Structural,Electronic and Optical Properties of the Monoclinic α-CoV_2O_6

First-principles calculations based on density functional theory are performed to investigate the structural,electronic and optical properties of monoclinic α-Co V2O6.Firstly,the geometry structures obtained by geometry optimization are consistent with the experimental values.Then,the energy band structure is studied using both GGA and GGA+U methods.It is found that the on-site Coulomb repulsion of the Co 3d orbital plays a key role in describing the electronic properties of α-Co V2O6,and is necessary to open the energy band gap.According to the partial density of states(PDOS),significant Co–O and V–O hybridizations are observed in the valence and conduction bands,respectively.Furthermore,the Co–O and V–O bonds are found to have significant covalent characters.Below the absorption threshold ~1.9 e V,no absorption can be detected.However,there exists a strong and wide absorption band in the energy range from 1.9 to 11 e V.Such novel optical properties imply that the α-Co V2O6 may have some potential optical applications.     

Synthesis and Crystal Structure of Sm Cu7.73In3.27: a New 3D Framework Based on [Cu5In4M4]（M=Cu/In） Cluster

A new intermetallic compound, SmC u7.73In3.27, has been synthesized by solid-state reaction of the corresponding pure elements at high temperature, and structurally characterized by single-crystal X-ray diffraction study. SmC u7.73In3.27 crystallizes in tetragonal space group P4/mbm with a = 8.6213(4), c = 10.2538(9), V = 762.13(8) A3, Z = 4, Mr = 1018.90, Dc = 8.880 g/cm3, μ =38.244 mm-1, F(000) = 1789, and the final R = 0.0374 and w R = 0.0836 for 514 observed reflections with I 2σ(I). The structure of SmC u7.69In3.31 belongs to a new structure type and features a three-dimensional(3D) [Cu5In2M4](M = Cu/In) framework composed of [Cu5In4M4] clusters interconnected via sharing In atoms as well as Cu–In and In–In bonds. The Sm atoms are located in the one-dimensional(1D) tunnels along the c-axis. The structural relationship of the title compound with other similar Sm-Cu-In phases was also studied. Band structure calculations based on Density Functional Theory(DFT) method indicate that SmC u7.69In3.31 is metallic.     

Highly Segregated Lamello‐Columnar Mesophase Organizations and Fast Charge Carrier Mobility in New Discotic Donor–Acceptor Triads

Four new donor–acceptor triads (D–A–D) based on discotic and arylene mesogens have been synthesized by using Sonogashira coupling and cyclization reactions. This family of triads consists of two side‐on pending triphenylene mesogens, acting as the electron‐donating groups (D), laterally connected through short lipophilic spacers to a central perylenediimide (PI), benzo[ghi]perylenediimide (BI), or coronenediimide (CI) molecular unit, respectively, playing the role of the electron acceptor (A). All D–A–D triads self‐organize to form a lamello‐columnar oblique mesophase, with a highly segregated donor–acceptor (D–A) heterojunction organization, consequent to efficient molecular self‐sorting. The structure consists in the regular alternation of two disrupted rows of triphenylene columns and a continuous row of diimine species. High‐resolution STM images demonstrate that PI‐TP2 forms stable 2D self‐assembly nanostructures with some various degrees of regularity, whereas the other triads do not self‐organize into ordered architectures. The electron‐transport mobility of CI‐TP2, measured by time‐of‐flight at 200 °C in the mesophase, is one order of magnitude higher than the hole mobility. By means of this specific molecular designing idea, we realized and demonstrated for the first time the so‐called p–n heterojunction at the molecular level in which the electron‐rich triphenylene columns act as the hole transient pathways, and the coronenediimide stacks form the electron‐transport channels.     

Total Syntheses of (−)‐Isoschizogamine and (−)‐2‐Hydroxyisoschizogamine

Total syntheses of (?)‐isoschizogamine and (?)‐2‐hydroxyisoschizogamine are described. The synthesis employs two asymmetric Michael additions to establish chiral centers at C7 and the quaternary carbon C20. Regioselective reduction of the methylthioiminium cation rather than the enamine generates an isoschizogamine‐type pentacyclic skeleton. Acidic hydrolysis of the isoschizogamine‐type intermediate in the absence of oxygen provides natural (?)‐isoschizogamine. Conducting the reaction in the presence of oxygen leads to a multistep oxidative hydrolysis cascade that affords unnatural (?)‐2‐hydroxyisoschizogamine.     

