to 20 Brazilian participant laboratories were compared, using the 'Normalised Standard Deviation' as statistical criteria for performance evaluation of U.S.EPA. It mainly takes into account the laboratory accuracy and the performance evaluation using the same data classified by normalised standard deviation modified by a weight reactor that includes the individual laboratory uncertainty. The results show a relative decrease in laboratory performance in each radionuclide assay: 1.8% for 65 Zn, 2.8% for 40 K, 3.4 for 60 Co, 3.7% for 134 Cs, 4.0% for 137 Cs, 4.4% for Th and U nat , 4.5% for 3 H, 6.3% for 133 Ba, 8.6% for 90 Sr, 10.6% for Gross Alpha, 10.9% for 106 Ru, 11.1% for 226 Ra, 11.5% for Gross Beta and 13.6% for 228 Ra. The changes in the parameters of the statistical distribution function were negligible and the distribution remained as Gaussian type for all radionuclides analysed. Data analyses in terms of

Comparison of Laboratory and Field Remote Sensing Methods to Measure Forage Quality

OpenAIRE

Guo, Xulin; Wilmshurst, John F.; Li, Zhaoqin

2010-01-01

Recent research in range ecology has emphasized the importance of forage quality as a key indicator of rangeland condition. However, we lack tools to evaluate forage quality at scales appropriate for management. Using canopy reflectance data to measure forage quality has been conducted at both laboratory and field levels separately, but little work has been conducted to evaluate these methods simultaneously. The objective of this study is to find a reliable way of assessing grassland quality ...

Sensor set-up for wireless measurement of automotive rim and wheel parameters in laboratory conditions

Science.gov (United States)

Borecki, M.; Prus, P.; Korwin-Pawlowski, M. L.; Rychlik, A.; Kozubel, W.

2017-08-01

Modern rims and wheels are tested at the design and production stages. Tests can be performed in laboratory conditions and on the ride. In the laboratory, complex and costly equipment is used, as for example wheel balancers and impact testers. Modern wheel balancers are equipped with electronic and electro-mechanical units that enable touch-less measurement of dimensions, including precision measurement of radial and lateral wheel run-out, automatic positioning and application of the counterweights, and vehicle wheel set monitoring - tread wear, drift angles and run-out unbalance. Those tests are performed by on-wheel axis measurements with laser distance meters. The impact tester enables dropping of weights from a defined height onto a wheel. Test criteria are the loss of pressure of the tire and generation of cracks in the wheel without direct impact of the falling weights. In the present paper, a set up composed of three accelerometers, a temperature sensor and a pressure sensor is examined as the base of a wheel tester. The sensor set-up configuration, on-line diagnostic and signal transmission are discussed.

High-resolution VUV spectra of carbon, neon and argon in a wavelength range of 250 to 2300 A for plasma diagnostics observed with a 3 m normal incidence spectrometer in LHD

International Nuclear Information System (INIS)

Katai, Ryuji; Morita, Shigeru; Goto, Motoshi

2007-01-01

Intrinsic impurities have been much reduced in toroidal fusion devices through the development of several wall-conditioning techniques as well as by the use of carbon materials in the first wall and divertor plates. Impurity elements useful for passive plasma spectroscopy have been then extremely limited. At present, only carbon is a subject for spectroscopic diagnostics in most discharges except for fuel atoms. The use of rare gas as a brighter light source is a method to overcome the present difficulty in passive spectroscopy. Recently, rare gases have also been used for edge cooling to reduce the divertor heat flux. Therefore, high-resolution spectra (Δλ - 0.2 A) from neon and argon in a 250 to 2300 A wavelength range have been measured using a 3 m normal incidence spectrometer in Large Helical Device (LHD) and the measured spectra were precisely analyzed. The VUV spectra of carbon, neon and argon are presented for spectroscopic use and their wavelengths are tabulated with their relative intensities. The spectral profiles of almost all the spectral lines measured here are formed by the Doppler broadening and self-absorption processes. The Doppler broadening of neon and argon spectra are plotted against the ionization energies and Doppler spectra from carbon lines are presented. The self-absorption spectra of the hydrogen Lyman-α line, which are found in the LHD high-density discharge, are also presented and the neutral density is analytically estimated. (author)

Measurements of Schottky barrier at the low-k SiOC:H/Cu interface using vacuum ultraviolet photoemission spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Guo, X.; Pei, D.; Zheng, H.; Shohet, J. L. [Plasma Processing and Technology Laboratory and Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); King, S. W. [Logic Technology Development, Intel Corporation, Hillsboro, Oregon 97124 (United States); Lin, Y.-H.; Fung, H.-S.; Chen, C.-C. [National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan (China); Nishi, Y. [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States)

2015-12-07

The band alignment between copper interconnects and their low-k interlayer dielectrics is critical to understanding the fundamental mechanisms involved in electrical leakage in low-k/Cu interconnects. In this work, vacuum-ultraviolet (VUV) photoemission spectroscopy is utilized to determine the potential of the Schottky barrier present at low-k a-SiOC:H/Cu interfaces. By examining the photoemission spectra before and after VUV exposure of a low-k a-SiOC:H (k = 3.3) thin film fabricated by plasma-enhanced chemical-vapor deposition on a polished Cu substrate, it was found that photons with energies of 4.9 eV or greater can deplete accumulated charge in a-SiOC:H films, while VUV photons with energies of 4.7 eV or less, did not have this effect. These critical values were identified to relate the electric potential of the interface barrier between the a-SiOC:H and the Cu layers. Using this method, the Schottky barrier at the low-k a-SiOC:H (k = 3.3)/Cu interface was determined to be 4.8 ± 0.1 eV.

Quality assurance in the measurement of internal radioactive contamination and dose assessment and the United States Department of Energy Laboratory Accreditation Program

International Nuclear Information System (INIS)

Bhatt, Anita

2016-01-01

The Quality Assurance for analytical measurement of internal radioactive contamination and dose assessment in the United States (US) is achieved through the US Department of Energy (DOE) Laboratory Accreditation Program (DOELAP) for both Dosimetry and Radio bioassay laboratories for approximately 150,000 radiation workers. This presentation will explain the link between Quality Assurance and the DOELAP Accreditation process. DOELAP is a DOE complex-wide safety program that ensures the quality of worker radiation protection programs. DOELAP tests the ability of laboratories to accurately measure and quantify radiation dose to workers and assures the laboratories quality systems are capable of defending and sustaining their measurement results. The United States Law in Title 10 of the Code of Federal Regulations 835 requires that personnel Dosimetry and Radio bioassay programs be tested and accredited

Inter-Laboratory Comparison for Calibration of Relative Humidity Devices Among Accredited Laboratories in Malaysia

Science.gov (United States)

Hussain, F.; Khairuddin, S.; Othman, H.

2017-01-01

An inter-laboratory comparison in relative humidity measurements among accredited laboratories has been coordinated by the National Metrology Institute of Malaysia. It was carried out to determine the performance of the participating laboratories. The objective of the comparison was to acknowledge the participating laboratories competencies and to verify the level of accuracies declared in their scope of accreditation, in accordance with the MS ISO/IEC 17025 accreditation. The measurement parameter involved was relative humidity for the range of 30-90 %rh at a nominal temperature of 50°C. Eight accredited laboratories participated in the inter-laboratory comparison. Two units of artifacts have been circulated among the participants as the transfer standards.

The implementation of the Wendelstein 7-X control a data acquisition concepts at VUV/XUV overview spectrometers HEXOS

International Nuclear Information System (INIS)

Schacht, Jörg; Pingel, Steffen; Herbst, Uwe; Hennig, Christine; Burhenn, Rainer; Hollfeld, Klaus-Peter; Jordan, Frank

2013-01-01

Highlights: ► Shown in this paper is the implementation of the W7-X CoDaC concept for the HEXOS diagnostic. ► It explains the field, process and supervision level. ► The paper contains descriptions of the slow and fast control and data acquisition stations. ► It introduces the diagnosticians view to CoDaC via high level concept. -- Abstract: HEXOS (high efficiency extreme ultraviolet overview spectrometer) is an optimized set of four efficient VUV/XUV spectrometers. It is suitable for a complete coverage of the wavelength range of interest with sufficient spectral resolution. The spectrometers cover the entire wavelength range of 2.5–160 nm with high performance (up to 9999 spectra at spectra rate of 1000 s −1 ). To operate according to the Wendelstein 7-X (W7-X) control and data acquisition guidelines all necessary concepts for safety, autonomous and subordinated operation, and segment program controlled experiment operation will be implemented at HEXOS. The design of the HEXOS control and data acquisition system and the implementation of the main W7-X control and data acquisition concepts are described. An outlook on the test phase at the TEXTOR (Tokamak Experiment for Technology Oriented Research) device and the commissioning phase at W7-X is given

ADVANTAGES AND DISADVANTAGES OF MODERN LABORATORY MEASUREMENT OF THE COEFFICIENT OF PERMEABILITY FOR SOIL MATERIALS

OpenAIRE

Veinović, Želimir; Kovačević-Zelić, Biljana; Kvasnička, Predrag

2003-01-01

Permeability tests are one of the most often performed experiments in geotechnics. Conventional methods conducted by oedometer and triaxial apparatus have many disadvantages, the most significant being the test duration. As a consequence, errors in permeability measurements could occur. On the contrary, by applying modern flow-pump method, permeability measurements can be obtained much more rapidly. Moreover, the permeability/void ratio relation can be obtained by using adequate laboratory de...

