2,3-二羟基萘钼多酸有机衍生物的合成及1H NMR和IR谱学研究

本文对二种新合成的2，3－二羟基萘二钼和四钼多酸有机衍生物[n-Bu)4N]2[Mo2O5(OC10H6O)2](Ⅰ）和[n-Bu)4N]2[Mo4O10(OC10H6O)2(OCH3)2](Ⅱ)进行了红外光谱与核磁共振波谱研究，发现[Mo2O5]^2 中钼氧多桥键的红外振动频率较[Mo4O10(OCH3)2]^2 中钼氧多桥键的红外振动频率红移，而在配合物Ⅱ中2，3－二羟基中芳环的^1H化学位移较配合物Ⅰ中向低场移动。同时还发现含二钼配位中心[Mo2O5]^2 的[Mo2O5(OC10H6O)2]^2-与含四钼配位中心[Mo4O10(OCH3)2]^2 的[Mo4O10(OC10H6O)2(OCH3)2]^2-生成条件的差异仅仅只在反应体系的pH值的微小变化，说明钼多酸有机衍生物阴离子是对体系酸碱度极为敏感的物质。     

Human insulin and desamido human insulin isotherms in ethanol-water reversed phase systems

The multi-component isotherms for human insulin (HI) and desamido human insulin (dHI) over reversed phase packing (C18) and with 29.8% (w/w) ethanol-water as mobile phase have been determined experimentally. The isotherms of HI in ethanol-water differ from those obtained with the more commonly applied methanol-water and acetonitrile-water mobile phase, as described in this paper. The isotherm exhibits anti Langmuirian behavior and can be very well modeled by an anti Langmuir isotherm presented in this paper. The HI and dHI anti Langmuir isotherm are determined as: qHI = (8.4C(HI) + 3C(HI)CdHI)/(1 - 0.05C(HI) - 0.14CdHI + 0.04C(HI)CdHI) and qdHI = (11.4CdHI + 2C(HI)CdHI)/ (1 - 0.05C(HI) - 0.14CdHI + 0.04C(HI)CdHI)     

Arsenazo III and its analogues-V Complex formation of niobium with o,o'-dihydroxyazo compounds

A new group of reagents-the 2,7-bisazo derivatives of chromotropic acid-has been synthesized and the reaction of these compounds with niobium studied. Reaction with niobium occurs in strongly acidic medium (1-3N) and is characterized by high sensitivity ( = 30-50 x 10(3)). The functional grouping responsible for the reaction was shown to be the o,o'-dihydroxyazo group. The analytical usefulness of the reagents is determined by the presence of the electron-withdrawing substituents and the nature of the diazo coupling component. Niobium reacts in partially hydrolysed form with these reagents, to give 1:1 complexes.     

Membrane ion-exchange chromatography for process-scale antibody purification

Microemulsion electrokinetic chromatography (MEEKC) was evaluated as a screening tool for the indirect measurement of octanol–water partition coefficients (log P_o/w) of pesticide compounds. Over 80 pesticide compounds representing a variety of structural characteristics were studied, and good correlation of log P_o/w with the logarithm of the retention factor was found. The microemulsion system studied allowed the separation of compounds in the log P_o/w range of −1 to 7. In addition, a smaller set of simple organic molecules that vary in structural features was evaluated and compared to the pesticide log P_o/w calibration. The pesticide and simple organic molecule log P_o/w calibration lines were statistically similar. This suggests that a universal set of standard compounds may be employed for the log P_o/w calibration to provide measurements for a variety of compounds with good accuracy.