工业机器人装备技术

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1、ToxicityofMetalsAllmetalsarepotentiallytoxicAllmetalsarepotentiallytoxicathighconcentration,eventhoughsomeofthemarealsoessential.MetabolismofmetalsInorganicmetalcompounds无机非金属Acombinationofabsorption,storageandeliminationOrganometalliccompounds有机金属化合物Metabolizedbydifferentbiochemicalpath

2、waysToxicmechanismHighaffinityforessentialaminoacidsidechainse.g.sulfhydryl,histidyl,andcarboxylgroupsReactdirectlywithproteinstoalterenzymaticfunctionBindtocofactors,vitaminsandsubstratesalterbiologicalfunctionsPresenceofanexcessofanymetalmayleadtodepletionofessentialmetalsChelationThe

3、rapyChelationistheformationofametalioncomplexwithaligand.Theligandmaybemonodentate,bidentate,ormultidentate(i.e.itmaycoordinatewithusingoneortwoormoredonoratoms)Chelatingagentsaregenerallynon-specificmobilizeandenhancetheexcretionofawiderangeofmetals,includingessentialmetalsArsenic砒霜，砷O

4、neoftheoldestpoisonsTrivalentarsenicismoretoxicthanpentavalentarsenicArsenic(II)Thepyruvatedehydrogenase(PDH)systems,whichconvertspyruvatetoacetylcoenzymeA.DLDHisdihydrolipoyldehydrogenasethatgeneratesthedihydrolipoamide1,3-dithiol(arrow)responsibleforbindingmetals.Ageneraltoxicitymechan

5、ismsformanyheavymetalsTwoformsinacutearsenicpoisoningParalyticformlargedosesareabsorbedquicklydevelopsymptomsquicklyConstrictionofthroatfollowedbydysphagia(difficulttoswallow)paralysisdeathGastrointestinalformWaterydiarrheacausedbyparalysisofthecentralmechanismofthecapillarycontrolinth

6、eintestinaltract.bloodvolumeandbloodpressureshockDisturbedheartactionandcausedeathChronicarsenicpoisoningBeginsaslocalerythemawithburninganditchingmottledskinSwellingandvesiculareruptionsMelanosisoneyelids,temples,neckandtrunkHyperkaratosisformationofwartsMee’sline(horizontalwhiteband

7、sacrossnails)NasalseptumulcerationMercuryLiquidmetaloccursnaturallyObtainedbyheatingthewidelyfoundsulfidemineral,cinnabar(HgS)Dissolvesmanyothermetalstogivesolidsolutions,calledamalgams(wasusedforfillingsindentistry)Mercuricchloridehasbeenusedinmedicineformorethan3000year