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Abstract  

Solutions of I2 in C6H6 were irradiated with X-rays, in the energy range from 4.6 to 8.0 keV, thus including the characteristic X-ray of Cr /5.412 keV/, just above the L-absorption edge for iodine /5.118 keV/. Yield of iodobenzene and the organic yield of iodine were investigated as a function of I2 concentration and of the absorbed radiation dose. It is found that the formation of iodobenzene, which was the only product detected, is due to the Auger activation of iodine atoms, and not to the radiolytic decomposition of benzene molecules from direct interaction of X-rays.

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Abstract  

Thorium isotopes in seawater are determined by means of adsorption of the Xylenol Orange /XO: H6A/ complex onto XAD-2 resin at pH=3 and the XO concentration of 10–5M, and subsequent purification using an anion-exchange resin, and finally with alpha-spectrometry. The dissolved232Th concentration in the western North Pacific surface water is found to range from 0.8 to 1.2 Bq –1. The adsorbed species of the Th-XO complex under the experimental conditions has a composition of Th/H2A/2 according to the mass balance analysis.

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Abstract  

In the present work
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\dot OH$$ \end{document}
as well as HRO. radicals were generated in the photochemical interaction of 1,2-benzanthracene with
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\dot OH$$ \end{document}
radicals were trapped by C6H6. The main reaction of HRO. radicals is hydrogen abstraction from the hydroperoxide group of HROOH. Although OH radicals are less selective, the hydrogen abstraction is the main process during their interaction with aromatics in contrast to reactions in aqueous solutions, where addition to the benzene ring is the rate-determining process in CCl4:
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\begin{array}{*{20}c} {k_{\dot OH + HRO\underline {OH} } /k_{\dot OH + \underline {HR} OOH} = 2.5 \pm 0.5 and} \\ {k_{\dot OH + C_6 H_6 } /k_{\dot OH + \underline {HROOH} } = /1.2 \pm 0.15/xlo^{ - 2} .} \\ \end{array}$$ \end{document}
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Abstract  

The complexes of yttrium and lanthanide with 1,1-cyclobutanedicarboxylic acid of the formula: Ln2(C6H6O4)3nH2O, where n=4 for Y, Pr–Tm, n=5 for Yb,Lu, n=7 for La, Ce have been studied. The solid complexes have colours typical of Ln3+ ions. During heating in air they lose water molecules and then decompose to the oxides, directly (Y, Ce, Tm, Yb) or with intermediate formation. The thermal decomposition is connected with released water (313–353 K), carbon dioxide, hydrocarbons(538–598 K) and carbon oxide for Ho and Lu. When heated in nitrogen they dehydrate to form anhydrous salt and next decompose to the mixture of carbon and oxides of respective metals. IR spectra of the prepared complexes suggest that the carboxylate groups are bidentate chelating.

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Journal of Thermal Analysis and Calorimetry
Authors:
J. P. Bastide
,
K. Ezzemouri
,
J. M. Létoffé
,
P. Claudy
, and
A. Bouamrane

The thermal behaviour of complexes [Li+-EC](AlH4) withEC=12-C-4, 15-C-5, DC 18-C-6 (cis-anti-cis andcis-syn-cis isomers) was investigated by Differential Scanning Calorimetry (DSC). These complexes were prepared as solids from benzene solutions. Pure EC and several solvated species [Li+-EC](AlH4)·nC6H6 (EC=15-C-5, DC 18-C-6syn) were also studied. DSC has revealed various phenomena. Solid-solid transitions were observed before melting for [Li+-EC](AlH4) withEC=12-C-4 and 15-C-5. They are probably explained by small molecular modifications strongly dependent on the thermal history of the sample. A glass-transition was found for the pure crown-ether DC 18-C-6anti, the complex [Li+-EC](A1H4) withEC=DC-18-C-6anti and the two solvates mentioned above.

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Abstract  

Polyether-urethane samples were irradiated at the dose range from 10 to 2000 kGy by 2 MeV electron beams. Volatile species from the polymer degradation were analyzed quantitatively and qualitatively with GC/MS. Thermal properties and micro-phase separation of the samples were examined by TG and the morphology was studied by TEM and SEM. The results show that the irradiated polyether-polyurethane evolves CO2, H2, CH4 and C2H6, etc. The thermal stabilities between the hard and soft segments in the irradiated samples are different. At high doses, the phase separation in the sample is predominant and the hard segment of sample is more stable. The dose rate affects the soft segment of the irradiated sample much more.

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Abstract  

The hydrolytic products of manganese carbide Mn7C3 are hydrogen and a number of paraffins of the series CH4, C2H6, C3H8, etc., whose concentrations characteristically decrease with increasing number of carbon atoms in the hydrocarbon molecule. A radioanalytical method applied after Mn7C3 hydrolysis by tritium, oxide has revealed that an analogous series of olefins in trace concentrations is formed as well. It has been confirmed that the sum of the concentrations of hydrocarbons higher than C4 corresponds to the trend of the series. A stoichiometric and structurally consistent radical mechanism of Mn7C3 hydrolysis is proposed as derived from the composition of the hydrolytic products. The initial components of the radical reactions could be CH 2 ¨ and CH 3 · radicals. The statisical and combinatorial aspects of the mechanism are also discussed.

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Abstract  

The oxidation of
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$k_{1_{0_2 + \alpha - naphthol} }^{overall}$$ \end{document}
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$k_{1_{0_2 + \beta - naphthol} }^{overall}$$ \end{document}
1×105M–1s–1, as it has been calculated. Long-lived intermediates have not been observed in C6H6.
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Abstract  

This paper describes first the application of neutron depth profiling (NDP) for measuring the distribution of6Li in LiAlO2 ceramics. Using a surface barrier detector for detecting3H produced in6Li(n, )3H,6Li was profiled to a depth of 14 m in the ceramics. Secondly, a new methodology is presented for NDP with enhanced capabilities based on measuring the energy of recoiling nuclei from (n, p) and (n, ) reactions by time-of-flight mass spectrometry. The scope of recoil nucleus time-of-flight mass spectrometry (RN-TOF-MS) includes profiling of10B,14N,17O,33S,35Cl,40K. Probe depths may be of a few tens nanometers. RN-TOF-MS complements and refines NDP based on charged particle (p or ) spectrometry.

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Abstract  

Reaction of recoild38Cl atoms with o-dichlorobenzene in the presence of carbon tetrachloride or iodine has been studied by using radio-high performance liquid chromatography. The major products were detected by a 4-channel-wavelengths spectrophotometric detector. The radioactivity of38Cl compounds including minor products was measured with a NaI(T1) scintillation detector. The main products found were38Cl labeled HCl/Cl2, CHCl3, CCl4, o-, p-, m-C6H6Cl2 and polymer, whereas only minor products such as HCl/Cl2, CHCl3, C2Cl6, C6H3Cl3, and polymer were found in the radio-chromatogram. The reaction mechanisms of recoil38Cl atom are briefly described.

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