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双语推荐：氢键

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把关联模型（association models）推广应用到聚异丙基丙烯酰胺（PNIPAM）高分子凝胶体系,研究PNIPAM-水的氢键和水-水的氢键在高分子凝胶体积相变中的作用.首先通过分析凝胶体积分数与温度的关系发现,由于两种氢键作用,随着温度变化PNIPAM凝胶出现体积相变,表明在体积相变过程中两种氢键都起着重要作用.其次,对旋节线的研究发现,PNIPAM凝胶体积相变中出现的下临界共溶温度（LCST）现象也是由于PNIPAM-水氢键和水-水氢键共同作用的结果.
We presented a theory to study the volume phase a transition in Poly (N-isopropylacrylamide) (PNIPAM) gels. Our theory model includes the consideration of PNIPAM -water and water -water hydrogen bonds. On basis of our theory approach, we investigated the PNIPAM gels volume fraction as a function of temperature. It is clearly indicate, because of two types of hydrogen bonds, PNIPAM gels present volume phase transitions. The calculated spinodal curves reveal, also because of both PNIPAM-water and water-water hydrogen bonds, the presence of lower critical solution temperature (LCST).

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概述了近年来为揭示水分子簇存在形态的成因所做的理论和实验研究,指出除范德华力外,氢键和似共价键是水分子间的主要作用力.总结了水分子簇中氢键的四种作用方式,包括协同效应、氢键的转动、氢键的振动以及氢键变换;分别讨论了这四种作用方式以及似共价键对水分子簇存在状态的影响,最后对该领域的研究前景作了展望.
Theoretical and experimental studies that reveal the formation of water clusters have been summarized. Besides van der Waals force, hydrogen bonds and quasi-covalent bonds between water molecules are major forces. Four kinds of kinetic motions of hydrogen bonds in water clusters are outlined, including cooperative effect, rotation, vibration and inter conversion, and the effects on the structure of water clusters caused by quasi-covalent bonds and H-bond kinetic motions are explained in detail. Finally, the perspective in this research field is also discussed.

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通过氢键调节作用建立一种快速分离与鉴定人工色素的薄层色谱法。以石油醚-二氯甲烷（7：3,V/V）为基础展开体系,分别对硅胶进行接枝改性和在基础展开体系中添加氢键调节剂,再对人工色素进行薄层色谱检测分析。结果表明：相较于硅胶,改性硅胶的氢键密度明显增大,其氢键密度随着改性剂质量浓度的增加而增大;主链型改性剂和氢键调节剂的引入增加了固定相、流动相与人工色素间形成氢键的可能性,改变了人工色素的Rf值。
This article establishes a thin layer chromatography (TLC)for the fast separation and iden-tification of synthetic pigment by hydrogen-bonding effects.Based on the conditions of petroleum ether-methylene chloride (7∶3,V/V),TLC detection and analysis on synthetic pigment was carried out by grafting hydrogen-bonding modifier onto silica gel and adding hydrogen bonding regulator to based system respectively.The results suggest that hydrogen-bonding density of modified silica gel is signifi-cantly higher than that of silica gel and increases with modifiers mass concentration.Main chain modi-fier and hydrogen-bonding eluent increases the possibility of hydrogen-bonding between synthetic pig-ment and stationary phase,as well as mobile phase,which changes the Rf value effectively.

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在ABEEMσπ/MM浮动电荷模型下，为了防止电荷过度极化，提高力场的准确性，引入了氢键拟合函数klp，H（Rlp，H）在氢键相互作用区域代替总校正系数k来描述氢键相互作用。选取了8个模型小分子二聚体，通过拟合在氢键两个区域之间不同距离时从头计算结果的结合能，来拟合ABEEMσπ/MM方法下的氢键拟合函数。应用该氢键拟合函数在ABEEMσπ/MM方法下计算小分子二聚体的结合能，与从头算方法得到的结合能有很好的一致性。同时对具有同样类型氢键的其他二聚体的结合能进行了计算，与从头算结果相近，说明这些函数具有良好的可转移性。
In order to prevent the excessive polarization of the charge and improve the accuracy of the force field in ABEEMσπ/MM fluctuating charge model ,we have introduced a hydrogen bond fitting function klp,H ( Rlp,H ) in the hydrogen bond interaction region instead of the total correction coefficient k to describe hydrogen bonding interactions .Eight small molecular dimer models are selected .Then the hydrogen bond fitting functions of ABEEMσπ/MM model are fitted by the results of binding energy of the hydrogen bonds between the two regions at different distances in ab initio method .It shows that the binding energy of small molecular dimer models by applying the hydrogen bond fitting functions in ABEEMσπ/MM method is similar with the result in ab initio method .The binding energy of dimer containing the same type of hydrogen bond is calculated in ABEEM σπ/MM method.The results are similar with the results of ab initio method .It shows that these functions have good transferability.

