WorldWideScience

Sample records for 2-h post-ogtt plasma

  1. Clinical significance of 2 h plasma concentrations of first-line anti-tuberculosis drugs

    Prahl, Julie B; Johansen, Isik S; Cohen, Arieh S;

    2014-01-01

    OBJECTIVES: To study 2 h plasma concentrations of the first-line tuberculosis drugs isoniazid, rifampicin, ethambutol and pyrazinamide in a cohort of patients with tuberculosis in Denmark and to determine the relationship between the concentrations and the clinical outcome. METHODS: After 6...... patients. Therapy failure occurred more frequently when the concentrations of isoniazid and rifampicin were both below the normal ranges (P = 0.013) and even more frequently when they were below the median 2 h drug concentrations obtained in the study (P = 0.005). CONCLUSIONS: At 2 h, plasma concentrations...

  2. Optical and electrical study of Ar-C2 H2 and N2-C2 H2 RF-excited plasmas in a small cylindrical reactor

    An optical and electrical investigation were carried out of organic plasmas obtained from DC and RF discharges in mixtures of Arc-C2 H2 in a small cylindrical reactor operating under pressures ranging from 0.3 to 1.0 Torr. The Actinometric Optical Emission Spectroscopy was used to follow the trends of C H and H species in the reactive plasma, for different pressures and power coupled to the reactor. The results showed a decreasing of C H concentration with the increasing of pressure and DC power and an increasing of the H concentration with the increasing of the pressure. The electrical investigation was performed using pulsed Langmuir probe technique, indicating typical electronic temperature around 2 eV. The effects of film deposition on the probe tip surface was analyzed using. Ar as reference gas. The results obtained indicated application of the probe during few period of sweep cycle. (author). 8 refs, 5 figs

  3. Electrical and optical characterization of pulsed plasma of N2 H2

    Martínez, H.; Yousif, F. B.

    2008-03-01

    This paper considers the electrical and optical characterization of glow discharge pulsed plasma in N2/H2 gas mixtures at a pressures range between 0.5 and 4.0 Torr and discharge current between 0.2 and 0.6 A. Electron temperature and ion density measurements were performed employing a double Langmuir probe. They were found to increase rapidly as the H2 percentage in the mixture was increased up to 20%. This increase slows down as the H2 percentage in the gas mixture was increased above 20% at the same pressure. Emission spectroscopy was employed to observe emission from the pulsed plasma of a steady-state electric discharge. The discharge mainly emits within the range 280 500 nm. The emission consists of N2 (C-X) 316, 336, 358 nm narrow peaks and a broad band with a maximum at λmax = 427 nm. Also lines of N2, N2 + and NH excited states were observed. All lines and bands have their maximum intensity at the discharge current of 0.417 A. The intensities of the main bands and spectral lines are determined as functions of the total pressure and discharge current. Agreement with other theoretical and experimental groups was established.

  4. Plasma-catalytic Selective Reduction of NO with C2H4 in the Presence of Excess Oxygen

    Qi SUN; Ai Min ZHU; Xue Feng YANG; Jin Hai NIU; Yong XU; Zhi Min SONG; Jing LIU

    2005-01-01

    This paper reports observations of significant synergistic effects between dielectric barrier discharge (DBD) plasmas and Cu-ZSM-5 catalysts for C2H4 selective reduction of NOx at250 ℃ in the presence of excess oxygen by using a one-stage plasma-over-catalyst (POC) reactor.With the reactant gas mixture of 530 ppm NO, 650 ppm C2H4, 5.8% O2 in N2and GHSV = 12000h-1, the pure catalytic, pure plasma-induced (discharges over fused silica pellets) and plasmacatalytic (in the POC reactor) NOx conversion are 39%, 1.5% and 79%, respectively. The in-situ optical emission spectra of the reactive systems imply some short-lived active species formed from plasma-induced and plasma-catalytic processes may be responsible to the observed synergistic effects in this one-stage POC system.

  5. Preparation of hydrogenated diamond-like carbon films using high-density pulsed plasmas of Ar/C2H2 and Ne/C2H2 mixture

    Kimura, Takashi; Kamata, Hikaru

    2016-07-01

    Hydrogenated diamond-like carbon films are prepared using reactive high-density pulsed plasmas of Ar/C2H2 and Ne/C2H2 mixture in the total pressure range from 0.5 to 2 Pa. The plasmas are produced using a reactive high-power impulse magnetron sputtering (HiPIMS) system. A negative pulse voltage of ‑500 V is applied to the substrate for a period of 15 µs in the afterglow mode. The growth rate does not strongly depend on the type of ambient gas but it markedly increases to about 2.7 µm/h at a C2H2 fraction of 10% and a total pressure of 2 Pa with increasing C2H2 fraction. The marked increase in the growth rate means that the HiPIMS system can be regarded as a plasma source for the chemical vapor deposition process. The hardness of the films prepared by Ne/C2H2 plasmas is somewhat higher than that of the films prepared by Ar/C2H2 plasmas under the same operating conditions, and the difference becomes larger as the pressure increases. The hardness of the films prepared by Ne/C2H2 plasmas ranges between 11 and 18 GPa. In the Raman spectra, two very broad overlapping bands are assigned as the G (graphite) and D (disorder) bands. The peak position of the G band is roughly independent of the total pressure, whereas the FWHM of the G peak decreases with increasing total pressure as a whole.

  6. Controlled modification of mono- and bilayer graphene in O2, H2 and CF4 plasmas

    In this work, covalent modification of mono- and bilayer graphene is achieved using tetrafluoromethane (CF4), oxygen and hydrogen RF plasma. Controlled modification of graphene is usually difficult to achieve, in particular with oxygen plasma, which is rather aggressive and usually leads to etching of graphene. Here we use x-ray photoelectron spectroscopy and Raman spectroscopy to show that mild plasma conditions and fine tuning of the number of functional groups can be obtained in all plasmas by varying parameters such as exposure time and sample position inside the chamber. We found that even for the usual harsh oxygen treatment the defect density could be lowered, down to one defect for 3.5 × 104 carbon atoms. Furthermore, we show that CF4 plasma leads to functionalization without etching and that graphene becomes an insulator at saturation coverage. In addition, the reactivity of mono- and bilayer graphene was studied revealing faster modification of monolayer in oxygen and CF4 plasma, in agreement with previous works. In contrast, similar modification rates were observed for both mono- and bilayer during hydrogenation. We attribute this discrepancy to the presence of more energetic species in the hydrogen plasma such as positive ions that could play a role in the functionalization process. (paper)

  7. Inductively coupled plasma etching of chemical-vapor-deposited amorphous carbon in N2/H2/Ar chemistries

    In this study, we investigated the etching characteristics and the mechanism of an amorphous carbon (a-C) layer for a multi-level resist (MLR) structure. CVD (chemical-vapor-deposited) a-C layers with a SiO2 hard-mask were etched in an ICP (inductively coupled plasma) etcher while varying the process parameters, such as the top electrode power, the bottom electrode power, and the gas flow ratio in the N2/H2/Ar plasma. The results indicated that the etch rate and the profile angle of the CVD a-C increased with increasing H2 gas flow ratio in the N2/H2/Ar plasma. As the H2 flow ratio increased, the etch rate and the profile angle increase, due to the increased formation of H radicals in the plasma, leading to enhanced chemical reactions with carbon atoms. Also, the etch rate of the CVD a-C increased with increasing top and bottom electrode powers.

  8. Plasma chemistry and diagnostic in an ArN2H2 microwave expanding plasma used for nitriding treatments

    Touimi, Said; Jauberteau, Jean-Louis; Jauberteau, Isabelle; Aubreton, Jacques

    2010-01-01

    Abstract This paper reports on mass spectrometry analysis performed downstream a microwave discharge in Ar-N 2 -H 2 gas mixture in nitriding conditions. Investigations are focused on the main simple radicals NH 2, NH and N, and on the molecular species NH 3 and N 2 H 2 produced. Because of wall desorptions due to catalytic effects, we must develop a specific method taking into account both wall desorption and dissociative ionization effects, in order to correct the mass spectrometer signal...

  9. Ammonia formation in N2/H2 plasmas on ITER-relevant plasma facing materials: Surface temperature and N2 plasma content effects

    Ammonia production in N2/H2 direct current glow discharge plasmas, with nitrogen concentrations from 1.5% to 33%, different wall materials (tungsten, stainless steel and aluminium as a proxy for beryllium) and surface temperatures up to 350 °C has been investigated. Ammonia yields on the exposed materials have been deduced, resulting in different values depending on the wall material, its temperature and N2 plasma content. The results indicate weak wall temperature dependence in tungsten and stainless steel. However, wall temperatures above 300 °C have a very clear influence on aluminium walls, as almost all the molecular N2 depleted from the gas phase is converted into ammonia. The amount of implanted N seems to have a direct impact on the ammonia formation yield, pointing to the competition between N implantation and N/H–N/N recombination on the walls as the key mechanism of the ammonia formation

  10. Properties of Cr(C,N) hard coatings deposited in Ar-C2H2-N2 plasma

    Several chromium carbonitride (Cr-(C,N)) coatings were prepared with different C:N ratios by varying the N2 and C2H2 flow. Chromium nitride (Cr-N) and chromium carbide (Cr-C) coatings were also prepared for comparison. The coatings were deposited in two different ion-plating systems: by reactive evaporation in BAI730M (Balzers) apparatus at high temperature (450 deg. C) and by reactive sputtering in plasma-beam Sputron (Balzers) apparatus at low temperature (200 deg. C). Among mechanical properties microhardness, adhesion (measured by scratch test) and surface roughness were evaluated. Oxidation of the coatings was carried out by heating the samples at temperatures of 750-900 deg. C in an oxygen atmosphere. Crystal structure and microstructure were studied by XRD, TEM and SEM. Chemical State of the elements was observed by XPS. The concentration and depth profiles of the samples oxidized at various temperatures were measured by AES, EDX and GDOES

  11. Detailed study of the plasma-activated catalytic generation of ammonia in N2-H2 plasmas

    van Helden, J. H.; Wagemans, W.; Yagci, G.; Zijlmans, R. A. B.; Schram, D. C.; Engeln, R.; Lombardi, G.; Stancu, G. D.; Röpcke, J.

    2007-02-01

    We investigated the efficiency and formation mechanism of ammonia generation in recombining plasmas generated from mixtures of N2 and H2 under various plasma conditions. In contrast to the Haber-Bosch process, in which the molecules are dissociated on a catalytic surface, under these plasma conditions the precursor molecules, N2 and H2, are already dissociated in the gas phase. Surfaces are thus exposed to large fluxes of atomic N and H radicals. The ammonia production turns out to be strongly dependent on the fluxes of atomic N and H radicals to the surface. By optimizing the atomic N and H fluxes to the surface using an atomic nitrogen and hydrogen source ammonia can be formed efficiently, i.e., more than 10% of the total background pressure is measured to be ammonia. The results obtained show a strong similarity with results reported in literature, which were explained by the production of ammonia at the surface by stepwise addition reactions between adsorbed nitrogen and hydrogen containing radicals at the surface and incoming N and H containing radicals. Furthermore, our results indicate that the ammonia production is independent of wall material. The high fluxes of N and H radicals in our experiments result in a passivated surface, and the actual chemistry, leading to the formation of ammonia, takes place in an additional layer on top of this passivated surface.

  12. Spectroscopic study of H2 microwave plasmas with small admixtures of CH4 and B2H6 used for doped diamond deposition

    Microwave (MW) H2 plasmas with small admixtures of CH4 and/or B2H6 used for doped diamond deposition have been studied by infrared absorption and optical emission spectroscopy (OES) techniques. The experiments were carried out in order to analyze the dependence of the plasma chemistry on several parameters in the MW discharges, such as power, pressure and gas mixture, at relatively high pressures, i.e. up to 300 mbar, and power values, i.e. up to 4 kW. The evolution of the concentrations of five stable molecules, CH4, C2H2, C2H4, C2H6 and B2H6, was monitored in the plasma processes by in situ infrared tunable diode laser absorption spectroscopy. OES was used simultaneously to gather complementary information about the concentration of the boron atom. One target was the determination of the precursors' fragmentation rates and the conversion rates to the molecular reaction products. The analysis of correlations between the power and pressure of the plasma and molecular concentrations, and the differences found with CH4 and B2H6 admixtures were another focus of interest. The degree of dissociation of the carbon containing precursor molecule CH4 varied between 35% and 75%, while the decomposition of diborane, the boron precursor, varied between 85% and 97%. By analyzing the development of the molecular concentrations with changes of gas mixtures, pressure and plasma power values, it was found that (i) C2H2 is the most abundant reaction product in the plasma in the case of methane admixture and (ii) the boron atom concentration depends strongly on the presence of hydrocarbons in the plasma. The fragmentation efficiencies of methane and of diborane (RF(CH4) ≈ (1–2) × 1015 molecules J−1, RF(B2H6) ≈ (0.4–1.4) × 1013 molecules J−1) and the conversion efficiencies to the molecular products (RC(product) ≈ 1013–1015 molecules J−1) have been determined for different gas mixtures and plasma power, and pressure values. The boron atom

  13. Spectroscopic study of H2 microwave plasmas with small admixtures of CH4 and B2H6 used for doped diamond deposition

    Hamann, S.; Rond, C.; Pipa, A. V.; Wartel, M.; Lombardi, G.; Gicquel, A.; Röpcke, J.

    2014-08-01

    Microwave (MW) H2 plasmas with small admixtures of CH4 and/or B2H6 used for doped diamond deposition have been studied by infrared absorption and optical emission spectroscopy (OES) techniques. The experiments were carried out in order to analyze the dependence of the plasma chemistry on several parameters in the MW discharges, such as power, pressure and gas mixture, at relatively high pressures, i.e. up to 300 mbar, and power values, i.e. up to 4 kW. The evolution of the concentrations of five stable molecules, CH4, C2H2, C2H4, C2H6 and B2H6, was monitored in the plasma processes by in situ infrared tunable diode laser absorption spectroscopy. OES was used simultaneously to gather complementary information about the concentration of the boron atom. One target was the determination of the precursors' fragmentation rates and the conversion rates to the molecular reaction products. The analysis of correlations between the power and pressure of the plasma and molecular concentrations, and the differences found with CH4 and B2H6 admixtures were another focus of interest. The degree of dissociation of the carbon containing precursor molecule CH4 varied between 35% and 75%, while the decomposition of diborane, the boron precursor, varied between 85% and 97%. By analyzing the development of the molecular concentrations with changes of gas mixtures, pressure and plasma power values, it was found that (i) C2H2 is the most abundant reaction product in the plasma in the case of methane admixture and (ii) the boron atom concentration depends strongly on the presence of hydrocarbons in the plasma. The fragmentation efficiencies of methane and of diborane (RF(CH4) ≈ (1-2) × 1015 molecules J-1, RF(B2H6) ≈ (0.4-1.4) × 1013 molecules J-1) and the conversion efficiencies to the molecular products (RC(product) ≈ 1013-1015 molecules J-1) have been determined for different gas mixtures and plasma power, and pressure values. The boron atom balance, in relation to the

  14. Growth Conditions and Cell Cycle Phase Modulate Phase Transition Temperatures in RBL-2H3 Derived Plasma Membrane Vesicles.

    Erin M Gray

    Full Text Available Giant plasma membrane vesicle (GPMV isolated from a flask of RBL-2H3 cells appear uniform at physiological temperatures and contain coexisting liquid-ordered and liquid-disordered phases at low temperatures. While a single GPMV transitions between these two states at a well-defined temperature, there is significant vesicle-to-vesicle heterogeneity in a single preparation of cells, and average transition temperatures can vary significantly between preparations. In this study, we explore how GPMV transition temperatures depend on growth conditions, and find that average transition temperatures are negatively correlated with average cell density over 15°C in transition temperature and nearly three orders of magnitude in average surface density. In addition, average transition temperatures are reduced by close to 10°C when GPMVs are isolated from cells starved of serum overnight, and elevated transition temperatures are restored when serum-starved cells are incubated in serum-containing media for 12 h. We also investigated variation in transition temperature of GPMVs isolated from cells synchronized at the G1/S border through a double Thymidine block and find that average transition temperatures are systematically higher in GPMVs produced from G1 or M phase cells than in GPMVs prepared from S or G1 phase cells. Reduced miscibility transition temperatures are also observed in GPMVs prepared from cells treated with TRAIL to induce apoptosis or sphingomyelinase, and in some cases a gel phase is observed at temperatures above the miscibility transition in these vesicles. We conclude that at least some variability in GPMV transition temperature arises from variation in the local density of cells and asynchrony of the cell cycle. It is hypothesized that GPMV transition temperatures are a proxy for the magnitude of lipid-mediated membrane heterogeneity in intact cell plasma membranes at growth temperatures. If so, these results suggest that cells tune

  15. The quenching effect of hydrogen on the nitrogen in metastable state in atmospheric-pressure N2-H2 microwave plasma torch

    The atmospheric-pressure microwave N2-H2 plasma torch is generated and diagnosed by optical emission spectroscopy. It is found that a large amount of N atoms and NH radicals are generated in the plasma torch and the emission intensity of N2+ first negative band is the strongest over the spectra. The mixture of hydrogen in nitrogen plasma torch causes the morphology of the plasma discharge to change with appearance that the afterglow shrinks greatly and the emission intensity of N2+ first negative band decreases with more hydrogen mixed into nitrogen plasma. In atmospheric-pressure microwave-induced plasma torch, the hydrogen imposes a great influence on the characteristics of nitrogen plasma through the quenching effect of the hydrogen on the metastable state of N2

  16. Etching of low-k materials for microelectronics applications by means of a N2/H2 plasma: modeling and experimental investigation

    In this paper, we investigate the etch process of so-called low-k organic material by means of a N2/H2 capacitively coupled plasma, as applied in the micro-electronics industry for the manufacturing of computer chips. In recent years, such an organic material has emerged as a possible alternative for replacing bulk SiO2 as a dielectric material in the back-end-of-line, because of the smaller parasitic capacity between adjacent conducting lines, and thus a faster propagation of the electrical signals throughout the chip. Numerical simulations with a hybrid plasma model, using an extensive plasma and surface chemistry set, as well as experiments are performed, focusing on the plasma properties as well as the actual etching process, to obtain a better insight into the underlying mechanisms. Furthermore, the effects of gas pressure, applied power and gas composition are investigated to try to optimize the etch process. In general, the plasma density reaches a maximum near the wafer edge due to the so-called ‘edge effect’. As a result, the etch rate is not uniform but will also reach its maximum near the wafer edge. The pressure seems not to have a big effect. A higher power increases the etch rate, but the uniformity becomes (slightly) worse. The gas mixing ratio has no significant effect on the etch process, except when a pure H2 or N2 plasma is used, illustrating the synergistic effects of a N2/H2 plasma. In fact, our calculations reveal that the N2/H2 plasma entails an ion-enhanced etch process. The simulation results are in reasonable agreement with the experimental values. The microscopic etch profile shows the desired anisotropic shape under all conditions under study. (paper)

  17. Effects of hBN Content on the Microstructure and Properties of Atmospheric Plasma-Sprayed NiCr/Cr3C2-hBN Composite Coatings

    Cao, Yuxia

    2016-04-01

    NiCr/Cr3C2-hBN composite coatings with different contents of hBN were prepared by atmospheric plasma-spray technology. The microstructural, mechanical, and tribological properties of the coatings were systematically investigated. The results show that the flowability and apparent density of NiCr/Cr3C2-hBN composite powders, as well as the microhardness and tensile strength of the NiCr/Cr3C2-hBN composite coating, gradually decrease with the increase of hBN in the composite powders. The addition of hBN is benefit to the friction coefficient of the coatings, but it is positive to the wear rate. When the content of hBN is up to 20%, the friction coefficient of the composite coating is lowest, but the wear rate of the composite coating is highest.

  18. PMP1 18-38, a yeast plasma membrane protein fragment, binds phosphatidylserine from bilayer mixtures with phosphatidylcholine: a (2)H-NMR study.

    M. Roux; Beswick, V; Coïc, Y M; Huynh-Dinh, T.; Sanson, A.; Neumann, J M

    2000-01-01

    PMP1 is a 38-residue plasma membrane protein of the yeast Saccharomyces cerevisiae that regulates the activity of the H(+)-ATPase. The cytoplasmic domain conformation results in a specific interfacial distribution of five basic side chains, thought to strongly interact with anionic phospholipids. We have used the PMP1 18-38 fragment to carry out a deuterium nuclear magnetic resonance ((2)H-NMR) study for investigating the interactions between the PMP1 cytoplasmic domain and phosphatidylserine...

  19. HbA1c, fasting and 2 h plasma glucose in current, ex- and never-smokers

    Soulimane, Soraya; Simon, Dominique; Herman, William H;

    2014-01-01

    without known diabetes in 12 DETECT-2 consortium studies and in the French Data from an Epidemiological Study on the Insulin Resistance Syndrome (DESIR) and Telecom studies. Means of three glycaemic variables in current, ex- and never-smokers were modelled by linear regression, with study as a random.......09]). There was a large and unexplained heterogeneity among studies, with I (2) always above 50%; I (2) was little changed after stratification by sex and adjustment for age and BMI. In this study population, current smokers had a prevalence of diabetes that was 1.30% higher as screened by HbA1c and 0.52% lower...... as screened by 2H-PG, in comparison with never-smokers. CONCLUSION/INTERPRETATION: Across this heterogeneous group of studies, current smokers had a higher HbA1c and lower 2H-PG than never-smokers. This will affect the chances of smokers being diagnosed with diabetes....

  20. Generation and loss of reactive oxygen species in low-temperature atmospheric-pressure RF He + O2 + H2O plasmas

    This study focuses on the generation and loss of reactive oxygen species (ROS) in low-temperature atmospheric-pressure RF (13.56 MHz) He + O2 + H2O plasmas, which are of interest for many biomedical applications. These plasmas create cocktails of ROS containing ozone, singlet oxygen, atomic oxygen, hydroxyl radicals, hydrogen peroxide and hydroperoxyl radicals, i.e. ROS of great significance as recognized by the free-radical biology community. By means of one-dimensional fluid simulations (61 species, 878 reactions), the key ROS and their generation and loss mechanisms are identified as a function of the oxygen and water content in the feed gas. Identification of the main chemical pathways can guide the optimization of He + O2 + H2O plasmas for the production of particular ROS. It is found that for a given oxygen concentration, the presence of water in the feed gas decreases the net production of oxygen-derived ROS, while for a given water concentration, the presence of oxygen enhances the net production of water-derived ROS. Although most ROS can be generated in a wide range of oxygen and water admixtures, the chemical pathways leading to their generation change significantly as a function of the feed gas composition. Therefore, care must be taken when selecting reduced chemical sets to study these plasmas. (fast track communication)

  1. Comparative sterilization effectiveness of plasma in O2-H2O2 mixtures and ethylene oxide treatment.

    Silva, J M F; Moreira, A J; Oliveira, D C; Bonato, C B; Mansano, R D; Pinto, T J A

    2007-01-01

    We investigated the influence of variable parameters of plasma sterilization and compared its effectiveness with that of ethylene oxide using a reactive ion etching plasma reactor at 13.56 MHz. Gases tested were pure oxygen and oxygen-hydrogen peroxide mixtures in 190/10, 180/20, and 160/40 sccm ratios with constant gas flow at 200 sccm, pressure at 0.100 torr, radio-frequency power at 25 W, 50 W, 100 W, and 150 W, and temperature below 60 degrees C. Ethylene oxide sterilization was performed using 450 mg/L at 55 degrees C, 60% humidity, and -0.65 and 0.60 kgf/cm2 pressure. The biological indicator was Bacillus atrophaeus ATCC 9372, with exposure times of 3 to 120 min. Observed D values were 215.91, 55.55, 9.19, and 2.98 min for pure oxygen plasma at 25 W, 50 W, 100 W, and 150 W, respectively. Oxygen-hydrogen peroxide plasma produced D values of 6.41 min (190/10), 6.47 min (180/20), and 4.02 min (160/40) at 100 W and 1.47 min (190/10), 3.11 min (180/20), and 1.94 min (160/40) at 150 W. Ethylene oxide processes resulted in a D value of 2.86 min. Scanning electron microscopy analyses showed damage to the spore cortex. PMID:17722487

  2. Investigation of Laser Plasma Chemistry in CO2-N-2-H2O Using O-18 Labeled Water

    Ferus, Martin; Kubelík, Petr; Juha, Libor; Civiš, Svatopluk

    2009-01-01

    Roč. 39, 3-4 (2009), s. 245-245. ISSN 0169-6149 R&D Projects: GA MŠk LC510; GA MŠk(CZ) LC528; GA ČR GA203/06/1278; GA MŠk LA08024 Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z10100523 Keywords : LIDB plasma * atmosphere * isotopes Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.053, year: 2009

  3. Investigation of laser-plasma chemistry in CO-N-2-H2O mixtures using O-18 labeled water

    Ferus, Martin; Matulková, Irena; Juha, Libor; Civiš, Svatopluk

    2009-01-01

    Roč. 472, 1-3 (2009), s. 14-18. ISSN 0009-2614 R&D Projects: GA ČR GA203/06/1278; GA MŠk LA08024; GA MŠk(CZ) LC528 Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z10100523 Keywords : carbon monoxide * plasma * atmosphere Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.291, year: 2009

  4. Key insights into the reacting kinetics of atmospheric pressure plasmas using He +N2 /O2 /CO2 /H2 O/Air mixtures

    Murakami, Tomoyuki

    2015-09-01

    A zero dimensional kinetic chemistry computational modeling to identify the important collisional mechanisms and the dominant species in atmospheric pressure plasmas has been developed. This modeling provides an enhanced capability to tailor wide variety of reactive intermediates/species in atmospheric pressure plasmas using He +N2 /O2 /CO2 /H2 O/Air mixtures. The influence of the gas constituent, the gas temperature and the excitation frequency (kHz-, RF-, Pulsed-working) on the complex reacting chemical kinetics is clarified. This work also focuses on the benchmarking between the predictive outputs of this computer-based simulations and the diverse experimental diagnostics with particular emphasis on reactive oxygen/nitrogen intermediates/species. This work was partly supported by KAKENHI Grant Number 24561054.

  5. Ca2+ pump and Ca2+/H+ antiporter in plasma membrane vesicles isolated by aqueous two-phase partitioning from corn leaves

    Plasma membrane vesicles, which are mostly right side-out, were isolated from corn leaves by aqueous two-phase partitioning method. Characteristics of Ca2+ transport were investigated after preparing inside-out vesicles by Triton X-100 treatment. 45Ca2+ transport was assayed by membrane filtration technique. Results showed that Ca2+ transport into the plasma membrane vesicles was Mg-ATP dependent. The active Ca2+ transport system had a high affinity for Ca2+(Km(Ca2+) = 0.4 microM) and ATP(Km(ATP) = 3.9 microM), and showed pH optimum at 7.5. ATP-dependent Ca2+ uptake in the plasma membrane vesicles was stimulated in the presence of Cl- or NO3-. Quenching of quinacrine fluorescence showed that these anions also induced H+ transport into the vesicles. The Ca2+ uptake stimulated by Cl- was dependent on the activity of H+ transport into the vesicles. However, carbonylcyanide m-chlorophenylhydrazone (CCCP) and VO4(3-) which is known to inhibit the H+ pump associated with the plasma membrane, canceled almost all of the Cl(-)-stimulated Ca2+ uptake. Furthermore, artificially imposed pH gradient (acid inside) caused Ca2+ uptake into the vesicles. These results suggest that the Cl(-)-stimulated Ca2+ uptake is caused by the efflux of H+ from the vesicles by the operation of Ca2+/H+ antiport system in the plasma membrane. In Cl(-)-free medium, H+ transport into the vesicles scarcely occurred and the addition of CCCP caused only a slight inhibition of the active Ca2+ uptake into the vesicles. These results suggest that two Ca2+ transport systems are operating in the plasma membrane from corn leaves, i.e., one is an ATP-dependent active Ca2+ transport system (Ca2+ pump) and the other is a Ca2+/H+ antiport system. Little difference in characteristics of Ca2+ transport was observed between the plasma membranes isolated from etiolated and green corn leaves

  6. Bandgap measurements and the peculiar splitting of E2H phonon modes of InxAl1-xN nanowires grown by plasma assisted molecular beam epitaxy

    Tangi, Malleswararao

    2016-07-26

    The dislocation free Inx Al 1-xN nanowires (NWs) are grown on Si(111) by nitrogen plasma assisted molecular beam epitaxy in the temperature regime of 490 °C–610 °C yielding In composition ranges over 0.50 ≤ x ≤ 0.17. We study the optical properties of these NWs by spectroscopic ellipsometry (SE), photoluminescence, and Raman spectroscopies since they possesses minimal strain with reduced defects comparative to the planar films. The optical bandgap measurements of Inx Al 1-xN NWs are demonstrated by SE where the absorption edges of the NW samples are evaluated irrespective of substrate transparency. A systematic Stoke shift of 0.04–0.27 eV with increasing x was observed when comparing the micro-photoluminescence spectra with the Tauc plot derived from SE. The micro-Raman spectra in the NWs with x = 0.5 showed two-mode behavior for A1(LO) phonons and single mode behavior for E2 H phonons. As for x = 0.17, i.e., high Al content, we observed a peculiar E2 H phonon mode splitting. Further, we observe composition dependent frequency shifts. The 77 to 600 K micro-Raman spectroscopy measurements show that both AlN- and InN-like modes of A1(LO) and E2 H phonons in Inx Al 1-xN NWs are redshifted with increasing temperature, similar to that of the binary III group nitride semiconductors. These studies of the optical properties of the technologically important Inx Al 1-xN nanowires will path the way towards lasers and light-emitting diodes in the wavelength of the ultra-violet and visible range.

  7. Lipon thin films grown by plasma-enhanced metalorganic chemical vapor deposition in a N{sub 2}-H{sub 2}-Ar gas mixture

    Meda, Lamartine, E-mail: LMeda@xula.edu [Department of Chemistry, Xavier University of Louisiana, 1 Drexel Drive, New Orleans, LA, 70125 (United States); Maxie, Eleston E. [Excellatron Solid State LLC, 263 Decatur Street, Atlanta, GA 30312 (United States)

    2012-01-01

    Lithium phosphorus oxynitride (Lipon) thin films have been deposited by a plasma-enhanced metalorganic chemical vapor deposition method. Lipon thin films were deposited on approximately 0.2 {mu}m thick Au-coated alumina substrates in a N{sub 2}-H{sub 2}-Ar plasma at 13.56 MHz, a power of 150 W, and at 180 Degree-Sign C using triethyl phosphate [(CH{sub 2}CH{sub 3}){sub 3}PO{sub 4}] and lithium tert-butoxide [(LiOC(CH{sub 3}){sub 3}] precursors. Lipon growth rates ranged from 10 to 42 nm/min and thicknesses varied from 1 to 2.5 {mu}m. X-ray powder diffraction showed that the films were amorphous, and X-ray photoelectron spectroscopy (XPS) revealed approximately 4 at.% N in the films. The ionic conductivity of Lipon was measured by electrochemical impedance spectroscopy to be approximately 1.02 {mu}S/cm, which is consistent with the ionic conductivity of Lipon deposited by radio frequency magnetron sputtering of Li{sub 3}PO{sub 4} targets in either mixed Ar-N{sub 2} or pure N{sub 2} atmosphere. Attempts to deposit Lipon in a N{sub 2}-O{sub 2}-Ar plasma resulted in the growth of Li{sub 3}PO{sub 4} thin films. The XPS analysis shows no C and N atom peaks. Due to the high impedance of these films, reliable conductivity measurements could not be obtained for films grown in N{sub 2}-O{sub 2}-Ar plasma.

  8. Carbon Nitride Thin Films Deposited by Plasma Assisted Nd∶YAG Laser Ablation of Graphite in N2+H2 Atmosphere

    YU Wei; WANG Shufang; ZHANG Lianshui; LI Xiaowei; FU Guangsheng

    2001-01-01

    Carbon nitride thin films are deposited on silicon wafers by 532 nm Nd∶YAG laser ablation of graphite in the N2+H2 atmosphere assisted by a dc glow discharge plasma at a higher gas pressure of about 4.0 kPa. The properties of the thin films are investigated by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) and X-ray diffraction (XRD). The results show that the deposited films are composed of α-C3N4, β-C3N4 phase and have the N/C atomic ratio of 2.01. The optical emission spectroscopy (OES) studies indicate that the introduction of a dc glow discharge and the adoption of a higher gas pressure during the film deposition are favorable to the net generation of the atomic N, CN radicals and N+2 in B2Σ+u excited state in the plasma, which are considered to play a major role in the synthesis of carbon nitride.

