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Letteratura scientifica selezionata sul tema "Anhydrous hydrogen"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 2 febbraio 2022

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Articoli di riviste sul tema "Anhydrous hydrogen"

Rossman, George R. "Hydrogen in “anhydrous” minerals". Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 45, n. 1-4 (gennaio 1990): 41–44. http://dx.doi.org/10.1016/0168-583x(90)90780-x.

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Ingrin, Jannick, e Henrik Skogby. "Hydrogen in nominally anhydrous upper-mantle minerals: concentration levels and implications". European Journal of Mineralogy 12, n. 3 (31 maggio 2000): 543–70. http://dx.doi.org/10.1127/ejm/12/3/0543.

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Hamadène, M., H. Kherfi e A. Guehria-Laidoudi. "The polymeric anhydrous rubidium hydrogen oxalate". Acta Crystallographica Section A Foundations of Crystallography 62, a1 (6 agosto 2006): s280. http://dx.doi.org/10.1107/s0108767306094414.

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Seijas, Luis E., Gerzon E. Delgado, Asiloé J. Mora, Andrew N. Fitch e Michela Brunelli. "On the crystal structures and hydrogen bond patterns in proline pseudopolymorphs". Powder Diffraction 25, n. 3 (settembre 2010): 235–40. http://dx.doi.org/10.1154/1.3478557.

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Amino acids often cocrystallize with water molecules, which make them pseudopolymorphs of their anhydrous forms. In this work, we discuss in detail the hydrogen bond patterns in anhydrous L-proline and DL-proline and its pseudopolymorphic forms: L-proline monohydrate and DL-proline monohydrate. For this propose, the crystal structure of L-proline anhydrous was determined from synchrotron X-ray powder diffraction data and refined using the Rietveld method. Special emphasis is given to the role played by the water molecule in the hydrogen bond network observed in the crystalline structures.

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POLING, S. "Anhydrous proton conductivity in hydrogen alkali thiogermanates". Solid State Ionics 175, n. 1-4 (novembre 2004): 581–84. http://dx.doi.org/10.1016/j.ssi.2004.03.044.

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Barraclough, C. G., J. Besida, P. G. Davies e T. A. O'Donnell. "Arsenic pentafluoride equilibria in anhydrous hydrogen fluoride". Journal of Fluorine Chemistry 38, n. 3 (marzo 1988): 405–19. http://dx.doi.org/10.1016/s0022-1139(00)81076-3.

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Markovich, Yu D., A. V. Panfilov, A. A. Zhirov, A. T. Kirsanov, L. A. Gorbach e K. A. Taraskin. "Beta-ionone synthesis using anhydrous hydrogen fluoride". Pharmaceutical Chemistry Journal 32, n. 10 (ottobre 1998): 557–59. http://dx.doi.org/10.1007/bf02465747.

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Marsden, CJ. "The Fate of CrO2F2 in Highly Acidic Media: Fluoride Loss, O-Protonation or F-Protonation?" Australian Journal of Chemistry 43, n. 12 (1990): 1991. http://dx.doi.org/10.1071/ch9901991.

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Theoretical calculations at the DZ/SCF level are reported for CrO2F2 and for three of its possible products of interaction with highly acidic anhydrous hydrogen fluoride. The molecular structure and vibrational frequencies of CrO2F2 are reproduced with reasonable accuracy. It seems unlikely that CrO2F+ is formed from CrO2F2 in anhydrous hydrogen fluoride, since that ion is structurally unstable as an isolated entity. While the thermodynamic stabilities of CrO (OH)F2+ and CrO2F(FH)+ are almost identical, comparison of calculated vibrational frequencies with the experimental results of O'Donnell and coworkers suggests that the product of interaction of CrO2F2 with anhydrous hydrogen fluoride/SbF5 is CrO2F(FH]+, rather than CrO (OH)F2+. However, the Cr-F(H) bond in CrO2F(FH)+ is so much longer than the bond to the unprotonated fluorine that CrO2F(FH)+ is perhaps best described as a CrO2F+ ion strongly solvated by one HF molecule.

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Smith, Graham, Urs D. Wermuth, David J. Young e Peter C. Healy. "Anhydrous guanidinium hydrogen fumarate: a two-dimensional hydrogen-bonded network structure". Acta Crystallographica Section E Structure Reports Online 63, n. 2 (10 gennaio 2007): o556—o557. http://dx.doi.org/10.1107/s1600536806056042.

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O'Donnell, Thomas A. "Lewis acidity and synthesis in anhydrous hydrogen fluoride". Journal of Fluorine Chemistry 29, n. 1-2 (agosto 1985): 12. http://dx.doi.org/10.1016/s0022-1139(00)83249-2.

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Più fonti

Tesi sul tema "Anhydrous hydrogen"

Johnson, Jessica Mary. "Chlorine production from anhydrous hydrogen chloride in a molten salt electrolyte membrane cell". Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/11246.

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Weis, Franz A. "Hydrogen in nominally anhydrous silicate minerals : Quantification methods, incorporation mechanisms and geological applications". Doctoral thesis, Uppsala universitet, Mineralogi, petrologi och tektonik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-306212.

