简介：Silicaaggregateswerepreparedbybase-catalyzedhydrolysisandcondensationofalkoxidesinalcohol.Polyethyleneglycol(PEG)wasusedasorganicmodifier.ThesolswerecharacterizedusingSmallAngleX-rayScattering(SAXS)withsynchrotronradiationasX-raysource.Thestructureevolutionduringthesol-gelprocesswasdeterminedanddescribedintermsofthefractalgeometry.As-producedsilicaaggregateswerefoundtobemassfractals.Thefractldimensionsspannedtheregime2.1-2.6correspondingtomorebranchedandcompactstructures.BothRLCAandEdenmodelsdominatedthekineticgrowthunderbase-catalyzedcondition.

简介：Anewprocedurewasdevelopedforestimatingtheeffectivecollisiondiameterofanaggregatecomposedofprimaryparticlesofanysize.ThecoagulationcoefficientoftwooppositelychargedparticleswasmeasuredexperimentallyandcomparedwithclassicFuchstheory,includinganewmethodtoaccountforparticlenon-sphericity.Asecondsetofexperimentswereperformedonwell-definednanoparticleaggregatesatdifferentstagesofsintering,i.e.fromtheaggregatetothefullysinteredstage.Here,electricalmobilitywasusedtocharacterizetheparticledrag.Theaggregatesarebeingbuiltfromtwodifferentsize-fractionatednanoparticleaerosols,thenon-aggregatedparticlesarediscardedbyanelectrofilterandthentheyarepassedthroughafurnaceatconcentrationslowenoughnottoinducecoagulation.

简介：Thisworkbrieflysummarizedtherecentresearcheffortsmadeonthephaseheattransferprocessesinvolvingbiologicalaggregates,withparticularattentiononthecorrelationofaggregatestructureandstateofwaterwiththeprocessefficiency.Thephasechangeprocessesincludeboiling,drying,freezing,sintering,pyrolysis,andsupercriticalextraction,whiletheformerthreewerediscussedinsomedetail.

简介：Therelationshipbetweenpetrographicalandphysicalpropertiesoflimestone,basalt,graniteandgneisswasinvestigated.Petrographicaldatawerequantifiedfrompolishedthinsectionswithapolarisingmicroscopetodeterminethemodalcomposition.ThepropertiesofresistancetofragmentationandabrasionweredeterminedbyLosAngelesabrasiontestandcrushingtest.TheshapecharacteristicwasmeasuredbyFlakinessindextest.Theexperimentalresultsindicatethatabundanceoffinetomedium-grainedminerals(especiallyofplagioclase,quartzandfeldspar)areprime,andstrongmicrographicintergrowthtexturewithinterlockinggrainboundarieshavethegreatpositiveinfluenceonthephysicalproperties.Itisalsoindicatedthatpetrographicalpropertiesandsurfacetextureofrockscandecidethepotentialityofrocksasrawmaterialswithhighqualityonresistingfragmentationandabrasion.AnalysisofIntegrationofpetrographicaldataandmechanicalpropertiesisidealfortheselectionofaggregatesusedinasphaltconcrete.

简介：

简介：Theresultsofanexperimentalstudyoninvestigatingthepropertiesofcementitiousrenderingmortarspreparedwitharecycledfineaggregate(RA)werepresented.TheRAwasobtainedfromarecyclingplantinwhichmixeddemolitionwasteswereprocessedbymechanicalcrushing,sievingandsortingoperations.Twoseriesofrenderingmortarmixeswerepreparedwithaconstantwater/cementandaconstantaggregate/cementratiosof0.55and3respectively.Riversandandnaturalcrushedrockfinewereoriginallyusedinthetwoseriesseparately,andtheywereconsistentlyreplacedby25%,50%,75%and100%bytherecycledaggregate.Theexperimentalresultsshowedthatmechanicalproperties,suchascompressivestrength,flexuralstrengthandmodulusofelasticityofthemortarspreparedwiththeRAwerelowerthanthemortarsmadewiththenaturalaggregates.Nevertheless,thebondstrengthattheinterfacebetweenthemortarandmasonrybricksdeterminedbytheTriplettestwasfoundtobehigherforthemortarspreparedwiththeRA.

简介：

简介：TheroleoforganicmatterintheformationandstabilityofsoilaggregatesinmulberryplantationintheHang-Jia-HuPlain,northernZhejiangProvince,wasevaluatedinthisstudy.Apositivecorrelationwasfoundbetweenwater-stableaggregatecontentsandorganicmattercontentsinthemulberryplantationsoils,whichsupportedthehypothesisthatorganicmatterwasthemaincementingagentinformationofaggregates.Aclosecorrelationwasalsofoundbetweenstabilityofaggregateandorganicmattercontents.Regressionanalysisshowedthattotalnitrogencontentwasalsoanindicatorofwater-stableaggregatecontentandstability.Theaggregatesizedistributionindicatedthatthewater-stableaggregates1～0.25mmindiameterwerethemajorcomponentoftheaggregatesinthemulberryplantationsoils.Theorganicmattercontentsofaggregatesrangingfrom5to0.25mmindiameterincreasedwiththedecreaseofaggregatesizes,andtheaggregates1～0.25mmindiameterhadthemaximumorganicmattercontent.

