溶胶-凝胶法制备铁酸盐超微粒子催化剂

采用溶胶－凝胶法制备了含Zn,Ni,Co的铁酸盐超微粒子催化剂，运用DTA－TG、IR、XRD以及BET比表面测试等手段对所制备的样品进行了表征。同时，考察了铁酸盐对二氧化碳选择性氧化乙苯制苯乙烯的催化性能。结果表明：制备的铁酸盐均为尖晶石型晶体，粒子的比表面积为31．9－36．3m^2/g，晶粒大小约为30－35nm，在由二氧化碳选择性氧化乙苯制苯乙烯的反应中表现出较好的催化活性。     

钙钛矿型La_((1 x)/2)Sr_((1-x)/2)Co_(1-x)Cu_xO_3催化CO氧化活性与表征

研究了钙钛矿型LaSrCoCu_xO_3催化剂对CO氧化反应的催化活性及其表面氧的催化作用．结果表明，x＝0．4的催化剂对CO氧化具有最高催化活性，常压及本实验条件下CO完全氧化的最低温度为168℃；催化剂均为氧缺陷化合物，吸附于表面晶格氧缺陷上的吸附氧是CO氧化反应的活性氧物种；并发现催化剂中存在有非常价态的C04 ，认为CO氧化反应是通过吸附氧调变Co3 和Co4 价态而进行．     

Influence of shell strength on shape transformation of micron-sized,monodisperse, hollow polymer particles

Micron-sized, monodisperse, non-spherical polymer particles with "rugby ball" and "red blood corpuscle"-like shapes were produced by seeded polymerization of the dispersion of (divinylbenzene/vinylbiphenyl/xylene)-swollen polystyrene particles prepared by utilizing the dynamic swelling method which the authors proposed in 1991. Their non-spherical shapes were based on buckling of the shell of the resultant hollow particles. In this article, the reversible shape transformation of the hollow composite polymer particle between spherical and such non-spherical shapes was studied in detail by controlling the shell strength. A part of the shell was buckled by external pressure which was caused by evaporation of xylene from the hollow when the shell had the tensile modulus below the critical value calculated from the pressure-buckling relationship of a spherical shell proposed by Uemura. The plasticization of the shell by a good solvent was one of key factors for the shape transformation.     

芳亚甲基丙二腈、芳亚甲基氰乙酰胺的固相合成

芳醛和丙二腈、氰乙酰胺在NH4Ac催化下经固相反应高产率的得到芳亚甲基丙 二腈和芳亚甲基氰乙酰胺。     

Facile cyclic ammonium salt with the smallest size for high performance electric double layer capacitors

A novel cyclic ammonium salt, N,N-dimethylpyrrolidinium tetrafluoroborate (P₁₁-BF₄), was successfully synthesized for the first time. The smallest cyclic structure of P₁₁-BF₄ induced high solubility and conductivity in PC, which can easier enter the micropores of activated carbon and occupy more surface area during charge/discharge process.     

Tree-gel and loop-gel conversions in nonlinear polymerization

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X-ray investigation of the role of the mixed emulsifier in the structure formation in o/w creams

The aim of this research work was to clarify the role of the mixed emulsifier in the structure formation and water binding mode in the case of o/w creams prepared with different surfactants. The swelling behavior of mixed emulsifiers was examined by means of direct investigation methods such as transmission electron microscopy (TEM) and X-ray diffraction. The detailed structure image of the creams was created with the help of the latter. The influence of the structure of the hydrophilic gel phase, and the structural changes during storage were studied with rheological methods. On the basis of the results, it can be stated that the investigated creams had different structures from those mentioned in the literature: surfactant did not create a mixed bilayer with the structure to furnish fatty amphiphile; instead, micelles were formed. These results correlated well with the results of the rheological tests.     

Use of SPE—TLC for Quality Control of Rhodiola rosea Extracts

SPE and TLC have been used for qualitative and quantitative analysis of salidroside, rosavin, rosarin, and rosin in commercially available dry extracts from Rhodiola rosea roots. The best separation of all the compounds was achieved on silica gel TLC plates with ethyl acetate—methanol—water, 77 + 13 + 10 (v/v), as mobile phase. UV detection was performed at λ = 215 nm for salidroside and at λ= 245 nm for the rosavins (rosavin, rosarin, and rosin). Detection limits for salidroside and the rosavins were 90 ng and 60 ng per spot, respectively. Results from quantitative analysis confirmed the manufacturer’s declaration of the amounts of salidroside and the rosavins in the extracts.

     

FT-IR and Raman spectroscopic study of hydrated rubidium (cesium) borates and alkali double borates

FT-IR and Raman spectra of five hydrated alkali borates and five hydrated alkali double borates have been recorded at room temperature in the range 400 to 4000 cm⁻¹, and analyzed. Fundamental vibrational modes have been identified and assignments tentatively made in comparison with the work of Janda and Heller, and Li Jun. The text was submitted by the authors in English.     

Selective dimerization of α-methylstyrene catalyzed by a solid acid

A novel solid acid prepared from concentrated sulfuric, boric and phosphoric acid is a highly selective catalyst for the dimerization of α-methylstyrene at room temperature to generate 4-methyl-2,4-diphenyl-1-pentene.