Two Typical Examples of Scaling Ionic Partition Scheme for Estimating Correlation Energy of A2 Type Molecules

Based on the calculation results of pair correlation energy contributions of the various electron pairs in Na2 and H2NNH2 systems and the application of the scaling ionic partition scheme for symmetrical A2 type systems, the total correlation energies of Na2 and H2NNH2 have been reproduced by using this simple scheme. The two results show that the absolute deviations are within an acceptable range of error, however, in this way, more than 90% of computational work can be saved. The most attractive result in present paper is that, in these two molecules the coefficients c1 and c2 in the estimation equation can be obtained by the proportion of correlation energy of A^- to that of A^ singlet system. Therefore, it is believed that the proposed ionic partition scheme for symmetrical A2 molecules would be very useful to estimate the correlation energies of large symmetrical molecules.     

α—胰凝乳蛋白酶的固定化及其对DL—苯丙氨酸的光学拆分

以氨丙基多孔球为载体，戊二醛为交联剂制得固定化α－胰凝乳蛋白酶。其含酶量为３．６ｍｇ／ｇ，米氏常数Ｋｍ＝１．２×１０＾－３ｍｏｌ／Ｌ，最适宜温度为３５℃，ｐＨ值为７．０，对热、酸碱、甲醇以及尿素的稳定性有较大提高，Ｃａ＾２＋激活效应明显。用该固定化酶连续拆分ＤＬ－苯丙氨酸制备Ｌ－苯丙氨酸时，拆分产率高于９０％，产品纯度超过９６％；连续使用２个月后仍能保持较高酶活力。     

Study on Pair Correlation Energies of Isoelectronic Systems F~-,HF and H_2F~+

IntroductionAsawell knownfact ,thecalculationofelectroncor relationenergyisabottleneckprobleminthecalculationsofmolecularpropertiesandchemicalreactionsinquantumchemistry .1Ithasattractedgreatattentionoftheoreticalchemists.NumerousdifferentmethodshavebeenusedtocalculatethecorrelationenergysinceL wdin2 givethedef initionofelectroncorrelationin 195 9.In 196 0s ,Sinanoˇglu3,4 definedtheexactelectronpaircorrelationen ergyanddevelopedmany electrontheoryofatomsandmoleculesinwhichthetotalcorrelation…     

退火处理提高P3HT:PCBM聚合物太阳能电池光伏性能

利用旋转涂膜方法制备了以P3HT:PCBM为有源层的聚合物太阳能电池, 器件结构为ITO/PEDOT:PSS/P3HT:PCBM/Al(氧化铟锡导电玻璃/聚二氧乙基噻吩:聚对苯乙烯磺酸/聚三已基噻酚:富勒烯衍生物/铝),研究了退火温度对聚合物太阳能电池性能的影响. 实验发现: 聚合物薄膜经过120 °C退火10 min处理后, 开路电压(V_oc)达到0.64 V, 短路电流密度(J_sc)为10.25 mA·cm^-2, 填充因子(FF) 38.1%, 光电转换效率(PCE)达到2.00%. 为了讨论其内在机制, 对不同退火条件下聚合物薄膜进行了各种表征. 从紫外-可见吸收光谱中发现, 退火处理使P3HT在可见光范围内吸收加强且吸收峰展宽, 特别是在560和610 nm处的吸收强度明显增大; X射线衍射(XRD)结果表明, 120 °C退火后P3HT在(100)晶面上的衍射强度是未退火薄膜的2.8倍, 有利于光生载流子的输运; 原子力显微镜(AFM)研究结果表明, 退火显著增大了P3HT与PCBM的相分离程度, 提高了激子解离的几率; 傅里叶变换红外(FTIR)光谱验证了退火并没有引起聚合物材料物性的变化.     

食品中合成色素快速检测仪器的研制

基于人工合成色素在可见光区的光吸收及偏最小二乘变量筛选法,研制出合成色素速测仪器,并应用于饮料、糖果、果冻、调色酒等食品中合成色素的快速检测.速测仪具有便携、功耗低、操作简便、检测时间短并可同时对多种人工合成色素进行实时现场快速检测、检测结果准确等优点.对样品中5种食用合成色素柠檬黄、日落黄、胭脂红、苋菜红和亮蓝的检测...     

Surface Modification of Silica Gels as Carrier for AminoacylaseImmobilization

IrnmobilisedaIninoacylaseisanotablecatalystforthekineticresolutionofN-acetyl-D,L-aIninoacidsandquitealotofresearchworkhasbeeninvolvedonaminoacylase~bilisationswithitscarriers.lTheauthorshaverePortedthattheaIninosilicagelspreparedbyanlinProvedmethodwereeffechveforchymotryPsininunobilisahon,'l'butitwasnotproperforaIninoacylasetriobilisahon.InordertodevelopasahsfactorysurfacesmictUreofsilicagelsforaIninoacylasetriobilisation,tWokindsofreactivegrouPs,theN,N-diethylaIninogrouPandthehydroxygr…     

我国首张“5.1声道DVD质量样板试机碟(第一版)”出版发行

我国是DVD播放机和家庭影院放大器、扬声器系统的生产和消费大国。据有关行业协会统计,我国国产DVD播放机一年的销量达到3000万台,各种大大小小的国产家庭影院放大器超过700万台,国产扬声器系统则达1000万套以上,加上在我国销售的外国产品,我国消费者购买的数量则更为可观。     

PLZST反铁电陶瓷电场诱导相变与相稳定性的研究

在三方铁电(FE)-四方反铁(AFE)的准同型相界附近制备了一系列组份为(Pb_0.97La_0.02)(Zr_1-x-ySn_yTi_x)O₃(x=0.09或0.1;0.16≤y≤0.38)的反铁电陶瓷.研究了Sn含量y对电场诱导AFE→FE相变电场E_c、反铁电双电滞回线损耗ΔE、以及温度诱导FE→AFE相变温度T_FE，AFE→顺电(PE)相变温度T_c的影响.沿AFE-FE相界Ti含量一定的条件下，E_c随着Sn含量y的增加而增大，ΔE减小，T_FE与T_c均降低.场诱相变的回线参量E_c，ΔE与相变温度T_FE和T_c相关联.在直流偏压下用原位X-射线衍射表征了相变时晶格结构的变化，结果表明，当电场达到AFE→FE相变临界场时，伴随相变的发生，晶格结构由四方相转变为三方相，晶胞体积增大. 关键词：     

A Weighted Evolving Network with Community Size Preferential Attachment

Community structure is an important characteristic in real complex network. It is a network consists of groups of nodes within which links are dense but among which links are sparse. In this paper, the evolving network include node, link and community growth and we apply the community size preferential attachment and strength preferential attachment to a growing weighted network model and utilize weight assigning mechanism from BBV model. The resulting network reflects the intrinsic community structure with generalized power-law distributions of nodes＇ degrees and strengths.     

煤的清洁利用技术的现状与发展

文章针对中国一次能源以煤为主的特点,深入分析了几种主要的煤的洁净利用技术的现状及存在的主要问题和发展趋势,其中包括大容量、高参数的超(超)临界燃煤发电技术、燃煤烟气净化技术、循环流化床燃烧技术(CFBC)、整体煤气化联合循环技术(IGCC)和煤的洗选技术.在此基础上,给出了中国煤的清洁利用方式的建议:近期仍以超(超)临界燃煤发电机组+燃煤烟气净化技术和循环流化床燃烧技术为主;整体燃气化联合循环技术、富氧燃烧技术(特别是加压富氧燃烧技术)以及二氧化碳的捕集和封存技术(CCS),具有广阔应用前景,值得长期大力发展.