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Sample records for psia hydrogen partial

  1. Prevalence of partially hydrogenated oils in US packaged foods, 2012.

    Science.gov (United States)

    Clapp, Jenifer; Curtis, Christine J; Middleton, Ann E; Goldstein, Gail P

    2014-08-28

    Although there is evidence that consumption of trans fat has declined in the United States, limited documentation exists on current levels of industrial trans fat in foods. We estimated the prevalence of partially hydrogenated oils in 4,340 top-selling US packaged foods. Nine percent of products in the sample contained partially hydrogenated oils; 84% of these products listed "0 grams" of trans fat per serving, potentially leading consumers to underestimate their trans fat consumption. Government efforts to eliminate partially hydrogenated oils from packaged foods will substantially reduce exposure to this known cardiovascular disease risk factor.

  2. Catalytic partial oxidation of methanol and ethanol for hydrogen generation.

    Science.gov (United States)

    Hohn, Keith L; Lin, Yu-Chuan

    2009-01-01

    Hydrogen-powered fuel cell vehicles feature high energy efficiency and minor environmental impact. Liquid fuels are ideal hydrogen carriers, which can catalytically be converted into syngas or hydrogen to power vehicles. Among the potential liquid fuels, alcohols have several advantages. The hydrogen/carbon ratio is higher than that of other liquid hydrocarbons or oxygenates, especially in the case of methanol. In addition, alcohols can be derived from renewable biomass resources. Catalytic partial oxidation of methanol or ethanol offers immense potential for onboard hydrogen generation due to its rapid reaction rate and exothermic nature. These benefits stimulate a burgeoning research community in catalyst design, reaction engineering, and mechanistic investigation. The purpose of this Minireview is to provide insight into syngas and hydrogen production from methanol and ethanol partial oxidation, particularly highlighting catalytic chemistry.

  3. The Effect of Hydrogen Partial Pressure on Methylcyclopentane Ring Opening.

    NARCIS (Netherlands)

    Koningsberger, D.C.; Vaarkamp, M.; Dijkstra, P.; Grondelle, J. van; Miller, J.T.; Modica, F.S.; Sante, R.A. van

    1995-01-01

    The ring opening of methylcyclopentane (MCP) over well-characterized Pt/SiO{2}(EUROPT-1), Pt/@c-Al{2}O{3}, and Pt/K-LTL catalysts was studied as a function of hydrogen partial pressure and reduction temperature. The MCP ring opening selectivity did not change in the range of H{2}:MCP ratios studied

  4. Dynamic Conductivity and Partial Ionization in Warm, Dense Hydrogen

    Science.gov (United States)

    Zaghoo, M.; Silvera, I. F.

    2017-10-01

    A theoretical description for optical conduction experiments in dense fluid hydrogen is presented. Different quantum statistical approaches are used to describe the mechanism of electron transport in hydrogen's high-temperature dense phase. We show that at the onset of the metallic transition, optical conduction could be described by a strong rise in the atomic polarizability, resulting from increased ionization; whereas in the highly degenerate limit, the Ziman weak-scattering model better describes the observed saturation of reflectance. In the highly degenerate region, the inclusion of partial ionization effects provides excellent agreement with experimental results. Hydrogen's fluid metallic state is revealed to be a partially ionized free-electron plasma. These results provide a crucial benchmark for ab initio calculations as well as an important guide for future experiments. Research supported by DOE Stockpile Stewardship Academic Alliance Program, Grant DE-FG52-10NA29656, and NASA Earth and Space Science Fellowship Program, Award NNX14AP17H.

  5. Potential hydrogen and oxygen partial pressures in legacy plutonium oxide packages at Oak Ridge

    Energy Technology Data Exchange (ETDEWEB)

    Veirs, Douglas K. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-07-07

    An approach to estimate the maximum hydrogen and oxygen partial pressures within sealed containers is described and applied to a set of packages containing high-purity plutonium dioxide. The approach uses experimentally determined maximum hydrogen and oxygen partial pressures and scales the experimentally determined pressures to the relevant packaged material properties. The important material properties are the specific wattage and specific surface area (SSA). Important results from the experimental determination of maximum partial pressures are (1) the ratio of hydrogen to oxygen is stoichiometric, and (2) the maximum pressures increase with increasing initial rates of production. The material properties that influence the rates are the material specific wattage and the SSA. The unusual properties of these materials, high specific wattage and high SSA, result in higher predicted maximum pressures than typical plutonium dioxide in storage. The pressures are well within the deflagration range for mixtures of hydrogen and oxygen.

  6. Sensor for measuring hydrogen partial pressure in parabolic trough power plant expansion tanks

    Science.gov (United States)

    Glatzmaier, Greg C.; Cooney, Daniel A.

    2017-06-01

    The National Renewable Energy Laboratory and Acciona Energy North America are working together to design and implement a process system that provides a permanent solution to the issue of hydrogen buildup at parabolic trough power plants. We are pursuing a method that selectively removes hydrogen from the expansion tanks that serve as reservoirs for the heat transfer fluid (HTF) that circulates in the collector field and power block components. Our modeling shows that removing hydrogen from the expansion tanks at a design rate reduces and maintains dissolved hydrogen in the circulating HTF to a selected target level. Our collaborative work consists of several tasks that are needed to advance this process concept to a development stage, where it is ready for implementation at a commercial power plant. Our main effort is to design and evaluate likely process-unit operations that remove hydrogen from the expansion tanks at a specified rate. Additionally, we designed and demonstrated a method and instrumentation to measure hydrogen partial pressure and concentration in the expansion-tank headspace gas. We measured hydrogen partial pressure in the headspace gas mixture using a palladium-alloy membrane, which is permeable exclusively to hydrogen. The membrane establishes a pure hydrogen gas phase that is in equilibrium with the hydrogen in the gas mixture. We designed and fabricated instrumentation, and demonstrated its effectiveness in measuring hydrogen partial pressures over a range of three orders of magnitude. Our goal is to install this instrument at the Nevada Solar One power plant and to demonstrate its effectiveness in measuring hydrogen levels in the expansion tanks under normal plant operating conditions.

  7. Sensor for Measuring Hydrogen Partial Pressure in Parabolic Trough Power Plant Expansion Tanks

    Energy Technology Data Exchange (ETDEWEB)

    Glatzmaier, Greg C.; Cooney, Daniel A.

    2017-06-27

    The National Renewable Energy Laboratory and Acciona Energy North America are working together to design and implement a process system that provides a permanent solution to the issue of hydrogen buildup at parabolic trough power plants. We are pursuing a method that selectively removes hydrogen from the expansion tanks that serve as reservoirs for the heat transfer fluid (HTF) that circulates in the collector field and power block components. Our modeling shows that removing hydrogen from the expansion tanks at a design rate reduces and maintains dissolved hydrogen in the circulating HTF to a selected target level. Our collaborative work consists of several tasks that are needed to advance this process concept to a development stage, where it is ready for implementation at a commercial power plant. Our main effort is to design and evaluate likely process-unit operations that remove hydrogen from the expansion tanks at a specified rate. Additionally, we designed and demonstrated a method and instrumentation to measure hydrogen partial pressure and concentration in the expansion-tank headspace gas. We measured hydrogen partial pressure in the headspace gas mixture using a palladium-alloy membrane, which is permeable exclusively to hydrogen. The membrane establishes a pure hydrogen gas phase that is in equilibrium with the hydrogen in the gas mixture. We designed and fabricated instrumentation, and demonstrated its effectiveness in measuring hydrogen partial pressures over a range of three orders of magnitude. Our goal is to install this instrument at the Nevada Solar One power plant and to demonstrate its effectiveness in measuring hydrogen levels in the expansion tanks under normal plant operating conditions.

  8. Quantum statistical mechanics of dense partially ionized hydrogen.

    Science.gov (United States)

    Dewitt, H. E.; Rogers, F. J.

    1972-01-01

    The theory of dense hydrogenic plasmas beginning with the two component quantum grand partition function is reviewed. It is shown that ionization equilibrium and molecular dissociation equilibrium can be treated in the same manner with proper consideration of all two-body states. A quantum perturbation expansion is used to give an accurate calculation of the equation of state of the gas for any degree of dissociation and ionization. In this theory, the effective interaction between any two charges is the dynamic screened potential obtained from the plasma dielectric function. We make the static approximation; and we carry out detailed numerical calculations with the bound and scattering states of the Debye potential, using the Beth-Uhlenbeck form of the quantum second virial coefficient. We compare our results with calculations from the Saha equation.

  9. Pressure of a partially ionized hydrogen gas : numerical results from exact low temperature expansions

    OpenAIRE

    Alastuey, Angel; Ballenegger, Vincent

    2010-01-01

    8 pages; International audience; We consider a partially ionized hydrogen gas at low densities, where it reduces almost to an ideal mixture made with hydrogen atoms in their ground-state, ionized protons and ionized electrons. By performing systematic low-temperature expansions within the physical picture, in which the system is described as a quantum electron-proton plasma interacting via the Coulomb potential, exact formulae for the first five leading corrections to the ideal Saha equation ...

  10. Partial oxidation of n-hexadecane through decomposition of hydrogen peroxide in supercritical water

    KAUST Repository

    Alshammari, Y.M.

    2015-01-01

    © 2014 The Institution of Chemical Engineers. This work reports the experimental analysis of partial oxidation of n-hexadecane under supercritical water conditions. A novel reactor flow system was developed which allows for total decomposition of hydrogen peroxide in a separate reactor followed partial oxidation of n-hexadecane in a gasification reactor instead of having both reactions in one reactor. The kinetics of hydrothermal decomposition of hydrogen peroxide was studied in order to confirm its full conversion into water and oxygen under the desired partial oxidation conditions, and the kinetic data were found in a good agreement with previously reported literature. The gas yield and gasification efficiency were investigated under different operating parameters. Furthermore, the profile of C-C/C=C ratio was studied which showed the favourable conditions for maximising yields of n-alkanes via hydrogenation of their corresponding 1-alkenes. Enhanced hydrogenation of 1-alkenes was observed at higher O/C ratios and higher residence times, shown by the increase in the C-C/C=C ratio to more than unity, while increasing the temperature has shown much less effect on the C-C/C=C ratio at the current experimental conditions. In addition, GC-MS analysis of liquid samples revealed the formation of heavy oxygenated compounds which may suggest a new addition reaction to account for their formation under the current experimental conditions. Results show new promising routes for hydrogen production with in situ hydrogenation of heavy hydrocarbons in a supercritical water reactor.

  11. Hydrogen gas permeation through amorphous and partially crystallized Fe40Ni38Mo4B18

    Directory of Open Access Journals (Sweden)

    Rafaella Martins Ribeiro

    2012-10-01

    Full Text Available Samples of amorphous and partially crystallized Fe40Ni38Mo4B18 alloy were submitted to hydrogen gas permeation from 523 to 643 K. The hydrogen permeation curves exhibited a single sigmoidal shape, typical of tests where no hydride formation occurs. It was observed that the hydrogen diffusivity increases for the amorphous samples and partially crystallized alloy with the temperature increase. The hydrogen diffusion coefficient as a function of temperature was found to be D = 5.1 ± 0.5 × 10-12 exp (-11.0 ± 3.5/RT (m².s-1 for amorphous condition and D = 3.6 ± 0.5 × 10-11 exp (-19.8 ± 3.3/RT (m².s-1 for the partially crystallized condition. This suggests that the annihilation of defects in the amorphous structure and the crystalline phase precipitate contributes to the increase of the hydrogen diffusion.

  12. Microscopic and thermodynamic properties of dense semiclassical partially ionized hydrogen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Ramazanov, T S; Dzhumagulova, K N; Gabdullin, M T [IETP, Al-Farabi Kazakh National University, 96a, Tole Bi St, Almaty, 050012 (Kazakhstan)

    2006-04-28

    Microscopic and thermodynamic properties of dense semiclassical partially ionized hydrogen plasma were investigated on the basis of pseudopotential models. Radial distribution functions (RDF) of particles were obtained using a system of the Ornstein-Zernike integral equations. The corrections to internal energy and the equation of state were calculated using RDF.

  13. Separation of FFA from Partially Hydrogenated Soybean Oil Hydrolysate by Means of Membrane Processing

    DEFF Research Database (Denmark)

    Jala, Ram Chandra Reddy; Guo, Zheng; Xu, Xuebing

    2011-01-01

    Different types of commercial porous and non-porous polymeric membranes have been investigated for their capabilities to separate free fatty acids (FFA) from hydrolysate of partially hydrogenated soybean oil. A regenerated cellulose (RC, PLAC) membrane exhibited the most prominent difference...

  14. The role of hydrogen partial pressure on the annealing of copper substrates for graphene CVD synthesis

    Science.gov (United States)

    Ramos, Welyson T. S.; Cunha, Thiago H. R.; Barcelos, Ingrid D.; Miquita, Douglas R.; Ferrari, Gustavo A.; de Oliveira, Sergio; Seara, Luciana M.; Silva Neto, Eliel G.; Ferlauto, Andre S.; Lacerda, Rodrigo G.

    2016-04-01

    The influence of hydrogen utilized during the thermal treatment of copper substrates on the subsequent graphene growth is investigated. It is known that various parameters such as nature of the carbon precursor, temperature and pressure strongly affect the quality of the graphene grown by chemical vapor deposition. Another important parameter is the hydrogen partial pressure adjusted during the growth stage and in the pre-growth annealing of the substrate. In attempts to elucidate the role of hydrogen assisted thermal annealing on the copper substrate morphology and on the subsequent graphene growth, we subjected Cu foils to thermal annealing under H2 atmosphere at different pressures. The copper surface was characterized by scanning electronic microscopy (SEM) and atomic force microscopy whereas graphene films and grains were characterized by Raman spectroscopy and SEM. Our findings suggest that hydrogen not only affect the Cu surface but also diffuses into the substrate, being stored in the bulk material during the thermal treatment of the substrate. The release of hydrogen species in the subsequent stages of growth can result in damage to the graphene layer or induce the nucleation of additional layers depending on the growth and pre-growth conditions. Therefore, the use of hydrogen during the annealing of ‘low purity Cu foils’ should be carefully planned in order to obtain high quality graphene via LPCVD.

  15. Lithium and boron as interstitial palladium dopants for catalytic partial hydrogenation of acetylene.

    Science.gov (United States)

    Ellis, Ieuan T; Wolf, Elisabeth H; Jones, Glenn; Lo, Ben; Meng-Jung Li, Molly; York, Andrew P E; Edman Tsang, Shik Chi

    2017-01-03

    It is demonstrated that light elements, including lithium and boron atoms, can take residence in the octahedral (interstitial) site of a Pd lattice by modifying the electronic properties of the metal nanoparticles, and hence the adsorptive strength of a reactant. The blocking of the sub-surface sites to H in the modified materials results in significantly higher selectivity for the partial catalytic hydrogenation of acetylene to ethylene.

  16. Continuous-flow processes for the catalytic partial hydrogenation reaction of alkynes

    Directory of Open Access Journals (Sweden)

    Carmen Moreno-Marrodan

    2017-04-01

    Full Text Available The catalytic partial hydrogenation of substituted alkynes to alkenes is a process of high importance in the manufacture of several market chemicals. The present paper shortly reviews the heterogeneous catalytic systems engineered for this reaction under continuous flow and in the liquid phase. The main contributions appeared in the literature from 1997 up to August 2016 are discussed in terms of reactor design. A comparison with batch and industrial processes is provided whenever possible.

  17. Steam and partial oxidation reforming options for hydrogen production from fossil fuels for PEM fuel cells

    Directory of Open Access Journals (Sweden)

    Yousri M.A. Welaya

    2012-06-01

    Full Text Available Proton exchange membrane fuel cell (PEM generates electrical power from air and from hydrogen or hydrogen rich gas mixtures. Therefore, there is an increasing interest in converting current hydrocarbon based marine fuels such as natural gas, gasoline, and diesel into hydrogen rich gases acceptable to the PEM fuel cells on board ships. Using chemical flow sheeting software, the total system efficiency has been calculated. Natural gas appears to be the best fuel for hydrogen rich gas production due to its favorable composition of lower molecular weight compounds. This paper presents a study for a 250 kW net electrical power PEM fuel cell system utilizing a partial oxidation in one case study and steam reformers in the second. This study has shown that steam-reforming process is the most competitive fuel processing option in terms of fuel processing efficiency. Partial oxidation process has proved to posses the lowest fuel processing efficiency. Among the options studied, the highest fuel processing efficiency is achieved with natural gas steam reforming system.

  18. Selective hydrogenation in trickle-bed reactor. Experimental and modelling including partial wetting.

    OpenAIRE

    Dietz, Adrian; Julcour-Lebigue, Carine; Wilhelm, Anne-Marie; Delmas, Henri

    2003-01-01

    International audience; A steady state model of a trickle bed reactor is developed for the consecutive hydrogenation of 1,5,9-cyclododecatriene on a Pd/Al2O3 catalyst. Various experiments have shown that the selectivity of this reaction towards the product of interest is much lower in co-current down-flow (trickle-bed) than in up-flow. This is due to uneven liquid distribution and to partial wetting of the catalyst surface at low liquid flow rates. The non-isothermal heterogeneous model propo...

  19. Molecular hydrogen: a benchmark system for near threshold resonances in high partial waves

    Science.gov (United States)

    Shu, D.; Simbotin, I.; Côté, R.

    2017-10-01

    Benchmark reactions involving molecular hydrogen, such as H2 + D or H2 + Cl, provide the ideal platforms to investigate the effect of near threshold resonances (NTR) on scattering processes. Due to the small reduced mass of such systems, shape resonances in certain partial waves can provide features at scattering energies up to a few kelvin, achievable in current experiments. We explore the effects of NTRs on elastic and inelastic scattering for various partial waves ℓ (in the case of H2 + Cl for s-wave and H2 + D for p-wave scattering) and find that NTRs lead to a different energy scaling of the cross sections as compared to the well known Wigner threshold regime. We give a theoretical analysis based on Jost functions, and we explore the NTR effects for higher partial waves using a simple model that incorporates the key ingredients of coupled-channel scattering problems. The effect of long-range interactions is also discussed, with special attention paid to the appearance of an effective Wigner regime for elastic scattering in certain partial waves.

  20. Production of hydrogen for fuel cells by catalytic partial oxidation of ethanol over structured Ru catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Liguras, D.K.; Goundani, K.; Verykios, X.E. [University of Patras (Greece). Dept. of Chemical Engineering

    2004-03-01

    A series of Ru catalysts supported on cordierite monoliths, ceramic foams and {gamma}-Al{sub 2}O{sub 3} pellets were prepared and tested for the production of hydrogen by catalytic partial oxidation of ethanol. The catalyst supported on a cordierite monolith exhibited excellent catalytic performance for a wide variety of process conditions and excellent long-term stability with low coke formation. The effect of the steam to ethanol molar ratio on conversion and selectivities was relatively small. A more pronounced effect was observed for the oxygen to ethanol ratio. Overall, catalysts on all three supports were able to completely convert ethanol with high selectivities towards the desired products. The Ru supported on a ceramic foam catalyst provided comparatively better performance, probably due to the smaller pore sizes and higher tortuosity of this support. (author)

  1. Hydro-isomerization of n-hexane on bi-functional catalyst: Effect of total and hydrogen partial pressures

    Science.gov (United States)

    Thoa, Dao Thi Kim; Loc, Luu Cam

    2017-09-01

    The effect of both total pressure and hydrogen partial pressure during n-hexane hydro-isomerization over platinum impregnated on HZSM-5 was studied. n-Hexane hydro-isomerization was conducted at atmospheric pressure and 0.7 MPa to observe the influence of total pressure. In order to see the effect of hydrogen partial pressure, the reaction was taken place at different partial pressure of hydrogen varied from 307 hPa to 718 hPa by dilution with nitrogen to keep the total pressure at 0.1 MPa. Physico-chemical characteristics of catalyst were determined by the methods of nitrogen physi-sorption BET, SEM, XRD, TEM, NH3-TPD, TPR, and Hydrogen Pulse Chemi-sorption. Activity of catalyst in the hydro-isomerization of n-hexane was studied in a micro-flow reactor in the temperature range of 225-325 °C; the molar ratio H2/ hydrocarbon: 5.92, concentration of n-hexane: 9.2 mol.%, GHSV 2698 h-1. The obtained catalyst expressed high acid density, good reducing property, high metal dispersion, and good balance between metallic and acidic sites. It is excellent contact for n-hexane hydro-isomerization. At 250 °C, n-hexane conversion and selectivity were as high as 59-76 % and 85-99 %, respectively. It was found that catalytic activity was promoted either by total pressure or hydrogen partial pressure. At total pressure of 0.7 MPa while hydrogen partial pressure of 718 hPa, catalyst produced 63 RON liquid product containing friendly environmental iso-paraffins which is superior blending stock for green gasoline. Hydrogen did not only preserve catalyst actives by depressing hydrocracking and removing coke precursors but also facilitated hydride transfer step in the bi-functional bi-molecular mechanism.

  2. Partial Hydrogenation of Calophyllum Inophyllum Methyl Esters to Increase the Oxidation Stability

    Directory of Open Access Journals (Sweden)

    Joelianingsih

    2015-10-01

    Full Text Available Calophyllum inophyllum methyl esters have a low oxidation stability value (5-6 h caused by high amounts of polyunsaturated fatty acid methyl esters (FAME, especially methyl linoleate. Partial hydrogenation was done to reduce the number of polyunsaturated FAME to transform them into mono-unsaturated. This was performed at 6 bar and 900 rpm with Pd/Al2O3 solid catalyst in a reactor with a capacity of 1 liter. The research purpose was to learn the effects of reaction temperature (80; 100; 120°C and time (1; 1.5; 2 h on the FAME composition. The optimum condition of the experiment was obtained at 120°C for 1 h, with 15.47 h as the oxidation stability value, 17.8°C as the cloud point value, and 51.17 as the cetane number. Under this condition, the methyl linoleate content decreased by 59.89% w/w (from 21.869% to 8,770% w/w and methyl linoleate hydrogenated into methyl elaidate. Meanwhile, the methyl linolenate content decreased by 85,37% w/w (from 0.205% to 0.030% w/w and methyl linolenate hydrogenated into methyl linolelaidate. These results show that the research met the following standards: a minimum oxidation stability value of 10 h in accordance with the World Wide Fuel Charter (WWFC 2009, a maximum cloud point value of 18°C and a minimum cetane number 51 in accordance with SNI 7182-2012. The physical properties values of the Calophyllum inophyllum methyl esters were predicted using the empirical equations.

  3. Association between hepatic cholesterol and oleic acid in the liver of rats treated with partially hydrogenated vegetable oil

    OpenAIRE

    Castro, Gabriela Salim Ferreira de; Almeida, Bianca Bellizzi de; Carvalho, Daphne Santoro Leonardi de; Ovidio, Paula Payão; Jordao Junior, Alceu Afonso

    2012-01-01

    Objective The aim of the present study was to investigate the lipid profiles of the hepatic and adipose tissues of Wistar rats treated for 21 days with a diet high in saturated fat (high saturated fat, n=6) or high in hydrogenated fat, that is, having 50% partially hydrogenated vegetable oil in its composition (high hydrogenated fat, n=6), and compare them to those of a control group (control group, n=6). Methods Adipose tissue and total hepatic fat were higher in the saturated fat group than...

  4. Hydrogen production by partial oxidation of methanol over gold supported on Fe2O3.

    Science.gov (United States)

    Roselin, L Selva; Liao, Li-Mei; Ou, You-Chen; Chang, Feg-Wen

    2014-09-01

    Partial oxidation of methanol (POM) to produce hydrogen was investigated over Au/Fe2O3 catalysts. The catalysts were prepared by inverse co-precipitation method. The influence of catalyst synthesis parameters such as precipitant, gold loading, calcination temperature and reaction parameter such as reaction temperature on POM reaction to produce hydrogen were investigated. The catalysts have been characterized by means of TGA, BET, XRD, TEM, SEM-EDS and XPS analyses. TGA and DTGA profiles clearly indicate that minimum decomposition temperature required to obtain Fe2O3 in Au/Fe2O3 catalysts is 660 K. SEM-EDS analysis confirms that Au and Fe in Au/Fe2O3 are homogeneously distributed over the agglomerate. A detailed microstuctural characterization of Au/Fe2O3 sample by XRD, TEM and XPS analyses has shown that nanometer sized gold particles with oxidized gold species is in predominant amount in the uncalcined catalysts sample. The mean particle size and metallic state of gold particles increase with increasing calcination temperature. A highly active Au/Fe2O3 catalyst is obtained by using Na2CO3 as precipitant with lower gold loading and calcination at 673 K. The catalytic behavior of the Au/Fe2O3 catalyst is related not only to the gold but also to the chemical state of the support. The effect of reaction temperature on the catalytic performance of the Au/Fe2O3 catalysts was studied in the temperature range of 423 to 523 K. Oxygen conversion was complete through out the examined temperature range. Methanol conversion increased with rise in temperature and attains 100% at 503 K; Hydrogen selectivity increased with rise in reaction temperature up to 523 K and then dropped off. The overall reactions involved are methanol combustion, partial oxidation, steam reforming and decomposition. CO produced by methanol decomposition and/or by reverse water gas shift is subsequently transformed into CO2 and H2 by the water gas shift and/or CO oxidation.

  5. A novel technique for hydrogen production from hog-manure in supercritical partial oxidation (SCWPO)

    Energy Technology Data Exchange (ETDEWEB)

    Youssef, Emhemmed A.; Charpentier, Paul [Western Ontario Univ., London, ON (Canada). Dept. of Chemical and Biochemical Engineering; Nakhla, George [Western Ontario Univ., London, ON (Canada). Dept. of Chemical and Biochemical Engineering; Western Ontario Univ., London, ON (Canada). Dept. of Civil and Environmental Engineering; Elbeshbishy, Elsayed; Hafez, Hisham [Western Ontario Univ., London, ON (Canada). Dept. of Civil and Environmental Engineering

    2010-07-01

    In this study, the catalytic hydrogen production from hog manure using supercritical water partial oxidation was investigated in a batch reactor at a temperature of 500 C, and pressure of 28 MPa using several metallic catalysts. Hog manure was characterized by a total and soluble chemical oxygen demand (TCOD, SCOD) of 57000 and 28000 mg/L, total and volatile suspended solids (TSS, VSS) of 25000, 19000, and ammonia of 2400 mg/L, respectively. The order of H{sub 2} production was the following: Pd/AC > Ru/Al{sub 2}O{sub 3} > Ru/AC > AC > NaOH. The order of COD reduction efficiency was as follows: NaOH > Ru/AC > AC > Ru/Al{sub 2}O{sub 3} > Pd/AC. The behaviour of the volatile fatty acids (VFA's), ethanol, methanol, ammonia, H{sub 2}S, and Sulfate was investigated experimentally and discussed. A 35 % reduction in the H{sub 2} and CH{sub 4} yields was observed in the sequential gasification partial oxidation (oxidant at an 80 % of theoretical requirement) experiments compared to the gasification experiments (catalyst only). Moreover, this reduction in gas yields was coincided with a 45 % reduction in the liquid effluent chemical oxygen demand (COD), 60 % reduction of the ammonia concentration in the liquid effluent, and 20 % reduction in the H{sub 2}S concentration in the effluent gas. (orig.)

  6. The Influence of Injection Timing on Performance Characteristics of Diesel Engine Using Jatropha Biodiesel with and without Partial Hydrogenation

    Directory of Open Access Journals (Sweden)

    Rizqon Fajar

    2014-07-01

    Full Text Available Experimental research has been conducted to investigate the effects of blend of hydrogenated and unhydrogenated Jatropha biodiesel with diesel fuel in volume ratio of 30:70 (B30 on combustion characteristics (BSFC, thermal efficiency and smoke emission of single cylinder diesel engine. In this experiment, engine speed was kept constant at 1,500, 2,500, and 3,500 rpm with maximum engine load at BMEP 5 bar and injection timings were varied. Experimental result showed that at engine speed 1,500 rpm, BSFC of B30 hydrogenated and unhydrogenated Jatropha biodiesel were higher than it of diesel fuel at all injection timings (10° to 18° BTDC. At the same condition, partial hydrogenated Jatropha biodiesel showed higher BSFC than unhydrogenated Jatropha biodiesel. However, the difference in BSFC became smaller for all fuels at engine speed 2,500 rpm and 3,500 rpm at all injection timing. Jatropha biodiesel with and without partial hydrogenation tend to have higher thermal efficiency compared with diesel fuel at all engine speed and injection timing. The best injection timings to operate B30 Jatropha biodiesel with and without hydrogenation were 14°, 18° and 24° BTDC at engine speed 1,500, 2,500, and 3,500 rpm respectively. This conclusion was deduced based on the minimum value of BSFC and the maximum value of thermal efficiency. Smoke emissions for all fuels were in the same level for all conditions.

  7. The influence of natural tocopherols during thermal oxidation of refined and partially hydrogenated soybean oils

    Directory of Open Access Journals (Sweden)

    Barrera-Arellano, D.

    2005-03-01

    Full Text Available Samples of refined and partially hydrogenated soybean oils, with iodine values between 60 and 130, tocopherol-stripped or not by aluminium oxide treatment, were submitted to thermal oxidation, at 180 °C (during for 10 hours. Samples were collected at 0, 2, 5, 8 and 10 hours, for the determination of dimers and polymers (degradation compounds and tocopherols. The relation of iodine value to the formation of dimers and polymers and the role of originally present tocopherols in the protection of fats and oils against thermal degradation was verified. The degradation curves for tocopherols showed that α and γ -tocopherols were destroyed faster than β and δ -tocopherols. In addition, the degradation rate of tocopherols was greater in the more saturated fats. The formation of dimers and polymers was greater in the oil than in the hydrogenated samples and in the samples treated with aluminium oxide with respect to the original, untreated samples.Muestras de aceites refinados y parcialmente hidrogenados de soja, con índices de yodo entre 60 y 130, tratadas o no con óxido de aluminio para eliminar los tocoferoles naturales presentes en los aceites, fueron sometidas a termoxidación, a 180 °C durante 10 horas. Se tomaron muestras en los tiempos 0, 2, 5, 8 y 10 horas, para determinación de dímeros y polímeros (compuestos de degradación y de tocoferoles. Se verificó la relación del índice de yodo con la formación de dímeros y polímeros, y también el papel de los tocoferoles originales del aceite y de las grasas en la protección contra la degradación térmica. Las curvas de degradación de los tocoferoles mostraron la destrucción más rápida de α y γ -tocoferoles, respecto a β y δ-tocoferoles. Además, la degradación de los tocoferoles ocurrió a mayor velocidad en las grasas más saturadas. La formación de dímeros y polímeros fue mayor en el aceite que en las muestras hidrogenadas y en las muestras tratadas

  8. Characteristics of hydrogen produced by partial oxidation and auto-thermal reforming in a small methanol reformer

    Science.gov (United States)

    Horng, Rong-Fang; Chou, Huann-Ming; Lee, Chiou-Hwang; Tsai, Hsien-Te

    This paper investigates experimentally, the transient characteristics of a small methanol reformer using partial oxidation (POX) and auto-thermal reforming (ATR) for fuel cell applications. The parameters varied were heating temperature, methanol supply rate, steady mode shifting temperature, O 2/C (O 2/CH 3OH) and S/C (H 2O/CH 3OH) molar ratios with the main aim of promoting a rapid response and a high flow rate of hydrogen. The experiments showed that a high steady mode shifting temperature resulted in a faster temperature rise at the catalyst outlet and vice versa and that a low steady mode shifting temperature resulted in a lower final hydrogen concentration. However, when the mode shifting temperature was too high, the hydrogen production response was not necessarily improved. It was subsequently shown that the optimum steady mode shifting temperature for this experimental set-up was approximately 75 °C. Further, the hydrogen concentration produced by the auto-thermal process was as high as 49.12% and the volume flow rate up to 23.0 L min -1 compared to 40.0% and 20.5 L min -1 produced by partial oxidation.

  9. THE WILKINSON COMPLEX AS A HETEROGENEOUS CATALYST IN THE PARTIAL HYDROGENATION OF 1-HEPTYNE. REGENERATION OF THE COMPLEX

    Directory of Open Access Journals (Sweden)

    Edgardo Cagnola

    2016-06-01

    Full Text Available The Wilkinson complex was tested as a catalyst in the partial hydrogenation of 1-heptyne, a medium chain alkyne, at a temperature of T = 303 K and hydrogen pressure PH2 = 150 kPa. The tests were performed in homogeneous system as well as heterogeneous system, supporting the complex on i γ-Al2O3 and ii a commercial carbonaceous material, RX3. Characterization by means of XPS and FTIR revealed that the anchored complex did not lose its chemical identity, being the catalytically active species. The Wilkinson complex on RX3 showed better conversions and selectivities, higher than the Lindlar catalyst, used as a reference. Additionally, it was proposed a method to recover Rh as a metal from the remaining solutions, and from it regenerate the complex to be reused from it.

  10. Hydrogen or Soot?: Partial Oxidation of High-boiling Hydrocarbon Wastes

    Czech Academy of Sciences Publication Activity Database

    Lederer, J.; Hanika, Jiří; Nečesaný, F.; Poslední, W.; Tukač, V.; Veselý, Václav

    2015-01-01

    Roč. 29, č. 1 (2015), s. 5-11 ISSN 0352-9568 Institutional support: RVO:67985858 Keywords : partial oxidation * waste * hydrocarbon Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.675, year: 2015

  11. Phase shifts and the second virial coefficient for a partially ionized hydrogen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Omarbakiyeva, Y.A. [Institut fuer Physik, Universitaet Rostock, 18051 Rostock (Germany); IETP, al-Farabi Kazakh National University, 96a Tole bi str., 050012 Almaty (Kazakhstan); Roepke, G. [Institut fuer Physik, Universitaet Rostock, 18051 Rostock (Germany); Ramazanov, T.S. [IETP, al-Farabi Kazakh National University, 96a Tole bi str., 050012 Almaty (Kazakhstan)

    2009-12-15

    The influence of the interaction of electrons with hydrogen atoms on the thermodynamical properties of dense plasmas is investigated using a virial expansion approach. The second virial coefficient for the electron-atom interaction is obtained from the Beth-Uhlenbeck formula. Elastic scattering phase shifts are calculated with the help of the phase function method for different polarization potential models. Results for the second virial coefficient are given that take into account both the bound state part and the scattering state contribution (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  12. Ionization cross section for a strongly coupled partially ionized hydrogen plasma: variable phase approach

    Energy Technology Data Exchange (ETDEWEB)

    Baimbetov, F B; Kudyshev, Z A [Department of Physics, Al-Farabi Kazakh National University, 050012 Almaty (Kazakhstan)], E-mail: Fazylhan.Baimbetov@kaznu.kz, E-mail: Z.Kudyshev@mail.ru

    2009-05-29

    In the present work an electron impact ionization cross section is considered. The electron impact ionization cross section is calculated with the help of a variable phase approach to potential scattering. The Calogero equation is numerically solved, based on a pseudopotential model of interaction between partially ionized plasma particles, which accounts for correlation effects. As a result, scattering phase shifts are obtained. On the basis of the scattering phase shifts, the ionization cross section is calculated.

  13. Enzymatic production of trans fatty acid free fat from partially hydrogenated soybean oil (PHSO)--theory, strategy and practicability.

    Science.gov (United States)

    Jala, Ram Chandra Reddy; Xu, Xuebing; Guo, Zheng

    2013-12-01

    Development of an advanced process/production technology for healthful fats constitutes a major interest of plant oil refinery industry. In this work, a strategy to produce trans fatty acid (TFA) free (or low TFA) products from partially hydrogenated soybean oil by lipase-catalysed selective hydrolysis was proposed, where a physically founded mathematic model to delineate the multi-responses of the reaction as a function of selectivity factor was defined for the first time. The practicability of this strategy was assessed with commercial trans-selective Candida antarctica lipase A (CAL-A) as a model biocatalyst based on a parameter study and fitting to the model. CAL-A was found to have a selectivity factor 4.26 and to maximally remove 73.3% of total TFAs at 46.5% hydrolysis degree. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Partial Oxidation Gas Turbine for Power and Hydrogen Co-Production from Coal-Derived Fuel in Industrial Applications

    Energy Technology Data Exchange (ETDEWEB)

    Joseph Rabovitser

    2009-06-30

    The report presents a feasibility study of a new type of gas turbine. A partial oxidation gas turbine (POGT) shows potential for really high efficiency power generation and ultra low emissions. There are two main features that distinguish a POGT from a conventional gas turbine. These are associated with the design arrangement and the thermodynamic processes used in operation. A primary design difference of the POGT is utilization of a non?catalytic partial oxidation reactor (POR) in place of a conventional combustor. Another important distinction is that a much smaller compressor is required, one that typically supplies less than half of the air flow required in a conventional gas turbine. From an operational and thermodynamic point of view a key distinguishing feature is that the working fluid, fuel gas provided by the OR, has a much higher specific heat than lean combustion products and more energy per unit mass of fluid can be extracted by the POGT expander than in the conventional systems. The POGT exhaust stream contains unreacted fuel that can be combusted in different bottoming ycle or used as syngas for hydrogen or other chemicals production. POGT studies include feasibility design for conversion a conventional turbine to POGT duty, and system analyses of POGT based units for production of power solely, and combined production of power and yngas/hydrogen for different applications. Retrofit design study was completed for three engines, SGT 800, SGT 400, and SGT 100, and includes: replacing the combustor with the POR, compressor downsizing for about 50% design flow rate, generator replacement with 60 90% ower output increase, and overall unit integration, and extensive testing. POGT performances for four turbines with power output up to 350 MW in POGT mode were calculated. With a POGT as the topping cycle for power generation systems, the power output from the POGT ould be increased up to 90% compared to conventional engine keeping hot section temperatures

  15. Hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Pier, M.

    1943-02-19

    A transcript is presented of a speech on the history of the development of hydrogenation of coal and tar. Apparently the talk had been accompanied by the showing of photographic slides, but none of the pictures were included with the report. In giving the history, Dr. Pier mentioned the dependence of much of the development of hydrogenation upon previous development in the related areas of ammonia and methanol syntheses, but he also pointed out several ways in which equipment appropriate for hydrogenation differed considerably from that used for ammonia and methanol. Dr. Pier discussed the difficulties encountered with residue processing, design of the reaction ovens, manufacture of ovens and preheaters, heating of reaction mixtures, development of steels, and development of compressor pumps. He described in some detail his own involvement in the development of the process. In addition, he discussed the development of methods of testing gasolines and other fuels. Also he listed some important byproducts of hydrogenation, such as phenols and polycyclic aromatics, and he discussed the formation of iso-octane fuel from the butanes arising from hydrogenation. In connection with several kinds of equipment used in hydrogenation (whose pictures were being shown), Dr. Pier gave some of the design and operating data.

  16. Temperature-Induced Misfolding in Prion Protein: Evidence of Multiple Partially Disordered States Stabilized by Non-Native Hydrogen Bonds.

    Science.gov (United States)

    Chamachi, Neharika G; Chakrabarty, Suman

    2017-02-14

    The structural basis of pathways of misfolding of a cellular prion (PrPC) into the toxic scrapie form (PrPSC) and identification of possible intermediates (e.g., PrP*) still eludes us. In this work, we have used a cumulative ∼65 μs of replica exchange molecular dynamics simulation data to construct the conformational free energy landscapes and capture the structural and thermodynamic characteristics associated with various stages of the thermal denaturation process in human prion protein. The temperature-dependent free energy surfaces consist of multiple metastable states stabilized by non-native contacts and hydrogen bonds, thus rendering the protein prone to misfolding. We have been able to identify metastable conformational states with high β-content (∼30-40%) and low α-content (∼10-20%) that might be precursors of PrPSC oligomer formation. These conformations also involve participation of the unstructured N-terminal domain, and its role in misfolding has been investigated. All the misfolded or partially unfolded states are quite compact in nature despite having large deviations from the native structure. Although the number of native contacts decreases dramatically at higher temperatures, the radius of gyration and number of intraprotein hydrogen bonds and contacts remain relatively unchanged, leading to stabilization of the misfolded conformations by non-native interactions. Our results are in good agreement with the established view that the C-terminal regions of the second and third helices (H2 and H3, respectively) of mammal prions might be the Achilles heels of their stability, while separation of B1-H1-B2 and H2-H3 domains seems to play a key role, as well.

  17. Hydrogen.

    Science.gov (United States)

    Bockris, John O'M

    2011-11-30

    The idea of a "Hydrogen Economy" is that carbon containing fuels should be replaced by hydrogen, thus eliminating air pollution and growth of CO₂ in the atmosphere. However, storage of a gas, its transport and reconversion to electricity doubles the cost of H₂ from the electrolyzer. Methanol made with CO₂ from the atmosphere is a zero carbon fuel created from inexhaustible components from the atmosphere. Extensive work on the splitting of water by bacteria shows that if wastes are used as the origin of feed for certain bacteria, the cost for hydrogen becomes lower than any yet known. The first creation of hydrogen and electricity from light was carried out in 1976 by Ohashi et al. at Flinders University in Australia. Improvements in knowledge of the structure of the semiconductor-solution system used in a solar breakdown of water has led to the discovery of surface states which take part in giving rise to hydrogen (Khan). Photoelectrocatalysis made a ten times increase in the efficiency of the photo production of hydrogen from water. The use of two electrode cells; p and n semiconductors respectively, was first introduced by Uosaki in 1978. Most photoanodes decompose during the photoelectrolysis. To avoid this, it has been necessary to create a transparent shield between the semiconductor and its electronic properties and the solution. In this way, 8.5% at 25 °C and 9.5% at 50 °C has been reached in the photo dissociation of water (GaP and InAs) by Kainthla and Barbara Zeleney in 1989. A large consortium has been funded by the US government at the California Institute of Technology under the direction of Nathan Lewis. The decomposition of water by light is the main aim of this group. Whether light will be the origin of the post fossil fuel supply of energy may be questionable, but the maximum program in this direction is likely to come from Cal. Tech.

  18. Regiospecific Distribution of trans-Octadecenoic Acid Positional Isomers in Triacylglycerols of Partially Hydrogenated Vegetable Oil and Ruminant Fat.

    Science.gov (United States)

    Yoshinaga, Kazuaki; Kawamura, Yoshinori; Kitayama, Takashi; Nagai, Toshiharu; Mizobe, Hoyo; Kojima, Koichi; Watanabe, Yomi; Sato, Shinichi; Beppu, Fumiaki; Gotoh, Naohiro

    2015-01-01

    It is revealed that binding position of fatty acid in triacylglycerol (TAG) deeply relates to the expression of its function. Therefore, we investigated the binding positions of individual trans-octadecenoic acid (trans-C18:1) positional isomers, known as unhealthy fatty acids, on TAG in partially hydrogenated canola oil (PHCO), milk fat (MF), and beef tallow (BT). The analysis was carried out by the sn-1(3)-selective transesterification of Candida antarctica Lipase B and by using a highly polar ionic liquid capillary column for gas chromatography-flame ionization detection. Trans-9-C18:1, the major trans-C18:1 positional isomer, was selectively located at the sn-2 position of TAG in PHCO, although considerable amounts of trans-9-C18:1 were also esterified at the sn-1(3) position. Meanwhile, trans-11-C18:1, the major isomer in MF and BT, was preferentially located at the sn-1(3) position. These results revealed that the binding position of trans-C18:1 positional isomer varies between various fats and oils.

  19. Formation of polymerization compounds during thermal oxidation of cottonseed oil, partially hydrogenated cottonseed oil and their blends

    Directory of Open Access Journals (Sweden)

    Barrera-Arellano, D. Laboratório de Óleos e Gorduras, Departa

    2006-09-01

    Full Text Available Samples of cottonseed oil, partially hydrogenated cottonseed oil and their blends, with iodine values between 60 and 110, tocopherol-stripped or not by aluminium oxide treatment, were submitted to thermal oxidation, at 180 °C, for 10 hours. Samples were collected at 0, 2, 5, 8 and 10 hours, for the determination of dimers and polymers (degradation compounds and of tocopherols. The influence of the degree of hydrogenation on the formation of dimers and polymers and the role of originally present tocopherols in the protection of fats and oils against thermal degradation was verified. The degradation curves for tocopherols showed a fast destruction rate for the tocopherols present in cottonseed fats and oil (α and γ-tocopherols, with residual levels close to zero after 10 hours under thermal oxidation conditions. Nevertheless, samples with their natural tocopherols presented a slower rate of thermal degradation. The unsaturation degree was apparently more important in the protection against thermal degradation than the content of tocopherolsMuestras de aceite de algodón, aceite de algodón parcialmente hidrogenado y sus mezclas, con índices de yodo de 60 a 110, tratadas o no con óxido de aluminio, fueron sometidas a termoxidación, a 180 °C, durante 10 horas. Se retiraron muestras en los tiempos 0, 2, 5, 8 y 10 horas, para determinación de dímeros y polímeros (compuestos de degradación y de tocoferoles. Se verificó la influencia del grado de hidrogenación sobre la formación de dímeros y polímeros, y también el papel de los tocoferoles originalmente presentes en el aceite y en las grasas, en la protección contra la degradación térmica. Las curvas de degradación de los tocoferoles mostraron una destrucción bastante rápida de los tocoferoles presentes en el aceite y en las grasas de algodón (α y γ-tocoferoles, con niveles residuales próximos a cero después de 10 horas de termoxidación. Aún así, muestras con sus

  20. Hydrogen

    Directory of Open Access Journals (Sweden)

    John O’M. Bockris

    2011-11-01

    Full Text Available The idea of a “Hydrogen Economy” is that carbon containing fuels should be replaced by hydrogen, thus eliminating air pollution and growth of CO2 in the atmosphere. However, storage of a gas, its transport and reconversion to electricity doubles the cost of H2 from the electrolyzer. Methanol made with CO2 from the atmosphere is a zero carbon fuel created from inexhaustible components from the atmosphere. Extensive work on the splitting of water by bacteria shows that if wastes are used as the origin of feed for certain bacteria, the cost for hydrogen becomes lower than any yet known. The first creation of hydrogen and electricity from light was carried out in 1976 by Ohashi et al. at Flinders University in Australia. Improvements in knowledge of the structure of the semiconductor-solution system used in a solar breakdown of water has led to the discovery of surface states which take part in giving rise to hydrogen (Khan. Photoelectrocatalysis made a ten times increase in the efficiency of the photo production of hydrogen from water. The use of two electrode cells; p and n semiconductors respectively, was first introduced by Uosaki in 1978. Most photoanodes decompose during the photoelectrolysis. To avoid this, it has been necessary to create a transparent shield between the semiconductor and its electronic properties and the solution. In this way, 8.5% at 25 °C and 9.5% at 50 °C has been reached in the photo dissociation of water (GaP and InAs by Kainthla and Barbara Zeleney in 1989. A large consortium has been funded by the US government at the California Institute of Technology under the direction of Nathan Lewis. The decomposition of water by light is the main aim of this group. Whether light will be the origin of the post fossil fuel supply of energy may be questionable, but the maximum program in this direction is likely to come from Cal. Tech.

  1. Hydrogen production by ethanol partial oxidation over nano-iron oxide catalysts produced by chemical vapour synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Wael Ahmed Abou Taleb Sayed

    2011-01-13

    This work presents the experimental results of the synthesis of unsupported and supported SiC iron oxide nanoparticles and their catalytic activity towards ethanol partial oxidation. For comparison, further unsupported iron oxide phases were investigated towards the ethanol partial oxidation. These {gamma}-Fe{sub 2}O{sub 3} and {alpha}/{gamma}-Fe{sub 2}O{sub 3} phase catalysts were prepared by the CVS method using Fe(CO){sub 5} as precursor, supplied by another author. The {alpha}-Fe{sub 2}O{sub 3} and SiC nanoparticles were prepared by the CVS method using a home made hot wall reactor technique at atmospheric pressure. Ferrocene and tetramethylsilane were used as precursor for the production process. Process parameters of precursor evaporation temperature, precursor concentration, gas mixture velocity and gas mixture dilution were investigated and optimised to produce particle sizes in a range of 10 nm. For Fe{sub 2}O{sub 3}/SiC catalyst series production, a new hot wall reactor setup was used. The particles were produced by simultaneous thermal decomposition of ferrocene and tetramethylsilane in one reactor from both sides. The production parameters of inlet tube distance inside the reactor, precursor evaporation temperature and carrier gas flow were investigated to produce a series of samples with different iron oxide content. The prepared catalysts composition, physical and chemical properties were characterized by XRD, EDX, SEM, BET surface area, FTIR, XPS and dynamic light scattering (DLS) techniques. The catalytic activity for the ethanol gas-phase oxidation was investigated in a temperature range from 260 C to 290 C. The product distributions obtained over all catalysts were analysed with mass spectrometry analysis tool. The activity of bulk Fe{sub 2}O{sub 3} and SiC nanoparticles was compared with prepared nano-iron oxide phase catalysts. The reaction parameters, such as reaction temperature and O{sub 2}/ethanol ratio were investigated. The catalysts

  2. The role of sulfur trapped in micropores in the catalytic partial oxidation of hydrogen sulfide with oxygen

    NARCIS (Netherlands)

    Steijns, M.; Mars, P.

    1974-01-01

    The catalytic oxidation of hydrogen sulfide into sulfur with molecular oxygen has been studied in the temperature range 130–200 °C. Active carbon, molecular sieve 13X and liquid sulfur were used as catalysts. Sulfur is adsorbed in the micropores (3 < r < 40 Å) of the catalysts. Experiments with a

  3. Allelic variation partially regulates galactose-dependent hydrogen peroxide release from circulating hemocytes of the snail Biomphalaria glabrata.

    Science.gov (United States)

    Allan, Euan R O; Blouin, Michael S

    2018-01-01

    Freshwater snails are the intermediate hosts for numerous parasitic worms that are detrimental to human and agricultural health. Understanding the immune responses of these snails could be vital for finding ways to block transmission of those parasites. Allelic variation in a recently discovered genomic region in the snail, Biomphalaria glabrata, influences their susceptibility to schistosomes. Here we tested whether genes in that region, termed the Guadeloupe Resistance Complex (GRC), are involved in recognition of common pathogen-associated molecules that have been shown to be stimulants of the hydrogen peroxide defense pathway. We show that hemocytes extracted from individuals with one of the three GRC genotypes released less hydrogen peroxide than the other two genotypes, after stimulation with galactose. This difference was not observed after stimulation with several other microbial-associated carbohydrates, despite those ligands sharing the same putative pathway for hydrogen peroxide release. Therefore, we conclude that allelic variation in the GRC region may influence the recognition of galactose, rather than the conserved downstream steps in the hydrogen peroxide pathway. These results thus are consistent with the hypothesis that proteins produced by this region are involved in pathogen recognition. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Morbidade da biópsia da próstata transretal guiada por ultrassonografia

    Directory of Open Access Journals (Sweden)

    Raphael Sandes Solha

    2013-04-01

    Full Text Available OBJETIVO: Avaliar a incidência de complicações pós-procedimento nos pacientes submetidos a biópsia prostática transretal guiada por ultrassom no setor de intervenção do Departamento de Diagnóstico por Imagem da Escola Paulista de Medicina - Universidade Federal de São Paulo. MATERIAIS E MÉTODOS: Foram avaliados, via contato telefônico, 132 pacientes submetidos a biópsia de próstata transretal guiada por ultrassom no período de abril/2011 a junho/2011, seguindo o protocolo padrão do nosso setor. RESULTADOS: As complicações pós-biópsia foram categorizadas em maiores e menores de acordo com a necessidade de avaliação médica adicional. Cinquenta e nove pacientes (61,8% apresentaram complicações, e desses, grande parte (86,4% apresentou sintomas leves e autolimitados, considerados menores. Oito pacientes (8,2% apresentaram complicações maiores, sendo que apenas um deles necessitou de tratamento sob regime de internação hospitalar. A retenção urinária foi a complicação maior mais incidente no nosso estudo. CONCLUSÃO: Corroborando outros estudos da literatura, nosso trabalho demonstrou baixa prevalência de complicações maiores após a biópsia prostática transretal.

  5. Production of cobalt-copper from partial reduction of La(Co,CuO3 perovskites for CO hydrogenation

    Directory of Open Access Journals (Sweden)

    Nguyen Tien Thao

    2016-09-01

    Full Text Available La(CoCuO3 nanoperovskites have been prepared by the mechano-synthesis method and treated with hydrogen to yield a high dispersion of bimetallic CoCu sites. The reduced LaCo1-xCuxO3 samples were characterized by XRD, H2-TPR, CO and H2 chemisorption and tested for CO dissociation and for alcohol synthesis from syngas. The experimental results indicated that the activities in CO dissociation and hydrogenation on copper-cobalt metals extracted from perovskite lattice crystals are significantly different from those in the extra-perovskite lattice. The overall catalytic activity in syngas conversion is correlated with the CoCu metal surface, but the alcohol productivity e productivity of alcohols decreases in the order of LaCo0.7Cu0.3O3 > LaCo0.4Cu0.6O3 > Cu2O/LaCoO3 > LaCo0.9Cu0.1O3 > LaCoO3. The highest catalytic activity and alcohol productivity was obtained over sample of the reduced LaCo0.7Cu0.3O3 perovskite catalyst.

  6. Process for desulphurisation of liquid commercial fuels for applications in fuel cell systems by partial evaporation followed by hydrogenating desulphurisation; Verfahren zur Entschwefelung von fluessigen handelsueblichen Brennstoffen fuer die Anwendung in Brennstoffzellensystemen durch partielle Verdampfung und anschliessende hydrierende Entschwefelung

    Energy Technology Data Exchange (ETDEWEB)

    Brune, Markus

    2010-07-01

    Desulphurisation of commercial liquid fuels by partial evaporation followed by hydrogenating desulphurisation is a promising process for decentral fuel cell systems. This is a newly developed process in which only the fraction to be used in the fuel cell is evaporated and is then desulphurized in the gaseous phase using recycled hydrogen from combustion gas production. The residue of the partial evaporation can be recirculated either directly into a reformer burner of an allothermal steam reforming process, into a heating burner, into an engine, or into a storage tank depending on the intended application. The publication also takes a short look at other desulphurisation processes and attempts a comparison. The results of hydrogenating desulphurisation of partially evaporated kerosene and heating oil using a CoMo catalyst illustrate the feasibility of the process. Most of the sulphur compounds are converted, and the end product has sufficient purity for application in a fuel cell process, i.e. less than ppm. (orig./MM)

  7. STRUCTURAL INTERACTIONS OF HYDROGEN WITH BULK AMORPHOUS MICROSTRUCTURES IN METALLIC SYSTEMS UNDERSTANDING THE ROLE OF PARTIAL CRYSTALLINITY ON PERMEATION AND EMBRITTLEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Brinkman, Kyle; Fox, Elise; Korinko, Paul; Adams, Thad

    2010-05-10

    The development of metallic glasses in bulk form has led to a resurgence of interest into the utilization of these materials for a variety of applications. A potentially exciting application for these bulk metallic glass (BMG) materials is their use as composite membranes to replace high cost Pd/Pd-alloy membranes for enhanced gas separation processes. One of the major drawbacks to the industrial use of Pd/Pd-alloy membranes is that during cycling above and below a critical temperature an irreversible change takes place in the palladium lattice structure which can result in significant damage to the membrane. Furthermore, the cost associated with Pd-based membranes is a potential detractor for their continued use and BMG alloys offer a potentially attractive alternative. Several BMG alloys have been shown to possess high permeation rates, comparable to those measured for pure Pd metal. In addition, high strength and toughness when either in-situ or ex-situ second phase dispersoids are present. Both of these properties, high permeation and high strength/toughness, potentially make these materials attractive for gas separation membranes that could resist hydrogen 'embrittlement'. However, a fundamental understanding of the relationship between partially crystalline 'structure'/devitrification and permeation/embrittlement in these BMG materials is required in order to determine the operating window for separation membranes and provide additional input to the material synthesis community for improved alloy design. This project aims to fill the knowledge gap regarding the impact of crystallization on the permeation properties of metallic glass materials. The objectives of this study are to (i) determine the crystallization behavior in different gas environments of Fe and Zr based commercially available bulk metallic glass and (ii) quantify the effects of partial crystallinity on the hydrogen permeation properties of these metallic glass membranes.

  8. NHETS - Estudo de Necrópsias de Pacientes Submetidos a Transplante Cardíaco

    Directory of Open Access Journals (Sweden)

    Thiago Ninck Valette

    2014-06-01

    Full Text Available Fundamento: Discordâncias entre diagnóstico pre e post-mortem são relatadas na literatura, podendo variar de 4,1 a 49,8% dentre os casos encaminhados para exame necroscópico, com importante repercussão no tratamento dos pacientes. Objetivo: Analisar pacientes com óbito após o transplante cardíaco e confrontar os diagnósticos pre e post-mortem. Métodos: Por meio da revisão de prontuários, foram analisados dados clínicos, presença de comorbidades, esquema de imunossupressão, exames laboratoriais, causa clínica do óbito e causa do óbito à necrópsia. Foram confrontadas, então, a causa clínica e a causa necroscópica do óbito de cada paciente. Resultados: Foram analisados 48 óbitos submetidos à necrópsia no período de 2000 a 2010; 29 (60,4% tiveram diagnósticos clínico e necroscópico concordantes, 16 (33,3% tiveram diagnósticos discordantes e três (6,3% tiveram diagnóstico não esclarecido. Entre os discordantes, 15 (31,3% apresentaram possível impacto na sobrevida e um (2,1% não apresentou impacto na sobrevida. O principal diagnóstico clínico feito equivocadamente foi o de infecção, com cinco casos (26,7% dos discordantes, seguido por rejeição hiperaguda, com quatro casos (20% dos discordantes, e tromboembolismo pulmonar, com três casos (13,3% dos discordantes. Conclusão: Discordâncias entre o diagnóstico clínico e achados da necrópsia são comumente encontradas no transplante cardíaco. Novas estratégias no aperfeiçoamento do diagnóstico clínico devem ser introduzidas, considerando-se os resultados da necrópsia para melhoria do tratamento da insuficiência cardíaca por meio do transplante cardíaco.

  9. Hydrogen production with short contact time. Catalytic partial oxidation of hydrocarbons and oxygenated compounds: Recent advances in pilot- and bench-scale testing and process design

    Energy Technology Data Exchange (ETDEWEB)

    Guarinoni, A.; Ponzo, R.; Basini, L. [ENI Refining and Marketing Div., San Donato Milanese (Italy)

    2010-12-30

    ENI R and D has been active for fifteen years in the development of Short Contact Time - Catalytic Partial Oxidation (SCT-CPO) technologies for producing Hydrogen/Synthesis Gas. From the beginning the experimental work addressed either at defining the fundamental principles or the technical and economical potential of the technology. Good experimental responses, technical solutions' simplicity and flexibility, favourable techno-economical evaluations promoted the progressive widening of the field of the investigations. From Natural Gas (NG) the range of ''processable'' Hydrocarbons extended to Liquefied Petroleum Gas (LPG) and Gasoils, including those characterised by high levels of unsaturated and sulphurated molecules and, lately, to other compounds with biological origin. The extensive work led to the definition of different technological solutions, grouped as follows: Technology 1: Air Blown SCT-CPO of Gaseous Hydrocarbons and/or Light Compounds with biological origin Technology 2: Enriched Air/Oxygen Blown SCT-CPO of Gaseous Hydrocarbons and/or Light Compounds with biological origin Technology 3: Enriched Air/Oxygen Blown SCT-CPO of Liquid Hydrocarbons and/or Compounds with biological origin Recently, the licence rights on a non-exclusive basis for the commercialisation of SCT-CPO based processes for H{sub 2}/Synthesis gas production from light hydrocarbons with production capacity lower than 5,000 Nm{sup 3}/h of H{sub 2} or 7,500 Nm3/h of syngas have been assigned to two external companies. In parallel, development of medium- and large-scale plant solutions is progressing within the ENI group framework. These last activities are addressed to the utilisation of SCT-CPO for matching the variable Hydrogen demand in several contexts of oil refining operation. This paper will report on the current status of SCT-CPO with a focus on experimental results obtained, either at pilot- and bench- scale level. (orig.)

  10. Leptospirose de evolução fulminante: um caso de autópsia

    Directory of Open Access Journals (Sweden)

    Fernando Peixoto Ferraz de Campos

    2012-08-01

    Full Text Available A leptospirose é uma doença febril aguda septicêmica que afeta humanos e/ou animais com alta incidência mundial principalmente em países tropicais em desenvolvimento.É uma doença de ocorrência na zona rural e urbana com algumas características próprias ocupacionais ou recreativas. Os indivíduos mais acometidos na grande maioria das vezes são jovens ou adultos jovens. Aproximadamente 5% - 15% dospacientes apresentam a forma grave da doença conhecida como doença de Weill que pode se associar a síndrome da hemorragia pulmonar da leptospirose. Apresentamosum relato de autópsia de uma paciente octogenária, residente na zona urbana do município de São Paulo, internada no Hospital Universitário da Universidade de São Paulo, que apresentou quadro de evolução fulminante. A autópsia revelou comprometimento dos pulmões com hemorragia alveolar difusa e infiltração mononuclear dos septos alveolares. A histologia do fígado apresentava destrabeculação dos hepatócitos, alargamento dos sinusóides e hiperplasia das células de Kupfer. Necrose tubular aguda e nefrite intersticial caracterizaram a histologia dos rins.

  11. Hydrogen/Deuterium Exchange Reveals Distinct Agonist/Partial Agonist Receptor Dynamics within the intact Vitamin D Receptor/Retinoid X Receptor Heterodimer

    Science.gov (United States)

    Zhang, Jun; Chalmers, Michael J.; Stayrook, Keith R.; Burris, Lorri L.; Garcia-Ordonez, Ruben D.; Pascal, Bruce D.; Burris, Thomas P.; Dodge, Jeffery A.; Griffin, Patrick R.

    2010-01-01

    Summary Regulation of nuclear receptor (NR) activity is driven by alterations in the conformational dynamics of the receptor upon ligand binding. Previously we demonstrated that hydrogen/deuterium exchange (HDX) can be applied to determine novel mechanism of action of PPARγ ligands and in predicting tissue specificity of selective estrogen receptor modulators. Here we applied HDX to probe the conformational dynamics of the ligand binding domain (LBD) of the vitamin D receptor (VDR) upon binding its natural ligand 1α,25-dihydroxyvitamin D3 (1,25D3), and two analogs, alfacalcidol and ED-71. Comparison of HDX profiles from ligands in complex with the LBD with full-length receptor bound to its cognate receptor retinoid X receptor (RXR) revealed unique receptor dynamics that could not be inferred from static crystal structures. These results demonstrate that ligands modulate the dynamics of the heterodimer interface as well as providing insight into the role of AF-2 dynamics in the action of VDR partial agonists. PMID:20947021

  12. Autópsia oro-facial em vítimas de desastres em massa

    OpenAIRE

    Ventura, Cláudia Patrícia Moura

    2012-01-01

    Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária A Medicina Dentária Forense representa uma área da Medicina Dentária que visa extrair informações das peças e respetivos tecidos adjacentes e aplicar essas informações no processo de identificação humana. A medicina dentária forense utiliza métodos diferentes, entre eles salientamos a autópsia oro-facial que visa a extração dos ma...

  13. Toracocentese e biópsia pleural Thoracentesis and pleural biopsy

    Directory of Open Access Journals (Sweden)

    Roberta Sales

    2006-08-01

    Full Text Available A toracocentese é o método de escolha para a obtenção de amostras de líquido pleural. Embora seja considerado um procedimento pouco invasivo, é fundamental que a toracocentese obedeça a uma técnica padronizada com a finalidade de aprimorar a chance de diagnóstico e minimizar riscos. A biópsia de pleura tem por objetivo ampliar e complementar a chance de diagnóstico das doenças pleurais, sendo indicada em casos selecionados.Thoracentesis is the method of choice for obtaining samples of pleural fluid. Although it is considered a minimum invasive procedure, it is crucial to follow a standardized technique with the purpose of optimizing the chance of diagnosis and minimizing risks. The pleura biopsy may enlarge and complement the chance of diagnosis of the pleural diseases and is indicated in selected cases.

  14. Metal vapor condensation under high pressure (mercury vapor to 500 psia). [Heat transfer coefficients

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, S.; Bonilla, C.F.

    1975-01-01

    Mercury vapor up to 500 psia was condensed outside a cylindrical tube in both horizontal and vertical positions. Results show consistently low heat transfer coefficients compared to Nusselt's theory. Two auxiliary mercury vapor condensers downstream of the boiler vent were used to control and safeguard the system. Constantan wires were spot welded on the surface inside the test condenser tube. The heat flux ranged from 20,000 to 45,000 Btu/h-ft/sup 2/ and the temperature differences between vapor and condensing wall from 6 to 50/sup 0/F. The condensation heat transfer coefficients, ranging from 850 to 3,500 Btu/h-/sup 0/F-ft/sup 2/, are only about 3 to 9 percent of those predicted by Nusselt's theory. Due to the positive pressure in the system for most test runs, the chance of any in-leakage of noncondensable gases into the boiler is extremely small. Since no substantial change of heat transfer rate resulted from wide variations in the heat load on the reflux condenser at some specific heat flux on the test condenser tube, the low heat transfer rate of mercury vapor condensation was not due to the presence of any non-condensable gas. The test data for high vapor pressure up to 500 psia reveal that the heat transfer coefficient is independent of the vapor pressure level. The condensation coefficients calculated based on kinetic theory are much smaller than unity and decreasewith vapor pressure. It is hypothesized that dimer content in the metal vapor phase might behave as non-condensable or semi-condensable gas and create a diffusional barrier at the vapor-liquid interface near the condensate film. This dimer vapor could be the main cause of interfacial resistance during metal vapor condensation process. 41 figures, 7 tables, 58 references. (DLC)

  15. Toxic myopathies: muscle biopsy features Miopatia tóxica: biópsia muscular

    Directory of Open Access Journals (Sweden)

    Rosana Herminia Scola

    2007-03-01

    Full Text Available Several drugs and toxic substances can cause muscular abnormalities and are frequent causes of acquired myopathies. We present a series of 32 patients, predominance of young adult patients, diagnosed with toxic myopathy. The most common substances inducing myopathy were corticosteroids (56.2% followed by the propoxyphene, neuroleptics, zidovudine and drug-induced hypokalemia. The investigation showed normal serum creatine kinase levels in 65.4%, myopathic pattern of the needle electromyography in 40% and the more frequent histological diagnosis of the muscle biopsy was type 2 fiber atrophy (59.3%. Clinical features, etiology, course of the disease, serum levels of muscular enzymes, electromyographic features and, especially, muscle biopsy features are discussed.Diversos medicamentos e substâncias tóxicas podem causar alterações musculares e são causas freqüentes de miopatia adquirida. Apresentamos uma série de 32 pacientes, predomínio de pacientes adulto jovens, com miopatia tóxica. As substâncias mais relacionadas com a miopatia foram os corticosteróides (56,2% seguidos pelo propoxifeno, neurolépticos, zidovudina e drogas indutoras de hipocalemia. A investigação mostrou níveis normais de creatino quinase sérica em 65,4%, eletromiografia de agulha com padrão miopático em 40% e o mais freqüente diagnóstico histológico da biópsia muscular foi atrofia de fibras do tipo 2 (59,3%. As manifestações clínicas, etiologia, tempo de evolução, nível sérico das enzimas musculares, alterações da eletroneuromiografia e, especialmente, da biópsia muscular são discutidos.

