Fe/Zn双金属氰化物催化剂催化环氧丙烷聚合的活性结构研究

以氯化锌、铁氰化钾（含有整合剂）的水溶液为原料，合成了铁锌双金属氰化物（DMC）催化剂。为获得高活性的DMC催化剂，需将叔丁醇 、多元醇螯合剂螯合至其结构中，用XRD、XPS等分析手段，对铁锌DMC催化剂的结构与活性进行分析表征。实验发现，DMC催化剂的晶体结构与螯合剂密切相关，螯合剂能显著降低DMC催化剂的结晶程度，从而提高DMC催化剂的活性。同时，氯化锌过量也有利于DMC催化剂活性的提高。并表征了相关DMC催化剂的活性中心。     

多色蓝在核酸分子上的Langmuir聚集吸附

用微相吸附-光谱修正（MPASC）新技术研究核酸与多色蓝(PCB)探针分子间的相互作用，分析核酸分子内双静电膜的形成与Langmuir吸附的关联性.通过pH 7.24的介质核酸-PCB反应的光谱研究，测定了结合产物的物理化学参数：结合比1PCB:2DNA-PCB、1PCB:3RNA-PCB, 平衡常数KDNA-PCB=5.42×104， KRNA-PCB=2.82×104,摩尔吸收系数ε(DNA-PCB, 625 nm)=5.65×103（mo1－1•L ）•cm－1， ε(RNA-PCB, 625 nm)=3.85×103 （mol－1•L）•cm－1.结果表明， RNA分子仅形成约60％双螺旋结构链，核酸双螺旋每一周期的负静电沟最大聚集10个PCB分子.该吸附反应用于核酸样品测定，结果良好.     

Non‐Planar Lithium‐Phthalocyanine in the Double Salt (nBu4N)2[Lipc]PF6

We report the synthesis of the diamagnetic double salt bis(tetra(n‐butyl)ammonium) phthalocyanato(2‐)lithate hexafluorophosphate (nBu₄N)₂[Lipc]PF₆ [pc = phthalocyanine, nBu₄N⁺ = tetra(n‐butyl)ammonium] in dme (dme = dimethoxyethane). According to single‐crystal X‐ray diffraction structure analysis [P$\bar{1}$ , a = 8.642(2) Å, b = 12.820(3) Å, c = 15.019(3) Å, α = 83.01(3)°, β = 87.87(3)°, γ = 74.45(3)°, Z = 1, R₁ = 6.4 %], the phthalocyanine building bloc shows a substantial distortion of the macrocyclic ring from planarity. The deviation from D_4h symmetry originates from packing effects induced by the two tetra(n‐butyl)ammonium cations located above and below the macrocycle. DFT structure optimization starting from the experimental non‐planar configuration produces a fully planar complex anion [Lipc]^–.     

The non-integer cyclovoltammetric electron-exchange numbers of reversible redox reactions of adsorbates

Allowing for the interfacial potential distribution it can be shown that the apparent faradaic electron number, n_app, of ad-layers of chemically modified electrodes and the surface redox valency, n, relating to the slope of the peak potential/pH response [Huck (2002) J Solid State Electrochem 6:534] are at least identical, having the same thermodynamic origin. n_app is calculated from the cyclovoltammetric (CV) peak areas above the interpolated base line. At for proton-coupled surface redox reactions, the influence of the potential drop of the diffuse double layer disappears because the capacitor of the corresponding equivalent circuit becomes shortened by proton transfer, whereby the otherwise non-integer n_app or n values now approach the integer electron numbers, n, of the Nernst equation.

液态低沸点气体的表面张力

利用双毛细管法测定了液氮沸点温度下液氮的表面张力。用非线性方程γ=γ0(1-T/TC)n描述了液态N2、O2、Ar、Xe、H2、Ne、He、F2和Kr的表面张力与温度的关系,并采用一元线性回归的方法拟合了上述各流体的参数γ0和n,准确度高于文献值,说明方程能正确表达表面张力与温度的关系。这些数据有利于对上述低沸点气体进行准确的热力学计算。     

An expedient synthesis of ellipticine via Suzuki-Miyaura coupling

A simple and efficient total synthesis of ellipticine was developed via the Suzuki-Miyaura coupling of sterically sensitive 2-hydroxybenzeneboronic acid with a multifunctional aryl halide using Pd(OAc)₂ as a catalyst and Cu(OAc)₂·H₂O as an additive in DMSO/H₂O as a key step followed by double N-arylation and cyclization.     

Degree of order and redox balance in B-site ordered double-perovskite oxides, Sr2MMoO6−δ (M=Mg, Mn, Fe, Co, Ni, Zn)

We have investigated a series of double-perovskite oxides Sr₂MMoO_6−δ (M=Mg, Mn, Fe, Co, Ni, Zn) for redox stability, oxygen content and crystal structure. Phases with M=Co, Ni and Zn were found to be oxygen-stoichiometric and stable under oxidizing conditions, whereas those with M=Mn and Fe were oxygen-deficient and stable under reducing conditions. The M=Mg phase is stable both under reducing and oxidizing conditions, showing variable oxygen contents within 0.00≤δ≤0.04 depending on the annealing conditions. Structural data indicate somewhat depressed values for the degree of M/Mo cation order and also evidence of electron transfer from M^II to Mo^VI for M=Mn, Fe and Co.     

Theoretical analysis of the performance of a model supercapacitor consisting of metal oxide nano-particles

The factors influencing the electrochemical behaviour of a supercapacitor have been partly examined in this work. The effects of so-called intrinsic parameters, i.e. exchange current density, unit cell length and double layer (DL) capacitance; as well as the so-called application parameters, i.e. cell current, on the cell potential discharge time have been considered. The contributions of each type of capacitors, DL capacitor and faradaic supercapacitor under various states of operation and material have been analyzed, and the competing (compensating) effects of the two types of capacitors as regards to the discharge and power characteristics manifested by current–potential and energy–power (Ragone plots) are elucidated.     

Diffusion Coefficients of Tris(<Emphasis Type="Italic">β</Emphasis>-diketonato)ruthenium Complexes of Different Charge Numbers in Acetonitrile Solutions,Measured by Chronoamperometry

The diffusion coefficients of several tris(β-diketonato) ruthenium complexes in acetonitrile solutions containing a supporting electrolyte were determined by chronoamperometry. The diffusion coefficients of the charged complexes, which were produced by electrochemical oxidation or reduction, were also determined by double potential step chronoamperometry. Two kinds of radii of the complexes were evaluated. One was the Van der Waals radius and the other was the geometric distance from the center of the complex to the outer surface of the farthest atom. The latter quantity was determined from X-ray diffractometric data. The diffusion coefficients of the neutral complexes were discussed on the basis of the Stokes-Einstein equation. Those of charged complexes could not be explained by the theoretical equation presented by Hubbard and Onsager.