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991.
热处理对Co(Ni)-Mo/Al2O3催化剂加氢脱硫活性的影响 总被引:9,自引:0,他引:9
介绍了硫化Co-Mo/Al2O3催化剂的热处理方法及其结果。实验表明,硫化催化剂经热处理后,加氢脱硫活性明显增加,以塞吩转化率表示的催化活性随处理温度升高而变化,在450℃时观察到催化活性的极大值。 相似文献
992.
A. Koiwai H. Miyaji T. Asahi K. Asai Y. Miyamoto 《Journal of inclusion phenomena and macrocyclic chemistry》1986,4(3):255-264
The decomposition of urea adducts with hydrocarbons is treated as a first-order phase transition and the pressure dependence is studied up to 0.7 GPa for several kinds of adducts. The thermodynamic quantities at the decomposition of the adduct can be analysed as a sum of those quantities of the component materials. The transition from the orthorhombic to the hexagonal form of the adduct with polyethylene is also investigated by X-ray diffraction and the pressure dependence of the lattice parameters is measured for the adducts. The results are compared with the phase transition in the pure paraffin. 相似文献
993.
Complexes of azobisisobutyronitrile (AIBN) with titanium tetrachloride and vanadium tetrachloride have been synthesized and characterized. It was demonstrated that Ti(IV) and V(IV) form equimolar complexes with AIBN, with nitrile ligands located incis positions in the coordination spheres of metal atoms. Kinetics of thermal decomposition of free and complexed AIBN were studied and compared. The gas evolution rate was measured in the presence of tetrabutoxytitanium, which does not react with AIBN. It was demonstrated that complexing leads to a marked increase of the rate constant of AIBN thermal decomposition.Institute of Chemical Physics, Chernogolovka, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1746–1754, August, 1992. 相似文献
994.
995.
Anorgano modifiedMgAl layereddoublehydroxide (OMgAl LDH )wassuccessfullyexfoliatedinthexylenesolutionofpolyethylene grafted maleicanhydride (PE g MA )underre fluxingcondition .APE g MA/MgAl LDHexfoliationnano compositewasformedaftertheprecipitationofPE g MAfromthedispersionsystem .ThestructureandthermalpropertyofthePE g MA/MgAl LDHexfoliationnanocompositewerechar acterizedbyX raydiffraction (XRD ) ,transmissionelectronmicroscopy (TEM ) ,andthermogravimetryanalysis (TGA ) .The… 相似文献
996.
利用波长为266nm的激光光解CHBr3产生CH自由基,其与NO反应作为NCO自由基的来源.在298K,总压2660Pa的条件下,采用激光诱导荧光的方法,研究了NCO自由基与SO2、CS2的反应.得到了NCO自由基与SO2、CS2双分子反应速率常数分别为(1.8±0.3)×10-11和(3.1±0.4)×10-12cm3·molecule-1·s-1.对这两个反应在B3LYP/6-31 G(d)的水平上进行理论研究的结果表明,NCO自由基与SO2、CS2的反应是加成反应,其机理是NCO自由基中的N原子攻击反应物的中心原子,得到加成产物. 相似文献
997.
998.
D. Zivkovic L. Katsikas J. S. Velickovic I. G. Popovic 《Journal of Thermal Analysis and Calorimetry》1993,40(2):767-772
The non-oxidative thermal degradation of poly (di-2-chloroethyl itaconate) (PD2CEI) was studied by TG and by analysing the thermal products. The major processes occurring during thermal analysis are crosslinking, depolymerisation and carbonisation. The thermal degradation activation energy increased with increasing sample mass loss. The thermal degradation of PD2CEI was compared to that of the structurally similar poly(2-chloroethyl methacrylate) (P2CMA). 相似文献
999.
J. Bujdák H. Slosiariková B. Číčel 《Journal of inclusion phenomena and macrocyclic chemistry》1992,13(4):321-327
Reduced charge montmorillonites (RCM) were prepared using lithium thermal treatment. The sorption of octylammonium (OA), dodecylammonium (DDA) and hexadecylammonium ions (HDA) on differently charged samples were studied. The amounts of DDA and HDA sorbed on each RCM exceed the cation exchange capacity (CEC) but that of OA exceeds only the CEC of samples with the lowest CEC. The sorption is affected not only by the layer charge but also by the formation of collapsed interlayer spaces in the lowest charged montmorillonites. X-ray measurements confirmed the decrease of the layer charge after lithium thermal treatment and the layer charge heterogeneity in RCMs. 相似文献
1000.
Attempts to miniaturize electrophoresis (EP) to save time or enhance productivity and efficiency remains a challenge for science
and industry. Other advantages of miniaturization include: increased sensitivity, saving of reagents, greater yield of data,
and enabling studies where only small samples are available. Since electrophoresis that takes hours may be reduced to a matter
of minutes, the limitations of miniaturization in clinical, industrial, and research applications are evaluated. Clinical
electrophoresis (EP) on cellulose acetate media can be performed in 3.5 min instead of 20–45 min and on SDS polyacrylamide
gels in 15–30 min compared with conventional 3–8 h. 相似文献