  16. Molecular Mechanisms for the Modulation of Selected Inflammatory Markers by Dietary Rice Bran Oil in Rats Fed Partially Hydrogenated Vegetable Fat.

    Science.gov (United States)

    Rao, Y Poorna Chandra; Kumar, P Pavan; Lokesh, B R

    2016-04-01

    Industrially produced partially hydrogenated vegetable fat (PHVF) contains trans fatty acids (TFA) mostly comprising elaidic acid (EA, 18:1∆9t). Though, the harmful effects of TFA on health have been repeatedly publicized, the fat containing TFA have been continued to be used as a cooking medium in many regions of the world. The adverse effects of PHVF on oxidative stress and inflammatory markers and the possible ameliorative action of rice bran oil (RBO) on these markers were evaluated. Weaning rats were fed a AIN-93 purified diet supplemented with the following lipids: groundnut oil (GNO, 10 wt%), PHVF (10 wt%), RBO (10 wt%), PHVF blended with RBO at 2.5, 5.0 and 7.5 wt% levels. The final concentration of the lipids in the diet was maintained at 10 wt%. Rats were fed these diets for 60 days. They were sacrificed and analyzed for oxidative stress and inflammatory markers. The rats fed PHVF showed lower levels of lipid peroxidation and hepatic antioxidant enzymes. The rats fed PHVF-containing diets showed enhanced levels of interleukin-1β, C-reactive proteins and also showed enhanced levels of paw inflammation when injected with carrageenan as compared to rats given GNO, RBO or PHVF blended with incremental amounts of RBO. The macrophages from rats fed diet containing PHVF showed up-regulation in the expressions of cytosolic phospholipase A2 (cPLA2), nuclear factor-κB p65, toll like receptor (TLR)-2, TLR-4 and down-regulation in the expressions of peroxisome proliferator activated receptor gamma (PPAR)γ, adiponectin receptor (AdipoR)-1 and AdipoR-2 when compared to rats fed diet containing GNO, RBO and PHVF blended with RBO. It was concluded that dietary PHVF enhance pro-inflammatory markers which can be reduced by judiciously blending PHVF with RBO.

  17. Interesterified fat or palm oil as substitutes for partially hydrogenated fat in maternal diet can predispose obesity in adult male offspring.

    Science.gov (United States)

    Magri, Tatiana P R; Fernandes, Flávia S; Souza, Amanda S; Langhi, Larissa G P; Barboza, Thiago; Misan, Vanessa; Mucci, Daniela B; Santos, Raísa M; Nunes, Thaiza F; Souza, Sergio A L; de Mello Coelho, Valéria; Tavares do Carmo, Maria das Graças

    2015-10-01

    Palm oil (PO) and interesterified fat (IF) have been used to replace partially hydrogenated fat (PHF), which is rich in trans isomers, in processed foods. The purpose of this study was to investigate whether normolipidic diets containing PHF, IF, or PO consumed during pregnancy and lactation affect total body adiposity and adipose tissue morphology of adult offspring mice. Four groups of female C57BL/6 mice were fed, during pregnancy and lactation, a control diet (control group, CG), a PHF diet (trans group, TG), a PO diet (PG group), or an IF diet (IG group). After weaning (at 21 days), male pups received the control diet for 70 days. Food intake and body weight were monitored in all groups throughout the experimental period. At 3 months of age, mice were sacrificed and the inguinal (IWAT), epididymal (EWAT), retroperitoneal (RPWAT), and mesenteric (MWAT) adipose fat pads were removed and weighed. Adiposity was quantified by micro computed tomography (micro-CT), and adipocyte areas and cell number were analyzed by histology. PG and IG offspring gained more weight than CG and TG groups (p fat depots were greater in IG animals, as compared to the other groups. Larger adipocyte areas were observed in EWAT and IWAT in IG and TG, respectively, in comparison to CG and PG mice. PG mice showed increased adipocyte numbers in IWAT. Maternal intake of IF and/or PO during pregnancy and lactation predisposes the offspring to the development of obesity in adult life in mice. Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  18. Biópsia per-oral do intestino delgado em 150 casos de diferentes enteroparasitoses

    Directory of Open Access Journals (Sweden)

    Norton de Figueiredo

    1967-04-01

    Full Text Available Os autores fazem uma apresentação sumária de alguns tipos de instrumentos utilizados na realização da biópsia duodeno-jejunal através intubação oral, ao mesmo tempo que comentam a importância do método no estudo da patologia intestinal. Em seguida apresentam os resultados de sua experiência empregando 6 diferentes tipos de sondas e mostram os resultados histopatológicos observados em 150 casos de diversas parasitoses intestinais, submetidos a estudo. Entre os resultados chamam a atenção para a presença freqüente da Giardia lamblia, detectada em 16 dos 50 (32% casos desta parasitose, contra 3 dos 27 (11,1% de esquistossomose e apenas 2 dos 108 (1,8% de estrongiloidíase. Relatam também o achado de numerosas leishmânias no córion da mucosa jejunal de um paciente parasitado pela Giardia lamblia, que era portador de Calazar. Apreciam, ainda, o significado de outras alterações, consideradas inespecíficas, sobre as quais aguardam estudos mais completos, para chegar a conclusões mais válidas. Entre estas, merece destaque o achado de atrofia das vilosidades intestinais em 27 pacientes infectados pelo Strongyloides stercoialis tendo que em 5 dêles havia parasitismo exclusivo pelo referido nematóide.

  19. Retratos de autópsias Psicossociais sobre suicídio de idosos em Teresina

    Directory of Open Access Journals (Sweden)

    Selena Mesquita Teixeira Sérvio

    Full Text Available O desígnio da presente pesquisa consiste em analisar os fatores psicossociais que perpassaram o suicídio de idosos em Teresina, por meio de uma investigação retrospectiva dos aspectos da vida do suicida antes do autoextermínio e da reconstituição dos fatores de risco para o suicídio. Trata-se de uma pesquisa de natureza qualitativa, descritiva e exploratória. Foram construídas autópsias psicossociais de cinco casos de suicídios de idosos ocorridos no período de 2004 a 2009. Esse método reúne três tipos de informação: ficha de identificação pessoal e social, genograma e entrevista semi-estruturada. A coleta foi viabilizada pelo relato de cinco sujeitos, familiares e parentes próximos ao idoso. O material obtido passou por três etapas: pré-análise, análise qualitativa e síntese analítica. Desse modo, os principais fatores de risco associados ao suicídio desses idosos foram: depressão, transtornos mentais graves, estigma referente ao envelhecimento, alcoolismo, automutilações, impulsividade, relações afetivas fragilizadas e história de vida marcada por eventos trágicos.

  20. The microbiology behind the biogas process, stressing the regulating role of the hydrogen partial pressure. Mikrobiologien bag biogasprocessen med betoning av hydrogenpartialtrykkets regulerende rolle

    Energy Technology Data Exchange (ETDEWEB)

    Ahring, B. (Danmarks Tekniske Hoejskole, Lyngby (DK). Inst. for Bioteknologi); Westermann, P. (Copenhagen Univ. (DK). Dept. of General Microbiology)

    1989-01-01

    Anaerobic degradation of organic matter involves a complex mixture of bacteria - each with a specific role in the over-all degradation process. Three major metabolic groups of bacteria are involved: The hydrolytic and fermentative bacteria, which convert complex biopolymers, sugars, amino acids, fatty acids and so on to acetate, hydrogen and carbon dioxide on the one hand, and a mixture of alcohols, fatty acids, succinate, and lactate on the other. The latter substrates have to be converted to acetate, hydrogen, and carbon dioxide by the hydrogen-producing acetogenic bacteria, which depend for thermodynamic reasons on efficient removal of their fermentation product. The third group, the methanogenic bacteria, convert acetate, hydrogen, and carbon dioxide as well as the less important one carbon compounds methanol, methylamine, and formate to methane and carbon dioxide. The key regulator of anaerobic fermantations is hydrogen effectuated through interspecies hydrogen transfer. The special feature of this process is that hydrogen-using organisms can create conditions for obligate hydrogen-producing organisms to perform catabolic oxidations which would not have been energy-yielding in the absence of hydrogen removal. The last decade has brought some significant steps forward in our understanding of the anaerobic fermentation process. However, the influence of the ability of micro-organisms to use more than one energy substrate at a time, and to switch their catabolism from breaking carbon-carbon bonds to forming new carbon-carbon bonds, has only been studied to a small extent. Further, knowledge on the anaerobic degradation process is expected to evolve in the nearest future.

  1. Hydrogen rich gas generator

    Science.gov (United States)

    Houseman, J. (Inventor)

    1976-01-01

    A process and apparatus is described for producing a hydrogen rich gas by introducing a liquid hydrocarbon fuel in the form of a spray into a partial oxidation region and mixing with a mixture of steam and air that is preheated by indirect heat exchange with the formed hydrogen rich gas, igniting the hydrocarbon fuel spray mixed with the preheated mixture of steam and air within the partial oxidation region to form a hydrogen rich gas.

  2. Achados clínicopatológicos na tromboembolia pulmonar: estudo de 24 anos de autópsias

    OpenAIRE

    Bok Yoo,Hugo Hyung; Mendes,Fabiana Guandalini; Alem,Christine Elisabete Rubio; Fabro,Alexandre Todorovic; Corrente,José Eduardo; Queluz,Thais Thomaz

    2004-01-01

    INTRODUÇÃO: Tromboembolia pulmonar (TEP) é ainda uma afecção enigmática em diversos aspectos clínicos e epidemiológicos e frequentemente erroneamente diagnosticada. OBJETIVO: Descrever a prevalência e os achados anatomopatológicos de TEP em uma série de 5261 autópsias realizadas em um hospital universitário de nível terciário, correlacionar estes achados com as doenças de base e verificar a freqüência de suspeita clínica antemortem de TEP. MÉTODO: Revisão dos registros das autópsias consecuti...

  3. É a biópsia incisional útil na classificação dos carcinomas basocelulares?

    OpenAIRE

    Messina,Maria Cristina de Lorenzo; Valente,Neusa Yuriko Sakai; Castro,Luiz Guilherme Martins

    2006-01-01

    FUNDAMENTOS: O carcinoma basocelular é tumor constituído por diferentes tipos histológicos, que demonstram diversificado potencial de agressividade. Sabe-se que a correlação entre os tipos histológicos de carcinoma basocelular encontrados no material de biópsia pré-operatória e no material da peça cirúrgica excisional não é total. Na literatura essa correlação varia de 42,7 a 80%. OBJETIVO: Avaliar a correlação entre os tipos histológicos de carcinoma basocelular nas biópsias incisionais e re...

  4. Biópsia hepática por laparotomia paracostal em bovinos e búfalos

    OpenAIRE

    Minervino,Antonio Humberto Hamad; Barrêto Júnior,Raimundo Alves; Rodrigues,Frederico Augusto Mazzocca Lopes; Ferreira,Rodrigo Nogueira Fernandes; Saut,João Paulo Elsen; Queiroz,Genilson Fernandes; Reis,Leonardo Frasson dos; Ortolani,Enrico Lippi

    2009-01-01

    A técnica de biópsia hepática em ruminantes tem importante valor no diagnóstico clínico de doenças tóxicas e metabólicas, em especial nos desequilíbrios minerais. As técnicas mais comumente utilizadas restringem análises devido ao limitado volume de tecido obtido. No presente trabalho, avaliou-se o uso de uma técnica de biópsia hepática por laparotomia paracostal em bovinos e búfalos. Foram utilizados 10 bovinos e 10 búfalos hígidos. Os animais foram mantidos em estação, sedados com xilazina ...

  5. ASU nitrogen sweep gas in hydrogen separation membrane for production of HRSG duct burner fuel

    Science.gov (United States)

    Panuccio, Gregory J.; Raybold, Troy M.; Jamal, Agil; Drnevich, Raymond Francis

    2013-04-02

    The present invention relates to the use of low pressure N2 from an air separation unit (ASU) for use as a sweep gas in a hydrogen transport membrane (HTM) to increase syngas H2 recovery and make a near-atmospheric pressure (less than or equal to about 25 psia) fuel for supplemental firing in the heat recovery steam generator (HRSG) duct burner.

  6. Quantitative effects on cardiovascular risk factors and coronary heart disease risk of replacing partially hydrogenated vegetable oils with other fats and oils.

    Science.gov (United States)

    Mozaffarian, D; Clarke, R

    2009-05-01

    Reduced consumption of trans-fatty acids (TFA) is desirable to lower coronary heart disease (CHD) risk. In practice, partially hydrogenated vegetable oils (PHVO) that contain both TFAs and other fatty acids are the unit of replacement and could be replaced with diverse alternative fats and oils. We performed quantitative estimates of CHD effects if a person's PHVO consumption were to be replaced with alternative fats and oils based on (1) randomized dietary trials and (2) prospective observational studies. We performed meta-analyses of (1) the effects of TFAs on blood lipids and lipoproteins in controlled dietary trials and (2) associations of habitual TFA consumption with CHD outcomes in prospective cohort studies. On the basis of these results and corresponding findings for saturated fatty acids (SFA), cis-monounsaturated fatty acids (MUFA) and cis-polyunsaturated fatty acids (PUFA), we calculated the effects on CHD risk for replacing 7.5% of energy from three different PHVO formulations (containing 20, 35 or 45% TFAs) with butter, lard, palm or vegetable oils. In controlled trials, each 1% energy replacement of TFAs with SFAs, MUFAs or PUFAs, respectively, decreased the total cholesterol (TC)/high-density lipoprotein cholesterol (HDL-C) ratio by 0.31, 0.54 and 0.67; the apolipoprotein (Apo)-B/ApoAI ratio by 0.007, 0.010 and 0.011; and lipoprotein (Lp)(a) by 3.76, 1.39 and 1.11 mg/l (Pfats from one trial. On the basis of these risk factor changes in controlled trials, CHD risk would be variably decreased by different fats and oils replacing 7.5% of energy from 20% TFA PHVO (CHD risk reduction: -2.7% (butter) to -9.9% (canola)); 35% TFA PHVO (-11.9% (butter) to -16.0% (canola)); or 45% TFA PHVO (-17.6% (butter) to -19.8% (canola)). In prospective cohort studies, each 2% energy replacement of TFAs with SFAs, MUFAs or PUFAs would lower CHD risk by 17% (95% confidence interval (CI)=7-25%), 21% (95% CI=12-30%) or 24% (95% CI=15-33%), respectively. On the basis of

  7. Methanol partial oxidation reformer

    Science.gov (United States)

    Ahmed, Shabbir; Kumar, Romesh; Krumpelt, Michael

    1999-01-01

    A partial oxidation reformer comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell.

  8. Methanol partial oxidation reformer

    Science.gov (United States)

    Ahmed, S.; Kumar, R.; Krumpelt, M.

    1999-08-24

    A partial oxidation reformer is described comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell. 7 figs.

  9. Hydrogen Production by Catalytic Partial Oxidation of Coke Oven Gas in BaCo0.7Fe0.3-xZrxO3-δ Ceramic Membrane Reactors

    Directory of Open Access Journals (Sweden)

    Yao Weilin

    2016-01-01

    Full Text Available The BaCo0.7Fe0.3-xZrxO3-δ (BCFZ, x = 0.04–0.12 mixed ionic–electronic conducting (MIEC membranes were synthesized with a sol–gel method and evaluated as potential membrane reactor materials for the partial oxidation of coke oven gas (COG. The effect of zirconium content on the phase structure, microstructure and performance of the BCFZ membrane under He or COG atmosphere were systemically investigated. The BaCo0.7Fe0.24Zr0.06O3-δ membrane exhibited the best oxygen permeability and good operation stability, which could be a potential candidate of the membrane materials for hydrogen production through the partial oxidation of COG.

  10. Phase-equilibrium properties of coal-derived liquids. Technical progress report, January-July 1983. [70 to 700/sup 0/F; up to 2000 psia

    Energy Technology Data Exchange (ETDEWEB)

    Yesavage, V.F.; Kidnay, A.J.

    1983-07-01

    Thermodynamic property research is justly recognized as invaluable by process and design engineers in the petroleum, chemical, and allied industries. Thermodynamic data for pure fluids or complex mixtures are essential in the optimum design of both physical and chemical processing units. Coal-derived liquids are a new and vital class of industrial compounds for which there are limited thermodynamic data. Programs have been undertaken to measure volumetric properties and K values of light gas-model compound systems and to measure dew points, vapor pressures, and hydrogen solubilities in model compound and coal-derived liquid systems. The objective of the present study is to measure equilibrium K values of coal-derived liquids and model compounds representative of coal liquids, and to use the results in the development of engineering correlations. The program is divided into three major areas: design, construction, and evaluation of an equilibrium flash vaporization system for temperatures between 70 and 700/sup 0/F and pressures up to 2000 psia; measurements on samples of both coal-derived liquids and mixtures of model compounds; and preparation of engineering correlations for the measured K values and vapor liquid equilibria. Due to continued leaks of potentially harmful cresol and quinoline in the flash-vaporization cell it became necessary for us to shut down the equipment for reasons of safety. Efforts to seal the original cell over the large temperature cycles required proved ineffective. Thus, the major effort during the past six months was the design, construction, and development of a new equilibrium cell that would maintain the seal between the cell and the sight window over many temperature cycles. The final design which accomplishes this objective uses a custom-fabricated sapphire window with custom gold o-rings used for the seals. Due to the unanticipated equipment development, the data-collection effort has been delayed.

  11. Freqüência de Candida sp. em biópsias de lesões da mucosa bucal

    Directory of Open Access Journals (Sweden)

    Spolidorio Luís Carlos

    2003-01-01

    Full Text Available O objetivo desse trabalho foi determinar a freqüência da infecção por Candida sp. em biópsias de lesões da mucosa bucal, assim como associar a presença de Candida sp. com lesões malignas e lesões com vários graus de displasia. Foram utilizadas 832 biópsias da mucosa bucal, previamente incluídas em parafinas, cujos blocos foram obtidos dos arquivos da Disciplina de Patologia da Faculdade de Odontologia de Araraquara da UNESP, no período entre 1990-2001. Três cortes seqüenciais foram corados pelo ácido periódico de Schiff (PAS. Do total de biópsias 27,2% foram PAS positivas, dessas 83,25% eram provenientes de pacientes do sexo masculino. Houve associação positiva entre infecção com displasia epitelial leve, moderada, severa, carcinoma espinocelular e hiperqueratose (p < 0,05. Não houve associação entre hiperplasia fibrosa inflamatória, líquen plano, granuloma piogênico (p < 0,05 com infecções fúngicas. A língua foi o sítio mais acometido por infecções em relação a outros sítios (p < 0,05. A partir dos dados quantitativos, concluiu-se que houve correlação positiva de infecção por fungos, lesões displásicas e carcinoma, sendo mais freqüente no sexo masculino. Estes dados não permitem inferir se o fungo causa displasia epitelial e carcinoma, mas confirmam a maior presença de Candida nessas lesões.

  12. Autothermal hydrogen storage and delivery systems

    Science.gov (United States)

    Pez, Guido Peter [Allentown, PA; Cooper, Alan Charles [Macungie, PA; Scott, Aaron Raymond [Allentown, PA

    2011-08-23

    Processes are provided for the storage and release of hydrogen by means of dehydrogenation of hydrogen carrier compositions where at least part of the heat of dehydrogenation is provided by a hydrogen-reversible selective oxidation of the carrier. Autothermal generation of hydrogen is achieved wherein sufficient heat is provided to sustain the at least partial endothermic dehydrogenation of the carrier at reaction temperature. The at least partially dehydrogenated and at least partially selectively oxidized liquid carrier is regenerated in a catalytic hydrogenation process where apart from an incidental employment of process heat, gaseous hydrogen is the primary source of reversibly contained hydrogen and the necessary reaction energy.

  13. Biópsia mamária realizada pela técnica de biópsia helicoide: estudo experimental Breast biopsy performed by the helicoid biopsy technique: an experimental study

    Directory of Open Access Journals (Sweden)

    Eliel de Souza

    2010-12-01

    Full Text Available OBJETIVO: avaliar o desempenho da biópsia helicoide na realização de biópsias mamárias. MÉTODOS: foi selecionado aleatoriamente uma amostra composta de 30 pacientes portadoras de câncer de mama submetidas à mastectomia. Foram excluídas as mulheres portadoras de tumor que tivessem consistência pétrea, não-palpável, com manipulação cirúrgica prévia ou que contivesse líquido. Utilizando-se o kit de biópsia helicoide e um equipamento de core biopsy com cânula e agulha de 14 gauge, respectivamente, coletou-se um fragmento por equipamento em área sã e nos tumores, em cada peça cirúrgica, totalizando 120 fragmentos para estudo histológico. Para a análise dos dados, definiu-se um nível de confiança de 95% e utilizou-se o software SPSS, versão 13; o índice de concordância Kappa e o teste paramétrico t de Student. RESULTADOS: a média das idades das pacientes foi de 51,6 anos (±11,1 anos. A core biopsy apresentou sensibilidade de 93,3%, especificidade de 100% e acurácia de 96,7%, enquanto a biópsia helicoide teve sensibilidade de 96,7%, especificidade de 100% e acurácia de 98,3%. Na comparação entre a histologia dos tumores e dos fragmentos de biópsias, houve alto grau de concordância nos diagnósticos (Kappa igual a 0,9, com pPURPOSE: to assess the helicoid biopsy performance when carrying out breast biopsies. METHODS: thirty patients with breast cancer submitted to mastectomy were selected at random. Women with a tumor of petreous consistency, nonpalpable, submitted to previous surgical manipulation or containing fluid were excluded. The helicoid biopsy kit and a core biopsy device with a cannula and a 14-gauge-needle, respectively, were used to collect a fragment each from a healthy area and from the tumor of each surgical specimen, for a total of 120 fragments for histological study. Data were analyzed statistically by the parametric Student's t-test and by the Kappa concordance index at the 95% confidence level

  14. Hydrogen energy systems studies

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.M.; Kreutz, T.G.; Steinbugler, M. [Princeton Univ., NJ (United States)] [and others

    1996-10-01

    In this report the authors describe results from technical and economic assessments carried out during the past year with support from the USDOE Hydrogen R&D Program. (1) Assessment of technologies for small scale production of hydrogen from natural gas. Because of the cost and logistics of transporting and storing hydrogen, it may be preferable to produce hydrogen at the point of use from more readily available energy carriers such as natural gas or electricity. In this task the authors assess near term technologies for producing hydrogen from natural gas at small scale including steam reforming, partial oxidation and autothermal reforming. (2) Case study of developing a hydrogen vehicle refueling infrastructure in Southern California. Many analysts suggest that the first widespread use of hydrogen energy is likely to be in zero emission vehicles in Southern California. Several hundred thousand zero emission automobiles are projected for the Los Angeles Basin alone by 2010, if mandated levels are implemented. Assuming that hydrogen vehicles capture a significant fraction of this market, a large demand for hydrogen fuel could evolve over the next few decades. Refueling a large number of hydrogen vehicles poses significant challenges. In this task the authors assess near term options for producing and delivering gaseous hydrogen transportation fuel to users in Southern California including: (1) hydrogen produced from natural gas in a large, centralized steam reforming plant, and delivered to refueling stations via liquid hydrogen truck or small scale hydrogen gas pipeline, (2) hydrogen produced at the refueling station via small scale steam reforming of natural gas, (3) hydrogen produced via small scale electrolysis at the refueling station, and (4) hydrogen from low cost chemical industry sources (e.g. excess capacity in refineries which have recently upgraded their hydrogen production capacity, etc.).

  15. Influence of dietary partially hydrogenated fat high in trans fatty acids on lipid composition and function of intestinal brush border membrane in rats.

    Science.gov (United States)

    Ghafoorunissa, S A.I.

    2001-02-01

    The effect of dietary hydrogenated fat (Indian vanaspati) high in trans fatty acids (6 en%) on lipid composition, fluidity and function of rat intestinal brush border membrane was studied at 2 and 8 en% of linoleic acid. Three groups of weanling rats were fed rice-pulse based diet containing 10% fat over a ten week period: Group I (groundnut oil), Group II (vanaspati), Group III (vanaspati + safflower oil). The functionality of the brush border membrane was assessed by the activity of membrane bound enzymes and transport of D-glucose and L-leucine. The levels of total cholesterol and phospholipids were similar in all groups. The data on fatty acid composition of membrane phospholipids showed that, at 2 en% of linoleic acid in the diet, trans fatty acids lowered arachidonic acid and increased linoleic acid contents indicating altered polyunsaturated fatty acid metabolism. Alkaline phosphatase activity was increased while the activities of sucrase, gamma-glutamyl transpeptidase and transport of D-glucose and L-leucine were not altered by dietary trans fatty acids. However at higher intake of linoleic acid in the diet, trans fatty acids have no effect on polyunsaturated fatty acid composition and alkaline phosphatase activity of intestinal brush border membrane. These data suggest that feeding dietary fat high in trans fatty acids is associated with alteration in intestinal brush border membrane polyunsaturated fatty acid composition and alkaline phosphatase activity only when the dietary linoleic acid is low.

  16. Biópsia estereotáxica guiada por imagem nas lesões do sistema nervoso central

    Directory of Open Access Journals (Sweden)

    NASSER JOSÉ AUGUSTO

    1998-01-01

    Full Text Available Em 44 biópsias estereotáxicas, guiadas por imagem, no período de agosto-1995 até março-1997, as lesões encontradas foram (ordem de frequência: gliomas (glioblastoma multiforme o mais comum, linfoma primário e demais lesões ligadas à síndrome da imunodeficiência adquirida, metástases, vasculites, cisto aracnóideo, doença de Creutzfeldt-Jakob, nódulo fibroglial calcificado. A idade variou de 1 a 83 anos. 41 lesões eram supratentoriais, 2 infratentoriais e uma da calota craniana. A mortalidade foi nula e a morbidade 2,3%. A literatura é revista. O autores concluem que este procedimento é seguro e eficaz.

  17. A importância da biópsia muscular no diagnóstico de neuromiopatias

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Bleggi-Torres P

    1994-09-01

    Full Text Available As doenças neuromusculares têm quadro clínico variado e manifestam-se principalmente em pacientes jovens, determinando incapacidade funcional progressiva. Avaliação clínica, eletromiografia, bioquímica sangüínea e biópsia muscular são indispensáveis para o correto diagnóstico etiológico. Apresentamos casuística de 124 casos diagnosticados por biópsia muscular com histoquímica enzimática, microscopia eletrônica e avaliação morfométrica da variação no diâmetro das fibras afetadas, comentando os principais elementos diagnósticos anátomo-patológicos. Necrose muscular, grande variabilidade no diâmetro de fibras e infiltração adiposa muscular predominam nos quadros miopáticos distróficos, que representaram 26% de nossos casos. Redução volumétrica com angulação das fibras sugeriu origem neurogênica, sendo a alteração importante detectada em 27% de nossos diagnósticos. Miopatia mitocondrial caracteriza-se por acúmulos periféricos de grande quantidade de mitocôndrias com ultraestrutura alterada. Cuidados especiais na escolha e coleta da amostra muscular podem minimizar achados inespecíficos ou alterações tipo estádio terminal que impossibilitam a caracterização adequada da doença.

  18. Enthalpy measurement of coal-derived liquids. Final technical progress report. [200 to 740/sup 0/F and 200 to 1500 psia

    Energy Technology Data Exchange (ETDEWEB)

    Kidnay, A.J.; Yesavage, V.F.

    1981-05-01

    This final report presents the results of the enthalpy measurements on the model compound m-cresol. The measurements cover the temperature range 200 to 740/sup 0/F and the pressure range 200 to 1500 psia. These data are compared with earlier data taken on m-cresol and with other thermophysical properties taken from the literature.

  19. Tumores do tronco cerebral: estudo anatomopatológico em 35 casos de necrópsia

    Directory of Open Access Journals (Sweden)

    Carmen Lúcia Penteado Lancellotti

    1989-09-01

    Full Text Available Os tumores do tronco cerebral são raros e geralmente tratados sem diagnóstico histopatológico. Sua incidência varia na literatura entre 1,09% e 17,5% dos tumores cerebrais. O objetivo do trabalho foi relatar a casuísti desses tumores em 28500 necrópsias realizadas de 1952 a 1985 no Departamento de Anatomia Patológica da Santa Casa de São Paulo. Enfatizamos os aspectos neuropatológicos, comparamos nossos casos com os de outras séries e salientamos os tumores mais observados nessa região, com a finalidade de procurar contribuir para melhor abordagem terapêutica. Utilizamos alguns dados clínicos e, através do exame anatomopatológico, localizamos o tumor no tronco cerebral sendo o diagnóstico microscópico estabelecido segundo os critérios da Organização Mundial da Saúde. Dos 428 tumores intracranianos observados, 35 estavam localizados no tronco cerebral. Foram aqui incluídos os tumores próprios do tronco cerebral e as metástases e excluídos os tumores que infiltravam o tronco. A maior incidência ocorreu na primeira década e a causa de óbito predominante foi edema cerebral. A localização preferencial foi a ponte e o tumor mais freqüente foi o glioblas-tomia multiforme (19 casos. As metástases ficaram em segundo lugar na freqüência (9 casos, na maioria dos casos de origem pulmonar. Apesar de alguns autores se posicionarem contra a biópsia de tumor nessa região, baseando-se no alto risco cirúrgico, discordamos dessa opinião, pois acreditamos que, frente ao diagnóstico de glioma, será importante a caracterização ou não de malignidade. Ainda, não devemos deixar de considerar os diagnósticos diferenciais de processo expansivo no tronco. Enfim, com o diagnóstico anatomopatológico de glioma ou de uma das possibilidades aventadas, o procedimento terapêutico poderá ser mais adequado.

  20. Muscle biopsy in Pompe disease Biópsia muscular na doença de Pompe

    Directory of Open Access Journals (Sweden)

    Lineu Cesar Werneck

    2013-05-01

    Full Text Available Pompe disease (PD can be diagnosed by measuring alpha-glucosidase levels or by identifying mutations in the gene enzyme. Muscle biopsies can aid diagnosis in doubtful cases. Methods: A review of muscle biopsy from 19 cases of PD (infantile, 6 cases; childhood, 4 cases; and juvenile/adult, 9 cases. Results: Vacuoles with or without glycogen storage were found in 18 cases. All cases had increased acid phosphatase activity. The vacuole frequency varied (almost all fibers in the infantile form to only a few in the juvenile/adult form. Atrophy of type 1 and 2 fibers was frequent in all forms. Atrophic angular fibers in the NADH-tetrazolium reductase and nonspecific esterase activity were observed in 4/9 of the juvenile/adult cases. Conclusion: Increased acid phosphatase activity and vacuoles were the primary findings. Most vacuoles were filled with glycogen, and the adult form of the disease had fewer fibers with vacuoles than the infantile or childhood forms.O diagnóstico da doença de Pompe (PD pode ser feito pela dosagem da enzima alfa-glicosidase ou pela mutação do seu gene codificador. A biópsia muscular pode ajudar em casos duvidosos. Métodos: Revisão das biópsias musculares de 19 casos de PD (forma infantil, 6 casos; infantil tardia, 4; e juvenil/adulto, 9. Resultados: Encontrados vacúolos em 18 casos, com ou sem depósito de glicogênio. Todos mostraram aumento da fosfatase ácida. Os vacúolos estavam presentes na maioria das fibras nas formas infantis, menos frequentes nas formas juvenil e mais raros nas formas do adulto. A atrofia de fibras dos tipos 1 e 2 ocorreram em todas as formas. Fibras atróficas na NADH-tetrazolium redutase e esterase não específica foram observadas em 4/9 das formas infantil tardia/adulta. Conclusões: Os dados mais frequentes foram vacúolos, preenchidos por glicogênio com atividade aumentada da fosfatase ácida. A forma adulta apresenta menor número de vacúolos que as formas infantil e infantil

  1. Doenças renais em pacientes idosos submetidos à biópsia percutânea de rins nativos

    Directory of Open Access Journals (Sweden)

    Claudine Maria Jorge de Oliveira

    2010-12-01

    Full Text Available INTRODUÇÃO: Tem ocorrido aumento da população de idosos e estes vêm envelhecendo em melhores condições clínicas do que no passado. Entretanto, a distribuição e evolução das doenças renais nos idosos ainda são pouco conhecidas, em parte devido à resistência em indicar biópsia renal. OBJETIVO: Avaliar a distribuição, a evolução e as características clínicas das nefropatias diagnosticadas por biópsia em pacientes idosos. PACIENTES E MÉTODOS: Foram avaliadas todas as biópsias renais percutâneas de rins nativos. Elas foram realizadas entre janeiro de 1990 e dezembro de 2006 em 71 pacientes com idade mínima de 60 anos (67,3 ± 6,5 anos, sendo 47 do gênero masculino e 24 do feminino. Os pacientes foram agrupados conforme a indicação clínica da biópsia. RESULTADOS: Síndrome nefrótica foi verificada em 35 pacientes (49,3% associada, na maioria dos casos, à nefropatia membranosa (17 casos, seguida por amiloidose e glomeruloesclerose segmentar e focal com 7 casos cada. Hipótese diagnóstica de injúria renal aguda (IRA, com 19 pacientes, teve como principais diagnósticos a necrose tubular aguda (6 casos e a nefropatia do cilindro (3 casos. Dentre os 19 casos, apenas dois tiveram evolução satisfatória, enquanto os demais morreram precocemente ou evoluíram para doença renal avançada. Doze pacientes biopsiados por hematúria ou proteinúria assintomática tiveram diagnósticos variados, mas a maioria já apresentava nefropatia crônica relevante. Biópsia por síndrome nefrítica ocorreu em 5 casos, também com diagnósticos variados. CONCLUSÕES: Síndrome nefrótica foi a principal indicação de biópsia renal com a nefropatia membranosa como diagnóstico mais frequente. Entre os pacientes com IRA e hematúria ou proteinúria assintomática os diagnósticos foram variados com elevadas taxas de nefropatia crônica avançada.

  2. Discrepâncias clínico-patológicas e achados cardiovasculares em 409 autópsias consecutivas

    Directory of Open Access Journals (Sweden)

    Aline Fusco Fares

    2011-12-01

    Full Text Available FUNDAMENTO: As discrepâncias entre os diagnósticos clínicos e em autópsia persistem em todo o mundo. OBJETIVO: Avaliamos as autópsias em um hospital-escola para analisar a precisão dos diagnósticos cardiovasculares clínicos em comparação aos achados post-mortem. MÉTODOS: As 409 autópsias consecutivas entre 2003 e 2006 foram analisadas em um hospital terciário de São José do Rio Preto, São Paulo (SP, Brasil. A comparação dos achados cardiovasculares clínicos e patológicos foi realizada por meio da classificação de discrepâncias de Goldman. RESULTADOS: A taxa de autópsia no hospital foi de 8%. As causas cardiovasculares de óbito representavam 42,8% (175 de 409 pacientes dos diagnósticos de autópsia. Em 98 pacientes (56%, houve discrepâncias significativas (classes I e II, o que representa uma grande proporção de diagnósticos equivocados de infarto mesentérico (84,6%, infarto agudo do miocárdio (64,7%, dissecção da aorta (64,2% e embolia pulmonar (62,5%. Foram observadas maiores taxas de concordância para a insuficiência cardíaca congestiva (59% e para o acidente vascular cerebral isquêmico agudo (58,8%. A idade, o sexo, o tempo de permanência e a última unidade de admissão no hospital não foram associados aos critérios de Goldman. CONCLUSÃO: As discrepâncias dos diagnósticos clínicos e em autópsia relativos à morte cardiovascular permanecem elevados no Brasil, a despeito dos recursos tecnológicos disponíveis. Além disso, nossos achados reforçam a importância do exame post-mortem como uma contribuição para a melhoria da assistência médica.

  3. Making the case for direct hydrogen storage in fuel cell vehicles

    Energy Technology Data Exchange (ETDEWEB)

    James, B.D.; Thomas, C.E.; Baum, G.N.; Lomas, F.D. Jr.; Kuhn, I.F. Jr. [Directed Technologies, Inc., Arlington, VA (United States)

    1997-12-31

    Three obstacles to the introduction of direct hydrogen fuel cell vehicles are often states: (1) inadequate onboard hydrogen storage leading to limited vehicle range; (2) lack of an hydrogen infrastructure, and (3) cost of the entire fuel cell system. This paper will address the first point with analysis of the problem/proposed solutions for the remaining two obstacles addressed in other papers. Results of a recent study conducted by Directed Technologies Inc. will be briefly presented. The study, as part of Ford Motor Company/DOE PEM Fuel Cell Program, examines multiple pure hydrogen onboard storage systems on the basis of weight, volume, cost, and complexity. Compressed gas, liquid, carbon adsorption, and metal hydride storage are all examined with compressed hydrogen storage at 5,000 psia being judged the lowest-risk, highest benefit, near-term option. These results are combined with recent fuel cell vehicle drive cycle simulations to estimate the onboard hydrogen storage requirement for full vehicle range (380 miles on the combined Federal driving schedule). The results indicate that a PNGV-like vehicle using powertrain weights and performance realistically available by the 2004 PNGV target data can achieve approximate fuel economy equivalent to 100 mpg on gasoline (100 mpg{sub eq}) and requires storage of approximately 3.6 kg hydrogen for full vehicle storage quantity allows 5,000 psia onboard storage without altering the vehicle exterior lines or appreciably encroaching on the passenger or trunk compartments.

  4. Partial priapism

    DEFF Research Database (Denmark)

    Hoyerup, Peter; Azawi, Nessn Htum

    2013-01-01

    With only 34 prior cases in world literature, partial priapism (PP), also called partial segmental thrombosis of the corpus cavernosum, is a rare urological condition. The aetiology and treatment of PP is still unclear, but bicycle riding, trauma, drug usage, sexual intercourse, haematological...

  5. Informatització i digitalització de casos de necròpsia reals com a base de l'autoaprenentatge en patologia veterinària

    OpenAIRE

    Marco Valle, Alberto

    2008-01-01

    Es descriu breument el procediment pel qual a partir dels casos de necròpsia remesos a un servei de diagnòstic públic de patologia veterinària es programa: 1. Un mòdul de pràctiques de necròpsia amb casos reals. 2. Docència d'autoaprenentatge mitjançant l'elaboració de treballs clinicopatològics basats en «casos reals». 3. Seminaris d'exposició i discussió pública dels casos d'autoaprenentatge presentats pels mateixos estudiants. 4. Creació i manteniment d'una col·lecció dipòsit d'imatges dig...

  6. Alterações da pressão arterial em pacientes submetidos à biópsia na cavidade oral

    OpenAIRE

    Lima, Francisco Jadson; Evangelista, Augusto Pierry de Araújo; Silva, Renata Tôrres Moreira da; Alves, Pollianna Muniz; Lins, Ruthineia Diógenes Alves Uchoa; Godoy, Gustavo Pina

    2016-01-01

    A biópsia é um procedimento simples realizado rotineiramente por cirurgiões-dentistas e médicos, porém gera grande ansiedade e medo nos pacientes envolvidos. O objetivo deste estudo foi analisar a prevalência de alterações na pressão arterial em 63 pacientes submetidos à biópsia da cavidade oral, no período compreendido entre os meses de outubro de 2008 a novembro de 2009. A monitoração da pressão arterial destes pacientes foi realizada através da utilização do esfigmomanômetro durante o exam...

  7. Enthalpy measurement of coal-derived liquids. Quarterly technical progress report, July-September, 1978. [148 to 459/sup 0/F; 100 to 300 psia

    Energy Technology Data Exchange (ETDEWEB)

    Kidnay, A.J.; Yesavage, V.F.

    1978-12-01

    Experimental measurements were completed on a naphtha sample (1046) furnished by the Pittsburg and Midway Coal Mining Company. A total of 38 measurements were made in the temperature region 148 to 459/sup 0/F, and at pressures of 100 and 300 psia. Additional analytical work was also completed on the SRC-I naphtha whose enthalpy measurements were reported in previous progress reports. Comparisons are given between the experimental SRC-I naphtha enthalpies and the available petroleum enthalpy correlations.

  8. Onboard hydrogen generation for automobiles

    Science.gov (United States)

    Houseman, J.; Cerini, D. J.

    1976-01-01

    Problems concerning the use of hydrogen as a fuel for motor vehicles are related to the storage of the hydrogen onboard a vehicle. The feasibility is investigated to use an approach based on onboard hydrogen generation as a means to avoid these storage difficulties. Two major chemical processes can be used to produce hydrogen from liquid hydrocarbons and methanol. In steam reforming, the fuel reacts with water on a catalytic surface to produce a mixture of hydrogen and carbon monoxide. In partial oxidation, the fuel reacts with air, either on a catalytic surface or in a flame front, to yield a mixture of hydrogen and carbon monoxide. There are many trade-offs in onboard hydrogen generation, both in the choice of fuels as well as in the choice of a chemical process. Attention is given to these alternatives, the results of some experimental work in this area, and the combustion of various hydrogen-rich gases in an internal combustion engine.

  9. Characterization of the {beta}-phase of the palladium-hydrogen equation of state

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, K.J.

    1998-07-01

    The {beta}-phase of the P-C-T curves of the palladium-hydrogen system is encountered at high pressures of gaseous hydrogen and low temperatures of this system. The {beta}-phase is characterized by an increase in the concentration of hydrogen in the palladium lattice with an increase in pressure of the free hydrogen gas surrounding the palladium. The P-C-T curves in this study are determined by gravimetric measurements of the hydrided palladium sample to determine the amount of hydrogen within the palladium lattice. The amount of hydrogen is kept constant within the experimental system and the temperature is varied which changes the pressures. The objective of this experimental thesis is to accurately determine the P-C-T curves of palladium in the {beta}-phase region to pressures of 20,000 psia and medium to low temperature region of {minus}60 C to 100 C.

  10. Impacts analysis regarding partially hydrogenated oils

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Ellen D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Turhollow, Jr., Anthony F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Zimmerman, Gregory P.. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Eaton, Laurence M [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bast, Cheryl B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-06-01

    The U.S. Food and Drug Administration (FDA) has the responsibility under the Federal Food, Drug, and Cosmetic Act (FD&C Act) [21 United States Code (U.S.C.) 301 et seq.] for assuring that the U.S. food supply is safe, sanitary, wholesome, and honestly labeled. Toward that end, FDA exercised approval authority over substances permitted for use as food additives. Substances that are generally recognized as safe (GRAS) are not subject to regulation as food additives under the FD&C Act.

  11. Hydrogen energy systems studies

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.M.; Steinbugler, M.; Dennis, E. [Princeton Univ., NJ (United States)] [and others

    1995-09-01

    For several years, researchers at Princeton University`s Center for Energy and Environmental Studies have carried out technical and economic assessments of hydrogen energy systems. Initially, we focussed on the long term potential of renewable hydrogen. More recently we have explored how a transition to renewable hydrogen might begin. The goal of our current work is to identify promising strategies leading from near term hydrogen markets and technologies toward eventual large scale use of renewable hydrogen as an energy carrier. Our approach has been to assess the entire hydrogen energy system from production through end-use considering technical performance, economics, infrastructure and environmental issues. This work is part of the systems analysis activity of the DOE Hydrogen Program. In this paper we first summarize the results of three tasks which were completed during the past year under NREL Contract No. XR-11265-2: in Task 1, we carried out assessments of near term options for supplying hydrogen transportation fuel from natural gas; in Task 2, we assessed the feasibility of using the existing natural gas system with hydrogen and hydrogen blends; and in Task 3, we carried out a study of PEM fuel cells for residential cogeneration applications, a market which might have less stringent cost requirements than transportation. We then give preliminary results for two other tasks which are ongoing under DOE Contract No. DE-FG04-94AL85803: In Task 1 we are assessing the technical options for low cost small scale production of hydrogen from natural gas, considering (a) steam reforming, (b) partial oxidation and (c) autothermal reforming, and in Task 2 we are assessing potential markets for hydrogen in Southern California.

  12. Enthalpy measurement of coal-derived liquids. Quarterly technical progress report, April--June 1978. [SRC process distillate; 157 to 675/sup 0/C and 130 to 1000 psia

    Energy Technology Data Exchange (ETDEWEB)

    Kidnay, A.J.; Yesavage, V.F.

    1978-08-01

    Experimental measurements were completed on a middle distillate furnished by Pittsburg and Midway Coal Mining Company. A total of 52 enthalpy measurements were made covering the ranges 157 to 675/sup 0/F and 130 to 1000 psia.

  13. Virtual autopsy in forensic sciences and its applications in the forensic odontology = A autópsia virtual nas ciências forenses e sua aplicação na Odontologia forense

    Directory of Open Access Journals (Sweden)

    Rosário Junior, Ademir Franco do

    2012-01-01

    Full Text Available Atualmente os avanços tecnológicos se fazem cada vez mais importantes nas ciências forenses. Por outro lado a autópsia ainda é uma abordagem tradicional na prática médica-odontológica, na qual evidências são coletadas por meio fotográfico e radiológico. Neste contexto, a Autópsia Virtual surge como uma ferramenta útil e complementar para o exame cadavérico. Através da alta tecnologia radiológica a Autópsia Virtual fornece uma visão eficiente e precisa do caso a ser analisado. Esta revisão crítica tem o objetivo de atualizar os Cirurgiões-dentistas apresentando o primeiro trabalho com o conteúdo voltado a Autópsia Virtual

  14. Down-regulation of NF-κB expression by n-3 fatty acid-rich linseed oil is modulated by PPARγ activation, eicosanoid cascade and secretion of cytokines by macrophages in rats fed partially hydrogenated vegetable fat.

    Science.gov (United States)

    Rao, Y Poorna Chandra; Lokesh, B R

    2017-04-01

    The industrially produced partially hydrogenated vegetable fat (PHVF) contains trans fatty acid mostly comprising of elaidic acid (18:1 ∆9t). PHVF is used as a cooking medium in Southeast Asian countries. The purpose of this study is to evaluate the effects of dietary PHVF on inflammatory mediators and possible ameliorative effects of n-3 fatty acid (α-linolenic acid, ALA)-rich linseed oil (LSO) on the inflammatory mediators. Male Wistar weaning rats were fed AIN-93-purified diet supplemented with one of the following lipids for 60 days, groundnut oil (GNO, 10 wt%), PHVF (10 wt%), LSO (10 wt%), PHVF blended with LSO at 2.5, 5.0 and 7.5 wt% levels. The final fat level in the diet was maintained at 10 wt%. The macrophages from rats fed PHVF showed higher levels of total cholesterol and free cholesterol as compared to those from rats fed GNO and LSO. Macrophages from rats fed PHVF down-regulated the expression of PPARγ and up-regulated the expressions of cytosolic phospholipase A2, cyclooxygenase-2, 5-lipoxygenase and nuclear factor-kappa B p65. The macrophages from rats fed PHVF secreted higher levels of pro-inflammatory eicosanoids and cytokines. The rats fed PHVF blended with LSO at incremental amounts showed a significant reduction in the expressions of pro-inflammatory markers in dose-dependent manner. Detrimental effects of dietary PHVF in enhancing pro-inflammatory agents in rats could be significantly reduced by providing ALA (n-3 PUFA)-rich LSO.

  15. Interesterified fat or palm oil as substitutes for partially hydrogenated fat during the perinatal period produces changes in the brain fatty acids profile and increases leukocyte-endothelial interactions in the cerebral microcirculation from the male offspring in adult life.

    Science.gov (United States)

    Misan, Vanessa; Estato, Vanessa; de Velasco, Patricia Coelho; Spreafico, Flavia Brasil; Magri, Tatiana; Dos Santos, Raísa Magno de Araújo Ramos; Fragoso, Thaiza; Souza, Amanda S; Boldarine, Valter Tadeu; Bonomo, Isabela T; Sardinha, Fátima L C; Oyama, Lila M; Tibiriçá, Eduardo; Tavares do Carmo, Maria das Graças

    2015-08-07

    We investigated whether maternal intake of normolipidic diets with distinct fatty acid (FA) compositions alters the lipidic profile and influences the inflammatory status of the adult offsprings׳ brains. C57BL/6 female mice during pregnancy and lactation received diets containing either soybean oil (CG), partially hydrogenated vegetable fat rich in trans-fatty acids (TG), palm oil (PG), or interesterified fat (IG). After weaning, male offspring from all groups received control diet. The FA profile was measured in the offspring׳s brains at post-natal days 21 and 90. Brain functional capillary density as well as leukocyte-endothelial interactions in the cerebral post-capillary venules was assessed by intravital fluorescence microscopy at post-natal day 90. Inflammation signaling was evaluated through toll-like receptor 4 (TLR4) content in brain of the adult offspring. In the 21-day old offspring, the brains of the TG showed higher levels of trans FA and reduced levels of linoleic acid (LA) and total n-6 polyunsaturated fatty acids (PUFA). At post-natal day 90, TG and IG groups showed reduced levels of eicosapentaenoic acid (EPA) and total n-3 PUFA tended to be lower compared to CG. The offspring׳s brains exhibited an altered microcirculation with increased leukocyte rolling in groups TG, PG and IG and in TG group increased leukocyte adhesion. The TLR4 content of TG, IG and PG groups only tended to increase (23%; 20% and 35%, respectively). Maternal consumption of trans FA, palm oil or interesterified fat during pregnancy and lactation can trigger the initial steps of inflammatory pathways in the brain of offspring in adulthood. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Hydrogen sensor

    Science.gov (United States)

    Duan, Yixiang; Jia, Quanxi; Cao, Wenqing

    2010-11-23

    A hydrogen sensor for detecting/quantitating hydrogen and hydrogen isotopes includes a sampling line and a microplasma generator that excites hydrogen from a gas sample and produces light emission from excited hydrogen. A power supply provides power to the microplasma generator, and a spectrometer generates an emission spectrum from the light emission. A programmable computer is adapted for determining whether or not the gas sample includes hydrogen, and for quantitating the amount of hydrogen and/or hydrogen isotopes are present in the gas sample.

  17. Será a insuficiência renal uma contra-indicação relativa para as biópsias broncoscópicas?

    Directory of Open Access Journals (Sweden)

    Nethal I. Metha

    2005-07-01

    Full Text Available Resumo: Em 1977, Cunningham e col. demonstraram que, nos doentes urémicos sujeitos a broncofibroscopia com biopsias, 45% tiveram hemorragias.Actualmente, não há trabalhos publicados que avaliem este risco.Os autores resolveram avaliar os processos de todas as broncofibroscopias realizadas entre 1997 e 2002 no Hospital de Bellvue, Nova Iorque, registando os resultados da ureia, da creatinina, do hemograma, do estudo da coagulação, do tipo de biópsias executadas da pré-medicação e das complicações.Os doentes eram incluídos nos trabalhos desde que tivessem a ureia superior ou igual a 30 mg/dl e/ou a creatinina superior ou igual a 2,0 mg/dl. Perante estes critérios foram incluídos no estudo 72 doentes.Vinte e cinco doentes dos 72(35 % foram submetidos a biopsias. Sete dos 25 (28 % foram hemodializados e 18 dos 25(72 % não foram hemodializados. Todos os doentes hemodializados foram submetidos à broncofibroscopia 24 horas depois da hemodiálise e foram submetidos a uma perfusão de desmopressina pré-broncofibroscopia, e um doente com coagulopatia recebeu plaquetas e plasma fresco.Os doentes hemodializados submetidos a biópsias tinham valores de ureia que oscilavam entre 31-65 mg/ /dl e valores de creatinina que oscilavam entre 5,2-18,7 mg/dl, e o único doente deste grupo que fez punção aspirativa transbrônquica tinha uma ureia de 32 mg/dl e uma creatinina de 4,3 mg/dl.Em doze dos 18 doentes não submetidos a hemodiálise e submetidos a biópsias, os valores de ureia oscilavam entre 20-69 mg/dl e os valores de creatinina entre 0,9-2,5 mg/dl. Deste grupo, os quatro doentes que foram submetidos a punção aspirativa transbrônquica tinham valores de ureia entre 20-62 mg/dl e valores de creatinina entre 1,1-4,5 mg/dl. Os dois doentes sujeitos a biópsias e punção aspirativa transbrônquica tinham valores de ureia de 30 e 35 mg/dl e valores de de 1,4 e 1,5 mg/dl. Um dos 25 doentes não hemodializados teve uma complica

  18. Morbidade da biópsia da próstata transretal guiada por ultrassonografia Morbidity of transrectal ultrasound guided prostate biopsy

    Directory of Open Access Journals (Sweden)

    Raphael Sandes Solha

    2013-04-01

    Full Text Available OBJETIVO: Avaliar a incidência de complicações pós-procedimento nos pacientes submetidos a biópsia prostática transretal guiada por ultrassom no setor de intervenção do Departamento de Diagnóstico por Imagem da Escola Paulista de Medicina - Universidade Federal de São Paulo. MATERIAIS E MÉTODOS: Foram avaliados, via contato telefônico, 132 pacientes submetidos a biópsia de próstata transretal guiada por ultrassom no período de abril/2011 a junho/2011, seguindo o protocolo padrão do nosso setor. RESULTADOS: As complicações pós-biópsia foram categorizadas em maiores e menores de acordo com a necessidade de avaliação médica adicional. Cinquenta e nove pacientes (61,8% apresentaram complicações, e desses, grande parte (86,4% apresentou sintomas leves e autolimitados, considerados menores. Oito pacientes (8,2% apresentaram complicações maiores, sendo que apenas um deles necessitou de tratamento sob regime de internação hospitalar. A retenção urinária foi a complicação maior mais incidente no nosso estudo. CONCLUSÃO: Corroborando outros estudos da literatura, nosso trabalho demonstrou baixa prevalência de complicações maiores após a biópsia prostática transretal.OBJECTIVE: To evaluate the incidence of postprocedural complications in patients submitted to transrectal ultrasound-guided prostate biopsy at the Unit of Intervention, Department of Imaging Diagnosis of Escola Paulista de Medicina - Universidade Federal de São Paulo. MATERIALS AND METHODS: Telephone interviews were conducted with 132 patients who had undergone transrectal ultrasound-guided prostate biopsy in the period from April 2011 to June 2011, according to the institution's protocol. RESULTS: Post-biopsy complications were categorized into two groups - minor and major complications, according to their need for further clinical evaluation. Complications were reported by 59 patients (61.8%, most of them (86.4% with mild and self-limited symptoms

  19. Enthalpy measurement of coal-derived liquids. Quarterly technical progress report, July--September 1978. [148 to 459/sup 0/F and 100 to 300 psia

    Energy Technology Data Exchange (ETDEWEB)

    Kidnay, A.J.; Yesavage, V.F.

    1978-12-01

    Experimental measurements were completed on a naphtha sample (1046) furnished by the Pittsburgh and Midway Coal Mining Company. A total of 38 measurements were made in the temperature region 148 to 459/sup 0/F, and at pressures of 100 and 300 psia. Additional analytical work was completed on the SRC-I naphtha whose enthalpy measurements were reported previously. Comparisons are given between the experimental SRC-I naphtha enthalpies and the available enthalpy data on petroleum fractions, including Kesler and Lee's correlation of these data. (LTN)

  20. New tritium and deuterium measurements in atmospheric hydrogen

    OpenAIRE

    Gonsior, Bernhard; Friedman, Irving; Lindenmayr, Georg

    2011-01-01

    Tritium and deuterium analysis were made on samples of atmospheric hydrogen collected in 1961. A positive correlation exists between tritium and deuterium. The heaviest samples yield a value of about +18% S.M.O.W. for atmospheric hydrogen. The deuterium concentration of the industrial hydrogen varies from ?18% to ?22%. The industrial hydrogen is partially ascribed to hydrogen from automobile exhaust gas. The corrected tritium concentration in atmospheric hydrogen continues to increase, doubl...

  1. Partial gigantism

    Directory of Open Access Journals (Sweden)

    М.М. Karimova

    2017-05-01

    Full Text Available A girl with partial gigantism (the increased I and II fingers of the left foot is being examined. This condition is a rare and unresolved problem, as the definite reason of its development is not determined. Wait-and-see strategy is recommended, as well as correcting operations after closing of growth zones, and forming of data pool for generalization and development of schemes of drug and radial therapeutic methods.

  2. Hydrogen Generator

    Science.gov (United States)

    1983-01-01

    A unit for producing hydrogen on site is used by a New Jersey Electric Company. The hydrogen is used as a coolant for the station's large generator; on-site production eliminates the need for weekly hydrogen deliveries. High purity hydrogen is generated by water electrolysis. The electrolyte is solid plastic and the control system is electronic. The technology was originally developed for the Gemini spacecraft.

  3. Estudo ultrastrutural de biópsias de conjuntiva em doenças metabólicas do sistema nervoso

    Directory of Open Access Journals (Sweden)

    S. Rosemberg

    1987-03-01

    Full Text Available Quarenta biópsias de conjuntivas obtidas de um número igual de crianças portadoras de doenças metabólicas do SNC, ou supostas de tal acometimento, foram analisadas do ponto de vista ultrastrutural. Em 20 casos foram observadas alterações ultrastruturais que possibilitaram firmar o diagnóstico de muco-polissacaridose em 8, gangliosidose G M1 em 6, distrofia neuro-axonal infantil em 4, gangliosidose G M1 em um e forma infantil tardia de lipofuscinose ceróide em um. Nos 20 casos em que o exame revelou-se negativo, este era esperado em dois (doença de Leigh e de Hallervorden-Spatz; em dois, o resultado revelou-se falso negativo (leucodistrofia metacromática e adrenoleucodistrofia; em 12 casos sua negatividade permitiu afastar doença de acúmulo; em 4 casos suspeitos de lipofuscinose ceróide seu resultado foi inconclusivo. O estudo ultrastrutural de biópsias de conjuntiva é um instrumento importante para o diagnóstico de doenças metabólicas do SNC.

  4. Malformações do sistema nervoso central : análise de 157 necrópsias pediátricas

    Directory of Open Access Journals (Sweden)

    NORONHA LÚCIA DE

    2000-01-01

    Full Text Available As malformações do sistema nervoso central (SNC têm sido relatadas como de alta prevalência, acometendo 5 a 10 crianças para 1000 nascidos vivos. Estudamos a frequência das malformações do SNC em 5837 necrópsias pediátricas realizadas no Serviço de Anatomia Patológica do Hospital de Clínicas-UFPR, entre 1960 e 1995. Encontraram-se 157 malformações do SNC, correspondendo a 2,69% das necrópsias. As malformações mais comuns foram os defeitos do tubo neural (61%, incluindo 47 anencefalias e 45 casos classificados no grupo das mieloencefaloceles. As anomalias da vesícula prosencefálica foram responsáveis por 8% das malformações encefálicas, havendo sete casos de holoprosencefalia. Em 3%, as alterações ocorreram na fossa posterior, com três malformações de Arnold-Chiari. No presente estudo, os índices de mortalidade por malformações do SNC foram mais altos no período neonatal.

  5. Avaliação de técnicas de biópsia renal em ovinos Evaluation of renal biopsy techniques in sheep

    Directory of Open Access Journals (Sweden)

    Pedro B. Néspoli

    2010-03-01

    Full Text Available Devido à escassez de trabalhos sobre biópsias renais em ovinos foi desenvolvido um estudo comparativo entre três técnicas de biópsia renal nesta espécie. Neste estudo foram utilizadas nove ovelhas (26,64 kg ±4,86 mestiças (Santa Inês em procedimentos seriados, com intervalos consecutivos de uma semana. Foram avaliados os aspectos clínicos, achados de patologia clínica, o peso das amostras renais, a qualidade histológica, o número de glomérulos e a presença de artefatos no corte histológico da técnica de biópsia percutânea cega, da biópsia guiada por ultrassonografia e do procedimento videolaparoscópico. Não foram observadas alterações hematológicas ou bioquímicas relevantes nos animais submetidos às biópsias renais e as manifestações clínicas detectadas foram leves e transitórias, exceto por um caso de obstrução uretral por coágulo sangüíneo. A técnica percutânea cega foi relacionada à maior ocorrência e gravidade de hematúria, com danos mais graves ao tecido renal e com o único caso de obstrução do fluxo urinário. Na técnica videolaparoscópica, o peso médio das amostras foi superior e a hematúria discreta e transitória. Verificou-se relação direta entre a ocorrência de hematúria grave e a presença de epitélio de transição nas amostras e o número de tentativas utilizado para a obtenção dos fragmentos.Due to lack of studies about renal biopsies in sheep, a comparative study was performed for three renal biopsy techniques in this species. In this study, nine crossbred (Santa Inês ewe lamb (26.64 kg ±4,86 were used in serial procedures with one week consecutive intervals. The clinical aspects, clinical pathological findings, renal sample weights, histology quality, number of glomeruli, and the presence of artifacts in the histology slices were evaluated using the techniques of percutaneous blind biopsy, ultrasound guided biopsies and of videolaparoscopic procedure. No relevant

  6. DOE Hydrogen, Fuel Cells and Infrastructure Technologies Program Integrated Hydrogen Production, Purification and Compression System

    Energy Technology Data Exchange (ETDEWEB)

    Tamhankar, Satish; Gulamhusein, Ali; Boyd, Tony; DaCosta, David; Golben, Mark

    2011-06-30

    The project was started in April 2005 with the objective to meet the DOE target of delivered hydrogen of <$1.50/gge, which was later revised by DOE to $2-$3/gge range for hydrogen to be competitive with gasoline as a fuel for vehicles. For small, on-site hydrogen plants being evaluated at the time for refueling stations (the 'forecourt'), it was determined that capital cost is the main contributor to the high cost of delivered hydrogen. The concept of this project was to reduce the cost by combining unit operations for the entire generation, purification, and compression system (refer to Figure 1). To accomplish this, the Fluid Bed Membrane Reactor (FBMR) developed by MRT was used. The FBMR has hydrogen selective, palladium-alloy membrane modules immersed in the reformer vessel, thereby directly producing high purity hydrogen in a single step. The continuous removal of pure hydrogen from the reformer pushes the equilibrium 'forward', thereby maximizing the productivity with an associated reduction in the cost of product hydrogen. Additional gains were envisaged by the integration of the novel Metal Hydride Hydrogen Compressor (MHC) developed by Ergenics, which compresses hydrogen from 0.5 bar (7 psia) to 350 bar (5,076 psia) or higher in a single unit using thermal energy. Excess energy from the reformer provides up to 25% of the power used for driving the hydride compressor so that system integration improved efficiency. Hydrogen from the membrane reformer is of very high, fuel cell vehicle (FCV) quality (purity over 99.99%), eliminating the need for a separate purification step. The hydride compressor maintains hydrogen purity because it does not have dynamic seals or lubricating oil. The project team set out to integrate the membrane reformer developed by MRT and the hydride compression system developed by Ergenics in a single package. This was expected to result in lower cost and higher efficiency compared to conventional hydrogen production

  7. Direct-hydrogen-fueled proton-exchange-membrane fuel cell system for transportation applications

    Energy Technology Data Exchange (ETDEWEB)

    Oei, D.; Adams, J.A.; Kinnelly, A.A. [and others

    1997-07-01

    In partial fulfillment of the U.S. Department of Energy Contract No. DE-ACO2-94CE50389, {open_quotes}Direct Hydrogen-Fueled Proton-Exchange-Membrane (PEM) Fuel Cell System for Transportation Applications{close_quotes}, this conceptual vehicle design report addresses the design and packaging of battery augmented fuel cell powertrain vehicles. This report supplements the {open_quotes}Conceptual Vehicle Design Report - Pure Fuel Cell Powertrain Vehicle{close_quotes} and includes a cost study of the fuel cell power system. The three classes of vehicles considered in this design and packaging exercise are the same vehicle classes that were studied in the previous report: the Aspire, representing the small vehicle class; the AIV (Aluminum Intensive Vehicle) Sable, representing the mid-size vehicle; and the E-150 Econoline, representing the van-size class. A preliminary PEM fuel cell power system manufacturing cost study is also presented. As in the case of the previous report concerning the {open_quotes}Pure Fuel Cell Powertrain Vehicle{close_quotes}, the same assumptions are made for the fuel cell power system. These assumptions are fuel cell system power densities of 0.33 kW/ka and 0.33 kW/l, platinum catalyst loading of less than or equal to 0.25 mg/cm{sup 2} total, and hydrogen tanks containing compressed gaseous hydrogen under 340 atm (5000 psia) pressure. The batteries considered for power augmentation of the fuel cell vehicle are based on the Ford Hybrid Electric Vehicle (HEV) program. These are state-of-the-art high power lead acid batteries with power densities ranging from 0.8 kW/kg to 2 kW/kg. The results reported here show that battery augmentation provides the fuel cell vehicle with a power source to meet instant high power demand for acceleration and start-up. Based on the assumptions made in this report, the packaging of the battery augmented fuel cell vehicle appears to be as feasible as the packaging of the pure fuel cell powered vehicle.

