有两个分子的

A hydrogen molecule consists only of two hydrogen atoms with the same atomic weight.

氢分子仅有两个原子量相同的氢原子所组成。

They had suppressed the cathodic process of carbon steel electrode. Their inhibition performance was also related with their molecule stereo conformation and electron configuration. Four of bis-(1, 1'-benzotriazoly)-α,β-diamide compounds linked via-CO 〓CO-chain were synthesized and certified by IR and 〓H-NMR. The minimum energy conformations of these compounds were obtained by MM2 forcefield program. The two benzotriazole moiety in BBT1 was more planar than in other compounds. This was beneficial in increasing the inhibition effects of BBT1. In 0.5M H〓SO〓 solution, BBT1 suppressed anodic corrosion reaction. In 3%NaCl solution, BBT1 suppressed both cathodic and anodic corrosion reactions. 1- [ (1'-imidazolly)-methyl] benzotriazole was synthesized by Mannich reaction.

合成了四个通过-CO〓CO-连接的双（1，1'-苯并三唑）-α，ω-二酰胺化合物，采用MM2分子力学程序优化了它们的分子结构，双（1，1'-苯并三唑）-α，ω-二酰胺化合物的缓蚀作用与其分子内两个苯并三唑单元的空间取向有关系，良好的平面性有利于苯并三唑二聚体的吸附和缓蚀作用，苯并三唑二聚体BBT1分子内两个苯并三唑单元近似平行，所以显示出较好的缓蚀效果。0.5M硫酸中BBT1主要抑制铜的阳极溶解的电化学反应；3％NaCl溶液中，BBT1对铜的阳极溶解和氧的阴极还原过程均有抑制作用，相比较而言对阴极过程的抑制作用更大一些。

In order to enhance its resistance to bacterial blightand lepidopteran such as leaffolder, striped stem borer and yellow stem borer etc, we intergessed Xa21 and Bt genes into the genetic background of 93-11 by backcross scheme, combining with molecular marker-assisted selection and phenotypic selection. Through three backcross and two self generations, eight families that have homozygous Xa21 and Bt genes were obtained in the BC3F3 families. Two families show higher recovery percentage of 93-11 even up to 90.59%.

为了进一步提高其对白叶枯病的抗性、同时增加其对水稻鳞翅目害虫（如稻纵卷叶螟、二化螟和三化螟等）抗性，利用常规回交育种方法和结合分子标记辅助选择将Xa21基因和Bt基因同时导入93-11中，在BC3F3家系中筛选到8个家系含纯合的Xa21基因和Bt基因，其中有两个家系与93-11比较其遗传背景的回复率很高，达到90.59%。

Uric acid in the human body has two main sources: from a small number of protein-rich foods from decomposition; most of the body from amino acids,-ribose, and other small molecules, nucleic acid synthesis and catabolism generated.

人体内的尿酸主要有两个来源：小部分从富含核蛋白的食物中分解而来；大部分则由体内氨基酸、磷酸核糖、其它小分子化合物合成及核酸分解代谢中产生。

The N + OH reaction system has no energy barrier in the entrance channel on the PES; instead, there are double wells along the reaction path, which leads to that the integral reaction cross sections are not strongly dependent on either translational energy or initial rotational and vibrational state.

计算还显示，由于N+OH反应入口谷没有能垒，而沿着最小能量反应路径有两个势阱，因此反应的积分截面并不强烈依赖平动能和反应物分子的初始振转态。

In order to study how the single rDNA copy takes the role of the double rDNA copies and the function of the inverted repeat, we cloned the 16s rRNA and its leader sequences from Brassic napus and Vicia faba chloroplasts, by using E.

由于rDNA位于反向重复顺序内，所以有反向重复顺序类型的每一个DNA分子上有两个rDNA拷贝，而无反向重复顺序类型的只有一个rDNA拷贝。

The X-ray diffraction reveals that complex 1, consisting of two crystallographically independent fragments A1 and A2, displays an interesting 3D supramolecular network constructed with ABAB sequence through hydrogen bonding interactions.

