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liuyunruoyan木虫 (著名写手)
小小木虫
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【求助】一段英文翻译，（英译汉）【有效期至2009年4月3日晚】
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Transfer from Light to Heavy Water Ben-Naim21 laid the foundation for the estimation of the effects of ions on the structure of water in terms of the changes in the average number of hydrogen bonds that characterized this structure (section 3.2). The pair potential between water molecules is written as a sum of two terms: one that describes both the short-range (repulsion) and longrange (multipole) interactions and another that describes the hydrogen bonding as the product of the hydrogen bond energy eHB and the geometrical factor 0 ≤GHB ≤ 1, specifying whether a hydrogen bond exists or not (section 3.1). The introduction of a solute particle S into H2O and into D2O is associated with a difference in its standard chemical potentials in these two kinds of water, ΔμS∞ HD, that depends solely on changes in the hydrogen bonding structure of the water, in view of the very similar properties of molecules of these two kinds of water with respect to solute-solvent interactions (section 3.2). Therefore, this difference can be written as ΔμS ∞HD=ΔHDeHBΔGHB (22) Here ΔHDeHB is the difference in the strengths of the hydrogen bonds in D2O and H2O obtained from the sublimation enthalpies of the ices (eq 6) and ΔGHB is the change in the average total geometrical factors over all the configurations of the N water molecules of either kind caused by the introduction of a particle of S: ΔGHB=(2/N)[(ΣNGHB)S-(ΣNGHB)0] (23) The left-hand side of eq 22 is an experimentally measurable quantity (from solubilities, EMF data, etc.); hence, ΔGHB, the effect of the solute S on the (hydrogen bonded) structure of water, can be determined. Nonionic solutes, such as argon or methane, are known from several approaches to enhance the structure of water and have positive values of ΔGHB, diminishing with increasing temperatures, as is expected (section 3, Table 1).21 Application of this treatment to ionic solutes was also tentatively made by Ben-Naim21 and was subsequently taken up by Marcus and Ben-Naim.44 The most satisfactory description of the structure of water appears to be in terms of the average number of hydrogen bonds per water molecule existing in it (section 3). It is, therefore, deplorable that the data for ΔμS ∞ HD of electrolytes are rather unsatisfactory, not to speak of the lack of definite data for ascribing ΔμS ∞ HD to individual ions. The values of ΔμS ∞ HD that have been measured for various electrolytes are small, and even in a recent electrochemical study,193 they are of the same order as their uncertainties. The “best” values available were summarized by Marcus,208 ranging from ΔμS ∞ HD/J mol-1 =-950 for Bu4N+ to 1200 for Ba2+, at 25 °C with probable errors of ±100. According to eq 6, ΔHDeHB=-742 J mol-1 at 25 °C, but the value of -929 J mol-1 was previously employed.201,205,208 The better established values of ΔμS ∞HD for the nine alkali metal and halide ions, based on equalizing the values for Ph4As+ and BPh4-, and incidentally also for K+ and Cl-, should be taken for correlations with well established quantities describing the water structural effects of ions, such as Bη and ΔSstruc. The resulting expressions, calculated with ΔHDeHB = -742 J mol-1 in eq 22, are ΔGHB=-(0.68±0.14)+(5.95±1.74)(Bη/M-1) (24) with a standard error of the fit of 0.3 units and ΔGHB=-(0.18±0.08)-(10.22±1.26) × 10-3 (ΔSstruc/J K-1 mol-1) (25) with a standard error of the fit of 0.2 units. In this manner, values of ΔGHB can be generated for a large number of ions. These dimensionless values, of course, do not describe the ionic water structural effects any better than the viscosity Bη coefficient and the structural entropy ΔSstruc, themselves, but they have the form suggesting the theoretical basis provided by Ben-Naim in terms of the effect of the ions on the extent of hydrogen bonding in dilute electrolyte solutions.21 如上，文中公式的上下角标不能正确显示，请忽视，多谢，万分着急！ |
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mayong11
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liuyunruoyan(金币+100,VIP+0):非常感谢！很及时，不知道兄弟有没有时间再来一段？ 4-2 17:18
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Naim21奠定了离子对水的结构中包含氢键这种特点的平均氢键数的影响的估计的基础（第3.2节）。两人水分子之间的对势被定义为两个条件：一，描述了短距离（斥力）和长距离 （多极）的相互作用和另一描述是以氢键能eHB的形式描述氢键，依据几何因素0 ≤eHB≤ 1 ，说明是否存在氢键（第3.1节） 。在H2O和成D2O分别引入溶质粒子S的这两种水具有不同的标准化学势， ΔμS ∞HD，这完全取决于水结构中氢键的变化，鉴于这两种水对溶质溶剂的相互作用非常类似性质（第3.2节） 。因此，这种差异可以描述为： ΔμS ∞HD=ΔHDeHBΔGHB (22) 这里ΔHDeHB是从冰的升华焓得到的，区别是在D2O和H2O中氢键的长度不同，（eq 6 ）和ΔGHB是表示引入一个粒子S后，总几何因素对所有配置的N水分子的平均变化，具体描述为： ΔGHB=(2/N)[(ΣNGHB)S-(ΣNGHB)0] (23) 左边的eq 22 是给出的一个实验测量数值（从溶解度，电磁场数据等; 而ΔGHB代表溶质粒子S对水的（氢键）结构的影响，它由非离子溶质如氩气或甲烷确定。非离子溶质被认为由几个途径可以提高水的结构和预计随着温度的降低，其产生的ΔGHB 的正值逐渐缩小（第3节，表1 ） 这种处理的离子溶质应用的初步是由ben Naim 提出的，随后被 Marcus 和ben Naim采用，水结构最令人满意的描述是在水分子中存在规定的平均数目的氢键（第3节）因此，令人遗憾的是，电解质的ΔμS ∞HD数据相当不能令人满意，而不是说对于个别离子没有明确的ΔμS ∞HD数据。被测量到的各种电解质的ΔμS ∞HD数据是很小的，甚至在最近的电化学研究中，他们都是被同样的认为不确定性。 “最好”的数据是由Marcus总结提供的，即从Bu4N +的ΔμS ∞HD/ J摩尔- 1 =- 950, 到钡离子的1200，在25 ° C的可能误差为± 100 。根据eq 6 ， 在25 ° C ΔHDeHB =- 742 J摩尔- 1 ，但以前认为是-929 J摩尔- 1。基于均衡的值Ph4As +和BPh4 - ，9碱金属和碱土金属卤化物离子的ΔμS ∞HD数据被较好的证实，并顺便证实了K +和Cl -的ΔμS ∞HD数据，应该采取这些相关的较好的确定值来描述离子对水结构影响，如Bη和ΔSstruc 。通过ΔHDeHB = -742 J摩尔- 1，由此产生的表现形式eq 22是 ΔGHB=-(0.68±0.14)+(5.95±1.74)(Bη/M-1) (24) 与标准误差0.3单位和 ΔGHB=-(0.18±0.08)-(10.22±1.26) × 10-3 (ΔSstruc/J K-1 mol-1) (25) 与标准误差0.2单位。通过这种方式，ΔGHB的数值可以由大量的离子产生。当然这些无量纲值，描述离子对水结构的影响比他们自己的粘度系数Bη和结构熵ΔSstruc 没有任何优势，但是BEN 对在稀电解中，离子对的氢键程度的影响提出了理论依据。 [ Last edited by mayong11 on 2009-4-2 at 12:05 ] |
2楼2009-04-02 11:11:44