NEW APPROACHES: Measurement of the mean lifetime of cosmic ray muons in the A-level laboratory

Science.gov (United States)

Dunne, Peter; Costich, David; O'Sullivan, Sean

1998-09-01

The Turning Points in Physics module from the NEAB A-level Modular Physics syllabus requires students to have an understanding of relativistic time dilation and offers the measurement of the mean lifetime of cosmic ray muons as an example of supporting experimental evidence. This article describes a direct measurement of muon lifetime carried out in the A-level laboratory.

Fully automated laboratory and field-portable goniometer used for performing accurate and precise multiangular reflectance measurements

Science.gov (United States)

Harms, Justin D.; Bachmann, Charles M.; Ambeau, Brittany L.; Faulring, Jason W.; Ruiz Torres, Andres J.; Badura, Gregory; Myers, Emily

2017-10-01

Field-portable goniometers are created for a wide variety of applications. Many of these applications require specific types of instruments and measurement schemes and must operate in challenging environments. Therefore, designs are based on the requirements that are specific to the application. We present a field-portable goniometer that was designed for measuring the hemispherical-conical reflectance factor (HCRF) of various soils and low-growing vegetation in austere coastal and desert environments and biconical reflectance factors in laboratory settings. Unlike some goniometers, this system features a requirement for "target-plane tracking" to ensure that measurements can be collected on sloped surfaces, without compromising angular accuracy. The system also features a second upward-looking spectrometer to measure the spatially dependent incoming illumination, an integrated software package to provide full automation, an automated leveling system to ensure a standard frame of reference, a design that minimizes the obscuration due to self-shading to measure the opposition effect, and the ability to record a digital elevation model of the target region. This fully automated and highly mobile system obtains accurate and precise measurements of HCRF in a wide variety of terrain and in less time than most other systems while not sacrificing consistency or repeatability in laboratory environments.

Photoluminescence of Eu2+-doped CaMgSi2xO6+2x (1.00≤x≤1.20) phosphors in UV-VUV region

International Nuclear Information System (INIS)

Zhang Zhiya; Wang Yuhua

2008-01-01

Alkaline-earth silicate phosphors CaMgSi 2x O 6+2x :Eu 2+ (1.00≤x≤1.20) were prepared by traditional solid-state reaction. The phosphors showed an intense blue emission centered around 453 nm, with both 254 and 147 nm excitations. The host absorption below 200 nm in the excitation spectra consisted of two bands around 160 and 190 nm. The band around 160 nm was ascertained to be associated with the SiO 4 -tetrahedra and MgO 6 -polyhedra, and that around 190 nm was due to the CaO 8 -polyhedra or some impurities. The incorporation of excess Si of less than 15% would not lead to formation of impurities and the results indicated that an appropriate Si excess could improve the Photoluminescence (PL) intensity in both ultraviolet (UV) and vacuum ultraviolet (VUV) regions

Collection of measurement data in 2013 fiscal year at the Horonobe Underground Research Laboratory project

International Nuclear Information System (INIS)

Aoyagi, Kazuhei; Kawate, Satoshi

2015-12-01

The Horonobe Underground Research Laboratory (URL) Project has being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host sedimentary formations at Horonobe, northern Hokkaido. The URL project consists of two major research areas, “Geoscientific Research” and “R and D on Geological Disposal Technologies”, and proceeds in three overlapping phases, “Phase I: Surface-based investigations”, “Phase II: Investigations during tunnel excavation” and “Phase III: Investigations in the underground facilities”, over a period of around 20 years. The Phase I geoscientific research was carried out from March 2001 to March 2006 in parallel with design and execution scheme on URL facilities. In addition, identifying key issues that need to be addressed in the Phase II/III investigations were planned. At the beginning of the Phase II investigations, an investigation report titled “Measurement Plan and Observational Construction Program on Shaft Excavation at the Horonobe Underground Research Laboratory Project” (hereinafter referred to as “Observational Construction Programs”) and an investigation report titled “Measurement Plan and Observational Construction Program on Drift Excavation at the Horonobe Underground Research Laboratory Project” were published. The Observational Construction Program summarizes the followings from the results of the Phase I investigations: measurements for safety and reasonable constructions, enhancement of shaft design and construction technologies and evaluation of appropriateness for the deep geological environment model estimated before shaft excavation. This report summarizes the measurements data acquired at the Ventilation Shaft, the West Shaft and the drifts in 2013 fiscal year for the purpose of the basic data for carrying out the Observational Construction Program. A DVD-ROM is

Application of the MGAU code for measuring 235U enrichment at the Brazilian Safeguards Laboratory

International Nuclear Information System (INIS)

Grund, Marcos S.; Dias, Fabio C.

2009-01-01

MGAU is a software tool for conducting uranium enrichment measurements based on high-resolution gamma ray spectroscopy. The code is capable of analyzing spectra (90 - 120 KeV region) collected from a wide variety of sample geometries and compositions. The main advantage of the code is its ability to perform spectra evaluation without a requirement for calibration with representative standards. However, it does require that the daughter isotopes be in activity equilibrium with the 235 U and 238 U parent isotopes. In order for the code to be more versatile in overcoming its limitations, a modified version of the traditional 'enrichment meter' method has been also added. In order to perform confirmatory uranium enrichment measurements for safeguards purposes at a laboratory environment, the Brazilian Safeguards Laboratory is investigating the performance of a nondestructive technique based on the use of the MGAU code for analyzing of gamma-ray spectra collected from pure uranium samples (primarily natural and low enriched powders and pellets). Several new good practice procedures were implemented in order to optimize the performance of the method at the best achievable level. This includes positioning of both the high-purity germanium detector and the sample inside a lead chamber for reducing background influence, collection of replicate measurements, and application of robust statistical treatment of data to reduce random contributions from counting statistics to the final uncertainty. Also, temperature and humidity inside the laboratory were monitored so that significant influences in results could be observed. Based on the results arising from analysis of certified reference materials, this paper discusses the performance of the MGAU code version 4.0 with focus on the uncertainties related to sample-dependent effects (mass, density, matrix composition and enrichment level). The reliability of the MGAU predicted uncertainty for single measurements and the occurrence

Science laboratory behavior strategies of students relative to performance in and attitude to laboratory work

Science.gov (United States)

Okebukola, Peter Akinsola

The relationship between science laboratory behavior strategies of students and performance in and attitude to laboratory work was investigated in an observational study of 160 laboratory sessions involving 600 class five (eleventh grade) biology students. Zero-order correlations between the behavior strategies and outcome measures reveal a set of low to strong relationships. Transmitting information, listening and nonlesson related behaviors exhibited low correlations with practical skills and the attitude measure. The correlations between manipulating apparatus and observation with practical skills measures were found to be strong. Multiple correlation analysis revealed that the behaviors of students in the laboratories observed accounted for a large percentage of the variance in the scores on manipulative skills and a low percentage on interpretation of data, responsibility, initiative, and work habits. One significant canonical correlation emerged. The loadings on this canonical variate indicate that the practical skills measures, i.e., planning and design, manipulative skills and conduct of experiments, observation and recording of data, and attitude to laboratory work made primary contributions to the canonical relationship. Suggestions as to how students can be encouraged to go beyond cookbook-like laboratories and develop a more favorable attitude to laboratory work are made.

