A Novel Pharmacophore Model Derived from a Class of Capsid Protein Enterovirus 71 Inhibitors

Capsid protein enterovirus 71 (EV71) is one of the major viruses that cause the severe encephalitis and thus result in a high mortality in children less than 5 years of age.In an effort to discover new potent inhibitors against EV71,a novel three-dimensional pharmacophore model was developed on 24 inhibitors with different molecular structures and bioactivities.The best hypothesis (Hypo1) has a high predictive power and consists of four features,namely,one hydrophobic point (HY) and three hydrogen-bond acceptors (HA).Two key features of the best Hypo1,HY1 and HA3 match well with an important narrow hydrophobic canyon and with the surface of LYS274 in the target EV71 active site,respectively.The more versatile feature,HA1,is firstly found to be very influential on these compounds' bioactivities,which may interact with the other side of the active site in the EV71 receptor.The application of the model is successful in predicting the activities of 30 known EV71 inhibitors with a correlation coefficient of 0.831.Furthermore,Hypo1 demonstrates a superior screening capability for retrieving inhibitors from the database with a high enrichment factor of 70.This study provides some important clues in search for more potent inhibitors against EV71 infection.     

高校建筑设计方案节能性模糊综合评价

针对高校新建建筑设计方案的节能性,从方案设计、节能材料及措施、节能器具和新能源4个方面建立评价指标体系,运用模糊数学和层次分析法,建立模糊综合评价模型,并通过我校的节能示范工程验证模型的有效性.     

系列长链烷氧基苯甲醛的合成研究

以长链正烷基醇为原料与氢溴酸作用 ,合成了长链正烷基溴 6个 ;再与对或间羟基苯甲醛反应 ,合成了烷氧基苯甲醛 9个、间烷氧基苯甲醛 8个 .由于烷基链长的不同 ,其产率为 70 %～ 94% .考察了催化剂、烷基链长、羟基位置对长链烷氧基甲醛合成的影响 .解析了各种产物的红外光谱 .     

Cs/Ir(001)吸附系统的功函数与电子转移

本文借助对真空区波函数的多能量参数函数与微分并用法和jellium球/slab模型,计算了Cs吸附于Ir(001)表面的功函数,得到了一条改善的φ-Q曲线。对于清洁表面,功函数由从前的6.6eV减小到5.84eV,后者更符合实验(～5.5eV)。在极小处,功函数由约0.2eV上升到1.02eV,而实验值是1.3eV。此外,还给出了真空势分布及jellium与slab间的电子转移随Q的变化关系。 关键词：     

Lamb wave propagation in three-layered composites

I.IntroductionThepropagationpropcrticsofLambwavesinasinglep1atchavebceninvestigatedwide1ysincel93o's,butthestudyofLambwavcsin1aycredsolidcompositesisre1ative1ynew.WuandZhuana1yzedthepropagationofLambwavcsinaso1idp1ateboundedbytwo1iquid1ayerswithidentica1thickncss.['lOntheothcrhand,L1oydandRedwoodstudiednumerica11yLambwavesinacompositeconsistingofa1iquidintcrmediate1ayerandtwosolidplates.['lInour'l,lwederivedthecharacteristicequationforLambwavesintwo-layeredsolidpreviouspaper,compositeswit…     

超声法制备PbS纳米晶

超声波辐射下,以硝酸铅、硫代乙酰胺为原料制备了PbS纳米晶,用TEM和XRD研究了聚乙二醇用量和反应时间对PbS纳米晶的影响。结果表明,超声波能抑制颗粒团聚;聚乙二醇具有良好的分散性和一维导向性。PbS纳米晶粒径较细、纳米棒长度为2μm。     

VISCOSITY BEHAVIOR OF PS／TOLUENE SOLUTION IN DILUTE AND EXTREMELY DILUTE CONCENTRATION REGION

The influences of both the volume of PS/toluene solution in the Ubbelohde viscometer and the precision of the time measuring on the viscosity behavior in dilute and extremely dilute concentration region are investigated. It was found that the influence of the former can neglect, but that of the latter is so prominent that the data fluctuate bitterly and linearity of the curve of the reduced viscosity vs. concentration (ηsp/c-c) becomes too bad to obey the Huggins equation down to the extremely dilute region, despite the error of the flow times Δt≤0.2s, which is permitted by the conventional method of viscosity measurement. Through strict mathematical analyses, it was found that the error (E) of the reduced viscosity is in proportion and inverse propor tion to Δt and concentration c, respectively. So the less the concentration, the more the error is. Consequently, a lowest concentration limit cL corresponding to given experimental error may exist and it will be meaningless for further operation below CL because of the great fluctuation of the data. Therefore, it needs to seriously reconsider the application of the conventional method of Ubbelohde viscosity measurement in the extremely dilute polymer solution under traditional conditions because of the great influence of the experimental error.     

A New and Practical Procedure for the Preparation of the Glucohexatose Phytoalexin Elicitor

The phytoalexin elicitor β-(1→3)-branched β-( 1→6)-linked glucohexatose has been regio- and stereospecifically synthesized by coupling of the 3, 6-branched gluco-trisaccharide Schmidt reagent 10 with a mixture of multiol 3,6-branched gluco-trisaccharides 13 which consists of free 5,6‘-OH trisaccharide, free 5,2‘ ,6‘-OH trisaccharide, free 5,3‘ ,6‘-OH trisaccharide and so on. The compounds 10 and 13 were prepared from 1,2:5,6-di-O-isopropylidene-α-D-glucofuranose , 2, 3, 4, 6-tetra-O-ben-zoyi-a-D-glucopyranosyl trichioroacetimldate, and 2,3,4, 6-tetra-O-acetyl-α-D-glucopyranosyl trichloreacetimidate through regio- and stereoselective manners.     

Comparison of Different Crucible Materials for the Growth of AlN Crystals

Choice of crucible material is a key issue during the growth of AlN crystal. The stabilities at high temperature and life-spans of boron nitride (BN) crucible,tantalum (Ta) crucible and tungsten (W) crucible were compared. Tantalum crucible behaved worse at high temperature and life-span was shortened as compared with the other two crucible materials. It was very crisp and easy to crack. In contrast,self-seeded AlN crystals with different morphologies could be obtained at different high temperatures using BN crucible. The boron nitride crucible was stable below 2200 ℃,above which it would decompose. Thus it was unsuitable for the bulky AlN crystal growth. Tungsten crucible could endure the temperatures higher than 2200℃. Unfortunately we could only get AlN polycrystallines using tungsten crucible. After 50～100 hours’ run,the crucible was destroyed completely due to the multiple deep cracks. XRD results of destroyed tungsten crucible indicated that the main phases are tungsten carbide and tungsten nitride.     

四氨基取代金属酞菁的光谱分析

对几种四氨基取代金属酞菁的质谱、紫外可见光谱、1HNMR谱等进行了分析,对它们的二聚现象、氨基的氧化稳定性、热力学转动稳定性和共轭稳定性(分子内氢键)进行了研究.结果表明,它们在强极性溶剂(DMF)中有二聚倾向,其分子中氨基的抗氧化性较强;外围(2位取代)氨基金属酞菁a1～a4分子上的氨基以热力学转动稳定状态为主,外围(1位取代)氨基金属酞菁b1～b4分子上的氨基以分子内氢键的形式存在,以热力学共轭稳定状态为主.