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121.
IntroductionSupportedPt-Sncatalystsareimpo~inthepdrileumandpthechendcalindustricsbecauseoftheirsuperiorcatalyticperformances.Forexample,Pt-Snsupportedonaneutralsupporthasbeenreportedtoexhibithighdehydrogenationselectivityanddebilitythansupportedplatinumca… 相似文献
122.
1 INTRODUCTION In the past decades, metal disulphides have recei- ved much attention due to their diversity struc- tures[1~4] and applications as potential ligands for metal ions in biological system[5]. Metal disulfide compounds are usually prepared from the direct reactions of metal ions with organic disulphide[1~5], while some others are isolated from the reactions of metal salts and thiolates with the presence of certain oxidizing agents (e.g., O2, H2O2, etc.)[6, 7]. A large number o… 相似文献
123.
Reported here is the electrocatalytic reduction of molecular oxygen in the presence of water-soluble cobalt(Ⅱ) tetrakis(4-trimethyl ammonium phenyl) porphyrin (Co(Ⅱ)TTAPP) as catalyst in solutions of various pH values. The overpotential of molecular oxygen reduction is reduced by ca. 200-400 mV in acidic and neutral solutions compared with several decades of millivolts in alkaline solutions, indicating that Co(Ⅱ)TTAPP possesses much higher catalytic activity in acidic and neutral solutions than in alkaline. H2TTAPP in solutions of various pH exhibits no significant catalytic activity for oxygen reduction. The significant difference in the electrocatalytic activity of Co(Ⅱ)TTAPP from that of H2TTAPP for oxygen reduction indicates that the electrocatalytic activity of Co(Ⅱ)TTAPP should be attributed to the central cobalt atom (Co(Ⅱ)) coordinated by N4 internal ring in Co(Ⅱ)TTAPP. The total number of electrons involved in oxygen reduction electrocatalyzed by Co (Ⅱ)TTAPP is 2, and the product of suc 相似文献
124.
Toluidine blue(TB) is a good sensitizer for the polymerization of acrylnmide(AM) induced by He-Ne laser. With TB as a sensitizer and various alcoholamine as donors, the photoredox of TB and the polymerization kinetics of AM induced by He-Ne laser were investigated. It was found that either for the photoredox of TB or for the polymerization of AM, the activity of alcoholamine increases in the order of EOA相似文献
125.
PiezoelectricFiber-opticSpectroelectrochemistry──ANewTechniqueofSpectroelectrochemistryinCombinationWithPiezoelectricQuartzCr... 相似文献
126.
StudiesonArtificialImitationofGlutathionePeroxidasebyChemicalMutationDINGLan;ZHUZhen-qi;LUOGui-min;SUNQi-an;YANGTong-shuandSH... 相似文献
127.
IntroductionHardcarbonfilmsprcparcdb}'vari0usplasmaprocesscsareofc0nsidcrablcinterestbccauscofthcirunusualmcchanical-opticalandelcctricalpropertiesll~3l.Rccently,ithasReceive(IJl111c5,l9`)5;,.`,1iis()tI1ie)\tioII,1'ceil'edJtl1)'l4,l995*'I11isprojectiss[1pportcdh}tl1cNatiol1a1Nat[lntlScicl1ccI`()ul1dati()l1ofCl1il1aal1dtl1eI,aboraton'ofSolidI,ubricati()l1,l.al1/l10ulnstitutcofCl1cn1icalPh\'sics,111cChincscAcadcl11\'ofScicnccs.benfoundthattheinc0rporati0nofmetaIintocarbonfilmscangrcatl}'… 相似文献
128.
Cunninghmia lanceolata Hook. is a traditional Chinese medicine used for thetreatment of hernia, arthritis and strangury. its chemical constituents have beenexamined]' 2' 3' '. In a previous paper we reported a bislabdane-type diterpenoidlanceolatic acid from the roots of the plant 5. Further chemical studies on this plantled to the isolation of another new bislabdane-type diterpenoid, named lanceolatin(I ).Compound I was obtained as white amorphous powder. mp 232-234 'C, [a]."-24 (c 0. 10, C… 相似文献
129.
Removal of Endotoxin from Human Serum Albumin Solutions by Hydrophobic and Cationic Charged Membrane 总被引:1,自引:0,他引:1
Removal of end6toxin from medicine injection is very important, becauseendotoxin withpotential biological activity causes pyrogenic and shock reactions in' mammals-'on...intravenous injection even as law as "an6gram amounts. Endotoxin, a constituent ofpotential contaminant of physiological fluids and aqueous solutions 'and very stable atextreme temperature and PH values. For removing endotoxin from solutions ofbiomolecules, such as HSA, adsorption techniques are usedl.' Many methods forendot… 相似文献
130.
INTRODUCTIONInrecentyearsresearchprojectsonROMPofcycloolefinshavebeenattractingattentionofscientistsengagedinthesynthesisanddesignofnewpolyTneric'AprojectsupportedbytheNationalNaturalSCienceFoundationofChina(projectapprovalnumber:29474160).'-Correspondingauthormaterials,amongthemROMPsofnorbornene,norbornenederivativesandDCPDhavefoundgrowingfavourinthechemists,.y.,LI--4].Acrosslinkedpolarer(PDCPD),anewplastic,possessingexcellentmechanicalproperties(highNIS,TSetc)a-ndgoodthermal… 相似文献