简介：Theadsorptiveremovalofarsenicbysynthetically-preparednanoFe-Mnbinaryoxides（FM）wasinvestigated.AnovelmethodusingpotassiumpermanganateandferricchlorideasrawmaterialswasusedtosynthesiseFM.ThemolarratioofFeandMninthesyntheticFe-Mnbinaryoxideswas4:3.TheFM-1andFM-2（preparedatdifferentactivationtemperatures）havinghighspecificsurfaceareas（358.87and128.58m2/g,respectively）wereamorphousandofnanoparticletypes.TheamountofarsenicadsorbedonFM-1washigherthanthatadsorbedonFM-2particles.AfteradsorptionbyFM-1,residualarsenicconcentrationdecreasedtolessthan10μg/L.Theadsorptionkineticsdatawereanalyzedusingdifferentkineticmodelsincludingpseudofirst-ordermodel,pseudosecond-ordermodel,Elovichmodelandintraparticlediffusionmodel.Pseudosecond-orderkineticmodelwasthemostappropriatemodeltodescribetheadsorptionkinetics.TheadsorptionpercentageofAs（Ⅲ）increasedinthepHrangeof2–3whileitdecreasedwiththeincreaseofpH（3

简介：Understandingtheeffectsoforganicacids（OA）onthetransformationofFeandMntosurfacewaterfromtheweatheringcoalgangueisofgreatbene?ttoriskassessmentandremediationstrategiesforcontaminatedwaterandsoil.BasedontheinvestigationonsurfacewaterinthecentralcoaldistrictsoftheGuizhouProvince,18watersampleswerecollectedforheavymetalanalysis.TheresultsindicatedthatthepHvalueofsurfacewaterislow（3.11–4.92）,andFeconcentration(1.31–5.55mgL-1)andMnconcentration(1.90–5.71mgL-1)were,onaverage,10.86and34.33timesthelimitofSurfaceWaterQualityStandards,respectively.InordertoevaluatetheeffectsoftheOAonthedissolutionofFeandMnfromtheweatheringcoalgangue,columnelutionandbatchleachingexperimentswereconducted.Theresultsshowthatthelowmolecularweightoforganicacids（LMWOAs,i.e.,oxalic,tartaric,malicandcitricacids）andfulvicacidssigni?-cantlyacceleratedthedissolutionofFeandMn;inaddition,whentheconcentrationofOAreached25mmolL-1,theconcentrationsofFe,andMnwere1.14–67.08and1.11–2.32timesashighasthosein0.5mmolL-1OA,respectively.Furthermore,themigrationofFeandMnwassigni?cantlyin?uencedbythepHandEh,especiallyforFe;theionMnwasdissolvedfromtheganguemoreeasilythantheionFeinthecolumnleaching,whichwascontrarytotheresultsofbatchleaching.

简介：ThestrongadaptabilityofBroussonetiapapyrifera(L.)Vent.tolowphosphorus(P)conditionscanbeattributedtothelargeamountofroot-exudedorganicacidsandthehighef?ciencyofPextraction.However,microelementcontentsarein?uencedbylow-Pstress,andtheireffectsonthephotosyntheticcapabilityofB.papyriferaremainunknown.Inthisstudy,weinvestigatedtheeffectsoflow-Ptreatmentonnetphotosyntheticrate(P_N);chlorophylla?uorescence(ChlF)characteristics;andFe,Mn,Cu,andZncontentsofB.papyriferaandMorusalbaL.seedlings.ResultsshowthatB.papyriferaexhibitedbetterphotosyntheticcapabilityundermoderatePde?-ciency(0.125,0.063,and0.031mmol/LPtreatments),whereasthephotosyntheticcapabilityofM.albadecreasedundermoderateandseverePde?ciency(0.016and0mmol/LPtreatments).UndermoderatePde?ciency,thedecreaseinCuandZncontentsinB.papyriferawaslowerthanthatinM.alba.UnderseverePde?ciency,aconsiderabledecreaseofphotosyntheticcapabilityinB.papyriferaandM.albawasassociatedwithlowCuandZncontents.ThePNofthetwoMoraceaespeciesexhibitedabettercorrelationwithCuandZncontentsthanwithFeorMncontent.Pde?ciencycouldnotonlydecreasecyclicphotophorylationandphotosyntheticef?ciency,butcouldalsoaffectthestabilityofthylakoidmembranestructureandelectrontransportef?ciencybyin?uencingthecontentsofCuorZn,therebyaffectingphotosynthesis.

