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简介：AbstractParkinson disease (PD) is the second-most common neurodegenerative disorder. Its main pathological mechanism is the selective degeneration and deletion of dopaminergic neurons in the dense part of the substantia nigra and the damage of dopaminergic neurons caused by the abnormal deposition of a Lewy body, leading to a decreased dopamine level. Positron emission computed tomography (PET)/single photon emission computed tomography (SPECT) is a molecular imaging technology that can directly or indirectly reflect changes in molecular levels by using a specific tracer. With the research and development on the tracers of related enzymes for labeling dopamine transporter and dopamine receptor and for being involved in dopamine formation, this imaging technology has been applied to all aspects of PD research. It not only contributes to clinical work but also provides an important theoretical basis for exploring the pathological mechanism of PD at a molecular level. Therefore, this review discusses the application value of PET/SPECT in PD in terms of early diagnosis, disease severity evaluation, clinical manifestations, differential diagnosis, and pathological mechanism.

简介：ThepurposeofthisstudyismerelytoreviewthecurrentsituationinthedesigningandimplementationoftheemissiontradingprogramsinEurope.Historicaldatashowthatalthoughthereisaseriesofshortcomingsintheircurrentfunctioning,employingsuchinstrumentsforGHGreductionpolicymakingisstronglyexpectedtobeefficientandeffective.TheEuropeanUnionEmissionTradingScheme(EUETS),CleanDevelopmentMechanism(CDM)andJointImplementation(JI)arejustafewexamplesoftheambitiousEUinitiativethatheavilyreliesonsuchinstruments.WedwellontheiroperationsandachievementsbyfarandallthecontentinthisarticleisexpectedtoconvincetheChinesegovernmentandregionalpublicauthoritiestotakepositiveactionsandattitudesinpromotingtheseinstruments.

简介：ExperimentalandtheoreticalinvestigationofpromptnitrogenoxidesemissioninflameofdifferentgaseousfuelswerecarriedoutwithpurposeofminimizingtotalNOxyield.Theeffectofthefollowingfactorswasdetermined:airexcessfrom0.3to1.1,flametemperature,heatingflamerate,fuelcontent,Itwasfoundthat,ifairexcesswaslessthan0.65,somepromptNOxconvertedtoN2inconsequenceofreactingwithhydrocarbonradicals.

简介：AccordingtothenewsfromChinaDaily,Chinaislikelytoagreetoaquantifiedtargettolimititsgreenhousegasemissionsafter2020.ButthisdependsontheoutcomeofclimatechangenegotiationsandChina’slevelofdevelopmentbythattime.Thisisthefirsttimethat

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简介：InordertoobtainhigheremissionperformancethanthatofatraditionalM-typecathode,wehavedevelopedanewtypeimpregnateddispensercathode.Thenewcathodeisimpregnatedwithanewactivesubstancewithmolarratioof26BaO·29SrO·8Sc2O3·7CaO·Al2O3.Thispaperintroducestheemissionperformance,surfaceactivematerial,andworkfunctionofthenewcathode.At1100℃B,theDCcurrentdensityandpulsecurrentdensityare30.6±1.0A/cm2and171.6±2.8A/cm2,respectively,2.1and5.4timesofthatofanM-typecathode.Theworkfunctionofthenewcathodeis1.668±0.002eV.HighconcentrationO-Al-Sc-Sr-BaandO-Al-Sc-Baarefoundintheporesandatporeedges,respectively.Bycomparingtheemissionperformancesandsurfacecharacteristicsofas-polishedandas-cleanedcathodes,itisproposedthat,theemissionaroundporeendsformsthemajorpartofthetotalemissionforthenewcathodes.

简介：Sinteringpottestswithhotairwereconducted.Airwasheatedbyusingaresistancefurnacetosimulateheatrecoveryfromexhaustgasfromthesinteringplant.Theeffectsoftheprocessparameters,suchastemperatureofhotair,oxygenenrichment,cokeconsumptionandbeddepth,onqualityofproducts,energyconsumptionanddioxinemissionwereinvestigated.Goodresultswereobtainedunderthefollowingconditions:2001hotair,nooxygenenrichment,limewithhighCaO,thinnerbedandadditionofaccelerant.

