查询词典 monometallic

It was found that the samples PVP-PdCl2-CdCl2 and PVP-PdCl2-HgCl2, compared with PVP-PdCl2, exhibited much higher catalytic activity and dechlorination selectivity, and the yields of the coupling by-products were obviously decreased. For example, when p-chloroaniline was used as substrate, the reaction time was shortened to 1/8, and the yield of dechlorination product was about 25 times as much as the original one, and when p-chlorotoluene was used as substrate, the yield of coupling by-product catalyzed by bimetallic catalyst was 1/390 of that catalyzed by monometallic catalyst.

与负载型单金属催化剂PVP-PdCl2相比， PVP-PdCl2-CdCl2和PVP-PdCl2-HgCl2对氯代芳烃脱氯有高得多的催化活性和脱氯选择性，且偶联副产物显著减少；以对氯苯胺为底物时，双金属催化下的反应时间缩短为单金属催化下的1/8，而脱氯产物收率提高25倍；底物为对氯甲苯时，双金属催化下的偶联副产物仅为单金属催化下的1/390。

The alloy catalyst shows good stability for CO_2 reforming of CH4 during whole test period. The catalytic performance for Ni/Sn alloy is similar to the monometallic Ni .The formation of graphitic carbon was not observed.

在CH4的CO_2重整实验中，在800℃，CH4/CO_2=50：50时，Sn含量为1wt%的Ni/Sn合金催化剂稳定运行48小时无积碳产生，其催化活性与纯金属Ni相似。

However, the formation of metal chelation at one or two side of biphenyl resulted a pair of enantiomers of monometallic or bimetallic complexes. Moreover, if the coordinating groups have chiral element (e.g., chiral oxazolines), the diastereomeric metal complexes will be formed.

而且，如果配位基团上带有手性元素，它们跟金属配位后得到一对非对映异构体，由于手性元素的影响，形成这一对非对映异构体的能量是有差异的。

The tetraoxazoline ligands only afforded the-configuration whether monometallic and/or bimetallic palladium complexes were formed upon the complexing process. Using the chelation-induced axially chiral palladium complex as a catalyst, excellent catalytic activities and enantioselectivities in the Wacker- type cyclization of allylphenols with up to 99% ee were gained.

当它与钯离子配位后只得到了轴构型为S的单金属或双金属配合物，并将该配体应用于钯催化的邻烯丙基苯酚的Wacker-type环化反应中，获得了很好催化活性和高达99% ee。

Complex V shows a one-dimensional 'Z' chain which are linked into two-dimensional lamellar structures by weak π-π stackings. Complex VI shows one-dimensional chiral helical chains which are linked into molecular zipper. Both complexes show strong blue photoluminescent under R.T. Complexes VII and VIII are monometallic complexes of Fe.

由对苯二甲酸形成的化合物Ⅴ是由一维的'Z'型链组成的，链链之间通过π-π弱相互作用形成了二维结构；而由间苯二甲酸形成的化合物Ⅵ是由一维的手性螺旋链组成的，链链之间通过π-π相互作用形成拉链状的二维结构，Ⅴ和Ⅵ在室温下具有强荧光。

The research results show for low Sn concentrations, for example 1wt%Sn with respect to Ni, the Ni/Sn surface alloy is energetically preferred. We have also used XPS to characterize the catalysts. The quantified Sn and Ni XP spectra for Ni/Sn/SLT catalysts show that Sn preferentially segregates to the surface of the Ni/Sn alloy. We demonstrate that supported Ni/Sn alloy catalyst provides significantly higher reforming reactivity and resistance to deactivation via carbon deposition than supported monometallic Ni catalyst both in steam reforming of CH4 and CO_2 dry reforming.

本文以SLT为支撑体，利用Sn对传统的Ni基催化剂进行表面合金化处理，成功制备了Ni/Sn表面合金重整催化剂，将该催化剂用于甲烷和丙烷的CO_2重整和水蒸汽重整反应，研究结果表明，在Sn浓度很低的情况下，例如1wt%Sn含量，从能量角度看更易于形成表面合金，XPS数据也显示Sn更易于富集在Ni/Sn合金催化剂表面。

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。