简介：Duringthemassformationofaggregatesofmoleculesinagelatinfilmdyedwiththemixtureofchrysophe-nineandacridineyellowdyes,photo-reorientation,photo-disorientation,andphoto-orientationofthemoleculesareobserved.Basedontheseobservations,thephoto-inductionofgranularanisotropymayberealized.

简介：StructuralhealthmonitoringofRCstructuresunderseismicloadshasrecentlyattractedmuchattentionintheearthquakeengineeringresearchcommunity.Inthisstudy,apiezoceramic-baseddevicecalled'smartaggregate'wasusedforthehealthmonitoringofRCframestructuresunderearthquakeexcitations.ThreeRCmomentframesinstrumentedwithsmartaggregatesweretestedusingashaketablewithdifferentgroundexcitationintensities.Distributedpiezoceramic-basedsmartaggregateswereembeddedintheRCstructuresandusedtomonitortheirhealthconditionduringthetests.Thesensitivityandeffectivenessoftheproposedpiezoceramic-basedapproachwereinvestigatedandevaluatedbyanalyzingthemeasuredresponses.Thedisplacementductilitydemandofthestructuralmemberswascalculatedandcomparedwiththedamageindexdeterminedfromthehealthmonitoringsystem.Thecomparisonshowsthatthedamageindexiscompatiblewiththecalculatedductilitydemand.

简介：Bariumsulfateaggregateswithanaveragesizeof0.5μmweresynthesizedatpH7,directedbyethylenediaminetetraaceticacid（EDTA）anions.Theparticlemorphology,chemicalcomposition,andsizedistributionoftheBaSO4aggregateswerecharacterized.Theas-synthesizedBaSO4particlesweresphericalandcomprisedmanyinterconnectednanoballs,ofwhichthesurfacepropertieswereaffectedbytheEDTAanions.TheadsorptionofEDTAanionsreversedthechargeandweakenedthesurfacepolarityofBaSO4,instigatingtheformationofaggregatesbyaself-assemblyandtransformationprocess.TheresultingBaSO4particlesatpH9-10wereellipsoidalandfeaturedsmoothsurfaces.BasedonthezetapotentialofBaSO4,variationsinthemorphologyinducedbychangesinpHwerecloselyrelatedtotheadsorptionofmono-andmulti-valentanionsontotheelectricaldoublelayerofBaSO4.

简介：ThemullitizationofandalusitefromXinjiang,ChinaandinfluenceofaggregatesonpropertiesofaluminosilicaterefractorieswerestudiedbyXRD,SEM,EDS,DSC.Itwasfoundthatmullitizationwasobviousat1400℃,butconsiderableat1500℃.TherefractorieswithcorundumaggregateshadthehighestRULandthelowestcreeprate,butrefractorieswithbauxiteaggregateshadthelowestRULandthehighestcreeprate.

简介：Soilaggregatestability,animportantindexofthephysicalcharacteristicsofasoil,canprovideagoodindicationofasoil’serodibility,anddeservesspecialconsiderationinregionswithcoldclimate.Theobjectiveofthisstudywastostudytheeffectoffreeze-thawonsoilwater-stableaggregatesintheblacksoilregionofNortheastChina.Samplesofatypicalblacksoilintheregionwerecollectedtomeasurewater-stableaggregatesafterfreeze-thawunderdifferentconditions(i.e.,initialmoisturecontents,freezethawcyclesandfreezingtemperatures)bywet-sievingintoeightparticlesizegroups(>10,10–6,6–5,5–3,3–2,2–1,1–0.5,and0.5–0.25mm).Freeze-thawhadthemosteffectonaggregatestabilitywhenthesampleshadaninitialmoisturecontentof400gkg-1.Thewater-stableaggregatesofthefourlargerparticlesizegroups(>5,5–3,3–2,and2–1mm)reachedapeakstabilityvalue,butthoseofthetwosmallerparticlesizegroups(1–0.5and0.5–0.25mm)reachedaminimumvaluewhenthesoilmoisturecontentwas400gkg-1.Water-stableaggregatesofthefourlargerparticlesizegroupsdecreasedwhilethoseofthetwosmallerparticlesizegroupsincreasedwiththeincreaseoffreeze-thawcycles.Astemperaturesfell,thewater-stableaggregatesofthefourlargerparticlesizegroupsdecreasedwhilethoseofthetwosmallerparticlesizegroupsincreased.