  8. Biópsia com agulha grossa guiada por ultrassonografia para o diagnóstico dos tumores fibroepiteliais da mama Ultrasound-guided core needle biopsy for the diagnosis of fibroepithelial breast tumors

    Directory of Open Access Journals (Sweden)

    Marcos Desidério Ricci

    2011-01-01

    Full Text Available OBJETIVO: avaliar a taxa de concordância da biópsia percutânea com agulha grossa guiada por ultrassom seguida pela biópsia excisional em nódulos de mama palpáveis, sugestivos de tumores fibroepiteliais. MÉTODO: estudo retrospectivo que selecionou 70 biópsias com diagnóstico histológico de tumor fibroepitelial em 67 dentre 531 pacientes com lesões mamárias submetidas à biópsia percutânea com agulha grossa guiada por ultrassonografia, com transdutor linear de alta frequência (7.5 MHz, utilizando pistola automática Bard-Magnum e agulha 14 gauge. Foram incluídos os casos com diagnóstico de tumor fibroepitelial na biópsia percutânea ou biópsia excisional. Biópsias com diagnóstico histopatológico de fibroesclerose também foram incluídas no estudo. A força da concordância entre o resultado da biópsia percutânea e da biópsia excisional foi medida pelo coeficiente de Kappa. RESULTADOS: a biópsia excisional revelou 40 casos de fibroadenoma (57,1%, 19 de tumor filoide (27,2% e 11 de fibroesclerose (15,7%. A taxa de concordância para o fibroadenoma foi substancial (k = 0,68; IC95% = 0,45 - 0,91, quase perfeita para o tumor filoide (k = 0,81; IC95% = 0,57 - 1,0 e moderada para a fibroesclerose (k = 0,58; IC95% = 0,36 - 0,90. CONCLUSÕES: a biópsia percutânea com agulha grossa é propedêutica minimamente invasiva que tem taxas de concordância com a biópsia excisional, de "substancial" a "quase perfeita". A fibroesclerose deve ser considerada no diagnóstico diferencial dos tumores fibroepiteliais.PURPOSE: to evaluate the concordance rate of ultrasound-guided core needle biopsy followed by excisional biopsy in palpable breast lumps, suggestive of fibroepithelial tumors. METHOD: a retrospective study included 70 biopsies with a histological diagnosis of fibroepithelial tumor in 67 out of 531 patients with breast lesions submitted to ultrasound-guided core needle biopsy with a high frequency (7.5 MHz linear transducer

  9. Ash removal by hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Rank, V.; von Hartmann, G.B.

    1942-10-17

    This method for the production of high-quality electrode coke involved the hydrogenation of coal to a filterable bitumen product. The hydrogenation and splitting processes were carried out to end at high-molecular-weight bitumens with some lighter oils produced. Variations in temperature, pressure, and throughput determined the type and amount of bitumens. Proper conditions allowed sufficient middle oil for recirculation as pasting oil as well as for increasing filterability by dilution. This partial hydrogenation could be performed without the addition of hydrogen, if hydrogen-producing aromatic compounds, such as tetraline or cresol, were used as pasting oils. For 700-atm hydrogenation, it was found that the Upper Silesian coal was the best with respect to yield, filterability, and recovery of the recycle oils. The lower pressures gave a better filterability while sacrificing yield and recycle oil. The more severe the hydrogenating conditions, the lighter the bitumens and the lower the melting point. For the range of 300 to 600 atm, it was found that filterability improved with increased temperature and decreased with a pressure gain. Larger throughputs caused relatively moderate decreases in filterability. The use of iron catalysts decreased filterability while changing gas and pasting-oil content had little effect. The optimum conditions established a pasting-oil equilibrium with the best filterability. Greater degrees of hydrogenation or splitting produced more recycle middle oils but decreased filterability, thus only the necessary paste oil was produced. By selecting proper conditions, an ashfree bituminous binder could be produced, as used in the production of the Soederberg electrode. 2 tables, 2 graphs

  10. Fatores preditivos de metástases axilares em pacientes com câncer de mama e biópsia de linfonodo sentinela positivo

    Directory of Open Access Journals (Sweden)

    Olívio Feitosa Costa Neto

    Full Text Available RESUMO Objetivo: avaliar os fatores de risco para presença de doença metastática axilar não sentinela em pacientes com câncer de mama e biópsia do linfonodo sentinela positiva. Métodos: estudo transversal, retrospectivo, de mulheres com câncer mamário operadas no Instituto do Câncer do Ceará, entre os anos de 2002 e 2012 e submetidas à biópsia de linfonodo sentinela. Resultados: de 946 pacientes com câncer de mama, 331 foram submetidas à biópsia de linfonodo sentinela, que foi positiva em 83. Estas foram submetidas à linfadenectomia axilar e 39 (46% apresentaram metástases em outros linfonodos axilares. As variáveis que foram significantes para doença axilar adicional foram Ki67>14 (p=0,043, presença de invasão angiolinfática (p=0,01 e tamanho tumoral (p=0,027. Não foi observado associação com receptores de estrogênio, progesterona, grau tumoral e Her-2. Discussão: a presença de invasão angiolinfática e tamanho tumoral tambémjáforam relacionados à metástase axilar adicional em outros estudos. Além destas variáveis observou-se o mesmo efeito preditivo quando avaliamos o Ki67. A validação destes resultados poderá permitira customização do tratamento do câncer de mama, podendo reduzir sua morbidade. Conclusão: invasão angiolinfática, tamanho tumoral (T3/T4 e Ki67>14 foram fatores preditivos de acometimento de metástase axilar além do linfonodo sentinela.

  11. Técnica de biópsia hepática em eqüino por laparoscopia Hepatic biopsy in horses by laparoscopy

    Directory of Open Access Journals (Sweden)

    Luis Cláudio Lopes Correia da Silva

    2002-06-01

    Full Text Available Este trabalho experimental objetivou a avaliação do uso da laparoscopia para biópsia hepática em eqüino e o estudo das possíveis alterações clínicas e laboratoriais decorrentes de tal procedimento. Foram utilizados 10 animais, os quais foram submetidos a procedimento cirúrgico em posição quadrupedal, por abordagem pelo flanco direito, no 17º espaço intercostal, após jejum alimentar e hídrico de 36 e 18 horas respectivamente. A avaliação pós-operatória constou de exame físico diário e colheita de amostras de sangue seriadas. O procedimento possibilitou inspeção dos órgãos e estruturas anatômicas localizados dorsalmente à direita da cavidade abdominal, favorecendo a escolha do local de biópsia hepática. Não foram observadas alterações no exame físico dos animais. Os exames hematológicos e de função hepática não apresentaram alterações significativas. Concluiu-se que o emprego da laparoscopia para realização de biópsia hepática em eqüino é simples, eficaz e seguro.The purpose of this research was to evaluate the use of laparoscopy in obtaining hepatic biopsy in horses and to determine a possible clinical and laboratorial changes related to the procedure. Ten animals were submitted to 36 hours of fastening and 18 hours of water deprivation and then operated in the standing position, through a right flank approach at the level of the 17th intercostal space. Post-operative evaluation consisted of daily physical examination and seriated blood sampling. The procedure allowed for wide visualization of the viscera and anatomical structures located on the right side of the abdominal cavity, favouring the choice of the spot for hepatic biopsy collection. No changes were noted in the physical state of the animals and alterations in hemogram and hepatic function tests were not statistically significant. It was concluded that laparoscopy is a simple, effective and safe technique for obtaining hepatic biopsy

  12. Hydrogen-rich gas generator

    Science.gov (United States)

    Houseman, J.; Cerini, D. J. (Inventor)

    1976-01-01

    A process and apparatus are described for producing hydrogen-rich product gases. A spray of liquid hydrocarbon is mixed with a stream of air in a startup procedure and the mixture is ignited for partial oxidation. The stream of air is then heated by the resulting combustion to reach a temperature such that a signal is produced. The signal triggers a two way valve which directs liquid hydrocarbon from a spraying mechanism to a vaporizing mechanism with which a vaporized hydrocarbon is formed. The vaporized hydrocarbon is subsequently mixed with the heated air in the combustion chamber where partial oxidation takes place and hydrogen-rich product gases are produced.

  13. Hydrogen Embrittlement

    Science.gov (United States)

    Woods, Stephen; Lee, Jonathan A.

    2016-01-01

    Hydrogen embrittlement (HE) is a process resulting in a decrease in the fracture toughness or ductility of a metal due to the presence of atomic hydrogen. In addition to pure hydrogen gas as a direct source for the absorption of atomic hydrogen, the damaging effect can manifest itself from other hydrogen-containing gas species such as hydrogen sulfide (H2S), hydrogen chloride (HCl), and hydrogen bromide (HBr) environments. It has been known that H2S environment may result in a much more severe condition of embrittlement than pure hydrogen gas (H2) for certain types of alloys at similar conditions of stress and gas pressure. The reduction of fracture loads can occur at levels well below the yield strength of the material. Hydrogen embrittlement is usually manifest in terms of singular sharp cracks, in contrast to the extensive branching observed for stress corrosion cracking. The initial crack openings and the local deformation associated with crack propagation may be so small that they are difficult to detect except in special nondestructive examinations. Cracks due to HE can grow rapidly with little macroscopic evidence of mechanical deformation in materials that are normally quite ductile. This Technical Memorandum presents a comprehensive review of experimental data for the effects of gaseous Hydrogen Environment Embrittlement (HEE) for several types of metallic materials. Common material screening methods are used to rate the hydrogen degradation of mechanical properties that occur while the material is under an applied stress and exposed to gaseous hydrogen as compared to air or helium, under slow strain rates (SSR) testing. Due to the simplicity and accelerated nature of these tests, the results expressed in terms of HEE index are not intended to necessarily represent true hydrogen service environment for long-term exposure, but rather to provide a practical approach for material screening, which is a useful concept to qualitatively evaluate the severity of

  14. Hydrogen production costs -- A survey

    Energy Technology Data Exchange (ETDEWEB)

    Basye, L.; Swaminathan, S.

    1997-12-04

    Hydrogen, produced using renewable resources, is an environmentally benign energy carrier that will play a vital role in sustainable energy systems. The US Department of Energy (DOE) supports the development of cost-effective technologies for hydrogen production, storage, and utilization to facilitate the introduction of hydrogen in the energy infrastructure. International interest in hydrogen as an energy carrier is high. Research, development, and demonstration (RD and D) of hydrogen energy systems are in progress in many countries. Annex 11 of the International Energy Agency (IEA) facilitates member countries to collaborate on hydrogen RD and D projects. The United States is a member of Annex 11, and the US representative is the Program Manager of the DOE Hydrogen R and D Program. The Executive Committee of the Hydrogen Implementing Agreement in its June 1997 meeting decided to review the production costs of hydrogen via the currently commercially available processes. This report compiles that data. The methods of production are steam reforming, partial oxidation, gasification, pyrolysis, electrolysis, photochemical, photobiological, and photoelectrochemical reactions.

  15. BIÓPSIA PULMONAR EM BEZERROS COM BRONCOPNEUMONIA INDUZIDA PELA Mannheimia haemolytica PULMONAR BIOPSY IN CALVES WITH BRONCHOPNEUMONIA INDUCED BY Mannheimia haemolytica

    Directory of Open Access Journals (Sweden)

    Daniel Pessoa Gomes da Silva

    2009-09-01

    Full Text Available Com o propósito de avaliar a segurança, a eficácia diagnóstica da biópsia pulmonar e comparar a possível ocorrência de complicações decorrentes da técnica, entre bezerros sadios e com broncopneumonia induzida, utilizaram-se dez bezerros (G1 sadios e vinte bezerros portadores de broncopneumonia, divididos em quatro grupos de cinco bezerros (G2 a G5, os quais foram biopsiados 12, 24, 48 e 72 horas após a inoculação com Mannheimia haemolytica, respectivamente. A presença de crepitação grossa, som submaciço à percussão e as alterações radiográficas auxiliaram no diagnóstico da broncopneumonia e localizaram a área pulmonar a ser biopsiada nos grupos G2 a G5. As alterações microscópicas, visualizadas nos animais do grupo G2 a G5, foram as de broncopneumonia fibrinopurulenta. Nos bezerros do grupo G1 as alterações relacionadas à técnica foram: tosse, epistaxe, dispneia mista, taquipneia e taquicardia. Cinco (25% bezerros com broncopneumonia desenvolveram hemotórax após a biópsia e as alterações relacionadas à técnica foram: taquipneia, taquicardia, tosse, dispneia mista, apatia, mucosas pálidas e decúbito. Conclui-se que a biópsia pulmonar permite o diagnóstico de broncopneumonia em bezerros, contudo as complicações decorrentes da técnica limitam o seu uso apenas nas situações em que os métodos convencionais não tenham possibilitado o diagnóstico.

    PALAVRAS-CHAVES: Bezerros, biópsia pulmonar, broncopneumonia, Mannheimia haemolytica.

    The purpose of this study was to evaluate the safety and diagnostic efficacy of lung biopsy and to compare the possible occurrence of complications due to this technique in healthy calves and in calves with bronchopneumonia. Thirty Holstein calves were divided into a group of ten healthy animals (G1 and into four experimental groups (G2 to G5 of five calves each

  16. Características das encefalites em autópsias - aspectos epidemiológicos e morfológicos.

    OpenAIRE

    Terra, Sílvia Azevedo

    2007-01-01

    O termo encefalite significa inflamação do parênquima encefálico e dentre as possíveis etiologias da doença, destacamos a infecciosa, que entre outros agentes, pode ser causada por vírus, fungos, bactérias, protozoários e metazoários. Neste estudo retrospectivo, o objetivo foi descrever os dados epidemiológicos e morfológicos das encefalites em pacientes autopsiados no HE/UFTM no período de 1976 a 1986. Revisamos 1.267 laudos de autópsias e coletamos dados referentes à idade, ao gêne...

  17. Características das encefalites em autópsias: aspectos epidemiológicos e morfológicos.

    OpenAIRE

    Terra, Sílvia Azevedo

    2007-01-01

    O termo encefalite significa inflamação do parênquima encefálico e dentre as possíveis etiologias da doença, destacamos a infecciosa, que entre outros agentes, pode ser causada por vírus, fungos, bactérias, protozoários e metazoários. Neste estudo retrospectivo, o objetivo foi descrever os dados epidemiológicos e morfológicos das encefalites em pacientes autopsiados no HE/UFTM no período de 1976 a 1986. Revisamos 1.267 laudos de autópsias e coletamos dados referentes à idade, ao gêne...

  18. Biópsia hepática por laparotomia paracostal em bovinos e búfalos Paracostal liver biopsy in cattle and buffalo

    Directory of Open Access Journals (Sweden)

    Antonio Humberto Hamad Minervino

    2009-06-01

    Full Text Available A técnica de biópsia hepática em ruminantes tem importante valor no diagnóstico clínico de doenças tóxicas e metabólicas, em especial nos desequilíbrios minerais. As técnicas mais comumente utilizadas restringem análises devido ao limitado volume de tecido obtido. No presente trabalho, avaliou-se o uso de uma técnica de biópsia hepática por laparotomia paracostal em bovinos e búfalos. Foram utilizados 10 bovinos e 10 búfalos hígidos. Os animais foram mantidos em estação, sedados com xilazina e infiltrados localmente com lidocaína e epinefrina. O acesso à cavidade abdominal foi realizado por meio de uma incisão dorso-ventral de 15cm no flanco direito, iniciada ventralmente (cerca de 4-5cm ao processo transverso da 2a ou 3a vértebra lombar e situada caudalmente (cerca de 4cm e paralelamente à 13a costela, obtendo-se visualização do fígado. Foi então realizado pinçamento do bordo caudal do órgão com pinça Doyen para remoção de fragmento hepático (2 a 4g. Procedeu-se o fechamento da cavidade abdominal como de rotina. Foram analisados os parâmetros bioquímicos e hematológicos antes do procedimento (tempo zero e após 24 horas, 48 horas, 5 dias e 10 dias após a biópsia. Todas as variáveis bioquímicas estudadas retornaram aos valores basais 5 e 10 dias após o procedimento nos bovinos e búfalos, respectivamente. O tempo médio de cirurgia por animal foi de 25 minutos. A biópsia hepática por laparotomia paracostal demonstrou ser uma técnica eficaz e de baixo risco à saúde dos animais, permitindo a coleta de suficiente quantidade de tecido hepática para realização de múltiplas análises.Liver biopsy in ruminants is an important technique for clinical diagnosis of toxic and metabolic diseases, especially mineral disorders. The most frequent procedures used so far results in an small amount of liver and not enough for multiple tests. The present study aims to evaluate the efficacy of paracostal laparotomy

  19. Enthalpy measurement of coal-derived liquids. Quarterly technical progress report, July--September 1977. [155 to 742 degrees F and 150, 200, 500, 1000 and 1500 psia

    Energy Technology Data Exchange (ETDEWEB)

    Kidnay, A.J.; Yesavage, V.F.

    1977-10-15

    Coal-derived liquids are a new and vital class of industrial compounds, but have thermodynamic properties that are largely unknown and, presently, unpredictable. The objective of this research is to measure one of the most important thermodynamic properties, the enthalpy, for representative coal-derived liquids over the pressure and temperature regions most likely to be encountered in both liquefaction and processing systems. Experimental measurements were made on a distillate from a coal-derived liquid sample produced with the Synthoil process. The measurements extend from 155 to 742/sup 0/F at pressures of 150, 200, 500, 1000, and 1500 psia. Enthalpy measurements were also started on a naphtha cut from a coal-derived liquid produced by the SRC-I process. These naphtha measurements are approximately 60 percent complete.

  20. Hydrogen Bibliography

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-01

    The Hydrogen Bibliography is a compilation of research reports that are the result of research funded over the last fifteen years. In addition, other documents have been added. All cited reports are contained in the National Renewable Energy Laboratory (NREL) Hydrogen Program Library.

  1. Hydrogen exchange

    DEFF Research Database (Denmark)

    Jensen, Pernille Foged; Rand, Kasper Dyrberg

    2016-01-01

    Hydrogen exchange (HX) monitored by mass spectrometry (MS) is a powerful analytical method for investigation of protein conformation and dynamics. HX-MS monitors isotopic exchange of hydrogen in protein backbone amides and thus serves as a sensitive method for probing protein conformation...... and dynamics along the entire protein backbone. This chapter describes the exchange of backbone amide hydrogen which is highly quenchable as it is strongly dependent on the pH and temperature. The HX rates of backbone amide hydrogen are sensitive and very useful probes of protein conformation......, as they are distributed along the polypeptide backbone and form the fundamental hydrogen-bonding networks of basic secondary structure. The effect of pressure on HX in unstructured polypeptides (poly-dl-lysine and oxidatively unfolded ribonuclease A) and native folded proteins (lysozyme and ribonuclease A) was evaluated...

  2. Hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Donath, E.

    1942-10-16

    This report mentioned that not very severe demands for purity were made on the hydrogen used in hydrogenation of coal or similar raw materials, because the catalysts were not very sensitive to poisoning. However, the hydrogenation plants tried to remove most impurities anyway by means of oil washes. The report included a table giving the amount of wash oil used up and the amount of hydrogen lost by dissolving into the wash oil used up and the amount of hydrogen lost by dissolving into the wash oil in order to remove 1% of various impurities from 1000 m/sup 3/ of the circulating gas. The amounts of wash oil used up were 1.1 m/sup 3/ for removing 1% nitrogen, 0.3 m/sup 3/ for 1% carbon monoxide, 0.03 m/sup 3/ for 1% methane. The amount of hydrogen lost was 28 m/sup 3/ for 1% nitrogen, 9 m/sup 3/ for 1% methane and ranged from 9 m/sup 3/ to 39 m/sup 3/ for 1% carbon monoxide and 1 m/sup 3/ to 41 m/sup 3/ for carbon dioxide depending on whether the removal was done in liquid phase or vapor phase and with or without reduction of the oxide to methane. Next the report listed and described the major processes used in German hydrogenation plants to produce hydrogen. Most of them produced water gas, which then had its carbon monoxide changed to carbon dioxide, and the carbon oxides washed out with water under pressure and copper hydroxide solution. The methods included the Winkler, Pintsch-Hillebrand, and Schmalfeldt-Wintershall processes, as well as roasting of coke in a rotating generator, splitting of gases formed during hydrogenation, and separation of cokery gas into its components by the Linde process.

  3. Hydrogen/Air Fuel Nozzle Emissions Experiments

    Science.gov (United States)

    Smith, Timothy D.

    2001-01-01

    The use of hydrogen combustion for aircraft gas turbine engines provides significant opportunities to reduce harmful exhaust emissions. Hydrogen has many advantages (no CO2 production, high reaction rates, high heating value, and future availability), along with some disadvantages (high current cost of production and storage, high volume per BTU, and an unknown safety profile when in wide use). One of the primary reasons for switching to hydrogen is the elimination of CO2 emissions. Also, with hydrogen, design challenges such as fuel coking in the fuel nozzle and particulate emissions are no longer an issue. However, because it takes place at high temperatures, hydrogen-air combustion can still produce significant levels of NOx emissions. Much of the current research into conventional hydrocarbon-fueled aircraft gas turbine combustors is focused on NOx reduction methods. The Zero CO2 Emission Technology (ZCET) hydrogen combustion project will focus on meeting the Office of Aerospace Technology goal 2 within pillar one for Global Civil Aviation reducing the emissions of future aircraft by a factor of 3 within 10 years and by a factor of 5 within 25 years. Recent advances in hydrocarbon-based gas turbine combustion components have expanded the horizons for fuel nozzle development. Both new fluid designs and manufacturing technologies have led to the development of fuel nozzles that significantly reduce aircraft emissions. The goal of the ZCET program is to mesh the current technology of Lean Direct Injection and rocket injectors to provide quick mixing, low emissions, and high-performance fuel nozzle designs. An experimental program is planned to investigate the fuel nozzle concepts in a flametube test rig. Currently, a hydrogen system is being installed in cell 23 at NASA Glenn Research Center's Research Combustion Laboratory. Testing will be conducted on a variety of fuel nozzle concepts up to combustion pressures of 350 psia and inlet air temperatures of 1200 F

  4. Extensive analysis of hydrogen costs

    Energy Technology Data Exchange (ETDEWEB)

    Guinea, D.M.; Martin, D.; Garcia-Alegre, M.C.; Guinea, D. [Consejo Superior de Investigaciones Cientificas, Arganda, Madrid (Spain). Inst. de Automatica Industrial; Agila, W.E. [Acciona Infraestructuras, Alcobendas, Madrid (Spain). Dept. I+D+i

    2010-07-01

    Cost is a key issue in the spreading of any technology. In this work, the cost of hydrogen is analyzed and determined, for hydrogen obtained by electrolysis. Different contributing partial costs are taken into account to calculate the hydrogen final cost, such as energy and electrolyzers taxes. Energy cost data is taken from official URLs, while electrolyzer costs are obtained from commercial companies. The analysis is accomplished under different hypothesis, and for different countries: Germany, France, Austria, Switzerland, Spain and the Canadian region of Ontario. Finally, the obtained costs are compared to those of the most used fossil fuels, both in the automotive industry (gasoline and diesel) and in the residential sector (butane, coal, town gas and wood), and the possibilities of hydrogen competing against fuels are discussed. According to this work, in the automotive industry, even neglecting subsidies, hydrogen can compete with fossil fuels. Hydrogen can also compete with gaseous domestic fuels. Electrolyzer prices were found to have the highest influence on hydrogen prices. (orig.)

  5. Hydrogen program overview

    Energy Technology Data Exchange (ETDEWEB)

    Gronich, S. [Dept. of Energy, Washington, DC (United States). Office of Utility Technologies

    1997-12-31

    This paper consists of viewgraphs which summarize the following: Hydrogen program structure; Goals for hydrogen production research; Goals for hydrogen storage and utilization research; Technology validation; DOE technology validation activities supporting hydrogen pathways; Near-term opportunities for hydrogen; Market for hydrogen; and List of solicitation awards. It is concluded that a full transition toward a hydrogen economy can begin in the next decade.

  6. Hydrogen usage

    Energy Technology Data Exchange (ETDEWEB)

    1942-10-22

    This short tabular report listed the number of m/sup 3/ of hydrogen required for a (metric) ton of product for various combinations of raw material and product in a hydrogenation procedure. In producing auto gasoline, bituminous coal required 2800 m/sup 3/, brown coal required 2400 m/sup 3/, high-temperature-carbonization tar required 2100 m/sup 3/, bituminous coal distillation tar required 1300 m/sup 3/, brown-coal low-temperature-carbonization tar required 850 m/sup 3/, petroleum residues required 900 m/sup 3/, and gas oil required 500 m/sup 3/. In producing diesel oil, brown coal required 1900 m/sup 3/, whereas petroleum residues required 500 m/sup 3/. In producing diesel oil, lubricants, and paraffin by the TTH (low-temperature-hydrogenation) process, brown-coal low-temperature-carbonization tar required 550 m/sup 3/. 1 table.

  7. Hydrogen energy systems studies. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.M.; Kreutz, T.; Kartha, S.; Iwan, L.

    1996-08-13

    The results of previous studies suggest that the use of hydrogen from natural gas might be an important first step toward a hydrogen economy based on renewables. Because of infrastructure considerations (the difficulty and cost of storing, transmitting and distributing hydrogen), hydrogen produced from natural gas at the end-user`s site could be a key feature in the early development of hydrogen energy systems. In the first chapter of this report, the authors assess the technical and economic prospects for small scale technologies for producing hydrogen from natural gas (steam reformers, autothermal reformers and partial oxidation systems), addressing the following questions: (1) What are the performance, cost and emissions of small scale steam reformer technology now on the market? How does this compare to partial oxidation and autothermal systems? (2) How do the performance and cost of reformer technologies depend on scale? What critical technologies limit cost and performance of small scale hydrogen production systems? What are the prospects for potential cost reductions and performance improvements as these technologies advance? (3) How would reductions in the reformer capital cost impact the delivered cost of hydrogen transportation fuel? In the second chapter of this report the authors estimate the potential demand for hydrogen transportation fuel in Southern California.

  8. Correlação entre a graduação histológica de biópsias e do espécimen cirúrgico em câncer da prostata

    Directory of Open Access Journals (Sweden)

    José Cury

    Full Text Available Foram estudados, retrospectivamente, os prontuários de 120 pacientes com câncer localizado da próstata nos estádios clínicos T1, T2 e T3a e que foram submetidos a 1infadenectomia ilíaca e a cirurgia radical da próstata. Todos haviam sido graduados pela escala de Gleason através de biópsias da próstata guiadas pela ultra-sonografia transretal. Correlacionamos a graduação histo1ógica destas biópsias da próstata com a graduação final obtida no exame da peça cirúrgica correspondente e obtivemos exata concordância em 39 pacientes (32,50%. Ao considerarmos a concordância de ± 1unidade, observamos concordância de resultado em 81 pacientes (67,50%. A subgraduação histológica das biópsias prostáticas foi encontrada em 75 pacientes (62,50% dos casos.

  9. Paralisia do nervo ulnar na lepra sem alterações cutâneas: biópsia do ramo superficial do nervo ulnar na mão

    Directory of Open Access Journals (Sweden)

    FREITAS MARCOS R. G. DE

    1998-01-01

    Full Text Available A lepra constitui causa frequente de acometimento de nervos periféricos, em nosso meio. O sistema nervoso periférico é acometido por vezes sem que haja alterações cutâneas: é a chamada forma neurítica pura. Nessa variante, o nervo mais afetado é o ulnar. Nos casos de acometimento isolado de nervos periféricos somente a feitura de biópsia de nervo conduzirá ao diagnóstico. Assim, resolvemos realizar biópsia do ramo sensitivo superficial do nervo ulnar na mão em 17 pacientes com paresia ou paralisia desse nervo e espessamento do mesmo na altura do cotovelo. Os principais achados foram: redução do número de fibras mielínicas em 14 casos, infiltrado inflamatório em 13, fibrose em 12, desmielinização e remielinização em 9, presença de granuloma em 6 e visualização do Mycobacterium leprae em 5. Concluímos que a biópsia do ramo sensitivo superficial do nervo ulnar na mão é um bom meio diagnóstico de lepra em pacientes com acometimento desse nervo

  10. Versatile Hydrogen

    Indian Academy of Sciences (India)

    Hydrogen is probably the most intriguing ele- ment in the periodic table. Although it is only the seventh most abundant element on earth, it is the most abundant element in the uni- verse. It combines with almost all the ele- ments of the periodic table, except for a few transition elements, to form binary compounds of the type E.

  11. Hydrogen in metals

    CSIR Research Space (South Africa)

    Carter, TJ

    2001-04-01

    Full Text Available The effects of hydrogen on various metals and the use of metal hydrides for hydrogen storage are discussed. The mechanisms of, and differences between, hydrogen embrittlement and hydrogen attack of ferritic steels are compared, common sources...

  12. MELAS: clinical features, muscle biopsy and molecular genetics MELAS: manifestações clínicas, biópsia muscular e estudo molecular

    Directory of Open Access Journals (Sweden)

    Paulo José Lorenzoni

    2009-09-01

    Full Text Available OBJECTIVE: The aim of the study was to analyze a series of Brazilian patients suffering from MELAS. METHOD: Ten patients with MELAS were studied with correlation between clinical findings, laboratorial data, electrophysiology, histochemical and molecular features. RESULTS: Blood lactate was increased in eight patients. Brain image studies revealed a stroke-like pattern in all patients. Muscle biopsy showed ralled-red fibers (RRF in 90% of patients on modified Gomori-trichrome and in 100% on succinate dehydrogenase stains. Cytochrome c oxidase stain analysis indicated deficient activity in one patient and subsarcolemmal accumulation in seven patients. Strongly succinate dehydrogenase-reactive blood vessels (SSV occurred in six patients. The molecular analysis of tRNA Leu(UUR gene by PCR/RLFP and direct sequencing showed the A3243G mutation on mtDNA in 4 patients. CONCLUSION: The muscle biopsy often confirmed the MELAS diagnosis by presence of RRF and SSV. Molecular analysis of tRNA Leu(UUR gene should not be the only diagnostic criteria for MELAS.OBJETIVO: O objetivo deste estudo foi analisar uma série de pacientes brasileiros portadores de MELAS. MÉTODO: Dez pacientes com MELAS foram estudados com correlação entre manifestações clínicas, alterações laboratoriais, estudo eletrofisiológico, histoquímico e molecular. RESULTADOS: O nível de lactato sérico estava aumentado em 8 pacientes. O estudo das imagens do crânio revelou padrão semelhante ao de AVC isquêmico em todos os pacientes. A biópsia muscular mostrou fibras rajadas vermelhas (RRF em 90% dos pacientes na coloração pelo tricrômio de Gomori modificado e em 100% na reação histoquímica pela desidrogenase succicínica (SDH. A análise da coloração pela citocromo c oxidase indicou atividade deficiente em um paciente e acúmulo subsarcolemal em sete pacientes. Vasos com forte reação para SDH (SSV ocorreram em seis pacientes. O estudo molecular do gene tRNA Leu(UUR por

  13. Observar, ouvir, compartilhar: trabalho de campo para autópsias psicossociais Watching, listening and sharing: field work for psychosocial autopsies

    Directory of Open Access Journals (Sweden)

    Maria Cecília de Souza Minayo

    2012-08-01

    Full Text Available O artigo descreve as etapas de realização do trabalho de campo da pesquisa. É possível prevenir a antecipação do fim? Suicídio de Idosos no Brasil e possibilidades de Atuação do Setor de Saúde, realizada em 10 municípios das cinco regiões do país. A amostra composta por 51 autópsias psicossociais abrangeu cinco idosos que faleceram por suicídio em nove municípios e seis em um deles. Oitenta e quatro familiares foram entrevistados. Trabalhou-se com um roteiro denominado autópsia psicossocial e com observação do contexto. Cada entrevista durou 60 minutos em média, e na maioria dos casos, houve mais de um encontro com os familiares. O estudo foi construído por meio de um processo coletivo que abrangeu compartilhamento da revisão bibliográfica, discussão do universo, das amostras, das estratégias de abordagem, dos resultados de campo e das análises empíricas. Este artigo destaca a preparação teórica, conceitual e prática dos pesquisadores; o processo de elaboração dos instrumentos para o trabalho de campo; informações sobre as fontes de dados existentes e sobre as efetivamente acessadas; apresentação de credencial institucional; entrada no contexto das famílias, dificuldades e estratégias para realização do estudo empírico; entrada e saída do campo; e impacto da pesquisa sobre os investigadores.The article describes the research realization phases of field work in ten municipalities in five regions entitled "Is it possible to prevent the anticipation of the end? Suicide among the elderly in Brazil and the possibilities for action by the Health Sector." The sample comprises 51 psychosocial autopsies of 5 elderly people who committed suicide in 9 locations and 6 in another. 84 family members were interviewed. Semi-structured psychosocial autopsies and contextual observations were used. Each interview lasted 60 minutes on average and in the majority of the cases there was more than one encounter with family

  14. Hydrogen. A small molecule with large impact

    Energy Technology Data Exchange (ETDEWEB)

    Gehrke, H.; Ruthardt, K.; Mathiak, J.; Roosen, C. [Uhde GmbH, Dortmund (Germany)

    2010-12-30

    The first section of the presentation will provide general information about hydrogen including physical data, natural abundance, production and consumption figures. This will be followed by detailed information about current industrial production routes for hydrogen. Main on-purpose production for hydrogen is by classical steam reforming (SR) of natural gas. A brief overview of most important steps in stream reforming is given including reforming section, CO conversion and gas purification. Also the use of heavier than methane feedstocks and refinery off-gases is discussed. Alternative routes for hydrogen production or production of synthesis gas are autothermal reforming (ATR) or partial oxidation (POX). Pros and Cons for each specific technology are given and discussed. Gasification, especially gasification of renewable feedstocks, is a further possibility to produce hydrogen or synthesis gas. New developments and current commercial processes are presented. Hydrogen from electrolysis plants has only a small share on the hydrogen production slate, but in some cases this hydrogen is a suitable feedstock for niche applications with future potential. Finally, production of hydrogen by solar power as a new route is discussed. The final section focuses on the use of hydrogen. Classical applications are hydrogenation reactions in refineries, like HDS, HDN, hydrocracking and hydrofinishing. But, with an increased demand for liquid fuels for transportation or power supply, hydrogen becomes a key player in future as an energy source. Use of hydrogen in synthesis gas for the production of liquid fuels via Fischer-Tropsch synthesis or coal liquefaction is discussed as well as use of pure hydrogen in fuel cells. Additional, new application for biomass-derived feedstocks are discussed. (orig.)

  15. Partial tooth gear bearings

    Science.gov (United States)

    Vranish, John M. (Inventor)

    2010-01-01

    A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

  16. The hydrogen; L'hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    The hydrogen as an energy system represents nowadays a main challenge (in a scientific, economical and environmental point of view). The physical and chemical characteristics of hydrogen are at first given. Then, the challenges of an hydrogen economy are explained. The different possibilities of hydrogen production are described as well as the distribution systems and the different possibilities of hydrogen storage. Several fuel cells are at last presented: PEMFC, DMFC and SOFC. (O.M.)

  17. Hydrogen fuel dispensing station for transportation vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S.P.N.; Richmond, A.A. [Oak Ridge National Lab., TN (United States). Chemical Technology Div.

    1995-07-01

    A technical and economic assessment is being conducted of a hydrogen fuel dispensing station to develop an understanding of the infrastructure requirements for supplying hydrogen fuel for mobile applications. The study includes a process design of a conceptual small-scale, stand-alone, grassroots fuel dispensing facility (similar to the present-day gasoline stations) producing hydrogen by steam reforming of natural gas. Other hydrogen production processes (such as partial oxidation of hydrocarbons and water electrolysis) were reviewed to determine their suitability for manufacturing the hydrogen. The study includes an assessment of the environmental and other regulatory permitting requirements likely to be imposed on a hydrogen fuel dispensing station for transportation vehicles. The assessment concludes that a dispensing station designed to produce 0.75 million standard cubic feet of fuel grade (99.99%+ purity) hydrogen will meet the fuel needs of 300 light-duty vehicles per day. Preliminary economics place the total capital investment (in 1994 US dollars) for the dispensing station at $4.5 million and the annual operating costs at around $1 million. A discounted cash-flow analysis indicates that the fuel hydrogen product price (excluding taxes) to range between $1.37 to $2.31 per pound of hydrogen, depending upon the natural gas price, the plant financing scenario, and the rate of return on equity capital. A report on the assessment is due in June 1995. This paper presents a summary of the current status of the assessment.

  18. Advanced Palladium Membrane Scale-up for Hydrogen Separation

    Energy Technology Data Exchange (ETDEWEB)

    Emerson, Sean; Magdefrau, Neal; She, Ying; Thibaud-Erkey, Catherine

    2012-10-31

    The main objective of this project was to construct, test, and demonstrate a Pd-Cu metallic tubular membrane micro-channel separator capable of producing 2 lb day{sup -1} H{sub 2} at 95% recovery when operating downstream of an actual coal gasifier. A key milestone for the project was to complete a pilot-scale gasifier test by 1 September 2011 and demonstrate the separation of 2 lb day{sup -1} H{sub 2} to verify progress toward the DOE's goals prior to down-selection for larger-scale (100 lb day{sup -1}) hydrogen separator development. Three different pilot-scale (1.5 ft{sup 2}) separators were evaluated downstream of coal gasifiers during four different tests and the key project milestone was achieved in August 2011, ahead of schedule. During three of those tests, all of the separators demonstrated or exceeded the targeted separation rate of 2 lb day{sup -1} H{sub 2}. The separator design was proved to be leak tight and durable in the presence of gasifier exhaust contaminants at temperatures and pressures up to 500 °C and 500 psia. The contaminants in the coal gasifier syngas for the most part had negligible impact on separator performance, with H{sub 2} partial pressure being the greatest determinant of membrane performance. Carbon monoxide and low levels of H{sub 2}S (<39 ppmv) had no effect on H{sub 2} permeability, in agreement with laboratory experiments. However, higher levels of H{sub 2}S (>100 ppmv) were shown to significantly reduce H{sub 2} separation performance. The presence of trace metals, including mercury and arsenic, appeared to have no effect based on the experimental data. Subscale Pd-Cu coupon tests further quantified the impact of H{sub 2}S on irreversible sulfide formation in the UTRC separators. Conditions that have a thermodynamic driving force to form coke were found to reduce the performance of the separators, presumably by blockage of effective separation area with carbon deposits. However, it was demonstrated that both in situ

  19. Discrepâncias clínico-patológicas e achados cardiovasculares em 409 autópsias consecutivas Clinical and pathological discrepancies and cardiovascular findings in 409 consecutive autopsies

    Directory of Open Access Journals (Sweden)

    Aline Fusco Fares

    2011-12-01

    Full Text Available FUNDAMENTO: As discrepâncias entre os diagnósticos clínicos e em autópsia persistem em todo o mundo. OBJETIVO: Avaliamos as autópsias em um hospital-escola para analisar a precisão dos diagnósticos cardiovasculares clínicos em comparação aos achados post-mortem. MÉTODOS: As 409 autópsias consecutivas entre 2003 e 2006 foram analisadas em um hospital terciário de São José do Rio Preto, São Paulo (SP, Brasil. A comparação dos achados cardiovasculares clínicos e patológicos foi realizada por meio da classificação de discrepâncias de Goldman. RESULTADOS: A taxa de autópsia no hospital foi de 8%. As causas cardiovasculares de óbito representavam 42,8% (175 de 409 pacientes dos diagnósticos de autópsia. Em 98 pacientes (56%, houve discrepâncias significativas (classes I e II, o que representa uma grande proporção de diagnósticos equivocados de infarto mesentérico (84,6%, infarto agudo do miocárdio (64,7%, dissecção da aorta (64,2% e embolia pulmonar (62,5%. Foram observadas maiores taxas de concordância para a insuficiência cardíaca congestiva (59% e para o acidente vascular cerebral isquêmico agudo (58,8%. A idade, o sexo, o tempo de permanência e a última unidade de admissão no hospital não foram associados aos critérios de Goldman. CONCLUSÃO: As discrepâncias dos diagnósticos clínicos e em autópsia relativos à morte cardiovascular permanecem elevados no Brasil, a despeito dos recursos tecnológicos disponíveis. Além disso, nossos achados reforçam a importância do exame post-mortem como uma contribuição para a melhoria da assistência médica.BACKGROUND: Discrepancies between clinical and autopsy diagnoses persists worldwide. OBJECTIVE: We evaluated autopsies in a university hospital in order to assess the accuracy of clinical cardiovascular diagnosis compared to postmortem findings. METHODS: Four hundred nine consecutive autopsies between 2003 and 2006 were analyzed in a tertiary-care hospital

  20. O decréscimo vertiginoso das autópsias em um hospital universitário do Brasil nos últimos 20 anos The dramatic decline of the autopsies at a Brazilian university hospital in the last 20 years

    Directory of Open Access Journals (Sweden)

    Fabiana Resende Rodrigues

    2011-08-01

    Full Text Available INTRODUÇÃO: O declínio no número de autópsias em hospitais e instituições universitárias é evento amplamente reportado, inicialmente em países do primeiro mundo e posteriormente em muitos países em desenvolvimento, como o Brasil. As causas para essa tendência são múltiplas e complexas, incluindo aspectos religiosos, familiares e médicos. Entre estes últimos, salientam-se razões diagnósticas, caracterizadas pelo significativo avanço tecnológico na imagenologia, com a suposição de que todos os diagnósticos agora podem ser feitos em vida, e a crescente ansiedade de processos judiciais contra médicos por má prática. OBJETIVO: Demonstrar o decréscimo vertiginoso e drástico do número de autópsias em um hospital universitário no Brasil. MATERIAL E MÉTODO: Avaliou-se o número de registros nos livros de autópsias consecutivas realizadas no Departamento de Patologia do Hospital Universitário Antonio Pedro da Universidade Federal Fluminense (HUAP/UFF, Niterói, Rio de Janeiro, criando um banco dados em tabela do programa Microsoft Excel. RESULTADOS: Durante os anos 1966 a 2009, foram realizadas 23.813 necrópsias, sendo 12.702 de adultos e 11.111 de fetos. Entre os anos 1966 e 1998, foram realizadas mais necrópsias, no total de 23.321, sendo 12.482 de adultos e 10.839 de fetos. Já entre os anos 1999 e 2009, foi observado o declínio acentuado e drástico das mesmas, totalizando apenas 492 necrópsias, sendo 220 de adultos e 272 de fetos. CONCLUSÃO: Acreditamos que a principal causa para esse declínio é a pouca informação da população, que desconhece que o saber é fruto de estudo, pesquisa, prática e aprimoramento.INTRODUCTION: The decline in the number of autopsies at hospitals and university hospitals has been widely reported, initially in developed countries and afterwards in several developing countries including Brazil. The causes for this trend are multiple and complex, encompassing religious, family and

  1. Estudo da biópsia por agulha cortante no diagnóstico histopatológico de lesões bucais = Cutting needle biopsy study in histopathological diagnosis of oral lesions

    Directory of Open Access Journals (Sweden)

    Braga, Ana Maria Corrêa

    2005-01-01

    Full Text Available Objetivo: Estudar a eficácia da biópsia por agulha cortante (BAC no diagnóstico de lesões bucais localizadas em tecidos moles, indicadas para biópsia incisional ou excisional, em 21 pacientes, de ambos os sexos, com idades entre 18 e 80 anos. Materiais e métodos: Para a realização das biópsias foi utilizada uma agulha cortante de 18 Ga × 9 cm. Cada peça foi submetida a três disparos com a agulha obtendo-se três espécimes que após o processamento laboratorial, originaram três lâminas. Para as análises histopatológicas elaborou-se um questionário contendo duas perguntas sobre o diagnóstico dos espécimes que foi aplicado em dois momentos diferentes, com e sem a história clínica. As respostas do questionário, em ambas as etapas, foram comparadas com os diagnósticos conclusivos das peças cirúrgicas removidas anteriormente. Resultados: Os resultados foram elaborados conforme uma escala de valores e submetidos à análise estatística de McNemar, a um nível de significância de 5%. O número de acertos dos diagnósticos específicos obtidos com os espécimes da agulha cortante foi estatisticamente superior em relação ao número de erros. Observou-se também que o número de acertos foi maior quando o examinador respondeu ao questionário com o conhecimento da história clínica. Conclusão: A biópsia por agulha cortante mostrou-se eficaz na elaboração do diagnóstico histopatológico de lesões bucais

  2. Cystic partially differentiated nephroblastoma.

    Science.gov (United States)

    Puvaneswary, M; Macintosh, J; Cassey, J

    2006-06-01

    Cystic partially differentiated nephroblastoma is a relatively rare tumour of the kidney usually affecting infants. Cystic Wilms' tumour and multilocular cystic nephroma should be distinguished from cystic partially differentiated nephroblastoma. Multilocular cystic nephroma is a benign tumour whereas cystic Wilms' tumour is at the malignant end of the range of classification of such tumours. Cystic partially differentiated nephroblastoma may undergo local recurrence but there is no report of metastasis.

  3. Ionization cross section of partially ionized hydrogen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Baimbetov, F B; Kudyshev, Z A [Department of Physics, al - Farabi Kazakh National University, Almaty (Kazakhstan)], E-mail: Bfb77@kazsu.kz, E-mail: Z.Kudyshev@mail.ru

    2008-05-01

    In present work the electron impact ionization cross section is considered. The electron impact ionization cross section is calculated, based on pseudopotential model of interaction between plasma particles which accounts correlation effects. It is calculated with help of two methods: classical and quantum - mechanical (Born approximation). The ionization cross section is compared with corresponding results of other authors and experimental data. It has been shown that it is very important to take into account an influence of the surrounding during consideration of ionization processes.

  4. Partially Hydrogenated Oils and Trans Fats Information for Consumers

    OpenAIRE

    Allen, Karin

    2015-01-01

    Companies have been given until June 2018 to remove PHOs from the foods they produce, or to petition the FDA to allow specific uses for trans fats. The FDA has not banned trans fats. But what does that mean? And how will it change the foods we eat? To help consumers understand the FDA's actions, this fact sheet looks at three questions: What is trans fat? What are PHOs? What will replace PHOs?

  5. Contaminação tumoral em trajeto de biópsia de tumores ósseos malignos primários Tumor contamination in the biopsy path of primary malignant bone tumors

    Directory of Open Access Journals (Sweden)

    Marcelo Parente Oliveira

    2012-10-01

    Full Text Available OBJETIVO: Estudar os fatores possivelmente associados à contaminação tumoral do trajeto de biópsia de tumores ósseos malignos primários. MÉTODO: Foram estudados, retrospectivamente, 35 pacientes submetidos a tratamento cirúrgico com diagnóstico de osteossarcoma, tumor de Ewing e condrossarcoma. A amostra foi analisada para caracterização quanto à técnica de biópsia empregada, tipo histológico do tumor, realização de quimioterapia neoadjuvante, ocorrência de recidiva local e contaminação tumoral no trajeto da biópsia. RESULTADOS: Nos 35 pacientes avaliados ocorreram quatro contaminações (11,43%. Um caso era de osteossarcoma, dois casos de tumor de Ewing e um caso de condrossarcoma, não se observando associação entre o tipo de tumor e a presença de contaminação tumoral no trajeto da biópsia (p = 0,65. Também não se observou associação entre a presença de contaminação tumoral e a técnica de biópsia (p = 0,06. Por outro lado, observou-se associação entre a presença de contaminação tumoral e a ocorrência de recidiva local (p = 0,01 e entre a presença de contaminação e a não realização de quimioterapia neoadjuvante (p = 0,02. CONCLUSÃO: A contaminação tumoral no trajeto de biópsia de tumores ósseos malignos primários esteve associada à ocorrência de recidiva local. Por outro lado, não mostrou ser influenciada pelo tipo de biópsia realizada e pelo tipo histológico de tumor estudado. A quimioterapia neoadjuvante mostrou um efeito protetor contra esta complicação. A despeito desses achados, a contaminação tumoral é uma complicação que deve sempre ser considerada, sendo recomendada a remoção do trajeto da biópsia na cirurgia de ressecção do tumor.OBJECTIVE: To study factors possibly associated with tumor contamination in the biopsy path of primary malignant bone tumors. METHOD: Thirty-five patients who underwent surgical treatment with diagnoses of osteosarcoma, Ewing's tumor and

  6. Stool examination and rectal biopsy in the diagnosis and evaluation of therapy of schistosomiasis mansoni Exame de fezes e biópsia retal no diagnóstico e controle de cura da esquistossomose mansoni

    Directory of Open Access Journals (Sweden)

    Ana Lúcia Teles Rabello

    1992-12-01

    Full Text Available From each of a group of 217 adult males selected through enzyme-immunoassay or skin-test (Group A, six stool samples were examined by both the Lutz/Hoffman, Pons & Janer (Lutz/HPJ and Kato/Katz methods. In addition, one oogram of the rectal mucosa was performed. By these methods, schistosomiasis was detected in 44.7%, 47.5% and 40.1% of the individuals respectively. To evaluate the methods in the assessment of cure, the last 40 patients from group A, treated with a single oral dose of oxamniquine at 15 mg/kg were followed up for six months (Group B. The criteria for parasitological cure included three stool examinations by Kato/Katz and Lutz/HPJ methods, one, three and six months post-treatment and a rectal biopsy between the fourth and sixth months post-treatment. The examinations were negative in 87.5%, 90% and 95% of the patients, respectively. The efficacy of oxamniquine was 82.5% when the three methods were considered together and there was no statistically significant difference between the sensitivity of the individual methods.Em um grupo de 217 adultos do sexo masculino selecionados através de ELISA ou intradermoreação, realizaram-se seis exames de fezes pelos métodos de Lutz/Hoffman, Pons e Janer (Lutz/HPJ e Kato/Katz e um oograma da mucosa retal, observando-se positividade em 44,7%, 47,5% e 40,1%, respectivamente. A análise comparativa dos resultados mostrou: 1 aumento da sensibilidade de ambos os métodos de exames de fezes até a terceira amostra examinada; 2 maior sensibilidade da biópsia retal quando comparada ao exame de uma única amostra fecal pelos métodos de Lutz/HPJ ou Kato/Katz; 3 igual sensibilidade pelo exame de duas a cinco amostras fecais pelo método de Kato/Katz ou duas a seis amostras pelo método de Lutz/HPJ e a biópsia retal; 4 sensibilidade superior de seis amostras fecais pelo método de Kato/Katz, quando comparado à biópsia retal; 5 igual sensibilidade entre o mesmo número de amostras examinadas pelos

  7. Influência do tempo e do meio de transporte no isolamento de fungos patogênicos de biópsias de pele Effects of time delay and transportation on isolation of pathogenic fungi from skin biopsies

    Directory of Open Access Journals (Sweden)

    Rafael Taglialegna

    2008-04-01

    Full Text Available FUNDAMENTOS: Não está definido como o meio de transporte e o intervalo de tempo até o processamento final interferem no isolamento de fungos patogênicos em material obtido de biópsias de pele. OBJETIVOS: Determinar o efeito da inoculação tardia de biópsias de pele, transportadas em diferentes meios líquidos, na taxa de isolamento de fungos patogênicos. MÉTODOS: De 47 pacientes com lesões cutâneas suspeitas de micoses invasivas obtiveram-se 278 biópsias das lesões. Cada biópsia foi transportada em frascos com caldo Sabouraud com cloranfenicol ou solução salina de cloreto de sódio e inoculada em ágar Sabouraud após 48-72 horas (precoce ou após 72 horas até sete dias (tardio, constituindo-se quatro grupos de estudo. RESULTADOS: As medianas das taxas de isolamento dos quatro grupos de esporotricose foram 100% e de paracoccidioidomicose foram 84% e 50% nos grupos precoces/solução salina ou caldo Sabouraud e 64% e 84% nos grupos tardios/solução salina ou caldo Sabouraud, respectivamente (p=0,88. Baixas taxas de contaminação resultaram em especificidade diagnóstica de 82% para doenças não fúngicas. CONCLUSÕES: Biópsias de pele podem ser transportadas em caldo Sabouraud ou solução salina por períodos de até sete dias, à temperatura ambiente, sem afetar a viabilidade dos fungos.BACKGROUND: It is not clear how culture media used during transport and the interval between the biopsy procedure and final processing can affect the successful isolation of fungi. OBJECTIVE: The aim of this study was to investigate the effects of late inoculation of skin biopsies, transported in different sterile fluids, on the isolation rate of pathogenic fungi. METHODS: A total of 278 punch biopsy specimens were collected from 47 patients with suspected lesions of invasive mycoses. Each biopsy was transported in vials with Sabouraud medium with chloramphenicol or saline solution and finally inoculated on Sabouraud agar and 2

  8. Risks incurred by hydrogen escaping from containers and conduits

    Energy Technology Data Exchange (ETDEWEB)

    Swain, M.R.; Grilliot, E.S. [Univ. of Miami, Coral Gables, FL (United States); Swain, M.N. [Analytical Technologies, Inc., Miami, FL (United States)

    1998-08-01

    This paper is a discussion of a method for hydrogen leak classification. Leaks are classified as; gas escapes into enclosed spaces, gas escapes into partially enclosed spaces (vented), and gas escapes into unenclosed spaces. Each of the three enclosure classifications is further divided into two subclasses; total volume of hydrogen escaped and flow rate of escaping hydrogen. A method to aid in risk assessment determination in partially enclosed spaces is proposed and verified for several enclosure geometries. Examples are discussed for additional enclosure geometries.

  9. Hydrogen engines based on liquid fuels, a review

    Science.gov (United States)

    Houseman, J.; Voecks, G. E.

    1981-01-01

    The concept of storing hydrogen as part of a liquid fuel, such as gasoline or methanol, and subsequent onboard generation of the hydrogen from such liquids, is reviewed. Hydrogen generation processes, such as steam reforming, partial oxidation, and thermal decomposition are evaluated in terms of theoretical potential and practical limitations, and a summary is presented on the major experimental work on conversion of gasoline and methanol. Results of experiments indicate that onboard hydrogen generation from methanol is technically feasible and will yield substantial improvements in fuel economy and emissions, especially if methanol decomposition is brought about by the use of engine exhaust heat; e.g., a methanol decomposition reactor of 3.8 provides hydrogen-rich gas for a 4 cylinder engine (1.952), and 80% of the methanol is converted, engine exhaust gas being the only heat supply. A preliminary outline of the development of a methanol-based hydrogen engine and a straight hydrogen engine is presented.

  10. A hydrogen ice cube

    NARCIS (Netherlands)

    Peters, C.J.; Schoonman, J.; Schrauwers, A.

    2004-01-01

    Hydrogen is considered to be a highly promising energy carrier. Nonetheless, before hydrogen can become the fuel of choice for the future a number of slight problems will have to be overcome. For example, how can hydrogen be safely stored? Motor vehicles running on hydrogen may be clean in concept

  11. Study of Thermodynamic Vent and Screen Baffle Integration for Orbital Storage and Transfer of Liquid Hydrogen

    Science.gov (United States)

    Cady, E. C.

    1973-01-01

    A comprehensive analytical and experimental program was performed to determine the feasibility of integrating an internal thermodynamic vent system and a full wall-screen liner for the orbital storage and transfer of liquid hydrogen (LH2). Ten screens were selected from a comprehensive screen survey. The experimental study determined the screen bubble point, flow-through pressure loss, and pressure loss along rectangular channels lined with screen on one side, for the 10 screens using LH2 saturated at 34.5 N/cm2 (50 psia). The correlated experimental data were used in an analysis to determine the optimum system characteristics in terms of minimum weight for 6 tanks ranging from 141.6 m3 (5,000 ft3) to 1.416 m3 (50 ft3) for orbital storage times of 30 and 300 days.

  12. Hyperbolic partial differential equations

    CERN Document Server

    Witten, Matthew

    1986-01-01

    Hyperbolic Partial Differential Equations III is a refereed journal issue that explores the applications, theory, and/or applied methods related to hyperbolic partial differential equations, or problems arising out of hyperbolic partial differential equations, in any area of research. This journal issue is interested in all types of articles in terms of review, mini-monograph, standard study, or short communication. Some studies presented in this journal include discretization of ideal fluid dynamics in the Eulerian representation; a Riemann problem in gas dynamics with bifurcation; periodic M

  13. Beginning partial differential equations

    CERN Document Server

    O'Neil, Peter V

    2011-01-01

    A rigorous, yet accessible, introduction to partial differential equations-updated in a valuable new edition Beginning Partial Differential Equations, Second Edition provides a comprehensive introduction to partial differential equations (PDEs) with a special focus on the significance of characteristics, solutions by Fourier series, integrals and transforms, properties and physical interpretations of solutions, and a transition to the modern function space approach to PDEs. With its breadth of coverage, this new edition continues to present a broad introduction to the field, while also addres

  14. Modeling the effects of dissolved helium pressurant on a liquid hydrogen rocket propellant tank

    Science.gov (United States)

    Richardson, I. A.; Leachman, J. W.

    2017-12-01

    A model was developed using NASA’s Generalized Fluid System Simulation Program (GFSSP) for the self-pressurization of a liquid hydrogen propellant tank due to boil-off to determine the significance of mixture non-idealities. The GFSSP model compared the tank performance for the traditional model that assumes no helium pressurant dissolves into the liquid hydrogen propellant to an updated model that accounts for dissolved helium pressurant. Traditional NASA models have been unable to account for this dissolved helium due to a lack of fundamental property information. Recent measurements of parahydrogen-helium mixtures enabled the development of the first multi-phase Equation Of State (EOS) for parahydrogen-helium mixtures. The self-pressurization GFSSP model was run assuming that the liquid propellant was pure liquid hydrogen and assuming helium dissolved into the liquid utilizing the new helium-hydrogen EOS. The analysis shows that having dissolved helium in the propellant does not have a significant effect on the tank pressurization rate for typical tank conditions (-423 °F and 30 psia).

  15. Ionic hydrogenation of organosulfur compounds

    Energy Technology Data Exchange (ETDEWEB)

    Eckert-Maksic, M.; Margetic, D. (Rudjer Boskovic Institute, Zagreb (Yugoslavia). Dept. of Organic Chemistry and Biochemistry)

    Ionic hydrogenation of the three most abundant types of organosulfur constituents of coal, aromatic sulfides, aromatic disulfides, and benzo(b)thiophene derivatives, in BF{sub 3}.H{sub 2}O-Et{sub 3}SiH is studied. Reduction of aromatic sulfides results in partial saturation of the aromatic moiety and cleavage of the corresponding SR group. Aromatic disulfides undergo quantitative sulfur-sulfur bond cleavage, while benzo(b)thiophene derivatives produce 2,3-dihydrobenzo(b)thiophenes in high yields. 32 refs., 2 figs., 3 tabs.

  16. Removing hydrogen sulphide from a gas mixture

    Energy Technology Data Exchange (ETDEWEB)

    Christy, J.G.

    1990-07-31

    This invention relates, in particular, to removing hydrogen sulfide from a gas mixture in which the molar ratio of carbon dioxide to hydrogen sulfide is very large, for example between 20 and 45. Examples of such mixtures include natural gas or gas produced by coal gasification. According to the invention, the gas mixture is contacted in a main absorber at an elevated temperature with lean and regenerable aqueous absorbent to obtain a purified gas mixture and a loaded absorbent. The loaded absorbent is introduced into a separation vessel at a reduced pressure, and flash-off gas and partially regenerated absorbent are removed from the vessel. Hydrogen sulfide is removed from the flash-off gas to obtain a lean gas, and the removed hydrogen sulfide is converted into elemental sulfur. The partially regenerated absorbent is introduced into a regenerator to obtain lean absorbent for use in the first step, and a regenerator off-gas including hydrogen sulfide. The regenerator off-gas is supplied to a sulfur recovery plant to obtain elemental sulfur and a SO{sub 2}-containing off-gas. This off-gas is treated in a converter to obtain a reduced off-gas. At least part of the lean gas obtained in a previous step is mixed with the reduced plant off-gas, and the remainder is mixed with the plant off-gas. Hydrogen sulfide is removed from the mixture of reduced off-gas and lean gas to obtain substantially hydrogen sulfide-free off-gas; the removed hydrogen sulfide is converted into elemental sulfur. The absorbent used in this process includes a chemical absorbent, such as an amine, and a physical absorbent, such as sulfolane. 1 fig.

  17. Partial knee replacement - slideshow

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/presentations/100225.htm Partial knee replacement - series—Normal anatomy To use the sharing ... A.M. Editorial team. Related MedlinePlus Health Topics Knee Replacement A.D.A.M., Inc. is accredited ...

  18. Beginning partial differential equations

    CERN Document Server

    O'Neil, Peter V

    2014-01-01

    A broad introduction to PDEs with an emphasis on specialized topics and applications occurring in a variety of fields Featuring a thoroughly revised presentation of topics, Beginning Partial Differential Equations, Third Edition provides a challenging, yet accessible,combination of techniques, applications, and introductory theory on the subjectof partial differential equations. The new edition offers nonstandard coverageon material including Burger's equation, the telegraph equation, damped wavemotion, and the use of characteristics to solve nonhomogeneous problems. The Third Edition is or

  19. Molecular Hydrogen Attenuates Neuropathic Pain in Mice

    Science.gov (United States)

    Kawaguchi, Masanori; Satoh, Yasushi; Otsubo, Yukiko; Kazama, Tomiei

    2014-01-01

    Neuropathic pain remains intractable and the development of new therapeutic strategies are urgently required. Accumulating evidence indicates that overproduction of oxidative stress is a key event in the pathogenesis of neuropathic pain. However, repeated intra-peritoneal or intrathecal injections of antioxidants are unsuitable for continuous use in therapy. Here we show a novel therapeutic method against neuropathic pain: drinking water containing molecular hydrogen (H2) as antioxidant. The effect of hydrogen on neuropathic pain was investigated using a partial sciatic nerve ligation model in mice. As indicators of neuropathic pain, temporal aspects of mechanical allodynia and thermal hyperalgesia were analysed for 3 weeks after ligation. Mechanical allodynia and thermal hyperalgesia were measured using the von Frey test and the plantar test, respectively. When mice were allowed to drink water containing hydrogen at a saturated level ad libitum after ligation, both allodynia and hyperalgesia were alleviated. These symptoms were also alleviated when hydrogen was administered only for the induction phase (from day 0 to 4 after ligation). When hydrogen was administered only for the maintenance phase (from day 4 to 21 after ligation), hyperalgesia but not allodynia was alleviated. Immunohistochemical staining for the oxidative stress marker, 4-hydroxy-2-nonenal and 8-hydroxydeoxyguanosine, showed that hydrogen administration suppressed oxidative stress induced by ligation in the spinal cord and the dorsal root ganglion. In conclusion, oral administration of hydrogen water may be useful for alleviating neuropathic pain in a clinical setting. PMID:24941001

  20. Early forest fire detection using low-energy hydrogen sensors

    Directory of Open Access Journals (Sweden)

    K. Nörthemann

    2013-11-01

    Full Text Available Most huge forest fires start in partial combustion. In the beginning of a smouldering fire, emission of hydrogen in low concentration occurs. Therefore, hydrogen can be used to detect forest fires before open flames are visible and high temperatures are generated. We have developed a hydrogen sensor comprising of a metal/solid electrolyte/insulator/semiconductor (MEIS structure which allows an economical production. Due to the low energy consumption, an autarkic working unit in the forest was established. In this contribution, first experiments are shown demonstrating the possibility to detect forest fires at a very early stage using the hydrogen sensor.

  1. Steady-state plant model to predict hydrogen levels in power plant components

    Science.gov (United States)

    Glatzmaier, Greg C.; Cable, Robert; Newmarker, Marc

    2017-06-01

    The National Renewable Energy Laboratory (NREL) and Acciona Energy North America developed a full-plant steady-state computational model that estimates levels of hydrogen in parabolic trough power plant components. The model estimated dissolved hydrogen concentrations in the circulating heat transfer fluid (HTF), and corresponding partial pressures within each component. Additionally for collector field receivers, the model estimated hydrogen pressure in the receiver annuli. The model was developed to estimate long-term equilibrium hydrogen levels in power plant components, and to predict the benefit of hydrogen mitigation strategies for commercial power plants. Specifically, the model predicted reductions in hydrogen levels within the circulating HTF that result from purging hydrogen from the power plant expansion tanks at a specified target rate. Our model predicted hydrogen partial pressures from 8.3 mbar to 9.6 mbar in the power plant components when no mitigation treatment was employed at the expansion tanks. Hydrogen pressures in the receiver annuli were 8.3 to 8.4 mbar. When hydrogen partial pressure was reduced to 0.001 mbar in the expansion tanks, hydrogen pressures in the receiver annuli fell to a range of 0.001 mbar to 0.02 mbar. When hydrogen partial pressure was reduced to 0.3 mbar in the expansion tanks, hydrogen pressures in the receiver annuli fell to a range of 0.25 mbar to 0.28 mbar. Our results show that controlling hydrogen partial pressure in the expansion tanks allows us to reduce and maintain hydrogen pressures in the receiver annuli to any practical level.

  2. Why hydrogen; Pourquoi l'hydrogene?

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-02-01

    The energy consumption increase and the associated environmental risks, led to develop new energy sources. The authors present the potentialities of the hydrogen in this context of energy supply safety. They detail the today market and the perspectives, the energy sources for the hydrogen production (fossils, nuclear and renewable), the hydrogen transport, storage, distribution and conversion, the application domains, the associated risks. (A.L.B.)

  3. Biópsia percutânea de lesões ósseas guiada por tomografia computadorizada: taxas de definição diagnóstica e complicações

    Directory of Open Access Journals (Sweden)

    Macello Jose Sampaio Maciel

    2014-10-01

    Full Text Available Objetivo: Determinar taxas de definição diagnóstica e complicações da biópsia percutânea guiada por tomografia computadorizada (TC de lesões ósseas suspeitas de malignidade. Materiais e Métodos: Estudo retrospectivo que incluiu 186 casos de biópsia percutânea guiada por TC de lesões ósseas no período de janeiro de 2010 a dezembro de 2012. Todas as amostras foram obtidas usando agulhas de 8 a 10 gauge. Foram coletados dados demográficos, história de neoplasia maligna prévia, dados relacionados à lesão, ao procedimento e ao resultado histológico. Resultados: A maioria dos pacientes era do sexo feminino (57% e a idade média foi 53,0 ± 16,4 anos. Em 139 casos (74,6% a suspeita diagnóstica era metástase e os tumores primários mais comuns foram de mama (32,1% e próstata (11,8%. Os ossos mais envolvidos foram coluna vertebral (36,0%, bacia (32,8% e ossos longos (18,3%. Houve complicações em apenas três pacientes (1,6%, incluindo uma fratura, um caso de parestesia com comprometimento funcional e uma quebra da agulha necessitando remoção cirúrgica. Amostras de 183 lesões (98,4% foram consideradas adequadas para diagnóstico. Resultados malignos foram mais frequentes nos pacientes com suspeita de lesão secundária e história de neoplasia maligna conhecida (p < 0,001 e nos procedimentos orientados pela PET/CT (p = 0,011. Conclusão: A biópsia percutânea guiada por TC é segura e eficaz no diagnóstico de lesões ósseas suspeitas.

  4. Hydrogen nanobubble at normal hydrogen electrode

    Science.gov (United States)

    Nakabayashi, S.; Shinozaki, R.; Senda, Y.; Yoshikawa, H. Y.

    2013-05-01

    Electrochemically formed hydrogen nanobubbles at a platinum rotating disk electrode (RDE) were detected by re-oxidation charge. The dissolution time course of the hydrogen nanobubbles was measured by AFM tapping topography under open-circuit conditions at stationary platinum and gold single-crystal electrodes. The bubble dissolution at platinum was much faster than that at gold because two types of diffusion, bulk and surface diffusion, proceeded at the platinum surface, whereas surface diffusion was prohibited at the gold electrode. These findings indicated that the electrochemical reaction of normal hydrogen electrode partly proceeded heterogeneously on the three-phase boundary around the hydrogen nanobubble.

  5. Hydrogen in semiconductors

    CERN Document Server

    Pankove, Jacques I

    1991-01-01

    Hydrogen plays an important role in silicon technology, having a profound effect on a wide range of properties. Thus, the study of hydrogen in semiconductors has received much attention from an interdisciplinary assortment of researchers. This sixteen-chapter volume provides a comprehensive review of the field, including a discussion of hydrogenation methods, the use of hydrogen to passivate defects, the use of hydrogen to neutralize deep levels, shallow acceptors and shallow donors in silicon, vibrational spectroscopy, and hydrogen-induced defects in silicon. In addition to this detailed cove

  6. Algebraic partial Boolean algebras

    CERN Document Server

    Smith, D

    2003-01-01

    Partial Boolean algebras, first studied by Kochen and Specker in the 1960s, provide the structure for Bell-Kochen-Specker theorems which deny the existence of non-contextual hidden variable theories. In this paper, we study partial Boolean algebras which are 'algebraic' in the sense that their elements have coordinates in an algebraic number field. Several of these algebras have been discussed recently in a debate on the validity of Bell-Kochen-Specker theorems in the context of finite precision measurements. The main result of this paper is that every algebraic finitely-generated partial Boolean algebra B(T) is finite when the underlying space H is three-dimensional, answering a question of Kochen and showing that Conway and Kochen's infinite algebraic partial Boolean algebra has minimum dimension. This result contrasts the existence of an infinite (non-algebraic) B(T) generated by eight elements in an abstract orthomodular lattice of height 3. We then initiate a study of higher-dimensional algebraic partial...

  7. Fiber optic hydrogen sensor

    Science.gov (United States)

    Buchanan, B.R.; Prather, W.S.