钴( Ⅱ)与1,3-间苯咪唑及间苯二甲酸根构筑的两个配位聚合物的合成、晶体结构及性质

以间苯咪唑(1,3-bib)和间苯二甲酸(H2MPA)为配体,在温和的水热条件下,合成了Co( Ⅱ)的2个配位聚合物{[Co(1,3-bib)(MPA)(H2O)2]·H2O}n(1)和{[Co2(1,3-bib)2(MPA)2]·5H2O}n(2),分别用X-射线单晶衍射、元素分析、IR和热重等手段对它们进行了表征,结果表明,配位聚合物1为1D层状结构,属于正交晶系,Pnma空间群;配位聚合物2为双核2D结构,属于三斜晶系,P1空间群。在室温下研究了它们的光学性质。     

Preparation,characterization and hydrodesulfurization performances of Co-Ni2P/SBA-15 catalysts

A series of Co-Ni2P/SBA-15 catalysts with various Co contents, Ni2P contents and P/Ni molar ratios were prepared by impregnating nickel nitrate, diammonium hydrogen phosphate, and then cobalt nitrate into SBA-15 support followed by temperature-programmed reduction in a H2 flow. The catalyst structure was characterized by X-ray diffraction(XRD), high resolution-transmission electron microscopy(HR-TEM)and N2adsorption-desorption techniques and their catalytic performance of the hydrodesulfurization(HDS) of dibenzothiophene(DBT) was evaluated. The effects of Co contents, Ni2 P contents and P/Ni molar ratios on the catalyst structure and HDS of DBT over the Co-Ni2P/SBA-15 catalyst were investigated. The results indicated that the mesoporous structure was mainly maintained and the nickel phosphides were well dispersed in all of the characterized catalysts. The 4Co-25Ni2P/SBA-15(P/Ni = 0.8) catalyst with the Co and Ni2 P contents of 4 wt% and25 wt%, respectively, and the P/Ni molar ratio of 0.8 showed the highest catalytic performance for HDS of DBT. Under the reaction conditions of 380?C and 3.0 MPa, the DBT conversion can reach 99.62%. The HDS of DBT proceeded mainly via the direct desulfurization(DDS)pathway with biphenyl(BP) as the dominant product on all of the catalysts and the BP selectivity was slightly enhanced after the introduction of Co promoters.     

地质环境样品中挥发酚分析现状与进展

挥发酚被列为环境优先控制的有机污染物,已成为评价环境污染的重要指标之一。该文简述了挥发酚的化学性质及地质环境来源,概括了国内外挥发酚测定的相关标准方法,从样品预处理技术和检测技术两方面综述了近年来地质环境样品中挥发酚分析的研究现状。重点对溶剂萃取、蒸馏、固相萃取、固相微萃取和吹扫捕集等样品预处理技术,以及4-氨基安替比林分光光度法、紫外和荧光分光光度法、溴化容量法、气相色谱法、液相色谱法和酚生物传感器法等技术在地质环境样品中挥发酚分析上的应用进行了较为全面的总结,并对其未来的发展趋势进行了展望,为进一步研究挥发酚的分析技术及其环境应用提供参考。     

重组人胰岛素注射液中B3和B3iso脱氨人胰岛素的分析与鉴定

建立了有效分离重组人胰岛素注射液中B3和B3iso脱氨人胰岛素的反相高效液相色谱(RP-HPLC)法,并采用高效液相色谱-四极杆-飞行时间质谱联用技术(HPLC-MS/MS)对其进行氨基酸序列的鉴定。在《中国药典》2010版重组人胰岛素注射液有关物质检查分析方法的基础上,优化流动相p H值,以0.2mol/L硫酸盐缓冲液(p H 3.6)-乙腈(90∶10)作为A相,乙腈-水(50∶50)为B相,梯度洗脱,分别收集杂质峰1和杂质峰2,脱盐浓缩后,用丝氨酸蛋白酶(V8酶)酶切,取部分酶切溶液经三(2-羧乙基)膦盐酸盐(TCEP)还原,分别得到还原和非还原肽段溶液,利用LC-MS/MS鉴定氨基酸序列,未知杂质分别为重组人胰岛素B3位发生脱氨和异构化的产物,即B3和B3iso脱氨人胰岛素。将优化后的方法与《中国药典》方法对市售重组人胰岛素注射液进行有关物质的对比分析,已上市厂家的重组人胰岛素注射液均有不同程度的B3和B3iso脱氨人胰岛素存在。该方法不影响重组人胰岛素其它有关物质的检测,可用于监控人胰岛素注射液产品储存过程中脱氨类杂质的增长趋势。