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1988 Volume 5 Issue 5
1988, 5(5): 1-9
Abstract:
Principles of writing,reading,and erasing for the optical memory disk are introduced and the new trends of research focus and related techniques are discussed in this review. The erasable optical disk with high recording density,high stability,high data transfer rate, high carrier-noise ratio and low error rate arc the main points in the research and development.
Principles of writing,reading,and erasing for the optical memory disk are introduced and the new trends of research focus and related techniques are discussed in this review. The erasable optical disk with high recording density,high stability,high data transfer rate, high carrier-noise ratio and low error rate arc the main points in the research and development.
1988, 5(5): 10-15
Abstract:
The thermal decomposition of pentacyanoferratecomplexes Nax[Fe(CN)5L]·yH2O (L=NO+,N2H5+,enH+,NH3,H2O,pyridine,SO3) in vacuum has been investigated by quadrupole mass spectrometry as well as Mssbauer spectroscopy to detect the intermediate solid products during the decomposition.The mechanism of thermal decomposition is eluci-dated and it is found that the thermal stability of these complexes was ordered in accordance with the spectrochemieal series.Kinetic study on the decomposition showed that there is a linear relationship between the decomposition activation energies and the temperatures at which the ligand L lost.
The thermal decomposition of pentacyanoferratecomplexes Nax[Fe(CN)5L]·yH2O (L=NO+,N2H5+,enH+,NH3,H2O,pyridine,SO3) in vacuum has been investigated by quadrupole mass spectrometry as well as Mssbauer spectroscopy to detect the intermediate solid products during the decomposition.The mechanism of thermal decomposition is eluci-dated and it is found that the thermal stability of these complexes was ordered in accordance with the spectrochemieal series.Kinetic study on the decomposition showed that there is a linear relationship between the decomposition activation energies and the temperatures at which the ligand L lost.
1988, 5(5): 16-20
Abstract:
The relaxation spectra of a set of star-shaped polystyrenes with the equal length of arms but different branching degree were determined by means of a stress relaxation instru-ment.The effect of branching structure on the rubbery plateau in the relaxation spectra was investigated,and the relaxation spectra were computer simulated using a "tube" model.The difference in viscoelastic properties of star-shaped polystyrenes were interpreted in terms of molecular motion.
The relaxation spectra of a set of star-shaped polystyrenes with the equal length of arms but different branching degree were determined by means of a stress relaxation instru-ment.The effect of branching structure on the rubbery plateau in the relaxation spectra was investigated,and the relaxation spectra were computer simulated using a "tube" model.The difference in viscoelastic properties of star-shaped polystyrenes were interpreted in terms of molecular motion.
1988, 5(5): 21-24
Abstract:
A novel type of gassensitive electrode,a gas thin-layer electrode(GTLE),has been con-structed by using hydrophobic gas diffusing electrode technique.Distinctive peaks appeared on linear sweep voltammetry curves as the result of exhaustive electrolysis of reactants within GTLE.The charge(Qp) correlated to the current peak was directly proportional to the amount of the reactant component in the pores of GTLE,thus its concentration in the gas sample can be detected. The measuring system is simple in construction,capable of fast sampling(<5S),with lower temperature coefficient(-0.1-0.3%/℃),high sensitivity and good stability.
A novel type of gassensitive electrode,a gas thin-layer electrode(GTLE),has been con-structed by using hydrophobic gas diffusing electrode technique.Distinctive peaks appeared on linear sweep voltammetry curves as the result of exhaustive electrolysis of reactants within GTLE.The charge(Qp) correlated to the current peak was directly proportional to the amount of the reactant component in the pores of GTLE,thus its concentration in the gas sample can be detected. The measuring system is simple in construction,capable of fast sampling(<5S),with lower temperature coefficient(-0.1-0.3%/℃),high sensitivity and good stability.
1988, 5(5): 25-29
Abstract:
Themicrophotographs showed that the emulsion of the acrylate-vinyl acetate copolymer posse-ssedcore-shell structure.When different feed ratio was used the monomer predominantin fee-ding comprised core,by using various means of feeding the monomer first added polymerized and formed core first.The microstructure showed obvious effect on the mechanical properties,Tg and water-resistance of the latex film cast from the emulsion.Based on the study on the microstructure of emulsion particle it is considered that when the content of vinyl acetate was more than 50mol% in feeding the initiation and nuclei formation of the copolymerization proceeded in water phase.