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The aim of this thesis is to increase our knowledge and understanding of trace water concentrations in nominally anhydrous minerals (NAMs). Special focus is put on the de- and rehydration mechanisms of clinopyroxene crystals in volcanic systems, how these minerals can be used to investigate the volatile content of mantle rocks and melts on both Earth and other planetary bodies (e.g., Mars). Various analytical techniques for water concentration analysis were evaluated. The first part of the thesis focusses on rehydration experiments in hydrogen gas at 1 atm and under hydrothermal pressures from 0.5 to 3 kbar on volcanic clinopyroxene crystals in order to test hydrogen incorporation and loss from crystals and how their initial water content at crystallization prior to dehydration may be restored. The results show that extensive dehydration may occur during magma ascent and degassing but may be hindered by fast ascent rates with limited volatile loss. De- and rehydration processes are governed by the redox-reaction OH- + Fe2+ ↔ O2- + Fe3+ + ½ H2. Performing rehydration experiments at different pressures can restore the water contents of clinopyroxene at various levels in the volcanic systems. Subsequently water contents of magmas and mantle sources can be deduced based on crystal/melt partition coefficients. This thesis provides examples from the Canary Islands, Merapi volcano in Indonesia and the famous Nakhla meteorite. Using NAMs as a proxy for magmatic and mantle water contents may provide a very good method especially for planetary science where sample material is limited. The thesis’ second part focusses on analytical methods to measure the concentration of water in NAMs. Specifically the application of Raman spectroscopy and proton-proton scattering are tested. The hydrated mineral zoisite is thoroughly analyzed in order to be used as an external standard material. Polarized single crystal spectra helped to determine the orientation of the OH-dipole in zoisite. Further, Transmission Raman spectroscopy and a new method for the preparation of very thin samples for proton-proton scattering were developed and tested. The results provide new possibilities for the concentration analysis of water in NAMs such as three dimensional distribution and high spatial resolution.

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Diouri, Mohammed. "Treatment of Low Quality Forages by Hydrogen Peroxide and(or) Anhydrous Ammonia and Their Utilization in Ruminant Nutrition". DigitalCommons@USU, 1993. https://digitalcommons.usu.edu/etd/3987.

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Three experiments were conducted to evaluate low quality forages treatment by anhydrous ammonia (NH3) and(or) hydrogen peroxide (H2O2). In experiment I, a control and three treatments of barley straw were compared: NH3, NH3 after rehydration of the straw with water (NH3+H2O), and NH3 after rehydration with a H2O2 solution (NH3+H2O2). Forages were fed, with a supplement, at two levels of intake (ad libitum and 75% of ad lib.). Treatments were administered in a split-plot in a Latin square design to 8 ewes. Total collections and rumen digesta measurements were made. Ammoniation, rehydration, and H2O2 increased primarily dry matter intake (DMI) but also digestibility of different nutrients. A similar trend was observed in rumen fermentation characteristics. Dry matter (DM) digestibility was slightly raised by limiting DMI. Digestible DMI (DDMI) was correlated with both the increase of forage CP content and the decrease of forage neutral detergent fiber. Water intake and output were highly correlated with fiber. Intake and digestibility better than acid detergent lignin insoluble ash (ADLIA). Both markers were adequate in determining hemicellulose digestibility. In experiment II, ten solutions were prepared to rehydrate wheat straw. Six solutions were adjusted (with NaOH) to a pH of 9, 11, or 13 and contained 2% H2O2. Four solutions had a pH of 7 or 11 and contained no H2O2. Half of the straws were treated with NH3. In situ DM disappearance (DMD) of the different straws was measured at different times in 10 Holstein cows and three periods (Incomplete block design). The evolution of DMD was slow and almost linear. The positive effect of ammoniation on DMD was consistently apparent at all pH levels though depressed at pH 11. The effect of H2O2 was minor, but was complementary with ammoniation. In experiment III, mature baltic rush (Juncus balticus Willd.) was either treated or not with NH3. Eight wethers had ad libitum access to the nonsupplemented forages in a cross-over design. total collections and rumen digesta measurements were made. DMI and DDMI were not affected by treatment, but DM digestibility was decreased by ammoniation.

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Zhang, Peipei. "Hydrogen diffusion in NAMs : andradite garnet and zircon". Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10023/document.

