查询词典 acidic

It may be concluded that the Fe_2O_3/MgO sites,localized on Mg atoms,are acidic(presumably Lewis-type) in nature and that these results provide evidence for the heterolytic decay of the hydroperoxide to phenol and acetone.It was found that the activity of the catalysts had relationship with their redox behaviour.

氧化催化剂的活性与其氧化还原性具有一定的相关性，催化剂还原性越好，越容易导致异丙苯过氧化氢分解，进而促进异丙苯的转化。

The reaction under the catalysis of 10%Fe_2O_3-MgO stoped quickly.It may be concluded that the Fe_2O_3/MgO sites,localized on Mg atoms,are acidic(presumably Lewis-type) in nature and that these results provide evidence for the heterolytic decay of the hydroperoxide to phenol and acetone.

采用共沉淀法制备了催化剂M_xO_y-MgO(M=Ni、Fe、Co、Cu)，并用X射线衍射仪、程序升温还原(H_2-TPR)以及X射线光电子能谱等对催化剂进行了表征，并与其催化性能进行了关联。

The results indicated that 40% ethanol and water can dissolve Berberis heteropoda pigment better; the pigment is stable in acidic condition; iron ion can increase the absorbency of the pigment; the influences of reducing agent is greater than oxidizer＇s.

结果表明，小檗色素在40％的乙醇溶液及水中的溶解效果最好；在酸性条件下色素较稳定；铁离子对其有增色作用；氧化剂、还原剂对色素稳定性均有影响，其中以还原剂影响较大。

The catalysis of heteropoly acids in solid state has received much attention owing to their unique acidic and redox activities.

杂多酸作为固体酸催化剂以其优异的催化性能被广泛的应用在酸催化和氧化催化的各种反应体系中。

In the absence of organic solvent and phase-transfer reagent, the catalytic oxidation of cyclo- hexene to adipic acid with aqueous 30% hydrogen peroxide can be achieved in the presence of tungstic acid/acidic organic additive.

以钨酸/有机酸性添加剂为催化体系，在无有机溶剂、相转移剂的情况下，催化 30%过氧化氢氧化环己烯合成己二酸。当钨酸∶有机酸性添加剂∶环己烯∶过氧化氢=1∶1∶40∶176(摩尔比，钨酸用量为 2.5 mmol)时，使用有机酸性添加剂考察钨酸的催化性能，结果表明以钨酸/间苯二酚催化氧化环己烯的催化效果最优，反应 8 h 时己二酸分离产率达 90.9%、纯度为～100%；而不使用有机酸性添加剂时，己二酸分离产率只有 72.1%，产品纯度为 96.2%。

Six experimental stages were designed in our procedure, those are:(1) metabolite recovery and tested sample preparation: the metabolites were recovered by Amberlite XAD-2 absorption, followed by MeOH elution and solvent concentration;(2) antioxidant detection and strain selection: samples were quantitatively analyzed by the inhibition effects on formation of lipid peroxides and TBARS to screen the strains able to produce antioxidants. According to the established screening methods, we chose out a strain of actinomycetes, designed as AMBL-029C;(3) antioxidant purification: the fermentation broth was recovered by a series of separation techniques including centrifugation, Amberlite XAD-2 absorption, followed by MeOH elution and a successive TLC purification. The resulting primary purified compound [temperately designed as AMBL-029C-TS] was further analyzed by HPLC to monitor its purity;(4) physical-chemical characteristics: judging from the acid-base fractionation experiments, and the pH and temperature stability tests, the compound was deduced to be a acidic compound with the properties of low polarity and highly pH and temperature stable;(5) mechanism of the antioxidant: in comparison with some other known antioxidants, TS was subjected to investigate its antioxidant mechanism, together with BHT,-tocopherol, as well as two streptomyces metabolites, homogentisic acid and -phenylpyruvic acid, which were previously isolated as the natural antioxidants in our laboratory.

