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[求助]
英语翻译成汉语，比较急，麻烦大神帮一下
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The PEO teeth, grafted to the PAA backbone, exhibit three important merits. First, the presence of the PEO teeth, attached at random intervals along the PAA backbone, prevents large configuration changes in the solution or on the alumina surfaces in response to varying salt ionic concentrations. Second, the PEO teeth protect the underlying PAA backbone from ionic interactions that promote an aggregation of pure PAA species in solution or PAA-coated a-Al203 particles in suspension. Third, the PAA-PEO forms a double-decked adsorption configuration on the alumina surface. One is a PAA segment anchored in the alumina surface, and another is a charge-neutral PEO teeth grafted on the PAA backbone. This kind of double-decked adsorption configuration increases the adsorbed layer thickness, and it also increases the steric hindrance repulsion, therefore PAA- PEO has better dis-persion compared to PAA. Figure 5 could be used to explain that the salt ion influenced the rheological properties of the PAA-a- A1203 suspension, and the PAA-PE0-a-Al203 suspension hindered this kind of effect. Figure 5(a) shows that, in the PAA-a-Al203 suspension system, the negatively -charged carboxylate groups (COCT) could combine with the posi-tively-charged Ca2+，and one Ca2+ could combine with two PAA segments by its two positive charges, so it could produce the Ca2+ bridging that led to a rapid aggregation of the alumina suspension, and therefore, the suspension became unstable. Figure 5(b) also shows that, in the PAA-PE0-a-Al203 suspension system, the negatively- charged carboxylate groups (COCT) also could combine with positively-charged Ca2+，but the Ca2+ could not combine with the two PAA segments due to the presence of the charge-neutral PEO teeth. These PEO teeth, grafted in the PAA backbone, produced a dense protec-tive comb layer, avoiding Ca2+ bridging, which led to rapid aggregation of the alumina suspension. The PAA-PE0-a-Al203 suspension has the very strongly resistant electrolytic performance. |
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LifePursuit
木虫之王 (文学泰斗)
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语无伦次: 金币+20, 翻译EPI+1, ★★★★★最佳答案 2014-12-15 21:09:16
语无伦次: 金币+20, 翻译EPI+1, ★★★★★最佳答案 2014-12-15 21:09:16
| 接枝到PAA 骨架上的PEO“牙”表现出三个重要的优势。首先，在PAA 骨架上以随机间距粘附的PEO“牙”的存在能够防止（PAA 骨架）在溶液中或Al203表面上因响应不同盐离子浓度而造成的较大构型变化。其次，PEO“牙”的存在能够防止纯PAA 骨架在溶液中、或PAA-包裹的alpha-Al203粒子在悬浮液中因为离子相互作用而造成的团聚。第三，PAA-PEO在Al203表面上形成一种双层吸附构型。其中一层是锚固于Al203表面上的PAA片段，而另一层则是接枝于PAA 骨架上电中性的PEO“牙”。这种双层吸附构型增加了吸附层的厚度，同时也增加了空间位阻（排斥作用），因而PAA-PEO与纯PAA相比具有更好的分散性。图5能够用来解释盐离子对PAA-alpha-Al203悬浮液流变性质的的确具有影响，而PAA-PE0-alpha-Al203悬浮液则阻止了这一影响。图5(a)表明在PAA-alpha-Al203悬浮液体系中电负性的羧基可以与电正性的Ca2+离子结合，而一个Ca2+离子（具有两个正电荷）可以与两个PAA片段结合，从而产生Ca2+桥接作用导致alpha-Al203悬浮液的快速团聚，使其变得不稳定。图5(b)表明在PAA-alpha-Al203悬浮液体系中电负性的羧基也可以与电正性的Ca2+离子结合，但因为存在电中性的PEO“牙”使得Ca2+离子无法与两个PAA片段相结合。接枝到PAA 骨架上的PEO“牙”产生一层致密的保护层从而避免了Ca2+桥接作用（以及由此引起的alpha-Al203悬浮液的快速团聚）。PAA-PE0-alpha-Al203悬浮液因此表现出极强的抗电解质性质。 |
2楼2014-12-14 19:57:21
