2-[2-(7H-二苯并[a,g]咔唑)-乙氧基]-乙基氯甲酸酯对脂肪胺类化合物的荧光标记及质谱鉴定

利用新型荧光标记试剂2-[2-(7H-二苯并[a,g]咔唑-乙氧基)-乙基氯甲酸酯作为柱前衍生化试剂, 在Eclipse XDB-C8反相色谱柱上,采用梯度洗脱,实现了12种脂肪胺类化合物完全基线分离.检测最佳激发和发射波长分别为300和400 nm.通过荧光检测及离子阱大气压化学电离源(APCI Source)正离子模式实现了在线的柱后质谱鉴定.对土壤中脂肪胺类化合物的测定快速、准确,具有良好的重现性.荧光定量检测的回归系数大于0.9991; 检出限为10.1～0.3 fmol.     

β-二酮、邻菲罗啉分别与铕和铽三元配合物的合成及发光性能研究

为了寻找新的发光材料并研究β-二酮对稀土配合物发光性能的影响, 我们合成了一个新的β-二酮配体: 1-苯 基-3-(对苯乙炔苯基)-1,3-丙二酮(HPPP), 并用HPPP、邻菲罗啉(phen)分别与Eu(III)和Tb(III)反应, 合成了两个新的三元稀土配合物: Eu(PPP)3phen和Tb(PPP)3phen, 通过红外光谱、化学分析、元素分析对三元稀土配合物的组成和结构进行了表征. 研究了配合物的荧光性质, 发现β-二酮配体对配合物的发光有较大影响, 通过量子化学计算对实验结果进行了解释.     

New implementations of MRCI in semiempirical frameworks

Multireference configuration interaction with single and double excitations (MRCISD) as well as its analytic CI gradients has been implemented in the semiempirical framework. The hole‐particle symmetry and a mixed driven model for computing coupling coefficients have been used in the new code that allows us to perform MRCI and gradient calculations with higher efficiency and less storage requirements. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010     

ZrO_2、TiO_2担载氧化铁催化剂上二氧化碳加氢制低碳烃(英文)

采用创新方法制备的ZrO2、TiO2担载氧化铁催化剂在二氧化碳加氢制低碳烃反应中显示出良好的催化活性和产物选择性,由15wt?/ZrO2给出的最佳结果为：CO2转化率为20%,除甲烷以外的低碳烃的选择性接近70%。还考察了金属Fe担载量及催化剂的预还原温度对催化活性的影响,发现催化活性随金属Fe担载量的增加而呈现“双峰”现象,这种现象可能与活性物种(零价铁及配位不饱和的三价或二价铁)在催化剂表面的几何排布有关,而两种催化剂的最佳还原温度分别为723 K(5wt?/ZrO2)和773 K(5wt?/TiO2)。     

(μ3-S)FeCo2(CO)7(dppfe)的合成和晶体结构

通过简单取代反应,合成了一个新的混金属簇合物(μ3-S)FeCo2(CO)7(dppfe) (2) (dppfe=Ph2PC5H4FeC5H4PPh2).利用IR,1H NMR,MS 和 X-ray单晶衍射的方法对簇合物2进行了结构表征.簇合物2的晶体属于三斜晶系,空间群为Pī.晶胞参数: a=1.132 4(15) nm, b=1.3670(17) nm, c=1.5769(2) nm,α=114.646(2)°,β=100.340(2)°,γ=100.113(3)°, V=2.0953(5) nm3.     

Catalytic Combustion of Methane over Ti-Pillared Clay Supported Copper Catalysts

A natural montmorillonite, produced from Laiyang of Shandong Province, was pillared by Tipolycations to form Ti-pillared clay (Ti-PILC), and characterized by BET surface area, infrared spectra and thermal analysis. The characterization results show that Ti-PILC has a larger surface area and more hydroxyl groups than that of the natural clay, thus was used as the catalytic carriers to prepare supported Cu catalysts (Cu/TiopILC). The 20%Cu/Ti-PILC with 10mmol/g of Ti/clay shows a high catalytic performance of methane combustion in the temperature range of 400-500℃.     

Effects of carbon sources and carbon contents on the electrochemical properties of LiFePO4/C cathode material

LiFePO₄/C composites are prepared by using two types of carbon source: one using polymer (PAALi) and the other using sucrose. The physical characteristics of LiFePO₄/C composites are investigated by X-ray diffraction), scanning electron microscopy, BET, laser particle analyzer, and Raman spectroscopy. Their electrochemical properties are characterized by cyclic voltammograms, constant current charge–discharge, and electrochemical impedance spectra. These analyses indicate that the carbon source and carbon content have a great effect on the physical and electrochemical performances of LiFePO₄/C composites. An ideal carbon source and appropriate carbon content can effectively increase the lithium-ion diffusion coefficient and exchange current density, decrease the charge transfer resistance (R _ct), and enhance the electrochemical performances of LiFePO₄/C composite. The results show that PAALi is a better carbon source for the synthesis of LiFePO₄/C composites. When the carbon content is 4.11 wt.% (the molar ratio of PAALi/Li₂C₂O₄ was 2:1), as-prepared LiFePO₄/C composite shows the best combination between electrochemical performances and tap density.     

Calorimetric Studies on Enthalpy Relaxation in Maltitol Glass Transition Based on Phenomenological Models

To investigate the enthalpy relaxation behavior of maltitol glass system, differential scanning calorimetry (DSC) was used to obtain the specific heat capacity[C_p(T)] near the glass transition temperature(T_g) at different coo- ling rates ranged between 1 and 20 K/min. Three phenomenological models of enthalpy relaxation, Tool-Narayanaswamy-Moynihan(TNM) model, Adam-Gibbs-Vogel(AGV) model and Gómez Ribelles(GR) model, were used to simulate the experimental data. The models’ parameters were obtained via a curve-fitting method. The results indicate that TNM and AGV models gave the almost identical prediction powers and can reproduce the curves of experimental C_p(T) very well. However, the prediction power of GR model evolved from configurational entropyapproach is not so good as those of TNM and AGV models. In particular, the metastable limit state parameter(δ) introduced by Gómez Ribelles has insignificant effect on the enthalpy relaxation of the small molecular hydrogen-bonding glass system.     

藏药香芸火绒草Leontopodium Haplophylloides化学成分的研究

从藏药香芸火绒草Leontopodium Haplophylloides Hand Mazz的甲醇提取物中分得四个B环未取代的黄酮, 分别为乔松素(1), 高良姜素(2), 3, 7-二羟基-5-甲氧基黄(3), 3, 5-二羟基-7-甲氧基黄酮(4), 化合物(2)对人皮肤痤疮菌具有一定的疗效。     

Ionic liquid-regulated sulfamic acid: chemoselective catalyst for the transesterification of β-ketoesters

1-Propyl-3-methylimidazolium chloride ([C₃MIm]Cl) ionic liquid and sulfamic acid (NH₂SO₃H), as a synergetic catalytic medium, were used for the transesterification of acetoacetate with alcohols of different structures. It shows the good ability for the chemoselective transesterificatin of β-ketoesters and maintains its catalytic activity in the reuse.