查询词典 dithionite

The transition metal catalysis reduction, hydride reagents reduction, sodium dithionite reduction and bioreduction ware discussed.

综述了近年来α，β-不饱和羰基化合物α，β-碳碳双键和碳氧双键的选择还原研究进展，讨论了过渡金属催化还原、氢化试剂还原、连三亚硫酸钠还原以及生物还原。

Resulting the extraction technology of artificial culturing biofilms, the hydroxylamine hydrochloride (NH2OH·HCl) was selected to extract manganese oxides, and sodium dithionite (Na2S2O4) was used to separate manganese oxides and iron oxides.

参考人工培养生物膜的萃取方法，分别用NH2OH·HCl和Na2S2O4为萃取剂选择性萃取生物膜上的锰氧化物和铁、锰氧化物。

By mixing fatty acyl chloride, fatty acid and hydroxyethyl sodium dithionite, reacting in a normal-pressure reaction apparatus in a heated manner, the product is produced.

本发明IgeponA系列阴离子表面活性剂用脂肪酰氯、脂肪酸和羟乙基磺酸钠混合，在常压反应器中进行反应，加热反应一定时间后得产品。

Resulting the extraction technology of artificial culturing biofilms, the hydroxylamine hydrochloride (NH_2OHHCl) was selected to extract manganese oxides, and sodium dithionite (Na_2S_2O_4) was used to separate manganese oxides and iron oxides.

用选定的最佳条件对不同时间和地点采集的生物膜进行萃取，发现对目的组分的萃取率可达70.8%~94.6%，而对非目的组分的影响很小(3.3%~11.0%)，满足萃取分离的要求。

The mechanism was supposed as follows: polyfluoroalkyl iodides were initiated by sodium dithionite to give R〓 which was added to one double bond of diallylacetic acid, after the sequential radical cyclization and nucleophilic substitution to form bicyclo-lactones.

这是因为：多氟烷基碘化物在连二亚硫酸钠的引发下，得到自由基R〓，后者加成到二烯丙基乙酸中的一个—C=C—双键上，然后在碱性介质中进行分子内亲核反应得到双环内酯类产物。

Aniline compounds containing heptafluoroisopropyl was synthesized through taking sodium dithionite as evocating agent, and introducing heptafluoroisopropyl by free radical electrophilic substitution on benzene ring.

以连二亚硫酸钠为引发剂，在苯环上通过自由基亲电取代反应引入七氟异丙基，合成了一系列含七氟异丙基的苯胺类衍生物，研究了各种条件对反应的速度和收率的影响。

Polyfluoroalkyl iodides could react with unsaturated olefin acids in the presence of sodium dithionite by radical addition to give adducts. It was found that these adducts could form polyfluoroalkyl substituted γ or δ-lactones due to intramolecular nucleophilic substitution in the alkali solution.

研究发现：多氟烷基碘化物在连二亚硫酸钠存在下与不饱和烯酸经自由基加成得到的产物，能在碱性条件下进行分子内亲核取代反应形成五元或六元环的含氟内酯类化合物。

Methods The cardiac myocytes model of myocardial ischemia reperfusion injury was induced with sodium dithionite (Na2S2O4). The primary cultured cardiac myocytes of SD neonatal rats were randomized into six groups: normal group, model control group, high-dose β-asarone (25 μg/mL), middle-dose β-asarone group (12.5 μg/mL), low-dose β-asarone group (6.25 μg/mL) and medium group.

采用连二亚硫酸钠(Na2S2O4)建立心肌细胞MIRI模型，将原代培养的SD大鼠乳鼠心肌细胞分6组：正常对照组、MIRI模型组、β-细辛醚高、中、低剂量组(25， 12.5， 6.25μg/mL)、基质组。

The changes of total reducing substances, oxalate extractable Fe, dithionite citrate bicarbonate extractable Fe and phosphorus adsorption in oxic and anoxic layers of two paddy soils during 6 week flooding were examined under laboratory conditions.

在实验室条件下对两种水稻土在为期 6周的淹水过程中，其氧化层和还原层土壤中还原物质总量、草酸盐可提取铁、连二亚硫酸钠-柠檬酸-碳酸氢钠可提取铁和磷吸附的变化进行了研究。

Optimum extraction conditions were selected by the condition experiments and the concentration of Cu, Pb, Zn in main components were also determined for revealing the distribution of the heavy metals in the suspended particulate matters. It was found that hydroxylamine hydrochloride (0.006 mol/L NH2OH·HCl+0.01 mol/L HNO3) can remove most of Mn oxides, and sodium dithionite 0.8 mol/L Na2S2O4

结果表明，0.006 mol/L NH2OH·HCl+0.01 mol/L HNO3萃取30 min可以单独萃取悬浮颗粒物中大部分的锰氧化物，0.8 mol/L Na2S2O4（pH=6.0）萃取40 min可以同时萃取铁、锰氧化物，而对非目的组分的影响较小；悬浮颗粒物对Cu、Pb、Zn重金属有明显的富集作用，其中Cu主要结合在悬浮颗粒物的有机质组分中，Pb主要富集在铁、锰氧化物中，锰氧化物和有机质对Zn的分布起主要的富集作用。

Shop assistant: Please check at the door.

店员：请您到门口柜台交费。

In the end, transportation of PAHs in the environmental matrix was preliminarily investigated and discussed according to PAHs data of soils and sediments from a certain region in Shanghai. The result indicated that there are two or more pathways on PAHs transportation in the environmental matrix.

最后，对上海特定地区内PAHs在环境介质中的迁移径途进行了分析讨论，结果表明上海市土壤和沉积物等环境介质中PAHs的迁移存在多种途径。