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Journal of Thermal Analysis and Calorimetry
Authors: Laetitia Laversenne, Christelle Goutaudier, Rodica Chiriac, Catherine Sigala, and Bernard Bonnetot

Abstract  

The hydrogen storage capabilities of alkaline borohydrides through a hydrolyzing process were determined by taking into consideration the hydration of the end products. Comparison of LiBH4, NaBH4 and KBH4 showed their storage capacities to be dependent on the composition of the metaborate formed. This composition is ruled by the hydrolysis conditions, especially the temperature reached during the reaction and the stability of the hydrates. The borohydride with the highest hydrogen content in the solid state, LiBH4, could be less efficient than KBH4 if the hydrolysis is performed at 120°C.

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Abstract  

Effect of hydrolysis time on molar mass, glass transition temperature, crystallinity, and resistance to thermooxidation at elevated temperatures was analyzed for Estanes 54600, 54610, and 54650. Kinetics of the hydrolysis can be plausibly described in terms of the first-order reaction with an average induction period of about 7 days. Reduction of molar mass induced by hydrolysis brings about an appreciable decrease in glass transition temperature, fraction of crystalline domains of soft segments, and thermooxidative stability. The latter effect is manifested by shortening of the lifetimes (related to 5% mass loss) the temperature dependence of which obeys the Arrhenius plot. The observed differences in hydrolysis resistance of Estanes can be related to their chemical composition.

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Abstract  

The purpose of this study was to conduct a thermal analysis of the hydrolysis and degradation behavior of biodegradable polymers and bio-composites at 50°C and 90% relative humidity (RH). With increasing hydrolysis time, the thermal stability and degradation temperature of polybutylene succinate (PBS) slightly decreased. The glass transition temperature (T g) and melting temperature (T m) of PBS and the anti-hydrolysis agent treated PBS did not vary significantly with increasing hydrolysis time, whereas those of the trimethylolpropane triacrylate (TMPTA)-treated PBS slightly increased. With increasing hydrolysis time, the storage modulus (E’) values of the bio-composites decreased, whereas those of the TMPTA treated bio-composites slightly increased. Also, the tan values of the anti-hydrolysis agent and TMPTA treated PBS-BF bio-composites were slightly lower than those of the non-treated bio-composites, due to the reduction in their degree of hydrolysis. The tanδmax peak temperature (T g) of the anti-hydrolysis agent treated bio-composites was not significantly changed, whereas that of the TMPTA treated bio-composites was increased.

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Abstract  

A generalized scheme of americium(III) hydrolysis is proposed for a wide range of pH (1–10) and concentrations (10–1–10–10M). The data on Am(III) hydrolysis are presented in the form of three-dimensional isothermal diagram. This approach to the study of hydrolysis can be used for investigation of hydrolytic behaviour of most polyvalent ions.

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. , Bing , L. & Yong , K. ( 2013 ): Effects of combination of SE and MW irradiation (SE-MI) pretreatment on enzymatic hydrolysis, sugar yield and structural properties of corn stover . Ind. Crop. Prod. , 42 , 402 – 408

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Abstract  

The first hydrolysis constant (pK1h = 9.4) of Ac3+ cations has been determined using 228Ac radiotracer. The pK1h value of Ac3+is compared to the pK1h values of other Group 3 cations. It is shown that, in contrast to the Group 2, 11, 12 and 13, the heaviest member of the Group 3 Ac3+ hydrolyses at less extent than its lighter homologs. The linearity of the log K1h-1/r i (where r i is the ionic radius) function indicates that the electrostatic model of hydrolysis describes well the hydrolysis of Group 3 cations.

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, J. , Shalaby , S.M. , Zakora , M. , Pripp , A.H. & El-Shabrawy , S.A. 2007 : Angiotensin-converting enzyme inhibitory activity of milk protein hydrolysates: Effect of substrate, enzyme and time of hydrolysis . Int. Dairy J

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Introduction The hydrolysis of carboxylic acid esters is one of the most studied chemical reactions because of its importance both in chemistry and biochemistry [ 1 – 9 ]. The available catalysts used for the hydrolysis of

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the body and injured gastrointestinal function, it is particularly appropriate to use pre-digested proteins, where pre-hydrolysis mimics the gastrointestinal digestion processes. Food containing peptides does not cause such hypertension as free amino

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