  9. Highly selective etching of silicon nitride to physical-vapor-deposited a-C mask in dual-frequency capacitively coupled CH2F2/H2 plasmas

    A multilevel resist (MLR) structure can be fabricated based on a very thin amorphous carbon (a-C) layer ( congruent with 80 nm) and Si3N4 hard-mask layer ( congruent with 300 nm). The authors investigated the selective etching of the Si3N4 layer using a physical-vapor-deposited (PVD) a-C mask in a dual-frequency superimposed capacitively coupled plasma etcher by varying the process parameters in the CH2F2/H2/Ar plasmas, viz., the etch gas flow ratio, high-frequency source power (PHF), and low-frequency source power (PLF). They found that under certain etch conditions they obtain infinitely high etch selectivities of the Si3N4 layers to the PVD a-C on both the blanket and patterned wafers. The etch gas flow ratio played a critical role in determining the process window for infinitely high Si3N4/PVD a-C etch selectivity because of the change in the degree of polymerization. The etch results of a patterned ArF photoresisit/bottom antireflective coating/SiOx/PVD a-C/Si3N4 MLR structure supported the idea of using a very thin PVD a-C layer as an etch-mask layer for the Si3N4 hard-mask pattern with a pattern width of congruent with 80 nm and high aspect ratio of congruent with 5.

  10. Ammonia formation in N{sub 2}/H{sub 2} plasmas on ITER-relevant plasma facing materials: Surface temperature and N{sub 2} plasma content effects

    Castro, A. de, E-mail: alfonso.decastro@ciemat.es; Alegre, D.; Tabarés, F.L.

    2015-08-15

    Ammonia production in N{sub 2}/H{sub 2} direct current glow discharge plasmas, with nitrogen concentrations from 1.5% to 33%, different wall materials (tungsten, stainless steel and aluminium as a proxy for beryllium) and surface temperatures up to 350 °C has been investigated. Ammonia yields on the exposed materials have been deduced, resulting in different values depending on the wall material, its temperature and N{sub 2} plasma content. The results indicate weak wall temperature dependence in tungsten and stainless steel. However, wall temperatures above 300 °C have a very clear influence on aluminium walls, as almost all the molecular N{sub 2} depleted from the gas phase is converted into ammonia. The amount of implanted N seems to have a direct impact on the ammonia formation yield, pointing to the competition between N implantation and N/H–N/N recombination on the walls as the key mechanism of the ammonia formation.

  11. Sex differences in glucose levels

    Faerch, K; Borch-Johnsen, Knut; Vaag, A;

    2010-01-01

    We aimed to examine whether sex differences in fasting plasma glucose (FPG), 2 h post-OGTT plasma glucose (2hPG) and HbA(1c) could be explained by differences in body size and/or body composition between men and women in a general non-diabetic Danish population. Moreover, we aimed to study to what...

  12. Quantum cascade laser investigations of CH4 and C2H2 interconversion in hydrocarbon/H2 gas mixtures during microwave plasma enhanced chemical vapor deposition of diamond

    CH4 and C2H2 molecules (and their interconversion) in hydrocarbon/rare gas/H2 gas mixtures in a microwave reactor used for plasma enhanced diamond chemical vapor deposition (CVD) have been investigated by line-of-sight infrared absorption spectroscopy in the wavenumber range of 1276.5-1273.1 cm-1 using a quantum cascade laser spectrometer. Parameters explored include process conditions [pressure, input power, source hydrocarbon, rare gas (Ar or Ne), input gas mixing ratio], height (z) above the substrate, and time (t) after addition of hydrocarbon to a pre-existing Ar/H2 plasma. The line integrated absorptions so obtained have been converted to species number densities by reference to the companion two-dimensional (r,z) modeling of the CVD reactor described in Mankelevich et al. [J. Appl. Phys. 104, 113304 (2008)]. The gas temperature distribution within the reactor ensures that the measured absorptions are dominated by CH4 and C2H2 molecules in the cool periphery of the reactor. Nonetheless, the measurements prove to be of enormous value in testing, tensioning, and confirming the model predictions. Under standard process conditions, the study confirms that all hydrocarbon source gases investigated (methane, acetylene, ethane, propyne, propane, and butane) are converted into a mixture dominated by CH4 and C2H2. The interconversion between these two species is highly dependent on the local gas temperature and the H atom number density, and thus on position within the reactor. CH4→C2H2 conversion occurs most efficiently in an annular shell around the central plasma (characterized by 1400gas2H2→CH4 is favored in the more distant regions where Tgas4→C2H2 conversion, whereas the reverse C2H2→CH4 process only requires H atoms to drive the reactions; H atoms are not consumed by the overall conversion.

  13. Surface reactivity of molybdenum thin films exposed to (Ar-N{sub 2}-H{sub 2}) expanding microwave plasma at low temperature: influence of the addition of H{sub 2} gas in the plasma

    Jauberteau, I [UMR 6638 CNRS, SPCTS, Faculte des Sciences et Techniques, F-87060 Limoges cedex (France); Jauberteau, J L [UMR 6638 CNRS, SPCTS, Faculte des Sciences et Techniques, F-87060 Limoges cedex (France); Cahoreau, M [UMR 6630 CNRS, SP2MI, UFR des Sciences, Bd3, Teleport 2, BP 179, F-86960 Futuroscope (France); Aubreton, J [UMR 6638 CNRS, SPCTS, Faculte des Sciences et Techniques, F-87060 Limoges cedex (France)

    2005-10-07

    The rapid transfer of a large amount of nitrogen into the surface layers followed by diffusion into the inner layers occurs in thin molybdenum films exposed to expanding microwave plasma using (Ar-35%N{sub 2}) and (Ar-25%N{sub 2}-30%H{sub 2}) gas mixtures. The nitrogen transfer into the surface layers nearly correlates to a Gaussian distribution law, which is explained by the formation of a large number of defects at the film surface in which nitrogen piles up before diffusing into the inner metal layers. Such an effect could be induced by the impinging energetic plasma species as ions, NH{sub x<3} radicals. The diffusion part is successfully fitted to Fick's second law by introducing diffusion coefficients of about (5-7) x 10{sup -14} cm{sup 2} s{sup -1} at 673 K. These values are lower than the diffusion coefficient calculated for a solid solution of nitrogen in molybdenum which is equal to about 4 x 10{sup -13} cm{sup 2} s{sup -1}. A surprisingly high diffusion coefficient of about 3 x 10{sup -13} cm{sup 2} s{sup -1} is found for the molybdenum film exposed to (Ar-25%N{sub 2}-30%H{sub 2}) plasma at room temperature. These results highlight the role of plasma hydrogen species on the enhancement of the metal surface reactivity and nitrogen diffusion into the inner metal layers. A modification of the morphology of the film surface exposed to hydrogen species is also seen. The values of electron densities measured in the various (Ar-N{sub 2}-H{sub 2}) gas mixtures are consistent with the formation of expanded plasma far from the centre of the discharge, apart from(Ar-30%N{sub 2}-12%H{sub 2}) where the plasma expansion is very low. At a distance of 10.5 cm from the centre of the discharge, the electron density is equal to about 1.66 x 10{sup 17} m{sup -3} and 1.16 x 10{sup 17} m{sup -3} for (Ar-25%N{sub 2}-30%H{sub 2}) and (Ar-35%N{sub 2}) gas mixtures, respectively.

  14. Quantum cascade laser investigations of CH4 and C2H2 interconversion in hydrocarbon/H2 gas mixtures during microwave plasma enhanced chemical vapor deposition of diamond

    Ma, Jie; Cheesman, Andrew; Ashfold, Michael N. R.; Hay, Kenneth G.; Wright, Stephen; Langford, Nigel; Duxbury, Geoffrey; Mankelevich, Yuri A.

    2009-08-01

    CH4 and C2H2 molecules (and their interconversion) in hydrocarbon/rare gas/H2 gas mixtures in a microwave reactor used for plasma enhanced diamond chemical vapor deposition (CVD) have been investigated by line-of-sight infrared absorption spectroscopy in the wavenumber range of 1276.5-1273.1 cm-1 using a quantum cascade laser spectrometer. Parameters explored include process conditions [pressure, input power, source hydrocarbon, rare gas (Ar or Ne), input gas mixing ratio], height (z) above the substrate, and time (t) after addition of hydrocarbon to a pre-existing Ar/H2 plasma. The line integrated absorptions so obtained have been converted to species number densities by reference to the companion two-dimensional (r ,z) modeling of the CVD reactor described in Mankelevich et al. [J. Appl. Phys. 104, 113304 (2008)]. The gas temperature distribution within the reactor ensures that the measured absorptions are dominated by CH4 and C2H2 molecules in the cool periphery of the reactor. Nonetheless, the measurements prove to be of enormous value in testing, tensioning, and confirming the model predictions. Under standard process conditions, the study confirms that all hydrocarbon source gases investigated (methane, acetylene, ethane, propyne, propane, and butane) are converted into a mixture dominated by CH4 and C2H2. The interconversion between these two species is highly dependent on the local gas temperature and the H atom number density, and thus on position within the reactor. CH4→C2H2 conversion occurs most efficiently in an annular shell around the central plasma (characterized by 14002H2→CH4 is favored in the more distant regions where Tgas<1400 K. Analysis of the multistep interconversion mechanism reveals substantial net consumption of H atoms accompanying the CH4→C2H2 conversion, whereas the reverse C2H2→CH4 process only requires H atoms to drive the reactions; H atoms are not consumed by the overall

  15. The influence of C2H2 and dust formation on the time dependence of metastable argon density in pulsed plasmas

    Stefanovic, Ilija; Sadeghi, Nader; Winter, Jörg

    2010-01-01

    Abstract Diode laser absorption at 772.38 nm is used to measure the time resolved density of Ar*(3 P 2) metastable atoms in a capacitively coupled radio-frequency (RF) discharge running in argon/acetylene mixture at 0.1 mbar. The RF power is pulsed at 100 Hz and the density of Ar*(3 P 2) atoms in the 5 ms ON time and in the afterglow are recorded. Different plasma conditions, namely: 1) pure argon, 2) argon + 7% acetylene before powder formation, 3) argon + 7% acetylene after dust particle...

  16. 空腹血糖、糖负荷后2h血糖和HbA1C对糖尿病的诊断价值%The diagnostic value of fasting plasma glucose, 2 h plasma glucose after glucose loading, and HbA1C to diabetes mellitus

    王毅方; 黄辉; 彭贵成; 杨玉; 邓仲良; 黄光宇; 杨庆东; 卢力沾; 朱浩源

    2015-01-01

    采用整群抽样的方法,对东莞市横沥镇35岁以上的6656名户籍居民进行问卷调查和身高、体重、腰围、臀围、血压测量,同时检测血脂、空腹血糖(FPG)、HbA1C及糖负荷后2h血糖(2hPG),仅单项血糖指标增高而无糖尿病症状者1周以后再次检测,分析采用FPG、2hPG、HbA1C对糖尿病的诊断价值.结果显示,第1周检测中,FPG、HbA1C、2hPG三者中一项以上增高的初诊糖尿病共有800例,其中FPG、HbA1C、2hPG增高的初诊糖尿病分别为42.0%、55.3%、67.1%;两两组合时FPG+HbA1C、FPG+2hPG、HbA1C+2hPG增高的初诊糖尿病分别为68.8%、79.8%、91.0%.第2周对仅单项指标增高而未能确诊的糖尿病人群进行复查,FPG、HbA1C、2hPG增高的重复率各为27.6%、74.3%、31.4%;最终共确诊糖尿病患者503例,其中FPG、HbA1C、2hPG确诊糖尿病各占55.7%、76.9%、69.8%,两两组合时,FPG+HbA1C、FPG+2hPG、HbA1C+2hPG确诊糖尿病各占87.3%、78.7%、96.8%.结果提示,单纯FPG、HbA1C、2hPG诊断糖尿病均存在不同程度的漏诊,两两组合可减少漏诊率.HbA1C较FPG、2hPG更适合作为诊断糖尿病的指标;HbA1C+2hPG明显优于其他两种组合.%A total of 6 656 residents aged above 35 years in Hengli,Dongguan,were included in this epidemiologic investigation.A questionnaire survey was performed.Body height,weight,waist circumference,hip circumference,and blood pressure were measured.The plasma lipid,fasting plasma glucose (FPG),HbA1C,and 2 h plasma glucose (2hPG) levels were detected.The test was repeated one week later if only one index was increased without any symptoms of diabetes mellitus.The diagnostic values of FPG,HbA1C,and 2hPG in diabetes mellitus were explored.The results showed that at the first week,800 subjects were initially diagnosed as cases of diabetes mellitus by only one of the elevated FPG,HbA1Cor 2hPG values.The rates of single elevations of FPG,HbA1C,and 2hPG were 42.0%,55.3

  17. Quantitation of methadone enantiomers in humans using stable isotope-labeled (2H3)-, (2H5)-, and (2H8)Methadone

    Nakamura, K.; Hachey, D.L.; Kreek, M.J.; Irving, C.S.; Klein, P.D.

    1982-01-01

    A new technique for simultaneous stereoselective kinetic studies of methadone enantiomers was developed using three deuterium-labeled forms of methadone and GLC-chemical-ionization mass spectrometry. A racemic mixture (1:1) of (R)-(-)-(2H5)methadone (l-form) and (S)-(R)-(2H3)methadone (d-form) was administered orally in place of a single daily dose of unlabeled (+/-)-(2H0)methadone in long-term maintenance patients. Racemic (+/-)-(2H8)methadone was used as an internal standard for the simultaneous quantitation of (2H0)-, (2H3)-, and (2H5)methadone in plasma and urine. A newly developed extraction procedure, using a short, disposable C18 reversed-phase cartridge and improved chemical-ionization procedures employing ammonia gas, resulted in significant reduction of the background impurities contributing to the ions used for isotopic abundance measurements. These improvements enabled the measurement of labeled plasma methadone levels for 120 hr following a single dose. This methodology was applied to the study of methadone kinetics in two patients; in both patients, the analgesically active l-enantiomer of the drug had a longer plasma elimination half-life and a smaller area under the plasma disappearance curve than did the inactive d-form.

  18. Quantitation of methadone enantiomers in humans using stable isotope-labeled [2H3]-, [2H5]-, and [2H8]Methadone

    A new technique for simultaneous stereoselective kinetic studies of methadone enantiomers was developed using three deuterium-labeled forms of methadone and GLC-chemical-ionization mass spectrometry. A racemic mixture (1:1) of (R)-(-)-[2H5]methadone (l-form) and (S)-(R)-[2H3]methadone (d-form) was administered orally in place of a single daily dose of unlabeled (+/-)-[2H0]methadone in long-term maintenance patients. Racemic (+/-)-[2H8]methadone was used as an internal standard for the simultaneous quantitation of [2H0]-, [2H3]-, and [2H5]methadone in plasma and urine. A newly developed extraction procedure, using a short, disposable C18 reversed-phase cartridge and improved chemical-ionization procedures employing ammonia gas, resulted in significant reduction of the background impurities contributing to the ions used for isotopic abundance measurements. These improvements enabled the measurement of labeled plasma methadone levels for 120 hr following a single dose. This methodology was applied to the study of methadone kinetics in two patients; in both patients, the analgesically active l-enantiomer of the drug had a longer plasma elimination half-life and a smaller area under the plasma disappearance curve than did the inactive d-form

  19. Syntheses of [5-2H]-uracil, [5-2H]-cytosine, [6-2H]-uracil and [6-2H]-cytosine

    Syntheses of [5-2H]-, [6-2H]-uracil and [5-2H]-, [6-2H]-cytosine were investigated. The catalytic reaction of uracil or cytosine with 2H2 gas in alkaline media gave rise to [6-2H]-compounds almost exclusively. On the other hand, the reaction of 5-bromouracil or 5-bromocytosine with 2H2 gas gave rise to a mixture of [5-2H]-, [6-2H]- and [5-2H, 6-2H]-compounds depending on the experimental conditions. By controlling the temperature, the pressure of 2H2 gas and the amount of catalyst, [5-2H]-uracil and [5-2H]-cytosine were obtained. The isotopic distribution in each product was measured by 1H NMR spectroscopy combined with an HPLC method. (author)

  20. 空腹血糖、餐后2h血糖及糖化血红蛋白对糖尿病的诊断价值%Diagnostic value of fasting plasma glucose, 2 h postprandial plasma glucose and glycosylated hemoglobin on diabetes mellitus

    陈妍; 刘建国; 徐磊; 滑劲咏; 王惠梅; 常冉; 郭春丽

    2012-01-01

    Aim:To investigate the diagnostic value of the fasting plasma glucose (FPG) ,2 h postprandial plasma glucose (2 h-PG) and glycosylated hemoglobin ( HbAlc) towards diabetes mellitus ( DM) and impaired glucose regulation (IGR). Methods: A total of 738 patients with complete clinical data were collected from December 2009 to August 2011 in the Second People's Hospital of Zhengzhou and Zhengzhou Central Hospital . All the subjects were detected for the FPG , HbAlc and 2 h-PG,while the levels of HbAlc ranging 5.4% to 7. 0% were enrolled the study. Receiver operating characteristic curve (ROC curve) was used to examine the optimal cut-point of HbAlc for detecting DM and IGR. ReSUltS; Regarding FPG≥7. 0 mmol/L and (or) 2 h-PG≥11. 1 mmol/L as the gold standard for diagnosing DM and making ROC curve,and the optimal cut-point of HbAlc for diagnosing DM was 6. 35% , with sensitivity of 0. 698 , specificity of 0. 680 , positive likelihood ratio of 2. 18 and negative likelihood ratio of 0.44. Regarding FPG 6. 1 - 6. 9 mmol/L and (or) 2 h-PG 7. 8 ~ 11. 1 mmol/L as the gold standard for diagnosing IGR and making ROC curve ,and the optimal cut-point of HbAlc was 6.0% ,with sensitivity of 0. 646, specificity of 0. 659 , positive likelihood ratio of 1.89 and negative likelihood ratio of 0.54. Conclusion:There are a medium sensitivity to diagnose DM by HbAlc and a lower sensitivity to diagnose IGR by HbAlc. Combined test may contribute to improve the detection rate of DM and IGR .%目的:探讨空腹血糖、餐后2 h血糖及糖化血红蛋白(HbAlc)对糖尿病及糖调节受损的诊断价值.方法:收集2009年12月至2011年8月在郑州市第二人民医院和郑州市中心医院检测空腹血糖(FPG)、糖化血红蛋白(HbAlc)和餐后2 h血糖(2h-PG)的738例临床资料完整的、HbAlc在5.4%~7.0%的就诊者入选该研究,采用ROC曲线确定HbAlc预测糖尿病及糖调节受损的诊断界点.结果:以FPG≥7.0 mmol/L和(或)餐后2 h-PG≥11.1 mmol/L为诊

  1. Atomic and plasma-material interaction data for fusion. V. 8. Elastic and related transport cross sections for collisions among isotopomers of H+ + H, H+ + H2, H+ + He, H + H, and H + H2

    The Volume 8 of the 'Atomic and Plasma-Material Interaction Data for Fusion' provides an exhaustive source of information on elastic scattering, momentum transfer and viscosity cross sections for collisions of hydrogenic ions, atoms and molecules, and their isotopes, in the energy range pertinent to fusion reactor divertor plasmas and extending (in its low-energy part) to collision conditions that are relevant for astrophysics. Hydrogen ion-helium atom collisions are also included. The reported cross sections are obtained from extensive quantum-mechanical calculations and can be regarded as having very high accuracy

  2. Nitriding of titanium and its alloys by N2, NH3 or mixtures of N2 + H2 in a dc arc plasma at low pressures ( or = to torr)

    Avni, R.

    1984-01-01

    The dc glow discharges in different gas mixtures of Ar + N2, Ar + NH3 or Ar + N2 + H2 result in the surface nitriding of Ti metal and its alloy (Ti6Al4V). Various gas mixtures were used in order to establish the main active species governing the nitriding process, i.e., N, N2, NH, or NH2 as excited or ionized particles. The dc discharge was sampled and analyzed by quadruple mass spectrometry (QPMS) and optical emission spectroscopy (OES), and the nitrided samples were analyzed by scanning electron microscopy (SEM) with an EDAX attachment, microhardness, and Fourier transform infrared reflectance spectrometry (FTIR). It was found that the excited and ionized nitrogen and hydrogen atoms are the main species responsible for the nitriding process in a dc glow discharge.

  3. Mecanismos cinéticos y distribuciones energéticas de iones (H3+, N2H+, CH3+...) en plasmas fríos de H2/N2/CH4

    Tanarro, I.; Herrero, V. J.; Islyaikin, A.; Tabarés, F. L.; Tafalla, D.

    En este trabajo se presenta el estudio espectrométrico de los plasmas levemente ionizados generados en una descarga continua a baja presión de H2 con trazas de N2 y CH4, orientado principalmente a identificar la naturaleza y distribución energética de los iones que en ella se producen, y a asignar algunos de los mecanismos cinéticos elementales de formación y destrucción de tales especies. Alguno de los iones mayoritarios de estos plasmas, como el H3+, presenta gran interés desde el punto de vista de la Astrofísica por su prevista intervención en la química de las ionosferas planetarias y del medio interestelar, al actuar como sustancia intermedia en la formación de gran variedad de especies moleculares; si bien, dada su pequeña concentración, su observación real en el espacio se demoró hasta la pasada década de los años 90, cuando fue detectado por primera vez en la atmósfera de Júpiter y en otros objetos estelares. Del mismo modo que los trabajos espectroscópicos de laboratorio resultan indispensables para la posterior identificación de las especies observadas en el espacio, es de esperar que la asignación de los procesos cinéticos más importantes que tienen lugar en los plasmas generados en reactores de descarga, como los aquí presentados, permitan extrapolar los resultados así obtenidos al esclarecimiento de los mecanismos fisico-químicos participantes en otros medios observables únicamente a larga distancia.

  4. Intense laser induced field ionization of C2H2, C2H4,and C2H6

    GAO Lirong; JI Na; XONG Yijia; TANG Xiaoping; KONG Fan'ao

    2003-01-01

    Using HOMO Field Ionization Model, the tunneling probabilities and the theoretical threshold intensities of the field ionizations of acetylene, ethylene, and ethane in intense laser field are calculated. C2H2, C2H4, and C2H6 were irradiated by 800 nm, 100 fs laser pulses with the intensity range of 1013-1014 W/cm2. A TOF-mass spectrometer was coupled to the laser system and used to experimentally investigate the field ionization of these molecules. The experimental ionization threshold intensities are obtained. The calculating results of the three molecules agree well with the experimental results, indicating that HOMO Field Ionization Model is valid for the ionization of polyatomic molecules in intense laser field.

  5. Synthesis of 1-C2H3 theophylline and 3-C2H3 theophylline

    This article describes a three step-selective deuteration method of 1-methyl and 3-methylxanthine, after protection of the N-7 position by chloromethylpivalate and alkylation by trideuteromethyl iodide ; yielding 1-C2H3 and 3-C2H3 theophylline. (author)

  6. Supramolecular stabilization of N(2)H(7)(+).

    Atwood, Jerry L; Barbour, Leonard J; Jerga, Agoston

    2002-03-13

    The cation N(2)H(7)(+) has been stabilized in a largely hydrophobic supramolecular environment and characterized in the solid state. The cation is situated in the bowl-shaped cavity of calix[4]arene. All of the hydrogen atoms are clearly discernible owing to high-quality X-ray data as well as lack of disorder and symmetry-imposed ambiguity. It appears that electrostatic interactions play a critical role in stabilizing the structure. PMID:11878959

  7. Dissociative recombination of N2H+

    dos Santos, S. Fonseca; Ngassam, V.; Orel, A. E.; Larson, Å.

    2016-08-01

    The direct and indirect mechanisms of dissociative recombination of N2H+ are theoretically studied. At low energies, the electron capture is found to be driven by recombination into bound Rydberg states, while at collision energies above 0.1 eV, the direct capture and dissociation along electronic resonant states becomes important. Electron-scattering calculations using the complex Kohn variational method are performed to obtain the scattering matrix as well as energy positions and autoionization widths of resonant states. Potential-energy surfaces of electronic bound states of N2H and N2H+ are computed using structure calculations with the multireference configuration interaction method. The cross section for the indirect mechanism is calculated using a vibrational frame transformation of the elements of the scattering matrix at energies just above the ionization threshold. Here vibrational excitations of the ionic core from v =0 to v =1 and v =2 for all three normal modes are considered and autoionization is neglected. The cross section for the direct dissociation along electronic resonant states is computed with wave-packet calculations using the multiconfiguration time-dependent Hartree method, where all three internal degrees of freedom are considered. The calculated cross sections are compared to measurements.

  8. Synthesis of (2R,S)-[2-2H] and [2,3-2H] tryptophan

    α-Deuterated tryptophan was prepared either by exchange of the α-hydrogen of tryptophan or by hydrolysis and decarboxylation of ethyl 2-formamido-2-carbethoxy-3-indole propionate, followed by treatment with CH3COO2H. α,β-dideuterated tryptophan was in turn synthetized from ethyl-α-acetamido-indole-3-acrylate, by catalytic deuteration (2H2/Pd-C) and alkaline hydrolysis (NaO2H/2H2O). (author)

  9. Determination of muscle protein synthesis rates in fish using (2)H2O and (2)H NMR analysis of alanine.

    Marques, Cátia; Viegas, Filipa; Rito, João; Jones, John; Viegas, Ivan

    2016-09-15

    Following administration of deuterated water ((2)H2O), the fractional synthetic rate (FSR) of a given endogenous protein can be estimated by (2)H-enrichment quantification of its alanine residues. Currently, this is measured by mass spectrometry following a derivatization procedure. Muscle FSR was measured by (1)H/(2)H NMR analysis of alanine from seabass kept for 6 days in 5% (2)H-enriched saltwater, following acid hydrolysis and amino acid isolation by cation-exchange chromatography of muscle tissue. The analysis is simple and robust, and provides precise measurements of excess alanine (2)H-enrichment in the 0.1-0.4% range from 50 mmol of alanine recovered from muscle protein. PMID:27418547

  10. The enantiospecific synthesis of [5-2H]-5-epi-shikimic acid and of (6R) [6-2H]-, (6S) [6-2H]- and [6-2H2] shikimic acid

    The enantioselective synthesis of [5-2H]-5-epi-shikimic acid starting from commercially available L-shikimic acid has been accomplished in this work. The introduction of the stable isotope was facilitated by an enzymic reduction of a ketone. An interesting stereospecific enolisation was also observed during this reaction resulting in partial deuteration of the 6-equatorial position. In addition, the enantioselective syntheses of methyl (6R) [6-2H]-, and (6S) [6-2H] shikimate are described. The procedure is an adaptation of a reported enantiospecific synthesis of shikimic acid, with the inclusion of an enzymic reduction step. (author)

  11. Theoretical Studies on N2H+O Reaction

    L(U) Ying-wen; L(U) Wen-cai; SU Zhong-min

    2008-01-01

    The N2H+O potential energy profile was studied at the CCSD(T)/6-311G++(dfp)//MP2/6-311G(d,p) level.Reactions associated with four intermediates(cis-HNNO, trans-HNNO, NNHO, and NNOH) were investigated. The results indicate that N2H+O reaction toward H+N2O is more favored than that toward N2+OH, consistent with previous experimental studies. The pathways for the two reactions are found to go through cis-HNNO, transition state, and finally to the products. The N2H+O→NH+NO reaction was studied in detail. Product NO in such a reaction is likely to occur via cis-HNNO, followed by trans-HNNO, and finally dissociates into NH+NO. These results suggest that N2H+O→NH+NO is an important channel in NO production.

  12. C2H observations toward the Orion Bar

    Nagy, Z.; Ossenkopf, V.; Van der Tak, F. F. S.; Faure, A.; Makai, Z.; Bergin, E. A.

    2015-06-01

    Context. The ethynyl radical (C2H) is one of the first radicals to be detected in the interstellar medium. Its higher rotational transitions have recently become available with the Herschel Space Observatory. Aims: We aim to constrain the physical parameters of the C2H emitting gas toward the Orion Bar. Methods: We analyze the C2H line intensities measured toward the Orion Bar CO+ Peak and Herschel/HIFI maps of C2H, CH, and HCO+ and a NANTEN map of [Ci]. We interpret the observed C2H emission using the combination of Herschel/HIFI and NANTEN data with radiative transfer and PDR models. Results: Five rotational transitions of C2H (from N = 6-5 up to N = 10-9) have been detected in the HIFI frequency range toward the CO+ peak of the Orion Bar. Based on the five detected C2H transitions, a single component rotational diagram analysis gives a rotation temperature of ~64 K and a beam-averaged C2H column density of 4 × 1013 cm-2. The rotational diagram is also consistent with a two-component fit, resulting in rotation temperatures of 43 ± 0.2 K and 123 ± 21 K and in beam-averaged column densities of ~8.3 × 1013 cm-2 and ~2.3 × 1013 cm-2 for the three lower-N and for the three higher-N transitions, respectively. The measured five rotational transitions cannot be explained by any single parameter model. According to a non-LTE model, most of the C2H column density produces the lower-N C2H transitions and traces a warm (Tkin ~ 100-150 K) and dense (n(H2) ~ 105-106 cm-3) gas. A small fraction of the C2H column density is required to reproduce the intensity of the highest-N transitions (N = 9-8 and N = 10-9) originating in a high-density (n(H2) ~5 × 106 cm-3) hot (Tkin ~ 400 K) gas. The total beam-averaged C2H column density in the model is 1014 cm-2. A comparison of the spatial distribution of C2H to those of CH, HCO+, and [Ci] shows the best correlation with CH. Conclusions: Both the non-LTE radiative transfer model and a simple PDR model representing the Orion Bar

  13. Atmospheric chemistry of CF3OCF2CF2H and CF3OC(CF3)2H

    Andersen, Mads Peter Sulbæk; Nielsen, O J; Wallington, T J;

    2005-01-01

    gives CF3OC(O)CF3 and COF2 in molar yields that are indistinguishable from 100%. Quantitative infrared spectra were recorded and used to estimate global warming potentials of 3690 and 8230 (100 year time horizon, relative to CO2) for CF3OCF2CF2H and CF3OC(CF3)2H, respectively. All experiments were...

  14. Spectroscopic measurements of the electron temperature in low pressure radiofrequency Ar/H{sub 2}/C{sub 2}H{sub 2} and Ar/H{sub 2}/CH{sub 4} plasmas used for the synthesis of nanocarbon structures

    Gordillo-Vazquez, F J [Instituto de Optica (CSIC), Serrano 121, 28006 Madrid (Spain); Camero, M [Instituto de Ciencia de Materiales de Madrid (CSIC), 28049 Madrid (Spain); Gomez-Aleixandre, C [Instituto de Ciencia de Materiales de Madrid (CSIC), 28049 Madrid (Spain)

    2006-02-15

    This paper deals with optical emission spectroscopy studies of low pressure (0.1-0.5 Torr) capacitively coupled radiofrequency hydrocarbon/argon-rich plasmas used for the synthesis of nanocarbon structures. The main goal of this paper is to obtain the electron temperature of such far-from-equilibrium plasmas as a function of the pressure, the excitation power and the argon content. In doing so, we have found that the argon upper energy levels used for electron temperature estimation remain close to corona balance. The latter has allowed us to use a modified Boltzmann plot technique to derive the electron temperature. It was found that, for the plasmas investigated, an increase of the argon population density (from 10% to 95%) leads to a pronounced decrease of the electron temperature while an increase of the processing pressure produces a moderate increase of the electron temperature. Additionally, the increase of the power from 50 to 300 W produces a very slight growth of the electron temperature.

  15. High pressure oxidation of C2H4/NO mixtures

    Giménez-López, J.; Alzueta, M.U.; Rasmussen, C.T.;

    2011-01-01

    An experimental and kinetic modeling study of the interaction between C2H4 and NO has been performed under flow reactor conditions in the intermediate temperature range (600–900K), high pressure (60bar), and for stoichiometries ranging from reducing to oxidizing conditions. The main reaction...... reaction HOCH2CH2OO+NO→CH2OH+CH2O+NO2, which pushes a complex system of partial equilibria towards products. This is a confirmation of the findings of Doughty et al. [3] for a similar system at atmospheric pressure. Under reducing conditions and temperatures above 700K, a significant fraction of the NOx is...... pathways of the C2H4/O2/NOx conversion, the capacity of C2H4 to remove NO, and the influence of the presence of NOx on the C2H4 oxidation are analyzed. Compared to the C2H4/O2 system, the presence of NOx shifts the onset of reaction 75–150K to lower temperatures. The mechanism of sensitization involves the...

