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1.
硫醇的分子连接性指数与气相色谱保留值   总被引:1,自引:0,他引:1  
硫醇的分子连接性指数与气相色谱保留值赵邦屯王利亚(洛阳师专化学系洛阳471022)关键词硫醇分子连接性指数气相色谱保留值中图分类号O657.71有机化合物的色谱保留行为与其结构之间的定量关系研究一直是物理化学、分析化学和生物化学的研究对象之一。长期以...  相似文献   
2.
采用平衡电负性和相对化学键长对传统距离矩阵进行修正,构建新拓扑指数Nt。结合路径数,建立碳氢化合物、醛、酮和硫醇等化合物在24种极性和非极性色谱柱上的定量结构-色谱保留指数关系(QSRR)模型,23种模型的相关系数大于0.99。模型经留n法交叉检验,显示出良好稳健性和预测能力。模型物理意义明确,表明色谱保留指数可用分子的大小、平衡电负性、支化度和形状等内在结构信息进行有效表征。模型经Needham公式分析,结果显示新指数Nt对保留指数影响最大。借助Hyperchem软件进行对比研究,结果表明拓扑化学法优于量子化学AM1法。  相似文献   
3.
The glassy carbon electrode was modified with a nickel pentacyanonitrosylferrate film by electrodeposition of Ni and subsequent derivatization with NaPCNF. The film was characterized by XPS and electrochemical methods. Cyclic voltammetry of the NiPCNF onto the GC shows a redox couple (FeIII/FeII) with E°′ of 538 mV (Ipa/Ipc around 1) and ΔEp of 93 mV in 0.5 mol L?1 KNO3, with a diffusion‐controlled process. There was a decrease of anodic peak currents of the film in the presence of sulfide and 2‐propanethiol due to a precipitation reaction on the film surface by nucleophilic attack.  相似文献   
4.
Chemical investigations on the acetone extract of the Formosan soft coral Nephthea erecta have afforded a new calamenene-type sesquiterpene with a mercaptan group at C-15, erectathiol (1), and a previously reported sesquiterpenoid, (+)-trans-calamenene (2). A novel sec-germacrane sesquiterpene (3), along with a novel norergosterol, chabrosterol (4), possessing a 19-norergostane skeleton, was isolated from the other soft coral Nephthea chabroli. The structures of these metabolites were elucidated through extensive spectroscopic analyses. In vitro anti-inflammatory activity of 1 and 4 (10 μM) significantly reduced the levels of the iNOS protein (58.0 ± 6.5% and 12.4 ± 2.9%) and COX-2 protein (108.7 ± 4.5% and 45.2 ± 5.4%). In addition, metabolite 1 (166 μg/disk) exhibited antimicrobial activities against a small panel of bacterial strains.  相似文献   
5.
以水滑石焙烧而成的Mg-Al复合氧化物(Mg(A1)O)固体碱负载磺化酞菁钴(CoPcTS)双功能催化剂催化1-辛硫醇氧化反应,具有与含10%NaOH的传统催化体系相似的催化性能,能有效地将1-辛硫醇氧化为二硫化合物.催化剂在循环使用时,活性下降,可能与CoPcTS氧化中心聚集有关.  相似文献   
6.
利用3,6-二氧杂-1,8-辛二硫醇(H2L)和HgCl2反应,得到组成为Hg3L2Cl2的配合物。制备了Hg3L2Cl2修饰的碳糊电极,研究了在1mol/L KCl水溶液中的循环伏安行为。研究结果表明在1mol/L KCl介质中,在0.3~-0.8V(vs.SCE)范围内出现Hg3L2Cl2的还原和L^2-在汞膜表面的吸附,在一0.30—0.30V范围内出现汞膜的氧化还原反应。  相似文献   
7.
The vibrational analysis of allyl mercaptan has vener been published. There are two internal rotors, the SH group and the CH2SH group, in the allyl mercaptan molecule. As in the case of propylene (1), the molecule has only one plane of symmetry (Cs point group) in its most symmetrical configuration (when the thiol group lies in the plane of the vinyl group). However, microwave studies have shown that it exhibits C1 symmetry (2). The infrared and Raman spectra of allyl mercaptan have been investigated in this study. The assignment of its fundamental modes has been made based on C1 symmetry of the molecule.  相似文献   
8.
In 2004, we started to develop a group contribution method aimed at estimating the temperature dependent binary interaction parameters (kij(T)) for the widely used Peng–Robinson equation of state (EOS). This model was called PPR78 (predictive 1978, Peng–Robinson EOS) because it relies on the Peng–Robinson EOS as published by Peng and Robinson in 1978 and because the addition of a group contribution method to estimate the kij makes it predictive. In our previous papers, 14 groups were defined: CH3, CH2, CH, C, CH4 (methane), C2H6 (ethane), CHaro, Caro, Cfused aromatic rings, CH2,cyclic, CHcyclicCcyclic, CO2, N2, and H2S. It was thus possible to estimate the kij for any mixture containing alkanes, aromatics, naphthenes, CO2, N2, and H2S whatever the temperature. In this study, the PPR78 model is extended to systems containing thiols (also called mercaptans). To do so, the sulfhydryl group: –SH was added.  相似文献   
9.
陆克平  朱培德 《分析化学》2006,34(11):1661-1664
把玻璃参比电极、环状的银-硫化银指示电极、以及铂丝屏蔽电极组合形成新型硫醇硫组合电极,研究了在含有0.2 mol/L硫离子的醇-水-氨介质中,在表面活性剂存在下,以环状银电极为阳极,恒定微电流电沉积的方式制备硫化银敏感层的条件。由此法制得的新型硫醇硫组合电极在Ag 浓度为1.0×10-1~1.0×10-5mol/L范围内斜率为59.0±0.5 mV/pC,测量下限为2.2×10-6mol/L,与同类商品电极相比,响应速度快、记忆效应小、重复性好、电位稳定,易于批量生产,具有较强的适应性和应用价值。  相似文献   
10.
Refinery spent-sulfidic caustic, containing only inorganic sulfides, has previously been shown to be amenable to biotreatment withThiobacillus denitrificans strain F with complete oxidation of sulfides to sulfate. However, many spent caustics contain mercaptans that cannot be metabolized by this strict autotroph. An aerobic enrichment culture was developed from mixedThiobacilli and activated sludge that was capable of simultaneous oxidation of inorganic sulfide and mercaptans using hydrogen sulfide (H2S) and methylmercaptan (MeSH) gas feeds used to simulate the inorganic and organic sulfur of a spent-sulfidic caustic. The enrichment culture was also capable of biotreatment of an actual mercaptancontaining, spent-sulfidic caustic but at lower rates than predicted by operation on MeSH and H2S fed to the culture in the gas phase, indicating that the caustic contained other inhibitory components.  相似文献   
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