查询词典 ethyl

Flavone and pyrocatechol were chosento act as model compounds of different structure aspects of flavonoids and theirreactions with α-hydroxyl ethyl peroxyl radical were studied. The rate constants of thereactions of α-hydroxyl ethyl peroxyl radical with flavone and pyrocatechol weredetermined to be 〓 and 〓,respectively.

我们又选择了黄酮体和邻苯二酚作为黄酮类化合物的结构模型，用脉冲辐解的方法研究了它们与α-羟乙基过氧自由基的反应动力学，得到黄酮体和邻苯二酚与α-羟乙基过氧自由基的反应速率分别为〓和〓〓。

Results Eleven compounds were isolated and identified as:quercetin(1),kaempferol(2),quercitrin(3),protocatechuic acid(4),gallic acid(5),protocatechuic acid ethyl ester(6),ethyl gallate(7),vanillic acid(8),1,5,7-trihydroxyl-3methylan...

结果得到11个化合物，分别鉴定为：槲皮素(1)、山柰酚(2)、槲皮苷(3)、原儿茶酸(4)、没食子酸(5)、原儿茶酸乙酯(6)、没食子酸乙酯(7)、香草酸(8)、1，5，7-三羟基-3-甲基蒽醌(9)、琥珀酸(10)、5-羟甲基糠醛(11)。结论化合物6、7、9、11为首次从该属植物中分离得到。

And Cucumis sativus L. were tested by bioassay-guided separation. The extracts from P. tomentosa flower with ethanol were extracted with petroleum ether, ethyl acetate and n-butanol. The inhibition rate of the ethyl acetate extract to growth of the 3 kinds of plant radicel were 99.89%, 63.53% and 32.74% respectively at 0.5 mg/mL concentration, and that of petroleum ether were 76.30%, 56.17% and 23.36%.

绒叶泡桐Paulownia tomentosa花乙醇提取物依次用石油醚、乙酸乙酯、正丁醇和水萃取后进行活性测定，结果表明，石油醚萃取物在浓度为0.5mg/mL时，对反枝苋、生菜和黄瓜种子胚根生长的抑制率分别为76.30%、56.17%和23.36%；乙酸乙酯萃取物在浓度为0.5mg/mL时，对反枝苋、生菜和黄瓜种子胚根生长的抑制率分别为99.89%、63.53%和32.74%。

Ethyl dicyanopropionate was synthesized by one-step reaction with sodium cyanide, paraformaldehyde and ethyl cyanoacetate in solvent.

由氰化钠、多聚甲醛和氰乙酸乙酯在溶剂中反应，一步合成二氰基丙酸乙酯，收率达80.2%，含量90.8

To produce lead tetraethyl solely because, a short time before the outbreak of the war, the Americans had established plants for us ready for production and supplied us with all available experience. In this manner we did not need to perform the difficult work of development because we could start production right away on the basis of all the experience that the Americans had had for years.

Sutton所写的《WALL STREET AND THE RISE OF HITLER 》一书中的资料，在1938年，德国空军急需500吨四亿铅添加剂，美国杜邦公司经过认真考虑，认为这样的需求肯定是用于战争目的，最终这批四乙铅通过纽约Ethyl出口公司借给了德国的Ethyl G.m.b.H。，这比交易纳粹德国航空部以及法本公司董事Mueller-Cunradi安排的。

The extracting ability of several organic solvents such as ethyl acetate, butyl acetate, glycerol triacetate, iso-amy lacetate, and n-butanol, was compared, and it was found that ethyl acetate was a good kind of organic solvent.

比较了几种不同的有机溶剂：正丁醇、乙酸丁酯、乙酸乙酯、三乙酸甘油酯、乙酸异戊酯等的萃取能力，发现乙酸乙酯是一种理想的提取溶剂。

The results showed that there were 8 kinds of aliphatic, 5 kinds of esters, 2 kinds of aldehydes, 2 kinds of nitrogen sulfur heterocyclic rings and one kind of hydrocarbon, alcoholics, ketone, lactones respectively in the analyzed 21 kinds of aroma components, and the content of furfural,β-methyl valeric acid, palmitic acid, nicotine, neohytadiene were higher, next were acetyl ethyl propionate, caleric acid, phenyl ethyl acetate, hydroxylic diethyl succinate.

结果表明，在分析出的21种香气成分中，分别有脂肪酸类8种，酯类5种，醛类2种，氮硫杂环类2种，烃类、醇类、酮类、内酯类各l种，其中相对含量较高的物质成分是糠醛、β-甲基戊酸、十六碳酸、烟碱、新植二烯，其次是乙酰丙酸乙酯、异戊酸、苯乙酸乙酯、羟基丁二酸二乙酯等。

The condensation of 3-Ethoxyphthalide was also conducted with ethyl acetoacetate and ethyl cyanoacetate.

对3位延伸出一个和两个碳原子的胺类衍生物的质谱裂解规律进行了探讨。

Conclu sion: The ethyl acetate elution of ethyl acetate fraction extract of Alisma orientalis can significantly inhibit urinary calcium oxalate stone formation in rats and be the most effective constituent of Alisma orientalis .

泽泻醋酸乙酯浸膏的醋酸乙酯洗脱液能抑制实验性高草酸尿症大白鼠体内肾草酸钙晶体的形成，是泽泻抑制尿草酸钙结石形成的有效部位。

2 Condensation of ketones with ethyl cyanoacetate catalysed by ammonium acetate-acetic acid results ethyl alkylidene cL-cyanoacetate in 3 l?.-89% yield under ultrasound irradiation at 4l-450C within

在超声波作用下，以芳香醛和丙二酸为原料，以膨胀石墨作催化剂，合成多种肉桂酸，于41～43℃反应3.5-10小时，产率65-97％。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。