  16. Alanine flux in obese and healthy humans as evaluated by 15N- and 2H3-labeled alanines

    Estimates of plasma alanine flux as measured in humans using L-[15N]-alanine or L-[3,3,3-2H3]alanine were compared by simultaneous intravenous infusion of both tracers. Plasma isotope enrichments were measured by chemical ionization gas chromatography-mass spectrometry. In 16 obese women before and during a hypocaloric diet and in 4 normal men in the postabsorptive and fed states, the fluxes were highly correlated (r2 = 0.93) although plasma alanine flux with the 2H tracer was two to three times greater than that obtained with [15N]alanine. The fluxes decreased with the hypocaloric diet in obese subjects and increased during the fed state in healthy adults. Thus, although the estimates of alanine flux differed according to the tracer used, both appear to give equivalent information about changes in alanine kinetics induced by the nutritional conditions examined

  17. N2H+ Observations of Molecular Cloud Cores in Taurus

    Tatematsu, K; Umemoto, T; Kandori, R.; Y. Sekimoto

    2004-01-01

    N2H+ observations of molecular cloud cores in Taurus with the Nobeyama 45 m radio telescope are reported. We compare ``cores with young stars'' with ``cores without young stars''. The differences in core radius, linewidth, and core mass are small. Linewidth is dominated by thermal motions in both cases. N2H+ maps show that the intensity distribution does not differ much between cores without stars and those with stars. This is in contrast to the result previously obtained in H13CO+ toward Tau...

  18. Search for the isomers of C2H3NO and C2H3NS in the Interstellar Medium

    Etim, Emmanuel; Chakrabarti, Sandip Kumar; Das, Ankan; Gorai, Prasanta; Arunan, Elangannan

    2016-07-01

    With about 40% of all the known interstellar and circumstellar molecules having their isomeric analogues as known astromolecules, isomerism remains one of the leading themes in interstellar chemistry. In this regard, the recent detection of methyl isocyanate (with a number of isomeric analogues) in the Sgr B2(N) giant molecular cloud opens a new window for the possible astronomical detection of other C_2H_3NO isomers. The present work looks at the possibility of detecting other isomers of methyl isocyanate by considering different factors such as thermodynamic stability of the different isomers with respect to the Energy, Stability and Abundance (ESA) relationship, effect of interstellar hydrogen bonding with respect to the formation these isomers on the surface of the interstellar dust grains, possible formation routes for these isomers, spectroscopic parameters for potential astromolecules among these isomers, chemical modeling among other studies. The same studies are repeated for the C_2H_3NS isomers which are the isoelectroninc analogues of the C_2H_3NO isomers taking into account the unique chemistry of S and O-containing interstellar molecular species. Among the C_2H_3NS isomers, methyl isothiocyanate remains the most potential candidate for astronomical observation.

  19. Dynamics of He2++H ionization with exponential cosine-screened Coulomb potential

    Dynamics of He2++H ionization in dense quantum plasmas (DQPs) has been studied by the classical trajectory Monte Carlo method. The interactions between charged particles have been described by the exponential cosine-screened Coulomb potential. It is found that ionization cross sections in plasma environments are obviously larger than those in plasma-free environments due to the screening effects. Cross sections for H+ also have been calculated for comparison. For H+, cross sections increase with the increase of screening effects. However, for He2+, cross sections begin to decrease in strong screening effects at intermediate energies. Furthermore, He2+ impact ionization cross sections in weakly coupled plasmas (WCPs) also have been calculated. The interactions have been described by the static screened Coulomb potential. It is found that when screening effects are weak, cross sections in DQPs and WCPs are approximately the same. As screening effects increase, cross sections in DQPs become larger than those in WCPs at high energies. However, when screening effects are strong enough, cross sections in DQPs become smaller than those in WCPs at low and intermediate energies. (paper)

  20. Synthesis and structure of [(UO2(OH)(C6NO2H4)(C6NO2H5)

    [(UO2(OH)(C6NO2H4)(C6NO2H5)] (1) monocrystals are synthesized and studied by the method of x-ray diffraction. The compound is crystallized into monoclinic lattice with parameters: space group P21/n, Z=2, a=8.789(1), b=16.635(7), c=9.238(1), β=97.89(1). Basic structural units of the crystal are chains with composition coincidental with composition of compound belonging to crystal-chemical group AM2B2M1 (A=UO22+; M2=OH-, B2 and M1 - molecules of isonicotinic acid or isonicotinate-ions) of uranyl complexes. Reciprocal packing of the chains into three-dimensional skeleton is determined by hydrogen bonds

  1. Evidence of an association between the Arg72 allele of the peptide YY and increased risk of type 2 diabetes

    Torekov, Signe S; Larsen, Lesli H; Glümer, Charlotte; Borch-Johnsen, Knut; Jørgensen, Torben; Holst, Jens J; Madsen, Ole D; Hansen, Torben; Pedersen, Oluf

    2005-01-01

    1.05-1.35]). The same polymorphism associated with overweight (25 plasma glucose level 2 h after an oral glucose...... tolerance test (OGTT) (P = 0.03), an increased area under the curve for the post-OGTT plasma glucose level (P = 0.03), and a lower insulinogenic index (P = 0.01). In conclusion, the common Arg allele of the PYY Arg72Thr variant modestly associates with type 2 diabetes and with type 2 diabetes...

  2. Hydrophobization of epoxy nanocomposite surface with 1H,1H,2H,2H-perfluorooctyltrichlorosilane for superhydrophobic properties

    Psarski, Maciej; Marczak, Jacek; Celichowski, Grzegorz; Sobieraj, Grzegorz; Gumowski, Konrad; Zhou, Feng; Liu, Weimin

    2012-10-01

    Nature inspires the design of synthetic materials with superhydrophobic properties, which can be used for applications ranging from self-cleaning surfaces to microfluidic devices. Their water repellent properties are due to hierarchical (micrometer- and nanometre-scale) surface morphological structures, either made of hydrophobic substances or hydrophobized by appropriate surface treatment. In this work, the efficiency of two surface treatment procedures, with a hydrophobic fluoropolymer, synthesized and deposited from 1H,1H,2H,2H-perfluorooctyltrichlorosilane (PFOTS) is investigated. The procedures involved reactions from the gas and liquid phases of the PFOTS/hexane solutions. The hierarchical structure is created in an epoxy nanocomposite surface, by filling the resin with alumina nanoparticles and micron-sized glass beads and subsequent sandblasting with corundum microparticles. The chemical structure of the deposited fluoropolymer was examined using XPS spectroscopy. The topography of the modified surfaces was characterized using scanning electron microscopy (SEM), and atomic force microscopy (AFM). The hydrophobic properties of the modified surfaces were investigated by water contact and sliding angles measurements. The surfaces exhibited water contact angles of above 150° for both modification procedures, however only the gas phase modification provided the non-sticking behaviour of water droplets (sliding angle of 3°). The discrepancy is attributed to extra surface roughness provided by the latter procedure.

  3. Doping dependent plasmon dispersion in 2 H -transition metal dichalcogenides

    Müller, Eric; Büchner, Bernd; Habenicht, Carsten; König, Andreas; Knupfer, Martin; Berger, Helmuth; Huotari, Simo

    2016-07-01

    We report the behavior of the charge carrier plasmon of 2 H -transition metal dichalcogenides (TMDs) as a function of intercalation with alkali metals. Intercalation and concurrent doping of the TMD layers have a substantial impact on plasmon energy and dispersion. While the plasmon energy shifts are related to the intercalation level as expected within a simple homogeneous electron gas picture, the plasmon dispersion changes in a peculiar manner independent of the intercalant and the TMD materials. Starting from a negative dispersion, the slope of the plasmon dispersion changes sign and grows monotonously upon doping. Quantitatively, the increase of this slope depends on the orbital character (4 d or 5 d ) of the conduction bands, which indicates a decisive role of band structure effects on the plasmon behavior.

  4. 2H NMR studies of supercooled and glassy aspirin

    Nath, R.; Nowaczyk, A.; Geil, B.; Bohmer, R.

    2007-11-01

    Acetyl salicylic acid, deuterated at the methyl group, was investigated using 2H-NMR in its supercooled and glassy states. Just above the glass transition temperature the molecular reorientations were studied using stimulated-echo spectroscopy and demonstrated a large degree of similarity with other glass formers. Deep in the glassy phase the NMR spectra look similar to those reported for the crystal [A. Detken, P. Focke, H. Zimmermann, U. Haeberlen, Z. Olejniczak, Z. T. Lalowicz, Z. Naturforsch. A 50 (1995) 95] and below 20 K they are indicative for rotational tunneling with a relatively large tunneling frequency. Measurements of the spin-lattice relaxation times for temperatures below 150 K reveal a broad distribution of correlation times in the glass. The dominant energy barrier characterizing the slow-down of the methyl group is significantly smaller than the well defined barrier in the crystal.

  5. Detailed Studies of Hydrocarbon Radicals: C2H Dissociation

    Wittig, Curt

    2014-10-06

    A novel experimental technique was examined whose goal was the ejection of radical species into the gas phase from a platform (film) of cold non-reactive material. The underlying principle was one of photo-initiated heat release in a stratum that lies below a layer of CO2 or a layer of amorphous solid water (ASW) and CO2. A molecular precursor to the radical species of interest is deposited near or on the film's surface, where it can be photo-dissociated. It proved unfeasible to avoid the rampant formation of fissures, as opposed to large "flakes." This led to many interesting results, but resulted in our aborting the scheme as a means of launching cold C2H radical into the gas phase. A journal article resulted that is germane to astrophysics but not combustion chemistry.

  6. 2H and 18O Freshwater Isoscapes of Scotland

    Meier-Augenstein, Wolfram; Hoogewerff, Jurian; Kemp, Helen; Frew, Danny

    2013-04-01

    Scotland's freshwater lochs and reservoirs provide a vital resource for sustaining biodiversity, agriculture, food production as well as for human consumption. Regular monitoring of freshwaters by the Scottish Environment Protection Agency (SEPA) fulfils legislative requirements with regards to water quality but new scientific methods involving stable isotope analysis present an opportunity combining these mandatory monitoring schemes with fundamental research to inform and deliver on current and nascent government policies [1] through gaining a greater understanding of Scottish waters and their importance in the context of climate change, environmental sustainability and food security. For example, 2H and 18O isoscapes of Scottish freshwater could be used to underpin research and its applications in: • Climate change - Using longitudinal changes in the characteristic isotope composition of freshwater lochs and reservoirs as proxy, isoscapes will provide a means to assess if and how changes in temperature and weather patterns might impact on precipitation patterns and amount. • Scottish branding - Location specific stable isotope signatures of Scottish freshwater have the potential to be used as a tool for provenancing and thus protecting premium Scottish produce such as Scottish beef, Scottish soft fruit and Scottish Whisky. During 2011 and 2012, with the support of SEPA more than 110 samples from freshwater lochs and reservoirs were collected from 127 different locations across Scotland including the Highlands and Islands. Here we present the results of this sampling and analysis exercise isotope analyses in form of 2H and 18O isoscapes with an unprecedented grid resolution of 26.5 × 26.5 km (or 16.4 × 16.4 miles). [1] Adaptation Framework - Adapting Our Ways: Managing Scotland's Climate Risk (2009): Scotland's Biodiversity: It's in Your Hands - A strategy for the conservation and enhancement of biodiversity in Scotland (2005); Recipe For Success - Scotland

  7. Nonempirical LCAO-MO-SCF calculations of geometric structure and force field of Be2H4 molecule and Be2H3+ ion

    Determination of equilibrium geometry, of the most general force field and frequencies of normal oscillations of Be2H4 molecule and Be2H3+ ion have been carried out. The ''Orbital 8'' programme has been used for nonempirical calculations on the basis of linear combinations of nodalless gauss functions. It is shown that flat bridge Dsub(2h) symmetry configuration is the only one of nuclei in Be2H4 molecule and linear configuration of D infinity h symmetry in Be2H3+ ion. A complete set of molecular constants of Be2H4 and Be2H3+ is obtained, which permits to carry out calculations of thermodynamical functions of these compounds by the methods of statistical physics

  8. Ab initio study of {sup 2}H(d,{gamma}){sup 4}He, {sup 2}H(d,p){sup 3}H, and {sup 2}H(d,n){sup 4}He reactions and the tensor force

    Arai, K.; Aoyama, S.; Suzuki, Y.; Descouvemont, P.; Baye, D. [Division of General Education, Nagaoka National College of Technology, 888 Nishikatakai, Nagaoka, Niigata, 940-8532 (Japan); Center for Academic Information Service, Niigata University, Niigata 950-2181 (Japan); Department of Physics, Niigata University, Niigata 950-2181, Japan and RIKEN Nishina Center, Wako 351-0198 (Japan); Physique Nucleaire Theorique et Physique Mathematique, C.P.229, Universite Libre de Bruxelles, B 1050 Brussels (Belgium); Physique Quantique, CP165/82, Universite Libre de Bruxelles, B-1050 Brussels (Belgium)

    2012-11-12

    The {sup 2}H(d,p){sup 3}H, {sup 2}H(d,n){sup 3}He, and {sup 2}H(d,{gamma}){sup 4}He reactions at low energies are studied with realistic nucleon-nucleon interactions in an ab initio approach. The obtained astrophysical S-factors are all in very good agreement with experiment. The most important channels for both transfer and radiative capture are all found to dominate thanks to the tensor force.

  9. The Distribution of Synaptotagmin Ⅱ in RBL-2H3 and Its Regulation on Exocytosis of Lysosomes in RBL-2H3

    Jicheng Zhang; Jianmin Wu; Shixiu Pan; Wenli Lv

    2005-01-01

    Synaptotagmin (Syt) constitutes a family of membrane-trafficking proteins, so far nearly 20 Syts have been discovered. Extensive work showed that synatotagmins were a potential Ca2+ sensor for regulated exocytosis. This study was to investigate the expression and location of synaptotagmin Ⅱ (Syt2) in RBL-2H3 (RBL) and its role in regulating exocytosis of RBL. The expression of Syt2 in RBL was confirmed by Western blot. The recombinant expression vector pEGFP-N1-Syt2 was constructed and transfected into RBL by electroporation, the stable transfectant RBL-Syt2-S expressing fusion protein Syt2-EGFP were obtained and Syt2 was highly concentrated at plasma membrane with little detected in cytoplasm. To analyze the role of Syt2 during exocytosis of RBL, the release of cathepsin D was assayed by immunoblotting. Compared with control, the release of cathepsin D by RBL-Syt2-S was markedly decreased. The results indicated that Syt2 played a negative regulation in exocytosis of lysosomes in RBL.

  10. Human organic cation transporter 2 (hOCT2): Inhibitor studies using S2-hOCT2 cells

    Highly expressed in kidney and located on the basolateral membrane, human organic cation transporter 2 (hOCT2) can transport various compounds (i.e. drugs and toxins) into the proximal tubular cell. Using cultured proximal tubule cells stably expressing hOCT2 (i.e. S2-hOCT2 cells), we sought to probe different compound classes (e.g. analgesics, anti-depressants, anti-psychotics, disinfectant, herbicides, insecticides, local anesthetic, muscarinic acetylcholine receptor antagonist, sedatives, steroid hormone, stimulants and toxins) for their ability to inhibit 14C-TEA uptake, a prototypical OCT2 substrate. Aconitine, amitriptyline, atropine, chlorpyrifos, diazepam, fenitrothion, haloperidol, lidocaine, malathion, mianserin, nicotine and triazolam significantly inhibited 14C-TEA uptake; IC50 values were 59.2, 2.4, 2.0, 20.7, 32.3, 13.2, 32.5, 104.6, 71.1, 17.7, 52.8 and 65.5 μM, respectively. In addition, aconitine, amitriptyline, atropine, chlorpyrifos, fenitrothion, haloperidol, lidocaine, and nicotine displayed competitive inhibition with Ki values of 145.6, 2.5, 2.4, 24.8, 16.9, 51.6, 86.8 and 57.7 μM, respectively. These in vitro data support the notion that compounds pertaining to a wide variety of different drug classes have the potential to decrease renal clearance of drugs transported via hOCT2. Consequently, these data warrant additional studies to probe hOCT2 and its role to influence drug pharmacokinetics

  11. Temperature dependence of third order ion molecule reactions. The reaction H+3 + 2H2 = H+5 + H2

    The rate constants k1 for Reaction (1): H+3+2H2 = H+5+H2 were measured in the temperature range 100--300 degreeK. The temperature dependence of k1 has the form k1proportionalT-/subn/, where n=2.3. Pierce and Porter have reported a much stronger negative temperature dependence with n=4.6. The difference arises from a determination of k1 at 300 degreeK obtained by Arifov and used by Porter. The present k1 (300 degreeK) =9times10-30 (cm6 molecules-2center-dotsec-1). This is more than an order of magnitude larger than the Arifov value. The temperature dependence of third body dependent association reactions like (1) is examined on the basis of the energy transfer theory and the recently proposed trimolecular complex transition state theory by Meot-Ner, Solomon, Field, and Gershinowitz. The temperature dependence of the rate constant for the reverse reaction (-1) is obtained from k1 and the previously determined temperature dependence of the equilibria (1). k/sub -//sub 1/ gives a good straight line Arrhenius plot leading to k/sub -//sub 1/ =8.7times10-6 exp(-8.4/RT) cm3 molecules-1center-dotsec-1. The activation energy is in kcal/mole. The preexponential factor is much larger than the rate constant for Langevin collisions. This is typical for pyrolysis of ions involving second order activation

  12. Simulation of nanoparticle coagulation in radio-frequency capacitively coupled C2H2 discharges

    A self-consistent fluid model is employed to investigate the coagulation stage of nanoparticle formation, growth, charging, and transport in a radio-frequency capacitively coupled parallel-plate acetylene (C2H2) discharge. In our simulation, the distribution of neutral species across the electrode gap is determined by mass continuity, momentum balance, and energy balance equations. Since a thermal gradient in the gas temperature induced by the flow of the neutral gas, a careful study of the thermophoretic force on the spatial distribution of the nanoparticle density profiles is indispensable. In the present paper, we mainly focus on the influences of the gas flow rate, voltage, and gas pressure on the spatial distribution of the nanoparticle density. It appears that the resulting density profile of the 10-nm particles experiences a significant shift towards the upper showerhead electrode once the neutral equations are applied, and a serious shift is observed when increasing the gas flow rate. Thus, the flow of neutral gas can strongly influence the spatial distribution of the particles in the plasma. (physics of gases, plasmas, and electric discharges)

  13. Full-dimensional quantum dynamics study of the H2 + C2H → H + C2H2 reaction on an ab initio potential energy surface.

    Chen, Liuyang; Shao, Kejie; Chen, Jun; Yang, Minghui; Zhang, Dong H

    2016-05-21

    This work performs a time-dependent wavepacket study of the H2 + C2H → H + C2H2 reaction on a new ab initio potential energy surface (PES). The PES is constructed using neural network method based on 68 478 geometries with energies calculated at UCCSD(T)-F12a/aug-cc-pVTZ level and covers H2 + C2H↔H + C2H2, H + C2H2 → HCCH2, and HCCH2 radial isomerization reaction regions. The reaction dynamics of H2 + C2H → H + C2H2 are investigated using full-dimensional quantum dynamics method. The initial-state selected reaction probabilities are calculated for reactants in eight vibrational states. The calculated results showed that the H2 vibrational excitation predominantly enhances the reactivity while the excitation of bending mode of C2H slightly inhibits the reaction. The excitations of two stretching modes of C2H molecule have negligible effect on the reactivity. The integral cross section is calculated with J-shift approximation and the mode selectivity in this reaction is discussed. The rate constants over 200-2000 K are calculated and agree well with the experimental measured values. PMID:27208951

  14. Microdomains of High Calcium Are Not Required for Exocytosis in Rbl-2h3 Mucosal Mast Cells

    Mahmoud, Sahar F.; Fewtrell, Clare

    2001-01-01

    We have previously shown that store-associated microdomains of high Ca2+ are not essential for exocytosis in RBL-2H3 mucosal mast cells. We have now examined whether Ca2+ microdomains near the plasma membrane are required, by comparing the secretory responses seen when Ca2+ influx was elicited by two very different mechanisms. In the first, antigen was used to activate the Ca2+ release–activated Ca2+ (CRAC) current (ICRAC) through CRAC channels. In the second, a Ca2+ ionophore was used to tra...

  15. Bonding in Zintl phase hydrides: density functional calculations for SrAlSiH, SrAl2H2, SrGa2H2 and BaGa2H2

    Subedi, Alaska P [ORNL; Singh, David J [ORNL

    2008-01-01

    We investigate the bonding characteristics of SrAlSiH, SrAl{sub 2}H{sub 2}, SrGa{sub 2}H{sub 2}, and BaGa{sub 2}H{sub 2} using density functional calculations. The mixed bonding characteristic of other families of Zintl phases is found, with the formation of covalent sp{sup 2} bonds in the Al/Ga/Al-Si planes of the various compounds. On the other hand the Sr and Ba atoms occur as divalent cations, while the H is anionic. The results indicate that insulating SrSiAlH may be a switchable ferroelectric.

  16. 2H and 13C tracer studies of ethanol metabolism by Fourier transform 13C[2H, 1H] NMR difference spectroscopy

    A novel form of NMR difference spectroscopy has been developed to monitor low levels of deuterium incorporation in steroids resulting from ethanol metabolism. Ethanol specifically labeled with 13C and/or 2H was administered to bile fistula rats, and bile acids were collected, derivatized and separated. Subtracting 13C [1H] spectra from 13C[2H,1H] spectra of such samples, where the brackets imply complete noise decoupling of the indicated nuclei, results in difference spectra. These spectra display 13C resonances only from 13C spins which are J-coupled to 2H spins. Particular sites and extents of 2H incorporation along the steroid skeletons could thus be evaluated and compared with GC-MS analysis. A practical lower limit of approximately 20 nanomoles of 13C--2H couples could be observed using this technique, through use of sample microcells, quadrature detection and long-term signal averaging

  17. Electron swarm parameters in pure C2H2 and in C2H2-Ar mixtures and electron collision cross sections for the C2H2 molecule

    Nakamura, Yoshiharu

    2010-09-01

    Electron swarm parameters (the drift velocity and the longitudinal diffusion coefficient) were measured in pure C2H2 and also in C2H2-Ar mixtures containing 0.517% and 5.06% acetylene over wide E/N ranges. These swarm parameters were analysed using a Boltzmann equation analysis and a set of electron collision cross sections for the C2H2 molecule was derived so that it was consistent with the present swarm data and published ionization coefficient. The present result suggested the presence of a Ramsauer-Townsend minimum in the elastic momentum transfer cross section at 0.08 eV and prominent threshold and resonance peaks in the ν4/ν5 vibrational excitation cross section. The present cross section set was also confirmed to be consistent with the published experimental total cross section of C2H2.

  18. Central nervous system dysfunction in a mouse model of FA2H deficiency.

    Potter, Kathleen A; Kern, Michael J; Fullbright, George; Bielawski, Jacek; Scherer, Steven S; Yum, Sabrina W; Li, Jian J; Cheng, Hua; Han, Xianlin; Venkata, Jagadish Kummetha; Khan, P Akbar Ali; Rohrer, Bärbel; Hama, Hiroko

    2011-07-01

    Fatty acid 2-hydroxylase (FA2H) is responsible for the synthesis of myelin galactolipids containing hydroxy fatty acid (hFA) as the N-acyl chain. Mutations in the FA2H gene cause leukodystrophy, spastic paraplegia, and neurodegeneration with brain iron accumulation. Using the Cre-lox system, we developed two types of mouse mutants, Fa2h(-/-) mice (Fa2h deleted in all cells by germline deletion) and Fa2h(flox/flox) Cnp1-Cre mice (Fa2h deleted only in oligodendrocytes and Schwann cells). We found significant demyelination, profound axonal loss, and abnormally enlarged axons in the CNS of Fa2h(-/-) mice at 12 months of age, while structure and function of peripheral nerves were largely unaffected. Fa2h(-/-) mice also exhibited histological and functional disruption in the cerebellum at 12 months of age. In a time course study, significant deterioration of cerebellar function was first detected at 7 months of age. Further behavioral assessments in water T-maze and Morris water maze tasks revealed significant deficits in spatial learning and memory at 4 months of age. These data suggest that various regions of the CNS are functionally compromised in young adult Fa2h(-/-) mice. The cerebellar deficits in 12-month-old Fa2h(flox/flox) Cnp1-Cre mice were indistinguishable from Fa2h(-/-) mice, indicating that these phenotypes likely stem from the lack of myelin hFA-galactolipids. In contrast, Fa2h(flox/flox) Cnp1-Cre mice did not show reduced performance in water maze tasks, indicating that oligodendrocytes are not involved in the learning and memory deficits found in Fa2h(-/-) mice. These findings provide the first evidence that FA2H has an important function outside of oligodendrocytes in the CNS. PMID:21491498

  19. Environmental, trophic, and ecological factors influencing bone collagen δ2H

    Topalov, Katarina; Schimmelmann, Arndt; David Polly, P.; Sauer, Peter E.; Lowry, Mark

    2013-06-01

    Organic deuterium/hydrogen stable isotope ratios (i.e., 2H/1H, expressed as δ2H value in ‰) in animal tissues are related to the 2H/1H in diet and ingested water. Bone collagen preserves the biochemical 2H/1H isotopic signal in the δ2H value of collagen's non-exchangeable hydrogen. Therefore, δ2H preserved in bone collagen has the potential to constrain environmental and trophic conditions, which is of interest to researchers studying of both living and fossil vertebrates. Our data examine the relationship of δ2H values of collagen with geographic variation in δ2H of meteoric waters, with local variations in the ecology and trophic level of species, and with the transition from mother's milk to adult diet. Based on 97 individuals from 22 marine and terrestrial vertebrates (predominately mammals), we found the relationships of collagen δ2H to both geographic variation in meteoric water δ2H (R2 = 0.55) and to δ15N in bone collagen (R2 = 0.17) statistically significant but weaker than previously reported. The second strongest control on collagen δ2H in our data is dietary, with nearly 50 percent of the variance in δ2H explained by trophic level (R2 = 0.47). Trophic level effects potentially confound the local meteoric signal if not held constant: herbivores tend to have the lowest δ2H values, omnivores have intermediate ones, and carnivores have the highest values. Body size (most likely related to mass-specific metabolic rates) has a strong influence on collagen δ2H (R2 = 0.30), by causing greater sensitivity in smaller animals to seasonal climate variations and/or high evapotranspiration leading to 2H-enrichment in tissues. In marine mammals weaning produces a dramatic effect on collagen δ2H with adult values being universally higher than pup values (R2 = 0.79). Interestingly, the shift in δ15N at weaning is downward, even though normally hydrogen and nitrogen isotope ratios are positively correlated with one another in respect to trophic level. Our

  20. Transport coefficients for carbon, hydrogen, and the organic mixture C2H3

    Electrical and thermal transport coefficients are calculated for amorphous elemental carbon and hydrogen, using the best available systematic theoretical methods. The density range considered is 10-3g/cm3 less than or equal to rho less than or equal to 106g/cm3 for carbon, and 10-4g/cm3 less than or equal to rho less than or equal to 105g/cm3 for hydrogen. The temperature range considered is 10-2eV less than or equal to kT less than or equal to 104eV. Calculational methods include relativistic partial-wave analysis of the extended Ziman theory, and nonrelativistic plane-wave analysis (Born approximation) of the original Ziman theory. Physical models include relativistic Dirac-Fock-Slater and nonrelativistic Thomas-Fermi-Dirac electron-ion potentials, and one-component-plasma ion-ion structure factors. A mixing algorithm is used to obtain approximate transport coefficients for the atomic ratio C2H3. 10 refs., 31 figs

  1. Sepsis does not alter red blood cell glucose metabolism or Na+ concentration: A 2H-, 23Na-NMR study

    The effects of sepsis on intracellular Na+ concentration ([Na+]i) and glucose metabolism were examined in rat red blood cells (RBCs) by using 23Na- and 2H-nuclear magnetic resonance (NMR) spectroscopy. Sepsis was induced in 15 halothane-anesthetized female Sprague-Dawley rats by using the cecal ligation and perforation technique; 14 control rats underwent cecal manipulation without ligation. The animals were fasted for 36 h, but allowed free access to water. At 36 h postsurgery, RBCs were examined by 23Na-NMR by using dysprosium tripolyphosphate as a chemical shift reagent. Human RBCs from 17 critically ill nonseptic patients and from 7 patients who were diagnosed as septic were also examined for [Na+]i. Five rat RBC specimens had [Na+]i determined by both 23Na-NMR and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). For glucose metabolism studies, RBCs from septic and control rats were suspended in modified Krebs-Henseleit buffer containing [6,6-2H2]glucose and examined by 2H-NMR. No significant differences in [Na+]i or glucose utilization were found in RBCs from control or septic rats. There were no differences in [Na+]i in the two groups of patients. The [Na+]i determined by NMR spectroscopy agreed closely with measurements using ICP-AES and establish that 100% of the [Na+]i of the RBC is visible by NMR. Glucose measurements determined by 2H-NMR correlated closely (correlation coefficient = 0.93) with enzymatic analysis. These studies showed no evidence that sepsis disturbed RBC membrane function or metabolism

  2. The role of isovalency in the reactions of the cyano (CN), boron monoxide (BO), silicon nitride (SiN), and ethynyl (C2H) radicals with unsaturated hydrocarbons acetylene (C2H2) and ethylene (C2H4).

    Parker, D S N; Mebel, A M; Kaiser, R I

    2014-04-21

    The classification of chemical reactions based on shared characteristics is at the heart of the chemical sciences, and is well exemplified by Langmuir's concept of isovalency, in which 'two molecular entities with the same number of valence electrons have similar chemistries'. Within this account we further investigate the ramifications of the isovalency of four radicals with the same X(2)Σ(+) electronic structure - cyano (CN), boron monoxide (BO), silicon nitride (SiN), and ethynyl (C2H), and their reactions with simple prototype hydrocarbons acetylene (C2H2) and ethylene (C2H4). The fact that these four reactants own the same X(2)Σ(+) electronic ground state should dictate the outcome of their reactions with prototypical hydrocarbons holding a carbon-carbon triple and double bond. However, we find that other factors come into play, namely, atomic radii, bonding orbital overlaps, and preferential location of the radical site. These doublet radical reactions with simple hydrocarbons play significant roles in extreme environments such as the interstellar medium and planetary atmospheres (CN, SiN and C2H), and combustion flames (C2H, BO). PMID:24418936

  3. Experimental studies of collisions of excited Li(4p) atoms with C2H4, C2H6, C3H8 and theoretical interpretation of the Li-C2H4 system

    Collisions of excited Li(4p) states with C2H4, C2H6 and C3H8 are studied experimentally using far-wing scattering state spectroscopy techniques. High-level ab initio quantum mechanical studies of the Li-C2H4 system are conducted to explain the results of the experiment for this system. The recent and present works indicate that knowledge of the internal structure of the perturber (C2H4, C2H6 and C3H8) is essential to fully understand the interaction between the metal and the hydrocarbon molecules. The ab initio calculation shows that the Li(4d) (with little probability under the experimental conditions) and the Li(4p) can be formed directly through the laser pumping. It also shows that the Li(4s) and Li(3d) states can be formed through an electronic diabatic coupling involving a radiationless process. However, the Li(3p), Li(3s) and Li(2p) states can only be formed through a secondary diabatic coupling which is a much less probable process than the primary one. The calculation limited to two C2v sections of the potential energy surfaces (PESs) shows peculiar multi-state crossings that we have never seen in other lithium complexes we studied

  4. Structure, phase transitions, dielectric and spectroscopic studies of the 2-aminopyrimidinium salts: [(2-NH 2C 4N 2H 3) 2H][ClO 4] and [2-NH 2C 4N 2H 4][BF 4

    Czupiński, O.; Wojtaś, M.; Ciunik, Z.; Jakubas, R.

