查询词典 hydrogen

In order to find screening rules suitable for lead compounds of pesticide,five descriptors:logarithm of partition coefficient of octanol/water,relative molar weight,number of hydrogen-bond donors,number of hydrogen-bond acceptors,polar surface areaand carcinogenic and mutagenic toxicities of 242 fungicides,512 herbicides and 399 insecticides were calculated and analyzed.

1996年，Lipinski通过对2000多种口服药物进行分析，提出了用于药物分子筛选的&5规则&，即化合物疏水常数(CLogP≤5或MLogP≤4.5)，相对分子质量不大于500，氢键给体数不大于5和氢键受体数不大于10[1]。2003年，Andrew等报道了从高通量筛选结果中获取先导化合物的规则：化合物疏水常数≤3，相对分子质量小于450[2]。

Hydrogen always has valence 1, so other elements' valences equal the number of hydrogen atom s they combine with.

元素的特征价数是以该元素一个原子可结合的氢原子数或可从一化合物中置换出的氢原子数来表示。

The mainly conclusions in our research are as flowing: tungsten trioxide powders with 100 nm primary particle are obtained by spray drying,calcination and wet milling process, and an average size of quadric particle composed of agglomerated particles is 0.64 μm; tungtsen powders with 39 nm grain size and 60 -100 nm primary particle are produced directly from previous tungsten trioxide using one step reduction in hydrogen at 700℃, and an average size of quadric particle of tungsten powder is 2.91 μm; tungsten trioxide and copper tungstate compound powders with 100 nm - 200 nm primary particle are produced using ammonia metatungsten and copper nitrate as raw materials by spray drying,calcination and wet milling process;the compound powders are transformed completely into tungsten and copper compound powders by reduction in hydrogen at 700℃,in which tungsten grain size is 59 nm and copper grain size is 51 nm; primary particle size of compound powders is 80 - 120 nm,and an average size of agglomerated quadric particle is 1.86 μm; tungsten nitride powders with 35 nm grain size are prepared from tungsten trioxide powders by nitrogen treatment thoroughly in pure ammonia at 650℃, and an average size of agglomerated quadric particle is 0.64 μm in normal temperature.

研究结果表明：采用喷雾干燥—焙烧—球磨工艺可以制备出粒度约为100nm的WO_3粉体，它们在团聚后形成的二次颗粒平均粒度为0.64μm；采用一步直接氢还原方法可在700℃下从上述WO_3粉体制备出晶粒尺寸为39nm的、一次颗粒粒度为60-100nm的W粉体，其二次颗粒的平均粒度为2.91μm；以偏钨酸铵、硝酸铜为原料，采用喷雾干燥—焙烧—球磨工艺可制备出一次粒度为100-200nm的WO_3和CuWO_4混合粉体；采用氢还原工艺可在700℃下将这种粉体完全转变为W、Cu复合粉体，其中W的平均晶粒粒尺寸为59nm，Cu的平均晶粒尺寸为51nm；复合粉体的一次颗粒尺寸为80-120nm，在常温下团聚后形成的二次平均粒度为1.86μm；采用纯氨氮化工艺可以在650℃下由WO_3粉体制得WN，其晶粒尺度为35nm，在常温下团聚后的二次平均粒度为6.4μm。

The most effective way to solve these problems is on-board hydrogen generation by liquid fuels with high hydrogen density.

解决这些问题的最有效的方法是选择合适的具有高能量密度的液体燃料催化转化在线产氢。

The hydrogen solubility in Pd follows Sieverts law, and hydrogen diffusion through the bulk of the palladium membrane is the rate determining step. Whereas other gases only permeate through the pinholes or gaps in the Pd layer;the permeation can be quantitatively described as a combination of Knudsen diffusion and viscous flow.

氢气在钯膜中溶解渗透服从Sievert定律，并且氢的渗透扩散过程是速率控制步骤；而其他气体则通过膜中的针孔或裂隙进行扩散，其传质过程为Knudsen扩散和粘性流两种传递方式的综和。

Interconersion between these two forms of energy suggests on-site utilization of hydrogen to generate electricity, with the electrical power grid sering in energy transportation, distribution utilization, and hydrogen regeneration as needed.

以氢气作能源可以缓解空气污染，地球变暖得到控制，环境以可持续发展的方式得到保护。氢气可以和电能偶连起来，为交通运输及发电提供能源。

For the fourth part, we first designed a hydrogen bonding-mediated rigidified polymer. The X-ray crystal analysis of its fragment molecules showed the existence of consecutive intramolecular hydrogen bonds, which forced the backbone to adopt a rigidified planar conformation.

在第四部分工作中，首先我们设计了一种分子内氢键控制构象的聚合物，通过对其氢键骨架的单晶培养和结构解析证实在它们的结构中存在三中心氢键使得它们采取平面刚性的构象。

Reforming unit: recycle hydrogen compressor, reforming hydrogen compressor, feedstock furnace, reboiling furnace of deheptane tower

重整单元：循环氢压缩机、重整氢增压机、重整进料加热炉、脱戊烷塔重沸炉

Effects of hydrogen reduction time, hydrogen content and redox circulation on C O oxidation activities of CuO-CoO/Al2O3 and CuO-Ce2O3/Al2O 3 combustion promotors were investigated.

对 CuO-CoO/Al2O3和 CuO-Ce2O3/Al2O3助燃剂受 H2还原时间、还原 H2 含量，以及多次还原-氧化循环处理后对 CO 氧化活性的影响在实验室进行了研究。

Methods: Copper was determined by catalytic kinetic spectrophotometric method which was based on the copper catalyzing oxidation of brilliant green by potassium chlorate and hydrogen peroxide in potassium hydrogen phthalate-sodium hydrate buffer solution at pH4.20. The absorbance was measured at 624 nm.

在pH4.2的邻苯二甲酸氢钾－氢氧化钠缓冲溶液介质中，利用铜离子催化氯酸钾和过氧化氢氧化灿烂绿的指示反应，通过测量624 nm下吸光度的改变，用催化动力学光度法测定痕量铜。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。