文献翻译——气体检测与气体传感器

第1页外文文献资料Gasdetectionandgassensor1.GasdetectionGasdetectionsystemissafeandnecessaryequipmentfieldsofindustrialandminingenterprises,thesocialpublicutilities,environmentalprotectionetc.Afterdecadesofdevelopment,improvethemaintechniqueindexcanbemeasuredgasspecies,measurementrange,precision,stability,lifeandotheraspects,withthedevelopmentoflargescaleintegratedcircuittechnology,theinstrumentcombinationtominiaturization,multiparameterandintelligentdirection.Newmethanegasdetectionsystemshouldhavethecharacteristicsofintelligent,caninterfereincertainothergasescanwork,canbebyelectronicnose.Thestructureofthesystem,throughthepatternrecognitionmethodforidentificationofmethanegas.Methanegastotheminiaturizationofelectronicsystemsbaseddetectionsystem,shouldbeconsideredindesignandsamplingdevicereducesthevolumeofthesystem,asimplifiedgasandimprovethecircuittomeetthelowpowerrequirement;inadditiontheportabledetectionsystemoperatorisnormallysitepersonnel,belongingtothenonprofessionalpersonnel,theoperationofthesystemcannotthecomplex,sofortheinteractivefunctionofthesystemshouldalsobepaidattentiontointhedesign.Theexistenceofthetraditionalgasselectivityisnothigh,pooranti-interferenceproblembasedonmetaloxidegassensor,detectionsystemwithsinglesensorindetectingifthereisinterferenceofothergases,iseasytoappearthesimilarresponseandmisjudgment.Thispaperdiscussedthehighsensitivitymethanedetectionsystembasedonsinglechipmicrocomputerisametaloxidemicrogassensorarrayasthesensitiveelement,aportablesystemformethanedetectioncombinedwithpatternrecognitiontechnique.Thesignalprocessingcircuitofthewholesystemiscomposedoffourelementsensorarraydevice,gassampling第2页deviceandhigh-speedMCUasthecorecomponent,hastheadvantagesofsmallsize,highaccuracy,stronganti-interferenceabilityandexcellentperformance.Thispaperintroducesworkingprincipleanddesignofthedetectionsystem,wefocusonthedesignoflowpowercircuit.Coalmineproductionsafetymonitoringsystemisinproductionandapplicationathomeandabroad,butitisnotareallysuitableforsmallandmedium-sizedcoalmineproduct,Chinabegantointroducetheproductionofcoalminesafetymonitoringsystemfromtheearlyeightys,aftertheprocessofintroduction,digestionandabsorption,directimitationofmatching,independentdevelopment,butsofarmostoftheproductsarethefaceoflarge-scaleminedesign,butitsstillhassomeproblemstobesolved,suchas:highcost,thesystemsbasicconfigurationistoolarge,highoperatingcost,sensormeasurementstability,adjustthefrequent,shortservicelife,systeminstallation,maintenancecomplex,inconvenientoperation,theman-machineinterfaceispoor,poorreliabilityofsystemequipment.Wemustrelyontheprofessionalmaintenanceteam,thetechnicalstaff,haveahigherqualityrequirements.Themonitoringsystemtechnologytheoryishigherthanthedomesticlevelofdevelopment,buttheapplicationlimitationindomesticcoalmineisstillacertainamountof,suchasthemodeofmanagementofcoalmineproductionindifferentways,thehighpriceisnotsuitablefortheexistingconditionsofdomesticcoalmine,inadditiontothesensortechnologyforreference,theotheronlyhasacertainreferencevalue.Tosumup,thedevelopmentissuitablefortheproductionofsmallcoalminesafetymonitoringsystemoftheimminenttask,accordingtoChinascoalmineproductionandmanagementmode,inaccordancewiththerelevanttechnicalstandardsofourcountry,reliabilityandpracticability,theadvancedproducttechnologyisthekeyoftheprojectlocation.Thebasicstructureofthegasdetectionsystemconsistsofafinecatheter,micropumpandtheairchamberinletpart,single-chipmicrocomputerasthecorecontrol,signalacquisitionandprocessingcircuitandthedisplay,keyboard,PCinterfacecircuit,andPCrunningintheapplicationsoftwareforartificialneuralnetworktraining,thedetectingsystemofthegasdetectionworkstepsis,single-chipmicrocomputertocontrolthegaspump第3页tobedetectedispumpedintothechamber,collectingtheresponsesignalofgassensorarrayandatthesametime,conversion,storageinthedatamemory,thenSCMfromthesaveddataextractedeigenvalue,identifiedbythenetworkforgasidentification,andtheresultsoutputtotheLCDdisplayscreen.Accordingtothecharacteristicsoftheportablesystem,detectionsystemdesignoftheprocessingcircuithassmallvolume,lowpowerconsumption.2.Gassensorclassification2.1SemiconductorgassensorItistheuseofmetaloxidesemiconductormaterial,atacertaintemperature,themanufacturingprincipleofconductivitychangesalongwiththeambientgascomposition.Forexample,thealcoholsensor,istheuseoftwotinoxideinalcoholgasathightemperatures,resistancewilldecreasesharplytheprincipleofpreparation.Semiconductorgassensorcanbeeffectivelyusedformethane,ethane,propane,:butane,alcohol,formaldehyde,carbonmonoxide,carbondioxide,ethylene,acetylene,vinylchloride,styrene,acrylicacidandmanyothergasdetection.Especially,thesensorhastheadvantagesoflowcost,suitableforciviliangasdetectionneeds.Thefollowingtypesofsemiconductorgassensorissuccessful:methane(naturalgas,methane,carbonmonoxide(alcohol),citygas,hydrogensulfide),ammonia(includingamine,hydrazine).Sensorwithhighqualitycanmeettheneedofindustrialdetection.Shortcomings:poorstability,influencedbytheenvironment;inparticular,selectivityofeachsensorisnotonly,alsocannotdeterminetheoutputparameters.Therefore,shouldnotbeusedinaccuratemeasurementrequirementsoftheplace.Atpresent,thesensormainsupplierinJapan(inventor),followedbyChina,hasrecentlyjoinedtheothercountriessuchasSouthKorea,Americainthisaspectalsohasquitealotofwork,butneverintothemainstream!ChineseinvestedinthisfieldofmanpowerandtimeisnolessthanJapan,butovertheyearsbecauseofnationalpolicyandsocialinformationblockandotherreasons,semiconductorgassensorperformancequalityinourcountryispopularinthemarketarefarinferiortoJapaneseproducts,flightsafetytipssafetravelshouldattachimportancetobelievethat,withthemarketdevelopment,furtherriseprivate第4页capital,ChineseproducedsemiconductorgassensortoreachandsurpassJapanhaspointthedayandawaitforit.2.2CatalyticcombustiongassensorThissensorisacatalystlayeronthesurfaceoftheplatinumresistancebyhightemperatureresistant,atacertaintemperature,thecombustionofcombustiblegasinthecatalyticsurface,combustionisplatinumresistancetemperature,resistancechange,changevalueisafunctionoftheconcentrationofthecombustiblegas.Gassensorforselectivedetectionofcombustiblegascatalyticcombustion:anythingthatcanburn,arecapableofdetecting;usuallycannotburn,sensorsarenoresponse.Ofcourse,anythingthatcanburn,candetectthissentencehasmanyexceptions,but,ingeneraltheselectivityisestablished.Catalyticcombustiongassensoraccuratemeasurement,fastresponse,longlife.Theoutputandenvironmentalsensorisdirectlyrelatedtotheriskofexplosion,safetydetectionsensorisakindofdominantposition.Disadvantages:inthecombustiblegasrange,nonselective.Darkfirework,dangerousexplosive.Mostoftheelementsoforganicvaporhaspoisoningeffectonthesensor.Atpresent,thesensormainsupplierinChinese,Japan,England(thecountry)!AtpresentChineseisthebiggestuserofthiskindofsensor(coal),alsohasthebestproductiontechnologyofsensor,althoughtherehavebeenavarietyofagentsinterferenceunderstand,societyofthesensorinthepropagandabutafterall,catalyticgassensorofthemainstreammanufacturerscombustioninchina.2.3ThermalconductivitygassensorEachgas,hasitsownspecificthermalconductivity,thermalconductivitywhentwoandapluralityofgasratedifferenceislarge,canusetheconductivitysensorresolutioncontent,acomponentofthe.Thissensorhasasensorfordetectionofhydrogen,carbondioxide,methanedetectionofhighconcentrationdetection.Thegassensorcanbeusedwithinanarrowrange,limitingfactors.Thisisanoldproduct,therearemanufacturersaroundtheworld.Thequalityoftheproductsallovertheworldthesame.2.4Electrochemicalgassensor第5页Itispartofaflammable,toxicandharmfulgaseshaveelectrochemicalactivity,canbeelectrochemicaloxidationorreduction.Useofthesereactionscanberesolved,gascomposition,gasconcentrationdetection.Electrochemicalgassensorconsistsofamulticlass:(1),primarycelltypegassensor(alsoknownas:Jiafunicellgassensor,alsocalledfuelcellgassensor,alsocalledspontaneouscellgassensor),principleoftheirfellowweuseddrybattery,batteryisonlycarbonmanganeseelectrodegaselectrodeinsteadof.Anoxygensensorasanexample,oxygenisreducedatthecathodetoanode,electronsflowthroughacurrentmeter,leadmetalisoxidizedinthere.Theconcentrationandoxygenisdirectlyrelatedtothecurrent.Thissensorcaneffectivelydetecttheoxygen,sulfurdioxide,chlorine.(2),constantpotentialelectrolysispooltypegassensor,thesensorforthedetectionofreducinggasisveryeffective,itsprincipleandprimarycelltypesensorisnotthesame,theelectrochemicalreactionoccurredinthecurrentitisforcedbythesensor,istheanalysisofarealcoulomb.Thesensorhasbeensuccessfullyusedforthedetectionofcarbonmonoxide,hydrogensulfide,:hydrogen,ammonia,hydrazine,gasandsoon,isthemainsensoroftoxicandharmfulgasdetection.(3),theconcentrationdifferencecelltypegassensors,gasonbothsideswithelectrochemicalactivityintheelectrochemicalcell,willspontaneouslyformedconcentrationdifferenceelectromotiveforce,concentrationandgaselectricpotentialoftherelevant,electrolytetypecarbondioxidesensoroxygensensor,solidelectricsuccessfulexamplesofthiskindofsensoristhecar.(4),thelimitcurrenttypegassensor,asensorformeasuringoxygenconcentrationbyusingthelimitcurrentelectrochemicalpoolassociatedwiththecarrierconcentrationofthepreparationprincipleofoxygen(air)concentrationsensorforoxygendetection,vehicle,andtheconcentrationofoxygeninmoltensteeldetection.Atpresent,themainsupplierofsuchsensorsallovertheworld,mainlyinGermany,Japan,America,arecentadditiontothefewsuppliersinEurope:Britain,switzerland.Chinainthisfieldstartedveryearly,buttheindustrializationprocesseffect.2.5Infraredgassensor第6页Gasinfraredgassensormosthasthecharacteristicabsorptionpeakintheinfraredregion,detectionofcharacteristicabsorptionabsorptionpeakposition,wecandeterminetheconcentrationofagas.Thissensorwasanalysisinstruments,large,butinrecentyears,withthedevelopmentofsensorindustryisbasedonthetechnologyofMEMS,thissensorhasrisenfrom10,45kilogramsofBigMac,reducedto2milliliters(aboutthesizeofthethumb).Theuseofinfrareddetectorwithoutmodulationlightsourcemakestheinstrumenthasnomechanicalmovingparts,