For the nullity of graphs research has wider range, such as the research of trees, the unicyclic graphs, the bicyclic graphs and the linear graphs.

2-Substituted benzothiazoles are a class of bicyclic compounds with medicinal value. Several methods for green synthesis of these compounds are discussed.

2-取代苯并噻唑是一类具有药物活性的双环化合物。本论文主要探讨该类化合物的几种绿色合成方法。

Compared with straight chain phosphites, caged bicyclic phosphites have great differences in nucleophilic reactions due to the tension and high steric hindrance caused by the caged bicyclic structure.

双环笼状亚磷酸酯类衍生物由于其笼状结构所引起的张力及高位阻性，使得它同一般直链亚磷酸酯类化合物相比，在亲核取代反应性等方面有着明显的不同。

In this paper, inverse degree of unicyclic graphs and bicyclic graphs is discussed, and the extremal graphs that reach the upper and lower bounds are given.

研究了单圈图、双圈图的反比度，给出了它们的上下界并得到达到最大最小值的极图，还进一步给出多圈图的上下界的一个猜想。

Methods: Chloroform being solvent, under bath heat, 4 hydroxymethyl caged bicyclic phosphate acylated with pentanoyl chloride and hexanoyl chloride dividedly.

方法：用氯仿作溶剂，在浴温条件下，4羟甲基笼状双环磷酸酯分别与戊酰氯、己酰氯发生酰化反应。

Studies on asymmetric synthesis of steroids ⅱ. enantioselective reduction of some racemic bicyclic compounds by microbial catalysis

甾体不对称合成的研究11.若干消旋双环化合物微生物催化对映选择性还原

Synthesis of Bicyclic 4H-1,2-Oxazine Derivatives

取代双环4H-1,2-恶嗪衍生物的合成

Synthesis of Chiral Chloromethyl Bicyclic Phosphoramides

手性氯甲基二环膦酰胺的合成

So, naturally the next problem is to characterize the bicyclic graph with maximal Estrada index.

下一个自然的问题就是，讨论双圈图的极大Estrada指数。

Fixation with bicyclic steel wires for comminuted fracture of patella Ring Shaped Oscillator

双环形钢丝环绕固定治疗髌骨粉碎性骨折

On structure of eigenvectors of bicyclic mixed graphs

双圈混合图特征向量的结构

Stomatal apparatuses were oval, guard cells have polar layer structure. The type of stomatal apparatuses was bicyclic.

气孔器椭圆形，保卫细胞具极层结构，气孔器类型为双环型。

On the spectral radius of bicyclic graphs of order n

n阶双圈图的邻接谱半径

Bicyclic Graphs with Extremal Kirchhoff Index; 2-wire, 2-way repeater. One or two line can be specified.

双圈图的Kirchhoff指标极值两线双向中继器。可指定单线或双线。

Aim To develop a concise method for the synthesis of bicyclic azasugar and thiosugar with novel scaffold.

目的发展一种简洁合成具有新型骨架的双环氮杂糖和硫杂糖的新方法。

Synthesis of Methyl Ether of Caged Bicyclic Phosphate

笼状双环磷酸酯甲基醚的合成

Bicyclic amidine-new curing agent for epoxy resin

一种新的环氧树脂固化剂&二环脒

Synthesis of Bicyclic Heterocycles Containing an N-O Bond and Marine Butenolides

含N-O键的双环杂环化合物和海洋Butenolides的合成

Synthesis of an Receptor Containing Chiral Bicyclic Guanidine for Amino Acids

含手性双环胍的氨基酸受体的合成

In this paper, the ideals, bi-ideals and dual-principal bi-ideals of rectangular band, completely simple semigroup, semilattice, Clifford semigroup, matrix unit semigroup, bicyclic semigroup are depicted.

本文给出了矩形带，完全单半群，半格，clifford半群，矩阵单位半群的理想，双理想与双主双理想的刻画。

Synthesis and Catalytic Activities of Bicyclic Chiral Ammonium Salt Phase-Transfer Catalysts Based on Natural Amino Acids

基于天然氨基酸的双环手性季铵盐相转移催化剂的合成及催化性能研究