酸性

β-Methylhydrogen itaconate was prepared from itaconic acid and methyl alcohol with benzoyl chloride as catalyst.

摘 要：以衣康酸和无水甲醇为原料，酸性催化下酯化合成β-衣康酸单甲酯。

Another example is methyl orange, which is red in acids and yellow in alkali solutions.

另一个例子是甲基橙，它在酸性溶液中为红色而在碱性溶液中为黄色。

The possibility of preparation of methylal from methanol and formaldehyde through slurry catalytic distillation catalyzed by acidic cation exchange resin with large size pores is discussed.

研究了以甲醇和甲醛为原料，以大孔径强酸性阳离子交换树脂为催化剂，通过浆料催化精馏工艺制备甲缩醛的可行性。

The electro-catalytic properties and chemical stability of the Pt/WC powder microelectrode for t...

采用循环伏安和线性扫描等方法研究了酸性介质中Pt/WC粉末微电极对电化学析氢过程的电催化行为。

The different performance between HZSM-5 catalyst and HL catalyst is mainly due to the different acidity, specific surface and micropore volume which they have.

这种反应性能的差异主要是由于HZSM-5沸石和HL沸石的酸性特征、表面积和微孔体积不同所造成的。

Efficacy: This product contains shark essence, collagen protein, elastin, hyaluronic acid, compound amino acid and other ingredients, which can accelerate macromolecule ingredients to generate, complement necessary elasticity and moistness to eye skin, prevent fine wrinkles caused by dryness and keep skin firm. It is fragrance-free, pigment-free, weak acidic and mild, and can make eye skin stretchy and smooth.

功能：本品采用鲨鱼精华、胶原蛋白、弹性蛋白、透明质酸、复合氨基酸等主要成份；能抑制高分子成份减少，同时促进高分子成份生成，充分补充眼部所需的弹性和水润，防止因干燥而引起的小细纹，保持肌肤的紧致张力，无香料、无色素、呈弱酸性，温和零刺激；能维持眼部弹力、保持皮肤光滑。

DFerric Perchloric acid method was used to determine the content of ester-series alkaloid, and acid dye colorimetry was used to determine the content of total alkaloid in Complex Prescription Monkshood plaster.

方法分别采用改良异羟肟酸铁－高氯酸铁法及酸性染料比色法测定制剂中的酯型生物碱及乌头类总生物碱的含量。

MethodsFerric Hydroxamic acid―Ferric Perchloric acid method was used to determine the content of ester-series alkaloid, and acid dye colorimetry was used to determine the content of total alkaloid in Complex Prescription Monkshood plaster.

方法分别采用改良异羟肟酸铁－高氯酸铁法及酸性染料比色法测定制剂中的酯型生物碱及乌头类总生物碱的含量。

The experimental results showed that the composition of dry gas produced from Daqing VGO in the presence of acidic catalyst was similar to that of cracking FCC olefin enriched gasoline,and dry gas was mainly produced through monomolecular mechanism.

结果表明，大庆蜡油在酸性催化剂上反应所产生的干气组成与高烯烃催化裂化汽油相同，干气的产生主要是单分子裂化反应所造成的。

The results show that BDT can be assembled on the surface of copper electrode to form monomolecular self-assembled membrane,and the membrane can efficiently inhibit the copper base corrosion in the 3% NaCl corrosion medium and acidic solution.

实验表明：BDT能够有效地组装到铜的表面形成单分子自组装膜，BDT自组装膜能有效地抑制铜基底在3%NaCl腐蚀介质以及酸性NaCl溶液中的腐蚀行为；缓蚀效率随组装时间的延长逐渐升高并趋于稳定，在pH值较低的溶液中仍具有较好的缓蚀效果；当BDT浓度为1.0×102 mol/L、组装时间为40 h时，铜电极的腐蚀电流最小，缓蚀效率最好。

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。