Collection of URL measurement data in 2006 at the Horonobe Underground Research Laboratory project

International Nuclear Information System (INIS)

Kumagai, Yasuhito; Funaki, Hironori; Yamasaki, Masanao; Yamaguchi, Takehiro; Sanada, Hiroyuki; Abe, Hironobu; Orukawa, Go

2008-07-01

The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host sedimentary formations at Horonobe, northern Hokkaido. The project consists two major research area, Geoscientific Research' and 'R and D on Geological Disposal', and proceeds in three overlapping phases, 'Phase I: Surface-based investigation', 'Phase II: Construction' and 'Phase III: Operation', over a period of 20 years. The Phase I geoscientific research was carried out from March 2001 to March 2005 in parallel with design and execution scheme on URL facilities. In addition, identifying key issues that need to be addressed in the Phase II/III investigations was carried out. At the inception of the Phase II investigations, an investigation report titled 'Measurement Plan and Observational Construction Program on Shaft Excavation at the Horonobe Underground Research Laboratory Project' (hereinafter referred to as Observational Construction Program') was published. The Observational Construction Program summarizes followings lessons learnt from the Phase I investigations: measurements for safety/reasonable construction, measurements for R and D on enhancement of shaft design/construction technology, and measurements for verification of the deep geological environment estimated before shaft excavation. This report summarizes the measurements data acquired at the Ventilation Shaft (to approx. 50m depth) and the East Shaft (to approx. 40m depth) in 2006 based on the Observational Construction Program. CD-ROM and DVD-ROM are attached as an appendix. (J.P.N.)

Handbook of laboratory health and safety measures

International Nuclear Information System (INIS)

Pal, S.B.

1985-01-01

Eighteen chapters deal with all kinds of possible health and safety hazards, chemical, physical and biological, arising in laboratories. Two chapters, on X-ray hazards - diagnostic and therapeutic, and radiation protection in radionuclide investigations, respectively are indexed separately. (U.K.)

Quality improvement project in cervical cancer screening: practical measures for monitoring laboratory performance.

Science.gov (United States)

Tarkkanen, Jussi; Geagea, Antoine; Nieminen, Pekka; Anttila, Ahti

2003-01-01

We conducted a quality improvement project in a cervical cancer screening programme in Helsinki in order to see if detection of precancerous lesions could be influenced by external (participation rate) and internal (laboratory praxis) quality measures. In order to increase the participation rate, a second personal invitation to Pap-test was mailed to nonparticipants of the first call. In order to improve the quality of screening, the cytotechnicians monitored their performance longitudinally by recording the number of slides reviewed per day, the pick-up rate of abnormal smears, the report of the consulting cytopathologist, and the number of histologically verified lesions detected from the cases that they had screened. Regular sessions were held to compare the histological findings with the cytological findings of all cases referred for colposcopy. No pressure was applied on the cytotechnicians to ensure that they felt comfortable with their daily workload. A total of 110 000 smears were screened for cervical cancer at the Helsinki City Hospital during 1996-99. Initially, the overall participation rate increased from 62% to 71%. The number of histologically confirmed precancerous lesions (CIN 1-3) more than doubled and their detection rate increased from 0.32% to 0.72%. Continuous education and feedback from daily work performance were important, yet rather inexpensive means in increasing laboratory performance. Additional measures are needed to further increase the participation rate. Impact of the quality measures on cancer incidence needs to be assessed later on.

REFLECTANCE ANISOTROPY MEASUREMENTS USING A PUSHBROOM SPECTROMETER MOUNTED ON UAV AND A LABORATORY GONIOMETER – PRELIMINARY RESULTS

Directory of Open Access Journals (Sweden)

J. Suomalainen

2015-08-01

Full Text Available During 2014–2015 we have developed a new method to measure reflectance factor anisotropy using a pushbroom spectrometer mounted on a multicopter UAV. In this paper/presentation we describe the acquisition method and show the preliminary results of the experiment. To validate the measurements the same targets have also been measured with a laboratory goniometer system. The first experiments over sugar beet fields in 2014 show similar trends in both UAV and laboratory anisotropy data, but also some differences caused by differences in sampling and diffuse illumination. In 2015 a more extensive study on wheat, barley and potato fields were performed. The measurements were repeated on three days over the growth of the crops allowing linking the development of the crops to the anisotropy signals. On each day the anisotropy measurement was repeated 4–5 times with different solar zenith angles ranging from 60° to 40° allowing analysis how the solar angle affects the anisotropy. The first results of these experiments will be presented in this conference.

Mounted Smartphones as Measurement and Control Platforms for Motor-Based Laboratory Test-Beds

OpenAIRE

Jared A. Frank; Anthony Brill; Vikram Kapila

2016-01-01

Laboratory education in science and engineering often entails the use of test-beds equipped with costly peripherals for sensing, acquisition, storage, processing, and control of physical behavior. However, costly peripherals are no longer necessary to obtain precise measurements and achieve stable feedback control of test-beds. With smartphones performing diverse sensing and processing tasks, this study examines the feasibility of mounting smartphones directly to test-beds to exploit their em...

Laboratory quality assurance and its role in the safeguards analytical laboratory evaluation (SALE) program

International Nuclear Information System (INIS)

Delvin, W.L.; Pietri, C.E.

1981-07-01

Since the late 1960's, strong emphasis has been given to quality assurance in the nuclear industry, particularly to that part involved in nuclear reactors. This emphasis has had impact on the analytical chemistry laboratory because of the importance of analytical measurements in the certification and acceptance of materials used in the fabrication and construction of reactor components. Laboratory quality assurance, in which the principles of quality assurance are applied to laboratory operations, has a significant role to play in processing, fabrication, and construction programs of the nuclear industry. That role impacts not only process control and material certification, but also safeguards and nuclear materials accountability. The implementation of laboratory quality assurance is done through a program plan that specifies how the principles of quality assurance are to be applied. Laboratory quality assurance identifies weaknesses and deficiencies in laboratory operations and provides confidence in the reliability of laboratory results. Such confidence in laboratory measurements is essential to the proper evaluation of laboratories participating in the Safeguards Analytical Laboratory Evaluation (SALE) Program

Characteristics of radon concentration distributions measurement with two-filter method in the storage rooms of Ra-Be neutron source and the adjacent laboratories

International Nuclear Information System (INIS)

Liu Shuhuan; Chu Jun; Zhao Yaolin; Bao Lihong; Chen Wei; Wu Yuelei

2012-01-01

The basic principle of radon measurement with two-filter method is introduced in this paper. The levels of radon concentration in the storage rooms and the adjacent laboratories are measured and compared with the type of FT-648 radon measurement instrument. The measurement results showed that the levels of radon concentration in Ra-Be neutron source storage rooms are not higher than those in the adjacent laboratories, then it can be deduced that no radon gas was leaked out form the shielded and sealed Ra-Be neutron sources. The radon concentrations measured in the laboratories were near to the average level compared to the statistical results of the indoor dwellings' radon concentrations in Xi'an. The values didn't exceed the national standard limits(200 Bq·m -3 ). Furthermore, it is found that the radon concentration value measured at rainy or cloudy day is lesser than that at sunny day, and good ventilation conditions can effectively decrease the indoor radon concentration level. Meanwhile, the mechanisms of the radon concentration distributions in the laboratories influenced by the factors including various weather conditions (rainy, sunny and cloudy), ventilation and different measurement time periods in a day, etc. are primarily analyzed. The measurement results in this work provide some relative reference data for prediction the situations of Ra-Be neutron sources safety storage and experimenters' radiation protection in the laboratories. (authors)

Collection of URL measurement data in 2010 fiscal year at the Horonobe Underground Research Laboratory project

International Nuclear Information System (INIS)

Inagaki, Daisuke; Sawada, Sumiyuki; Tokiwa, Tetsuya; Tsusaka, Kimikazu; Amano, Yuki; Niinuma, Hiroaki

2012-09-01

The Horonobe Underground Research Laboratory (URL) Project has being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host sedimentary formations at Horonobe, northern Hokkaido. The URL project consists of two major research areas, 'Geoscientific Research' and 'R and D on Geological Disposal Technologies', and proceeds in three overlapping phases, 'Phase I: Surface-based investigations', 'Phase II: Investigations during tunnel excavation' and 'Phase III: Investigations in the underground facilities', over a period of around 20 years. The Phase I geoscientific research was carried out from March 2001 to March 2006 in parallel with design and execution scheme on URL facilities. In addition, identifying key issues that need to be addressed in the Phase II/III investigations was planned. At the begining of the Phase II investigations, an investigation report titled 'Measurement Plan and Observational Construction Program on Shaft Excavation at the Horonobe Underground Research Laboratory Project' (hereinafter referred to as 'Observational Construction Program') and an investigation report titled 'Measurement Plan and Observational Construction Program on Drift Excavation at the Horonobe Underground Research Laboratory Project' were published. The Observational Construction Program summarizes the followings from the results of the Phase I investigations: measurements for safety and reasonable constructions, enhancement of shaft design and construction technologies and evaluation of appropriateness for the deep geological environment model estimated before shaft excavation. This report summarizes the measurements data acquired at the Ventilation Shaft, the East Shaft and the drifts in 2010 fiscal year based on the Observational Construction Program. The report summarizes the measurements data for the purpose of acquisition the basic data for

Collection of URL measurement data in 2011 fiscal year at the Horonobe Underground Research Laboratory project

International Nuclear Information System (INIS)

