乙酰基

Using levulinic acid and phenol as raw materials, hydrochloric acid as catalyst and thioglycolic acid as assistant catalyst, the synthesis technology of diphenolic acid, a new polymer material substitution for biphenol A, was investigated.

研究了以苯酚和新型平台化合物乙酰丙酸为原料，采用盐酸为催化剂、巯基乙酸为助催化剂催化合成高分子材料单体双酚酸的合成工艺。

Universal indicator paper,special indicator paper,ammonium fluoride,ammonium hydrogen difluoride,nbenzyldimethylamine,disinfectant paper,nacetylphenylhydrazine,mcresol purple,bromocresol green,fluorescein,eosin Y,ninhydrin,phenedons,potassium phthalate,pamimobenzene sulphonic acid anhydrous.

广泛试纸，精密试纸，氟化铵，氟化氢铵，N苄基二甲胺，消毒试纸，N乙酰苯肼，间甲酚紫，溴甲酚绿，荧光素，曙红Y，水合茚三酮，菲尼酮S，苯甲酸氢钾，无水对氨基苯磺酸。

Result: Seven phenolic compounds were identified as rosmarinic acid(1),gallic acid(2),gentisic acid 5-O-(6′-O-galloyl)-β-D-glucopyranoside(3),caffeic acid(4),p-coumaric acid(5),ethyl caffeate(6) and acteoside(7),respectively.

结果：分离得到7种酚类化合物，经结构鉴定为：迷迭香酸(1)，没食子酸(2)，龙胆酸5-O-(6′-O-没食子酰基)-β-D-吡喃葡萄糖苷(3)，咖啡酸(4)，对香豆酸(5)，咖啡酸乙酯(6)和acteoside(7)。

N-Carbobenzoxy-L-homoserinelactone was prepared via N-alkylation reaction of L-methionine and iodoacetamide with benzyl chloroformate as amino protecting agent.

以L-蛋氨酸为原料，氯甲酸苄酯为氨基保护试剂，与碘乙酰胺(I2微量)内酯化反应，合成N-苄氧羰基-L-高丝氨酸内酯。

Two synthetic routes of Caffeine have been determined and investigated after the analyzing and trying for the literal synthetic methods. In one route, the target compound was prepared from chloroacetyl chloride through six steps, the total yield is 50.5 %. In another route, the target compound was obtained from cyanoacetic acid through six steps, the total yield is 45%.

对目前咖啡因工业生产工艺进行了研究，并分析了咖啡因工业生产中所存在的问题，本文提出两条可行的工业化合成路线：一条是以氯乙酰氯为起始原料，经过六步反应制得目标化合物，总收率50.5％；另一条是以氰基乙酸为起始原料经过六步反应制得目标化合物，总收率45％。

Objective: To investigate the arrest effect of diallyl disulfide in the cell cycle of human nasopharyngeal carcinoma CNE2 cell line and its molecular mechanism.

目的：在前期工作的检测上，进一步探讨二烯丙基二硫(diallyl disulfide， DADS)对人鼻咽癌CNE2细胞周期的阻滞作用，并研究组蛋白乙酰化状态及其调控p21WAF1蛋白表达改变的情况。

AIM: To investigate the effect of PD98059, a specific repressor of extracellular signal regulated kinase1/2 (ERK1/2), on the proliferation of the murine lymphocytes. METHODS: Lymphocytes were isolated from lymphoid nodes of BALB/c mouse. After stained with carboxy fluorescein diacetate, succinimidyl ester, the cells were stimulated with polyclonal activators, concanavalin and phorbol 12,13 dibutyrate plus ionomycin.

分离小鼠淋巴结细胞，藉羧基荧光素乙酰乙酸染色，用多克隆刺激剂刀豆A蛋白或者佛波醇酯加离子霉素刺激，以流式细胞术分析PD98059对淋巴细胞增殖的影响；利用碘化丙锭染色分析PD98059对细胞周期的影响。

It is a convenient and efficient method of preparation of diethyl N--L-glutamate.

利用上述方法可以方便高效地制备N-［4-苯甲酰基］-L-谷氨酸二乙酯。

In order to carry out the separation of the azeotropic mixture dipropyl ether + 1-propyl alcohol by extractive distillation, we are studied the influence on the phase equilibria behavior four different solvent: 1-pentanol [2], butyl propionate [3], N,Ndimethylformamide [4] and 2-ethoxyethanol.

为了用萃取性蒸馏法分离二丙醚和1－丙醇组成的共沸混合物，我们正在研究4种不同溶剂对相平衡行为的影响：1-戊醇[2]、丙酸丁酯[3]、N，N－二甲基甲酰胺[4]和2-乙氧基乙醇。

As can be seen in Fig. 5, dipropyl ether will be recovered in the distillate using 1-pentanol, N,N-dimethylformamide and 2-ethoxyethanol as entrainers and butyl propionate is the only entrainer studied that inverts the volatility of the azeotropic mixture.

从图 5可以看出，使用1-戊醇、N，N-二甲基甲酰胺和2-乙氧基乙醇作为共溶剂时二丙醚将在馏分中回收，丙酸丁酯是唯一与共沸混合物挥发性相反的共溶剂。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。