Purification and Inhibition Fungal Growthof Chitinases from Vibrio pacini

0　IntroductionChitinases (EC3.2 .1.14 )areenzymesthathydrolyzechitin ,ahomopolymerofβ 1,4linkedN acetylglucosamine .Thecompletedegradationofchitinchainsisusuallyachievedbyacom plexofenzymesactingtobreaktheinitialchainsintochitooligosac charides .Theseparateenzymesthenacttobreaktheseoligomersdownintotheircomponentmonomers.Thechitinolyticsystemex istsinawiderangeoforganisms,includingbacteria[1 ] ,fungi,higherplants[2 ] ,insects[3] ,crustaceans[4] andsomevertebrates,andplaysvariousrolesbothin…     

水星近日点进动的广义相对论证明

用史瓦西度规详尽地推导了太阳引力场,用广义相对论解释了水星近日点的进动。     

Observation of contrast variations of a copper (Ⅱ) complex by scanning tunneling microscopy

This report presents experimental observations of dramatic variations in STM images of bis [1,3-DI(p-n-tetradecyloxyphenyl)propane-1,3-dionato]copper( Ⅱ） (abbreviated to C14O-Cu)physisorbed on HOPG as the bias voltage is changed .Several representative image patterns were obtained for the rich changes of the internal contrast of the molecule .Submolecular features of the molecular cores and the interdigitated alkyl parts are clearly visible.     

2D self-assembling of 4, 5-didodecylthiolphthalonitrile on graphite surface

An important precursor 4,5-didodecylthiolphthalonitrile (DCP) for synthesis of phthalocyanines (Pcs) and subphthalocyanines (SubPcs) was synthesized and the assembling structure of this molecule on the basal plane of highly oriented pyrolytic graphite (HOPG) surface was characterized using the scanning tunneling microscopy (STM) in ambient conditions. In high-resolution images of the molecules, we found that the arrangement of the cyano groups forms a “head-to-head” configuration to keep the stability of the entire system. The mismatch of the DCP molecules with the substrate lattice has also been observed in the experiment.     

Assessing Fabrics Wrinkling by Image Analysis

In this paper, the features of fabric wrinkle structure are analyzed, by image processing technique. The wrinkle images are processed and character parameters are extracted. The wrinkle side surface area ratio of image gray level intensity, the standard deviation of total pixels' gray level intensity and the standard deviation of wrinkle block area are adopted to evaluate fabric wrinkling. The results show that these three character parameters can be served for ranking the wrinkling. It provides a feasible objective method for fabrics wrinkling degree assessing.     

实验性交感性眼炎发病机制的研究

以13只白色豚鼠作实验,其中3只为 C 组作对照,另10只分为 A、B 二个组,在以牛晶体蛋白连续皮内注射4次致敏之后,做一只眼的晶体截囊术。术后 A 组皮下注射生理盐水,B 组则皮下注射环孢霉素(Cyclosporine)。结果 A 组发生交感性眼炎,而 B 组和 C 组均未发生。因为环孢霉素具有选择性的抑制 T 淋巴细胞的功能,故推测交感性眼炎的发病机制可能与 T 淋巴细胞的关系极为密切。     

Economic Development and the QPMSLP of the Industrial Allocation of Foreign Capital

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齿轮系统随机振动及其传动误差的可靠性及灵敏度分析

基于齿轮动力学模型建立了齿轮传动系统耦合振动的可靠性模型,解决了齿轮耦合振动的可靠性分析和可靠性灵敏度分析的问题.将齿轮系统的非线性动力响应与可靠性技术相结合,利用四阶矩技术、Edgeworth级数方法对齿轮振动的振幅响应和系统传递误差进行了可靠性分析,并基于失效模式相互独立分析了系统的可靠度.在可靠度分析基础上求解了可靠度对随机参数均值与方差的灵敏度.所述方法可有效地解决齿轮系统的振动可靠性问题,并可指导其结构的优化设计,以减少因振动引起的齿轮系统传动的不稳定性问题.     

细菌内毒素对基因免疫小鼠存活率和产仔率的影响

作为第三代疫苗,核酸疫苗具有易操作、低成本等优点,但是其内在危险性还有待进一步研究和排除,在其制备过程中可能掺入的细菌内毒素就是影响因素之一.细菌内毒素是革兰氏阴性菌细胞壁外膜结构中的脂多糖,体内释放后会引起发热、休克等多种病理变化.国外已有体外实验证明内毒素会对小鼠的生殖系统产生影响,本研究旨在通过在体实验探讨内毒素对免疫小鼠的存活率和产仔率的影响.采用常规方法(碱裂解法)、试剂盒2种方法,提取2种pCR3.1-Sry质粒(2种质粒的区别在于是否去除内毒素,其浓度和纯度均经过琼脂糖凝胶电泳和紫外分光光度法分析和控制).作为核酸疫苗对小鼠进行免疫:全程统计免疫小鼠的存活率和产仔率,同时注射灭菌ddH2O作为对照.分子生物学实验结果显示,所制备疫苗具有适宜的浓度和较高的纯度;免疫实验和数字统计结果显示,未去除内毒素实验组小鼠较去除内毒素组的存活率由93%下降到84%、产仔率由87.5%下降到35.7%,而去除内毒素组却与对照组没有明显差异.总之,核酸疫苗制备过程中掺入的细菌内毒素会对免疫小鼠造成较大不良影响,特别是生殖系统,体现在产仔率大幅降低.     

蟠龙油田F110井区延长组储层微观非均质性模拟

通过真实砂岩微观孔隙模型实验.对储层内油、水两相流体的微观渗流机理进行模拟,以求更深层次地了解研究区延长组砂岩储层的微观非均质性及其对剩余油分布的影响.分析认为,研究区延长组储层的微观非均质性很强,且存在储层物性越好,其微观非均质性越强的特点,成岩作用和孔隙结构是影响微观非均质性的主要因素.实验表明,微观非均质性是影响水驱油效果和剩余油形成的内因.在充分认识研究区延长组砂岩储层4种主要孔隙类型的基础上,根据实验结果,建议相应地制定3类注水开发方案,剩余原生粒间孔隙型和次生溶蚀孔隙型归为一类,微裂缝型一类,自生矿物晶间微孔隙型一类.