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简介：摘要随着国民经济的高速发展，人们追求生活的舒适性和快捷性，对生活质量提出了更高的需求，特别是环境污染方面。这里主要介绍了氡浓度对人体的危害、氡的常识、RAD-7测氡仪简介以及《民用建筑工程室内环境污染控制规范》中土壤氡浓度的测试方法，探讨了RAD-7测氡仪测试土壤氡浓度以及对检测结果产生的影响。

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简介：Inordertoseparatemethylacetateandmethanolazeotrope,theionicliquid(IL)1,3-dimethylimidazoliumdimethylphosphate([DMIM]DMP)wasusedasthesolvent.TheAspenPlussoftwarewasusedtodesignandoptimizetheextractivedistillationprocess.Undertheoptimizedconditions,themassfractionsofmethylacetateandmethanolwerebothabove99.5%.Comparedwiththedimethylsulfoxide(DMSO)process,the[DMIM]DMPprocesshastheadvantagesofsavingenergyandlowerequipmentinvestmentcost.Theresultshowsthatusing[DMIM]DMPasthesolventtoseparateamethylacetateandmethanolazeotropehasbetterprospectinindustrialapplication.

简介：Methyldiethanolaminefattyacidesters,viz.methyldiethanolamineoctanoateandmethyldiethanolamineoleate,wereprepared.Theirimpactsonthebiodegradabilityandtribologicalpropertiesofmineralbaseoil400SNwereevaluatedbyatesterforfastevaluatingthebiodegradabilityoflubricantsandbyafour-balltester,respectively.Theresultsshowedthatmethyldiethanolamineoctanoateandmethyldiethanolamineoleatebothcouldmarkedlypromotethebiodegradationoftheoilandimproveditstribologicalproperties.Theimprovementofbiodegradabilitywasattributedtotheenhancedgrowthandquantityofmicrobesbymethyldiethanolaminefattyacidesters.Thewornsurfaceswereanalyzedbyascanningelectronmicroscope(SEM)equippedwithanenergydispersivespectrometer(EDS)andanX-rayphotoelectronspectroscope(XPS).Theresultsindicatedthattheenhancementoffriction-reducingandanti-wearpropertiesofthemineraloilwasattributedtotheformationofcomplicatedboundarylubricationfilmscomposedofspeciessuchasFe2O3,Fe3O4andorganicnitrogen-containingcompoundswithastructureof–C-N-orR-NH2.

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简介：ActiveFe-andMn-loadedMCM-41(Fe–Mn/MCM-41),whichwassynthesizedviaahydrothermalreactionfollowedbyimpregnation,isusedintheheterogeneousFentonreactiontodegrademethylorange(MO)inaqueoussolution.ThesynthesizedsampleswerecharacterizedbyX-raydiffraction,scanningelectronmicroscopy,transmissionelectronmicroscopy,N2adsorption–desorptionisothermanalysis,Fouriertransforminfraredspectroscopy,andX-rayphotoelectronspectroscopy.ComparedwithFe/MCM-41andMn/MCM-41,Fe–Mn/MCM-41showedhigheractivityforMOdegradationandmineralization.Effectsofvariousoperatingparameters,suchaspH,Mncontent,andH2O2dosage,onthedegradationprocessweresubsequentlyinvestigated.ResultsofexperimentsontheeffectofradicalscavengersrevealedthatthedegradationofMOcouldbeattributedtooxidationbyHO·.ThesynergyofFeandMnspeciesintheFentonoxidationprocesswasalsoexplained.

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简介：目的探讨DNA修复基因RAD523＇非翻译区（3＇-untranslatedregion,3＇-UTR）miRNA靶序列单核苷酸多态性（singlenucleotidepolymorphism,SNP）与广西地区人群肝细胞癌（hepatocellularcarcinoma,HCC）遗传易感性的关系。方法采用病例-对照研究,对1002例确诊的HCC新发病例和1013例非肿瘤患者RAD52基因3＇-UTR区域miRNA靶序列SNPs（rs1051669、rs1051672、rs7301931和rs7310449）进行基因分型,并分析其基因型频率分布及其与HCC遗传易感性的关系。结果RAD52基因各SNP基因型在病例组和对照组中的分布频率差异均无统计学意义（P〉0.05）。调整年龄、性别、吸烟、饮酒和HBV感染等因素后,未发现各SNP与HCC易感性有关联;分层分析发现,在女性人群中,与携带rs1051669C等位基因相比,TT基因型可显著降低个体罹患HCC的风险（TTvsCT/CC：OR=0.03,95%CI：0.00～0.62,P=0.03）;与携带rs1051672G等位基因相比,AA基因型可显著降低个体罹患HCC的风险（AAvsGA/GG：OR=0.03,95%CI：0.01～0.88,P=0.04）。结论RAD52基因3＇-UTR区域miRNA靶序列SNPsrs1051669、rs1051672位点可能与广西地区女性人群HCC易感性有关。

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