    1991-01-01

    Apparatus and method for detecting a chemical substance by exposing an optic fiber having a core and a cladding to the chemical substance so that the chemical substance can be adsorbed onto the surface of the cladding. The optic fiber is coiled inside a container having a pair of valves for controlling the entrance and exit of the substance. Light from a light source is received by one end of the optic fiber, preferably external to the container, and carried by the core of the fiber. Adsorbed substance changes the transmissivity of the fiber as measured by a spectrophotometer at the other end, also preferably external to the container. Hydrogen is detected by the absorption of infrared light carried by an optic fiber with a silica cladding. Since the adsorption is reversible, a sensor according to the present invention can be used repeatedly. Multiple positions in a process system can be monitored using a single container that can be connected to each location to be monitored so that a sample can be obtained for measurement, or, alternatively, containers can be placed near each position and the optic fibers carrying the partially-absorbed light can be multiplexed for rapid sequential reading, by a single spectrophotometer.

  8. Achados clínicopatológicos na tromboembolia pulmonar: estudo de 24 anos de autópsias Clinicopathological findings in pulmonary thromboembolism: a 24-year autopsy study

    Directory of Open Access Journals (Sweden)

    Hugo Hyung Bok Yoo

    2004-10-01

    Full Text Available INTRODUÇÃO: Tromboembolia pulmonar (TEP é ainda uma afecção enigmática em diversos aspectos clínicos e epidemiológicos e frequentemente erroneamente diagnosticada. OBJETIVO: Descrever a prevalência e os achados anatomopatológicos de TEP em uma série de 5261 autópsias realizadas em um hospital universitário de nível terciário, correlacionar estes achados com as doenças de base e verificar a freqüência de suspeita clínica antemortem de TEP. MÉTODO: Revisão dos registros das autópsias consecutivas realizadas de 1979 a 2002 para um estudo retrospectivo. Dos prontuários e dos relatórios de autópsias dos pacientes que tiveram TEP documentada, macro e/ou microscopicamente, foram extraídos dados demográficos, doenças de base, suspeita antemortem de TEP, localização dos trombos nos pulmões e provável local de origem da TEP. RESULTADOS: A freqüência de autópsias foi de 42,0% e TEP foi encontrada em 544 pacientes, sendo a principal causa da morte (TEP fatal em 225 casos. Doenças infecciosas (p=0,0003 foram associadas com TEP não fatal e trauma (p=0,007 com TEP fatal. A taxa de não suspeita antemortem de TEP foi 84,6% e 40,0% destes pacientes apresentaram TEP fatal. Doenças do sistema circulatório (p=0,0001, infecções (pBACKGROUND: Pulmonary thromboembolism (PTE is still an enigmatic disorder in many epidemiological and clinical features, remaining one of the most commonly misdiagnosed disorders. OBJECTIVE: To describe the prevalence and pathological findings of PTE in a series of autopsies, to correlate these findings with underlying diseases, and to verify the frequency of PTE clinically suspected before death. METHOD: The reports on 5261 consecutive autopsies performed from 1979 to 2002 in a Brazilian tertiary referral medical school were reviewed for a retrospective study. From the medical records and autopsy reports of the patients found with macroscopically and/or microscopically documented PTE, were gathered

  9. Análise da correlação entre tipos histológicos de carcinoma basocelular encontrados nas biópsias pré-operatórias e respectivas peças cirúrgicas

    OpenAIRE

    Maria Cristina de Lorenzo Messina

    2005-01-01

    O carcinoma basocelular (CBC) é tumor constituído por diferentes tipos histológicos, que demonstram diverso potencial de agressividade. Sabe-se que a correlação entre os tipos histológicos de CBC encontrados no material de biópsia pré-operatória e no material da peça cirúrgica excisional não é total. Na literatura esta correlação varia de 42,7 a 80,0% quando analisados os tipos histológicos predominantes (THP). No presente estudo foi feita análise retrospectiva de 70 casos de CBC primário sub...

  10. Biópsia transtorácica com agulha cortante (Trucut para o diagnóstico dos tumores mediastínicos Transthoracic biopsy with core cutting needle (Trucut for the diagnosis of mediastinal tumors

    Directory of Open Access Journals (Sweden)

    Mauro Zamboni

    2009-08-01

    Full Text Available Objetivo: Determinar a contribuição da biópsia percutânea com agulha cortante (Trucut no diagnóstico das massas mediastínicas. Método: Revisão retrospectiva de 56 doentes com massas mediastínicas submetidos a biópsias com agulha cortante orientadas, mas não guiadas, pela tomografia computadorizada do tórax, no período de 1999 a 2008. Resultados: A biopsia percutânea com agulha cortante forneceu material adequado para o diagnóstico em 49/56 casos, com índice de positividade de 88%. Em 7/56, o material colhido foi insuficiente para definir o diagnóstico (12%. Este método foi capaz de definir o diagnóstico em 88% dos doentes: 23/56 (41% linfomas; 12/56 (21% timomas; 5/56 (3% carcinomas tímicos; 3/56 (2% carcinoma indiferenciado de pequenas células e 1/56 (0,6% adenocarcinoma metastático, carcinoma epidermóide metastático, carcinoma neuroendócrino primitivo, plasmocitoma, teratoma, bócio. Após a biópsia, os doen tes foram submetidos a radiografia do tórax. Não houve nenhum tipo de complicação nestes doentes. Conclusão: A biópsia transtorácica com agulha cortante (Trucut orientada, mas não guiada pela tomografia computadorizada, tem alto rendimento, esclrrecendo o diagnóstico na maioria dos portadores de massas mediastínicas e pode ser útil, evitando a toracotomia exploradora, nos casos de tumores do mediastino inoperáveis ou de tratamento quimioterápico.Aim: To determine the contribution of percutaneous biopsy with core cutting needle (Trucut in the diagnosis of mediastinal tumours. Method: Retrospective review of 56 patients with mediastinal lesions who underwent percutaneous core cutting needle biopsy, oriented but not guided by computer assisted tomography of the thorax, 1999 - 2008. Results: Percutaneous biopsy with core cutting needle provided adequate material in 49/56, with a total positive sample rate of 88%. In 7/56 (12% cases the material was insufficient to define the diagnosis. Percutaneous core

  11. Partial differential equations

    CERN Document Server

    Evans, Lawrence C

    2010-01-01

    This text gives a comprehensive survey of modern techniques in the theoretical study of partial differential equations (PDEs) with particular emphasis on nonlinear equations. The exposition is divided into three parts: representation formulas for solutions; theory for linear partial differential equations; and theory for nonlinear partial differential equations. Included are complete treatments of the method of characteristics; energy methods within Sobolev spaces; regularity for second-order elliptic, parabolic, and hyperbolic equations; maximum principles; the multidimensional calculus of variations; viscosity solutions of Hamilton-Jacobi equations; shock waves and entropy criteria for conservation laws; and, much more.The author summarizes the relevant mathematics required to understand current research in PDEs, especially nonlinear PDEs. While he has reworked and simplified much of the classical theory (particularly the method of characteristics), he primarily emphasizes the modern interplay between funct...

  12. Dynamics of partial control.

    Science.gov (United States)

    Sabuco, Juan; Sanjuán, Miguel A F; Yorke, James A

    2012-12-01

    Safe sets are a basic ingredient in the strategy of partial control of chaotic systems. Recently we have found an algorithm, the sculpting algorithm, which allows us to construct them, when they exist. Here we define another type of set, an asymptotic safe set, to which trajectories are attracted asymptotically when the partial control strategy is applied. We apply all these ideas to a specific example of a Duffing oscillator showing the geometry of these sets in phase space. The software for creating all the figures appearing in this paper is available as supplementary material.

  13. Evaluacion de la biopsia transpedicular guiada por TAC Avaliação da biópsia transpedicular guiada por TC Evaluation of transpedicular percutaneous biopsy guided by CT

    Directory of Open Access Journals (Sweden)

    Luis Miguel Rosales Olivarez

    2012-09-01

    Full Text Available OBJETIVO: Valorar la utilidad de la biopsia transpedicular percutánea guiada por Tomografía Axial Computarizada en conjunto con la sistematización de estudios como pruebas diagnósticas de la etiología de la destrucción vertebral. MÉTODOS: Estudio de serie de casos prospectivo transversal de 21 pacientes a los que se les realizó biopsia transpedicular percutánea guiada por Tomografía Axial Computarizada y estudios de laboratorio y gabinete de marzo a julio del 2011, para evaluar su utilidad en el diagnóstico de destrucción vertebral. RESULTADOS: Fueron 21 pacientes, 14 hombres y 7 mujeres, con edad media de 59,2 años, cuyos niveles más afectados estuvieron en L1, L2 y L3. El reporte de la biopsia tuvo una precisión diagnóstica del 90,4%. En 2 casos se realizó correlación clínica entre biopsia y sistematización de estudios para obtener el diagnóstico. CONCLUSIÓN: La biopsia guiada por Tomografía Axial Computarizada es una técnica sencilla, útil, de bajo costo y eficaz en el estudio de la destrucción vertebral; la sistematización de estudios permite corroborar el diagnóstico de la biopsia.OBJETIVO: Avaliar a utilidade da biópsia transpedicular percutânea guiada por tomografia axial computadorizada em conjunto com a sistematização de estudos, como exames diagnósticos da etiologia da destruição vertebral. MÉTODOS: Estudo de série de casos, prospectivo e transversal de 21 pacientes submetidos à biópsia transpedicular percutânea guiada por tomografia axial computadorizada e exames laboratoriais e radiológicos, de março a julho de 2011, para avaliar sua utilidade no diagnóstico de destruição vertebral. RESULTADOS: Foram analisados 21 pacientes, 14 homens e 7 mulheres, com média de idade de 59,2 anos, cujos níveis mais afetados foram L1, L2 e L3. O laudo da biópsia teve precisão diagnóstica de 90,4%. Em dois casos, realizou-se a correlação clínica entre biópsia e sistematização de exames para obter

  14. Hydrogen separation membranes annual report for FY 2010.

    Energy Technology Data Exchange (ETDEWEB)

    Balachandran, U.; Dorris, S. E; Emerson, J. E.; Lee, T. H.; Lu, Y.; Park, C. Y.; Picciolo, J. J. (Energy Systems)

    2011-03-14

    The objective of this work is to develop dense ceramic membranes for separating hydrogen from other gaseous components in a nongalvanic mode, i.e., without using an external power supply or electrical circuitry. The goal of this project is to develop dense hydrogen transport membranes (HTMs) that nongalvanically (i.e., without electrodes or external power supply) separate hydrogen from gas mixtures at commercially significant fluxes under industrially relevant operating conditions. These membranes will be used to separate hydrogen from gas mixtures such as the product streams from coal gasification, methane partial oxidation, and water-gas shift reactions. Potential ancillary uses of HTMs include dehydrogenation and olefin production, as well as hydrogen recovery in petroleum refineries and ammonia synthesis plants, the largest current users of deliberately produced hydrogen. This report describes the results from the development and testing of HTM materials during FY 2010.

  15. Handbook of hydrogen energy

    CERN Document Server

    Sherif, SA; Stefanakos, EK; Steinfeld, Aldo

    2014-01-01

    ""This book provides an excellent overview of the hydrogen economy and a thorough and comprehensive presentation of hydrogen production and storage methods.""-Scott E. Grasman, Rochester Institute of Technology, New York, USA

  16. Center for Hydrogen Storage.

    Science.gov (United States)

    2013-06-01

    The main goals of this project were to (1) Establish a Center for Hydrogen Storage Research at Delaware State University for the preparation and characterization of selected complex metal hydrides and the determination their suitability for hydrogen ...

  17. Hydrogen production by Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Chaudhuri Surabhi

    2005-12-01

    Full Text Available Abstract The limited fossil fuel prompts the prospecting of various unconventional energy sources to take over the traditional fossil fuel energy source. In this respect the use of hydrogen gas is an attractive alternate source. Attributed by its numerous advantages including those of environmentally clean, efficiency and renew ability, hydrogen gas is considered to be one of the most desired alternate. Cyanobacteria are highly promising microorganism for hydrogen production. In comparison to the traditional ways of hydrogen production (chemical, photoelectrical, Cyanobacterial hydrogen production is commercially viable. This review highlights the basic biology of cynobacterial hydrogen production, strains involved, large-scale hydrogen production and its future prospects. While integrating the existing knowledge and technology, much future improvement and progress is to be done before hydrogen is accepted as a commercial primary energy source.

  18. Hydrogen transport membranes

    Science.gov (United States)

    Mundschau, Michael V.

    2005-05-31

    Composite hydrogen transport membranes, which are used for extraction of hydrogen from gas mixtures are provided. Methods are described for supporting metals and metal alloys which have high hydrogen permeability, but which are either too thin to be self supporting, too weak to resist differential pressures across the membrane, or which become embrittled by hydrogen. Support materials are chosen to be lattice matched to the metals and metal alloys. Preferred metals with high permeability for hydrogen include vanadium, niobium, tantalum, zirconium, palladium, and alloys thereof. Hydrogen-permeable membranes include those in which the pores of a porous support matrix are blocked by hydrogen-permeable metals and metal alloys, those in which the pores of a porous metal matrix are blocked with materials which make the membrane impervious to gases other than hydrogen, and cermets fabricated by sintering powders of metals with powders of lattice-matched ceramic.

  19. Measurement of Hydrogen Purge Rates in Parabolic Trough Receiver Tubes: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Glatzmaier, G. C.

    2010-10-01

    The purpose of this research is to investigate and develop methods to remove hydrogen centrally from commercial parabolic trough power plants. A mathematical model was developed that tracks the generation and transport of hydrogen within an operating plant. Modeling results predicted the steady-state partial pressure of hydrogen within the receiver annuli to be ~1 torr. This result agrees with measured values for the hydrogen partial pressure. The model also predicted the rate at which hydrogen must be actively removed from the expansion tank to reduce the partial pressure of hydrogen within the receiver annuli to less than 0.001 torr. Based on these results, mitigation strategies implemented at operating parabolic trough power plants can reduce hydrogen partial pressure to acceptable levels. Transient modeling predicted the time required to reduce the hydrogen partial pressures within receiver annuli to acceptable levels. The times were estimated as a function of bellows temperature, getter quantity, and getter temperature. This work also includes an experimental effort that will determine the time required to purge hydrogen from a receiver annulus with no getter.

  20. Solar hydrogen generator

    Science.gov (United States)

    Sebacher, D. I.; Sabol, A. P. (Inventor)

    1977-01-01

    An apparatus, using solar energy to manufacture hydrogen by dissociating water molecules into hydrogen and oxygen molecules is described. Solar energy is concentrated on a globe containing water thereby heating the water to its dissociation temperature. The globe is pervious to hydrogen molecules permitting them to pass through the globe while being essentially impervious to oxygen molecules. The hydrogen molecules are collected after passing through the globe and the oxygen molecules are removed from the globe.

  1. Hydrogen Technologies Safety Guide

    Energy Technology Data Exchange (ETDEWEB)

    Rivkin, C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Burgess, R. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Buttner, W. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-01-01

    The purpose of this guide is to provide basic background information on hydrogen technologies. It is intended to provide project developers, code officials, and other interested parties the background information to be able to put hydrogen safety in context. For example, code officials reviewing permit applications for hydrogen projects will get an understanding of the industrial history of hydrogen, basic safety concerns, and safety requirements.

  2. Magnesium for Hydrogen Storage

    DEFF Research Database (Denmark)

    Vigeholm, B.; Kjøller, John; Larsen, Bent

    1980-01-01

    The reaction of hydrogen with commercially pure magnesium powder (above 99.7%) was investigated in the temperature range 250–400 °C. Hydrogen is readily sorbed above the dissociation pressure. During the initial exposure the magnesium powder sorbs hydrogen slowly below 400 °C but during the second...

  3. Biological hydrogen photoproduction

    Energy Technology Data Exchange (ETDEWEB)

    Nemoto, Y. [Univ. of Miami, FL (United States)

    1995-09-01

    Following are the major accomplishments of the 6th year`s study of biological hydrogen photoproduction which were supported by DOE/NREL. (1) We have been characterizing a biological hydrogen production system using synchronously growing aerobically nitrogen-fixing unicellular cyanobacterium, Synechococcus sp. Miami BG 043511. So far it was necessary to irradiate the cells to produce hydrogen. Under darkness they did not produce hydrogen. However, we found that, if the cells are incubated with oxygen, they produce hydrogen under the dark. Under 80% argon + 20% oxygen condition, the hydrogen production activity under the dark was about one third of that under the light + argon condition. (2) Also it was necessary so far to incubate the cells under argon atmosphere to produce hydrogen in this system. Argon treatment is very expensive and should be avoided in an actual hydrogen production system. We found that, if the cells are incubated at a high cell density and in a container with minimum headspace, it is not necessary to use argon for the hydrogen production. (3) Calcium ion was found to play an important role in the mechanisms of protection of nitrogenase from external oxygen. This will be a clue to understand the reason why the hydrogen production is so resistant to oxygen in this strain. (4) In this strain, sulfide can be used as electron donor for the hydrogen production. This result shows that waste water can be used for the hydrogen production system using this strain.

  4. Fundamental partial compositeness

    DEFF Research Database (Denmark)

    Sannino, Francesco; Strumia, Alessandro; Tesi, Andrea

    2016-01-01

    We construct renormalizable Standard Model extensions, valid up to the Planck scale, that give a composite Higgs from a new fundamental strong force acting on fermions and scalars. Yukawa interactions of these particles with Standard Model fermions realize the partial compositeness scenario. Unde...

  5. Partially ordered models

    NARCIS (Netherlands)

    Fernandez, R.; Deveaux, V.

    2010-01-01

    We provide a formal definition and study the basic properties of partially ordered chains (POC). These systems were proposed to model textures in image processing and to represent independence relations between random variables in statistics (in the later case they are known as Bayesian networks).

  6. Partial Biotinidase Deficiency

    OpenAIRE

    J Gordon Millichap

    1990-01-01

    The symptoms, biochemical features and inheritance pattern of partial biotinidase deficiency have been studied at the Departments of Human Genetics and Pediatrics, Medical College of Virginia, Richmond, VA; the State Laboratory Institute, Massachusetts Department of Public Health; Massachusetts General Hospital, Boston; the Lincoln Clinic, NB; and the Division of Human Genetics, university of Maryland School of Medicine, Baltimore.

  7. Partial gravity habitat study

    Science.gov (United States)

    Capps, Stephen; Lorandos, Jason; Akhidime, Eval; Bunch, Michael; Lund, Denise; Moore, Nathan; Murakawa, Kiosuke

    1989-01-01

    The purpose of this study is to investigate comprehensive design requirements associated with designing habitats for humans in a partial gravity environment, then to apply them to a lunar base design. Other potential sites for application include planetary surfaces such as Mars, variable-gravity research facilities, and a rotating spacecraft. Design requirements for partial gravity environments include locomotion changes in less than normal earth gravity; facility design issues, such as interior configuration, module diameter, and geometry; and volumetric requirements based on the previous as well as psychological issues involved in prolonged isolation. For application to a lunar base, it is necessary to study the exterior architecture and configuration to insure optimum circulation patterns while providing dual egress; radiation protection issues are addressed to provide a safe and healthy environment for the crew; and finally, the overall site is studied to locate all associated facilities in context with the habitat. Mission planning is not the purpose of this study; therefore, a Lockheed scenario is used as an outline for the lunar base application, which is then modified to meet the project needs. The goal of this report is to formulate facts on human reactions to partial gravity environments, derive design requirements based on these facts, and apply the requirements to a partial gravity situation which, for this study, was a lunar base.

  8. Partially Hidden Markov Models

    DEFF Research Database (Denmark)

    Forchhammer, Søren Otto; Rissanen, Jorma

    1996-01-01

    Partially Hidden Markov Models (PHMM) are introduced. They differ from the ordinary HMM's in that both the transition probabilities of the hidden states and the output probabilities are conditioned on past observations. As an illustration they are applied to black and white image compression wher...

  9. Honesty in partial logic

    NARCIS (Netherlands)

    W. van der Hoek (Wiebe); J.O.M. Jaspars; E. Thijsse

    1995-01-01

    textabstractWe propose an epistemic logic in which knowledge is fully introspective and implies truth, although truth need not imply epistemic possibility. The logic is presented in sequential format and is interpreted in a natural class of partial models, called balloon models. We examine the

  10. Partial Remission Definition

    DEFF Research Database (Denmark)

    Andersen, Marie Louise Max; Hougaard, Philip; Pörksen, Sven

    2014-01-01

    OBJECTIVE: To validate the partial remission (PR) definition based on insulin dose-adjusted HbA1c (IDAA1c). SUBJECTS AND METHODS: The IDAA1c was developed using data in 251 children from the European Hvidoere cohort. For validation, 129 children from a Danish cohort were followed from the onset...

  11. Hydrogen separation process

    Science.gov (United States)

    Mundschau, Michael [Longmont, CO; Xie, Xiaobing [Foster City, CA; Evenson, IV, Carl; Grimmer, Paul [Longmont, CO; Wright, Harold [Longmont, CO

    2011-05-24

    A method for separating a hydrogen-rich product stream from a feed stream comprising hydrogen and at least one carbon-containing gas, comprising feeding the feed stream, at an inlet pressure greater than atmospheric pressure and a temperature greater than 200.degree. C., to a hydrogen separation membrane system comprising a membrane that is selectively permeable to hydrogen, and producing a hydrogen-rich permeate product stream on the permeate side of the membrane and a carbon dioxide-rich product raffinate stream on the raffinate side of the membrane. A method for separating a hydrogen-rich product stream from a feed stream comprising hydrogen and at least one carbon-containing gas, comprising feeding the feed stream, at an inlet pressure greater than atmospheric pressure and a temperature greater than 200.degree. C., to an integrated water gas shift/hydrogen separation membrane system wherein the hydrogen separation membrane system comprises a membrane that is selectively permeable to hydrogen, and producing a hydrogen-rich permeate product stream on the permeate side of the membrane and a carbon dioxide-rich product raffinate stream on the raffinate side of the membrane. A method for pretreating a membrane, comprising: heating the membrane to a desired operating temperature and desired feed pressure in a flow of inert gas for a sufficient time to cause the membrane to mechanically deform; decreasing the feed pressure to approximately ambient pressure; and optionally, flowing an oxidizing agent across the membrane before, during, or after deformation of the membrane. A method of supporting a hydrogen separation membrane system comprising selecting a hydrogen separation membrane system comprising one or more catalyst outer layers deposited on a hydrogen transport membrane layer and sealing the hydrogen separation membrane system to a porous support.

  12. Safe venting of hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, W.F.; Dewart, J.M.; Edeskuty, F.J.

    1990-01-01

    The disposal of hydrogen is often required in the operation of an experimental facility that contains hydrogen. Whether the vented hydrogen can be discharged to the atmosphere safely depends upon a number of factors such as the flow rate and atmospheric conditions. Calculations have been made that predict the distance a combustible mixture can extend from the point of release under some specified atmospheric conditions. Also the quantity of hydrogen in the combustible cloud is estimated. These results can be helpful in deciding of the hydrogen can be released directly to the atmosphere, or if it must be intentionally ignited. 15 refs., 5 figs., 2 tabs.

  13. Hydrogen energy for beginners

    CERN Document Server

    2013-01-01

    This book highlights the outstanding role of hydrogen in energy processes, where it is the most functional element due to its unique peculiarities that are highlighted and emphasized in the book. The first half of the book covers the great natural hydrogen processes in biology, chemistry, and physics, showing that hydrogen is a trend that can unite all natural sciences. The second half of the book is devoted to the technological hydrogen processes that are under research and development with the aim to create the infrastructure for hydrogen energetics. The book describes the main features of hydrogen that make it inalienable player in processes such as fusion, photosynthesis, and metabolism. It also covers the methods of hydrogen production and storage, highlighting at the same time the exclusive importance of nanotechnologies in those processes.

  14. Cyclooctanaminium hydrogen succinate monohydrate

    Directory of Open Access Journals (Sweden)

    Sanaz Khorasani

    2012-04-01

    Full Text Available In the title hydrated salt, C8H18N+·C4H5O4−·H2O, the cyclooctyl ring of the cation is disordered over two positions in a 0.833 (3:0.167 (3 ratio. The structure contains various O—H.·O and N—H...O interactions, forming a hydrogen-bonded layer of molecules perpendicular to the c axis. In each layer, the ammonium cation hydrogen bonds to two hydrogen succinate anions and one water molecule. Each hydrogen succinate anion hydrogen bonds to neighbouring anions, forming a chain of molecules along the b axis. In addition, each hydrogen succinate anion hydrogen bonds to two water molecules and the ammonium cation.

  15. Proton conducting ceramic membranes for hydrogen separation

    Energy Technology Data Exchange (ETDEWEB)

    Elangovan, S [South Jordan, UT; Nair, Balakrishnan G [Sandy, UT; Small, Troy [Midvale, UT; Heck, Brian [Salt Lake City, UT

    2011-09-06

    A multi-phase proton conducting material comprising a proton-conducting ceramic phase and a stabilizing ceramic phase. Under the presence of a partial pressure gradient of hydrogen across the membrane or under the influence of an electrical potential, a membrane fabricated with this material selectively transports hydrogen ions through the proton conducting phase, which results in ultrahigh purity hydrogen permeation through the membrane. The stabilizing ceramic phase may be substantially structurally and chemically identical to at least one product of a reaction between the proton conducting phase and at least one expected gas under operating conditions of a membrane fabricated using the material. In a barium cerate-based proton conducting membrane, one stabilizing phase is ceria.

  16. Hydrogen isotopic substitution experiments in nanostructured porous silicon

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, W.D. [Facultad de Ciencias Exactas y Naturales y Agrimensura - (UNNE), Avenida Libertad 5500, 3400 Corrientes (Argentina); Koropecki, R.R. [INTEC (CONICET-UNL), Gueemes 3450, 3000 Santa Fe (Argentina)], E-mail: rkoro@intec.ceride.gov.ar; Arce, R.D. [INTEC (CONICET-UNL), Gueemes 3450, 3000 Santa Fe (Argentina); Busso, A. [Facultad de Ciencias Exactas y Naturales y Agrimensura - (UNNE), Avenida Libertad 5500, 3400 Corrientes (Argentina)

    2008-04-30

    Nanostructured porous silicon is usually prepared by electrochemical anodization of monocrystalline silicon using a fluorine-rich electrolyte. As a result of this process, the silicon atoms conserve their original crystalline location, and many of the dangling bonds appearing on the surface of the nanostructure are saturated by hydrogen coming from the electrolyte. This work presents an IR study of the effects produced by partial substitution of water in the electrolytic solution by deuterium oxide. The isotopic effects on the IR spectra are analyzed for the as-prepared samples and for the samples subjected to partial thermal effusion of hydrogen and deuterium. We demonstrate that, although deuterium is chemically indistinguishable from hydrogen, it presents a singular behaviour when used in porous silicon preparation. We found that deuterium preferentially bonds forming Si-DH groups. A possible explanation of the phenomenon is presented, based on the different diffusivities of hydrogen and deuterium.

  17. Partially composite Higgs models

    DEFF Research Database (Denmark)

    Alanne, Tommi; Buarque Franzosi, Diogo; Frandsen, Mads T.

    2018-01-01

    constraints. A small part of parameter space around the classically conformal limit is stable up to the Planck scale. This is however already strongly disfavored by LHC results. in different limits, the models realize both (partially) composite-Higgs and (bosonic) technicolor models and a dynamical extension......We study the phenomenology of partially composite-Higgs models where electroweak symmetry breaking is dynamically induced, and the Higgs is a mixture of a composite and an elementary state. The models considered have explicit realizations in terms of gauge-Yukawa theories with new strongly...... interacting fermions coupled to elementary scalars and allow for a very SM-like Higgs state. We study constraints on their parameter spaces from vacuum stability and perturbativity as well as from LHC results and find that requiring vacuum stability up to the compositeness scale already imposes relevant...

  18. Arthroscopic partial medial meniscectomy

    Directory of Open Access Journals (Sweden)

    Dašić Žarko

    2011-01-01

    Full Text Available Background/Aim. Meniscal injuries are common in professional or recreational sports as well as in daily activities. If meniscal lesions lead to physical impairment they usually require surgical treatment. Arthroscopic treatment of meniscal injuries is one of the most often performed orthopedic operative procedures. Methods. The study analyzed the results of arthroscopic partial medial meniscectomy in 213 patients in a 24-month period, from 2006, to 2008. Results. In our series of arthroscopically treated medial meniscus tears we noted 78 (36.62% vertical complete bucket handle lesions, 19 (8.92% vertical incomplete lesions, 18 (8.45% longitudinal tears, 35 (16.43% oblique tears, 18 (8.45% complex degenerative lesions, 17 (7.98% radial lesions and 28 (13.14% horisontal lesions. Mean preoperative International Knee Documentation Committee (IKDC score was 49.81%, 1 month after the arthroscopic partial medial meniscectomy the mean IKDC score was 84.08%, and 6 months after mean IKDC score was 90.36%. Six months after the procedure 197 (92.49% of patients had good or excellent subjective postoperative clinical outcomes, while 14 (6.57% patients subjectively did not notice a significant improvement after the intervention, and 2 (0.93% patients had no subjective improvement after the partial medial meniscectomy at all. Conclusion. Arthroscopic partial medial meniscetomy is minimally invasive diagnostic and therapeutic procedure and in well selected cases is a method of choice for treatment of medial meniscus injuries when repair techniques are not a viable option. It has small rate of complications, low morbidity and fast rehabilitation.

  19. Mergers by Partial Acquisition

    OpenAIRE

    Lindqvist, Tobias

    2004-01-01

    This paper evaluates partial acquisition strategies. The model allows for buying a share of a firm before the actual acquisition takes place. Holding a share in a competing firm before the acquisition of another firm, outsider-toehold, eliminates the insiders' dilemma, i.e. profitable mergers do not occur. This strategy may thus be more profitable for a buyer than acquiring entire firms at once. Furthermore, the insiders' dilemma arises from the assumption of a positive externality on the out...

  20. Hydrogen storage methods

    Science.gov (United States)

    Züttel, Andreas

    Hydrogen exhibits the highest heating value per mass of all chemical fuels. Furthermore, hydrogen is regenerative and environmentally friendly. There are two reasons why hydrogen is not the major fuel of today's energy consumption. First of all, hydrogen is just an energy carrier. And, although it is the most abundant element in the universe, it has to be produced, since on earth it only occurs in the form of water and hydrocarbons. This implies that we have to pay for the energy, which results in a difficult economic dilemma because ever since the industrial revolution we have become used to consuming energy for free. The second difficulty with hydrogen as an energy carrier is its low critical temperature of 33 K (i.e. hydrogen is a gas at ambient temperature). For mobile and in many cases also for stationary applications the volumetric and gravimetric density of hydrogen in a storage material is crucial. Hydrogen can be stored using six different methods and phenomena: (1) high-pressure gas cylinders (up to 800 bar), (2) liquid hydrogen in cryogenic tanks (at 21 K), (3) adsorbed hydrogen on materials with a large specific surface area (at Tchemically bonded in covalent and ionic compounds (at ambient pressure), or (6) through oxidation of reactive metals, e.g. Li, Na, Mg, Al, Zn with water. The most common storage systems are high-pressure gas cylinders with a maximum pressure of 20 MPa (200 bar). New lightweight composite cylinders have been developed which are able to withstand pressures up to 80 MPa (800 bar) and therefore the hydrogen gas can reach a volumetric density of 36 kg.m-3, approximately half as much as in its liquid state. Liquid hydrogen is stored in cryogenic tanks at 21.2 K and ambient pressure. Due to the low critical temperature of hydrogen (33 K), liquid hydrogen can only be stored in open systems. The volumetric density of liquid hydrogen is 70.8 kg.m-3, and large volumes, where the thermal losses are small, can cause hydrogen to reach a

  1. Dynamics of hydrogen in hydrogenated amorphous silicon

    Indian Academy of Sciences (India)

    bonding configuration due to hydrogen migration have been proposed as a mechanism of defect generation in a-Si:H [6,7]. Thus hydrogen plays a dual role in a-Si:H: (1) acting as a .... the sphere of radius R0 and allows to express. ∆F as a function of localization radius R0. Using eqs (10) and (11), the volume integration.

  2. Precision spectroscopy on atomic hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Parthey, Christian Godehard

    2011-12-15

    This Thesis reports on three measurements involving the 1S-2S transition in atomic hydrogen and deuterium conducted on a 5.8 K atomic beam. The transition is excited Doppler-free via two counter-propagating photons near 243 nm. The H/D isotope shift has been determined as {delta}{integral}{sub exp}=670 994 334 606(15) Hz. Comparing with the theoretical value for the isotope shift, excluding the leading nuclear size effect, {delta}{integral}{sub th}=670 999 566.90(66)(60) kHz we confirm, twice more accurate, the rms charge radius difference of the deuteron and the proton as left angle r{sup 2} right angle {sub d}- left angle r{sup 2} right angle {sub p}=3.82007(65) fm{sup 2} and the deuteron structure radius r{sub str}=1.97507(78) fm. The frequency ratio of the 1S-2S transition in atomic hydrogen to the cesium ground state hyperfine transition provided by the mobile cesium fountain clock FOM is measured to be {integral}{sub 1S-2S}=2 466 061 413 187 035 (10) Hz which presents a fractional frequency uncertainty of 4.2 x 10{sup -15}. The second absolute frequency measurement of the 1S-2S transition in atomic hydrogen presents the first application of a 900 km fiber link between MPQ and Physikalisch- Technische Bundesanstalt (PTB) in Braunschweig which we have used to calibrate the MPQ hydrogen maser with the stationary cesium fountain clock CSF1 at PTB. With the result of {integral}{sub 1S-2S}=2 466 061 413 187 017 (11) Hz we can put a constraint on the electron Lorentz boost violating coefficients 0.95c{sub (TX)}-0.29c{sub (TY)}-0.08 c{sub (TZ)}=(2.2{+-}1.8) x 10{sup -11} within the framework of minimal standard model extensions. We limit a possible drift of the strong coupling constant through the ratio of magnetic moments at a competitive level ({partial_derivative})/({partial_derivative}t)ln ({mu}{sub Cs})/({mu}{sub B})=-(3.0{+-}1.2) x 10{sup -15} yr{sup -1}.

  3. Thermodynamic driving force of hydrogen on rumen microbial metabolism

    OpenAIRE

    Lingen, Van, Henk J.; Plugge, Caroline M.; Fadel, James G.; Kebreab,Ermias; Bannink, André; Dijkstra, Jan

    2016-01-01

    Hydrogen is a key product of rumen fermentation and has been suggested to thermodynamically control the production of the various volatile fatty acids (VFA). Previous studies, however, have not accounted for the fact that only thermodynamic near-equilibrium conditions control the magnitude of reaction rate. Furthermore, the role of NAD, which is affected by hydrogen partial pressure (PH 2), has often not been considered. The aim of this study was to quantify the control of PH 2 on reaction ra...

  4. Engineering analyses and design calculations of NASA, Langley Research Center hydrogen-air-vitiated heater with oxygen replenishment

    Science.gov (United States)

    1973-01-01

    The technical basis is presented for the design of the hydrogen-air-vitiated heater. The heater liner is subjected to a maximum thermal environment at a specified condition, where the combustion gas temperature, pressure and flow rate are 5000 F, 750 psia, and 11.0 lb/sec, respectively, and results in a heat flux of the order of 275 BTU/sec-sq ft. Cooling and stress analyses indicate that water is the logical choice for cooling of the combustor liner. A mixing analysis was undertaken to establish a good combination of combustor length and injector configuration. The analysis, using a conservative analytical approach, indicates a combustor length of the order of 5 ft combined with discrete fuel and oxidizer injection at an approximate 2-1/2 inch radial combustor position, and results in uniform combustion products at the heater exit for all specified envelope conditions.

  5. Hydrogen Filling Station

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Robert F; Sabacky, Bruce; Anderson II, Everett B; Haberman, David; Al-Hassin, Mowafak; He, Xiaoming; Morriseau, Brian

    2010-02-24

    Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. The Freedom CAR and Freedom FUEL initiatives emphasize the importance of hydrogen as a future transportation fuel. Presently, Las Vegas has one hydrogen fueling station powered by natural gas. However, the use of traditional sources of energy to produce hydrogen does not maximize the benefit. The hydrogen fueling station developed under this grant used electrolysis units and solar energy to produce hydrogen fuel. Water and electricity are furnished to the unit and the output is hydrogen and oxygen. Three vehicles were converted to utilize the hydrogen produced at the station. The vehicles were all equipped with different types of technologies. The vehicles were used in the day-to-day operation of the Las Vegas Valley Water District and monitoring was performed on efficiency, reliability and maintenance requirements. The research and demonstration utilized for the reconfiguration of these vehicles could lead to new technologies in vehicle development that could make hydrogen-fueled vehicles more cost effective, economical, efficient and more widely used. In order to advance the development of a hydrogen future in Southern Nevada, project partners recognized a need to bring various entities involved in hydrogen development and deployment together as a means of sharing knowledge and eliminating duplication of efforts. A road-mapping session was held in Las Vegas in June 2006. The Nevada State Energy Office, representatives from DOE, DOE contractors and LANL, NETL, NREL were present. Leadership from the National hydrogen Association Board of Directors also attended. As a result of this session, a roadmap for hydrogen development was created. This roadmap has the ability to become a tool for use by other road-mapping efforts in the hydrogen community. It could also become a standard template for other states or even countries to approach planning for a hydrogen

  6. Hydrogen energy systems studies

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.M.; Steinbugler, M.; Kreutz, T. [Princeton Univ., NJ (United States). Center for Energy and Environmental Studies

    1998-08-01

    In this progress report (covering the period May 1997--May 1998), the authors summarize results from ongoing technical and economic assessments of hydrogen energy systems. Generally, the goal of their research is to illuminate possible pathways leading from present hydrogen markets and technologies toward wide scale use of hydrogen as an energy carrier, highlighting important technologies for RD and D. Over the past year they worked on three projects. From May 1997--November 1997, the authors completed an assessment of hydrogen as a fuel for fuel cell vehicles, as compared to methanol and gasoline. Two other studies were begun in November 1997 and are scheduled for completion in September 1998. The authors are carrying out an assessment of potential supplies and demands for hydrogen energy in the New York City/New Jersey area. The goal of this study is to provide useful data and suggest possible implementation strategies for the New York City/ New Jersey area, as the Hydrogen Program plans demonstrations of hydrogen vehicles and refueling infrastructure. The authors are assessing the implications of CO{sub 2} sequestration for hydrogen energy systems. The goals of this work are (a) to understand the implications of CO{sub 2} sequestration for hydrogen energy system design; (b) to understand the conditions under which CO{sub 2} sequestration might become economically viable; and (c) to understand design issues for future low-CO{sub 2} emitting hydrogen energy systems based on fossil fuels.

  7. Prevalência de coilocitose em biópsias penianas de parceiros de mulheres com lesões genitais induzidas pelo HPV Prevalence of koilocytosis in penile biopsies of partners of women with HPV-induced genital lesions

    Directory of Open Access Journals (Sweden)

    Alberto Azoubel Antunes

    2004-01-01

    Full Text Available OBJETIVO: determinar a prevalência de coilocitose em biópsias penianas de parceiros de mulheres com lesões genitais induzidas pelo HPV e analisar os fatores de risco envolvidos com a infecção peniana. MÉTODOS: foram incluídos neste estudo de coorte transversal 80 parceiros de mulheres com lesões induzidas pelo HPV no período de maio de 2002 a junho de 2003. A média de idade dos pacientes foi de 34,1 anos (variando de 16 a 63. Todos os pacientes negavam ou desconheciam qualquer tipo de lesão genital. Foram submetidos à anamnese específica quanto a presença de sintomas uretrais, passado de doenças sexualmente transmissíveis (DST, número de parceiras sexuais, uso de preservativos e postectomia. Posteriormente foram submetidos à peniscopia com a utilização de soluções de ácido acético e azul de toluidina, tendo sido colhido material para biópsia das lesões de aspecto morfológico sugestivo de contaminação por HPV. A análise estatística foi realizada pelo teste do chi2. RESULTADOS: o exame foi considerado negativo em 24 pacientes (30%. Todos os outros 56 pacientes (70% apresentaram lesões acetobrancas e azul de toluidina positivas. Destes, 53 foram biopsiados, e 41 pacientes (77,3% apresentaram biópsia com alterações histológicas sugestivas de infecção pelo HPV. CONCLUSÕES: a prevalência da infecção genital masculina pelo HPV foi de 51,2%, e nenhum fator de risco analisado foi associado com uma maior prevalência da infecção genital pelo vírus.PURPOSE: to determine the prevalence of koilocytosis in penile biopsies of partners of women with HPV-induced genital lesions, and to analyze the risk factors associated with the penile viral infection. METHODS: a total of 80 partners of HPV-infected women with genital lesions were included in this transversal cohort study. The study was carried out between May 2002 and June 2003. The mean age was 34.1 years (16 to 63. No patient reported any kind of genital lesion

  8. Biópsia pulmonar incisional por toracoscopia paraxifoide transdiafragmática com dois portais em cães Pulmonary incisional biopsy by means of transdiaphragmatic paraxiphoid thoracoscopy with two ports in dog

    Directory of Open Access Journals (Sweden)

    Paula C. Basso

    2010-07-01

    Full Text Available As doenças respiratórias observadas na clínica médica de pequenos animais são numerosas, assim como as possibilidades diagnósticas, dentre as quais encontram-se os exames laboratoriais, os estudos radiográficos, os lavados broncoalveolares e as biópsias. Na presente pesquisa avaliaram-se os resultados da toracoscopia paraxifoide transdiafragmática para a realização de biópsia pulmonar em cães, sendo utilizados para tanto, 13 animais clinicamente sadios. Sob anestesia geral, produziu-se pneumotórax no volume de 30ml kg-1 de ar ambiente para cada hemitórax. O acesso foi obtido a partir de dois trocartes, posicionados entre o apêndice xifoide e o arco costal, os quais transfixaram o diafragma. O primeiro portal foi empregado para a passagem do endoscópio e o segundo para a utilização de pinça saca-bocado, empregada na obtenção de biópsia. Em seguida, a pinça foi removida e um dreno torácico foi posicionado através do portal. Durante os procedimentos, aferiram-se as frequências respiratória e cardíaca, a saturação de oxigênio, as pressões arterial média e venosa central e os parâmetros hemogasométricos. Os drenos foram removidos num período de até 48 horas de pós-operatório, verificando-se mínima produção de ar e/ou líquido. Concluiu-se se tratar de uma técnica rápida, segura e sem complicações trans e pós-operatórias, permitindo aquisição de material suficiente para a avaliação histológica do pulmão.There are many respiratory diseases in small animals, as well as the possibilities of diagnoses, as laboratory and radiographic exams, bronchoalveolar lavage and biopsies. This research aimed at assessing the results of transdiaphragmatic paraxiphoid thoracoscopies in pulmonary biopsies of thirteen clinically healthy dogs. Under general anesthesia, each dog was insufflated with 30ml kg-1 of air in each hemithorax; two trocars were placed between the xiphoid appendix and the costal arch through the

  9. Perfil Epidemiológico de Pacientes Submetidos à Biópsia Gástrica em um Hospital Escola do Sul de Minas Gerais/ Epidemiological Profile of Patients Undergo Gastric Biopsy in a School Hospital of Minas Gerais

    Directory of Open Access Journals (Sweden)

    Isabela Maria A. Ribeiro Simões

    2014-09-01

    Full Text Available Objetivo: Determinar a prevalência de lesões benignas e neoplasia gástrica através do estudo de biópsias realizadas em um Hospital Escola do Sul de Minas Gerais, no período entre 2007 e 2011. Materiais e Métodos: A pesquisa documental foi quantitativa e retrospectiva, baseada na análise dos registros de biópsias e prontuários. Realizou-se o levantamento de dados referentes à idade, gênero, cor, profissão, diagnóstico histopatológico e presença de Helicobacter pylori nas amostras. Resultados: O número total de biópsias gástricas analisadas foi de 1225, cujo perfil populacional encontrado foi: idade média de 56,75 anos, sexo masculino (52%, cor branca (81,9 %, aposentado (30%. Os diagnósticos mais frequentes foram: gastrites (71,9%, pólipos (14,2%, adenocarcinomas (5,9%, úlceras gástricas (6%, linfomas (0,4%, sem alterações (0,4% e outros (1,2%. Em outros, encontram-se achados de malignidade, metaplasia e xantelasma gástrico. Em relação à presença de Helicobacter pylori nas amostras, o resultado encontrado foi de24% positivas, 46% negativas e 30% não pesquisadas. Conclusão: Os resultados confirmam a alta frequência das doenças gástricas e sua incidência nas diversas faixas etárias, além do envolvimento do H. pylori em tais afecções. É de grande importância a caracterização dos dados epidemiológicos, o que permite prováveis direcionamentos para programas de prevenção e informação para a população. Objective: To determine the prevalence of benign lesions and gastric cancer through study of biopsies performed at a school hospital in southern Minas Gerais, in the period between 2007 and 2011.Materials and Methods: The research was quantitative and retrospective, based on analysis of biopsies records and medical records. We conducted the survey data regarding age, sex, color, profession, histopathological diagnosis and the presence of Helicobacter pylori in the samples. Results: The total number of

  10. Allylammonium hydrogen oxalate hemihydrate

    Directory of Open Access Journals (Sweden)

    Błażej Dziuk

    2014-08-01

    Full Text Available In the title hydrated molecular salt, C3H8N+·C2HO4−·0.5H2O, the water O atom lies on a crystallographic twofold axis. The C=C—C—N torsion angle in the cation is 2.8 (3° and the dihedral angle between the CO2 and CO2H planes in the anion is 1.0 (4°. In the crystal, the hydrogen oxalate ions are linked by O—H...O hydrogen bonds, generating [010] chains. The allylammonium cations bond to the chains through N—H...O and N—H...(O,O hydrogen bonds. The water molecule accepts two N—H...O hydrogen bonds and makes two O—H...O hydrogen bonds. Together, the hydrogen bonds generate (100 sheets.

  11. Hydrogen Fuelling Stations

    DEFF Research Database (Denmark)

    Rothuizen, Erasmus Damgaard

    This thesis concerns hydrogen fuelling stations from an overall system perspective. The study investigates thermodynamics and energy consumption of hydrogen fuelling stations for fuelling vehicles for personal transportation. For the study a library concerning the components in a hydrogen fuelling...... station has been developed in Dymola. The models include the fuelling protocol (J2601) for hydrogen vehicles made by Society of Automotive Engineers (SAE) and the thermodynamic property library CoolProp is used for retrieving state point. The components in the hydrogen fuelling library are building up....... A system consisting of one high pressure storage tank is used to investigate the thermodynamics of fuelling a hydrogen vehicle. The results show that the decisive parameter for how the fuelling proceeds is the pressure loss in the vehicle. The single tank fuelling system is compared to a cascade fuelling...

  12. Autópsias psicológicas sobre suicídio de idosos no Rio de Janeiro Psychogical autopsies into suicide among the elderly in Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Maria Cecília de Souza Minayo

    2012-10-01

    Full Text Available Esse estudo analisa autópsias psicológicas e contextualiza problemas e fatores que levaram algumas pessoas idosas a acabar com a própria vida na cidade do Rio de Janeiro, entre 2004 e 2007. O estudo parte de 26 laudos periciais de homens e mulheres que cometeram suicídios no centro, na zona norte e na zona sul da cidade. As famílias desses idosos foram contatadas por carta e telefone e depois, pessoalmente. Foram oito autópsias psicológicas, por meio das quais foram coletados dados de identificação, genograma da família e uma entrevista que reconstituiu o modo de vida e as razões da violência autoinfligida. Os entrevistados foram familiares, amigos e conhecidos das vítimas. Os suicídios estão associados a depressão, a enfermidades físicas e mentais graves e a fatores socioculturais como decadência profissional e socioeconômica. Esses eventos ocorreram com e sem apoio familiar, com e sem acompanhamento médico. A fragilização cumulativa de recursos pessoais e sociais no ciclo vital revela que o risco do suicídio em idosos exige cuidados permanentes de saúde pública.This study analyses psychological autopsies and contextualizes problems and issues that led to elderly people taking their own lives in the city of Rio de Janeiro between 2004 and 2007. The study began with an analysis of 26 expert findings of elderly men and women who committed suicide in the central, northern and southern areas of Rio de Janeiro. The sample was contacted by letter and telephone and after that, by a one-on-one conversation. Eight psychological autopsies were conducted, in which identification data and family genograms were collected followed by an interview to profile the life style and the reasons for the self-inflicted violence. The interviewees were family members, friends and acquaintances of the victims. The suicides are associated with depression, serious physical and mental illness, as well as socio-cultural factors related to

  13. Biópsia percutânea por agulha grossa de tumores de partes moles guiada por tomografia computadorizada: resultados e correlação com análise da peça cirúrgica

    Directory of Open Access Journals (Sweden)

    Rubens Chojniak

    2012-10-01

    Full Text Available OBJETIVO: Avaliar a eficácia da biópsia percutânea por agulha grossa (BPAG de tumores de partes moles guiada por tomografia computadorizada (TC, em relação ao sucesso na obtenção de amostra para análise, e comparar o diagnóstico da BPAG com o resultado anatomopatológico da peça cirúrgica, quando disponível. MATERIAIS E MÉTODOS: Foram revisados os prontuários e laudos diagnósticos de 262 pacientes com tumores de partes moles submetidos a BPAG guiada por TC em um centro de referência oncológico entre 2003 e 2009. RESULTADOS: Das 262 biópsias realizadas, foi possível a obtenção de amostra adequada em 215 (82,1%. Os tumores mais prevalentes foram os sarcomas (38,6%, carcinomas metastáticos (28,8%, tumores mesenquimais benignos (20,5% e linfomas (9,3%. Foi possível realizar graduação histológica em 92,8% dos pacientes com sarcoma, sendo a maioria (77,9% classificada como alto grau. Do total de pacientes, 116 (44,3% realizaram cirurgia para exérese e confirmação diagnóstica. A BPAG mostrou acurácia de 94,6% na identificação de sarcomas, com sensibilidade de 96,4% e especificidade de 89,5%. A graduação histológica teve concordância significativa entre a BPAG e a peça cirúrgica (p < 0,001; kappa = 0,75. CONCLUSÃO: A BPAG guiada por TC demonstrou elevada acurácia diagnóstica na avaliação de tumores de partes moles e na graduação histológica dos sarcomas, permitindo um adequado planejamento terapêutico.

  14. Partial model checking

    DEFF Research Database (Denmark)

    Andersen, Henrik Reif

    1995-01-01

    A major obstacle in applying finite-state model checking to the verification of large systems is the combinatorial explosion of the state space arising when many loosely coupled parallel processes are considered. The problem also known as the state-explosion problem has been attacked from various...... sides. This paper presents a new approach based on partial model checking where parts of the concurrent system are gradually removed while transforming the specification accordingly. When the intermediate specifications constructed in this manner can be kept small, the state-explosion problem is avoided...

  15. Partial differential equations

    CERN Document Server

    Agranovich, M S

    2002-01-01

    Mark Vishik's Partial Differential Equations seminar held at Moscow State University was one of the world's leading seminars in PDEs for over 40 years. This book celebrates Vishik's eightieth birthday. It comprises new results and survey papers written by many renowned specialists who actively participated over the years in Vishik's seminars. Contributions include original developments and methods in PDEs and related fields, such as mathematical physics, tomography, and symplectic geometry. Papers discuss linear and nonlinear equations, particularly linear elliptic problems in angles and gener

  16. Partially ordered algebraic systems

    CERN Document Server

    Fuchs, Laszlo

    2011-01-01

    Originally published in an important series of books on pure and applied mathematics, this monograph by a distinguished mathematician explores a high-level area in algebra. It constitutes the first systematic summary of research concerning partially ordered groups, semigroups, rings, and fields. The self-contained treatment features numerous problems, complete proofs, a detailed bibliography, and indexes. It presumes some knowledge of abstract algebra, providing necessary background and references where appropriate. This inexpensive edition of a hard-to-find systematic survey will fill a gap i

  17. Generalized Partial Volume

    DEFF Research Database (Denmark)

    Darkner, Sune; Sporring, Jon

    2011-01-01

    Mutual Information (MI) and normalized mutual information (NMI) are popular choices as similarity measure for multimodal image registration. Presently, one of two approaches is often used for estimating these measures: The Parzen Window (PW) and the Generalized Partial Volume (GPV). Their theoret...... of view as well as w.r.t. computational complexity. Finally, we present algorithms for both approaches for NMI which is comparable in speed to Sum of Squared Differences (SSD), and we illustrate the differences between PW and GPV on a number of registration examples....

  18. Partial differential equations

    CERN Document Server

    Levine, Harold

    1997-01-01

    The subject matter, partial differential equations (PDEs), has a long history (dating from the 18th century) and an active contemporary phase. An early phase (with a separate focus on taut string vibrations and heat flow through solid bodies) stimulated developments of great importance for mathematical analysis, such as a wider concept of functions and integration and the existence of trigonometric or Fourier series representations. The direct relevance of PDEs to all manner of mathematical, physical and technical problems continues. This book presents a reasonably broad introductory account of the subject, with due regard for analytical detail, applications and historical matters.

  19. Elliptic partial differential equations

    CERN Document Server

    Han, Qing

    2011-01-01

    Elliptic Partial Differential Equations by Qing Han and FangHua Lin is one of the best textbooks I know. It is the perfect introduction to PDE. In 150 pages or so it covers an amazing amount of wonderful and extraordinary useful material. I have used it as a textbook at both graduate and undergraduate levels which is possible since it only requires very little background material yet it covers an enormous amount of material. In my opinion it is a must read for all interested in analysis and geometry, and for all of my own PhD students it is indeed just that. I cannot say enough good things abo

  20. Partial differential equations

    CERN Document Server

    Sloan, D; Süli, E

    2001-01-01

    /homepage/sac/cam/na2000/index.html7-Volume Set now available at special set price ! Over the second half of the 20th century the subject area loosely referred to as numerical analysis of partial differential equations (PDEs) has undergone unprecedented development. At its practical end, the vigorous growth and steady diversification of the field were stimulated by the demand for accurate and reliable tools for computational modelling in physical sciences and engineering, and by the rapid development of computer hardware and architecture. At the more theoretical end, the analytical insight in

  1. Chrysler Pentastar direct hydrogen fuel cell program

    Energy Technology Data Exchange (ETDEWEB)

    Kimble, M.; Deloney, D.

    1995-08-01

    The Chrysler Pentastar Electronics, Inc. Direct Hydrogen Fueled PEM Fuel Cell Hybrid Vehicle Program (DPHV) was initiated 1 July, 1994 with the following mission, {open_quotes}Design, fabricate, and test a Direct Hydrogen Fueled Proton Exchange Membrane (PEM) Fuel Cell System including onboard hydrogen storage, an efficient lightweight fuel cell, a gas management system, peak power augmentation and a complete system controls that can be economically mass produced and comply with all safety environmental and consumer requirements for vehicle applications for the 21st century.{close_quotes} The Conceptual Design for the entire system based upon the selection of an applicable vehicle and performance requirements that are consistent with the PNGV goals will be discussed. A Hydrogen Storage system that has been selected, packaged, and partially tested in accordance with perceived Hydrogen Safety and Infrastructure requirements will be discussed in addition to our Fuel Cell approach along with design of the {open_quotes}real{close_quotes} module. The Gas Management System and the Load Leveling System have been designed and the software programs have been developed and will be discussed along with a complete fuel cell test station that has the capability to test up to a 60 kW fuel cell system.

  2. Capacity retention in hydrogen storage alloys

    Science.gov (United States)

    Anani, A.; Visintin, A.; Srinivasan, S.; Appleby, A. J.; Reilly, J. J.; Johnson, J. R.

    1992-01-01

    Results of our examination of the properties of several candidate materials for hydrogen storage electrodes and their relation to the decrease in H-storage capacity upon open-circuit storage over time are reported. In some of the alloy samples examined to date, only about 10 percent of the hydrogen capacity was lost upon storage for 20 days, while in others, this number was as high as 30 percent for the same period of time. This loss in capacity is attributed to two separate mechanisms: (1) hydrogen desorbed from the electrode due to pressure differences between the cell and the electrode sample; and (2) chemical and/or electrochemical degradation of the alloy electrode upon exposure to the cell environment. The former process is a direct consequence of the equilibrium dissociation pressure of the hydride alloy phase and the partial pressure of hydrogen in the hydride phase in equilibrium with that in the electrolyte environment, while the latter is related to the stability of the alloy phase in the cell environment. Comparison of the equilibrium gas-phase dissociation pressures of these alloys indicate that reversible loss of hydrogen capacity is higher in alloys with P(eqm) greater than 1 atm than in those with P(eqm) less than 1 atm.

  3. Pathways to Metallic Hydrogen

    OpenAIRE

    Silvera, Isaac F.; Deemyad, Shanti

    2008-01-01

    The traditional pathway that researchers have used in the goal of producing atomic metallic hydrogen is to compress samples with megabar pressures at low temperature. A number of phases have been observed in solid hydrogen and its isotopes, but all are in the insulating phase. The results of experiment and theory for this pathway are reviewed. In recent years a new pathway has become the focus of this challenge of producing metallic hydrogen, namely a path along the melting line. It has bee...

  4. Hydrogen Fuel Cell Vehicles

    OpenAIRE

    Delucchi, Mark

    1992-01-01

    Hydrogen is an especially attractive transportation fuel. It is the least polluting fuel available, and can be produced anywhere there is water and a clean source of electricity. A fuel cycle in which hydrogen is produced by solar-electrolysis of water, or by gasification of renewably grown biomass, and then used in a fuel-cell powered electric-motor vehicle (FCEV), would produce little or no local, regional, or global pollution. Hydrogen FCEVs would combine the best features of bat...

  5. Experts' Understanding of Partial Derivatives Using the Partial Derivative Machine

    Science.gov (United States)

    Roundy, David; Weber, Eric; Dray, Tevian; Bajracharya, Rabindra R.; Dorko, Allison; Smith, Emily M.; Manogue, Corinne A.

    2015-01-01

    Partial derivatives are used in a variety of different ways within physics. Thermodynamics, in particular, uses partial derivatives in ways that students often find especially confusing. We are at the beginning of a study of the teaching of partial derivatives, with a goal of better aligning the teaching of multivariable calculus with the needs of…

  6. Development of dense ceramic membranes for hydrogen separation.

    Energy Technology Data Exchange (ETDEWEB)

    Balachandran, U.; Lee, T. H.; Zhang, G.; Dorris, S. E.; Rothenberger, K. S.; Martello, D. V.; Cugini, A. V.; Siriwardane, R. V.; Poston, J. A., Jr.; Fisher, E. P.

    2000-11-01

    We developed novel cermet (i.e., ceramic-metal composite) membranes for separating hydrogen from gas mixtures at high temperature and pressure. The hydrogen permeation rate in the temperature range of 600-900 C was determined for three classes of cermet membranes (ANL-1, ANL-2, and ANL-3). Among these membranes, ANL-3 showed the highest hydrogen permeation rate, with a maximum flux of 3.2 cm{sup 3}/min-cm{sup 2} for a 0.23-mm-thick membrane at 900 C. Effects of membrane thickness and hydrogen partial pressure on permeation rate indicated that bulk diffusion of hydrogen is rate-limiting for ANL-3 membranes. The lack of degradation in permeation rate during exposure to a simulated syngas mixture suggests that ANL-3 membranes are chemically stable and suitable for long-term operation.

  7. Materials for the scavanging of hydrogen at high temperatures

    Science.gov (United States)

    Shepodd, Timothy J.; Phillip, Bradley L.

    1997-01-01

    A hydrogen getter composition comprising a double or triple bonded hydrocarbon with a high melting point useful for removing hydrogen gas, to partial pressures below 0.01 torr, from enclosed spaces and particularly from vessels used for transporting or containing fluids at elevated temperatures. The hydrogen getter compostions disclosed herein and their reaction products will neither melt nor char at temperatures in excess of 100C. They possess significant advantages over conventional hydrogen getters, namely low risk of fire or explosion, no requirement for high temperature activation or operation, the ability to absorb hydrogen even in the presence of contaminants such as water, water vapor, common atmospheric gases and oil mists and are designed to be disposed within the confines of the apparatus. These getter materials can be mixed with binders, such as fluropolymers, which permit the getter material to be fabricated into useful shapes and/or impart desirable properties such as water repellency or impermeability to various gases.

  8. Liquid hydrogen in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Yasumi, S. [Iwatani Corp., Osaka (Japan). Dept. of Overseas Business Development

    2009-07-01

    Japan's Iwatani Corporation has focused its attention on hydrogen as the ultimate energy source in future. Unlike the United States, hydrogen use and delivery in liquid form is extremely limited in the European Union and in Japan. Iwatani Corporation broke through industry stereotypes by creating and building Hydro Edge Co. Ltd., Japan's largest liquid hydrogen plant. It was established in 2006 as a joint venture between Iwatani and Kansai Electric Power Group in Osaka. Hydro Edge is Japan's first combined liquid hydrogen and ASU plant, and is fully operational. Liquid oxygen, liquid nitrogen and liquid argon are separated from air using the cryogenic energy of liquefied natural gas fuel that is used for power generation. Liquid hydrogen is produced efficiently and simultaneously using liquid nitrogen. Approximately 12 times as much hydrogen in liquid form can be transported and supplied as pressurized hydrogen gas. This technology is a significant step forward in the dissemination and expansion of hydrogen in a hydrogen-based economy.

  9. Achados histológicos em 48 pacientes transplantados do fígado: biópsias do enxerto pós-reperfusão (tempo zero e de três a 15 dias pós-transplante

    Directory of Open Access Journals (Sweden)

    Castro Alexandre Fonseca de

    2002-01-01

    Full Text Available Introdução: As relações entre a morfologia do enxerto transplantado e a do período pós-transplante são importantes no acompanhamento dos pacientes e no direcionamento dos tratamentos instituídos. Objetivo: Analisar os achados histológicos do enxerto hepático em biópsiasrealizadas pós-reperfusão (tempo zero e naquelas realizadas de três a 15 dias pós-transplante. Materiais e métodos: Noventa e seis biópsias de 48 pacientes foram selecionadas por terem sido colhidas no tempo zero (pós-reperfusão e no período compreendido entre o terceiro e o 15º dia pós-transplante, com identificação das lesões hepatocitárias degenerativas, necrose e atividadeinflamatória. As biópsias pós-transplante foram ainda graduadas quanto ao índice de atividade de rejeição (IAR, segundo o consenso de Banff. Resultados: Osachados histopatológicos mais freqüentes nas biópsias pós-reperfusão foram de degeneração hidrópica discreta (acometimento de até 50% dos hepatócitos em 87,5% dos casos e necrose focal intralobular (lítica, apoptose presente em 75% dos pacientes, em graus variáveis. Nas biópsiasrealizadas pós-transplante encontrou-se degeneração hidrópica discreta também em 87,5% dos casos e rejeição aguda em 38 (79,2% pacientes. Nestas biópsias com rejeição aguda, chamou atenção a intensidade da agressão a ductos biliares em graus moderado (2 e acentuado (3 presentes em 42,1% dos casos, enquanto a endotelialite portal, nestas mesmas intensidades, ocorreu em 21,05%. Conclusão: Nossos dados evidenciaram lesões relacionadas à preservação (lesões do tipo harvesting nas biópsias pós-reperfusão. As biópsias pós-transplante revelaram índice de rejeição morfológica na maioria dos casos, como evidenciado na literatura, destacando-se aqui a intensidade da agressão a ductos biliares.

  10. Furnace brazing under partial vacuum

    Science.gov (United States)

    Mckown, R. D.

    1979-01-01

    Brazing furnace utilizing partial-vacuum technique reduces tooling requirements and produces better bond. Benefit in that partial vacuum helps to dissociate metal oxides that inhibit metal flow and eliminates heavy tooling required to hold parts together during brazing.

  11. Tutorial on Online Partial Evaluation

    Directory of Open Access Journals (Sweden)

    William R. Cook

    2011-09-01

    Full Text Available This paper is a short tutorial introduction to online partial evaluation. We show how to write a simple online partial evaluator for a simple, pure, first-order, functional programming language. In particular, we show that the partial evaluator can be derived as a variation on a compositionally defined interpreter. We demonstrate the use of the resulting partial evaluator for program optimization in the context of model-driven development.

  12. Enhancing hydrogen spillover and storage

    Science.gov (United States)

    Yang, Ralph T [Ann Arbor, MI; Li, Yingwel [Ann Arbor, MI; Lachawiec, Jr., Anthony J.

    2011-05-31

    Methods for enhancing hydrogen spillover and storage are disclosed. One embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the hydrogen receptor to ultrasonification as doping occurs. Another embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the doped hydrogen receptor to a plasma treatment.

  13. Enhancing hydrogen spillover and storage

    Science.gov (United States)

    Yang, Ralph T; Li, Yingwei; Lachawiec, Jr., Anthony J

    2013-02-12

    Methods for enhancing hydrogen spillover and storage are disclosed. One embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the hydrogen receptor to ultrasonication as doping occurs. Another embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the doped hydrogen receptor to a plasma treatment.

  14. Type-Directed Partial Evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier

    1998-01-01

    Type-directed partial evaluation uses a normalization function to achieve partial evaluation. These lecture notes review its background, foundations, practice, and applications. Of specific interest is the modular technique of offline and online type-directed partial evaluation in Standard ML of ...

  15. Type-Directed Partial Evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier

    1998-01-01

    Type-directed partial evaluation uses a normalization function to achieve partial evaluation. These lecture notes review its background, foundations, practice, and applications. Of specific interest is the modular technique of offline and online type-directed partial evaluation in Standard ML...

  16. Incidência da cardiopatia chagásica em 15.000 necrópsias consecutivas e sua associação com os «megas»

    Directory of Open Access Journals (Sweden)

    A. J. A. Barbosa

    1970-08-01

    Full Text Available Os AA. estudaram, a incidência da cardiopatia chagásica em 15.000 necrópsias consecutivas e sua associação com os megas. Em 875 cardiopatias chagásicas houve 145 casos de megas, ou seja, 16,56%, com predominância do sexo masculino. No branco houve maior incidência (55 de megas do que no mulato (53 e no negro (31 dentre 858 cardiopatias chagásicas. Em 848 cardiopatias chagásicas, 85,78% eram de indivíduos que faleceram entre 21 e 60 anos. O maior número de cardiopatias (120 ou 14,14% e de "megas'' (21 ou 15,78% foi encontrado nos indivíduos entre 36 a 40 anos. Os nossos resultados mostram uma incidência diferente da associação cardiopatia-mega, em comparação da observada em outras regiões do País e em outros países da América do Sul.

