Diehloromethyl biphenyl was synthesized through chloromethylation of biphenyl , starting with biphenyl and paraformaldehyde as raw materials , zinc chloride / h2o as catalyst in the presence of hydrogen chloride 摘要以联苯、多聚甲醛为起始原料，氯化锌h2o为催化剂，在氯化氢的存在下经氯甲基化反应，得到了4 , 4 ' -二氯甲基联苯。
When a protein is desiccated in the presence of trehalose , water molecules bound to the protein structure by hydrogen bonding evaporate and the sites are then replaced by the sugar to maintain an intact confirmation ( 42 ? 45 ) 当蛋白在海藻糖存在下干燥，经氢键结合在蛋白结构上的水分子蒸发掉，留下的位点随后被糖替代，确保了结构的完整。
A polyaniline / polyisoprene composite film with permselectivity was synthesized by electrochemical method for the first time , which can determine selectively h2o2 in the presence of electroactive interferent ascorbic acid 采用电化学方法首次制备了具有特殊渗透选择性的聚苯胺/聚异戊二烯复合膜，它能在抗坏血酸存在下让过氧化氢选择透过。
Some coumarin derivatives are synthesized through pechmann reaction with catalytical amount of sulfuric acid . microwave irradiation is used and moderate to excellent results are got . the method is also very fast and convenient 在催化量硫酸的存在下，用微波辐射进行pechmann反应，制备香豆素衍生物，获得中等至良好的产率。本方法快速方便。
The specificity of an analytical method is ability to measure accurately and specifically the analyte in the presence of components that may be expected to be present in the same matrix , such as impurity , degradation products and excipients 专属性系指在其他成分（如杂质、降解产物、辅料等）可能存在下，采用的方法能准确测定出被测物的特性。
Well - ordered 3d - cubic , 2d - hexagonal , and disordered mesoporous silica films were synthesized by using non - ionic alkyl polyethylene oxide ( peo ) surfactants as a template , under the existence of different kinds acids respectively 摘要在不同种类酸的存在下，以非离子型烷基聚氧乙烯表面活性剂为模板分别制备出有序三维立方、二维六方和无序结构的介孔氧化硅薄膜。
Mixing experiments with ngf and c . chinensis extract revealed an additive effect on neuritogenesis when low dose of both agents were used . whereas saturating dose ngf were used , there was no distinct additive effect 在低剂量的ngf和菟丝子提取物存在条件下，菟丝子提取物能明显地增加ngf诱导的pc12细胞分化；但是，在高浓度的ngf存在下这种增强作用并不明显。
Poly butyl acrylate ( pba ) / mmt composites were prepared by emulsion polymerization . then , pvc / ( pba - mmt ) nanocomposites were prepared by suspension polymerization of vinyl chloride in the presence of pba / mmt composites 利用乳液聚合的方法制备了聚丙烯酸丁酯( pba )无机mmt复合胶乳，并在pba mmt复合胶乳存在下，采用悬浮聚合法制备了pvc ( pba - mmt )纳米复合材料。
The optimal cp potential shifted to negative direction in seamud containing active srb , - 1030 mv ( vs . saturated cu / cuso4 electrode , cse ) or lower potential was needed . accordingly , the cp current density was about 11 ma / m2 在srb存在下，最佳阴极保护电位移向更负的值， - 1030mv （相对铜/硫酸铜电极， cse ）甚至更低的电位是需要的。在- 1030mvcse保护电位下，保护电流密度约为11ma / m2 。
In the presence of these chemicals or of temperatures above 43 degrees celsius , the channel allows sodium and calcium ions to flood into the nociceptor , stimulating it to generate a signal that translates into the burning sensation induced by heat , inflammation or spicy food 在这些化学物质存在下，或是体温超过43 ，该离子通道就会让钠与钙离子涌入痛觉受器；由此生成的讯息，则由脑部判读成热、发炎或辛辣食物所引起的烧灼感。
