简介:NineteenL-N-2-hydroxyethylaminoacidsandL-N,N-bis(2-hydroxyethyl)aminoacidswerepreparedfromthereactionofchlorohydrinwithL-alanine,L-valine,L-leucine,L-isoleucine,L-phenylalanine,L-serine,L-thrcunine,L-glutamicacid,L-asparticacidandglycine.L-N,N,N’,N’-tetra(2-hydroxyethyl)cystinewaspreparedbythereactionofL-cystinewithchlorohydrin.
简介:ByusingOH-terminatedpolyaryletherdendrimerandN-Fmoc-glycineasrawmaterials,thedendriticpolyarylether2-aminoacetate(G3-NH2)wassynthesizedviatwostepreactions.G3-NH2asamacroinitiatorforthering-openingpolymerizationofγ-benzylL-glutamateN-carboxyanhydridewasinvestigated.Itisfoundthattheresultingcopolymerspossessedrelativelyhighmolecularweightandnarrowmolecularweightdistribution(1.12
简介:Inthispaperwewillshowthatifanapproximationprocess{Ln}n∈Nisshapepreservingrelativetotheconeofallk-timesdifferentiablefunctionswithnon-negativek-thderivativeon[0,1],andtheoperatorsLnareassumedtobeoffiniterankn,thentheorderofconvergenceofDkLnftoDkfcannotbebetterthann2evenforthefunctionsxk,xk+1,xk+2onanysubsetof[0,1]withpositivemeasure.Takingintoaccountthisfact,wewillbeabletofindsomeasymptoticestimatesoflinearrelativen-widthofsetsofdifferentiablefunctionsinthespaceLp[0,1],p∈N.
简介:N-acetyl-D-methionine,NaAcandtheremainsofN-acetyl-L-methioninedramaticallyaffectthepurificationofL-methioninewhenpurifiedfromthemixtureofenzymaticallydeacylatedN-acetyl-DL-methionine,leadingtoalowyieldconventionally.Here,thispaperreportsasuccessfulseparationandpurificationofbothL-methionineandN-acetyl-D-methioninebyanHion-exchangecolumn.ThepH,L-Metconcentrationandtheratiobetweenthecontentofsodiumcationandtheion-exchangecapacitywereoptimizedtoobtainthemaximumyield.Experimentalresultsindicatethat,undertheoptimizedconditions,theyieldsofL-methionineandN-acetyl-D-methioninecanreachashighas85%and75%,respectively.
简介:让b=(b_1,···,b_m),b_i∈Λ_(β_i)(R~n),1≤i≤m,0<β_i<β,0<β<1,[b,T]f(x)=∫_(R~n)(K是aCalderon-Zygmund的b_1(x)-b_1(y))···(b_m(x)-b_m(y))K(x-y)f(y)dy,核。在这篇论文,我们显示出那[b,T]从L~p(R~n)toF_p~被围住(β,∞)(R~n),以及[b,从L~p(R~n)的I_α]到F_q~(β,∞)(R~n),在哪儿1/q=1/p-α/n。
简介:ObjectivesToevaluateantihypertensiveefficiencyandsafetyofanewdomesticofL-&N-typeCa^2+antagonist-eilnidipinewithimidaprilasapositivecontrol.MethodsAfter2weeks'placebowashingout,22patientsweretreatedwitheilnidipine5mgdailyand27patientsweretreatedwithimidapril5mgdaily.4weekslater,ifpatient'ssittingdiastolicbloodpressureisover90mmHg,his/herdosagewasdoubledforanother4weeks,theothersmeasuringupremainedtheirdosageunchangedforanother4weeks.Bloodpressure,heartrate,bloodandurineroutineexamination,serumglucose,serumchemicalexaminationincludingtotalcholesterol,triglyceride,HDL,LDL,transaminase,creatineetcandsidereactionswererecordedbeforeandafterthetrial.Datawereanalyzedstatistically.ResultsAfter8weeks'treatment,bloodpressurewassignificantlydecreased(P<0.05)inbothgroups,andthetwomedicineshadsimilarantihypertensiveeffects.Furthermore,thereducingofheartratewasstatisticallysignificantcomparedwithbaseline(P<0.01)inthecilnidipinegroup,butnotintheimidaprilgroup.Thenegativechronotropiceffectofcilnidipinehadlittleeffectoncontinuingthetherapy.Therewerenochangesonbloodandurineroutineexaminationandserumlipid,serumglucose,creatine,transaminaseandetcinbothgroups.Theirsidereactionsweremildandwell-tolerated.ConclusionsCilnidipinehasacon-vincingantihypertensiveeffectsimilartothatofimi-dapril.Especiallycilnidipinemaybeadministeredtopatientswithrelativelymildtachycardia.