maintenancefreerealizationofcomplete.Typesofinfraredgassensorcaneffectivelydistinguishgas,accuratedeterminationofgasconcentration.Thiskindofsensorfordetectionofsuccess:carbondioxide,methane.Atpresent,thesensorsuppliersineurope!Chinesecurrentlyinthisareaisthesemiblank!2.6MagneticoxygensensorThisisthecoreofmagneticoxygenanalyzer,butalsohasachievedthesensorprocess.Itistheuseofoxygenintheaircanbestrongmagneticattractionprincipleofpreparation.Thissensorcanonlybeusedforoxygendetection,goodselectivity.Atmosphericnitrogenoxidescanbeproducedonlysmalleffects,butthecontentoftheseinterferinggasoften,therefore,themagneticoxygenanalysistechnologyisalmosttheonlyselective!Theoldindustrialproducts,therearemanufacturersaroundtheworld.2.7OtherInrecentyears,withtheemergingofnewtechnology,gassensortechnologyisconstantlyhavingthecorrespondingrevolution.Typesofgassensorwithaddingnew.However,somesensorsshouldbelistedcontroversial,ingassensornamesuchas:PIDdetector,althoughisalsousedforthedetectionofgas,eventhoughthevolumeassmall,but,unabletotrulyrealizethemaintenancefree,therefore,theequipment,nomatterhowsmallthesize,shouldbelistedintheinstrument.第7页中文翻译稿气体检测与气体传感器1.气体检测气体检测系统是工矿企业、社会公用事业、环境保护等领域必备的安全装备。经过几十年的发展，在可测气体种类、测量范围、精度、稳定性、寿命等主要技术指标方面均有明显提高，随着大规模集成电路技术的发展，仪表向微型化、多参数组合与智能化方向发展。新型甲烷气体检测系统应具有智能化的特点，能在一定其他气体干扰的情况提下工作，可以采用电子鼻。系统的结构，通过模式识别方法辨识甲烷气体。以小型化的电子系统为基础的甲烷气体检测系统，在设计上应考虑减小系统的体积、简化气体的进样装置和改进电路以满足低功耗要求等问题；另外便携式检测系统的操作者通常情况下是现场人员，属于非专业人员，系统的操作不能复杂，因此对于系统的人机交互功能在设计上也应得到重视。传统的基于金属氧化物气体传感器存在气体选择性不高、抗干扰性差的问题，采用单个传感器的检测系统在检测中如果有其它气体干扰，容易出现相似的响应而出现误判。本文所讨论基于单片机的高灵敏度甲烷检测系统是以微结构金属氧化物气体传感器阵列为敏感元件，结合模式识别技术进行甲烷气体检测的便携式系统。整个系统由四单元传感器阵列器件、气体进样装置及高速单片机为核心的信号处理电路组成，具有体积小、准确度高、抗干扰能力强等优良性能。本文要介绍该检测系统的工作原理和设计，着重于低功耗电路的设计。煤矿生产安全监控系统虽在国内已有生产和应用，但还没有一种真正适合于中小型煤矿使用的产品，我国从八十年代初期开始引进煤矿生产安全监控系统，历经了直接引进、消化吸收、仿制配套、自主开发的过程，但迄今为止的产品大多都是面对大型矿井设计的，而且自身尚有一些有待解决的问题，如:造价高，系统最基本的配置过于庞大，运行费用大，传感器测量稳定性差，调校频繁，寿命短，系统安装、维护复杂，操作不便，人机界面较差，系统设备可靠性差。必须依赖专业的维护队伍，对人员技术，素质有较高的要求。国外的监控系统技术理论上讲高于国内发展水平，但应用于国内煤矿尚有一定的局限性，如煤矿管理模式生产方式的不同，价格过高不适于国内煤矿现有条件，除在传感器技术方面可供借鉴外，其它仅具一定参考价值。综上所述，开发研制适用于中小型煤矿生产安全监控系统的任务迫在眉睫，而根据我国煤矿生产和管理模式，依照第8页我国的有关技术标准，其技术的先进性、产品的可靠性和实用性则是本项目的关键所在。检测系统基本结构由细导管、微型抽气泵和小气室组成的气体进样部分，以单片机为核心的控制、信号采集处理电路以及显示、键盘、PC接口电路，还有在PC机上运行的用于人工神经网络训练的应用软件，检测系统进行气体检测的工作步骤是，单片机控制抽气泵将待检测的气体抽入气室，同时采集气体传感器阵列的响应信号，并进行转换，储存在数据存储器中，然后单片机从保存的数据中提取特征值，由识别网络进行气体识别，并将结果输出到LCD显示屏幕上。针对便携式系统的特点，检测系统设计了具有较小的体积、较低功耗的处理电路。2.气体传感器分类2.1.半导体式气体传感器它是利用一些金属氧化物半导体材料，在一定温度下，电导率随着环境气体成份的变化而变化的原理制造的。比如，酒精传感器，就是利用二氧化锡在高温下遇到酒精气体时，电阻会急剧减小的原理制备的。半导体式气体传感器可以有效地用于：甲烷、乙烷、丙烷、丁烷、酒精、甲醛、一氧化碳、二氧化碳、乙烯、乙炔、氯乙烯、苯乙烯、丙烯酸等很多气体地检测。尤其是，这种传感器成本低廉，适宜于民用气体检测的需求。下列几种半导体式气体传感器是成功的：甲烷（天然气、沼气）、酒精、一氧化碳（城市煤气）、硫化氢、氨气（包括胺类，肼类）。高质量的传感器可以满足工业检测的需要。缺点：稳定性较差，受环境影响较大；尤其，每一种传感器的选择性都不是唯一的，输出参数也不能确定。因此，不宜应用于计量准确要求的场所。目前这种传感器的主要供应商在日本（发明者），其次是中国，最近有新加入了韩国，其他国家如美国在这方面也有相当的工作，但是始终没有汇入主流！中国在这个领域投入的人力和时间都不亚于日本，但是由于多年来国家政策导向以及社会信息闭塞等原因，我国流行于市场的半导体式气体传感器性能质量都远逊于日本产品，“乘机安全小贴士”安全出行要重视相信，随着市场进步，民营资本的进一步兴起，中国产的半导体式气体传感器达到和超越日本水平已经指日可待。2.2.催化燃烧式气体传感器这种传感器是在白金电阻的表面制备耐高温的催化剂层，在一定的温度下，可燃性气体在其表面催化燃烧，燃烧是白金电阻温度升高，电阻变化，变化值是可燃性气体浓度的函数。催化燃烧式气体传感器选择性地检测可燃性气体：凡是可以燃烧的，都能够第9页检测；凡是不能燃烧的，传感器都没有任何响应。当然，凡是可以燃烧的，都能够检测这一句有很多例外，但是，总的来讲上述选择性是成立的。催化燃烧式气体传感器计量准确，响应快速，寿命较长。传感器的输出与环境的爆炸危险直接相关，在安全检测领域是一类主导地位的传感器。缺点：在可燃性气体范围内，无选择性。暗火工作，有引燃爆炸的危险。大部分元素有机蒸汽对传感器都有中毒作用。目前这种传感器的主要供应商在中国、日本、英国（发明国）！目前中国是这种传感器的最大用户（煤矿），也拥有最佳的传感器生产技术，尽管不