STUDIES ON THE ELECTROANALYTICAL CHEMISTRY OF RARE EARTH ELEMENTS——POLAROGRAPHIC CATALYTIC WAVE OF EUROPIUM-XYLENOL ORANGE SYSTEM

A sensitive catalytic wave of Eu~(3 )-XO in derivative single-sweep polarography is pro-posed. The detective limit is 5×10~(-8)M Eu, and the linear range is 1×10~(-7)M-1×10~(-5)M. The mechanism of this catalytic wave has been studied by several experimental methods.It is proved that the catalytic wave behaves as an adsorptive-complex wave as well as an ECcatalytic wave in which free radical formed by the reduction of XO acts as an oxidizingagent. For this reason, Eu~( 3)-XO is the most sensitive catalytic wave among the rareearths.     

STUDIES ON THE ELECTROANALYTICAL CHEMISTRY OF RARE EARTHS——THE ADSORPTIVE-COMPLEX WAVE OF THE COMPLEXES OF N, N'-DI-(2-HYDROXY-5-SULPHOPHENYL)-C-CYANFORMAZAN (DSPCF) AND LIGHT RARE EARTH ELEMENTS

The sensitive adsorptive-complex wave of the complexes formed by light rare earth elements and DSPCF is studied in this paper. The electroactivities of the complexes of light (La-Eu) and heavy rare earth elements (Gd-Lu), are quite different, so we can determine a certain light rare earth element or the total amounts of light rare earths without separating them from heavy rare earths. The mechanism of the adsorptive-complex wave and the reason why heavy rare earths could not form the electroactive complexes have been studied as well.     

THE POLAROGRAPHIC ADSORPTIVE COMPLEX WAVES OF RARE EARTHS WITH CARBOXYNITRAZO (CNA)~*

The single-sweep polarographic adsorptive complex wave of Nd~(3+)-CNA and the differential pulse polarographic wave of La~(3+)-CNA are studied. 5×10~(-7)-8×10~(-6) M Nd~(3+) and 1×10~(-8)-1×10~(-6) M La~(3+) can be determined respectively. Lanthanum content in leaves of water-cultured cucumber has been determined. Experimental facts showed that CNA and the complex of Nd~(3+)-CNA can be adsorbed on the mercury electrode. The reduction mechanism of the adsorptive complex wave is proposed.     

NOVEL PEROXO COMPLEXES OF RARE EARTH METALS CONTAINING 1,10-PHENANTHROLINE AS A COLIGAND

ＮＯＶＥＬ　ＰＥＲＯＸＯ　ＣＯＭＰＬＥＸＥＳ　ＯＦ　ＲＡＲＥ　ＥＡＲＴＨ　ＭＥＴＡＬＳ　ＣＯＮＴＡＩＮＩＮＧ　１，１０－ＰＨＥＮＡＮＴＨＲＯＬＩＮＥ　ＡＳ　Ａ　ＣＯＬＩＧＡＮＤＮＯＶＥＬＰＥＲＯＸＯＣＯＭＰＬＥＸＥＳＯＦＲＡＲＥＥＡＲＴＨＭＥＴＡＬＳ...     

STUDIES ON THE POLAROGRAPHIC ADSORPTIVE COMPLEX WAVE OF RARE EARTH-ERIOCHROME AZUROL B (Ⅰ)

The polarographic behaviour of eriochrome azurol B (ECAB), one of complexing agentsof rare earths (RE), has been studied by several electrochemical techniques. The results showedthat the first step of one-electron reduction is reversible and the second step is irreversible, thatpart of the radical formed after the first electron transfer dimerizes, and that the cathodic andanodic peaks of ECAB at low concentration are adsorptive ones. The rate constant of dime-rization and some parameters related to adsorption of ECAB such as surface concentration,adsorption isotherm, free energy of adsorption and coverage of surface weIe calculated. The polarographic properties of RE-ECAB complexes and the reduction mechanism will bereported in the following paper (Ⅱ).     

STUDIES ON COMPLEXES OF RARE EARTHS WITH CROWN ETHERS(Ⅳ)SYNTHESIS AND CHARACTERIZATION OF THE COMPLEXES OF RARE EARTH NITRATES WITH 4''''-BROMO-5''''-NITROBENZO-15-CROWN-5

Six new solid complexes of macrocyclic polyether ligand 4′-bromo-5′-nitrobenzo-15-crown-5(L)withUivalent rare earth nitrates having composition of RE(NO_3)_3·L·mCH_3CN·nH_2O(RE=L_a--Nd,m=n=0,RE=Sm,Bu,m=0.1,n=1,4)have been synthesized in acetonitrile or acetone.All the isolated complexes have been char-acterized by elementary analysis,IR and UV spectra,differential thermal and thermogravimetric analysis,X-ray powderdiffraction analysis,molar conductance and measurementa of solubility in some general solventa.It shows thatcoordination number of the rare earth cation in the complexes of La,Ce,Pr and Nd nitrate is eleven.     

