Synthesis and Structural Characterization of [Mn（sapn）（H2O）2]Br

1 INTRODUCTION Many of the recent advances in the coordination chemistry of manganese have been driven by the involvement of the manganese in several biological redox-active systems[1,2], of which the most important is the oxygen-evolving complex (EOC) of photosystem II (PS II) in green plants [3]. Since the preparations and structural characterizations of the complexes containing N,O-donor ligands have been studied extensively as simple active-site models for the photosystem II[4,5]…     

Controlled synthesis and magnetic properties of 2D and 3D iron azide networks infinity2[Fe(N3)2(4,4'-bpy)] and infinity3[Fe(N3)2(4,4'-bpy)

Controlled synthesis of transition metal complexes with mixed ligands has led to two new compounds with the same empirical formula [Fe(N3)2(4,4'-bpy)] (4,4'-bpy=4,4'- bipyridine). The compound 2D-[Fe(N3)2(4,4'-bpy)] (I) contains end-on (EO) bridging azido ligands. It crystallizes in the orthorhombic crystal system, space group Cmmm (No. 65): a=11.444(2) A, b=15.181(3) A, c=3.458(1) A, V=600.8(2) A(3), and Z=2. The compound 3D-[Fe(N3)2(4,4'-bpy)] (II) contains end-to-end (EE) azido bridges. It belongs to the tetragonal crystal system, space group P4(1)2(1)2 (No. 92): a=8.132(1) A, b=8.132(1) A, c=16.708(3) A, V=1104.9(5) A(3), and Z=4. Crystals of I and II have been grown by the diffusion method. Phase-pure samples of both compounds have been obtained by means of an optimal solution synthesis. Spontaneous long-range magnetic ordering was found in both I and II, with I being a metamagnet, and II being a ferromagnet. For I, in the low-field region, multiple transitions at TN1=20 K and TN2=5 K were observed, and these indicated the existence of Fe moment reorientation. Heat capacity measurements on II confirmed ferromagnetic transition at TC=20 K.     

细胞色素C在离子液体修饰电极上的电化学行为

分别合成了疏水和亲水性咪唑类离子液体,并制备了相应的两种离子液体修饰的玻碳电极。循环伏安法测量结果显示,细胞色素C在离子液体修饰的玻碳电极上的电子传递过程为一扩散控制的准可逆反应,表明咪唑类离子液体也可用作细胞色素C电子传递的有效促进剂。电化学交流阻抗谱的测量结果得到了与循环伏安相同的结论。     

Prokaryotic Expression and Polyclonal Antibody Preparation of PRL3

Phosphatase of regenerating liver 3(PRL3),which belongs to the superfamily of protein tyrosine phosphatases(PTPs),represents a group of low molecular weight PTPs that participate in tumorigenesis and metastasis processes.Presented here are the results of cloning,prokaryotic expression,purification,and polyclonal antibody preparation of PRL3.To obtain a specific polyclonal antibody against PRL3,the authors have prepared GST-PRL3 to immunize rabbits and purify an anti-PRL3 polyclonal antibody by negative selection affinity columns.Western blot analysis shows that the anti-PRL3 polyclonal antibody has a specific binding ability with PRL3 protein.The anti-PRL3 polyclonal antibody provides a good tool to further study the function of PRL3.     

高吸水树脂的溶胀动力学

基于扩散-松弛模型,分别研究了树脂粒度和溶液浓度对高吸水树脂溶胀行为的影响。实验结果表明:水分子的扩散和树脂大分子链段的松弛对树脂的溶胀均有贡献,但两者贡献大小与树脂粒度和溶液浓度有关。     

Electrochemical study of bergenin on a poly(4-(2-pyridylazo)-resorcinol) modified glassy carbon electrode and its determination in tablets and urine

