螺旋键

Herein, a self-assembly system with polymer pattern of lower molecular weight polyaerylie acid have been built up, in which some nanosized complex was synthesized, including nanosphere of Pb-PAA, one-dimensional nanorod of CuS-PAA and PbS-PAA, one-dimensional helix nanochain of PbSO4-PAA, and one-dimensional reticulate nanofibres of PbCr2O7-PAA. The mechanism was discussed preliminarily, the important action of the bone angle torsion as well as the ""contact bridge"" served by ion in the course of self-assembly was proposed for the first time.

本文以低分子量聚丙烯酸为高分子模板构建自组装体系，首先合成了几种特殊形态的纳米配合物，包括纳米微球Pb-PAA、一维纳米棒CuS-PAA和PbS-PAA、一维螺旋纳米链PbSO_4-PAA及一维有序纳米纤维网络PbCr_2O_7-PAA，初步讨论了该自组装体系的合成机理，首次提出了键角张力和分子的"搭桥"作用在自组装过程中的作用。

The influence of atmosphere on the thermal degradation behavior and thermal degradation activation energy of untanned collagen fibers are discussed.

皮革收缩行为的实质是在热的作用下，氢键作用被削弱，三股螺旋结构发生破坏，肽链分子发生横向摇摆所致。

All the compounds are characterized by IR and elemental analysis.we design and prepare a bipyridinium supramolecular compound and six coordination compounds, which are also characterized by IR, elemental analysis and X-ray structure analysis. According to X-ray structure analysis, hydrogen bonds and n-n stocking interactions participate in the architecture of three-dimensional framework [H2L1 (NO3)2 (H2O)2]n; one-dimensional zigzag coordination polymer [Hgl21.5CH3OH]n; binuclear metallamacrocycle (HgI2L2)2 3H2O; helical double-stranded one-dimensional coordination polymer [Co2(L2)2-2CH3OH]n; double-stranded one-dimensional coordination polymer [Co2(L3)2-CH3OH-CH3CN]n; and three-dimensional compound [Cu(C5H4NCOO)2(H2O)2]-H2O with hydrogen bonds, three-dimensional coordination polymer {[Cd(C5H6NCOO)2H2O]-DMF}n, which are indirectly obtained from the precursor ligand L3 through metal ion induced the hydrolysis of diamide and self-assembled with the hydrolyzate.

我们首次合成了一个双吡啶鎓超分子化合物和六个过渡金属配合物，并通过IR谱，元素分析和X-ray晶体衍射分析对它们进行了表征。X-ray晶体结构分析表明：超分子化合物[H_2L1·(NO_3)_2·(H_2O)_2]_n是由多种氢键和芳香环间的π-π堆积作用构建的三维无限结构；[HgI_2(L1)·1.5CH_3OH]_n是一维锯齿状配位聚合物；(HgI_2L2)_2·3H_2O是双核金属大环化合物；[Co_2(L2)_2·2CH_3OH]_n是具有一维双螺旋结构的配位聚合物；[Co_2(L3)_2·CH_3OH·CH_3CN]_n为一维双链结构的配位聚合物；以及由非直线形配体L3在金属离子Cu和Cd的诱导作用下发生水解，并且金属离子与水解产物——异烟酸根离子自组装，形成了三维氢键超分子化合物[Cu(C_5H_4NCOO)_2(H_2O)_2]·H_2O和三维配位聚合物{[Cd(C_5H_6NCOO)_2H_2O]·DMF}_n。

But this molecular model shows how some proteins form loops in DNA when they chemically attach, or bind, at separate sites to the double-helical molecule that carries life's genetic blueprint.

就像槲寄生包绕在柔软的甘蔗蔓藤上，分子模型展示了某些蛋白在DNA 如何形成环状，当它们用化学键贴或者绑在携带生命遗传蓝图的双螺旋DNA分子。

Reagents and so on temperature, organic solvent, potential of hydrogen, urea, amide may cause the DNA member to denaturate, even if hydrogen bond break between the DNA duplet bond's, the double helix structure unties.

温度、有机溶剂、酸碱度、尿素、酰胺等试剂都可以引起DNA分子变性，即使得DNA双键间的氢键断裂，双螺旋结构解开。

At the present time, It is a major method of research on the thermostability of thermozymes to compare the homology of amino acid sequence between thermozymes and mesophilic enzymes.

螺旋的稳定性使嗜热酶在二级结构上更稳定。在高级结构中，&额外&的离子键、疏水作用、氢键、寡聚体的形成等对嗜热酶的耐热性起主要作用。

And a'hierarchical self-assembly'model, including the wrapping of amylose chains around SWNT and the hierarchical self-assembly of wrapped-SWNTs into the superstructural A/S-C, was put forward to explain the formation process of the helical A/S-C.

在此基础上对A/S-C螺旋结构的形成机理进行了探索性研究，并提出了&逐级自组装&模型：直链淀粉分子链首先缠绕到SWNT表面，缠有直链淀粉的SWNT在氢键作用力的驱动下逐级自组装成超分子结构A/S-C。

The deletion of [A7-B7] disulfide bond in proinsulin resulted in a significant decrease of α-helix content of the molecule and a great increase in sensitivity to tryptic digestion.

结果表明，A7 B7二硫键缺失可导致胰岛素原α螺旋明显减少以及对胰蛋白酶的酶切敏感性显著增加，其对胰岛素原结构的影响主要导致了受体结合活性的大幅度降低。

This paper analyze the principle of the joggling in the cold rolling process for involute spline manufacturing and establishes the CAD model of the roller based on the principle of equal pitch helicoids.

本文通过对渐开线花键滚轧时啮合原理的分析，按照等升距螺旋面的形成理论建立了滚轧轮廓形设计模型。

Modal analysis on engine block combination structure of a piston engine;2. Research and Optimized Desegn The Structure of The 492QBZL Diesel Engine Block;3. Study on coupling dynamics of compressor crankshaft block

在表格中单击右键，然后在子菜单中不选Show Prefered Only可以显示所有的加工参数，如落刀点的设置，螺旋下刀的角度等。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。