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Cette thèse présente les résultats d’une étude de la mobilité de l’hydrogène dans l’andradite entre 400 et 700°C et dans le zircon entre 800 et 1100°C. Contrairement à ce qui est généralement observé dans ce type d’expériences, il n’a pas été possible de remplacer par du deutérium tous les hydrogènes présent dans la structure cristalline sous la forme de défauts ponctuels. A la fin de l’échange 15% à 35% des H dans l’andradite et 25% à 40% des H dans le zircon restent présent. Cependant, un état d’équilibre étant atteint, nous avons pu déterminer les lois de diffusion relative à ces échanges. L’énergie d’activation est comparable à l’énergie d’activation de diffusion de l’hydrogène dans le grossulaire (102 kJ/mol), mais avec une diffusion deux ordres de grandeur plus rapide. Nos résultats montrent que la composition joue un rôle majeur sur la diffusion d’hydrogène dans la série grossulaire-andradite et celle-ci doit impérativement être prise en compte dans toute interprétation des données de δD dans les grenats. Dans le zircon, la diffusion de l’hydrogène est anisotrope, avec une diffusion selon [001] légèrement plus rapide que celle selon [100] et [010]. Le zircon est le MNA qui a la diffusion d’hydrogène la plus lente et qui présente la plus forte énergie d’activation. Lors des expériences d’échange H-D le zircon incorpore également du deutérium parallèlement à la réduction de l’uranium présent dans la structure en suivant la réaction d’hydratation U5+ + OH- = U4+ + O2- + 1/2H2. La cinétique d’incorporation associée est très légèrement plus lente que la cinétique d’échange H-D, suggérant que l’incorporation est ici limitée par la mobilité de l’hydrogène
The hydrogen mobilities in andradite and zircon were investigated by performing H-D exchange experiments under ambient pressure in a horizontal furnace flushed with a gas mixture of Ar/D2(10%). The temperature range investigated was 400˚C-700˚C for andradite and 800˚C-1100˚C for zircon. At contrary to the same type of experiments performed in NAMs, it was not possible to replace all hydrogen atoms in the structure by deuterium, 15% to 35% for andradite and 25% to 40% for zircon of OH remaining after completion of the exchange. However, a steady-state equilibrium was reached at the end of the experiments and it was possible to determine the diffusion law of the exchange process. The activation energy is similar to those of hydrogen diffusion in grossular, but the diffusivity is more than 2 orders of magnitude faster. Our results demonstrate that, composition has a major effect on H diffusion and it must be considered in any discussion of δD signatures in garnets. In zircon, hydrogen diffusion is anisotropic, slightly faster along [001] than along [100] and [010]. H diffusion in zircon has much higher activation energy and slower diffusivity than other NAMs. During H-D exchange zircon incorporates also deuterium. For the first time, the hydration reaction U5+ + OH- = U4+ + O2- + 1/2H2, involving uranium reduction is observed. The kinetics of deuterium incorporation is just slightly slower than hydrogen diffusion, suggesting that the reaction is limited by hydrogen diffusion. It confirms that hydrogen isotopic memory of zircon is higher than other NAMs. Zircons will be moderately retentive of H signatures at mid-crustal metamorphic temperatures

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Johnson, Elizabeth Ann. "Hydrogen in Nominally Anhydrous Crustal Minerals". Thesis, 2003. https://thesis.library.caltech.edu/2124/1/EAJ_Thesis.pdf.

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Systematic infrared and nuclear magnetic resonance investigations of common crustal minerals were undertaken to better understand the geologic significance of minor components of structural hydrous species within these nominally anhydrous minerals.

The absolute hydrogen concentration in three alkali feldspars and eight plagioclase samples was measured with ¹H nuclear magnetic resonance spectroscopy. The mid-infrared integral absorption coefficient was determined to be 15.3 ± 0.7 ppm⁻¹cm⁻², allowing quantitative analysis of OH and H₂O in feldspars with infrared spectroscopy. A survey of hydrous species in igneous feldspars found that feldspars contain structural OH (0-512 ppm H₂O), H₂O (0-1350 ppm H₂O), and NH₄⁺ (0-1500 ppm NH₄⁺) groups as well as fluid inclusions and alteration products. Composition and crystal structure influence the type of hydrous species that can be incorporated into feldspars, but the concentration and speciation of structural hydrogen is at least partially determined by the geologic environment. The diffusivity of H in OH-bearing plagioclase was determined at 800-1000°C (D0=5.7±2.5x10⁻⁴ m²/sec and Q=224±33 kJ/mol). A millimeter-sized volcanic feldspar phenocryst would be expected to lose a significant proportion of its OH concentration on the timescale of a typical eruption (hours to weeks).

The structures and compositions of low albite and ussingite, Na₂AlSi₃O₈(OH), are similar. The strong hydrogen bonding in ussingite is found to be fundamentally different from the hydrogen bonding environment of OH in feldspars. Comparison of the infrared spectra of structural isomorphs reedmergnerite, NaBSi₃O₈, and low albite suggest that OH is incorporated in both structures through protonation of the most underbonded oxygen site.

The concentration of structural OH in diopside was determined for four granulite facies siliceous marble samples from the Adirondacks, New York. Diopside OH concentration increases monotonically with increasing estimated water fugacity for each outcrop.

Hydrogen concentration is correlated to Ti concentration in zoned grossular skarn garnets from Birch Creek, CA. Decrease of Ti and H from garnet cores to rims may be related to the solubility of Ti in the skarn-forming fluid. Skarn garnets from an Adirondacks, NY, wollastonite ore deposit exhibit a large range of OH concentrations broadly related to rock type that are due to recrystallization and partial dehydration.

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"Hydrogen Isotopic Systematics of Nominally Anhydrous Phases in Martian Meteorites". Master's thesis, 2015. http://hdl.handle.net/2286/R.I.29949.

