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Abstract  

A new method for hydrogen content control over UO2 based on laser microsampling in a noble gas flow as well as independent ways of hydrogen detection are proposed. Solid electrolytic cell and a metal-insulator-semiconductor sensor are used for hydrogen registration. The limit of detection is about 10–11 g H2... The results received by the two analytical procedures do not show considerable systematic discrepancy.

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Introduction Catalytic hydrogenation is widely used to chemically modify the properties of fats and oils or to obtain valuable chemical products. One of such product types are unsaturated fatty alcohols. Unsaturated fatty

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Abstract  

A procedure has been developed to use the recoiled protons produced in neutron-proton scattering process for fast, nondestructive determination of the hydrogen contents of coal samples. Samples from Hungary, Poland and Russia have been bombarded with 2.85 MeV neutrons from a small home-made neutron generator and the recoiled protons detected by a simple surface barrier detector. To convert proton counts into hydrogen content, a calibration procedure was established for the method using prepared standards of known hydrogen content and range for 2.85 MeV protons. Exploratory results obtained by this method compare favourably with those obtained by the neutron reflection method.

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the interest to develop environmentally benign, simple, selective, economical methods using environment friendly and cheap oxidants like molecular oxygen (O 2 ) and hydrogen peroxide (H 2 O 2 ). O 2 is one of the cheap and abundantly available

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Abstract  

Mixed rare earth hydrogen selenite crystals, neodymium praseodymium hydrogen selenite (NdxPr1−x(HSeO3)(SeO3)⋅2H2O), Neodymium samarium hydrogen selenite (NdxSm1−x(HSeO3)(SeO3)⋅2H2O) and praseodymium samarium hydrogen selenite (PrxSm1−x(HSeO3)(SeO3)⋅2H2O) were prepared by gel diffusion technique. Simultaneous thermogravimetric and differential thermal analysis were carried out on the grown crystals. Decomposition is observed to occurs in six steps, which gives the evidence of successive losses of H2O and SeO2. The final product due to decomposition is a mixed rare earth oxides. FT-IR spectrum of the crystal samples heated at different temperatures complemented to the TG-DTA results.

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Abstract  

The present study explores the characteristics of hydrogen energy literature from 1965 to 2005 based on the database of Science Citation Index Expanded (SCIE) and its implication using the bibliometric techniques. The results of this work reveal that the literature on hydrogen energy grows exponentially with an annual growth rate of about 18% for the last decade. Most of document type is in the form of journal articles or meeting abstracts, constituting 90.17% of the total literature and English is the predominant language (94.66%). USA, Japan and China are the three biggest contributing countries on hydrogen energy literature publishing, 25.8%, 14.9%, 7.7%, respectively. The Chinese Academy of Sciences in China is the largest contributor publishing 308 papers. The journal literature on hydrogen energy does not confirm the typical S-shape for the Bradford-Zipf plot, but five core journals, i.e. International Journal of Hydrogen Energy, Journal of Power Source, Journal of the Electrochemical Society, Solid State Ionics, and Electrochimica Act, contributing about 41% can be identified. Journals with highly cited articles and most highly cited articles are also identified, in which the most highly cited article receives more than 1,000 citations.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Lun-cun Wei, Yun-cheng Zhong, Jian-wei Han, Bin Liang, Xiao-tang Ren, Jin-xiang Yu, and Ren-xing Li

Abstract  

By using the coincident measurement, an ERD method has been established and used for hydrogen profiling in thin foils. In the present study, 6 MeV has been used as incident particle, the scattered and the recoiled proton from one collision were coincidentally detected at 150 (proton) and 173.9 (). This method has been used for hydrogen profiling of 5.6 m Mylar and 8.6 m aluminium foils. Because of the coincident measurement, the background is largely reduced, and its minimum detection limit is about 0.5% (atomic), lower than the conventional ERD method. The measured depth resolution in 5.6 m Mylar is 0.6 m. It is possible to use this method for hydrogen profiling in thin foils of several micron thickness.

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Abstract  

Copper chromite catalysts were prepared by using a new metal organic precursor, M(OR)n, which was dissolved in organic solvent, hydrolysed and condensed to form inorganic polymers containing M-O-M linkages. In the cases of Ba and Mn promotion, the corresponding metal oxide was admixed to the copper-chromium solution prior to gelification. After drying in helium atmosphere, the precursor was subjected to thermal treatment at different temperatures (373-873 K) and in different atmospheres (air, nitrogen or hydrogen). Both the catalysts and the industrial Engelhard catalyst were characterized by various techniques (TG-DTA, HTXRD, IR, BET, metallic copper surface area and porosimetry measurements) and evaluated for ester hydrogenation.

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Abstract  

The hydrogen concentration for the reference material low-alloy steel was estimated using prompt gamma neutron activation analysis. The hydrogen concentration had a range of 0.91–1.14 mg/kg as measured by the prompt gamma activation method but the reference value was about 1.0 mg/kg as measured by the ICP/AES method. The relative error appeared to be 14% and the differences showed as the background by blank. The standard reference material (NIST SRM) was used for the analytical control.

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Abstract  

The use of heavy ion activation as a method for the analysis of hydrogen and deuterium has been evaluated. Thick target yields from reactions of7Li,10B,11B and19F on1H and2H have been determined; activation curves for many of these reactions are presented and interferences are evaluated. Hydrogen has been determined in titanium via1H(10B, α)7Be at the 100 and 33 ppm levels with relative precisions of 8 to 10%.

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