简介：Rareearthandtraceelementsaredeterminedforcassiteritefromavein—typeorebody,alensandasheeted-typeorebodyintheDachangSn-polymetallicorefield,GuangxiProvince.Cassiteritefromthevein-typeorebodyhasrareearthandtraceelementcharacteristicssimilartothatofDachangbiotitegraniteofLateYanshanage,showinganinheritableandageneticrelationship.Cassiteritesfromthelensandsheeted-veinorebodyhaverareearthandtraceelementcharacteristicsgreatlydifferentfromthoseofthevein-typecassiteriteandthegranite,showingdistinctlyhighercontentsoftheore-formingelementsAs,Sb.Zn.Agetc.andapositiveEuanomalyandanegativeCeanomaly.Thedifferenceofrareearthandtraceelementcharacteristicsforcassiteritefromtwokindsoforebodiesreflectsthecompositionaldifferenceofore-formingsolutions.Authorssuggestthatthelensandsheeted—veinorebodywasofnonmagmatic,mixedwithundergroundhotbrineorigin,andthatthiskindofhotbrinereactedwithDevonian

简介：摘要：东北地区寒冷的冬季给化工装置安全生产增加了难度，如何在冬季保证装置安全平稳生产以及冬季装置停工、开工操作顺利进行成为从10月份开始到次年4月份的重点工作，因此装置冬季操作策略方法成为重中之重。随着节能降耗和环保意识的增强，冬季开停工成为冬季操作策略关注的焦点。本文通过对1-己烯装置冬季操作策略的分析，探讨了冬季装置安全生产的方法和注意事项，为冬季安全生产提供保障。

简介：Cytarabine(1-β-D-arabinofuranosylcytosine,Ara-C),isolatedfromaCaribbeanspongespeciesTethyacrypta,isthefirstantitumordrugfromamarineresource.In1980,theUSFoodandDrugAdministrationapprovedthisdrugforthetreatmentofdifferenttypesofleukemia.Thisdrughasashortplasmahalf-life,lowstability,limitedbioavailability,andseveresideeffects.Toimprovestabilityandbioavailability,wesynthesizedninenovelderivativesbyblockingthecytarabinemetabolicsitesandimprovinglipophilicity.ThecLogPvaluesofthenewlysynthesizedcompoundswerecalculated.Allthesynthesizedcompoundsweremorelipophilicthancytarabine,resultinginmembranepermeabilityandbioavailabilityimprovement.TheantitumoractivitiesagainstleukemiacelllineHL-60wereevaluatedbyusingtheMTTassay.ThebioassayresultsrevealedthattheIC50valuesofcompounds5,8and9were0.080,0.090and0.057μmolL-1,respectively,whichwassimilarwiththatofcytarabine(0.056μmolL-1).Incomparison,compound4withaphosphategroupatO5’wasinactive.Becausephosphoesterbondsareeasilyhydrolyzedbyalkalinephosphataseandarecommonlyusedinproducingprodrugstrategies,compound4mightalsobemetabolizedinvivoandgeneratecompound3orevencytarabinethroughamulti-stepreaction.Thus,compound4mightbeapromisingcompoundtobedevelopedasaprodrug.

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简介：Euphausiapacificisanimportantsourceofnaturalastaxanthin.StudieswerecarriedouttoassesstheextractabilityofastaxanthinfromE.pacificusingsubcritical1,1,1,2-tetrafluoroethane(R134a).Toexaminetheeffectsofmultipleprocessvariablesontheextractionyield,astaxanthinwasextractedundervariousconditionsofpressure(30-150bar),temperature(303-343K),time(10-50min),flowrate(2-10gmin-1),moisturecontent(5.5%-63.61%),andparticlesize(0.25-0.109mm).Theresultsshowedthattheextractionyieldincreasedwithtemperature,pressure,timeandflowrate,butdecreasedwithmoisturecontentandparticlesize.Amaximumyieldof87.74%wasobtainedunderconditionsof100bar,333K,and30minwithaflowrateof6gmin-1andamoisturecontentof5.5%.Thesubstantialastaxanthinyieldobtainedunderlow-pressureconditionsdemonstratesthatsubcriticalR134aisagoodalternativetoCO2forextractionofastaxanthinfromE.pacific.

