可燃性气体（蒸气）最小氧浓度的测定

可燃性气体(蒸气)在固定气体(蒸气)浓度下的最小氧浓度还是一个全新课题。对可燃性气体(蒸气)在固定浓度下的最小氧浓度进行了实验测定，为实际工业生产中的安全防爆工作提供了依据。     

A perspective of microplasma oxidation （MPO） and vapor deposition coatings in surface engineering of aluminum alloys

IntroductionInrecentyears,improvingthewearlifeofAl-basedalloyscomponentsinheavysurfacecontactconditionsbytheapplicationofmicroplasmaoxidation(MPO)coatingshasprovensuccessfulundertechnicalandeconomicconsideration.MPOtechnologyhasrecentlybeentakenasarapid,novelandeffectivemeanstoprovidethickceramiccoatingswithexcellenthardnessandload-bearingcapacityforlightalloymaterials,particularlyaluminumalloys[1].TheMPO,alsocalledplasmaelectrolyticoxidation(PEO),isanadvancedtechnologyforroutineanodizing…     

冷蒸气-原子荧光光谱法测定化探样品中痕量汞

建立了冷蒸气-原子荧光光谱法测定化探样品中痕量汞的方法.研究了仪器的工作条件、试剂浓度等因素对汞原子原子荧光强度的影响,探讨了共存离子对汞测定的干扰和消除方法.方法的检出限为0.04ug.L-1,RSD为0.51%～2.90%,加标回收率为91.8%～107.6%.     

混合蒸气浓度对板式换热器换热系数的影响

为研究水-酒精混合蒸气浓度对板式换热器换热器换热系数的影响,自行搭建高气密性实验台,在压力30 k Pa,混合蒸气流量6 kg/h实验工况下,获得了局部凝结换热系数随蒸气干度、流道长度、混合蒸气浓度的变化关系。实验过程中,采用了在板片焊接热电偶的测温方法,实现了气侧板片壁面温度的直接测量。结果表明,凝结换热系数随着蒸气干度增加而增加;换热系数随板长方向上无量纲长度增加而减小;与纯水蒸气比较,1%、2%浓度混合蒸气的传热系数值较高,且浓度为1%时的传热系数高于浓度为2%时的传热系数;5%、10%、20%浓度混合蒸气的传热系数均低于纯水蒸气传热系数,且传热系数随混合蒸气浓度增加而减小。     

Configuration Consideration for Expander in Transcritical Carbon Dioxide Two-Stage Compression Cycle

To investigate the configuration consideration of expander in transcritical carbon dioxide two-stage compression cycle, the best place in the cycle should be searched for to reinvest the recovery work so as to improve the system efficiency. The expander and the compressor are connected to the same shaft and integrated into one unit, with the latter being driven by the former,thus the transfer loss and leakage loss can be decreased greatly. In these systems, the expander can be either connected with the first stage compressor ( shortened as DCDL cycle) or the second stage compressor ( shortened as DCDH cycle), but the two configuration ways can get different performances. By setting up theoretical model for two kinds of expander configuration ways in the transcritical carbon dioxide two-stage compression cycle, the first and the second laws of thermodynamics are used to analyze the coefficient of performance, exergy efficiency, inter-stage pressure,discharge temperature and exergy losses of each component for the two cycles. From the model results, the performance of DCDH cycle is better than that of DCDL cycle. The analysis results are indispensable to providing a theoretical basis for practical design and operating.     

汽车玻璃的秘密

玻璃!玻璃!每辆汽车都安装了不少玻璃,这些大同小异的玻璃扩展了我们的视野,让我们在旅行的途中增添了不少的乐趣。其实呀,在这些看似平常的玻璃背后还藏着许多小秘密呢……咦,那会是什么呢？让我们赶紧去瞧一瞧吧!     

爱与恨的牢狱

毛姆在《面纱》的自序里说,这本小说的灵感来源于但丁《神曲》"炼狱篇"里的诗句"锡耶纳养育了我,而马雷马却把我毁掉"。这是个丈夫对出轨的妻子报复的故事:皮娅是锡耶纳的一位贵妇,她的丈夫怀疑她红杏出墙,但慑于她家族的背景,不敢动手致她于死地,就把她投入了位于马雷马的城堡,以期让她在城堡里的有毒蒸气中死去。但是她迟迟未能毙命,他最终忍无可忍把她从窗子里扔了出去。这个故事激发了他的想象力,他要为这个故事找一个现代的背景,于是《面纱》是他唯一先有故事情节再有人物形象的小说。     

铁与水蒸气反应的实验改进

人教版必修1中采用湿棉花作为水蒸气源,用酒精灯加热还原铁粉的反应,并通过氢气肥皂泡检验氢气的产生,与前人教版教材中采用加热水至沸腾与铁反应的实验相比,在安全性、简易性方面有了很大改进,但经我们实验后发现,实验主要存在以下的问题:     

用大气压知识解决实际问题三例

例1.一个潜水艇位于海面下200米深处,为了使它上浮,需要将水箱中的水用高压气体排出一部分,问:高压气体的压强至少需要多大才能将水箱中的水排出? （海面上大气压为1个标准大气压）解答:海水在潜水艇处产生的压强为P₁,则