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Using pyridine-2, 6-dicarboxylic acid as starting material, a novel ligand N^2, N^6-bis(3-methyl-pyridine-2-yl)-pyridine-2, 6-dicarboxamide was synthesized, which contained multidentate and large conjugative system.

以吡啶－2，6-二甲酸为原料，合成含有多个共轭体系多齿配体N^2，N^6-二（3-甲基吡啶）－2-取代吡啶－2，6-二甲酰胺；同时制备它与稀土离子Tb和Eu的配合物，并培养出单晶。

Attributed to the lubricant-effect of flexible LCPB,cold crystallization was observed in stereoblock PB.Bd-Ip block copolymersHTPB-b-PI,C-(PI-b-HTPBn,C-n,and PI-b-HTPB -b-PI and Bd-St block copolymersHTPB-b-PS,C-(PS-b-HTPBn,C-n, and PS-b-HTPB-b-PS containing crystallizable HTPB were well synthesized,the microstructures and properties of the copolymers were investigated in detail.

通过与异戊二烯或者苯乙烯共聚，合成了含高反式聚丁二烯的丁二烯-异戊二烯嵌段共聚物包括HTPB-b-PI，C-(PI-b-HTPBn，C-n和PI-b-HTPB-b-PI和丁二烯-苯乙烯嵌段共聚物包括HTPB-b-PS，C-(PS-b-HTPBn，C-n和PS-b-HTPB-b-PS，对嵌段共聚物的结构和性能进行了系统的研究。

Attributed to the lubricant-effect of flexible LCPB,cold crystallization was observed in stereoblock PB.Bd-Ip block copolymersHTPB-b-PI,C-(PI-b-HTPBn,C-n,and PI-b-HTPB -b-PI and Bd-St block copolymersHTPB-b-PS,C-(PS-b-HTPBn,C-n, and PS-b-HTPB-b-PS containing crystallizable HTPB were well synthesized,the microstructures and properties of the copolymers were investigated in detail.

加热器通过与异戊二烯或者苯乙烯共聚，合成了含高反式聚丁二烯的丁二烯-异戊二烯嵌段共聚物包括HTPB-b-PI，C-(PI-b-HTPBn，C-n和PI-b-HTPB-b-PI和丁二烯-苯乙烯嵌段共聚物包括HTPB-b-PS，C-(PS-b-HTPBn，C-n和PS-b-HTPB-b-PS，对嵌段共聚物的结构和性能进行了系统的研究。

In spite of this, the preparation of thiol-end functionalized PMMA was achieved by introducing a short block of polystyrene after the RAFT polymerization of MMA.Third, RAFT technique was applied to design and synthesize some well-defined poymers. Five monomers, lauryl methacrylate,(N,N-dimethylamino)ethyl methacrylate, poly methyl ether methacrylate, 4-(4\'-cyanobiphenyl-4-yloxy) butyl methacrylate and 2-ethyl methacrylate were chosen to RAFT homopolymerization or copolymerizations mediated by cumyl dithiobenzoate.

RAFT方法在具有特定结构聚合物的设计与合成上的应用，在机理研究的基础上，本论文选择五种不同结构的甲基丙烯酸酯类单体：lauryl methacrylate，(N，N-dimethylamino)ethyl methacrylate，polymethyl ether methacrylate，4-(4'-cyanobiphenyl-4-yloxy)butyl methacrylate和2-ethyl methacrylate，用CDB调控RAFT聚合的方法设计合成了一些特定结构的聚合物，详细而深入地研究了它们的均聚、共聚动力学，发现了双硫酯并非在聚合反应初期就全部转化，而是随着反应进行逐步消耗，这与理想的活性聚合体系有很大差别。

To establish a method for determination of cyclopentadiene,dimethylformamide and N-methylpyrrolidone simultaneously in isoprene by GC.

用毛细色谱法建立异戊二烯中各组分定性分析方法及环戊二烯，N-甲基吡咯烷酮，N，N-二甲基甲酰胺的测定方法。

In the second part of the thesis, we discussed a L-proline-catalyzed direct Aldol reaction between L-amino acid-derived N,N-dibenzyl -amino aldehydes 15 and acetone, cyclopentanone or hydroxyacetone, which afforded (-amino--hydroxy- or (-amino-,(-dihydroxy-ketones in good to excellent yields (up to 94%) and diastereoseletivities (up to 94.9%).

