燃气报警器-外文翻译及双螺杆挤出活性材料的加工工艺-外文翻译

福州大学至诚学院本科生毕业设计（论文）外文翻译题目：基于单片机可燃气体检测报警器的设计姓名：学号：系别：信息工程系专业：电子信息工程年级：指导教师：（签名）年月日附录：外文文献及译文外文原文1：CombustiblegasalarmCombustiblegasalarmtopreventgasleakageasapowerfulweapon,ithas,however,doesnotseemtohaveattractedtheattentionitdeserves.Thissecurityandhouseholdfireextinguisherscanbeplacedonapar,orevenmorethanthefireextinguisherintothefamilyofthelittlethingsthatmostfamiliesdonotseeitasonething,donotevenknowtherecanbesuchafundamentalsolutiontogaspoisoningandgasexplosion,"theprotectionofGod"exists.Shanghaiasanexample,lastyear,duetopoisoningandcookinggaswaterheateroverflowout,pieceofrubberhoseofftheagingcausedbygasleakageandpoisoningcausedbyatotalof86deaths,accountingforallthegasdataofaccidentswere84%.However,accordingtoanauthoritativedepartmenttoanothersurveyreleasedshowsthatinShanghai,aboutthreemilliongasusers,theinstallationofdomesticgasleakagealarmoflessthan10%.Intheirdailylives,whetheritisgaspoisoningorgasexplosion,becauseofgasleakintothesky.Homelife,nooneisinseparablefromtheuseofgas,nomatterwhatyoudomorepreventivemeasures,butahundredsecretinevitablyverycareful,nottomentionofanyfiresafetymeasuresarenottakenonevenmoredangerousfamily.ThereforeitisnecessarytoprepareaCombustiblegasathomeatanytimefortheownerguardianofthegasappliances,agasalerttothisinvisiblekillerslippedquietlyouttohelptheowneroftheeliminationoffamilyproblemsinthebud,thedomesticsecurityofthegoodhousekeeper,sothatfamilymemberswiththeuseofgas,theuseofheartsatease.Forexample,therearemanyfamiliesoffiregasexplosion,donotknowintheroomfullofgasleakingout,theblinduseofelectricalswitchesandtragedyinaninstantifthereisanalarm,atragedylikethis,canbegreatlyavoided.Combustiblegasalarmintothefamily,willbecomeagoodhomesecuritytohelp,thisisanindisputablefactProductDescription:Detectionofgas:naturalgas,liquefiedpetroleumgas,citygas(H2)Size:115mm*71mm*43.3mm(1)addautomaticsensordriftcompensation,therealandomittedtopreventthefalsepositives.(2)Thefailurepromptedthepolicetoenabletheusertoreplaceandrepair,topreventthenon-reported.(3)MCUcontroltheentireprocess,workingtemperature-40degreesto80degrees.Operatingvoltage:220VACor110VAC,12VDC-20VDCAdditionalfeatures:linkageexhaustfan,themanipulator,thesolenoidvalveNetworking:wirednetworkingfunctions:(NO,NC)Wirelessnetworking:315MHZ/433MHZ(2262OR1527)译文：燃气报警器燃气报警器作为预防燃气泄漏的有力武器，它的出现却似乎并没有引起人们应有的注意。这个在安全防护上可以和家用灭火器相提并论、甚至比灭火器更需要进入家庭的小东西，大多数家庭根本没有把它当一回事，甚至不知道还有这样一个可以从根本上解决煤气中毒和煤气爆炸的"保护神"存在。以上海为例，去年因热水器废气中毒及灶具溢熄、橡皮管老化脱落引起的燃气泄漏和造成中毒死亡的共86人，占全部燃气事故死亡人数据的84%。但据权威部门公布的另一项调查表明，在上海市300万左右的燃气用户中，安装家用燃气泄漏报警器的不足10%。在日常生活中，无论是煤气中毒还是煤气爆炸事故，都因煤气泄漏而起。居家过日子，谁都离不开使用煤气，无论你的预防措施做得多好，但百密难免一疏，更何况对消防安全不采取任何措施的家庭就更加危险。因此很有必要在家里准备一个燃气报警器，随时替主人守护着燃气用具，时刻警惕着燃气这个无形杀手悄悄溜出来，帮助主人将家庭隐患消灭在萌芽之际，成为家庭安全的好管家，让家人使用燃气具时，用得安心放心。例如有很多的家庭煤气爆炸火灾，都是在不知道房间里充满了泄露出来的煤气，盲目动用电器开关而在瞬间发生的悲剧，如果有一个报警器，类似这样的悲剧就可以大大避免。