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Heteroduplex molecules have been made by mixing pJSA1175 and pJSAl175ADRV4, pJSA1175ADRV4 and pJSAl175RRV4 DNA molecules which have been linearized by Pst Ⅰ and Bgl Ⅱ respectively, denaturing them in alkaline or high temperature, allowing them to renature and then spreading in the presence of formamide.

以痘苗病毒表达载体pJSA1175及重组质粒pJSA1175ADRV4(含ADRV VP4基因)、pJSA1175RRV4(含猴轮状病毒VP4基因)为材料，用碱变性方法或热变性方法制备了载体质粒与重组质粒DNA之间的异源双链，电镜下成功观察到载体序列部分经变性、复性后配对呈双链状态，而外源基因区域突出呈单链环状结构，测量长度为2.3kb。

The influences of the type and dosage of the aldehyde, organic acids, as well as the water content in the reaction system on the racemization were examined in detail, and L-Glu was racemized quickly in the presence of 0.2 molar ratio of L-Glu to salicylaldehyde in acetic acid containing 20% water.

详细考察了腔的种类及用量、羧酸溶剂的种类、反应体系的含水量对消旋化的影响，结果表明L谷氨酸在含20%水的乙酸溶剂中，以水杨醛作为催化剂（水杨醛与L-谷氨酸的物质的量比为0.2）的优化条件下可以快速地被消旋化。

The hydrothermal synthesis of small crystal silicious ZSM-5 zeolite in the presence of cheap template was studied in this paper.

ZSM-5沸石是一种极其重要的分子筛催化材料。通过调节骨架硅铝比和晶体粒度可以有效地调节ZSM-5沸石的催化性能。

A micro-monolithic column was prepared by in-situ free radical polymerization of stearyl methacrylate with ethylene glycol dimethacrylate in the presence of the initiator AIBN and a mixture of porogens including iso-amyl alcohol and 1,4-butanediol.

以甲基丙烯酸碳酰十八酯为单体，乙叉二甲基丙烯酸酯为交联剂，异戊醇和1，4-丁二醇为二元致孔剂，偶氮二异丁腈为引发剂，原位制备了具有强疏水性的SMA整体微柱，并利用此整体微柱在普通高效液相色谱仪上测定滴眼液中氧氟沙星的含量。

In the presence of DMSO as co-solvent and under vigorous agitation, baker\'s yeast in water was found to reduce substituted fluorenones to the corresponding fluorenols in good to excellent enantioselectivies (52%~ 100% ee). The experimental results clearly revealed that when mass transfer limitations are overcome, baker\'s yeast is able to reduce even highly sterically hindered ketones, such as substituted fluorenones.

在强烈的搅拌、并使用DMSO作为底物助溶剂的反应条件下，面包酵母对取代芴酮显示出较高得还原活性，得到立体选择性很高的相应的芴醇(52%～100%ee)。

A series of 3,3,6,6 tetramethyl 1,8 dioxo 9 aryl 1,2,3,4,5,6,7,8,9,10 decahydro acridines have been synthesized by the condensation of aromatic aldehydes, 5,5 dimethyl 1,3 cyclohexanedione and ammonium acetate in the presence of triethylbenzylammonium chloride as catalyst in water.

芳醛、5 ，5 二甲基 1，3 环己二酮与醋酸铵在三乙基苄基氯化铵催化下以水作为溶剂反应，生成一系列 3 ，3 ，6，6 四甲基 1，8 二氧代 9 芳基 1，2 ，3 ，4，5 ，6，7，8，9，10 十氢吖啶，与其它溶剂相比，水作为该反应的溶剂具有价格便宜，不易燃和无毒等优点，而且产率较高，产物的结构通过单晶X射线确

Pyrolytic methylation of G. biloba leaves in the injector at 300℃ in the presence of an organic alkali, tetramethylammonium hydroxide (TMAH, 25% methanol), allowed quantitative analysis of ginkgolic acids as their corresponding methyl derivatives.

银杏叶样品与衍生化试剂四甲基氢氧化铵（TMAH，25%甲醇溶液）同时进样，在300℃的进样口瞬间生成了银杏酸甲基衍生物，银杏叶中6种银杏酸得到很好的分离。

DPODPS with melting point within three degrees can be obtained,purified by recrystal.2, 4,4\'-diphenyoxy-diphenyl sulfone was synthesized by reaction of phenol with bis (4-chlorophenyl)sulfone in tetramethylene sulfone in the presence of NaOH.

将其在亲电反应条件下和对苯二甲酰氯或间苯二甲酰氯共缩聚制得了二种聚芳醚砜醚酮酮树脂，用IR、DSC、TG、WAXD等对其结构和性能进行了表征，同时研究了聚合物在300±10℃空气中的氧化热稳定性。

In this paper a series of multiblock copolymers were synthesized by polycondensation of poly , phthalic anhydride and epoxy resin in the presence of triethyl benzyl ammonium chloride as the catalyst.

以三乙基苄基氯化铵为催化剂，将聚乙二醇、邻苯二甲酸酐和环氧树脂进行共缩聚，制得聚乙二醇-环氧树脂系列多嵌段共聚体。

In chapter 4, we have described an improved method for the preparation of ethynylferrocene. Ethynylferrocene was prepared in satisfactory yield by reaction of formylferrocene with triphenylphosphine and carbon tetrachloride followed by dehydrohalogenation in the presence of n-BuLi.

第三章中，我们研究了钯催化下碘杂环化合物的羰基化—酰胺化反应、羰基化—酯化反应和与末端炔烃的羰基化交叉偶联反应，为一步合成多官能团化合物开辟了新的途径，同时，得到的这些产物经过进一步官能团转化后，可以成为一些天然产物合成中的重要中间体化合物。

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。