  17. Biópsia de pele e seu estudo histológico: Por quê? Para quê? Como? Parte I Skin biopsy and its histopathologic analysis: Why? What for? How? Part I

    Directory of Open Access Journals (Sweden)

    Betina Werner

    2009-08-01

    Full Text Available O estudo anatomopatológico é, na maioria das vezes, considerado padrão-ouro para esclarecimento diagnóstico de lesões neoplásicas ou inflamatórias de pele. Para que o resultado histopatológico da biópsia de pele seja satisfatório, no entanto, o médico deve estar ciente das razões para fazê-la em seguida de exame microscópico, dos objetivos a serem atingidos e da melhor maneira de se realizá-la, incluindo a escolha da melhor técnica e do melhor local anatômico para se retirar o fragmento de pele, dependendo da doença.Histopathologic study is considered gold-standard for diagnosis of skin lesions, either neoplastic or inflammatory, most of the times. To take the most out of a skin biopsy, physicians should be aware of the reasons for performing the procedure followed by microscopic examination, the objectives to be achieved and the best manner to do the biopsy, including the best technique and best anatomical site for a particular disease.

  18. Validade da citologia e da biópsia orientada pela colposcopia no diagnóstico do carcinoma cervical pré-clínico Validity of cytology and colposcopy - guided biopsy for the diagnosis of preclinical cervical carcinoma

    Directory of Open Access Journals (Sweden)

    Aldo Franklin Ferreira Reis

    1999-05-01

    Full Text Available Objetivo: avaliar a eficácia da citologia e da biópsia orientada pela colposcopia na discriminação entre o carcinoma invasor pré-clínico e as lesões intra-epiteliais. Pacientes e Métodos: 441 pacientes submetidas a conização, histerectomia e operação de Wertheim-Meigs, no período de 1978 a 1995, no Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Setor de Patologia Cervical. Foram efetuados os cálculos da sensibilidade, especificidade, valores preditivos, razão de verossimilhança e intervalos de confiança de cada exame, divididos em quatro categorias: normal e inflamatório; displasia leve e displasia moderada; displasia acentuada e carcinoma in situ, e carcinoma microinvasor e invasor. As biópsias foram analisadas como um todo e separadas pelo tipo de colposcopia (satisfatória e insatisfatória. Resultados: a citologia mostrou sensibilidade de 50%, especificidade de 89%, valor preditivo positivo de 63% e valor preditivo negativo de 82%. As razões de verossimilhança foram 4,4 para o diagnóstico de invasão, 0,7 para displasia acentuada e carcinoma in situ, 0,1 para displasia leve e moderada, 2,2 para normal e inflamatório e 0,6 para o conjunto de resultados negativos para invasão. A biópsia orientada pela colposcopia apresentou sensibilidade de 50%, especificidade de 100%, valor preditivo positivo de 100% e valor preditivo negativo de 83%. As razões de verossimilhança foram: tendendo ao ¥ para o resultado de invasão, 0,5 para displasia acentuada e carcinoma in situ, 0,2 para displasia leve e moderada, 0,3 para normal e inflamatório e 0,5 para o conjunto de resultados negativos para invasão. A biópsia orientada pela colposcopia satisfatória com lesão visível mostrou sensibilidade de 59%, especificidade de 100%, valor preditivo positivo de 100% e valor preditivo negativo de 83%. As razões de verossimilhança foram: tendendo ao ¥ para o resultado positivo de invasão, 0

  19. Coleta e preservação do líquido pleural e biópsia pleural Collection and preservation of the pleural fluid and pleural biopsy

    Directory of Open Access Journals (Sweden)

    Leila Antonangelo

    2006-08-01

    Full Text Available As amostras de líquido pleural obtidas por toracocentese para o diagnóstico de transudatos e exsudatos devem obedecer a uma rotina de coleta e preservação para a realização de uma análise laboratorial adequada. Igualmente, fragmentos de biópsia de pleura obtidos para o diagnóstico diferencial dos exsudatos devem ser coletados de forma sistemática com o objetivo de otimizar o diagnóstico e facilitar a instituição da terapêutica adequada.The samples of pleural fluid obtained by thoracentesis for the diagnosis of transudates and exudates shall follow a routine of collection and preservation for an appropriate laboratorial analysis. Equally, fragments of pleura biopsy obtained for the differential diagnosis of the exudates should be collected in a systematic way in order to optimize the diagnosis and facilitate the institution of appropriate therapeutics actions.

  20. Enthalpy measurement of coal-derived liquids. Quarterly technical progress report, October-December 1980. [2,6-dimethylpyridine; 105 to 705/sup 0/F; 50 to 1500 psia

    Energy Technology Data Exchange (ETDEWEB)

    Kidnay, A.J.; Yesavage, V.F.

    1981-02-15

    Equipment modifications to the Freon flow system of a reference fluid boil-off calorimeter are described. These modifications, along with a new equipment start-up procedure, have resulted in enhanced system stability, and consequently, better accuracy in the measurements. A thorough check of equipment calibration and operation was conducted to assure the validity of the experimental data. Using the flow calorimeter, enthalpy measurements were made for 2,6-dimethylpyridine. The data were taken over a temperature range of 105 to 745/sup 0/F along 50, 100, 200, 400, 576, 750, 1000, and 1500 psia isobars. Thermodynamic properties derived from the data were successfully compared to corresponding literature values. The measured quantities were also compared to those calculated from correlations using the SRK equation of state and a modification of the BWR equation of state by Kesler and Lee, and there is good agreement. However, comparisons between measured and calculated quantities are limited by the lack of ideal gas heat capacity data.

  1. Fundamental partial compositeness

    CERN Document Server

    Sannino, Francesco

    2016-01-01

    We construct renormalizable Standard Model extensions, valid up to the Planck scale, that give a composite Higgs from a new fundamental strong force acting on fermions and scalars. Yukawa interactions of these particles with Standard Model fermions realize the partial compositeness scenario. Successful models exist because gauge quantum numbers of Standard Model fermions admit a minimal enough 'square root'. Furthermore, right-handed SM fermions have an SU(2)$_R$-like structure, yielding a custodially-protected composite Higgs. Baryon and lepton numbers arise accidentally. Standard Model fermions acquire mass at tree level, while the Higgs potential and flavor violations are generated by quantum corrections. We further discuss accidental symmetries and other dynamical features stemming from the new strongly interacting scalars. If the same phenomenology can be obtained from models without our elementary scalars, they would reappear as composite states.

  2. Applied partial differential equations

    CERN Document Server

    Logan, J David

    2004-01-01

    This primer on elementary partial differential equations presents the standard material usually covered in a one-semester, undergraduate course on boundary value problems and PDEs. What makes this book unique is that it is a brief treatment, yet it covers all the major ideas: the wave equation, the diffusion equation, the Laplace equation, and the advection equation on bounded and unbounded domains. Methods include eigenfunction expansions, integral transforms, and characteristics. Mathematical ideas are motivated from physical problems, and the exposition is presented in a concise style accessible to science and engineering students; emphasis is on motivation, concepts, methods, and interpretation, rather than formal theory. This second edition contains new and additional exercises, and it includes a new chapter on the applications of PDEs to biology: age structured models, pattern formation; epidemic wave fronts, and advection-diffusion processes. The student who reads through this book and solves many of t...

  3. Fundamental partial compositeness

    Energy Technology Data Exchange (ETDEWEB)

    Sannino, Francesco [CP-Origins and Danish IAS, University of Southern Denmark,Campusvej 55 (Denmark); Strumia, Alessandro [Dipartimento di Fisica dell’Università di Pisa and INFN,Pisa (Italy); Theory Division, CERN,Geneva (Switzerland); Tesi, Andrea [Department of Physics, Enrico Fermi Institute, University of Chicago,Chicago, IL 60637 (United States); Vigiani, Elena [Dipartimento di Fisica dell’Università di Pisa and INFN,Pisa (Italy)

    2016-11-07

    We construct renormalizable Standard Model extensions, valid up to the Planck scale, that give a composite Higgs from a new fundamental strong force acting on fermions and scalars. Yukawa interactions of these particles with Standard Model fermions realize the partial compositeness scenario. Under certain assumptions on the dynamics of the scalars, successful models exist because gauge quantum numbers of Standard Model fermions admit a minimal enough ‘square root’. Furthermore, right-handed SM fermions have an SU(2){sub R}-like structure, yielding a custodially-protected composite Higgs. Baryon and lepton numbers arise accidentally. Standard Model fermions acquire mass at tree level, while the Higgs potential and flavor violations are generated by quantum corrections. We further discuss accidental symmetries and other dynamical features stemming from the new strongly interacting scalars. If the same phenomenology can be obtained from models without our elementary scalars, they would reappear as composite states.

  4. Elliptic partial differential equations

    CERN Document Server

    Volpert, Vitaly

    If we had to formulate in one sentence what this book is about it might be "How partial differential equations can help to understand heat explosion, tumor growth or evolution of biological species". These and many other applications are described by reaction-diffusion equations. The theory of reaction-diffusion equations appeared in the first half of the last century. In the present time, it is widely used in population dynamics, chemical physics, biomedical modelling. The purpose of this book is to present the mathematical theory of reaction-diffusion equations in the context of their numerous applications. We will go from the general mathematical theory to specific equations and then to their applications. Mathematical anaylsis of reaction-diffusion equations will be based on the theory of Fredholm operators presented in the first volume. Existence, stability and bifurcations of solutions will be studied for bounded domains and in the case of travelling waves. The classical theory of reaction-diffusion equ...

  5. Partial pressure gauges

    CERN Document Server

    Peter, G J

    2007-01-01

    The determination of partial pressures in vacuum systems is usually performed by mass spectrometers. The most common type is the QMS. Quadrupole mass spectrometers were developed decades ago and have been used by vacuum specialists as a diagnostic tool since then. In the first part of the paper the principles of these mass spectrometers are briefly reviewed together with the key features of the instruments. This is necessary to operate these instruments. In the second part the boundary conditions which arise from the application as residual gas analyser in UHV/XHV plants are described. These lead to special versions of mass spectrometers. Results obtained with these instruments and typical artefacts in mass spectra obtained in the UHV are discussed.

  6. Hydrogen Storage Tank

    CERN Multimedia

    1983-01-01

    This huge stainless steel reservoir,placed near an end of the East Hall, was part of the safety equipment connected to the 2 Metre liquid hydrogen Bubble Chamber. It could store all the hydrogen in case of an emergency. The picture shows the start of its demolition.

  7. Metastable ultracondensed hydrogenous materials

    Science.gov (United States)

    Nellis, W. J.

    2017-12-01

    The primary purpose of this paper is to stimulate theoretical predictions of how to retain metastably hydrogenous materials made at high pressure P on release to ambient. Ultracondensed metallic hydrogen has been made at high pressures in the fluid and reported made probably in the solid. Because the long quest for metallic hydrogen is likely to be concluded in the relatively near future, a logical question is whether another research direction, comparable in scale to the quest for metallic H, will arise in high pressure research. One possibility is retention of metastable solid metallic hydrogen and other hydrogenous materials on release of dynamic and static high pressures P to ambient. If hydrogenous materials could be retained metastably on release, those materials would be a new class of materials for scientific investigations and technological applications. This paper is a review of the current situation with the synthesis of metallic hydrogen, potential technological applications of metastable metallic H and other hydrogenous materials at ambient, and general background of published experimental and theoretical work on what has been accomplished with metastable phases in the past and thus what might be accomplished in the future.

  8. Hydrogen evolution reaction catalyst

    Science.gov (United States)

    Subbaraman, Ram; Stamenkovic, Vojislav; Markovic, Nenad; Tripkovic, Dusan

    2016-02-09

    Systems and methods for a hydrogen evolution reaction catalyst are provided. Electrode material includes a plurality of clusters. The electrode exhibits bifunctionality with respect to the hydrogen evolution reaction. The electrode with clusters exhibits improved performance with respect to the intrinsic material of the electrode absent the clusters.

  9. Dark hydrogen fermentations

    NARCIS (Netherlands)

    Vrije, de G.J.; Claassen, P.A.M.

    2003-01-01

    The production of hydrogen is a ubiquitous, natural phenomenon under anoxic or anaerobic conditions. A wide variety of bacteria, in swamps, sewage, hot springs, the rumen of cattle etc. is able to convert organic matter to hydrogen, CO2 and metabolites like acetic acid, lactate, ethanol and alanine.

  10. Electrochemical Hydrogen Compressor

    Energy Technology Data Exchange (ETDEWEB)

    Lipp, Ludwig [FuelCell Energy, Inc., Torrington, CT (United States)

    2016-01-21

    Conventional compressors have not been able to meet DOE targets for hydrogen refueling stations. They suffer from high capital cost, poor reliability and pose a risk of fuel contamination from lubricant oils. This project has significantly advanced the development of solid state hydrogen compressor technology for multiple applications. The project has achieved all of its major objectives. It has demonstrated capability of Electrochemical Hydrogen Compression (EHC) technology to potentially meet the DOE targets for small compressors for refueling sites. It has quantified EHC cell performance and durability, including single stage hydrogen compression from near-atmospheric pressure to 12,800 psi and operation of EHC for more than 22,000 hours. Capital cost of EHC was reduced by 60%, enabling a path to meeting the DOE cost targets for hydrogen compression, storage and delivery ($2.00-2.15/gge by 2020).

  11. Chlorific efficiency of coal hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Schappert, H.

    1942-10-20

    In studies on the calorific efficiency of coal hydrogenation, the efficiency for H/sub 2/ production was calculated to be 26%, the efficiency for hydrogenation was calculated to be 49%, and the efficiency of hydrogenation including H/sub 2/ production was 27.2%. The efficiency of hydrogenation plus hydrogen production was almost equal to the efficiency of hydrogen production alone, even though this was not expected because of the total energy calculated in the efficiency of hydrogenation proper. It was entirely possible, but did not affect computations, that the efficiency of one or the other components of hydrogenation process differed somewhat from 49%. The average efficiency for all cases was 49%. However, when hydrogen was not bought, but was produced--(efficiency of hydrogen production was 26%, not 100%-- then the total energy changed and the efficiency of hydrogen production and combination was not 26%, but 13%. This lower value explained the drop of hydrogenation efficiency to 27.2%.

  12. Robot-assisted partial nephrectomy: Superiority over laparoscopic partial nephrectomy.

    Science.gov (United States)

    Shiroki, Ryoichi; Fukami, Naohiko; Fukaya, Kosuke; Kusaka, Mamoru; Natsume, Takahiro; Ichihara, Takashi; Toyama, Hiroshi

    2016-02-01

    Nephron-sparing surgery has been proven to positively impact the postoperative quality of life for the treatment of small renal tumors, possibly leading to functional improvements. Laparoscopic partial nephrectomy is still one of the most demanding procedures in urological surgery. Laparoscopic partial nephrectomy sometimes results in extended warm ischemic time and severe complications, such as open conversion, postoperative hemorrhage and urine leakage. Robot-assisted partial nephrectomy exploits the advantages offered by the da Vinci Surgical System to laparoscopic partial nephrectomy, equipped with 3-D vision and a better degree in the freedom of surgical instruments. The introduction of the da Vinci Surgical System made nephron-sparing surgery, specifically robot-assisted partial nephrectomy, safe with promising results, leading to the shortening of warm ischemic time and a reduction in perioperative complications. Even for complex and challenging tumors, robotic assistance is expected to provide the benefit of minimally-invasive surgery with safe and satisfactory renal function. Warm ischemic time is the modifiable factor during robot-assisted partial nephrectomy to affect postoperative kidney function. We analyzed the predictive factors for extended warm ischemic time from our robot-assisted partial nephrectomy series. The surface area of the tumor attached to the kidney parenchyma was shown to significantly affect the extended warm ischemic time during robot-assisted partial nephrectomy. In cases with tumor-attached surface area more than 15 cm(2) , we should consider switching robot-assisted partial nephrectomy to open partial nephrectomy under cold ischemia if it is imperative. In Japan, a nationwide prospective study has been carried out to show the superiority of robot-assisted partial nephrectomy to laparoscopic partial nephrectomy in improving warm ischemic time and complications. By facilitating robotic technology, robot-assisted partial nephrectomy

  13. Effect of storage and LEO cycling on manufacturing technology IPV nickel-hydrogen cells

    Science.gov (United States)

    Smithrick, John J.

    1987-01-01

    Yardney Manufacturing Technology (MANTECH) 50 A-hr space weight individual pressure vessel nickel-hydrogen cells were evaluated. This consisted of investigating: the effect of storage and charge/discharge cycling on cell performance. For the storage test the cells were precharged with hydrogen, by the manufacturer, to a pressure of 14.5 psia. After undergoing activation and acceptance tests, the cells were discharged at C/10 rate (5A) to 0.1 V or less. The terminals were then shorted. The cells were shipped to NASA Lewis Research Center where they were stored at room temperature in the shorted condition for 1 year. After storage, the acceptance tests were repeated at NASA Lewis. A comparison of test results indicate no significant degradation in electrical performance due to 1 year storage. For the cycle life test the regime was a 90 minute low earth orbit at deep depths of discharge (80 and 60 percent). At the 80 percent DOD the three cells failed on the average at cycle 741. Failure for this test was defined to occur when the cell voltage degraded to 1 V prior to completion of the 35 min discharge. The DOD was reduced to 60 percent. The cycle life test was continued.

  14. Partially supervised speaker clustering.

    Science.gov (United States)

    Tang, Hao; Chu, Stephen Mingyu; Hasegawa-Johnson, Mark; Huang, Thomas S

    2012-05-01

    Content-based multimedia indexing, retrieval, and processing as well as multimedia databases demand the structuring of the media content (image, audio, video, text, etc.), one significant goal being to associate the identity of the content to the individual segments of the signals. In this paper, we specifically address the problem of speaker clustering, the task of assigning every speech utterance in an audio stream to its speaker. We offer a complete treatment to the idea of partially supervised speaker clustering, which refers to the use of our prior knowledge of speakers in general to assist the unsupervised speaker clustering process. By means of an independent training data set, we encode the prior knowledge at the various stages of the speaker clustering pipeline via 1) learning a speaker-discriminative acoustic feature transformation, 2) learning a universal speaker prior model, and 3) learning a discriminative speaker subspace, or equivalently, a speaker-discriminative distance metric. We study the directional scattering property of the Gaussian mixture model (GMM) mean supervector representation of utterances in the high-dimensional space, and advocate exploiting this property by using the cosine distance metric instead of the euclidean distance metric for speaker clustering in the GMM mean supervector space. We propose to perform discriminant analysis based on the cosine distance metric, which leads to a novel distance metric learning algorithm—linear spherical discriminant analysis (LSDA). We show that the proposed LSDA formulation can be systematically solved within the elegant graph embedding general dimensionality reduction framework. Our speaker clustering experiments on the GALE database clearly indicate that 1) our speaker clustering methods based on the GMM mean supervector representation and vector-based distance metrics outperform traditional speaker clustering methods based on the “bag of acoustic features” representation and statistical

  15. Positron impact ionization of atomic hydrogen at low energies

    Indian Academy of Sciences (India)

    energies. K CHAKRABARTI. Department of Mathematics, Scottish Church College, 1 & 3 Urquhart Square, Calcutta 700 006,. India. MS received 26 June 2000. Abstract. Low energy positron impact ionization of atomic hydrogen is studies theoretically using the hyperspherical partial wave method of Das [1] in constant ΘЅѕ, ...

  16. Positron impact ionization of atomic hydrogen at low energies

    Indian Academy of Sciences (India)

    Low energy positron impact ionization of atomic hydrogen is studies theoretically using the hyperspherical partial wave method of Das [1] in constant 12, equal energy sharing geometry. The TDCS reveal considerable differences in physics compared to electron impact ionization under the same geometry.

  17. The hydrogen highway

    Energy Technology Data Exchange (ETDEWEB)

    Grigg, A. [Fuel Cells Canada, Vancouver, British Columbia (Canada)

    2004-07-01

    'Full text:' The Hydrogen Highway in British Columbia, Canada, is a coordinated, large-scale demonstration and deployment program aimed at accelerating the commercialization of hydrogen and fuel cell technologies and products. It will be a showcase for fuel cell vehicles, refuelling stations and stationary power systems leading up to the 2010 Olympic and Paralympic Winter Games in Whistler, BC. The Hydrogen Highway is designed to help address many of the challenges to commercialization identified in the Canadian Fuel Cell Commercialization Roadmap. The project will create an early adopter network of hydrogen and fuel cell microenvironments where technology developers and users can learn about the technical, economic, environmental and social impacts of products. The Hydrogen Highway will give the public and potential purchasers an opportunity to feel, touch and see the new technology, as well as provide the industry with a venue in which to develop industry standards and supply chains of materials and components. While demonstration and deployment programs are a recognized and necessary component in the process to commercialize hydrogen and fuel cell technologies, there is no handbook describing how it should be done. This paper will describe the history, objectives, project details and some of the challenges associated with establishing Canada's Hydrogen Highway. (author)

  18. Photoelectrochemical hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Rocheleau, R.; Misra, A.; Miller, E. [Univ. of Hawaii, Honolulu, HI (United States)

    1998-08-01

    A significant component of the US DOE Hydrogen Program is the development of a practical technology for the direct production of hydrogen using a renewable source of energy. High efficiency photoelectrochemical systems to produce hydrogen directly from water using sunlight as the energy source represent one of the technologies identified by DOE to meet this mission. Reactor modeling and experiments conducted at UH provide strong evidence that direct solar-to-hydrogen conversion efficiency greater than 10% can be expected using photoelectrodes fabricated from low-cost, multijunction (MJ) amorphous silicon solar cells. Solar-to-hydrogen conversion efficiencies as high as 7.8% have been achieved using a 10.3% efficient MJ amorphous silicon solar cell. Higher efficiency can be expected with the use of higher efficiency solar cells, further improvement of the thin film oxidation and reduction catalysts, and optimization of the solar cell for hydrogen production rather than electricity production. Hydrogen and oxygen catalysts developed under this project are very stable, exhibiting no measurable degradation in KOH after over 13,000 hours of operation. Additional research is needed to fully optimize the transparent, conducting coatings which will be needed for large area integrated arrays. To date, the best protection has been afforded by wide bandgap amorphous silicon carbide films.

  19. [Post traumatic partial seizures].

    Science.gov (United States)

    Carvajal, P; Almárcegui, C; Pablo, M J; Peralta, P; Bernal, M; Valdizán, J R

    Post traumatic epilepsy represents 4% of the prevalence of the disorder and is one of the sequelas which is most difficult to prevent. Risk factors have been described to predict the appearance of seizures. A seven year old boy with a severe head injury was admitted to the Intensive Care Unit. On neuroimaging studies there were multiple foci of contusion, mainly in the left hemisphere, and blood in the III and IV ventricles and frontal horn of the left lateral ventricle. The patient had severe sequelae of head injury with a right spastic hemiplegia and hemiparesia with hypertony of the left side, together with complete blindness of both eyes due to bilateral atrophy of the optic nerve. Serial EEG were done, in which a recording showed alternating periods of hypervoltage grapho elements superimposed on a trace of very low voltage, with continuous activity of low voltage and low frequency. There were no grapho elements with acute morphology. However, the patient had a first partial seizure a year and a half after his head injury. On the EEG an epileptogenic focus was identified in the left hemisphere. Within two years of his head injury he had seven seizures. He had not received prophylactic antiepileptic treatment after the head injury. We report a case of epilepsy secondary to a head injury, in which the first seizure occurred one and a half years after injury. In view of the risk factors, we discuss whether prophylactic anti epileptic treatment might have been beneficial.

  20. A green hydrogen economy

    Energy Technology Data Exchange (ETDEWEB)

    Clark, W.W. II [Clark Communications, Beverly Hills, CA (United States). Green Hydrogen Scientific Advisory Committee; Rifkin, J. [The Foundation on Economic Trends (United States)

    2006-11-15

    This paper is the result of over a dozen scholars and practitioners who strongly felt that a hydrogen economy and hence the future is closer than some American politicians and bureaucrats state. Moreover, when seen internationally, there is strong evidence, the most recent and obvious ones are the proliferation of hybrid vehicles, that for any nation-state to be energy independent it must seek a renewable or green hydrogen future in the near term. The State of California has once again taken the lead in this effort for both an energy-independent future and one linked strongly to the hydrogen economy. Then why a hydrogen economy in the first instance? The fact is that hydrogen most likely will not be used for refueling of vehicles in the near term. The number of vehicles to make hydrogen commercially viable will not be in the mass market by almost all estimates until 2010. However, it is less than a decade away. The time frame is NOT 30-40 years as some argue. The hydrogen economy needs trained people, new ventures and public-private partnerships now. The paper points out how the concerns of today, including higher costs and technologies under development, can be turned into opportunities for both the public and private sectors. It was not too long ago that the size of a mobile phone was that of a briefcase, and then almost 10 years ago, the size of a shoe box. Today, they are not only the size of a man's wallet but also often given away free to consumers who subscribe or contract for wireless services. While hydrogen may not follow this technological commercialization exactly, it certainly will be on a parallel path. International events and local or regional security dictate that the time for a hydrogen must be close at hand. (author)

  1. Photobiological hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Seibert, M; Lien, S; Weaver, P F

    1979-01-01

    Hydrogen production by phototrophic organisms, which has been known since the 1930's, occurs at the expense of light energy and electron-donating substrates. Three classes of organisms, namely, photosynthetic bacteria, cyanobacteria, and algae carry out this function. The primary hydrogen-producing enzyme systems, hydrogenase and nitrogenase, will be discussed along with the manner in which they couple to light-driven electron transport. In addition, the feasibility of using in vivo and in vitro photobiological hydrogen producing systems in future solar energy conversion applications will be examined.

  2. Photobiological hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Seibert, M.; Lien, S.; Weaver, P.F.

    1979-01-01

    Hydrogen production by phototrophic organisms, which has been known since the 1930's, occurs at the expense of light energy and electron-donating substrates. Three classes of organisms, namely, photosynthetic bacteria, cyanobacteria, and algae carry out this function. The primary hydrogen-producing enzyme systems, hydrogenase and nitrogenase, will be discussed along with the manner in which they couple to light-driven electron transport. In addition, the feasibility of using in vivo and in vitro photobiological hydrogen producing systems in future solar energy conversion applications will be examined.

  3. Biological hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Benemann, J.R. [Univ. of California, Berkeley, CA (United States)

    1995-11-01

    Biological hydrogen production can be accomplished by either thermochemical (gasification) conversion of woody biomass and agricultural residues or by microbiological processes that yield hydrogen gas from organic wastes or water. Biomass gasification is a well established technology; however, the synthesis gas produced, a mixture of CO and H{sub 2}, requires a shift reaction to convert the CO to H{sub 2}. Microbiological processes can carry out this reaction more efficiently than conventional catalysts, and may be more appropriate for the relatively small-scale of biomass gasification processes. Development of a microbial shift reaction may be a near-term practical application of microbial hydrogen production.

  4. Chromatographic hydrogen isotope separation

    Science.gov (United States)

    Aldridge, Frederick T.

    1981-01-01

    Intermetallic compounds with the CaCu.sub.5 type of crystal structure, particularly LaNiCo.sub.4 and CaNi.sub.5, exhibit high separation factors and fast equilibrium times and therefore are useful for packing a chromatographic hydrogen isotope separation colum. The addition of an inert metal to dilute the hydride improves performance of the column. A large scale mutli-stage chromatographic separation process run as a secondary process off a hydrogen feedstream from an industrial plant which uses large volumes of hydrogen can produce large quantities of heavy water at an effective cost for use in heavy water reactors.

  5. Color Changing Hydrogen Sensors

    Science.gov (United States)

    Roberson, Luke B.; Williams, Martha; Captain, Janine E.; Mohajeri, Nahid; Raissi, Ali

    2015-01-01

    During the Space Shuttle Program, one of the most hazardous operation that occurred was the loading of liquid hydrogen (LH2) during fueling operations of the spacecraft. Due to hydrogen's low explosive limit, any amount leaked could lead to catastrophic event. Hydrogen's chemical properties make it ideal as a rocket fuel; however, the fuel is deemed unsafe for most commercial use because of the inability to easily detect the gas leaking. The increased use of hydrogen over traditional fossil fuels would reduce greenhouse gases and America's dependency on foreign oil. Therefore a technology that would improve safety at NASA and in the commercial sector while creating a new economic sector would have a huge impact to NASA's mission. The Chemochromic Detector for sensing hydrogen gas leakage is a color-changing detector that is useful in any application where it is important to know not only the presence but also the location of the hydrogen gas leak. This technology utilizes a chemochromicpigment and polymer matrix that can be molded or spun into rigid or pliable shapes useable in variable temperature environments including atmospheres of inert gas, hydrogen gas, or mixtures of gases. A change in color of the detector material indicates where gaseous hydrogen leaks are occurring. The irreversible sensor has a dramatic color change from beige to dark grey and remains dark grey after exposure. A reversible pigment changes from white to blue in the presence of hydrogen and reverts back to white in the presence of oxygen. Both versions of the sensor's pigments were comprised of a mixture of a metal oxide substrate and a hydro-chromic compound (i.e., the compound that changed color in the presence of hydrogen) and immediately notified the operator of the presence of low levels of hydrogen. The detector can be used in a variety of formats including paint, tape, caulking, injection molded parts, textiles and fabrics, composites, and films. This technology brings numerous

  6. National hydrogen energy roadmap

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2002-11-01

    This report was unveiled by Energy Secretary Spencer Abraham in November 2002 and provides a blueprint for the coordinated, long-term, public and private efforts required for hydrogen energy development. Based on the results of the government-industry National Hydrogen Energy Roadmap Workshop, held in Washington, DC on April 2-3, 2002, it displays the development of a roadmap for America's clean energy future and outlines the key barriers and needs to achieve the hydrogen vision goals defined in

  7. Searching for magnetism in hydrogenated graphene: using highly hydrogenated graphene prepared via Birch reduction of graphite oxides.

    Science.gov (United States)

    Eng, Alex Yong Sheng; Poh, Hwee Ling; Šaněk, Filip; Maryško, Miroslav; Matějková, Stanislava; Sofer, Zdeněk; Pumera, Martin

    2013-07-23

    Fully hydrogenated graphene (graphane) and partially hydrogenated graphene materials are expected to possess various fundamentally different properties from graphene. We have prepared highly hydrogenated graphene containing 5% wt of hydrogen via Birch reduction of graphite oxide using elemental sodium in liquid NH3 as electron donor and methanol as proton donor in the reduction. We also investigate the influence of preparation method of graphite oxide, such as the Staudenmaier, Hofmann or Hummers methods on the hydrogenation rate. A control experiment involving NaNH2 instead of elemental Na was also performed. The materials were characterized in detail by electron microscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy both at room and low temperatures, X-ray fluorescence spectroscopy, inductively coupled plasma optical emission spectroscopy, combustible elemental analysis and electrical resistivity measurements. Magnetic measurements are provided of bulk quantities of highly hydrogenated graphene. In the whole temperature range up to room temperature, the hydrogenated graphene exhibits a weak ferromagnetism in addition to a contribution proportional to field that is caused not only by diamagnetism but also likely by an antiferromagnetic influence. The origin of the magnetism is also determined to arise from the hydrogenated graphene itself, and not as a result of any metallic impurities.

  8. Biomimetic hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Krassen, Henning

    2009-05-15

    Hydrogenases catalyze the reduction of protons to molecular hydrogen with outstanding efficiency. An electrode surface which is covered with active hydrogenase molecules becomes a promising alternative to platinum for electrochemical hydrogen production. To immobilize the hydrogenase on the electrode, the gold surface was modified by heterobifunctional molecules. A thiol headgroup on one side allowed the binding to the gold surface and the formation of a self-assembled monolayer. The other side of the molecules provided a surface with a high affinity for the hydrogenase CrHydA1 from Chlamydomonas reinhardtii. With methylviologen as a soluble energy carrier, electrons were transferred from carboxy-terminated electrodes to CrHydA1 and conducted to the active site (H-cluster), where they reduce protons to molecular hydrogen. A combined approach of surface-enhanced infrared absorption spectroscopy, gas chromatography, and surface plasmon resonance allowed quantifying the hydrogen production on a molecular level. Hydrogen was produced with a rate of 85 mol H{sub 2} min{sup -1} mol{sup -1}. On a 1'- benzyl-4,4'-bipyridinum (BBP)-terminated surface, the electrons were mediated by the monolayer and no soluble electron carrier was necessary to achieve a comparable hydrogen production rate (approximately 50% of the former system). The hydrogen evolution potential was determined to be -335 mV for the BBP-bound hydrogenase and -290 mV for the hydrogenase which was immobilized on a carboxy-terminated mercaptopropionic acid SAM. Therefore, both systems significantly reduce the hydrogen production overpotential and allow electrochemical hydrogen production at an energy level which is close to the commercially applied platinum electrodes (hydrogen evolution potential of -270 mV). In order to couple hydrogen production and photosynthesis, photosystem I (PS1) from Synechocystis PCC 6803 and membrane-bound hydrogenase (MBH) from Ralstonia eutropha were bound to each other

  9. Biópsia pulmonar cirúrgica em doentes sob ventilação invasiva e com suspeita de doença difusa do parênquima pulmonar Open lung biopsy in patients on mechanical ventilation with suspected diffuse lung disease

    Directory of Open Access Journals (Sweden)

    Natália Melo

    2009-08-01

    Full Text Available Introdução: A realização de biópsia pulmonar cirúrgica (BPC em doentes sob ventilação invasiva (VI no contexto de doenças difusas do pulmão (DPD poderá revelar-se necessária em circunstâncias em que se torne fundamental a precisão diagnóstica, devendo obviamente ser ponderado o risco associado. Objectivo: Avaliação da rentabilidade diagnóstica, alterações da orientação terapêutica, complicações e mortalidade em doentes com DPD sob VI, submetidos a BPC. Material e métodos: Estudo retrospectivo de 19 doen tes admitidos no Hospital de S. João, num período de 8,5 anos (Janeiro 1999 - Julho 2007. Foram analisados os dados demográficos, as variáveis ventilatórias antes e após a BPC, a rentabilidade diagnóstica e o seu efeito na mudança terapêutica e as complicações da BPC. Análise estatística efectuada com SPSS 14.0. Resultados: A idade média dos doentes foi de 58±16,3 anos, e 53% eram do sexo masculino. A média de dias de internamento em unidade de cuidados intensivos (UCI antes da realização da BPC foi de 13±7 dias. Todas as biópsias foram efectuadas por toracotomia. A rentabilidade diagnóstica foi de 95%. Apenas 4 doentes (21% apresentaram complicações deste procedimento (fuga aérea prolongada. A razão pressão parcial do oxigénio arterial/fracção de oxigénio inspirada (PaO2/FiO2 e a pressão expiratória final positiva (PEEP antes e após a BPC não mostraram diferenças significativas. Em 14 doentes (74% o resultado histológico obtido levou à alteração da suspeita de diagnóstico inicial, condicionando em 8 deles (42% uma mudança da orientação terapêutica. A mortalidade global foi de 47% (9 doentes, não se tendo observado em nenhum deles relação com o procedimento. Conclusão: A análise desta amostra sugere que a BPC poderá ser um procedimento de extrema utilidade em situações de diagnóstico indeterminado no contexto de doentes com DPD sob VI, para o que contribui a alta

  10. Doença de Charcot-Marie-Tooth: estudo da biópsia do nervo sural em 41 pacientes Charcot-Marie-Tooth disease: sural nerve biopsy findings in 41 patients

    Directory of Open Access Journals (Sweden)

    Marcos R.G. Freitas

    1995-09-01

    Full Text Available São apresentados os resultados da biópsia do nervo sural à microscopia óptica e eletrônica (ME em 41 pacientes com doença de Charcot-Marie-Tooth (CMT Por estudos de neurocondução prévios nove eram do tipo I e 32 do tipo II. No tipo I, todos tinham grande diminuição do número de fibras, sendo os histogramas do tipo unimodal. Encontramos imagens de desmielinização, remielinização, formação de bulbos de cebola e de regeneração. Um paciente apresentava espessamento da bainha de mielina (atrofia axonal. No tipo II, sete pacientes não apresentavam anomalia à microscopia, com histograma normal. Nos restantes havia discreta a intensa perda de fibras mielínicas principalmente as de grande calibre. Em cinco enfermos havia aumento do número de fibras devido a grande regeneração. Alguns pacientes do tipo II apresentavam à ME imagens de pequenos bulbos de cebola e em um havia também atrofia axonal. Comparando com os dados clínicos e de neurocondução motora, no tipo I não encontramos relação entre a intensidade do quadro clínico e a perda de fibras mielínicas porém houve paralelismo da queda da neurocondução motora e a diminuição do número de fibras. No tipo II não houve relação entre o quadro clínico, a neurocondução e os achados da biópsia nervosa.We studied the pathological findings of sural nerve biopsy in 41 patients with Charcot-Marie-Tooth (CMT disease. They were previously classified by the median motor conduction velocity (MCV in two types. Type I (demyelinating with 9 patients and type II (axonal with 32 cases. In type I we found loss of myelinated fibers (unimodal histogram, demyelinated and remyelinated axons with numerous onion bulb formations. In one case there was thickness of myelin with thin axons (axonal atrophy. In type II there were seven patients with normal sural nerve biopsy. In 25 cases there were mild to severe loss of myelinated fibers. In 5 patients the number of myelinated fibers was

  11. Avaliação de um dispositivo portátil para biópsia vácuo-assistida de microcalcificações mamárias Evaluation of a portable device for vacuum-assisted biopsy of breast microcalcifications

    Directory of Open Access Journals (Sweden)

    Hélio Sebastião Amâncio de Camargo Júnior

    2010-04-01

    Full Text Available OBJETIVO: A biópsia vácuo-assistida é a forma percutânea de biópsia de microcalcificações que obtém a menor taxa de subestimação, porém, seu custo é alto, havendo interesse em se conseguir formas mais baratas de biópsia vácuo-assistida. O objetivo deste trabalho foi testar um dispositivo portátil de biópsia vácuo-assistida que apresenta custo menor. MATERIAIS E MÉTODOS: Foram biopsiadas 35 pacientes que apresentavam agrupamentos de microcalcificações BI-RADS® 4 ou 5. Foram testados a representatividade dos fragmentos colhidos, as dificuldades na reintrodução da cânula e o número de ciclos de colheita. RESULTADOS: Houve obtenção de calcificações representativas em todas as pacientes. Não houve discordância anatomorradiológica, dificuldade na reintrodução da cânula ou complicações graves. CONCLUSÃO: Os dados permitem concluir que o sistema apresenta boa eficácia na obtenção das amostras e com relação de custo-benefício favorável em relação a outros sistemas para a biópsia de microcalcificações, achados em concordância com outras publicações da literatura.OBJECTIVE: Vacuum-assisted biopsy is the percutaneous technique of breast biopsy with the lowest underestimation rate. However, the cost of such procedure is high and currently there is a considerable interest in developing less expensive techniques. The present study was aimed at testing a less expensive device for vacuum-assisted biopsy of breast microcalcifications. MATERIALS AND METHODS: Thirty-five patients with clustered microcalcifications classified as BI-RADS® 4 or 5 were submitted to biopsy. Collected specimen appropriateness, difficulties in the reinsertion of the cannula and number of biopsy passes were evaluated. RESULTS: Successful specimens collection was achieved in all of the patients. Histo-radiological disagreement, difficulties in the cannula reinsertion or severe complications were not observed. CONCLUSION: The authors

  12. Florida Hydrogen Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Block, David L

    2013-06-30

    The Florida Hydrogen Initiative (FHI) was a research, development and demonstration hydrogen and fuel cell program. The FHI program objectives were to develop Florida?s hydrogen and fuel cell infrastructure and to assist DOE in its hydrogen and fuel cell activities The FHI program funded 12 RD&D projects as follows: Hydrogen Refueling Infrastructure and Rental Car Strategies -- L. Lines, Rollins College This project analyzes strategies for Florida's early stage adaptation of hydrogen-powered public transportation. In particular, the report investigates urban and statewide network of refueling stations and the feasibility of establishing a hydrogen rental-car fleet based in Orlando. Methanol Fuel Cell Vehicle Charging Station at Florida Atlantic University ? M. Fuchs, EnerFuel, Inc. The project objectives were to design, and demonstrate a 10 kWnet proton exchange membrane fuel cell stationary power plant operating on methanol, to achieve an electrical energy efficiency of 32% and to demonstrate transient response time of less than 3 milliseconds. Assessment of Public Understanding of the Hydrogen Economy Through Science Center Exhibits, J. Newman, Orlando Science Center The project objective was to design and build an interactive Science Center exhibit called: ?H2Now: the Great Hydrogen Xchange?. On-site Reformation of Diesel Fuel for Hydrogen Fueling Station Applications ? A. Raissi, Florida Solar Energy Center This project developed an on-demand forecourt hydrogen production technology by catalytically converting high-sulfur hydrocarbon fuels to an essentially sulfur-free gas. The removal of sulfur from reformate is critical since most catalysts used for the steam reformation have limited sulfur tolerance. Chemochromic Hydrogen Leak Detectors for Safety Monitoring ? N. Mohajeri and N. Muradov, Florida Solar Energy Center This project developed and demonstrated a cost-effective and highly selective chemochromic (visual) hydrogen leak detector for safety

  13. Hydrogen Recovery System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Liquid hydrogen is used extensively by NASA to support cryogenic rocket testing. In addition, there are many commercial applications in which delivery and use of...

  14. Hydrogen Recovery System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Rocket test operations at NASA Stennis Space Center (SSC) result in substantial quantities of hydrogen gas that is flared from the facility and helium gas that is...

  15. Photoelectrochemical hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Rocheleau, R.E.; Miller, E.; Misra, A. [Univ. of Hawaii, Honolulu, HI (United States)

    1996-10-01

    The large-scale production of hydrogen utilizing energy provided by a renewable source to split water is one of the most ambitious long-term goals of the U.S. Department of Energy`s Hydrogen Program. One promising option to meet this goal is direct photoelectrolysis in which light absorbed by semiconductor-based photoelectrodes produces electrical power internally to split water into hydrogen and oxygen. Under this program, direct solar-to-chemical conversion efficiencies as high as 7.8 % have been demonstrated using low-cost, amorphous-silicon-based photoelectrodes. Detailed loss analysis models indicate that solar-to-chemical conversion greater than 10% can be achieved with amorphous-silicon-based structures optimized for hydrogen production. In this report, the authors describe the continuing progress in the development of thin-film catalytic/protective coatings, results of outdoor testing, and efforts to develop high efficiency, stable prototype systems.

  16. Water's Hydrogen Bond Strength

    CERN Document Server

    Chaplin, Martin

    2007-01-01

    Water is necessary both for the evolution of life and its continuance. It possesses particular properties that cannot be found in other materials and that are required for life-giving processes. These properties are brought about by the hydrogen bonded environment particularly evident in liquid water. Each liquid water molecule is involved in about four hydrogen bonds with strengths considerably less than covalent bonds but considerably greater than the natural thermal energy. These hydrogen bonds are roughly tetrahedrally arranged such that when strongly formed the local clustering expands, decreasing the density. Such low density structuring naturally occurs at low and supercooled temperatures and gives rise to many physical and chemical properties that evidence the particular uniqueness of liquid water. If aqueous hydrogen bonds were actually somewhat stronger then water would behave similar to a glass, whereas if they were weaker then water would be a gas and only exist as a liquid at sub-zero temperature...

  17. Thin film hydrogen sensor

    Science.gov (United States)

    Lauf, R.J.; Hoffheins, B.S.; Fleming, P.H.

    1994-11-22

    A hydrogen sensor element comprises an essentially inert, electrically-insulating substrate having a thin-film metallization deposited thereon which forms at least two resistors on the substrate. The metallization comprises a layer of Pd or a Pd alloy for sensing hydrogen and an underlying intermediate metal layer for providing enhanced adhesion of the metallization to the substrate. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors, and at least one of the resistors is left uncovered. The difference in electrical resistances of the covered resistor and the uncovered resistor is related to hydrogen concentration in a gas to which the sensor element is exposed. 6 figs.

  18. Experts’ understanding of partial derivatives using the partial derivative machine

    Directory of Open Access Journals (Sweden)

    David Roundy

    2015-09-01

    Full Text Available [This paper is part of the Focused Collection on Upper Division Physics Courses.] Partial derivatives are used in a variety of different ways within physics. Thermodynamics, in particular, uses partial derivatives in ways that students often find especially confusing. We are at the beginning of a study of the teaching of partial derivatives, with a goal of better aligning the teaching of multivariable calculus with the needs of students in STEM disciplines. In this paper, we report on an initial study of expert understanding of partial derivatives across three disciplines: physics, engineering, and mathematics. We report on the central research question of how disciplinary experts understand partial derivatives, and how their concept images of partial derivatives differ, with a focus on experimentally measured quantities. Using the partial derivative machine (PDM, we probed expert understanding of partial derivatives in an experimental context without a known functional form. In particular, we investigated which representations were cued by the experts’ interactions with the PDM. Whereas the physicists and engineers were quick to use measurements to find a numeric approximation for a derivative, the mathematicians repeatedly returned to speculation as to the functional form; although they were comfortable drawing qualitative conclusions about the system from measurements, they were reluctant to approximate the derivative through measurement. On a theoretical front, we found ways in which existing frameworks for the concept of derivative could be expanded to include numerical approximation.

  19. An alternative near-neighbor definition of hydrogen bonding in water.

    Science.gov (United States)

    Hammerich, A D; Buch, V

    2008-03-21

    A definition of hydrogen bonding in water is proposed in which an H...O pair forms a hydrogen bond if (a) an oxygen atom is the nearest nonchemically bonded neighbor of a hydrogen atom; and (b) the hydrogen is the first or the second intermolecular near-neighbor of the oxygen. Unlike the commonly employed hydrogen-bond definitions, this definition does not depend on the choice of geometric or energetic cutoffs applied to continuous distributions of properties. With the present definition, the distribution of O...H bond lengths decays smoothly to zero in a physically reasonable range. After correction for the presence of intermittent hydrogen bonds, this definition appears to provide a more stable description of hydrogen bonds and coordination shells than the more conventional cutoff-based definition. "Partial" H bonds satisfying only one of the two bonding requirements serve as transition states in the H-bond network evolution.

  20. Current Development in Treatment and Hydrogen Energy Conversion of Organic Solid Waste

    Science.gov (United States)

    Shin, Hang-Sik

    2008-02-01

    This manuscript summarized current developments on continuous hydrogen production technologies researched in Korea advanced institute of science and technology (KAIST). Long-term continuous pilot-scale operation of hydrogen producing processes fed with non-sterile food waste exhibited successful results. Experimental findings obtained by the optimization processes of growth environments for hydrogen producing bacteria, the development of high-rate hydrogen producing strategies, and the feasibility tests for real field application could contribute to the progress of fermentative hydrogen production technologies. Three major technologies such as controlling dilution rate depending on the progress of acidogenesis, maintaining solid retention time independently from hydraulic retention time, and decreasing hydrogen partial pressure by carbon dioxide sparging could enhance hydrogen production using anaerobic leaching beds reactors and anaerobic sequencing batch reactors. These findings could contribute to stable, reliable and effective performances of pilot-scale reactors treating organic wastes.

  1. Test results from a simple, low-cost, pressure-fed liquid hydrogen/liquid oxygen rocket combustor

    Science.gov (United States)

    Dressler, G. A.; Stoddard, F. J.; Gavitt, K. R.; Klem, M. D.

    1993-01-01

    A simple, low-cost rocket engine was designed, fabricated, and successfully hot fire tested over a wide range of interface conditions and operating parameters. The engine used low enthalpy hydrogen (45 to 70 R, 200 to 390 psia) and oxygen (139 to 163 R, 210 to 480 psia) propellants pressure-fed directly from facility cryogenic tanks. The engine demonstrated excellent performance, with 97% average combustion efficiency, and absence of combustion instabilities. Engine design chamber pressure was 300 psia, yielding about 16,500 pounds thrust at sea level with a 3:1 expansion ration test nozzle. The engine used a fixed-element injector based on TRW's unique coaxial pintle design, but was operated at 60%, 80%, and 100% thrust levels by throttling facility propellant valves. The engine was tested at propellant mixture ratios (O/F) from 5.8 to 8.4; design O/F was 6.6. To document combustion stability, in five tests RDX explosive pulse guns were detonated in radial and tangential directions across the combustion chamber during steady-state operation. The largest disturbance consisted of simultaneous detonation of a 20-grain radial gun and a 40-grain tangential gun. In no case was an instability, either feed system mode or chamber acoustic mode, excited. High-frequency piezoelectric pressure transducers documented stable recovery from disturbance overpressures within 40 milliseconds of peak pressure. A total of 67 firing tests, accumulating 149 seconds of firing time above 10% P(sub c), were performed. Since parametric testing required run durations of only 2 to 3 seconds, a heat sink combustion chamber was employed for most runs. To evaluate the feasibility of a low-cost ablative system for a flight engine design, one 20-second continuous firing was conducted with a silicone rubber chamber/throat/nozzle liner cast in one piece directly into the engine. The ablative engine operated at the equivalent of 309 seconds sea level specific impulse, when adjusted to a 98% efficient

  2. Test results from a simple, low-cost, pressure-fed liquid hydrogen/liquid oxygen rocket combustor

    Science.gov (United States)

    Dressler, G. A.; Stoddard, F. J.; Gavitt, K. R.; Klem, M. D.

    1993-11-01

    A simple, low-cost rocket engine was designed, fabricated, and successfully hot fire tested over a wide range of interface conditions and operating parameters. The engine used low enthalpy hydrogen (45 to 70 R, 200 to 390 psia) and oxygen (139 to 163 R, 210 to 480 psia) propellants pressure-fed directly from facility cryogenic tanks. The engine demonstrated excellent performance, with 97% average combustion efficiency, and absence of combustion instabilities. Engine design chamber pressure was 300 psia, yielding about 16,500 pounds thrust at sea level with a 3:1 expansion ration test nozzle. The engine used a fixed-element injector based on TRW's unique coaxial pintle design, but was operated at 60%, 80%, and 100% thrust levels by throttling facility propellant valves. The engine was tested at propellant mixture ratios (O/F) from 5.8 to 8.4; design O/F was 6.6. To document combustion stability, in five tests RDX explosive pulse guns were detonated in radial and tangential directions across the combustion chamber during steady-state operation. The largest disturbance consisted of simultaneous detonation of a 20-grain radial gun and a 40-grain tangential gun. In no case was an instability, either feed system mode or chamber acoustic mode, excited. High-frequency piezoelectric pressure transducers documented stable recovery from disturbance overpressures within 40 milliseconds of peak pressure. A total of 67 firing tests, accumulating 149 seconds of firing time above 10% P(sub c), were performed. Since parametric testing required run durations of only 2 to 3 seconds, a heat sink combustion chamber was employed for most runs. To evaluate the feasibility of a low-cost ablative system for a flight engine design, one 20-second continuous firing was conducted with a silicone rubber chamber/throat/nozzle liner cast in one piece directly into the engine. The ablative engine operated at the equivalent of 309 seconds sea level specific impulse, when adjusted to a 98% efficient

  3. The hydrogen issue.

    Science.gov (United States)

    Armaroli, Nicola; Balzani, Vincenzo

    2011-01-17

    Hydrogen is often proposed as the fuel of the future, but the transformation from the present fossil fuel economy to a hydrogen economy will need the solution of numerous complex scientific and technological issues, which will require several decades to be accomplished. Hydrogen is not an alternative fuel, but an energy carrier that has to be produced by using energy, starting from hydrogen-rich compounds. Production from gasoline or natural gas does not offer any advantage over the direct use of such fuels. Production from coal by gasification techniques with capture and sequestration of CO₂ could be an interim solution. Water splitting by artificial photosynthesis, photobiological methods based on algae, and high temperatures obtained by nuclear or concentrated solar power plants are promising approaches, but still far from practical applications. In the next decades, the development of the hydrogen economy will most likely rely on water electrolysis by using enormous amounts of electric power, which in its turn has to be generated. Producing electricity by burning fossil fuels, of course, cannot be a rational solution. Hydroelectric power can give but a very modest contribution. Therefore, it will be necessary to generate large amounts of electric power by nuclear energy of by renewable energies. A hydrogen economy based on nuclear electricity would imply the construction of thousands of fission reactors, thereby magnifying all the problems related to the use of nuclear energy (e.g., safe disposal of radioactive waste, nuclear proliferation, plant decommissioning, uranium shortage). In principle, wind, photovoltaic, and concentrated solar power have the potential to produce enormous amounts of electric power, but, except for wind, such technologies are too underdeveloped and expensive to tackle such a big task in a short period of time. A full development of a hydrogen economy needs also improvement in hydrogen storage, transportation and distribution

  4. Hepatobiliary alterations in massive biliary ascariasis: histopathological aspects of an autopsy case Lesões hepatobiliares em ascaridíase biliar maciça: aspectos histopatológicos em um caso de autópsia

    Directory of Open Access Journals (Sweden)

    Luiz Carlos da Costa Gayotto

    1990-04-01

    Full Text Available Hepatobiliary alterations found in an autopsy case of massive Biliary Ascariasis, are reported on histological grounds. Severe cholangitis was the main finding, but other changes were also detected, such as pyloric and intestinal metaplasia, hyperplasia of the epithelial lining, with intraductal papillomas and adenomatous proliferation. Remnants of the worm were observed tightly adhered to the epithelium, forming microscopic intrahepatic calculi. Mucopolysaccharides, especially acid, showed to be strongly positive on the luminal border, and in proliferated glands around the ducts. The authors discuss the similarity between such findings and Oriental Cholangiohepatitis, and suggest that inflammation and the presence of the parasitic remnants are responsible for the hyperplastic and metaplastic changes, similarly with what occurs in chlonorchiasis, fascioliasis and schistosomiasis.Os autores apresentam os aspectos histopatológicos encontrados no fígado de um caso de autópsia de Ascaridíase Biliar maciça. A intensa colangite foi o aspecto predominante, mas outras lesões também foram encontradas, tais como metaplasia pilórica e intestinal, hiperplasia epitelial com papilomas intraductais, e por vezes padrão adenomatoso. Restos do helminto foram encontrados fortemente aderidos ao epitélio, sendo intensa a positividade de mucopolissacárides, principalmente ácidos, na borda luminal do epitélio ductal e em glândulas proliferadas ao redor dos ductos. Os autores discutem a semelhança da Ascaridíase Biliar com a Colangio Hepatite Oriental, e sugerem que o processo inflamatório e a presença de restos do verme são responsáveis pelas alterações hiperplásicas e metaplásicas, analogamente ao que ocorre na clonorquíase, fasciolíase e esquistossomose.

  5. Exame imuno-histoquímico na biópsia de medula óssea: uma importante ferramenta complementar à morfologia Immunohistochemistry in bone marrow biopsy: an important complementary tool for morphology

    Directory of Open Access Journals (Sweden)

    Maria Cláudia Nogueira Zerbini

    2011-12-01

    Full Text Available Por razões técnicas e históricas, a utilização da imuno-histoquímica (IHQ em biópsias de medula óssea (BMO levou algum tempo a ocupar espaço na avaliação diagnóstica desse tipo de material. Entretanto, esse cenário vem se modificando graças ao crescimento exponencial do número de anticorpos disponíveis para a utilização em material incluído em parafina, além do aperfeiçoamento das técnicas de recuperação antigênica e descalcificação do material. Este texto tem a finalidade de auxiliar o patologista na seleção/ interpretação de painéis de anticorpos utilizados nos laboratórios de rotina, de acordo com a experiência do autor, assim como de enumerar referências da literatura de grande utilidade para a prática diagnóstica.Due to historical and technical reasons, the use of immunohistochemistry (IHC in bone marrow biopsies (BMB has not till recently been introduced in diagnostic evaluation. However, this scenario has changed owing to the exponential growth in the number of antibodies available for paraffin-embedded material and the development of techniques for antigen retrieval and material decalcification. Not only does this text aim to assist pathologists in the selection/interpretation of antibody panels used in routine laboratories, but it also lists literature references highly useful for diagnostic practice in accordance with the author's experience.

  6. Cryogenic hydrogen release research.

    Energy Technology Data Exchange (ETDEWEB)

    LaFleur, Angela Christine [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-12-01

    The objective of this project was to devolop a plan for modifying the Turbulent Combustion Laboratory (TCL) with the necessary infrastructure to produce a cold (near liquid temperature) hydrogen jet. The necessary infrastructure has been specified and laboratory modifications are currently underway. Once complete, experiments from this platform will be used to develop and validate models that inform codes and standards which specify protection criteria for unintended releases from liquid hydrogen storage, transport, and delivery infrastructure.

  7. Purdue Hydrogen Systems Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Jay P Gore; Robert Kramer; Timothee L Pourpoint; P. V. Ramachandran; Arvind Varma; Yuan Zheng

    2011-12-28

    The Hydrogen Systems Laboratory in a unique partnership between Purdue University's main campus in West Lafayette and the Calumet campus was established and its capabilities were enhanced towards technology demonstrators. The laboratory engaged in basic research in hydrogen production and storage and initiated engineering systems research with performance goals established as per the USDOE Hydrogen, Fuel Cells, and Infrastructure Technologies Program. In the chemical storage and recycling part of the project, we worked towards maximum recycling yield via novel chemical selection and novel recycling pathways. With the basic potential of a large hydrogen yield from AB, we used it as an example chemical but have also discovered its limitations. Further, we discovered alternate storage chemicals that appear to have advantages over AB. We improved the slurry hydrolysis approach by using advanced slurry/solution mixing techniques. We demonstrated vehicle scale aqueous and non-aqueous slurry reactors to address various engineering issues in on-board chemical hydrogen storage systems. We measured the thermal properties of raw and spent AB. Further, we conducted experiments to determine reaction mechanisms and kinetics of hydrothermolysis in hydride-rich solutions and slurries. We also developed a continuous flow reactor and a laboratory scale fuel cell power generation system. The biological hydrogen production work summarized as Task 4.0 below, included investigating optimal hydrogen production cultures for different substrates, reducing the water content in the substrate, and integrating results from vacuum tube solar collector based pre and post processing tests into an enhanced energy system model. An automated testing device was used to finalize optimal hydrogen production conditions using statistical procedures. A 3 L commercial fermentor (New Brunswick, BioFlo 115) was used to finalize testing of larger samples and to consider issues related to scale up

  8. Cytosinium hydrogen selenite

    Directory of Open Access Journals (Sweden)

    Radhwane Takouachet

    2014-02-01

    Full Text Available In the crystal structure of the title salt, C4H6N3O+·HSeO3−, systematic name 6-amino-2-methylidene-2,3-dihydropyrimidin-1-ium hydrogen selenite, the hydrogenselenite anions and the cytosinium cations are linked via N—H...O, N—H...Se, O—H...O, O—H··Se and C—H...O hydrogen bonds, forming a three-dimensional framework.

  9. Hydrogen Delivery Technical Team Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-06-01

    The mission of the Hydrogen Delivery Technical Team (HDTT) is to enable the development of hydrogen delivery technologies, which will allow for fuel cell competitiveness with gasoline and hybrid technologies by achieving an as-produced, delivered, and dispensed hydrogen cost of $2-$4 per gallon of gasoline equivalent of hydrogen.

  10. Hydrogen Sorption and Transport

    Science.gov (United States)

    McNeece, C. J.; Hesse, M. A.

    2015-12-01

    Hydrogen is unique among aqueous ions, both in its importance for geochemical reactions, and in its complex transport behavior through reactive media. The structure of hydrogen reaction fronts can be analyzed in the advective limit of the transport equation. At local chemical equilibrium, sorption of hydrogen onto the media surface (sorption isotherm) controls reaction front morphology. Transport modeling thus necessitates accurate knowledge of surface chemistry. Though motivated by transport, sorption models are often parameterized against batch titration experiments. The validity of these parameterizations, in a transport setting, are seldom tested. The analytic solution to the transport equation gives an algebraic relationship between concentration velocity and equilibrium sorption behavior. In this study, we conduct a suite of column flow experiments through quartz sand. Hydrogen concentration breakthrough curves at the column outlet are used to infer the "transport sorption isotherm." These results are compared to the batch titration derived sorption isotherm. We find excellent agreement between the datasets. Our findings suggest that, for aqueous hydrogen, local chemical equilibrium is a valid assumption. With the goal of a predictive transport model, we parameterize various sorption models against this dataset. Models which incorporate electrostatic effects at the surface predict transport well. Nonelectrostatic models such as the Kd, Langmuir, and Freundlich models fail. These results are particularly compelling as nonelectrostatic models are often employed to predict hydrogen transport in many reactive transport code.

  11. Electrochemical hydrogen Storage Systems

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Digby Macdonald

    2010-08-09

    As the global need for energy increases, scientists and engineers have found a possible solution by using hydrogen to power our world. Although hydrogen can be combusted as a fuel, it is considered an energy carrier for use in fuel cells wherein it is consumed (oxidized) without the production of greenhouse gases and produces electrical energy with high efficiency. Chemical storage of hydrogen involves release of hydrogen in a controlled manner from materials in which the hydrogen is covalently bound. Sodium borohydride and aminoborane are two materials given consideration as chemical hydrogen storage materials by the US Department of Energy. A very significant barrier to adoption of these materials as hydrogen carriers is their regeneration from 'spent fuel,' i.e., the material remaining after discharge of hydrogen. The U.S. Department of Energy (DOE) formed a Center of Excellence for Chemical Hydrogen Storage, and this work stems from that project. The DOE has identified boron hydrides as being the main compounds of interest as hydrogen storage materials. The various boron hydrides are then oxidized to release their hydrogen, thereby forming a 'spent fuel' in the form of a lower boron hydride or even a boron oxide. The ultimate goal of this project is to take the oxidized boron hydrides as the spent fuel and hydrogenate them back to their original form so they can be used again as a fuel. Thus this research is essentially a boron hydride recycling project. In this report, research directed at regeneration of sodium borohydride and aminoborane is described. For sodium borohydride, electrochemical reduction of boric acid and sodium metaborate (representing spent fuel) in alkaline, aqueous solution has been investigated. Similarly to literature reports (primarily patents), a variety of cathode materials were tried in these experiments. Additionally, approaches directed at overcoming electrostatic repulsion of borate anion from the cathode, not

  12. Examining hydrogen transitions.

    Energy Technology Data Exchange (ETDEWEB)

    Plotkin, S. E.; Energy Systems

    2007-03-01

    This report describes the results of an effort to identify key analytic issues associated with modeling a transition to hydrogen as a fuel for light duty vehicles, and using insights gained from this effort to suggest ways to improve ongoing modeling efforts. The study reported on here examined multiple hydrogen scenarios reported in the literature, identified modeling issues associated with those scenario analyses, and examined three DOE-sponsored hydrogen transition models in the context of those modeling issues. The three hydrogen transition models are HyTrans (contractor: Oak Ridge National Laboratory), MARKAL/DOE* (Brookhaven National Laboratory), and NEMS-H2 (OnLocation, Inc). The goals of these models are (1) to help DOE improve its R&D effort by identifying key technology and other roadblocks to a transition and testing its technical program goals to determine whether they are likely to lead to the market success of hydrogen technologies, (2) to evaluate alternative policies to promote a transition, and (3) to estimate the costs and benefits of alternative pathways to hydrogen development.

  13. Hydrogen supplies for SPFC vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Hart, D.; Bauen, A.; Fouquet, R.; Leach, M.; Pearson, P.; Anderson, D.

    2000-07-01

    This report summarises the findings of a study investigating the potential of using hydrogen fuel for fuel cell-powered fleet vehicles based at a depot in a range of counties. An overview of current hydrogen supply and demand is presented, and research already carried out on potential hydrogen refuelling infrastructures, and the costs of producing hydrogen as a transportation fuel are examined. Hydrogen demand modelling, and supplying hydrogen to fleet vehicles, alternative hydrogen supply options, energy and emissions comparison with competing fuels, and health and safety standards are discussed.

  14. Algorithms over partially ordered sets

    DEFF Research Database (Denmark)

    Baer, Robert M.; Østerby, Ole

    1969-01-01

    We here study some problems concerned with the computational analysis of finite partially ordered sets. We begin (in § 1) by showing that the matrix representation of a binary relationR may always be taken in triangular form ifR is a partial ordering. We consider (in § 2) the chain structure...

  15. [Acrylic resin removable partial dentures

    NARCIS (Netherlands)

    Baat, C. de; Witter, D.J.; Creugers, N.H.J.

    2011-01-01

    An acrylic resin removable partial denture is distinguished from other types of removable partial dentures by an all-acrylic resin base which is, in principle, solely supported by the edentulous regions of the tooth arch and in the maxilla also by the hard palate. When compared to the other types of

  16. Partial Epilepsy with Auditory Features

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-07-01

    Full Text Available The clinical characteristics of 53 sporadic (S cases of idiopathic partial epilepsy with auditory features (IPEAF were analyzed and compared to previously reported familial (F cases of autosomal dominant partial epilepsy with auditory features (ADPEAF in a study at the University of Bologna, Italy.

  17. California Hydrogen Infrastructure Project

    Energy Technology Data Exchange (ETDEWEB)

    Heydorn, Edward C

    2013-03-12

    Air Products and Chemicals, Inc. has completed a comprehensive, multiyear project to demonstrate a hydrogen infrastructure in California. The specific primary objective of the project was to demonstrate a model of a real-world retail hydrogen infrastructure and acquire sufficient data within the project to assess the feasibility of achieving the nation's hydrogen infrastructure goals. The project helped to advance hydrogen station technology, including the vehicle-to-station fueling interface, through consumer experiences and feedback. By encompassing a variety of fuel cell vehicles, customer profiles and fueling experiences, this project was able to obtain a complete portrait of real market needs. The project also opened its stations to other qualified vehicle providers at the appropriate time to promote widespread use and gain even broader public understanding of a hydrogen infrastructure. The project engaged major energy companies to provide a fueling experience similar to traditional gasoline station sites to foster public acceptance of hydrogen. Work over the course of the project was focused in multiple areas. With respect to the equipment needed, technical design specifications (including both safety and operational considerations) were written, reviewed, and finalized. After finalizing individual equipment designs, complete station designs were started including process flow diagrams and systems safety reviews. Material quotes were obtained, and in some cases, depending on the project status and the lead time, equipment was placed on order and fabrication began. Consideration was given for expected vehicle usage and station capacity, standard features needed, and the ability to upgrade the station at a later date. In parallel with work on the equipment, discussions were started with various vehicle manufacturers to identify vehicle demand (short- and long-term needs). Discussions included identifying potential areas most suited for hydrogen fueling

  18. Hydrogen storage and generation system

    Science.gov (United States)

    Dentinger, Paul M.; Crowell, Jeffrey A. W.

    2010-08-24

    A system for storing and generating hydrogen generally and, in particular, a system for storing and generating hydrogen for use in an H.sub.2/O.sub.2 fuel cell. The hydrogen storage system uses the beta particles from a beta particle emitting material to degrade an organic polymer material to release substantially pure hydrogen. In a preferred embodiment of the invention, beta particles from .sup.63Ni are used to release hydrogen from linear polyethylene.

  19. Hydrogen as an energy vector

    OpenAIRE

    Valenzuela Ortega, Daniel

    2013-01-01

    Study of the use of the Hydrogen to storage big amounts of energy. In this project there will be an study about the different energies that are profitable to use them to obtain hydrogen, the study of the different technologies to obtain hydrogen (electrolysis, gasification, etc.), the study of the technologies for storage the hydrogen and the study of the different ways to obtain final energy with the hydrogen. There will be also an overall analysis of the efficiency of the process a...