    2006-01-01

    Crystal structure of the 2-aminopyrimidinium derivatives: [(2-NH 2C 4N 2H 3) 2H][ClO 4] (I) and [2-NH 2C 4N 2H 4][BF 4] (II) has been determined at 100 K (I) and 293 K (II) by means of single crystal X-ray diffraction as monoclinic space group, P2/c and P2/n, respectively. The asymmetric part of the unit cell of (I) contains two symmetry independent 2-aminopyrimidine forming one dimeric cation and one disordered perchlorate anion. The structure of (II) consists of 2-aminopyrimidinium cation, [2-NH 2C 4N 2H 4] +, protonated at a pyrimidine ring-N atom and [BF 4] - anion. Differential scanning calorimetry (DSC) on perchlorate derivative ( 1:1), [2-NH 2C 4N 2H 3][ClO 4] (III)—being isomorphic to tetrafluoroborate one (I) at room temperature, reveals two phase transitions of first order: at 250/275 K and 390/410 K (cooling-heating, respectively), whereas the analog (II) only one transition at high temperatures—343/385 K. The dielectric studies in the frequency range 75 kHz - 10 MHz disclose relaxation process at high temperatures in salt (I). Infrared spectra of polycrystalline [2-NH 2C 4N 2H 4][BF 4] have been studied in the temperature range 300-420 K. Substantial changes in the temperature evolution of frequencies of internal modes of the 2-aminopyrimidinium cations and [BF 4] - anions near 390 K are due to the variations in the motion of both moieties and hydrogen bond configuration. The experimental studies indicate that all phase transitions taking place in studied 2-aminopyrimidinium derivatives are classified as an order-disorder.

  5. The evaluation of 2H(n,2n)1H reaction cross section

    2H(n,2n)p reaction cross section is useful to nuclear power development. All the experimental data of 2H(n,2n)p reaction until 1990 were collected. The original data and errors of all the experiments were analysed and fitted on computer MICRO-VAX-II with orthogonal polynomial. The recommended 2H(n,2n) cross section are presented

  6. Dissection and cytological mapping of barley chromosome 2H in the genetic background of common wheat

    Joshi, Giri Prasad; Nasuda, Shuhei; Endo, Takashi R.

    2011-01-01

    We used gametocidal (Gc) chromosomes 2C and 3C[SAT] to dissect barley 2H added to common wheat. The Gc chromosome induces chromosomal breakage resulting in chromosomal aberrations in the progeny of the 2H addition line of common wheat carrying the monosomic Gc chromosome. We conducted in situ hybridization to select plants carrying structurally rearranged aberrant 2H chromosomes and characterized them by sequential C-banding and in situ hybridization. We established 66 dissection lines of com...

  7. Synthesis of 2-substituted 2H-chromenes using potassium vinyltrifluoroborates

    Liu, Fei; Evans, Todd; Das, Bhaskar C.

    2008-01-01

    2H-Chromenes were synthesized from salicylaldehyde using potassium vinylic borates in the presence of secondary amines. We synthesized these 2H-chromene derivatives as a part of an ongoing project to develop inhibitors for TGF-β receptors. Potassium vinyl trifluoroborates react with salicylaldehydes at 80 °C in the presence of a secondary amine and produced 2-substituted 2H-chromene derivatives with a 70–90% yield.

  8. On the Meshing Efficiency of 2K-2H Type Planetary Gear Reducer

    Long-Chang Hsieh; Hsiu-Chen Tang

    2013-01-01

    This paper proposes 2K-2H type planetary gear reducer and analyzes its meshing efficiency. First, according to the concept of train value equation, the kinematic design of 2K-2H type planetary gear reducers is carried out. Three 2K-2H type planetary gear reducers are designed to illustrate the design algorithm. Then, based on the latent power theorem, the meshing efficiency equation of 2K-2H type planetary gear reducer is derived. According to the meshing efficiency equation, the meshing effi...

  9. Nuclear reaction analysis of 1H and 2H in hafnium silicate films on Si

    The 1H(15N,αγ)12C and 2H(3He,p)4He nuclear reactions were employed to detect, respectively, 1H and 2H in hafnium silicates films on Si. The methods employed to achieve quantitative analyses are described. Moreover, by performing annealing sequences in vacuum or O2 followed by 1H2 or 2H2, it was observed that the O2-preanneled films incorporate less H, either 1H or 2H. This was explained by O-deficient, H-trapping sites that are eliminated by the O2 preannealing

  10. Central nervous system dysfunction in a mouse model of FA2H deficiency

    Potter, Kathleen A.; Kern, Michael J.; Fullbright, George; Bielawski, Jacek; Scherer, Steven S.; Yum, Sabrina W.; Li, Jian J.; Cheng, Hua; Han, Xianlin; Venkata, Jagadish Kummetha; Khan, P. Akbar Ali; Rohrer, Bärbel; Hama, Hiroko

    2011-01-01

    Fatty acid 2-hydroxylase (FA2H) is responsible for the synthesis of myelin galactolipids containing hydroxy fatty acid (hFA) as the N-acyl chain. Mutations in the FA2H gene cause leukodystrophy, spastic paraplegia, and neurodegeneration with brain iron accumulation. Using the Cre-lox system, we developed two types of mouse mutants, Fa2h−/− mice (Fa2h deleted in all cells by germline deletion) and Fa2hflox/flox Cnp1-Cre mice (Fa2h deleted only in oligodendrocytes and Schwann cells). We found s...

  11. Calculational and Experimental Investigations of the Pressure Effects on Radical - Radical Cross Combinations Reactions: C2H5 + C2H3

    Fahr, Askar; Halpern, Joshua B.; Tardy, Dwight C.

    2007-01-01

    Pressure-dependent product yields have been experimentally determined for the cross-radical reaction C2H5 + C2H3. These results have been extended by calculations. It is shown that the chemically activated combination adduct, 1-C4H8*, is either stabilized by bimolecular collisions or subject to a variety of unimolecular reactions including cyclizations and decompositions. Therefore the "apparent" combination/disproportionation ratio exhibits a complex pressure dependence. The experimental studies were performed at 298 K and at selected pressures between about 4 Torr (0.5 kPa) and 760 Torr (101 kPa). Ethyl and vinyl radicals were simultaneously produced by 193 nm excimer laser photolysis of C2H5COC2H3 or photolysis of C2H3Br and C2H5COC2H5. Gas chromatograph/mass spectrometry/flame ionization detection (GC/MS/FID) were used to identify and quantify the final reaction products. The major combination reactions at pressures between 500 (66.5 kPa) and 760 Torr are (1c) C2H5 + C2H3 yields 1-butene, (2c) C2H5 + C2H5 yields n-butane, and (3c) C2H3 + C2H3 yields 1,3-butadiene. The major products of the disproportionation reactions are ethane, ethylene, and acetylene. At moderate and lower pressures, secondary products, including propene, propane, isobutene, 2-butene (cis and trans), 1-pentene, 1,4-pentadiene, and 1,5-hexadiene are also observed. Two isomers of C4H6, cyclobutene and/or 1,2-butadiene, were also among the likely products. The pressure-dependent yield of the cross-combination product, 1-butene, was compared to the yield of n-butane, the combination product of reaction (2c), which was found to be independent of pressure over the range of this study. The [ 1-C4H8]/[C4H10] ratio was reduced from approx.1.2 at 760 Torr (101 kPa) to approx.0.5 at 100 Torr (13.3 kPa) and approx.0.1 at pressures lower than about 5 Torr (approx.0.7 kPa). Electronic structure and RRKM calculations were used to simulate both unimolecular and bimolecular processes. The relative importance

  12. Hyperfine excitation of N$_2$H$^+$ by H$_2$: Toward a revision of N$_2$H$^+$ abundance in cold molecular clouds

    Lique, François; Pagani, Laurent; Feautrier, Nicole

    2014-01-01

    The modelling of emission spectra of molecules seen in interstellar clouds requires the knowledge of collisional rate coefficients. Among the commonly observed species, N$_2$H$^+$ is of particular interest since it was shown to be a good probe of the physical conditions of cold molecular clouds. Thus, we have calculated hyperfine-structure resolved excitation rate coefficients of N$_2$H$^+$(X$^1\\Sigma^+$) by H$_2(j=0)$, the most abundant collisional partner in the cold interstellar medium. The calculations are based on a new potential energy surface, obtained from highly correlated {\\it ab initio} calculations. State-to-state rate coefficients between the first hyperfine levels were calculated, for temperatures ranging from 5 K to 70 K. By comparison with previously published N$_2$H$^+$-He rate coefficients, we found significant differences which cannot be reproduced by a simple scaling relationship. As a first application, we also performed radiative transfer calculations, for physical conditions typical of ...

  13. C2H as a PDR tracer: a case study toward the Orion Bar

    Nagy, Z; Van der Tak, F F S; Faure, A; Makai, Z; Bergin, E A

    2014-01-01

    We study the spatial distribution and abundance of C2H in the prototypical high UV-illumination PDR, the Orion Bar. We analyse Herschel/HIFI maps of C2H, CH, and HCO+, and a NANTEN map of [CI]. We interpret the observed C2H emission using the combination of Herschel/HIFI and NANTEN data with radiative transfer and PDR models. Five rotational transitions of C2H (from N=6-5 up to N=10-9) have been detected in the HIFI frequency range toward the CO+ peak of the Orion Bar. Based on the five detected C2H transitions, a rotation diagram analysis gives a rotation temperature of 67 K and a C2H column density of 5x10^13 cm^-2. A non-LTE radiative transfer model with a C2H column density of 10^14 cm^-2, an H2 volume density of 10^6 cm^-3, a kinetic temperature of 400 K, and an electron density of 10 cm^-3 is required to fit the two highest rotational transitions of C2H. This model gives a reasonable fit to the lower-N transitions as well, however, the N=6-5,...,8-7 transitions are more consistent with lower kinetic tem...

  14. Structural, elastic and electronic properties of 2H- and 4H-SiC

    Md. Nuruzzaman

    2015-05-01

    Full Text Available The structural, five different elastic constants and electronic properties of 2H- and 4H-Silicon carbide (SiC are investigated by using density functional theory (DFT. The total energies of primitive cells of 2H- and 4H-SiC phases are close to each other and moreover satisfy the condition E2H >E4H . Thus, the 4H-SiC structure appears to be more stable than the 2H- one. The analysis of elastic properties also indicates that the 4H-SiC polytype is stiffer than the 2H structures. The electronic energy bands, the total density of states (DOS are calculated. The fully relaxed and isotropic bulk modulus is also estimated. The implication of the comparison of our results with the existing experimental and theoretical studies is made.

  15. The transcriptional regulator c2h2 accelerates mushroom formation in Agaricus bisporus.

    Pelkmans, Jordi F; Vos, Aurin M; Scholtmeijer, Karin; Hendrix, Ed; Baars, Johan J P; Gehrmann, Thies; Reinders, Marcel J T; Lugones, Luis G; Wösten, Han A B

    2016-08-01

    The Cys2His2 zinc finger protein gene c2h2 of Schizophyllum commune is involved in mushroom formation. Its inactivation results in a strain that is arrested at the stage of aggregate formation. In this study, the c2h2 orthologue of Agaricus bisporus was over-expressed in this white button mushroom forming basidiomycete using Agrobacterium-mediated transformation. Morphology, cap expansion rate, and total number and biomass of mushrooms were not affected by over-expression of c2h2. However, yield per day of the c2h2 over-expression strains peaked 1 day earlier. These data and expression analysis indicate that C2H2 impacts timing of mushroom formation at an early stage of development, making its encoding gene a target for breeding of commercial mushroom strains. PMID:27207144

  16. Hot-Pressing Effects on Polymer Electrolyte Membrane Investigated by 2H NMR Spectroscopy

    The structural change of Nafion polymer electrolyte membrane (PEM) induced by hot-pressing, which is one of the representative procedures for preparing membrane-electrode-assembly for low temperature fuel cells, was investigated by 2H nuclear magnetic resonance (NMR) spectroscopy. The hydrophilic channels were asymmetrically flattened and more aligned in the membrane plane than along the hot-pressing direction. The average O-2H director of 2H2O in polymer electrolyte membrane was employed to extract the structural information from the 2H NMR peak splitting data. The dependence of 2H NMR data on water contents was systematically analyzed for the first time. The approach presented here can be used to understand the chemicals' behavior in nano-spaces, especially those reshaping and functioning interactively with the chemicals in the wet and/or mixed state

  17. Hydrogen bridging in the compounds X2H (X=Al,Si,P,S)

    Owens, Zachary T.; Larkin, Joseph D.; Schaefer, Henry F.

    2006-10-01

    X2H hydrides (X =Al, Si, P, and S) have been investigated using coupled cluster theory with single, double, and triple excitations, the latter incorporated as a perturbative correction [CCSD(T)]. These were performed utilizing a series of correlation-consistent basis sets augmented with diffuse functions (aug-cc-pVXZ, X =D, T, and Q). Al2H and Si2H are determined to have H-bridged C2v structures in their ground states: the Al2H ground state is of B12 symmetry with an Al-H-Al angle of 87.6°, and the Si2H ground state is of A12 symmetry with a Si-H-Si angle of 79.8°. However, P2H and S2H have nonbridged, bent Cs structures: the P2H ground state is of A'2 symmetry with a P-P-H angle of 97.0°, and the S2H ground state is of A'2 symmetry with a S-S-H angle of 93.2°. Ground state geometries, vibrational frequencies, and electron affinities have been computed at all levels of theory. Our CCSD(T)/aug-cc-pVQZ adiabatic electron affinity of 2.34eV for the Si2H radical is in excellent agreement with the photoelectron spectroscopy experiments of Xu et al. [J. Chem. Phys. 108, 7645 (1998)], where the electron affinity was determined to be 2.31±0.01eV.

  18. Band structure and optical response of 2H-Mo X2 compounds ( X=S , Se, and Te)

    Reshak, Ali Hussain; Auluck, Sushil

    2005-04-01

    We report calculations of the electronic and optical properties for the 2H-MoX2 (X=S,Se,Te) compounds using the full potential linear augmented plane wave method within the local density approximation. When S is replaced by Se and Te, the energy gap changes and the bandwidth of the Mo-d bands reduces. From the partial density of states we find a strong hybridization between Mo-d and X-p states below the Fermi energy EF . On going from S to Se to Te the structures in the frequency-dependent imaginary part of the dielectric function ɛ2(ω) shifts towards lower energies. The frequency-dependent reflectivity and absorption show that the plasma minimum also shifts towards lower energies. We compare our calculations with the experimental optical data and find a good agreement.

  19. Reactive scattering of carbon atoms: the reaction dynamics of C(3P, 1D) +C2H2 and C2H4

    The reaction dynamics of C(3P, 1D) with acetylene and ethylene have been investigated by using the crossed beam technique with mass spectrometric detection and time-of-flight (TOF) analysis. The novel capability of generating continuous supersonic beams of carbon atoms by a radio-frequency discharge beam source is exploited. From angular and velocity distribution measurements, the primary reaction products are identified, their relative importance assessed, and their dynamics of formation characterized. While the reaction C(3P) + C2H2(X1Σg+) has been found to lead to C3H + H and C3(X1Σg+) + H2(X1Σg+) in comparable amount, the reaction C(3P) + C2H4(X1At) has been found to lead, predominantly, to H + C3H3 (propargylene). The dynamics of the C(1D) reactions are also characterized. The spin-forbidden H2 elimination channel in the reaction C(3P) + C2H2 is attributed to the occurrence of inter-system-crossing between the triplet and singlet manifold of the C3H2 potential energy surfaces. Interestingly, these findings provide evidence that the C(3P) + C2H2 reaction maybe the source of both C3H and C3 species detected in the extreme environment of dense interstellar clouds and outflows of carbon stars, as well as in combustion systems. (author)

  20. SMA observations of C2H in High-Mass Star Forming Regions

    Jiang, Xue-Jian; Zhang, Qizhou; Wang, Junzhi; Zhang, Zhi-Yu; Li, Juan; Gao, Yu; Gu, Qiusheng

    2015-01-01

    C$_2$H is a representative hydrocarbon that is abundant and ubiquitous in the interstellar medium (ISM). To study its chemical properties, we present Submillimeter Array (SMA) observations of the C$_2$H $N=3-2$ and HC$_3$N $J=30-29$ transitions and the 1.1 mm continuum emission toward four OB cluster-forming regions, AFGL 490, ON 1, W33 Main, and G10.6-0.4, which cover a bolometric luminosity range of $\\sim$10$^3$--10$^6$ $L_{\\odot}$. We found that on large scales, the C$_2$H emission traces the dense molecular envelope. However, for all observed sources, the peaks of C$_2$H emission are offset by several times times 10$^4$ AU from the peaks of 1.1 mm continuum emission, where the most luminous stars are located. By comparing the distribution and profiles of C$_2$H hyperfine lines and the 1.1 mm continuum emission, we find that the C$_2$H column density (and abundance) around the 1.1 mm continuum peaks is lower than those in the ambient gas envelope. Chemical models suggest that C$_2$H might be transformed to...

  1. Chromatin remodeling enzyme Snf2h regulates embryonic lens differentiation and denucleation.

    He, Shuying; Limi, Saima; McGreal, Rebecca S; Xie, Qing; Brennan, Lisa A; Kantorow, Wanda Lee; Kokavec, Juraj; Majumdar, Romit; Hou, Harry; Edelmann, Winfried; Liu, Wei; Ashery-Padan, Ruth; Zavadil, Jiri; Kantorow, Marc; Skoultchi, Arthur I; Stopka, Tomas; Cvekl, Ales

    2016-06-01

    Ocular lens morphogenesis is a model for investigating mechanisms of cellular differentiation, spatial and temporal gene expression control, and chromatin regulation. Brg1 (Smarca4) and Snf2h (Smarca5) are catalytic subunits of distinct ATP-dependent chromatin remodeling complexes implicated in transcriptional regulation. Previous studies have shown that Brg1 regulates both lens fiber cell differentiation and organized degradation of their nuclei (denucleation). Here, we employed a conditional Snf2h(flox) mouse model to probe the cellular and molecular mechanisms of lens formation. Depletion of Snf2h induces premature and expanded differentiation of lens precursor cells forming the lens vesicle, implicating Snf2h as a key regulator of lens vesicle polarity through spatial control of Prox1, Jag1, p27(Kip1) (Cdkn1b) and p57(Kip2) (Cdkn1c) gene expression. The abnormal Snf2h(-/-) fiber cells also retain their nuclei. RNA profiling of Snf2h(-/) (-) and Brg1(-/-) eyes revealed differences in multiple transcripts, including prominent downregulation of those encoding Hsf4 and DNase IIβ, which are implicated in the denucleation process. In summary, our data suggest that Snf2h is essential for the establishment of lens vesicle polarity, partitioning of prospective lens epithelial and fiber cell compartments, lens fiber cell differentiation, and lens fiber cell nuclear degradation. PMID:27246713

  2. Trends and variations in CO, C2H6, and HCN in the Southern Hemisphere point to the declining anthropogenic emissions of CO and C2H6

    N. B. Jones

    2012-08-01

    Full Text Available We analyse the carbon monoxide (CO, ethane (C2H6 and hydrogen cyanide (HCN partial columns (from the ground to 12 km derived from measurements by ground-based solar Fourier Transform Spectroscopy at Lauder, New Zealand (45° S, 170° E, and at Arrival Heights, Antarctica (78° S, 167° E, from 1997 to 2009. Significant negative trends are calculated for all species at both locations, based on the daily-mean observed time series, namely CO (−0.94 ± 0.47% yr−1, C2H6 (−2.37 ± 1.18% yr−1 and HCN (−0.93 ± 0.47% yr−1 at Lauder and CO (−0.92 ± 0.46% yr−1, C2H6 (−2.82 ± 1.37% yr−1 and HCN (−1.41 ± 0.71% yr−1 at Arrival Heights. The uncertainties reflect the 95% confidence limits. However, the magnitudes of the trends are influenced by the anomaly associated with the 1997–1998 El Niño Southern Oscillation event at the beginning of the time series reported. We calculate trends for each month from 1997 to 2009 and find negative trends for all months. The largest monthly trends of CO and C2H6 at Lauder, and to a lesser degree at Arrival Heights, occur during austral spring during the Southern Hemisphere tropical and subtropical biomass burning period. For HCN, the largest monthly trends occur in July and August at Lauder and around November at Arrival Heights. The correlations between CO and C2H6 and between CO and HCN at Lauder in September to November, when the biomass burning maximizes, are significantly larger that those in other seasons. A tropospheric chemistry-climate model is used to simulate CO, C2H6, and HCN partial columns for the period of 1997–2009, using interannually varying biomass burning emissions from GFED3 and annually periodic but seasonally varying emissions from both biogenic and anthropogenic sources. The model-simulated partial columns of these species compare well with the measured partial columns and the model accurately reproduces seasonal cycles of all three species at both locations. However

  3. Optical emission spectroscopy study of premixed C2H4/O2 and C2H4/C2H2/O2 flames for diamond growth with and without CO2 laser excitation

    He, X. N.; Gebre, T.; Shen, X. K.; Xie, Z. Q.; Zhou, Y. S.; Lu, Y. F.

    2010-02-01

    Optical emission spectroscopy (OES) measurements were carried out to study premixed C2H4/O2 and C2H4/C2H2/O2 combustion flame for diamond deposition with and without a CO2 laser excitation. Strong emissions from radicals C2 and CH were observed in the visible range in all the OES spectra acquired. By adding a continuous-wave CO2 laser to irradiate the flame at a wavelength of 10.591 μm, the common CO2 laser wavelength, it was discovered that the emission intensities of the C2 and CH radicals were increased due to the laser beam induced excitation. OES measurements of the C2 and CH radicals were performed using different gas combinations and laser powers. The rotational temperatures in the flame were determined by analyzing the spectra of the R-branch of the A2Δ-->X2Π (0, 0) electronic transition near 430 nm (CH band head). Information obtained from the OES spectra, including the emission intensities of the C2 and CH radicals, the intensity ratios, and the rotational temperatures, was integrated into the study of diamond deposition on tungsten carbide substrates for mechanism analysis of the laser induced vibrational excitation and laser-assisted diamond deposition.

  4. New determination of the {sup 2}H(d,p){sup 3}H and {sup 2}H(d,n){sup 3}He reaction rates at astrophysical energies

    Tumino, A.; Spartà, R.; Spitaleri, C.; Pizzone, R. G.; La Cognata, M.; Rapisarda, G. G.; Romano, S.; Sergi, M. L. [Laboratori Nazionali del Sud-INFN, Catania (Italy); Mukhamedzhanov, A. M. [Cyclotron Institute Texas A and M University-College Station, Texas (United States); Typel, S. [GSI Helmholtzzentrum für Schwerionenforschung GmbH-Theorie Darmstadt (Germany); Tognelli, E.; Degl' Innocenti, S.; Prada Moroni, P. G. [Dipartimento di Fisica, Università di Pisa, and INFN-Sezione di Pisa, Pisa (Italy); Burjan, V.; Kroha, V.; Hons, Z.; Mrazek, J.; Piskor, S. [Nuclear Physics Institute of ASCR-Rez near Prague (Czech Republic); Lamia, L., E-mail: tumino@lns.infn.it [Dipartimento di Fisica e Astronomia, Università degli Studi di Catania, Catania (Italy)

    2014-04-20

    The cross sections of the {sup 2}H(d,p){sup 3}H and {sup 2}H(d,n){sup 3}He reactions have been measured via the Trojan Horse method applied to the quasi-free {sup 2}H({sup 3}He,p {sup 3}H){sup 1}H and {sup 2}H({sup 3}He,n {sup 3}He){sup 1}H processes at 18 MeV off the proton in {sup 3}He. For the first time, the bare nucleus S(E) factors have been determined from 1.5 MeV, across the relevant region for standard Big Bang nucleosynthesis, down to the thermal energies of deuterium burning in the pre-main-sequence (PMS) phase of stellar evolution, as well as of future fusion reactors. Both the energy dependence and the absolute value of the S(E) factors deviate by more than 15% from the available direct data and existing fitting curves, with substantial variations in the electron screening by more than 50%. As a consequence, the reaction rates for astrophysics experience relevant changes, with a maximum increase of up to 20% at the temperatures of the PMS phase. From a recent primordial abundance sensitivity study, it turns out that the {sup 2}H(d,n){sup 3}He reaction is quite influential on {sup 7}Li, and the present change in the reaction rate leads to a decrease in its abundance by up to 10%. The present reaction rates have also been included in an updated version of the FRANEC evolutionary code to analyze their influence on the central deuterium abundance in PMS stars with different masses. The largest variation of about 10%-15% pertains to young stars (≤1 Myr) with masses ≥1 M {sub ☉}.

  5. Stress corrosion cracking of 13Cr steels in CO2-H2S-Cl- environments

    SCC behavior of two type 13Cr steels was investigated in aqueous CO2/H2S environments. The 13Cr steels were less resistant to SCC in CO2/H2S environments than low alloy steels, but some 13Cr steels were not subject to SCC even at a hydrogen sulfide partial pressure of 0.3 atm. Further, it was found that SCC in a CO2/H2S environment was caused by hydrogen embrittlement and that the SCC susceptibility of 13Cr steels was affected by their intergranular cracking behavior. Thus, their microstructures and carbide dispersions are important factors to SCC susceptibility of 13Cr steels

  6. Experimental and kinetic modeling study of C2H4 oxidation at high pressure

    Lopez, Jorge Gimenez; Rasmussen, Christian Lund; Alzueta, Maria;

    2009-01-01

    A detailed chemical kinetic model for oxidation of C2H4 in the intermediate temperature range and high pressure has been developed and validated experimentally. New ab initio calculations and RRKM analysis of the important C2H3 + O-2 reaction was used to obtain rate coefficients over a wide range...... bar, varying the reaction stoichiometry from very lean to fuel-rich conditions. Model predictions are generally satisfactory. The governing reaction mechanisms are outlined based on calculations with the kinetic model. Under the investigated conditions the oxidation pathways for C2H4 are more complex...

  7. Determination of the delta(2H/1H)of Water: RSIL Lab Code 1574

    Revesz, Kinga; Coplen, Tyler B.

    2008-01-01

    Reston Stable Isotope Laboratory (RSIL) lab code 1574 describes a method used to determine the relative hydrogen isotope-ratio delta(2H,1H), abbreviated hereafter as d2H of water. The d2H measurement of water also is a component of the National Water Quality Laboratory (NWQL) schedules 1142 and 1172. The water is collected unfiltered in a 60-mL glass bottle and capped with a Polyseal cap. In the laboratory, the water sample is equilibrated with gaseous hydrogen using a platinum catalyst (Horita, 1988; Horita and others, 1989; Coplen and others, 1991). The reaction for the exchange of one hydrogen atom is shown in equation 1.

  8. One-step fabrication of nickel nanocones by electrodeposition using CaCl2·2H2O as capping reagent

    Lee, Jae Min; Jung, Kyung Kuk; Lee, Sung Ho; Ko, Jong Soo

    2016-04-01

    In this research, a method for the fabrication of nickel nanocones through the addition of CaCl2·2H2O to an electrodeposition solution was proposed. When electrodeposition was performed after CaCl2·2H2O addition, precipitation of the Ni ions onto the (2 0 0) crystal face was suppressed and anisotropic growth of the nickel electrodeposited structures was promoted. Sharper nanocones were produced with increasing concentration of CaCl2·2H2O added to the solution. Moreover, when temperature of the electrodeposition solutions approached 60 °C, the apex angle of the nanostructures decreased. In addition, the nanocones produced were applied to superhydrophobic surface modification using a plasma-polymerized fluorocarbon (PPFC) coating. When the solution temperature was maintained at 60 °C and the concentration of the added CaCl2·2H2O was 1.2 M or higher, the fabricated samples showed superhydrophobic surface properties. The proposed nickel nanocone formation method can be applied to various industrial fields that require metal nanocones, including superhydrophobic surface modification.

  9. Deuterium MR in vivo imaging of the rat eye using 2H2O

    In vivo deuterium MR imaging (2H MR) was investigated in rats after intraperitoneal administration of deuterated saline, and a dynamic study of the water movement in rat eyes was performed. Deuterium MR imaging was carried out by means of a gradient-echo (GRE) and a spin-echo (SE) pulse sequence. The rat eye was imaged in 2H MR more selectively by SE than by GRE, but a lower signal-to-noise ratio was obtained in 2H MR imaging using the SE sequence. The MR signal intensity of the rat eye was followed by a 3-compartment model, which enabled determination of the flow rate constant of the water in the eye (0.359/min). Deuterium MR imaging is useful to visualize the dynamic change of water in rat eyes using 2H MR at the same magnetic field (2 T) that can also be used for conventional MR imaging in humans. (orig.)

  10. Structural, mechanical, and electronic properties of monoclinic N2H5N3 under pressure

    Structural, elastic, mechanical, and electronic properties of monoclinic N2H5N3 at zero and high pressure have been investigated using the plane-wave ultrasoft pseudopotential method within the density-functional theory (DFT). The pressure dependences of structural parameters, elastic constants, mechanical properties, band gaps, and density of states of monoclinic N2H5N3 have been calculated and discussed. The obtained results show that monoclinic N2H5N3 is unstable at pressures exceeding the value 126.1 GPa. The ratio of B/G and the Cauchy’s pressure indicate that monoclinic N2H5N3 behaves in ductile nature with pressure ranging from 0 to 200 GPa. (author)

  11. Calculation of dissociating autoionizing states using the block diagonalization method: Application to N2H

    We report the calculation of preliminary potential surfaces necessary to treat dissociative recombination (DR) of electrons with N2H+. We performed multi-reference, configuration interaction calculations with a large active space for N2H+ and N2H, using the GAMESS electronic structure code. Rydberg-valence coupling is strong in N2H, and a systematic procedure is desirable to isolate the appropriate dissociating, autoionizing states. We used the block diagonalization method, which requires only modest additional effort beyond the standard methodology. We treated both linear and bent geometries of the molecules, with N2 fixed at its equilibrium separation. The results indicate that the crossing between the dissociating neutral curve and the initial ion potential is not favorably located, suggesting that the direct mechanism for DR will be small. Dynamics calculations using the multi-configuration, time-dependent Hartree (MCTDH) method confirm this conclusion.

  12. Rings of C2H in the Molecular Disks Orbiting TW Hya and V4046 Sgr

    Kastner, J H; Gorti, U; Hily-Blant, P; Oberg, K; Forveille, T; Andrews, S; Wilner, D

    2015-01-01

    We have used the Submillimeter Array to image, at ~1" resolution, C2H(3-2) emission from the molecule-rich circumstellar disks orbiting the nearby, classical T Tauri star systems TW Hya and V4046 Sgr. The SMA imaging reveals that the C2H emission exhibits a ring-like morphology within each disk, the inner hole radius of the C2H ring within the V4046 Sgr disk (~70 AU) is somewhat larger than than of its counterpart within the TW Hya disk (~45 AU). We suggest that, in each case, the C2H emission likely traces irradiation of the tenuous surface layers of the outer disks by high-energy photons from the central stars.

  13. Direct Experimental Verification of Neutron Acceleration by the Material Optical Potential of Solid 2H2

    We have measured the acceleration of neutrons by the material optical potential of solid 2H2. Using a gravitational spectrometer, we find a minimal kinetic energy Ec=(99±7) neV of neutrons from a superthermal ultracold neutron (UCN) source with solid 2H2 as an UCN converter. The result is in excellent agreement with theoretical predictions, Ec=106 neV

  14. Adsorption geometry of PTCDA on 2H-NbSe2

    Low-temperature scanning tunnelling microscopy of submonolayers of PTCDA adsorbed on 2H-NbSe2 reveals an adsorbate layer that is neither commensurate with the substrate lattice nor with the charge density wave periodicity. The observed smallness of deviations from the PTCDA bulk-state unit-cell dimensions indicates that PTCDA film formation is dominated by intermolecular interactions rather than by interaction between PTCDA and 2H-NbSe2. (orig.)

  15. Lewis acid Mediated Aza-Diels-Alder Reactions and Asymmetric Alkylations of 2H-azirines

    Risberg, Erik

    2004-01-01

    This thesis describes the use of 2H-azirines, three-membered unsaturatednitrogen-containing heterocycles, as reactive intermediates ina number of Lewis acid promoted alkylations and Diels-Alderreactions providing synthetically useful aziridines. In order to carry out this investigation a new generalprocedure for the ring closure of vinyl azides, forming theresultant 3-substituted-2H-azirines, was developed applying low boiling solventsin closed reaction vessels at elevated temperatures. The a...

  16. A Forward Chemical Screen Using Zebrafish Embryos with Novel 2-Substituted 2H-Chromene Derivatives

    Torregroza, Ingrid; Evans, Todd; Das, Bhaskar C.

    2009-01-01

    We synthesized 2-substituted 2H-chromene derivatives from salicylaldehyde using potassium vinylic borates in the presence of secondary amines. Our goal was to generate novel compounds that might modulate transforming growth factor-β signaling, based on limited rational design. Potassium vinyl trifluoroborates react with salicylaldehydes at 80 °C in the presence of a secondary amine and produce 2-substituted 2H-chromene derivatives with a 70–90% yield. A small library of these compounds, predi...

