Speciation analysis of aluminium(III) in natural waters and biological fluids by complexing with various catechols followed by differential pulse voltammetry detection

The biological effects of aluminium have received much attention in recent years. Speciation of Al is of basic relevance as it concerns its reactivity and bioavailability. A differential pulse voltammetry (DPV) procedure is proposed for speciation analysis of Al(III) in natural waters and biological fluids using six catechols (L-dopa, dopamine, epinephrine, norepinephrine, caffeic acid and o-benzenediol) as electroactive ligands. The decrease of the DPV anodic peak current for each catechol ligand is linear with the increase of Al concentration. This speciation analysis idea is based on the measurement of the complexation capacity, namely, different affinities of Al(III) for catechols and organic ligands under two pH conditions. The labile monomeric Al fraction (mainly inorganic aluminium) is determined at pH 4.6, while the total monomeric Al fraction is determined at pH 8.5. The principle for Al(III) speciation analysis by an electrochemical method is discussed. This sensitive and simple fractionation method is successfully applied to the speciation analysis of Al in natural waters and the results agree well with those of Driscoll's method. The speciation analysis of Al in biological fluids is also explored and the results are compared with those obtained by ultrafiltration and dialysis. Compared with other speciation protocols the electrochemical method possesses some remarkable advantages: rapidity, high sensitivity, cheap instrumentation and a simple operation procedure.     

FFC-1离子交换纤维物理化学性能的研究

利用扫描电镜、热失重-红外、元素分析、低温氮吸附等技术和化学手段对聚羧酸基FFC-1离子交换纤维的结构与性能特点等进行了系统研究．结果表明：FFC-1离子交换纤维为含适量酰肼类交联键的聚羧酸(钠)型离子交换材料，外比表面积大和传质距离短是其反应动力学性能优异的主要原因，FFC-1纤维具有良好的化学与热稳定性。在5mol/L硫酸、硝酸、盐酸和2mol／L氢氧化钠溶液中浸泡，交换容量未见明显降低。但过氧化氢溶液对其功能基有明显破坏，CO2为FFC-1纤维在高温区间(300℃～350℃)的主要分解产物。     

FFC-1离子交换纤维对酸碱有害气体吸附性能的研究

系统考察了不同直径及反离子形式的FFC-1聚羧酸离子交换纤维对酸碱有害气体的穿透吸附,各种温、湿度条件下的吸水率,以及作为有害气体吸附滤除材料的重复使用与再生性能。研究表明:FFC-1纤维直径的减小有利于提高对有害气体的动态吸附容量。在体系温度、相对湿度分别为15℃、50%时,以3D腈纶为起始原料的钠型FFC-1离子交换纤维的吸水率≥350mg/g.纤维;对SO2的穿透吸附容量可达200mg/g.纤维。FFC-1离子交换纤维具有良好的重复使用与再生能力,经20次再生循环使用后,纤维交换容量未见明显变化。     

卟啉作为信号传递介质的紫外可见光谱研究

合成了6种氨基酸水杨醛席夫碱(Sal-AA)：Sal-Gly(甘氨酸)、Sal-Phe(苯丙氨酸)、Sal-Arg(精氨酸)、Sal-Tyr(酪氨酸)、Sal-Met(甲硫氨酸)、Sal-Glu(谷氨酸)及其金属铜配合物。并分别在2种不同介质(三氯甲烷和甲醇)中，与四苯基卟啉TPP进行反应，研究了其紫外可见光谱性质，讨论了卟啉作为人工信号转导体系的传递介质，与氨基酸水杨醛席夫碱铜配合物的反应中，实现信号分子铜离子进一步传递的可能性以及溶剂对该信号传递的影响。结果表明，在三氯甲烷为溶剂时，除了Sal-Met的铜配合物之外，其余均能被TPP夺取而形成Metal TPP。而在以甲醇为溶剂时，只有Sal-Gly的铜配合物能被TPP所夺取。     

非线型缩聚物的重均分子量

本文用数学期望方法研究了非线型共缩聚物的重均分子量,并推导出重均分子量表达式,将3种特例的理论曲线与实验结果相比较,两者基本相符。     

一维链状锰配位聚合物[Mn(4-CPOA)(2,2-bipy)(H_2O)]_n的合成与晶体结构(英文)

0IntroductionThe solid-state chemistry of manganese!car-boxylate coordination polymers has received growingattention over the past few years,owing to their fasci-nating network topologies and potential application inthe field of molecular magnetism and bi…     

Chemical Constituents from Cynoglossum gansuense

Two new alkaloids, i.e., (2,3‐dihydro‐1‐oxo‐1H‐pyrrolo[1,2‐a]pyrrol‐7‐yl)methyl (2S*,3S*)‐3‐[(β‐D ‐glucopyranosyl)oxy]‐2‐hydroxy‐2‐(1‐methylethyl)butanoate ( 1 ) and 1,2‐dihydro‐8‐methoxy‐2‐oxoquinoline‐4‐carboxylic acid ( 2 ), were isolated from the alcoholic extract of the whole plant of Cynoglossum gansuense, together with twelve known compounds Their structures were characterized by means of spectroscopic methods, especially by ¹H‐, ¹³C‐, and 2D‐NMR, as well as by HR‐MS experiments and comparison with literature data.     

反相高效液相色谱法测定3种中成药中的葛根素

 建立了测定小儿清感灵片、步长新脑心通胶囊和感冒清热颗粒 3种中成药中葛根素含量的反相高效液相色谱方法。采用APEXODS色谱柱 ,以醋酸铵缓冲液 (10 0mmol/L ,pH 5 0 ) 甲醇 (体积比为 75∶2 5 )的混合溶液为流动相 ,检测波长为 2 5 0nm ,流速为 0 8mL/min。葛根素在 2mg/L～ 2 0mg/L时其色谱峰面积与质量浓度的线性关系良好 (r =0 9999) ;上述 3种中成药中的葛根素含量分别为 3 48mg/g ,1 0 8mg/ g及 1 5 2mg/ g(蔗糖型 ) ;其加样回收率分别为 99 0 % ,93 4%和 97 5 %。该法简便、快速、专属性强 ,可以作为多种中药制剂中葛根素含量的测定方法。     

高稳定性CaO-ZrO2固体碱催化剂的表征和催化性能

用共沉淀法经高温焙烧制备了CaO摩尔分数从10%至50%的CaO-ZrO₂系列催化剂, 将其应用于碳酸丙烯酯和甲醇酯交换合成碳酸二甲酯过程, 并通过XRD, FT-IR, BET, ICP, CO₂-TPD, XPS等表征手段研究了催化剂的物性及其催化性能随组成变化的的规律. 结果表明, 当CaO摩尔分数高于30%时, 表面出现游离的CaO, 虽然具有强碱性和高活性, 但是稳定性差; 而当CaO摩尔分数低于30%时, Ca^2＋进入ZrO₂晶格, CaO与ZrO₂形成连续固溶体, 并且随着CaO含量的增加, 晶格氧的电荷密度增加, 催化剂的碱性增强, 使得CaO-ZrO₂催化剂在碳酸丙烯酯和甲醇酯交换合成碳酸二甲酯过程中获得了高活性和高稳定性.     

铁轴草中Teucvidin的衍生物研究

从唇形科植物铁轴草中分离得去甲克罗烷二萜化合物Ｔｅｕｃｖｉｄｉｎ，通过催化氢化、酯交换、水解等反应合成了８个衍生物，用＾１ＨＮＭＲ、ＭＳ和ＩＲ确定了其结构，初步生物活性测定结果表明，化合物Ⅱ和Ⅳａ的拒食作用显著。