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abstract: Hydrogen isotope compositions of the martian atmosphere and crustal materials can provide unique insights into the hydrological and geological evolution of Mars. While the present-day deuterium-to-hydrogen ratio (D/H) of the Mars atmosphere is well constrained (~6 times that of terrestrial ocean water), that of its deep silicate interior (specifically, the mantle) is less so. In fact, the hydrogen isotope composition of the primordial martian mantle is of great interest since it has implications for the origin and abundance of water on that planet. Martian meteorites could provide key constraints in this regard, since they crystallized from melts originating from the martian mantle and contain phases that potentially record the evolution of the H2O content and isotopic composition of the interior of the planet over time. Examined here are the hydrogen isotopic compositions of Nominally Anhydrous Phases (NAPs) in eight martian meteorites (five shergottites and three nakhlites) using Secondary Ion Mass Spectrometry (SIMS). This study presents a total of 113 individual analyses of H2O contents and hydrogen isotopic compositions of NAPs in the shergottites Zagami, Los Angeles, QUE 94201, SaU 005, and Tissint, and the nakhlites Nakhla, Lafayette, and Yamato 000593. The hydrogen isotopic variation between and within meteorites may be due to one or more processes including: interaction with the martian atmosphere, magmatic degassing, subsolidus alteration (including shock), and/or terrestrial contamination. Taking into consideration the effects of these processes, the hydrogen isotope composition of the martian mantle may be similar to that of the Earth. Additionally, this study calculated upper limits on the H2O contents of the shergottite and nakhlite parent melts based on the measured minimum H2O abundances in their maskelynites and pyroxenes, respectively. These calculations, along with some petrogenetic assumptions based on previous studies, were subsequently used to infer the H2O contents of the mantle source reservoirs of the depleted shergottites (200-700 ppm) and the nakhlites (10-100 ppm). This suggests that mantle source of the nakhlites is systematically drier than that of the depleted shergottites, and the upper mantle of Mars may have preserved significant heterogeneity in its H2O content. Additionally, this range of H2O contents is not dissimilar to the range observed for the Earth’s upper mantle.
Dissertation/Thesis
Masters Thesis Geological Sciences 2015

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"Hydrogen in the Nominally Anhydrous Phases and Possible Hydrous Phases in the Lower Mantle". Doctoral diss., 2019. http://hdl.handle.net/2286/R.I.54920.

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abstract: The transport of hydrogen to the Earth’s deep interior remains uncertain. The upper mantle minerals have very low hydrogen solubilities (hundreds of ppm). The hydrogen storage capability in the transition zone minerals (2 wt%) is high compared to those of the upper mantle. The hydrogen storage in the lower mantle is not well known. The main minerals in the lower mantle bridgmanite and ferropericlase have very low hydrogen storage capacities (less than 20 ppm). In order to further understand the hydrogen storage in the lower mantle, a series of experiments had been conducted to simulate the environment similar to the Earth’s mantle. The experiments with hydrous Mg2SiO4 ringwoodite (Rw) show that it converts to crystalline dense hydrous silica, stishovite (Stv) or CaCl2-type SiO2(mStv), containing ∼1 wt% H2O together with bridgmanite (Brd) and MgO at the pressure-temperature conditions expected for lower mantle depths between approximately 660 to 1600 km. Brd would break down partially to dense hydrous silica (6–25 mol%) and(Mg,Fe)O in mid-mantle regions with 0.05–0.27 wt% H2O. The hydrous stishovite has a CaCl2 structure, which is common among hydrous minerals in the lower mantle. Based on this observation, I hypothesize the existence of hydrous phases in the lower mantle. The experiments found a new hexagonal iron hydroxide (η-Fe12O18+x/2Hx) between the stability fields of the epsilon and pyrite-type FeOOH at 60–80 GPa and high temperature. The new phase contains less H2O, limiting the H2O transport from the shallow to the deep mantle in the Fe–O–H system. Possible hydrogen storage in Ca-perovskite was studied. CaPv could contain 0.5–1 wt% water and the water in CaPv could distort the crystal structure of CaPv from cubic to tetragonal structure. In conclusion, hydrogen can be stored in hydrous stishovite in the shallower depth of the lower mantle. At greater depth, the new η phase and pyrite-type phase would take over the hydrogen storage. The role of CaPv in deep water storage needs to be considered in future studies.
Dissertation/Thesis
Doctoral Dissertation Natural Science 2019

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Huang, Te-Tsai, e 黃德財. "Optimum Operation of Hydrogen Fluoride Reaction Kiln with The Residue of Fluorspar in The Anhydrous". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/44715402594880356342.

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碩士
國立高雄第一科技大學
環境與安全衛生工程所
92
ABSTRACT The reactants of the hydrogen fluoride reacted in the hydrogen fluoride reaction kiln are fluorspar (CaF2) and sulfuric acid (H2SO4). Its product and byproduct are hydrogen fluoride (HF) and anhydrous (CaSO4), respectively. The residuals in the anhydrous are the fluorspar and trace sulfuric acid (less than 0.2%). To control low fluorspar in the anhydrous is important because it can assure the chemical reaction is successful and the anhydrous can be reused. Especially, the low fluorspars can response the chemical reaction completely whether or not. Consequently, the residue of the fluorspar in the anhydrous was selected as an indicator for the process optimization. The control factors in this study were the amount of the fluorspar, the sulfuric acid, reaction retention time and the residue of fluorspar in the anhydrous. In this study, a statistical strategy, including experimental design, regression and response surface approach, was performed for the process optimization in the hydrogen fluoride reaction kiln with the residue of fluorspar in the anhydrous. Based on the results and discussion, the results showed that: 1. The optimum operation of the hydrogen fluoride reaction kiln with the residue of fluorspar in the anhydrous of the two kilns has a consequence. (a) In the input amount that the sulfuric acid were 60 - 65 tons/day, the fluorspar were 50 - 55 tons/day, the reaction retention time was 5 - 6 hours, and the residue of fluorspar in the anhydrous was 4 - 5%, and had a chemical reaction ratio in 96.9 - 98.6%. (b) In the input amount that the sulfuric acid were 70 - 75 tons/day, the fluorspar were 60 - 65 tons/day, the reaction retention time was 5 - 6 hours, and the residue of fluorspar in the anhydrous was 6 - 7%, and had a chemical reaction ratio in 96.2 - 97.9%. 2. The reaction from the sulfuric acid and the fluorspar can get the perfect of chemical reaction ratio. 3. To increase the reaction retention time, it is not only improve the chemical reaction ratio, but also improve the stability of the chemical reaction and increase the production of the hydrogen fluoride.

