查询词典 methyl-glyoxal

The effect of different reaction conditions,such as catalyst concentration,molar ratio of reactants,reaction temperature,reaction time,on the coupling reaction of trioxane and methyl formate synthesizing methyl glycolate and methyl methoxy acetate using sulfuric acid as catalyst has been studied.Through the analysis for the yield of products and system pressure,and comparison with other different acidity catalysts,we considered that the activation of formaldehyde was the control step of reaction rate to the...

以硫酸为催化剂，研究了三聚甲醛与甲酸甲酯偶联合成乙醇酸甲酯和甲氧基乙酸甲酯的反应中，催化剂浓度、原料配比、反应温度、反应时间等条件对反应过程的影响，通过对产物收率和系统压力变化的分析，并结合与其它不同酸强度催化剂的对比，得到甲醛的活化是偶联反应的速率控制步骤，催化剂的酸强度决定其对甲醛的活化能力，是影响偶联反应的主要因素。

The research indicated that under the compound use of hydroquinone and methyl quinone or independent use of phenothiazines or nitrogen oxygen free radical made the polymerization retarder, opposite-methyl-phenylsulfon made the esterification catalyst, toluol made the backflow including water condition, the acid mellowly compared to when it was 1.15, the production rate of the synthesis methylacrylic acid polyethylene glycol single methyl ether (400) ester may achieve 98.9%, was extremely similar to the overseas product functional group structure.

研究表明，在氢醌、甲醌复合使用或者单独使用吩噻嗪、氮氧自由基哌啶酮作阻聚剂，对甲苯磺酸作酯化催化剂、甲苯作回流带水的条件下、酸醇比为1.5时，合成的甲基丙烯酸聚乙二醇单甲醚(400)酯产率可以达到98.9%，与国外产品官能团结构十分相似。

Has established the Avey rhzomorph through the field test remains the analysis method in the sea cabbage and the soil, and remained to it in the sea cabbage and the soil has carried on the determination, the sample with the methyl cyanide extraction, after extracting the revolving concentration nearly did, with the few methyl cyanides dissolves, passed through PRS the solid phase extract column to purify again, eluent air-dried after the nitrogen with the nitrogen methyl imidazole and the trifluoroacetic acid bitter wine grows, the derivative with the highly effective liquid chromatography analysis, used the external standard legal quantity.

通过田间试验建立了阿维菌素在甘蓝及土壤中的残留分析方法，并对其在甘蓝和土壤中的残留进行了测定，样品用乙腈提取，提取液旋转浓缩近干后用少量乙腈溶解，再经PRS固相萃取柱净化，洗脱液经氮气吹干后用氮甲基咪唑和三氟乙酸酐衍生，衍生物用高效液相色谱分析，采用外标法定量。

Goal compound synthesis namely: Take the vanillic acid as outset raw material, obtains 4- hydroxyl - 3- anisole methyl formate with the methyl alcohol reflux conditions, then after the etherification, the nitration, the return to original state, the ring closure response obtains 6- methoxy - 7- animal pen oxygen radical kui zuo lin - 4- alkone, then passes through the chlorination, the substitution aniline, to escape responses again and so on animal pen oxygen radical, etherification to obtain the goal compound; The goal compound and the diethylamine had the amine substitution reaction to obtain TM1, namely 4- benzene amino - 6- methoxy - 7- [2- hydroxyl - 3-(N, N- two ethyl aminos) third oxygen radical] kui zuo lin; Through zuo has the etherification with the Austria niter to respond obtains TM2, namely 4- benzene amino - 6- methoxy - 7- [2- hydroxyl - 3-(2- methyl - 5- nitryl imidazole) third oxygen radical] kui zuo lin.

