三键

The formation situation of the bond for metallocarboranes and metalloboranes is analyses with the bond valence formula for atomic cluster compound.

运用原子簇化合物键价公式，对金属碳硼烷和金属硼烷进行了成键情况分析，提出了碳硼金属三中心键和硼硼金属三中心键的概念，并指出了簇合物型、夹心型和多层夹心型金属碳硼烷的稳定存在主要是形成金属三中心键的缘故

According to the regular condensation polymerization principle, a certain amount of amino terminated polyether D230 and a certain amount of divinyl three amine are mixed uniformly by water, and then a certain amount of hexanedioic acid is added in and stirred for dissolving.

本发明属于工业水处理技术领域，具体涉及一种抑制水中二氧化硅/硅酸盐垢沉积的非离子型聚合物及其制备方法，该聚合物是一种含具有醚键、仲胺键、肽键结构的非离子型共聚物，具体为己二酸/端氨基聚醚/二乙烯三胺共聚物，按照常规的缩聚反应原理，首先用水将一定量的端氨基聚醚D230和一定量的二乙烯三胺混合均匀，然后加入一定量的己二酸并搅拌使其溶解。

The LAB series bonding agents (modificating of alcohol amine complexing with boron trifluoride),the hydantoin and triazine series bonding agent BA603 and the borate ester bonding agent BAG-5 can effectively raise the mechanical properties of the high-energy four groups HTPB propellant when complexing with MAPO,but they can not meet the require- ments of the engine use.

改性醇胺和三氟化硼的络合物LAB系列键合剂、海因三嗪类键合剂BA603与有机硼酸酯键合剂BAG-5在与MAPO复配用于高能丁羟四组元推进剂中，能有效提高推进剂力学性能，但都不能满足发动机使用要求。

Pressing the UP/DOWN key to select the contents of inner playing format, pressing the LEFT/RIGHT key to select the previous or the next page. And you can select the playing modes such as Normal, Repeat one, Repeat All by pressing the MODE key. When selecting one page, pressing the OK key, then it will start to play. During the playing, pressing MODE key to select 11 different tone such as Jazz, class, dance, heavy, disco, soft , live, hall, flat, rock, pop. Pressing REC key to make A-B recycle playing, pressing OK key to pause.

按上下选择键进行内部播放格式目录选择，按左右选择进行目录下的上一页面和下一页面的选择，在当选择的页面时，可按机体侧面的MODE键选择播放模式(如：顺序播放，单曲循环，全曲循环)三种播放模式，当选择要播放的页面时，按五方向键中的OK键，此时可进入播放状态，在播放过程中，按MODE键可进行11种音效选择(爵士乐，聚会，舞蹈，重低音，狄斯高，柔软声，活泼，大厅，平坦的，摇滚，爆劲jazz class dance heavy disco soft live hall flat rock pop)，操作REC键可进行A~B回放，按方向键中的OK键可暂停播放或播放功能。

Pressing the UP\/DOWN key to select the contents of inner playing , pressing the LEFT\/RIGHT key to select the previous or the next page. And you can select the playing modes such as Normal, Repeat one, Repeat All by pressing the MODE key. When selecting one page, pressing the OK key, then it will start to play. During the playing, pressing MODE key to select 11 different tone such as Jazz, class, dance, he**y, disco, soft , live, hall, flat, rock, pop. Pressing REC key to make A-B recycle playing, pressing OK key to pause.

按上下选择键进行内部播放格式目录选择，按左右选择进行目录下的上一页面和下一页面的选择，在当选择的页面时，可按机体侧面的MODE键选择播放模式(如：顺序播放，单曲循环，全曲循环)三种播放模式，当选择要播放的页面时，按五方向键中的OK键，此时可进入播放状态，在播放过程中，按MODE键可进行11种音效选择(爵士乐，聚会，舞蹈，重低音，狄斯高，柔软声，活泼，大厅，平坦的，摇滚，爆劲jazz class dance he**y disco soft live hall flat rock pop)，操作REC键可进行A~B回放，按方向键中的OK键可暂停播放或播放功能。

In this thesis,the AM1,MNDO,MINDO/3(mainly AM1)and INDO/S-CI semiempirical MO methods were used toinvestigate the excited-state intramolecular protontransfer reactions of salicylic acid derivatives—salicylic acid,methyl salicylate,salicylaldehyde,o-hydroxyaceto-phenone,salicylamide and 3-hydroxy-picolinamide (6 conformers and 2-3 anion species);2-(2'-hydroxy-5' methylphenyl) benzotriazole(4 conformers),2-(2' hydroxyphenyl) benzimidazole (3 conformers and 3anion species),Bis-2,5-(2-benzoxazolyl)hydroquinone(3 conformers),2-(2'-hydroxyphenyl)benzothiazole(2conformers) and 7-azaindole dimer (2 conformers).Theinvestigations were described as follows.Geometry optimization,relative stability andhydrogen bonding energy First,for sylicylic acid derivative molecules,the AM1,MNDO and MINDO/3 methods were used toinvestigate ground-state geometry optimization,energies,relative stabilities and hydrogen-bondingenergies on the five kinds of the molecules(designing 6 conformers and 2-3 anion species).Comparing with experimental data,the optimizedgeometry,the order of stability,the hydrogen-bonding energies and the distances between O-O in O-H..O hydrogen bonds by AM1 method were in agreementwith the experimental data,however,the C-C bondlengths optimized by MNDO and MINDO/3 were longer,C-O and O-H bond lengths were shorter;for C-N bondlengths,the results opitimized by MNDO method werethe same as those by AM1 method,nevertheless the C-Nbond lengths given by MINDO/3 method were muchshorter.For some sylicylic acid derivatives(e.g.methyl salicylate,salicylamide),the order ofstabilities on the conformers given by MNDO andMINDO/3 methods were not in agreement with theexisting conformers deduced by experimental methods,and the hydrogen bonding energies calculated by MNDO.and MINDO/3 methods were smaller.Second,the studyon the other systems found that the optimizedgeometry of the proton-transfered product with INDOmethod could not be obtained,only could theoptimized geometry of reactant be obtained,and thecalculated hydrogen bonding energies were greater.Many results of calculation indicated that the studyon the excited-state intramolecular proton transferreaction system using AM1 method was suitable andreliable.