Themicrophotographs showed that the emulsion of the acrylate-vinyl acetate copolymer posse-ssedcore-shell structure.When different feed ratio was used the monomer predominantin fee-ding comprised core,by using various means of feeding the monomer first added polymerized and formed core first.The microstructure showed obvious effect on the mechanical properties,Tg and water-resistance of the latex film cast from the emulsion.Based on the study on the microstructure of emulsion particle it is considered that when the content of vinyl acetate was more than 50mol% in feeding the initiation and nuclei formation of the copolymerization proceeded in water phase.
1988, 5(5): 30-33
Abstract:
The N-or P-coordinated complexes of monoalkyl carboxyl and sulfonyl titanate were prepared.By means of XPS the N→Ti or P→Ti coordination bonds in these complexes were ascertained,and the relative bonding strength were estimated from the magnitude of the chemical shift data.The sulfonyl titanates are easier to be coordinated with N or P ligands, than the carboxyl titanates;and the hydroxysubstituted amines were coordinated easily with titanates;The chemical shifts of P-coordinated complexes were not pronounced as in the com-plexes with N-ligands.It may be caused by the "back donation" of Ti→P in these complexes. In addition,The intra-molecular N→Ti coordinate linkage has also been identified in the reaction products of isopropyl titanate and ethyl hydroxyl amines.
The N-or P-coordinated complexes of monoalkyl carboxyl and sulfonyl titanate were prepared.By means of XPS the N→Ti or P→Ti coordination bonds in these complexes were ascertained,and the relative bonding strength were estimated from the magnitude of the chemical shift data.The sulfonyl titanates are easier to be coordinated with N or P ligands, than the carboxyl titanates;and the hydroxysubstituted amines were coordinated easily with titanates;The chemical shifts of P-coordinated complexes were not pronounced as in the com-plexes with N-ligands.It may be caused by the "back donation" of Ti→P in these complexes. In addition,The intra-molecular N→Ti coordinate linkage has also been identified in the reaction products of isopropyl titanate and ethyl hydroxyl amines.
1988, 5(5): 34-38
Abstract:
Polyester-polyether multiblock copolymers with relatively high content of hard segment and molecular weight of soft segment exhibit low compositional homogeneity and a large amount of CHCl3 insoluble fraction with high melting point can be separated out.The addition of 5% mol of dimethyl isophthalate(DMI) as a comonomer during ester exchange reaction much improves the apparent compositional homogeneity of the multiblock copolymers. The polyethylene terephthalate-polyethylene glycol ether multiblock copolymers(PET-PEG) with hard segment of 40 wt% and PEG molecular weight of 4000 were synthesized with excellent mechanical properties and no CHCl3 insoluble fraction.An alternative synthetic route has also been explored,according to which the PET is first acidolysed by isophthalic acid(IPA)and then copolycondensized with OH-terminated PEG to prepare PET-PEG with isophthalate units in hard segments.The compositional homogeniety of PET-PEG obtained greatly increases as the molecular weight of PEG decreases.
Polyester-polyether multiblock copolymers with relatively high content of hard segment and molecular weight of soft segment exhibit low compositional homogeneity and a large amount of CHCl3 insoluble fraction with high melting point can be separated out.The addition of 5% mol of dimethyl isophthalate(DMI) as a comonomer during ester exchange reaction much improves the apparent compositional homogeneity of the multiblock copolymers. The polyethylene terephthalate-polyethylene glycol ether multiblock copolymers(PET-PEG) with hard segment of 40 wt% and PEG molecular weight of 4000 were synthesized with excellent mechanical properties and no CHCl3 insoluble fraction.An alternative synthetic route has also been explored,according to which the PET is first acidolysed by isophthalic acid(IPA)and then copolycondensized with OH-terminated PEG to prepare PET-PEG with isophthalate units in hard segments.The compositional homogeniety of PET-PEG obtained greatly increases as the molecular weight of PEG decreases.
1988, 5(5): 39-43
Abstract:
A porous Ni/Al2O3 catalyst plate was prepared.It gives NH3 conversion more than 99.5% at 750℃ and space velocity of NH3 10000-40000h1-.An internal heating type was adopted Which saves 30% energy in comparison with the external heating type.The results of reaction kinetics showed that the rate equation of ammonia decomposition on the catalyst plate is γ=kP2NH3 and the apparent activation energy is 153.0kJ/mol. The partial oxidation of ammonia on the catalyst plate was also investigated at the con-ditions of 680-750℃,air/NH3=1.7-1.0 and space velocity 10000-40000h-1.The results showed that a gas mixture containing 30-43% of H2 and less 0.1% of O2 was obtained without external heating after NH3 combustion.A duration test for 250h indicated that NH3 conversion was over 99.5%.The reaction kinetics showed that the rate equation of partial oxidation of ammonia was of zero order and the apparent activation energy obtained was 37.2kJ/mol.