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Gama, Jabulani Selby. "A thermogravimetric study of the reactions of molybdenum and tungsten disilicides with anhydrous hydrogen fluoride and fluorine". Diss., 2012. http://hdl.handle.net/2263/26272.

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A study of the reactions between molybdenum and tungsten disilicide (MoSi2 and WSi2) with anhydrous hydrogen fluoride and fluorine was carried out to investigate the chemical behaviour of the materials. These two compounds were used as alternatives that resemble the chemical behaviour of uranium silicide (U3Si2). An extensive literature survey of U3Si2 processing techniques is included, which guided the process selection for this work. The thermogravimetric results of a study into the dry fluorination of molybdenum and tungsten disicilides using both anhydrous hydrogen fluoride and dilute fluorine gas as fluorinating agents are reported. For both solids the observed reactions with fluorine follow the thermodynamically predicted routes, in which the formation of the volatile metal hexafluorides, along with gaseous silicon tetrafluoride was observed. The disilicides get fully converted at roughly 300 to 400 °C respectively. The expected products for the reactions of both solids with hydrogen fluoride are solid tungsten metal, solid molybdenum metal, hydrogen gas, and gaseous silicon tetrafluoride. The metal fluorides (WF4 and MoF3) were not obtained because they form at low temperatures only. Therefore the metals of molybdenum and tungsten were obtained as final products respectively from both reactions; and were verified with the aid of XRF and XRD analyses. Mass-transfer phenomena are shown to play a role in the reactions between hydrogen fluoride and both disilicides, preventing unrestrained complete fluorination of the two solids. Kinetic parameters are reported and the rate limiting mechanisms identified. Copyright
Dissertation (MSc)--University of Pretoria, 2012.
Chemical Engineering
unrestricted

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Libri sul tema "Anhydrous hydrogen"

Centre, Bhabha Atomic Research, a cura di. Ionic solvation and alkali metal ion-hydrogen ion exchange equilibria on nafion-117 in anhydrous methanol. Mumbai: Bhabha Atomic Research Centre, 2001.

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Board, United States National Transportation Safety. Hazardous materials accident report: Anhydrous hydrogen fluoride release from NATX 9408, train no. BNEL3Y at Conrail's receiving yard, Elkhart, Indiana, February 4, 1985. Washington, D.C: The Board, 1986.

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United States. National Transportation Safety Board. Hazardous materials accident report: Anhydrous hydrogen fluoride release from NATX 9408, train no. BNEL3Y at Conrail's receiving yard, Elkhart, Indiana, February 4, 1985. Washington, D.C: The Board, 1986.

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Hans, Keppler, e Smyth J. R, a cura di. Water in nominally anhydrous minerals. Chantilly, Va: Mineralogical Society of America, 2006.

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Keppler, Hans, e J. R. Smyth. Water in Nominally Anhydrous Minerals: Reviews in Mineralogy. Mineralogical Society of Amer, 2006.

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Capitoli di libri sul tema "Anhydrous hydrogen"

Hoffman, C. J., e Edward A. Heintz. "Anhydrous Hydrogen Iodide". In Inorganic Syntheses, 180–82. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470132388.ch48.

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Simons, J. H., e Joel Hildebrand. "Anhydrous Hydrogen Fluoride". In Inorganic Syntheses, 134–36. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470132326.ch50.

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Ingrin, Jannick, e Marc Blanchard. "13. Diffusion of Hydrogen in Minerals". In Water in Nominally Anhydrous Minerals, a cura di Hans Keppler e Joseph R. Smyth, 291–320. Berlin, Boston: De Gruyter, 2006. http://dx.doi.org/10.1515/9781501509476-017.

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Karato, Shun-ichiro. "15. Remote Sensing of Hydrogen in Earth's Mantle". In Water in Nominally Anhydrous Minerals, a cura di Hans Keppler e Joseph R. Smyth, 343–76. Berlin, Boston: De Gruyter, 2006. http://dx.doi.org/10.1515/9781501509476-019.

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Smyth, Joseph R. "5. Hydrogen in High Pressure Silicate and Oxide Mineral Structures". In Water in Nominally Anhydrous Minerals, a cura di Hans Keppler e Joseph R. Smyth, 85–116. Berlin, Boston: De Gruyter, 2006. http://dx.doi.org/10.1515/9781501509476-009.

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Mort, A. J., P. Komalavilas, G. L. Rorrer e D. T. A. Lamport. "Anhydrous Hydrogen Fluoride and Cell-Wall Analysis". In Plant Fibers, 37–69. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-83349-6_3.

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Trincado, Monica, e Matthias Vogt. "5. CO2-based hydrogen storage – hydrogen liberation from methanol/water mixtures and from anhydrous methanol". In Hydrogen Storage, a cura di Thomas Zell e Robert Langer, 125–82. Berlin, Boston: De Gruyter, 2018. http://dx.doi.org/10.1515/9783110536423-005.

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Jadhav, Kirtikumar B., Katrina J. Woolcock e Markus Muttenthaler. "Anhydrous Hydrogen Fluoride Cleavage in Boc Solid Phase Peptide Synthesis". In Methods in Molecular Biology, 41–57. New York, NY: Springer US, 2019. http://dx.doi.org/10.1007/978-1-0716-0227-0_4.

