STABILITY OF POLY（N,N＇-METHYLENEBISACRYLAMIDE-co-4-VINYLPYRIDINE） MICROGEL DISPERSION AND ADJUSTMENT OF THE HYDROPHOBICITY IN THE MICROGELS

In the UV-Vis spectra of pure light-scattering systems, there is an exponential relationship between absorbance and wavelength （A = Kλ^-n）. Here, the exponent n is named as flocculation-coagulation parameter. In the present paper, the effects of different additives on the stability of poly（N,N＇-methylenebisacrylamide-co-4-vinylpyridine） （poly（Bis-co-4-VP）） microgel dispersion were studied in detail via this parameter. The results showed that the stability of the dispersion mainly comes from the ionization of pyridine groups, making the microgel positively charged on its surface. This was confirmed by the measurement of Zeta potential and the result of conductometric titration. The result of fluorescence analysis indicated that the hydrophobicity in the microgels is enhanced with the increase in total 4-VP unit content.     

Analysis of Equilibrium and Kinetics of Chromium-Fluoride Complexation from Spectroscopic Data via Chemometrics Methods

IntroductionStudies on reversible kinetic systems are consi-dered as a hotspot of chemical and biochemical kineticresearches[1,2]. Of late, some researches have been fo-cused on the simultaneous optimization of the obverseand reverse rate constants[3,4].H…     

稀土-噻吩甲酰三氟丙酮-4,4′-联吡啶-N,N′-二氧化物三元配合物的合成与表征

首次合成了稀土－噻吩甲酰三氟丙酮（ＴＴＡ）－４，４′－联吡啶－Ｎ，Ｎ′－二氧化物的三元配合物，通过元素分析，确定其组成为：Ｌｎ（ＴＴＡ）３０．５（４，４′－ｂｉｐｙＮ２Ｏ２），通过紫外、红外以及热谱分析，讨论了它们的物理化学性质。     

二溴苯基萤光酮和金属离子显色反应的研究及其分析应用——Ⅰ锗(Ⅳ)——二溴苯基萤光酮——溴化十六烷基三甲铵显色体系

萤光酮类试剂对于多价阳离子具有较高的反应灵敏度,在某些表面活性剂或辅助络合配位体存在下可形成灵敏度更高的多元络合物。锗(Ⅳ)和苯基萤光酮的显色反应报导较多,其摩耳吸光系数一般是1.2-1.4×10~5。沈含熙等最近发表的水杨基萤光酮——溴化十六烷基三甲铵一锗(Ⅳ)显色反应体系的灵敏度达1.89×10~5。     

Rheological Behavior for Mica-filled Polypropylene Composite Melts

The study on rheological properties of a series of mica-filled polypropylene (PP) composites was carried out. The influence of surface-treatment of mica particles on dynamic rheological behavior of the composites were dealt with. The viscosity (η) and dynamic modulus ( G‘ ) of the composite melts were higher than those of PP matrix, especially those for systems treated with silane, which was attributed to the interfacial adhesion enhancement. However, surface-treatment of mica by titanate resulted in lower η and G‘, as compared with the treatment by silane. The reason for this is believed to be the formation of the mono-molecular layer on the mica surface.     

雨水中微量银的萃取无焰原子吸收光谱测定

碘化银人工增雨水样以及天然雨雪中微量银的无焰原子吸收测定通常要采用离子交换,二乙基二硫代氯氨基甲酸二乙铵溶于甲基异丁酮萃取,双硫腙——四氯化碳萃取,阴离子树脂分离后再用吡咯烷二硫代甲酸铵水溶液萃取,硫代磷酸三辛酯——甲基异丁酮萃取,再以盐酸反萃,吡咯烷二硫代甲酸铵水溶液——甲基异丁     

Fe-Zn二元金属氧化物在高温燃气脱硫过程中的互补协同效应

采用~(57)Fe M(?)ssbauer谱学方法,跟踪考察新一代Fe-Zn二元金属氧化物脱硫剂在高温燃气脱硫过程中的相态变化.结果表明,该脱硫剂在高温燃气中迅速还原,分解析出活性脱硫组分——高分散微晶态零价铁和氧化锌新相.前者承担提高硫容的粗脱硫功能,后者承担提高净化度的精细深度脱硫功能,两者存在互补协同效应.     

A New Approach to α—Bromochalcones

α-Bromo benzolymethylene triphenylphosphorane 3 has been synthesized by the reaction of benzoylmethylene triphenylphosphorane 1 with N-bromosuccinimide in the yield of 87% and can react with aromatic aldehydes 4 to give α-bromochalcones 5 in good yields.