Synthesis and Crystal Structure of aNovelPolythiotungstate Compound[PPh4]2[（S）2W（μ—S）2（O）W（THF）（μ—S）2W（S）2]

1 INTRODUCTION Polythiotungstate complexes can be prepared from the protonation of one sulfur atom of [WS4]2－ and subsequent intramolecular redox reactions[1,2]. For example, [(S)2W(m-S)2W(m-S)2W(S)2]2 was formed by the acidification of a diluted aqueous solution of (NH4)2[WS4] with dilute H2SO4[3]. When a diluted aqueous solution containing [WS4]2 was acidified with 0.1mol/L HCl, [(S)2W(m-S)2(O)- W(H2O)(m-S)2W(S)2]2 was formed[4]. [(S)2W- (m-S)2(S)W(m-S)2W(S)2]2 was form…     

一维链钴配位聚合物{[Co(H2O)4(3,3′-azpy)](3,3′-azpy)3(PF6)2}n的结构和性质的研究

The complex {[Co(H₂O)₄(3,3′-azpy)](3,3′-azpy)₃(PF₆)₂}_n(3,3′-azpy=3,3′-azobispyridine) has been synthesized and characterized. The crystal (C₄₀H₄₀F₁₂CoN₁₆O₄P₂, M_r=1157.75) belongs to the triclinic system, space group P1 with the following crystallographic parameters: a=10.759(2),b=11.012(2), c=23.207(4)?; α=85.330(10), β=83.470(10),γ=69.770(10)°;V=2560.6(8)?³,D_c=1.502g·cm^-3, μ(MoKα)= 0.498mm^-1,F(000)=1178,Z=2, and final R₁=0.0469, wR₂=0.1053 for observed reflections 5549 (I> 2.00σ(I)).The X-ray analysis reveals that cobalt(Ⅱ) cation coordination environment is a distorted octahedral geometry, the Co²⁺ ion is coordinated by four oxygen atoms of water in the equatorial plane, while the two nitrogen atoms of 3,3′-azpy occupy the axial positions. The complex forms a one-dimensional chain structure via 3,3′-azpy bridging ligand. The one-dimensional chain forms three-dimensional network by hydrogen bonds and π-π inter-actions.     

Synthesis and Crystal Structure of N,N''''-Dimethyldithio-arbamato-Copper(I) Polymer {[Cu(Me_2dtc)]_2}_n

Introduction In recent years, metal dithiocarbamate complexesremain attractive because of their possible relevance tothe nature of the sulfur-metal bond in some bimole-cules1 and their potential biological role in anti-alkyla-tion and cancer disease treatment.2 Among them, cop-per(II) dithiocarbamate complexes have been exten-sively investigated due to their rich structural magnetic,and electrochemical properties.3 However, the chemistryof copper(I) complexes of dithiocarbamates seems lesse…     

新型官能团化聚己内酯的研究进展

聚己内酯(PCL)是一种具有良好药物透过性的可生物降解的脂肪族聚酯,是一类优良的药物载体.由于其结晶性强,亲水性差,生物降解速度慢,限制了其在组织工程等生物医用领域更广泛的临床应用.在PCL主链上引入功能性官能团既可有效地降低其结晶性、改善其亲水性、调控其降解速率,同时又可通过反应性官能团进行进一步的化学改性或生物活性化修饰,已成为生物可降解材料新的研究热点.本文综述了含侧基官能团己内酯单体的合成及其聚合反应,简要介绍了侧基官能团对聚己内酯性能的影响.     