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简介：摘要：对一种10mm厚Al-4.3Zn-1.3Mg合金板材进行时效处理并研究了不同时效制度对板材力学性能和组织的影响规律。结果表明，当采用120℃/28h的工艺制度进行时效处理时，板材获得了最佳的强度性能。

简介：摘要：对一种10mm厚Al-4.3Zn-1.3Mg合金板材进行时效处理并研究了不同时效制度对板材力学性能和组织的影响规律。结果表明，当采用120℃/28h的工艺制度进行时效处理时，板材获得了最佳的强度性能。

简介：WeperformedasystematictraceandrareearthelementanalysisforthebeddedFe-MncarbonaterocksrelatedtothestratiformAg-Pb-ZnmineralizationintheLengshuikengoredistrict,JiangxiProvince,SouthChina.ThreetypesofFe-Mncarbonatesaredistinguished,namely,themassive,breccia,andveintypes.Bothcarbonateandsilicatefractionsinthesamplesareanalyzedfortheirtraceandrareearthelementconcentrationsusingastepacid-leachingtechnique.OurresultsshowthatthecarbonatefractionsinthemassivetypesampleshavethelowestREEconcentrationsbutpronouncedpositiveEuandYanomalieswithEu/Eu*valuefrom1.3to6.2andY/Hovaluefrom40.1to59.5,andsimilarcharacteristicsarealsoshownforthesilicatefractionsinthemassivetypesamples(Eu/Eu*=1.0–6.7,Y/Ho=20.7–55.1).TheseREEcharacteristicsaresimilartothoseofSedextypemassivesulfidedepositsworldwide,andwesuggestthatthemassivetypeFe-Mncarbonaterockswerelikelyformedfromanexhalativevolcanic-hydrothermalfluidfeedingthedepressionbasinofavolcaniclake.Thehighconcentrationsofredox-sensitiveelementsandratiossuchasU/Th,V/CrandV/(V+Ni)indicateadysoxicenvironmentfortheFe-Mncarbonatedeposition.Incontrast,thebrecciatypeandveintypeFe-Mncarbonatesamplesshowdifferenttraceandrareearthelementfeaturesfromthoseofmassivetypesamples,andtheyaremoresimilartothevolcanicrocksandmagmatic-hydrothermalfluidsintheLengshuikengoredistrictandmayreflectstrongoverprintingfromvolcanicandsub-volcanicmagmatismrelatedtotheporphyrytypemineralizationinthedistrict.

简介：通过实验建立了野外水质Fe2+、Fe3+的测定方法，不用电力和携带仪器设备，目视比色。简便快速，具有较好的准确度。

简介：Fouriertransformedinfraredspectrometry(FTIR)and27AlMagicAnglespinning(MAS)nuclearmagneticresonancespectroscopywereemployedtocharacterizearsenateadsorptiononamorphousAlgelswithKegginstructureatpH=4–10.Thesestudieshaveproventhat:thesurfacecomplexspeciesofarsenateshowsignificantdifferencesunderacidicandalkalineconditions,whichwasdeducedbasedontheAs-Ostretchingvibrationbandslocatedrespectivelyat774and870cm-1;poorlycrystallineAl13(orAl)-arsenateprecipitationcouldbeeasilyformedunderacidmediumconditionandhighloadinglevel,whichwassupportedbycomparingtheAs-Ovibration(at≈732cm-1)ofprecipitationtoadsorbedAlgels;arsenate(AsO43-)adsorptionhasnoeffectontheKegginstructureofAlgelswithbasicity(R)=2.6and3.0,evenathighloadinglevel,asevidencedbythesignalat≈63×10-6ofmagicanglespinning(MAS)-27AlNMR.Theadsorptionenvelopewasdeterminedbyconventionalbatchexperiments.