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Chu, Y. C., e G. E. Walrafen. "Low-Frequency Raman Spectra from Anhydrous Sulfuric and Chlorosulfonic Acids, and Liquid Water—Disruption of Tetrahedral Hydrogen Bonding—Relation to Water Structure". In Hydrogen Bond Networks, 169–79. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-015-8332-9_17.

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"Hydrogen Chloride, Anhydrous". In Handbook of Compressed Gases, 414–20. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4613-0673-3_33.

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Atti di convegni sul tema "Anhydrous hydrogen"

Vencill, Thomas R., Amand S. Chellappa e Mike R. Powell. "A Compact Membrane Reactor for Producing Pure Hydrogen From Anhydrous Ammonia". In ASME 2004 2nd International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2004. http://dx.doi.org/10.1115/fuelcell2004-2517.

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A significant barrier to the use of fuel cells for portable and small stationary applications is the lack of a supply of pure hydrogen with high specific energy. Anhydrous ammonia is an attractive fuel because it has very high intrinsic specific energy, requires no water for decomposition, and has established distribution channels throughout the world. A compact membrane reactor hydrogen generation system using anhydrous ammonia as a fuel has been developed which produces greater than 99.95% purity hydrogen at a rate sufficient to power a 100 We PEM fuel cell. Ammonia concentrations in the resultant hydrogen product are non-detectable. Hydrogen recovery through the membrane is as high as 80% and the membrane reactor thermal efficiency (LHV) is 70%. The primary features of this system are a catalytic reactor, a hydrogen separation membrane integrated into the reaction chamber, and a catalytic combustion module to provide heat for the ammonia decomposition reaction and subsequent conversion of trace ammonia reject. The membrane reactor is planar in configuration and allows for a simple, single unit design to provide pure hydrogen for fuel cell applications. The total system can provide specific energies of greater than 500 Wh/kg for a 72 hour run making it an attractive solution of portable and long unattended run time applications.

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Duan, Yi. "Hydrogen Isotope Composition of N-Alkanes Generated during Anhydrous Pyrolysis of Peats from Different Environments". In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.619.

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Hewlett, S. G., D. G. Pugh, A. Valera-Medina, A. Giles, J. Runyon, B. Goktepe e P. J. Bowen. "Industrial Wastewater As an Enabler of Green Ammonia to Power via Gas Turbine Technology". In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-14581.

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Abstract This experimental study follows on from detailed Chemkin-Pro numerical analyses assessing the viability of by-product ammonia (NH3) utilization for power generation in gas turbines (GTs). This study looks specifically at NH3 in the industrial wastewaters of steelworks, resulting from the cleansing of coke oven gas (COG). The by-product NH3 is present in an aqueous blend of 60–70%vol water and is normally destroyed. An experimental campaign was conducted using a premixed swirl burner in a model GT combustor, previously employed in the successful combustion of NH3/hydrogen blends, with favorable NOx and unburned fuel emissions. This study experimentally investigates the combustion performance of combining anhydrous and aqueous by-product NH3 in an approximate 50:50%vol blend, comparing the performance with that of each ammonia source unblended. Green anhydrous NH3, a rapidly growing research topic, is a carbon-free energy vector for renewable hydrogen. Some potential benefits of combining the two sources are suggested. Ammonia combustion presents two major challenges, poor reactivity and a potential for excessive NOx emissions. Prior numerical analyses predicted that 15%vol addition of steelworks COG, at an inlet temperature of 550 K, may provide sufficient support for raising the reactivity of the NH3-based fuels, whilst limiting undesirable emissions. Therefore, addition of 10, 15 and 20%vol COG to each NH3-based fuel was investigated experimentally at 25 kW power with inlet temperatures > 500 K, at atmospheric pressure. As nitric oxide (NO) emissions decrease significantly with increasing fuel-to-air ratio, experiments were conducted at equivalence ratios (Φ) between 1.0 and 1.3, the precise range of Φ for each blend being optimized according to the modeling predictions for emissions. Leading blends, anhydrous NH3 with 15%vol COG and the 50:50%vol blend with 15%vol COG, achieved < 100 ppm and < 200 ppm NO respectively. Modest-sized steel plants produce ∼10 metric tons of by-product NH3/day. Aspen Plus was used to model a Brayton-Rankine cycle with integrated recuperation. Adopting typical losses (48% cycle efficiency) and ∼1.2 MPa combustor inlet pressure, the net electrical power generation of 15%vol COG blended with 10 tonnes/day of aqueous industrial NH3 and 25 tonnes/day of anhydrous NH3 (i.e. achieving a 50:50%vol blend) was ∼4.7 MW, ∼47% more power than for the same amount of anhydrous NH3 with 15%vol COG. This significant increase, indicates how industrial NH3 could enable green NH3 to power.

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Kane, Seamus P., Darrick Zarling e William F. Northrop. "Thermochemical and Sensible Energy Recuperation Using Thermally-Integrated Reactor and Diesel-Ammonia Dual Fueling Strategy". In ASME 2019 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/icef2019-7241.

