键连接性指数的建构及其在有机体系中的应用研究

以化学键为基础建构了键连接性指数及分子键连接性指数，该指数同时考虑顶 点原子的化学特征及键的性质．对于任意化学键，键连接性指数Si＝1+△I/R·[（ Z1-h1)m2/n1+(Z2-h2)m1/n2]，分子键连接性指数S为∑i=1^m√Si或∑i=1^m1/√ Si，其中，Z1，Z2为化学键键连原子的价电子数；n1，n2成键原子的价层最高主量 子数；m1，m2为成键原子的氧化数；h1，h2为与成键原子相连的氢原子个数；△I 为成键原子的电负性差(△I≥0)；R为化学键的相对键长．与以顶点为基础的价连 接性指数不同，该指数不仅能方便而有效地应用于饱和碳氢体系亦能有效地应用于 含多重键的不饱和体系及含杂原子的有机体系．研究了饱和碳氢体系标准生成焓， 不饱和碳氢体系和酮、醚、酯体系在水中的溶解度和辛醇/水分配系数，卤代甲烷 体系的标准生成焓，卤代苯体系辛醇/水分配系数，均取得比较满意的结果。     

Inorganic—Organic Hybrid 18—Molybdodiphosphate Nanoparticles Bullk—modified Carbon Paste Electrode and Its Electrocatalysis

A kind of inorganic‐organic hybrid 18‐molybdodiphosphate nanoparticles ([(C₄H₉)₄N]₆P₂Mo₁₈Q₆₂·4H₂O) was firstly used as a bulk‐modifier to fabricate a three‐dimensional chemically modified carbon paste electrode (CPE) by direct mixing. The electrochemical behavior of the solid nanoparticles dispersed in the CPE in acidic aqueous solution was characterized by cyclic and square‐wave voltammetry. The hybrid 18‐molybdodiphosphate nanoparticles bulk‐modified CPE (MNP‐CPE) displayed a high electrocatalytic activity towards the reduction of nitrite, bromate and hydrogen peroxide. The remarkable advantages of the MNP‐CPE over the traditional polyoxometalates‐modified electrodes are their excellent reproducibility of surface‐renewal and high stability owing to the insolubility of the hybrid 18‐molybdodiphosphate nanoparticles.     

Cluster Build-up Reactions using Di-gold Cationic Fragments: Synthesis and Structural Characterization of [Os7(CO)19(Au2dppm)]

The reaction of the di-gold cation [Au₂(dppx)]²⁺ with the heptanuclear cluster dianion [Os₇(CO)₂₀]^2– affords the mixed metal cluster [Os₇(CO)₂₀{Au₂(dppx)}] (x=m (1), e (2), b (3)). On standing, in solution, this complex undergoes decarbonylation to give the cluster [Os₇(CO)₁₉{Au₂(dppx)}] (x=m (4), e (5), b (6)). The complexes have been characterised spectroscopically, and an X-ray structure determination of the dppm derivative shows that it contains a metal core based on an Os₇ edge-bridged bicapped tetrahedron with the two ₃-Au atoms capping adjacent triangular Os₃ faces of the central tetrahedron. In an analogous reaction, the carbido anion [Os₇(H)C(CO)₁₉]^– affords the neutral cluster [Os₇C(CO)₁₉{Au₂(dppm)}] (7) when treated with [Au₂(dppm)]²⁺ in the presence of base.     

血清中Mo、Se、Mn、Cu、Zn与食管癌的关系探讨

通过对１８例食管癌患者以及８０例对照组血清中Ｍｏ、Ｓｅ、Ｍｎ、Ｃｕ、Ｚｎ的测定分析，发现食管瘤患者血硒含量明显低于对照组，二者之间有极显著性差异（Ｐ＜０．０１）。而血铜、铜／锌比值食管癌组明显高于对照组，差异有显著性（Ｐ＜０．０５）。Ｍｏ、Ｍｎ、Ｚｎ元素的含量在二组之间无显著性差异（Ｐ＞０．０５）．提示血清硒铜与食管癌有关。     

Metal Nanoparticles on Stainless Steel Surfaces as Novel Heterogeneous Catalysts

The goal of this work was the development of a novel type of heterogeneous catalyst, consisting of bare metal nanoparticles on stainless steel foils, which can be shaped to any kind of architecture and, if necessary, heated electrically. Solutions of pre-prepared, ligand protected and monodispersed gold, palladium, platinum and rhodium nanoparticles were sprayed onto stainless steel foils, followed by the careful removal of the ligand molecules by an oxygen plasma treatment. Due to this, bare particles become irreversibly fixed on the steel support. It could be shown that the original particle sizes do not change during the plasma treatment. Foils, densely coated with the nanoparticles, were used for gas phase catalyses in a self-made reactor at room temperature or at 60 °C. Hydrogenation of 1,3-butadiene at 15 nm Pd and 2 nm Pt, CO oxidation at 16 nm, 8 nm and 1.4 nm gold and NO reduction with NH₃ at 2 nm Rh particles were performed, indicating that the novel catalysts might in principle be applicable in technical processes if the experimental conditions like form and temperature would be optimized. Dedicated to Professor Dieter Fenske on the occassion of his 65th birthday.     

A new phase in the Ag−O−S system

The investigations of reaction between Ag₂SO₄ and Ag₂S in air atmosphere have been carried. Results of DTA and X-ray phase powder diffraction of a reaction mixture have confirmed that in the Ag?O?S system exists a new phase. A formula of the phase is Ag₂SO₂.     

Ga^3＋的新萃取体系的界面特性和胶团化作用研究

研究了Ｇａ~（３＋）协萃体系（Ｇａ~（３＋）－Ｄ_２ＥＨＰＡ－Ｈ_２ＭＰＡ－正十二烷－Ｈ_２ＳＯ_４）的界面吸附和胶团形成热力学，发现该萃取体系中［Ｈ_２ＭＰＡ］影响Ｄ_２ＥＨＰＡ和Ｈ_２ＭＰＡ的界面吸附性质。在中、高［Ｈ_２ＭＰＡ］范围内Ｄ_２ＥＨＰＡ与Ｈ_２ＭＰＡ的界面吸附行为相反，Ｄ_２ＥＨＰＡ的存在也影响Ｈ_２ＭＰＡ的界面吸附行为。研究了界面张力与各因素关系的数学模型，并获得某些胶团形成和界面吸附特性的物化参数。     

Gold nanoparticles as dehydrogenase mimicking nanozymes for estradiol degradation

Small gold nanoparticles can mimic dehydrogenase activity to catalyze estradiol (E2) oxidation to estrone (E1), extending the range of nanozyme catalysis to environmentally and biologically important substrates.     

Thermodynamic dissociation constants of salicylic and monochloroacetic acids in mixed solvent systems from conductance measurements at 25°C

The molar conductances of dilute solutions of salicylic and monochloroacetic acids in binary mixtures of methanol, ethanol, 1-propanol, N,N-dimethylformamide, acetone, acetonitrile, tetrahydrofuran and dioxane with water have been measured at 25°C. The Lee-Wheaton conductance equation was fitted to the data in order to derive thermodynamic dissociation constants and limiting molar conductances. The results were compared with those in the literature pertaining to analogous media, mostly derived potentiometrically. The findings are interpreted in terms of a solvent effect on the ionization of these acids in mixed solvent systems.This paper is dedicated to the late Professor Raymond M. Fuoss on his 3^rd anniversary.