  17. Investigation on the Interactions of NiCR and NiCR-2H with DNA

    Chitranshi, Priyanka; Chen, Chang-Nan; Jones, Patrick R.; Faridi, Jesika S.; Xue, Liang

    2010-01-01

    We report here a biophysical and biochemical approach to determine the differences in interactions of NiCR and NiCR-2H with DNA. Our goal is to determine whether such interactions are responsible for the recently observed differences in their cytotoxicity toward MCF-7 cancer cells. Viscosity measurement and fluorescence displacement titration indicated that both NiCR and NiCR-2H bind weakly to duplex DNA in the grooves. The coordination of NiCR-2H with the N-7 of 2′-deoxyguanosine 5′-monophosphate (5′-dGMP) is stronger than that of NiCR as determined by 1H NMR. NiCR-2H, like NiCR, can selectively oxidize guanines present in distinctive DNA structures (e.g., bulges), and notably, NiCR-2H oxidizes guanines more efficiently than NiCR. In addition, UV and 1H NMR studies revealed that NiCR is oxidized into NiCR-2H in the presence of KHSO5 at low molar ratios with respect to NiCR (≤4). PMID:20671951

  18. Broad N2H+ emission towards the protostellar shock L1157-B1

    Codella, C; Ceccarelli, C; Lefloch, B; Benedettini, M; Busquet, G; Caselli, P; Fontani, F; Gómez-Ruiz, A; Podio, L; Vasta, M

    2013-01-01

    We present the first detection of N2H+ towards a low-mass protostellar outflow, namely the L1157-B1 shock, at about 0.1 pc from the protostellar cocoon. The detection was obtained with the IRAM 30-m antenna. We observed emission at 93 GHz due to the J = 1-0 hyperfine lines. The analysis of the emission coupled with the HIFI CHESS multiline CO observations leads to the conclusion that the observed N2H+(1-0) line originates from the dense (> 10^5 cm-3) gas associated with the large (20-25 arcsec) cavities opened by the protostellar wind. We find a N2H+ column density of few 10^12 cm-2 corresponding to an abundance of (2-8) 10^-9. The N2H+ abundance can be matched by a model of quiescent gas evolved for more than 10^4 yr, i.e. for more than the shock kinematical age (about 2000 yr). Modelling of C-shocks confirms that the abundance of N2H+ is not increased by the passage of the shock. In summary, N2H+ is a fossil record of the pre-shock gas, formed when the density of the gas was around 10^4 cm-3, and then furth...

  19. Resolved Depletion Zones and Spatial Differentiation of N2H+ and N2D+

    Tobin, John J; Hartmann, Lee; Lee, Jeong-Eun; Maret, Sebastien; Myers, Phillip C; Looney, Leslie W; Chiang, Hsin-Fang; Friesen, Rachel

    2013-01-01

    We present a study on the spatial distribution of N2D+ and N2H+ in thirteen protostellar systems. Eight of thirteen objects observed with the IRAM 30m telescope show relative offsets between the peak N2D+ (J=2-1) and N2H+ (J=1-0) emission. We highlight the case of L1157 using interferometric observations from the Submillimeter Array and Plateau de Bure Interferometer of the N2D+ (J=3-2) and N2H+ (J=1-0) transitions respectively. Depletion of N2D+ in L1157 is clearly observed inside a radius of ~2000 AU (7") and the N2H+ emission is resolved into two peaks at radii of ~1000 AU (3.5"), inside the depletion region of N2D+. Chemical models predict a depletion zone in N2H+ and N2D+ due to destruction of H2D+ at T ~ 20 K and the evaporation of CO off dust grains at the same temperature. However, the abundance offsets of 1000 AU between the two species are not reproduced by chemical models, including a model that follows the infall of the protostellar envelope. The average abundance ratios of N2D+ to N2H+ have been ...

  20. H2-H2O-HI Hydrogen Separation in H2-H2O-HI Gaseous Mixture Using the Silica Membrane

    It was evaluated aiming at the application for hydrogen iodide decomposition in the thermochemical lS process. Porous alumina tube having pore size of 0.1 μm was modified by chemical vapor deposition using tetraethoxysilane. The permeance single gas of He, H2, and N2 was measured at 300-600 oC. Hydrogen permeance of the modified membrane at a permeation temperature of 600 oC was about 5.22 x 10-08 mol/Pa m2 s, and 3.2 x 10-09 of using gas mixture of H2-H2O-HI, where as HI permeances was below 1 x 10-10 mol/Pa m2 s. The Hydrogen permeance relative was not changed after 25 hours exposure in a mixture of H2-H2O-HI gas at the temperature of 450 oC. (author)

  1. {sup 2}H(d,p){sup 3}H and {sup 2}H(d,n){sup 3}He reactions at sub-coulomb energies

    Tumino, A.; Spitaleri, C.; Mukhamedzhanov, A. M.; Typel, S.; Sparta, R.; Aliotta, M.; Kroha, V.; Hons, Z.; La Cognata, M.; Lamia, L.; Pizzone, R. G.; Mrazek, J.; Pizzone, R. G.; Rapisarda, G. G.; Romano, S.; Sergi, M. L. [Universita degli Studi di Enna Kore, and Laboratori Nazionali del Sud - INFN, via S. Sofia 62, 95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Universita di Catania, and Laboratori Nazionali del Sud - INFN, via S. Sofia 62, 95123 Catania (Italy); Cyclotron Institute Texas A and M University - College Station, Texas (United States); Excellence Cluster Universe - Technische Universitaet Muenchen, Garching, Germany and GSI Helmholtzzentrum fuer Schwerionenforschung GmbH - Theorie Darmstadt (Germany); Dipartimento di Fisica e Astronomia, Universita di Catania, and Laboratori Nazionali del Sud - INFN, via S. Sofia 62, 95123 Catania (Italy); School of Physics and Astronomy - University of Edinburgh, SUPA (United Kingdom); Nuclear Physics Institute of ASCR - Rez near Prague (Czech Republic); Dipartimento di Fisica e Astronomia, Universita di Catania, and Laboratori Nazionali del Sud - INFN, via S. Sofia 62, 95123 Catania (Italy); Nuclear Physics Institute of ASCR - Rez near Prague (Czech Republic); Dipartimento di Fisica e Astronomia, Universita di Catania, and Laboratori Nazionali del Sud - INFN, via S. Sofia 62, 95123 Catania (Italy)

    2012-11-20

    The {sup 2}H({sup 3}He,p{sup 3}H){sup 1}H and {sup 2}H({sup 3}He,n{sup 3}He){sup 1}H processes have been measured in quasi free kinematics to investigate for the first time the {sup 2}H(d,p){sup 3}H and {sup 2}H(d,n){sup 3}He reactions by means of the Trojan Horse Method. The {sup 3}He+d experiment was performed at 18 MeV, corresponding the a d-d energy range from 1.5 MeV down to 2 keV. This range overlaps with the relevant region for Standard Big Bang Nucleosynthesis as well as with the thermal energies of future fusion reactors and deuterium burning in the Pre Main Sequence phase of stellar evolution. This is the first pioneering experiment in quasi free regime where the charged spectator is detected. Both the energy dependence and the absolute value of the bare nucleus S(E) factors have been extracted for the first time. They deviate by more than 15% from available direct data with new S(0) values of 57.4{+-}1.8 MeVb for {sup 3}H+p and 60.1{+-}1.9 MeVb for {sup 3}He+n. None of the existing fitting curves is able to provide the correct slope of the new data in the full range, thus calling for a revision of the theoretical description. This has consequences in the calculation of the reaction rates with more than a 25% increase at the temperatures of future fusion reactors.

  2. Drivers of δ2H variations in an idealized extratropical cyclone

    Dütsch, Marina; Pfahl, Stephan; Wernli, Heini

    2016-05-01

    Numerical model simulations of stable water isotopes help to improve our understanding of the complex processes driving isotopic variability in atmospheric moisture. We use the isotope-enabled Consortium for Small-Scale Modelling (COSMO) model to study the governing mechanisms of δ2H variations in an idealized extratropical cyclone. A set of experiments with differing initial conditions of δ2H in vapor and partly deactivated isotopic fractionation allows us to quantify the relative roles of cloud fractionation and vertical and horizontal advection for the simulated δ2H signals associated with the cyclone and fronts. Horizontal transport determines the large-scale pattern of δ2H in both vapor and precipitation, while fractionation and vertical transport are more important on a smaller scale, near the fronts. During the passage of the cold front fractionation leads to a V-shaped trend of δ2H in precipitation and vapor, which is, for vapor, superimposed on a gradual decrease caused by the arrival of colder air masses.

  3. Isolation and purification of BVⅠ-2H from bee venom and analysis of its biological action

    2002-01-01

    The medical use of bee venom for rheumatoid arthritis ( RA ) has a very long tradition. In this study, isolation and purification of polypeptides from bee venom were carried out on sephadex chromatography, heparin sepharose CL-6B chromatography and HPLC. Several fractions were extracted, and their effects on activation of splenocyte and THP-1 cell were studied. The inhibitory fraction was selected for further studies. Finally, BVⅠ-2H that the HPLC elution profiles was a single peak was isolated by C8 column. ESI- MS detection results showed that BVⅠ-2H was a fraction of bee venom, and the molecular weight of the major component was 644.8. BVⅠ-2H could inhibit ConA-induced splenocyte proliferation, IL-1 production and interfere with splenocyte cycle in mice. Moreover, BVⅠ-2H could inhibit PMA-induced TNFα production in THP-1 cells, which was due to its inhibitory effects on TNFα mRNA expression and protein phosphorylation of IκBα. Our studies indicated that BVⅠ-2H was one of the anti-inflammatory components of bee venom.

  4. Ethynyl (C2H) in massive star formation: Tracing the initial conditions?

    Beuther, H; Henning, T; Linz, H

    2008-01-01

    APEX single-dish observations at sub-millimeter wavelengths toward a sample of massive star-forming regions reveal that C2H is almost omni-present toward all covered evolutionary stages from Infrared Dark Clouds via High-Mass Protostellar Objects to Ultracompact HII regions. High-resolution data from the Submillimeter Array toward one hot-core like High-Mass Protostellar Object show a shell-like distribution of C2H with a radius of ~9000AU around the central submm peak position. These observed features are well reproduced by a 1D cloud model with power-law density and temperature distributions and a gas-grain chemical network. The reactive C2H radical (ethynyl) is abundant from the onset of massive star formation, but later it is rapidly transformed to other molecules in the core center. In the outer cloud regions the abundance of C2H remains high due to constant replenishment of elemental carbon from CO being dissociated by the interstellar UV photons. We suggest that C2H may be a molecule well suited to stu...

  5. Natural 4-Hydroxy-2,5-dimethyl-3(2H-furanone (Furaneol®

    Wilfried Schwab

    2013-06-01

    Full Text Available 4-Hydroxy-2,5-dimethyl-3(2H-furanone (HDMF, furaneol® and its methyl ether 2,5-dimethyl-4-methoxy-3(2H-furanone (DMMF are import aroma chemicals and are considered key flavor compounds in many fruit. Due to their attractive sensory properties they are highly appreciated by the food industry. In fruits 2,5-dimethyl-3(2H-furanones are synthesized by a series of enzymatic steps whereas HDMF is also a product of the Maillard reaction. Numerous methods for the synthetic preparation of these compounds have been published and are applied by industry, but for the development of a biotechnological process the knowledge and availability of biosynthetic enzymes are required. During the last years substantial progress has been made in the elucidation of the biological pathway leading to HDMF and DMMF. This review summarizes the latest advances in this field.

  6. Hydrogenation-induced atomic stripes on the 2 H -MoS2 surface

    Han, Sang Wook; Yun, Won Seok; Lee, J. D.; Hwang, Y. H.; Baik, J.; Shin, H. J.; Lee, Wang G.; Park, Young S.; Kim, Kwang S.

    2015-12-01

    We report that the hydrogenation of a single crystal 2 H -MoS2 induces a novel-intermediate phase between 2H and 1T phases on its surface, i.e., the large-area, uniform, robust, and surface array of atomic stripes through the intralayer atomic-plane gliding. The total energy calculations confirm that the hydrogenation-induced atomic stripes are energetically most stable on the MoS2 surface between the semiconducting 2H and metallic 1T phase. Furthermore, the electronic states associated with the hydrogen ions, which is bonded to sulfur anions on both sides of the MoS2 surface layer, appear in the vicinity of the Fermi level (EF) and reduces the band gap. This is promising in developing the monolayer-based field-effect transistor or vanishing the Schottky barrier for practical applications.

  7. A Novel Orange Juice Concentration Method Based on C2H4 Clathrate Hydrate Formation

    Shifeng Li

    2014-06-01

    Full Text Available A novel orange juice concentration method by C2H4 hydrate formation was presented. The experiments were carried out in a high-pressure stirred reactor. The changes of temperature and pressure during C2H4 hydrate formation were discussed under different pressure (2.10 and 4.43 MPa. Dehydration ratio was defined in order to evaluate the separation efficiency. It was found that secondary nucleation happened under higher initial pressure. The dehydration ratios were 20.2 and 99.3% with initial pressure at 2.10 and 4.43 MPa, respectively. The results demonstrated that removal of water by formation of C2H4 hydrate is a potential technology for orange juice concentration.

  8. A SAS2H/KENO-V Methodology for 3D Full Core depletion analysis

    This paper describes the use of a SAS2H/KENO-V methodology for 3D full core depletion analysis and illustrates its capabilities by applying it to burnup analysis of the IRIS core benchmarks. This new SAS2H/KENO-V sequence combines a 3D Monte Carlo full core calculation of node power distribution and a 1D Wigner-Seitz equivalent cell transport method for independent depletion calculation of each of the nodes. This approach reduces by more than an order of magnitude the time required for getting comparable results using the MOCUP code system. The SAS2H/KENO-V results for the asymmetric IRIS core benchmark are in good agreement with the results of the ALPHA/PHOENIX/ANC code system. (author)

  9. New coordination modes in potassium edta salts: K2[H2edta]2H2O, K3[Hedta]2H2O and K4[edta]·3.92H2O.

    Krawczyk, Monika K; Lis, Tadeusz

    2011-07-01

    Three potassium edta (edta is ethylenediaminetetraacetic acid, H(4)Y) salts which have different degrees of ionization of the edta anion, namely dipotassium 2-({2-[bis(carboxylatomethyl)azaniumyl]ethyl}(carboxylatomethyl)azaniumyl)acetate dihydrate, 2K(+)·C(10)H(14)N(2)O(8)(2-)·2H(2)O, (I), tripotassium 2,2'-({2-[bis(carboxylatomethyl)amino]ethyl}ammonio)diacetate dihydrate, 3K(+)·C(10)H(13)N(2)O(8)(3-)·2H(2)O, (II), and tetrapotassium 2,2',2'',2'''-(ethane-1,2-diyldinitrilo)tetraacetate 3.92-hydrate, 4K(+)·C(10)H(12)N(2)O(8)(4-)·3.92H(2)O, (III), were obtained in crystalline form from water solutions after mixing edta with potassium hydroxide in different molar ratios. In (II), a new mode of coordination of the edta anion to the metal is observed. The HY(3-) anion contains one deprotonated N atom coordinated to K(+) and the second N atom is involved in intramolecular bifurcated N-H···O and N-H···N hydrogen bonds. The overall conformation of the HY(3-) anions is very similar to that of the Y(4-) anions in (III), although a slightly different spatial arrangement of the -CH(2)COO(-) groups in relation to (III) is observed, whereas the H(2)Y(2-) anions in (I) adopt a distinctly different geometry. The preferred synclinal conformation of the -NCH(2)CH(2)N- moiety was found for all edta anions. In all three crystals, the anions and water molecules are arranged in three-dimensional networks linked via O-H···O and C-H···O [and N-H···O in (I) and (II)] hydrogen bonds. K···O interactions also contribute to the three-dimensional polymeric architecture of the salts. PMID:21727627

  10. Infrared intensities and optical constants of crystalline C 2H 4 and C 2D 4

    Zhao, G.; Ospina, M. J.; Khanna, R. K.

    Infrared absorption spectra of several thin films of C 2H 4 and C 2D 4 at ˜55 K were investigated at ˜0.6 cm -1 resolution. The integrated band intensities of the infrared active fundamental modes were obtained by a linear fit of the integrated absorbances vs film thickness. An iterative Kramers—Kronig analysis of the absorption data was carried out to obtain the complex refractive indices of crystalline C 2H 4 and C 2D 4 in the regions of absorption bands.

  11. Multicomponent Synthesis of 3,6-Dihydro-2H-1,3-thiazine-2-thiones

    Frans J. J. de Kanter

    2012-02-01

    Full Text Available Non-fused 3,6-dihydro-2H-1,3-thiazine-2-thiones constitute a so far rather unexplored class of compounds, with the latest report dating back more than two decades. Thiazine-2-thiones contain an endocyclic dithiocarbamate group, which is often found in pesticides, in substrates for radical chemistry and in synthetic intermediates towards thioureas and amidines. We now report the multicomponent reaction (MCR of in situ-generated 1-azadienes with carbon disulfide. With this reaction, a one-step protocol towards the potentially interesting 3,6-dihydro-2H-1,3-thiazine-2-thiones was established and a small library was synthesized.

  12. On-board electric vehicle battery charger with enhanced V2H operation mode

    Monteiro, Vítor Duarte Fernandes; Exposto, Bruno Fernandes; Pinto, J. G.; Almeida, Raul Fernando Silva; João C. Ferreira; Meléndez, Andrés A. Nogueiras; João L Afonso

    2014-01-01

    This paper proposes an on-board Electric Vehicle (EV) battery charger with enhanced Vehicle-to-Home (V2H) operation mode. For such purpose was adapted an on-board bidirectional battery charger prototype to allow the Grid-to-Vehicle (G2V), Vehicle-to-Grid (V2G) and V2H operation modes. Along the paper are presented the hardware topology and the control algorithms of this battery charger. The idea underlying to this paper is the operation of the on-board bidirectional ba...

  13. 4-Methyl-2-oxo-2H-chromen-7-yl 4-methoxybenzenesulfonate

    Suman Sinha

    2011-12-01

    Full Text Available In the title compound, C17H14O6S, the 2H-chromene ring is essentially planar, with a maximum deviation of 0.016 (1 Å. The dihedral angle between the 2H-chromene and the benzene rings is 54.61 (5°. The C atom of the methoxy group is close to coplanar with its attached ring [deviation = 0.082 (2 Å]. In the crystal, molecules are connected via C—H...O hydrogen bonds, forming sheets lying parallel to the bc plane. Weak C—H...π interactions are also observed.

  14. Effects of structural modulations on the quasiparticle distribution in 2H-TaSe{sub 2}

    Haenke, Torben; Kordyuk, Alexander; Zabolotnyy, Volodymyr; Evtushinsky, Daniil; Sass, Paul; Hess, Christian; Borisenko, Sergey; Buechner, Bernd [IFW Dresden, Institute for Solid State Research, P.O. Box 270116, D-01171 Dresden (Germany); Berger, Helmut [Institut de Physique Appliquee, EPF, 1015 Lausanne (Switzerland)

    2009-07-01

    We report on a temperature dependent scanning tunneling microscopy (STM) and angle resolved photoemission (ARPES) study of the Cu intercalated dichalcogenide 2H-TaSe{sub 2}. The Cu intercalation leads not only to a lowering of the transition temperature into the commensurate charge-density wave state (CDW) but also to the formation of a {radical}(13) x {radical}(13) superstructure, previously observed for the 1T polytype only. The origin, spectroscopic appearance, and influence of these superstructures on the electronic properties of 2H-TaSe{sub 2} are discussed.

  15. Effects of structural modulations on the quasiparticle distribution in 2H-TaSe2

    We report on a temperature dependent scanning tunneling microscopy (STM) and angle resolved photoemission (ARPES) study of the Cu intercalated dichalcogenide 2H-TaSe2. The Cu intercalation leads not only to a lowering of the transition temperature into the commensurate charge-density wave state (CDW) but also to the formation of a √(13) x √(13) superstructure, previously observed for the 1T polytype only. The origin, spectroscopic appearance, and influence of these superstructures on the electronic properties of 2H-TaSe2 are discussed.

  16. Study of the peak effect phenomenon in single crystals of 2H-NbSe2

    C V Tomy; D Pal; S S Banerjee; S Ramakrishnan; A K Grover; S Bhattacharya; M Higgins; G Balakrishnan; McK Paul

    2002-05-01

    The weakly pinned single crystals of the hexagonal 2H-NbSe2 compound have emerged as prototypes for determining and characterizing the phase boundaries of the possible order–disorder transformations in the vortex matter. We present here a status report based on the ac and dc magnetization measurements of the peak effect phenomenon in three crystals of 2H-NbSe2, in which the critical current densities vary over two orders of magnitude. We sketch the generic vortex phase diagram of a weakly pinned superconductor, which also utilizes theoretical proposals. We also establish the connection between the metastability effects and pinning.

  17. Analytical potential energy surface for O + C2H2 system

    Garashchuk, Sophya; Rassolov, Vitaly A.; Braams, Bastiaan J.

    2013-11-01

    Full-dimensional analytical potential energy surfaces (PESs) for the O(1P) + C2H2 and O(3P) + C2H2 reactions are presented. The PESs are constructed by fitting thousands of ab initio data points using permutationally invariant polynomials [5]. Electronic structure data are obtained within the restricted coupled cluster theory with single and double excitations with perturbative triple corrections and correlation consistent basis set of triple-ζ with diffuse functions. Motivated by experiments, formation of DOCC and cyclic DCCO at collision energies of 2.5-4 eV is examined using quasi-classical trajectory dynamics on the triplet surface.

  18. Trojan Horse particle invariance for 2H(d,p)3H reaction: a detailed study

    Pizzone R.G.; Spitaleri C.; Bertulani C.A.; Mukhamedzhanov A.M.; Blokhintsev L.; La Cognata M.; Lamia L.; Rinollo A.; Spartá R.; Tumino A.

    2014-01-01

    In the last decades the Trojan Horse method has played a crucial role for the measurement of several charged particle induced reactions cross sections of astrophysical interest. To better understand its cornerstones and its applications to physical cases many tests were performed to verify all its properties and the possible future perspectives. The Trojan Horse nucleus invariance for the binary d(d,p)t reaction was therefore tested using the quasi free 2H(6Li, pt)4He and 2H(3He,pt)H reaction...

  19. Protein kinase C-α mediates TNF release process in RBL-2H3 mast cells

    Abdel-Raheem, Ihab T; Hide, Izumi; Yanase, Yuhki; Shigemoto-Mogami, Yukari; SAKAI, Norio; Shirai, Yasuhito; Saito, Naoaki; Hamada, Farid M; El-Mahdy, Nagh A; Elsisy, Alaa El-Din E; Sokar, Samya S; Nakata, Yoshihiro

    2005-01-01

    To clarify the mechanism of mast cell TNF secretion, especially its release process after being produced, we utilized an antiallergic drug, azelastine (4-(p-chlorobenzyl)-2-(hexahydro-1-methyl-1H-azepin-4-yl)-1-(2H)- phthalazinone), which has been reported to inhibit TNF release without affecting its production in ionomycin-stimulated RBL-2H3 cells.Such inhibition was associated with the suppression of an ionomycin-induced increase in membrane-associated PKC activity rather than the suppressi...

  20. A Gas-Phase Investigation of Oxygen-Hydrogen Exchange Reaction of O(3P) + C2H5 → H(2S) + C2H4O

    The gas-phase radical-radical reaction O(3P) + C2H5 (ethyl) → H(2S) + CH3CHO (acetaldehyde) was investigated by applying a combination of vacuum-ultraviolet laser-induced fluorescence spectroscopy in a crossed beam configuration and ab initio calculations. The two radical reactants O(3P) and C2H5 were respectively produced by photolysis of NO2 and supersonic flash pyrolysis of the synthesized precursor azoethane. Doppler profile analysis of the nascent H-atom products in the Lyman-α region revealed that the average translational energy of the products and the average fraction of the total available energy released as translational energy were 5.01 ± 0.72 kcal mol-1 and 6.1%, respectively. The empirical data combined with CBS-QB3 level ab initio theory and statistical calculations demonstrated that the title exchange reaction is a major channel and proceeds via an addition-elimination mechanism through the formation of a short-lived, dynamical addition complex on the doublet potential energy surface. On the basis of systematic comparison with several exchange reactions of hydrocarbon radicals, the observed small kinetic energy release can be explained in terms of the loose transition state with a product-like geometry and a small reverse activation barrier along the reaction coordinate

  1. Synthesis and Crystal Structure of Ni3(admt)6(NCS)6·C2H5OH·2H2O

    2000-01-01

    Reaction of nickel (Ⅱ) perchlorate with 4-amino-3,5-dimethyl-1,2,4-triaxole(admt)and NG4NCS gave a trinuclear complex Ni3(admtrz)6 (NCS)6·C2H5OH·2H2O,C32H58N30Ni3O3S6.The compound crystallizes in the orthorhombic space group Pbca(#61) with a=13. 551(3) , b=25.146(6), c=16.553(4) A, V=5640(2)A 3, Z=4, Mr=1279.47, Dc=1. 507 g/cm3; μ(Mo-Kα)=12.70 cm-1 and F(000) = 2656. The final refinement with 2543 observed reflections is converged with R= 0. 058 and Rw= 0. 069. In the Ni3 (admt)6 (NCS)6 molecule, the central nickel atom is coordinated in a distorted octahedral environment by four triazole bridges and two thiocyanate bridges. The terminal nickel atoms are in addition coordinated by two thiocyanate and one admtrz ligand, and thus also have a distorted octahedral geometry.Ni-N distances are 2.040(7)-2. 222(7) A, Ni-Ni distances are 3. 411(1) A.

  2. Investigation of Compton profiles of NO and C2H2%NO与C2H2的康普顿轮廓研究

    马永朋; 赵小利; 刘亚伟; 徐龙泉; 康旭; 倪冬冬; 闫帅; 朱林繁; 杨科

    2015-01-01

    The Compton profiles of nitric oxide and acetylene molecules have been determined at an incident photon energy of 20 keV. Compton profile measurements are carried out with the beamline BL15U1 at the Shanghai Synchrotron Radiation Facility (SSRF). A dedicated gas cell is used, in which diffuse scattering is effectively suppressed. By considering that the statistical accuracy of 0.2%at pz ≈0 is achieved, the Compton profiles of NO and C2H2 determined in this paper can serve as the experimental benchmark data. Furthermore, the density functional theory (DFT) and HF calculation for different basis sets are used to calculate the Compton profiles of nitric oxide and acetylene. It is found that the DFT calculations with the diffuse basis sets are closer to the experimental results, indicating that the electronic density distribution of nitric oxide is more diffuse. For acetylene, the HF calculation is of better agreement with the experimental result. To better understand Compton profiles, we have compared them with distributions of electron density by theoretical calculation. There are clear correspondences between them: diffuse distribution is related to the localized profile and complex structure in electron density distribution, which also shows a subtle structure in profile. The present Compton profiles of nitric oxide and acetylene molecules achieved by synchrotron radiation are the most accurate up to now, as far as we know.%基于第三代同步辐射光源,在20 keV的入射X射线能量下测量了NO与C2H2分子的康普顿轮廓.考虑到本次实验结果在pz ≈0附近的统计精度达到了0.2%,本文报道的NO和C2H2的康普顿轮廓可以作为严格检验理论的实验基准.除此之外,还分别采用HF方法及密度泛函方法选用不同的基组计算了NO与C2 H2康普顿轮廓.通过对比实验结果与理论计算,发现对于NO分子,加入弥散函数基组理论计算结果与实验符合更好,说明NO分子基态的电

  3. 脉冲调制射频容性耦合SiH/C2H4/Ar放电的发射光谱诊断%Optical emission spectrometry diagnosis of pulse-modulated RF capacitive coupling discharge in SiH4/C2H4/Ar

    张娇; 张鹏云

    2011-01-01

    Characteristics of pulse-modulated capacitive coupling plasmas in SiH4/C2H4/Ar gas mixture were diagnosed by optical emission spectroscopy.The electron excitation temperature of plasmas was calculated with the five Ar emission spectral lines by Boltzmann slope method.Then, the dependence of the excitation temperature and relative emission intensity on the discharge power, duty cycle, modulation frequency and gas pressure were presented.%本文采用发射光谱法诊断了低气压下氩气(Ar)、硅烷(SiH4)及乙烯(C2H4)混合气体(SiH4/C2H4/Ar)脉冲调制射频放电等离子体特性,利用了Ar发射光谱中的五条谱线通过Boltzmann斜率法计算了电子激发温度,研究了占空比、调制频率、功率及气压等对电子激发温度和谱线相对强度的影响.

  4. N2H+ depletion in the massive protostellar cluster AFGL 5142

    Busquet, Gemma; Zhang, Qizhou; Viti, Serena; Palau, Aina; Ho, Paul T P; Sanchez-Monge, Alvaro

    2010-01-01

    We aim at investigating with high angular resolution the NH3/N2H+ ratio toward the high-mass star-forming region AFGL 5142 in order to study whether this ratio behaves similarly to the low-mass case, for which the ratio decreases from starless cores to cores associated with YSOs. CARMA was used to observe the 3.2 mm continuum and N2H+(1-0) emission. We used NH3(1,1) and (2,2), HCO+(1-0) and H13CO+(1-0) data from the literature and we performed a time-dependent chemical modeling of the region. The 3.2 mm continuum emission reveals a dust condensation of ~23 Msun associated with the massive YSOs, deeply embedded in the strongest NH3 core (hereafter central core). The N2H+ emission reveals two main cores, the western and eastern core, located to the west and to the east of the mm condensation, and surrounded by a more extended and complex structure of ~0.5 pc. Toward the central core the N2H+ emission drops significantly, indicating a clear chemical differentiation in the region. We found low values of the NH3/N...

  5. Photo-induced reactions in the ion-molecule complex Mg+-OCNC2H5

    Sun, Ju-Long; Liu, Haichuan; Han, Ke-Li; Yang, Shihe

    2003-06-01

    Ion-molecule complexes of magnesium cation with ethyl isocyanate were produced in a laser-ablation supersonic expansion nozzle source. Photo-induced reactions in the 1:1 complexes have been studied in the spectral range of 230-410 nm. Photodissociation mass spectrometry revealed the persistent product Mg+ from nonreactive quenching throughout the entire wavelength range. As for the reactive channels, the photoproducts, Mg+OCN and C2H5+, were produced only in the blue absorption band of the complex with low yields. The action spectrum of Mg+(OCNC2H5) consists of two pronounced peaks on the red and blue sides of the Mg+ 32P←32S atomic transition. The ground state geometry of Mg+-OCNC2H5 was fully optimized at B3LYP/6-31+G** level by using GAUSSIAN 98 package. The calculated absorption spectrum of the complex using the optimized structure of its ground state agrees well with the observed action spectrum. Photofragment branching fractions of the products are almost independent of the photolysis photon energy for the 3Px,y,z excitations. The very low branching ratio of reactive products to nonreactive fragment suggests that evaporation is the main relaxation pathway in the photo-induced reactions of Mg+(OCNC2H5).

  6. NEUT development for T2K and relevance of updated 2p2h models

    Wilkinson, Callum

    2015-01-01

    The MiniBooNE large axial-mass anomaly has motivated the development of new theoretical Charged Current Quasi-Elastic (CCQE) cross-section models in recent years. These proceedings review the development of the neutrino simulation generator NEUT to incorporate these more sophisticated CCQE models, including multi-nucleon interaction (2p2h) effects. The fit results on the MINER$\

  7. Synthesis and properties of [(DMSO)2H] trans-[Ru(DMSO)2Cl4

    [(DMSO)2H]trans-[Ru(DMSO)2Cl4] is synthesized through interaction of ruthenium hydroxotrichloride with DMSO in weakly acid acetone or alcoholic solution. The compound is identified by methods of chemical analysis RPA, ESP, EPR and IRS. The complex behaviour in DMSO and acid solutions is studied

  8. Analytical Formulas of Molecular Ion Abundances and N2H+ Ring in Protoplanetary Disks

    Aikawa, Yuri; Nomura, Hideko; Qi, Chunhua

    2015-01-01

    We investigate the chemistry of ion molecules in protoplanetary disks, motivated by the detection of N$_2$H$^+$ ring around TW Hya. While the ring inner radius coincides with the CO snow line, it is not apparent why N$_2$H$^+$ is abundant outside the CO snow line in spite of the similar sublimation temperatures of CO and N$_2$. Using the full gas-grain network model, we reproduced the N$_2$H$^+$ ring in a disk model with millimeter grains. The chemical conversion of CO and N$_2$ to less volatile species (sink effect hereinafter) is found to affect the N$_2$H$^+$ distribution. Since the efficiency of the sink depends on various parameters such as activation barriers of grain surface reactions, which are not well constrained, we also constructed the no-sink model; the total (gas and ice) CO and N$_2$ abundances are set constant, and their gaseous abundances are given by the balance between adsorption and desorption. Abundances of molecular ions in the no-sink model are calculated by analytical formulas, which a...

