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Crystallography Reports - A cobalt coordination polymer, {[Co(L1)2(H2O)2] · (HCOO)2 · H2O}n, where L1 is a bis(4-(1H-imidazol-1-yl)phenyl)methanone, has been synthesized and characterized... 相似文献
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CAI Guang-Yu LlU Zhong-Min SHI Ren-Min HE Chang-Qing YANG Li-Xin SUN Cheng-LinDalian Institute of Chemical Physics Acadernia Sinica Dalian Iiaorting 《天然气化学杂志》1995,(2)
A new route named as SDTO method for the synthesis of lightolefins from syngas has been proposed.That is to convert syngas todimethylether and then to convert dimethylether to light olefins.The catalystsfor the two conversion reactions have been developed.For the first reaction,the catulySt was synthesized by the combination of methanol synthesis catalystwith γ-Al_2O_3or zeolites which possesses both metallic and acidic functions.Thecatalyst for the second reaction was modified SAPO-34 molecular sieve.Thevariables of the reactions have also been investigated.The results from theserial connection of the two conversion steps without any separation show thatthe yield of C_2~-C_4~- olefins Could be>100g/(m~3 syngas). 相似文献
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原油饱和烃指纹的内标法分析 总被引:3,自引:1,他引:3
采用内标法建立了原油中正构烷烃、生物标志物(甾、萜烷类)的分析方法。确定了样品前处理方法和组分定性定量方法。讨论了柱层析分离能力。结果表明,所有饱和烃组分均流入第一部分流出液F1中,分离能力较为满意。对48种甾、萜烷类生物标志物组分以及姥鲛烷、植烷和正构烷烃等进行了定性确认,定性化合物数量多,信息量大,易于据此进行可靠的油指纹分析鉴别。32个正构烷烃组分相对标准差为1.2%~7.4%;45个生物标志物组分相对标准偏差为2.5%~9.2%。分析精密度较好,满足油指纹鉴别需要。正构烷烃回收率为73%~116%;生物标志物为84%~106%;回收率结果较为满意。正构烷烃方法检出限为7.0μg/g;生物标志物为0.65μg/g,满足原油样品分析要求。通过本方法对自不同和相同平台的原油样品进行饱和烃浓度分析,并采用浓度数据进行鉴别,结果与实际情况相符。 相似文献
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WANG Hai-Yan XIAO Yi LI Yan-Mei WU Li-Xin YU Zhi-Wu ZHAO Yu-Fen 《有机化学》2003,23(Z1):197-197
Self-assemblies of amphiphilic molecules are proposed to play a ubiquitous role at the early stages of evolution in the formation of primitive biopolymers. [1] As regard to the significance of N-phosphoryl amino acids as a model for the co-evolution of protein and nucleic acids at the prebiotic stage, [2] amphiphilic N-phosphoryl amino acids with two hydrophobic tails were synthesized. [3] 相似文献
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在B3LYP/6-31l++G(3df, 2pd)水平上全优化得到了三甲基铝双聚体(d-TMA)的C2h和C2v两种构型和单体的C3h结构. 着重用完全基组方法CBS-4M模拟计算了TMA气相平衡中各物种在1.01×105 Pa和300~550 K范围内的热力学函数值. 通过考察d-TMA三线态构型和异裂反应对系统熵值的影响, 准确计算了d-TMA离解反应的ΔrHm和ΔrSm. 以lnKd对1/T作图, 两者之间具有很好的线性关系: lnKd=−9624.4363/T+20.2303, 相关系数R2=1.0000, 与前人实验结果相当一致. 在此基础上提出了新的d-TMA气相离解-缔合反应机理. 相似文献
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A systematic quantum chemical characterization of intrinsic structure, energies and spectral properties of all the studied cross-link adducts formed by the novel trans platinum with thiazole ligand has been carried out at B3LYP/6-31G^* level of theory with the Lanl2dz pseudo potential basis set for the Pt atom. Special attention has been paid to the relative stability of these complexes and the factors that probably alter the order of the relative stability. The important influence of hydrogen bond on the structures, the energies and the spectral property was revealed. Other factors that contribute to relative stability including solvation effect, entropy and electronic delocalization energy were taken into account. The stability energy of the whole complex, and the interaction energy between two purine bases and the [Pt-(NH3)thiazole]^2+ group were adopted to study the interplay among subsystems and their contribution to relative stability of all the studied cross-link model. Finally, basic spectral properties of these complexes including H(8) chemical shifts of all the studied complexes and the VCD (vibrational circular dichroism) spectra of two pairs of GG chelate enantiomers, were provided in order to define the structure of the most possible duplex bearing novel trans platinum drug lesions. 相似文献