[WS3Cu2]簇基超分子框的组装、结构及其三阶非线性光学响应

将二(4-吡啶)硫烷(L₁)、4，4''-二(4-吡啶)二苯甲酮(L₂)分别与(Et₄N)(Tp*WS₃)(A)(Tp*=三(3，5-二甲基吡唑)氢合硼酸根)和[Cu (MeCN)₄]PF₆进行反应，得到2个W/Cu/S簇基超分子化合物[Tp*WS₃Cu₂(L₁)]₂(PF6)2·2MeCN·2CHCl₃(1·2MeCN·2CHCl₃)和[Tp*WS₃Cu₂(L₂)(MeCN)]₂(PF₆)₂·4MeCN (2·4MeCN)。对配合物1·2MeCN·2CHCl₃和2·4MeCN分别进行了单晶X射线衍射、核磁、质谱、红外、紫外可见和元素分析表征。单晶X射线衍射分析表明，它们是由2个L₁/L₂配体连接2个[Tp*WS₃Cu₂]⁺簇核形成的阳离子型簇基超分子框。核磁氢谱和高分辨电喷雾离子化质谱(HRESI-MS)证明它们在溶液中具有一定的稳定性。并利用Z扫描技术测试了超分子化合物1·2MeCN·2CHCl₃和2·4MeCN溶液的三阶非线性光学特性，测试结果表明它们的三阶非线性光学响应强于前驱体A。     

Observation of Three-Quasiparticle Doublet Bands in ^123I： Possible Evidence of Chirality

A new band in the odd proton nucleus ^123I is identified via in-beam γ-ray spectroscopy using the ^14N＋^116Cd reaction. This band shows up as doublets with the previously assigned π97/2 （vh11/2）^2 band. Possible configurations of the new band are discussed in the framework of the cranked shell model and the geometrical model It is argued that the new band might be a chiral partner of the previously known πg9/2 （vh11/2）2 band.     

氧化石墨烯/PMMA和表面官能化的石墨烯/PMMA复合材料的制备及其力学性能的研究

使用简单的溶液共混的方法制备了氧化石墨烯/聚甲基丙烯酸甲酯(GO/PMMA)和表面官能化的石墨烯/聚甲基丙烯酸甲酯复合材料.通过透射电镜(TEM),扫描电镜(SEM)和原子力显微镜(AFM)观察了石墨烯及复合材料的表观形貌.通过拉伸实验表征了其力学性能,研究发现随着石墨烯的加入,其拉伸强度和断裂伸长率都有所改善,而且表面官能化的石墨烯的复合材料的改善效果要优于氧化石墨烯.     

氢化物发生原子荧光法测定稻田土中的锑形态

采用王水消解及逐级浸提技术,以氢化物发生-原子荧光法对成都东郊稻田土中的Sb形态进行了分析,方法检出限为0.108μg/L,回收率为96.9%～104.8%。加入硫脲-抗坏血酸溶液后,土壤样品中可能存在的金属离子Cu2+、Co2+、Se4+、Sn2+、Zn2+、Pb2+、As3+、As5+、Hg2+对Sb的干扰可以有效地消除;样品Sb含量在0.92～2.52 mg/kg之间波动,平均值为1.76 mg/kg,与四川省土壤Sb背景浓度(≈1.70 mg/kg,1991)相比相差不大。水平方向上,各形态Sb的浓度因所处稻田条件的不同而分布各异,大体呈以下规律:残渣态﹥有机/硫化物结合态﹥铁/锰氧化物结合态﹥碳酸盐结合态﹥可交换态,易被植物吸收利用的可交换态占的比率最小;垂直方向上,各形态随着土壤深度的增加,呈递减趋势。     

氢化物发生-双通道原子荧光光谱法同时测定茶叶和木耳中硒及汞量

经洗净烘干并磨碎的试样在硝酸中浸泡过夜后在硝酸-高氯酸中消解,蒸发至冒白烟并继续蒸至近干,加入一定量的盐酸微沸1～2min,使硒(Ⅵ)还原为硒(Ⅳ),溶液用盐酸(5+95)定容至50mL。此溶液由载流盐酸(5+95)溶液送入氢化物发生器,与还原剂10g.L-1 KBH4溶液混合并反应生成硒的氢化物,样品中汞则生成原子态汞蒸气。两者由载气引入原子化器,在选定的仪器工作条件下,测定硒及汞的荧光强度。在实际样品中,硒、汞共存的浓度比未超过10,在同时测定中两者之间互不干扰。按所提出的条件测定,硒、汞的质量浓度在1.0～5.0μg.L-1范围内与相应的荧光强度值之间呈线性关系,方法的检出限(3s/k)依次为0.077,0.009 8μg.L-1。对仪器测定精密度做了试验,测得其相对标准偏差(n=7)依次为1.98%,1.31%。