A porous Ni/Al2O3 catalyst plate was prepared.It gives NH3 conversion more than 99.5% at 750℃ and space velocity of NH3 10000-40000h1-.An internal heating type was adopted Which saves 30% energy in comparison with the external heating type.The results of reaction kinetics showed that the rate equation of ammonia decomposition on the catalyst plate is γ=kP2NH3 and the apparent activation energy is 153.0kJ/mol. The partial oxidation of ammonia on the catalyst plate was also investigated at the con-ditions of 680-750℃,air/NH3=1.7-1.0 and space velocity 10000-40000h-1.The results showed that a gas mixture containing 30-43% of H2 and less 0.1% of O2 was obtained without external heating after NH3 combustion.A duration test for 250h indicated that NH3 conversion was over 99.5%.The reaction kinetics showed that the rate equation of partial oxidation of ammonia was of zero order and the apparent activation energy obtained was 37.2kJ/mol.
1988, 5(5): 44-47
Abstract:
Polybutadiene-b-polyisoprene diblock copolymer(PB-b-PI) was synthesized using anionic polymerization initiated by n-butyllithium.PB segment in it was then uniquely hydrogenated in the presence of cobalt 2-ethylhexanoate/triethylaluminium catalyst,giving poly ethylene-b-polyisoprene diblock copolymer(PE-b-PI).The two diblock copolymers were characterized by infrared analysis,GPC,viscosity,DSC,x-ray diffraction and dynamic mechanical measurements.
Polybutadiene-b-polyisoprene diblock copolymer(PB-b-PI) was synthesized using anionic polymerization initiated by n-butyllithium.PB segment in it was then uniquely hydrogenated in the presence of cobalt 2-ethylhexanoate/triethylaluminium catalyst,giving poly ethylene-b-polyisoprene diblock copolymer(PE-b-PI).The two diblock copolymers were characterized by infrared analysis,GPC,viscosity,DSC,x-ray diffraction and dynamic mechanical measurements.
1988, 5(5): 48-52
Abstract:
The effects of the secondary additives on the rate of solvent evaporation and the performance of PVC UF membrane were investigated.It is found that the sort and content of secondary additives can influence on both the value of evaporation rate constant b and the membrane performances.The greater the difference between secondary additive and solvent, and the higher the content of secondary additive,the more remarkable change in the value of b.In the conditions used,the maximum flux value appears at 5%(wt) of secondary additive in the casting solution.Moreover,the evaporation time also has an important influence on the formation of polymer network pores and polymer aggregate pores,along with their size and the size distribution.
The effects of the secondary additives on the rate of solvent evaporation and the performance of PVC UF membrane were investigated.It is found that the sort and content of secondary additives can influence on both the value of evaporation rate constant b and the membrane performances.The greater the difference between secondary additive and solvent, and the higher the content of secondary additive,the more remarkable change in the value of b.In the conditions used,the maximum flux value appears at 5%(wt) of secondary additive in the casting solution.Moreover,the evaporation time also has an important influence on the formation of polymer network pores and polymer aggregate pores,along with their size and the size distribution.
1988, 5(5): 53-57
Abstract:
Poly(vinyl acetate)/poly(methacrylate) interpenetrating polymer networks(PVAc/PMA IPNs) and semi-IPNs were swollen in toluene under the thermodynamic condition of phase separation,or the PVAc component of the IPNs was alcoholyzed to decrease the compatibi-lity between two components.No phase separation was found in IPNs and semi-IPNs with high crosslink density of network I.It is indicated that the mutual entanglements between the two networks is permanent physical entanglements and the phase of the IPNs is stable.
Poly(vinyl acetate)/poly(methacrylate) interpenetrating polymer networks(PVAc/PMA IPNs) and semi-IPNs were swollen in toluene under the thermodynamic condition of phase separation,or the PVAc component of the IPNs was alcoholyzed to decrease the compatibi-lity between two components.No phase separation was found in IPNs and semi-IPNs with high crosslink density of network I.It is indicated that the mutual entanglements between the two networks is permanent physical entanglements and the phase of the IPNs is stable.
1988, 5(5): 58-62
Abstract:
XPS studies show that carbonates are formed on the surfaces of Y2O3,BaO,CuO and YBa2Cu3O~7 superconductor therefrom stored in air.The valence states of the elements on the surface of the superconductor are follows:Y3+,Ba2+ and Cu2+.Individual raw CuO can be converted mostly into Cu2O after heating at 400℃ under high vacuum,while in newly prepared superconductor at the same conditions only a small portion of Cu2+ ions are converted to Cu1+ ions.These results indicate that sintering enhanced the stability of Y-Ba-Cu-Osystem. However,for the superconductor stored long in air this conversion of Cu2+ to Cu1+ takes place readily,which reflects that the"ceramic superconductor"does not behave as a true ceramic in stability,it still shows a "metastable" feature.