简介:在褪黑激素的结构修饰中引入L-氨基酸形成N-(N-乙酰基-L-氨基酰基)-5-甲氧基色胺,这些化合物分别用小鼠甩尾法和人皮肤黑色素瘤细胞评价了镇痛活性和抗肿瘤活性,结果显示部分化合物的活性优于褪黑激素。
简介:Arareearthcoordinationsystemwasfirstinvestigatedasanewtypeofcatalystforthering-openingpolymerizationofα-aminoacidN-carboxyanhydrides(NCAs).Theresultsforthepolymerizationofγ-stearyl-α,L-glutamate(SLG)NCAusingneodymiumacetylacetonate(Nd(acac)3)-orneodymiumtris(2-ethylhexylphosphonate)(Nd(P204)3)-triethylaluminum-waterascatalystswerecomparedwiththoseusingconventionalcatalysts.Itwasfoundthatthehelicalpoly(γ-stearyl-L-glutamate)withhighmolecularweightaswellasnarrowmolecularweightdistributioncanbeobtainedinthepresenceofNd(acac)3/AlEt3-1/2H2O.ThepolymerobtainedwascharacterizedbyIRandNMRspectroscopy.
简介:TheFe-Ti-Nmateralloywaspreparedthroughthein-situreactionofnitrogengaswiththeFe-Timelt.ScanningelectronmicroscoperesultsshowthattheparticlesuniformlydistributedintheironmatrixwereTiN.ThedeliberatelypreparedFe-Ti-Nmasteralloywasemployedforthe409Lferriticstainlesssteelinanattempttorefinetheas-castsolidificationstructure.ItwasfoundthattheeffectivenessofFe-Ti-Nmasteralloyonrefiningoftheas-cast409Lferriticstainlesssteelwasaffectedbyadditionlevel,holdingtimeandmeltstemperature.Itwasfoundthattheaverageequiaxedgrainsizedecreasedfrom1503μmto303μm,theproportionofequiaxedgrainzoneincreasedfrom14%to100%withincreasingtheFe-Ti-Nmasteralloyadditionlevelto2.5%.Theproportionofequiaxedgraindecreasedfrom85%to4%asthesolidificationtemperatureincreasedfrom1803Kto1883K.Whentheholdingtimereachedto8min,thesolidificationstructuresof409Lferriticstainlesssteelshowextremepointsintheproportionofequiaxedgrain.Itisclearthatthegrainrefiningefficiencygraduallyfadeawaywiththeincreasingoftheholdingtimeattheverybeginning.However,whentheholdingtimecontinuestoincreaseandexceedstheextremepoint,thegrainrefiningefficiencyoftheFe-Ti-Nmasteralloyrecoveredtoacertaindegree.Theexperimentalresultsmentionedabovehavebeenanalyzedintermsofthermodynamics.Underappropriateconditions,theFe-Ti-Nmasteralloyusedforgrainrefinementofthesolidificationstructureof409Lferriticstainlesssteelmayhavegoodprospectsforindustrialapplications.