氯甲烷

Based on the characteristic that boracic acid (H3BO3) has a condasation and complexation reaction with 3-MCPD forming a negative-charged adduct in aqueous phase, arapid method for the direct determination of 3-MCPD in HVP by capillary electrophoresis with conductivity detection was investigated.

利用硼酸能与3-氯-1，2-丙二醇(3-MCPD)上的2个邻位羟基进行键合生成配合阴离子、从而增加多羟基化合物的负电荷的特性，在15 mmol/L 三羟甲基氨基甲烷-10 mmol/L H3BO3(pH 8.3)介质中，采用毛细管电泳/电导检测法分离检测了3-MCPD，该方法的线性范围为0.5-20 mg/L，检出限为0.1 mg/L(S/N=3)。

For a while chlorofluorocarbon gas, as used in spray cans and refrigerators, was believed to have an effect on the ozone layer in the upper atmosphere.

曾经一度认为，用于喷雾罐以及电冰箱当中的氯氟甲烷气体会对臭氧层产生影响。

Greenhouse gas - GHG Gas that helps cause the greenhouse effect. Includes carbon dioxide, methane and chlorofluorocarbons.

温室气体造成温室效应的气体，包括二氧化碳、甲烷和氟氯烃。

Includes carbon dioxide, methane and chlorofluorocarbons.

造成温室效应的气体，包括二氧化碳、甲烷和氟氯烃。

The alkali cellulose is then treated with chloromethane and propylene oxide to produce methylhydroxypropyl ethers of cellulose.

碱性纤维素然后被氯代甲烷和丙烯氧化物处理生产出甲基羟丙基纤维素。

Biogas methane can also be used to make methanol, an organic solvent and an important chemical for producing formaldehyde, chloromethane, organic glass, and compound fibre.

沼气甲烷还可以用来制作甲醇，一种有机溶剂，是生产甲醛、甲基氯、有机玻璃和合成纤维的重要化学物质。

Herein, we report the enantioselective total syntheses of slagenins A-C and their antipodes. Starting from readily available ethyl -4-chloro-3-hydroxy-butanonate, elongation of the carbon chain with diazomethane, followed by oxidation of the given α-diazoketone using distilled DMD, afforded a key intermediate α-ketoaldehyde .

本文从方便易得的-4-氯-3-羟基-丁酸乙酯出发，经重氮甲烷延伸碳连、DMD氧化相应的α-重氮酮，制得α-酮醛；该化合物与尿素在氢氟酸作用下，以协同方式非对映选择性的直接构建了cis-四氢呋喃并[2，3-d]咪唑啉-2-酮双环结构，进而合成了天然产物slagenins A、B、和C的对映体。

The auxiliary can be recovered in high yield (81%) only by filtering and recrystallization. Besides, some other aldehydes have been chosen to test the enantioselectivity of N,N\'-dibenzyl tartamide, in comparison with two other allylaborates reagents developed previously by Roush and Brown, respectively. The results show that %e.e. of homoallylic alcohol is superior to that of the former, and approaches the Brown reagent.

产物经S_N2反应得瑞格列萘中间体-甲基烯丙基-2-氯苯基-叠氮甲烷(17)；同时，将筛选出的新型手性配体N-苄基酒石酸二酰胺用于其他几种醛(正丁醛，异戊醛和环己醛)的不对称烯丙基化反应，并与广泛应用的Roush配体(22)和Brown配体(27)相比较，发现其立体选择性优于Roush配体，并接近Brown配体，但明显具有可回收利用的优势。

Effect of several reaction factors on the yield of the synthesis of methane sulfonyl chloride is discussed.

阐述了利用二甲基二硫在相转移催化剂作用下，于盐酸介质中经氯气直接氧化，一步合成甲烷磺酰氯的工艺过程，讨论了几个主要反应因素对产物收率的影响，确定了适宜的工艺条件。

On the above mentioned basis, the process method of preparing continuously methane sulfonyl chloride was suggested.

用合成反应经产品分离后的母液作反应介质，合成了甲烷磺酰氯产品，提高了反应收率，增加了经济效益，减小了环境污染，获得了综合利用的效果。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。