锯链传动链片的有限元分析

用有限元法对锯链的传动链片进行了应力分析，结果表明：危险剖面上的应力分布是不均匀的，在运转中传动链片所受的应力为变应力，按传统的方法仅计算静强度是不够的，要提高锯链的使用寿命，必须提高锯链零件的疲劳强度。     

应用RT／PCR—SSCP法分析传染性法氏囊病病毒的变异性

根据传染性法氏囊病病毒（IBDV）cDNA序列，在病毒VP2区域设计1对引物，应用RT／PCR－SSCP方法对4个不同时间及不同地域从传染性法氏囊病（IBD）病鸡法氏囊组织中分离的IBDV分离物进行了分析，发现4个IBDV分离物的SSCP图谱均存在明显差异，本试验表明，IBDV变异在我国普遍存在，SSCP方法可用于IBDV的变异性分析。     

Nested PCR检测微量隐孢子虫卵囊

根据隐孢子虫18SrDNA序列，设计出隐孢子虫属和鼠隐孢子虫种的特异性引物，进行PCR和Nested PCR反应，先后分剐扩增出1条540bp和1条250bp的条带。研究表明，NestedPCR具有高度的特异性和敏感性。应用NestedPCR可检测1～10个鼠隐孢子虫卵囊，其敏感性是饱和蔗糖漂浮法的10^5倍以上。     

物流空间信息组织体系的构架研究

物流管理是供应链管理的核心,是制造企业迅速组织生产的关键。基于供应链上的各种对象与G IS的关系,指出了物流技术与空间信息技术融合成物流空间信息技术的必然性;提出了采用总线型G IS模型作为物流空间信息系统的结构模型,并由此进行物流空间信息的组织体系的构架设计,该构架充分利用了中间件热插拔的特性,能够很好地满足物流空间信息所涉及的异构分布式复杂信息集成要求。     

全脂大豆对肉仔鸡粗蛋白代谢率影响的研究

采用生、熟全脂大豆和对照日粮分7组饲喂出壳1日龄艾维茵（Arian)肉仔鸡，研究生、熟全脂大豆对肉仔鸡粗蛋白代谢率的影响。结果表明：饲粮粗蛋白（CP）代谢率在试验前、后期饲喂生大豆饲粮的肉仔鸡显著低于饲喂熟大豆和后期饲喂对照饲粮的肉仔鸡（P＜0．01）。     

A polymerase chain reaction (PCR) assay for the detection of bovine herpesvirus 1 (BHV1) in selectively digested whole bovine semen

A PCR assay for the detection of bovine herpesvirus type 1 (BHV1) DNA in selectively digested whole bovine semen was developed and evaluated. A brief treatment with proteinase-K was used to lyse free virus, virus present in non-sperm cells and virus adhering to the spermatozoa. Genomic bovine DNA was not released by this treatment. Primers and probes were based on the nucleotide sequence of the gD gene. BHV1 virus-spiked split samples were used as positive controls and the PCR products were detected by eye in ethidium bromide-stained agarose gels. Sequentially collected non-extended semen samples from experimentally infected bulls were used to compare this assay with virus isolation. Of a total of 162 ejaculates, 51 were found positive by virus isolation, whereas PCR detected BHV1 DNA in 73. PCR detected BHV1 DNA for a longer period after infection and reaction. Apart from its superior sensitivity, this PCR assay also has the advantage of being a relatively simple procedure, providing results within 24 h.Abbreviations AI artificial insemination - BHV1 bovine herpesvirus type 1 - PCR polymerase chain reaction - TCID₅₀ tissue culture infective dose, 50%     

Establishment of Embryo Sexing Techniques in Sweden*

The establishment of some invasive techniques for bovine embryo sexing such as direct chromosomal evaluation, in situ hybridization using Y-specific probe, and polymerase chain reaction for a Y-specific DNA sequence is briefly reported. Advantages and disadvantages for their practical use are mentioned.     

锯链连接片偏磨原因的受力分析及解决途径的研究

通过对国内外万能锯链负荷工作时的受力分析,发现现有万能锯链的切齿组件的设计几何参数不尽合理。因而,造成正压合力集中,促使连接片偏磨,缩短了锯链寿命。同时,偏磨后的切齿组件切削功能恶化,影响了链锯机械性能的发挥。为此,重新设计了切齿组件,使正压合力趋向多点均匀分布。经生产、台架试验证明,新型锯链的使用寿命,是国产锯链的2倍左右,是斯蒂尔锯链的1.5倍;切削效率比国产锯链提高35—116.7％,比奥利根锯链提高3—4％。同时,切齿组件在整个生产过程中,始终保持着良好的切削状态和原设计的主要几何参数。证明“正压合力多点均匀分布”的设计理论是克服连接片偏磨的可靠途径。     

Bioaccumulation of Butyltins via an Estuarine Food Chain

An estuarine food chain of threetrophic levels–algae (Platymonas sp.), rotifers (Brachionus plicatilis) and mysids (Neomysis awatschensis Brandt) was setup in laboratory in order to investigate contributionsof water and food to the accumulation of butyltins inupper trophic organisms, as well as to evaluate thelikelihood of biomagnification of butyltins throughthe aquatic food chain. Kinetics of bioaccumulationand depuration of butyltins through the food chainwere studied. Bioconcentration factors of butyltins inthe three organisms were high (10³–10⁴).Butyltin burdens in the upper trophic organisms atsteady-state of bioaccumulation by the ingestion oftainted food exceeded those observed by exposure towater only. For total butyltins, food chain transfernumber was 1.44 for algae to rotifers and 0.59 forrotifers to mysids, respectively. Biomagnification wasnot confirmed. It is concluded that whether or notbiomagnification occurs depends not only on theproperty of compounds but also on the organisms involved.     

Contribution of the polymerization of protein by disulfide bonding to increased gel strength of walleye pollack surimi gel with preheating time

ABSTRACT: To clarify the contribution of polymerization of myosin heavy chain (MHC) by disulfide bonding to increased gel strength of cooked gel via preheating, the pastes of walleye pollack surimi (SS and C grades) were preheated at 25°C and 40°C for a variety of hours prior to heating at 80°C for 20 min. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) patterns of cooked gels were analyzed with and without reducing the samples, which were solubilized in 8 M urea–2% SDS solution. The formation of polymers by disulfide bonding in cooked gels was almost constant in each of the SS and C grade surimi gels despite the period of preheating. Therefore, it was suggested that polymerization by disulfide bonding occurred during cooking at 80°C and not during preheating.