双核的

We have studied the transition metal complexes catalyzed sequential cross coupling reactions of these new difunctional group reagents with electrophiles and nucleophiles, respectively; developed some convenient and practical new methods for the stereoselective synthesis of disubstituted alkenes, trisubstituted alkenes, conjugated dienes containing heteroatom, conjugated enyne containing heteroatom etc., enriching methodologies for organic synthesis.

继而研究了这些新型双官能试剂在过渡金属配合物催化下分别与亲电试剂、亲核试剂的顺序交叉偶联反应，为双取代烯烃、三取代烯烃、杂原子取代的共轭二烯烃、杂原子取代的共轭烯炔烃等的立体选择合成提供了方便实用的新方法，丰富了烯烃立体选择合成的方法学。

The synthesized cDNA is a continuous band less than 6. 0kb shown on x-film through α〓PdCTP which was inserted in the first strain of cDNA. The titer of the Ha-cDNA library was about 1. 5×10〓cfu/ml which could represent all protein-encoding sequences from Hz-AM1 cells; Namely, the cDNA library has representativity. After the successful construction of the Ha-cDNA library, the open-reading frame of vp39 gene of Heliothis armigera was then fused in frame with the Ga14-DNA-binding domain in the pGBT9 plasmid and the fusion protein Ga14-VP39 was expressed in yeast to be used as bait protein.

在成功构建棉铃虫细胞Hz-AM1cDNA文库的基础上，本文接着将棉铃虫核型多角体病毒衣壳蛋白VP39（HaNPV-VP39）基因克隆到酵母双杂交系统(yeasttwo-hybrid system)中的质粒pGBT9上。pGBT9上含有酵母菌转录激活因子GAL4 DNA结合域的编码区（GAL4-DBD），使克隆到质粒pGBT9上的HaNPV-vp39基因与GAL4-DBD基因融合，在酵母菌中表达DBD-vp39融合蛋白，该融合蛋白即为酵母双杂交系统中的诱饵蛋白。

The ultrastructure characters of pollen grain in Brassica napus are:1There are vacuoles in cytoplasm but no starch grain in uniceelluar pollengrain.2The veget- ative nucleus of bicellular pollen grain is generally spheroidal;while the generative cell is spinde-shaped,with a big nucleus,thin layer of cytoplasmand few cell orgens,no cell wall.3In three-celled pollen grain the sperm cell is separated from the cytoplasm of vegetative cell by two layers of plasmic membrances.

Brassica napus的花粉粒，在不同发育时期超微结构的特征如下：1单胞花粉粒有一个球形的细胞核和明显的核仁，细胞质内出现液泡，缺少典型的淀粉粒。2双胞花粉粒的营养核多为球形。生殖细胞纺锤形，无细胞壁，细胞核比例大，细胞质呈薄层，细胞器少。3三胞花粉粒有一个裂片状的营养核和两个纺锤形的精细胞，精细胞无壁，以两层质膜与营养细胞的细胞质相隔。

Song behavior and its song-control nuclei (such as the robust nucleus of the arcopallium-RA) are highly sexually dimorphic in passerine songbirds.

鸣禽的发声行为及其前脑发声控制核团存在显著的性双态性，这种性双态性是在发育过程中逐步建立起来的。

The results showed that MGM had good spherical shape and narrow size distribution,and the particles with diameters ranging from 0.13 mm to 0.28 mm were about 91 wt%.The surface hydrophilicity of Fe3O4 microcrystal was improved by formamide dispersing treatment.The gel particles made by the copolymerization of glycidyl methacrylate and N,N′-methylene bisacrylamide could encapsule Fe3O4 microcrystal to produce colloid cores,and uniform and stable MGM microspheres were formed by the conglomeration of the colloid cores.

结果表明，合成的MGM呈球形，且粒度分布较窄，粒径为0.13～0.28 mm的粒子占91%；甲酰胺分散Fe3O4，微晶表面的亲水性进一步增强，单体甲基丙烯酸缩水甘油酯和 N，N′亚甲基双丙烯酰胺交联共聚生成的胶粒能够包埋Fe3O4微晶形成胶核，胶核聚集形成均匀、稳定的MGM微球。

Using the high performance MRI scan is the reliable method of studying the cerebrum internal tissue's asymmetry;The cerebrum internal tissue(two sides of caudate nucleus、lentiform nucleus and lateral ventricle) are roughly symmetric,they don't exit obviously difference.

结论利用高性能的MRI仪器扫描测量可以作为研究大脑相关结构的可信赖的方法；大脑内部结构(双侧尾状核、豆状核及侧脑室)是基本对称的，不存在明显的侧别差。

Olefine, electrophilic or nucleophilic substitution of arenes, nucleophilic addition of carbonyl compounds stereochemistry in elimination reaction of double bond forming and the choosing of oxidants and reducing agents in redox system.

在化学反应方面重点是烯烃的亲电加成，芳香烃的亲电，亲核取代，羰基化合物的亲核加成，消除反应的双键定位和立体化学，氧化，还原反应中氧化还原剂的选择。

The source,existing form and equilibrium of carbonic acid in natural water are presented in this article,which points out that alkalinity is determined by double indicator that indicates purply at the first terminal point,while at the second terminal point should use methyl red-bromocresol green mixed indicator.

介绍了天然水体中碳酸的来源、存在形式及平衡关系；指出用&双指示剂&法测定水中碱度的第一终点应显粉紫色，第二终点宜采用甲基红-溴甲酚绿混合指示剂；测定游离二氧化碳要用双样测定并严格控制滴定终点；各种碳酸的含量可与pH值、硬度的测定结果进行校核。

Experimental study on effect of acetic acid and carbonic acid on clay's geotechnical behaviors;2. The source,existing form and equilibrium of carbonic acid in natural water are presented in this article,which points out that alkalinity is determined by double indicator that indicates purply at the first terminal point,while at the second terminal point should use methyl red-bromocresol green mixed indicator.

介绍了天然水体中碳酸的来源、存在形式及平衡关系；指出用&双指示剂&法测定水中碱度的第一终点应显粉紫色，第二终点宜采用甲基红-溴甲酚绿混合指示剂；测定游离二氧化碳要用双样测定并严格控制滴定终点；各种碳酸的含量可与pH值、硬度的测定结果进行校核。

The planishing mill designed adopts a framework with an initiative driving system with double dynamoelectric machine, enclosed type of machine frame, fluid-pressure system and so on. As a focal point, this paper has discussed the design calculation for the planishing mill, including: structure parameter of a rolling mill, initiative driving system, choose for dynamoelectric machines, a design for fluid-pressure system, a determination for the size of the machine frame and its intensity checking, roller design and its intensity checking, life-span of the bearings and so on.

设计的平整机主要采用了双电机主传动传动系统、闭式机架，液压压下系统等机构；本论文着重在于研究了平整机的设计计算，具体包括：轧机的结构参数设计计算、主传动力能参数设计计算及电机的选择、液压压下系统设计、机架尺寸确定及其强度校核、轧辊设计和强度校核、轴承的寿命计算等。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。