XPS studies show that carbonates are formed on the surfaces of Y2O3,BaO,CuO and YBa2Cu3O~7 superconductor therefrom stored in air.The valence states of the elements on the surface of the superconductor are follows:Y3+,Ba2+ and Cu2+.Individual raw CuO can be converted mostly into Cu2O after heating at 400℃ under high vacuum,while in newly prepared superconductor at the same conditions only a small portion of Cu2+ ions are converted to Cu1+ ions.These results indicate that sintering enhanced the stability of Y-Ba-Cu-Osystem. However,for the superconductor stored long in air this conversion of Cu2+ to Cu1+ takes place readily,which reflects that the"ceramic superconductor"does not behave as a true ceramic in stability,it still shows a "metastable" feature.
1988, 5(5): 63-66
Abstract:
The investigation of a reversible reaction at disk microelectrode by deeonvolution voltammetry including semi-(e),1.5th(e')and 2.5th(e″) differential voltammetry is presented. The peak shape of e-E curve is similar to the voltammgram obtained at conventional electrode.The relationship between the peak height of e,e'or e″ and scan rate shows 0,5,1.5 and 2.5 order at disk microelectrode respectively,0.5 order lower than that at HMDE,The advantage of using microelectrode in deconvolution voltammetry is high sensitivity and selectivity,The behavior of a redox reaction at disk microelectrode by phase-selective AC voltammetry for the first and second harmonics is also described.
The investigation of a reversible reaction at disk microelectrode by deeonvolution voltammetry including semi-(e),1.5th(e')and 2.5th(e″) differential voltammetry is presented. The peak shape of e-E curve is similar to the voltammgram obtained at conventional electrode.The relationship between the peak height of e,e'or e″ and scan rate shows 0,5,1.5 and 2.5 order at disk microelectrode respectively,0.5 order lower than that at HMDE,The advantage of using microelectrode in deconvolution voltammetry is high sensitivity and selectivity,The behavior of a redox reaction at disk microelectrode by phase-selective AC voltammetry for the first and second harmonics is also described.
1988, 5(5): 67-70
Abstract:
The cyclic voltammetric properties of a series of double-pseudo-cubane cluster compounds (Et4N)4[Mo2Fe7S8(SR)12](R=Ph,1;R=o-tolyl,2;R=m-tolyl,3;R=P-tolyl,4)were studied in 0--2.0V vs.SCE.All the compounds showed two redox couples corresponding to the single-electron rcdox reaction of two [MoFe3S4]3+ cubanc cores respectively.Möss-bauer spectrum of 3·2THF recorded at liquid nitrogen temperature indicates the existence of three types of Fe site in the compound.They are four coordinate 2Fe(Ⅲ)+Fe(Ⅱ)of high spin in the[MoFe3S4]3+ core with average oxidation state of Fe at+2.67 and six-coordinate Fe(Ⅱ) of high spin in Fe(SR)6 bridge.
The cyclic voltammetric properties of a series of double-pseudo-cubane cluster compounds (Et4N)4[Mo2Fe7S8(SR)12](R=Ph,1;R=o-tolyl,2;R=m-tolyl,3;R=P-tolyl,4)were studied in 0--2.0V vs.SCE.All the compounds showed two redox couples corresponding to the single-electron rcdox reaction of two [MoFe3S4]3+ cubanc cores respectively.Möss-bauer spectrum of 3·2THF recorded at liquid nitrogen temperature indicates the existence of three types of Fe site in the compound.They are four coordinate 2Fe(Ⅲ)+Fe(Ⅱ)of high spin in the[MoFe3S4]3+ core with average oxidation state of Fe at+2.67 and six-coordinate Fe(Ⅱ) of high spin in Fe(SR)6 bridge.
1988, 5(5): 71-73
Abstract:
The behaviors of three supported coordination catalysts,PdCl2-Tussah silk,PdCl2-PVP(polyvinylpyrrolidone),PdCl2-PVP/Al2O3 in the hydrogenation of 1-hexene,1-decone,2-ethyl-hexene,crotonaldehyde,cinnamaldehyde and cyclododecatriene were inve-stigated,the activities of these substrates were different from catalyst to catalyst.The hydrogenation rates of the substrates with large space hindranceover PdCl2-PVP catalyst were higher than that over PdCl2-Tussah silk catalyst.The larger the space hindrance disparity,the more the difference between the activities of these two catalysts.Most of the substrates show higher activities in reaction over PdCl2-PVP/Al2O3.The hydrogenation selectivities were also different for different catalysts.
