查询词典 acid reaction

Under the optimized parameters,i.e.,resorcinol to potassium carbonate molar ratio of 1∶0.5,reaction temperature of 155℃-160℃,reaction time of 6 hours-7 hours,and dimethyl acetamide as solvent,the yield of 2,6-dihydroxybenzoic acid was up to 29.38%.

溶剂羧化法Kolbe-Schmitt反应，是在有机溶剂氛围中，由酚的成盐和酚盐的羧化两步完成，一直应用在农药、医药以及化肥的合成过程中。

Five of their single crystals were obtained and their structures were determined by X-ray diffraction. By comparison, it was found that dithiocabamate complexes often formed an exactly planar MS4 unit, such as [Mo(R2dtc)2]; and also formed a special MS 5 unit, such as [Cu2(R2dtc)4], the copper atom lies in a distorted square-pyramidal environment.Four kinds of heteropoly acids were prepared and characterized; a series of solid superacid catalyst of supported heteropoly acid were prepared and characterized; regioselectivites of chlorobenzene mononitration with nitric acid with different heteropoly acid on different supports and reaction conditions have been investigated.

培养并解析了5个该类配合物的单晶结构，通过比较，发现二硫代氨基甲酸盐与过渡金属容易形成四配位结构，金属原子与4个硫原子共平面，比如二乙基二硫代氨基甲酸钼；也能形成比较特殊的五配位结构，比如二乙基二硫代氨基甲酸双核铜，Cu原子与5个S原子相连，处于一个变形的四方锥结构的配位环境。

The results show high selectivity when the temperature is controlled at 50 CC , and the nitrated reaction time is 90 mm, toluene is nitrated by using 95% nitric acid as nitrating reagent at the presence of acetic anhydride, 1.0g silicotungstic acid catalyst is calcinated at 300℃ for 1.5h. The o/p (ratio of ortho to paro isomer of toluene nitration) ratio is 0.89 in product distribution of toluene nitration, lower than 1.67 using sulfonitric acid as catalyst. The yield of products is 91.6%.

结果表明，在醋酐存在条件下，以CCl4为溶剂，以质量分数为95%的硝酸为硝化剂，反应温度控制在50℃，反应60 min， 1.0g经300℃焙烧1.5h后的硅钨酸催化剂，对甲苯表现出强的区城选择性，甲苯硝化产物o/p值（甲苯硝化产物邻位和对位异构体的质量比）达0.89，较硝硫混酸的1.67显著降低，产物收率达到91.6%。

Butyl p-hydroxybenzoate was synthesized from p-hydroxybenzoic acid and butanol with sulfoacid resin as catalyst. The optimum conditions were as follow: ratio of n-butanol, p-hydroxybenzoic acid and sulfonic acid resin was 0.25 mol ∶ 0.05 mol ∶ 1.5 g, refluxing for 5 h using water separator at the reflow reaction temperature.

摘 要：以对羟基苯甲酸和丁醇为原料，用磺酸树脂作催化剂，催化合成了尼泊金丁酯，优化反应条件为：n∶ n=5 ∶ 1，催化剂磺酸树脂的用量为对羟基苯甲酸质量的21%，反应温度为回流温度，反应时间为5 h。

Thiobarbituric acid was synthesized by sulfourea and diethyl malonate in sodium alcohol and 5-Arylidene thiobarbituric acid was prepared by the Knoevenagel condensation reaction from benzaldehyde and thiobarbituric acid.

采用丙二酸二乙酯和硫脲在乙醇钠存在下合成了硫代巴比妥酸，再分别采用固相反应和水相反应，由硫代巴比妥酸和苯甲醛经Knoevenagel缩合反应，制备了5-亚苄基硫代巴比妥酸。

Based on the experimental evidence, Usnic acid soluble in chloroform and acetone, and Usnic acid with KOH react show yellow in Lichens＇s color reaction; Usnic acid add the mixture of KOH and NaCl react show dark-yellow.

据实验证明，松萝酸易溶于氯仿及丙酮，且在地衣显色反应中，松萝酸与KOH反应显黄色；与KOH和NaCl混合液反应显深黄色。

In the second chapter, p-hydrazino-benzenesulfonic acid was prepared by diazotizing sulfanili acid with sodium nitrite. The diazanium salt was then reduced with sodium hydrogen sulfite and acidified with sulfuric acid to give 83.4% product. After several repeated experiments, the reactant and reaction condition are determined.

由于Cy系列试剂的特殊结构使其在荧光标记方面与其他试剂相比有着显著的优点，在生物芯片和蛋白质组学方面得到了广泛的应用，因此文章综述了Cy系列试剂在DNA芯片和蛋白质组学研究中的标记方式以及应用。

The results of acid wash with different acid concentration, reaction time and acid temperature were discussed.

主要考查了酸溶液的浓度、反应时间及酸溶液的温度等因素对灰份去除结果的影响。

The result indicated that MgO and α- methacrylic acid can together thicken epoxy, and the speed of thickening epoxy become quickly with the increasing content of MgO; when the ratio of MgO and α- methacrylic acid is 3:1, thickening epoxy have a better effect; the thickening mechanism: the terminal corboxyl group of α- methacrylic acid react with MgO, and it accompany with large numbers of heat, the heat can accelerate the reaction between the terminal corboxyl group with the secondary hydroxyl groups of epoxy, intermolecular hydrogen bonding which the water of above-mentioned formation result in and complex compound which format the metal atoms and carbonyl group complexing collective increase the viscosity of epoxy resin.

结果表明：MgO和α－甲基丙烯酸配合可增稠环氧树脂，随着MgO加入量的增加，环氧树脂增稠的速度加快；MgO与α－甲基丙烯酸为3：1时，增稠环氧树脂的效果较好；推测环氧树脂的增稠机理是α－甲基丙烯酸中的端羧基与氧化镁反应，放出热量促使其端羧基与环氧树脂中的仲羟基反应，上述反应生成水产生的氢键和羰基与氧化镁中的金属原子形成络合物共同导致环氧树脂的粘度增加。

AIM: To analyze the changes of the total bile acid and the ratio of cholic acid/chenodeoxycholic acid in serum of patients when rejection reaction and the transplanted liver functional recovery delay happen after liver transplantation.

目的：评价肝移植术后患者血清总胆汁酸水平、胆酸，鹅脱氧胆酸比值在肝移植术后发生排斥反应及肝功能延迟恢复时的变化规律。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。