烯

The auxiliary can be recovered in high yield (81%) only by filtering and recrystallization. Besides, some other aldehydes have been chosen to test the enantioselectivity of N,N\'-dibenzyl tartamide, in comparison with two other allylaborates reagents developed previously by Roush and Brown, respectively. The results show that %e.e. of homoallylic alcohol is superior to that of the former, and approaches the Brown reagent.

产物经S_N2反应得瑞格列萘中间体-甲基烯丙基-2-氯苯基-叠氮甲烷(17)；同时，将筛选出的新型手性配体N-苄基酒石酸二酰胺用于其他几种醛(正丁醛，异戊醛和环己醛)的不对称烯丙基化反应，并与广泛应用的Roush配体(22)和Brown配体(27)相比较，发现其立体选择性优于Roush配体，并接近Brown配体，但明显具有可回收利用的优势。

The thesis aims at the studies on the synthesis of dihydroagarofuransesquiterpenes and the synthesis of the important intermediates —α-methoxylmethyl butenolide and α-methoxyl-methyl butadienolide in the synthetic approachto Germacranolide sesquiterpenes from α--Santonin.Ⅰ.

本论文以α--山道年为原料，对二氢沉香呋喃倍半萜的合成以及吉马型倍半萜合成中的重要中间体12-甲氧基-7(11)-烯-6，13-内酯及12-甲氧基-5(6)，7(11)-二烯-6，13-内酯的合成进行了研究。

The crude toxin of scabby wheat contained deoxynivalanol 11100 ppm and zearalenonel 605 ppm.

赤霉病麦粗毒素为赤霉病麦的乙醇提取物，其中脱氧雪腐镰刀菌烯醇和玉米赤霉烯酮含量分别为11100 ppm和605ppm。

The obtained activation barrier of β-scission of 1-butene is 217 kJmol^(-1) in the reverse reaction of ethene dimerization.

反应的逆过程也就是1-丁烯在酸性分子筛表面的1-丁基烷氧化合物发生B分裂反应，计算所得相应的l-丁烯B分裂反应的能垒为217kJmol^(-1)，远高于相应的乙烯二聚反应能垒。

In Chapter 4,the site-symmetry projector is constructed to produce thecomplete symmetry-adapted orbitals.Based on this,we deduce the energy equationcontaining all the interactions of〓orbitals,the H〓ckel model secular equation,andthe energy expression containing the second neighbor hopping.Also we discuss theeffect of the second neighbor hopping on the electronic structures and properties offullerenes.

第四章阐述与位置对称性有关的投影算子的构造及其在处理富勒烯的π电子结构中的应用，导出了π轨道的所有相互作用都包括在内的能量本征方程，一极近似下的久期方程，和二级近似（考虑π轨道的次邻接相互作用）下的能量表达式，并且一般性地讨论了次邻接相互作用在富勒烯的电子结构和性质中的作用。

The conversion of cyclyopentadiene reached 100%, and the selectivity to cyclyopentadiene was over 99%.

结果表明环戊二烯的转化率可达到100％，环戊烯的选择性和收率都达到99％以上。

Chromium species in organic chromium catalyst is determined with plasma emission spectrography.

已酸铬是乙烯齐聚合成1-己烯的主催化剂，通过它与助催化剂的络合反应可以高选择性地合成1-己烯。

The experiment shows:The salt content has comparatively considerable influence on spoliation of growth of thrastochytrium proliferum and output of squalene.The mass of thrastochytrium proliferum growing in control culture media outweighs mass of thrastochytrium proliferum growing in the other two culture medias and its squalene content is much higher.

实验结果表明：盐含量对破囊壶菌的生长和鲨烯产量有比较大的影响，其中在对照培养基上生长的破囊壶菌中质量大于在其他两种培养基上生长的菌种量，鲨烯含量大于其他培养基。

ASQS is 70%, 77%, 44% and 39% identical to squalene synthases from arabidopsis thaliana, tobacco, human and yeast, respectively.

青蒿鲨烯合酶氨基酸序列与拟南芥、烟草、人类、酵母鲨烯合酶的一致性分别为70％、77％、44％、39％。

The State's attorney general filed suit under Proposition 65 against some of the biggest food companies, including McDonald's, Burger King, KFC, and Frito-Lay, to force them to put warning labels on all French fries and potato chips sold in California because they contain high levels of acrylamide, a known carcinogen.

有致癌物，主要是丙烯酰胺加州首席检察官起诉一些大食品公司包括：麦当劳、Burger King，肯德鸡，和 Frito-Lay，强制要求它们在加州销售的法式油炸和土豆片上贴上警告语：本品含有高浓度丙烯酰胺----一种已知致癌物！

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。