燃气报警器进入家庭，将成为家庭安全的好帮手，这是不争的事实产品说明：检测气体：天然气、液化气、城市煤气（H2）体积：115mm*71mm*43.3mm(1)新增传感器漂移自动补偿功能,真正防止了误报和漏报.(2)报警器故障提示功能,以便用户更换和维修,防止了不报.(3)MCU全程控制,工作温度在-40度~80度.工作电压：220VAC或110VAC、12VDC-20VDC附加功能：联动排气扇、联机械手、电磁阀联网方式：有线联网功能：（NO、NC）无线联网方式：315MHZ/433MHZ(2262OR1527)外文原文2：STC89C52DateSheetDescriptionTheSTC89C52isalow-power，high-performanceCMOS8-bitmicrocontrollerwith8Kbytesofin-systemprogrammableFlashmemory.ThedeviceismanufacturedusingAtmel’shigh-densitynonvolatilememorytechnologyandiscompatiblewiththeindustry-standard80C51instructionsetandpinout.Theon-chipFlashallowstheprogrammemorytobereprogrammedin-systemorbyaconventionalnonvolatilememoryprogrammer.Bycombiningaversatile8-bitCPUwithin-systemprogrammableFlashonamonolithicchip，theAtmelSTC89C52isapowerfulmicrocontrollerwhichprovidesahighly-flexibleandcost-effectivesolutiontomanyembeddedcontrolapplications.TheSTC89C52providesthefollowingstandardfeatures:8KbytesofFlash，256bytesofRAM，32I/Olines，Watchdogtimer，twodatapointers，three16-bittimer/counters，asix-vectortwo-levelinterruptarchitecture，afullduplexserialport，on-chiposcillator，andclockcircuitry.Inaddition，theSTC89C52isdesignedwithstaticlogicforoperationdowntozerofrequencyandsupportstwosoftwareselectablepowersavingmodes.TheIdleModestopstheCPUwhileallowingtheRAM，timer/counters，serialport，andinterruptsystemtocontinuefunctioning.ThePower-downmodesavestheRAMcontentsbutfreezestheoscillator，disablingallotherchipfunctionsuntilthenextinterruptorhardwarereset.VCCSupplyvoltage.GNDGround.Port0Port0isan8-bitopendrainbidirectionalI/Oport.Asanoutputport，eachpincansinkeightTTLinputs.When1sarewrittentoport0pins，thepinscanbeusedashighimpedanceinputs.Port0canalsobeconfiguredtobethemultiplexedloworderaddress/databusduringaccessestoexternalprogramanddatamemory.Inthismode，P0hasinternalpullups.Port0alsoreceivesthecodebytesduringFlashprogrammingandoutputsthecodebytesduringprogramverification.Externalpullupsarerequiredduringprogramverification.Port1Port1isan8-bitbidirectionalI/Oportwithinternalpullups.ThePort1outputbufferscansink/sourcefourTTLinputs.When1sarewrittentoPort1pins，theyarepulledhighbytheinternalpullupsandcanbeusedasinputs.Asinputs，Port1pinsthatareexternallybeingpulledlowwillsourcecurrent(IIL)becauseoftheinternalpullups.Inaddition，P1.0andP1.1canbeconfiguredtobethetimer/counter2externalcountinput(P1.0/T2)andthetimer/counter2triggerinput(P1.1/T2EX)，respectively，Port1alsoreceivesthelow-orderaddressbytesduringFlashprogrammingandverificationPort2Port2isan8-bitbidirectionalI/Oportwithinternalpullups.ThePort2outputbufferscansink/sourcefourTTLinputs.When1sarewrittentoPort2pins，theyarepulledhighbytheinternalpullupsandcanbeusedasinputs.Port2emitsthehigh-orderaddressbyteduringfetchesfromexternalprogrammemoryandduringaccessestoexternaldatamemorythatuse16-bitaddresses(MOVX@DPTR).Inthisapplication，Port2usesstronginternalpull-upswhenemitting1s.Duringaccessestoexternaldatamemorythatuse8-bitaddresses(MOVX@RI)，Port