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The invention discloses a process for preparing N-Boc derivative or N-Cbz derivative of chiral alpha, alpha'-double substituent pyrrolidine which contains ethylenic link and acetylenic link substituent.

本发明公开了一种制备含烯键和炔键取代基的手性α，α'-二取代吡咯烷的N-Boc衍生物或N-Cbz衍生物的方法。

Using N, N-dimethyl-ethylenediamine as cationic substitute and 2-hydroxyethyl methacrylate or allylamine as co-substitute, a kind of pH-sensitive polyorganophosphazenes bearing unsaturated side group was prepared.

以N，N-二甲基乙二胺为阳离子型取代基，甲基丙烯酸羟乙酯或烯丙胺为共取代基，制备了同时带有pH响应性侧基和不饱和双键侧基的聚膦腈。

N Lorenzo Bini Smaghi, executive board member of the European Central Bank, said last week that "for the continued sustained growth of the world economy, a slowdown of Asian economies would be as worrisome, if not more, than that of the US.

n \n \n欧洲央行执委会委员洛伦佐？比尼？斯马吉上周表示：就世界经济保持当前的增长势头而言，亚洲经济体的增长放缓，将至少与美国经济放缓同样令人担忧。

The metal ions of the dinuclear copper complex of [Cu_2_2Cl_4] are linked by two N~1,N~2 1,2,4-triazole bridges,and the central Cu ions have distorted trigonal bipyramid geometries. The central Cu ion of [CuL22]·H2O has a centrosymmetric and distorted tetragonal-octahedral geometry. The metal ions of the dinuclear manganese complex of [Mn_2L_2_2Cl_2(H_2O)_2] are bridged by two chlorine atoms, and the central Mn ions have distorted tetragonal-octahedral geometries. Part III.

配合物[Cu_2_2Cl_4]是通过配体L的1，2，4-三唑环上两个氮原子(N~1，N~2)桥联形成的双桥双核配合物，每个中心铜离子都具有畸变的三角双锥构型；配合物[CuL22]·H_2O的中心铜离子具有中心对称的畸变八面体构型；配合物[Mn2L2_2Cl_2(H_2O)2]是通过两个氯原子桥联形成的双桥双核配合物，每个中心锰离子都具有畸变的八面体构型。

Given the current complexity of industrial recovery of 3'-methyl-2'-butenyl 3, 3-dimethyl-pentenoate and the decomposition problems with 2-methyl-1-butene, research was conducted on a process for direct recycling of MBDP involving an ester exchange reaction of MBDP with either methanol, trimethyl orthoacetate, or solutions of methanol and trimethyl orthoacetate.

针对目前工业上回收3，3-二甲基－4-戊烯酸－3'-甲基－2'-丁烯酯工艺复杂、异戊烯大量分解问题，研究了MBDP直接返回循环使用工艺，MBDP与甲醇、原乙酸三甲酯或与甲醇原乙酸三甲酯混合溶液进行酯交换反应的回收新工艺，比较了四异丙基钛酸酯、甲醇钠、氢氧化钾用作酯交换催化剂的效果，筛选出回收MBDP&一锅煮&最佳工艺：按照n：n：n：n＝1.0：9.8：9.2：0.05物质的量比投料，74℃~78℃反应21h，MBDP转化为贲亭酸甲酯和异戊烯醇，单程转化率87.7%，用85%的磷酸中和甲醇钠，蒸出甲醇，直接用于合成贲亭酸甲酯。

A homogeneous redox initiator system with ceric ammonium nitratein N,N-dimethyl-formamidewas reported in this paper.

研究了均相氧化还原体系硝酸铈铵/N，N-二甲基甲酰胺在无外加还原剂的条件下，引发丙烯酸甲酯，苯乙烯和甲基丙烯酸甲酯等烯类单体的聚合。

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。

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。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