超临界流体技术在催化反应和金属有机反应中的应用

本文详细地介绍了超临界流体技术在催化反应和金属有机反应中近10年来国内外发展的最新成果及动向,表明将超临界流体技术应用于催化反应中,将提高催化剂活性,选择性及寿命,并可提高反应速率,改变反应历程,特别是在开展控制化学及环境友好的绿化学反应方面的研究具有很大的潜在优势。     

1-环丙基-6-氟-7-取代喹诺酮抗HIV活性的定量构效关系

用量子化学AM1法对一系列1-环丙基-6-氟-7-取代-1,4-二氢-4-氧-喹啉-3-羧酸的定量构效关系进行了研究,结果表明该类化合物在对HIV的抑制过程中是一很好的电子给予体,给电子的部位主要是7-位哌嗪基末端氮原子,并进一步提出从抗C^+和G^-菌活性差的喹诺酮中有望筛选出好的抗HIV化合物。     

钡原子6p3/2ns自电离里德伯态的研究

用激光多步激发技术研究了处于６ｐ１／２电离限以下的６ｐ３／２ｎｓ自电离态的光谱。并利用最 Ｒ矩阵的计算结果,结合多通道量子亏损理论进行了理论分析,理论结果与实验光谱相符合。     

LC/MS/MS determination and pharmacokinetic study of iridoid glycosides monotropein and deacetylasperulosidic acid isomers in rat plasma after oral administration of Morinda officinalis extract

Morinda officinalis is a famous traditional Chinese medicine containing iridoid glycoside compounds, such as monotropein and deacetylasperulosidic acid. The aim of the study was to develop a novel and sensitive liquid chromatography–tandem mass spectrometry (LC/MS/MS) method for the simultaneous determination of the two isomeric iridoid glycosides and then evaluate their pharmacokinetic properties in rats. Selected‐reaction monitoring mode was employed for quantification of two analytes in rat plasma. The calibration curves were linear over their respective concentration range with correlation coefficient >0.995 for both analytes. Precision for monotropein and deacetylasperulosidic acid ranged from 2.5 to 11.9% relative standard deviation, and the accuracy of two analytes was ?2.0–3.7 and ?6.4–10.7% relative error, respectively. This method was successfully applied in pharmacokinetic study after oral administration of M. officinalis extract in rats. The results provided a basis for further research on the bioactivity of M. officinalis. Copyright © 2015 John Wiley & Sons, Ltd.     

氯化钙在10X分子筛上的微波强化分散及其氨吸附的研究

利用干混法将氯化钙担载于10X分子筛上,通过微波法强化分散,研究了不同条件下样品的XRD图和氨吸附量,并与同样氯化钙担载量的焙烧法样品进行了比较.结果表明,微波法能显著提高CaCl2的分散度,且对应样品的氨吸附量显著提高.CaCl2在10X分子筛上的单层分散阈值在0.4 g/g～0.5 g/g之间,担载量为0.5 g/g的样品的氨吸附量最大,在35℃时达到0.575 g/g.在85 ℃时样品的吸附量都很小,这对利用低温余热脱附很有利.样品的适宜微波处理时间在10 min～20 min之间.同时,利用比表面分析和红外光谱分析证明微波法可以强化分散且不改变分子筛结构.     

(4-溴甲基双环[4.4.1]-1,3,5,7,9-十一碳五烯基-3-)甲醇环氧化反应机理的理论研究

采用量子化学的密度泛函理论(DFT),在B3LYP/6 31G*水平上研究了(4 溴甲基双环[4. 4. 1] 1, 3, 5,7, 9 十一碳五烯基3 )甲醇环氧化反应机理,在对反应物和产物几何结构优化的基础上,搜索优化了反应的过渡态结构,通过振动分析和内禀反应坐标(IRC)跟踪方法对过渡态及其所处的反应路径进行了确认,并用电荷密度拓扑分析方法考察了反应过程中旧键断裂和新键形成的细节.计算结果表明,该反应中的消除反应和成环反应是协同进行的,溴化氢消除反应中的氢来自与O( 22 )相连的羟基氢,反应的活化势垒为139. 2kJ/mol,反应放热25. 1kJ/mol.     

Technology of preparing anode films and the effect of co-sensitization in dye-sensitized solar cells

Nanocrystalline N–Zn/TiO₂ anode films were prepared by doping element N and Zn. These element-doped films have a better performance in dye-sensitized solar cell than the non-doped film. The test shows that the best thickness of N–Zn/TiO₂ anode film is 13.5 μm. UV–Visible measurements show that there is a complementarity in ultraviolet–visible absorbance range between P3OT and N719, both are used as dyes in this study, the former is prepared and the latter is commercially available. SEM shows a significant mass increase of anode film after treated with TiCl₄. Solar cells based on N–Zn/TiO₂ anode film with TiCl₄ treatment was firstly co-sensitized by N719/P3OT. A solar-to-electric energy conversion efficiency of 3.54 % was obtained. Compared with the traditional dye-sensitized solar cell, the photoelectric conversion efficiency, V _oc and J _sc have been increased.     

Synthesis and application in solar cell of poly(3-dodecylthiophene)/titanium dioxide nanocomposite

A conducting polymer composite poly(3-dodecylthiophene)/titanium dioxide (P3DDT/TiO₂) nanocomposite was first synthesized through the ultrasonic method. The results from X-ray diffraction (XRD) and infrared spectroscopy (IR) show that there is chemical interaction in the composite. Transmission electron microscope (TEM) and scanning electron microscope (SEM) depict the morphology of the samples, defining that TiO₂ was successfully coated by poly(3-dodecylthiophene) molecules. The energy gap of the poly(3-dodecylthiophene)/titanium dioxide composite is lower to 0.76 eV compare with poly(3-dodecylthiophene) and titanium dioxide separately, and it also shows that the optical performance of the new material is far superior than P3DDT or TiO₂ separately by ultraviolet-visible spectra (UV) and fluorescence spectroscopy (PL). Solar cell was sensitized by P3DDT/TiO₂. A solar-to-electric energy conversion efficiency of 0.188% was attained with the system.     

Effects of annealing ambience on ZnO:N films grown by MOCVD and the p-type doping mechanism of ZnO:N films investigated by XANES

ZnO:N thin films were deposited on sapphire substrate by metal organic chemical vapor deposition with NH₃ as N-doping sources. The reproducible p-type ZnO:N film with hole concentration of ∼10¹⁷ cm⁻³ was successfully achieved by subsequent in situ thermal annealing in N₂O plasma protective ambient, while only weak p-type ZnO:N film with remarkably lower hole concentration of ∼10¹⁵ cm⁻³ was obtained by annealing in O₂ ambient. To understand the mechanism of the p-type doping behavior of ZnO:N film, X-ray photoelectron spectroscopy (XPS) and soft X-ray absorption near-edge spectroscopy (XANES) measurements have been applied to investigate the local electronic structure and chemical states of nitrogen atoms in ZnO:N films.     

迎风型TVD格式在高速进气道粘性流动模拟中的应用

迎风型ＴＶＤ格式在高速进气道粘性流动模拟中的应用刘晶昌，徐建中（中国科学院工程热物理研究所北京１０００８０）邢君波（航天部３１所北京１０００８０）关键词超音速进气道，数值模拟，Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程１前言高速进气道流动做为一种非常复杂的流动，...