Inagaki, Daisuke; Tokiwa, Tetsuya; Murakami, Hiroaki

2013-02-01

The Horonobe Underground Research Laboratory (URL) Project has being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host sedimentary formations at Horonobe, northern Hokkaido. The URL project consists of two major research areas, 'Geoscientific Research' and 'R and D on Geological Disposal Technologies', and proceeds in three overlapping phases, 'Phase I: Surface-based investigations', 'Phase II: Investigations during tunnel excavation' and 'Phase III: Investigations in the underground facilities', over a period of around 20 years. The Phase I geoscientific research was carried out from March 2001 to March 2006 in parallel with design and execution scheme on URL facilities. In addition, identifying key issues that need to be addressed in the Phase II/III investigations was planned. At the beginning of the Phase II investigations, an investigation report titled 'Measurement Plan and Observational Construction Program on Shaft Excavation at the Horonobe Underground Research Laboratory Project' (hereinafter referred to as 'Observational Construction Program') and an investigation report titled 'Measurement Plan and Observational Construction Program on Drift Excavation at the Horonobe Underground Research Laboratory Project' were published. The Observational Construction Program summarizes the followings from the results of the Phase I investigations: measurements for safety and reasonable constructions, enhancement of shaft design and construction technologies and evaluation of appropriateness for the deep geological environment model estimated before shaft excavation. This report summarizes the measurements data acquired at the Ventilation Shaft, the East Shaft and the drifts in 2011 fiscal year based on the Observational Construction Program. The report summarizes the measurements data for the purpose of acquisition the basic data for

Acoustics. Measurement of sound insulation in buildings and of building elements. Laboratory measurements of the reduction of transmitted impact noise by floor coverings on a heavyweight standard floor

CERN Document Server

British Standards Institution. London

1998-01-01

Acoustics. Measurement of sound insulation in buildings and of building elements. Laboratory measurements of the reduction of transmitted impact noise by floor coverings on a heavyweight standard floor

The application of acoustic emission measurements on laboratory testpieces to large scale pressure vessel monitoring

International Nuclear Information System (INIS)

Ingham, T.; Dawson, D.G.

1975-01-01

A test pressure vessel containing 4 artificial defects was monitored for emission whilst pressure cycling to failure. Testpieces cut from both the failed vessel and from as-rolled plate material were tested in the laboratory. A marked difference in emission characteristics was observed between plate and vessel testpieces. Activity from vessel material was virtually constant after general yield and emission amplitudes were low. Plate testpieces showed maximum activity at general yield and more frequent high amplitude emissions. An attempt has been made to compare the system sensitivities between the pressure vessel test and laboratory tests. In the absence of an absolute calibration device, system sensitivities were estimated using dummy signals generated by the excitation of an emission sensor. The measurements have shown an overall difference in sensitivity between vessel and laboratory tests of approximately 25db. The reduced sensitivity in the vessel test is attributed to a combination of differences in sensors, acoustic couplant, attenuation, and dispersion relative to laboratory tests and the relative significance of these factors is discussed. Signal amplitude analysis of the emissions monitored from laboratory testpieces showed that, whith losses of the order of 25 to 30db, few emissions would be detected from the pressure vessel test. It is concluded that no reliable prediction of acoustic behaviour of a structure may be made from laboratory test unless testpieces of the actual structural material are used. A considerable improvement in detection sensitivity, is also required for reliable detection of defects in low strength ductile materials and an absolute method of system calibration is required between tests

Safety in laboratories: Indian scenario.

Science.gov (United States)

Mustafa, Ajaz; Farooq, A Jan; Qadri, Gj; S A, Tabish

2008-07-01

Health and safety in clinical laboratories is becoming an increasingly important subject as a result of emergence of highly infectious diseases such as Hepatitis and HIV. A cross sectional study was carried out to study the safety measures being adopted in clinical laboratories of India. Heads of laboratories of teaching hospitals of India were subjected to a standardized, pretested questionnaire. Response rate was 44.8%. only 60% of laboratories had person in-charge of safety in laboratory. Seventy three percent of laboratories had safety education program regarding hazards. In 91% of laboratories staff is using protective clothing while working in laboratories. Hazardous material regulations are followed in 78% of laboratories. Regular health check ups are carried among laboratory staff in 43.4% of laboratories.Safety manual is available in 56.5% of laboratories. 73.9% of laboratories are equipped with fire extinguishers. Fume cupboards are provided in 34.7% of laboratories and they are regularly checked in 87.5% of these laboratories. In 78.26% of laboratories suitable measures are taken to minimize formation of aerosols.In 95.6% of laboratories waste is disposed off as per bio-medical waste management handling rules. Laboratory of one private medical college was accredited with NABL and safety parameters were better in that laboratory. Installing safety engineered devices apparently contributes to significant decrease in injuries in laboratories; laboratory safety has to be a part of overall quality assurance programme in hospitals. Accreditation has to be made necessary for all laboratories.

Oceanic crustal velocities from laboratory and logging measurements of Integrated Ocean Drilling Program Hole 1256D

Science.gov (United States)

Gilbert, Lisa A.; Salisbury, Matthew H.

2011-09-01

Drilling and logging of Integrated Ocean Drilling Program (IODP) Hole 1256D have provided a unique opportunity for systematically studying a fundamental problem in marine geophysics: What influences the seismic structure of oceanic crust, porosity or composition? Compressional wave velocities (Vp) logged in open hole or from regional refraction measurements integrate both the host rock and cracks in the crust. To determine the influence of cracks on Vp at several scales, we first need an accurate ground truth in the form of laboratory Vp on crack-free, or nearly crack-free samples. We measured Vp on 46 water-saturated samples at in situ pressures to determine the baseline velocities of the host rock. These new results match or exceed Vp logs throughout most of the hole, especially in the lower dikes and gabbros, where porosities are low. In contrast, samples measured at sea under ambient laboratory conditions, had consistently lower Vp than the Vp logs, even after correction to in situ pressures. Crack-free Vp calculated from simple models of logging and laboratory porosity data for different lithologies and facies suggest that crustal velocities in the lavas and upper dikes are controlled by porosity. In particular, the models demonstrate significant large-scale porosity in the lavas, especially in the sections identified as fractured flows and breccias. However, crustal velocities in the lower dikes and gabbros are increasingly controlled by petrology as the layer 2-3 boundary is approached.

Computer Network Availability at Sandia National Laboratories, Albuquerque NM: Measurement and Perception; TOPICAL

International Nuclear Information System (INIS)

NELSON, SPENCER D.; TOLENDINO, LAWRENCE F.

1999-01-01

The desire to provide a measure of computer network availability at Sandia National Laboratories has existed for along time. Several attempts were made to build this measure by accurately recording network failures, identifying the type of network element involved, the root cause of the problem, and the time to repair the fault. Recognizing the limitations of available methods, it became obvious that another approach of determining network availability had to be defined. The chosen concept involved the periodic sampling of network services and applications from various network locations. A measure of ''network'' availability was then calculated based on the ratio of polling success to failure. The effort required to gather the information and produce a useful metric is not prohibitive and the information gained has verified long held feelings regarding network performance with real data

Storage ring development at the National Synchrotron Light Source

International Nuclear Information System (INIS)

Krinsky, S.; Bittner, J.; Fauchet, A.M.; Johnson, E.D.; Keane, J.; Murphy, J.; Nawrocky, R.J.; Rogers, J.; Singh, O.V.; Yu, L.H.

1991-09-01

This report contains papers on the following topics: Transverse Beam Profile Monitor; Bunch Length Measurements in the VUV Storage Ring; Photoelectric Effect Photon Beam Position Monitors; RF Receivers for Processing Electron Beam Pick-up Electrode Signals; Real-Time Global Orbit Feedback Systems; Local Orbit Feedback; Active Interlock System for High Power Insertion Devices in the X-ray Ring; Bunch Lengthening Cavity for the VUV Ring; SXLS Storage Ring Design

Microgravity Emissions Laboratory (MEL)

Data.gov (United States)

Federal Laboratory Consortium — The Microgravity Emissions Laboratory (MEL) utilizes a low-frequency acceleration measurement system for the characterization of rigid body inertial forces generated...

Contact Thermocouple Methodology and Evaluation for Temperature Measurement in the Laboratory

Science.gov (United States)

Brewer, Ethan J.; Pawlik, Ralph J.; Krause, David L.