目标化合物的合成即：以香草酸为起始原料，与甲醇回流条件下得到4-羟基-3-甲氧基苯甲酸甲酯，然后经过醚化、硝化、还原、环合反应得到6-甲氧基-7-苄氧基喹唑啉-4-酮，然后再经氯化、取代苯胺、脱苄氧基、醚化等反应得到目标化合物；目标化合物与二乙胺发生胺取代反应得到了TM1，即4-苯氨基-6-甲氧基-7-[2-羟基-3-丙氧基]喹唑啉；通过与奥硝唑发生醚化反应得到TM2，即4-苯氨基-6-甲氧基-7-[2-羟基-3-(2-甲基-5-硝基咪唑)丙氧基]喹唑啉。

Organic substances (diethylene glycol, glycol methyl ether and methyl ethyl ketone) were used as nonsolvent additives and N-methyl-2-pyrrolidone used as a solvent in membrane preparation. The effects of PPESK concentration, the type of additives and the NSA concentration in casting solution on the morphology and performance of the PPESK hollow fiber ultrafiltration membrane were systematically investigated.

以PPESK为膜材料，NMP为溶剂，水为凝胶剂，选用乙二醇甲醚、一缩二乙二醇和丁酮为非溶剂添加剂，系统研究了聚合物浓度、添加剂种类和含量对PPESK中空纤维超滤膜结构和性能的影响，制备了一系列具有不同孔径和通量的中空纤维超滤膜。

In Chapter 5,the pyrolysis of substituted six-membered ring model compound 4-methyl pyridine has been investigated.Instead of detail theoretical analysis of the reaction mechanism,the general results have been proposed from the products distribution and the combination of the pyrolysis investigation of its analogous pyridine.The major products are H_2,C_2H_2,C_4H_2,C_3H_3N and HCN,here HCN is not a primary initial product at low extent of decomposition.The mole fraction profiles of products have been obtained from the near threshold ionization.The pyrolysis of 4-methyl pyridine is initiated from the methyl abstraction and hydrogen abstraction procedures which are associated with the understanding of the soot formation and the NOX precursor correspondingly.

主要产物为H_2，C_2H_2，C_4H_2，C_3H_3N和HCN，其中HCN为非低温时的热解产物；通过近阈值电离并导出物种随温度变化的摩尔分数曲线，更详细地定量地描述了产物随温度的变化。4-甲基吡啶热解主要从母体脱甲基和脱氢两个初始反应出发，一种趋势是形成大质量数的苯并或杂环的多环化合物，有助于了解炭黑形成过程中的复杂化学过程；另一趋势是开环生成小的碳氢和腈类物质，实验得出的含氮物质的种类及随温度变化有助于了解NO_x的前驱物质的形成及其变化规律。

By research on the concentration change and distribution of methyl bromide in the container, we found that in the first period of fumigating, the absorption of the goods to methyl bromide became quickly, so did the concentration decline of the fumigant because of leakage of the carton itself. The distribution of the fumigant is not uniform in the aclinic and vertical directions. The absorption of the goods to methyl bromide completed after 6 hours delivered the gasified fumigant and the distribution of the concentration in space got balance.

对溴甲烷在集装箱内浓度的变化与分布规律进行研究，发现熏蒸开始阶段，货物对熏蒸剂的吸附及箱体渗漏使气体浓度下降较快，且在水平和垂直方向都存在分布不均匀的现象，气化投药后6小时，货物对溴甲烷的吸附已基本完成，浓度空间分布达到平衡。

These products are made by the transesterification of lauryl alcohol and methyl laurate, stearyl alcohol and methyl palmitate and stearyl alcohol and methyl behenate.

