大型LNG储备站蒸发气(BOG)产生量及其特点的分析

近年来随着国内LNG接收站的建设运营和储运系统的完善,如何在使用LNG过程中减少损耗和提高LNG蒸发气(BOG)的回收利用率成为学术和工程界的关注热点之一。本文通过给定大型LNG储备站,计算各种工况下BOG的生成量,分析其特点,为以后的LNG储备站项目BOG回收利用提供参考。通过计算分析表明,在大型储备站设计中不同气源条件对应的BOG最大产生量工况不同,储备站正常运行(无气相外输)过程中储罐热输入、管线热输入产生的BOG量为稳态量,约占BOG生成总量的71.7%~84.1%,装、卸船和槽车置换产生的BOG量为动态量,约占BOG生成总量的15.9%~28.3%。BOG回收利用液化规模可设为贫富LNG产生BOG量的平均值。     

基于改进人工蜂群正余弦优化的红外图像分割方法

针对红外图像背景复杂且分割难度较大等问题,提出了一种改进人工蜂群正余弦优化的红外图像阈值分割方法.首先是将二维Otsu函数作为蜂群算法的适应度函数;其次采用混沌对立的学习方法和差分进化的方法改进了初始化种群和蜜蜂搜索方程;然后利用改进的蜂群算法优化阈值,缩小阈值的搜索区域;最后利用正余弦法计算出全局最优解,该最优解即为...     

机器人辅助激光超声检测系统及参量匹配方法

为解决飞行器复合材料构件的非接触、高精度无损检测问题,提出基于关节型机器人的激光超声检测系统及光声学参量匹配方法。采用有限元方法建立层状复合材料模型,计算分析材料层状各向异性导致激光超声的非对称分布、声束倾斜和畸变特征,结合实验分析得出利用激光超声表征分层的光声学参量匹配方法。在系统设计上,利用1 064 nm波长的Nd:YAG脉冲激光器激励超声波,利用基于光折变效应的双波混合干涉测量系统探测超声信号,激励和探测激光由光纤传导并投射至被检测工件表面,采用精密六轴关节型机器人作为C型扫描装置,建立系统的实验室原型,实现碳/环氧复合材料试样的C型扫描检测,得到试样中模拟缺陷的分布、形状和尺寸特征,验证了检测系统及参量匹配方法的有效性。研究结果表明,研制的机器人辅助激光超声检测系统可以实现碳/环氧复合材料内部直径1 mm以上分层的检测与成像,在飞行器复合材料构件的无损检测方面具有应用前景。     

Design and dynamic simulation of hydraulic system of a new automatic transmission

A new hydraulic system of a novel automatic transmission (AT) was designed. The dimension and structure of valves and cylinders were designed by theoretical calculation. The dynamic simulation model of hydraulic system of AT was established by ITI-SimulationX. Simulation results and theoretical design results were compared to confirm the simulation model. Based on the confirmed simulation model, the simulation results of pressure and flow of the hydraulic system were analyzed. The dynamic simulation method is very helpful for designing and analyzing the performance of hydraulic system and further optimization design. The theoretical design method and dynamic simulation model are feasible for the real industrial applications. The research results can be used in hydraulic system design and optimization. Foundation item: Project(911901204) supported by Youth Innovation Foundation of Beijing University of Aeronautics and Astronautics     

基于FPGA控制的数字化语音存储与回放系统

数字化语音存储与回放系统的作用是对语音进行录音和放音,并实现数字化控制。能够做到语音回放的方法有很多,本课题研究的是基于FPGA控制下的语音存储与回放系统。     

济钢320m2烧结机燃料破碎系统改造

介绍了济钢320m2烧结机燃料破碎系统投产初期遇到的问题以及解决方法.通过技术改造,取得了良好的运行效果和经济效益.     

Gold Nanoparticles and g‐C3N4‐Intercalated Graphene Oxide Membrane for Recyclable Surface Enhanced Raman Scattering

Toxic organic pollutants in the aquatic environment cause severe threats to both humans and the global environment. Thus, the development of robust strategies for detection and removal of these organic pollutants is essential. For this purpose, a multifunctional and recyclable membrane by intercalating gold nanoparticles and graphitic carbon nitride into graphene oxide (GNPs/g‐C₃N₄/GO) is fabricated. The membranes exhibit not only superior surface enhanced Raman scattering (SERS) activity attributed to high preconcentration ability to analytes through π–π and electrostatic interactions, but also excellent catalytic activity due to the enhanced electron–hole separation efficiency. These outstanding properties allow the membrane to be used for highly sensitive detection of rhodamine 6G with a limit of detection of 5.0 × 10^?14m and self‐cleaning by photocatalytic degradation of the adsorbed analytes into inorganic small molecules, thus achieving recyclable SERS application. Furthermore, the excellent SERS activity of the membrane is demonstrated by detection of 4‐chlorophenol at less than nanomolar level and no significant SERS or catalytic activity loss was observed when reusability is tested. These results suggest that the GNPs/g‐C₃N₄/GO membrane provides a new strategy for eliminating traditional, single‐use SERS substrates, and expands practical SERS application to simultaneous detection and removal of environmental pollutants.     

多功能DBHTV传输短节的设计与开发

简要介绍了多功能井下超声成像测井仪的总体构思，然后较详细地阐述了其中的一个关键部分-传输短节的设计与开发过程。在短节中应用了单片机系统和FPGA技术，实现了一种包括大数据量井下超声成像测井仪在组合测井新方法，为今后井下超声成像测井仪的发展拓宽了道路。     

高效方坯连铸机集成优化设计研究

在对方坯连铸关键技术参数综合研究的基础上 ,以实现正确操作和提高工艺性能为目标而进行的具有世界先进水平的高效方坯连铸机集成优化设计研究已经在实际工作条件下得到验证 ,结果证明可很好地满足质量和产量之间的相互关系。