Synthesis of 1‐Aryl‐1H‐indazoles via a Ligand‐Free Copper‐ Catalyzed Intramolecular Amination Reaction

A general synthesis of 1‐aryl‐1‐H‐indazoles from o‐halogenated aryl aldehydes or ketones and aryl hydrazines was described. This protocol included an intermolecular condensation and a ligand‐free copper‐catalyzed intramolecular Ullmann‐type coupling reaction. This method was applied to a wide range of substrates to produce the indazole products in good yields.     

Low-temperature activation of methane over rare earth metals promoted Zn/HZSM-5 zeolite catalysts in the presence of ethylene

At low temperature of 723 K, methane can be easily activated in the presence of ethylene in the feed, and converted to higher hydrocarbons (C2–C4) and aromatics (C6–C10), through its reaction over rare metals modified Zn/HZSM-5 zeolite catalysts without undesirable carbon oxides formation. Methane can get 37.3% conversion over the above catalysts under low temperature, and the catalysts show a longer lifetime than usual metal supported HZSM-5 zeolite catalysts without adding any rare earth metals. The effects of methane activation over various rare earth metal promoted Zn/HZSM-5 catalysts on the products and influences of several reaction conditions such as temperature, catalyst lifetime and molar ratio of CH4/C2H4 have been discussed.     

壳聚糖对酸性艳橙GS的吸附平衡与动力学研究

研究了壳聚糖(CS)对水溶液中的酸性艳橙GS(ABO)染料的吸附性能,考察了温度、pH值、壳聚糖分子量对吸附性能的影响.不同温度下的动力学数据分别采用拟一级、拟二级、内扩散方程进行关联;不同温度下壳聚糖对酸性艳橙GS的吸附平衡数据分别用1angmuir、Freundlich、Tempkin模型拟合.结果表明:该吸附过程...     

Two new compounds with microporous constructed by Waugh-type polyoxoanion and transition metal ions

Two new compounds with microporous Co3[MnMo9O32].15H2O(1) and Cu3[MnMo9O32].15H2O(2) have been synthesized,and characterized by IR,element analysis,TG and single-crystal X-ray analysis.The structure analyses reveal that compounds 1 and 2 are isostructural.In crystal,the Waugh-type polyoxoanions [MnMo9O32]6-are connected by Co2+ or Cu2+ cations to a 3D open-framework,which possesses channels along the [1 2 2] direction of approximately 8.27 × 11.97 .The photocatalytic performances of compounds 1 and 2 for p...     

电化学振荡反应在中药鉴定中的应用

介绍化学振荡的由来、特点以及化学振荡理论研究、化学振荡在中药鉴定中的应用进展及未来发展趋势.深化研究化学振荡机理可以建立中药新型的准确、快速、方便的质量评价体系,推动中药在国际市场的发展.     

液相色谱串联质谱法测定养殖水体中孔雀石绿及其代谢物

研究利用液相色谱-串联质谱(LC-ESI-MS/MS)测定水产品养殖水体中孔雀石绿及其代谢物隐性孔雀石绿的方法.通过一系列实验对样品前处理条件进行了优化研究,养殖水样经乙酸酸化,净化后,采用HPLC-ESI-MS/MS检测分析.在多反应监测模式(MRM)下,外标法定量,定量限均为0.5μg/kg.在0.5～50μg/L...     

Synthesis of copolymers of poly(ether sulfone ether ketone ketone) and poly(ether ketone diphenyl ketone ether ketone ketone) by electrophilic Friedel–Crafts solution polycondensation

A new monomer, 4,4′‐bis(4‐phenoxybenzoyl)diphenyl(BPOBDP), was synthesized via a two‐step synthetic procedure. A series of novel poly(ether sulfone ether ketone ketone)/poly(ether ketone diphenyl ketone ether ketone ketone) copolymers were prepared by electrophilic Friedel–Crafts solution copolycondensation of isophthaloyl chloride (IPC) with a mixture of 4,4′‐diphenoxydiphenylsulfone (DPODPS) and 4,4′‐bis(4‐phenoxybenzoyl)diphenyl (BPOBDP), in the presence of anhydrous aluminum chloride and N‐methylpyrrolidone (NMP) in 1,2‐dichloroethane (DCE). The copolymers with 10–50 mol% DPODPS are semicrystalline and have remarkably increased T_gs over commercially available PEEK and PEKK. The copolymers with 40–50 mol% DPODPS had not only high T_gs of 170–172°C, but also moderate T_ms of 326–333°C, which are extremely suitable for melt processing. These copolymers have tensile strengths of 96.5–108.1 MPa, Young's moduli of 1.98–3.05 GPa, and elongations at break of 13–26% and exhibit excellent thermal stability and good resistance to acidity, alkali, and common organic solvents. Copyright © 2009 John Wiley & Sons, Ltd.     

Glucose Biosensor Using Glucose Oxidase and Electrospun Mn2O3‐Ag Nanofibers

The highly porous Mn₂O₃‐Ag nanofibers were fabricated by a facile two‐step procedure (electrospinning and calcination). The structure and composition of the Mn₂O₃‐Ag nanofibers were characterized by SEM, TEM, XRD, EDX and SAED. The as‐prepared Mn₂O₃‐Ag nanofibers were then employed as the immobilization matrix for glucose oxidase (GOD) to construct an amperometric glucose biosensor. The biosensor shows fast response to glucose, high sensitivity (40.60 µA mM^?1 cm^?2), low detection limit (1.73 µM at S/N=3), low K_m,app value and excellent selectivity. These results indicate that the novel Mn₂O₃‐Ag nanfibers‐GOD composite has great potential application in oxygen‐reduction based glucose biosensing.     

Anti-fatigue activity of extracts of stem bark from Acanthopanax senticosus

In the present study, we investigated the anti-fatigue activity in male Kunming mice of extracts of stem bark from Acanthopanax senticosus (ASSE) using a forced swimming test. Mice were divided into four groups (three ASSE administered groups and the control group). The control group were gavaged with distilled water and ASSE administered groups were gavaged with ASSE (100, 200 and 400 mg/kg). After four weeks, a forced swimming test was performed and the biochemical parameters related to fatigue were examined. The results suggested that ASSE could extend the swimming time to exhaustion of the mice, as well as increase the tissue glycogen contents, while decreasing the blood lactate and serum urea nitrogen contents. This indicated that ASSE had anti-fatigue activity and could elevate the exercise tolerance.     

Phenazinolins A-E: novel diphenazines from a tin mine tailings-derived Streptomyces species

Phenazinolins A-E (1-5), which possess a carbon skeleton unique to diphenazines (the azabicyclo[3.3.1]nonadienol moiety in 1-3 and the oxabicyclo[3.3.1]nonadienol moiety in 4 and 5), were isolated from tin mine tailings-derived Streptomyces diastaticus YIM DT26, with 1-3 exhibited appreciable cytotoxicity and antibiotic effects.