Unprecedented double C-C bond cleavage of a cyclopentadienyl ligand

Double C-C bond cleavage of a cyclopentadienyl ligand proceeded to titanacyclopentadienes when 2 equiv of nitriles were added and the resulting two-carbon unit and three-carbon unit were converted into a benzene derivative and a pyridine derivative, respectively, in one-pot.     

大黄素的吸附溶出伏安研究

研究了大黄素在甲醇、二氧六环和水的混合溶剂中以１％硼砂为支持电解质在静汞电极上的吸附伏安行为。建立了用微分脉冲吸附溶出伏安法测定其含量的新方法。在－０３０Ｖ（ｖｓＡｇ／ＡｇＣｌ）电位下吸附富集，可得一灵敏的还原溶出峰，峰电位－０７５Ｖ，浓度在５×１０－８～５×１０－９ｍｏｌ／Ｌ范围内与峰电流具有良好的线性关系，最低检出限为１×１０－９ｍｏｌ／Ｌ。该法用于含有大黄素体系的测定简便、快速、可靠。     

Matrix Effects and Behaviors of Elements in Oxalic Acid Medium by Inductively Coupled Plasma Mass Spectrometry

Because of its high sensitivity, wide dynamic range and relative freedom from interferences, inductively coupled plasma mass spectrometry (ICP-MS) has been developed for the determination of trace and ultra-trace levels of elements in various fields1. Due…     

堆积模型及其应用 Ⅰ.三氯化镧尿素配合物[LaCl_2(urea)_6]·Cl分子结构的推测与测定

镧系元素具有形成高配位数的特点,但由简单配位形成的多面体,最高配位数只能达到九,例如,[Ln(H_2O)_9]~(+[2])。有些从化学式来看符合九配位的化合物,如LnCl_3(H_2O)_6实际结构是八配位[LnCl_2(H_2O)_6]~(+[3])或六配位[LnCl_3(H_2O)_3]·3H_2O~[4])。这种情况促使我们对另一系列化合物LnCl_3(urea)_6~[5]产生兴趣。我们根据堆积模型推测LaCl_3(urea)_6的实际结构应当是[LaCl_2(urea)_6]~+Cl~-(见图1、2)。培养了这一化合物的单晶,进行了结构测定。本文报道有关结果。     

天花粉蛋白化学 Ⅳ.天花粉蛋白的基本一级结构

前文报道从我国民间用于引产的中草药天花粉中提取到活性组分结晶天花粉蛋白和它的物理化学性质,N-端氨基酸顺序的测定及其溴化氰降解碎片CBa的顺序分析. 天花粉蛋白是一个由224个氨基酸残基组成的单一肽链的简单蛋白质,其N-末端残基为Asp,C-端顺序经羧肽酶A测定,并结合其水解动力学的计算机拟合为     

羟基化合物及其葡醛酸苷化学结构与RP—HPLC保留行为相关性研究

采用体外孵育生物合成方法获得羟基化合物葡醛酸苷系列化合物，并对其反相高效液相色谱保留行为及底物与其葡醛酸结合物保留行为相关性进行了研究，建立了相应的结构－色谱保留行为相关性方程及葡醛酸苷类代谢物保留行为的预测方法。将ＱＳＲＲ研究扩展到药物代谢物领域，对药物Ⅱ相葡醛酸化代谢产物的ＨＰＬＣ分析提供了帮助。     

耐热细菌

多数酶是不喜高温的。众所周知,发酵可以在室温下进行,需要能量很少。但是温度升高有利于加快化学反应速度。因此,人们一直在研究耐热微生物,亦即含有可以在较高温度下进行化学反应的酶的菌种。美国农业部北部研究中心(Northern Regional ResearchCenter of the U.S.Department of Agriculture)已经找     

A Novel High Active TiO2/AC Composite Photocatalyst Prepared by Acid Catalyzed Hydrothermal Method

A high active novel TiO2/AC composite photocatalyst was prepared and used for phenol degradation. It was much more active than P-25 and exhibiting good decantability, less deactivation after several runs and less sensitive to pH change. Diffuse reflectance spectra (DRS) revealed that the electronic change in TiO2 did not occur by the addition of AC. Results of SEM and XRD suggested that better TiO2 distribution can be achieved when optimal AC content was adopted. The performance of the prepared TiO2/5AC catalyst revealed great practical potential in wastewater treatment field.     

Microwave-prompted Rapid and Efficient Synthesis of Diacyl Thiosemicarbazides and Semicarbazides in Solvent and Catalyst Free Condition

Eighteen 1-aroyl-4-（2-iodobenzoyl）thiosemicarbazides and corresponding semicarbazides were synthesized in excellent yield under microwave irradiation in solvent and catalyst free condition.