2013-01-01

Laboratory testing of advanced aerospace components very often requires highly accurate temperature measurement and control devices, as well as methods to precisely analyze and predict the performance of such components. Analysis of test articles depends on accurate measurements of temperature across the specimen. Where possible, this task is accomplished using many thermocouples welded directly to the test specimen, which can produce results with great precision. However, it is known that thermocouple spot welds can initiate deleterious cracks in some materials, prohibiting the use of welded thermocouples. Such is the case for the nickel-based superalloy MarM-247, which is used in the high temperature, high pressure heater heads for the Advanced Stirling Converter component of the Advanced Stirling Radioisotope Generator space power system. To overcome this limitation, a method was developed that uses small diameter contact thermocouples to measure the temperature of heater head test articles with the same level of accuracy as welded thermocouples. This paper includes a brief introduction and a background describing the circumstances that compelled the development of the contact thermocouple measurement method. Next, the paper describes studies performed on contact thermocouple readings to determine the accuracy of results. It continues on to describe in detail the developed measurement method and the evaluation of results produced. A further study that evaluates the performance of different measurement output devices is also described. Finally, a brief conclusion and summary of results is provided.

Undergraduate Laboratory Experiment: Measuring Matter Antimatter Asymmetries at the Large Hadron Collider

CERN Document Server

Parkes, Chris; Gutierrez, J

2015-01-01

This document is the student manual for a third year undergraduate laboratory experiment at the University of Manchester. This project aims to measure a fundamental difference between the behaviour of matter and antimatter through the analysis of data collected by the LHCb experiment at the Large Hadron Collider. The three-body dmecays $B^\\pm \\rightarrow h^\\pm h^+ h^-$, where $h^\\pm$ is a $\\pi^\\pm$ or $K^\\pm$ are studied. The inclusive matter antimatter asymmetry is calculated, and larger asymmetries are searched for in localized regions of the phase-space.

CRCPD`S laboratory accrediation program

Energy Technology Data Exchange (ETDEWEB)

Dukes, P.M. [South Carolina Department of Health and Environmental Control, Columbia, SC (United States)

1993-12-31

The Conference of Radiation Control Program Directors, or CRCPD, first became involved in a calibration laboratory accreditation program about 17 years ago. Since that time, the CRCPD has formed a Committee on Ionizing Measurements which writes criteria for the accreditation of laboratories, and performs the accreditation review process. To become accredited, a laboratory must agree to an administrative review, and an onsite review, and participate in measurement quality assurance (MQA) testing with the National Institute of Standards and Technology (NIST). The CRCPD currently has four accredited laboratories. All the laboratories are working with the Conference in promoting the improvement of MQA in radiation control programs.

Laboratory Measurement of the Brighter-fatter Effect in an H2RG Infrared Detector

Science.gov (United States)

Plazas, A. A.; Shapiro, C.; Smith, R.; Huff, E.; Rhodes, J.

2018-06-01

The “brighter-fatter” (BF) effect is a phenomenon—originally discovered in charge coupled devices—in which the size of the detector point-spread function (PSF) increases with brightness. We present, for the first time, laboratory measurements demonstrating the existence of the effect in a Hawaii-2RG HgCdTe near-infrared (NIR) detector. We use JPL’s Precision Projector Laboratory, a facility for emulating astronomical observations with UV/VIS/NIR detectors, to project about 17,000 point sources onto the detector to stimulate the effect. After calibrating the detector for nonlinearity with flat-fields, we find evidence that charge is nonlinearly shifted from bright pixels to neighboring pixels during exposures of point sources, consistent with the existence of a BF-type effect. NASAs Wide Field Infrared Survey Telescope (WFIRST) will use similar detectors to measure weak gravitational lensing from the shapes of hundreds of million of galaxies in the NIR. The WFIRST PSF size must be calibrated to ≈0.1% to avoid biased inferences of dark matter and dark energy parameters; therefore further study and calibration of the BF effect in realistic images will be crucial.

Compendium of the Environmental Measurements Laboratory's research projects related to the Chernobyl nuclear accident

Energy Technology Data Exchange (ETDEWEB)

Volchok, H L; Chieco, N [comps.

1986-10-01

Following the accident at the Chernobyl nuclear reactor power station in the USSR on April 26, 1986, the Environmental Measurements Laboratory (EML) initiated a number of research projects as follows: (1) selected sites in both the Deposition and Surface Air networks were alerted and their sampling protocols adjusted to accommodate the anticipated arrival times and activity concentrations of the Chernobyl debris; (2) a number of cooperative programs involving field work, sampling, analysis and data interpretation were set up with institutions and scientists in other countries; (3) EML's Regional Baseline Station at Chester, NJ, as well as the roof of the Laboratory in New York City, provided bases for sampling and measurements to study the radionuclide concentrations, radiation levels, physical characteristics and potential biological implications of the Chernobyl fallout on the northeastern United States; and (4) the resulting fallout from the Chernobyl accident provided an 'experiment of opportunity' in that it enabled us to study fresh fission product deposition using collection systems resurrected from the 1950's and 1960's for comparison with current state-of-the-art methodology. The 13 reports of this volume have been entered separately into the data base.

Toward a direct comparison of field and laboratory goniometer measurements

NARCIS (Netherlands)

Dangel, S.; Verstraete, M.; Schopfer, J.; Kneubuehler, M.; Schaepman, M.E.; Itten, K.I.

2005-01-01

Field and laboratory goniometers are widely used in the remote sensing community to assess spectrodirectional reflection properties of selected targets. Even when the same target and goniometer system are used, field and laboratory results cannot directly be compared due to inherent differences,

Vacuum ultra-violet damage and damage mitigation for plasma processing of highly porous organosilicate glass dielectrics

Energy Technology Data Exchange (ETDEWEB)

Marneffe, J.-F. de, E-mail: marneffe@imec.be; Lukaszewicz, M.; Porter, S. B.; Vajda, F.; Rutigliani, V.; Verdonck, P.; Baklanov, M. R. [IMEC v.z.w., 3001 Leuven (Belgium); Zhang, L.; Heyne, M.; El Otell, Z.; Krishtab, M. [IMEC v.z.w., 3001 Leuven (Belgium); Department of Chemistry, KULeuven, 3001 Leuven (Belgium); Goodyear, A.; Cooke, M. [Oxford Instruments Plasma Technology, BS49 4AP Bristol (United Kingdom)

2015-10-07

Porous organosilicate glass thin films, with k-value 2.0, were exposed to 147 nm vacuum ultra-violet (VUV) photons emitted in a Xenon capacitive coupled plasma discharge. Strong methyl bond depletion was observed, concomitant with a significant increase of the bulk dielectric constant. This indicates that, besides reactive radical diffusion, photons emitted during plasma processing do impede dielectric properties and therefore need to be tackled appropriately during patterning and integration. The detrimental effect of VUV irradiation can be partly suppressed by stuffing the low-k porous matrix with proper sacrificial polymers showing high VUV absorption together with good thermal and VUV stability. In addition, the choice of an appropriate hard-mask, showing high VUV absorption, can minimize VUV damage. Particular processing conditions allow to minimize the fluence of photons to the substrate and lead to negligible VUV damage. For patterned structures, in order to reduce VUV damage in the bulk and on feature sidewalls, the combination of both pore stuffing/material densification and absorbing hard-mask is recommended, and/or the use of low VUV-emitting plasma discharge.

A simple laboratory experiment to measure the surface tension of a liquid in contact with air

International Nuclear Information System (INIS)

Riba, Jordi-Roger; Esteban, Bernat

2014-01-01

A simple and accurate laboratory experiment to measure the surface tension of liquids has been developed, which is well suited to teach the behaviour of liquids to first- or second-year students of physics, engineering or chemistry. The experimental setup requires relatively inexpensive equipment usually found in physics and chemistry laboratories, since it consists of a used or recycled burette, an analytical balance and a stereoscopic microscope or a micrometer. Experimental data and error analysis show that the surface tension of distilled water, 1-butanol and glycerol can be determined with accuracy better than 1.4%. (paper)

Implementing planetary protection measures on the Mars Science Laboratory.

Science.gov (United States)

Benardini, James N; La Duc, Myron T; Beaudet, Robert A; Koukol, Robert

2014-01-01

The Mars Science Laboratory (MSL), comprising a cruise stage; an aeroshell; an entry, descent, and landing system; and the radioisotope thermoelectric generator-powered Curiosity rover, made history with its unprecedented sky crane landing on Mars on August 6, 2012. The mission's primary science objective has been to explore the area surrounding Gale Crater and assess its habitability for past life. Because microbial contamination could profoundly impact the integrity of the mission and compliance with international treaty was required, planetary protection measures were implemented on MSL hardware to verify that bioburden levels complied with NASA regulations. By applying the proper antimicrobial countermeasures throughout all phases of assembly, the total bacterial endospore burden of MSL at the time of launch was kept to 2.78×10⁵ spores, well within the required specification of less than 5.0×10⁵ spores. The total spore burden of the exposed surfaces of the landed MSL hardware was 5.64×10⁴, well below the allowed limit of 3.0×10⁵ spores. At the time of launch, the MSL spacecraft was burdened with an average of 22 spores/m², which included both planned landed and planned impacted hardware. Here, we report the results of a campaign to implement and verify planetary protection measures on the MSL flight system.