  20. The phenomenon of runaway electrons in partially ionized non-ideal plasma

    Energy Technology Data Exchange (ETDEWEB)

    Ramazanov, T S; Turekhanova, K M [IETP, Al Farabi Kazakh National University, Tole Bi 96a, 050012 Almaty (Kazakhstan)], E-mail: kunduz@physics.kz

    2009-05-29

    The effect of runaway electrons in partially ionized hydrogen plasma is investigated on the basis of pseudopotential models. The conditions of runaway electrons were determined. Dependences of an electron free path on the plasma density and coupling parameter were obtained. It is shown that if the quantum-mechanical and screening effects in non-ideal partially ionized plasma are taken into consideration, the collision frequency curve for electrons has maxima and free path curves for electrons have minima.

  1. Experimental Demonstration of Advanced Palladium Membrane Separators for Central High Purity Hydrogen Production

    Energy Technology Data Exchange (ETDEWEB)

    Sean Emerson; Neal Magdefrau; Susanne Opalka; Ying She; Catherine Thibaud-Erkey; Thoman Vanderspurt; Rhonda Willigan

    2010-06-30

    The overall objectives for this project were to: (1) confirm the high stability and resistance of a PdCu trimetallic alloy to carbon and carbide formation and, in addition, resistance to sulfur, halides, and ammonia; (2) develop a sulfur, halide, and ammonia resistant alloy membrane with a projected hydrogen permeance of 25 m{sup 3}m{sup -2}atm{sup -0.5}h{sup -1} at 400 C and capable of operating at pressures of 12.1 MPa ({approx}120 atm, 1750 psia); and (3) construct and experimentally validate the performance of 0.1 kg/day H{sup 2} PdCu trimetallic alloy membrane separators at feed pressures of 2 MPa (290 psia) in the presence of H{sub 2}S, NH{sub 3}, and HCl. This project successfully increased the technology readiness level of palladium-based metallic membranes for hydrogen separation from coal-biomass gasifier exhaust or similar hydrogen-containing gas streams. The reversible tolerance of palladium-copper (PdCu) alloys was demonstrated for H{sub 2}S concentrations varying from 20 ppmv up to 487 ppmv and NH{sub 3} concentrations up to 9 ppmv. In addition, atomistic modeling validated the resistance of PdCu alloys to carbon formation, irreversible sulfur corrosion, and chlorine attack. The experimental program highlighted two key issues which must be addressed as part of future experimental programs: (1) tube defects and (2) non-membrane materials of construction. Four out of five FCC PdCu separators developed leaks during the course of the experimental program because {approx}10% of the alloy tubes contained a single defect that resulted in a thin, weak point in the tube walls. These defects limited operation of the existing tubes to less than 220 psig. For commercial applications of a PdCu alloy hydrogen separator under high sulfur concentrations, it was determined that stainless steel 316 is not suitable for housing or supporting the device. Testing with sulfur concentrations of 487 {+-} 4 ppmv resulted in severe corrosion of the stainless steel components of

  2. Cast Partial Denture versus Acrylic Partial Denture for Replacement of Missing Teeth in Partially Edentulous Patients

    Directory of Open Access Journals (Sweden)

    Pramita Suwal

    2017-03-01

    Full Text Available Aim: To compare the effects of cast partial denture with conventional all acrylic denture in respect to retention, stability, masticatory efficiency, comfort and periodontal health of abutments. Methods: 50 adult partially edentulous patient seeking for replacement of missing teeth having Kennedy class I and II arches with or without modification areas were selected for the study. Group-A was treated with cast partial denture and Group-B with acrylic partial denture. Data collected during follow-up visit of 3 months, 6 months, and 1 year by evaluating retention, stability, masticatory efficiency, comfort, periodontal health of abutment. Results: Chi-square test was applied to find out differences between the groups at 95% confidence interval where p = 0.05. One year comparison shows that cast partial denture maintained retention and stability better than acrylic partial denture (p< 0.05. The masticatory efficiency was significantly compromising from 3rd month to 1 year in all acrylic partial denture groups (p< 0.05. The comfort of patient with cast partial denture was maintained better during the observation period (p< 0.05. Periodontal health of abutment was gradually deteriorated in all acrylic denture group (p

  3. Hydrogen Contractors Meeting

    Energy Technology Data Exchange (ETDEWEB)

    Fitzsimmons, Tim [Dept. of Energy (DOE), Washington DC (United States). Office of Basic Energy Sciences. Division of Materials Sciences and Engineering

    2006-05-16

    This volume highlights the scientific content of the 2006 Hydrogen Contractors Meeting sponsored by the Division of Materials Sciences and Engineering (DMS&E) on behalf of the Office of Basic Energy Sciences (BES) of the U. S. Department of Energy (DOE). Hydrogen Contractors Meeting held from May 16-19, 2006 at the Crystal Gateway Marriott Hotel Arlington, Virginia. This meeting is the second in a series of research theme-based Contractors Meetings sponsored by DMS&E held in conjunction with our counterparts in the Office of Energy Efficiency and Renewable Energy (EERE) and the first with the Hydrogen, Fuel Cells and Infrastructure Technologies Program. The focus of this year’s meeting is BES funded fundamental research underpinning advancement of hydrogen storage. The major goals of these research efforts are the development of a fundamental scientific base in terms of new concepts, theories and computational tools; new characterization capabilities; and new materials that could be used or mimicked in advancing capabilities for hydrogen storage.

  4. Hot Hydrogen Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    W. David Swank

    2007-02-01

    The core in a nuclear thermal rocket will operate at high temperatures and in hydrogen. One of the important parameters in evaluating the performance of a nuclear thermal rocket is specific impulse, ISp. This quantity is proportional to the square root of the propellant’s absolute temperature and inversely proportional to square root of its molecular weight. Therefore, high temperature hydrogen is a favored propellant of nuclear thermal rocket designers. Previous work has shown that one of the life-limiting phenomena for thermal rocket nuclear cores is mass loss of fuel to flowing hydrogen at high temperatures. The hot hydrogen test facility located at the Idaho National Lab (INL) is designed to test suitability of different core materials in 2500°C hydrogen flowing at 1500 liters per minute. The facility is intended to test non-uranium containing materials and therefore is particularly suited for testing potential cladding and coating materials. In this first installment the facility is described. Automated Data acquisition, flow and temperature control, vessel compatibility with various core geometries and overall capabilities are discussed.

  5. The hydrogen laminar jet

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Sanz, M. [Departamento de Motopropulsion y Termofluidomecanica, ETSI Aeronauticos, Universidad Politecnica de Madrid, 28040 Madrid (Spain); Rosales, M. [Department Ingenieria Termica y de Fluidos, Universidad Carlos III de Madrid, 28911, Leganes (Spain); Instituto de Innovacion en Mineria y Metalurgia, Avenida del Valle 738, Santiago (Chile); Sanchez, A.L. [Department Ingenieria Termica y de Fluidos, Universidad Carlos III de Madrid, 28911, Leganes (Spain)

    2010-04-15

    Numerical and asymptotic methods are used to investigate the structure of the hydrogen jet discharging into a quiescent air atmosphere. The analysis accounts in particular for the variation of the density and transport properties with composition. The Reynolds number of the flow R{sub j}, based on the initial jet radius a, the density {rho}{sub j} and viscosity {mu}{sub j} of the jet and the characteristic jet velocity u{sub j}, is assumed to take moderately large values, so that the jet remains slender and stable, and can be correspondingly described by numerical integration of the continuity, momentum and species conservation equations written in the boundary-layer approximation. The solution for the velocity and composition in the jet development region of planar and round jets, corresponding to streamwise distances of order R{sub j}a, is computed numerically, along with the solutions that emerge both in the near field and in the far field. The small value of the hydrogen-to-air molecular weight ratio is used to simplify the solution by considering the asymptotic limit of vanishing jet density. The development provides at leading-order explicit analytical expressions for the far-field velocity and hydrogen mass fraction that describe accurately the hydrogen jet near the axis. The information provided can be useful in particular to characterize hydrogen discharge processes from holes and cracks. (author)

  6. Hydrogen in Martian Meteorites

    Science.gov (United States)

    Peslier, A. H.; Hervig, R.; Irving, T.

    2017-01-01

    Most volatile studies of Mars have targeted its surface via spacecraft and rover data, and have evidenced surficial water in polar caps and the atmosphere, in the presence of river channels, and in the detection of water bearing minerals. The other focus of Martian volatile studies has been on Martian meteorites which are all from its crust. Most of these studies are on hydrous phases like apatite, a late-stage phase, i.e. crystallizing near the end of the differentiation sequence of Martian basalts and cumulates. Moreover, calculating the water content of the magma a phosphate crystallized from is not always possible, and yet is an essential step to estimate how much water was present in a parent magma and its source. Water, however, is primarily dissolved in the interiors of differentiated planets as hydrogen in lattice defects of nominally anhydrous minerals (olivine, pyroxene, feldspar) of the crust and mantle. This hydrogen has tremendous influence, even in trace quantities, on a planet's formation, geodynamics, cooling history and the origin of its volcanism and atmosphere as well as its potential for life. Studies of hydrogen in nominally anhydrous phases of Martian meteorites are rare. Measuring water contents and hydrogen isotopes in well-characterized nominally anhydrous minerals of Martian meteorites is the goal of our study. Our work aims at deciphering what influences the distribution and origin of hydrogen in Martian minerals, such as source, differentiation, degassing and shock.

  7. Microfabricated hydrogen sensitive membranes

    Energy Technology Data Exchange (ETDEWEB)

    Naddaf, A.; Kraetz, L. [Lehrstuhl fuer Thermische Verfahrenstechnik, Technische Universitaet Kaiserslautern (Germany); Detemple, P.; Schmitt, S.; Hessel, V. [Institut fuer Mikrotechnik Mainz GmbH, Mainz (Germany); Faqir, N. [University of Jordan, Amman (Jordan); Bart, H.J.

    2009-01-15

    Thin, defect-free palladium, palladium/copper and palladium/silver hydrogen absorbing membranes were microfabricated. A dual sputtering technique was used to deposit the palladium alloy membranes of only 1 {mu}m thickness on a nonporous silicon substrate. Advanced silicon etching (ASE) was applied on the backside to create a mechanically stable support structure for the thin films. Performance evaluation was carried out for different gases in a temperature range of 20 C to 298 C at a constant differential pressure of 110 kPa at the two sides of the membrane. The composite membranes show an excellent permeation rate of hydrogen, which appears to be 0.05 Pa m{sup 3} s{sup -1} and 0.01.10{sup -3} Pa m{sup 3} s{sup -1} at 20 C for the microfabricated 23 % silver and the 53 % copper composite membranes, respectively. The selectivity to hydrogen over a gas mixture containing, in addition to hydrogen, carbon monoxide, carbon dioxide and nitrogen was measured. The mass spectrometer did not detect any CO{sub 2} or CO, showing that the membrane is completely hydrogen selective. The microfabricated membranes exhibit both high mechanical strength (they easily withstand pressures up to 4 bar) and high thermal stability (up to 650 C). (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  8. Partial order infinitary term rewriting

    DEFF Research Database (Denmark)

    Bahr, Patrick

    2014-01-01

    with the partial order model restricted to total terms. Hence, partial order convergence constitutes a conservative extension of metric convergence, which additionally offers a fine-grained distinction between different levels of divergence. In the second part, we focus our investigation on strong convergence...... of orthogonal systems. The main result is that the gap between the metric model and the partial order model can be bridged by extending the term rewriting system by additional rules. These extensions are the well-known Böhm extensions. Based on this result, we are able to establish that -- contrary...

  9. Tetramethylammonium hydrogen terephthalate

    Directory of Open Access Journals (Sweden)

    Leila Dolatyari

    2012-10-01

    Full Text Available The asymmetric unit of the title salt, C4H12N+·C8H5O4−, contains one half of a tetramethylammonium cation and one half of a hydrogen terephthalate monoanion. The N atom of the ammonium cation lies on a twofold rotation axis and the centre of mass of the terephthalate anion is on a centre of inversion. In the crystal, the centrosymmetric terephthalate ions are linked by a very short symmetric O—H...O hydrogen bond [O...O = 2.4610 (19 Å] into a one-dimensional polymeric chain along [1-12]. The tetramethylammonium cations and terephthalate anions are then connected through a pair of bifurcated acceptor C—H...O hydrogen bonds, generating a three-dimensional supramolecular network. The carboxylate groups at both ends of the terephthalate anion are charge-shared with an equal probability of 0.5.

  10. Hydrogen gas detector card

    Directory of Open Access Journals (Sweden)

    Francisco Sánchez Niño

    2016-04-01

    Full Text Available A small card used for detecting hydrogen gas in a crystal growth system by the liquid phase epitaxy technique was designed and built. The small size of the card enables its portability to other laboratories where leakage detection of hydrogen or other flammable gas is required. Card dimensions are approximately 10 cm long and 5 cm wide enabling easy transportation. The design is based on a microcontroller which reads the signal from the hydrogen sensor and internally compares the read value with preset values. Depending on the signal voltage a red, yellow or green LED will light to indicate the levels of concentration of the flammable gas. The card is powered by a 9 V battery.

  11. Magnesium for Hydrogen Storage

    DEFF Research Database (Denmark)

    Pedersen, Allan Schrøder; Kjøller, John; Larsen, B.

    1983-01-01

    A study of the hydrogenation characteristics of fine magnesium powder during repeated cycling has been performed using a high-pressure microbalance facility. No effect was found from the cycling regarding kinetics and storage capacity. The reaction rate of the absorption process was fast at tempe......A study of the hydrogenation characteristics of fine magnesium powder during repeated cycling has been performed using a high-pressure microbalance facility. No effect was found from the cycling regarding kinetics and storage capacity. The reaction rate of the absorption process was fast...... at temperatures around 600 K and above, but the reversed reaction showed somewhat slower kinetics around 600 K. At higher temperatures the opposite was found. The enthalpy and entropy change by the hydrogenation, derived from pressure-concentration isotherms, agree fairly well with those reported earlier....

  12. Hydrogen vehicle fueling station

    Energy Technology Data Exchange (ETDEWEB)

    Daney, D.E.; Edeskuty, F.J.; Daugherty, M.A. [Los Alamos National Lab., NM (United States)] [and others

    1995-09-01

    Hydrogen fueling stations are an essential element in the practical application of hydrogen as a vehicle fuel, and a number of issues such as safety, efficiency, design, and operating procedures can only be accurately addressed by a practical demonstration. Regardless of whether the vehicle is powered by an internal combustion engine or fuel cell, or whether the vehicle has a liquid or gaseous fuel tank, the fueling station is a critical technology which is the link between the local storage facility and the vehicle. Because most merchant hydrogen delivered in the US today (and in the near future) is in liquid form due to the overall economics of production and delivery, we believe a practical refueling station should be designed to receive liquid. Systems studies confirm this assumption for stations fueling up to about 300 vehicles. Our fueling station, aimed at refueling fleet vehicles, will receive hydrogen as a liquid and dispense it as either liquid, high pressure gas, or low pressure gas. Thus, it can refuel any of the three types of tanks proposed for hydrogen-powered vehicles -- liquid, gaseous, or hydride. The paper discusses the fueling station design. Results of a numerical model of liquid hydrogen vehicle tank filling, with emphasis on no vent filling, are presented to illustrate the usefulness of the model as a design tool. Results of our vehicle performance model illustrate our thesis that it is too early to judge what the preferred method of on-board vehicle fuel storage will be in practice -- thus our decision to accommodate all three methods.

  13. Hydrogen: Fueling the Future

    Energy Technology Data Exchange (ETDEWEB)

    Leisch, Jennifer

    2007-02-27

    As our dependence on foreign oil increases and concerns about global climate change rise, the need to develop sustainable energy technologies is becoming increasingly significant. Worldwide energy consumption is expected to double by the year 2050, as will carbon emissions along with it. This increase in emissions is a product of an ever-increasing demand for energy, and a corresponding rise in the combustion of carbon containing fossil fuels such as coal, petroleum, and natural gas. Undisputable scientific evidence indicates significant changes in the global climate have occurred in recent years. Impacts of climate change and the resulting atmospheric warming are extensive, and know no political or geographic boundaries. These far-reaching effects will be manifested as environmental, economic, socioeconomic, and geopolitical issues. Offsetting the projected increase in fossil energy use with renewable energy production will require large increases in renewable energy systems, as well as the ability to store and transport clean domestic fuels. Storage and transport of electricity generated from intermittent resources such as wind and solar is central to the widespread use of renewable energy technologies. Hydrogen created from water electrolysis is an option for energy storage and transport, and represents a pollution-free source of fuel when generated using renewable electricity. The conversion of chemical to electrical energy using fuel cells provides a high efficiency, carbon-free power source. Hydrogen serves to blur the line between stationary and mobile power applications, as it can be used as both a transportation fuel and for stationary electricity generation, with the possibility of a distributed generation energy infrastructure. Hydrogen and fuel cell technologies will be presented as possible pollution-free solutions to present and future energy concerns. Recent hydrogen-related research at SLAC in hydrogen production, fuel cell catalysis, and hydrogen

  14. Hydrogen production from microbial strains

    Science.gov (United States)

    Harwood, Caroline S; Rey, Federico E

    2012-09-18

    The present invention is directed to a method of screening microbe strains capable of generating hydrogen. This method involves inoculating one or more microbes in a sample containing cell culture medium to form an inoculated culture medium. The inoculated culture medium is then incubated under hydrogen producing conditions. Once incubating causes the inoculated culture medium to produce hydrogen, microbes in the culture medium are identified as candidate microbe strains capable of generating hydrogen. Methods of producing hydrogen using one or more of the microbial strains identified as well as the hydrogen producing strains themselves are also disclosed.

  15. Polyhydride complexes for hydrogen storage

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, C.M. [Univ. of Hawaii, Honolulu, HI (United States)

    1995-09-01

    Polyhydride metal complexes are being developed for application in hydrogen storage. Efforts have focused on developing complexes with improved available hydrogen weight percentages. We have explored the possibility that complexes containing aromatic hydrocarbon ligands could store hydrogen at both the metal center and in the ligands. We have synthesized novel indenyl hydride complexes and explored their reactivity with hydrogen. The reversible hydrogenation of [IrH{sub 3}(PPh{sub 3})({eta}{sup 5}-C{sub 10}H{sub 7})]{sup +} has been achieved. While attempting to prepare {eta}{sup 6}-tetrahydronaphthalene complexes, we discovered that certain polyhydride complexes catalyze both the hydrogenation and dehydrogenation of tetrahydronaphthalene.

  16. Electrocatalysts for hydrogen energy

    CERN Document Server

    Losiewicz, Bozena

    2015-01-01

    This special topic volume deals with the development of novel solid state electrocatalysts of a high performance to enhance the rates of the hydrogen or oxygen evolution. It contains a description of various types of metals, alloys and composites which have been obtained using electrodeposition in aqueous solutions that has been identified to be a technologically feasible and economically superior technique for the production of the porous electrodes. The goal was to produce papers that would be useful to both the novice and the expert in hydrogen technologies. This volume is intended to be us

  17. Hydrogen bonded supramolecular materials

    CERN Document Server

    Li, Zhan-Ting

    2015-01-01

    This book is an up-to-date text covering topics in utilizing hydrogen bonding for constructing functional architectures and supramolecular materials. The first chapter addresses the control of photo-induced electron and energy transfer. The second chapter summarizes the formation of nano-porous materials. The following two chapters introduce self-assembled gels, many of which exhibit unique functions. Other chapters cover the advances in supramolecular liquid crystals and the versatility of hydrogen bonding in tuning/improving the properties and performance of materials. This book is designed

  18. Electrochemical Hydrogen Evolution

    DEFF Research Database (Denmark)

    Laursen, A.B.; Varela Gasque, Ana Sofia; Dionigi, F.

    2012-01-01

    The electrochemical hydrogen evolution reaction (HER) is growing in significance as society begins to rely more on renewable energy sources such as wind and solar power. Thus, research on designing new, inexpensive, and abundant HER catalysts is important. Here, we describe how a simple experiment....... The curve visually shows students that the best HER catalysts are characterized by an optimal hydrogen binding energy (reactivity), as stated by the Sabatier principle. In addition, students may use this volcano curve to predict the activity of an untested catalyst solely from the catalyst reactivity...

  19. Hydrogen Energy Conversion

    Science.gov (United States)

    1976-07-27

    Schoeppei, R.J. and Gray, C.L., "The Hydrogen Engine in P^srectl^e", Proceedings 7th international Energy Conversion Encrineering C^ference.: San Dxego...Conversion Engineering Conference, San Diego, Sept. 19/^, pp. 1349-1354. 10. Hausz, W., Leeth, G., and Meyer, C., "Eco-Energy", ibid, pp. 1316-1322. II...75114, . 24. ^schütz, R.H., "Hydrogen Burning Engine Experience", presented at Symposium, see Ref. 8. 25. A. Presto filipo (Pnblio Service’Electric S

  20. Partial domain wall partition functions

    National Research Council Canada - National Science Library

    Foda, O; Wheeler, M

    2012-01-01

    We consider six-vertex model configurations on an (n × N) lattice, n ≤ N, that satisfy a variation on domain wall boundary conditions that we define and call partial domain wall boundary conditions...

  1. Physics of partially ionized plasmas

    CERN Document Server

    Krishan, Vinod

    2016-01-01

    Plasma is one of the four fundamental states of matter; the other three being solid, liquid and gas. Several components, such as molecular clouds, diffuse interstellar gas, the solar atmosphere, the Earth's ionosphere and laboratory plasmas, including fusion plasmas, constitute the partially ionized plasmas. This book discusses different aspects of partially ionized plasmas including multi-fluid description, equilibrium and types of waves. The discussion goes on to cover the reionization phase of the universe, along with a brief description of high discharge plasmas, tokomak plasmas and laser plasmas. Various elastic and inelastic collisions amongst the three particle species are also presented. In addition, the author demonstrates the novelty of partially ionized plasmas using many examples; for instance, in partially ionized plasma the magnetic induction is subjected to the ambipolar diffusion and the Hall effect, as well as the usual resistive dissipation. Also included is an observation of kinematic dynam...

  2. Autópsia psicológica e psicossocial sobre suicídio de idosos: abordagem metodológica Psychological and psychosocial autopsy on suicide among the elderly: a methodological approach

    Directory of Open Access Journals (Sweden)

    Fátima Gonçalves Cavalcante

    2012-08-01

    Full Text Available O artigo analisa a qualidade e a consistência de um roteiro de entrevista semiestruturada, adaptado para o estudo do suicídio de pessoas idosas e apresenta o método das autópsias psicossociais que resultou da aplicação desse instrumento. O objetivo é demonstrar como o uso da entrevista em profundidade e sua forma de organização e análise de dados foram testados e aperfeiçoados por uma rede de pesquisadores de vários centros de pesquisa do Brasil. O método envolveu a aplicação do instrumento em que se socializou um manual de instruções sobre a coleta, sistematização e análise de dados. A metodologia foi aplicada no estudo de 51 casos de idosos que faleceram por suicídio em dez municípios brasileiros, e permitiu a verificação da consistência do instrumento usado e a aplicabilidade do seu método, durante o processo e ao final, por meio de uma avaliação em rede. O roteiro aperfeiçoado e as instruções para replicá-lo e analisá-lo são aqui apresentados. Os resultados apontam o rigor e a credibilidade dessa abordagem metodológica testada e qualificada de um modo interdisciplinar e interinstitucional.The article analyzes the quality and consistency of a semi-structured interview script, adapted for the study on suicide among elderly people, and presents the psychological and psychosocial autopsy method, which is the result of application of this instrument. The objective is to demonstrate how the in-depth interview and subsequent data organization and analyses were tested and improved by a network of researchers from eight regions in Brazil. Evaluation of the method was conducted before and after the application of the instruments to collect, systematize and analyze the data. This methodology was applied in 51 cases of elderly people who committed suicide in ten Brazilian municipalities. The study did more than just collect data with scientific rigor, since it also verified the consistency of the instrument used and

  3. Neurocisticercose: estudo clínico e patológico de 27 casos de necrópsia Neurocysticercosis: a clinical and pathological study of 27 necropsied cases

    Directory of Open Access Journals (Sweden)

    MÁRIO RODRIGUES MONTEMÓR NETTO

    2000-09-01

    Full Text Available Neurocisticercose é a mais frequente e disseminada neuroparasitose humana. O desenvolvimento de lesões no cérebro e leptomeninges, com consequente aparecimento de sintomas, está relacionado com a resposta imune do hospedeiro, ao número e à fase de involução dos parasitas . Relatamos os achados anatomopatológicos durante a necrópsia em 27 casos de neurocisticercose, que corresponderam a 3,1% dos casos necropsiados no serviço. 77% dos pacientes eram masculinos, com idade variando entre 18 e 85 anos. Em 26% dos casos havia história de alcoolismo. A análise clinico-patológica mostrou que 50% dos casos eram da forma assintomática, 11% da forma epiléptica, 11% da forma intraventricular e 11% da forma combinada. 33% dos pacientes apresentaram crise epiléptica como fator agravante do quadro clínico. O cisticerco era único em 60% dos casos, a forma cellulosae estava presente em 82% e a racemosa em 7% dos casos, sendo os 11% restantes portadores da forma combinada. Em 30% dos pacientes a causa mortis estava relacionada com a presença do cisticerco no sistema nervoso central. Nossos achados confirmam a alta morbidade desta parasitose.Neurocysticercosis is the most frequent and widespread neuroparasitosis of the human being. The development of brain and leptomeningeal lesions, with subsequent symptoms, are mainly related with the immune status of the host, and to the number and evolutional phase of the parasites. We present the pathological findings in 27 necropsies of patients with neurocysticercosis, which accounted for 3.1% of the necropsies. 77% of the patients were male and the age ranged from 18 to 85 years. In 26% there was previous history of alcoholism. Clinicopathological study showed that 50% of the cases were classified as asymptomatic form, 11% epileptic form, 11% intraventricular form and 11% combined form. 33% of the patients presented seizures as a factor of aggravation of the clinical picture. There was a single

  4. Introduction to partial differential equations

    CERN Document Server

    Greenspan, Donald

    2000-01-01

    Designed for use in a one-semester course by seniors and beginning graduate students, this rigorous presentation explores practical methods of solving differential equations, plus the unifying theory underlying the mathematical superstructure. Topics include basic concepts, Fourier series, second-order partial differential equations, wave equation, potential equation, heat equation, approximate solution of partial differential equations, and more. Exercises appear at the ends of most chapters. 1961 edition.

  5. NASA Lewis advanced individual pressure vessel (IPV) nickel/hydrogen technology

    Science.gov (United States)

    Smithrick, John J.; Britton, Doris L.

    Individual pressure vessel (IPV) nickel/hydrogen technology was advanced at NASA Lewis and under Lewis contracts. Some of the advancements are as follows: (1) to use 26% KOH electrolyte to improve cycle life and performance; (ii) to modify the state-of-the-art cell design to eliminate identified failure modes and further improve cycle life, and (iii) to develop a lightweight nickel electrode to reduce battery mass, hence reduce launch and/ or increase satellite payload. A breakthrough in the Low-Earth-Orbit (LEO) cycle life of individual pressure vessel nickel/hydrogen battery cells was reported. The cycle life of boiler plate cells containing 26% KOH electrolyte was about 40 000 accelerated LEO cycles at 80% depth-of-discharge (DOD) compared with 3500 cycles for cells containing 31% KOH. Results of the boiler plate cells tests have been validated at Naval Weapons Support Center, Crane, IN. Forty-eight Ah flight cells containing 26 and 31% KOH have undergone real time LEO cycle life testing at an 80% DOD, in 10 °C. The three cells containing 26% KOH failed on the average at cycle 19 500. The three cells containing 31% KOH failed on the average at cycle 6400. Validation testing of NASA Lewis 125 Ah advanced design IPV nickel/hydrogen flight cells is also being conducted at Naval Weapons Support Center, Crane, IN under a NASA Lewis contract. This consists of characterization, storage, and cycle-life testing. There was no capacity degradation after 52 days of storage with the cells in the discharged state, on open circuit, 0 °C, and a hydrogen pressure of 14.5 psia (1 atm). The catalyzed wall wick cells have been cycled for over 22 694 cycles with no cell failures in the continuing test. All three of the noncatalyzed wall wick cells failed (cycles 9588, 13 900 and 20 575). Cycle-life test results of the Fibrex nickel electrode has demonstrated the feasibility of an improved nickel electrode giving a higher specific energy nickel/hydrogen cell. A nickel/hydrogen

  6. [Acrylic resin removable partial dentures].

    Science.gov (United States)

    de Baat, C; Witter, D J; Creugers, N H J

    2011-01-01

    An acrylic resin removable partial denture is distinguished from other types of removable partial dentures by an all-acrylic resin base which is, in principle, solely supported by the edentulous regions of the tooth arch and in the maxilla also by the hard palate. When compared to the other types of removable partial dentures, the acrylic resin removable partial denture has 3 favourable aspects: the economic aspect, its aesthetic quality and the ease with which it can be extended and adjusted. Disadvantages are an increased risk of caries developing, gingivitis, periodontal disease, denture stomatitis, alveolar bone reduction, tooth migration, triggering of the gag reflex and damage to the acrylic resin base. Present-day indications are ofa temporary or palliative nature or are motivated by economic factors. Special varieties of the acrylic resin removable partial denture are the spoon denture, the flexible denture fabricated of non-rigid acrylic resin, and the two-piece sectional denture. Furthermore, acrylic resin removable partial dentures can be supplied with clasps or reinforced by fibers or metal wires.

  7. Liquid Organic Hydrogen Carriers (LOHCs): Toward a Hydrogen-free Hydrogen Economy.

    Science.gov (United States)

    Preuster, Patrick; Papp, Christian; Wasserscheid, Peter

    2017-01-17

    The need to drastically reduce CO 2 emissions will lead to the transformation of our current, carbon-based energy system to a more sustainable, renewable-based one. In this process, hydrogen will gain increasing importance as secondary energy vector. Energy storage requirements on the TWh scale (to bridge extended times of low wind and sun harvest) and global logistics of renewable energy equivalents will create additional driving forces toward a future hydrogen economy. However, the nature of hydrogen requires dedicated infrastructures, and this has prevented so far the introduction of elemental hydrogen into the energy sector to a large extent. Recent scientific and technological progress in handling hydrogen in chemically bound form as liquid organic hydrogen carrier (LOHC) supports the technological vision that a future hydrogen economy may work without handling large amounts of elemental hydrogen. LOHC systems are composed of pairs of hydrogen-lean and hydrogen-rich organic compounds that store hydrogen by repeated catalytic hydrogenation and dehydrogenation cycles. While hydrogen handling in the form of LOHCs allows for using the existing infrastructure for fuels, it also builds on the existing public confidence in dealing with liquid energy carriers. In contrast to hydrogen storage by hydrogenation of gases, such as CO 2 or N 2 , hydrogen release from LOHC systems produces pure hydrogen after condensation of the high-boiling carrier compounds. This Account highlights the current state-of-the-art in hydrogen storage using LOHC systems. It first introduces fundamental aspects of a future hydrogen economy and derives therefrom requirements for suitable LOHC compounds. Molecular structures that have been successfully applied in the literature are presented, and their property profiles are discussed. Fundamental and applied aspects of the involved hydrogenation and dehydrogenation catalysis are discussed, characteristic differences for the catalytic conversion of

  8. Detection of a transient intramolecular hydrogen bond using (1)JNH scalar couplings.

    Science.gov (United States)

    Xiang, ShengQi; Zweckstetter, Markus

    2014-06-01

    Hydrogen bonds are essential for the structure, stability and folding of proteins. The identification of intramolecular hydrogen bonds, however, is challenging, in particular in transiently folded states. Here we studied the presence of intramolecular hydrogen bonds in the folding nucleus of the coiled-coil structure of the GCN4 leucine zipper. Using one-bond (1)JNH spin-spin coupling constants and hydrogen/deuterium exchange, we demonstrate that a transient intramolecular hydrogen bond is present in the partially helical folding nucleus of GCN(16-31). The data demonstrate that (1)JNH couplings are a sensitive tool for the detection of transient intramolecular hydrogen bonds in challenging systems where the effective/useable protein concentration is low. This includes peptides at natural abundance but also uniformly labeled biomolecules that are limited to low concentrations because of precipitation or aggregation. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. A novel hydrogen oxidizer amidst the sulfur-oxidizing Thiomicrospira lineage

    Science.gov (United States)

    Hansen, Moritz; Perner, Mirjam

    2015-01-01

    Thiomicrospira species are ubiquitously found in various marine environments and appear particularly common in hydrothermal vent systems. Members of this lineage are commonly classified as sulfur-oxidizing chemolithoautotrophs. Although sequencing of Thiomicrospira crunogena's genome has revealed genes that encode enzymes for hydrogen uptake activity and for hydrogenase maturation and assembly, hydrogen uptake ability has so far not been reported for any Thiomicrospira species. We isolated a Thiomicrospira species (SP-41) from a deep sea hydrothermal vent and demonstrated that it can oxidize hydrogen. We show in vivo hydrogen consumption, hydrogen uptake activity in partially purified protein extracts and transcript abundance of hydrogenases during different growth stages. The ability of this strain to oxidize hydrogen opens up new perspectives with respect to the physiology of Thiomicrospira species that have been detected in hydrothermal vents and that have so far been exclusively associated with sulfur oxidation. PMID:25226028

  10. Nanomaterials for Hydrogen Storage

    Indian Academy of Sciences (India)

    temperature T, by an equation analogous to the ideal gas law: π V=iRT. (1). R is the gas .... vehicular applications. Nanomaterials are a ... development of materials for hydrogen storage are the low rate of bulk hydride sorption and the high temperatures required for gas release. 3.0. Bulk material. <100 nm. Nanoparticles.

  11. Nanomaterials for Hydrogen Storage

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 12; Issue 5. Nanomaterials for Hydrogen Storage - The van't Hoff Connection. C S Sunandana. General Article Volume 12 Issue 5 May 2007 pp 31-36. Fulltext. Click here to view fulltext PDF. Permanent link:

  12. A Simple Hydrogen Electrode

    Science.gov (United States)

    Eggen, Per-Odd

    2009-01-01

    This article describes the construction of an inexpensive, robust, and simple hydrogen electrode, as well as the use of this electrode to measure "standard" potentials. In the experiment described here the students can measure the reduction potentials of metal-metal ion pairs directly, without using a secondary reference electrode. Measurements…

  13. Hydrogen storage for automobiles

    Energy Technology Data Exchange (ETDEWEB)

    Strickland, G.

    1979-01-01

    Results of an analysis of hydrogen-fueled automobiles are presented as a part of a continuing study conducted by Lawrence Livermore Laboratory (LLL) on Energy Storage Systems for Automobile Propulsion. The hydrogen is stored either as a metal hydride at moderate pressure in TiFe/sub 0/ /sub 9/Mn/sub 0/ /sub 1/H/sub x/ and at low pressure in MgH/sub x/ catalyzed with 10 wt % Ni, or it is stored in hollow glass microspheres at pressures up to about 400 atm. Improved projections are given for the two hydrides, which are used in combination to take advantage of their complementary properties. In the dual-hydride case and in the microsphere case where Ti-based hydride is used for initial operation, hydrogen is consumed in an internal-combustion engine; whereas in the third case, hydrogen from Ti-based hydride is used with air in an alkaline fuel cell/Ni-Zn battery combination which powers an electric vehicle. Each system is briefly described; and the results of the vehicle analysis are compared with those for the conventional automobile and with electric vehicles powered by Pb-acid or Ni-Zn batteries. Comparisons are made on the basis of automobile weight, initial user cost, and life-cycle cost. In this report, the results are limited to those for the 5-passenger vehicle in the period 1985-1990, and are provided as probable and optimistic values.

  14. Economic data on hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    1943-07-22

    General information is recorded about hydrogenation plants and their operation up to July 1943. For 12 German plants, there is a table indicating date of beginning construction, start of operation, and production capacity, including gas. Another chart gives the same data for foreign plants, in the United States, England, Italy, Iran and Holland. Domestic and foreign partners and agreements are also listed, as well as license returns from hydrogenation. Extent of I.G. Farben patent ownership is given in a short list. Development of production costs for liquid products is indicated for the years 1927-1941. Data on test costs are also given. Production figures for hydrogenation are shown, as well as the share of Farben synthetics in total German fuel production. The report gives a breakdown for requirements of raw materials, manpower, capital, and construction steels for production of four million metric tons of fuels from hydrogenation. Finally, the report lists the special areas in which Farben was carrying on work related to synthetic fuels. The data are given mostly in tabular form.

  15. Hydrogen Storage Technical Team Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-06-01

    The mission of the Hydrogen Storage Technical Team is to accelerate research and innovation that will lead to commercially viable hydrogen-storage technologies that meet the U.S. DRIVE Partnership goals.

  16. Biomimetic Production of Hydrogen

    Science.gov (United States)

    Gust, Devens

    2004-03-01

    The basic reaction for hydrogen generation is formation of molecular hydrogen from two electrons and two protons. Although there are many possible sources for the protons and electrons, and a variety of mechanisms for providing the requisite energy for hydrogen synthesis, the most abundant and readily available source of protons and electrons is water, and the most attractive source of energy for powering the process is sunlight. Not surprisingly, living systems have evolved to take advantage of these sources for materials and energy. Thus, biology provides paradigms for carrying out the reactions necessary for hydrogen production. Photosynthesis in green plants uses sunlight as the source of energy for the oxidation of water to give molecular oxygen, protons, and reduction potential. Some photosynthetic organisms are capable of using this reduction potential, in the form of the reduced redox protein ferredoxin, to reduce protons and produce molecular hydrogen via the action of an hydrogenase enzyme. A variety of other organisms metabolize the reduced carbon compounds that are ultimately the major products of photosynthesis to produce molecular hydrogen. These facts suggest that it might be possible to use light energy to make molecular hydrogen via biomimetic constructs that employ principles similar to those used by natural organisms, or perhaps with hybrid "bionic" systems that combine biomimetic materials with natural enzymes. It is now possible to construct artificial photosynthetic systems that mimic some of the major steps in the natural process.(1) Artificial antennas based on porphyrins, carotenoids and other chromophores absorb light at various wavelengths in the solar spectrum and transfer the harvested excitation energy to artificial photosynthetic reaction centers.(2) In these centers, photoinduced electron transfer uses the energy from light to move an electron from a donor to an acceptor moiety, generating a high-energy charge-separated state

  17. Detroit Commuter Hydrogen Project

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Jerry; Prebo, Brendan

    2010-07-31

    This project was undertaken to demonstrate the viability of using hydrogen as a fuel in an internal combustion engine vehicle for use as a part of a mass transit system. The advantages of hydrogen as a fuel include renew-ability, minimal environmental impact on air quality and the environment, and potential to reduce dependence on foreign energy sources for the transportation sector. Recognizing the potential for the hydrogen fuel concept, the Southeast Michigan Congress of Governments (SEMCOG) determined to consider it in the study of a proposed regional mass transit rail system for southeast Michigan. SEMCOG wanted to evaluate the feasibility of using hydrogen fueled internal combustion engine (H2ICE) vehicles in shuttle buses to connect the Detroit Metro Airport to a proposed, nearby rail station. Shuttle buses are in current use on the airport for passenger parking and inter-terminal transport. This duty cycle is well suited to the application of hydrogen fuel at this time because of the ability to re-fuel vehicles at a single nearby facility, overcoming the challenge of restricted fuel availability in the undeveloped hydrogen fuel infrastructure. A cooperative agreement between SEMCOG and the DOE was initiated and two H2ICE buses were placed in regular passenger service on March 29, 2009 and operated for six months in regular passenger service. The buses were developed and built by the Ford Motor Company. Wayne County Airport Authority provided the location for the demonstration with the airport transportation contractor, Metro Cars Inc. operating the buses. The buses were built on Ford E450 chassis and incorporated a modified a 6.8L V-10 engine with specially designed supercharger, fuel rails and injectors among other sophisticated control systems. Up to 30 kg of on-board gaseous hydrogen were stored in a modular six tank, 350 bar (5000 psi) system to provide a 150 mile driving range. The bus chassis and body were configured to carry nine passengers with

  18. Releasing H2 molecules with a partial pressure difference without the use of temperature

    Science.gov (United States)

    Lee, Hoonkyung; Huang, Bing; Duan, Wenhui; Ihm, Jisoon

    2010-08-01

    Using the pseudopotential density-functional method as well as equilibrium thermodynamic functions, we explore the process of releasing H2 molecules adsorbed on a transition-metal atom caused by the hydrogen-ammonia partial pressure difference. The H2 molecules bind to a transition-metal atom at H2 pressure- NH3 pressure-temperature 50atm-10-9atm-25°C , and they are released at 3atm-10-6atm-25°C . This process involves the same mechanism responsible for carbon monoxide poisoning of hemoglobin with the O2-CO partial pressure difference. We show that our findings can be applicable to an approach to induce hydrogen desorption on nanostructured hydrogen-storage materials without the need for increasing temperature.

  19. Reclassificação do carcinoma broncopulmonar: Diferenciação do tipo histológico em biópsias por imuno-histoquímica

    Directory of Open Access Journals (Sweden)

    Lina Carvalho

    2009-11-01

    Full Text Available Resumo: Os conhecimentos actuais da patologia molecular do cancro do pulmão requerem outra caracterização histológica, para além de carcinoma de células pequenas e carcinoma não pequenas células para suporte da terapia personalizada e entendimento do valor real dos fármacos actualmente disponíveis.Como o diagnóstico e seguimento clínico da maioria dos casos de cancro do pulmão se baseia em produtos de biópsia e citologia, a classificação imunoistoquímica do carcinoma broncopulmonar (IBPCC é necessária para suporte morfológico da classificação da WHO 1999/2004, clarificando as características celulares das neoplasias e o entendimento da carcinogénese.O painel imunoistoquímico reforça os tipos histológicos principais do carcinoma bronco – pulmonar: carcinoma epidermóide (queratinas de alto peso molecular – HWMC, carcinoma adenoscamoso (CK/ /TTF1, MWMC, carcinoma neuroendócrino (Chrg, Syn, CD56, TTF1, Ki67 e adenocarcinoma (CK7, Ck20, TTF1; as variantes do carcinoma de células grandes e do carcinoma sarcomatóide são englobados num único grupo de carcinomas pleomórficos (CK7, TTF1, HWMC, VMT, desmina, actina, onde cabe o polimorfismo e o pleomorfismo celular.A quimioterapia do carcinoma broncopulmonar continuará baseada no platino e na gemcitabina no futuro próximo e a IBPCC será uma ferramenta simples e eficiente para o registo das características e tipos histológicos do carcinoma do pulmão presentes nas biópsias e amostras citológicas para suporte da evidência clínica e dos ensaios farmacêuticos.Rev Port Pneumol 2009; XV (6: 1101-1119 Abstract: The current state of molecular knowledge on lung cancer demands a histological classification which goes beyond small-cell and non-small-cell carcinoma to provide support for tailored therapy in aiding in understanding of the drugs currently available.As diagnosis

  20. Neurocisticercose: contribuição da necrópsia na consolidação da notificação compulsória em Ribeirão Preto-SP, Brazil Neurocysticercosis: contribution of autopsies to consolidation of the compulsory notification in Ribeirão Preto-SP, Brazil

    Directory of Open Access Journals (Sweden)

    LEILA CHIMELLI

    1998-09-01

    Full Text Available O presente estudo tem como objetivo a apresentação dos achados de cisticercose nas necrópsias realizadas no Serviço de Patologia do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto-USP, no período de 1992 a 1997. Das 2522 necrópsias, a neurocisticercose foi detectada em 38 (1,5% dos casos. Destes, 22 (57,9% foram diagnosticados apenas na necrópsia enquanto 16 (42,1% apresentavam exames complementares consistentes com cisticercose. A análise dos prontuários médicos evidenciou que 21 (55,2% eram neurologicamente assintomáticos e a frequência das diversas manifestações clínicas estava de acordo com os dados da literatura. A elevada frequência de indivíduos assintomáticos detectados apenas através da necrópsia demonstra a importância desta como fonte complementar de dados para a consolidação da notificação compulsória da cisticercose. Embasado nos dados do presente estudo, o atual coeficiente de prevalência da cisticercose no município de Ribeirão Preto é 67 casos/100000 habitantes.Neurocysticercosis is a serious public health problem in several countries of Asia, Africa and Latin America. The objective of the present study is to present autopsy findings of neurocysticercosis in the Pathology Division of the University Hospital, Medical School of Ribeirão Preto, University of São Paulo, from 1992 to 1997. Neurocysticercosis was detected in 38 (1.5% of 2522 autopsies. In twenty two (57.9% of these, the diagnosis was made post-mortem, while 16 (42.1% had a previous diagnosis of cysticercosis based on laboratory and imaging studies. Reviewing the medical records, we found that 21 patients (55.2% were neurologically asymptomatic, while the various clinical manifestations in the others were in accordance with the literature. The high frequency of asymptomatic individuals detected only post-mortem indicates the importance of autopsies as an additional source of data to consolidate the compulsory

  1. Correlação diagnóstica anatomoclínica. Aferição retrospectiva do diagnóstico clínico em necrópsias Correlation between anatomo-clinical diagnosis and retrospective assessment of clinical diagnosis in post mortms

    Directory of Open Access Journals (Sweden)

    Marcos Célio de Almeida

    1989-08-01

    Full Text Available Analisaram-se retrospectivamente 200 necrópsias, correlacionando-se os diagnósticos clínicos e anatomopatológicos. Foram consideradas 20 entidades nosológicas para confronto. Os diagnósticos não formulados em vida, embora observados na necrópsia (falso negativo, e que apresentaram os maiores percentuais em relação aos respectivos totais de achados necroscópicos, foram: pielonefrite aguda (100%, embolia pulmonar (87,50%, aneurisma dissecante da aorta (66,66% e broncopneumonia (58,16%. Os diagnósticos formulados em vida que não tiveram confirmação pela necrópsia (falso positivo, e que apresentaram os maiores percentuais em relação aos respectivos totais dos diagnósticos clínicos, foram: tuberculose (69,50%, paracoccidioidomicose (57,14%, septicemia (53,13% e doença de Chagas (44,44%. Houve concordância diagnóstica em 97 (48,50% dos 200 casos. Em 19 (9,50% deles o desacordo diagnóstico, se antes verificado, poderia ter implicado alterações do prognóstico. Enfatiza-se a importância da necrópsia para uma adequada correlação anatomoclínica e discute-se os achados em relação a estudos prévios.The post mortem findings in 200 autopsies were compared with the clinical diagnoses. Twenty diseases were analysed with respect to clinico-pathological correlation. In relation to the respective totals the diseases most frequently missed clinically were (false negative pyelonephrites (100%, pulmonary embolus (87.50% and bronchopneumonia (58.16%. In relation to the respective totals the clinical diagnoses less frequently confirmed (false positive were tuberculosis (69.56%, paracoccidioidomycosis (57.14%, sepsis (53.13% and Chagas'disease (44.44%. There was clinico-pathological agreement in 97 autopsies (48.50%. In 19 cases (9.50% if the diagnostic error had been detected during life this probably would have changes the prognosis. The findings are discussed in the light of previous studies. The importance of routine post

  2. Distrofina na diferenciação das distrofias de duchenne e becker estudo imuno-histoquímico comparado com o estádio clínico, enzimas séricas e biópsia muscular

    OpenAIRE

    Werneck, Lineu Cesar; Bonilla, Eduardo

    1990-01-01

    Foram estudados 55 casos de distrofia muscular progressiva (34 Duchenne, 12 Duchenne com distrofina residual e 9 Becker), comparando idade, época de início e tempo de sintomas, graduação na escala de Vignos e Archibald, níveis de enzimas séricas e presença de distrofina nas biópsias musculares por imunofluorescência. A intensidade dos sintomas, gravidade do quadro clínico, proliferação de tecido ccnjuntivo endomisial e infiltração por tecido adiposo estão inversamente relacionadas à quantidad...

  3. Photovoltaic hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Hiser, H.W.; Memory, S.B.; Veziroglu, T.N.; Padin, J. [Univ. of Miami, Coral Gables, FL (United States)

    1996-10-01

    This is a new project, which started in June 1995, and involves photovoltaic hydrogen production as a fuel production method for the future. In order to increase the hydrogen yield, it was decided to use hybrid solar collectors to generate D.C. electricity, as well as high temperature steam for input to the electrolyzer. In this way, some of the energy needed to dissociate the water is supplied in the form of heat (or low grade energy), to generate steam, which results in a reduction of electrical energy (or high grade energy) needed. As a result, solar to hydrogen conversion efficiency is increased. In the above stated system, the collector location, the collector tracking sub-system (i.e., orientation/rotation), and the steam temperature have been taken as variables. Five locations selected - in order to consider a variety of latitudes, altitudes, cloud coverage and atmospheric conditions - are Atlanta, Denver, Miami, Phoenix and Salt Lake City. Plain PV and hybrid solar collectors for a stationary south facing system and five different collector rotation systems have been analyzed. Steam temperatures have been varied between 200{degrees}C and 1200{degrees}C. During the first year, solar to hydrogen conversion efficiencies have been considered. The results show that higher steam temperatures, 2 dimensional tracking system, higher elevations and dryer climates causes higher conversion efficiencies. Cost effectiveness of the sub-systems and of the overall system will be analyzed during the second year. Also, initial studies will be made of an advanced high efficiency hybrid solar hydrogen production system.

  4. Task D: Hydrogen safety analysis

    Energy Technology Data Exchange (ETDEWEB)

    Swain, M.R.; Sievert, B.G. [Univ. of Miami, Coral Gables, FL (United States); Swain, M.N. [Analytical Technologies, Inc., Miami, FL (United States)

    1996-10-01

    This report covers two topics. The first is a review of codes, standards, regulations, recommendations, certifications, and pamphlets which address safety of gaseous fuels. The second is an experimental investigation of hydrogen flame impingement. Four areas of concern in the conversion of natural gas safety publications to hydrogen safety publications are delineated. Two suggested design criteria for hydrogen vehicle fuel systems are proposed. It is concluded from the experimental work that light weight, low cost, firewalls to resist hydrogen flame impingement are feasible.

  5. Hydrogen Fire Spectroscopy Issues Project

    Science.gov (United States)

    Youngquist, Robert C. (Compiler)

    2014-01-01

    The detection of hydrogen fires is important to the aerospace community. The National Aeronautics and Space Administration (NASA) has devoted significant effort to the development, testing, and installation of hydrogen fire detectors based on ultraviolet, near-infrared, mid-infrared, andor far-infrared flame emission bands. Yet, there is no intensity calibrated hydrogen-air flame spectrum over this range in the literature and consequently, it can be difficult to compare the merits of different radiation-based hydrogen fire detectors.

  6. Partial cecal necrosis treated by laparoscopic partial cecal resection.

    Science.gov (United States)

    Perko, Zdravko; Bilan, Kanito; Vilović, Katarina; Druzijanić, Nikica; Kraljević, Damir; Juriicić, Josko; Krnić, Dragan; Srsen, Darko; Pogorelić, Zenon; Tomić, Snjezana

    2006-12-01

    Acute colonic ischemia is the common cause of colitis in elderly population. However, isolated ischemic necrosis of cecum is rare entity, often associated with variety of conditions. Here we present a case of a 73-year old woman with a past history of hypertension presented with clinical symptoms of right lower quadrant abdominal pain and tenderness localized to the right lower quadrant, guarding and rebound tenderness. With diagnosis of acute appendicitis, the patient underwent laparoscopy where the cecal partial necrosis was discovered. Necrotic area of cecum was excised using two endoscopic cutters and laparoscopic appendectomy was performed. Pathologist report showed thrombosis of vessels and necrosis of entire cecal wall. The patient completely recovered without any surgical complications. This is the first case of partial cecum necrosis laparoscopicaly managed and with a partial cecal resection only.

  7. Hydrogen no-vent fill testing in a 1.2 cubic foot (34 liter) tank

    Science.gov (United States)

    Moran, Matthew E.; Nyland, Ted W.; Driscoll, Susan L.

    1991-01-01

    Experimental results of no-vent fill testing with liquid hydrogen in a 1.2 cubic foot (34 liter) stainless steel tank are presented. More than 40 tests were performed with various liquid inlet temperatures, inlet flowrates, initial tank wall temperatures, and liquid injection techniques. Fill levels equal to or exceeding 90 percent by volume were achieved in 40 percent of the tests with the tank pressure limited to a maximum of 30 psia. Three liquid injection techniques were employed; top spray, upward pipe discharge, and bottom diffuser. Effects of each of the varied parameters on the tank pressure history and final fill level are evaluated. The final fill level is found to be indirectly proportional to the initial wall and inlet liquid temperatures and directly proportional to the inlet liquid flowrate. Furthermore, the top spray is the most efficient no-vent fill method of the three configurations examined. The success of this injection method is primarily due to condensation of the ullage vapor onto the incoming liquid droplets. Ullage condensation counteracts the tank pressure rise resulting from energy exchange between the fluid and the warmer tank walls, and ullage compression. Upward pipe discharge from the tank bottom is the next most efficient method. Fluid circulation induced by this fill configuration tends to diminish thermal stratification in the bulk liquid, thus enhancing condensation at the liquid gas interface.

  8. Magnetic levitation of condensed hydrogen

    Science.gov (United States)

    Paine, C. G.; Seidel, G. M.

    1991-01-01

    Liquid and solid molecular hydrogen has been levitated using a pair of small superconducting solenoids. The hydrogen samples, up to 3 mm in dimension, were trapped in a magnetic potential having either a discrete minimum or a minimum in the form of a ring 1 cm in diameter. The hydrogen could be moved about in the magnetic trap by applying an electric field.

  9. HYDROGEN VACANCY INTERACTION IN MOLYBDENUM

    NARCIS (Netherlands)

    Abd El Keriem, M.S.; van der Werf, D.P.; Pleiter, F

    1993-01-01

    Vacancy-hydrogen interaction in molybdenum was investigated by means of the perturbed angular correlation technique, using the isotope In-111 as a probe. The complex InV2 turned out to trap up to two hydrogen atoms: trapping of a single hydrogen atom gives rise to a decrease of the quadrupole

  10. Muonic processes in solid hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, G.M.; Beveridge, J.L. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC (Canada); Bailey, J.M. [Chester Technology, Chester (United Kingdom); Beer, G.A.; Knowles, P.E.; Maier, M.; Mason, G.R.; Olin, A.; Porcelli, T.A. [University of Victoria, Victoria, BC (Canada); Fujiwara, M.C. [University of British Columbia, Vancouver, BC (Canada); Huber, T.M. [Gustavus Adolphus College, St. Peter, Minnesota (United States); Jacot-Guillarmod, R.; Mulhauser, F.; Schaller, L.A. [University of Fribourg, Fribourg (Switzerland); Kammel, P. [Lawrence Berkeley Laboratory, Berkeley, California (United States); Kim, S.K. [Jeonbuk National University, Jeonju City, S. (Korea); Kunselman, A.R. [University of Wyoming, Laramie, Wyoming (United States); Petitjean, C. [PSI, Villigen (Switzerland); Zmeskal, J. [IMEP, Vienna (Austria)

    1998-08-01

    Muonic hydrogen participates in many different interactions, including muon induced fusion of hydrogen nuclei. Conventional experimental techniques cannot always unravel and separate the processes of interest. Some of the most important measurements may be more reliably accomplished with the use of a unique and versatile target consisting of layers of different solid hydrogen isotope mixtures. {copyright} {ital 1998 American Institute of Physics.}

  11. Realizing a hydrogen future: Hydrogen Technical Advisory Panel recommendations (brochure)

    Energy Technology Data Exchange (ETDEWEB)

    Cook, G.

    1999-08-01

    When generated from renewable sources, hydrogen production and use is part of a clean, cyclic process. Hydrogen can be used to generate electricity, heat homes and businesses, fuel vehicles, and produce commodities used every day. The Hydrogen Technical Advisory Panel's (HTAP) primary functions are to advise the Secretary of Energy on the implementation of the U.S.DOE programs in hydrogen RD and D and to review and make recommendations on the economic, technical, and environmental consequences of deploying safe hydrogen energy systems.

  12. Adsorption of hydrogen gas and redox processes in clays.

    Science.gov (United States)

    Didier, Mathilde; Leone, Laura; Greneche, Jean-Marc; Giffaut, Eric; Charlet, Laurent

    2012-03-20

    In order to assess the adsorption properties of hydrogen gas and reactivity of adsorbed hydrogen, we measured H(2)(g) adsorption on Na synthetic montmorillonite-type clays and Callovo-Oxfordian (COx) clayrock using gas chromatography. Synthetic montmorillonites with increasing structural Fe(III) substitution (0 wt %, 3.2 wt %, and 6.4 wt % Fe) were used. Fe in the synthetic montmorillonites is principally present as structural Fe(III) ions. We studied the concomitant reduction of structural Fe(III) in the clays using (57)Fe Mössbauer spectrometry. The COx, which mainly contains smectite/illite and calcite minerals, is also studied together with the pure clay fraction of this clayrock. Experiments were performed with dry clay samples which were reacted with hydrogen gas at 90 and 120 °C for 30 to 45 days at a hydrogen partial pressure close to 0.45 bar. Results indicate that up to 0.11 wt % of hydrogen is adsorbed on the clays at 90 °C under 0.45 bar of relative pressure. (57)Fe Mössbauer spectrometry shows that up to 6% of the total structural Fe(III) initially present in these synthetic clays is reduced upon adsorption of hydrogen gas. No reduction is observed with the COx sample in the present experimental conditions.

  13. Relation between Hydrogen Evolution and Hydrodesulfurization Catalysis

    DEFF Research Database (Denmark)

    Šaric, Manuel; Moses, Poul Georg; Rossmeisl, Jan

    2016-01-01

    A relation between hydrogen evolution and hydrodesulfurization catalysis was found by density functional theory calculations. The hydrogen evolution reaction and the hydrogenation reaction in hydrodesulfurization share hydrogen as a surface intermediate and, thus, have a common elementary step...

  14. Parachute technique for partial penectomy

    Directory of Open Access Journals (Sweden)

    Fernando Korkes

    2010-04-01

    Full Text Available PURPOSE: Penile carcinoma is a rare but mutilating malignancy. In this context, partial penectomy is the most commonly applied approach for best oncological results. We herein propose a simple modification of the classic technique of partial penectomy, for better cosmetic and functional results. TECHNIQUE: If partial penectomy is indicated, the present technique can bring additional benefits. Different from classical technique, the urethra is spatulated only ventrally. An inverted "V" skin flap with 0.5 cm of extension is sectioned ventrally. The suture is performed with vicryl 4-0 in a "parachute" fashion, beginning from the ventral portion of the urethra and the "V" flap, followed by the "V" flap angles and than by the dorsal portion of the penis. After completion of the suture, a Foley catheter and light dressing are placed for 24 hours. CONCLUSIONS: Several complex reconstructive techniques have been previously proposed, but normally require specific surgical abilities, adequate patient selection and staged procedures. We believe that these reconstructive techniques are very useful in some specific subsets of patients. However, the technique herein proposed is a simple alternative that can be applied to all men after a partial penectomy, and takes the same amount of time as that in the classic technique. In conclusion, the "parachute" technique for penile reconstruction after partial amputation not only improves the appearance of the penis, but also maintains an adequate function.

  15. Hydrogen attack - Influence of hydrogen sulfide. [on carbon steel

    Science.gov (United States)

    Eliezer, D.; Nelson, H. G.

    1978-01-01

    An experimental study is conducted on 12.5-mm-thick SAE 1020 steel (plain carbon steel) plate to assess hydrogen attack at room temperature after specimen exposure at 525 C to hydrogen and a blend of hydrogen sulfide and hydrogen at a pressure of 3.5 MN/sq m for exposure times up to 240 hr. The results are discussed in terms of tensile properties, fissure formation, and surface scales. It is shown that hydrogen attack from a high-purity hydrogen environment is severe, with the formation of numerous methane fissures and bubbles along with a significant reduction in the room-temperature tensile yield and ultimate strengths. However, no hydrogen attack is observed in the hydrogen/hydrogen sulfide blend environment, i.e. no fissure or bubble formation occurred and the room-temperature tensile properties remained unchanged. It is suggested that the observed porous discontinuous scale of FeS acts as a barrier to hydrogen entry, thus reducing its effective equilibrium solubility in the iron lattice. Therefore, hydrogen attack should not occur in pressure-vessel steels used in many coal gasification processes.

  16. Electrochemical Hydrogen Peroxide Generator

    Science.gov (United States)

    Tennakoon, Charles L. K.; Singh, Waheguru; Anderson, Kelvin C.

    2010-01-01

    Two-electron reduction of oxygen to produce hydrogen peroxide is a much researched topic. Most of the work has been done in the production of hydrogen peroxide in basic media, in order to address the needs of the pulp and paper industry. However, peroxides under alkaline conditions show poor stabilities and are not useful in disinfection applications. There is a need to design electrocatalysts that are stable and provide good current and energy efficiencies to produce hydrogen peroxide under acidic conditions. The innovation focuses on the in situ generation of hydrogen peroxide using an electrochemical cell having a gas diffusion electrode as the cathode (electrode connected to the negative pole of the power supply) and a platinized titanium anode. The cathode and anode compartments are separated by a readily available cation-exchange membrane (Nafion 117). The anode compartment is fed with deionized water. Generation of oxygen is the anode reaction. Protons from the anode compartment are transferred across the cation-exchange membrane to the cathode compartment by electrostatic attraction towards the negatively charged electrode. The cathode compartment is fed with oxygen. Here, hydrogen peroxide is generated by the reduction of oxygen. Water may also be generated in the cathode. A small amount of water is also transported across the membrane along with hydrated protons transported across the membrane. Generally, each proton is hydrated with 3-5 molecules. The process is unique because hydrogen peroxide is formed as a high-purity aqueous solution. Since there are no hazardous chemicals or liquids used in the process, the disinfection product can be applied directly to water, before entering a water filtration unit to disinfect the incoming water and to prevent the build up of heterotrophic bacteria, for example, in carbon based filters. The competitive advantages of this process are: 1. No consumable chemicals are needed in the process. The only raw materials

  17. Partially massless monopoles and charges

    Science.gov (United States)

    Hinterbichler, Kurt; Rosen, Rachel A.

    2015-11-01

    Massive higher spin fields on de Sitter space exhibit enhanced gauge symmetries at special values of the mass. These fields are known as "partially massless." We study the structure of the charges and Gauss laws which characterize sources for the partially massless spin-2. Despite having a simple scalar gauge symmetry, there is a rich structure of gauge charges. The charges come in electric and magnetic varieties, each taking values in the fundamental representation of the de Sitter group. We find two invariant electriclike charges and two invariant magneticlike charges and we find the pointlike monopole solutions which carry these charges, analogous to the electric point-charge solution and Dirac monopole solution of Maxwell electrodynamics. These solutions are related by partially massless duality, analogous to the electromagnetic duality that relates electric to magnetic charges.

  18. [Partial lipodystrophy: a spot diagnosis].

    Science.gov (United States)

    Fidder, A R Sander; van der Deure, Hans J; Westra, Dineke W

    2015-01-01

    Partial lipodystrophy is a rare acquired disorder characterised by gradual loss of subcutaneous adipose tissue in the upper half of the body. We saw a 9-year-old girl who had been referred on account of recurrent urinary tract infections. On physical examination, she was noticed to be very thin in the face. Her upper extremities were also skinny. Strikingly, the lower half of her body was normally proportioned, which immediately suggested a diagnosis of partial lipodystrophy. Additional examinations showed a low level of complement factor C3 and the presence of C3 nephritic factor. Partial lipodystrophy is rare but it is important to include it in the differential diagnosis of unwanted disproportional subcutaneous fat loss because of the somatic and psychological consequences.

  19. Partially composite Goldstone Higgs boson

    DEFF Research Database (Denmark)

    Alanne, Tommi; Franzosi, Diogo Buarque; Frandsen, Mads T.

    2017-01-01

    We consider a model of dynamical electroweak symmetry breaking with a partially composite Goldstone Higgs boson. The model is based on a strongly interacting fermionic sector coupled to a fundamental scalar sector via Yukawa interactions. The SU(4)×SU(4) global symmetry of these two sectors...... is broken to a single SU(4) via Yukawa interactions. Electroweak symmetry breaking is dynamically induced by condensation due to the strong interactions in the new fermionic sector which further breaks the global symmetry SU(4)→Sp(4). The Higgs boson arises as a partially composite state which is an exact...... Goldstone boson in the limit where SM interactions are turned off. Terms breaking the SU(4) global symmetry explicitly generate a mass for the Goldstone Higgs boson. The model realizes in different limits both (partially) composite Higgs and (bosonic) technicolor models, thereby providing a convenient...

  20. Partial monoids: associativity and confluence

    CERN Document Server

    Poinsot, Laurent; Tollu, Christophe

    2010-01-01

    A partial monoid $P$ is a set with a partial multiplication $\\times$ (and total identity $1_P$) which satisfies some associativity axiom. The partial monoid $P$ may be embedded in a free monoid $P^*$ and the product $\\star$ is simulated by a string rewriting system on $P^*$ that consists in evaluating the concatenation of two letters as a product in $P$, when it is defined, and a letter $1_P$ as the empty word $\\epsilon$. In this paper we study the profound relations between confluence for such a system and associativity of the multiplication. Moreover we develop a reduction strategy to ensure confluence and which allows us to define a multiplication on normal forms associative up to a given congruence of $P^*$. Finally we show that this operation is associative if, and only if, the rewriting system under consideration is confluent.

  1. Partial metrizability in value quantales

    Directory of Open Access Journals (Sweden)

    Ralph D. Kopperman

    2004-04-01

    Full Text Available Partial metrics are metrics except that the distance from a point to itself need not be 0. These are useful in modelling partially defined information, which often appears in computer science. We generalize this notion to study “partial metrics” whose values lie in a value quantale which may be other than the reals. Then each topology arises from such a generalized metric, and for each continuous poset, there is such a generalized metric whose topology is the Scott topology, and whose dual topology is the lower topology. These are both corollaries to our result that a bitopological space is pairwise completely regular if and only if there is such a generalized metric whose topology is the first topology, and whose dual topology is the second.

  2. Causes and Consequences of Partial Migration in a Passerine Bird.

    Science.gov (United States)

    Hegemann, Arne; Marra, Peter P; Tieleman, B Irene

    2015-10-01

    Many animal species have populations in which some individuals migrate and others remain on the breeding grounds. This phenomenon is called partial migration. Despite substantial theoretical work, empirical data on causes and consequences of partial migration remain scarce, mainly because of difficulties associated with tracking individuals over large spatial scales. We used stable hydrogen isotopes in claw material to determine whether skylarks Alauda arvensis from a single breeding population in the Netherlands had migrated or remained resident in the previous winter and investigated whether there were causes or consequences of either strategy. Age and sex had no influence on the propensity to migrate, but larger individuals were more likely to be residents. The wintering strategy was not fixed within individuals. Up to 45% of individuals measured in multiple years switched strategies. Reproductive parameters were not related to the wintering strategy, but individuals that wintered locally experienced lower future return rates, and this was directly correlated with two independent measures of immune function. Our results suggest that partial migration in skylarks is based neither on genetic dimorphism nor on an age- and sex-dependent condition. Instead, the wintering strategy is related to structural size and immune function. These new insights on causes and consequences of partial migration advance our understanding of the ecology, evolution, and coexistence of different life-history strategies.

