高压氢气罐的裂纹成因分析及强度校核

对洛阳分公司炼油厂重整装置的四台储氢罐在进行压力容器检验时发现的裂纹进行了分析，认为是制造过程中形成的裂纹，并对这些裂纹进行了处理和强度校核。     

某电厂发电机氢气露点波动大及纯度偏低的原因分析与处理

某电厂正常运行期间存在发电机内氢气纯度偏低、露点波动大等问题,经过现场检查及分析为密封油真空箱油水分离异常及密封油中微水含量偏高所致。通过对密封油真空油箱油水分离改造、更换高效的吸附式氢气干燥器、氢侧回油管改造等,彻底解决了氢气纯度偏低、露点波动大的问题。     

发电机氢气湿度大原因分析与处理

介绍了1000MW氢冷发电机组氢气干燥系统的基本情况及运行中氢气湿度偏高对发电机本身的危害,分析了氢气湿度偏高的有关原因及其最终处理情况。     

发电机氢气纯度降低的原因分析

详细介绍了型号为QFSN—600—2型水氢氢汽轮机发电机冷却的基本原理,并从实际运行的角度分析了防止发电机氢气纯度降低的主要策略,同时对影响氢气纯度的各种因素进行了分析。以国华台山电厂4号机组为例,介绍了发电机氢气纯度降低的原因以及实际运行中采取的防范措施。     

H22系列氮氢气压缩机活塞杆断裂事故的调查统计及其原因分析

介绍了活塞杆断裂事故的调查统计、断口分析、原因分析、受力分析比较及其对策。     

供氢系统用氢气阀门的研究现状与发展趋势

氢气阀门是供氢系统的核心组件,本文对供氢系统中常用的阀门类型进行了介绍,对氢气阀门研发中的共性技术问题进行了分析,对氢气阀门技术和产业的发展趋势进行了分析。     

气相色谱-脉冲放电氦离子化检测器分析乙烯、丙烯中的痕量一氧化碳和氢气

建立了气相色谱-脉冲放电氦离子化检测器(GC-PDHID)测定乙烯、丙烯样品中痕量一氧化碳和氢气的方法。对色谱柱、柱温、进样方式等条件进行了优化。采用外标法定量,在一氧化碳和氢气浓度分别为12μL/m3~390μL/m3和52μL/m3~800μL/m3的范围内时,标准曲线R2均大于0.99,一氧化碳和氢气检出限分别为7.6μL/m3和8.6μL/m3。实验结果表明,样品加标回收率在94.74%~110.2%之间,相对标准偏差为0.32%~2.83%,样品分析周期为15min。该方法分离效果好,具有良好的重复性和准确度,检出限低。本方法适用于乙烯、丙烯中痕量一氧化碳和氢气的检测。     

氢气压缩机管道振动的原因分析

通过建立管系振动的有限元分析模型和现场实测,掌握某4M16—47．5型氢气压缩机出口管线的振动特性;利用分析软件对管系进行了结构模态分析,并与实际测得的数据进行对比分析,找出压缩机出口管线剧烈振动的原因,为设计出一套适合现场需求的减振方案提供了依据。     

探空站氢气房的静电危害与防范

氢气房是高空气象探测站的必备设施之一,做好制氢、用氢的各项安全生产工作是确保高空气象探测业务正常运行的关键。静电火花是引起氢气发生火灾事故的重要隐患,特别是在秋冬干燥季节更应该引起高度重视,切实做好氢气房的静电防范工作,以免因小铸成大错。本文从预防静电火花的角度谈谈如何做好探空业务用氢的安全生产工作。     

基于CFD分析方法的氢气碱洗塔腐蚀失效分析

以某石化重整装置开裂碱洗塔为研究对象,分析氢气-碱液两相耦合腐蚀机理和碱洗塔失效原因。采用CFD技术,仿真模拟碱洗塔内部氢气-碱液流动流场,计算两相介质速度和动压力分布,并结合失效材料的化学成分、拉伸力学性能试验及塔内壁表面腐蚀产物分析,确定碱洗塔失效的原因是流动加速腐蚀,即潮湿含HCl的氢气与碱洗塔壁面接触,由于碱液流动存在不均衡性,HCl未与碱液中和而是与壁面发生腐蚀反应。同时,在高速氢气的作用下,腐蚀产物膜发生剥落,从而加速塔体壁面的减薄,最终在内压作用下发生开裂。该研究结果可为类似工艺装置与工况特点的在役承压设备避免相似损伤失效模式提供参考。     

液氢截止阀故障分析与改进

介绍了火箭发动机试验系统高压液氢截止阀的结构特点,及其材料选用、密封和绝热结构等技术问题的处理方法。针对其使用中出现阀杆与阀体之间咬合而无法动作的问题进行了全面的分析,并提出了解决方案。     

DQ-5(2.5)/3.2型中压水电解制氢装置结构及常见故障分析

介绍连电公司DQ-5(2.5)/3.2型中压水电解制氢装置的制氢原理、组成构造,对运行过程中常见故障的原因进行了分析,提出了解决故障的办法。     

Prediction of hydraulic jump characteristics in a closed conduit using numerical and analytical methods

The hydraulic jump is an economical alternative to dissipate energy in the conduit and to reduce erosion at the culvert outlet. In the literature, very limited studies have been reported on the performance of hydraulic jump in a closed conduit. The innovation of this research is to employ a numerical method for the estimation of the hydraulic jump characteristics in a closed conduit with different positive slopes (S₀). The analytical method was used to develop several equations for hydraulic jump and the provided results were compared with the numerical method. The results indicate that the numerical method predicts the flow depth ratio after conduit with higher accuracy (error less than 5%) in comparison to the analytical method (error less than 10%). Furthermore, in the slope of 0.00, the energy loss increases by 16% with increasing the Froude number from 4.617 to 5.562 while this value is 23% and 22% for slopes of 0.01 and 0.02, respectively. Finally, several equations were developed for the prediction of hydraulic jump characteristics in terms of Fr₁, S₀, and conduit depth (D).     