On the possibility of measuring the Earth's gravitomagnetic force in a new laboratory experiment

International Nuclear Information System (INIS)

Iorio, Lorenzo

2003-01-01

In this letter we propose, in a preliminary way, a new Earth-based laboratory experiment aimed at the detection of the gravitomagnetic field of the Earth. It consists of the measurement of the difference between the circular frequencies of two rotators moving along identical circular paths, but in opposite directions, on a horizontal friction-free plane in a vacuum chamber placed at the South Pole. The accuracy to our knowledge of the Earth's rotation from VLBI and the possibility of measuring the rotators' periods over many revolutions should allow for the feasibility of the proposed experiment. (letter to the editor)

Bias from two analytical laboratories involved in a long-term air monitoring program measuring organic pollutants in the Arctic: a quality assurance/quality control assessment.

Science.gov (United States)

Su, Yushan; Hung, Hayley; Stern, Gary; Sverko, Ed; Lao, Randy; Barresi, Enzo; Rosenberg, Bruno; Fellin, Phil; Li, Henrik; Xiao, Hang

2011-11-01

Initiated in 1992, air monitoring of organic pollutants in the Canadian Arctic provided spatial and temporal trends in support of Canada's participation in the Stockholm Convention of Persistent Organic Pollutants. The specific analytical laboratory charged with this task was changed in 2002 while field sampling protocols remained unchanged. Three rounds of intensive comparison studies were conducted in 2004, 2005, and 2008 to assess data comparability between the two laboratories. Analysis was compared for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in standards, blind samples of mixed standards and extracts of real air samples. Good measurement accuracy was achieved for both laboratories when standards were analyzed. Variation of measurement accuracy over time was found for some OCPs and PCBs in standards on a random and non-systematic manner. Relatively low accuracy in analyzing blind samples was likely related to the process of sample purification. Inter-laboratory measurement differences for standards (<30%) and samples (<70%) were generally less than or comparable to those reported in a previous inter-laboratory study with 21 participating laboratories. Regression analysis showed inconsistent data comparability between the two laboratories during the initial stages of the study. These inter-laboratory differences can complicate abilities to discern long-term trends of pollutants in a given sampling site. It is advisable to maintain long-term measurements with minimal changes in sample analysis.

Investigating Student Perceptions of the Chemistry Laboratory and Their Approaches to Learning in the Laboratory

Science.gov (United States)

Berger, Spencer Granett

This dissertation explores student perceptions of the instructional chemistry laboratory and the approaches students take when learning in the laboratory environment. To measure student perceptions of the chemistry laboratory, a survey instrument was developed. 413 students responded to the survey during the Fall 2011 semester. Students' perception of the usefulness of the laboratory in helping them learn chemistry in high school was related to several factors regarding their experiences in high school chemistry. Students' perception of the usefulness of the laboratory in helping them learn chemistry in college was also measured. Reasons students provided for the usefulness of the laboratory were categorized. To characterize approaches to learning in the laboratory, students were interviewed midway through semester (N=18). The interviews were used to create a framework describing learning approaches that students use in the laboratory environment. Students were categorized into three levels: students who view the laboratory as a requirement, students who believe that the laboratory augments their understanding, and students who view the laboratory as an important part of science. These categories describe the types of strategies students used when conducting experiments. To further explore the relationship between students' perception of the laboratory and their approaches to learning, two case studies are described. These case studies involve interviews in the beginning and end of the semester. In the interviews, students reflect on what they have learned in the laboratory and describe their perceptions of the laboratory environment. In order to encourage students to adopt higher-level approaches to learning in the laboratory, a metacognitive intervention was created. The intervention involved supplementary questions that students would answer while completing laboratory experiments. The questions were designed to encourage students to think critically about the

Laboratory measurements of the x-ray line emission from neon-like Fe XVII

International Nuclear Information System (INIS)

Brown, G V; Beiersdorfer, P; Chen, H; Scofield, J; Boyce, K R; Kelley, R L; Kilbourne, C A; Porter, F S; Gu, M F; Kahn, S M; Szymkowiak, A E

2006-01-01

The authors have conducted a systematic study of the dominant x-ray line emission from Fe XVII. These studies include relative line intensities in the optically thin limit, intensities in the presence of radiation from satellite lines from lower charge states of iron, and the absolute excitation cross sections of some of the strongest lines. These measurements were conducted at the Lawrence Livermore National Laboratory electron beam ion trap facility using crystal spectrometers and a NASA-Goddard Space Flight Center microcalorimeter array

Use of Balance Calibration Certificate to Calculate the Errors of Indication and Measurement Uncertainty in Mass Determinations Performed in Medical Laboratories

Directory of Open Access Journals (Sweden)

Adriana VÂLCU

2011-09-01

Full Text Available Based on the reference document, the article proposes the way to calculate the errors of indication and associated measurement uncertainties, by resorting to the general information provided by the calibration certificate of a balance (non-automatic weighing instruments, shortly NAWI used in medical field. The paper may be also considered a useful guideline for: operators working in laboratories accredited in medical (or other various fields where the weighing operations are part of their testing activities; test houses, laboratories, or manufacturers using calibrated non-automatic weighing instruments for measurements relevant for the quality of production subject to QM requirements (e.g. ISO 9000 series, ISO 10012, ISO/IEC 17025; bodies accrediting laboratories; accredited laboratories for the calibration of NAWI. Article refers only to electronic weighing instruments having maximum capacity up to 30 kg. Starting from the results provided by a calibration certificate it is presented an example of calculation.

The Safeguards Analytical Laboratory (SAL) in the Agency's safeguards measurement system activity in 1990

International Nuclear Information System (INIS)

Bagliano, G.; Cappis, J.; Deron, S.; Parus, J.L.

1991-05-01

The IAEA applies Safeguards at the request of a Member State to whole or part of its nuclear materials. The verification of nuclear material accountability still constitutes the fundamental method of control, although sealing and surveillance procedures play an important complementary and increasing role in Safeguards. A small fraction of samples must still be analyzed at independent analytical laboratories using conventional Destructive Analytical (DA) methods of highest accuracy in order to verify that small potential biases in the declarations of the State are not masking protracted diversions of significant quantities of fissile materials. The Safeguards Analytical Laboratory (SAL) is operated by the Agency's Laboratories at Seibersdorf to provide to the Department of Safeguards and its inspectors such off-site Analytical Services, in collaboration with the Network of Analytical Laboratories (NWAL) of the Agency. In the last years SAL and the Safeguards DA Services have become more directly involved in the qualification and utilization of on-site analytical instrumentation such as K-edge X-Ray absorptiometers and quadrupole mass spectrometers. The nature and the origin of the samples analyzed, the measurements usually requested by the IAEA inspectors, the methods and the analytical techniques available at SAL and at the Network of Analytical Laboratories (NWAL) with the performances achieved during the past years are described and discussed in several documents. This report gives an evaluation compared with 1989 of the volume and the quality of the analyses reported in 1990 by SAL and by the NWAL in reply to requests of IAEA Safeguards inspectors. The reports summarizes also on-site DA developments and support provided by SAL to the Division of Safeguards Operation and special training courses to the IAEA Safeguards inspectors. 55 refs, 7 figs, 15 tabs

Laboratory measurements of the solute transport properties of samples from the Bradwell, Elstow, Fulbeck and Killingholme site investigations

International Nuclear Information System (INIS)

Gilling, D.; Jefferies, N.L.; Lineham, T.R.

1987-12-01

The diffusivity and hydraulic conductivity of geological samples collected during the site investigations at Bradwell, Elstow, Fulbeck and Killingholme have been determined. Comparison between laboratory permeability measurements and in-situ permeability measurements for the mudstone units may give some indication of the importance of fissure flow at the sites. (author)

Study of efficacy in a mercury-free flat discharge fluorescent lamp using a zero-dimensional positive column model

CERN Document Server

Shiga, T; Boeuf, J P; Mikoshiba, S

2003-01-01

A zero-dimensional model of the positive column in Ar/Ne/Xe gas mixtures has been developed to help understand the measured dependence of the efficacy on operating conditions in a mercury-free flat fluorescent lamp in a dielectric barrier geometry. The experimental conditions are such that the radiation from the discharge is homogeneous over most of the discharge voltage. The model uses as input the discharge current waveform from the experiments, and it yields the time variations of the mean electron energy and the species densities. From these quantities we calculate the number of vacuum ultraviolet (VUV) photons emitted by the xenon resonance atoms and excimers during one current pulse and the efficiency for generation of VUV radiation in the positive column, which are compared with the measured luminance and efficacy for various voltages, pulse intervals, and lamp sizes. Over the range of conditions studied, we find that most electrical energy dissipated in xenon excitation is converted to VUV radiation; ...

