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In this work , 1,8-octodiol, the starting material, reacted with 40% hydrobromic acid to produce 8-bromooctan-1-ol, with the catalytic action of PPTs, its hydroxyl group was protected by 2,3-dihydropyran. Then it coupled with 1-heptaalkyne, by means of P-2 nickel as catalyst, stereoselectivity catalysis hydrogenated, with the catalytic action of acid to take off extremital 2, 3-dihydropyran which protected hydroxy group, then used PCC to oxidize alcohol into corresponding aldehyde.

以1，8-辛二醇为原料，与40%氢溴酸进行单溴代反应，得到8-溴-1-辛醇，在对甲苯磺酸吡啶盐的催化下与2，3-二氢吡喃反应，保护分子中的羟基，再与1-庚炔进行偶联，以P-2镍为催化剂立体选择性催化加氢，酸性条件下脱末端的2，3-二氢吡喃对羟基的保护，使用氯铬酸吡啶盐将醇氧化成醛。

Three strains of bacteria were isolated from haemolymph, hepatopancreas, ascites and muscle of the diseased Eriocheir sinensis caused by aeromonas. All of the three isolates were Gram-negative rods, motile by means of single polar flagella, and were facultatively anaerobic; Glucoce was catabolized with production of acid and gas; Oxidase was positive.

利用硫酸铵盐析、Sephadex G-100凝胶层析和DEAE-Cellulose离子交换柱层析等方法，从其胞外产物中分离纯化出了2种胞外蛋白酶，用SDS-PAGE电泳测得两种蛋白酶的分子量分别为39.6kD和20kD.39.6kD蛋白酶活性在50℃～60℃范围内热稳定性最好，最适pH为9，而20kD蛋白酶的最适温度为50℃，最适pH为8。

In this paper, based on the knowledge about the change in the microstructures and mechaniacal properties of the cast irons with the influence of temperature, stress and thermo—mechanical circulated load in working cycle of ingot mould, the temperature and stress fields have been analysed by means of thermo-elastic-plastic finitive element, and futher, the behavior of thermal stress factors in every working cycle of the mould have been investigated, by which principles for optimum design of ingot mould's structure has been put out.

本文以钢锭模一个使用周期内的温度场、应力场及热一力循环载荷作用下铸铁的组织结构和力学性能的变化规律为基础。利用热弹塑性有限元法对钢锭模使用过程中的温度场及应力场进行了分析，并进一步研究了钢锭模在每个使用周期间的热应力参数的变化规律，提出了钢锭模结构优化设计的基本原则。

Hexaazatriphenylene derivatives were designed and synthesized by introducing methoxyphenyl or fluorenyl peripheral aryl substituents,and the effect of these aromatic substituents on their optical properties and bandgap were characterized by means of UV-Vis absorption spectroscopy,fluorescence spectroscopy and electrochemical cyclic voltammogram.

结果发现，芴和甲氧基苯芳香基团的引入使三亚吡嗪化合物的接收电子能力显著提高，LUMO能级从化合物1a的-3.50 eV降低到化合物1b的-3.68 eV和化合物1c的-3.66 eV，并伴随着吸收光谱和荧光光谱的显著红移，最大吸收和发射峰从化合物1a的413和432 nm红移到化合物1b的460和543 nm以及化合物1c的479和552 nm。

At an early stage in the evolution of the high-speed diesel a variable timing device was introduced in the pump drive coupling, taking the form of a helically splined coupling by means of which the angular relation between driving and driven shafts could be varied by manual or automatic control.

在高速柴油机发展的早期，可变的正时装置被引用到油泵驱动联轴节上，采用螺旋式花键套管的形状，驱动轴和从动轴之间的相对角度可以通过手动或自动控制进行改变。

By means of GC-MS-Ms method, the multiple series of age-related and taxon specific biomarkers are tested in source rocks and oil samples from Liaohe oilfield and Tarim basin, which are hard to be detected by conventional GC-MS method. They are steranes, methylsteranes, Tricyclic and tetracyclic diterpanes, methyl hopanoid alkanes and hexacyclic hopanoid alkanes, etc.

利用色谱－质普－质普方法在辽河与塔里木盆地源岩和原油样品中，检测出了多个系列时代相关及特定种属生物标志物，包括：降胆甾烷系列、甲基甾烷及甲藻甾烷系列、三环二萜烷及四环二萜烷系列、六环蒮烷及甲基藿烷系列等等，这些化合物很难用常规GC-MS形方法检测到。

By measuring the vapor-liquid equilibrium of ethanol- hexamethylene -NaI and verifying the data by means of ternary Gibbs-Duhem equation,the data of the vapor-liquid equilibrium of ethanol- hexamethylene -NaI were in agreement with both criterions.

假定NaI的平均活度系数可表示为盐浓度平方根(m1/2)的幂级数，采用全部合格的汽液平衡数据拟合出幂级数中的各项参数，从而获得在双液比固定条件下盐在非水混合体系中的活度系数。

In the experiments, by means of the advantages of IBAD technology, Ni-Nb amorphous films of about 0.5 μm thick were prepared. And the mechanical and electrochemical properties of the films were investigated by nanoindentation tests and polarization measurements, respectively.

实验中还利用IBAD在技术上的优势，制备了厚度约为O.5μm的Ni-Nb非晶薄膜，并通过纳米压痕测试和电化学极化测量的方法对其力学和电化学性能进行了研究。

In this paper,the condition that gas flow through wood in the pattern of linear flux wasdetermined from the theories of thermodynamics and fluid mechanics.The expression of flow-resistor of tracheids is reduced with the continuity equation and the equation of motion indifferential form.The flow-resistor network is constructed by means of the theory ofpercolation.The equivalent flow-resistor was evaluated by utilizing the real spacerenormalization approach.

本文根据针叶材管胞的解剖结构，运用孔隙介质流体力学的理论，导出了管胞关于气体渗透流阻的数学表达式；继而根据管胞纹孔在三个纹理方向上的连接特性，利用管胞流阻建立了一个描述针叶材三个纹理方向气体渗透性的三维流阻网络；然后运用实空间重整化变换的方法，求解试件流阻网络三个纹理方向的等效流阻，并由此计算试件相应的气体渗透系数；最后用我国南方常见的人工林马尾松木材试件进行渗透系数实际测量，与理论计算结果进行对比分析，以验证三维流阻网络及其理论的准确性。

Firstly, by means of the algorithm, a model of tourism route analysing was built after taking some hypotheses and predigestion, secondly, a indirected graph for tourism route analysing was generated via the information about travel industry sites, information about roads and finally this algorithm was investigated by adopting the motheds of giving all conditions and Dijkstra algorithm.

该算法通过一定的假设和简化建立旅游路线分析模型，利用旅游景点信息和公路信息生成旅游路线分析无向加权连通图。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。