环渤海地区膜法海水淡化预处理工艺探讨

海水淡化是环渤海地区经济发展的重大课题.海水预处理是淡化的关键过程.文章结合渤海湾地区海水水质的特点,讨论了膜法海水淡化预处理工艺的选择,设计时对水温,浊度变化的考虑.对连续膜过滤工艺的类型和特点作了介绍.     

扇形板贴敷C-276的工艺研究

对烟气加热器（GGH）扇形板贴敷C276镍基合金板的焊接工艺进行了试验研究，并对焊材性能和点焊设备进行了工艺试验，在对试验结果分析的基础上确定了最佳的工艺参数，贴敷强度完全满足设计图纸要求。为同类产品结构的加工提供了可参考的工艺参数和实践经验。     

Structural integrity analysis of axially cracked pipelines using conventional and constraint-modified failure assessment diagrams

This study explores applications of the failure assessment diagram (FAD) methodology to predict the failure behaviour for high pressure pipelines with planar defects having different geometries (i.e., crack depth and crack length). One purpose of this investigation is to assess the capability of FAD procedures in integrity analyses of high pressure pipelines with varying crack configurations. Another purpose is to address the effectiveness of constraint-based FADs to predict burst pressure of low-constraint cracked pipelines. Full scale burst testing of end-capped pipe specimens with axial surface flaws provide the data needed to compare the failure predictions derived from the FAD procedures. The analyses reveal that the degree of agreement between predicted pressures and experimentally measured values depends rather markedly on the crack size for the tested pipes. Moreover, the analyses also show a possible weak dependence of the predicted pressures on the constraint-based correction scheme. Overall, the results validate the use of FAD-based methodologies for defect assessments of axially cracked pipelines.     

电子航图的颜色校正技术研究

电子航图在飞行仿真领域有着重要应用,然而由于局部纸质航图尺寸、来源及扫描设备等因素的影响,扫描得到的各个子航图颜色不一致,严重影响航图的整体效果.因此本文重点讨论了电子航图的颜色校正问题,利用相郊子航图间的重重叠域,采用线性映射变换的方法,在RGB、YIQ、YUV、HIS 4种颜色空间下对电子航图进行校正和比较.实验结...     

Geopolymerisation of a silica-rich tailing

A silica-rich tailing from vanadium extraction has been used for geopolymer synthesis in combination with metakaolin (MK) as an additional-Al source. Results show that alkaline roasting pretreatment effectively enhance geopolymerisation ability of the tailing in terms of XRD analysis and leaching tests. Strengths of samples can be improved by adding proper quantities of MK, or appropriately raising curing temperature. Curing temperature also affects the Si/Al ratio since higher curing temperature is more favorable for releasing Al. The highest compressive strength of 55.7 MPa can be obtained.     

基于机载激光技术的地形图制作流程

对比传统航空摄影地形图制作流程和LiDAR技术地形图制作流程,分析了两种方法获取数据的区别,并结合实例阐述了基于机载激光扫描技术的地形图制作方法,指出了采用该技术制作地形图的优缺点,以期指导实践。     

三台阶七步流水作业法在隧道施工中的应用

针对国内隧道施工中遇到的种种难题,结合贵广铁路GGTJ-6标工程实例,介绍了三台阶七步流水作业法的特点及作业程序,具体阐述了该方法施工时的注意事项和技术要点等内容,并指出其优点,以期指导今后同类隧道工程施工。     

混凝土箱涵顶进施工及质量控制措施

首先介绍了混凝土箱涵顶进施工的发展历程和工艺流程,接着归纳了顶进施工过程中常见的病害,并提出了相应的预防和补救措施,为以后工程实践提供借鉴。     

指纹采集系统的设计以及图像预处理的研究

应用MBF200指纹采集芯片配合USB2.0接口技术,设计了一个基于DSP的指纹采集系统,并用TI公司的TMS320VC5402芯片对指纹图像进行了图像预处理。该系统完成了所有软硬件设计与调试。实验表明,该系统简单可行,实用性强。     

H2O2预处理联合生物厌氧降解对烟煤孔隙的影响

为研究H₂O₂预处理联合生物降解对煤孔隙的影响,利用浓度为0.05%H₂O₂对烟煤进行预处理,采用煤层气产出水富集获得的高效菌群进行厌氧降解煤产甲烷实验,通过气相色谱仪检测甲烷含量,通过低温液氮吸附对煤孔隙发育变化进行表征。结果表明:利用H₂O₂预处理烟煤显著提高了生物甲烷产量;预处理对煤孔隙类型没有显著影响,但残煤的吸附量减少,有利于原位煤层气的抽采;经预处理后,煤样的微孔和中孔孔容增加,而过渡孔孔容降低。经生物降解后,残煤的总孔容和比表面积均显著降低,可能是微生物代谢产生的可溶有机质滞留积累在煤中,从而堵塞了煤孔隙所导致。