硼烷

The distance between atoms and plane deviation angle of the metallaborane are much longer and larger respectively than those of carborane.

金属原子的引入有效增加分子的NLO系数，同时金属硼烷的前线分子轨道能级差比碳硼烷小很多，金属硼烷材料有可能表现出半导体甚至导体特性，金属原子采用不同基组对计算结果影响不大。

The formation situation of the bond for metallocarboranes and metalloboranes is analyses with the bond valence formula for atomic cluster compound.

运用原子簇化合物键价公式，对金属碳硼烷和金属硼烷进行了成键情况分析，提出了碳硼金属三中心键和硼硼金属三中心键的概念，并指出了簇合物型、夹心型和多层夹心型金属碳硼烷的稳定存在主要是形成金属三中心键的缘故

In ChapterⅤ, the asymmetric reduction of prochiral ketones using borane as the reagent catalyzed by chiral dysprosium catalyst were described.

第五章主要研究了手性镝试剂催化下硼烷对潜手性酮的不对称还原反应，结果表明异丙氧基镝对硼烷还原酮有明显的催化作用。

Meanwhile, the isomer with a larger change of dipole moment has larger value of the first hyperpolarizability during the charge-transfer process.

5， 6， 7顶点双取代碳硼烷桥连分子受推拉电子基的影响，5， 6， 7顶点碳硼烷的构型发生一定变化，碳硼烷中两个C原子间的距离变长；同时碳硼烷中两个C原子取代位置的不同，影响了分子的稳定性和极化率，取代基团与碳硼烷中成键数较低的C原子相连的异构体，稳定性较好且具有大的极化率； 5，6，7顶点双取代碳硼烷桥连分子形成一维结构有利于分子内电荷转移，在电荷转移过程中偶极矩变化较大的体系，其二阶NLO系数也较大。

Two potential novel environmentally friendly ashless vegetable oil additives, 2-mercaptobenzothiazole derivatives, di-n-dodecyl-[2-(2-benzothiazolyl)thio]ethylborane and di-n-dodecylthio-[2-(2-benzothiazolyl)thio]ethylborane, were synthesized and their tribological performance as additives in rapeseed oil was evaluated using a four-ball wear tester.

合成了两种新型环境友好型植物油无灰添加剂，即二正十二烷氧基-2-[(2-苯并噻唑基)硫代]乙氧基甲硼烷和二正十二烷硫基-2-[(2-苯并噻唑基)硫代]乙氧基甲硼烷。

Two benzothiazole ester compounds containing boron with different alkyl chain, Di-n-hexyl-[2-(2-benzothiazolylthio)] ethyl boric acid ester (BNS-1) and Dicyclohexyl-[2-(2-benzothiazolylthio)] ethyl boric acid ester(BNS-2), were synthesized and their tribological performance as additives in rapeseed oilwas investigated using a four-ball testing machine.

合成了两种含不同烷基链的含硼苯并噻唑酯类化合物，即二正己氧基-2-[(2-苯并噻唑基)硫代]乙氧基甲硼烷(BNS-1)和二环己氧基-2-[(2-苯并噻唑基)硫代]乙氧基甲硼烷(BNS-2)。

Heterborane was gained by displacing of other non-metallic atoms to Boron of borane skeleton structure.

凡是硼烷骨架中的硼原子被其它非金属原子取代后均可得到杂硼烷。

Part Ⅰ The Research of Chiral Phosphorus Catalysts in the Enantioselective Borane Reduction of Prochiral Ketones ABSTRACT In this paper, the preparation of varied types of chiral phosphorus ligands and their applications as catalysts in the asymmetric borane reduction of prochiral ketones were investigated.

第一部分对映选择的潜手性酮的硼烷还原反应中手性磷催化剂的研究本文研究了多种不同类型的手性磷配体催化剂的合成及其在酮的不对称硼烷还原反应中的应用。

The best results 98% ee, 94% ee and 59% ee were obtained in silylcyanation of aldehydes, borane reduction of prochiral ketones and ketimines, respectively.

醛的硅氰化反应ee值最高达到98%，酮的硼烷还原反应ee值达94%，而亚胺的硼烷还原反应ee值只有59%。

The recent progress in molecular design and synthesis of polyborosilazane precurosors for SiBCN ceramics is reviewed.Especially the borazine modified polyborosilazane,monofunctional borane modified polyborosilazane on side chai...

本文分4个方面，即基于硼吖嗪的聚硼硅氮烷、侧基含有环硼氮烷或单硼烷的聚硼硅氮烷、基于多官能硼烷构筑的聚硅氮烷和含硼聚硅基碳化二亚胺，从聚硼硅氮烷分子结构设计、改性、合成及在多维尺寸材料中初步应用的角度综述了该领域国内外研究的新进展，指出了聚硼硅氮烷陶瓷前驱体设计合成研究发展中值得关注的新方向。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。