乙酰化值

This article introduces a simple method, which is acetylation method, to determinate the hydroxy content in petroleum oxidation products.

文章介绍了一种测定石油氧化物中羟值的简便方法——乙酰化法。

It is found that when the molar ratio of sulphoxide,pyridine and acetyl bromide is 1∶0.6∶0.4,the catalytic effect on the ring-enlargment is the best,and the yield and purity of the final product can reach 76% and 97% respectively at a pH of 1.8 in toluene under refluxing for about 3.5h.

通过正交实验可得出以下结论：当N，N′-双脲-亚砜为2.5∶1，乙酰溴-亚砜为0.4∶1，吡啶-乙酰溴为1.5∶1，回流时间为3.5h，酸化pH值为1.8时，扩环反应结果最好，总收率可达76%，纯度97%以上。

Then we compared cleavage rate and blastocyst rate among different groups. After that we evaluated the quality of blastocysts by using ICM/TE (Inner cell mass/Trophectoderm cells) ratio via staining with propidium iodide and Hoechest333258, and analyzed the level of genome methylation and histone acetylation by immunofluorescence.

比较各组受精卵的卵裂率和囊胚发育率；并应用碘化丙啶和Hoechest333258对囊胚进行染色，利用ICM/TE值评价各组胚胎体外发育的质量；同时将囊胚进行免疫荧光染色，观察其基因组甲基化和组蛋白乙酰化的水平。

acetyl chloride, a novel fluorescence derivatization reagent, has been developed for the determination of sterols and stanol .

采用荧光衍生化试剂2-(9-咔唑)乙酰氯，对天然产物谷甾醇、豆甾醇、菜油甾醇及谷甾烷醇的柱前衍生化条件，包括催化剂的种类、反应温度、衍生化时间等进行了考察，结果表明：催化剂选用三乙胺，反应温度80℃，时间20min，衍生产物具有恒定的最大检测响应值。

Three methods for the preparation of 1,2,4-trizolone~5 are provided. 22 compounds are prepared. 3, 4-disubstituted 1,2,4-trizolone-5 is prepared by reacting amide with ethyl hydrazine-fornate at 110癈 for 3h in the presence of phosphorus oxychloride, following neutralization and cyclization reaction, giving to 74.5 % yields,which is 30% more than the literature value.

以三氯氧磷为缩合剂，使酰胺和肼基甲酸乙酯在110℃反应3h，经碱中和、环化反应，合成3，4-二取代-1，2，4-三唑酮-5，两步反应总产率达74.5％，与文献报道值相比，高出了30％以上，在三唑酮类衍生物的合成方法中具有很大的突破性。

Then dendrimer-like polyamidoamine s based on the silica gel surface were prepared using Micheal addition of the amino and methyl acrylate,and ester-exchange of ethylene diamine and the ester group.

用硅烷偶联剂对硅胶表面进行氨基功能化，利用氨基与丙烯酸甲酯发生的Michael加成反应和乙二胺与酯进行的交换反应在硅胶表面合成了聚酰胺-胺树状大分子；利用红外光谱对PAMAM-SG的结构进行了表征，研究了溶液pH值、ρ(Ni2+)和温度对PAMAM-SG吸附Ni2+能力的影响。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。