SAE AS6039 Bearings, Ball, Rod End, Double Row, Self-Aligning

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Product Code:SAE AS6039
Title:Bearings, Ball, Rod End, Double Row, Self-Aligning
Issuing Committee:Acbg Rolling Element Bearing Committee
Scope:This specification covers sealed, self-aligning, anti-friction, rod end ball bearings with application in temperature ranges (1) -65°F to 250°F and (2) -65°F to 300°F with 20% reduction of dynamic load carrying capacity when subjected to operation above 250° F.
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【英文标准名称】:StandardSpecificationforBearing,Roller,Needle:ThickOuterRingWithRollersandCage
【原文标准名称】:滚柱和滚针轴承的标准规范:带滚柱和轴承保持架的粗外环
【标准号】:ASTMF2246-2003
【标准状态】:作废
【国别】:美国
【发布日期】:2003
【实施或试行日期】:
【发布单位】:美国材料与试验协会(ASTM)
【起草单位】:ASTM
【标准类型】:()
【标准水平】:()
【中文主题词】:滚柱;外圈;针;支承滚子;保持架;厚
【英文主题词】:Bearingrollers;Bearings;Cages;Needles;Outerrings;Rollers;Thick
【摘要】:
【中国标准分类号】:J11
【国际标准分类号】:21_100_20
【页数】:4P;A4
【正文语种】:英语


【英文标准名称】:StandardTestMethodforDeterminingtheChemicalCompositionandSequenceinAlginatebyProtonNuclearMagneticResonance(1HNMR)Spectroscopy
【原文标准名称】:质子核磁共振波谱法测定褐藻酸盐中的化学成分和序列的标准试验方法
【标准号】:ASTMF2259-2010
【标准状态】:现行
【国别】:美国
【发布日期】:2010
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:F04.42
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:Alginates;Biomedicalmaterials/applications;Chemicalanalysis--chemicals;Degradation--environmentalmaterials/applications;Monomersequence;Nuclearmagneticresonance(NMR)spectrometry;Pharmaceuticalindustry;TEMPs(tissueengineeredmedicalprodu
【摘要】:Thecompositionandsequentialstructureofalginatedeterminesthefunctionalityofalginateinanapplication.Forinstance,thegellingpropertiesofanalginatearehighlydependentuponthemonomercompositionandsequentialstructureofthepolymer.Gelstrengthwilldependupontheguluronicacidcontent(FG)andalsotheaveragenumberofconsecutiveguluronatemoietiesinG-blockstructures(NG>1).Chemicalcompositionandsequentialstructureofalginatecanbedeterminedby1H-and13C-nuclearmagneticresonancespectroscopy(NMR).AgeneraldescriptionofNMRcanbefoundinx003C;761>oftheUSP24-NF19.TheNMRmethodologyandassignmentsarebasedondatapublishedbyGrasdalenetal.(1979,1981,1983).,,TheNMRtechniquehasmadeitpossibletodeterminethemonadfrequenciesFM(fractionofmannuronateunits)andFG(fractionofguluronateunits),thefournearestneighboring(diad)frequenciesFGG,FMG,FGM,FMM,andtheeightnextnearestneighboring(triad)frequenciesFGGG,FGGM,FMGG,FMGM,FMMM,FMMG,FGMM,FGMG.Knowledgeofthesefrequenciesenablesnumberaveragesofblocklengthstobecalculated.NGisthenumberaveragelengthofG-blocks,andNG>1isthenumberaveragelengthofG-blocksfromwhichsinglets(-MGM-)havebeenexcluded.Similarly,NMisthenumberaveragelengthofM-blocks,andNM>1isthenumberaveragelengthofM-blocksfromwhichsinglets(-GMG-)havebeenexcluded.13CNMRmustbeusedtodeterminetheM-centeredtriadsandNM>1.Thistestmethoddescribesonlythe1HNMRanalysisofalginate.AlginatecanbewellcharacterizedbydeterminingFGandNG>1.Inordertoobtainwell-resolvedNMRspectra,itisnecessarytoreducetheviscosityandincreasethemobilityofthemoleculesbydepolymerizationofalginatetoadegreeofpolymerizationofabout20to50.Acidhydrolysisisusedtodepolymerizethealginatesamples.Freeze-drying,followedbydissolutionin99%D2O,andanotherfreeze-dryingbeforedissolutionin99.9%D2Oyieldssampleswithlow1H2Ocontent.TTHAisusedasachelatortopreventtracesofdivalentcationstointeractwithalginate.WhileTTHAisamoreeffectivechelator,otheragentssuchasEDTAandcitratemaybeused.Suchinteractionsmayleadtolinebroadeningandselectivelossofsignalintensity.Samplesareanalyzedatatemperatureof80x00B1;1x00B0;C.Elevatedsampletemperaturecontributestoreducingsampleviscosityandrepositionstheprotonsignalofresidualwatertoanareaoutsidethatofinterest.1.1ThistestmethodcoversthedeterminationofthecompositionandmonomersequenceofalginateintendedforuseinbiomedicalandpharmaceuticalapplicationsaswellasinTissueEngineeredMedicalProducts(TEMPs)byhigh-resolutionprotonNMR(1HNMR).AguideforthecharacterizationofalginatehasbeenpublishedasGuideF2064.1.2Alginate,alinearpolymercomposedofx03B2;-D-mannuronate(M)anditsC-5epimerx03B1;-L-guluronate(G)linkedbyx03B2;-(1>4)glycosidicbonds,ischaracterizedbycalculatingparameterssuchasmannuronate/guluronate(M/G)ratio,guluronicacidcontent(G-content),andaveragelengthofblocksofconsecutiveGmonomers(thatis,NG>1