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简介：Metalgrainsinstonymeteoritesarerelativelymovableduringthermalnetamorphism(Wood,1967;XieandWang,1979;Xie,1986).InviewofthefactthattheJilinmeteoriteisthelargestintheworldknownuptonow,itsmainbodyweighing1770kganditstotalvolumeamountingto117×93×84cm^3,ade-tailedinvestigationintosuchahugemeteoritebodywouldundoubtedlyprovideuswithalotofcluesandinformationvaluableinthestudyofthebehaviorofFe-Nimetalduringthermalmetamorphismofmeteorites.OurrecentinvestigationhasrevealedthatduringthermalmetamorphismoftheJilinchondirtefineFe-Nimetalparticlesmigratedeasilybydiffusioninsolidstate,andsubsequentlyaggregatedintometalnodulesabout5-10mminlength,andthelargestnodulewefoundis30mminsize(Photo1).Inthispaperwepresentsomenewresultsofourstudyconcerningthemigra-tionandconcentrationofFe-NimetalintheJilinchondriteonthebasisofop-tical,SEMobservationsandhigh-temperature-highpressureaswellasshockloadingexperiments.

简介：Evaluationofthesound-structureinteractionisimportantforeffectivecontrolofnoiseandvibrationinstructuralacousticsystems.Crackedelasticstructure-soundinteractionproblemsarestudiedbyemployingthehybridfractalFEMandBEM.ThedegreesoffreedomofthesystemcanbereducedgreatlythroughadoptingfractalFEMindiscretizingthecrackedelasticstructure;whiletheexterioracousticfieldiscalculatedbyBEM,whichautomaticallysatisfiesSommerfeld'sradiationcondition.Numericalexamplesaregivenandshowthattheresonantfrequenciesofthestructure-acousticcoupledsystemdecreaseasthedepthofthecrackincreases,andthatthecrackhasasignificanteffectontheacousticalfieldinthevicinityofthecracktip.

简介：摘要：以304钢为基础，分别加入质量分数为1.5%、2%、3%的Al，利用中频无芯感应电炉熔炼并浇入树脂砂型试样中，将熔炼制备的样切成金相试并对腐蚀性能测试。研究了Al质量分数为1.5%、2.0%、3.0%的不锈钢的抗晶间腐蚀性能。结果表明：Al质量分数为2%的合金具有最佳的抗晶间腐蚀性能。

简介：摘要：巴氏合金作为传统的轴瓦材料，其具有良好的顺应性、耐蚀性和耐磨性。但是，由于巴氏合金质地相对较软，需要与强度较高的基材进行复合，才能够作为轴承衬套使用在工业制造中。传统的巴氏合金轴瓦制备方式多为离心浇铸，此类巴氏合金轴瓦偏析严重，组织粗大，结合强度低且极易发生脱落。各种缺陷如气孔、疏松等也经常出现在离心浇铸的巴氏合金轴瓦产品中。铝合金材料由于其自身质量小，且耐蚀性能优良，在加工时成形性能好，同时某些铝合金的导电导热性也比较好，因此被广泛应用在航空航天以及各类动力交通领域中。文中选用铝合金材料为基材，利用 MIG焊工艺，在铝合金表面堆焊巴氏合金层，系统地研究在其他焊接工艺参数（如焊接电流、电弧电压等）不变的情况下，焊接速度对结合界面的显微组织、力学性能等问题的影响。

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简介：摘要：随着焊接技术不断发展，有效推进我国的工业化生产进入一个新的阶段。其中在汽车产业当中，焊接自动化技术发挥着重要作用。在当前我国社会发展下，焊接技术逐渐走向自动化的发展方向，以此为根据，探讨焊接自动化技术在汽车焊接过程中的应用，旨在为相关领域发展研究提出更多的意见。

简介：摘要：襄阳融创·滨江壹号项目有47层、42层超高层建筑，根据前期当地市场调研及考察，同时结合业主要求，为保证现场施工质量及施工进度，特对铝合金模板施工体系提出此优化方案，从而降低施工难度，保证施工质量。

简介：摘要：研究表明，铝合金的特殊结构使它的耐蚀性和耐腐蚀性得到极佳的发挥。它的密度极小，熔点极低，热传导率极佳，热膨胀率极高，还拥有极强的化学稳定性，容易被氧化，而氧化物的熔点也极为可观。因此，在制造和应用铝合金的过程中，几种最新的焊接技术都发挥着重要作用，为改善它的耐蚀特性和耐腐蚀性。

简介：为探讨洞穴次生碳酸盐沉积U元素含量变化的气候环境意义,以川东北狮子洞石笋SI3为研究对象,通过对SI3的U/Ca值进行分析,发现在53.2~45.8ka之间SI3的U/Ca值变化与该石笋和格陵兰冰心NGRIP的δ^18时期偏大,在夏季风增强时期偏小。此外U/Ca值很好地记录了H5冷事件和GIS12、GIS13及GIS14暖事件。

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