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With NMR and DFT methods, the Michael additions of alkynyl Fischer carbene complex with a series of substituted pyrazoles as nucleophiles were also studied. All reactions follow the same three-step pathway mechanism described above. Substituents on 3-, 4- and 5- positions of the pyrazolyl ring affect the reaction in the steric and electronic manners, even to change the rate-determining step.

一系列取代吡唑与1-炔基Fischer卡宾化合物的Michael加成反应都遵循前面提出的三步机理，其中吡唑的3-， 4-， 5-位分别从电子效应和立体效应方面不同程度地影响着反应的进行，甚至改变反应的决速步骤。

Substituent effect of pyrazoles was also investigated by DNMR and DFT.We successfully synthesized these intermediates with exclusively-conformations in a mild condition. X-ray results show that substituents in the pyrazolyl ring affect greatly on the structures of products, especially theπdelocation of the fragment 1-metal-butadiene.

本文以取代吡唑和1-炔基Fischer卡宾化合物的Michael加成反应合成了12个-型β-吡唑基烯基卡宾化合物，反应条件温和。X-ray晶体衍射显示吡唑上取代基对产物结构，特别是1-M-丁二烯的共轭程度具有较大的影响。

The largest chemical shifts were observed for the proton 1.48 ppm adjacent to the central pyridinium ring and para-protons 1.47 ppm with respect to the nitrogen of pyridinium.

在最终的亲核加成化合物2-F的芳香族区中的这些化学位移与9，10二氢-9-甲氧基-9-(4甲氧基苯基)-10-甲基吖啶的对应物是一致的，17b 这被证明是与过量的MeOH形成的9-苯基吖啶盐的加成化合物（支持信息中的图S7）。

The largest chemical shifts were observed for the proton 1.48 ppm adjacent to the central pyridinium ring and para-protons 1.47 ppm with respect to the nitrogen of pyridinium.

对于与中心吡啶环相邻的质子（ΔHa=1.48ppm）以及相对于吡啶的氮的对位质子（（ΔHc=1.47ppm）观察到了最大的化学位移。

The characteristic vibration modes of pyridone ring and amino group were showed with normal mode analysis, the reason for the difference between theoretical bands and experimental spectrum was discussed.

通过简正分析，指认了吡啶酮环和氨基的特征振动频率，讨论了引起计算数据与实验结果差异的主要原因。

Insulate the tube type series:Dian tube Pyrocondensation, silicone tube, yellow wax tubes, high temperature casing, waterproof cable connector, environmental conservation rubber coil, beam lines ring, beam lines Block.

三、绝缘管类系列：热缩佃管、硅胶管、黄腊管、高温套管、防水电缆接头、环保橡胶护线圈、束线环、束线座。

The results show that the aromatic structures of two six-member-ring are changed to quinonoid structure, along with the increase of polymeric chain.

在第六章中，我们通过理论计算研究了四种经典芳香环的并聚物的电子结构。

Wire dividers are located on a radially outer surface of the radial ring.

分线器位于所述径向环的径向外表面上。

Radially oriented ring magnets with high uniformity have been widely used in aviation and spaceflight.

高性能、高均匀性辐射取向环形磁体在航空、航天、航海的导航系统和控制系统中有重要的应用[1，2]。

Objective To determine the scattering and density effects of intrauterine contraceptive ring on pelvic radiotherapeutic dosage distribution.

目的 测量元宫型金属宫腔内节育环对放射治疗引起的密度效应及次级射线引起的散射效应对放射治疗剂量分布的影响。

We got alerted a couple of times while we were down south that HETs were on the way to bring us back up north because things were going to go hot again, but it was just rumors.

南下的途中我们不只一次得到警告说重型装备运输车将拉着我们重新北上，因为局势正在变得重新紧张起来，但这只是谣传。

It's the one where they find the ghost in the salt mine.

这一集是演他们在盐矿找到鬼