triple-crown

The synthesis and properties of metal-carbyne complexes is always a hot topic in the research field of organometallic chemistry since the first synthesis of transition metal complexes with a formal metal-carbon triple bond reported by E.O.

自从1973年E.O.Fischer合成了第一个含有金属碳叁键的金属卡拜化合物以来，金属卡拜化合物的合成和反应性能一直是金属有机化学中的前沿研究领域之一。

But in the systems of HO-C≡P and NH2-C≡P, H-P=C=O and N≡C-PH2 containing C≡N triple bond are thermodynamically the most stable species, respectively.

而在HO-C≡P和NH2-C≡P体系中，热力学最稳定的结构却是H-P=C=O和含C≡N三键的N≡C-PH2。

Aspecial sturcture containing two one-fold atoms, two triple bond (1.95),was obtained after geometry optimization.

在模型几何优化中，得到了带有2个一配位原子的特殊结构，它含有2个三键（1.95）。

The facts influencing the high stereoselectivity were discussed. It is proposed that the stability of the tri- molecular transition state or the stereoelectronic effect of the vinyl anion intermediate formed by the nucleophilic addition of halide anion to the electron-deficient carbon- carbon triple bond might be responsible for the high Z-stereoselectivity.

通过对影响反应的高立体选择性因素的研究，认为反应的三分子过渡态的稳定性或生成的烯基负离子中间体的立体电子效应决定了反应的高度Z立体选择性。

The results indicate that isomers P≡C-BH2 and CH3-C≡P containing C≡P triple bond are thermodynamically the most stable species in BH2-C≡P and CH3-C≡P systems, respectively.

结果表明，含C≡P三键的异构体BH2-C≡P和CH3-C≡P在各自的体系中分别是热力学最稳定的结构。

Advances in Research on Plants Reactions under Phosphate Starvation;2. Topics discussed in this article includes synthesis and structures of R2M24, the reactions of its metal-metal triple bond with various reagents such as nucleophiles, carbon-carbon mu.

本文对一类重要的ⅥB族金属叁键化合物R_2M_2_4(R为环戊二烯基及类环戊二烯基)近年来的研究成果进行了综述，综述重点是这类化合物的官能团M≡M参键的化学活性，全文包括R_2M_2_4的合成及结构，M≡M叁键与亲核试剂、与碳-碳重键，与氧或与金属羰基物等试剂的反应及其应用。

It occurs at the carbon-carbon triple bond in a highl regioselective manner. Therefore, the reaction not only expanded the synthetic applications of Diels-Alder reaction but also provided a facile and efficient synthetic procedure for the synthesis of 4-functionalized quinoline derivatives.

上述反应实现不仅扩展了Diles-Alder反应在有机合成的应用，同时喹啉类化合物4-位上官能化的二硫缩烯酮基团也为其4-位取代打开了大门，为合成各种4-取代喹啉类化合物开辟了一个简洁高效的方法。

Topics discussed in this article includes synthesis and structures of R2M24, the reactions of its metal-metal triple bond with various reagents such as nucleophiles, carbon-carbon mu.

本文对一类重要的ⅥB族金属叁键化合物R_2M_2_4(R为环戊二烯基及类环戊二烯基)近年来的研究成果进行了综述，综述重点是这类化合物的官能团M≡M参键的化学活性，全文包括R_2M_2_4的合成及结构，M≡M叁键与亲核试剂、与碳-碳重键，与氧或与金属羰基物等试剂的反应及其应用。

The change in the spectral features of SER spectra detected at more negative potential revealed that an addition reaction occurred with the carbon-carbon triple bond of phenylacetylene.

电化学现场光谱研究表明，苯乙炔分子随电位负移，碳碳叁键被加氢还原。

8Fluorinated carbon-carbon triple bond formation.

8含氟碳-碳叁键的合成方法学。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。