2205双相不锈钢氢致开裂行为的试验分析与模型预测

开展了2205双相不锈钢(Duplex stainless steel,DSS)氢致开裂(Hydrogen assisted cracking,HAC)行为的研究,考察了组织形态对2205双相不锈钢中氢致裂纹萌生和扩展的影响.结果表明,横向组织中的氢致裂纹扩展的长度比纵向组织中的裂纹更明显,裂纹优先萌生的位置在铁素体相...     

氢能源汽车车载超高压气动减压阀的机理与特性分析

分析了车载超高压气动减压阀的工作机理、基本特性及其影响因素．气动减压阀阀芯与阀套在结构上形成压力反馈腔,将负载压力反馈给弹簧,稳定出口压力．分析结果表明：阀内流道的等效阻尼长度和压力反馈腔体积是影响阀出口压力的重要因素．流道等效阻尼越小,阀口关闭越快,出口压力波动越小;压力反馈腔体积越大,其压力缓冲作用越明显,出口压力波动越小,但延迟时间越长．     

燃料电池氢循环喷射器性能分析与结构优化

喷射器以其体积小、无运动部件、不产生寄生能耗等一系列优点,正成为氢燃料电池氢气再循环的理想解决方案.但电堆变工况下喷射器的循环流体与供给流体的高度耦合特性致使其与电堆的匹配和优化难度较大.本文针对燃料电池变负载工况下喷射器引射流体压力与背压耦合变化的情况,采用计算流体力学(CFD)流体力学计算和实验相结合的方法,获取多...     

In vivo monitoring of the transfer kinetics of trace elements in animal brains with hyphenated inductively coupled plasma mass spectrometry techniques

The roles of metal ions to sustain normal function and to cause dysfunction of neurological systems have been confirmed by various studies. However, because of the lack of adequate analytical method to monitor the transfer kinetics of metal ions in the brain of a living animal, research on the physiopathological roles of metal ions in the CNS remains in its early stages and more analytical efforts are still needed. To explicitly model the possible links between metal ions and physiopathological alterations, it is essential to develop in vivo monitoring techniques that can bridge the gap between metalloneurochemistry and neurophysiopathology. Although inductively coupled plasma mass spectrometry (ICP‐MS) is a very powerful technique for multiple trace element analyses, when dealing with chemically complex microdialysis samples, the detection capability is largely limited by instrumental sensitivity, selectivity, and contamination that arise from the experimental procedure. As a result, in recent years several high efficient and clean on‐line sample pretreatment systems have been developed and combined with microdialysis and ICP‐MS for the continuous and in vivo determination of the concentration‐time profiles of metal ions in the extracellular space of rat brain. This article reviews the research relevant to the development of analytical techniques for the in vivo determination of dynamic variation in the concentration levels of metal ions in a living animal. © 2009 Wiley Periodicals, Inc. Mass Spec Rev 29:392‐424, 2010     

HMI-ICP-MS和AAS测定大米中微量元素的方法比较

目的：探讨带高基体进样系统（HMI）ICP-MS测定大米中微量元素的可行性,并与原子吸收（AAS）测定方法进行比较。方法：将大米消解后分别用HMI-ICP-MS和AAS测定其中铁、铜、锌、镉。结果2种方法对国家标准参考物质大米粉的检测结果均在可信范围内。结论：HMI-ICP -MS可以准确快速地测定大米粉中的微量元素,并可以耐受更高的总固体含量。     

Stabilisation of hydrogen bonding in polypropylene glycol at EHL contact region

In the present work, the stabilisation of hydrogen bonding of polypropylene glycol at elastohydrodynamic lubrication (EHL) contact was investigated by in situ observation with a micro‐Fourier transform infrared spectrometer, and the effect of hydrostatic pressure on infrared (IR) spectra was confirmed using a diamond anvil cell. Polypropylene glycols with different molecular weights were used as sample oils. Polypropylene glycol molecules interact with themselves by hydrogen bonding with their hydroxyl groups. Stability of the hydrogen bonding is observed by IR peak shift of the O–H stretching mode (3400–3700 cm⁻¹). In the case of the dynamic condition under EHL, the C–H stretching mode shifted to a higher wavenumber, whereas the O–H stretching mode shifted to a lower wavenumber at the Hertzian contact region. This result means that the hydrogen bonding of polypropylene glycol was stabilised under high pressure, and the stabilisation of hydrogen bonding by pressure was dependent on the molecular weight of polypropylene glycol. Copyright © 2010 John Wiley & Sons, Ltd.     

一种基于机器人自动化煤质分析系统的煤样微量添加与称量模块的特点与应用

本文主要介绍了一种基于机器人自动化煤质分析系统的煤样微量添加与称量模块的技术特点与主要功能,通过阐述机器人自动化煤质分析系统的研发背景来说明该模块研发的重要性及其应用前景,同时提出了需要进一步解决的一些技术问题,希望其不断得以完善,为工业快速发展服务。