查询词典 methyl-glyoxal

From the results, the extraction was optimized by using microwave-assisted derivatization at 300 watt for 3 sec with methyl chloroformate/methanol derivatization reagent and sample solution in the ratio of 2:1, and then extraction 30 min.

实验结果显示，利用搅拌子吸附萃取法结合气相层析质谱术分析尿液中胺基酸，衍生化功率为300瓦，衍生化时间为3秒，水样与氯甲酸甲酯/甲醇衍生化试剂体积比为2：1时有最佳衍生化条件。

First, aniline reacts with methyl chloroformate in the presence of tri-n-butylamine; then the unseperated mixture then reacts with aniline to get final product. The first step was quick, and finished within 30 min of refluxing.

该反应分两步进行，即在三正丁胺存在下，苯胺与氯甲酸甲酯加热回流生成苯胺基甲酸甲酯，后者不经分离再与过量苯胺继续反应，生成目标产物。

There are two synthetic methods for the two carboxylates starting from pyrrole,(1) the carbonylation of pyrrole using trichloroacetyl chloride and then the esterification reaction in methanol, or 2-MPC can be directly synthesized from pyrrole and methyl chloroformate,(2) the insertation of CO2 to pyrrole for the corresponding 1-pyrrole carboxylic acid or 2-pyrrole carboxylic acid and then the esterification reaction in methanol.

两种吡咯甲酸甲酯的合成从吡咯为起始原料有两种方法：（1）使用酰氯将吡咯酰化，然后与甲醇完成酯化反应，或者吡咯与氯甲酸甲酯直接合成吡咯甲酸甲酯；（2）先将吡咯通过CO2插入反应得到1-吡咯甲酸或2-吡咯甲酸，然后与甲醇反应完成酯化。

Synthesis process of 2,6-dichloro-3-methylaniline was investigated 3-methylaniline was first N-acetylated with acetic anhydride,then treated with chlorosulphonic acid and ammonia yielding the 2-methyl-4--benzenesulfonic amide,which wasin turn deacetylated,chlorinated and hydrolyzed to the title compound.Hydrochloric acid was used instead of sodium hydroxide in deacetylation and sodium chlorate instead of hydrogen peroxide as oxidant in chlorination.

合成工艺2，6-二氯-3-甲基苯胺调查3-甲基首次N-乙酰与醋酸酐，然后与氯磺酸和氨产量 2-甲基-4--苯磺酰胺基，而擅转乙酰，氯化和水解的标题compound.hydrochloric酸代替氢氧化钠乙酰氯酸钠代替双氧水为氧化剂，加氯。

By blast in GenBank, clone Y1218 shared 72% homology with Chromobacterium violaceum, clone Y1814 shared 88% homology with Pseudomonas putida,clone Y0140, 80% with Bacillus sp., and clone Y1038, 71% with Pseudomonas fluorescens. Some clones had homology with the degreadation of aniline, methyl parathion microbial organisms.

有80%的同源性，Y1038克隆和荧光假单孢有71%的同源性，有部分克隆和一些具有降解苯胺、甲基对硫磷等有机物的微生物有同源性。

The free radical scavenging properties of six Aloe species are to be investigated in some modified chemical system. The antioxidant was purified by silica column and thin layer chromatography and analyzed by HPLC. A fraction was purified from A. brevifolia Mill showed the most effective scavenging activities on 〓 and ·OH (66. 01% and 38. 98% respectively). With the analysis of IR spectrum, UV spectrum and mass spectrum, the structure of FA was identifed as 8-C-D-glucopyranosyl-2- [2-hydroxy] propyl-5-methyl-7-hydroxychromone. Its scavenging activity on free radicals is higher than that of aloe-emodin. Its antioxidant activity may be due to the phenoxyl on glucosyl chromone which can be react with free radicals and form relatively stable free radicals.

本研究利用分别产生超氧阴离子自由基和羟自由基的化学模型体系研究比较了不同品种芦荟提取物的清除活性氧自由基的抗氧化作用，进一步利用硅胶柱结合薄层层析法和反相高压液相色谱法，从短叶芦荟叶子中首次分离了具有较强自由基清除能力（超氧阴离子自由基和羟自由基清除率分别为66.01％和38.98％）的成分FA，利用红外光谱、紫外光谱和质谱等仪器分析结果推断出该活性成分的分子结构为8-C-吡喃葡萄糖-2-[2-羟基]-丙基-5-甲基-7-羟基对氧萘酮，它的自由基清除能力高于芦荟大黄素，是一种天然抗氧化剂。

RESULTS: Sixteen compounds, ursolic acid (1), indole-3-carboxaldehyde (2), indole-3-carboxylic acid (3), p-coumaric acid (4), azelaic acid (5), N-trans-feruloyl tyramine (6), blumenol A (7), 2-hydroxy-3-methylanthraquinone (8), rubiadin l-methyl ether (9), rubiadin (10), quercetin (11), luteolin (12), chrysoeriol 6-C-β-boivinopyranosyl-7-O-β-glucopyranoside (13), alternanthin (14), stigmasta-5, 22-dien-3β-ol (15), and α-spinasterol (16) were obtained from the EtOAc extract of Alternanthera philoxeroides.

结果：得到并鉴定了16个化合物，分别为乌苏酸(1)、吲哚-3-甲醛(2)、吲哚-3-甲酸(3)、对-香豆酸(4)、壬二酸(5)、N-反式阿魏酰基酪胺(6)、布卢姆醇A(7)、2-羟基-3-甲基蒽醌(8)、甲基异茜草素-1-甲醚(9)、甲基异茜草素(10)、槲皮素(11)、木犀草素(12)、柯伊利素-6-C-β-波伊文糖基-7-O-β-吡喃葡萄糖苷(13)、莲子草素(14)、豆甾醇(15)和α-菠甾醇(16)。

Results: The 12 kinds of toxicants including methyl acetate, ethyl acetate, benzene, toluene, ethylbenzene, butyl acetate, p-dimethylbenzene, m-dimethylbenzene, o-dimethylbenzene, n-butanol, cinnamene and cyclohexanone were separated well. Good linear relationship sensitivity and reproducibility were obtained and detection limits (S/N=3) of them were 0.2 mg/l respectively. Conclusion: In this paper, a new method for simultaneous determination of 12 kinds of toxicants by using gas chromatography has been described.

结果：对乙酸甲酯、乙酸乙酯、苯、甲苯、乙酸丁酯、乙苯、对二甲苯、间二甲苯、邻二甲苯、正丁醇、苯乙烯、环己酮12种有毒物质的分离效果好，线性和重现性均较好，方法的检测限达到0.2 mg/L。

Cinnamyl alcohol and methyl salicylate at all four concentrations showed repelling effect against the males.

桂醇和水杨酸甲酯在所测试的浓度范围内对雄虫具有明显的驱避效果。

Synthesis technology of cinnamyl methyl fumarate containing α,β-unsaturated carbonyl group and its antimicrobial activity was studied.

以α，β-不饱和羰基结构为母体设计合成反丁烯二酸桂醇甲酯，并对反丁烯二酸桂醇甲酯的抗菌活性进行了研究。

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。