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运用 AIM理论在 B97D 水平上计算了2-丁炔-1，4-二基二（2，3，4，5，6-五氟苯基碳酸酯）1，2-丁炔-1，4-二基二（4-氟苯基碳酸酯）2及2-丁炔-1，4-二基二（2，3，4，5，6-五氟苯氨基甲酸酯）3中的分子间有机氟 C -H…F -C 氢键．这些分子间氢键为闭壳相互作用．尽管晶体1中 H…F 距离接近经典氢键，但是该有机氟氢键仍为弱氢键．NBO 分析表明，研究的有机氟 C -H…F -C 氢键存在明显的电荷转移，用电荷转移合理地解释了分子1采取顺式结构．
The intermolecular C-H…F-C hydrogen bonds in crystalline but -2 -yne -1 ,4 -diyl bis(2, 3,4,5,6 -pentafluorophenylcarbonate)1 ,but -2 -yne -1 ,4 -diyl bis(4 -fluorophenylcarbonate)2,and but -2 -yne -1 ,4 -diyl bis(2,3,4,5,6 -pentafluorophenylcarbamate)3 are characterized by using AIMtheory at the B97D level.Criteria based on a topological analysis of the electron density were applied.These intermolecular C-H…F-C hydrogen bonds present typical properties of closed -shell interaction.Our study revealed that organic fluorine hydrogen bond in crystalline 1 is still weak although the distance of H…F is extremely short.NBO analyses indicate that charge transfer (nF→σ*C-H)is significant even for such weak C-H…F-C hydrogen bonds.The significantly large stabilizing role of charge transfer in crystalline 1 compared with 2,3 gives an explanation for the syn -conformation of organic molecule 1 .

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在B3LYP/6-31++G水平下,利用密度泛函理论方法优化了N-甲基甲酰胺单体和氢键体系NMF-nH2O(n=1,2,3)的基态几何构型;用含时密度泛函理论方法计算了N-甲基甲酰胺单体和氢键体系NMF-nH2O(n=1,2,3)在不同电子激发态的跃迁能、振子强度和电子吸收光谱.结果表明,随着结合水分子个数的增加,氢键强度是加强的.分子间氢键引起电子吸收光谱发生红移,光谱红移程度与氢键加强的程度一致.
The ground-state geometric optimizations of the isolated N-Methylformamide and the hy-drogen-bonded NMF-nH2 O(n=1 ,2 ,3) complexes considered here were carried out using the density functional theory (DFT ) method with B3LYP hybrid functional and the 6-31+ + G basis set .The time-dependent density functional theory (TDDFT ) method with B3LYP hybrid functional was used to calculate the electronic transition energies and corresponding oscillation strengths as well as the absorption spectra of all the isolated N-Methylformamide and the hydrogen-bonded NMF-nH2 O(n=1 ,2 ,3)complexes .Form the TDDFT method result ,we depicted the changes of different hydrogen-bonded complexes the electronic absorption spectra shift and hydrogen-bonding dynamics ,hydrogen bond strengthening can bring the relative electronic absorption spectra redshift ,the electronic absorp-tion spectra redshift is consistent with the mechanism of the hydrogen bond strengthening .

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煤结构中存在的大量氢键对其化学结构和性质具有重要影响。为了研究煤在冲击破坏过程中氢键的变化。设计落锤循环冲击系统，实现对煤样的循环定量冲击。利用红外光谱仪进行光谱分析。研究得出东庞1/3焦煤主要的氢键类型是free OH groups ，OH……π，OH……OH ，cyclic OH tetramers和OH……N以及它们随冲击破坏的变化规律。在冲击力的作用下，煤体分子间氢键吸收强度变化非常明显，自由羟基也在冲击作用下发生机械力化学反应。对红外光谱进行高斯函数拟合分峰，发现各类氢键吸收强度随着冲能量的增加而减小，但其趋势在放缓。统计两者关系，得到各类氢键的光谱吸收强度与冲击能量的拟合方程，两者符合幂函数关系。对比拟合方程的幂指数，得出氢键在受冲击破坏时发生变化的敏感性顺序：free OH groups＞cyclic OH tetramers＞OH……N＞OH……π＞OH……OH。
There are many hydrogen bonds in coal ,which affect the chemical structure and properties of coal . FTIR has been applied to the characterization study of the hydrogen bonds of Dongpang coals ,which were un-der drop weight impact .There exists five kinds of hydrogen bonds in the coal:free OH groups ,OH……π ,OH……OH ,cyclic OH tetramers and OH……N .Absorption strength of intermolecular hydrogen bonds markedly de-clined after impact .Free OH groups mechanical-power chemical reacted in drop weight impact testing .The in-frared spectrum were curve-resolved into their component bands .The absorption strength of various hydrogen bonds decreased with the increase of impact energy ,but the trend was slowing .By statistical relationship be-tween then ,we find then complying with power function relationship .By comparing the exponents of fitted e-quations ,we concluded that failure sensitivity sequence of hydrogen bonds to the impact :free OH groups>cy-clic OH tetramers>OH……N>OH

