碳环的

The present invention relates to a coating composition comprising; A at least one polyester oligomer prepared from reactants comprising a 20 60 wt.% of at least one polyol, b 5 30 wt.% of at least one polycarboxylic acid selected from the group of cyclic polycarboxylic acids, the esters or the anhydrides thereof, wherein the carboxyl groups are separated by 3 carbon atoms or less, and from the group of alpha , beta -saturated acyclic polycarboxylic acids, the esters or the anhydrides thereof, and c 20 60 wt % of at least one monocarboxylic acid, the sum of the wt.% indicated for the reactants,, and always being 100 wt.%, and the oligomer being a low-viscosity oligomer having a weight average molecular weight Mw of less than 5,000, and a hydroxyl number in the range of about 200 to about 400 mg KOH/g oligomer, and B at least one polyisocyanate.

本发明涉及一种包含如下组分的涂料组合物：A至少一种由包含如下成分的反应物制备的聚酯低聚物：a20-60wt％至少一种多元醇，b5-30wt％至少一种选自其中羧基被3个或更少碳原子隔开的环状多元羧酸、其酯或酸酐以及选自α，β-饱和的无环多元羧酸、其酯或酸酐的多元羧酸，以及c20-60wt％至少一种一元羧酸，其中反应物、和的wt％之和总是为100wt％，所述低聚物是重均分子量Mw低于5000且羟基值为约200-约400mg KOH/g低聚物的低粘度低聚物，以及B至少一种多异氰酸酯。

The affections on the yield of DLLA caused by catalyst, temperature and time etc. were studied. By using ethylene glycol as diluent, the distillate temperature of DLLA was lowed and the carbonization phenomenon could be avoided, which caused the yield of DLLA increasing from 36.8% to 51.3%. The molecular weight of PDLLA prepared by this method could reach 184,000. DLLA and PDLLA was characterized and analyzed by DSC, XRD and IR.The key of direct method to synthesize PDLLA is the exclusion of H2O from reaction system.

丙交酯开环聚合制备PDLLA的关键在于中间体D，L-丙交酯的制备，研究了催化剂、反应温度、反应时间等因素对DLLA产率的影响，通过在反应体系中加入稀释剂乙二醇，DLLA的馏出温度明显降低，避免了DLLA在蒸馏过程中产生碳化现象，并使DLLA的平均产率由36.8％提高至51.3％，制备的PDLLA分子量最大值达18.4万。

To establish influence of chlorine and sodium on the electronic charge distribution in the molecule,we have compared experimental data forortho,m-,and p- chlorobenzoateswith those for sodium benzoate,and o-,m-,and p- chlorobenzoic acids,respectively.

从各种不同的方法中得出的结论是相同的，且表明氯和钠影响了苯甲酸的芳香体系，氯和钠的影响特征取决于氯在环上的位置，并在碳原子上计算的形式电荷和它的化学位移之间提出相关性。

Spirodilactone s are a series of compounds with the structures of spiro carbon and lactone which result in the special physical and chemical characters of Spirodilactone s.

螺双内酯是一类含双内酯环和螺碳原子这一特定结构的化合物。这种特定螺双内酯结构决定了这类化合物具有特殊的物理和化学性质。本文主要综述了螺双内酯及衍生物的合成方法、衍生化反应、手性拆分以及在合成高分子领域的研究现状和进

Therefore, in the laboratory, a 2L gasliquid equilibrium measurement device was used to measure the equilibrium solubility of H2S, CO2, CH3SH and COS in the mixed solutions of Methyldiethanolamine, Tetramethylene sulfone respectively under different temperatures and different proportions. With the relevant parameters being correlated from the measured data, a corresponding thermodynamic calculation model was set up, based on the gasliquid two phase state equilibrium equation, and in combination with the overseas research results.

为此，在实验室利用容积为2 L的气液平衡测定装置，测定了不同温度和溶液配比条件下硫化氢、二氧化碳、甲硫醇、硫氧碳在甲基二乙醇胺（Methyldiethanolamine，MDEA）、环丁砜（Tetramethylene sulfone，TMS）水溶液中的平衡溶解度，并根据气液两相平衡状态方程，结合国外研究成果，利用测定的平衡溶解度数据关联出相关参数，建立了相应的热力学计算模型，用于预测该复杂体系中酸气分压与溶液负荷的气液平衡关系。

The results showed that Kaidimycin was chemically neutral, macrocylic polylactones, stable and liable to dissolve into water and pyridine, slight to dissolve into methanol, ethanol and N-butanol, difficult to dissolve into ethyl acetate, acetone, benzene and chloroform. Chemical reaction of functional group of Kaidimycin showed that it had glycoside, amino acid and aldehyde, no reducing sugar, polypeptide and phenol.

凯地菌素属中等极性的、中性抗生素，极性纸层析结果与多烯类抗生素的纸层析结果相似：易溶于水、吡啶，微溶于甲醇、乙醇、正丁醇，不溶于乙酸乙酯、丙酮、苯、三氯化碳；对高温、光照和紫外处理有很好的稳定性；官能团反应试验结果发现，凯地菌素可能含有糖苷键、氨基酸伯氨基和醛基，不含有还原糖、多肽和酚基，高锰酸钾、浓硫酸反应与多烯大环内酯类抗生素的特性相似；并且依据纯品，采用生物法和分光光度法对摇床发酵液进行了效价的测定。

Oxazaborolidine, which derive from the coordination of amino alcohol and borane, are good catalysts for the borane reduction reaction. A kind of fused cyclic oxazaborolidine invented by Corey and derived from proline has been successfully used in the production of MK-0417 as excellent chiral catalyst by Merck company.

在该反应中氨基醇类配体原位与硼烷配位形成的手性恶唑硼烷是该反应的良好催化剂，其中Corey等发明的由脯氨酸出发制备的稠环手性催化剂性能优异，已经在Merck公司生产碳酸酐酶抑制剂MK-0417中得到成功应用。

The diagnostic vibrational modes of these complexes were predicted and assigned. Bond length, total atomic charge, frontier molecualr obital energy, molecular obital coefficience, and Mullicken Bonding Population demonstrated that electron transfer should have happened from benzene to ammonium, and therefor the charge-transfer complex should be formed.

通过复合物中的键长、原子净电荷、分子轨道能量和系数、Mullicken成键布居等量子化学参数的分析得出了铵和苯环碳原子发生作用而形成电荷转移复合物，铵和苯之间的作用包含s-π相互作用的结论。

Based on the higher-order Cauchy-Born constitutive model, a seriers of infinitesimal mechanical properties and the strain energy for the graphite sheet and SWCNT are studied firstly with the consideration of the influences from tube chirality and radius, potential parameters and the inner displacement.

基于所发展的高阶Cauchy-Born广义连续体本构模型，首先对石墨片和单壁碳纳米管的一系列无限小变形的力学特性(如：轴向和环向模量、泊松比、剪切模量)以及应变能进行了研究，同时也考察了手性、半径、势能参数以及内位移放松等因素对这些力学特性的影响。

In addition, the free group of negative ion came into being as a result of charge transfer between C=O band of vitamin M molecules and silver particles, and the C=O band was opened.

实验结果表明，VM在银表面的吸附发生在COO-基团，并且VM分子的C=O与银发生电荷转移后形成负离子自由基，碳氧双键打开，同时受VM分子吸附在银胶表面的影响，苯环结构发生了很大的扰动。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。