Collection of URL measurement data in 2007 at the Horonobe Underground Research Laboratory project

International Nuclear Information System (INIS)

Yamasaki, Masanao; Funaki, Hironori; Niinuma, Hiroaki; Fujikawa, Daisuke; Sanada, Hiroyuki; Hiraga, Naoto; Tsusaka, Kimikazu; Yamaguchi, Takehiro

2008-11-01

The Horonobe Underground Research Laboratory (URL) Project has being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host sedimentary formations at Horonobe, northern Hokkaido. The project consists of two major research areas, Geoscientific Research' and 'R and D on Geological Disposal', and proceeds in three overlapping phases, 'Phase I: Surface-based investigation', 'Phase II: Construction' and 'Phase III: Operation', over a period of 20 years. The Phase I geoscientific research was planned from March 2001 to March 2006 in parallel with design and execution scheme on URL facilities. In addition, identifying key issues that need to be addressed in the Phase II/III investigations was planned. At the beginning of the Phase II investigations, an investigation report titled 'Measurement Plan and Observational Construction Program on Shaft Excavation at the Horonobe Underground Research Laboratory Project' (hereinafter referred to as 'Observational Construction Program') was published. The Observational Construction Program summarizes the followings from the results of the Phase I investigations: measurements for safety and reasonable constructions, enhancement of shaft design and construction technologies and evaluation of appropriateness for the deep geological environment model estimated before shaft excavation. This report summarizes the measurements data acquired at the Ventilation Shaft, the East Shaft and the drifts in 2007 based on the Observational Construction Program. The report summarizes for the purpose of the following: sharing the investigation and measurements data, preventing the loss of them and acquisition the basic data for carrying out the Observational Construction Program. Two DVD-ROMs are attached as an appendix. (J.P.N.)

Vacuum-Ultraviolet Photovoltaic Detector.

Science.gov (United States)

Zheng, Wei; Lin, Richeng; Ran, Junxue; Zhang, Zhaojun; Ji, Xu; Huang, Feng

2018-01-23

Over the past two decades, solar- and astrophysicists and material scientists have been researching and developing new-generation semiconductor-based vacuum ultraviolet (VUV) detectors with low power consumption and small size for replacing traditional heavy and high-energy-consuming microchannel-detection systems, to study the formation and evolution of stars. However, the most desirable semiconductor-based VUV photovoltaic detector capable of achieving zero power consumption has not yet been achieved. With high-crystallinity multistep epitaxial grown AlN as a VUV-absorbing layer for photogenerated carriers and p-type graphene (with unexpected VUV transmittance >96%) as a transparent electrode to collect excited holes, we constructed a heterojunction device with photovoltaic detection for VUV light. The device exhibits an encouraging VUV photoresponse, high external quantum efficiency (EQE) and extremely fast tempera response (80 ns, 10 4 -10 6 times faster than that of the currently reported VUV photoconductive devices). This work has provided an idea for developing zero power consumption and integrated VUV photovoltaic detectors with ultrafast and high-sensitivity VUV detection capability, which not only allows future spacecraft to operate with longer service time and lower launching cost but also ensures an ultrafast evolution of interstellar objects.

Final report on the proficiency test of the Analytical Laboratories for the Measurement of Environmental Radioactivity (ALMERA) network

International Nuclear Information System (INIS)

Shakhashiro, A.; Radecki, Z.; Trinkl, A.; Sansone, U.; Benesch, T.

2005-08-01

This report presents the statistical evaluation of results from the analysis of 12 radionuclides in 8 samples within the frame of the First Proficiency Test of Analytical Laboratories for the Measurement Environmental RAdioactivity (ALMERA) organized in 2001-2002 by the Chemistry Unit, Agency's Laboratory in Seibersdorf. The results were evaluated by using appropriate statistical means to assess laboratory analytical performance and to estimate the overall performance for the determination of each radionuclide. Evaluation of the analytical data for gamma emitting radionuclides showed that 68% of data obtained a 'Passed' final score for both the trueness and precision criteria applied to this exercise. However, transuranic radionuclides obtained only 58% for the same criteria. (author)

Sequim Marine Research Laboratory routine environmental measurements during CY-1977

International Nuclear Information System (INIS)

Fix, J.J.; Blumer, P.J.

1978-06-01

Beginning in 1976, a routine environmental program was established at the Marine Research Laboratory (MRL) at Sequim, Washington. The program is intended to demonstrate the negligible impact of current MRL operations on the surrounding environs and to provide baseline data through which any cumulative impact could be detected. The sampling frequency is greater during the first 2 years of the program to provide sufficient initial information to allow reliable estimates of observed radionuclide concentrations and to construct a long-term sampling program. The program is designed, primarily, to determine levels of radioactivity present in selected biota in Sequim Bay. The biota were selected because of their presence near the laboratory and their capacity to concentrate trace elements. Other samples were obtained to determine the radionuclides in Sequim Bay and laboratory drinking water, as well as the ambient radiation exposure levels and surface deposition of fallout radionuclides for the laboratory area. Appendix A provides a summary of the analytical methods used. The present document includes data obtained during CY 1977 in addition to CY-1976 data published previously

Measurements of energetic particle radiation in transit to Mars on the Mars Science Laboratory.

Science.gov (United States)

Zeitlin, C; Hassler, D M; Cucinotta, F A; Ehresmann, B; Wimmer-Schweingruber, R F; Brinza, D E; Kang, S; Weigle, G; Böttcher, S; Böhm, E; Burmeister, S; Guo, J; Köhler, J; Martin, C; Posner, A; Rafkin, S; Reitz, G

2013-05-31

The Mars Science Laboratory spacecraft, containing the Curiosity rover, was launched to Mars on 26 November 2011, and for most of the 253-day, 560-million-kilometer cruise to Mars, the Radiation Assessment Detector made detailed measurements of the energetic particle radiation environment inside the spacecraft. These data provide insights into the radiation hazards that would be associated with a human mission to Mars. We report measurements of the radiation dose, dose equivalent, and linear energy transfer spectra. The dose equivalent for even the shortest round-trip with current propulsion systems and comparable shielding is found to be 0.66 ± 0.12 sievert.

Laboratory Measurements of Optical and Physical Properties of Individual Lunar Dust Grains

Science.gov (United States)

Abbas, M. M.; Tankosic, D.; Craven, P. D.; Hoover, R. B.

2006-01-01

The lunar surface is covered with a thick layer of sub-micron/micron size dust grains formed by meteoritic impact over billions of years. The fine dust grains are levitated and transported on the lunar surface, and transient dust clouds over the lunar horizon were observed by experiments during the Apollo 17 mission. Theoretical models suggest that the dust grains on the lunar surface are charged by the solar UV radiation as well as the solar wind. Even without any physical activity, the dust grains are levitated by electrostatic fields and transported away from the surface in the near vacuum environment of the Moon. The current dust charging and levitation models, however, do not fully explain the observed phenomena. Since the abundance of dust on the Moon's surface with its observed adhesive characteristics has the potential of severe impact on human habitat and operations and lifetime of a variety of equipment, it is necessary to investigate the charging properties and the lunar dust phenomena in order to develop appropriate mitigating strategies. Photoelectric emission induced by the solar UV radiation with photon energies higher than the work function of the grain materials is recognized to be the dominant process for charging of the lunar dust, and requires measurements of the photoelectric yields to determine the charging and equilibrium potentials of individual dust grains. In this paper, we present the first laboratory measurements of the photoelectric yields of individual sub-micron/micron size dust grains selected from sample returns of Apollo 17, and Luna 24 missions, as well as similar size dust grains from the JSC-1 simulants. The experimental results were obtained on a laboratory facility based on an electrodynamic balance that permits a variety of experiments to be conducted on individual sub-micron/micron size dust grains in simulated space environments. The photoelectric emission measurements indicate grain size dependence with the yield

IR + VUV double resonance spectroscopy and extended density functional theory studies of ketone solvation by alcohol: 2-butanone·(methanol)n, n = 1-4 clusters.

Science.gov (United States)

Shin, Joong-Won; Bernstein, Elliot R

2017-09-28

Infrared plus vacuum ultraviolet (IR + VUV) photoionization vibrational spectroscopy of 2-butanone/methanol clusters [MEK·(MeOH) n , n = 1-4] is performed to explore structures associated with hydrogen bonding of MeOH molecules to the carbonyl functional group of the ketone. IR spectra and X3LYP/6-31++G(d,p) calculations show that multiple isomers of MEK·(MeOH) n are generated in the molecular beam as a result of several hydrogen bonding sites available to the clusters throughout the size range investigated. Isomer interconversion involving solvating MeOH rearrangement should probably occur for n = 1 and 2. The mode energy for a hydrogen bonded OH stretching transition gradually redshifts as the cluster size increases. Calculations suggest that the n = 3 cluster isomers adopt structures in which the MEK molecule is inserted into the cyclic MeOH hydrogen bond network. In larger structures, the cyclic network may be preserved.

