Epitaxial recrystallization of HDPE-quenched ultrathin films on oriented iPP substrates

The recrystallization behavior of high-density polyethylene (HDPE) on the highly oriented isotactic polypropylene (iPP) substrates at temperatures below the melting temperature of HDPE has been investigated by means of transmission electron microscopy. The results obtained by the bright-field observation and the electron diffraction show that upon annealing the HDPE-quenched films on the oriented iPP substrates at temperatures below 125 degrees C, only a small amount of HDPE recrystallizes on the iPP substrate with [001](HDPE)//[001](iPP), while annealing the HDPE-quenched films at temperatures above 125 degrees C, all of the HDPE crystallites recrystallize epitaxially on the iPP substrate with [001](HDPE)//[101](iPP). (C) 1997 John Wiley & Sons, Inc.

Stereochemical effect in mass spectrometry .19. Determination of the optical purity of alpha-phenylethylamine by mass spectrometry

It is found that in the fast atom bombardment (FAB) mass spectra R-alpha-phenylethylamine and S-alpha-phenylethylamine can be clearly distinguished by S-1,1'-binaphthyl-2, 2'-diylhydrogenphosphate (S-BNP), Mixture of R-alpha-phenylethylamine and S-alpha-phenylethylamine also be tested and the relative abundance of the characteristic ion of mixture is related to the composition of the mixtute. We have therefore proposed a possible method to determine the optical purity of alpha-phenylethylamine.

质谱中的立体化学效应（19）──对映异构的α－苯乙胺光学纯度质谱测定

质谱中的立体化学效应（１９）──对映异构的α－苯乙胺光学纯度质谱测定吴忆南，涂亚平，潘远江，陈耀祖（浙江大学化学系，杭州，３１００２７，兰州大学应用有机化学国家重点实验室）崔勐，宋凤瑞，刘淑莹（中国科学院长春应用化学研究所）关键词对映体，光学纯度，质...

Meldola拉蓝修饰双层类脂膜的电化学研究

双层类脂膜(BLM)作为生物膜的基本结构主体已被广泛接受。通过掺杂和化学修饰可以改变BLM的特性,并能应用于多种生物膜过程的研究。特别是制成生物传感器和双分子电子器件将有广阔的应用前景。多种有机染料被称作生物着色剂并常用于生物学、生理学、药物学和医学。一般来说,染色和着色过程包括吸附、溶解、渗透和化学反应。但染料如何影响磷脂膜仍然不十分清楚。本文选用用于生物传感器中的生物催化剂Meldola蓝来修饰BLM,并对它的传输性质进行了分析。

含联苯结构侧链液晶聚合物的合成及相行为的研究

液晶聚合物从结构上可分为3种:侧链型、主链型和主侧链型。侧链型液晶聚合物主要是聚丙烯酸酯类、聚硅氧烷类以及磷腈聚合物类。Gray等对聚丙烯酸酯类含不同取代基的联苯结构液晶聚合物进行了研究,结果表明无间隔基且取代基为氰基和饱和脂肪基时,该聚合物呈现近晶型液晶行为。为了增加介晶单元的长径比及刚性,本文在聚甲基丙烯酸酯侧链

Molecular cloning and characterization of a thioester-containing protein from Zhikong scallop Chlamys farreri

Thioester-containing proteins are a family of proteins characterized by the unique intrachain beta-cysteinyl-gamma-glutamyl thioester, which play important roles in innate immune responses. The cDNA of Zhikong scallop Chlamys farreri thioester-containing protein (designated as CfTEP) was cloned by expressed sequence tag (EST) and rapid amplification of cDNA ends (RACE) approaches. The full-length cDNA of CfTEP was of 4616 bp, consisting of a 5 '-terminal untranslated region (UTR) of 30 bp and a 3 ' UTR of 140 bp with a polyadenylation signal sequence AATAAA and a poly(A) tail. The CfTEP cDNA encoded a polypeptide of 1481 amino acids with the theoretical isoelectric point of 5.98 and the predicted molecular weight of 161.4 kDa. The deduced amino acid sequence of CfTEP contained the canonical thioester motif GCGEQ, nine potential N-glycosylation sites and a C-terminal distinctive cysteine signature. It also contained a presumed catalytic histidine and proteolytic cleavage sites that were similar to C3 molecules. The high similarity of CfTEP with the thioester-containing proteins in other organisms, such as the TEPs from insects, the complement component C3, C4, C5 and the protease inhibitor alpha(2)-macroglobulin indicated that CfTEP should be a member of TEP family. The phylogenetic analysis revealed that CfTEP was closely related to TEPs from mollusc, nematodes and insects, and they formed a separate branch apart from the branches of complements factors and alpha(2)-macroglobulins. The spatial expression of CfTEP transcripts in healthy and bacterial challenged scallops was examined by semi-quantitative RT-PCR. The CfTEP transcripts were mainly detected in the tissues of hepatopancreas and gonad, and remarkably up-regulated by Microbial challenge, which suggested that CfTEP was a constitutive and inducible acute-phase protein involved in immune defense. These results provided new insights into the role of CfTEP in scallop immune responses, as well as the evolutionary origin of this important, widespread and functionally diversified family of proteins. (c) 2007 Published by Elsevier Ltd.

