负载Fe3（CO）12催化剂的制备及合成氨的催化活性

以Ｆｅ_３（ＣＯ）_（１２）为母体，以活性氧化铝或活性炭为载体制备了负载型氨合成催化剂．在固定床管式流动反应系统中测定了催化活性，并与以Ｒｕ_３（ＣＯ）_（１２）和ＲｕＣｌ_３·ｘＨ_２Ｏ为母体的负载催化剂以及低温高活性氨合成工业催化剂的活性进行了对比。结果表明：以活性炭为载体的Ｆｅ_３（ＣＯ）_（１２）催化剂在１５ＭＰａ、４００℃以上表现出很高活性，且每克纯活性组分的催化活性在某些温度下比当前活性较高的工业熔铁催化剂的活性要高得多，但低温常压下几乎无活性。负载钉催化剂在低温常压下即显活性，且以ＲｕＣｌ_３·ｘＨ_２Ｏ为母体，比以Ｒｕ_３（ＣＯ）_（１２）为母体的负载钌催化剂活性高。     

Highly luminescence manganese doped carbon dots

Heteroatom doped carbon dots(CDs) with distinct merits are of great attractions in various fields such as solar cells, catalysis, trace element detection and photothermal therapy. In this work, we successfully synthesized blue-fluorescence and photostability manganese-doped carbon dots(Mn-CDs) with a quantum yield up to 7.5%, which was prepared by a facile one-step hydrothermal method with sodium citrate and manganese chloride. The Mn-CDs is the high mono-dispersity, uniform spherical nanoparticles. The Mn element plays a critical role in achieving a high quantum yield in synthesis of carbon dots, which was confirmed by the structure analysis using XPS and FTIR. Spectroscopic investigations proved that the decent PLQY and luminescence properties of Mn-CDs are due to the heteroatom doped, oxidized carbon-based surface passivation. In addition, the Mn-CDs are demonstrated as promising fluorescent sensors for iron ions with a linear range of 0–500 mmol/L and a detection limit of2.1 nmol/L(turn-off), indicating their great potential as a fluorescent probe for chemical sensing.     

不同结晶速率的PET薄膜在拉伸过程中的结晶与取向

用多种方法对两个结晶速率不同的PET样品在拉伸过程中的结晶和取向进行了研究。结果表明在同样的拉伸条件下,结晶速率较快的样品的结晶度和取向程度均比另一样品要高得多,这种结构变化上的差别说明把拉伸行为的差别归因于结晶速率的不同是合理的。     

阴离子在构筑吡啶酰胺－铜(II)配位超分子体系中的作用

Three complexes Cu（ppca）2（H2O）2（NO3）2 （1）, Cu2（μ-OH）2（ppca）2（H2O）4）·（ClO4）2 （2） and Cu2（μ-CH3COO）4（ppca）2（3） have been synthesized by the reaction of copper（Ⅱ） salts with N-phenyl-4-pyridinecarboxamide （ppca） and characterized. For anions, in complex 1, NO3^- coordinated with copper（Ⅱ）, in complex 2 perchlorate anion did not take part in coordination, the copper（Ⅱ） cations were connected by μ-OH to form a dinuclear unit, and complex 3 had a dimeric copper（Ⅱ） carboxylate paddle-wheel core. Noncovalent interactions linked these complexes to form supramolecular networks. Different coordinating modes of anions controlled modes of intennolecular interactions, which resulted in different final structures.     

INDO STUDIES ON THE ELECTRONIC STRUCTURE OF[Ln(CCl_3COO)_3·phen·C_2H_5OH]_2(Ln=Pr,Sm)

The electronic structure and chemical bonding of the title comp-lexes have been studied by an unrestricted INDO program made applicable forthe lanthanoid compounds.The results indicated:(1)In coordinated bonds O-Lnand N-Ln,5d orbitals of Ln have large contribution in all valence orbitalsof Ln and 4f orbitals have very small contribution.(2)The covalent chara-cter and ionic character are almost equal in the chemical bond which iscomparatively weak between phen,C_2H_5OH and Ln are mainly ionic with somecovalent character.     

Control of polymer topology by chain-walking catalysts

Chain-walking catalysts are demonstrated to control the branching topology of polyethylene by tuning the competition between monomer insertion and chain isomerization (walking). The topology of the polyethylene was controlled from linear with moderate branching to hyperbranched to dendritic. Although overall branching number and distribution of short chain branching are relatively constant, the topology of the polyethylene changes from linear polyethylene with moderate branches at high ethylene pressures to a dendritic polyethylene at low pressures. This provides a straightforward one-pot process for making polymers with a full range of tunable topologies.     

单级高压微流量电渗泵的研究

设计了一种高压微流量电渗泵。泵体主要由高压电源、电渗柱、毛细通道、导电空心电极以及气泡去除器、压力传感器等构成。单级电渗泵可以给出0～20MPa范围的输出压力和nL～μL级输出流量。输出压强和输出流量取决于电压、填充柱阻力和流体性质。     

Effect of heating and stretching membrane on ionic conductivity of sulfonated poly(phenylene oxide)

With chlorosulfonic acid as sulfonating agent, sulfonated poly(phenylene oxide) (SPPO) was prepared by homogeneous method and SPPO membranes were cast from its solutions in dimethylacetamide. The obtained membrane of SPPO was heat-treated and stretched with different forces by thermal mechanical analyzer under its glass transition temperature. In addition, the effects of stretching and heating on ion conductivity of SPPO were investigated by using Solatron phase analyzer. It was shown that the mechanical stretching of SPPO has great effect on electric properties of SPPO under proper heating treatment, and the highest conductivities achieved were increased about 10 times that of the original membranes and reached 0.0983 S cm⁻¹. The X-ray diffraction indicated that the molecular chains of SPPO were arranged more regularly under constraint during the heat treatment, and the scanning electron microscopy demonstrated that the morphologies of the film surfaces possessed more co-continuous regions and the hydrophilic ionic sulfonic acid groups orientated at stretching direction and connected more regularly, which facilitated the exchange and transfer of hydrated proton among these hydrophilic sulfonic acid groups.     

Structure determination of germacrane-type sesquiterpene alcohols from an endophyte Streptomyces griseus subsp

Three germacrane-type sesquiterpene alcohols were isolated from an endophyte of mangrove plant Kandelia candel. Their structures were characterized as 1(10)E,5E-germacradiene-11-ol (1), 1(10)E,5E-germacradiene-3,11-diol (2), 1(10)E,5E-germacradiene-2,11-diol (3) based on the extensive NMR studies. Among them, 2 and 3 are identified as new compounds.     

Studies on Volumetric Properties of Concentrated Aqueous Solutions of the Ionic Liquid BMIBF4

In order to test the mole-fraction composition-based models as applied to aqueous solutions of an ionic liquid, the densities of aqueous 1-methyl-3-butylimidazolium tetrafluoroborate (BMIBF₄) were measured using a Westphal balance in the concentration range of about 0.2 to 0.85 mole fraction at temperatures from 283.2 to 323.2 K. Values of the apparent molar volumes of concentrated aqueous BMIBF₄ solutions were calculated from these densities and were represented with the Pitzer–Simomson and the Pitzer–Simomson–Clegg equations. The values of Pitzer–Simomson parameters and Pitzer–Simomson–Clegg parameters were obtained by fitting to experimental data with small standard deviations.