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简介：为压电的陶器的排放变换器匹配的Butterworth上的一条定理被介绍并且证明。宽带匹配的复杂问题由于定理的明确的公式被改变到简单的算术的。当力量获得接近1时，它在一个例子被显示出在匹配以后，变换器的带宽显著地增加。

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简介：Sincethesimilarityinsizedistributionofearthquakesandacousticemissions(AE)wasfoundinthe1960s,manylaboratorystudieshavebeenmotivatedbytheneedtoprovidetoolsforthepredictionofminingfailuresandnaturalearthquakes.Thispaperaims,ontheonehand,todrawanoutlineoflaboratoryAEstudiesinthelast50years,whichhaveaddressedseismologicalproblems.TopicsincludethepowerlawsinwhichthesimilaritybetweenAEsandearthquakesisinvolvedandprogressthathasbeenmadeinAEtechnologyandlaboratoryAEstudy.Ontheotherhand,thisstudywillhighlightsomekeyissuesintensivelydiscussed,especiallyinthelastthreedecades,suchasaspectsrelatedtothepre-failuredamageevolution,faultnucleationandgrowthinbrittlerocksanddiscussfactorsgoverningtheseprocesses.

简介：Theacousticemission(AE)featuresinrockfracturearesimulatednumericallywithdiscreteelementmodel(DEM).Thespecimenisconstructedbyusingsphericalparticlesbondedviatheparallelbondmodel.Asaresultoftheheterogeneityinrockspecimen,thefailurecriterionofbondedparticleiscoupledbytheshearandtensilestrengths,whichfollowanormalprobabilitydistribution.TheKaisereffectissimulatedinthefractureprocess,foracubicrockspecimenunderuniaxialcompressionwithaconstantrate.TheAEnumberisestimatedwithbreakagesofbondedparticlesusingapairofparameters,inthetemporalandspatialscale,respectively.ItisfoundthattheAEnumbersandtheelasticenergyreleasecurvescoincide.TherangefortheKaisereffectfromtheAEnumberandtheelasticenergyreleasearethesame.Furthermore,thefrequency-magnituderelationoftheAEnumbershowsthatthevalueofBdeterminedwithDEMisconsistentwiththeexperimentaldata.

简介：Agriculturalgreenhousegasaccountsforalargeproportionofglobalanthropogenicgreenhousegasemission.ThepapercarriedonacalculationongreenhousegasemissionofChinaagriculturalgreenhousegasemission,andanalyzedinfluencingfactorsofagriculturegreenhousegasemissionwhichhasimportantsignificanceforthedevelopmentofChineseandgloballowcarbonagriculture.ThispapercalculatedtheemissionofCH4,N2OandCO2inChinafromtheyearof1993to2011,andanalyzedtheinfluencefactors.TheresultsshowedthatCH4emissionwasbasicallystable,whichmaintainedat2000tons.AnimalhusbandryCH4emissionwasthelargestcontributorofagriculturalsourceCH4emission.Takingtheyearof2011asanexample,whichaccountedfor53.08%;N2Oemissionwasincreasedfrom93.21tonsof1993to120.51milliontonsof2011,andtheaverageannualgrowthratewas1.63%.PlantingwasthemaincontributortoN2Oemission.Takingtheyearof2011asanexample,whichaccountedfor54.36%ofthetotalemission,landN2Oemissionwasthemost,andthericefieldwasfollowed;agriculturalsourceCO2emissionincreasedfrom15626.98to31258.10milliontons,andtheaverageannualgrowthratewas5.56%;fertilizersourcewasthelargestsourceofcarbon,in2011,forexample,fertilizersourceofCO2emissionwas18731.83milliontonsaccountedfor59.93%oftheagriculturalsourceCO2emission.CH4andN2OemissionsofChinaAgricultureweremainlycausedbyanimalhusbandryandchemicalfertilizers.AndpesticidesweremajorcontributorstoCO2emissionofagriculture.Attheendofthispaper,basedontheresultsofcorrelationanalysis,thepaperproposedcountermeasuresandsuggestionsforChina’slowcarbonagriculture,anddemonstratedthesignificanceofgloballowcarbonagriculturedevelopment.

简介：追踪的正电子排放粒子(PEPT)技术广泛地在科学和工程被使用了例如，在多相的系统在运动和液体或小粒的材料的流动领域上获得详细信息在岩石裂缝，化学反应堆和食品加工器的液体；在化学反应堆，granulators，混合器，干衣机，旋转火炉和球工厂的小粒的材料的动态行为。PEPT技术获得的信息能被用来优化设计，并且评估建模，为大量工业过程系统的运作的条件工作。这种技术基于由检测对追踪放射性地标记的粒子(多达三个粒子)紧接511条keV光线从射出的正电子的歼灭产生。它因此包含一个正电子照相机，为计算tracer地点和速度的地点算法，和把技术标记的tracer。这份报纸将考察从追踪算法追踪技术的粒子，标记到他们的申请的tracer。

简介：1.ＩｎｔｒｏｄｕｃｔｉｏｎＱｕａｓａｒｓａｒｅｔｈｅｍｏｓｔｌｕｍｉｎｏｕｓｏｂｊｅｃｔｓｉｎｔｈｅｕｎｉｖｅｒｓｅａｎｄｔｈｅｈｉｇｈｅｓｔｒｅｄｓｈｉｆｔｏｂｊｅｃｔｓｗｅｃａｎｄｉｒｅｃｔｌｙｏｂｓｅｒｖｅ.Ｕｎｄｅｒｓｔａｎｄｉｎｇｔｈｅｉｒｅｍｉｓｓｉｏｎｌｉｎｅｓｈａｓａｃｏｓｍｏｌｏｇｉｃａｌｉｍｐｅｒａｔｉｖｅｓｉｎｃｅｔｈｅｉｒｓｐｅｃｔｒａｄｅｐｅｎｄｏｎｌｕｍｉｎｏｓｉｔｙ(ｔｈｅ“Ｂａｌｄｗｉｎｅｆｆｅｃｔ”;Ｂａｌｄｗｉｎ1977,Ｏｓｍｅｒｅｔａｌ.1994).Ｏｎｃｅｗｅｃａｎｄｉｒｅｃｔｌｙｍｅａｓｕｒｅｔｈｅｉｒｌｕｍｉｎｏｓｉｔｙｔｈｅｑｕａｓａｒｓｗｉｌｌｇａｕｇｅｔｈｅｅｘｐａｎｓｉｏｎｏｆｔｈｅｕｎｉｖｅｒｓｅａｔｒｅｄｓｈｉｆｔｓｚ∧5.Ａｔｔｈｅｓａｍｅｔｉｍｅ,ｔｈｅｏｒｉｇｉｎｏｆｔｈｅｃｈｅｍｉｃａｌｅｌｅｍｅｎｔｓｒｅｍａｉｎｓａｃｅｎｔｒａｌｔｈｅｍｅａｃｒｏｓｓｍｕｃｈｏｆｓｔｅｌｌａｒ,ｇａｌａｃｔｉｃ,ａｎｄｅｘｔｒａｇａｌａｃｔｉｃａｓｔｒｏｐｈｙｓｉｃｓ.Ｑｕａｓａｒｓｐｒｏｂｅｅａｒｌｙｅｐｏｃｈｓｉｎｔｈｅｆｏｒ...

简介：Inthisbriefreportweproposeasimplemodelbasedonthepropertiesofanelectriccapacitorundershort-circuitconditionsasapossiblemechanismofradioemissionsassociatedwithearthquakes.Thismodelcanbeconsideredascomplementarytoothermodelsconcerningthesameproblem.