哺乳动物种群系统时空变异性透视

综述了数学和统计学对哺乳动物种群系统生态学过程与环境随机过程交互作用的研究进展，以及种群波动同步性的Moran原理及效应。自然种群最普遍的现象是其数量在时间和空间上的变异性。在不同种群之间，种群大小的波动方式存在显著的差异。阐明和理解这种差异，探讨其随环境条件而改变的潜在规律，是种群和群落生态学的主要挑战之一。种群变异性存在空间分量，在相对大的距离内，种群的波动常同步发生。对种群内部密度制约过程与诸如环境变异性等外部因子交互作用的检验正在成为哺乳动物种群系统生态学领域关注的论题。

Pollen morphology and its in systematic and ecological significance in Rheum (Polygonaceae) from China

Pollen morphology of 40 species of Rheum, belonging to eight sections, was investigated under LM and SEM. Four new exine patterns were found in the species: a) microcchinate-foveolate, b) rugulate, c) verrucate-perforate, and d) verrucaterugulate ornamentation. In addition, two patterns, the Rheum-type pollens with microechinate-perforate and fine-reticulate, as previously described, were also confirmed in the present study. Based on above study the evolution trends of pollen morphology in the taxa involved were discussed phylogenetically as below. As microechinate-perforate exine pattern existed commonly, the pattern is, therefore, regarded as the most primitive among all the six types. The fine-reticulate type was thought as a derivative type, deriving from the basic micro echinate-foveolate-perforate pattern, and followed by the rugulate and verrucate-perforate ornamentation. The verrucate-rugulate ornamentation should be the most advanced. More than one pollen type often exist in most of the sections in Rheum. The pollen morphology of Rheum was strongly correlated with its geographical and ecological distribution. Three medicinally important species R. officinale, R. palmation and R. tanguticum can be palynologically distinguished by their ornamentations.

遥控设备中的抗干扰问题

遥控设备研制的过程是克服干扰的过程，作者成功地采用了降低单片机主振频率、利用单片机的待机省电状态功能、加设带通滤波器、采用光电隔离器件及各种屏蔽接地等措施研制成功了一套设备，遥控命令传输距离超过了原设计要求。

敏捷制造:高技术产业化之路

“敏捷制造”是指企业能抓住瞬息即逝的机遇，快速推出高性能、高可靠性及顾客能接受的价格的新产品的能力。在敏捷制造企业中，有创新能力和经验的员工是企业的主要财富。敏捷制造为高新技术产业化开拓了生产规模与市场规模开拓同步增长的可行道路，又在企业与用户之间建立起崭新的“战略”依存关系。

乌鲁木齐河源1号冰川表层雪的化学特征——以低分子有机酸和无机阴离子为例

表层雪是联系大气成分与冰芯记录的重要纽带,是研究成冰作用过程中化学组成变化的起点.为配合天山乌鲁木齐河源1号冰川成冰作用过程中化学组成变化的研究,对1号冰川积累区(海拔4130 m)一个完整年度的表层雪样品进行了低分子有机酸和无机阴离子含量的分析.结果显示:表层雪中低分子有机酸主要有HCOO-、CH3COO-、C2H5COO-和(COO)22-,无机阴离子主要有F-、Cl-、NO2-、NO3-、SO42-和PO43-.除(COO)22-外,大部分高浓度的有机酸…

贵阳市表层土壤中汞的环境地球化学基线及污染研究

以土壤环境地球化学研究为主线,在贵州省贵阳市8 046 km2研究区域中,将土壤重金属元素汞的空间分布规律与环境地球化学机理研究相结合,建立区域土壤环境地球化学基线,选用合适的判别指标判识自然作用过程与人类活动过程对土壤环境的影响,对487个样品的汞含量进行了统计分析.结果表明,贵阳市表层土壤中重金属元素汞的基线值为0.045 mg·kg^-1,样品中汞元素含量大于0.530 mg·kg^-1的样品可能遭受人为污染的影响.地质累积指数分析结果显示,贵阳市12%的表层土壤未受汞的污染,37%的表层土壤在无污染到中度污染之间,36%的中度污染,11%的表层土壤介于中度污染到强污染之间,2%的强污染,1%的介于强污染到极强污染之间.污染程度指数分析显示,贵阳市56.1%的表层土壤未受到汞的污染,汞的污染程度最大为45.87,总污染程度大于0（即受到污染）.

Ferrugem da mandioca.

Historicamente a ferrugem da mandioca, causada pelo fungo Uromyces manihotis Henn. não tem sido considerada uma doença importante para o Brasil. Todavia, nos últimos dois anos, severas epidemias têm sido detectadas em diferentes regiões do Nordeste brasileiro como Aracaju, no Estado de Sergipe, e São Miguel das Matas, Tancredo Neves, Porto Seguro e Ilhéus, no Estado da Bahia. No Extremo Sul da Bahia a doença foi encontrada com alta intensidade nas variedades Caravela e Platina.