查询词典 acid reaction

The method has high sensitivit,it is based on the nitrite catalysed discoloring reaction of indigo carmine by potassium bromate in phosphoric acid medium.

基于磷酸介质中NO－2催化溴酸钾氧化靛红的褪色反应，建立了测定痕量NO－2的新方法，并讨论了其动力学条件。

Under the optimal reaction conditions the acid value of the esterified production is the lowest,and the esterified degree is complete.

在最优条件下，鱼油的乙酯化产品酸值最低，乙酯化程度最高。

Methods: 2ethyl aniline was used as starting material of the synthesis and was processed by acetic anhydride acylation, strong nitric acid nitraction at low temperature, and desacyl synthesis to produce 2ethyl5nitro aniline. The product was then synthesized to 3methyl6nitro1Hindazole by using ringclosing reaction in the presence of NaNO2, and then ethylated to obtain 2,3diethyl6 nitro2Hindazole. The latter compound was then reduced by SnCl2/Hcl to get target compound 2,3diethyl6nitro2Hindazole.

以2乙基苯胺为原料经醋酐酰化、浓硝酸低温硝化及去酰基保护合成2乙基5硝基苯胺，后用亚硝酸钠关环得3甲基6硝基1H吲唑，经硫酸二甲酯甲基化得2，3二甲基6硝基2H吲唑，最后用氯化亚锡将其还原得到目标产物，通过1H NMR确定结构与目标产物一致。

Methods: 2-ethyl aniline was used as starting material of the synthesis and was processed by acetic anhydride acylation, strong nitric acid nitraction at low temperature, and desacyl synthesis to produce 2-ethyl-5-nitro aniline. The product was then synthesized to 3-methyl-6-nitro-lH-indazole by using ring-closing reaction in the presence of NaNO2, and then ethylated to obtain 2, 3-diethyl-6- nitro-2H-indazole. The latter compound was then reduced by SnC12/Hcl to get target compound 2, 3-diethyl-6-nitro-2H-indazole.

以2-乙基苯胺为原料经醋酐酰化、浓硝酸低温硝化及去酰基保护合成2-乙基－5-硝基苯胺，后用亚硝酸钠关环得3-甲基－6-硝基－1H-吲唑，经硫酸二甲酯甲基化得2，3-二甲基－6-硝基－2H-吲唑，最后用氯化亚锡将其还原得到目标产物，通过1HNMR确定结构与目标产物一致。

The research results showed that the time of illumining on the reaction system has strong effect on the production, and methane acid and formaldehyde are the prior products.

通过这一研究表明，光照时间对产物量有很大影响。

Compared with acid medium concentration and reaction time, temperature is the most notable factor to the leaching results.

在介质浓度、作用时间和温度影响淋滤结果诸因素中，温度的影响尤为明显。

The 3,4-dimethoxybenzene was nitrated by mixed acid of HNO3-H2SO4 under the reaction temperature of 0~5℃. 3,4-dimethoxynitroben-zene was obtained by filtration, and its yield reached over 97%.

在0~5℃低温条件下，以硝酸和硫酸按比例配成的混酸进行硝化，反应结束后过滤得到3，4-二甲氧基硝基苯，该步反应的收率有97%。

By the use of new nitrating agent, the reaction eliminated the use of concentrated sulfuric acid and was environmental friendly with high atom economy.

该方法通过改变硝化剂，不仅成功地避免了浓硫酸的使用，而且提高了原子经济性，具有良好的环境效益。

When starch was oxidized and acid-thinned at the same time, the reaction efficiency will be increased.

在制备过程中，酸解和氧化同时进行，可以缩短反应时间，提高反应效率。

Secondly, the two-layer porous silicon with different porosities was formed by the anodic reaction in hydrofluoric acid solution.

在这双层多孔硅上第一次利用超高真空CVD低温外延技术，生长了硅单晶外延层。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。