简介:摘要:随着飞行器机载系统综合化水平的不断提高,对数据总线的速率、可靠性、确定性的要求也越来越高,Mil-1553b等传统数据总线已不能满足要求,Mil-1394b采用SAE AS5643标准,是以IEEE1394b为基础,面向军用和飞行器应用进行扩展和约束来进行增强,以达到满足安全关键/任务关键系统所需的鲁棒性和确定性的目的,适用于作为安全关键的航空总线等高可靠场合的应用。Mil-1394b总线在国内外军事及航空航天领域已经相继得到使用,本文基于1394b总线的容错机制对几种典型的总线拓扑结构进行可靠性研究,对1394b总线的应用具有一定的理论意义和实用价值。
简介:【摘 要】针对基于MIL-STD-1553B总线的机载网络系统,出现信息传输异常现象,现从设计原理上进行详细的分析,并提出排查方案,为机载MIL-STD-1553B总线信息传输异常排查提供借鉴。
简介:BMIL-53(Fe)/MWCNTshybridmaterialwaspreparedviathesolvethermalsynthesismethod.TheresultingsampleswerecharacterizedbyX-raydiffraction,FT-IRspectroscopy,scanningelectronmicroscopy,UV-Visabsorptionspectroscopy,theBrunauer-Emmet-Tellermethod,andphotoluminescencespectroscopy.TheresultshowedthattheintroductionofmultiwalledcarbonnanotubestotheMIL-53(Fe)canincreasethesurfaceareaofthecomposites,suppresstherecombinationofphotogeneratedelectron-holepairsandpromotetheelectrontransferprocess.ThehybridmaterialshowedoptimalphotocatalyticperformanceinthedegradationofRhodamineBundertheirradiationofultravioletandnaturallight.
简介:摘要本文介绍了基于1394B数据总线远程更新TMS320F2812片上FLASH的方法,该方法可以推广到RS-422A,ARINC429等航空常用总线,在不更改硬件设计的情况下,从上位机下载数据即可实现软件升级,为类似产品的设计提供参考。
简介:Co(II)-salenwasencapsulatedinMIL-100(Cr)metalorganicframeworkby"shipinabottle"tosynthesizeanewelectrocatalyst,Cosalen@MIL-100(Cr).ThematerialwascharacterizedbyXRD,FT-IR,UV-VisandN2-adsorption.TheCosalen@MIL-100(Cr)modifiedglassycarbonelectrodeexhibitsawell-definedreductionpeakatthepotentialof–0.21Vtowardtheoxygenreductionreaction(ORR)bycyclicvoltammetry(CV)inpH=6.84phosphatebuffer.Almost400mVpositiveshiftofpotentialatCosalen@MIL-100(Cr)modifiedelectrodeforORRcomparedwiththatatbareglassycarbon,indicatesthatCosalen@MIL-100(Cr)possessesexcellentelectrocatalyticactivity.ThetransferrednumberofelectronsforORRwasdeterminedbychronocoulometry.TheresultsuggeststhattheintroductionofCo(II)-salencomplexintoMOFincreasestheelectrocatalyticactivityviaafour-electronreductionpathway.Furthermore,thiselectrocatalystexhibitsgoodstabilityandreproducibility.
简介:目的检测乙型病毒性肝炎病人外周血T细胞亚群和膜白介素-2受体(mIL-2R)表达水平并探讨其在乙肝发病机制中的作用.方法采用生物素-链霉亲和素法对188例乙肝病人外周血单个核细胞(PBMC)进行T细胞亚群及植物血凝素(PHA)诱导前后mIL-2R水平测定.结果乙肝病人T淋巴细胞亚群中CD3+、CD4+降低,CD8+升高,CD4+/CD8+比值降低,外周血单个核细胞mIL-2R表达水平在PHA诱导前后均降低,与正常对照相比,差异有显著意义(P<0.01);另外,乙肝病人PBMC中HBV-DNA(+)病人与PBMC内HBV-DNA(-)病人相比,mIL-2R表达水平亦存在较大差异(P<0.01).结论乙肝病人体内存在明显的细胞免疫功能紊乱,T细胞活化障碍,并与肝病的慢性化相关.
简介:Variousmesoporouschromiaaluminacatalystswerepreparedbyfivedifferentmethodsbasedonametal-organicframeworkMIL-101andtheircatalyticperformancesoverisobutanedehydrogenationwereinvestigated.ThehighlydispersedchromiumspecieswereproducedoncatalystKCrAl-I1withlargestspecificsurfaceareaof198m2g-1preparedwithaluminiumisopropoxide(Al(i-OC3H7)3)byultrasonicimpregnationmethod.However,thecatalystKCrAl-I2synthesizedbystirringimpregnationpossessedcrystallineα-Cr2O3phase,whichwaspoorlydispersed.TwotypesofCr-richandAl-richCrxAl2-xO3solidsolutions,designatedasCrAl-IandCrAl-IIphase,wereformedoverthecatalystsKCrAl-I3(preparedbyAl(i-OC3H7)3withnitricacidregulation),KCrAl-C4(preparedbyaluminiumchloridehexahydrate)andKCrAl-N5(preparedbyaluminiumnitratenonahydrate).CatalyticevaluationresultsrevealedthatKCrAl-I1exhibitedthehighisobutaneconversionduetoitshighlydispersedchromiumspecies.However,KCrAl-I3,KCrAl-C4andKCrAl-N5showedthehigherisobuteneselectivity(95.2%-96.4%)onaccountoftheformationofchromiaaluminasolidsolutionsinthecatalysts.Moreover,thesolidsolutionoverthechromiaaluminacatalystscouldgreatlysuppressthecokeformation.
简介:Inthiswork,aseriesofMIL-101-SO3H(x)polymericmaterialswerepreparedandfurtherusedforthefirsttimeasefficientheterogeneouscatalystsfortheconversionoffructose-basedcarbohydratesinto5-ethoxymethylfurfural(EMF)inarenewablemixedsolventsystemconsistingofethanolandtetrahydrofuran(THF).Theinfluenceof–SO3HcontentontheacidityaswellasonthecatalyticactivityoftheporouscoordinationpolymersinEMFproductionwasalsostudied.HighEMFyieldsof67.7%and54.2%couldbesuccessivelyobtainedfromfructoseandinulininthepresenceofMIL-101-SO3H(100)at130°Cfor15h.Thecatalystcouldbereusedforfivetimeswithoutsignificantlossofitsactivityandtherecoveryprocesswasfacileandsimple.Thisworkprovidesanewplatformbyapplicationofporouscoordinationpolymers(PCPs)fortheproductionofthepotentialliquidfuelmoleculeEMFfrombiomassinasustainablesolventsystem.