简介：以闽江河口感潮段塔礁洲野慈姑（SagittariatrifoliaL.）淡水湿地为研究对象,2015年12月—2016年10月每月小潮日定期向试验样地施加0、60和120kgS·hm-2·a-1的K2SO4溶液,探讨闽江河口感潮段淡水湿地CO_2排放通量特征对SO_4~（2-）沉降的响应,并同步观测主要环境因子。结果表明,1）对照（CK）和2个SO_4~（2-）沉降处理CO_2排放通量具有相似的月变化动态,夏秋季节排放通量较高,冬春较低。2）除夏季60kgS·hm-2·a-1的SO_4~（2-）输入显著降低CO_2排放通量外（P〈0.05）,2种SO_4~（2-）处理均未显著影响河口感潮段淡水湿地CO_2排放通量（P〉0.05）。3）相关分析显示,不同处理下的CO_2排放通量与土壤温度显著正相关（P〈0.01）。

简介：Sn-polymetallicoresatDachang,GuangxiAutonomousRegion,China,arehostedinMiddle-UpperDevonianreeflimestones,siliceousrocks,bandedandlenticularlimestones,etc.Twotypesoforebodiescanbedistinguishedaccordingtotheirtelationstothebedding:oneisdistributedalongthebeddingandthe.othercutsacrossthebedding.SnandsulfideorebodiesassociatedwithK-feldsparearemostlycharacterizedbylaminatedorestructure.MicroscopicexaminationsofK-feldspar-bearingrocks,inconjunctionwithX-raydiffraction,chemicalcomposiionandcathodoluminescencedataforK-feldspars,aswellastheirtelationstomineralization,theauthorsconsiderthattheK-feldspareareofauthigenicorigin,subordinatetotheepigeneticstageofdiagenesis,Theyresultedfromthereactionofmixed,deep-seated,circulatingundergroundhotwatersrichinK,AlandSiwithargillaceouscarbonatesduringtheIndonesianorogenicmovement.ItissuggestedmoreattentionshouldbepaidtotheeffectofauthigenicK-feldsparsonSnmineralization.Inthemeantimetheeventrelatedtocirculatingundergroundhotwatersshouldalsobetakenintoaccountsoastoprovidenewcluestoblindoreprospecting.

简介：Fromthepetrologicalstudyofore-hostingfockswhichcontainlargeanorthitscrystalsandtheoccurrenceandchemicalcompositionofanorthitesandrelatedminerals,theauthorsconsiderthatthelargeanorthitecrystalsareofauthigenicorigin.Thedistributioncharacteristicsofanorthites,i.e.,theyaredistributedalongthebeddingandstructurallyweakzonesbutnotrestrictedtosynsedimentaryslumpstructures,andtherelationshipforsomeelementsbetweenanorthitesandothermineralsindicatethatanorthiteshaveresultedfromreactionofcirculatingalkalinesolutionsrichinAlandSiwithcarbonatedduringtheIndosinianorogeny.TheresultsofthisworksuggestthattheassociationofauthigenicanorthiteswithbeddedorebodiesintheDachangorefieldmaybetheevidencethatthemineralizationisrelatedtocirculatingundergroundhotwaters.

简介：摘要：随着人们生活水平的提升，对食品安全性要求进一步提升，这也是人们生活状态发生改变的标志，从以往的吃饱穿暖，到现在的高质量生活。但是现在我们食用的一些视频在生长种植过程中往往会使用一些药物，提高其抗病虫害的能力。这些药物使用之后往往会产生一定的药物残留，为了保证人们饮食的健康，我国对相关的药物残留有明确的规定，必须在某个数值标准之下才能够进入食品加工行业，如果超过改标准可能会给我们的生活产生严重的影响。大豆、花生、豆油以及花生油这些产品也是我们生活中常用的，而大豆生长过程中往往也会喷洒诸如氟乐灵等药物，我国规定该药物的残留量要低于 0.05mg/kg。为了保证产品中药物残留的合格性，会用多重方法对其进行检测本文采用气相色谱法，对大豆、花生、豆油以及花生油中的氟乐灵残留进行测定

简介：1IntroductionDengfuxianorefieldliesattheintersectionoftheQin-HangCombinedZone(QCZ)andtheNanlingMetallogenic,andcomprisesXiangdongW-Sndeposit(AlsoknownasDengfuxianW-Sndeposit),Jiguanshi

简介：2012年1-2果洛由于持续降雪致使中北部发生雪灾,其中甘德达到了重度雪灾标准。本文利用实况观测资料及各种物理量场对造成此次雪灾的五次天气过程进行了分析和归纳,以期获得一些对果洛冬季降雪有指导意义的预报指标。