2emitsthecontentsoftheP2SpecialFunctionRegister.Port2alsoreceivesthehigh-orderaddressbitsandsomecontrolsignalsduringFlashprogrammingandverification.Port3Port3isan8-bitbidirectionalI/Oportwithinternalpullups.ThePort3outputbufferscansink/sourcefourTTLinputs.When1sarewrittentoPort3pins，theyarepulledhighbytheinternalpullupsandcanbeusedasinputs.Asinputs，Port3pinsthatareexternallybeingpulledlowwillsourcecurrent(IIL)becauseofthepullups.Port3alsoservesthefunctionsofvariousspecialfeaturesoftheSTC89C52，asshowninthefollowingtable.Port3alsoreceivessomecontrolsignalsforFlashprogrammingandverification.RSTResetinput.Ahighonthispinfortwomachinecycleswhiletheoscillatorisrunningresetsthedevice.ThispindrivesHighfor96oscillatorperiodsaftertheWatchdogtimesout.TheDISRTObitinSFRAUXR(address8EH)canbeusedtodisablethisfeature.InthedefaultstateofbitDISRTO，theRESETHIGHoutfeatureisenabled.ALE/PROGAddressLatchEnable(ALE)isanoutputpulseforlatchingthelowbyteoftheaddressduringaccessestoexternalmemory.Thispinisalsotheprogrampulseinput(PROG)duringFlashprogramming.Innormaloperation，ALEisemittedataconstantrateof1/6theoscillatorfrequencyandmaybeusedforexternaltimingorclockingpurposes.Ifdesired，ALEoperationcanbedisabledbysettingbit0ofSFRlocation8EH.Withthebitset，ALEisactiveonlyduringaMOVXorMOVCinstruction.Otherwise，thepinisweaklypulledhigh.SettingtheALE-disablebithasnoeffectifthemicrocontrollerisinexternalexecutionmode.PSENProgramStoreEnable(PSEN)isthereadstrobetoexternalprogrammemory.WhentheSTC89C52isexecutingcodefromexternalprogrammemory，PSENisactivatedtwiceeachmachinecycle，exceptthattwoPSENactivationsareskippedduringeachaccesstoexternaldatamemory.EA/VPPExternalAccessEnable.EAmustbestrappedtoGNDinordertoenablethedevicetofetchcodefromexternalprogrammemorylocationsstartingat0000HuptoFFFFH.Note，however，thatiflockbit1isprogrammed，EAwillbeinternallylatchedonreset.EAshouldbestrappedtoVCCforinternalprogramexecutions.Thispinalsoreceivesthe12-voltprogrammingenablevoltage(VPP)duringFlashprogramming.XTAL1Inputtotheinvertingoscillatoramplifierandinputtotheinternalclockoperatingcircuit.XTAL2Outputfromtheinvertingoscillatoramplifier.译文：STC89C52数据手册功能特性描述STC89C52是一种低功耗、高性能CMOS8位微控制器，具有8K在系统可编程Flash存储器。使用高密度非易失性存储器技术制造，与工业80C51产品指令和引脚完全兼容。片上Flash允许程序存储器在系统可编程，亦适于常规编程器。在单芯片上，拥有灵巧的8位CPU和在系统可编程Flash，使得STC89C52为众多嵌入式控制应用系统提供高灵活、超有效的解决方案。 STC89C52具有以下标准功能；8k字节Flash，256字节RAM，32位I/O口线，看门狗定时器，2个数据指针，三个16位定时器/计数器，一个6向量2级中断结构，全双工串行口，片内晶振及时钟电路。另外，STC89C52可降至0Hz静态逻辑操作，支持2种软件可选择节电模式。空闲模式下，CPU停止工作，允许RAM、定时器/计数器、串口、中断继续工作。掉电保护方式下，RAM内容被保存，振荡器被冻结，单片机一切工作停止，直到下一个中断或硬件复位为止。VCC:电源GND:地P0口：P0口是一个8位漏极开路的双向I/O口。作为输出口，每位能驱动8个TTL逻辑电平。对P0端口写“1”时，引脚用作高阻抗输入。当访问外部程序和数据存储器时，P0口也被作为低8位地址/数据复用。在这种模式下，P0具有内部上拉电阻。在flash编程时，P0口也用来接收指令字节；在程序校验时，输出指令字节。程序校验时，需要外部上拉电阻。P1口：P1口是一个具有内部上拉电阻的8位双向I/O口，p1输出缓冲器能驱动4个TTL逻辑电平。对P1端口写“1”时，内部上拉电阻把端口拉高，此时可以作为输入口使用。作为输入使用时，被外部拉低的引脚由于内部电阻的原因，将输出电流（IIL）。