  3. A case for partial patellectomy.

    Directory of Open Access Journals (Sweden)

    Mittal V

    1995-04-01

    Full Text Available The treatment of fractures of the the patella is a subject of controversy. Partial patellectomy with retention of a major fragment and suture of the quadriceps to it, seems reasonable. 18 cases of patella fracture underwent such a procedure. The average age of the patients was 47 years. Maximum recovery took an average of 5 months. There were 6 excellent results, 9 good, 3 fair. Results were assessed on the basis of pain, muscle wasting, quadriceps power, and range of knee motion. Total patellectomy and patella fixation as alternative modes of treatment are discussed. Partial patellectomy, whenever possible, is a good choice.

  4. Yet another partial wave calculator

    Energy Technology Data Exchange (ETDEWEB)

    Greenwald, Daniel; Rauch, Johannes [TUM, Munich (Germany)

    2016-07-01

    We will present a new C++ library for partial wave analysis: YAP - yet another partial wave calculator. YAP is intended for amplitude analyses of the decays of spin-0 heavy mesons (principally B and D) to multiple (3, 4, etc.) pseudoscalar mesons but is not hard coded for such situations and is flexible enough to handle other decay scenarios. The library allows for both model dependent and model independent analysis methods. We introduce the software, and demonstrate examples for generating Monte Carlo data efficiently, and for analyzing data (both with the aid of the Bayesian Analysis Toolkit).

  5. Basic linear partial differential equations

    CERN Document Server

    Treves, Francois

    1975-01-01

    Focusing on the archetypes of linear partial differential equations, this text for upper-level undergraduates and graduate students features most of the basic classical results. The methods, however, are decidedly nontraditional: in practically every instance, they tend toward a high level of abstraction. This approach recalls classical material to contemporary analysts in a language they can understand, as well as exploiting the field's wealth of examples as an introduction to modern theories.The four-part treatment covers the basic examples of linear partial differential equations and their

  6. Elements of partial differential equations

    CERN Document Server

    Sneddon, Ian N

    2006-01-01

    Geared toward students of applied rather than pure mathematics, this volume introduces elements of partial differential equations. Its focus is primarily upon finding solutions to particular equations rather than general theory.Topics include ordinary differential equations in more than two variables, partial differential equations of the first and second orders, Laplace's equation, the wave equation, and the diffusion equation. A helpful Appendix offers information on systems of surfaces, and solutions to the odd-numbered problems appear at the end of the book. Readers pursuing independent st

  7. Basic linear partial differential equations

    CERN Document Server

    Treves, Francois

    2006-01-01

    Focusing on the archetypes of linear partial differential equations, this text for upper-level undergraduates and graduate students features most of the basic classical results. The methods, however, are decidedly nontraditional: in practically every instance, they tend toward a high level of abstraction. This approach recalls classical material to contemporary analysts in a language they can understand, as well as exploiting the field's wealth of examples as an introduction to modern theories.The four-part treatment covers the basic examples of linear partial differential equations and their

  8. Elements of partial differential equations

    CERN Document Server

    Sneddon, Ian Naismith

    1957-01-01

    Geared toward students of applied rather than pure mathematics, this volume introduces elements of partial differential equations. Its focus is primarily upon finding solutions to particular equations rather than general theory.Topics include ordinary differential equations in more than two variables, partial differential equations of the first and second orders, Laplace's equation, the wave equation, and the diffusion equation. A helpful Appendix offers information on systems of surfaces, and solutions to the odd-numbered problems appear at the end of the book. Readers pursuing independent st

  9. Adaptive Partially Hidden Markov Models

    DEFF Research Database (Denmark)

    Forchhammer, Søren Otto; Rasmussen, Tage

    1996-01-01

    Partially Hidden Markov Models (PHMM) have recently been introduced. The transition and emission probabilities are conditioned on the past. In this report, the PHMM is extended with a multiple token version. The different versions of the PHMM are applied to bi-level image coding.......Partially Hidden Markov Models (PHMM) have recently been introduced. The transition and emission probabilities are conditioned on the past. In this report, the PHMM is extended with a multiple token version. The different versions of the PHMM are applied to bi-level image coding....

  10. Ácidos graxos plasmáticos, metabolismo lipídico e lipoproteínas de ratos alimentados com óleo de palma e óleo de soja parcialmente hidrogenado Plasma fatty acids, lipid metabolism and lipoproteins in rats fed on palm oil and partially hydrogenated soybean oil

    Directory of Open Access Journals (Sweden)

    Ana Paula Silva

    2005-04-01

    Full Text Available OBJETIVO: Comparar, em ratos jovens, os efeitos metabólicos de dietas distintas, à base de óleo de palma e de gordura hidrogenada. MÉTODOS: Ratas Wistar receberam dietas com diferentes fontes lipídicas durante a lactação, as quais continuaram a ser dadas aos filhotes machos do 21º dia ao 45º dia de vida, após ajuste às recomendações da American Institute of Nutrition-93, quando estes foram decapitados. Os tecidos adiposos epididimal e perirrenal foram retirados para determinação da taxa de lipogênese in vivo com ³H2O e, no plasma, avaliou-se o perfil de ácidos graxos por cromatografia gasosa, além da concentração dos triacilgliceróis e colesterol total, por meio de kits enzimáticos. RESULTADOS: A substituição, na dieta, da gordura hidrogenada pelo óleo de palma aumentou, no plasma, a proporção do ácido graxo araquidônico e diminuiu a proporção do ácido essencial linolênico e a concentração dos triacilgliceróis e colesterol. Elevou o conteúdo lipídico e a taxa lipogênica do epidídimo e perirenal, repercutindo em maior peso corporal, bem como na adiposidade nesses animais. CONCLUSÃO: O tipo de ácido graxo oferecido na dieta desde o período da lactação, pode influenciar o metabolismo lipídico do tecido adiposo na idade jovem, bem como o comportamento alimentar e ganho de peso corporal, com possíveis repercussões para o desenvolvimento de doenças crônicas não transmissíveis.OBJECTIVE: To compare the metabolic effects of diets based on palm oil and hydrogenated fat on young rats. METHODS: Wistar female rats, during lactation, were fed diets with different lipid sources, which were also adjusted to the recommendations (American Institute of Nutrition-93 and given to the male pups from the 21rst day to the 45th day of life, when they were killed. The epididimal and perirenal adipose tissues were extracted and had their lipogenesis rates measured in vivo with ³H2O. We also measured, in the plasma

  11. Hydrogen adsorption on rhodium

    Energy Technology Data Exchange (ETDEWEB)

    Belyaeva, M.E.; Michri, A.A.; Kalish, T.V.; Pshenichnikov, A.G.; Kazarinov, V.E.

    1987-09-01

    Measurements of thermal desorption and electron work function were used to investigate the mechanism of hydrogen adsorption from the gas phase on rhodium single-crystal faces and on a polycrystalline rhodium sample at room temperatures over the pressure range from 1.3-10/sup -3/ to 1.3 x 10/sup -5/ Pa. It was found that dipoles oriented with their negative ends toward the gas phase (dipoles of type I) form more rapidly than dipoles having the opposite orientation (dipoles of type II). For formation of the latter, a mechanism is proposed according to which the rate-determining step of the overall process is the transition of reversibly adsorbed hydrogen to dipoles of type II (the spillover), which occurs at surface defects. It was shown that the kinetics of this process with respect to the individual defect obeys an equation which is zeroth order in theta/sub H/ and pressure.

  12. Reversible hydrogen storage materials

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, James A [Lexington, SC; Wang, Tao [Columbia, SC; Ebner, Armin D [Lexington, SC; Holland, Charles E [Cayce, SC

    2012-04-10

    In accordance with the present disclosure, a process for synthesis of a complex hydride material for hydrogen storage is provided. The process includes mixing a borohydride with at least one additive agent and at least one catalyst and heating the mixture at a temperature of less than about 600.degree. C. and a pressure of H.sub.2 gas to form a complex hydride material. The complex hydride material comprises MAl.sub.xB.sub.yH.sub.z, wherein M is an alkali metal or group IIA metal, Al is the element aluminum, x is any number from 0 to 1, B is the element boron, y is a number from 0 to 13, and z is a number from 4 to 57 with the additive agent and catalyst still being present. The complex hydride material is capable of cyclic dehydrogenation and rehydrogenation and has a hydrogen capacity of at least about 4 weight percent.

  13. Offshore Facilities to Produce Hydrogen

    Directory of Open Access Journals (Sweden)

    Pilar Blanco-Fernández

    2017-06-01

    Full Text Available As a result of international agreements on the reduction of CO2 emissions, new technologies using hydrogen are being developed. Hydrogen, despite being the most abundant element in Nature, cannot be found in its pure state. Water is one of the most abundant sources of hydrogen on the planet. The proposal here is to use energy from the sea in order to obtain hydrogen from water. If plants to obtain hydrogen were to be placed in the ocean, the impact of long submarines piping to the coast will be reduced. Further, this will open the way for the development of ships propelled by hydrogen. This paper discusses the feasibility of an offshore installation to obtain hydrogen from the sea, using ocean wave energy.

  14. INVESTIGATIONS ON BIOCHEMICAL PURIFICATION OF GROUND WATER FROM HYDROGEN SULFIDE

    Directory of Open Access Journals (Sweden)

    Yu. P. Sedlukho

    2015-01-01

    Full Text Available The paper considers problems and features of biochemical removal of hydrogen sulfide from ground water. The analysis of existing methods for purification of ground water from hydrogen sulfide has been given in the paper. The paper has established shortcomings of physical and chemical purification of ground water. While using aeration methods for removal of hydrogen sulfide formation of colloidal sulfur that gives muddiness and opalescence to water occurs due to partial chemical air oxidation. In addition to this violation of sulfide-carbonate equilibrium taking place in the process of aeration due to desorption of H2S and CO2, often leads to clogging of degasifier nozzles with formed CaCO3 that causes serious operational problems. Chemical methods require relatively large flow of complex reagent facilities, storage facilities and transportation costs.In terms of hydrogen sulfide ground water purification the greatest interest is given to the biochemical method. Factors deterring widespread application of the biochemical method is its insufficient previous investigation and necessity to execute special research in order to determine optimal process parameters while purifying groundwater of a particular water supply source. Biochemical methods for oxidation of sulfur compounds are based on natural biological processes that ensure natural sulfur cycle. S. Vinogradsky has established a two-stage mechanism for oxidation of hydrogen sulfide with sulfur bacteria (Beggiatoa. The first stage presupposes oxidation of hydrogen sulphide to elemental sulfur which is accumulating in the cytoplasm in the form of globules. During the second stage sulfur bacteria begin to oxidize intracellular sulfur to sulfuric acid due to shortage of hydrogen sulfide.The paper provides the results of technological tests of large-scale pilot plants for biochemical purification of groundwater from hydrogen sulfide in semi-industrial conditions. Dependences of water quality

  15. Positively charged phosphorus as a hydrogen bond acceptor

    DEFF Research Database (Denmark)

    Hansen, Anne Schou; Du, Lin; Kjærgaard, Henrik Grum

    2014-01-01

    Phosphorus (P) is an element that is essential to the life of all organisms, and the atmospheric detection of phosphine suggests the existence of a volatile biogeochemical P cycle. Here, we investigate the ability of P to participate in the formation of OH···P hydrogen bonds. Three bimolecular......-stretching frequency red shifts and quantum chemical calculations, we find that P is an acceptor atom similar in strength to O and S and that all three P, O, and S atoms are weaker acceptors than N. The quantum chemical calculations show that both H and P in the OH···P hydrogen bond have partial positive charges......, as expected from their electronegativities. However, the electrostatic potentials show a negative potential area on the electron density surface around P that facilitates formation of hydrogen bonds....

  16. Hydrogen production from agricultural waste by dark fermentation: A review

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Xin Mei; Trably, Eric; Latrille, Eric; Carrere, Helene; Steyer, Jean-Philippe [INRA, UR050, Laboratoire de Biotechnologie de l' Environnement, F-11100 Narbonne (France)

    2010-10-15

    The degradation of the natural environment and the energy crisis are two vital issues for sustainable development worldwide. Hydrogen is considered as one of the most promising candidates as a substitute for fossil fuels. In this context, biological processes are considered as the most environmentally friendly alternatives for satisfying future hydrogen demands. In particular, biohydrogen production from agricultural waste is very advantageous since agri-wastes are abundant, cheap, renewable and highly biodegradable. Considering that such wastes are complex substrates and can be degraded biologically by complex microbial ecosystems, the present paper focuses on dark fermentation as a key technology for producing hydrogen from crop residues, livestock waste and food waste. In this review, recent findings on biohydrogen production from agricultural wastes by dark fermentation are reported. Key operational parameters such as pH, partial pressure, temperature and microbial actors are discussed to facilitate further research in this domain. (author)

  17. Molecular and Metallic Hydrogen

    Science.gov (United States)

    1977-05-01

    Livermore Laboratory, Dr. J. C. Raich of the Colorado State University, and Dr. R. H. Wentorf, Jr., of the General Electric Company for their reviews...investigated by Raich and Etters [8], who have made ground-state energy calculations for hydrogen molecules retaining the orientation dependence of the...consistent with work of Raich and Etters [8], who have made similar calculations during the course of their work on the rotational transition in solid

  18. Coal liquefaction and hydrogenation

    Science.gov (United States)

    Schindler, Harvey D.

    1985-01-01

    The coal liquefaction process disclosed uses three stages. The first stage is a liquefaction. The second and third stages are hydrogenation stages at different temperatures and in parallel or in series. One stage is within 650.degree.-795.degree. F. and optimizes solvent production. The other stage is within 800.degree.-840.degree. F. and optimizes the C.sub.5 -850.degree. F. product.

  19. Bimetallic promotion of cooperative hydrogen transfer and heteroatom removal in coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Eisch, J.J.

    1991-10-01

    The ultimate objective of this research is to uncover new catalytic processes for the liquefaction of coal and for upgrading coal-derived fuels by removing undesirable organosulfur, organonitrogen and organooxygen constituents. Basic to both the liquefaction of coal and the purification of coal liquids is the transfer of hydrogen from such sources as dihydrogen, metal hydrides or partially reduced aromatic hydrocarbons to the extensive aromatic rings in coal itself or to aromatic sulfides, amines or ethers. Accordingly, this study is exploring how such crucial hydrogen-transfer processes might be catalyzed by soluble, low-valent transition metal complexes and/or Lewis acids under moderate conditions of temperature and pressure. By learning the mechanism whereby H{sub 2}, metal hydrides or partially hydrogenated aromatics do transfer hydrogen to model aromatic compounds, with the aid of homogeneous, bimetallic catalysts, we hope to identify new methods for producing superior fuels from coal.

  20. Bimetallic promotion of cooperative hydrogen transfer and heteroatom removal in coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Eisch, J.J.

    1991-07-01

    The ultimate objective of this research is to uncover new catalytic processes for the liquefaction of coal and for upgrading coal-derived fuels by removing undesirable organosulfur, organonitrogen and organooxygen constituents. Basic to both the liquefaction of coal and the purification of coal liquids is the transfer of hydrogen from such sources as dihydrogen, metal hydrides or partially reduced aromatic hydrocarbons to the extensive aromatic rings in coal itself or to aromatic sulfides, amines or ethers. Accordingly, this study is exploring how such crucial hydrogen-transfer processes might be catalyzed by soluble, low-valent transition metal complexes and/or Lewis acids under moderate conditions of temperature and pressure. By learning the mechanism whereby H{sub 2}, metal hydrides or partially hydrogenated aromatics do transfer hydrogen to model aromatic compounds, with the aid of homogeneous, bimetallic catalysts, we hope to identify new methods for producing superior fuels from coal.

  1. Phosphorylation in hydrogen bacteria.

    Science.gov (United States)

    Bongers, L

    1967-05-01

    The electron-transport system of cell-free extracts obtained from Hydrogenomonas H-20 has been studied with particular reference to phosphorylation associated with the oxyhydrogen reaction. Cell-free preparations of this organism exhibit oxidative phosphorylation with hydrogen and succinate as electron donors. This activity could be uncoupled with a number of agents. Ratios of phosphorylative activity to oxidative activity observed varied from 0.2 to 0.7. Factors affecting the efficiency of phosphorylation were examined. Inhibitor and spectrophotometric studies indicated that phosphorylation with hydrogen as electron donor occurs exclusively at a site in an abbreviated electron transport chain between H(2) and cytochrome b. The possible occurrence of a cytochrome b oxidase and the requirement for a quinone are discussed, as well as the correlation between the abbreviated pathway and the energy generation by the cell. Evidence is presented which indicates that nicotinamide adenine dinucleotide does not participate in the hydrogen oxidation path which is coupled to adenosine triphosphate formation.

  2. Photoelectrochemical hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Rocheleau, R.E.; Miller, E.; Zhang, Z. [Univ. of Hawaii, Honolulu, HI (United States)

    1995-09-01

    The large-scale production of hydrogen utilizing energy provided by a renewable source to split water is one of the most ambitious long-term goals of the U.S. Department of Energy`s Hydrogen Program. Photoelectrochemical devices-direct photoconversion systems utilizing a photovoltaic-type structure coated with water-splitting catalysts-represent a promising option to meet this goal. Direct solar-to-chemical conversion efficiencies greater than 7% and photoelectrode lifetimes of up to 30 hours in 1 molar KOH have been demonstrated in our laboratory using low-cost, amorphous-silicon-based photoelectrodes. Loss analysis models indicate that the DOE`s goal of 10% solar-to-chemical conversion can be met with amorphous-silicon-based structures optimized for hydrogen production. In this report, we describe recent progress in the development of thin-film catalytic/protective coatings, improvements in photoelectrode efficiency and stability, and designs for higher efficiency and greater stability.

  3. Microstructured reactors for hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Aartun, Ingrid

    2005-07-01

    Small scale hydrogen production by partial oxidation (POX) and oxidative steam reforming (OSR) have been studied over Rh-impregnated microchannel Fecralloy reactors and alumina foams. Trying to establish whether metallic microchannel reactors have special advantages for hydrogen production via catalytic POX or OSR with respect to activity, selectivity and stability was of special interest. The microchannel Fecralloy reactors were oxidised at 1000 deg C to form a {alpha}-Al2O3 layer in the channels in order to enhance the surface area prior to impregnation. Kr-BET measurements showed that the specific surface area after oxidation was approximately 10 times higher than the calculated geometric surface area. Approximately 1 mg Rh was deposited in the channels by impregnation with an aqueous solution of RhCl3. Annular pieces (15 mm o.d.,4 mm i.d., 14 mm length) of extruded {alpha}-Al2O3 foams were impregnated with aqueous solutions of Rh(NO3)3 to obtain 0.01, 0.05 and 0.1 wt.% loadings, as predicted by solution uptake. ICP-AES analyses showed that the actual Rh loadings probably were higher, 0.025, 0.077 and 0.169 wt.% respectively. One of the microchannel Fecralloy reactors and all Al2O3 foams were equipped with a channel to allow for temperature measurement inside the catalytic system. Temperature profiles obtained along the reactor axes show that the metallic microchannel reactor is able to minimize temperature gradients as compared to the alumina foams. At sufficiently high furnace temperature, the gas phase in front of the Rh/Al2O3/Frecralloy microchannel reactor and the 0.025 wt.% Rh/Al2O3 foams ignites. Gas phase ignition leads to lower syngas selectivity and higher selectivity to total oxidation products and hydrocarbon by-products. Before ignition of the gas phase the hydrogen selectivity is increased in OSR as compared to POX, the main contribution being the water-gas shift reaction. After gas phase ignition, increased formation of hydrocarbon by

  4. Morbidade entre a pós-biópsia de linfonodo sentinela e a dissecção axilar no câncer de mama Morbidity after sentinel node biopsy and axillary dissection in breast cancer

    Directory of Open Access Journals (Sweden)

    Beatriz Pifano Soares Ferreira

    2008-12-01

    Full Text Available OBJETIVO: O objetivo deste estudo foi avaliar a morbidade cirúrgica pós-biópsia de linfonodo sentinela (BLS ou dissecção axilar com (DA-NP e sem preservação do nervo intercostobraquial (DA-NS. MÉTODOS: Fez-se estudo coorte prospectivo com 108 pacientes divididas em três grupos: BLS (n=35, DA-NP (n=36 e DA-NS (n=37. Foram avaliadas ocorrência de déficit sensorial, dor, linfedema, seroma e infecção no membro superior homolateral à cirurgia. Monofilamentos de Semmes-Weinstein foram usados para avaliar o déficit sensorial, perimetria braquial foi feita para avaliação da presença de linfedema e aplicado questionário de dor. Para análise estatística foram utilizados os testes ANOVA e Kruskal-Wallis. Foi feita análise bivariada e multivariada. RESULTADOS: Pelo menos uma complicação pós-cirúrgica, imediata ou tardia, ocorreu em 45/108 (41,7% pacientes avaliadas. A complicação mais comum foi dor. Houve diferença estatisticamente significante entre os três grupos somente quanto ao déficit sensorial (p=0,04. Dor, linfedema e déficit sensorial ocorreram com maior freqüência no grupo DA-NS. As pacientes dos grupos BLS e DA-NP não apresentaram diferenças estatisticamente significantes para nenhuma das variáveis analisadas. A pesquisa com os monofilamentos mostrou sensibilidade cutânea preservada em 28/35 pacientes do grupo BLS, em 25/36 pacientes do grupo DA-NP e em 10/37 pacientes do grupo DA-NS (pBACKGROUND: The aim of this study was to evaluate the morbidity after sentinel node biopsy (SNB and axillary dissection with (AD-NS or without sparing the intercostobrachial nerve (AD-NOS. Methods: A prospective cohort study was performed on 108 patients divided into three groups: SNB (n=35, AD-NS (n=36 and AD-NOS (n=37. We evaluated the incidence of sensory loss, pain, lymphedema, seroma formation and infection in the arm homolateral to the breast surgery. Semmes-Weinstein monofilaments were used to assess the sensory loss

  5. Lesões do trato gastrointestinal na síndrome da imunodeficiência adquirida: [title]estudo de 45 necrópsias consecutivas Gastrointestinal tract lesions in the acquired immunodeficiency syndrome: study of forty five consecutive necropsies

    Directory of Open Access Journals (Sweden)

    Maria Goretti Freire de Carvalho

    1994-09-01

    Full Text Available Com objetivo de estudar afrequência e etiologia das lesões do tubo digestivo na Síndrome da Imunodeficiência Adquirida (AIDS, foram analisadas retrospectivamente 45 necrópsias consecutivas de pacientes adultos portadores do vírus da AIDS. Lesões macroscópicas e cortes histológicos de amostras da boca à região anal foram estudados, sendo as lâminas coradas por HE, métodos histoquímicos ou imunohistoquímicos. Trinta e sete (82,3 %pacientes apresentaram lesões no tubo digestivo. O local mais freqüente de lesões foi a boca (73,3%, seguido do cólon (55,5%. Lesões múltiplas foram identificadas em 17 (37,7% casos. O diagnóstico mais prevalente foi infecção pelo citomegalovírus (35,7% identificado predominantemente no cólon. Candidíasefoi mais freqüente na boca (26,6% e infecção herpética no esôfago (8,8%. Verificou-se leucoplasiapilosa oral em 16 (35,5% eneoplasias emsete (15,5%. Asneoplasias incluíram quatro sarcomas de Kaposi, dois Carcinomas intramucosos anais e um linfoma gástrico. Os dados do presente estudo confirmam a importância do trato gastrointestinal como sede de alterações patológicas relacionadas à AIDS.This study was designed to evaluate restropectivefy the frequency and etiology of the gastrointestinal (GI lesions in 45 consecutive necropsies of adult patients with Acquired Immunodeficiency Syndrome (AIDS. Gross descriptions and histological sections of the GI tract, from mouth to anus, were reviewed. The slides were H&E stained, and when necessary special stains and immunohistochemicalmethods were also employed. There were lesions in GI tract in 37(82.3% patients; the mouth was the segment mostfrequently involved (73.3% of the cases, followed by the colon (55.5%. Multiple lesions occurred in 17 (37.7% cases. Cytomegalovirus caused colonic lesions in 35.7% of the cases. Candidiasis was observed in 26.6% mainly in the mouth and herpes simplex (8.8% was the important agent of esophageal lesions. Oral

  6. Distrofina na diferenciação das distrofias de duchenne e becker estudo imuno-histoquímico comparado com o estádio clínico, enzimas séricas e biópsia muscular

    Directory of Open Access Journals (Sweden)

    Lineu Cesar Werneck

    1990-12-01

    Full Text Available Foram estudados 55 casos de distrofia muscular progressiva (34 Duchenne, 12 Duchenne com distrofina residual e 9 Becker, comparando idade, época de início e tempo de sintomas, graduação na escala de Vignos e Archibald, níveis de enzimas séricas e presença de distrofina nas biópsias musculares por imunofluorescência. A intensidade dos sintomas, gravidade do quadro clínico, proliferação de tecido ccnjuntivo endomisial e infiltração por tecido adiposo estão inversamente relacionadas à quantidade de distrofina presente nas biópsias e, diretamente, à presença de fibras hipertróficas e fibras angulares escuras atróficas. Nos comentários são abordados alguns aspectos sobre a diferenciação da distrofia muscular de Duchenne e Becker, a distrofina residual nos casos de Duchenne e a importância do teste para o diagnóstico adequado.

  7. Partial Model Checking with ROBDDs

    DEFF Research Database (Denmark)

    Andersen, Henrik Reif; Maretti, Niels; Staunstrup, Jørgen

    1997-01-01

    This paper introduces a technique for localizing model checking of concurrent state-based systems. The technique, called partial model checking, isfully automatic and performs model checking by gradually specializing the specification with respect to the concurrent components one by one...

  8. Bayesian Sparse Partial Least Squares

    NARCIS (Netherlands)

    Vidaurre, D.; Gerven, M.A.J. van; Bielza, C.; Larrañaga, P.; Heskes, T.M.

    2013-01-01

    Partial least squares (PLS) is a class of methods that makes use of a set of latent or unobserved variables to model the relation between (typically) two sets of input and output variables, respectively. Several flavors, depending on how the latent variables or components are computed, have been

  9. mixed type partial differential equation

    Directory of Open Access Journals (Sweden)

    M. Denche

    2003-01-01

    Full Text Available In this paper, we study a mixed problem with integral boundary conditions for a high order partial differential equation of mixed type. We prove the existence and uniqueness of the solution. The proof is based on energy inequality, and on the density of the range of the operator generated by the considered problem.

  10. Variable Selection via Partial Correlation.

    Science.gov (United States)

    Li, Runze; Liu, Jingyuan; Lou, Lejia

    2017-07-01

    Partial correlation based variable selection method was proposed for normal linear regression models by Bühlmann, Kalisch and Maathuis (2010) as a comparable alternative method to regularization methods for variable selection. This paper addresses two important issues related to partial correlation based variable selection method: (a) whether this method is sensitive to normality assumption, and (b) whether this method is valid when the dimension of predictor increases in an exponential rate of the sample size. To address issue (a), we systematically study this method for elliptical linear regression models. Our finding indicates that the original proposal may lead to inferior performance when the marginal kurtosis of predictor is not close to that of normal distribution. Our simulation results further confirm this finding. To ensure the superior performance of partial correlation based variable selection procedure, we propose a thresholded partial correlation (TPC) approach to select significant variables in linear regression models. We establish the selection consistency of the TPC in the presence of ultrahigh dimensional predictors. Since the TPC procedure includes the original proposal as a special case, our theoretical results address the issue (b) directly. As a by-product, the sure screening property of the first step of TPC was obtained. The numerical examples also illustrate that the TPC is competitively comparable to the commonly-used regularization methods for variable selection.

  11. High speed diagnostics for characterization of oxygen / hydrogen rocket injector flowfields

    Science.gov (United States)

    Locke, Justin M.

    Temporally-resolved diagnostics are needed to characterize the highly-turbulent flowfields of rocket engine combustors. Two different high speed diagnostic techniques have been applied successfully to study the combustion and mixing characteristics of single-element shear-coaxial injector flowfield in a rocket combustor. Tunable diode laser absorption spectroscopy (TDLAS) is applied to make in-situ measurements with combusting gas-gas propellants, and high speed imaging incorporating backlighting is applied to combusting and non-combusting liquid-gas and gas-gas propellants. Tunable diode laser absorption spectroscopy has been used to make path-integrated temperature and H2O mole fraction measurements in a gaseous oxygen / gaseous hydrogen uni-element rocket chamber with hot background flow. Four mixture conditions were studied at a nominal chamber pressure of 115 psia. Near infrared diode lasers were utilized to target rovibrational transitions of water vapor, which is created through the combustion processes. Both direct absorption spectroscopy and wavelength modulation spectroscopy with second harmonic normalized by first harmonic (1f-normalized WMS-2 f) techniques were applied, with the harmonic detection technique found to yield the best results. Centerline measurements were made at two axial locations, in the near-injector region and far-field region further downstream. Time-resolved measurements of temperature and H2O mole fraction in the rocket chamber are presented. The TDLAS measurements shows clear differences between the near-injector and downstream measurement locations. Mean path-integrated temperatures and H2O mole fractions in the near-injector region are lower than the downstream measurement location. Fluctuations in path-integrated temperature and H2O mole fraction in the downstream location are significantly greater than the near-injector region. This suggests increased turbulence and larger-scale mixing processes are occurring in the downstream

  12. Wustite-based photoelectrodes with lithium, hydrogen, sodium, magnesium, manganese, zinc and nickel additives

    Science.gov (United States)

    Carter, Emily Ann; Toroker, Maytal Caspary

    2017-08-15

    A photoelectrode, photovoltaic device and photoelectrochemical cell and methods of making are disclosed. The photoelectrode includes an electrode at least partially formed of FeO combined with at least one of lithium, hydrogen, sodium, magnesium, manganese, zinc, and nickel. The electrode may be doped with at least one of lithium, hydrogen, and sodium. The electrode may be alloyed with at least one of magnesium, manganese, zinc, and nickel.

  13. The partial-birth stratagem.

    Science.gov (United States)

    1998-06-01

    In Wisconsin, physicians stopped performing abortions when a Federal District Court Judge refused to issue a temporary restraining order against the state's newly enacted "partial birth" abortion ban that was couched in such vague language it actually covered all abortions. While ostensibly attempting to ban late-term "intact dilation and extraction," the language of the law did not refer to that procedure or to late terms. Instead, it prohibited all abortions in which a physician "partially vaginally delivers a living child, causes the death of the partially delivered child with the intent to kill the child and then completes the delivery of the child." The law also defined "child" as "a human being from the time of fertilization" until birth. It is clear that this abortion ban is unconstitutional under Row v. Wade, and this unconstitutionality is compounded by the fact that the law allowed no exception to protect a woman's health, which is required by Roe for abortion bans after fetal viability. Wisconsin is only one of about 28 states that have enacted similar laws, and only two have restricted the ban to postviability abortions. Many of these laws have been struck down in court, and President Clinton has continued to veto the Federal partial-birth bill. The Wisconsin Judge acknowledged that opponents of the ban will likely prevail when the case is heard, but his action in denying the temporary injunction means that many women in Wisconsin will not receive timely medical care. The partial birth strategy is really only another anti-abortion strategy.

  14. “Aspectos histológicos e imuno-histoquímicos das biópsias de medula óssea avaliadas no período de 2011 a 2013 em dois laboratórios gerais de anatomia patológica: dificuldades, facilidades e conclusões”

    Directory of Open Access Journals (Sweden)

    Maria Cecília Ferro

    2015-10-01

    Full Text Available A biópsia de medula óssea (BMO é parte integrante do estadiamento e seguimento de pacientes hematológicos e, a sua avaliação oferece uma análise precisa da celularidade (relação tecido adiposo/tecido hematopoético, organização topográfica dos diferentes elementos celulares da medula óssea, alterações do estroma (fibrose reticulínica e colagênica, alterações morfológicas/topográficas dos elementos maduros da linhagem megacariocítica e lesões focais (metástases, infiltração por Linfoma Hodgkin e Linfoma não Hodgkin, granulomas.1 Acrescido a este estudo anatomopatológico, a imunohistoquímica, com marcadores celulares na biópsia de medula óssea, fixada em parafina, representa uma poderosa ferramenta de diagnóstico, de forma que seus resultados podem ser facilmente correlacionados com os obtidos por outras técnicas como a citometria de fluxo e, acima de tudo, os achados clínicos.2 No entanto, apesar de todo o avanço tecnológico nos instrumentos usados no estudo anatomopatológico, mesmo os hematopatologistas treinados precisam de informações clínicas hematológicas precisas, oportunidades de inter-relação com os hematologistas e na maioria dos casos de estudo imuno-histoquímico do material em questão.3 O presente trabalho tem como objetivo analisar os resultados dos casos de biópsia de MO nos últimos três anos, comparar os resultados da imuno-histoquímica com os dados da identificação (idade, gênero e das informações clínicas e hematológicas do paciente. Foi feito um levantamento retrospectivo das biópsias de medula óssea em dois laboratórios do município de Sorocaba (Laboratório de Patologia da Faculdade de Ciências Médicas e da Saúde de Sorocaba – FCMS/PUC-SP, e Laboratório de Patologia e Citologia de Sorocaba. Foram analisados 190 resultados de exames anatomopatológicos de Medula Óssea, sendo 51,6% (n=98 de pacientes do sexo feminino e 48,4% (n=92 do sexo masculino. Apenas 141

  15. IPy2BF4/HF-pyridine: a new combination of reagents for the transformation of partially unprotected thioglycosides and n-pentenyl glycosides to glycosyl fluorides.

    Science.gov (United States)

    López, J Cristóbal; Bernal-Albert, Paloma; Uriel, Clara; Valverde, Serafín; Gómez, Ana M

    2007-12-21

    The combination of bis(pyridinium)iodonium (I) tetrafluoroborate (IPy2BF4), and hydrogen fluoride pyridine (HF-py) forms an iodine monofluoride (IF) synthetic equivalent that can be used in the preparation of partially unprotected glycosyl fluorides from partially unprotected n-pentenyl glycosides and thioglycosides, thus avoiding the need for the protection/deprotection steps normally required in that transformation.

  16. Handheld hydrogen - a new concept for hydrogen storage

    DEFF Research Database (Denmark)

    Johannessen, Tue; Sørensen, Rasmus Zink

    2005-01-01

    A method of hydrogen storage using metal ammine complexes in combination with an ammonia decomposition catalyst is presented. This dense hydrogen storage material has high degree of safety compared to all the other available alternatives. This technology reduces the safety hazards of using liquid...... ammonia and benefits from the properties of ammonia as a fuel. The system can be used as a safe, reversible, low-cost hydrogen carrier....

  17. Effects of Hydrogen-Rich Saline on Hepatectomy-Induced Postoperative Cognitive Dysfunction in Old Mice.

    Science.gov (United States)

    Tian, Yue; Guo, Shanbin; Zhang, Yan; Xu, Ying; Zhao, Ping; Zhao, Xiaochun

    2017-05-01

    This study aims to investigate the protective effects and underlying mechanisms of hydrogen-rich saline on the cognitive functions of elder mice with partial hepatectomy-induced postoperative cognitive dysfunction (POCD). Ninety-six old male Kunming mice were randomly divided into 4 groups (n = 24 each): control group (group C), hydrogen-rich saline group (group H), POCD group (group P), and POCD + hydrogen-rich saline group (group PH). Cognitive function was subsequently assessed using Morris water-maze (MWM) test. TNF-α and IL-1β levels were measured by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry, along with NF-κB activity determined by ELISA. The morphology of hippocampal tissues were further observed by HE staining. Learning and memory abilities of mice were significantly impaired at day 10 and day 14 post-surgery, as partial hepatectomy significantly prolonged the escape latency, decreased time at the original platform quadrant and frequency of crossing in group P when compared to group C (p hydrogen-rich saline (group PH) partially rescued spatial memory and learning as it shortened escape latency and increased time and crossing frequency of original platform compared to group P (p hydrogen-rich saline. Hydrogen-rich saline can alleviate POCD via inhibiting NF-κB activity in the hippocampus and reducing inflammatory response.

  18. Hydrogenation of o-cresol on platinum catalyst: Catalytic experiments and first-principles calculations

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yaping [Department of Physics and Engineering Physics, The University of Tulsa, Tulsa, OK 74104 (United States); Liu, Zhimin [School of Chemical, Biological and Materials Engineering, University of Oklahoma, Norman, OK 73019 (United States); Xue, Wenhua [Department of Physics and Engineering Physics, The University of Tulsa, Tulsa, OK 74104 (United States); Crossley, Steven P.; Jentoft, Friederike C. [School of Chemical, Biological and Materials Engineering, University of Oklahoma, Norman, OK 73019 (United States); Wang, Sanwu, E-mail: sanwu-wang@utulsa.edu [Department of Physics and Engineering Physics, The University of Tulsa, Tulsa, OK 74104 (United States)

    2017-01-30

    Highlights: • Hydrogenation of o-cresol over Pt results in formation of two products. • Dissociation of hydrogen from the −OH group involves a low activation energy. • Following hydrogenation of the aromatic ring forms 2-methyl-cyclohexanone. • Further hydrogenation produces the final product, 2-methyl-cyclohexanol. - Abstract: Catalytic experiments were performed for the hydrogenation of o-cresol in n-dodecane over a platinum catalyst. Batch reactions analyzed with an in-situ ATR IR probe suggest that the hydrogenation results in the formation of the final product, 2-methyl-cyclohexanol, with 2-methyl-cyclohexanone as the intermediate product. Ab initio density-functional theory was employed to investigate the atomic-scale mechanism of o-cresol hydrogenation on the Pt(111) surface. The formation of 2-methyl-cyclohexanone was found to involve two steps. The first step is a hydrogen abstraction, that is, the H atom in the hydroxyl group migrates to the Pt surface. The second step is hydrogenation, that is, the pre-existing H atoms on Pt react with the carbon atoms in the aromatic ring. On the other hand, 2-methyl-cyclohexanonol may be produced through two paths, with activation energies slightly greater than that for the formation of 2-methyl-cyclohexanone. One path involves direct hydrogenation of the aromatic ring. Another path involves three steps, with the partial hydrogenation of the ring as the first step, hydrogen abstraction of the −OH group as the second, and hydrogenation of remaining C atoms and the O atom the last.

  19. Hydrogen application dynamics and networks

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, E. [Air Liquide Large Industries, Champigny-sur-Marne (France)

    2010-12-30

    The Chemical Industry consumes large volumes of hydrogen as raw material for the manufacture of numerous products (e.g. polyamides and polyurethanes account for 60% of hydrogen demand). The hydrogen demand was in the recent past and will continue to be driven by the polyurethane family. China will host about 60% of new hydrogen needs over the period 2010-2015 becoming the first hydrogen market next year and reaching 25% of market share by 2015 (vs. only 4% in 2001). Air Liquide supplies large volumes of Hydrogen (and other Industrial Gases) to customers by on-site plants and through pipeline networks which offer significant benefits such as higher safety, reliability and flexibility of supply. Thanks to its long term strategy and heavy investment in large units and pipeline networks, Air Liquide is the Industrial Gas leader in most of the world class Petrochemical basins (Rotterdam, Antwerp, US Gulf Coast, Yosu, Caojing,..) (orig.)

  20. Hydrogen ICE Vehicle Testing Activities

    Energy Technology Data Exchange (ETDEWEB)

    J. Francfort; D. Karner

    2006-04-01

    The Advanced Vehicle Testing Activity teamed with Electric Transportation Applications and Arizona Public Service to develop and monitor the operations of the APS Alternative Fuel (Hydrogen) Pilot Plant. The Pilot Plant provides 100% hydrogen, and hydrogen and compressed natural gas (H/CNG)-blended fuels for the evaluation of hydrogen and H/CNG internal combustion engine (ICE) vehicles in controlled and fleet testing environments. Since June 2002, twenty hydrogen and H/CNG vehicles have accumulated 300,000 test miles and 5,700 fueling events. The AVTA is part of the Department of Energy’s FreedomCAR and Vehicle Technologies Program. These testing activities are managed by the Idaho National Laboratory. This paper discusses the Pilot Plant design and monitoring, and hydrogen ICE vehicle testing methods and results.

  1. Preparation of slightly hydrogenated coal

    Energy Technology Data Exchange (ETDEWEB)

    Rank, V.

    1943-05-03

    Processes serving as producers of slightly hydrogenated coal are discussed. It was established that the working process of an extracting hydrogenation from coal alone did not present optimal conditions for production of slightly hydrogenated coal, and therefore led to unfavorably high costs. More favorable operating costs were expected with the use of larger amounts of gas or with simultaneous production of asphalt-free oils in larger quantity. The addition of coal into the hydrogenation of low temperature carbonization tars made it possible to produce additional briquetting material (slightly hydrogenated coal) in the same reaction space without impairment of the tar hydrogenation. This was to lower the cost still more. For reasons of heat exchange, the process with a cold separator was unfavorable, and consideration of the residue quality made it necessary to investigate how high the separator temperature could be raised. 3 tables.

  2. Hydrogen-enriched fuels

    Energy Technology Data Exchange (ETDEWEB)

    Roser, R. [NRG Technologies, Inc., Reno, NV (United States)

    1998-08-01

    NRG Technologies, Inc. is attempting to develop hardware and infrastructure that will allow mixtures of hydrogen and conventional fuels to become viable alternatives to conventional fuels alone. This commercialization can be successful if the authors are able to achieve exhaust emission levels of less than 0.03 g/kw-hr NOx and CO; and 0.15 g/kw-hr NMHC at full engine power without the use of exhaust catalysts. The major barriers to achieving these goals are that the lean burn regimes required to meet exhaust emissions goals reduce engine output substantially and tend to exhibit higher-than-normal total hydrocarbon emissions. Also, hydrogen addition to conventional fuels increases fuel cost, and reduces both vehicle range and engine output power. Maintaining low emissions during transient driving cycles has not been demonstrated. A three year test plan has been developed to perform the investigations into the issues described above. During this initial year of funding research has progressed in the following areas: (a) a cost effective single-cylinder research platform was constructed; (b) exhaust gas speciation was performed to characterize the nature of hydrocarbon emissions from hydrogen-enriched natural gas fuels; (c) three H{sub 2}/CH{sub 4} fuel compositions were analyzed using spark timing and equivalence ratio sweeping procedures and finally; (d) a full size pick-up truck platform was converted to run on HCNG fuels. The testing performed in year one of the three year plan represents a baseline from which to assess options for overcoming the stated barriers to success.

  3. Tetraphenylphosphonium hydrogen oxalate

    Directory of Open Access Journals (Sweden)

    Philip A. W. Dean

    2008-01-01

    Full Text Available In the title compound, C24H20P+·C2HO4−, two symmetry-independent ion pairs are present. The cations aggregate into puckered sheets via zigzag infinite chains of sixfold phenyl embraces and parallel fourfold phenyl embraces, while the anions form hydrogen-bonded chains between the sheets of cations. In the two independent oxalate anions, the angles between the normals to the two least-squares carboxylate COO planes are unusually large, viz. 72.5 (1 and 82.1 (1°.

  4. Recirculating cryogenic hydrogen maser

    Energy Technology Data Exchange (ETDEWEB)

    Huerlimann, M.D.; Hardy, W.N.; Berlinsky, A.J.; Cline, R.W.

    1986-08-01

    We report on the design and initial testing of a new type of hydrogen maser, operated at dilution refrigerator temperatures, in which H atoms circulate back and forth between a microwave-pumped state selector and the maser cavity. Other novel design features include liquid-/sup 4/He-coated walls, He-cooled electronics, and the use of microscopic magnetic particles to relax the two lowest hyperfine levels in the state selector. Stabilities at least as good as that of a Rb clock and a high-stability quartz oscillator are observed for measuring times between 1 and 300 s.

  5. Hydrogen storage development

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, G.J.; Guthrie, S.E. [Sandia National Labs., Livermore, CA (United States)

    1998-08-01

    A summary of the hydride development efforts for the current program year (FY98) are presented here. The Mg-Al-Zn alloy system was studied at low Zn levels (2--4 wt%) and midrange Al contents (40--60 wt%). Higher plateau pressures were found with Al and Zn alloying in Mg and, furthermore, it was found that the hydrogen desorption kinetics were significantly improved with small additions of Zn. Results are also shown here for a detailed study of the low temperature properties of Mg{sub 2}NiH{sub 4}, and a comparison made between conventional melt cast alloy and the vapor process material.

  6. Partial Cooperative Equilibria: Existence and Characterization

    Directory of Open Access Journals (Sweden)

    Amandine Ghintran

    2010-09-01

    Full Text Available We study the solution concepts of partial cooperative Cournot-Nash equilibria and partial cooperative Stackelberg equilibria. The partial cooperative Cournot-Nash equilibrium is axiomatically characterized by using notions of rationality, consistency and converse consistency with regard to reduced games. We also establish sufficient conditions for which partial cooperative Cournot-Nash equilibria and partial cooperative Stackelberg equilibria exist in supermodular games. Finally, we provide an application to strategic network formation where such solution concepts may be useful.

  7. The marketing of partial hospitalization.

    Science.gov (United States)

    Millsap, P; Brown, E; Kiser, L; Pruitt, D

    1987-09-01

    Health-care professionals are currently operating in the context of a rapidly changing health-care delivery system, including the move away from inpatient services to outpatient services in order to control costs. Those who practice in partial-hospital settings are in a position to offer effective, cost-efficient services; however, there continue to be obstacles which hinder appropriate utilization of the modality. The development and use of a well-designed marketing plan is one strategy for removing these obstacles. This paper presents a brief overview of the marketing process, ideas for developing a marketing plan, and several examples of specific marketing strategies as well as ways to monitor their effectiveness. Partial-hospital providers must take an active role in answering the calls for alternative sources of psychiatric care. A comprehensive, education-oriented marketing approach will increase the public's awareness of such alternatives and enable programs to survive in a competitive environment.

  8. Dynamics of partial differential equations

    CERN Document Server

    Wayne, C Eugene

    2015-01-01

    This book contains two review articles on the dynamics of partial differential equations that deal with closely related topics but can be read independently. Wayne reviews recent results on the global dynamics of the two-dimensional Navier-Stokes equations. This system exhibits stable vortex solutions: the topic of Wayne's contribution is how solutions that start from arbitrary initial conditions evolve towards stable vortices. Weinstein considers the dynamics of localized states in nonlinear Schrodinger and Gross-Pitaevskii equations that describe many optical and quantum systems. In this contribution, Weinstein reviews recent bifurcations results of solitary waves, their linear and nonlinear stability properties, and results about radiation damping where waves lose energy through radiation.   The articles, written independently, are combined into one volume to showcase the tools of dynamical systems theory at work in explaining qualitative phenomena associated with two classes of partial differential equ...

  9. Introduction to partial differential equations

    CERN Document Server

    Borthwick, David

    2016-01-01

    This modern take on partial differential equations does not require knowledge beyond vector calculus and linear algebra. The author focuses on the most important classical partial differential equations, including conservation equations and their characteristics, the wave equation, the heat equation, function spaces, and Fourier series, drawing on tools from analysis only as they arise.Within each section the author creates a narrative that answers the five questions: (1) What is the scientific problem we are trying to understand? (2) How do we model that with PDE? (3) What techniques can we use to analyze the PDE? (4) How do those techniques apply to this equation? (5) What information or insight did we obtain by developing and analyzing the PDE? The text stresses the interplay between modeling and mathematical analysis, providing a thorough source of problems and an inspiration for the development of methods.

  10. Removable partial dentures: clinical concepts.

    Science.gov (United States)

    Bohnenkamp, David M

    2014-01-01

    This article provides a review of the traditional clinical concepts for the design and fabrication of removable partial dentures (RPDs). Although classic theories and rules for RPD designs have been presented and should be followed, excellent clinical care for partially edentulous patients may also be achieved with computer-aided design/computer-aided manufacturing technology and unique blended designs. These nontraditional RPD designs and fabrication methods provide for improved fit, function, and esthetics by using computer-aided design software, composite resin for contours and morphology of abutment teeth, metal support structures for long edentulous spans and collapsed occlusal vertical dimensions, and flexible, nylon thermoplastic material for metal-supported clasp assemblies. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Renewable hydrogen production via thermochemical/electrochemical coupling

    Energy Technology Data Exchange (ETDEWEB)

    Ambrosini, Andrea [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Babiniec, Sean Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Miller, James E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-10-01

    A coupled electrochemical/thermochemical cycle was investigated to produce hydrogen from renewable resources. Like a conventional thermochemical cycle, this cycle leverages chemical energy stored in a thermochemical working material that is reduced thermally by solar energy. However, in this concept, the stored chemical energy only needs to be partially, but not fully, capable of splitting steam to produce hydrogen. To complete the process, a proton-conducting membrane is driven to separate hydrogen as it is produced, thus shifting the thermodynamics toward further hydrogen production. This novel coupled-cycle concept provides several benefits. First, the required oxidation enthalpy of the reversible thermochemical material is reduced, enabling the process to occur at lower temperatures. Second, removing the requirement for spontaneous steam-splitting widens the scope of materials compositions, allowing for less expensive/more abundant elements to be used. Lastly, thermodynamics calculations suggest that this concept can potentially reach higher efficiencies than photovoltaic-to-electrolysis hydrogen production methods. This Exploratory Express LDRD involved assessing the practical feasibility of the proposed coupled cycle. A test stand was designed and constructed and proton-conducting membranes were synthesized. While the full proof of concept was not achieved, the individual components of the experiment were validated and new capabilities that can be leveraged by a variety of programs were developed.

  12. Probing skin interaction with hydrogen peroxide using diffuse reflectance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Zonios, George [Department of Materials Science and Engineering, University of Ioannina, 45110 Ioannina (Greece); Dimou, Aikaterini [Department of Materials Science and Engineering, University of Ioannina, 45110 Ioannina (Greece); Galaris, Dimitrios [Laboratory of Biological Chemistry, School of Medicine, University of Ioannina, 45110 Ioannina (Greece)

    2008-01-07

    Hydrogen peroxide is an important oxidizing agent in biological systems. In dermatology, it is frequently used as topical antiseptic, it has a haemostatic function, it can cause skin blanching, and it can facilitate skin tanning. In this work, we investigated skin interaction with hydrogen peroxide, non-invasively, using diffuse reflectance spectroscopy. We observed transient changes in the oxyhaemoglobin and deoxyhaemoglobin concentrations as a result of topical application of dilute H{sub 2}O{sub 2} solutions to the skin, with changes in deoxyhaemoglobin concentration being more pronounced. Furthermore, we did not observe any appreciable changes in melanin absorption properties as well as in the skin scattering properties. We also found no evidence for production of oxidized haemoglobin forms. Our observations are consistent with an at least partial decomposition of hydrogen peroxide within the stratum corneum and epidermis, with the resulting oxygen and/or remaining hydrogen peroxide inducing vasoconstriction to dermal blood vessels and increasing haemoglobin oxygen saturation. An assessment of the effects of topical application of hydrogen peroxide to the skin may serve as the basis for the development of non-invasive techniques to measure skin antioxidant capacity and also may shed light onto skin related disorders such as vitiligo.

  13. Materials for the scavenging of hydrogen at high temperatures

    Science.gov (United States)

    Shepodd, T.J.; Phillip, B.L.

    1997-04-29

    A hydrogen getter composition is described comprising a double or triple bonded hydrocarbon with a high melting point useful for removing hydrogen gas, to partial pressures below 0.01 torr, from enclosed spaces and particularly from vessels used for transporting or containing fluids at elevated temperatures. The hydrogen getter compositions disclosed herein and their reaction products will neither melt nor char at temperatures in excess of 100C. They possess significant advantages over conventional hydrogen getters, namely low risk of fire or explosion, no requirement for high temperature activation or operation, the ability to absorb hydrogen even in the presence of contaminants such as water, water vapor, common atmospheric gases and oil mists and are designed to be disposed within the confines of the apparatus. These getter materials can be mixed with binders, such as fluoropolymers, which permit the getter material to be fabricated into useful shapes and/or impart desirable properties such as water repellency or impermeability to various gases. 7 figs.

  14. National Hydrogen Roadmap Workshop Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    None

    2002-04-01

    This document summarizes the presentations and suggestions put forth by officials, industry experts and policymakers in their efforts to come together to develop a roadmap for America''s clean energy future and outline the key barriers and needs to achieve the hydrogen vision. The National Hydrogen Roadmap Workshop was held April 2-3, 2002. These proceedings were compiled into a formal report, The National Hydrogen Energy Roadmap, which is also available online.

  15. The Montreal hydrogen airport project

    Energy Technology Data Exchange (ETDEWEB)

    Bose, T.K. [Hydrogen Research Inst., Trois-Rivieres, Quebec (Canada)

    2004-07-01

    'Full text:' The transition to a hydrogen economy presents a unique opportunity for Canada. It spells growth and investment opportunities for Canadian industry and offers a sustainable solution to climate change and pollution, particularly in our cities. The H{sub 2}EA program set forth by the government of Canada fosters the development and early introduction into the market place in Canada of multiple hydrogen technologies that support the transition to a hydrogen economy. A group of leading suppliers, manufacturers and users of hydrogen and hydrogen compatible technologies intend to demonstrate various applications for hydrogen in the area of power generation and transportation. The project will take place at the Pierre-Elliot-Trudeau Airport in Montreal in collaboration with Aeroport de Montreal (ADM). ADM has already invested approximately $50 million in environment related initiatives and The Montreal Hydrogen Airport project will further demonstrate its leadership in this area. The project will be divided into 14 sub-projects, which are: 1. Hydrogen internal combustion engine (HICE) shuttle buses. 2. Fuel cell shuttle bus. 3. Air terminal people movers powered by H2 fuel cell technologies. 4. HICE powered tugs and luggage carts. 5. H2 fuelling station. 6. H2 filling station. 7. Mobile hydrogen auxiliary power units for ADM vehicles. 8. Stationary hydrogen auxiliary power units for airport facilities. 9. ADM truck conversion to HICE. 10. Maintenance and certification centre. 11. Project promotion. 12. Training. 13. Compliance testing and project impact analysis. 14. Project management. This project is undoubtedly ambitious and yet realistic. Set in the second largest airport in the country, it can play the double role of showcasing the Canadian hydrogen industry to the entire world while implementing the strategic elements of the hydrogen economy in the second largest population centre in Canada. (author)

  16. Partial oral treatment of endocarditis

    DEFF Research Database (Denmark)

    Iversen, Kasper; Høst, Nis; Bruun, Niels Eske

    2013-01-01

    Guidelines for the treatment of left-sided infective endocarditis (IE) recommend 4 to 6 weeks of intravenous antibiotics. Conversion from intravenous to oral antibiotics in clinically stabilized patients could reduce the side effects associated with intravenous treatment and shorten the length...... of hospital stay. Evidence supporting partial oral therapy as an alternative to the routinely recommended continued parenteral therapy is scarce, although observational data suggest that this strategy may be safe and effective....

  17. Hydrogen transport membranes for dehydrogenation reactions

    Science.gov (United States)

    Balachandran,; Uthamalingam, [Hinsdale, IL

    2008-02-12

    A method of converting C.sub.2 and/or higher alkanes to olefins by contacting a feedstock containing C.sub.2 and/or higher alkanes with a first surface of a metal composite membrane of a sintered homogenous mixture of an Al oxide or stabilized or partially stabilized Zr oxide ceramic powder and a metal powder of one or more of Pd, Nb, V, Zr, Ta and/or alloys or mixtures thereof. The alkanes dehydrogenate to olefins by contact with the first surface with substantially only atomic hydrogen from the dehydrogenation of the alkanes passing through the metal composite membrane. Apparatus for effecting the conversion and separation is also disclosed.

  18. Proton tunnelling in intermolecular hydrogen bonds

    Energy Technology Data Exchange (ETDEWEB)

    Horsewill, A.J. [Nottingham Univ. (United Kingdom); Johnson, M.R. [Institut Max von Laue - Paul Langevin (ILL), 38 - Grenoble (France); Trommsdorff, H.P. [Grenoble-1 Univ., 38 (France)

    1997-04-01

    The wavefunctions of particles extend beyond the classically accessible regions of potential energy-surfaces (PES). A manifestation of this partial delocalization is the quantum-mechanical tunneling effect which enables a particle to escape from a metastable potential-well. Tunnelling is most important for the lightest atoms, so that the determination of its contribution to proton transfer, one of the most fundamental chemical reactions, is an important issue. QENS and NMR techniques have been employed to study the motion of protons in the hydrogen bond of benzoic-acid crystals, a system which has emerged as a particularly suitable model since proton transfer occurs in a near symmetric double-well potential. The influence of quantum tunnelling was revealed and investigated in these experiments. This work provides an experimental benchmark for theoretical descriptions of translational proton-tunnelling. (author). 7 refs.

  19. Management of partial traumatic hemipelvectomy.

    Science.gov (United States)

    Wang, Guodong; Zhou, Dongsheng; Shen, Wun-Jer; Xin, Maoyuan; He, Jiliang; Li, Qinghu; Tan, Guoqing

    2013-11-01

    Partial traumatic hemipelvectomy is a devastating condition. Although by definition the affected limb is not totally transected from the trunk because of retained soft tissue, the reported mortality rate is actually higher than in complete traumatic hemipelvectomy. Between January 2000 and December 2011, a total of 917 patients were admitted to the authors' institution for pelvic fracture. Seven of these patients met the criteria for partial traumatic hemipelvectomy. All 7 patients had multiple associated injuries and met the criteria for Baskett class IV hypovolemic shock on arrival at the emergency department. The amount of bleeding was the greatest issue, and control of hemorrhage and rapid blood transfusion were the initial goals. Abdominal aorta balloon occlusion, laparotomy and packing, and pelvic external fixation were useful to control bleeding. Two patients died during the initial resuscitation phase. Angiography (digital subtraction or computed tomographic) was performed in 4 patients but did not provide any treatment-altering information. Limb preservation was attempted in 2 patients; both of these patients eventually required hindquarter amputation. One patient died, and the second patient survived after a difficult postoperative course. The best results were obtained in 3 patients who underwent completion of the hindquarter amputation within 24 hours of trauma. All patients became wheelchair dependent, and no patient was able to return to work. Early completion of hindquarter amputation after hemorrhaging has been controlled is recommended in patients with partial traumatic hemipelvectomy. Angiography did not prove useful in decision making. Copyright 2013, SLACK Incorporated.

  20. Partially composite Goldstone Higgs boson

    Science.gov (United States)

    Alanne, Tommi; Franzosi, Diogo Buarque; Frandsen, Mads T.

    2017-11-01

    We consider a model of dynamical electroweak symmetry breaking with a partially composite Goldstone Higgs boson. The model is based on a strongly interacting fermionic sector coupled to a fundamental scalar sector via Yukawa interactions. The SU (4 )×SU (4 ) global symmetry of these two sectors is broken to a single SU(4) via Yukawa interactions. Electroweak symmetry breaking is dynamically induced by condensation due to the strong interactions in the new fermionic sector which further breaks the global symmetry SU (4 )→Sp (4 ). The Higgs boson arises as a partially composite state which is an exact Goldstone boson in the limit where SM interactions are turned off. Terms breaking the SU(4) global symmetry explicitly generate a mass for the Goldstone Higgs boson. The model realizes in different limits both (partially) composite Higgs and (bosonic) technicolor models, thereby providing a convenient unified framework for phenomenological studies of composite dynamics. It is also a dynamical extension of the recent elementary Goldstone Higgs model.

  1. [Benign partial epilepsies of childhood].

    Science.gov (United States)

    Palencia, R

    To carry out, by means of a literature review, an update of the entities that can be included within the group of benign partial epilepsies of childhood. Among partial epilepsies with onset in the first stages of life, a group extended in the last years with a favourable course and a trend to reverse, even spontaneously, has been identified. Some of these entities have a genetic origin but we do not know the mechanisms by which these epilepsies show a self limited course, which have given rise to the denomination of epilepsy that comes and goes; nevertheless, an evolution to other more complex forms is also possible. Benign partial epilepsies of childhood constitute a wide group of conditions of varied semiology, usually with a good prognosis even without treatment. Occasionally, these epilepsies may show a more unfavourable course with a worsening, in spite of medication, and the appearance of neurologic and neuropsychologic disorders. All these aspects must be known and considered by the physician in charge of these patients management.

  2. Hydrogen fracture toughness tester completion

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-09-30

    The Hydrogen Fracture Toughness Tester (HFTT) is a mechanical testing machine designed for conducting fracture mechanics tests on materials in high-pressure hydrogen gas. The tester is needed for evaluating the effects of hydrogen on the cracking properties of tritium reservoir materials. It consists of an Instron Model 8862 Electromechanical Test Frame; an Autoclave Engineering Pressure Vessel, an Electric Potential Drop Crack Length Measurement System, associated computer control and data acquisition systems, and a high-pressure hydrogen gas manifold and handling system.

  3. Catalyzed borohydrides for hydrogen storage

    Science.gov (United States)

    Au, Ming [Augusta, GA

    2012-02-28

    A hydrogen storage material and process is provided in which alkali borohydride materials are created which contain effective amounts of catalyst(s) which include transition metal oxides, halides, and chlorides of titanium, zirconium, tin, and combinations of the various catalysts. When the catalysts are added to an alkali borodydride such as a lithium borohydride, the initial hydrogen release point of the resulting mixture is substantially lowered. Additionally, the hydrogen storage material may be rehydrided with weight percent values of hydrogen at least about 9 percent.

  4. Hydrogen storage in carbon nanotubes.

    Science.gov (United States)

    Hirscher, M; Becher, M

    2003-01-01

    The article gives a comprehensive overview of hydrogen storage in carbon nanostructures, including experimental results and theoretical calculations. Soon after the discovery of carbon nanotubes in 1991, different research groups succeeded in filling carbon nanotubes with some elements, and, therefore, the question arose of filling carbon nanotubes with hydrogen by possibly using new effects such as nano-capillarity. Subsequently, very promising experiments claiming high hydrogen storage capacities in different carbon nanostructures initiated enormous research activity. Hydrogen storage capacities have been reported that exceed the benchmark for automotive application of 6.5 wt% set by the U.S. Department of Energy. However, the experimental data obtained with different methods for various carbon nanostructures show an extreme scatter. Classical calculations based on physisorption of hydrogen molecules could not explain the high storage capacities measured at ambient temperature, and, assuming chemisorption of hydrogen atoms, hydrogen release requires temperatures too high for technical applications. Up to now, only a few calculations and experiments indicate the possibility of an intermediate binding energy. Recently, serious doubt has arisen in relation to several key experiments, causing considerable controversy. Furthermore, high hydrogen storage capacities measured for carbon nanofibers did not survive cross-checking in different laboratories. Therefore, in light of today's knowledge, it is becoming less likely that at moderate pressures around room temperature carbon nanostructures can store the amount of hydrogen required for automotive applications.

  5. An effective finite element model for the prediction of hydrogen induced cracking in steel pipelines

    KAUST Repository

    Traidia, Abderrazak

    2012-11-01

    This paper presents a comprehensive finite element model for the numerical simulation of Hydrogen Induced Cracking (HIC) in steel pipelines exposed to sulphurous compounds, such as hydrogen sulphide (H2S). The model is able to mimic the pressure build-up mechanism related to the recombination of atomic hydrogen into hydrogen gas within the crack cavity. In addition, the strong couplings between non-Fickian hydrogen diffusion, pressure build-up and crack extension are accounted for. In order to enhance the predictive capabilities of the proposed model, problem boundary conditions are based on actual in-field operating parameters, such as pH and partial pressure of H 2S. The computational results reported herein show that, during the extension phase, the propagating crack behaves like a trap attracting more hydrogen, and that the hydrostatic stress field at the crack tip speed-up HIC related crack initiation and growth. In addition, HIC is reduced when the pH increases and the partial pressure of H2S decreases. Furthermore, the relation between the crack growth rate and (i) the initial crack radius and position, (ii) the pipe wall thickness and (iii) the fracture toughness, is also evaluated. Numerical results agree well with experimental data retrieved from the literature. Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

  6. Memorandum on coal hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Struss

    1942-10-27

    The first test facility was built in Ludwigshafen in Building 35 in 1924. During the Technical Committee meeting of February 4, 1926, Carl Bosch reported briefly for the first time on the status of coal hydrogenation and promised a comprehensive report to follow. Next, in connection with the Technical Committee meeting of July 13, 1926, Bosch arranged for the Committee to tour the test facility. Subsequently, the first industrial facility, for a yearly output of 100,000 tons, was built in Leuna with great speed and began production in April 1927. For this facility RM 26.6 million in credit was appropriated during 1926 and 1927 (the costs, including associated units, were estimated at RM 46 million; the RM 26.6 million covered only erection of the plant). A further RM 264 million was written off to hydrogenation in the years 1926 to 1931 on tests in new areas. At the end of 1929 the large scale tests at Merseburg were interrupted. On April 7, 1932, in the Nitrogen Branch discussion at Ludwigshafen, Dr. Schneider reported on the improvement in coal decomposition percentage which had meanwhile been achieved: from 60% to 95%. He proposed a last large-scale test, which was to require RM 375,000 up to the starting point and RM 170,000 per month during the six-month test period. This last test then led to definitive success in 1933.

  7. Possibility of hydrogen supply by shared residential fuel cell systems for fuel cell vehicles

    Directory of Open Access Journals (Sweden)

    Ono Yusuke

    2017-01-01

    Full Text Available Residential polymer electrolyte fuel cells cogeneration systems (residential PEFC systems produce hydrogen from city gas by internal gas-reformer, and generate electricity, the hot water at the same time. From the viewpoint of the operation, it is known that residential PEFC systems do not continuously work but stop for long time, because the systems generate enough hot water for short operation time. In other words, currently residential PEFC systems are dominated by the amount of hot water demand. This study focuses on the idle time of residential PEFC systems. Since their gas-reformers are free, the systems have potential to produce hydrogen during the partial load operations. The authors expect that residential PEFC systems can take a role to supply hydrogen for fuel cell vehicles (FCVs before hydrogen fueling stations are distributed enough. From this perspective, the objective of this study is to evaluate the hydrogen production potential of residential PEFC systems. A residential PEFC system was modeled by the mixed integer linear programming to optimize the operation including hydrogen supply for FCV. The objective function represents annual system cost to be minimized with the constraints of energy balance. It should be noted that the partial load characteristics of the gas-reformer and the fuel cell stack are taken into account to derive the optimal operation. The model was employed to estimate the possible amount of hydrogen supply by a residential PEFC system. The results indicated that the system could satisfy at least hydrogen demand for transportation of 8000 km which is as far as the average annual mileage of a passenger car in Japan. Furthermore, hydrogen production by sharing a residential PEFC system with two households is more effective to reduce primary energy consumption with hydrogen supply for FCV than the case of introducing PEFC in each household.

  8. Versatile Hydrogen-Hydrogen Bond with a Difference

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 6. Versatile Hydrogen-Hydrogen Bond with a Difference. A G Samuelson. Research News Volume 1 Issue 6 June 1996 pp 87-89. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/001/06/0087-0089 ...

  9. Hydrogen and fuel cells; Hydrogene et piles a combustible

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-06-15

    This road-map proposes by the Group Total aims to inform the public on the hydrogen and fuel cells. It presents the hydrogen technology from the production to the distribution and storage, the issues as motor fuel and fuel cells, the challenge for vehicles applications and the Total commitments in the domain. (A.L.B.)

