查询词典 in the presence of

In chapter 2, the Michael additions of functionalized organozinc iodides with α,β-unsaturated aldhydes, ketenones, esters and l-aryl-2-nitroetheneshave been investigated in the presence of Cu〓/ 2LiCl.

第二章主要研究了在低毒、稳定、易得、价廉的Cu〓存在下，带官能团的有机碘化锌与α，β-不饱和醛、酮、酯及1-硝基-2-芳基乙烯的Michael加成反应，并探讨了反应机理。

In addition,the activity of the putadiene polymerization catalyzed by SAAC.Nd.Fe-AlEt Cl-Al in the presence of phenanthroline and the relationship bet-ween the polybutadiene microstructure obtained with the content of Fe in SAAC.Nd.Fe were studied.

此外，初步考察了在邻啡绕啉存在下SAAC·Nd·Fe体系聚合丁二烯的活性以及所得产物的微观结构与络合物SAAC·Nd·Fe中Fe的含量关系。

By the polycondensation of amino acid 5-fluorouracil -1, 3-dipropyl esters with bis (2-chloroethyl) phos- phoramidic dichloride in the presence of 〓 or in vacuo, ten new polymers containing 5- fluorouracil, nitrogen mustard and amino acid were synthesized.

将1，3-双-5-氟尿嘧啶与二氯膦甲酸乙酯或二氯膦乙酸乙酯在DMF中反应制备得到20个三元共聚物，体外抗肿瘤试验表明：含有甘氨酸、缬氨酸、苯丙氨酸和酪氨酸的聚合加显示了一定的选择性，并且分析讨论了生物活性与结构之间的关系。

Now, a convenient, efficient pinacol coupling of aldehydes mediated by zinc in good yields has been carried out in ammonia water in the presence of a little crown ether. Adding a small amount of crown ether was highly effective to enhance the yields of pinacol from 63% to 84%.

本文报道一种简便、有效的水相呐偶合反应，它是在含有少量冠醚的稀氨水溶液中，使用锌粉促进醛基化合物进行水相呐偶合反应，其中加入少量的冠醚有助于提高反应的产率，呐醇产率由63%提高到84%。

Jerusalem was then as now a polyglottal region and could easily have produced one hundred and twenty persons who, in the presence of a cosmopolitan assemblage, might express themselves in fifteen different tongues.

耶路撒冷当时由於现在polyglottal地区，可以很容易产生120的人，在场的一个国际性组合，可能会表达自己，在十五个不同的舌头。

Jerusalem was then as now a polyglottal region and could easily have produced one hundred and twenty persons who, in the presence of a cosmopolitan assemblage, might express themselves in fifteen different tongues.

耶路撒冷当时由于现在polyglottal地区，可以很容易产生120的人，在场的一个国际性组合，可能会表达自己，在十五个不同的舌头。

METHODS Chlorodehydromethyltestosterone was synthesized from methyltestosterone by cycloxidization with hydrogen peroxide to obtain cycloproxene methyltestosterone, which subjected to chloridization with was hydrochloric acid in the presence of propanone to obtain chloromethyltestosterone, and then was subjected to dehydrogenation with DDQ using PTS as dehydrogenation catalyst in benzene.

以甲睾酮和H2O2环氧化反应得到环氧甲睾酮，再与盐酸在丙酮溶媒中进行氯化反应，得到氯甲睾酮，最后用2，3-二氯－5，6-二氰基对苯醌在PTS催化下脱氢得到脱氢氯甲睾酮。

In the presence of SnCl2- C6H5Me3NBr and microwave irradiation, the mixture of tin-indium and propargyl bromide reacted quickly with aldehydes in aqueous media to produce the homopropargyl alcohols exclusively in high yields.

在SnCl2 和C6H5Me3NBr存在及微波照射下，锡-铟和炔丙基溴的混合物在水介质中与醛快速反应，生成高产率的单一的高炔丙醇。

RESULTS: HE stained cells were fusiform-shaped with pseudopodia, round or oval nucleus. The cytoplasm was blue after stained with the toluidine blue. The immunohistochemical test revealed that there existed positive expression of type Ⅰ collagen in the cells. In the presence of 10% calf serum, IGF-Ⅰ significantly improved cell proliferative activity in a dose-dependent manner within effective dose range.

结果：苏木精－伊红染色细胞多为梭形，有伪足伸出，细胞核为圆形或椭圆形；甲苯胺蓝染色，胞浆为深蓝色；免疫细胞学方法检测表明纤维环细胞有Ⅰ型胶原表达；在体积分数为0.1的血清条件下，胰岛素样生长因子Ⅰ能提高细胞的增殖活性，并且在有效浓度范围内呈剂量效应关系。

A general method for preparing multi-cyclic indolizine compounds(1a—1c, 2a—2b and 3) in moderate yields(45%—71%) by a 1,3-dipolar cycloaddition reaction of pyridinium N-ylides, isoquinolinium N-ylides or quinolinium N-ylides to 1,4,4a ,8a-tetrahydro-1,4-methanonaphthalene-5,8-dione, followed by an aromatization, in the presence of tetrakispyridine cobalt dichromate is described.

在 [ 4Co( HCr O4 ) 2 ]存在下，吡啶叶立德、喹啉叶立德或异喹啉叶立德分别和 1 ，4，4a，8a-四氢-1 ，4-桥亚甲基萘-5 ，8-二酮反应，一步法合成了中氮茚类多环化合物( 1 a～ 1 c，2 a～ 2 b，3 )。该方法原料易得，反应条件容易控制，为合成这类化合物提供了新方

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