  9. 4-[(2H-Tetrazol-2-yl)methyl]benzonitrile

    Zhi-Rong Qu; Zheng Xing

    2008-01-01

    The title compound, C9H7N5, was synthesized by reaction of 4-(bromomethyl)benzonitrile and 2H-tetrazole in the presence of KOH. The relative orientation of the planar tetrazole ring and the methylbenzonitrile moiety is (−)-anticlinal. The crystal packing is dominated by van der Waals interactions.

  10. Optimizing GC Injections when Analyzing δ2H of Vanillin for Traceability Studies

    Hansen, Anne-Mette Sølvbjerg; Fromberg, Arvid; Frandsen, Henrik Lauritz

    Column overloading is a problem when analyzing δ2H, due to the low natural abundance of deuterium and poor ionization efficiency of H2. This problem can be overcome by using split injections instead of splitless. In this study we have compared the influence upon the measured isotopic ratios when ...

  11. Structural transition study of NiCl2.2H2O by specific heat

    The specific heat of polycrystalline NiCl2.2H2O measured in an adiabatic calorimeter by the heat-pulse method between 80 and 281 K indicates a first-order phase transition at Tc = (220.0 ± 0.5) K. This confirms a crystallographic transformation first detected by X-ray and EPR methods. (author)

  12. A combined crossed molecular beams and theoretical study of the reaction CN + C2H4

    Highlights: • The CN + C2H4 reaction was investigated in crossed beam experiments. • Electronic structure calculations of the potential energy surface were performed. • RRKM estimates qualitatively reproduce the experimental C2H3NC yield. - Abstract: The CN + C2H4 reaction has been investigated experimentally, in crossed molecular beam (CMB) experiments at the collision energy of 33.4 kJ/mol, and theoretically, by electronic structure calculations of the relevant potential energy surface and Rice–Ramsperger–Kassel–Marcus (RRKM) estimates of the product branching ratio. Differently from previous CMB experiments at lower collision energies, but similarly to a high energy study, we have some indication that a second reaction channel is open at this collision energy, the characteristics of which are consistent with the channel leading to CH2CHNC + H. The RRKM estimates using M06L electronic structure calculations qualitatively support the experimental observation of C2H3NC formation at this and at the higher collision energy of 42.7 kJ/mol of previous experiments

  13. Synthesizing mixed H2/H-infinity dynamic controller using evolutionary algorithms

    Pedersen, Gerulf; Langballe, A.S.; Wisniewski, Rafal

    2001-01-01

    This paper covers the design of an Evolutionary Algorithm (EA), which should be able to synthesize a mixed H2/H-infinity. It will be shown how a system can be expressed as Matrix Inequalities (MI) and these will then be used in the design of the EA. The main objective is to examine whether a mixed...

  14. Synthesizing multi-objective H2/H-infinity dynamic controller using evolutionary algorithms

    Pedersen, Gerulf; Langballe, A.S.; Wisniewski, Rafal

    This paper covers the design of an Evolutionary Algorithm (EA), which should be able to synthesize a mixed H2/H-infinity. It will be shown how a system can be expressed as Matrix Inequalities (MI) and these will then be used in the design of the EA. The main objective is to examine whether a mixed...

  15. Quaternion-valued admissible wavelets and orthogonal decomposition of L2(IG(2),(H))

    ZHAO Jiman; PENG Lizhong

    2007-01-01

    A series of admissible wavelets is fixed, which forms an ortho- normal basis for the Hilbert space of all the quaternion-valued admissible wavelets. It turns out that their corresponding admissible wavelet transforms give an orthogonal decomposition of L2 (IG(2), (H)).

  16. A Search for ^2H, ^3H, and ^3He in Large Solar Flares

    Mewaldt, R. A.; Stone, E. C.

    1983-01-01

    The results of a new study of solar flare H and He isotopes imply that earlier observations have significantly overestimated the abundances of ^2H, ^3H, and ^3He in large solar flares. We find no evidence that solar flare nuclei have suffered any significant amount of fragmentation before escaping from the Sun.

  17. Study of UO2F2 - H2O - HF compounds

    We study various compounds resulting from the interaction of UO2F2 with H2O and HF (gas), and various triple compounds UO2F2 - H2O - HF; the conditions of decomposition and the thermodynamic limits of stability are specified. (author)

  18. LITERATURE REVIEW ON IMPACT OF GLYCOLATE ON THE 2H EVAPORATOR AND THE EFFLUENT TREATMENT FACILITY

    Adu-Wusu, K.

    2012-05-10

    Glycolic acid (GA) is being studied as an alternate reductant in the Defense Waste Processing Facility (DWPF) feed preparation process. It will either be a total or partial replacement for the formic acid that is currently used. A literature review has been conducted on the impact of glycolate on two post-DWPF downstream systems - the 2H Evaporator system and the Effluent Treatment Facility (ETF). The DWPF recycle stream serves as a portion of the feed to the 2H Evaporator. Glycolate enters the evaporator system from the glycolate in the recycle stream. The overhead (i.e., condensed phase) from the 2H Evaporator serves as a portion of the feed to the ETF. The literature search revealed that virtually no impact is anticipated for the 2H Evaporator. Glycolate may help reduce scale formation in the evaporator due to its high complexing ability. The drawback of the solubilizing ability is the potential impact on the criticality analysis of the 2H Evaporator system. It is recommended that at least a theoretical evaluation to confirm the finding that no self-propagating violent reactions with nitrate/nitrites will occur should be performed. Similarly, identification of sources of ignition relevant to glycolate and/or update of the composite flammability analysis to reflect the effects from the glycolate additions for the 2H Evaporator system are in order. An evaluation of the 2H Evaporator criticality analysis is also needed. A determination of the amount or fraction of the glycolate in the evaporator overhead is critical to more accurately assess its impact on the ETF. Hence, use of predictive models like OLI Environmental Simulation Package Software (OLI/ESP) and/or testing are recommended for the determination of the glycolate concentration in the overhead. The impact on the ETF depends on the concentration of glycolate in the ETF feed. The impact is classified as minor for feed glycolate concentrations {le} 33 mg/L or 0.44 mM. The ETF unit operations that will have

  19. Resolving the sources of plasma glucose excursions following a glucose tolerance test in the rat with deuterated water and [U-13C]glucose

    Delgado, T.C.; Barosa, C.; Nunes, P.M.; Cerdán, S.; Geraldes, C.F.G.C.; Jones, J.G.

    2012-01-01

    Sources of plasma glucose excursions (PGE) following a glucose tolerance test enriched with [U-(13)C]glucose and deuterated water were directly resolved by (13)C and (2)H Nuclear Magnetic Resonance spectroscopy analysis of plasma glucose and water enrichments in rat. Plasma water (2)H-enrichment att

  20. Change of plasma visfatin level in the population with different glucose tolerances

    杨媚

    2006-01-01

    Objective To investigate the change of plasma visfatin level and the relationship of plasma visfatin level to body mass index (BMI) , waist hip ratio (WHR) , blood glucose, plasma insulin levels as well as other factors in the subjects with different glucose tolerances. Methods Fasting and glucose loading 2 h plasma visfatin levels were assayed by ELISA in patients with type 2 diabetes

  1. Microbial H2 cycling does not affect δ2H values of ground water

    Landmeyer, J.E.; Chapelle, F.H.; Bradley, P.M.

    2000-01-01

    Stable hydrogen-isotope values of ground water (δ2H) and dissolved hydrogen concentrations (H(2(aq)) were quantified in a petroleum-hydrocarbon contaminated aquifer to determine whether the production/consumption of H2 by subsurface microorganisms affects ground water &delta2H values. The range of &delta2H observed in monitoring wells sampled (-27.8 ‰c to -15.5 ‰c) was best explained, however, by seasonal differences in recharge temperature as indicated using ground water δ18O values, rather than isotopic exchange reactions involving the microbial cycling of H2 during anaerobic petroleum-hydrocarbon biodegradation. The absence of a measurable hydrogen-isotope exchange between microbially cycled H2 and ground water reflects the fact that the amount of H2 available from the anaerobic decomposition of petroleum hydrocarbons is small relative to the amount of hydrogen present in water, even though milligram per liter concentrations of readily biodegradable contaminants are present at the study site. Additionally, isotopic fractionation calculations indicate that in order for H2 cycling processes to affect δ2H values of ground water, relatively high concentrations of H2 (>0.080 M) would have to be maintained, considerably higher than the 0.2 to 26 nM present at this site and characteristic of anaerobic conditions in general. These observations suggest that the conventional approach of using δ2H and δ18O values to determine recharge history is appropriate even for those ground water systems characterized by anaerobic conditions and extensive microbial H2 cycling.

  2. Tailoring the hydrogen desorption thermodynamics of V{sub 2}H by alloying additives

    Kumar, Sanjay, E-mail: sanjay.barc@gmail.com [Fusion Reactor Materials Section, BARC, Mumbai (India); Tiwari, G.P. [R.A. Institute of Technology, Vidya Nagri, Nerul 400709, Navi Mumbai (India); Krishnamurthy, N. [Fusion Reactor Materials Section, BARC, Mumbai (India)

    2015-10-05

    Highlights: • Decomposition of VH{sub 2} is three step process. • Electronic structure and H solubility are correlated. • Addition of hydride forming metal enhance the thermal stability of V{sub 2}H. • Lattices strain energy could decrease thermal stability of V{sub 2}H. - Abstract: Vanadium could be a potential candidate for on board hydrogen storage application because of its high gravimetric hydrogen storage capacity (∼3.8 mass%) which is even better then the most widely explored AB{sub 5}, AB{sub 2} & AB intermetallic compounds. Hydrogen absorption of vanadium takes place at ambient temperature and pressure with fast kinetics. The vanadium hydride (VH{sub 2}) releases hydrogen in two steps: (1) VH{sub 2}(γ){sub (s)} ↔ ½ V{sub 2}H(β){sub (s)} and (2) V{sub 2}H(β){sub (s)} ↔ 2V{sub (s)} + ½ H{sub 2(g)}. First step is achievable at the ambient temperature and pressure conditions while, the second step requires high temperature (590 K). Thus only half of the total hydrogen storage capacity is available for use on subsequent absorption–desorption cycles at the ambient temperature. The usable hydrogen storage capacity of VH{sub 2} at ambient conditions could be enhanced by tailoring the thermodynamics and kinetics of second step of hydrogen desorption reaction. This could be possible by selecting suitable alloy additives. The present study deals with the selection criteria of alloy additives based on the electronic consideration to tailor the hydrogen desorption thermodynamics and kinetics of V{sub 2}H.

  3. Plasma theory

    A series of lectures on plasma theory with the main headings: introduction; charged particles moving in em fields; the liquid model; transport phenomena in the plasma; wave propagation in plasmas; plasma instabilities. 57 figs. (qui)

  4. Equilibrium coefficient of cocrystallization in the system ZnC2O4x2H2O-Mn(2)-H2O

    To determine the equilibrium volume coefficient of cocrystallization (D) of the Mn(2+) impurity, labelled by 54Mn radionuclide with sediment ZpC2O4x2H2O (Mn concentration in aqueous solution is 4x10-6 - 1.86x10-3 mol/l) three methods are used: 1) spontaneous sediment ripening; 2) sediment ripening alternating with wearing of a solid phase; 3) technique of express D determination for difficultly soluble substances in open systems. It is shown that the 1 and 2 methods lead to the same stationary state of the system for which D--0.100+-0.006, and D magnitude is not dependent on initial Mn concentration. The 3 method gives overstated magnitudes of D=O.16+-0.04

  5. THE 2H(alpha, gamma6LI REACTION AT LUNA AND BIG BANG NUCLEOSYNTHETIS

    Carlo Gustavino

    2013-12-01

    Full Text Available The 2H(α, γ6Li reaction is the leading process for the production of 6Li in standard Big Bang Nucleosynthesis. Recent observations of lithium abundance in metal-poor halo stars suggest that there might be a 6Li plateau, similar to the well-known Spite plateau of 7Li. This calls for a re-investigation of the standard production channel for 6Li. As the 2H(α, γ6Li cross section drops steeply at low energy, it has never before been studied directly at Big Bang energies. For the first time the reaction has been studied directly at Big Bang energies at the LUNA accelerator. The preliminary data and their implications for Big Bang nucleosynthesis and the purported 6Li problem will be shown.

  6. Crystal structure of (6-bromo-2-oxo-2H-chromen-4-ylmethyl morpholine-4-carbodithioate

    K. Mahesh Kumar

    2015-07-01

    Full Text Available In the title compound, C15H14BrNO3S2, the 2H-chromene ring system is nearly planar, with a maximum deviation of 0.034 (2 Å, and the morpholine ring adopts a chair conformation. The dihedral angle between best plane through the 2H-chromene ring system and the morpholine ring is 86.32 (9°. Intramolecular C—H...S hydrogen bonds are observed. In the crystal, inversion-related C—H...S and C—H...O interactions generate R22(10 and R22(8 rings patterns, respectively. In addition, the crystal packing features π–π interactions between fused benzene rings [centroid–centroid distance = 3.7558 (12 Å].

  7. Preparation of [2`,3`,5`,6`-{sup 2}H{sub 4}]pteroylglutamic acid

    Dueker, S.R.; Clifford, A.J. [Univ. of California, Davis (United States). Dept. of Nutrition; Jones, A.D. [Univ. of California, Davis (United States). Dept. of Food Science and Technology; Smith, G.M. [Univ. of California, Davis (United States). Facility for Advanced Instrumentation

    1995-10-01

    Folic acid plays a key role in nucleic acid biosynthesis, essential for normal cell proliferation and function. Localized folate deficiencies may be related to changes in cytology associated with cancer development; analogs of folic acid, such as methotrexate, are potent chemotherapeutic agents and are widely used either alone or in combination therapy for many types of cancer. In this report we describe the synthesis of a tetra-deuterated folic acid from perdeuterated toluene. The primary intermediate, N-(4-amino [2,3,5,6{sup 2}H{sub 4}]benzolyl)-L-glutamic acid diethyl ester was coupled to N(2`)-acetyl-6-formylpterin to create [2`,3`,5`,6`-{sup 2}H{sub 4}]folic acid. A similar scheme can be used for the preparation of [1`,2`,3`,4`,5`,6`-{sup 13}C{sub 6}] folic acid [{sup 13}C{sub 6}] ring labeled toluene. (author).

  8. The Dissociation Energies of CH4 and C2H2 Revisited

    Partridge, Harry; Bauschlicher, Charles W., Jr.; Langhoff, Stephen R. (Technical Monitor)

    1995-01-01

    The bond dissociation energies of CH4 and C2H2 and their fragments are investigated using basis set extrapolations and high levels of correlation. The computed bond dissociation energies (D(sub e)) are accurate to within 0.2 kcal/mol. The agreement with the experimental (D(sub 0)) values is excellent if we assume that the zero-point energy of C2H is 9.18 kcal/mol. The effect of core (1s) correlation on the bond dissociation energies of C-H bonds is shown to vary from 0.2 to 0.7 kcal/mol and that for C-C bonds varies from 0.4 to 2.2 kcal/mol.

  9. Synthesis and Stereochemical Assignment of Crypto-Optically Active (2) H6 -Neopentane.

    Masarwa, Ahmad; Gerbig, Dennis; Oskar, Liron; Loewenstein, Aharon; Reisenauer, Hans Peter; Lesot, Philippe; Schreiner, Peter R; Marek, Ilan

    2015-10-26

    The determination of the absolute configuration of chiral molecules is at the heart of asymmetric synthesis. Here we probe the spectroscopic limits for chiral discrimination with NMR spectroscopy in chiral aligned media and with vibrational circular dichroism spectroscopy of the sixfold-deuterated chiral neopentane. The study of this compound presents formidable challenges since its stereogenicity is only due to small mass differences. For this purpose, we selectively prepared both enantiomers of (2) H6 -1 through a concise synthesis utilizing multifunctional intermediates. While NMR spectroscopy in chiral aligned media could be used to characterize the precursors to (2) H6 -1, the final assignment could only be accomplished with VCD spectroscopy, despite the fleetingly small dichroic properties of 1. Both enantiomers were assigned by matching the VCD spectra with those computed with density functional theory. PMID:26480341

  10. The 2H Electric Dipole Moment in a Separable Potential Approach

    Afnan I.R.

    2010-04-01

    Full Text Available Measurement of the electric dipole moment (EDM of 2H or of 3He may well come prior to the coveted measurement of the neutron EDM. Exact model calculations for the deuteron are feasible, and we explore here the model dependence of such deuteron EDM calculations. We investigate in a separable potential approach the relationship of the full model calculation to the plane wave approximation, correct an error in an early potential model result, and examine the tensor force aspects of the model results as well as the effect of the short range repulsion found in the realistic, contemporary potential model calculations of Liu and Timmermans. We conclude that, because one-pion exchange dominates the EDM calculation, separable potential model calculations should provide an adequate picture of the 2H EDM until better than 10% measurements are achieved.

  11. Band structure analysis of (1 × 2)-H/Pd(110)-pr

    Shuttleworth, I. G.

    2013-09-01

    A novel method of band structure analysis based on the atomic orbital (AO) coefficients in LCAO-DFT has been applied to the (1 × 2)-H/Pd(110)-pr system. The analysis has revealed symmetry-dependent Pd 4d band splitting due to H ligand effects; ensemble effects due to the (1 × 2) Pd reconstruction are shown to be relatively minor.

  12. Characterization Results for the March 2016 H-Tank Farm 2H Evaporator Overhead Samples

    Nicholson, J. C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-05-09

    This report contains the radioanalytical results of the 2H evaporator overhead sample received at SRNL on March 16, 2016. Specifically, concentrations of 137Cs, 90Sr, and 129I are reported and compared to the corresponding Waste Acceptance Criteria (WAC) limits of the Effluent Treatment Project (ETP) Waste Water Collection Tank (WWCT) (rev. 6). All of the radionuclide concentrations in the sample were found to be in compliance with the ETP WAC limits.

  13. Bis[2-(2H-benzotriazol-2-yl-4-methylphenolato]palladium(II

    Chen-Yen Tsai

    2009-06-01

    Full Text Available In the title complex, [Pd(C13H10N3O2], the PdII atom is tetracoordinated by two N atoms and two O atoms from two bidentate 2-(2H-benzotriazol-2-yl-4-methylphenolate ligands, forming a square-planar environment. The asymmetric unit contains one half molecule in which the Pd atom lies on a centre of symmetry.

  14. Temporal and spatial distributions of δ18O and δ2H in precipitation in Romania

    Nagavciuc, Viorica; Bădăluță, Carmen-Andreea; Perșoiu, Aurel

    2015-04-01

    Stable isotope ratios of meteoric water have an important role in climatic, paleoclimatic, hydrological and meteorological studies. While such data are available from most of Europe, so far, in Romania (East Central Europe), no systematic study of the stable isotopic composition of precipitation exists. In this context, the aim of this study is to analyze the isotopic composition of rainwater, its temporal and spatial distribution, the identification of the main factors influencing these variations and the creation of the first map of spatial distribution of stable isotopes in precipitation in Romania. Between March 2012 and March 2014 we have collected monthly samples from 22 stations in Romania, which were subsequently analyzed for their δ18O and δ2H at the Stable Isotopes Laboratory, Stefan cel Mare University, Suceava, Romania. Precipitation in W and NW Romania plot along the GMWL, while those in the East are slightly below it, on an evaporative trend. The LMWL for Romania is defined as δ2H=7,27*δ18O + 6,92. The W-E gradient in the distribution of δ18O and δ2H are less marked than the N-S ones, with local influences dominating in areas of strong evaporation (intramountain basins, rain-shadow areas etc). In SW, and especially in autumn and winter, Meditteranean cyclones carry moisture from the Eastern Mediterranean, the δ18O and δ2H values in precipitation in the area plotting between the GMWL and the Eastern Mediterranean Meteoric Water Line. The isotopic composition of rainwater in Romania correlates well with air temperature, and is influenced to a lesser extent by other factors such as the amount of precipitation, topography configuration, the effect of continentalism and season of the year.

  15. Generalised permutation branes on a product of cosets Gk1/HxGk2/H

    We study the modifications of the generalized permutation branes defined in hep-th/0509153, which are required to give rise to the non-factorizable branes on a product of cosets Gk1/HxGk2/H. We find that for k1k2 there exists big variety of branes, which reduce to the usual permutation branes, when k1=k2 and the permutation symmetry is restored

  16. Study of the tau- -> 3h- 2h+ nu-tau Decay

    Aubert, B; Boutigny, D; Couderc, F; Gaillard, J M; Hicheur, A; Karyotakis, Yu; Lees, J P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, Michael T; Shelkov, V G; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Steinke, M; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Wilson, F F; Çuhadar-Dönszelmann, T; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Thiessen, D; Khan, A; Kyberd, P; Teodorescu, L; Blinov, A E; Blinov, V E; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M A; Mommsen, R K; Röthel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Foulkes, S D; Gary, J W; Shen, B C; Wang, K; Del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S M; Mancinelli, G; Meadows, B T; Sokoloff, M D; Abe, T; Blanc, F; Bloom, P; Chen, S; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Smith, J G; Zhang, J; Zhang, L; Chen, A; Harton, J L; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q; Altenburg, D; Brandt, T; Brose, J; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Petzold, A; Schubert, J; Schubert, Klaus R; Schwierz, R; Spaan, B; Sundermann, J E; Bernard, D; Bonneaud, G R; Brochard, F; Grenier, P; Schrenk, S; Thiebaux, C; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Lavin, D; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Nikolich, M B; Taylor, G P; Charles, M J; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Yi, J; Biasini, M; Covarelli, R; Pioppi, M; Davier, M; Giroux, X; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F R; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Coleman, J P; Forster, I J; Fry, J R; Gabathuler, Erwin; Gamet, R; Hutchcroft, D E; Parry, R J; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Harrison, P F; Mohanty, G B; Cowan, G; Flack, R L; Flächer, H U; Green, M G; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hart, P A; Hodgkinson, M C; Lafferty, G D; Lyon, A J; Williams, J C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Stängle, H; Willocq, S; Cowan, R; Sciolla, G; Sekula, S J; Taylor, F; Yamamoto, R K; Mangeol, D J J; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L M; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Nicholson, H; Cavallo, N; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; LoSecco, J M; Allmendinger, T; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonian, R; Wong, Q K; Brau, J E; Frey, R; Igonkina, O; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; La Vaissière, C de; Del Buono, L; Hamon, O; John, M J J; Leruste, P; Malcles, J; Ocariz, J; Pivk, M; Roos, L; T'Jampens, S; Therin, G; Manfredi, P F; Re, V; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martínez-Vidal, F; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lau, Y P; Lü, C; Miftakov, V; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Safai-Tehrani, F; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B J; Geddes, N I; Gopal, G P; Olaiya, E O; Aleksan, Roy; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P F; Hamel de Monchenault, G; Kozanecki, Witold; Legendre, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yéche, C; Zito, M; Purohit, M V; Weidemann, A W; Wilson, J R; Yumiceva, F X; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmüller, O L; Claus, R; Convery, M R; Cristinziani, M; De Nardo, Gallieno; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W M; Elsen, E E; Fan, S; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hast, C; Hrynóva, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Lüth, V; Lynch, H L; Marsiske, H; Messner, R; Müller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Stelzer, J; Su, D; Sullivan, M K; Vavra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Young, C C; Burchat, Patricia R; Edwards, A J; Meyer, T I; Petersen, B A; Roat, C; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bóna, M; Gallo, F; Gamba, D; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vuagnin, G; Panvini, R S; Banerjee, Sw; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R V; Roney, J M; Sobie, R J; Band, H R; Cheng, B; Dasu, S; Datta, M; Eichenbaum, A M; Graham, M; Hollar, J J; Johnson, J R; Kutter, P E; Li, H; Liu, R; Mihályi, A; Mohapatra, A K; Pan, Y; Prepost, R; Tan, P; Von Wimmersperg-Töller, J H; Wu, J; Wu, S L; Yu, Z; Greene, M G; Neal, H

    2004-01-01

    A preliminary measurement of the branching fraction of the tau- -> 3h-2h+nu decay (h= pi, K$) with the BaBar detector is found to be {8.52 +/- 0.09 +/- 0.40} x 10E-4, where the first error is statistical and the second is systematic. The data show evidence that the rho resonance plays a strong role in the decay of the tau lepton to five charged hadrons.

  17. Investigation of the $^{8}$Li($^{2}$H,p)$^{9}$Li Reaction at REX-ISOLDE

    2002-01-01

    We propose to investigate the $^{8}$Li($^{2}$H,p )$^{9}$Li reaction at REX-ISOLDE. The main aim is to test a recently found discrepancy in extracted spectroscopic factors for this reaction. As a byproduct we will obtain improved data relevant for predictions of the $^{8}$Li(n,$\\gamma$)$^{9}$Li rate in inhomogeneous nucleosynthesis. For the full experiment including beam tuning and background measurements we ask for 13 shifts.

  18. Cross sections for H(2p) formation in slow He{sup 2+}-H collisions

    Higgins, D.P.; Geddes, J.; McCullough, R.W. [The Queen`s Univ. of Belfast (United Kingdom)] [and others

    1994-12-31

    A crossed beam method, previously developed in this laboratory, has been used to study H(2p) formation in He{sup 2+}-H collision by observing the spontaneous emission of Lyman alpha radiation. Measurements at energies below 8 keV amu{sup {minus}1} usefully extend previous higher energy data into an energy range where theoretical predictions are markedly different and exhibit interesting structures which reflect the complexity of the excitation mechanism.

  19. 1H and 2H NMR study in paramagnetic solutions of Eu3+ nitrate

    The dependence of the spin-lattice rate(1/T1) of 1H and 2H nuclei for the 2.1 T magnetic field of the concentration (from 0.1 to 2.75 mol) of Eu3+ paramagnetic ions in the range from 263 K to 373 K is presented . Also the NMRD profield for the frecuency range from 0.1 to 500 Mhz is showed

  20. 4-[(2H-Tetra­zol-2-yl)meth­yl]benzonitrile

    Xing, Zheng; Qu, Zhi-Rong

    2008-01-01

    The title compound, C9H7N5, was synthesized by reaction of 4-(bromomethyl)benzonitrile and 2H-tetrazole in the presence of KOH. The relative orientation of the planar tetra­zole ring and the methyl­benzonitrile moiety is (−)-anti­clinal. The crystal packing is dominated by van der Waals inter­actions.

  1. [2H26]-1-epi-Cubenol, a completely deuterated natural product from Streptomyces griseus

    Christian A. Citron; Dickschat, Jeroen S.

    2013-01-01

    During growth on fully deuterated medium the volatile terpene [2H26]-1-epi-cubenol was released by the actinomycete Streptomyces griseus. This compound represents the first completely deuterated terpene obtained by fermentation. Despite a few previous reports in the literature the operability of this approach to fully deuterated compounds is still surprising, because the strong kinetic isotope effect of deuterium is known to slow down all metabolic processes in living organisms. Potential app...

  2. SAS2H: The SCALE-4 analysis sequence for LWR fuel depletion

    The primary use of the SAS2H control module of SCALE (Standardized Computer Analyses for Licensing Evaluation) is for fuel depletion analyses of light-water-reactor (LWR) fuel. Spent fuel characteristics such as radiation sources, heat generation sources, and isotopic concentrations can be computed within SCALE using the SAS2 control module. At each time step, the SAS2 sequence performs a radiation transport analysis (via XSDRNPM-S) to obtain appropriate cross sections and spectral parameters for an ORIGEN-S point-depletion analysis. Each ORIGEN-S case produces the burnup-dependent fuel composition to be used in the next spectral calculation. A final ORIGEN-S case is used to perform the complete depletion/decay analysis using the burnup-dependent cross sections. A significantly enhanced version of the SAS2 control module, which is denoted as SAS2H, has been made available with the release of SCALE-4. The techniques used by SAS2H are presented in this paper along with a discussion of some recent validation/verification efforts

  3. Liquid water on Mars - An energy balance climate model for CO2/H2O atmospheres

    Hoffert, M. I.; Callegari, A. J.; Hsieh, C. T.; Ziegler, W.

    1981-01-01

    A simple climatic model is developed for a Mars atmosphere containing CO2 and sufficient liquid water to account for the observed hydrologic surface features by the existence of a CO2/H2O greenhouse effect. A latitude-resolved climate model originally devised for terrestrial climate studies is applied to Martian conditions, with the difference between absorbed solar flux and emitted long-wave flux to space per unit area attributed to the divergence of the meridional heat flux and the poleward heat flux assumed to equal the atmospheric eddy heat flux. The global mean energy balance is calculated as a function of atmospheric pressure to assess the CO2/H2O greenhouse liquid water hypothesis, and some latitude-resolved cases are examined in detail in order to clarify the role of atmospheric transport and temperature-albedo feedback. It is shown that the combined CO2/H2O greenhouse at plausible early surface pressures may account for climates hot enough to support a hydrological cycle and running water at present-day insolation and visible albedo levels.

  4. The application of 2H2O to measure skeletal muscle protein synthesis

    Fluckey James D

    2010-04-01

    Full Text Available Abstract Skeletal muscle protein synthesis has generally been determined by the precursor:product labeling approach using labeled amino acids (e.g., [13C]leucine or [13C]-, [15N]-, or [2H]phenylalanine as the tracers. Although reliable for determining rates of protein synthesis, this methodological approach requires experiments to be conducted in a controlled environment, and as a result, has limited our understanding of muscle protein renewal under free-living conditions over extended periods of time (i.e., integrative/cumulative assessments. An alternative tracer, 2H2O, has been successfully used to measure rates of muscle protein synthesis in mice, rats, fish and humans. Moreover, perturbations such as feeding and exercise have been included in these measurements without exclusion of common environmental and biological factors. In this review, we discuss the principle behind using 2H2O to measure muscle protein synthesis and highlight recent investigations that have examined the effects of feeding and exercise. The framework provided in this review should assist muscle biologists in designing experiments that advance our understanding of conditions in which anabolism is altered (e.g., exercise, feeding, growth, debilitating and metabolic pathologies.

  5. Modeling studies of the chemical vapor deposition of boron films from B 2H 6

    Lamborn, Daniel R.; Snyder, David W.; Xi, X. X.; Redwing, Joan M.

    2007-02-01

    The effect of growth conditions on the chemical vapor deposition of boron thin films from diborane (B 2H 6) was investigated using a combination of experimental studies and computational fluid dynamics-based reactor modeling. A multi-physics computational model was developed to simulate the thermal-fluid environment in the reactor. The proposed chemistry model incorporated into the simulations includes gas-phase decomposition and formation of B 2H 6 and surface adsorption and reaction of borane (BH 3). The model accurately predicts the experimentally measured temperature and partial pressure dependence of the boron growth rate using the sticking coefficient of BH 3 on the growth surface as the only adjustable parameter in the calculations. The results indicate that at lower growth temperatures (500 °C) the growth rate is limited by mass transfer of BH 3 to the substrate surface. The studies of boron thin film growth are relevant to the deposition of superconducting MgB 2 thin films, in which B 2H 6 is used as the boron precursor.

