查询词典 in the presence of

In the fourth chapter, 5-phenyl-1,2,4-triazine(3) was synthesized from(5-phenyl-1,2,4-trizin-3-yl)hydrazine in the presence of sodium ethoxide firstly. Themerit of this process was simplification of operation and good yield (more than 90%),which to our knowledge has not been reported so far in literature.

第四章首先以(5-苯基-1，2，4-三嗪-3-基)肼为原料，在乙醇钠作用下经一步反应，合成了化合物5-苯基-1，2，4-三嗪(3)；该法操作简单，产率高(＞90％)，迄今未见文献报道。

Analogous complexes 3a" and 4a"= CpRu(PPh32, Ar = para-C6H4OMe containing methoxy group at the para-position of gem-diphenyl group were similarly obtained from protonation of the corresponding acetylide complexes via formation of vinylidene intermediate. But only complex 3a'= CpRu(PPh32, Ar2 = fluorenyl is stable in solution, and decomposed to unidentified complex when heated to reflux in THF. Deprotonation of complex 4a in the presence of base gives neutral acetylide complex 6a.

在两个相邻位置的苯基对位位置上接有一甲氧基的衍生物3a&和4a&也可利用类似的质子化反应合成，唯有错合物3a'= CpRu(PPh32， Ar2 = fluorenyl 可以稳定於溶液中，不会进行上述反应，如将其溶於四氢呋喃溶液加热至沸腾则会分解产生无法鉴定的化合物。

The formyl-2.2-bisferrocenyl-propane was synthesized by formylation reaction of 2.2-bisferrocenyl-propane with DMF in the presence of POCl3 in CHCl3 at (55±2)℃ in high yield and conversion, the diformyl-bisferrocenyl-propane was also obtained simultaneously in low yield.

随着二茂铁化学基础理论的发展及二茂铁衍生物的大量合成，人们也逐步发现了它们在许多领域的应用前景[1]，尤其是作为燃速催化剂，具有比金属氧化物更高的燃速催化效果。

The formyl-2.2-bisferrocenyl-propane was synthesized by formylation reaction of 2.2-bisferrocenyl-propane with DMF in the presence of POCl3 in CHCl3 at (55±2)℃ in high yield and conversion, the diformyl-bisferrocenyl-propane was also obtained simultaneously in low yield.

随著二茂铁化学基础理论的发展及二茂铁衍生物的大量合成，人们也逐步发现了它们在许多领域的应用前景[1]，尤其是作为燃速催化剂，具有比金属氧化物更高的燃速催化效果。

Furoin was synthesized from furol with VB1 as the catalyst,which was then reacted with acetyl chloride, lauroyl chloride ,benzoyl chloride,α-furoyl chloride and 3-α-furyl acryloyl chloride,respectively;corresponding monoester compounds of furoin were synthesized in THF in the presence of sodium hydroxide under reflux.

以糠醛为基础原料，经维生素B1催化合成糠偶姻，再由糠偶姻分别和乙酰氯、月桂酰氯、苯甲酰氯、α-呋喃甲酰氯和3-α-呋喃烯丙酰氯反应，在NaOH/无水THF体系中，于水浴回流条件下合成了相对应的糠偶姻单酯类化合物。

Using cytochalasin D to prevent global actin from forming filamentous structures, the production of Heliothis armigera nuclear polyhedrosis virus in Hz-AM1 cells grown in the medium containing 0.5μg/ml CD was completely inhibited while its production was reduced to 10〓 in the presence of 0.1μg/ml CD by plaque assay. However, Western blotting revealed that the actin quantity in infected host cells treated or untreated with CD was almost identical. Additionally, CD had no effect on the DNA synthesis of HaNPV.

Western blot表明细胞松弛素D并不影响受染细胞中肌动蛋白的含量，Dot blot表明病毒DNA的合成也没有受到影响，但电子显微镜超薄切片发现在0.5ug／mL细胞松弛素D中形成的病毒粒子形态与正常的有明显区别，认为细胞松弛素D抑制棉铃虫核型多角体病毒的增殖是因为抑制病毒的DNA和蛋白组装成完整有感染性的病毒粒子，即丝状肌动蛋白对病毒粒子的脱壳和DNA的复制、转录没有影响，但对病毒粒子的组装是必须的。

The silica/Polystyrene monocore-shell nanocomposite particles(95nm in diameter) were synthesized through miniemulsion polymerization by using sodium dodecyl sulfate surfactant,hexadecane costabilizer in the presence of silica particles(50nm in diameter) coated with methacryloxytrimethoxysilane.

采用细乳液聚合法，以3-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)表面改性的直径50nm的氧化硅粒子为核，在乳化剂、助乳化剂、引发剂存在的情况下制备了小粒径、单核核壳结构氧化硅/聚苯乙烯纳米复合微球。

Process for the preparation of phosphatidylserine of formula wherein R and R independently represent a saturated, mono-unsaturated or polyunsaturated acyl C10-C30, X=OH or OM where M=alkaline or alkaline earth metal, ammonium, alkylammonium including the transphosphatidylation reaction between phosphatidylcholine of the general formula wherein R and R and X have the above specified meanings, R=CH2-CH2- NH2 o CH2-CH2-N(CH3)3 and Serine in D, L or racemic form catalysed by the phospholipase D enzyme, characterised in that said reaction is carried out in a hydroalcoholic medium containing an aliphatic alcohol and in the presence of bivalent metal oxide.

本发明涉及制备式CH 2 OR 1 CHOR 2 CH 2 O-P-OCH 2 -CH(NH 2 )-COOHX的磷脂酰丝氨酸的方法，其中R 1 和R 2 独立地表示饱和的、单不饱和的和/或多不饱和的酰基C 10 -C 30 ，X＝OH或OM，其中M＝碱或碱土金属、铵、烷基铵，该方法包括通式CH 2 OR 1 CHOR 2 CH 2 O-P-OR 3 X的磷脂酰胆碱其中R 1 和R 2 以及X具有上述特别的含义，R 3 ＝CH 2 -CH 2 -NH 2 或CH 2 -CH 2 -N (CH 3 3 与D、L或外消旋形式的丝氨酸之间的转磷脂酰化反应，该反应是通过磷脂酶D酶催化的，其特征在于所述的反应是在包含脂族醇的含水醇介质中并且在二价金属氧化物的存在下进行的。

Chapter 6: Iodobenzene diacetate-mediated reactions of methylenecyclopropanes, vinylidenecyclopropanes and a methylenecyclobutane with phthalhydrazine give the corresponding [3+2] cycloaddition products in good yields under mild conditions. In these reactions, phthalhydrazine was transformed to a 1,3-dipole intermediate in the presence of iodobenzene diacetate. A plausible reaction mechanism has been proposed.

本论文对亚甲基环丙烷类化合物的一些化学反应性能进行了研究，发现了亚甲基环丙烷类化合物在不同试剂或不同催化剂作用下的一些新的化学转化并合成了一些结构简单但具有潜在应用价值的有机小分子。

In this work, isobutyl isobutyrate was prepared by the condensation of two molecular isobutyraldehyde in the presence of aluminium isobutoxide catalyst system.

依据间歇反应所得一系列数据，确定了异丁醛连续缩合反应工艺流程；考察了以异丁醛为原料，在 5～10℃，停留时间 1 5～ 2h ，在异丁氧基铝催化体系作用下，两分子异丁醛缩合成一分子异丁酸异丁酯；脱除催化剂后，粗产品精制得到纯度≥ 99 5 %的异丁酸异丁酯，异丁醛的转化率≥ 98 5 %，异丁酸异丁酯的选择性≥95 %。

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