此外，P1.0和P1.2分别作定时器/计数器2的外部计数输入（P1.0/T2）和时器/计数器2的触发输入（P1.1/T2EX），在flash编程和校验时，P1口接收低8位地址字节。P2口：P2口是一个具有内部上拉电阻的8位双向I/O口，P2输出缓冲器能驱动4个TTL逻辑电平。对P2端口写“1”时，内部上拉电阻把端口拉高，此时可以作为输入口使用。作为输入使用时，被外部拉低的引脚由于内部电阻的原因，将输出电流（IIL）。在访问外部程序存储器或用16位地址读取外部数据存储器（例如执行MOVX@DPTR）时，P2口送出高八位地址。在这种应用中，P2口使用很强的内部上拉发送1。在使用8位地址（如MOVX@RI）访问外部数据存储器时，P2口输出P2锁存器的内容。在flash编程和校验时，P2口也接收高8位地址字节和一些控制信号。P3口：P3口是一个具有内部上拉电阻的8位双向I/O口，P2输出缓冲器能驱动4个TTL逻辑电平。对P3端口写“1”时，内部上拉电阻把端口拉高，此时可以作为输入口使用。作为输入使用时，被外部拉低的引脚由于内部电阻的原因，将输出电流（IIL）。P3口亦作为STC89C52特殊功能（第二功能）使用，如下表所示。在flash编程和校验时，P3口也接收一些控制信号RST:复位输入。晶振工作时，RST脚持续2个机器周期高电平将使单片机复位。看门狗计时完成后，RST脚输出96个晶振周期的高电平。特殊寄存器AUXR(地址8EH)上的DISRTO位可以使此功能无效。DISRTO默认状态下，复位高电平有效。ALE/PROG：地址锁存控制信号（ALE）是访问外部程序存储器时，锁存低8位地址的输出脉冲。在flash编程时，此引脚（PROG）也用作编程输入脉冲。在一般情况下，ALE以晶振六分之一的固定频率输出脉冲，可用来作为外部定时器或时钟使用。然而，特别强调，在每次访问外部数据存储器时，ALE脉冲将会跳过。如果需要，通过将地址为8EH的SFR的第0位置“1”，ALE操作将无效。这一位置“1”，ALE仅在执行MOVX或MOVC指令时有效。否则，ALE将被微弱拉高。这个ALE使能标志位（地址为8EH的SFR的第0位）的设置对微控制器处于外部执行模式下无效。PSEN:外部程序存储器选通信号（PSEN）是外部程序存储器选通信号。当STC89C52从外部程序存储器执行外部代码时，PSEN在每个机器周期被激活两次，而在访问外部数据存储器时，PSEN将不被激活。EA/VPP:访问外部程序存储器控制信号。为使能从0000H到FFFFH的外部程序存储器读取指令，EA必须接GND。为了执行内部程序指令，EA应该接VCC。在flash编程期间，EA也接收12伏VPP电压。XTAL1:振荡器反相放大器和内部时钟发生电路的输入端。XTAL2:振荡器反相放大器的输出端。附录ATwinScrewExtrusionProcessingofEnergeticMaterialsABSTRACTThecontinuousprocessingofvariousenergeticformulationsisachallengethatrequirestheaprioritycharacterizationoftherheologicalbehavioroftheenerge-ticformulation,mathematicalmodelingoftheprocess,agoodunderstandingofthestructuredevelopmentaspectsandwaysofverifyingandcharacterizationofmicrostructuraldistributionsofenergeticgrains.Thesestepsfacilitatethegener-ationofadetailedunderstandingoftheflowanddeformationbehaviorandthethermo-mechanicalhistorythattheenergeticmaterialwillexperienceinthecontinuousprocessor.Suchwork,donepriortotheactualcontinuousprocessingofthelivematerials,eliminatesorminimizesthesubsequentriskassociatedwiththeprecarioustrialanderrorproceduresandexperimentalstudiesthatareprevalentinotherindustries~However,thedeterminationofthephysical,rheo-logicalandprocessabilitycharacteristicsofenergeticformulationsundervariousrelevantsetsofoperatingconditionsoftheextrusionprocess,thedevelopment,thefabricationandtheinstallationofinstrumentationforthecharacterizationofspecificmaterialproperties,thedataanalysisandthedeterminationofmaterialparameters,andthemathematicalmodelingofthethermo-mechanicalhistoryoftheenergeticformulationsintheextruderandthediearenotstraightforward.Thechallengesincludetheslipatthewalloftheviscoplasticsuspensions,possi-blesegregationofthebinderandthemigrationoftheparticlesinthetransversetoflowdirection,theimportantroleplayedbyair,theformationofflowinsta-bilitiesandassociatedsurfaceandbulkdistortionsofextrudates,theformationofhotspots,theimportantroleplayedbythedistributiveanddispersivemixingoftheingredientsasaffectedbythedeformationhistoryandthespecificenergyinputintheextruder.Thequantitativecharacterizationsofthedegreeofmixed-nessoflivepropellantsandexplosivesandtheparticlesizeandthedefectdens-itydistributionsofthecrystallineparticlesoftheenergeticmaterialsarealsonecessarytolinktheprocessinghistoryintheextrudertothemechanicalandburnratepropertiesoftheprocessedenergeticgrains.Inthispapersomeofthesechallengesarereviewedtocontributetowardstheimprovedsafetyofthetwinscrewextrusionprocessandbettercontrolofthequalityoftheenergeticgrams.Keywords:Extrusion,energetics,twinscrew,continuousprocessingI.INTRODUCTION:VariousGovernmentorganizationsanddefensecontractorsareengagedinthedevelopmentofadvancedenergeticcompositionsforuseinawidevarietyofapplications.Manyoftheseformulationsareintendedtobeprocessedviacontinuousprocessingtechniques,mostcommonlythefullyintermeshingco-rotatingtwinscrewextrusionprocess.Continuousprocessingallowsbettercont-rolofthemicrostructureandhencetheconsistencyoftheenergeticproductincomparisontobatchprocesses.Theprincipalfactoristhesignificantlygreatersurfacetovolumeratioofthecontinuousprocessorincomparisontothebatchprocessor.However,theenergeticmaterialsinvolveverysensitiveingredients,theprocessabilityofwhichinasuspensionisalwaysprecariousandrequirestrictexposurelimitsintemperature,residencetimeandstress.Furthermore,thescaleupoftheprocessingoperationisalsonotstraightforwardduetotherheologicalbehaviorofthecompositionsandtheprocessabilityandthephysicalpropertiesoftheenergeticformulationsbeingprincipallyaffectedbytheveryhighdegreeofsolidfilloftheformulations,whichbydesignneedstoapproachthemaximumpackingfractionofthesolidphase.Themathematicalmodelingtechniquesforcontinuousprocessingneedtotakeintoconsiderationtheirextremelyhighdegreeoffillwhichimpartsvarioussolidlikecharacteristicstotheenergeticformulationsincludingthedevelopmentofviscoplasticityandwallslipoverandabovevariousphenomenaspecifictohighlyfilledformulations,includingtheinterlockingoftheparticles,migration,ofthebinderinthedirectionofthepressuregradient,andtheextensiverolesplayedbytheentrainedairetc.Inthefollowingasummaryofwhatwehavelearnedisreviewedandtypicalresultsarepresented.II.RHEOLOGICALBEHAVIORTherheologicalbehaviorandprocessabilityofdilutetoconcentratedsuspend-sionshavebeenthesubjectofnumerousinvestigations.Informationonthedependenceoftheshearviscositymaterialfunctiononthefillercontent,particlesize,particlesizedistribution,particleshapeandorientationintheflowfieldaresummarizedinvariousreviews(1-7).Untilthe1980'sinvestigationsoftheflowanddeformationbehaviorofconcentratedsuspensionshavebeenrestrictedtosolidconcentrations,whicharebelowsixtyfourpercentbyvolume.Themajor-ityofthesestudieshaveutilizedtheCouetteflow(8-11).TheCouetteflowinvolvesthemigrationofthesolidparticlesandtheresultingconcentrationgradients(12,13).Suspensionswhicharefilledatsolidloadinglevelsclosetothemaximumpackingtractionottheirsolidphase,presentspecialchallengesmthecharacteri-zationoftheirrheologicalbehaviorandmathematicalanalysesoftheircontin-uousprocessability.AsshownbyKalyonandcoworkers,thebehaviorofsuchmaterialsaresubjecttowallslipinbothrotationalandcapillaryrheometers(14,15)andflowinstabilitiesindieflowsassociatedwithmatformationandfiltra-tionofthebinder(16,17).Suchsuspensionscanexhibittheologicaldilatancywithanintimaterelationshiptoslipatthewallduringflow(18).Sincetheconcentrationofsolidsapproachesthemaximumpackingfraction,therheologicalbehaviorandtheprocessabilityofhighlyfilledsuspensionsareverysensitivetotheamountanddistributionofairentrainedduringprocessing(19).Airentrainmentisrelatedtothegeometryandoperatingconditionsempl-oyedduringprocessing,especiallyonthedegreeoffilldistributioninthecontinuousprocessor(20).Inthefollowingvariousimportantfactorsaffectingthecontinuousprocessingandmanufacturabilityofpropellantsandexplosiveswillbediscussed.Thesefactorsincludetheirflowanddeformationbehaviorinvolvingwallslip,flowinstabilities,airentrainmenteffects,andcontinuousprocessing.Thistraditionaltechniqueofsystematicallychangingthesurfacetovolumeratioofthesuspensionduringrheologicalcharacterizationtoindirectlydeter-minetheslipvelocityisverylaborintensive.Asanalternativetechniquefordeterminationofwallslipvelocitiesinparalleldisktorsionalflows,theflowvisualizationtechniqueillustratedinFigure1canbeused.Thistechniqueallowsthedeterminationoftheslipvelocityandthetruedeformationrateofthesusp-endsiondirectly(15).Thedeformationofthemarkerlineisopticallyrecordedasafunctionoftimeasthediskatthetoprotates.Computerizedimageanalysisoftherecordedimagesgeneratesthevelocityofthesuspensionfoundadjacenttothewall,Vsafunctionoftime.Theslipvelocityatthewall,U~,canthenbedeterminedfrom:=vt-vw(1)whereVwisthewallvelocity.Wallslipbehaviorisgenerallytimedependent(29).Withincreasingdurationofdeformation,thedeformationrateofthesuspensiondecreases,whiletheshearstressandthewallslipvelocityincrease.Undertypicalconditionsthesteadystatebehaviorisachievedatwhichthetruedeformationratecanonlybeabout1/5thoftheimposedapparentshearrate.Theramificationsincludethetime-dependenceofthestart-upflowinextrusion,andthedecreasingoftheshearratesandtotalstainswhichcanbeintroducedintothesuspensionintheextruderupontheonsetofslip.Thetypicalsteady-stateslipvelocityatthewallversuswallshearstressbehav-eiorofenergeticsuspensionsfollowstheNavier'sslipconditionshowninEqu-ation2.Thewallslipvelocity,U,,versuswallshearstress,r~e,datacanbefittedby:U=(2)where,8istheNavier'sslipcoefficient,whichforvariousmaterialsalsodependsonthenatureofthewallsoftherheometer(21,22).FortheASRMsolidrocketfuelsimulant(asuspensionwith76.5solids)thevaluesoftheNavier'sslipcoefficient,13wasdeterminedtobe7.4x10-4mm/Pa.sattypicalprocessingconditions(14,15).Thetrueshearviscositybehaviorofconcentratedsuspensionscanthenbedeter-mineduponthecorrectionsforwallslip.Withincreasingcapillarydiameter,atconstantcapillarylength/diameterratio,theshearstressincreases.Forexampleforsomesolidrocketfuelsthedataindicatethatthesuspensionflowsasaplugaboveawallshearstressvalue,whereasforsomeotherenergeticsuspensions,thesuspensionsexhibitplugflowatwallshearstressvalueswhicharesmallerthanacriticalshearstressvalue.Insummary,variousnovelrheologicalcharact-erizationtechniquesneedtobeusedtocharacterizewallslipandthenusethedataaspartofthemathematicalsimulationeffort.Applicationsofthesetechni-quesallowdatatobecorrectedtogeneratethetruerheologyandalsoprovidetheinterfaceconditioni.e.,slipvelocityversusstressinextrusionanddieflows.FlowInstabilitiesDuringProcessingandFlowofpropellantsandexplosivesPressuredrivenflowsofpropellantsandexplosivescangiverisetoflowinsta-bilitiesassociatedwiththetime-periodicformationofmatsofsolidsinconverg-ingflowsandthefiltrationofthebinder.Suchtime-dependentdemixingoftheingredientsoftheformulationofhighlyfilledsuspensionsdoesafectthequalityofthedegreeofmixingofthesuspensionandhenceitsultimateproperties.Itlsorendersthecontinuousprocessingoperationunstableandposesasafetyhreatincontinuousprocessingofenergeticsuspensions(16).Theextrudatemergingfromthediecanberesin-richorpoorinacyclicfashion.Atrelativelyighscrewspeedsthepressurebeforethediecanrapidlyasaffectedbydramaticemixingandpulverizationoftheenergeticfillerinthecontinuousprocessor.Capillaryflowexperimentscanbeusedtoprovideabetterunderstandingoftheflowinstabilitiesofconcentratedsuspensionsoccurringincontinuousproce-ssingoperations(16,31).Underunstableflowconditions,theaveragepressurenecessarytoextrudethesuspensiongrowsunboundedwithtime,withgenerallyincreasingamplitudeofoscillations.Thetimeperiodicoscillationsinextrusionpressurearerelatedtothetimeperiodicmechanismofformationofamatofsolidsatthecapillaryordieanditsbreak-up.Thisoccursconcomitantwiththefiltrationofthebinder.Duringthemostsevereconditionsoffiltration,thebind-er,containingvisibleairpockets,emergesfromthecapillarytoformdropsthatmomentarilyclingtothebottomofthedie.Theapparentshearraterangeinwhichtheflowofthehighlyfilledsuspensionisstablecanbebroadenedbyincreasingtheviscosityofthematrix(lowertemp-erature),increasingtheshearstressatthewall,andthroughtheuseofdieswithreaterdiameters.Fordieflowofanenergeticsuspensionwherethesuspensionlowslikeaplugwithashearstressdependentslipvelocityatthewall,U,,thelowbecomesunstablewhenthefiltrationvelocityVmbecomesgreaterthanthelipvelocityoftheplug(I6,31).Thecriticalapparentshearratevalueforeachieatwhichtheflowinstabilitiesareon-setcanbepredictedonthebasisoftheomparisonoffiltrationandwallsliprates(16).Obviouslyintheprocessingofpropellantsandexplosivesthefiltrationofthematrixandthustheunstableregionshouldbeavoided.Otherwise,theadditionallossofthebinder,duetoaxialmigrationatsolidloadinglevelsthatareveryclosetothemaximumpackingfraction,willrenderthesuspensionunprocess-able.Theunstableregioninconvergingflowscanbeavoidedbytheproperselectionoftheproductionrateandthegeometryofthechannelthroughwhichthesuspensionisflowing.ForexampletheexperimentaldataandtheresultsofthetheoreticalapproachusedduringtheanalysisofthepropellantusedintheAdvancedShuttleprogram(ASRM)suggestedthatthecriticalapparentshearrate,belowwhichflowinstabilitiesprevail,decreaseswithincreasingchanneldiameter.Themigrationoftheparticlesinthetransversetotheflowdirectionneedstobeassessedalso(12,13,32).AirEntrainmentEffectsSincetheformulationsofpropellantsandexplosivesinvolvevolumefractionsofsolidswhichapproachthemaximumpackingfractionofthesolidphase,theincorporationofevensmallconcentrationsofair,makesasignificantdifferenceintherheologicalbehaviorandhencetheprocessabilityofhighlyfilledsuspend-ons(19,33).Ingeneralthesuspensionsamplesprocessedwithoutvacuumcanontainanadditionalfewpercentbyvolumeairunderambientconditions.Thehearviscosityofthesuspensiondecreasesandwallslipvelocityvaluesincreaseiththeincorporationofairintothesuspension.Theairentrainedintoannergeticsuspensionsamplecanbestudiedusingx-rayradioscopyandmagn-ticresonanceimagingmicrographs(19).Theamountofairentrainedintotheuspensionincreasesatpartiallyfullregionsinthecontinuousprocessorinomparisontosuspensionsamplescollectedfromcompletelyfullsectionsofthecontinuousprocessor(20).Forexample,thedensityvaluesofsamplescollectedfromthereverselyconfiguredscrewsectionsofatwinscrewextruder(whichnecessitatecompletelyfullmixingvolume)aregreaterthanthoseofthesamplescollectedfromthepartiallyfullsectionsofthesameextruderi.e.,atforwardlyconfiguredscrewsections(20).Theairentrainedintothesuspensionalsoaffectsthedevelopmentandnatureofthesliplayer(binderrichregionfoundadjacenttothewall)ofthesuspensionduringdieflows.Undermoderatediepressures,pocketsofairclingtothewallmomentarilyandarespreadouttobelaterdragged-onbythebulkofthesuspension.Thewallofthedieappearstobecoveredpartiallywithfilmsofairduringextrusion,withtheairfilmcontinuouslybeingremovedandreplenished(Figure3).MICROSTRUCTURALANALYSISOFPROPELLANTSANDEXPLOSIVESDEGREEOFMIXINGBackgroundOneofthemostchallengingaspectsofanymixingoperation,wheretwoormoreidentifiablecomponentsarebroughttogether,isthecharacterizationofthestateofthemixturei.e.,thedegreeofmixingorthe"goodness"ofmixing.Intheon-diffusivemixingofaviscouspolymericbinderwithsolidcomponents,theompletedescriptionofthestateofthemixturewouldrequirethespecificationfthesizes,shapes,orientationsandthepositionsoftheultimateparticlesofthecomponents.Ifthematerialsofinterestareopaqueoriftransparentbarrelsectionscannotbebuilt,themechanismsofmixingcanbestudiedthrough"post-mortem"anal-ysis.Inthistechnique,generallyadistinguishabletracerisaddedintoamixerinasteporpulsefashion.Uponcertaindurationofmixing,themixtureissystema-ticallyremovedfromthemixerandsectionedtoallowtheinvestigationofdistri-butiveanddispersivemixingaspects.Kalyonandco-worke