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91.
Yu. V. Maksimuk V. D. Sokolov V. M. Sevruk P. K. Trahanov 《Journal of Thermal Analysis and Calorimetry》2001,65(3):965-970
The enthalpies of combustion for 4-formylbenzoic acid (I), 4-methylbenzyl alcohol (II), and trimethyl 1,2,4-benzenetricarboxylate
(III) were determined by the bomb calorimetry method. Enthalpies of sublimation for I and II were measured with a calorimeter.
The contributions of different substituents to the standard enthalpies of formation for benzene derivatives in the gas state
were derived.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
92.
93.
Carbon Dioxide (CO2) laser-induced decomposition of ethoxy(trimethyl)germane (ETG) results in a substantial stripping of organic substituents from germanium and leads to deposition of organogermanium films, the composition of which is dependent on the mode of laser irradiation. Direct absorption of laser radiation in ETG affords material rich in Germanium, while a sulfur hexafluoride (SF6)-photosensitized process produces a deposit composed of Germanium, Carbon, Hydrogen and Oxygen. The deposited materials can be modified by chemical reactions with acetic anhydride and atmospheric moisture. 相似文献
94.
95.
3 ,5 ,5 三甲基己酸甲酯是一种具有特殊用途的精细化工中间体 ,常作为香料 ,通常采用羰化氧化、酯化法。但收率较低、反应周期长。国内外针对直链烯烃氢酯基化反应的研究较多[1~ 4] ,而对于支链烯烃的研究特别是对支链度较高的烯烃而言报道相对较少。本文首次探索出用氢酯基化一步合成 3 ,5 ,5 三甲基己酸甲酯的方法 ,达到简化生产环节 ,提高产品收率的效果。1 实验部分1 1 原料二异丁烯 (工业级 ,纯度 >99% ,其中内烯烃为 1 5 % ,由山东厂家提供 ) ;甲醇 (工业级 ,纯度 >97% ,由兰化化肥厂提供 ) ;催化剂Co2 (CO)8(由工业氧化钴… 相似文献
96.
混合模板剂合成钛硅分子筛 总被引:3,自引:0,他引:3
以钛酸正丁酯为钛源,正硅酸乙酯为硅源,在443K用罩丙基溴化铵和四乙基氢氧化铵的混合物的为模板剂,合成了Ti-Si分子筛。经XRD,FT-IR,SEM以及BET比表面积分析,证实了在以TPABr+TEAOH为模板剂合成的样品中钛已进入silicalite-1的骨架,而以TPABr+二乙胺或三甲胺为模板剂则合成不出Ti-Si分子筛。SEM的结果表明用氨水和TEAOH调节反应液的碱度,对晶体的生长和形 相似文献
97.
制得了二丁胺甲基膦酸-亚磷酸氢锆Zr(HPO3)2-x.(O3PCH2NBu2).H2O(x=0.8,0.6,0.5,0.4,0.35),用溴化苄季铵化,得部分季铵化产物,溴化苄基二丁铵甲基膦酸-二丁胺甲基膦酸-亚磷酸氢锆Zr(HPO3)2-x.(O3PCH2NBu2)x-y.(O3PCH2N^+Bu2.CH2Ph.Br^-).H2O(y<x),用作相转移催化剂,对液/液或固/固/液相转移催化的取 相似文献
98.
Chin-Ping Yang Jiun-Hung Lin 《Journal of polymer science. Part A, Polymer chemistry》1995,33(14):2425-2433
Fifteen bis(phenoxy) fluorene-containing poly(amide-imide)s III were synthesized by the direct polycondensation of 9,9-bis[4-(4-aminophenoxy)phenyl]fluorene (BAPPF) with var-ious aromatic bis(trimellitimide)s II in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly(amide-imide)s III having inherent vis-cosities up to 1.45 dL/g were obtained in quantitative yields. Most of the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All the soluble poly(amide-imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 263–315°C and the 10% weight loss temperatures were above 510°C in nitrogen. Some properties of poly(amide-imide)s III were compared with those of the corresponding isomeric poly(amide-imide)s III ′ prepared from 9,9-[4-(4-trimellitimidophenoxy)phenyl]fluorene and various aromatic diamines. © 1995 John Wiley & Sons, Inc. 相似文献
99.
De-Zhi?SunEmail author Shi-Bing?Wang Ming-Zhi?Song Xi-Lian?Wei Bao-Lin?Yin 《Journal of solution chemistry》2005,34(6):701-712
Interactions between α-CD and three alkyl trimethyl ammonium bromides, a homologues series of surfactants, in aqueous solutions have been investigated with titration microcalorimetry at 298.15 K. The results are discussed in the light of the amphiphilic interaction and the iceberg structure of water molecules existing around the hydrophobic tail of the surfactant. The stoichiometry of the host–guest complex changes from 1:1 to 2:1, as the number of carbon atoms (n) in the hydrophobic chain, CnH2n+1, increases from 8 to 14. All the complexes are quite stable, with the apparent experiential stability constants being β1 = 2.65 × 103 dm3-mol−1, β2 = 4.85 × 106 dm6-mol−2, β2 = 6.50 × 106 dm6-mol−2, respectively for n = 8, 12, 14. All the complexation processes are shown to be enthalpy driven, and the standard enthalpy effect (−ΔH0) increases while standard entropy change (ΔS0) decreases with elongation of the hydrophobic chain. 相似文献
100.
In the work described in this paper, 7-hydroxyflavone and chrysin were phosphoylated by a modified Atheron-Todd reaction. Three new phosphorylated flavonoids (PF) were obtained, and the structures of the target products were determined by X-ray and NMR data and electrospray ionization (ESI) tandem mass spectroscopy (MS). The mixed solutions of the phosphorylated flavonoids and different proteins such as insulin, lysozyme, and cytochrome c were injected in an ion trap mass spectrometer. The results show that all the phosphorylated flavonoids could form non-covalent complexes with the proteins mentioned above, while non-covalent complexes were not detected from the mixed solution of the chrysin or 7-hydroxyflavone with proteins. The research shows that the phosphorylated flavonoids could enhance the interaction with proteins. It may imply their important role in biological processes. The method described in this paper provides us additional information for studying such interactions for phosphorylated flavonoids in this important field. 相似文献