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In this paper, a quaternary ammonium salt of chitosan was synthesized and the factors affect on the solubility or degree of substitution of product, such as the concentration of alkali, the time of basification, the content of water in system, the time of dispersing and the method of adding epoxyproryltrimethylammonium chloride, were discussed in detail. The product was characterized by IR, DSC, TG and X-RAY diffraction. The effects of time, humidity and temperature on the gases permeability of the quaternary ammonium salt of chitosan film were researched.

本论文研究了壳聚糖季铵盐的合成反应，对碱化浓度、碱化时间、水的含量、分散时间和醚化剂的加入方式等因素对制备反应的影响进行了考察；应用红外光谱、DSC、TG以及X-射线衍射对产物进行了表征；探讨了时间、湿度和温度对壳聚糖季铵盐膜透气性的影响。

It is found that the former provide more uneven circular stress state than the latter after comparing the circular stresses both of intrados and extrados,which extrados stress is large and intrados stress is small.That is confirmed by the results of experiment that the practical burst pressure...

结论认为，内压作用下的弯管结构属于有力矩旋转壳，整体环壳第二弯曲半径由外拱区的正半径变化为内拱区的负半径，引起应力性质的变化，只考虑薄膜应力的弯管内压爆破理论存在不安全的因素。

This paper studies the granite growth, development and emplacement as well as their relations to the tectonic dynamic background and to reaction of ocean crust, continental crust and mantle. Thus, not only the contents of pluton study are enriched, but also new evidence for the tectonic evolution, plate kinematics and dynamics are obtained, indicating that the study of formation process and deformation reworking of plutons can provide more information on plate tectonic and continent dynamics, so they should be studied more.

本文研究了花岗岩体的成因、生长演化、形成定位及与构造动力学背景的关系，并注意与陆壳、洋壳、地幔三者之间相互作用的关系，这样，一方面丰富了花岗岩研究内容，提高了花岗岩研究程度；另一方面也对探索东秦岭地区大地构造演化及动力学等问题提供了新的证据和认识，表明在板块构造、大陆动力学研究方面，花岗岩体形成过程等方面的研究也能提供难得的信息，今后应注意加强研究。

The main content and results are showed as follows:(1)Chitosan was degraded by high pressure homogenization, and its effect increased with molecular weight of original chitosan, pressure and number of cycles, decreased with the concentration of chitosan, while both the concentration of acetic acid or sodium acetate and temperature had a negligible influence. What\'s more, theoretical model was built and the mechanism of homogenizer was discussed.

2采用高压均质-H_2O_2联合降解壳聚糖，其降解效果随H_2O_2溶液浓度的增大而提高，随壳聚糖溶液浓度的增大而降低，随HAc溶液浓度的增大先升高后降低，随均质压力和温度的升高而提高，随循环次数的增加而提高。

In this paper, we use FEM software ANSYS to simulate. Using FEM to evaluate the strength of pressure hull, the FEM model of outer covering and stiffeners can use shell element to establish, but it may waste much computing time to calculate. Therefore, in this paper, we can evaluate more easier by making use of the idea of effective-width, and considering the stiffener/plating combined moment of inertia.

本文采用有限元素分析软体ANSYS进行求解，在有限元素分析的模拟上，外壳与环肋均可用壳元素建立一实体模型来分析，但是在模型的建立上过於复杂，在解析上也需要更多的时间来计算，因此本文采用有效幅度的观念，考虑环肋与壳板间之组合惯性矩，将环肋部分取梁元素来模拟，如此一来可简化建立模型的困难度，且大大的缩短分析的时间。

From thermal analysis, weight loss occurs pronouncedly at temperatures above 300 oC in air and the residual weight increases with the reaction temperature. The particle size decreases with the increasing ethanol concentration., while the BET surface area decreases when the concentration of water is increased. Pore size measured from the as-synthesized particles is about 2.7 - 4 nm and this becomes slightly smaller after calcination which is about 3 - 5 nm.

TG/DTA中温度上升至约300 oC时，重量开始明显失重，随著合成反应温度上升，最终残留量由1~3%提高为约5~7%，动态光散射粒径分析发现随著乙醇含量增加，煅烧前与煅烧后的粒径尺寸均有下降趋势，随著水含量的增加，比表面积值随著下降，煅烧后的壳层孔隙尺寸约为3~5nm，煅烧前的壳层孔隙尺寸为2.7~4 nm，煅烧后的孔隙度会略为上升。

Based on the FEM,the calculation and analysis were performed for the transient temperature field s and stress fields of the intermediate pressure main steam valve housing under various operating conditions including cold startup,shutdown,strong hot startup,limit hot startup and accidental condition in 200MW unit in power station.

采用有限元方法，计算分析了电站200MW汽轮机中压主汽阀阀壳在冷启、停机、强热启动、极热启动以及事故等工况下的温度场和应力场，得出了阀壳裂纹区各工况下温度场和应力场的变化规律，提出了内壁裂纹区的周向应力是疲劳寿命计算的主要参考量。

Based on the FEM,the calculation and analysis were performed for the transient temperature fields and stress fields of the intermediate pressure main steam valve housing under various operating conditions including cold startup,shutdown,strong hot startup,limit hot startup and accidental condition in 200MW unit in power station.

采用有限元方法，计算分析了电站200MW汽轮机中压主汽阀阀壳在冷启、停机、强热启动、极热启动以及事故等工况下的温度场和应力场，得出了阀壳裂纹区各工况下温度场和应力场的变化规律，提出了内壁裂纹区的周向应力是疲劳寿命计算的主要参考量。

However, so far there are no reports on the effects and mechanisms of chitosan with a special molecular weight on extending the storage life of fruit and vegetable. Here chitosan of a special molecular weight was employed to study its effects and mechanisms on the preservation of strawberry, Huanghua pear, green pepper, tomato, mango.

本试验采用特定分子量的壳聚糖，选择草莓、黄花梨、青椒、番茄、芒果等多种类型果蔬为试材，从不同分子量的壳聚糖最佳配合及其成膜性、抗病性，以及添加助剂的优化和对常温贮藏果蔬保鲜的生理生化效应等方面开展研究。

The efficiency of shell and tube heat exchanger is a core to design of a shell and tube heat exchanger .

管壳式换热器是广泛应用于各个领域的工业设备，在国民经济中具有非常重要的作用，管壳式换热器的效率问题是设计工作的核心。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。