Laboratory measurements of grain-bedrock interactions using inertial sensors.

Science.gov (United States)

Maniatis, Georgios; Hoey, Trevor; Hodge, Rebecca; Valyrakis, Manousos; Drysdale, Tim

2016-04-01

Sediment transport in steep mountain streams is characterized by the movement of coarse particles (diameter c.100 mm) over beds that are not fully sediment-covered. Under such conditions, individual grain dynamics become important for the prediction of sediment movement and subsequently for understanding grain-bedrock interaction. Technological advances in micro-mechanical-electrical systems now provide opportunities to measure individual grain dynamics and impact forces from inside the sediments (grain inertial frame of reference) instead of trying to infer them indirectly from water flow dynamics. We previously presented a new prototype sensor specifically developed for monitoring sediment transport [Maniatis et al. EGU 2014], and have shown how the definition of the physics of the grain using the inertial frame and subsequent derived measurements which have the potential to enhance the prediction of sediment entrainment [Maniatis et al. 2015]. Here we present the latest version of this sensor and we focus on beginning of the cessation of grain motion: the initial interaction with the bed after the translation phase. The sensor is housed in a spherical case, diameter 80mm, and is constructed using solid aluminum (density = 2.7 kg.m-3) after detailed 3D-CAD modelling. A complete Inertial Measurement Unit (a combination of micro- accelerometer, gyroscope and compass) was placed at the center of the mass of the assembly, with measurement ranges of 400g for acceleration, and 1200 rads/sec for angular velocity. In a 0.9m wide laboratory flume, bed slope = 0.02, the entrainment threshold of the sensor was measured, and the water flow was then set to this value. The sensor was then rolled freely from a static cylindrical bar positioned exactly on the surface of the flowing water. As the sensor enters the flow we record a very short period of transport (1-1.5 sec) followed by the impact on the channel bed. The measured Total Kinetic Energy (Joules) includes the

Genetic influence on blood pressure measured in the office, under laboratory stress and during real life

NARCIS (Netherlands)

Wang, Xiaoling; Ding, Xiuhua; Su, Shaoyong; Harshfield, Gregory; Treiber, Frank; Snieder, Harold

To determine to what extent the genetic influences on blood pressure (BP) measured in the office, under psychologically stressful conditions in the laboratory and during real life are different from each other. Office BP, BP during a video game challenge and a social stressor interview, and 24-h

Laboratory-scale measurements of effective relative permeability for layered sands

Energy Technology Data Exchange (ETDEWEB)

Butts, M.G.; Korsgaard, S.

1996-12-31

Predictions of the impact of remediation or the extent of contamination resulting from spills of gasoline, solvents and other petroleum products, must often be made in complex geological environments. Such problems can be treated by introducing the concept of effective parameters that incorporate the effects of soil layering or other heterogeneities into a large-scale flow description. Studies that derive effective multiphase parameters are few, and approximations are required to treat the non-linear multiphase flow equations. The purpose of this study is to measure effective relative permeabilities for well-defined multi-layered soils at the laboratory scale. Relative permeabilities were determined for homogeneous and layered, unconsolidated sands using the method of Jones and Roszelle (1978). The experimental data show that endpoint relative permeabilities are important in defining the shape of the relative permeability curves, but these cannot be predicted by estimation methods base on capillary pressure data. The most significant feature of the measured effective relative permeability curves is that the entrapped (residual) oil saturation is significantly larger than the residual saturation of the individual layers. This observation agrees with previous theoretical predictions of large-scale entrapment Butts, 1993 and (1995). Enhanced entrapment in heterogeneous soils has several important implications for spill remediation, for example, the reduced efficiency of direct recovery. (au) 17 refs.

Laboratory-scale measurements of effective relative permeability for layered sands

International Nuclear Information System (INIS)

Butts, M.G.; Korsgaard, S.

1996-01-01

Predictions of the impact of remediation or the extent of contamination resulting from spills of gasoline, solvents and other petroleum products, must often be made in complex geological environments. Such problems can be treated by introducing the concept of effective parameters that incorporate the effects of soil layering or other heterogeneities into a large-scale flow description. Studies that derive effective multiphase parameters are few, and approximations are required to treat the non-linear multiphase flow equations. The purpose of this study is to measure effective relative permeabilities for well-defined multi-layered soils at the laboratory scale. Relative permeabilities were determined for homogeneous and layered, unconsolidated sands using the method of Jones and Roszelle (1978). The experimental data show that endpoint relative permeabilities are important in defining the shape of the relative permeability curves, but these cannot be predicted by estimation methods base on capillary pressure data. The most significant feature of the measured effective relative permeability curves is that the entrapped (residual) oil saturation is significantly larger than the residual saturation of the individual layers. This observation agrees with previous theoretical predictions of large-scale entrapment Butts, 1993 and (1995). Enhanced entrapment in heterogeneous soils has several important implications for spill remediation, for example, the reduced efficiency of direct recovery. (au) 17 refs

The influence of uncertainties of measurements in laboratory performance evaluation using an intercomparison program of radionuclide assays in environmental samples

International Nuclear Information System (INIS)

Tauhata, Luiz; Elizabeth Couto Machado Vianna, Maria; Eduardo de Oliveira, Antonio; Cristina de Melo Ferreira, Ana; Julia Camara da Silva Braganca, Maura; Faria Clain, Almir

2006-01-01

To show the influence of measurement uncertainties in performance evaluation of laboratories, data from 42 comparison runs were evaluated using two statistical criteria. The normalized standard deviation, D, used by US EPA, that mainly takes into account the accuracy, and the normalized deviation, E, that includes the individual laboratory uncertainty used for performance evaluation in the key-comparisons by BIPM. The results show that data evaluated by the different criteria give a significant deviation of laboratory performance in each radionuclide assay when we analyse a large quantity of data

[ISO 15189 medical laboratory accreditation].

Science.gov (United States)

Aoyagi, Tsutomu

2004-10-01

This International Standard, based upon ISO/IEC 17025 and ISO 9001, provides requirements for competence and quality that are particular to medical laboratories. While this International Standard is intended for use throughout the currently recognized disciplines of medical laboratory services, those working in other services and disciplines will also find it useful and appropriate. In addition, bodies engaged in the recognition of the competence of medical laboratories will be able to use this International Standard as the basis for their activities. The Japan Accreditation Board for Conformity Assessment (AB) and the Japanese Committee for Clinical Laboratory Standards (CCLS) are jointly developing the program of accreditation of medical laboratories. ISO 15189 requirements consist of two parts, one is management requirements and the other is technical requirements. The former includes the requirements of all parts of ISO 9001, moreover it includes the requirement of conformity assessment body, for example, impartiality and independence from any other party. The latter includes the requirements of laboratory competence (e.g. personnel, facility, instrument, and examination methods), moreover it requires that laboratories shall participate proficiency testing(s) and laboratories' examination results shall have traceability of measurements and implement uncertainty of measurement. Implementation of ISO 15189 will result in a significant improvement in medical laboratories management system and their technical competence. The accreditation of medical laboratory will improve medical laboratory service and be useful for patients.

Laboratory Measurements of the Dielectronic Recombination Satellite Transitions of He-Like FE XXV and H-Like FE XXVI

Science.gov (United States)

Gu, M. F.; Beiersdorfer, P.; Brown, G. V.; Graf, A.; Kelley, R. I.; Kilbourne, C. A.; Porter, F. S.; Kahn, S. M,

2012-01-01

We present laboratory spectra of dielectronic recombination (DR) satellite transitions attached to the He-like and H-like iron resonance lines obtained with the NASA Goddard Space Flight Center X-ray calorimeter and produced by a thermal plasma simu1ation technique on the EBIT-I electron beam ion trap at the Lawrence Livermore National Laboratory. We demonstrate that the calorimeter has sufficient spectral resolution in the 6-9 keV range to provide reliable measurements not only of standard DR satellite to resonance line intensities but also of DR satellite to DR satellite ratios that can be used to diagnose nonthermal electron distributions. Electron temperatures derived from the measured line intensities are consistent with the temperature of the simulated plasma. Temperature measurements based on DR satellite transitions have significant advantages over those based on collisional ionization equilibrium or continuum shape. Thus, successful demonstration of this method with the X-ray calorimeter is an important step fur its application in X-ray astronomy.