简介：Fivelightweightmullitecastableswerepreparedusingthelightweightmulliteaggregate(M45A)withnarrowparticlesizedistributionandsphericalshape,mullitepowder(M45P),kyanitepowder,microsilicaandSecar71cementasrawmaterials.Afterthespecimensfiredat1100℃,1200℃and1300℃for3h,respectively,theeffectsofkyanitecontents(8%,10%,12%,14%,16%bymass)onthephysicalproperties,phasecompositionandmicrostructureswereinvestigatedthroughanX-raydiffractometer(XRD),ascanningelectionmicroscopy(SEM)andamicroscopymeasurementmethod,etc.Theresultsshowthat,forthespecimensfiredat1300℃withthekyanitecontentfrom8%to16%,thebulkdensitiesandapparentporositieschangelittle,butthecoldmodulusofruptureandthecrushingstrengthsdecreasesignificantly,andthelinearchangeratesincreasefrom-0.87%to0.64%.Themostappositemodeisthespecimencontaining12%kyanitefiredat1300℃,whichhasahighcrushingstrengthof29.3MPa,alowlinearchangeof0.18%,anapparentporosityof36.8%andabulkdensityof1.73g/cm~3.

简介：dodecyl1-pyrenylmethyl醚的聚集行为被荧光技术在dioxane水混合溶剂学习。标记的pyrenyl组在在聚集过程期间监视它的环境的极性变化是有效的。在探查环境的极性上基于象链长度效果，自我卷的效果，和分支组效果那样的结构的效果，总数的结构特征被讨论并且被用来在三cholesteryl酉旨和三长链链烷形成的总数上解释结构的特征的效果。

简介：在农业土地支持土壤碳隐遁是可行策略之一速度观察气候变化。然而，玷污物理骚乱由加速侵蚀加重了土壤降级过程。因此，减少通过适当farming/agricultural系统的物理骚乱是的土壤的大小和紧张对农业陆地的土壤碳水池能力的管理必要。不同土地的四个地点使用类型/耕种惯例，我)到没有为止(NT)玉米(ZeamaysL.)(NTC)，ii)到为止常规(CT)玉米(CTC)，iii)pastureland(PL)，和iv)本国的森林(NF)，在北方Appalachian试验性的分水岭车站，包括水马厩聚集在土壤总数索引上估计NT耕作的影响的美国俄亥俄，吝啬的重量直径(MWD)和几何平均数被选择直径(GMD)，和土壤器官的碳和全部的氮内容。收到的NTC阴谋恐吓粪肥增加(大约15t哈1)每隔一年。CTC阴谋包含了耕作的disking和凿子和液体化肥申请(110L哈1)。结果证明水马厩聚集和MWD比为CTC在为NTC的土壤是更大的。在0-10厘米土壤层，>4.75公里尺寸部分统治了NTC并且而在不同地点之中的1)跟随了NF的趋势，为CTC多于那是46%>PL>NTC>CTC，为在CTC上的NTC更是35%-46%。NT实践提高了在CT实践上并且这样的器官的碳内容是的土壤在农田的碳隐遁的重要策略玷污。

简介：Refractorymaterialsaresubjectedtomechanicalandchemicalloadsduringapplication,whichrespectivelyleadtofractureandcorrosion.Theunderstandingofthemechanicalfractureandthemicrostructuralmodificationafterprogressivethermalshocksisnecessaryforthesuitabledesignofhighperformancerefractorymaterials.Thefractureprocesszonecanbedividedintotwoareas,wheredifferenttougheningmechanismsarelikelytotakeplace:thecracktipandthefollowingprocessregioncalledwakeregion.Inthisstudy,theemphasisislaidonthemicrostructuralmechanismsoccurringinthewakeregionofthecrackandthecracktip.Therefore,functionalaggregates,namelyfusedeutecticaggregatesofAl2O3-ZrO2-SiO2andAl2O3-ZrO2,andandalusite,areaddedtoamodelhighaluminacastableformulationbasedontabularalumina.Thediscrepancyinthermalbehaviorbetweenaggregatesandmatrixaswellasphasetransformationsuchasmulliteformationfavorfurtherthenucleationofmicrocracksthatreducethestressfieldatthelevelofthecracktip.Twodifferentgrainfractionsoftabularalumina(0.2-0.6mmor2.24-3.00mm)aresubstitutedbythesefunctionalaggregates.Aftersinteringat1500℃for6h,thesamplesarequenchedupto10timesinairwithoutpressurefrom950℃toroomtemperature.Theresultingelasticpropertiesareexaminedaftereachthermalshockcycle,aswellastheresidualbendingstrengthafter0,1,3,5,7and10thermalshocks.TheseresultsarecorrelatedwithScanningElectronMicroscopyanalysesafterthedifferentthermalshockcycles.