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The structures and properties of nine derivatives, which are formed between two or three cations and the three active sites of the most stable glycine conformer, have been probed; And the binding strength between the different active sites of glycine and different cations have been compared in BSSE method.33. The activation parameters, coupling matrix element and so forth of Fe4+Gly system have been investigated with the hereto-exchange model and calculation scheme for weak coupling system.

鉴于一个甘氨酸分子就具备三个活性位和人体中大量阳离子的存在，在上述考察了甘氨酸分子的某一活性位结合了一阳离子之后，进一步探讨了其余两个活性位再与一个甚至两个阳离子继续作用所形成的九种衍生物的结构和性质。

1H NMR spectroscopic analysis of aromatic protons combined with theoretical analysis of molecular structures proved the existence of two rotational isomers at 300 K, as well as a rapid interconversion equilibrium at 330 K for both compounds Ⅰ and Ⅱ. However, only one conformer exists for compound Ⅲ and puerarin containing 7-phenolic hydroxyl instead of propyl in A-ring as the case of compounds Ⅰ and Ⅱ. Based on UV-Visible absorption data of neutral and basic solutions, and on the density function calculations, the 7-phenolic hydroxyl group in A-ring was found to be more acidic than the 4'-phenolic hydroxyl group in B-ring. The mechanism of derivation reaction and the structure-reactivity relationship of puerarin as an antioxidant were further discussed.

其中7-丙基葛根素Ⅱ属于新型取代衍生物；变温1H NMR和理论计算结果表明，在300 K时，葛根素和4'-丙基葛根素以单一构型存在；而7，4'-二丙基葛根素和7-丙基葛根素则存在两种核磁可分辨的旋转异构体，当温度升至330 K时，两种异构体可以相互转化；通过对比分析葛根素及其衍生物脱质子产物的紫外可见吸收光谱并结合理论计算，确定了A环上7位酚羟基比B环上4'位酚羟基先脱去质子，并由此进一步阐明了葛根素衍生化反应机理以及在抗氧化作用中可能的活性位点和结构活性关系。

The influences of the inclusion of Na~+ into each conformer (C7AB, C7"AB, C7eqB, C5A, C7axB orα"B) of AD molecule on the Ramachandran angles of molecular backbone and the hydrogen bonds in AD moiety were discussed in detail. It was found that in the forming process of bidentate structures of Na~+-AD ion-complexes, the original H-bonds in AD molecule were fully broken down, accompanying with the new formation of the two Na-O bonds.

论文中详细探讨了Na~+-AD络合离子六种构象的空间构型，分析了丙氨酸二肽与Na~+作用过程中AD分子骨架Ramachandran角及分子内N(1)–H(1)…O(2)、N(2)–H(2)…O(1)、N(1)–H(1)…N(2)和N(2)–H(2)…N(1)氢键的变化，研究发现Na~+与AD分子形成双齿结构时，AD骨架中原先的氢键全部被破坏，继而形成了两个新的Na-O键；Na~+与AD分子形成单齿络合离子时，AD骨架中原先的氢键或者得到增强或者断裂之后出现新的强度更大的氢键。

In the early development of clutch structures, the most successful conical clutch.

在早期研发的离合器结构中，锥形离合器最为成功。

On the basis of static experiments, dynamic interaction tests between ice and conical structures are conducted .

在锥体静力试验的基础上，进行了冰排与锥体动力相互作用的试验。

The third chapter is mainly concerned with the physical model tests of static ice loads on conical structures.

第三章是关于模型冰排对正倒锥体结构物静力作用的物理模拟试验研究。

The rapid development of socialist construction in our country needs a great quantity of timber,particularly coniferous,which are often used in architectural structures.

随着社会主义建设的发展，需要大量木材，用于建筑结构的针叶树木材就显得更加珍贵了。

Their structures were characterized as dihydroconiferyl dihydro-p-coumarate, vanillin, apocynin, p-hydroxybenzaldehyde, syringaldehyde, syringic acid, syringylethanone,α-hydroxypropiosyringone, coniferyl aldehyde, dihydroconiferyl alcohol, 2-hydroxyphenylpropanol, and 3-hydroxy-4-methoxy-phenylethanol, respectively.

结果 从该植物中分离得到12个酚性化合物，其结构分别为二氢松柏醇二氢对羟基桂皮酸酯，香草醛，罗布麻宁，对羟基苯甲醛，丁香醛，丁香酸，丁香乙酮，α-羟基丁香丙酮，松柏醛，二氢松柏醇，2-羟基苯丙醇和3-羟基－4-甲氧基苯乙醇。

By using the swirling strength method,the vortex structures excluded the effect of shear were shown clearly,and were concentrated in the coniform area of the central mixing flow field.With increasing Reynolds number,swirling strength increased and the coniform area became narrow.

利用旋涡强度法分析流场清楚地显示出排除了剪切作用的涡结构主要集中在混合层中心的锥形区域，随着Reynolds数的增大，旋涡强度的值不断增大而锥形区域不断变窄。

Crystal structures showed that there was super conjugation in both compounds.

晶体结构表明，分子中都存在超共轭效应。

"Second Life is remarkably easy to work with, and is very popular,"

"第二次生命是显着容易的工作，并且很受欢迎，"

For example, we usually assume that materials are homogeneous and isotropic and free of internal defects or flaws.

为了得到适合有限元分析的模型，我们必须经过如图2所示的简化步骤。