乙酰乙酸酯

Their specific surface area and acid strength were measured, and their catalyt and SBA-15 were ic performance was evaluated in the synthesis of fructone by acetalization of ethyl acetoacetate with ethylene glycol.

用浸渍法制备了一系列负载型磷钨酸及其铯盐催化剂，载体包括超稳Y沸石、脱铝超稳Y沸石、SiO2和SBA-15，测定了催化剂的比表面积和酸强度，并在乙酰乙酸乙酯与乙二醇液相缩合制取苹果酯反应中考察了催化剂的性能。

The synthesis of fructone from ethyl acetoacetate and ethylene glycol using sulfonated activated carbon as solid acid catalyst was investigated.

以活性炭磺化制得新型固体磺酸磺化炭为催化剂，对乙酰乙酸乙酯和乙二醇合成苹果酯的催化工艺进行了系统研究。

Various reaction parameters such as ratio of ethyl acetoacetate to ethylene glycol,catalyst amount,reaction time and water-carrying reagent amount were studied.

讨论了酯醇比、催化剂用量、反应时间、带水剂用量对酯化率的影响。最佳反应条件为：n：n=1：1.8，催化剂用量为乙酰乙酸乙酯质量的2%，带水剂用量为20mL，反应时间3h。

_6P_2W_(17)VO_(62) catalyst was prepared and characterized by FTIR,and synthesis of fraistone over as-synthesized catalyst from ethyl acetoacetate and 1,2-propylene glycol was investigated.

制备了Dawson型磷钨钒酸铵催化剂，用FT-IR分析方法对催化剂进行了结构表征，并以乙酰乙酸乙酯与1，2-丙二醇为原料催化合成了苹果酯-B。

Supported 12-Phosphotungstic Acid and Its Salts as Catalysts for the Synthesis of Fructone and Fructone-B;2. Their catalytic activities were measured by synthesis of fructone-B from ethyl acetoacetate and 1,2-propanediol.

制备了一系列以脱铝超稳Y沸石为载体的磷钨酸及其铯盐催化剂，考察了催化剂在以乙酰乙酸乙酯和1，2-丙二醇为原料催化合成草莓酯反应过程中的性能。

Methods: A model to evaluate lymphocyte proliferation stimulated with a polyclonal activator, concanavalin A, was established by vital dye carboxyl fluorescin diacetate succinmidyl ester labeling technique. Effects of the different doses of anisomycin on the lymphocyte proliferation were estimated by flow cytometry and MTT methods. The propidium iodide labeling technique was applied to assay the effect of the different doses of anisomycin on changes of the lymphocyte cell-cycle stimulated by ConA or by phorbol ester plus Ionomycin. The percentage of the expression level of CD69 and CD25 on the activated lymphocytes was evaluated by fluorescin-conjugated monoclonal antibody double labeling technique.

以活体染料羧基荧光素乙酰乙酸琥珀酰亚胺酯染色，建立在多克隆刺激剂刀豆蛋白A刺激下评价小鼠淋巴细胞增殖的模型，通过流式细胞术和MTT法分析茴香霉素在不同剂量下对淋巴细胞增殖的作用；采用碘化丙锭染色分析茴香霉素对ConA或佛波醇酯加离子霉素刺激的小鼠淋巴细胞周期变化的作用；利用荧光标记的单克隆抗体双染技术和流式细胞术观察茴香霉素对小鼠CD3~+T细胞早期及中期活化标志分子CD69和CD25表达的影响。

This thesis consists of four chapters:Chapter 1: Michael addition of chalcones with active methylene compounds such as diethyl malonate, ethyl acetoacetate and nitromethane catalyzed by potassium hydroxide in anhydrous ethanol results Michael adducts in 72-98% yield under ultrasound irradiation in 25-150min.

第一章：研究了超声辐射下，氢氧化钾催化的查耳酮与活泼亚甲基化合物如丙二酸二乙酯、乙酰乙酸乙酯和硝基甲烷的迈克尔反应。

Optically active ethyl-3-hydroxybutyrate,a useful chiral synthon,was prepared by stereoselective reduction of ethyl acetoacetate of the bread yeast in organic solvent.

利用面包酵母在非水相中不对称还原乙酰乙酸乙酯，制备了光学活性的手性化合物S-3-羟基丁酸乙酯。

Could keep above 95% in the fixed beds. In order to achieve high stereo-selectivity with yeast, ethyl acetoacetate was used as the model substrate,and a novel approach was proposed to selectively inhibit R-enzymes in yeast before reaction.

以乙酰乙酸乙酯为模型底物，以丙烯酸、乙醚、二甲基亚砜、丙烯酰胺、正己烷等有机溶剂选择性地抑制酵母中R型酶，提高反应立体选择性。

The asymmetric reduction of prochiral P-oxo ester, aromatic ketone and aliphatic ketone to its corresponding chiral alcohol by yeast cells were studied respectively in this work when ethyl 4-chloro-3-oxobutyrate, acetophenone and 2-octanone were as the model substrates.

本文以4-氯乙酰乙酸乙酯、苯乙酮和2-辛酮分别为β-羰基酯、芳香酮和脂肪酮的模型底物，研究了利用活性酵母细胞催化这三类前手性酮不对称还原合成相应手性醇的反应特性。

The objective is to subjugate and discourage the people, because that allows the elite to continue to rule unopposed.

其目的是压制和打击人民的积极性，因为这可以让实权派继续统治不会沦为反对派。

GOD,this is the second time you vanquished me!

天啊，这是第二次你打败了我！