查询词典 acidity

The structural and photocatalytic properties of TiO〓 as well as surface acidity were greatly improved by sulfation. SO〓〓/TiO〓 solid superacid with Hammett constant Ho less than -12.14 was prepared by treating the TiO〓 with 1.0mol. L〓 sulfuric acid solution and then calcining at 450℃ for 3h. When compared to unmodified TiO〓, the SO〓〓/TiO〓 superacid catalyst exhibited higher anatase content, smaller crystal size, higher specific surface area, centralized pore size distribution, and the blue-shifted band edge of uv-vis adsorption spectra. Furthermore, the SO〓〓/TiO〓 superacid also showed excellent reaction activity and stability for CH〓Br photocatalytic decomposition even under the moist reaction conditions. The apparent quantum efficiency of SO〓〓/TiO〓 was 10 times of that of TiO〓 catalyst for the photocatalytic degradation of bromomethane. Therefore, the SO〓〓/TiO〓 superacid catalyst is promising for practical application in environmental remediation.It was found that both L and B acid sites exist on SO〓〓/TiO〓 photocatalyst while only L acid sites on TiO〓 photocatalyst. On the basis of experimental results, the synergistic model of superacidic centers was proposed for SO〓〓/TiO〓 photocatalyst to explain the photocatalytic behavior and the mechanism of superacidifing effects, assuming that the adjacent L and B acid sites induced by SO〓〓 comprise cooperatively the superacidic center on superacid photocatalyst. The group cooperation of the superacidic center could strengthen the surface acidity, increase surface acid sites and the adsorbtion of O〓, promote separation of photogenerated electron-hole pair, enhance the interfacial transfer of charges and reversibility of water adsorption. Consequently the excellent photocatalytic activity, reaction stability and resistibility to humidity of SO〓〓/TiO〓 superacid photocatalyst may attributed to the group cooperated effect of the superacidic center on the photocatalyst.

研究结果表明：SO〓〓与TiO〓表面的结合为螯合式双配位结构；TiO〓光催化剂表面经H〓SO〓浸渍处理后，提高了表面酸性，改善了催化剂结构和光催化性能，当H〓SO〓浸渍浓度为1.0mol.L〓、烧结温度为450℃时，可制得SO〓〓/TiO〓超强酸催化剂(H〓＜-12.14)，其结构和光催化活性得到明显改善，与TiO〓相比，SO〓〓/TiO〓光催化剂的锐钛矿含量高、晶粒小、BET比表面积大、孔径分布集中、光谱吸收边蓝移，具有优异的光催化氧化活性、稳定性及抗湿性能，光催化降解溴代甲烷的表观量子效率比TiO〓催化剂提高了一个数量级，是一种有实际应用前景的高效光催化剂；由此提出了SO〓〓/TiO〓超强酸催化剂表面集团协同作用的超强酸中心模型，认为在SO〓〓/TiO〓超强酸催化剂表面，由SO〓〓诱导的相邻L酸中心和B酸中心组成了集团协同作用的超强酸中心，其集团协同作用显著地增强了催化剂表面酸性、增大了表面酸量及O〓吸附量、促进了光生电子和空穴的分离及界面电荷转移，具有可逆吸附水的性能，是SO〓〓/TiO〓超强酸催化剂具有优异的光催化氧化活性、很好的活性稳定性及抗湿性能的重要原因。

Under technological conditions such as: room temperature, current density 200 A/m^2, anolyte acidity 0.5 mol/L chlorhydric acid, acidity of catholyte 1.5 mol/L chlorhydric acid, circulation of anolyte and catholyte 40 L/h, Ni(superscript 2+) concertration 0.85 mol/L, and the average cell voltage 1.3 V, the electricity consumption of dissolving a ton of nickel base alloy is 813 kWh, and the Ni(superscript 2+) retention rate of the ion exchange membrane is more than 99.5%.

在电流密度200 A/平方公尺、阳极酸度0.5 mol/L、阴极酸度1.5 mol/L、循环量40 L/h、Ni(上标 2+)浓度0.85 mol/L左右和室温的条件下电解，平均槽电压1.3 V，电溶1 t镍合金板耗电813 kWh，阴离子交换膜对镍的截留率大於99.5%。

Based on the problems of low viscosity index and the acidity increasing in the lubricating base oil,it has been found that the unstable quality of the crude oil was the root cause to effect on the quality of the base oil by analysis for long time;the low viscosity index and the higher acidity were resulted from the low paraffinicity and the high content of aromatics,cyclane.

针对润滑油基础油相继出现的黏度指数降低、酸值升高等问题，跟踪分析了润滑油基础油质量，认为原油的变化是造成润滑油基础油质量变化的根本原因；基础油组成中烷烃含量降低，芳烃和环烷烃含量上升是其酸值上升和黏度指数下降的内在原因。

In some range,the addition of chitosan and titriable acidity after deacidification appears linear correlation,1 g chitosan can absorb 0.41 g titriable acidity, but chitosan only can absorb citric acid and malic acid, and it has no effect on quinic acid.