这些产品是通过十二醇和戊酮酸甲酯、硬脂醇和棕榈酸甲酯、硬脂醇和苯甲酸甲酯的脂交换反应得来。

On the basis of spectral analysis, these compounds were identified as Kaempferol , Kaempferol-3-O-β-D-glucopyranoside , Kaempferol-3-O-β-D-galactopyranoside, Quercetin , Quercetin-3-O-β-D-arabinopyranoside, Quercetin-3-O-β-D-galactopyranoside, gallic acid, methyl gallate-4-O-β-D- galactopyranoside, caffeicacid, methyl caffeate, 4-cafeoyl-(3"a, 4"a, 5"β)- trihydroxyquinic acid, 3"-cafeoyl-(3"a, 4"P, 5"P )-trihydroxyquinic acid methyl ester, 5"-cafeoyl-galactonic acid , pumiloside, loganic acid , 5R,6S,7E-megastima-3-on-7-en-9-ol 9-O-β-D-glucopyranoside. 2a, 3β-dihydroxy-oleanoic acid , 2a, 3β, 23-trihydroxy-oleanoic acid, 3a, 6a-dihydroxy-oleanoic acid, 3β-hydroxy-ursoic acid, 2a, 3a, 23-trihydroxy-ursoic acid , 2a, 3β, 23-trihydroxy-ursoic acid, 2β, 3β, 19a -trihydroxy-ursoic acid, 2a , 3β, 19a -trihydroxy-ursoic acid-28-O-β-D-glucopyranoside , 2a. 3a, 19a-trihydroxy-ursoic acid-28-O-β-D-glucopyranoside, 2a, 3a, 19a, 23-tetrahydroxy-ursoic acid, 1a, 3a, 19a, 23-tetrahydroxy-ursoic acid-28-O-β-D-glucopyranoside , 3a, 19a, 23-trihydroxy-ursoic acid.

从珙桐中分离鉴定得到了28种化合物，它们分别是：山奈酚，3-O-β-D-吡喃葡萄糖基-山奈酚甙，3-O-β-D-吡喃半乳糖基-山奈酚甙，槲皮素，3-O-β-D-吡喃阿拉伯糖基-槲皮素甙，3-O-β-D-吡喃半乳糖基-槲皮素甙，没食子酸，4-O-β-D-吡喃半乳糖基-没食子酸甲酯，咖啡酸，咖啡酸甲酯，4-咖啡酰基-(3&α，4&α，5&β)-三羟基鸡纳酸，4-咖啡酰基-(3&α，4&β，5&β)-三羟基鸡纳酸甲酯，5'-咖啡酰基-半乳糖酸，pumiloside，loganic acid，5R，6S，7E-megastima-3-on-7-en-9-ol9-O-β-D-glucopyranoside，2α，3β-二羟基齐墩果酸，2α，3β，23-三羟基齐墩果酸，3α，6α-二羟基齐墩果酸，3β-羟基熊果酸，2α，3α，23-三羟基熊果酸，2α，3β，23-三羟基熊果酸，2β，3β，19α-三羟基熊果酸，2β，3β，19α-三羟基熊果酸-28-O-β-D-吡喃葡萄糖甙，2α，3α，19α-三羟基熊果酸-28-O-β-D-吡喃葡萄糖基甙，2α，3α，19α，23-四羟基熊果酸，2α，3α，19α，23-四羟基熊果酸-28-O-β-D-吡喃葡萄糖基甙，3α，19α，23-三羟基熊果酸。

They were acetic acid, benzaldehyde, n caproic acid, methyl pentadecanoic methyl ester, glycerin, benzoic acid,,9 octadecadienoic methyl ester, squalane, stearic acid and oleic eicosyl ester.

它们是乙酸、苯甲醛、正葵酸、-甲基十五烷酸甲酯、丙三醇、苯甲酸、，9-十八碳二烯酸甲酯、角鲨烷、硬脂酸和二十烷基油酸酯。

Now, however, all children continue in "comprehensive" schools, and the eleven-plus determines which courses of study the child will follow.

然而现在，所有的孩子都要在综合学校继续学习，所以这次考试只是决定他们将要学习哪些课程。

Cultivatable land , and led to a general recognition that development must not be carried at the cost of agriculture .

城区的迅速扩大在很多情况下侵占了宝贵的可耕地，使人们普遍认识到发展不能以牺牲农业为代价。