  6. NMR resonance splitting of urea in stretched hydrogels: proton exchange and (1)H/(2)H isotopologues.

    Kuchel, Philip W; Naumann, Christoph; Chapman, Bogdan E; Shishmarev, Dmitry; Håkansson, Pär; Bacskay, George; Hush, Noel S

    2014-10-01

    Urea at ∼12 M in concentrated gelatin gel, that was stretched, gave (1)H and (2)H NMR spectral splitting patterns that varied in a predictable way with changes in the relative proportions of (1)H2O and (2)H2O in the medium. This required consideration of the combinatorics of the two amide groups in urea that have a total of four protonation/deuteration sites giving rise to 16 different isotopologues, if all the atoms were separately identifiable. The rate constant that characterized the exchange of the protons with water was estimated by back-transformation analysis of 2D-EXSY spectra. There was no (1)H NMR spectral evidence that the chiral gelatin medium had caused in-equivalence in the protons bonded to each amide nitrogen atom. The spectral splitting patterns in (1)H and (2)H NMR spectra were accounted for by intra-molecular scalar and dipolar interactions, and quadrupolar interactions with the electric field gradients of the gelatin matrix, respectively. PMID:25241007

  7. Modelling of c-C2H4O formation on grain surfaces

    Occhiogrosso, A; Ward, M D; Price, S D

    2012-01-01

    Despite its potential reactivity due to ring strain, ethylene oxide (c-C2H4O) is a complex molecule that seems to be stable under the physical conditions of an interstellar dense core; indeed it has been detected towards several high-mass star forming regions with a column density of the order of 10e13cm-2 (Ikeda et al. 2001). To date, its observational abundances cannot be reproduced by chemical models and this may be due to the significant contribution played by its chemistry on grain surfaces. Recently, Ward and Price (2011) have performed experiments in order to investigate the surface formation of ethylene oxide starting with oxygen atoms and ethylene ice as reactants. We present a chemical model which includes the most recent experimental results from Ward and Price (2011) on the formation of c-C2H4O. We study the influence of the physical parameters of dense cores on the abundances of c-C2H4O. We verify that ethylene oxide can indeed be formed during the cold phase (when the ISM dense cores are formed)...

  8. Angular momentum of the N2H+ cores in the Orion A cloud

    Tatematsu, Ken'ichi; Ohashi, Satoshi; Sanhueza, Patricio; Nguyen Luong, Quang; Umemoto, Tomofumi; Mizuno, Norikazu

    2016-04-01

    We have analyzed the angular momentum of the molecular cloud cores in the Orion A giant molecular cloud observed in the N2H+ J = 1-0 line with the Nobeyama 45 m radio telescope. We have measured the velocity gradient using position-velocity diagrams passing through core centers, and made sinusoidal fits against the position angle. Twenty-seven out of 34 N2H+ cores allowed us to measure the velocity gradient without serious confusion. The derived velocity gradient ranges from 0.5 to 7.8 km s-1 pc-1. We marginally found that the specific angular momentum J/M (against the core radius R) of the Orion N2H+ cores tends to be systematically larger than that of molecular cloud cores in cold dark clouds obtained by Goodman et al., in the J/M-R relation. The ratio β of rotational to gravitational energy is derived to be β = 10-2.3±0.7, and is similar to that obtained for cold dark cloud cores in a consistent definition. The large-scale rotation of the ∫-shaped filament of the Orion A giant molecular cloud does not likely govern the core rotation at smaller scales.

  9. Regulated release of Ca2+ from respiring mitochondria by Ca2+/2H+ antiport.

    Fiskum, G; Lehninger, A L

    1979-07-25

    Simultaneous measurements of oxygen consumption and transmembrane transport of Ca2+, H+, and phosphate show that the efflux of Ca2+ from respiring tightly coupled rat liver mitochondria takes place by an electroneutral Ca2+/2H+ antiport process that is ruthenium red-insensitive and that is regulated by the oxidation-reduction state of the mitochondrial pyridine nucleotides. When mitochondrial pyridine nucleotides are kept in a reduced steady state, the efflux of Ca2+ is inhibited; when they are in an oxidized state, Ca2+ efflux is activated. These processes were demonstrated by allowing phosphate-depleted mitochondria respiring on succinate in the presence of rotenone to take up Ca2+ from the medium. Upon subsequent addition of ruthenium red to block Ca2+ transport via the electrophoretic influx pathway, and acetoacetate, to bring mitochondrial pyridine nucleotides into the oxidized state, Ca2+ efflux and H+ influx ensued. The observed H+ influx/Ca2+ efflux ratio was close to the value 2.0 predicted for the operation of an electrically neutral Ca2+/2H+ antiport process. PMID:36390

  10. Laboratory IR Studies and Astrophysical Implications of C2H2-Containing Binary Ices

    Knez, C.; Moore, M. H.; Ferrante, R. F.; Hudson, R. L.

    2012-04-01

    Studies of molecular hot cores and protostellar environments have shown that the observed abundance of gas-phase acetylene (C2H2) cannot be matched by chemical models without the inclusion of C2H2 molecules subliming from icy grain mantles. Searches for infrared (IR) spectral features of solid-phase acetylene are under way, but few laboratory reference spectra of C2H2 in icy mixtures, which are needed for spectral fits to observational data, have been published. Here, we report a systematic study of the IR spectra of condensed-phase pure acetylene and acetylene in ices dominated by carbon monoxide (CO), carbon dioxide (CO2), methane (CH4), and water (H2O). We present new spectral data for these ices, including band positions and intrinsic band strengths. For each ice mixture and concentration, we also explore the dependence of acetylene's ν5-band position (743 cm-1, 13.46 μm) and FWHM on temperature. Our results show that the ν5 feature is much more cleanly resolved in ices dominated by non-polar and low-polarity molecules, specifically CO, CO2, and CH4, than in mixtures dominated by H2O-ice. We compare our laboratory ice spectra with observations of a quiescent region in Serpens.

  11. LABORATORY IR STUDIES AND ASTROPHYSICAL IMPLICATIONS OF C2H2-CONTAINING BINARY ICES

    Studies of molecular hot cores and protostellar environments have shown that the observed abundance of gas-phase acetylene (C2H2) cannot be matched by chemical models without the inclusion of C2H2 molecules subliming from icy grain mantles. Searches for infrared (IR) spectral features of solid-phase acetylene are under way, but few laboratory reference spectra of C2H2 in icy mixtures, which are needed for spectral fits to observational data, have been published. Here, we report a systematic study of the IR spectra of condensed-phase pure acetylene and acetylene in ices dominated by carbon monoxide (CO), carbon dioxide (CO2), methane (CH4), and water (H2O). We present new spectral data for these ices, including band positions and intrinsic band strengths. For each ice mixture and concentration, we also explore the dependence of acetylene's ν5-band position (743 cm–1, 13.46 μm) and FWHM on temperature. Our results show that the ν5 feature is much more cleanly resolved in ices dominated by non-polar and low-polarity molecules, specifically CO, CO2, and CH4, than in mixtures dominated by H2O-ice. We compare our laboratory ice spectra with observations of a quiescent region in Serpens.

  12. Preparation and Molecular Structure of (SCZ)(TNPG)·2H2O

    CHEN Hong-Yan; ZHANG Tong-Lai; ZHANG Jian-Guo

    2005-01-01

    The (SCZ)(TNPG)·2H2O prepared by mixing semicarbazide (SCZ) and trinitrophloroglucinol (TNPG) was characterized by elemental analysis and IR measurement, and its crystal structure was determined by X-ray single-crystal diffraction analysis.The crystal belongs to triclinic,0.93966(19), c = 1.1925(2) nm, α = 67.48(3), β = 77.56(3), γ = 78.93(3)°, V = 0.6908(2) nm3, Z = 2,Dc = 1.789 g/cm3, Mr = 373.23, F(000) = 384, S = 0.999 andt(MoKα) = 0.172 mm-1.The final R and wR are 0.0394 and 0.1057 for 1724 observed reflections with I > 2σ(I).It is concluded that (SCZ)(TNPG) 2H2O is an ionic compound composed of a cation SCZ+, an anion TNPG- and two water molecules.The TNPG anion and SCZ+ cation are bonded together by electrostatic attraction and hydrogen bonds, and the compound structure is stable.The thermal decomposition of (SCZ)(TNPG) 2H2O was studied by using TG-DTG and DSC techniques with a heating rate of 10 ℃/min, showing the compound contains one endothermic process of dehydrating stage and two intensive exothermic decomposition stages.The enthalpy of exothermic decomposition reaction is 452.31 kJ/mol.

  13. Angular Momentum of the N2H+ Cores in the Orion A Cloud

    Tatematsu, Ken'ichi; Sanhueza, Patricio; Luong, Quang Nguyen; Umemoto, Tomofumi; Mizuno, Norikazu

    2016-01-01

    We have analyzed the angular momentum of the molecular cloud cores in the Orion A giant molecular cloud observed in the N2H+ J = 1-0 line with the Nobeyama 45 m radio telescope. We have measured the velocity gradient using position velocity diagrams passing through core centers, and made sinusoidal fitting against the position angle. 27 out of 34 N2H+ cores allowed us to measure the velocity gradient without serious confusion. The derived velocity gradient ranges from 0.5 to 7.8 km/s/pc. We marginally found that the specific angular momentum J/M (against the core radius R) of the Orion N2H+ cores tends to be systematically larger than that of molecular cloud cores in cold dark clouds obtained by Goodman et al., in the J/M-R relation. The ratio beta of rotational to gravitational energy is derived to be beta = 10^{-2.3+/-0.7}, and is similar to that obtained for cold dark cloud cores in a consistent definition. The large-scale rotation of the integral-shaped filament of the Orion A giant molecular cloud does n...

  14. Peak effect studies in single crystals CeRu2 and 2H-NbS2

    A A Tulapurkar; A K Grover; S Ramakrishnan; A Niazi; A K Rastogi

    2002-05-01

    We have studied the peak effect (PE) phenomenon in single crystals of weakly pinned superconductors CeRu2 and 2H-NbS2. 2H-NbS2 is iso-structural and iso-electronic to 2H-NbSe2, whose similarity with CeRu2 as regards the PE representing the order-to-disorder transformation of the flux line lattice was claimed some time ago. We report on the step change in equilibrium magnetization across the peak effect in CeRu2. We also present the vortex phase diagram of 2H-NbS2 obtained from the magnetization data, and compare the PE phenomenon in 2H-NbS2 and 2H-NbSe2.

  15. Gas-phase CO2, C2H2, and HCN toward Orion-KL

    Boonman, A. M. S.; van Dishoeck, E. F.; Lahuis, F.; Doty, S. D.; Wright, C. M.; Rosenthal, D.

    2003-03-01

    The infrared spectra toward Orion-IRc2, Peak 1 and Peak 2 in the 13.5-15.5 mu m wavelength range are presented, obtained with the Short Wavelength Spectrometer on board the Infrared Space Observatory. The spectra show absorption and emission features of the vibration-rotation bands of gas-phase CO2, HCN, and C2H2, respectively. Toward the deeply embedded massive young stellar object IRc2 all three bands appear in absorption, while toward the shocked region Peak 2 CO2, HCN, and C2H2 are seen in emission. Toward Peak 1 only CO2 has been detected in emission. Analysis of these bands shows that the absorption features toward IRc2 are characterized by excitation temperatures of ~ 175-275 K, which can be explained by an origin in the shocked plateau gas. HCN and C2H2 are only seen in absorption in the direction of IRc2, whereas the CO2 absorption is probably more widespread. The CO2 emission toward Peak 1 and 2 is best explained with excitation by infrared radiation from dust mixed with the gas in the warm component of the shock. The similarity of the CO2 emission and absorption line shapes toward IRc2, Peak 1 and Peak 2 suggests that the CO2 is located in the warm component of the shock (T ~ 200 K) toward all three positions. The CO2 abundances of ~ 10-8 for Peak 1 and 2, and of a few times 10-7 toward IRc2 can be explained by grain mantle evaporation and/or reformation in the gas-phase after destruction by the shock. The HCN and C2H2 emission detected toward Peak 2 is narrower (T ~ 50-150 K) and originates either in the warm component of the shock or in the extended ridge. In the case of an origin in the warm component of the shock, the low HCN and C2H2 abundances of ~ 10-9 suggest that they are destroyed by the shock or have only been in the warm gas for a short time (t Germany, The Netherlands and the UK) and with the participation of ISAS and NASA.

  16. Anti-sense RNA Inhibits the Expression of Synaptotagmin Ⅱ in RBL-2H3 and Enhances the Exocytosis of Lysosomes in RBL-2H3

    2005-01-01

    The expression of synaptotagmin Ⅱ (Syt2) in RBL-2H3 (RBL) and its role during exocytosis of RBL was investigated. The expression of Syt2 in RBL was detected by western blot and Syt2 gene was amplified by PCR. The anti-sense full length Syt2 cDNA expression vector was constructed with pEGFP-N1 and transfected into RBL by electroporation, and stable transfectants were selected by using G418. To analyze the role of Syt2 during exocytosis of RBL, the release of cathepsin D was assayed by immunoblotting. The results showed that Syt2 was expressed in RBL.The anti-sense expression vector pEGFP-N1-Syt2-AS was constructed and the sequence of insertion was completely consistent with rat Syt2 (accession number in GeneBank: NM012665). The stable transfectants (RBL-Syt2-AS) were obtained. Western blot showed that RBL-Syt2-AS expressed a lower level of Syt2 (8 % and 10 % of control cells), indicating that the expression of Syt2 in RBLSyt2-AS was markedly down-regulated by anti-RNA. Compared with control, the release of cathepsin D by RBL-Syt2-AS was increased. It was concluded that Syt2 expressed in RBL and could inhibit exocytosis of lysosomes in RBL.

  17. Ethylene glycol causes acyl chain disordering in liquid-crystalline, unsaturated phospholipid model membranes, as measured by 2H NMR

    NICOLAY K; Smaal, E B; de Kruijff, B.

    1986-01-01

    2H NMR has been used to probe the effects of ethylene glycol at the level of the acyl chains in liposomes prepared from dioleoylphosphatidic acid or dioleoylphosphatidylcholine, labeled with 2H at the 11-position of both oleic acid chains. Increasing concentrations of ethylene glycol lead to a proportional and substantial decrease in the quadrupolar splittings, measured from the 2H NMR spectra of both liposomal systems, indicative of acyl chain disordering.

  18. Ethylene glycol causes acyl chain disordering in liquid-crystalline, unsaturated phospholipid model membranes, as measured by 2H NMR

    2H NMR has been used to probe the effects of ethylene glycol at the level of the acyl chains in liposomes prepared from dioleoylphosphatidic acid or dioleoylphosphatidylcholine, labeled with 2H at the 11-position of both oleic acid chains. Increasing concentrations of ethylene glycol lead to a proportional and substantial decrease in the quadrupolar splittings, measured from the 2H NMR spectra of both liposomal system, indicative of acyl chain disordering. (Auth.)

  19. Synthesis of 4-Triazolylamino- and 4-Benzothiazolylamino-3-nitro-2H-[1]-Benzopyran-2-ones and their Antimicrobial Activity

    Ramiz Hoti; Aferdita Nura-Lama; Gjyle Mulliqi-Osmani; Naser Troni; Fatbardh Gashi; Hamit Ismaili; Veprim Thaci

    2014-01-01

    Novel substituted benzopyran-2-one derivatives were synthesized by catalytic condensation reactions under reflux conditions. 4-(1,2,4-Triazolyl-3-amino)-3-nitro-2H-[1]-benzopyran-2-ones 4(a-b) were synthesized by condensation of 4-chloro-3-nitro-2H-[1]-benzopyran-2-one (2) and corresponding 3-aminotriazoles 3(a-b). 4-(4’-methoxy-2-benzothiazolylamino)-3-nitro-2H-[1]-benzopyran-2-one (4c), 4-(6’-nitro-2-benzothiazolylamino)-3-nitro-2H-[1]-benzopyiran-2-one (4d) and 4-(6’-fluoro-2-benzothiazoly...

  20. The hnRNP 2H9 gene, which is involved in the splicing reaction, is a multiply spliced gene

    Honoré, B

    2000-01-01

    The hnRNP 2H9 gene products are involved in the splicing process and participate in early heat shock-induced splicing arrest. By combining low/high stringency hybridisation, database search, Northern and Western blotting it is shown that the gene is alternatively spliced into at least six...... transcripts: hnRNPs 2H9, 2H9A, 2H9B, 2H9C, 2H9D and 2H9E predicting proteins containing 346, 331, 297, 215, 145 and 139 amino acids, respectively. The hnRNP 2H9A cDNA sequence was used to obtain a genomic BAC clone and the structure of the hnRNP 2H9 gene was revealed by sequencing two subclones together...... indicates that the alternatively spliced transcripts give rise to different sets and levels of proteins expressed among various human cells and tissues. Due to their great structural variations the different proteins may thus possess different functions in the splicing reaction. Udgivelsesdato: 2000-Jun-21...

  1. Plasma spot welding of ferritic stainless steels

    Plasma spot wedding of ferritic stainless steels studied. The study was focused on welding parameters, plasma and shieldings and the optimum welding equipment. Plasma-spot welded overlap joints on a 0.8 mm thick ferritic stainless steel sheet were subjected to a visual examination and mechanical testing in terms of tension-shear strength. Several macro specimens were prepared Plasma spot welding is suitable to use the same gas as shielding gas and as plasma gas , i. e. a 98% Ar/2% H2 gas mixture. Tension-shear strength of plasma-spot welded joint was compared to that of resistance sport welded joints. It was found that the resistance welded joints withstand a somewhat stronger load than the plasma welded joints due to a large weld sport diameter of the former. Strength of both types of welded joints is approximately the same. (Author) 32 refs

  2. Volume-discharge formed in SF6 and C2H6 mixtures without preionization

    Zhang, Ge; Ke, Changjun; Zhang, Shujuan

    2014-11-01

    A new approach to obtain glow discharge in working mixtures of non-chain HF laser has been brought forward. The most advantage of the approach is without pre-ionization, so the contamination of pre-ionization will not happen and the laser equipment is compact and simple. It is found, if the cathode surface is equally rough, we can obtain uniform volume-discharge in SF6 mixtures without any pre-ionization, and dispense with uniform electric field electrode profile. The form of Self-Sustained Volume Discharge (SSVD) is a Self-Initiated Volume Discharge (SIVD). We show here the possibility of obtaining SIVD with a uniform energy deposition in a system of electrodes with non-uniform electric field. Experiments show that, with rough cathode and even anode, a volume discharge is forming in non-uniform electric-field without pre-ionization in SF6 and C2H6 mixtures. At the beginning of the discharge, many diffuse channels attached to bright circular cathode spots, then, diverge towards the anode, with the channels overlapping, form a spatially uniform glow discharge. SIVD has been performed at a total mixture pressure up to 8kPa and energy deposition up to 200J/l. We also report measurements of the V-I characteristics of SIVD with SF6 and C2H6 mixtures at pressure up to about 8kPa. The experimental results indicate that SSVD in SF6 and C2H6 mixtures develops in the form of SIVD is promising for creation of high energy and pulse-periodic HF laser.

  3. Spectroscopic Line Parameters in the Infrared Bands of CH3CN and C2H6

    Devi, V. Malathy

    2010-10-01

    In this paper, measurements of critical spectroscopic line parameters such as positions, absolute intensities and pressure broadened (self- and N2) half-width coefficients for transitions in the ν4 band of CH3CN (acetonitile, ethanenitrile, methyl cyanide) and the ν9 band of C2H6 (ethane) are presented. CH3CN has been measured by remote sensing in the earth's atmosphere, in comets and in interstellar molecular clouds. It is also a constituent in the atmospheres of Titan, Saturn's largest moon. Likewise, C2H6 is also an important constituent in the atmosphere of earth, the giant planets and comets. The 12- μm(˜720-850 cm-1) emission features of this molecule have been observed in spectra from outer solar system bodies of Jupiter, Saturn, Neptune and Titan. Because of their importance in remote sensing measurements, we recently recorded and analyzed a large number of laboratory infrared absorption spectra of pure and N2-broadened spectra of both these molecular bands. Spectra used in these analyses were recorded using either the Bruker IFS 125HR or the Bruker IFS 120HR FTS located at the Pacific Northwest National Laboratory (PNNL), in Richland Washington. To retrieve the various spectral line parameters, a multispectrum nonlinear least squares fitting algorithm was employed and all spectra belonging to each band were fitted simultaneously. Using this fitting technique, the same spectral regions from multiple spectra were fit all at once to maximize the accuracy of the retrieved parameters. The results obtained from present analyses are briefly discussed. In the case of C2H6 both room- and low temperature (˜210-296 K) spectra were recorded, but results from analyzing only room-temperature spectra will be discussed in this work.

  4. Validation of SCALE (SAS2H) Isotopic Predictions for BWR Spent Fuel

    Hermann, O.W.

    1998-01-01

    Thirty spent fuel samples obtained from boiling-water-reactor (BWR) fuel pins have been modeled at Oak Ridge National Laboratory using the SAS2H sequence of the SCALE code system. The SAS2H sequence uses transport methods combined with the depletion and decay capabilities of the ORIGEN-S code to estimate the isotopic composition of fuel as a function of its burnup history. Results of these calculations are compared with chemical assay measurements of spent fuel inventories for each sample. Results show reasonable agreement between measured and predicted isotopic concentrations for important actinides; however, little data are available for most fission products considered to be important for spent fuel concerns (e.g., burnup credit, shielding, source-term calculations, etc.). This work is a follow-up to earlier works that studied the ability to predict spent fuel compositions in pressurized-water-reactor (PWR) fuel pins. Biases and uncertainties associated with BWR isotopic predictions are found to be larger than those of PWR calculations. Such behavior is expected, as the operation of a BWR is significantly more complex than that of a PWR plant, and in general the design of a BWR has a more heterogeneous configuration than that of a PWR. Nevertheless, this work shows that the simple models employed using SAS2H to represent such complexities result in agreement to within 5% (and often less than 1%) or less for most nuclides important for spent fuel applications. On the other hand, however, the set of fuel samples analyzed represent a small subset of the BWR fuel population, and results reported herein may not be representative of the full population of BWR spent fuel.

  5. Quinolone-1-(2H)-ones as hedgehog signalling pathway inhibitors.

    Trinh, Trieu N; McLaughlin, Eileen A; Abdel-Hamid, Mohammed K; Gordon, Christopher P; Bernstein, Ilana R; Pye, Victoria; Cossar, Peter; Sakoff, Jennette A; McCluskey, Adam

    2016-07-14

    A series of quinolone-2-(1H)-ones derived from the Ugi-Knoevenagel three- and four-component reaction were prepared exhibiting low micromolar cytotoxicity against a panel of eight human cancer cell lines known to possess the Hedgehog Signalling Pathway (HSP) components, as well as the seminoma TCAM-2 cell line. A focused SAR study was conducted and revealed core characteristics of the quinolone-2-(1H)-ones required for cytotoxicity. These requirements included a C3-tethered indole moiety, an indole C5-methyl moiety, an aliphatic tail or an ester, as well as an additional aromatic moiety. Further investigation in the SAG-activated Shh-LIGHT2 cell line with the most active analogues: 2-(3-cyano-2-oxo-4-phenylquinolin-1(2H)-yl)-2-(1-methyl-1H-indol-3-yl)-N-(pentan-2-yl)acetamide (5), 2-(3-cyano-2-oxo-4-phenylquinolin-1(2H)-yl)-2-(5-methyl-1H-indol-3-yl)-N-(pentan-2-yl)acetamide (23) and ethyl (2-(3-cyano-2-oxo-4-phenylquinolin-1(2H)-yl)-2-(5-methyl-1H-indol-3-yl)acetyl)glycinate (24) demonstrated a down regulation of the HSP via a reduction in Gli expression, and in the mRNA levels of Ptch1 and Gli2. Analogues 5, 23 and 24 returned in cell inhibition values of 11.6, 2.9 and 3.1 μM, respectively, making this new HSP-inhibitor pharmacophore amongst the most potent non-Smo targeted inhibitors thus far reported. PMID:27272335

  6. Thermal neutron capture cross sections for 16,171,18O and 2H

    Firestone, R. B.; Revay, Zs.

    2016-04-01

    Thermal neutron capture γ -ray spectra for 16,17,18O and 2H have been measured with guided cold neutron beams from the Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II) reactor and the Budapest Research Reactor (BRR) on natural and O,1817 enriched D2O targets. Complete neutron capture γ -ray decay schemes for the 16,17,18O(n ,γ ) reactions were measured. Absolute transition probabilities were determined for each reaction by a least-squares fit of the γ -ray intensities to the decay schemes after accounting for the contribution from internal conversion. The transition probability for the 870.76-keV γ ray from 16O(n ,γ ) was measured as Pγ(871 )=96.6 ±0.5 % and the thermal neutron cross section for this γ ray was determined as 0.164 ±0.003 mb by internal standardization with multiple targets containing oxygen and stoichiometric quantities of hydrogen, nitrogen, and carbon whose γ -ray cross sections were previously standardized. The γ -ray cross sections for the O,1817(n ,γ ) and 2H(n ,γ ) reactions were then determined relative to the 870.76-keV γ -ray cross section after accounting for the isotopic abundances in the targets. We determined the following total radiative thermal neutron cross sections for each isotope from the γ -ray cross sections and transition probabilities; σ0(16O )=0.170 ±0.003 mb; σ0(17O )=0.67 ±0.07 mb; σ0(18O )=0.141 ±0.006 mb; and σ0(2H )=0.489 ±0.006 mb.

  7. First-principles calculations of the magnetism of Fe$_2$O$_2$H$_2$

    Stolbov, Sergey; Klemm, Richard A.; Rahman, Talat S.

    2005-01-01

    By expanding the wave function in plane waves, we use the pseudopotential method of density functional theory within the generalized gradient approximation to calculate the effective magnetic coupling energies of the S=5/2 spins in the Fe2 dimer, approximated as Fe$_2$O$_2$H$_2$. Setting the Fe-O bond length at the value corresponding to the minimum total energy, we find the difference in antiferromagnetic and ferromagnetic exchange energies as a function of the Fe-O-Fe bond angle $\\theta$. T...

  8. Nonfactorized Calculation of the Process 3He(e,e'p)2H at Medium Energies

    The exclusive process 3He(e,e'p)2H has been analyzed by a nonfactorized and parameter-free approach based upon realistic few-body wave functions corresponding to the AV18 interaction and treating the rescattering of the struck nucleon within a generalized eikonal approximation. The results of our calculations, compared with recent JLab experimental data, show that the left-right asymmetry exhibits a clear dependence upon the final state interaction demonstrating the breaking down of the factorization approximation at 'negative' and large (> or approx. 300 MeV/c) values of the missing momentum

  9. Relativistic model of 2p-2h meson exchange currents in (anti)neutrino scattering

    Simo, I Ruiz; Barbaro, M B; De Pace, A; Caballero, J A; Donnelly, T W

    2016-01-01

    We develop a model of relativistic, charged meson-exchange currents (MEC) for neutrino-nucleus interactions. The two-body current is the sum of seagull, pion-in-flight, pion-pole and $\\Delta$-pole operators. These operators are obtained from the weak pion-production amplitudes for the nucleon derived in the non-linear $\\sigma$-model together with weak excitation of the $\\Delta(1232)$ resonance and its subsequent decay into $N\\pi$. With these currents we compute the five 2p-2h response functions contributing to $(\

  10. 3-(3,4-Dihydroxyphenyl-8-hydroxy-2H-chromen-2-one

    Ivan Svinyarov

    2015-10-01

    Full Text Available We report a novel protocol for the synthesis of 3-(3,4-dihydroxyphenyl-8-hydroxy-2H-chromen-2-one via demethylation/delactonization/elimination/lactonization/ decarboxylation domino reaction sequence of diastereomeric mixture of cis- and trans-3-(2,3-dimethoxyphenyl-6,7-dimethoxy-1-oxoisochroman-4-carboxylic acids in boiling HBr/AcOH. The structure of the target compound was established for the first time by means of spectral methods such as 1H-, 13C-, DEPT-135-NMR, IR and HRMS.

  11. High purity H-2/H2O/Ni/SZ electrodes at 500 degrees C

    Høgh, Jens Valdemar Thorvald; Hansen, Karin Vels; Norrman, Kion; Chorkendorff, Ib; Jacobsen, Torben; Mogensen, Mogens

    2013-01-01

    stabilized zirconia (SZ) with 10,13 and 18 mol% yttria and one with 6 mol% scandia plus 4 mol% yttria were studied at open circuit voltage at 400-500 degrees C in mixtures of H-2/H2O over 46 days. The polarization resistances (R-p) for all samples increased significantly during the first 10-20 days at 500......The performance of SOFC (solid oxide fuel cell) anodes is influenced negatively by impurities. In the present study segregation of impurities is minimized by using high purity materials at relatively low temperatures to prevent fast segregation. Ni point electrodes on polished single crystals of...

  12. Transcriptional Silencing in the Imprinted Igf2-H19 Loci: The Mystique of Epigenetics

    Ginjala, Vasudeva

    2002-01-01

    Genomic imprinting marks a subset of autosomal loci expressed in parent of origin-dependent monoallelic expression in a non-Mendelian fashion. To restore totipotency and to reset the imprint according to the sex of the individual, the mark must be erased during germline development. The imprinted Igf2-H19 loci located distally on chromosome 7 in mouse and 11p15.5 in human, share common regulatory elements that regulate differential expression. Where the H19 is silenced when paternally inherit...

  13. Characterization Results for the 2014 HTF 3H & 2H Evaporator Overhead Samples

    Washington, A. [Savannah River Site (SRS), Aiken, SC (United States)

    2015-05-11

    This report tabulates the radiochemical analysis of the 3H and 2H evaporator overhead samples for 137Cs, 90Sr, and 129I to meet the requirements in the Effluent Treatment Project (ETP) Waste Acceptance Criteria (WAC) (rev. 6). This report identifies the sample receipt date, preparation method, and analysis performed in the accumulation of the listed values. All data was found to be within the ETP WAC (rev. 6) specification for the Waste Water Collection Tanks (WWCT).

  14. Dissolution of plutonium metal in HNO3-N2H4-KF

    Plutonium metal dissolves in HNO3-N2H4.HNO3-KF solution to yield a Pu3+ solution without an accompanying precipitation of plutonium oxide solids. The reaction evolves less than 0.2 mole of gas per mole of plutonium dissolved; the gas contains only 3% H2. About 10-3 moles of HN3 are produced per mole of plutonium dissolved. Optimum conditions for dissolving both alpha-phase and delta-phase plutonium metal were developed. Possible applications are to the recovery of plutonium metal or the processing of irradiated plutonium metal and alloys

  15. Synthesis and properties of [(DMSO)2H][Ru(DMSO)2Br4

    The ruthenium (3) [(DMSO)2H][Ru(DMSO)2Br4] complex, structure of which is defined on the basis of the chemical analysis, IRS and ESP data, is synthesized by interaction of ruthenium tribromide with DMSO. The compound is labile in the solutions, in the DMSO solutions it transforms into the ruthenium (2) dimethylsulfoxide complexes, in the HBr solutions occurs fast deoxygeneration of coordinated DMSO and formation of the ruthenium(3) dimethylsulfide complexes, which thereafter are transformed into [RuBr6]3- ion. The ruthenium(3) dimethylsulfide is formed by interaction of ruthenium with DMSO and in thepresence of HBr at the temperature of 130 deg C

  16. CO2-H2O和CO2-H2O-NaCl体系的相平衡研究进展%Progress in the Study on the Phase Equilibria of the CO2-H2O and CO2-H2O-NaCl Systems

    吉远辉; 吉晓燕; 冯新; 刘畅; 吕玲红; 陆小华

    2007-01-01

    To study the feasibility of CO2 geological sequestration, it is needed to understand the complicated multiple-phase equilibrium and the densities of aqueous solution with CO2 and multi-ions under wide geological conditions (273.15 473.15K, 0-60MPa), which are also essential for designing separation equipments in chemical or oil-related industries.For this purpose, studies on the relevant phase equilibria and densities are reviewed and analyzed and the method to improve or modify the existing model is suggested in order to obtain more reliable predictions in a wide temperature and pressure range.Besides, three different models (the electrolyte non random twoliquid (ELECNRTL), the electrolyte NRTL combining with Helgeson model (ENRTL-HG), Pitzer activity coefficient model combining with Helgeson model (PITZ-HG) are used to calculate the vapor-liquid phase equilibrium of CO2-H2O and CO2-H2O-NaCl systems.For CO2-H2O system, the calculation results agree with the experimental data very well at low and medium pressure (0-20MPa), but there are great discrepancies above 20MPa.For the water content at 473.15K, the calculated results agree with the experimental data quite well.For the CO2-H2O-NaCl system, the PITZ-HG model show better results than ELECNRTL and ENRTL-HG models at the NaCI concentration of 0.52mol·L-1.Bur for the NaCl concentration of 3.997mol·L-1,using the ELECNRTL and ENRTL-HG models gives better results than using the PITZ-HG model.It is shown that available experimental data and the thermodynamic calculations can satisfy the needs of the calculation of the sequestration capacity in the temperature and pressure range for disposal of CO2 in deep saline aquifers.More experimental data and more accurate thermodynamic calculations are needed in high temperature and pressure ranges (above 398.15K and 31.5MPa).