晶体数据解析表明，化合物1包含有两个单晶碎片A1，A2，通过相互的氢键作用力，以ABAB顺序排列的，构建了有意义的3D超分子网状结构。

The results of DPBMN in n-hexane solution show that there are two non-radiative processes occurring in the local excited state. The decay time constants of ~4 ps and ~ 220 ps are due to vibration relaxation and intersystem crossing processes respectively.

实验结果显示DPBMN分子在非极性溶剂中的区域性激发态(local excited state，LE state)有两个非辐射缓解的过程发生，首先为发生在LE能阶的振动缓解(~ 4 ps)，之后为系统内转换的过程(~ 220 ps)。

In order to study the aldol condensation of 2.15-hexadecanedione on the surface of aluminium, the intermolecular condensation mechanism of acetone occurring on aluminum was simulated by using semi-empirical AM1 method embodied in MOPAC 6.0 program package. The optimized structures and geometry parameters of 5 transition complexes and 4 intermediates were given.First, 2 molecules of acetone coordinated with aluminum by electrostatic attraction.One atom of hydrogen of acetone migrated to aluminum because of t...

为了研究2，15－十六烷二酮在氧化铝表面的环合机理，选择小分子丙酮为模型化合物，用量子化学半经验AM1方法研究双分子丙酮在氧化铝表面的醛醇缩合机理，给出了反应过程中的5个过渡态和4个中间体的结构和几何参数，该催化反应可以认为是氧化铝分子与两分子丙酮分子发生静电络合作用，然后借助氧原子的负电荷导致脱氢并实现缩合，根据中间体的能量变化，推测有较稳定的铝复合物生成。

Therefore, the EL spectra of (Znq_2)_4 is wider than that of Znq_2. 4._2 was synthesized. The analysis of molecular spatial structure and the characterization of material performance of_2 and Liq showed that two Liq molecules and two Naq molecules were connected by Na-O-Na bond bridges to form_2. Compared with Liq,_2 exhibits stronger rigidity in planar molecular structure, larger steric hindrance and intermolecular distance, and much smaller molecular polarity, thus resulting in much longer fluorescence lifetime, much higher fluorescence quantum efficiency, wider energy bandgap and better film formability. When used as light-emitting layer in OLED,_2 shows lower formation probability of excited dimmer and exciplex formation than Liq, thus emits bluer light with higher current efficiency than Liq. When_2 ultrathin film is used as electron injection layer in OLED, it exhibits higher current density, higher luminance, lower turn-on voltage and higher current efficiency than Liq ultrathin film for the existence of sodium ions in_2 ultrathin film. 5. The summarization the relationship between molecular spatial structure and material performance of Alq_3,(Znq_2) and Liq, lead the conclusion that the molecular spatial structure of Mq_n affects its material performance in such aspects as the rigidity of planar molecular structure, intermolecular interaction, molecule stacking mode and intermolecular distance.

制备了_2，通过对_2和Liq的分子空间结构与性能进行分析与讨论，发现_2是通过两个Na-O-Na键桥将两个Liq和两个Naq连接构成的，其分子平面结构的刚性程度强于Liq，空间位阻大于Liq，分子之间的距离大于Liq，分子极性远远小于Liq；_2的荧光寿命长于Liq，荧光量子效率高于Liq，成膜性优于Liq；_2的禁带宽度比Liq大，光致发光光谱中_2的最大发射峰较Liq发生蓝移；当_2在OLED中作为发光层时，激发二聚体与激基复合物的生成几率远远小于Liq，发的光比Liq更蓝，电流效率大于Liq；_2超薄膜中有Na离子的存在，与Liq超薄膜相比，当其在OLED中作为电子注入层时，具有更大的电流密度，更高的发光强度，更低的阈值电压和更高的电流效率 5、对上述Alq_3、Znq_2和Liq的分子空间结构与材料性能之间的关系进行了归纳总结，认为Mq_n的分子空间结构主要在分子平面结构的刚性程度，相邻分子之间的相互作用，分子堆叠的方式和分子之间的距离这四个方面影响其性能。

In this paper, the requirement analysis, design and implementation of the system are introduced in detail.

此论文详细介绍了系统的需求分析，系统设计和具体实现。

In the context of economic globalization is increasingly deepening, China's economy can not be spared.

在经济全球化日益加深的背景下，中国经济不可能做到独善其身。