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Abstract Anhydrous ammonia produced using wind power on farms can be a renewable alternative to conventional fertilizers and to fossil fuels used in engine-powered equipment. Although it has been shown that ammonia can be used in dual fuel modes in diesel engines, its inherently low flame speed results in poor combustion efficiency and thus reduces allowable diesel fuel replacement ratios. In this work, a novel method using a thermochemical recuperation (TCR) reactor system to partially decompose ammonia into hydrogen and nitrogen over a catalyst was demonstrated in diesel engine powered tractor. In the experiments, a John Deere 6400 agricultural tractor powered by a non-EPA tier-certified 4045TL diesel engine was operated in dual-fuel mode using anhydrous ammonia as the secondary fuel. Liquid ammonia from a tank was vaporized and heated using a series of heat exchangers and partially decomposed to hydrogen gas before being fumigated into the intake manifold. The catalytic TCR reactor utilized both exhaust waste heat and unburned hydrocarbon heating value to drive the ammonia decomposition process. Engine emissions and performance data were collected across a standard 8-mode test. The engine was operated using diesel only and in dual fuel mode with up to 42% replacement of diesel with ammonia on a lower heating value basis. Engine loading was accomplished using a power takeoff (PTO) dynamometer. Measured brake thermal efficiency was improved by up to 5.0% using thermochemical recuperation, and brake specific CO2 emissions were reduced by up to 44% over diesel-only rates.

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Leighty, William C., e John H. Holbrook. "Renewable Energy Bulk Storage for < $1.00 / KWh Capital Cost as Gaseous Hydrogen (GH2) and Liquid Anhydrous Ammonia (NH3) C-Free Fuels". In ASME 2013 Power Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/power2013-98294.

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Electricity from diverse renewable energy (RE) resources may be converted to gaseous hydrogen (GH2) and anhydrous ammonia (NH3) carbon-free fuels and stored at < $1.00 / KWh capital cost in large, solution-mined salt caverns for GH2 and in large, refrigerated, “atmospheric” liquid surface tanks as NH3. This stored chemical energy is gathered and transmitted and distributed via continental-scale underground pipeline systems and converted to useful work, at residential to industrial scales, via combined-heat-and-power (CHP) plants, via direct space heating and cooling, and as transportation fuels. We thus solve RE’s severe transmission, storage, and integration problems via complete, optimized, systems design — from photons and moving air and water molecules to delivered energy services. We need to supply all energy, not just electricity, from diverse renewable energy (RE) resources, both distributed and centralized, where the world’s richest RE resources — of large geographic extent and high intensity — are stranded: far from end-users with inadequate or nonexistent gathering and transmission systems to deliver the energy. Electricity systems may be suboptimal, technically and economically, at such large scale. Electricity energy storage cannot affordably firm large, intermittent renewables at annual scale, while carbon-free GH2 and liquid NH3 fuels can: GH2 in large solution-mined salt caverns, NH3 in steel surface tanks, both pressurized and refrigerated.

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Hwang, Jeffrey T., e William F. Northrop. "Gas and Particle Emissions From a Diesel Engine Operating in a Dual-Fuel Mode Using High Water Content Hydrous Ethanol". In ASME 2014 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/icef2014-5460.

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Diesel engines running in a dual-fuel fumigation mode using injection of a high volatility fuel into the intake air and direct injection of diesel fuel can reduce NOX and particulate matter emissions. Fuels such as methanol, hydrogen, gasoline, and anhydrous ethanol have been studied as fumigants; however there has been less published regarding the use of high water content hydrous ethanol. Current production of ethanol yields anhydrous (200 proof) ethanol with no water content. The distillation and dehydration processes used to remove excess water from fermented starches during production require large amounts of input energy, reducing the renewability of the resulting fuel. This paper describes an experimental investigation of an aftermarket fumigation system provided by CleanFlex Power Systems, LLC. Experiments to measure gaseous and particulate emissions were conducted using 120 proof hydrous ethanol and non-oxygenated ultra-low sulfur diesel fuel. A John Deere 4045HF475 Tier 2 engine was modified to incorporate the fumigation system in the intake plumbing downstream of the charge-air cooler, just prior to the intake manifold. Data was collected for dual fuel fumigation combustion and compared to diesel only combustion. This study shows that the fumigation system achieved lower levels of NOX and soot proportional to the fumigant energy fraction (FEF), but increased CO and hydrocarbon levels as compared to diesel-only combustion modes. The results suggest that increasing the FEF by using lower water content or better mixing through port-injection may increase the emissions reduction potential of hydrous ethanol fumigation.

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Leighty, William C., John H. Holbrook e James G. Blencoe. "Alternatives to Electricity for GW-Scale Transmission and Firming Storage for Diverse, Stranded Renewables: Hydrogen and Ammonia". In ASME 2010 4th International Conference on Energy Sustainability. ASMEDC, 2010. http://dx.doi.org/10.1115/es2010-90341.

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COP15, Copenhagen, December 09, failed partly for lack of a credible, comprehensive vision for how we may, and must soon, “run the world on renewables”. We cannot, and should not try to, accomplish this entirely with electricity transmission. The world’s richest renewable energy (RE) resources — of large geographic extent and high intensity — are stranded: far from end-users with inadequate or nonexistent gathering and transmission systems to deliver the energy. Electricity energy storage cannot affordably firm large, intermittent renewables at annual scale, while gaseous hydrogen (GH2) and anhydrous ammonia (NH3) fuels can: GH2 in large solution-mined salt caverns, NH3 in surface tanks, interconnected via underground pipelines in RE systems for gathering, transmission, distribution, and end use. Thus, we need to think beyond electricity as we plan new “transmission” systems for bringing large, stranded RE resources to distant markets as annually-firm C-free energy, to empower subsequent efforts to COP15. Recent press has extolled the global RE vision, but without adequate attention to the diverse transmission and storage systems required for achievement. [21] At GW scale, renewable-source electricity from diverse sources can be converted to hydrogen and byproduct oxygen, and/or to NH3, pipelined underground to load centers for use as vehicle fuel and combined-heat-and-power generation on the wholesale or retail side of the customers’ meters. The ICE, CT, and fuel cell operate very efficiently on GH2 and NH3 fuels. USA has extensive extant NH3 pipeline and tank storage infrastructure.

