摘要：本文研究了承受由轨道传来的重型滞留超载的背对背连接的土工合成材料加筋土挡墙的设计。挡墙设计中使用了简化法则,应用非线性有限元分析,研究了临界断面。发现背对背连接挡墙的应力、应变场与普通加筋土挡墙的完全不同。然而,如果在所提供的刚度范围内使用土工合成材料加固,那么简化设计准则就给出一种偏小的加筋张力和相对于有限元结果的连结力系数。如果采用金属加筋,有限元分析预测的加筋张力就大得多,这种差异是由于背对背连结挡墙对加筋刚度的依赖性而引起的。

摘要：采用石油化工科学研究院的中压加氢裂化(RMc)技术所设计的加氢反应器用于800 kt/a加氢裂化装置以催化柴油、常三、减-蜡油为原料生产重石脑油、轻柴油和重柴油,具有较好的适应性,并从流体力学、传热和传质3方面对反应器内构件进行了分析和优化设计。

摘要：在国内某重点石化装置的国产化设计中,依据可靠度设计思路,对核心设备——反应器及其附属管道的随机振动问题进行了开发研究,初步探索出一套解决该类问题的技术和方法。文章不涉及具体的计算模型和计算参数,而仅对与工程计算紧密相关的重要理论依据和理论要点给予综述。

摘要：In order to solve the serious problems of seeds are covered by residual film and overhead by straw during no-till seeding,a seed furrow cleaning device for no-till maize seeding was developed,which adopted a collaborative cleaning method of rotating spring teeth and curved sliding *** movement process and motion trajectory of throwing residual film and straw were *** maximum distance of throwing to one side in horizontal and maximum height in vertical were *** motion trajectory of adjacent spring teeth was analyzed by Matlab,the motion trajectories of adjacent spring teeth at different speeds of 120 r/min,150 r/min and 180 r/min were achieved,the theoretical analysis results showed that the area of omitted area decreased with the increase of rotation *** on theoretical and simulation analysis of critical parameters,the forward speed of machine,rotation speed of spring teeth,and dip angle between spring teeth and rotary disc were selected as the influencing *** cleaning rate(ScR)and residual film cleaning rate(RFcR)were selected as the response values for three factors and three levels of orthogonal experiment *** optimal combination of the selected parameters was obtained,and the field test verification was also *** results showed that the rotation speed of spring teeth,forward speed and dip angle of spring teeth significantly affect ScR and RFcR were in decreasing *** field test results indicated that when forward speed was 6 km/h,rotation speed of spring teeth was 180 r/min and dip angle of spring teeth was 40°,ScR and RFcR were 88.27%and 84.31%,*** study provides a reference for the development of no-till seeder in Xinjiang and the northwestern regions of china.

摘要：重点介绍了异丁烯在催化剂和相应的工艺条件下聚合反应机理及其影响因素。

摘要：随着技术的发展,计算机辅助电路设计工具已经成为电路设计与开发人员在完成设计任务时的必不可少的设计工具.本文在对Protel 99 SE介绍的基础上,讨论了在Protel 99 SE的上机教学过程中将其划分为分解练习;单元练习;综合练习的教学方法.

摘要：球罐设计中球壳几何参数和面积的计算是设计中的的繁琐工作,该文给出了以球面三角为基准的球壳几何尺寸、面积的数学公式,作为计算程序的数学模型。

摘要：简述清洁生产的要义及实现清洁生产需采取的措施,并举例阐明清洁生产在15kt／a防老剂RT培司水解反应器设计当中的应用。

摘要：镇海炼化工程公司设计的φ1600mm螺纹锁紧环换热器,是国内目前直径最大的螺纹锁紧环换热器。该文对此换热器的选材、结构设计、设计计算、制造等问题进行了较详细的论述和分析,并对螺纹锁紧环换热器使用维护和装拆时应注意的事项提出了建议。