A very sensitive electroanalytical method was employed to determine bergenin in phosphate buffer with a pH of 6.0, bergenin was accumulated at a 4-(2-pyridylazo)-resorcinol (PAR) polymer film modified glassy carbon electrode (GCE) surface under the condition of open-circuit. In the following anodic sweep from −0.4 to 0.8 V, bergenin adsorbed at the PAR polymer film modified electrode surface, was oxidized and yielded a sensitive oxidation peak at 0.595 V. Due to its unique structure and extraordinary properties, the PAR polymer film shows higher accumulation efficiency toward bergenin compared with a bare GCE. Hence, the amount of bergenin at the PAR polymer film modified GCE surface increases significantly, and finally the oxidation peak current improves greatly. The experimental conditions, such as supporting electrolyte, pH value, accumulation time and scan rate, were optimized for the measurement of bergenin, and a sensitive electroanalytical method was proposed for bergenin determination. The oxidation peak current varies linearly with the concentration of bergenin over the range of 2.0 × 10⁻⁷ to 1.2 × 10⁻⁵ mol/L, and the detection limit is 2.0 × 10⁻⁸ mol/L after 3 min open-circuit accumulation. The relative standard deviation of the same electrode in 10 successive scans is 1.8% for 1.0 × 10⁻⁶ mol/L bergenin and 2.1% for interelectrodes, indicating excellent reproducibility. This new method was successfully demonstrated with bergenin tablets and diluted urine.     

碳纳米管为基质对氨基酸的MALDI-FT MS分析

Twenty common amino acids have been analyzed successfully by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) using carbon nanotubes as matrix. From the spectra, little or no background interference or fragmentation of the analytes has been observed. This method was also applied to the analysis of amino acid mixture successfully. Carbon nanotubes have some features such as large surface area to disperse the analyte molecules sufficiently and prevent the sample aggregation and strong ultraviolet absorption to transfer energy easily to the analyte molecules. The present method has potential application for the rapid and sensitive analysis of amino acids and their mixture.     

铈、锂盐对铝阳极氧化膜的协同封闭作用

研究了铈、锂盐在铝阳极氧化膜封闭处理中的协同作用.场发射扫描电镜和X射线衍射谱对铈、锂盐协同封闭前后铝阳极氧化膜形貌和结构的研究结果表明，封闭后膜表面的孔洞消失，封闭产物分布均匀，封闭后膜仍然以非晶态形式存在.根据X射线光电子能谱的结果，封闭后的膜主要由含结晶水的Al2O3及铈、锂的混合氢氧化物组成，同时膜中还含有及封闭溶液组分中的一些阴离子.电化学阻抗谱的研究结果表明铈、锂盐协同封闭能够显著提高膜的耐蚀性能.在实验结果基础上，初步认为铈、锂盐封闭是通过生成结构紧密的封闭产物填充、覆盖膜孔，从而显著提高铝阳极氧化膜的耐蚀性能.     

N,N''''-二(N-对羧基苯基胺甲酰甲基)-N,N'',N''''-三乙酸二乙三胺与锌配合物的合成和晶体结构

合成了锌与配体N,N"-二(N-对羧基苯基胺甲酰甲基)-N,N',N"-三乙酸二乙三胺的配合物ZnH3L·4H2O(H5L= C28H33N5O12),通过元素分析,IR,UV-vis和热重分析对配合物进行了表征,并测定了该配合物的晶体结构.晶体属三斜晶系,P (?)空间群,晶胞参数a=0.8442(2)nm,b=1.0837(3)nm,c=1.9082(6)nm,α=104.052(5)°,β=94.624(5)°,γ= 93.093(5)°,Z=2.结构由直接法解出,最终偏离因子R1=0.0547,wR2=0.1306.锌与配体的一个酰胺氧原子、两个亚胺氮原子和两个羧基氧原子配位,形成畸变的三角双锥构型.配合物分子间通过氢键连接形成三维网状结构.     

A chemical sensor for the liquid-ordered phase

The mixing properties of exchangeable phospholipids, derived from 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine, with an exchangeable form of cholesterol have been used to monitor the transition from the liquid-disordered to the liquid-ordered phase in cholesterol-containing bilayers, made from 1,2-dipalmitoyl-sn-glycero-3-phosphocholine and 1,2-distearoyl-sn-glycero-3-phosphocholine, respectively.