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Leighty, William C. "Alaska’s Renewables-Source Fuel Energy Storage Pilot Plant: Toward Community Energy Independence via Solid State Ammonia Synthesis (SSAS)". In ASME 2013 Power Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/power2013-98290.

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Alaska village survival is threatened by the high cost of imported fuels for heating, electricity generation, and vehicles. During Winter 2007–8, the price per gallon of heating oil and diesel generation fuel exceeded $8 in many villages. Many villagers were forced to move to Anchorage or Fairbanks. Although indigenous renewable energy (RE) resources may be adequate to supply a community’s total annual energy needs, the innate intermittent and seasonal output of the renewables — except geothermal, where available, which may be considered “baseload” — requires large-scale, low-cost energy storage to provide an annually-firm energy supply. Anhydrous ammonia, NH3, is the most attractive, carbon-free fuel for this purpose at Alaska village scale, because of its 17.8% mass hydrogen content and its high energy density as a low-pressure liquid, suitable for storage in inexpensive mild steel tanks. NH3 may be synthesized directly from renewable-source electricity, water, and atmospheric nitrogen (N2) via solid state ammonia synthesis (SSAS), a new process to be pioneered in Alaska.

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Nelson, George J., Comas Haynes e Cameron Miller. "Dilute Ethanol Fueled SOFCs: A Symbiotic Solution Strategy". In ASME 2009 7th International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2009. http://dx.doi.org/10.1115/fuelcell2009-85088.

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Biofuels have been broached as being more commercially viable under the biorefinery concept wherein multiple product streams enhance overall economics. An example of this concept is presented in which solid oxide fuel cells (SOFCs) and bioethanol are explored in light of the symbiotic pairing of these two promising alternative energy thrusts. Mutual benefit is manifested via dilute ethanol fueled SOFCs. Due to high operating temperatures SOFCs reject high quality heat that can be used for indirect internal reformation of ethanol in the presence of sufficient water. Additionally, carbon monoxide present in hydrogen-rich reformate can be used as a fuel through shift to hydrogen. Thus, the optimization of an additional dilute product stream for SOFC applications can contribute to the realization of the bioethanol infrastructure. This contribution is two-fold. First, across a domain of viable operating conditions the use of dilute ethanol can potentially improve SOFC system performance above cell stack performance and enable distributed SOFC generation fueled by dilute ethanol, providing a secondary market for higher energy ratio bioethanol. Second, integrating in-plant SOFC co-generation fueled by a fraction of dilute ethanol diverted from the process stream is shown to improve the energy ratio of bioethanol. This improvement results from the electricity and by-product heat from the SOFC partially offsetting the energy intensive anhydrous ethanol production.

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Hewlett, S. G., A. Valera-Medina, D. G. Pugh e P. J. Bowen. "Gas Turbine Co-Firing of Steelworks Ammonia With Coke Oven Gas or Methane: A Fundamental and Cycle Analysis". In ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-91404.

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Abstract Following on from successful experimental trials employing ammonia/hydrogen blends in a model gas turbine combustor, with favorable NOx and unburned fuel emissions, a detailed numerical study has been undertaken to assess the viability of using steelworks by-product ammonia in gas turbines. Every metric ton (tonne) of steel manufactured using a blast furnace results in approximately 1.5 kg of by-product ammonia, usually present in a vapor form, from the cleansing of coke oven gas (COG). This study numerically investigates the potential to utilize this by-product for power generation. Ammonia combustion presents some major challenges, including poor reactivity and a propensity for excessive NOx emissions. Ammonia combustion has been shown to be greatly enhanced through the addition of support fuels, hydrogen and methane (both major components of COG). CHEMKIN-PRO is employed to demonstrate the optimal ratio of ammonia vapor, and alternatively anhydrous ammonia recovered from the vapor, to COG or methane at equivalence ratios between 1.0 and 1.4 under an elevated inlet temperature of 550K. Aspen Plus was used to design a Brayton-Rankine cycle with integrated recuperation, and overall cycle efficiencies were calculated for a range of favorable equivalence ratios, identified from the combustion models. The results have been used to specify a series of emissions experiments in a model gas turbine combustor.

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Rapporti di organizzazioni sul tema "Anhydrous hydrogen"

Blake, Thomas A., Carolyn S. Brauer e William J. Bachmann, Jr. Chemical Conversion of Anhydrous Hydrogen Fluoride for Safe Disposal. Office of Scientific and Technical Information (OSTI), giugno 2018. http://dx.doi.org/10.2172/1455316.

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Proposed replacement and operation of the anhydrous hydrogen fluoride supply and fluidized-bed reactor system at Building 9212. Draft environmental assessment. Office of Scientific and Technical Information (OSTI), marzo 1995. http://dx.doi.org/10.2172/192544.

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Proposed replacement and operation of the anhydrous hydrogen fluoride supply and fluidized-bed chemical processing systems at Building 9212, Y-12 Plant, Oak Ridge, Tennessee. Office of Scientific and Technical Information (OSTI), settembre 1995. http://dx.doi.org/10.2172/119910.

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