  17. Measurement of Magnetization Curve and Magnetic Relaxation for 2H-NbSe2 Crystals

    Zhang Ning; Liu Hai-lin; Yu Zhu-xing; Xiong Rui; Shi Jing

    2004-01-01

    The characteristics of electronic transport properties: behaviors of magnetization curve and magnetic relaxation of a typical normal superconductor 2H-NbSe2 are investigated. The results show that TCand ΔTC of the samples are 7.2,0.18 K, indicating that superconducting energy gap at zero temperature is 1.1 meV. No fish tail shape is found in the magnetization curves at several temperatures. The relationship between remnant magnetic moment and time reveals that the magnetic flux creep of the sample agrees with the Kim-Anderson thermal activation model with the relaxation rate S=0.000 36 at T=6 K.

  18. Smoothed orientational order profile of lipid bilayers by 2H-nuclear magnetic resonance

    A new method has been developed to determine the complete orientational order profile of lipid bilayers using 2H-NMR. The profile is obtained from a single powder spectrum of a lipid which has a saturated chain fully deuteriated. The smoothed order profile is determined directly from the normalized dePaked spectrum assuming a monotonic decrease of the order along the acyl chain. The oscillatory variations of the order at the beginning of the chain are not described by this method. However the smoothed order profile reveals in a straightforward way the crucial features of the anisotropic order of the bilayer

  19. Thermodynamic study of NaCl-CdCl2-H2O system at 25 deg

    The solubility is studied and water activity is measured in the whole region concentrations of ternary solutions of the NaCl-CdCl2-H2O system at 25 deg by isothermal and isopiestic methods respectively. The solubility isotherm has two branches proper to crystallization of the 2xNaClxCdCl2x3H2O and 3xNaClx4CdCl2x14H2O complexes. Changes of isobar potential at formation of the above compounds from the system components are calculated, based on the data on phase equilibriums

  20. High purity H-2/H2O/Ni/SZ electrodes at 500 degrees C

    Høgh, Jens Valdemar Thorvald; Hansen, Karin Vels; Norrman, Kion;

    2013-01-01

    The performance of SOFC (solid oxide fuel cell) anodes is influenced negatively by impurities. In the present study segregation of impurities is minimized by using high purity materials at relatively low temperatures to prevent fast segregation. Ni point electrodes on polished single crystals...... of stabilized zirconia (SZ) with 10,13 and 18 mol% yttria and one with 6 mol% scandia plus 4 mol% yttria were studied at open circuit voltage at 400-500 degrees C in mixtures of H-2/H2O over 46 days. The polarization resistances (R-p) for all samples increased significantly during the first 10-20 days at 500...

  1. Photon polarization in the 4He(γ,rvec d)2H reaction

    We derive double polarization observables for the photodisintegration of 4He with an incident polarized photon beam. In particular we study the effect of the ground state α-particle D wave on these observables in a simple nuclear model. We find that in general the double polarization observables offer no clear advantage to the corresponding variables studied in the single polarization 4He(γ,rvec d)2H reaction. However, the photon asymmetry Σ appears as a promising observable for the study of ground state effects

  2. Methyl N-{4-[(4-methoxyphenoxymethyl]-2-oxo-2H-chromen-7-yl}carbamate

    K. Mahesh Kumar

    2012-06-01

    Full Text Available In the title compound, C19H17NO6, the dihedral angle between the 2H-chromene ring system and benzene ring is 5.34 (6°. A short intramolecular C—H...O contact occurs. In the crystal, molecules are linked by N—H...O hydrogen bonds, generating C(8 chains propagating in [010]. The chains are linked by C—H...O interactions and the packing also exhibits π–π stacking interactions between benzene and pyran rings, with a centroid–centroid distance of 3.676 (9 Å.

  3. [2H26]-1-epi-Cubenol, a completely deuterated natural product from Streptomyces griseus

    Christian A. Citron

    2013-12-01

    Full Text Available During growth on fully deuterated medium the volatile terpene [2H26]-1-epi-cubenol was released by the actinomycete Streptomyces griseus. This compound represents the first completely deuterated terpene obtained by fermentation. Despite a few previous reports in the literature the operability of this approach to fully deuterated compounds is still surprising, because the strong kinetic isotope effect of deuterium is known to slow down all metabolic processes in living organisms. Potential applications of completely labelled compounds from natural sources in structure elucidation, biosynthetic or pharmacokinetic investigations are discussed.

  4. Crystal structure of 2-oxo-N′-phenyl-2H-chromene-3-carbohydrazide

    Joel T. Mague

    2015-12-01

    Full Text Available In the title compound, C16H12N2O3, the 2H-chromene moiety is essentially planar, with an r.m.s. deviation of the nine constituent atoms from the mean plane of 0.0093 Å, and makes a dihedral angle of 76.84 (3° with the pendant phenyl ring. An intramolecular N—H...O hydrogen bond helps to determine the conformation of the side chain. In the crystal, N—H...O and N—H...N hydrogen bonds link the molecules, forming [100] chains.

  5. Underestimation of glucose turnover measured with [6-3H]- and [6,6-2H]- but not [6-14C]glucose during hyperinsulinemia in humans

    Recent studies indicate that hydrogen-labeled glucose tracers underestimate glucose turnover in humans under conditions of high flux. The cause of this underestimation is unknown. To determine whether the error is time-, pool-, model-, or insulin-dependent, glucose turnover was measured simultaneously with [6-3H]-, [6,6-2H2]-, and [6-14C]glucose during a 7-h infusion of either insulin (1 mU.kg-1.min-1) or saline. During the insulin infusion, steady-state glucose turnover measured with both [6-3H]glucose (8.0 +/- 0.5 mg.kg-1.min-1) and [6,6-2H2]glucose (7.6 +/- 0.5 mg.kg-1.min-1) was lower (P less than .01) than either the glucose infusion rate required to maintain euglycemia (9.8 +/- 0.7 mg.kg-1.min-1) or glucose turnover determined with [6-14C]glucose and corrected for Cori cycle activity (9.8 +/- 0.7 mg.kg-1.min-1). Consequently negative glucose production rates (P less than .01) were obtained with either [6-3H]- or [6,6-2H2]- but not [6-14C]glucose. The difference between turnover estimated with [6-3H]glucose and actual glucose disposal (or 14C glucose flux) did not decrease with time and was not dependent on duration of isotope infusion. During saline infusion, estimates of glucose turnover were similar regardless of the glucose tracer used. High-performance liquid chromatography of the radioactive glucose tracer and plasma revealed the presence of a tritiated nonglucose contaminant. Although the contaminant represented only 1.5% of the radioactivity in the [6-3H]glucose infusate, its clearance was 10-fold less (P less than .001) than that of [6-3H]glucose. This resulted in accumulation in plasma, with the contaminant accounting for 16.6 +/- 2.09 and 10.8 +/- 0.9% of what customarily is assumed to be plasma glucose radioactivity during the insulin or saline infusion, respectively (P less than .01)

  6. Plasma properties

    This paper discusses the following topics: MHD plasma activity: equilibrium, stability and transport; statistical analysis; transport studies; edge physics studies; wave propagation analysis; basic plasma physics and fluid dynamics; space plasma; and numerical methods

  7. Plasma accelerators

    Recently attention has focused on charged particle acceleration in a plasma by a fast, large amplitude, longitudinal electron plasma wave. The plasma beat wave and plasma wakefield accelerators are two efficient ways of producing ultra-high accelerating gradients. Starting with the plasma beat wave accelerator (PBWA) and laser wakefield accelerator (LWFA) schemes and the plasma wakefield accelerator (PWFA) steady progress has been made in theory, simulations and experiments. Computations are presented for the study of LWFA. (author)

  8. EVIDENCE OF DIFFERENTIAL PH REGULATION OF THE ARABIDOPSIS VACUOLAR CA2+/H+ ANTIPORTERS CAX1 AND CAX2

    The Arabidopsis Ca(2+)/H(+) antiporters cation exchanger (CAX) 1 and 2 utilise an electrochemical gradient to transport Ca(2+) into the vacuole to help mediate Ca(2+) homeostasis. Previous whole plant studies indicate that activity of Ca(2+)/H(+) antiporters is regulated by pH. However, the pH regul...

  9. 2H-SiC Dendritic Nanocrystals In Situ Formation from Amorphous Silicon Carbide under Electron Beam Irradiation

    2006-01-01

    Under electron beam irradiation, the in-situ formation of 2H-SiC dentritic nanocrystals from amorphous silicon carbide at room temperature was observed. The homogenous transition mainly occurs at the thin edge and on the surface of specimen where the energy obtained from electron beam irradiation is high enough to cause the amorphous crystallizing into 2H-SiC.

  10. Rapid solid-state NMR of deuterated proteins by interleaved cross-polarization from 1H and 2H nuclei

    Bjerring, Morten; Paaske, Berit; Oschkinat, Hartmut; Akbey, Ümit; Nielsen, Niels Chr.

    2012-01-01

    We present a novel sampling strategy, interleaving acquisition of multiple NMR spectra by exploiting initial polarization subsequently from 1H and 2H spins, taking advantage of their different T1 relaxation times. Different 1H- and 2H-polarization based spectra are in this way simultaneously recorded improving either information content or sensitivity by adding spectra. The so-called Relaxation-optimized Acquisition of Proton Interleaved with Deuterium (RAPID) 1H → 13C/ 2H → 13C CP/MAS multiple-acquisition method is demonstrated by 1D and 2D experiments using a uniformly 2H, 15N, 13C-labeled α-spectrin SH3 domain sample with all or 30% back-exchanged labile 2H to 1H. It is demonstrated how 1D 13C CP/MAS or 2D 13C- 13C correlation spectra initialized with polarization from either 1H or 2H may be recorded simultaneously with flexibility to be added or used individually for spectral editing. It is also shown how 2D 13C- 13C correlation spectra may be recorded interleaved with 2H- 13C correlation spectra to obtain 13C- 13C correlations along with information about dynamics from 2H sideband patterns.

  11. Plasma harmonics

    Ganeev, Rashid A

    2014-01-01

    Preface; Why plasma harmonics? A very brief introduction Early stage of plasma harmonic studies - hopes and frustrations New developments in plasma harmonics studies: first successes Improvements of plasma harmonics; Theoretical basics of plasma harmonics; Basics of HHG Harmonic generation in fullerenes using few-cycle pulsesVarious approaches for description of observed peculiarities of resonant enhancement of a single harmonic in laser plasmaTwo-colour pump resonance-induced enhancement of odd and even harmonics from a tin plasmaCalculations of single harmonic generation from Mn plasma;Low-o

  12. Bound and continuum states of molecular anions C2H- and C3N-

    Harrison, Stephen; Tennyson, Jonathan

    2011-02-01

    Recently a number of molecular anions, closed-shell linear carbon chains of the form CnH- and CnN-, have been detected in space. The molecules C2H- and C3N- are investigated by using the R-matrix method to consider electron scattering from the corresponding neutral targets. Initial target calculations are conducted and refined in order to produce target state characteristics similar to the experimental data. A number of different scattering models are tested including static exchange and close-coupling models, and the use of Hartree-Fock or natural orbitals in the close-coupling calculations. The calculations concentrate on bound and resonances states for the anions as well as eigenphase sums, elastic cross-sections and electronic excitation cross-sections for electron collisions with the neutral. It is found that electronic resonances are all too high in energy to be important for anion formation in the interstellar medium. However, C3N-, unlike C2H-, supports a number of very weakly bound excited states, which may well provide the route to electron attachment for this system.

  13. Redetermination of [EuCl2(H2O6]Cl

    Frank Tambornino

    2014-06-01

    Full Text Available The crystal structure of the title compound, hexaaquadichloridoeuropium(III chloride, was redetermined with modern crystallographic methods. In comparison with the previous study [Lepert et al. (1983. Aust. J. Chem. 36, 477–482], it could be shown that the atomic coordinates of some O atoms had been confused and now were corrected. Moreover, it was possible to freely refine the positions of the H atoms and thus to improve the accurracy of the crystal structure. [EuCl2(H2O6]Cl crystallizes with the GdCl3·6H2O structure-type, exhibiting discrete [EuCl2(H2O6]+ cations as the main building blocks. The main blocks are linked with isolated chloride anions via O—H...Cl hydrogen bonds into a three-dimensional framework. The Eu3+ cation is located on a twofold rotation axis and is coordinated in the form of a Cl2O6 square antiprism. One chloride anion coordinates directly to Eu3+, whereas the other chloride anion, situated on a twofold rotation axis, is hydrogen bonded to six octahedrally arranged water molecules.

  14. Volumetric Properties and Fluid Phase Equilibria of CO2 + H2O

    Capobianco, Ryan [Virginia Polytechnic Institute and State University; Gruszkiewicz, Miroslaw {Mirek} S [ORNL; Wesolowski, David J [ORNL; Cole, David R [ORNL; Bodnar, Robert [Virginia Polytechnic Institute and State University

    2013-01-01

    The need for accurate modeling of fluid-mineral processes over wide ranges of temperature, pressure and composition highlighted considerable uncertainties of available property data and equations of state, even for the CO2 + H2O binary system. In particular, the solubility, activity, and ionic dissociation equilibrium data for the CO2-rich phase, which are essential for understanding dissolution/precipitation, fluid-matrix reactions, and solute transport, are uncertain or missing. In this paper we report the results of a new experimental study of volumetric and phase equilibrium properties of CO2 + H2O, to be followed by measurements for bulk and confined multicomponent fluid mixtures. Mixture densities were measured by vibrating tube densimetry (VTD) over the entire composition range at T = 200 and 250 C and P = 20, 40, 60, and 80 MPa. Initial analysis of the mutual solubilities, determined from volumetric data, shows good agreement with earlier results for the aqueous phase, but finds that the data of Takenouchi and Kennedy (1964) significantly overestimated the solubility of water in supercritical CO2 (by a factor of more than two at 200 C). Resolving this well-known discrepancy will have a direct impact on the accuracy of predictive modeling of CO2 injection in geothermal reservoirs and geological carbon sequestration through improved equations of state, needed for calibration of predictive molecular-scale models and large-scale reactive transport simulations.

  15. Affordable uniform isotope labeling with 2H, 13C and 15N in insect cells

    For a wide range of proteins of high interest, the major obstacle for NMR studies is the lack of an affordable eukaryotic expression system for isotope labeling. Here, a simple and affordable protocol is presented to produce uniform labeled proteins in the most prevalent eukaryotic expression system for structural biology, namely Spodoptera frugiperda insect cells. Incorporation levels of 80 % can be achieved for 15N and 13C with yields comparable to expression in full media. For 2H,15N and 2H,13C,15N labeling, incorporation is only slightly lower with 75 and 73 %, respectively, and yields are typically twofold reduced. The media were optimized for isotope incorporation, reproducibility, simplicity and cost. High isotope incorporation levels for all labeling patterns are achieved by using labeled algal amino acid extracts and exploiting well-known biochemical pathways. The final formulation consists of just five commercially available components, at costs 12-fold lower than labeling media from vendors. The approach was applied to several cytosolic and secreted target proteins

  16. Influence of high absorbed irradiation doses on conversion of CO2-H2S mixtures

    It was investigated the CO2-H2S mixture radiolysis at large absorbed irradiation doses. The observed high yield of final products in this system (Gpr.≥10.0) gives the possibility to consider the radiolytic hydrogen sulphide decomposition as one of the variants of purification of hydrogen sulphide containing residues of natural gas with a simultaneous production of sulphur and synthesis-gas (CO2). It has been show that at dose MGy∼16 % of initial product convert into synthesis-gas and sulfur. The mechanism of radiolytic conversion is discussed and the observed yield of hydrogen made G0(H2)=11.0±0.8 that considerably excesses G0(H2) at radiolysis of pure H2S(G0(H2)=7.5±0.5). Accumulation of carbon monoxide is described with 5 % accuracy with parabola of the second order: [CO] (-0.00082+0.359D-0.0013D2)·1019 mol/cm3 the initial yield of CO production for the given mixture is equal 3.59 which is G0(CO) = 4.5 in recalculation upon pure carbon dioxide. It has been established that the radiolytic reprocessing of acidic components of natural gas (CO2, H2S) gives the possibility to product sulphur and synthesis gas with yield to 30 vol.% (D=10 MGy), and the opportunity of simultaneous decision of ecological problems

  17. Emission spectroscopic study of the system F2-H2 in the shock tube

    In a shock tube Ar-F2-H2-mixtures, containing 0.2% F2 and 0.2% H2, were heated up to temperatures of approx. 830 respectively 940 K. The pressures amounted to 4.0 respectively 3.6 bar. The following reaction was observed via the radiation emission of the vibrational excited HF-molecules. The spectral range from 660 to 960 nm was investigated. From these measurements it was possible to determine the population numbers of discrete vibrational levels (v = 3,...,9) of the HF-molecule. Chemical kinetic calculations were carried out in order to evaluate from these measurements informations on rate coefficients of certain elementary reactions. By adapting the calculations to the measurements it was found among others, that VVT-processes between HF and HF do occur much faster at higher vibrational quantum numbers than originally supposed. Furthermore, statements could be made on VT-processes between HF and Ar as well as on the pumping reaction H + F2 → HF + F. (orig.)

  18. Emission-spectroscopic investigation of the F2-H2-system in a shock tube

    In a shock tube Ar-F2-H2-mixtures, containing 0.2% F2 and 0.2% H2, were heated up to temperatures of appr. 830 resp. 940 K. The pressures amounted to 4.0 resp. 3.6 bar. The reaction between H2 and F2 was observed via the radiation emission of the vibrational excited HF-molecules. The spectral range from 660 to 960 nm was investigated. From these measurements it was possible to determine population numbers of discrete vibrational levels (v = 3,...9) of the HF-molecule. Chemical kinetic calculations were carried out in order to evaluate from these measurements informations on rate coefficients of certain elementary reactions. By adapting the calculations to the measurements it was found among others, that VVT-relaxation processes between HF and HF occur much faster at higher vibrational quantum numbers than it was supposed up to now. Furthermore, some preliminary results were obtained on VT-relaxation processes between HF and Ar as well as on the pumping reaction H + F2 → HF + F. (orig.)

  19. THE COSMIC DECLINE IN THE H2/H I RATIO IN GALAXIES

    We use a pressure-based model for splitting cold hydrogen into its atomic (H I) and molecular (H2) components to tackle the co-evolution of H I, H2, and star formation rates (SFR) in ∼3 x 107 simulated galaxies in the Millennium simulation. The main prediction is that galaxies contained similar amounts of H I at redshift z ∼ 1-5 than today, but substantially more H2, in quantitative agreement with the strong molecular line emission already detected in a few high-redshift galaxies and approximately consistent with inferences from studies of the damped Lyman-α absorbers seen in the spectra of quasars. The cosmic H2/H I ratio is predicted to evolve monotonically as ΩH2/ΩHI∝(1+z)1.6. This decline of the H2/H I ratio as a function of cosmic time is driven by the growth of galactic disks and the progressive reduction of the mean cold gas pressure. Finally, a comparison between the evolutions of H I, H2, and SFRs reveals two distinct cosmic epochs of star formation: an early epoch (z ∼> 3), driven by the evolution of ΩHI+H2(z), and a late epoch (z ∼H2(z)/ΩHI(z).

  20. Solar photocatalytic degradation of isoproturon over TiO2/H-MOR composite systems

    The photocatalytic degradation and mineralization of isoproturon herbicide was investigated in aqueous solution containing TiO2 over H-mordenite (H-MOR) photocatalysts under solar light. The catalysts are characterized by X-ray diffraction (XRD), UV-Vis diffused reflectance spectra (UV-Vis DRS), Fourier transform-infra red spectra (FT-IR) and scanning electron microscopy (SEM) techniques. The effect of TiO2, H-MOR support and different wt% of TiO2 over the support on the photocatalytic degradation and influence of parameters such as TiO2 loading, catalyst amount, pH and initial concentration of isoproturon on degradation are evaluated. 15 wt% TiO2/H-MOR composite is found to be optimum. The degradation reaction follows pseudo-first order kinetics and is discussed in terms of Langmuir-Hinshelwood (L-H) kinetic model. The extent of isoproturon mineralization studied with chemical oxygen demand (COD) and total organic carbon (TOC) measurements and ∼80% mineralization occurred in 5 h. A plausible mechanism is proposed based on the intermediates identified by liquid chromatography-mass spectroscopy (LC-MS)

  1. Trojan Horse particle invariance for 2H(d,p3H reaction: a detailed study

    Pizzone R.G.

    2014-03-01

    Full Text Available In the last decades the Trojan Horse method has played a crucial role for the measurement of several charged particle induced reactions cross sections of astrophysical interest. To better understand its cornerstones and its applications to physical cases many tests were performed to verify all its properties and the possible future perspectives. The Trojan Horse nucleus invariance for the binary d(d,pt reaction was therefore tested using the quasi free 2H(6Li, pt4He and 2H(3He,ptH reactions after 6Li and 3He break-up, respectively. The astrophysical S(E-factor for the d(d,pt binary process was then extracted in the framework of the Plane Wave Approximation applied to the two different break-up schemes. The obtained results are compared with direct data as well as with previous indirect investigations. The very good agreement confirms the applicability of the plane wave approximation and suggests the independence of binary indirect cross section on the chosen Trojan Horse nucleus also for the present case.

  2. Trojan Horse particle invariance for 2H(d,p)3H reaction: a detailed study

    Pizzone, R. G.; Spitaleri, C.; Bertulani, C. A.; Mukhamedzhanov, A. M.; Blokhintsev, L.; La Cognata, M.; Lamia, L.; Rinollo, A.; Spartá, R.; Tumino, A.

    2014-03-01

    In the last decades the Trojan Horse method has played a crucial role for the measurement of several charged particle induced reactions cross sections of astrophysical interest. To better understand its cornerstones and its applications to physical cases many tests were performed to verify all its properties and the possible future perspectives. The Trojan Horse nucleus invariance for the binary d(d,p)t reaction was therefore tested using the quasi free 2H(6Li, pt)4He and 2H(3He,pt)H reactions after 6Li and 3He break-up, respectively. The astrophysical S(E)-factor for the d(d,p)t binary process was then extracted in the framework of the Plane Wave Approximation applied to the two different break-up schemes. The obtained results are compared with direct data as well as with previous indirect investigations. The very good agreement confirms the applicability of the plane wave approximation and suggests the independence of binary indirect cross section on the chosen Trojan Horse nucleus also for the present case.

  3. Graphite Nanostructures Produce in the Acetilene, Argon-Acetylene and Argon-Hydrogen-Acetylene Plasmas

    Grigonis A.; Marcinauskas L.; Carnauskas M.; Kaliasas R.

    2012-01-01

    The amorphous carbon films were deposited on silicon-metal substrates by plasma jet chemical vapor deposition (PJCVD) and plasma enchanted CVD (PECVD). PJCVD carbon coatings have been prepared at atmospheric pressure in Ar/ C2H2 and Ar/H2/C2H2 mixtures. The films prepared in Ar/C2H2 plasma are at-tributed to graphite-like carbon films. Addition of the hydrogen decreases growth rate and the surface roughness of the coatings, but coatings have low fraction of oxygen (~5 at.%) The formation of t...

  4. Effect of Sterol Structure on Chain Ordering of an Unsaturated Phospholipid: A 2H-NMR Study of POPC/Sterol Membranes

    Shaghaghi, Mehran; Thewalt, Jenifer; Zuckermann, Martin

    2012-10-01

    The physical properties of biological membranes are considerably altered by the presence of sterols. In particular, sterols help to maintain the integrity of the cell by adjusting the fluidity of the plasma membrane. Cholesterol is in addition an important component of lipid rafts which are hypothesized to compartmentalize the cell membrane surface thereby making it possible for certain proteins to function. Using 2H-NMR spectroscopy, we studied the effect of a series of different sterols on the chain ordering of POPC, an unsaturated phospholipid present in eukaryotic cell membranes. We were able to assigned specific roles to the structural differences between the sterols by comparing the manner in which they affect the average lipid chain conformation of POPC.

  5. Pulsed RF Plasma Source for Materials Processing

    Nasiruddin, Abutaher Mohammad

    A pulsed rf plasma source was evaluated for materials processing. A pulsed rf discharge of carbon tetrafluoride (CF_4), sulfur hexafluoride (SF _6), oxygen (O_2), or acetylene (C_2H_2 ) created the plasmas. The frequency and duration of the rf discharge were about 290 kHz and 30 musec, respectively. The repetition rate was 1 discharge per minute. Plasma diagnostics included Langmuir probes, a photodiode dectector, an optical multichannel analyzer (OMA), and a microwave interferometer. Langmuir probe measurements showed that at a position 67 cm away from the rf coil, CF_4 plasma arrived in separate packets. Plasma densities and electron temperatures at this position were in the range 4 times 10^{11} cm ^{-3} to 1.8 times 10^{13} cm ^{-3} and 2 eV to 8.3 eV, respectively. The OMA measurements identified neutral atomic fluorine in the CF_4 plasma and neutral atomic oxygen in the O_2 plasma. A plasma slab model of the microwave interferometer was applied to predict the interferometer response. The measured response was found to be almost identical to the predicted response. The influence of different reactor parameters on plasma parameters was studied. Metal barriers of different geometry were used to control the ratio of charged particles to atomic neutrals in the plasma chamber. Four plasma structures were identified: precursor plasma, shock induced plasma, driver plasma, and delayed glow plasma. Pulsed CF _4 and SF_6 plasmas were used to etch silicon dioxide (SiO_2 ) grown on silicon wafers. The SF_6 plasma etched SiO_2 at a rate of about 0.71 A per discharge and the CF_4 plasma deposited a non-uniform film (possibly polymer) instead of etching. The C_2H _2 plasma deposited plasma polymerized acetylene on a KBr pellet with a deposition rate of 127 A per discharge. An FT-IR spectrum of the deposited film showed that carbon -to-carbon double bonds as well as carbon-to-hydrogen bonds were present. This device can be used in plasma assisted deposition and/or synthesis

  6. Sterilization Effect of Wet Oxygen Plasma in the Bubbling Method.

    Tamazawa, Kaoru; Shintani, Hideharu; Tamazawa, Yoshinori; Shimauchi, Hidetoshi

    2015-01-01

    A new low-temperature sterilization method to replace the ethylene oxide gas sterilization is needed. Strong bactericidal effects of OH and O2H radicals are well known. The purpose of this study was to evaluate the sterilization effect of wet oxygen ("O2+H2O") plasma in the bubbling method, confirming the effect of humidity. Sterility assurance was confirmed by using a biological indicator (Geobacillus stearothermophilus ATCC7953, Namsa, USA). One hundred and eight samples (10(5) spores/carrier) were divided into three groups of 36 in each for treatment with a different type of gas (O2, O2+H2O, Air+H2O). Plasma processing was conducted using a plasma ashing apparatus (13.56 MHz, PACK-3(®), Y. A. C., Japan) under various gas pressures (13, 25, 50 Pa) and gas flows (50, 100, 200 sccm). Fixed plasma treatment parameters were power at 150 W, temperature of 60 ℃, treatment time of 10 min. The samples after treatment were incubated in trypticase soy broth at 58 ℃ for 72 h. The negative culture rate in the "O2+H2O" group was significantly (Mantel-Haenszel procedure, psterilization effect of the "O2+H2O" group depends on the bubbling method which is the method of introducing vapor into the chamber. The bubbling method seems able to generate OH and O2H radicals in a stable way. PMID:26699857

  7. Modeling Ice Giant Interiors Using Constraints on the H2-H2O Critical Curve

    Bailey, E.; Stevenson, D. J.

    2015-12-01

    We present a range of models of Uranus and Neptune, taking into account recent experimental data (Bali, 2013) implying the location of the critical curve of the H2-H2O system at pressures up to 2.6 GPa. The models presented satisfy the observed total mass of each planet and the radius at the observed 1-bar pressure level. We assume the existence of three regions at different depths: an outer adiabatic envelope composed predominately of H2 and He, with a helium mass fraction 0.26, a water-rich layer including varied amounts of rock and hydrogen, and a chemically homogeneous rock core. Using measured rotation rates of Uranus and Neptune, and a density profile obtained for each model using constituent equations of state and the assumption of hydrostatic equilibrium, we calculate the gravitational harmonics J2 and J4 for comparison with observed values as an additional constraint. The H2-H2O critical curve provides information about the nature of the boundary between the outer, hydrogen-rich envelope and underlying water-rich layer. The extrapolated critical curve for hydrogen-water mixtures crosses the adiabat of the outer atmospheric shell in these models at two depths, implying a shallow outer region of limited miscibility, an intermediate region between ~90 and 98 percent of the total planet radius within which hydrogen and water can mix in all proportions, and another, deeper region of limited miscibility at less than ~90 percent of the total planet radius. The pressure and temperature of the gaseous adiabatic shell at the depth of the shallowest extent of the water-rich layer determines whether a gradual compositional transition or an ocean surface boundary may exist at depth in these planets. To satisfy the observed J2, the outer extent of the water-rich layer in these models must be located between approximately 80 and 85 percent of the total planet radius, within the deep region of limited H2-H2O miscibility, implying an ocean surface is possible within the

  8. SNF2H interacts with XRCC1 and is involved in repair of H2O2-induced DNA damage.

    Kubota, Yoshiko; Shimizu, Shinji; Yasuhira, Shinji; Horiuchi, Saburo

    2016-07-01

    The protein XRCC1 has no inherent enzymatic activity, and is believed to function in base excision repair as a dedicated scaffold component that coordinates other DNA repair factors. Repair foci clearly represent the recruitment and accumulation of DNA repair factors at sites of damage; however, uncertainties remain regarding their organization in the context of nuclear architecture and their biological significance. Here we identified the chromatin remodeling factor SNF2H/SMARCA5 as a novel binding partner of XRCC1, with their interaction dependent on the casein kinase 2-mediated constitutive phosphorylation of XRCC1. The proficiency of repairing H2O2-induced damage was strongly impaired by SNF2H knock-down, and similar impairment was observed with knock-down of both XRCC1 and SNF2H simultaneously, suggesting their role in a common repair pathway. Most SNF2H exists in the nuclear matrix fraction, forming salt extraction-resistant foci-like structures in unchallenged nuclei. Remarkably, damage-induced formation of both PAR and XRCC1 foci depended on SNF2H, and the PAR and XRCC1 foci co-localized with the SNF2H foci. We propose a model in which a base excision repair complex containing damaged chromatin is recruited to specific locations in the nuclear matrix for repair, with this recruitment mediated by XRCC1-SNF2H interaction. PMID:27268481

  9. Satellite observations of ethylene (C2H4) from the Aura Tropospheric Emission Spectrometer: A scoping study

    Dolan, Wayana; Payne, Vivienne H.; Kualwik, Susan S.; Bowman, Kevin W.

    2016-09-01

    We present a study focusing on detection and initial quantitative estimates of ethylene (C2H4) in observations from the Tropospheric Emission Spectrometer (TES), a Fourier transform spectrometer aboard the Aura satellite that measures thermal infrared radiances with high spectral resolution (0.1 cm-1). We analyze observations taken in support of the 2008 Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) mission and demonstrate the feasibility of future development of C2H4 into a TES standard product. In the Northern Hemisphere, C2H4 is commonly associated with boreal fire plumes, motor vehicle exhaust and petrochemical emissions. It has a short lifetime (∼14-32 h) in the troposphere due to its reaction with OH and O3. Chemical destruction of C2H4 in the atmosphere leads to the production of ozone and other species such as carbon monoxide (CO) and formaldehyde. Results indicate a correlation between C2H4 and CO in boreal fire plumes. Quantitative C2H4 estimates are sensitive to assumptions about the plume height and width. We find that C2H4 greater than 2-3 ppbv can be detected in a single TES observation (for a fire plume at 3 km altitude and 1.5 km width). Spatial averaging will be needed for surface-peaking profiles where TES sensitivity is lower.

  10. Tris[2-(2H-indazol-2-ylethyl]amine

    Saúl Ovalle

    2012-06-01

    Full Text Available The title tertiary amine, C27H27N7, a potential tripodal ligand for coordination chemistry, crystallizes with the central N atom located on a threefold axis of a trigonal cell. The gauche conformation of the N(amime—CH2—CH2—N(indazole chain [torsion angle = −64.2 (2°] places the pendant 2H-indazole heterocycles surrounding the symmetry axis, affording a claw-like shaped molecule. Two symmetry-related indazole planes in the molecule make an acute angle of 60.39 (4°. The lone pair of the tertiary N atom is located inside the cavity, and should thus be inactive (as a ligand. In the crystal, neither significant π–π nor C—H...π interactions between molecules are found.