人β-干扰素核基质结合区序列的克隆与分析

采用酚/氯仿抽提、乙醇沉淀提取人基因组DNA,根据GenBank报道的序列设计引物,PCR扩增人β-干扰素核基质结合区(matix at tachment region,MAR),琼脂糖凝胶电泳鉴定,连接T-载体,测序,分析其序列特征。结果显示PCR扩增出800bp条带,与预期片段大小相符。测序结果显示克隆的片段序列和报道的序列同源性为97%,克隆的DNA片段具备典型的MAR特征。结果显示我们成功从人基因组克隆了人β-干扰素MAR序列。     

管道对口器技术及方案研究

水下油气管道维修是人类开发海洋资源的重要保障,文中对西方发达国家正在研究或使用于铺设、维修管道的对口器进行了综述,并针对海底油气输送管道维修目标提出了一种对口器的总体方案.对于追踪国外先进科技,设计适合维修作业环境的对口器,提高我国水下作业技术有重要的意义.     

桩基桥墩的振动特性及木桩基础的病害分析和测试

通过对桥墩的振动测试，掌握木桩腐朽后桥墩的振动特性变化，并对其基础进行挖验，以证实评判结果的正确性。据此制定木桩腐朽严重程度的评判标准。     

日本将资助国内造船业以提高国际竞争力

据《深圳特区报》报道,日本政府在3月初的一次内阁会议上通过了一项扶助本国造船业的法案,对该国若干特定的船舶制造企业采取临时资助措施,以免失去在国际造船业的竞争     

UM71无绝缘轨道电路的调试及联锁关系

介绍UM71模拟电路的制作过程,设备调试步骤,并举例说明联锁试验的技术条件,区间信号联锁的相互关系.     

海底犁式挖沟机犁体曲面优化设计(英文)

The plow of the submarine plowing trencher is one of the main functional mechanisms, and its optimization is very important. The design parameters play a very significant role in determining the requirements of the towing force of a vessel. A multi-objective genetic algorithm based on analytical models of the plow surface has been examined and applied in efforts to obtain optimal design of the plow. For a specific soil condition, the draft force and moldboard surface area which are the key parameters in the working process of the plow are optimized by finding the corresponding optimal values of the plow blade penetration angle and two surface angles of the main cutting blade of the plow. Parameters such as the moldboard side angle of deviation, moldboard lift angle, angular variation of the tangent line, and the spanning length are also analyzed with respect to the force of the moldboard surface along soil flow direction. Results show that the optimized plow has an improved plow performance. The draft forces of the main cutting blade and the moldboard are 10.6% and 7%, respectively, less than the original design. The standard deviation of Gaussian curvature of moldboard is lowered by 64.5%, which implies that the smoothness of the optimized moldboard surface is much greater than the original.     

用等效惯矩法计算铁路轻型桥墩的B值

某些形式的轻型墩的横向宽度不能直接量取,因此可以虚拟一实体墩,以建立虚拟实体墩与轻型墩的惯性矩等量方程,解出虚拟实体墩的横向宽度,并以此做为轻型墩的横向宽度,计算出墩顶横向振幅及桥墩横向自振频率通常值。