STUDIES ON THE POLAROGRAPHIC ADSORP-TIVE COMPLEX WAVE OF RARE EARTH-ERIOCHROME AZUROL B (Ⅱ)

The rare earth ions form complexes with ECAB in 0.1 mol/L NaAc-HAc supporting electrolyte at pH 6. The composition of the complex was determined by spectrophotometric method to be 1: 2. The decrease of SAC peak height of ECAB is proportional to the concentration of rare earth ions in the range of 1×10~(-6)-2×10~(-5) mol/L. The reduction mechanism of ECAB and RE-ECAB is proposed based on the experimental evidence. The complexing group of ECAB with RE ions iust is the redox group, so when RE ions are added, there is no new peak appearing in the polarograms:, the only phenomenon observed is that the peak current of ECAB decreases. The fast protonation of EGAB carbanion formed after the second electron transfer results in the formation of colourless tetrahedral molecules.     

SYNTHESIS AND ANTI－HIV－1 ACTIVITY OF HETEROPOLY COMPLEXES OF TUNGSTOTITANOPHOSPHATES CONTAINING RARE EARTH ELEMENTS

ＳＹＮＴＨＥＳＩＳ　ＡＮＤ　ＡＮＴＩ－ＨＩＶ－１　ＡＣＴＩＶＩＴＹ　ＯＦ　ＨＥＴＥＲＯＰＯＬＹ　ＣＯＭＰＬＥＸＥＳ　ＯＦ　ＴＵＮＧＳＴＯＴＩＴＡＮＯＰＨＯＳＰＨＡＴＥＳ　ＣＯＮＴＡＩＮＩＮＧ　ＲＡＲＥ　ＥＡＲＴＨ　ＥＬＥＭＥＮＴＳＳＹＮＴＨＥＳＩＳＡ...     

STUDIES ON COMPLEXES OF RARE EARTHS WITH CROWN ETHERS(V)-SYNTHESIS AND CHARACTERIZATION OF THE COMPLEXES OF RARE EARTH NITRATES WITH 2,2''''-DINITRO-4,5,4'''',5''''-BIS-(15-CROWN-5)-DIBENZO DISULFIDE

Three new solid complexes of macrocyclic polyether ligand 2, 2'-dinitro-4, 5, 4', 5'bis-(15-crown-5)-dihenzo disulfide(L) with trivalent rare earth nitrates having composition of RE(NO_3)_3·L·6H_2O(RE=Ce, Pr, Nd) have been synthesized in acetonitrile. All the isolated complexes have beencharacterized by elementary analysis, IR and UV spectra, differential thermal and thermogravimetricanalysis, X-ray powder diffraction analysis, molar conductance and measurements of solubility insome general solvents.     

APPLICATIONS OF DSCPCF MODEL IN RARE EARTH COMPLEXES(Ⅴ)——ANALYSIS OF SPECTRA OF THE NEODYMIUM AND ERBIUM TETR A (2-THENOYLTRIFLUOROACETONE) MONO PIPERIDINE COMPLEXES

The complexes, Nd(TTA)_4·HP and Er(TTA)_4·HP, have been prepared, and their UV-VIS-NIR absorption spectra measured. The matrix element expressions with J=1/2—15/2 of f~3 and f~(11) configurations in D_4 symmetry field were derived with the Double Sphere Coordination Point Charge Field Model. And the influence of change in symmetry of the complex unit REO_8 on splitting of their levels was discussed. Based on theoretical calculations, the absorption peaks in the spectra were assigned.     

STUDY OF THE INFLUENCE OF HUMIC SUBSTANCES ON THE SORPTION OF RARE EARTH ELEMENTS AT THE KAOLINITE AND BENTONITE SURFACES

ＳＴＵＤＹＯＦＴＨＥＩＮＦＬＵＥＮＣＥＯＦＨＵＭＩＣＳＵＢＳＴＡＮＣＥＳＯＮＴＨＥＳＯＲＰＴＩＯＮＯＦＲＡＲＥＥＡＲＴＨＥＬＥＭＥＮＴＳＡＴＴＨＥＫＡＯＬＩＮＩＴＥＡＮＤＢＥＮＴＯＮＩＴＥＳＵＲＦＡＣＥＳＤＵＪｉｎｚｈｏｕ；ＹＡＮＧＹｏｎｇｐｉｎｇ；...     

STUDIES ON DOPAMINE RECEPTORS AND TETRAHYDROPROTOBERBERINES．Ⅱ．QUANTUM CHEMISTRY OF LIGAND－RECEPTOR INTERACTION

ＳＴＵＤＩＥＳＯＮＤＯＰＡＭＩＮＥＲＥＣＥＰＴＯＲＳＡＮＤＴＥＴＲＡＨＹＤＲＯＰＲＯＴＯＢＥＲＢＥＲＩＮＥＳ．Ⅱ．ＱＵＡＮＴＵＭＣＨＥＭＩＳＴＲＹＯＦＬＩＧＡＮＤ－ＲＥＣＥＰＴＯＲＩＮＴＥＲＡＣＴＩＯＮ￥ＹｕｎＴＡＮＧ；ＫａｉＸｉａｎＣＨＥＮ；Ｈｕａ...     

