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111.
硫酸氢铵分解动力学及其分解机理的研究 总被引:1,自引:0,他引:1
为了筛选适合的化学贮能系统,Wentworth等人曾提出了十项筛选标准。照此标准衡量,硫酸氢铵的分解-合成反应是一个十分理想的贮能系统: NH_4HSO_4(l)?NH_3(g)+H_2(g)+SO_3(g)Prengle也曾就此反应应用于太阳能电站贮能系统的可行性作过理论上的探讨.但是,有关该反应的基础研究进行的还很不够,特别有关分解动力学和分解机理的研究文献尚未见报导。本文用等温热重法和程序升温热重法对硫酸氢铵的热分解动力学进行了研究,并确定了分解机理,为贮能系统的实际应用提供了基础数据。 相似文献
112.
113.
Using the chemiluminescence oxidation of U(IV) and H2O2 with xenon trioxide as a model, it has been found that during the photolysis of solutions of UO2SO4 in sulfuric acid in the absence of any organic compounds, the accumulation of U(SO4)2 and H2O2 takes place as a result of the reaction of the primary products of the photoreduction of uranyl ion,i.e., UO2
+ and the OH radical.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 751–754, April, 1994.The work was financially supported by the Russian Foundation for Basic Research, Project 93-03-12291. 相似文献
114.
115.
Maiorova N. A. Khazova O. A. Tarasevich M. R. 《Russian Journal of Electrochemistry》2004,40(10):1060-1065
The kinetics of the hydrogen oxidation and the CO adsorption on a Pt (ultra)microelectrode is studied in a 0.5 M H2SO4 solution saturated with a mixture of gaseous H2 and CO at partial CO pressures p
CO = 10–500 ppm. The balance between rates of diffusion and adsorption of CO at different adsorption times is studied. Studied is the effect of CO impurities in H2 on steady-state polarization curves for the hydrogen ionization and nonsteady-state curves of the oxidation current decay with time at 0.02–0.05 V. Conditions under which in a certain time interval and at a certain CO concentration the slope of an I vs. t curve is proportional to p
CO are determined. The obtained dependence may be used when designing a technique for monitoring CO impurities in technical hydrogen. 相似文献
116.
Cl···O intramolecular contacts are analysed here. Hence the Cambridge Structural Database (CSD) search was performed to find
five-membered Cl–C=C–C=O pseudo-rings closed through Cl···O intramolecular contacts. Such rings were analysed and it was found
that some of Cl···O distances are smaller than the corresponding sum of van der Waals radii. Additionally ab initio MP2/6-311++G(d,p)
calculations and AIM analyses were carried out here on 3-chloropropenal and its fluoro derivatives to deepen the nature of
intramolecular Cl···O interactions, some of findings may indicate that they are attractive and stabilizing ones.
This paper is dedicated to Prof. T. M. Krygowski on the occasion of his 70th birthday 相似文献
117.
Masafumi Unno Hiroyuki Murakami Satoshi Kagawa Hideyuki Matsumoto 《Silicon Chemistry》2007,3(3-4):195-198
Two new silanols bearing very bulky silyl groups, (i-Pr3
Si)3SiOH and (t − BuMe2Si)3SiOH were prepared by peracidoxidation of their respective silanes. The X − ray crystallographic analysis revealed that (t − BuMe2Si)3 SiOH forms a dimeric structure with hydrogen bonding, while (i − Pr3 Si)3 SiOH exists as a monomer in the crystal. The effects of the size of the substituents as well as the reactivity of these silanols
are discussed. 相似文献
118.
Rat V. André P. Aubreton J. Elchinger M.F. Fauchais P. Lefort A. 《Plasma Chemistry and Plasma Processing》2002,22(4):453-474
The calculation of two-temperature transport coefficients in an argon–hydrogen plasma at atmospheric pressure is performed using a new theory of two-temperature transport properties recently presented. The latter takes into account the coupling between electrons and heavy species, coupling neglected in the already existing theories of Devoto and Bonnefoi. Transport coefficients are calculated at two-temperatures, the kinetic temperature of electrons Te being different from that of heavy species Th. This paper is divided into two parts. The first one is related to elastic processes and its aim is to compare the results obtained with this new theory for viscosity , translational thermal conductivities tr
e and tr
h and electrical conductivity with the previous results of Bonnefoi. The composition is calculated with the modified equilibrium constant of van de Sanden et al. and the most recent interaction potential are discussed. As it could be expected the electron translational thermal conductivity and the electrical conductivity calculated when taking into account or not the coupling between electrons and heavy species show non-negligible discrepancies. Besides this comparison, the results also show the drastic influence of the non-equilibrium parameter =Te/Th on the values of , , tr
e, and tr
h. 相似文献
119.
Dr. László Beda 《Journal of Thermal Analysis and Calorimetry》1995,44(2):513-516
The curing of composition containing epoxy bond is complicated chemical and technological process where under temperature and pressure conditions a change of its structure occurs. The structure changes are possible to know by thermal methods as DSC, DTA, etc. and also by measurement of dielectrical response under the low frequency electrical field. 相似文献
120.