  10. Novel developments in hydrogen storage, hydrogen activation and ionic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Doroodian, Amir

    2010-12-03

    This dissertation is divided into three chapters. Recently, metal-free hydrogen activation using phosphorous compounds has been reported in science magazine. We have investigated the interaction between hydrogen and phosphorous compounds in presence of strong Lewis acids (chapter one). A new generation of metal-free hydrogen activation, using amines and strong Lewis acids with sterically demanding nature, was already developed in our group. Shortage of high storage capacity using large substitution to improve sterical effect led us to explore the amine borane derivatives, which are explained in chapter two. Due to the high storage capacity of hydrogen in aminoborane derivatives, we have explored these materials to extend hydrogen release. These compounds store hydrogen as proton and hydride on adjacent atoms or ions. These investigations resulted in developing hydrogen storage based on ionic liquids containing methyl guanidinium cation. Then we have continued to develop ionic liquids based on methyl guanidinium cation with different anions, such as tetrafluoro borate (chapter three). We have replaced these anions with transition metal anions to investigate hydrogen bonding and catalytic activity of ionic liquids. This chapter illustrates the world of ionic liquid as a green solvent for organic, inorganic and catalytic reactions and combines the concept of catalysts and solvents based on ionic liquids. The catalytic activity is investigated particularly with respect to the interaction with CO{sub 2}. (orig.)

  11. Hydrogen vacancies facilitate hydrogen transport kinetics in sodium hydride nanocrystallites

    NARCIS (Netherlands)

    Singh, S.; Eijt, S.W.H.

    2008-01-01

    We report ab initio calculations based on density-functional theory, of the vacancy-mediated hydrogen migration energy in bulk NaH and near the NaH(001) surface. The estimated rate of the vacancy mediated hydrogen transport, obtained within a hopping diffusion model, is consistent with the reaction

  12. Muonium/muonic hydrogen formation in atomic hydrogen

    Indian Academy of Sciences (India)

    Abstract. The muonium/muonic hydrogen atom formation in µ±–H collisions is in- vestigated, using a two-state approximation in a time dependent formalism. It is found that muonium cross-section results are similar to the cross-section results obtained for positronium formation in e+–H collision. Muonic hydrogen atom ...

  13. Experiência preliminar com um novo método de biópsia aspirativa guiada por ecografia endoscópica transbrônquica no diagnóstico de lesões mediastínicas e hilares

    Directory of Open Access Journals (Sweden)

    M. Krasnik

    2004-03-01

    Full Text Available RESUMO: O correcto estadiamento do cancro do pulmão é fundamental, não só na determinação do prognóstico mas também na orientação terapêutica.A avaliação da extensão tumoral ao mediastino, por invasão directa ou metastática ganglionar, é um dos passos deste estadiamento. A TAC torácica é falível na detecção de metástases ganglionares, sendo o exame anatomopatológico mais fidedigno. Das várias técnicas de punção e biópsia, o método transbrônquico tornou-se uma rotina em diversos centros, sendo contudo a sua sensibilidade variável (técnica cega.Os autores descrevem um novo método de diagnóstico de lesões sólidas, incluindo gânglios mediastínicos e hilares através de ecografia endoscópica transbrônquica com biópsia aspirativa guiada em tempo real.Onze doentes com idade média de 58 anos foram submetidos a esta técnica: 3 com o diagnóstico de cancro do pulmão e suspeita de metástases ganglionares mediastínicas; 4 com suspeita de recorrência de tumor com metástases ganglionares; 3 com metástases ganglionares mediastínicas e hilares de etiologia desconhecida e um com suspeita de metastização ganglionar de cancro da mama. Todos os doentes tinham previamente efectuado broncofibroscopia que foi inconclusiva.O broncofibroscópio (BFC ecográfico utilizado foi um protótipo criado pela Olympus, com uma sonda endoscópica na extremidade distal e com um grau de penetração em profundidade de 5 cm e um ângulo de varredura de 50º. Os doentes realizaram o exame sob anestesia geral, com introdução do BFC através de um tubo orotraqueal.A endoscopia foi efectuada em contacto directo com a parede brônquica e, ao localizar a lesão, a agulha de aspiração era introduzida através do canal de trabalho com visualização endoscópica directa da inserção e da biópsia.Quize lesões com dimensões de 7 a 80 mm foram puncionadas, sem registo de complicações, identificandose células malignas em 13 e c

  14. Hydrogen purifier module with membrane support

    Science.gov (United States)

    A hydrogen purifier utilizing a hydrogen-permeable membrane to purify hydrogen from mixed gases containing hydrogen is disclosed. Improved mechanical support for the permeable membrane is described, enabling forward or reverse differential pressurization of the membrane, which further stabilizes the membrane from wrinkling upon hydrogen uptake.

    2012-07-24

    A hydrogen purifier utilizing a hydrogen-permeable membrane to purify hydrogen from mixed gases containing hydrogen is disclosed. Improved mechanical support for the permeable membrane is described, enabling forward or reverse differential pressurization of the membrane, which further stabilizes the membrane from wrinkling upon hydrogen uptake.

  15. The Norwegian hydrogen guide 2010

    Energy Technology Data Exchange (ETDEWEB)

    2010-07-01

    Hydrogen technologies are maturing at rapid speed, something we experience in Norway and around the globe every day as demonstration projects for vehicles and infrastructure expand at a rate unthinkable of only a few years ago. An example of this evolution happened in Norway in 2009 when two hydrogen filling stations were opened on May the 11th, making it possible to arrange the highly successful Viking Rally from Oslo to Stavanger with more than 40 competing teams. The Viking Rally demonstrated for the public that battery and hydrogen-electric vehicles are technologies that exist today and provide a real alternative for zero emission mobility in the future. The driving range of the generation of vehicles put into demonstration today is more than 450 km on a full hydrogen tank, comparable to conventional vehicles. As the car industry develops the next generation of vehicles for serial production within the next 4-5 years, we will see vehicles that are more robust, more reliable and cost effective. Also on the hydrogen production and distribution side progress is being made, and since renewable hydrogen from biomass and electrolysis is capable of making mobility basically emission free, hydrogen can be a key component in combating climate change and reducing local emissions. The research Council of Norway has for many years supported the development of hydrogen and fuel cell technologies, and The Research Council firmly believes that hydrogen and fuel cell technologies play a crucial role in the energy system of the future. Hydrogen is a flexible transportation fuel, and offers possibilities for storing and balancing intermittent electricity in the energy system. Norwegian companies, research organisations and universities have during the last decade developed strong capabilities in hydrogen and fuel cell technologies, capabilities it is important to further develop so that Norwegian actors can supply high class hydrogen and fuel cell technologies to global markets

  16. Hydrogen and OUr Energy Future

    Energy Technology Data Exchange (ETDEWEB)

    Rick Tidball; Stu Knoke

    2009-03-01

    In 2003, President George W. Bush announced the Hydrogen Fuel Initiative to accelerate the research and development of hydrogen, fuel cell, and infrastructure technologies that would enable hydrogen fuel cell vehicles to reach the commercial market in the 2020 timeframe. The widespread use of hydrogen can reduce our dependence on imported oil and benefit the environment by reducing greenhouse gas emissions and criteria pollutant emissions that affect our air quality. The Energy Policy Act of 2005, passed by Congress and signed into law by President Bush on August 8, 2005, reinforces Federal government support for hydrogen and fuel cell technologies. Title VIII, also called the 'Spark M. Matsunaga Hydrogen Act of 2005' authorizes more than $3.2 billion for hydrogen and fuel cell activities intended to enable the commercial introduction of hydrogen fuel cell vehicles by 2020, consistent with the Hydrogen Fuel Initiative. Numerous other titles in the Act call for related tax and market incentives, new studies, collaboration with alternative fuels and renewable energy programs, and broadened demonstrations--clearly demonstrating the strong support among members of Congress for the development and use of hydrogen fuel cell technologies. In 2006, the President announced the Advanced Energy Initiative (AEI) to accelerate research on technologies with the potential to reduce near-term oil use in the transportation sector--batteries for hybrid vehicles and cellulosic ethanol--and advance activities under the Hydrogen Fuel Initiative. The AEI also supports research to reduce the cost of electricity production technologies in the stationary sector such as clean coal, nuclear energy, solar photovoltaics, and wind energy.

  17. O uso da biópsia aspirativa com agulha fina (BAAF no diagnóstico de lesão iriana suspeita: relato de caso Fine needle aspiration biopsy (FNAB in the diagnosis of a suspicious iris lesion: case report

    Directory of Open Access Journals (Sweden)

    Zélia Maria da Silva Corrêa

    2001-08-01

    Full Text Available Relatar o caso de um paciente que apresentou massa intra-ocular sólida no segmento anterior do olho direito e a investigação diagnóstica escolhida pelos autores. A dúvida diagnóstica e a recusa do paciente em aceitar o tratamento levaram os autores a realizar uma biópsia aspirativa com agulha fina da lesão. A biópsia foi realizada por meio de punção por via corneana, através do humor aquoso até a lesão tumoral. A citologia do material coletado na biópsia determinou a estratégia terapêutica neste caso. O diagnóstico citológico foi melanoma maligno primário da coróide do tipo misto. Sugeriu-se a enucleação do globo ocular devido à localização do tumor e seu potencial para metástases à distância. Após a enucleação, o exame anatomopatológico apresentou resultado concordante com a citologia. O paciente está sendo acompanhado clinicamente, sem sinais de metástases 2 anos após enucleação.To report the case of a patient who presented with a solid anterior segment intraocular mass in his right eye, and the diagnostic investigation chosen by the authors. Diagnostic uncertainty and patient's refusal to agree with the treatment caused the authors to perform a fine needle aspiration biopsy of the lesion. Biopsy was performed by corneal puncture, through the aqueous and the tumor. Cytology of the specimen obtained by the biopsy determined the therapeutic strategy for this case. Cytology diagnosis was consistent with primary malignant melanoma of the choroid of mixed cell type. Enucleation of the eye was suggested due to the position of the tumor and its potential to spread distant metastases. After enucleation, anatomopathological examination of the eye presented a similar result to cytology. The patient is currently been followed, with no signs of metastasis 2 years after enucleation.

  18. Distance criterion for hydrogen bond

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Distance criterion for hydrogen bond. In a D-H ...A contact, the D...A distance must be less than the sum of van der Waals Radii of the D and A atoms, for it to be a hydrogen bond.

  19. Hydrogen production through biocatalyzed electrolysis

    NARCIS (Netherlands)

    Rozendal, R.A.

    2007-01-01

    cum laude graduation (with distinction) To replace fossil fuels, society is currently considering alternative clean fuels for transportation. Hydrogen could be such a fuel. In theory, large amounts of renewable hydrogen can be produced from organic contaminants in wastewater. During his PhD research

  20. Hydrogen Technology Education Workshop Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    None

    2002-12-01

    This document outlines activities for educating key target audiences, as suggested by workshop participants. Held December 4-5, 2002, the Hydrogen Technology Education Workshop kicked off a new education effort coordinated by the Hydrogen, Fuel Cells, & Infrastructure Technologies Program of the Office of Energy Efficiency and Renewable Energy.

  1. Hydrogen effects in corrosion: discussion

    Science.gov (United States)

    Stopher, Miles A.; Simpson, E. Luke

    2017-06-01

    This session contained talks on the characterization of hydrogen-enhanced corrosion of steels and nickel-based alloys, emphasizing the different observations across length scales, from atomic-scale spectrographic to macro-scale fractographic examinations. This article is part of the themed issue 'The challenges of hydrogen and metals'.

  2. Hydrogen Production by Thermophilic Fermentation

    NARCIS (Netherlands)

    Niel, van E.W.J.; Willquist, K.; Zeidan, A.A.; Vrije, de T.; Mars, A.E.; Claassen, P.A.M.

    2012-01-01

    Of the many ways hydrogen can be produced, this chapter focuses on biological hydrogen production by thermophilic bacteria and archaea in dark fermentations. The thermophiles are held as promising candidates for a cost-effective fermentation process, because of their relatively high yields and broad

  3. Hydrogen manufacturing using plasma reformers

    Energy Technology Data Exchange (ETDEWEB)

    Bromberg, L.; Cohn, D.R.; Rabinovich, A.; Hochgreb, S.; O`Brien, C. [Massachusetts Institute of Technology, Cambridge, MA (United States)

    1996-10-01

    Manufacturing of hydrogen from hydrocarbon fuels is needed for a variety of applications. These applications include fuel cells used in stationary electric power production and in vehicular propulsion. Hydrogen can also be used for various combustion engine systems. There is a wide range of requirements on the capacity of the hydrogen manufacturing system, the purity of the hydrogen fuel, and capability for rapid response. The overall objectives of a hydrogen manufacturing facility are to operate with high availability at the lowest possible cost and to have minimal adverse environmental impact. Plasma technology has potential to significantly alleviate shortcomings of conventional means of manufacturing hydrogen. These shortcomings include cost and deterioration of catalysts; limitations on hydrogen production from heavy hydrocarbons; limitations on rapid response; and size and weight requirements. In addition, use of plasma technology could provide for a greater variety of operating modes; in particular the possibility of virtual elimination of CO{sub 2} production by pyrolytic operation. This mode of hydrogen production may be of increasing importance due to recent additional evidence of global warming.

  4. HYDROGEN VACANCY INTERACTION IN TUNGSTEN

    NARCIS (Netherlands)

    FRANSENS, [No Value; ELKERIEM, MSA; PLEITER, F

    1991-01-01

    Hydrogen-vacancy interaction in tungsten was investigated by means of the perturbed angular correlation technique, using the isotope In-111 as a probe. Hydrogen trapping at an In-111-vacancy cluster manifests itself as a change of the local electric field gradient, which gives rise to an observable

  5. Performance of Existing Hydrogen Stations

    Energy Technology Data Exchange (ETDEWEB)

    Sprik, Samuel [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kurtz, Jennifer M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Ainscough, Christopher D [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Saur, Genevieve [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Peters, Michael C [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-12-01

    In this presentation, the National Renewable Energy Laboratory presented aggregated analysis results on the performance of existing hydrogen stations, including performance, operation, utilization, maintenance, safety, hydrogen quality, and cost. The U.S. Department of Energy funds technology validation work at NREL through its National Fuel Cell Technology Evaluation Center (NFCTEC).

  6. Synchronizing Strategies under Partial Observability

    DEFF Research Database (Denmark)

    Larsen, Kim Guldstrand; Laursen, Simon; Srba, Jiri

    2014-01-01

    Embedded devices usually share only partial information about their current configurations as the communication bandwidth can be restricted. Despite this, we may wish to bring a failed device into a given predetermined configuration. This problem, also known as resetting or synchronizing words, has...... been intensively studied for systems that do not provide any information about their configurations. In order to capture more general scenarios, we extend the existing theory of synchronizing words to synchronizing strategies, and study the synchronization, short-synchronization and subset...

  7. Laparoscopic Partial Hepatectomy: Animal Experiments

    Directory of Open Access Journals (Sweden)

    Haruhiro Inoue

    1995-01-01

    Full Text Available As a first step in firmly establishing laparoscopic hepatectomy, we introduce a porcine model of laparoscopic partial hepatectomy. This procedure has been successfully performed under the normal-pressure or low-pressure pneumoperitoneum condition supported by the full-thickness abdominal wall lifting technique. An ultrasonic dissector combined with electrocautery, newly developed by Olympus Optical Corporation (Japan was effectively utilized in facilitating safe and smooth incisions into the liver parenchyma. Although indications for this procedure seem to be limited only to peripheral lesions and not to central lesions, clinical application of this method may be useful for some patients in the near future.

  8. Partial differential equations an introduction

    CERN Document Server

    Colton, David

    2004-01-01

    Intended for a college senior or first-year graduate-level course in partial differential equations, this text offers students in mathematics, engineering, and the applied sciences a solid foundation for advanced studies in mathematics. Classical topics presented in a modern context include coverage of integral equations and basic scattering theory. This complete and accessible treatment includes a variety of examples of inverse problems arising from improperly posed applications. Exercises at the ends of chapters, many with answers, offer a clear progression in developing an understanding of

  9. Implementing circularity using partial evaluation

    DEFF Research Database (Denmark)

    Lawall, Julia Laetitia

    2001-01-01

    of an imperative C-like language, by extending the language with a new construct, persistent variables. We show that an extension of partial evaluation can eliminate persistent variables, producing a staged C program. This approach has been implemented in the Tempo specializer for C programs, and has proven useful......Complex data dependencies can often be expressed concisely by defining a variable in terms of part of its own value. Such a circular reference can be naturally expressed in a lazy functional language or in an attribute grammar. In this paper, we consider circular references in the context...

  10. Partial coalescence of soap bubbles

    Science.gov (United States)

    Harris, Daniel M.; Pucci, Giuseppe; Bush, John W. M.

    2015-11-01

    We present the results of an experimental investigation of the merger of a soap bubble with a planar soap film. When gently deposited onto a horizontal film, a bubble may interact with the underlying film in such a way as to decrease in size, leaving behind a smaller daughter bubble with approximately half the radius of its progenitor. The process repeats up to three times, with each partial coalescence event occurring over a time scale comparable to the inertial-capillary time. Our results are compared to the recent numerical simulations of Martin and Blanchette and to the coalescence cascade of droplets on a fluid bath.

  11. Advanced Hydrogen Turbine Development

    Energy Technology Data Exchange (ETDEWEB)

    Marra, John [Siemens Energy, Inc., Orlando, FL (United States)

    2015-09-30

    Under the sponsorship of the U.S. Department of Energy (DOE) National Energy Technology Laboratories, Siemens has completed the Advanced Hydrogen Turbine Development Program to develop an advanced gas turbine for incorporation into future coal-based Integrated Gasification Combined Cycle (IGCC) plants. All the scheduled DOE Milestones were completed and significant technical progress was made in the development of new technologies and concepts. Advanced computer simulations and modeling, as well as subscale, full scale laboratory, rig and engine testing were utilized to evaluate and select concepts for further development. Program Requirements of: A 3 to 5 percentage point improvement in overall plant combined cycle efficiency when compared to the reference baseline plant; 20 to 30 percent reduction in overall plant capital cost when compared to the reference baseline plant; and NOx emissions of 2 PPM out of the stack. were all met. The program was completed on schedule and within the allotted budget

  12. Hydrogen in semiconductors II

    CERN Document Server

    Nickel, Norbert H; Weber, Eicke R; Nickel, Norbert H

    1999-01-01

    Since its inception in 1966, the series of numbered volumes known as Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. The "Willardson and Beer" Series, as it is widely known, has succeeded in publishing numerous landmark volumes and chapters. Not only did many of these volumes make an impact at the time of their publication, but they continue to be well-cited years after their original release. Recently, Professor Eicke R. Weber of the University of California at Berkeley joined as a co-editor of the series. Professor Weber, a well-known expert in the field of semiconductor materials, will further contribute to continuing the series' tradition of publishing timely, highly relevant, and long-impacting volumes. Some of the recent volumes, such as Hydrogen in Semiconductors, Imperfections in III/V Materials, Epitaxial Microstructures, High-Speed Heterostructure Devices, Oxygen in Silicon, and others promise that this tradition ...

  13. Metallization of fluid hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Nellis, W.J.; Louis, A.A.; Ashcroft, N.W.

    1997-05-14

    The electrical activity of liquid hydrogen has been measured at the high dynamic pressures, and temperatures that can be achieved with a reverberating shock wave. The resulting data are most naturally interpreted in terms of a continuous transition from a semiconducting to a metallic, largely diatomic fluid, the latter at 140 CPa, (ninefold compression) and 3000 K. While the fluid at these conditions resembles common liquid metals by the scale of its resistivity of 500 micro-ohm-cm, it differs by retaining a strong pairing character, and the precise mechanism by which a metallic state might be attained is still a matter of debate. Some evident possibilities include (i) physics of a largely one-body character, such as a band-overlap transition, (ii) physics of a strong-coupling or many-body character,such as a Mott-Hubbard transition, and (iii) process in which structural changes are paramount.

  14. Sampling the Hydrogen Atom

    Directory of Open Access Journals (Sweden)

    Graves N.

    2013-01-01

    Full Text Available A model is proposed for the hydrogen atom in which the electron is an objectively real particle orbiting at very near to light speed. The model is based on the postulate that certain velocity terms associated with orbiting bodies can be considered as being af- fected by relativity. This leads to a model for the atom in which the stable electron orbits are associated with orbital velocities where Gamma is n /α , leading to the idea that it is Gamma that is quantized and not angular momentum as in the Bohr and other models. The model provides a mechanism which leads to quantization of energy levels within the atom and also provides a simple mechanical explanation for the Fine Struc- ture Constant. The mechanism is closely associated with the Sampling theorem and the related phenomenon of aliasing developed in the mid-20th century by engineers at Bell labs.

  15. Magnetic refrigerator for hydrogen liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, K; Kondo, T [Department of Physics, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan); Yoshioka, S; Kamiya, K; Numazawa, T [Tsukuba Magnet Laboratory, National Institute for Materials Science, 3-13 Sakura, Tsukuba 305-0003 (Japan)], E-mail: kmatsu@kenroku.kanazawa-u.ac.jp

    2009-02-01

    Magnetic refrigeration which is based on the magnetocaloric effect of solids has the potential to achieve high thermal efficiency for hydrogen liquefaction. We have been developing a magnetic refrigerator for hydrogen liquefaction which cools down hydrogen gas from liquid natural gas temperature and liquefies at 20 K. The magnetic liquefaction system consists of two magnetic refrigerators: Carnot magnetic refrigerator (CMR) and active magnetic regenerator (AMR) device. CMR with Carnot cycle succeeded in liquefying hydrogen at 20K. Above liquefaction temperature, a regenerative refrigeration cycle should be necessary to precool hydrogen gas, because adiabatic temperature change of magnetic material is reduced due to a large lattice specific heat of magnetic materials. We have tested an AMR device as the precooling stage. It was confirmed for the first time that AMR cycle worked around 20 K.

  16. Hydrogen production from solar energy

    Science.gov (United States)

    Eisenstadt, M. M.; Cox, K. E.

    1975-01-01

    Three alternatives for hydrogen production from solar energy have been analyzed on both efficiency and economic grounds. The analysis shows that the alternative using solar energy followed by thermochemical decomposition of water to produce hydrogen is the optimum one. The other schemes considered were the direct conversion of solar energy to electricity by silicon cells and water electrolysis, and the use of solar energy to power a vapor cycle followed by electrical generation and electrolysis. The capital cost of hydrogen via the thermochemical alternative was estimated at $575/kW of hydrogen output or $3.15/million Btu. Although this cost appears high when compared with hydrogen from other primary energy sources or from fossil fuel, environmental and social costs which favor solar energy may prove this scheme feasible in the future.

  17. High capacity hydrogen storage nanocomposite materials

    Energy Technology Data Exchange (ETDEWEB)

    Zidan, Ragaiy; Wellons, Matthew S.

    2017-12-12

    A novel hydrogen absorption material is provided comprising a mixture of a lithium hydride with a fullerene. The subsequent reaction product provides for a hydrogen storage material which reversibly stores and releases hydrogen at temperatures of about 270.degree. C.

  18. Storage of liquid hydrogen in natural zeolite

    National Research Council Canada - National Science Library

    Pavol Rybár; Carsten Drebenstedt; Mário Molokáč; Ladislav Hvizdák; Ľubomír Štrba

    2015-01-01

    .... Therefore, the storage of hydrogen is relatively dangerous. A storage of liquid hydrogen in the natural zeolite, which is placed in large capacity battery, appears to be a suitable hydrogen storage method...

  19. High capacity hydrogen storage nanocomposite materials

    Science.gov (United States)

    Zidan, Ragaiy; Wellons, Matthew S

    2015-02-03

    A novel hydrogen absorption material is provided comprising a mixture of a lithium hydride with a fullerene. The subsequent reaction product provides for a hydrogen storage material which reversibly stores and releases hydrogen at temperatures of about 270.degree. C.

  20. Hydrogen sulfide intoxication.

    Science.gov (United States)

    Guidotti, Tee L

    2015-01-01

    Hydrogen sulfide (H2S) is a hazard primarily in the oil and gas industry, agriculture, sewage and animal waste handling, construction (asphalt operations and disturbing marshy terrain), and other settings where organic material decomposes under reducing conditions, and in geothermal operations. It is an insoluble gas, heavier than air, with a very low odor threshold and high toxicity, driven by concentration more than duration of exposure. Toxicity presents in a unique, reliable, and characteristic toxidrome consisting, in ascending order of exposure, of mucosal irritation, especially of the eye ("gas eye"), olfactory paralysis (not to be confused with olfactory fatigue), sudden but reversible loss of consciousness ("knockdown"), pulmonary edema (with an unusually favorable prognosis), and death (probably with apnea contributing). The risk of chronic neurcognitive changes is controversial, with the best evidence at high exposure levels and after knockdowns, which are frequently accompanied by head injury or oxygen deprivation. Treatment cannot be initiated promptly in the prehospital phase, and currently rests primarily on supportive care, hyperbaric oxygen, and nitrite administration. The mechanism of action for sublethal neurotoxicity and knockdown is clearly not inhibition of cytochrome oxidase c, as generally assumed, although this may play a role in overwhelming exposures. High levels of endogenous sulfide are found in the brain, presumably relating to the function of hydrogen sulfide as a gaseous neurotransmitter and immunomodulator. Prevention requires control of exposure and rigorous training to stop doomed rescue attempts attempted without self-contained breathing apparatus, especially in confined spaces, and in sudden release in the oil and gas sector, which result in multiple avoidable deaths. © 2015 Elsevier B.V. All rights reserved.

  1. Advanced Hydrogen Turbine Development

    Energy Technology Data Exchange (ETDEWEB)

    Joesph Fadok

    2008-01-01

    Siemens has developed a roadmap to achieve the DOE goals for efficiency, cost reduction, and emissions through innovative approaches and novel technologies which build upon worldwide IGCC operational experience, platform technology, and extensive experience in G-class operating conditions. In Phase 1, the technologies and concepts necessary to achieve the program goals were identified for the gas turbine components and supporting technology areas and testing plans were developed to mitigate identified risks. Multiple studies were conducted to evaluate the impact in plant performance of different gas turbine and plant technologies. 2015 gas turbine technologies showed a significant improvement in IGCC plant efficiency, however, a severe performance penalty was calculated for high carbon capture cases. Thermodynamic calculations showed that the DOE 2010 and 2015 efficiency targets can be met with a two step approach. A risk management process was instituted in Phase 1 to identify risk and develop mitigation plans. For the risks identified, testing and development programs are in place and the risks will be revisited periodically to determine if changes to the plan are necessary. A compressor performance prediction has shown that the design of the compressor for the engine can be achieved with additional stages added to the rear of the compressor. Tip clearance effects were studied as well as a range of flow and pressure ratios to evaluate the impacts to both performance and stability. Considerable data was obtained on the four candidate combustion systems: diffusion, catalytic, premix, and distributed combustion. Based on the results of Phase 1, the premixed combustion system and the distributed combustion system were chosen as having the most potential and will be the focus of Phase 2 of the program. Significant progress was also made in obtaining combustion kinetics data for high hydrogen fuels. The Phase 1 turbine studies indicate initial feasibility of the

  2. Liquid hydrogen: back to basics

    Energy Technology Data Exchange (ETDEWEB)

    Sherif, S.A. [Dept. of Mechanical and Aerospace Engineering, Univ. of Florida, Florida (United States)

    2009-07-01

    'Full text': Liquid hydrogen is primarily used as a rocket fuel and is predestined for supersonic and hypersonic space vehicles to a large extent because it has the lowest boiling point density and the highest specific thrust of any known fuel. Its favorable characteristics include its high heating value per unit mass, its wide ignition range in hydrogen/oxygen or air mixtures, as well as its large flame speed and cooling capacity due to its high specific heat which permits very effective engine cooling and cooling the critical parts of the outer skin. Liquid hydrogen has some other important uses such as in high-energy nuclear physics and bubble chambers. The transport of hydrogen is vastly more economical when it is in liquid form even though cryogenic refrigeration and special Dewar vessels are required. Although liquid hydrogen can provide a lot of advantages, its uses are restricted in part because liquefying hydrogen by existing conventional methods consumes a large amount of energy (around 30% of its heating value). Liquefying 1 kg of hydrogen in a medium-size plant requires 10 to 13 kWh of electric energy. In addition, boil-off losses associated with the storage, transportation, and handling of liquid hydrogen can consume up to 40% of its available combustion energy. It is therefore important to search for ways that can improve the efficiency of the liquefiers and diminish the boil-off losses. This lecture gives an overview of the main issues associated with the production, storage, and handling of liquid hydrogen. Some discussion of promising ways of hydrogen liquefaction will also be presented. (author)

  3. Complex partial seizures: cerebellar metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Theodore, W.H.; Fishbein, D.; Deitz, M.; Baldwin, P.

    1987-07-01

    We used positron emission tomography (PET) with (/sup 18/F)2-deoxyglucose to study cerebellar glucose metabolism (LCMRglu) and the effect of phenytoin (PHT) in 42 patients with complex partial seizures (CPS), and 12 normal controls. Mean +/- SD patient LCMRglu was 6.9 +/- 1.8 mg glucose/100 g/min (left = right), significantly lower than control values of 8.5 +/- 1.8 (left, p less than 0.006), and 8.3 +/- 1.6 (right, p less than 0.02). Only four patients had cerebellar atrophy on CT/MRI; cerebellar LCMRglu in these was 5.5 +/- 1.5 (p = 0.054 vs. total patient sample). Patients with unilateral temporal hypometabolism or EEG foci did not have lateralized cerebellar hypometabolism. Patients receiving phenytoin (PHT) at the time of scan and patients with less than 5 years total PHT exposure had lower LCMRglu, but the differences were not significant. There were weak inverse correlations between PHT level and cerebellar LCMRglu in patients receiving PHT (r = -0.36; 0.05 less than p less than 0.1), as well as between length of illness and LCMRglu (r = -0.22; 0.05 less than p less than 0.1). Patients with complex partial seizures have cerebellar hypometabolism that is bilateral and due only in part to the effect of PHT.

  4. Storage of liquid hydrogen in natural zeolite

    OpenAIRE

    Pavol Rybár; Carsten Drebenstedt; Mário Molokáč; Ladislav Hvizdák; Ľubomír Štrba

    2015-01-01

    When producing and utilizing hydrogen, its storage is one of the biggest problems. Hydrogen, as a gas, is extremely fluid with very low specific weight. Moreover, at a certain rate, the hydrogen-oxygen mixture is explosive. Therefore, the storage of hydrogen is relatively dangerous. A storage of liquid hydrogen in the natural zeolite, which is placed in large capacity battery, appears to be a suitable hydrogen storage method. Proposed and constructed pressure tank, large cap...

  5. Hydrogen bonding in ionic liquids.

    Science.gov (United States)

    Hunt, Patricia A; Ashworth, Claire R; Matthews, Richard P

    2015-03-07

    Ionic liquids (IL) and hydrogen bonding (H-bonding) are two diverse fields for which there is a developing recognition of significant overlap. Doubly ionic H-bonds occur when a H-bond forms between a cation and anion, and are a key feature of ILs. Doubly ionic H-bonds represent a wide area of H-bonding which has yet to be fully recognised, characterised or explored. H-bonds in ILs (both protic and aprotic) are bifurcated and chelating, and unlike many molecular liquids a significant variety of distinct H-bonds are formed between different types and numbers of donor and acceptor sites within a given IL. Traditional more neutral H-bonds can also be formed in functionalised ILs, adding a further level of complexity. Ab initio computed parameters; association energies, partial charges, density descriptors as encompassed by the QTAIM methodology (ρBCP), qualitative molecular orbital theory and NBO analysis provide established and robust mechanisms for understanding and interpreting traditional neutral and ionic H-bonds. In this review the applicability and extension of these parameters to describe and quantify the doubly ionic H-bond has been explored. Estimating the H-bonding energy is difficult because at a fundamental level the H-bond and ionic interaction are coupled. The NBO and QTAIM methodologies, unlike the total energy, are local descriptors and therefore can be used to directly compare neutral, ionic and doubly ionic H-bonds. The charged nature of the ions influences the ionic characteristics of the H-bond and vice versa, in addition the close association of the ions leads to enhanced orbital overlap and covalent contributions. The charge on the ions raises the energy of the Ylp and lowers the energy of the X-H σ* NBOs resulting in greater charge transfer, strengthening the H-bond. Using this range of parameters and comparing doubly ionic H-bonds to more traditional neutral and ionic H-bonds it is clear that doubly ionic H-bonds cover the full range of weak

  6. Abstract methods in partial differential equations

    CERN Document Server

    Carroll, Robert W

    2012-01-01

    Detailed, self-contained treatment examines modern abstract methods in partial differential equations, especially abstract evolution equations. Suitable for graduate students with some previous exposure to classical partial differential equations. 1969 edition.

  7. [Removable partial dentures. Oral functions and types].

    Science.gov (United States)

    Creugers, N H J; de Baat, C

    2009-11-01

    A removable partial denture enables the restoration or improvement of 4 oral functions: aesthetics, mandibular stability, mastication, and speech. However, wearing a removable partial denture should not cause oral comfort to deteriorate. There are 3 types of removable partial dentures: acrylic tissue-supported dentures, dentures with cast metal frameworks en dentures with cast metal frameworks and (semi)precision attachments. Interrupted tooth arches,free-ending tooth arches, and a combination of interrupted as well as free-ending tooth arches can be restored using these dentures. Well-known disadvantages of removable partial dentures are problematic oral hygiene, negative influence on the remaining dentition and limited oral comfort. Due to the advanced possibilities of fixed tooth- or implant-supported partial dentures, whether or not free-ending, or tooth- as well as implant-supported partial dentures, the indication of removable partial dentures is restricted. Nevertheless, for the time being the demand for removable partial dentures is expected to continue.

  8. Hydrogen storage in nanostructured materials

    Energy Technology Data Exchange (ETDEWEB)

    Assfour, Bassem

    2011-02-28

    Hydrogen is an appealing energy carrier for clean energy use. However, storage of hydrogen is still the main bottleneck for the realization of an energy economy based on hydrogen. Many materials with outstanding properties have been synthesized with the aim to store enough amount of hydrogen under ambient conditions. Such efforts need guidance from material science, which includes predictive theoretical tools. Carbon nanotubes were considered as promising candidates for hydrogen storage applications, but later on it was found to be unable to store enough amounts of hydrogen under ambient conditions. New arrangements of carbon nanotubes were constructed and hydrogen sorption properties were investigated using state-of-the-art simulation methods. The simulations indicate outstanding total hydrogen uptake (up to 19.0 wt.% at 77 K and 5.52wt.% at 300 K), which makes these materials excellent candidates for storage applications. This reopens the carbon route to superior materials for a hydrogen-based economy. Zeolite imidazolate frameworks are subclass of MOFs with an exceptional chemical and thermal stability. The hydrogen adsorption in ZIFs was investigated as a function of network geometry and organic linker exchange. Ab initio calculations performed at the MP2 level to obtain correct interaction energies between hydrogen molecules and the ZIF framework. Subsequently, GCMC simulations are carried out to obtain the hydrogen uptake of ZIFs at different thermodynamic conditions. The best of these materials (ZIF-8) is found to be able to store up to 5 wt.% at 77 K and high pressure. We expected possible improvement of hydrogen capacity of ZIFs by substituting the metal atom (Zn{sup 2+}) in the structure by lighter elements such as B or Li. Therefore, we investigated the energy landscape of LiB(IM)4 polymorphs in detail and analyzed their hydrogen storage capacities. The structure with the fau topology was shown to be one of the best materials for hydrogen storage. Its

  9. High efficiency stationary hydrogen storage

    Energy Technology Data Exchange (ETDEWEB)

    Hynek, S.; Fuller, W.; Truslow, S. [Arthur D. Little, Inc., Cambridge, MA (United States)

    1995-09-01

    Stationary storage of hydrogen permits one to make hydrogen now and use it later. With stationary hydrogen storage, one can use excess electrical generation capacity to power an electrolyzer, and store the resultant hydrogen for later use or transshipment. One can also use stationary hydrogen as a buffer at fueling stations to accommodate non-steady fueling demand, thus permitting the hydrogen supply system (e.g., methane reformer or electrolyzer) to be sized to meet the average, rather than the peak, demand. We at ADL designed, built, and tested a stationary hydrogen storage device that thermally couples a high-temperature metal hydride to a phase change material (PCM). The PCM captures and stores the heat of the hydriding reaction as its own heat of fusion (that is, it melts), and subsequently returns that heat of fusion (by freezing) to facilitate the dehydriding reaction. A key component of this stationary hydrogen storage device is the metal hydride itself. We used nickel-coated magnesium powder (NCMP) - magnesium particles coated with a thin layer of nickel by means of chemical vapor deposition (CVD). Magnesium hydride can store a higher weight fraction of hydrogen than any other practical metal hydride, and it is less expensive than any other metal hydride. We designed and constructed an experimental NCM/PCM reactor out of 310 stainless steel in the form of a shell-and-tube heat exchanger, with the tube side packed with NCMP and the shell side filled with a eutectic mixture of NaCL, KCl, and MgCl{sub 2}. Our experimental results indicate that with proper attention to limiting thermal losses, our overall efficiency will exceed 90% (DOE goal: >75%) and our overall system cost will be only 33% (DOE goal: <50%) of the value of the delivered hydrogen. It appears that NCMP can be used to purify hydrogen streams and store hydrogen at the same time. These prospects make the NCMP/PCM reactor an attractive component in a reformer-based hydrogen fueling station.

  10. PARALLEL SOLUTION METHODS OF PARTIAL DIFFERENTIAL EQUATIONS

    Directory of Open Access Journals (Sweden)

    Korhan KARABULUT

    1998-03-01

    Full Text Available Partial differential equations arise in almost all fields of science and engineering. Computer time spent in solving partial differential equations is much more than that of in any other problem class. For this reason, partial differential equations are suitable to be solved on parallel computers that offer great computation power. In this study, parallel solution to partial differential equations with Jacobi, Gauss-Siedel, SOR (Succesive OverRelaxation and SSOR (Symmetric SOR algorithms is studied.

  11. Problems in Hydrodynamics and Partial Differential Equations.

    Science.gov (United States)

    CALCULUS OF VARIATIONS, RESEARCH MANAGEMENT ), NONLINEAR DIFFERENTIAL EQUATIONS, PARTIAL DIFFERENTIAL EQUATIONS, BOUNDARY VALUE PROBLEMS, EQUATIONS, INEQUALITIES, MEASURE THEORY , INTEGRALS, ABSTRACTS

  12. Hydrogen-Based Energy Conservation System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Sustainable Innovations is developing a technology for efficient separation and compression of hydrogen gas. The electrochemical hydrogen separator and compressor...

  13. Composition and method for hydrogen storage

    Science.gov (United States)

    Mao, Wendy L. (Inventor); Mao, Ho-Kwang (Inventor)

    2004-01-01

    A method for hydrogen storage includes providing water and hydrogen gas to a containment volume, reducing the temperature of the water and hydrogen gas to form a hydrogen clathrate at a first cryogenic temperature and a first pressure and maintaining the hydrogen clathrate at second cryogenic temperature within a temperature range of up to 250 K to effect hydrogen storage. The low-pressure hydrogen hydrate includes H.sub.2 O molecules, H.sub.2 molecules and a unit cell including polyhedron cages of hydrogen-bonded frameworks of the H.sub.2 O molecules built around the H.sub.2 molecules.

  14. Pancharatnam geometric phase originating from successive partial ...

    Indian Academy of Sciences (India)

    Abstract. The spin of a polarized neutron beam subjected to a partial projection in another direction, traces a geodesic arc in the 2-sphere ray space. We delineate the geometric phase resulting from two successive partial projections on a general quantal state and derive the direction and strength of the third partial ...

  15. The Hydra-k Partial Fields

    NARCIS (Netherlands)

    R. Pendavingh; S.H.M. van Zwam (Stefan)

    2010-01-01

    htmlabstractIn the paper "Confinement of matroid representations to subsets of partial fields" (arXiv:0806.4487) we introduced the Hydra-k partial fields to study quinary matroids with inequivalent representations. The proofs of some results on these partial fields require extensive computations.

  16. Hydrogen as a fuel for fuel cell vehicles: A technical and economic comparison

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.; Steinbugler, M.; Kreutz, T. [Princeton Univ., NJ (United States). Center for Energy and Environmental Studies

    1997-12-31

    All fuel cells currently being developed for near term use in vehicles require hydrogen as a fuel. Hydrogen can be stored directly or produced onboard the vehicle by reforming methanol, ethanol or hydrocarbon fuels derived from crude oil (e.g., Diesel, gasoline or middle distillates). The vehicle design is simpler with direct hydrogen storage, but requires developing a more complex refueling infrastructure. In this paper, the authors compare three leading options for fuel storage onboard fuel cell vehicles: compressed gas hydrogen storage; onboard steam reforming of methanol; onboard partial oxidation (POX) of hydrocarbon fuels derived from crude oil. Equilibrium, kinetic and heat integrated system (ASPEN) models have been developed to estimate the performance of onboard steam reforming and POX fuel processors. These results have been incorporated into a fuel cell vehicle model, allowing us to compare the vehicle performance, fuel economy, weight, and cost for various fuel storage choices and driving cycles. A range of technical and economic parameters were considered. The infrastructure requirements are also compared for gaseous hydrogen, methanol and hydrocarbon fuels from crude oil, including the added costs of fuel production, storage, distribution and refueling stations. Considering both vehicle and infrastructure issues, the authors compare hydrogen to other fuel cell vehicle fuels. Technical and economic goals for fuel cell vehicle and hydrogen technologies are discussed. Potential roles for hydrogen in the commercialization of fuel cell vehicles are sketched.

  17. Numerical study of microstructural evolution in low alloy Cr-Mo steels during hydrogen attack

    NARCIS (Netherlands)

    Schlogl, SM; Van der Giessen, E; Moody, NR; Thompson, AW; Ricker, RE; Was, GS; Jones, RH

    2003-01-01

    Hydrogen attack is a material degradation process which involves partial dissolution of the microstructure in favor of the growth of methane filled cavities. Two numerical models are discussed to study this multi-physics process: a simple one-dimensional model and the start of a more sophisticated

  18. Spectroscopic identification of ethanol-water conformers by large-amplitude hydrogen bond librational modes

    DEFF Research Database (Denmark)

    Andersen, Jonas; Heimdal, J.; Larsen, René Wugt

    2015-01-01

    The far-infrared absorption spectra have been recorded for hydrogen-bonded complexes of water with ethanol embedded in cryogenic neon matrices at 2.8 K. The partial isotopic H/D-substitution of the ethanol subunit enabled by a dual inlet deposition procedure enables the observation and unambiguous...

  19. Computational model for carbon diffusion and methane formation in a ferritic steel during hydrogen attack

    NARCIS (Netherlands)

    Schl”gl, S.M.; van der Giessen, E.; Schlögl, S.M.

    2002-01-01

    Hydrogen attack is a material degradation process which involves partial dissolution of the microstructure in favor of the growth of methane-filled cavities. The various physical-chemical processes involved are strongly coupled. We present a numerical microstructural model for two of these

  20. Crotonaldehyde hydrogenation on Rh/TiO2 catalysts. In situ DRIFTS studies

    NARCIS (Netherlands)

    Reyes, P.; Aguirre, M. del C.; Melian Cabrera, Ignacio; Lopez Granados, M.; Fierro, J.L.G.

    2002-01-01

    The surface and catalytic properties in the vapor-phase hydrogenation of crotonaldehyde on Rh/TiO2 has been studied. It was found that a partial reduction of the support produces a surface decoration of the metal component. Thus, interfacial sites are created, which are responsible of an increase in

  1. Electrochemical Hydrogen Compressor

    Energy Technology Data Exchange (ETDEWEB)

    David P. Bloomfield; Brian S. MacKenzie

    2006-05-01

    The Electrochemical Hydrogen Compressor EHC was evaluated against DOE applications for compressing hydrogen at automobile filling stations, in future hydrogen pipelines and as a commercial replacement for conventional diaphragm hydrogen compressors. It was also evaluated as a modular replacement for the compressors used in petrochemical refineries. If the EHC can be made inexpensive, reliable and long lived then it can satisfy all these applications save pipelines where the requirements for platinum catalyst exceeds the annual world production. The research performed did not completely investigate Molybdenum as a hydrogen anode or cathode, it did show that photoetched 316 stainless steel is inadequate for an EHC. It also showed that: molybdenum bipolar plates, photochemical etching processes, and Gortex Teflon seals are too costly for a commercial EHC. The use of carbon paper in combination with a perforated thin metal electrode demonstrated adequate anode support strength, but is suspect in promoting galvanic corrosion. The nature of the corrosion mechanisms are not well understood, but locally high potentials within the unit cell package are probably involved. The program produced a design with an extraordinary high cell pitch, and a very low part count. This is one of the promising aspects of the redesigned EHC. The development and successful demonstration of the hydraulic cathode is also important. The problem of corrosion resistant metal bipolar plates is vital to the development of an inexpensive, commercial PEM fuel cell. Our research suggests that there is more to the corrosion process in fuel cells and electrochemical compressors than simple, steady state, galvanic stability. It is an important area for scientific investigation. The experiments and analysis conducted lead to several recommended future research directions. First, we need a better understanding of the corrosion mechanisms involved. The diagnosis of experimental cells with titration to

  2. Visualizing a Catalyst at Work during the Ignition of the Catalytic Partial Oxidation of Methane

    DEFF Research Database (Denmark)

    Kimmerle, Bertram; Grunwaldt, Jan-Dierk; Baiker, Alfons

    2009-01-01

    We present a spatiotemporal operando X-ray absorption study of a highly dynamic process, the ignition of the noble metal catalyzed partial oxidation of methane. Evolvement and propagation of the platinum component's structural changes are investigated with a high-speed X-ray camera, which in comb...... in combination with temperature profiling by IR-thermography and catalytic activity measurements by online mass spectrometry gives insight into the first stages of the ignition of the reaction toward hydrogen and carbon monoxide....

  3. SUPERCRITICAL WATER PARTIAL OXIDATION PHASE I - PILOT-SCALE TESTING / FEASIBILITY STUDIES FINAL REPORT

    Energy Technology Data Exchange (ETDEWEB)

    SPRITZER,M; HONG,G

    2005-01-01

    Under Cooperative Agreement No. DE-FC36-00GO10529 for the Department of Energy, General Atomics (GA) is developing Supercritical Water Partial Oxidation (SWPO) as a means of producing hydrogen from low-grade biomass and other waste feeds. The Phase I Pilot-scale Testing/Feasibility Studies have been successfully completed and the results of that effort are described in this report. The Key potential advantages of the SWPO process is the use of partial oxidation in-situ to rapidly heat the gasification medium, resulting in less char formation and improved hydrogen yield. Another major advantage is that the high-pressure, high-density aqueous environment is ideal for reaching and gasifying organics of all types. The high water content of the medium encourages formation of hydrogen and hydrogen-rich products and is especially compatible with high water content feeds such as biomass materials. The high water content of the medium is also effective for gasification of hydrogen-poor materials such as coal. A versatile pilot plant for exploring gasification in supercritical water has been established at GA's facilities in San Diego. The Phase I testing of the SWPO process with wood and ethanol mixtures demonstrated gasification efficiencies of about 90%, comparable to those found in prior laboratory-scale SCW gasification work carreid out at the University of Hawaii at Manoa (UHM) as well as other biomass gasification experience with conventional gasifiers. As in the prior work at UHM, a significant amount of the hydrogen found in the gas phase products is derived from the water/steam matrix. The studies at UHM utilized an indirectly heated gasifier with an acitvated carbon catalyst. In contrast, the GA studies utilized a directly heated gasifier without catalyst, plus a surrogate waste fuel. Attainment of comparable gasification efficiencies without catalysis is an important advancement for the GA process, and opens the way for efficient hydrogen production from low

  4. Production of hydrogen by thermocatalytic cracking of natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Muradov, N. [Florida Solar Energy Center, Cocoa, FL (United States)

    1996-10-01

    The conventional methods of hydrogen production from natural gas (for example, steam reforming and partial oxidation) are complex, multi-step processes that produce large quantities of CO{sub 2}. The main goal of this project is to develop a technologically simple process for hydrogen production from natural gas (NG) and other hydrocarbon fuels via single-step decomposition of hydrocarbons. This approach eliminates or significantly reduces CO{sub 2} emission. Carbon is a valuable by-product of this process, whereas conventional methods of hydrogen production from NG produce no useful by-products. This approach is based on the use of special catalysts that reduce the maximum temperature of the process from 1400-1500{degrees}C (thermal non-catalytic decomposition of methane) to 500-900{degrees}C. Transition metal based catalysts and various forms of carbon are among the candidate catalysts for the process. This approach can advantageously be used for the development of compact NG reformers for on-site production of hydrogen-methane blends at refueling stations and, also, for the production of hydrogen-rich gas for fuel cell applications. The author extended the search for active methane decomposition catalysts to various modifications of Ni-, Fe-, Mo- and Co-based catalysts. Variation in the operational parameters makes it possible to produce H{sub 2}-CH{sub 4} blends with a wide range of hydrogen concentrations that vary from 15 to 98% by volume. The author found that Ni-based catalysts are more effective at temperatures below 750{degrees}C, whereas Fe-based catalysts are effective at temperatures above 800{degrees}C for the production of hydrogen with purity of 95% v. or higher. The catalytic pyrolysis of liquid hydrocarbons (pentane, gasoline) over Fe-based catalyst was conducted. The author observed the production of a hydrogen-rich gas (hydrogen concentration up to 97% by volume) at a rate of approximately 1L/min.mL of hydrocarbon fuel.

  5. Hydrogen-storing hydride complexes

    Science.gov (United States)

    Srinivasan, Sesha S [Tampa, FL; Niemann, Michael U [Venice, FL; Goswami, D Yogi [Tampa, FL; Stefanakos, Elias K [Tampa, FL

    2012-04-10

    A ternary hydrogen storage system having a constant stoichiometric molar ratio of LiNH.sub.2:MgH.sub.2:LiBH.sub.4 of 2:1:1. It was found that the incorporation of MgH.sub.2 particles of approximately 10 nm to 20 nm exhibit a lower initial hydrogen release temperature of 150.degree. C. Furthermore, it is observed that the particle size of LiBNH quaternary hydride has a significant effect on the hydrogen sorption concentration with an optimum size of 28 nm. The as-synthesized hydrides exhibit two main hydrogen release temperatures, one around 160.degree. C. and the other around 300.degree. C., with the main hydrogen release temperature reduced from 310.degree. C. to 270.degree. C., while hydrogen is first reversibly released at temperatures as low as 150.degree. C. with a total hydrogen capacity of 6 wt. % to 8 wt. %. Detailed thermal, capacity, structural and microstructural properties have been demonstrated and correlated with the activation energies of these materials.

  6. Technical Analysis of Hydrogen Production

    Energy Technology Data Exchange (ETDEWEB)

    Ali T-Raissi

    2005-01-14

    The aim of this work was to assess issues of cost, and performance associated with the production and storage of hydrogen via following three feedstocks: sub-quality natural gas (SQNG), ammonia (NH{sub 3}), and water. Three technology areas were considered: (1) Hydrogen production utilizing SQNG resources, (2) Hydrogen storage in ammonia and amine-borane complexes for fuel cell applications, and (3) Hydrogen from solar thermochemical cycles for splitting water. This report summarizes our findings with the following objectives: Technoeconomic analysis of the feasibility of the technology areas 1-3; Evaluation of the hydrogen production cost by technology areas 1; and Feasibility of ammonia and/or amine-borane complexes (technology areas 2) as a means of hydrogen storage on-board fuel cell powered vehicles. For each technology area, we reviewed the open literature with respect to the following criteria: process efficiency, cost, safety, and ease of implementation and impact of the latest materials innovations, if any. We employed various process analysis platforms including FactSage chemical equilibrium software and Aspen Technologies AspenPlus and HYSYS chemical process simulation programs for determining the performance of the prospective hydrogen production processes.

  7. Nanoporous polymers for hydrogen storage.

    Science.gov (United States)

    Germain, Jonathan; Fréchet, Jean M J; Svec, Frantisek

    2009-05-01

    The design of hydrogen storage materials is one of the principal challenges that must be met before the development of a hydrogen economy. While hydrogen has a large specific energy, its volumetric energy density is so low as to require development of materials that can store and release it when needed. While much of the research on hydrogen storage focuses on metal hydrides, these materials are currently limited by slow kinetics and energy inefficiency. Nanostructured materials with high surface areas are actively being developed as another option. These materials avoid some of the kinetic and thermodynamic drawbacks of metal hydrides and other reactive methods of storing hydrogen. In this work, progress towards hydrogen storage with nanoporous materials in general and porous organic polymers in particular is critically reviewed. Mechanisms of formation for crosslinked polymers, hypercrosslinked polymers, polymers of intrinsic microporosity, and covalent organic frameworks are discussed. Strategies for controlling hydrogen storage capacity and adsorption enthalpy via manipulation of surface area, pore size, and pore volume are discussed in detail.

  8. Solar hydrogen for urban trucks

    Energy Technology Data Exchange (ETDEWEB)

    Provenzano, J.: Scott, P.B.; Zweig, R. [Clean Air Now, Northridge, CA (United States)

    1997-12-31

    The Clean Air Now (CAN) Solar Hydrogen Project, located at Xerox Corp., El Segundo, California, includes solar photovoltaic powered hydrogen generation, compression, storage and end use. Three modified Ford Ranger trucks use the hydrogen fuel. The stand-alone electrolyzer and hydrogen dispensing system are solely powered by a photovoltaic array. A variable frequency DC-AC converter steps up the voltage to drive the 15 horsepower compressor motor. On site storage is available for up to 14,000 standard cubic feet (SCF) of solar hydrogen, and up to 80,000 SCF of commercial hydrogen. The project is 3 miles from Los Angeles International airport. The engine conversions are bored to 2.9 liter displacement and are supercharged. Performance is similar to that of the Ranger gasoline powered truck. Fuel is stored in carbon composite tanks (just behind the driver`s cab) at pressures up to 3600 psi. Truck range is 144 miles, given 3600 psi of hydrogen. The engine operates in lean burn mode, with nil CO and HC emissions. NO{sub x} emissions vary with load and rpm in the range from 10 to 100 ppm, yielding total emissions at a small fraction of the ULEV standard. Two trucks have been converted for the Xerox fleet, and one for the City of West Hollywood. A public outreach program, done in conjunction with the local public schools and the Department of Energy, introduces the local public to the advantages of hydrogen fuel technologies. The Clean Air Now program demonstrates that hydrogen powered fleet development is an appropriate, safe, and effective strategy for improvement of urban air quality, energy security and avoidance of global warming impact. Continued technology development and cost reduction promises to make such implementation market competitive.

  9. Partially coherent lensfree tomographic microscopy⋄

    Science.gov (United States)

    Isikman, Serhan O.; Bishara, Waheb; Ozcan, Aydogan

    2012-01-01

    Optical sectioning of biological specimens provides detailed volumetric information regarding their internal structure. To provide a complementary approach to existing three-dimensional (3D) microscopy modalities, we have recently demonstrated lensfree optical tomography that offers high-throughput imaging within a compact and simple platform. In this approach, in-line holograms of objects at different angles of partially coherent illumination are recorded using a digital sensor-array, which enables computing pixel super-resolved tomographic images of the specimen. This imaging modality, which forms the focus of this review, offers micrometer-scale 3D resolution over large imaging volumes of, for example, 10–15 mm3, and can be assembled in light weight and compact architectures. Therefore, lensfree optical tomography might be particularly useful for lab-on-a-chip applications as well as for microscopy needs in resource-limited settings. PMID:22193016

  10. Partial Return Yoke for MICE

    Energy Technology Data Exchange (ETDEWEB)

    Witte H.; Plate, S

    2013-05-03

    The international Muon Ionization Cooling Experiment (MICE) is a large scale experiment which is presently assembled at the Rutherford Appleton Laboratory in Didcot, UK. The purpose of MICE is to demonstrate the concept of ionization cooling experimentally. Ionization cooling is an important accelerator concept which will be essential for future HEP experiments such as a potential Muon Collider or a Neutrino Factory. The MICE experiment will house up to 18 superconducting solenoids, all of which produce a substantial amount of magnetic flux. Recently it was realized that this magnetic flux leads to a considerable stray magnetic field in the MICE hall. This is a concern as technical equipment in the MICE hall may may be compromised by this. In July 2012 a concept called partial return yoke was presented to the MICE community, which reduces the stray field in the MICE hall to a safe level. This report summarizes the general concept, engineering considerations and the expected shielding performance.

  11. Technoeconomic analysis of different options for the production of hydrogen from sunlight, wind, and biomass

    Energy Technology Data Exchange (ETDEWEB)

    Mann, M.K.; Spath, P.L.; Amos, W.A. [National Renewable Energy Lab., Golden, CO (United States)

    1998-08-01

    To determine their technical and economic viability and to provide insight into where each technology is in its development cycle, different options to produce hydrogen from sunlight, wind, and biomass were studied. Additionally, costs for storing and transporting hydrogen were determined for different hydrogen quantities and storage times. The analysis of hydrogen from sunlight examined the selling price of hydrogen from two technologies: direct photoelectrochemical (PEC) conversion of sunlight and photovoltaic (PV)-generated electricity production followed by electrolysis. The wind analysis was based on wind-generated electricity production followed by electrolysis. In addition to the base case analyses, which assume that hydrogen is the sole product, three alternative scenarios explore the economic impact of integrating the PV- and wind-based systems with the electric utility grid. Results show that PEC hydrogen production has the potential to be economically feasible. Additionally, the economics of the PV and wind electrolysis systems are improved by interaction with the grid. The analysis of hydrogen from biomass focused on three gasification technologies. The systems are: low pressure, indirectly-heated gasification followed by steam reforming; high pressure, oxygen-blown gasification followed by steam reforming; and pyrolysis followed by partial oxidation. For each of the systems studied, the downstream process steps include shift conversion followed by hydrogen purification. Only the low pressure system produces hydrogen within the range of the current industry selling prices (typically $0.7--$2/kg, or $5--14/GJ on a HHV basis). A sensitivity analysis showed that, for the other two systems, in order to bring the hydrogen selling price down to $2/kg, negative-priced feedstocks would be required.

  12. Hydrogenation of zirconium film by implantation of hydrogen ions

    Science.gov (United States)

    Liu, Yang; Fang, Kaihong; Lv, Huiyi; Liu, Jiwei; Wang, Boyu

    2017-03-01

    In order to understand the drive-in target in a D-D type neutron generator, it is essential to study the mechanism of the interaction between hydrogen ion beams and the hydrogen-absorbing metal film. The present research concerns the nucleation of hydride within zirconium film implanted with hydrogen ions. Doses of 30 keV hydrogen ions ranging from 4.30 × 1017 to 1.43 × 1018 ions cm-2 were loaded into the zirconium film through the ion beam implantation technique. Features of the surface morphology and transformation of phase structures were investigated with scanning electron microscopy, atomic force microscopy and x-ray diffraction. Confirmation of the formation of δ phase zirconium hydride in the implanted samples was first made by x-ray diffraction, and the different stages in the gradual nucleation and growth of zirconium hydride were then observed by atomic force microscope and scanning electron microscopy.

  13. Neutral Atom Diffusion in a Partially Ionized Prominence Plasma

    Science.gov (United States)

    Gilbert, Holly

    2010-01-01

    The support of solar prominences is normally described in terms of a magnetic force on the prominence plasma that balances the solar gravitational force. Because the prominence plasma is only partially ionized. it is necessary to consider in addition the support of the neutral component of the prominence plasma. This support is accomplished through a frictional interaction between the neutral and ionized components of the plasma, and its efficacy depends strongly on the degree of ionization of the plasma. More specifically, the frictional force is proportional to the relative flow of neutral and ion species, and for a sufficiently weakly ionized plasma, this flow must be relatively large to produce a frictional force that balances gravity. A large relative flow, of course, implies significant draining of neutral particles from the prominence. We evaluate the importance of this draining effect for a hydrogen-helium plasma, and consider the observational evidence for cross-field diffusion of neutral prominence material,

  14. 4-Chloroanilinium hydrogen oxalate hemihydrate

    Directory of Open Access Journals (Sweden)

    Hajer Rahmouni

    2010-04-01

    Full Text Available In the title hydrated molecular salt, C6H7ClN+·C2HO4−·0.5H2O, the water O atom lies on a crystallographic twofold axis. In the crystal, the anions are linked by O—H...O hydrogen bonds, forming chains propagating along the b axis. These chains are interconnected through O—H...O hydrogen bonds from the water molecules and N—H...O hydrogen bonds from the cations, building layers parallel to the ab plane.

  15. Fusion Energy for Hydrogen Production

    Energy Technology Data Exchange (ETDEWEB)

    Fillo, J. A.; Powell, J. R.; Steinberg, M.; Salzano, F.; Benenati, R.; Dang, V.; Fogelson, S.; Isaacs, H.; Kouts, H.; Kushner, M.; Lazareth, O.; Majeski, S.; Makowitz, H.; Sheehan, T. V.

    1978-09-01

    The decreasing availability of fossil fuels emphasizes the need to develop systems which will produce synthetic fuel to substitute for and supplement the natural supply. An important first step in the synthesis of liquid and gaseous fuels is the production of hydrogen. Thermonuclear fusion offers an inexhaustible source of energy for the production of hydrogen from water. Depending on design, electric generation efficiencies of approximately 40 to 60% and hydrogen production efficiencies by high temperature electrolysis of approximately 50 to 70% are projected for fusion reactors using high temperature blankets.

  16. Solar powered hydrogen generating facility and hydrogen powered vehicle fleet

    Science.gov (United States)

    Provenzano, J. J.

    1995-02-01

    Clean Air Now (CAN), a non-profit corporation, acting under U.S. Department of Energy Cooperative Agreement will build a Solar Hydrogen Generating Facility at the Xerox Corp. Facility in El Segundo, CA. An integral component of this system is an electrolyzer and related equipment for compression and storage of the produced hydrogen gas. CAN has selected The Electrolyser Corporation (T.E.C) to fulfill this requirement.

  17. Topological Partial *-ALGEBRAS:. Basic Properties and Examples

    Science.gov (United States)

    Antoine, J.-P.; Bagarello, F.; Trapani, C.

    Let {A} be a partial *-algebra endowed with a topology τ that makes it into a locally convex topological vector space {A} {[ τ ]}. Then {A} is called a topological partial *-algebra if it satisfies a number of conditions, which all amount to require that the topology τ fits with the multiplier structure of {A}. Besides the obvious cases of topological quasi *-algebras and CQ*-algebras, we examine several classes of potential topological partial *-algebras, either function spaces (lattices of Lp spaces on [0, 1] or on ℝ, amalgam spaces), or partial *-algebras of operators (operators on a partial inner product space, O*-algebras).

  18. Ionization of hydrogen and hydrogenic ions by antiprotons

    Science.gov (United States)

    Schultz, D. R.; Krstić, P. S.; Reinhold, C. O.; Wells, J. C.

    1996-05-01

    Motivated by earlier theoretical studies which utilized simplified models and by a very recent experiment regarding antiproton-impact of hydrogen, we present a description (D.R. Schultz, P.S. Krstić, C.O. Reinhold, and J.C. Wells, Phys. Rev. Lett. (1996) submitted.) of ionization of hydrogen and hydrogenic ions based on very large scale numerical solutions of the time-dependent Schrödinger equation in three spatial dimensions and on analysis of the topology of the electronic eigenenergy surfaces in the plane of complex internuclear distance. It is illustrated how ionization of atomic hydrogen and hydrogenic ions by antiprotons is quite different from that for impact by positively charged particles at low energies. Most significantly, for hydrogen targets, the quasi-molecular electronic eigenenergies approach close to and ultimately merge with the continuum at small distances, leading to a plateau of the low energy ionization cross section. Work supported by US DOE Office of BES through contract No. DE-AC05-84OR21400 managed by Lockheed Martin Energy Research Corp.

  19. Manifestações de padrão tuberculóide reacional na hanseníase dimorfa: estudo histoquímico e imuno-histoquímico comparativo, em biópsias cutâneas, entre reações tipo 1 ocorridas antes e durante a poliquimioterapia Manifestations of reactional tuberculoid pattern in borderline leprosy: comparative, histochemical and immunohistochemical study, in skin biopsies, between type 1 reactions ocurred before and during multidrugtherapy

    Directory of Open Access Journals (Sweden)

    Jaison Antonio Barreto

    2005-12-01

    Full Text Available FUNDAMENTOS: Na hanseníase dimorfa é comum a ocorrência de reações tipo 1 antes, durante ou depois da poliquimioterapia (PQT. Trabalhos recentes sugerem que a reação tipo 1 seria um desequilíbrio imunológico entre citocinas pró-inflamatórias e antiinflamatórias. OBJETIVOS: Compreender melhor a fisiopatologia das reações tipo 1. MÉTODOS: Estudaram-se biópsias cutâneas de 10 indivíduos com hanseníase dimorfa-tuberculóide reacional não tratada (DTR e 10 dimorfos em reação reversa após o início da PQT (DRR, comparando-se os parâmetros morfológicos e imunológicos por meio de colorações HE e Faraco-Fite, e técnicas imuno-histoquímicas (CD4, CD8, CD20, CD79a, CD57, iNOS, IL-10, LAM e BCG. RESULTADOS: Houve, nos DRR, mais macrófagos multivacuolados, maior marcação nos macrófagos para a enzima óxido nítrico sintase induzível (iNOS e menos linfócitos T CD8+ (pBACKGROUND: Type 1 reactions are common in borderline leprosy, and can occur before, during or after multidrugtherapy (MDT. Recent papers suggest that these reactions could be a result of an imbalance between proinflammatory and anti-inflammatory citokines. OBJECTIVE: To understand better the physiopathology of type 1 reactions. METHODS: We studied skin biopsies from 10 non-treated patients with reactional borderline tuberculoid leprosy (BTR and 10 from borderline leprosy with reversal reactions after the beginning of MDT (BRR, to compare morphological and immunological parameters by routine staining (H-E and Faraco-Fite and immunohistochemical technics (CD4, CD8, CD20, CD79a, CD57, iNOS, IL-10, LAM and BCG. RESULTS: We found, in BRR group, stronger staining for iNOS into macrofages, fewer CD8+ T cells and more multivacuolated macrofages than BTR group (p<0,05. Despite the presence of viable bacilli in BTR and its absence in BRR, there weren't differences in baciloscopy and staining for mycobacterial antigens (LAM and BCG between the groups. The number of IL-10

  20. Breath Hydrogen Produced by Ingestion of Commercial Hydrogen Water and Milk

    OpenAIRE

    Shimouchi, Akito; Nose, Kazutoshi; Yamaguchi, Makoto; Ishiguro, Hiroshi; Kondo, Takaharu

    2009-01-01

    Objective: To compare how and to what extent ingestion of hydrogen water and milk increase breath hydrogen in adults.Methods: Five subjects without specific diseases, ingested distilled or hydrogen water and milk as a reference material that could increase breath hydrogen. Their end-alveolar breath hydrogen was measured.Results: Ingestion of hydrogen water rapidly increased breath hydrogen to the maximal level of approximately 40 ppm 10–15 min after ingestion and thereafter rapidly decrease...