顺式

Organozinc reagents can react with a variety of α,β-acetylenic ketones and aldehydes in the absence of any catalyst. The one-pot reaction affords β-branched Baylis-Hillman type adducts, the multifunctionalized alkenes, in excellent yields with high stereoselectivity.

这种顺式亲核加成反应的发生是由于该类有机锌试剂既具有较强的亲核性，又具有Lewis酸的特性，使有机锌中R基团从同位进攻中心碳原子而形成新的碳碳键。

The work reported in Part 1 started with improving the synthesis of the chiral auxiliaries and Bu〓B, two important reagents needed for performing classic Evans asymmetric aldolization.

在第二部分工作中，完成了Aerangis Lactone等含有顺式双取代内酯环的天然产物的合成。

To explore how gene products, required for the initiation of synaptic growth, move from the cell body of the sensory neuron to its presynaptic terminals, and from the cell body of the motor neuron to its postsynaptic dendritic spines, we have investigated the anterograde transport machinery in both the sensory and motor neurons of the gill-withdrawal reflex of Aplysia.

为了探索突触形成起始阶段所需的基因表达产物，由感知神经细胞体向脊柱终端，以及由驱动神经细胞体向联会后枝状脊柱的移动，研究人员对与海蜗牛腮回退反射有关的，感知和驱动神经的顺式传递装置。

It isconfirmed by ~1H NMR,~(13)C NMR and X-ray crystallographic analysis that complexes 60-63are monopyridine complexes and show distorted square pyramid geometries; complexes 64and 65 are bispyridine complexes and show pseudo-octahedral geometries, where twopyridine ligands are in cis arrangement and trans to the NHC and the benzylidene ligandrespectively, the bond length between ruthenium and pyridine ligand trans to the benzylideneligand is 16 pm longer than the bond length between ruthenium and pyridine ligand trans tothe NHC ligand.

1H NMR、~(13)C NMR及X射线单晶衍射分析证明，配合物60-63是单吡啶衍生物配位的钌卡宾配合物，具有变形的四方锥构型；配合物64、65为双吡啶衍生物配位的钌卡宾配合物，具有变形的八面体构型，其中两个顺式配位的吡啶衍生物分别处于氮杂环卡宾和苯亚甲基的反位，处于苯亚甲基反位的吡啶衍生物对应的钌-氮键长要比处于氮杂环卡宾反位的长出16 pm。

The Xray diffraction analysis of the compounds (3) and (4) shows the presence of an intramolecular coordination of oxygen to the tin atom giving rise to a fivemembered ring in which the metal exhibits a distorted trigonal bipyramidal geometry.

并通过X-射线衍射测定了（3）和（4）的晶体结构，其空间群均为P2〓/c，晶胞内分子数Z=4，分子结构是以锡原子为中心金属原子、含分子内O→Sn配位键五员环的扭曲三角双锥结构，碳碳双键的两个氢是顺式构型。

In this dissertation, I will represent my studies on the nitration of Chalcone derivatives, reaction of epoxide ketone, and the aromatization of 3,5-disubstitued 2-isoxazolines with nitric oxide.

本文主要研究了：(1)NO与查尔酮及其衍生物的硝化反应，反应以较高的产率得到了a-硝基化合物；(2)NO对环氧酮的开环反应，反应生成了顺式羟基硝酸酯；(3)3，5-二取代的-2-异恶唑啉在NO作用下可以发生芳环化反应，生成了对应的2-异恶唑化合物。

Butadiene was polymerized to some extent in the presence of binary catalyst system NdCl33iPrOHAlEt3 in toluene and the allylchloride was then added to the solution in order to cyclize the formed polybutadiene and cyclopolymerize the unreacted butadiene monomers.

采用NdCl3·3i－PrOH－AlEt3稀土催化剂进行丁二烯的顺式聚合，在聚合过程中引入烯丙基氯，进行分子内环化反应以及单体的环聚反应。

Butadiene was polymerized to some extent in the presence of binary catalyst system NdCl33iPrOHAlEt3 in toluene and the allylchloride was then added to the solution in order to cyclize the formed polybutadiene and cyclopolymerize the unreacted butadiene monomers.

采用NdCl3·3i－PrOH－AlEt3稀土催化剂进行丁二烯的顺式聚合，在聚合过程中引入烯丙基氯，进行分子内环化反应以及单体的环聚反应。考察了稀土催化剂用量、n／n（AlEt3）、环化时间、反应温度、单体浓度等对环化反应的影响，并对产物进行了红外光谱、核磁共振光谱的表

OH radicals produced by ultrasound in aqueous solution attack phenolic cycle at adjacent or para position of the hydroxyl on phenol so that phenol is changed into small organic molecules such as muconic acid, maleic acid and ethane diacid. These small organic molecules will be oxidized to form carbon dioxide and water by.

苯酚超声降解的作用机理是，超声空化在水溶液中产生的·OH自由基进攻苯酚苯环上羟基的邻位或对位而使苯环断裂生成己二烯酸、顺式丁烯二酸和乙二酸小分子有机物而使苯酚得以降解，这些小分子有机物在·OH自由基的进一步作用下最终被氧化成CO〓和H〓O。

The analyses indicated that the upstream sequence contained several regulatory elements,such as CCAAT-binding factor,GC-box,HSE and GATA,but TATA-box and CAAT-box were not be found.

分析表明，该上游序列的转录起始位点位于第3255位G碱基处，没有明显的TATA-box和CAAT-box，但含有CCAAT-binding factor、GC-box等重要的转录因子结合位点，以及热激应答元件HSE和GATA元件等启动子顺式调控元件。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。