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多元醇在一定温度下发生固-固相变,大量文献都报道了它们的固-固相变焓、相变温度以及相图.本文以红外光谱测试结果以及量热实验结果为基础,探讨了新戊二醇/季戊四醇二元体系的固-固相变焓与氢键的关系:二元体系中部分分子间氢键变弱,变弱的氢键更易于断裂;温度上升到一定值,新戊二醇在季戊四醇中的相向塑性晶体相相变时保留下来的氢键断裂,形成二元体系的量热曲线的第二个吸收峰;高新戊二醇浓度的二元体系,可能保留下来的氢键数量少,第二个吸收峰对应的焓值小,但保留的氢键受新戊二醇影响更大,第二个吸收峰对应的温度更低.
Many polyalcohols can change from one crystal structure to another in solid state at certain temperatures. A lot of papers reported their phase transition enthalpy, transition temperatures, and phase diagrams. This paper investigates the relation between transition enthalpy and hydrogen bond for the NPG (Neopentylglycol) and PE (Pentaerythritol) binary system on the basis of infrared spectrum experimental data and calorimetric results. It is shown that in the binary system some of the associated hydrogen bonds become weaker and are easier to break up. When temperature rises to a certain value, the hydrogen bonds, which retain in the course of phase transformation from the phase of NPG in PE to the plastic phase, will break up and form the second endothermal peak on the calorimetric curve. The number of retained hydrogen bonds is larger for the binary system NPG/PE with higher NPG concentration, and as a result, the corresponding enthalpy for the second endothermal peak is larger. While

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为研究少量乙醇分子对纯水中氢键作用的影响,测量了0~10%体积浓度区间乙醇-水溶液和纯水中羟基伸缩振动的激光拉曼光谱,并根据不同样品拉曼光谱间的差分光谱分析了低浓度溶液中乙醇分子的水合作用。研究结果表明:当向纯水中加入少量乙醇分子至4%体积浓度的过程中,水分子的四面体氢键网状结构得到扩大,同时乙醇分子疏水基团周围的水分子间氢键作用也得到加强;随着溶液中乙醇浓度的增加,乙醇分子间由于疏水水合作用逐渐聚集到了一起,造成溶液中疏水基团与水分子总的作用面积减少,溶液中的水分子氢键网状结构变得松散,最终一些水分子会脱离氢键网状结构并以大小不等的团簇存在于溶液中,而乙醇分子的亲水基团则与其周围的自由水分子通过氢键缔合在一起。
In order to study the molecular interactions involved in dilute ethanol-water solutions, the OH stretching vibration spectra of ethanol-water solutions with the concentration range of 0-10 vol.% were measured, and the difference spectra of the samples were calculated. The hydration of ethanol molecule in the solutions of low concentration was analyzed based on the difference spectra. The result shows a very small amount of ethanol in the solution can enlarge the hydrogen bonding network in pure water, and the hydrogen bonding degree of water molecules around hydrophobic groups of ethanol molecules was also enforced. Ethanol molecules tend to aggregate together with increasing concentration, which was caused by hydrophobic hydration, and the hydrogen bonding network of water molecules become loosen due to this. As a result, some of the water molecules break away from the hydrogen bonding network, and transfer to small clusters of different size; at the same time, the hydrophilic groups

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基于氢键的超分子液晶体系的研究是一个充满活力的前沿研究领域,利用分子间氢键相互作用组装超分子液晶材料是设计新颖动态功能材料的全新途径.本文简要概述了基于C=O…N―H横向分子间氢键的棒状液晶分子的研究进展,以期为新型超分子液晶体系的分子设计提供一点借鉴.
This paper describes some progress in supramolecular liquid crystals based on C=O…N-H lateral intermolecular hydrogen bonds.

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