在一定范围内，壳聚糖的加入量与降酸后酒液的滴定酸呈线性关系，1 g壳聚糖可以降低0.41 g／L的滴定酸，但壳聚糖只能吸附主要有机酸中的柠檬酸和苹果酸，对奎尼酸无作用。

It is a organic hexahydric weak acid. In different acidity, the dissociation degree and the color of reagent solvent were different also. Determined and draw the absorption curve of reagent in varies acidity, and figured out the dissociation constant by Perisic-Janjic method; the complex ratio of the reagent and bismuth was determinated by mole ratio method and continuous variation method; The apparent stability constant of the complex was calculated, the mechanism of dissociation and coordination were discussed.

2，6—二溴4—硝基偶氮氟胂是本实验室合成的测定铋的一个较好的试剂，对其进行了进一步的研究，在用柱层析法对其进行了提纯后，测定了试剂在不同酸华东师范大学硕：l：学位论文摘要度下的吸光度和最大吸收波长，绘制了其吸收曲线，用Perisic一Janjic法计算了试剂的六级离解常数；用摩尔比法和连续变化法测定了试剂与秘形成的配合物的络合比：计算了配合物的表观稳定常数，研究了其离解和配合机理，为筛选高效有机显色剂提供了理论依据。

In the synthesis of canthaxanthin by selective catalylitic oxidating of βcarotene,CO2 was used as acidifying or alkalizing agent,which controlled reacting system acidity and protected polyene.,producing less by-products and increasing catalylitic oxidation selectivity.In the addition reaction of isoprene with hypochloric acid,1-chloro-2-methyl-3-buten-2-ol and l-chloro-2-methyl-3-buten-4-ol were made by controlling of the acidity with carbon dioxide i...

CO2作为酸碱调节剂和惰性气体，在β-胡萝卜素催化氧化合成角黄素反应中，可以控制反应体系酸性，保护原料中的双键，减少副反应发生，提高催化氧化反应的选择性；异戊二烯氯醇化生成1-氯-2-甲基-3-丁烯-2-醇和1-氯-2-甲基-3-丁唏-4-醇反应中，CO2代替有机酸作酸碱调节剂，控制次氯酸的生成速度，达到调控反应的目的，反应条件温和，不副产固体。

MethodsIn the solvent of 1 mol/L NaOH,using the reaction of the total components of water-soluble phenolic acidity in Danshen and the NaNO2-Al(NO3)3,the total components of water-soluble phenolic acidity in compound Danshen preparation(calculated with protocatechualdehyde )were determined by colorimetric spectrophotometry.

方法利用丹参中水溶性酚酸类成分与NaNO2-Al(NO3)3在碱性条件下的显色反应，比色法测定复方丹参制剂中水溶性酚酸的总量。

MethodsIn the solvent of 1 mol/L NaOH, using the reaction of the water-soluble phenolic acidity in Radix Salviae Miltiorrhizae and the NaNO_2-Al(NO_3)_3, the total components of water-soluble phenolic acidity in Radix Salviae Miltiorrhizae injections and drip solution(calculated with protocatechualdehyde) were determined by colorimetric s...

方法利用丹参中水溶性酚酸类成分与亚硝酸钠和硝酸铝溶液在碱性条件下的显色反应，比色法测定该两种制剂中水溶性酚酸的总量。结果原儿茶醛在3.336~14.46mg/L范围内呈良好的线性关系，回归方程为：A=0.02777C+0.01279(r=0.9996)，加样平均回收率为100.8%，RSD为0.96%。结论该法简便快速，结果准确，重现性好，可用于该制剂的质量控制。

The logarithm difference values of partition coefficients of the compounds in butyl ether/water and in cyclohexane/water system were used for the measurement of the Lewis acidity, while the logarithm difference values of partition coefficients in trichloromethane/water and in tetrachloromethane/water system were used for the measurement of the Lewis basicity, and they were used successfully to differentiate the relative strength of Lewis acidity and basicity for 59 benzene and its derivates.

以化合物在正丁醚/水和环己烷/水溶剂体系中分配系数的对数差作为酸性指数，以其在氯仿/水和四氯化碳/水溶剂体系分配系数的对数差作为碱性指数，提出了一种新的度量有机物Lewis酸碱性的方法，按此方法成功地区分了59种苯系物Lewis酸碱性的相对强弱；并成功地将上述酸碱性指数引入定量结构—性质/活性相关研究之中，探讨了苯系物的正辛醇/水分配系数、水溶解度和土壤有机碳吸附系数等常见理化性质与其Lewis酸碱性间的相关性并建立了相应的定量模型，发现它们之间存在良好的相关性。

Firstly, based on the acidity balance equation in ecosystem, together with the steady state mass balance equations of sulphur and nitrogen, formulae for calculating critical loads of not only acidity and sulphur, but also acidifying nitrogen and nutrient nitrogen were educed.

基于原有的生态系统酸度平衡关系，并结合临界状态下硫和氮的稳态质量平衡，推导出计算酸度、硫、酸化氮和营养氮临界负荷的公式。

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。