STUDIES ON POLYMERIZATION MECHANISM OF CONJUGATED DIENE WITH η~3-ALLYL RARE EARTH MODEL COMPLEX

(η~-C_H_5)_2CeCl_5Mg_2(tmed)_2 was used as a catalyst to polymerizeisoprene,Terminal ends of polyisoprene were identified as -CH_2-CH=CH_,whichindicates that the insertion reaction of the monomer occurred between η~-allyland cerium ion and gives a direct evidence for the η~-allyl mechanism ofconjugated diene polymerzation with rare earth coordination catalysts.     

ADSORPTIVE BEHAVIOUR OF CARBOXYNITRAZO (CNA) AND ITS NEODYMIUM COMPLEX ON HANGING MERCURY DROP ELECTRODE~*

The adsorptive behaviour of CNA and Nd~(3+)-CNA complex has been studied by linear sweeping voltammetry. Some thermodynamic properties such as the surface concentration and the saturation adsorptive value of CNA on HMDE, the coverage area of one CNA molecule, the adsorption equilibrium constant, the adsorption free energy and the adsorption isotherm of CNA are reported in this paper. The percentages of complexed ligand CNA in total CNA reduced on HMDE with various Nd~(3+) concentrations have been estimated. The experimental facts support the adsorptive reduction meehanism of Nd~(3+)-CNA complex on HMDE.     

INFLUENCES OF LIGANDS ON THE HOMOGENEOUS HYDROFORMYLATION OF ALKENE(I)-TRI-(3,4-DIMETHYLPHENYL)PHOSPHITE AS A LIGAND

In this paper we describe the effects of tri(3, 4-dimethylphenyl)phosphite[(3,4-(CH_3)_2C_6H_3O)_3P]or triphenylphosphine(PPh_3)used as ligand in the homogeneoushydroformylation of alkene using dicarbonyl acetylacetone rhodium as the parent catalyst.The reaction kineties has been investigated.It was found that tri(3,4-dimethylphenyl)-phosphite has greater activity and better selcctivity than PPh_3 for hydroformylation ofheptene-1.The results are discussed in terms of eiectronic and stereochemical effects.     

BIBLIOGRAPHY OF CHIINESE RARE EARTH SCIENCE ANDTECHNOLOGY(1984)

p .APPlicationsD080 Effeets of rare earth on biologh,DingEnvironment Seienee,1984,5(2),70. Effeet of deformation on少eeiPitationandMa Huieha乒g,Journal ofD081strengthening for AI一Mg一51 alloy eontainingD082D083D084D085D086D087D088D089D090D091D092rare earth metals,Wang Shaoling etal.,Journal of Wuhan Ulllversity(Natural seien-ees adition),1984,4,44.1 Effeet of rare earth elements on ereep rupture in a niekel base alloy,Kong Gin-ping et al.,Iron and Steel,1984,19(1),41. Effeet of …     

STUDY ON POLYMER-RARE EARTH METAL ION COMPLEXES Ⅰ. FLUORESCENT PROPERTIES OF POLY(ACRYLIC ACID-CO-4-VINYLPYRIDINE)-RARE EARTH METAL COMPLEXES

A kind of copolymer of acrylic acid and vinylpyridine was synthesized and the fluorescent properties of the complexes of the copolymer with Eu~(3+) or Tb~(3+) were studied. It was found that the fluorescence intensity of the complexes of the eopolymer with Eu~(3+) was 20 times as high as that of the complexes of polyaerylic acid with Eu~(3+) and twice as high as that of the complexes of polyvinylpyridine with Eu~(3+). The effects of the composition of the copolymer and the content of Eu~(3+) or Tb~(3+) in the complexes were studied. The fluorescence lifetime of the complexes was measured and it was found that two or more kinds of energy transfer mechanism existed.     

STUDIES ON SCHIFF BASE COMPLEXES——Ⅳ. SYNTHESIS AND CRYSTAL STRUCTURE OF Fe (SALDPT) SAL

制备了Fe(saldpt)sal单晶并作了晶体结构分析。晶体数据:单斜,空间群P2_1/C(#14),a=12.486(5),b=18.502(8),c=10.870(5)A,β=104.23(3)°,V=2434(2)A~3,Z=4,D_c=1.40g/cm~3     

STUDIES ON SCHIFF BASE COMPLEXES——Ⅳ. SYNTHESIS AND CRYSTAL STRUCTURE OF Fe (SALDPT) SAL

制备了Fe(saldpt)sal单晶并作了晶体结构分析。晶体数据:单斜,空间群P2₁/C(#14),a=12.486(5),b=18.502(8),c=10.870(5)Å,β=104.23(3)°,V=2434(2)ų,Z=4,D_c=1.40g/cm³.