针对本实验目的，我们设计了以下的实验步骤﹔（1）二次代谢物回收及检测样本处理：我们将发酵所得的培养上清液，利用疏水吸附性树酯Amberlite XAD-2吸附回收，并以甲醇溶离及真空减压浓缩脱水等方式处理，以取得提供抗氧化活性筛选之检测样本；（2）抗氧化活性检测及菌种筛选：以「过氧化脂质」和「硫丙二醯尿」的生成量进行定性定量分析以作为抗氧化物质生产菌筛选之用；经此筛选程序，我们选获了具有抗氧化物质高生产力的菌株，命名为AMBL-029C；（3）抗氧化物质的分离纯化：针对生产菌株的发酵回收处理液，以矽胶薄层色层分离法经物质层析纯化后，并以高效能液相层析法(High performance liquid chromatography；HPLC)分析物质可得一初级纯化物质，命名为AMBL-029C-TS；（4）抗氧化物质的物理化学性质分析：由酸碱转溶（acid-base fractionation）实验得知，此抗氧化物质属於中低极性的强酸性物质，对温度（37℃-100℃）及酸碱度（pH3.0-13.0）均表现出高稳定性；（5）在抗氧化机制探讨方面，我们针对数种不同的抗氧化机制进行探讨，即： 1。

In acidic aquatic environment, hydrotalcite and its calcined product can also play a role in neutralizing H(superscript +) ions and sorbing anions.

在酸性环境下，水滑石及其焙烧产物在对阴离子的吸附过程中都有中和酸性溶液的作用。

Chemically, fluoroquinlones are an amphoterics molecule processing major ionizable groups, a basic piperazine amine and acidic carboxyl. The form of drugs was greatly affected by the acidity in aqueous solution. Thus the effect of pH values in aqueous solution on the fluorescent properties of fluoroquinolones was studied in details, the spectral properties of each form was characterized. It was found that the fluoroquinolones exhibit weak fluorescence in strong basic solution.

氟喹诺酮类药物分子结构中既有羧基，又有哌嗪氨基，它们所处环境的pH值对其存在型体有很大影响，因此我们详细研究了水溶液的pH值对该类药物光谱特性的影响，并对于各型体光谱特征进行归属，发现强碱性溶液中其发光较弱。

A chromium free conversion coating at least equivalent in corrosion protective quality to conventional chromate conversion coatings can be formed on metals, particularly cold rolled steel, by a dry-in-place aqueous acidic liquid comprising: a component of anions, each of said anions consisting of at least four fluorine atoms and at least one atom of an element selected from the group consisting of titanium, zirconium, hafnium, silicon, and boron, and, optionally, ionizable hydrogen atoms, and optionally, one or more oxygen atoms; a component of cations of elements selected from the group consisting of cobalt, magnesium, manganese, zinc, nickel, tin, zirconium, iron, and copper; the ratio of the total number of cations of this component to the total number of anions of component being at least 1:5; sufficient free acid to give the composition a pH in the range from 0.5 to 5.0; a component selected from the group consisting of phosphorus-containing inorganic oxyanions and phosphonate anions; and a component selected from the group consisting of water-soluble and water-dispersible organic polymers and polymer-forming resins and, preferably, also including a component selected from the group consisting of tungstate, molybdate, silicotungstate, and silicomolybdate anions.

通过对包含以下成分的含水酸性液体进行干燥，可以在金属上形成无铬的转换涂层，该涂层与普通铬酸盐转换涂层相比，至少在抗腐蚀质量上等效：$_一种阴离子成分，所述各个阴离子包括至少4个氟原子，至少选自钛、锆、铪、硅与硼元素中的1个原子。任选地可离解的氢原子，任选地1个或多个氧原子；$_一种选自钴、镁、锰、锌、镍、锡、锆、铁与铜元素的阳离子成分，上述成分的阳离子总数与成分内的阴离子总数之比至少为1∶5；$_足够的游离酸以使该组合物的pH值在0.5～5.0的范围内；$_一种选自含磷的无机含氧阴离子与膦酸盐阴离子的成分；$一种选自水溶性与水可分散性有机聚合物与聚合物形成的树脂的成分，优选还包括一种选自钨酸盐、钼酸盐、钨硅酸盐与钼硅酸盐阴离子的成分。

The synthesis of isoamyl acetate with the solid super acidic catalyst of S2O827TiO2-Al203 is investigated. The kinetic parameters of reaction are measured at 94℃, 100℃ and 106℃ respectively and the kinetic equation is thus built, which are compared with those of the reaction without catalyst.

文章研究了以固体超强酸S2O82-/TiO2-Al2O3为催化剂合成乙酸异戊酯的反应，在反应温度分别为94℃、100℃及106℃下，测出合成乙酸异戊酯的动力学方程参数，建立了动力学方程式，并与无催化剂时酯化反应的活化能及动力学方程式进行了比较。

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。