两性离子

The crystallization thermodynamic data, such as solubility, metastable zone and other basic data of 6APA were measured based on experiments, which demonstrated that as an ampholyte 6APA can exist in solution as a combination of anionic, zwitterionic and cationic species.

实验数据证明6APA是一种两性化合物，其结构以及溶液行为类似于普通氨基酸，在溶液中以两性离子、正离子以及负离子的形式共存，通过改变溶液的pH值，可以极大地改变6APA的溶解度，这就是6APA等电点沉淀的原理。

Flavin 2 is most likely present in its zwitterionic form or as its carboxylate ion.

黄素二是目前最有可能在其两性离子的形式或作为其羧酸离子。

At an intermediate pH value, an amino acid acts as a dipolar ion, or zwitterion, which has no net charge.

在pH值适中的时候，氨基酸可作为偶极离子，或两性离子，它不带电。

Zwitterion An ion with both a positive and a negative charge.

两性离子：既带有正电荷又带有负电荷的离子。

The results show that, with the increase in ionic strength, the adsorbed amount of taurine on the resin D290, the distribution coefficient λ and the fraction of zwitterion Tau(superscript ±) all decrease, while the pH value of the solution at the equilibrium and the content of anionic taurine Tau(superscript -) increase. Moreover, it is found that, at a certain taurine concentration, the increase in ionic strength may improve the selectivity of the anion resin for taurine.

研究结果表明：(1)随着溶液离子强度的升高，阴离子树脂对牛磺酸的平衡交换吸附容量逐渐降低，牛磺酸在树脂上的分配系数λ逐渐下降；(2)随着溶液离子强度增大，达到平衡时液相的pH值升高，溶液中牛磺酸阴离子Tau含量迅速增加，而牛磺酸两性离子Tau含量迅速降低；(3)在一定的牛磺酸浓度范围内，溶液离子强度增大，有利于提高离子交换树脂对牛磺酸的选择性。

In the tests, the nonionic type polyacrylamide, the anion type polyacrylamide and the zwitterion type polyacrylamide, and the compounding of the poly-aluminum chloride/PHP and the calcium chloride (CaCl2)/NPAM were used as flocculation agents.

选择聚合氯化铝/阴离子型聚丙烯酰胺、氯化钙（CaCl2）/非离子型聚丙烯酰胺组合与NPAM、PHP、两性离子型聚丙烯酰胺作为絮凝剂，在对道清选煤厂水采筛下原生煤泥和浮选尾矿的煤泥水进行组合药剂絮凝实验的基础上，考察了pH对煤泥水絮凝沉降的影响。

This problem can be solved by adding proper amount of 2- ethane sulfonic acid to adjust the pH of the eluent so as to prevent the heteropoly acid from discomposing.

实验通过在常规淋洗液中加入适量两性离子后，调节淋洗液的pH为中性，从而能准确测定杂多酸中磷酸根氯离子和硫酸根的含量值。

The contribution of electrostatic interaction to the transfer volumes is predominant. The reduction in the electrostriction with increasing the concentration of salts was confirmed by the decreased hydration number.

氨基酸两性离子端基和阴阳离子间的静电作用对迁移体积的贡献是主要的，静电作用削弱了两性离子带电中心对周围水分子的电致收缩效应，造成氨基酸的理论水化数随盐溶液浓度的增加而减小。

The concentration of liquid hydrocarbon B is 10%.the dosage of hydrophobe is 15%~20%. The condensation and used environment of defoaming agent were studied ,the experiments show that self-made defoamer can be the same with many bubbly systems,such as anion, zwitterions, Nonionic bubbly liquid et al.and it can be used from acidity to alkalescence conditions.the fitting dosage is 9‰～10‰to polyester,6‰to siloxane-polyester copolymer,and 3‰to mulriple defoamer.

对消泡剂的投加浓度、适用环境等作了相关应用研究，结论为：消泡剂适用的起泡体系较广，阴离子、两性离子、非离子型起泡液均可使用；适用PH值范围可从酸性至弱碱性，适宜加入量为(以占起泡体系的体积分数计)：聚醚酯消泡剂9-10‰，有机硅改性聚醚酯消泡剂6‰，复配消泡剂3‰。

New formula of drilling mud density of the control wellbore closed rate in salt bed .;2. Application of ternary copolymer salt-resisting fluid loss reducer in salt bed of Carboniferous system in Tahe oilfield.;3. The components of amphoteric polymer salt tolerance mud have been introduced, and the field operation technology drilling through thick salt bed by using amphoteric polymer mud system has been summarized.

论述了盐对泥浆胶体性质的影响机理，介绍了两性离子聚合物抗盐泥浆的组成，总结了两性离子聚合物泥浆体系钻穿大段盐层的施工工艺及现场应用中常见的问题，指出抗盐泥浆的基础是保证处理剂对粘土颗粒足够的护胶能力，而手段是提高抗盐处理剂在泥浆中的含量。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。