简介：摘要： 介绍了 1#芳烃装置利用 T-403加工处理 2#甲苯的过程和相关数据，对处理过程中出现的问题的进行了总结。

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简介：花生是一种食用价值较高的经济作物。我省花生过去有过零星种植,其生产之所以不能发展,缺乏花生气候适应性分析,未能充分而合理地利用气候资源,是主要原因。为了探索花生引种的可能性,发展我省花生生产,1982年以来,我们通过定点对比测定和地理播种等试验,获得了较好的效果。

简介：摘要水景与人居环境是紧密融合的，既可以在社区建设中引入水景水趣，美化小区环境，又可以凭借良好的人居环境保证景观水体的清洁、无污染。现阶段由于水景观设计是一项综合性的工作，其涉及的范围广，因素多，设计往往需要结合工程实际情况为业主提供美观、大方、安全、舒适的系统性方案。在绿化灌溉系统设计中，应优先利用天然水源，提高节水节能意识，努力做到精确灌溉，同时营造出绿色的人文环境。

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简介：本文探讨了荷电的BTZ黑洞的热辐射与非热辐射，给出了Hawking辐射谱及相应的温度表达式，并给出了非热辐射的有效势和粒子的能量公式。

简介：ThePengshanSn-Pb-ZnpolymetallicorefieldislocatedintheJiujiang-Ruichangregion,whichisasegmentofthemiddle-lowerYangtzeRivermetallogenicbelt.ThePengshanlateYanshanianburiedplutonwithgraniticcompositionisacalc-alkalinepluton,intrusionofwhichisresponsiblefortheformationoftheSn-Pb-Znpolymetallicdepositthroughprovidingthermodynamicconditionandore-formingmaterial.Thelong-activebasementriftsinitiallyformedintheJinningperiodandthedomalstructurewithinducedsecondaryorderfaultsformedbyemplacementofthepluton,suchasring-detachmentfault,top-detachmentfaultandjointfissure,actasthepassage-wayformagmaandore-formingfluidandimpoundingstructurefororedeposit.ThemagmatoformtheplutonwithDI＞90isintensivelydifferentiated.Thevariationoftheore-formingfluidincompositionwithfallingintemperaturecausedbyactionofmagmatichydrothermalconvectionsystemcombinedwithgroundwaterconvectionsystemattributestomineralizationofvarioustypesintheorefield.Themineralizationprocesscanbedividedintosixstages,i.e.,greisenization,skarnizationofearlystage,fluorite-stanniferoussilicationstage,skarnizationofadvancedstage,quartzandcassiterite-sulfurationstageandcarbonationstage.Themineralassemblagesformedindifferentmineralizationstagesaredifferentowingtotemperaturechangingandmaybeoverlappedinspace.Malayaiteisrecognizedfromthemineralassemblageformedinthefluorite-stanniferoussilicationstage.TheoresinthePengshanSn-Pb-ZnpolymetallicdepositarespatiallyzonedwithvariationfromAs-SnmineralassemblageofhightemperatureintheinnerzonethroughSn-PbandPb-Zn-Agmineralassemblageofmiddletemperatureinthemiddlezonetofluoritemineralassemblageoflowtemperatureintheouterzone.TheexchangingofSn,MgandFebetweenbiotiteandhydrothermalfluidresultedfromvariationofphysicochemicalconditionduringevolutionprocessesofthehydrothermalflu

简介：摘要水资源作为人类基础资源，在城市化道路上河流受到不同程度的影响，我国城市河流水污染和生态退化问题也越来越严重，在随着城市化快速发展和经济水平的提高，城市河流的生态环境是与我们息息相关的，对市民开放的一个生态系统。河流虽然有一定的自我净化恢复能力，由于附近居民增多，环保意识不强致使城市日常生产生活对河流造成了一定的影响，水污染不仅对城市生态景观功能造成了影响，还使得污染河道成为了城市的负担。

简介：摘要伴随着我国社会经济的不断发展，地下人防工程逐渐成为当前工程建设的重要组成部分，而人防结构设计也已经成为了建筑结构的主要内容之一。本文从人防工程的建设的现状出发，介绍了人防工程结构设计的重要性及设计原则，对人防工程结构设计的关键点进行了深入分析与探讨，以供参考。