本论文用AM1、MNDO、MINDO/3（主要是AM1）和INDO/S-CI半经验分子轨道方法对水杨酸衍生物系列——水杨酸、水杨酸甲酯、水杨醛、O-羟基乙酰苯酮、水杨酰胺和3-羟基吡啶酰胺（6种异构体和2-3种阴离子）；2-（2'-羟基-5'-甲基苯基）苯并三〓唑（4种异构体）；2-（2'-羟基苯基）苯并咪唑（3种异构体和3种阴离子）；2，5-二间氮杂氧茚氢醌（3种异构体）；2-（2'-羟基苯基）间〓杂硫茚（2种异构体）和7-〓吲哚二体（2种异构体）的激发态分子内质子转移反应在以下几个方面进行了较系统的理论研究：几何构型优化和相对稳定性及氢键能首先以水杨酸衍生物系列分子为例，用AM1、MNDO和MINDO/3方法考察了5种分子（每种分子设计6种异构体和2-3种阴离子）的基态几何构型优化，能量、相对稳定性和氢键能计算，通过和实验数据进行比较，AM1方法给出的优化几何构型、稳定性次序、氢键能和O—H。。。O氢键的0—0距离与实验数据吻合最好，MNDO和MINDO/3方法优化的C-C键长偏长，C-O键和O-H键长偏短；对于C-N键长，MNDO和AM1优化结果差别不大，而MINDO/3给出了过短的C-N键长，MNDO和MINDO/3方法给出的有些水杨酸衍生物分子（如水杨酸甲酯和水杨酰胺）异构体的稳定性次序和实验上推测的可存在异构体结果不一致，MNDO和MINDO/3方法给出的氢键能偏低，对其他体系的研究发现INDO方法常常不能得到质子转移产物的优化几何构型，只能得到反应物的优化构型，并且估算的氢键能偏高，大量的计算结果表明AM1方法对本论文研究的激发态分子内质子转移反应体系是适宜和可靠的。

Second, residues in the reactive site of the inhibitor were replaced by the consensus substrate recognition sequence of furin, namely, Arg at P_1, Lys at P_2, Arg at P_4 and Arg at P_6. In addition, the P_7 residue Asp was substituted with Ala to avoid possible electrostatic interference with furin inhibition. Finally, the extra N and C terminal residues beyond the doubly conjugated disulfide loops were further truncated. However, all resultant synthetic peptides were found to be temporary inhibitors of furin and kexin during a prolonged incubation, with the scissile peptide bond between P1 and P'1 cleaved to different extents by the enzymes.

高活性、低分子量的furin酶抑制剂有可能发展成为新型的抗细菌内毒素和抗病毒感染的药物，我们以绿豆胰蛋白酶抑制剂Lys片段长链22肽为模板，设计了一系列能抑制furin和kexin活性的突变体，采用如下三种方法逐步优化：一、去除Lys片段长链三对二硫键中的一对，用Ser替换Cys，减少可能存在的二硫键错误配对；二、抑制剂的活性中心根据furin底物的专一性逐步改变，即P1、P2、P4和P6位分别变为Arg、Lys、Arg和Arg，同时为了避免P7 Asp和P6 Arg之间可能存在的相互作用，将P7位Asp替换为Ala；三、将两对二硫键形成的双环的外面5个氨基酸残基去除。

But in the systems of HO-C≡P and NH2-C≡P, H-P=C=O and N≡C-PH2 containing C≡N triple bond are thermodynamically the most stable species, respectively.

而在HO-C≡P和NH2-C≡P体系中，热力学最稳定的结构却是H-P=C=O和含C≡N三键的N≡C-PH2。

Aspecial sturcture containing two one-fold atoms, two triple bond (1.95),was obtained after geometry optimization.

在模型几何优化中，得到了带有2个一配位原子的特殊结构，它含有2个三键（1.95）。

The results indicate that isomers P≡C-BH2 and CH3-C≡P containing C≡P triple bond are thermodynamically the most stable species in BH2-C≡P and CH3-C≡P systems, respectively.

结果表明，含C≡P三键的异构体BH2-C≡P和CH3-C≡P在各自的体系中分别是热力学最稳定的结构。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了