发现许多情况下，反应的产率和de值超过90%。接着，在碱性条件下，我们将L-亮氨酸衍生的N，N-二苄基--氨基醛15g与羟基丙酮反应得到的主要产物(，-二羟基-γ-氨基酮171d与次溴酸钠反应，得到了具有抗肿瘤活性的天然产物PM-94128的氨基酸片断184。

Synthesis of Antidote of N-Dichloroacetyl-2-methyl-1-oxa-4-aza-spiro-4.4-nonane BI Hong-mei, ZHANG Jin-yan, LIANG Ying, SHEN Yong (College of Arts and Sciences Heilongjiang August First Reclamation University, Daqing 163319, Heilongjiang, China) Abstract: N-Dichloroacetyl-2-methyl-1-oxa-4-aza-spiro-4.4-nonane was synthesized by one pot method with isopropanolamine, cyclopentanone and dichloroacetyl chloride. The optimum reaction conditions obtained are as follows:the proportion in moles of the above materials is 1∶1∶1.2, reaction solvent is toluene, reaction temperature is -15 to -10 ℃,reaction time is 3 h, under the optimum condition, the yield of the compound is 50.0%.

除草剂解毒剂N-二氯乙酰基-2-甲基-1-氧杂-4-氮杂-螺[4.4]壬烷的合成毕洪梅，张金艳，梁英，沈勇(黑龙江八一农垦大学文理学院，黑龙江大庆 163319)摘要：以33%的氢氧化钠水溶液为缚酸剂，异丙醇胺、环戊酮和二氯乙酰氯为原料，采用&一锅法&合成了N-二氯乙酰基-2-甲基-1-氧杂-4-氮杂-螺[4.4]壬烷，采用正交实验法得到最佳反应条件：反应原料摩尔比为1∶1∶1.2，苯作溶剂，反应的温度为-15 ℃~-10 ℃，搅拌时间为3 h，产率达到50.0%。

Firstly, dicyclopentyldichlorosilane, a reaction intermediate, was prepared under the optimal conditions of a reaction pressure range of 1.0-1.2 MPa, a n/n of 1.16, a reaction temperature range of 85-95℃, a catalyst dosage of 1.2 g, an isooctyl alcohol dosage of 2.3 g and a reaction time range of 6-7 h. The conversion of cyclopentene and the yield of DCPDCS were 96.2% and 88.9%, respectively.

首先研究了合成DCPDCS的最佳工艺条件：反应压力1.0~1.2 MPa，n/n= 1.16/1.00，反应温度85~95 C，催化剂用量1.2 g，异辛醇用量2.3 g，反应时间6~7 h，环戊烯转化率可达96%以上，DCPDCS收率可达88%以上。

After SBF solution cultivation for some days, the Ca/P coating was very easily deposited on the porous surface that was constituted of cystiform polygon made up with irregular nanometer circles like honeycomb. The energy spectrum showed that n/n atom ratio is about 1.61:1 which is very similar to that of HA and human bone. The active surface of the porous titanium after acid-alkali treatment and SBF solution condition which calcium-phosphorus ions was supersaturated induced the formation of Ca/P deposition layer.

SBF溶液培养后发现沉积层由蜂巢状多边形胞状物组成，这些胞状物是由网状纳米环无规则排列构成，能谱测定钙、磷元素原子比n／n约为1.61∶1，与HA和人骨中的钙磷原子比很接近；通过对沉积机理的分析，认为微孔钛的活性表面和SBF溶液过饱和离子浓度的环境造成了液相中钙磷盐的沉积。

First,the determinant is regarded as a function of or- der n and denoted by D;Second,the determinant is expanded by row or by column,then the relation in both of Dand subdeterminants will be examined in details to set up certain a recursion,generally speaking,it must be a homogenous or a non homogenous recursion;fi- nally the coefficients of the general solution are found out with the aid.

给出了用递归关系方法求任意 n 阶行列式的值的一般方法：首先，把已知的 n 阶行列式看作为阶数 n 的一个函数，记为 D；其次，按行或按列展开这个行列式，并仔细观察存在于余子式及 D里的关系，建立关于 D的某一递归关系，此关系总为一个齐次的或非齐次的递归关系；最后，借助于 D(0)、D(1)和D(2)等求出递归关系的通解的系数。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