The behaviors of three supported coordination catalysts,PdCl2-Tussah silk,PdCl2-PVP(polyvinylpyrrolidone),PdCl2-PVP/Al2O3 in the hydrogenation of 1-hexene,1-decone,2-ethyl-hexene,crotonaldehyde,cinnamaldehyde and cyclododecatriene were inve-stigated,the activities of these substrates were different from catalyst to catalyst.The hydrogenation rates of the substrates with large space hindranceover PdCl2-PVP catalyst were higher than that over PdCl2-Tussah silk catalyst.The larger the space hindrance disparity,the more the difference between the activities of these two catalysts.Most of the substrates show higher activities in reaction over PdCl2-PVP/Al2O3.The hydrogenation selectivities were also different for different catalysts.
1988, 5(5): 74-77
Abstract:
Atomic and ionic fluorescences of barium have been studied using a CW dye laser for excitation and a hoUow cathode lamp as an atomizer.The types of atomic and ionic fluo-rescences were measured.An anomalous negative signal was observed and discussed briefly.
Atomic and ionic fluorescences of barium have been studied using a CW dye laser for excitation and a hoUow cathode lamp as an atomizer.The types of atomic and ionic fluo-rescences were measured.An anomalous negative signal was observed and discussed briefly.
1988, 5(5): 78-81
Abstract:
Bis(6-bromo-9-ethyl-carbazole-3-yl) toluene-iodide is synthesized and verified by IR, NMR,MS and elemental analysis.The dye would be a good sensitizer for organic photo-conductors by preliminary experiments.
Bis(6-bromo-9-ethyl-carbazole-3-yl) toluene-iodide is synthesized and verified by IR, NMR,MS and elemental analysis.The dye would be a good sensitizer for organic photo-conductors by preliminary experiments.
1988, 5(5): 82-85
Abstract:
The permeability coefficient(Pg) of polyurethane(PU) with polybutylene adipate(PBA) or polypropylene glycol(PPG) as soft segment has been investigated.Both the types and length of the soft segment have great effect upon the gas permeability.PU with PPG seg-ment shows higher gas permeability than that with PBA segment,Increasing the soft seg-ment length brings about an increase in gas permeability and a decrease in the apparent activation energy. The linear relationship between Pg and the composition of the mixed soft segments indicates that the permeability coefficients of PU with PBA and PPG as soft segment are additive.
The permeability coefficient(Pg) of polyurethane(PU) with polybutylene adipate(PBA) or polypropylene glycol(PPG) as soft segment has been investigated.Both the types and length of the soft segment have great effect upon the gas permeability.PU with PPG seg-ment shows higher gas permeability than that with PBA segment,Increasing the soft seg-ment length brings about an increase in gas permeability and a decrease in the apparent activation energy. The linear relationship between Pg and the composition of the mixed soft segments indicates that the permeability coefficients of PU with PBA and PPG as soft segment are additive.
1988, 5(5): 86-89
Abstract:
In this paper polyethylene(PE) and chlorinated polyethylene(CPE) from solid-phase chlorination were studied by the variance method in x-ray diffractometer.After the deduc-tion of back ground and the corrections for Kαdoublet and the broadening of the instrument, the crystallite sizes and degrees of lattice distortion in PE and CPE were obtained.The results show that(1) With the aid of microcomputer,the method of variance-range function can be used for determining the crystallite size and degree of lattice distortion in poly-mer;(2) In CPE the crystallite size decreases and the degree of lattice distortion increases with increase of chlorine content when the later is≤12.0% in the polymer.
In this paper polyethylene(PE) and chlorinated polyethylene(CPE) from solid-phase chlorination were studied by the variance method in x-ray diffractometer.After the deduc-tion of back ground and the corrections for Kαdoublet and the broadening of the instrument, the crystallite sizes and degrees of lattice distortion in PE and CPE were obtained.The results show that(1) With the aid of microcomputer,the method of variance-range function can be used for determining the crystallite size and degree of lattice distortion in poly-mer;(2) In CPE the crystallite size decreases and the degree of lattice distortion increases with increase of chlorine content when the later is≤12.0% in the polymer.
1988, 5(5): 90-92
Abstract:
Using urea,acetic acid and phosphorus trichloride as raw materials,ammonium salt of 1-aminocthylidenediphosphonic acid(NH,AEDP) has been synthesized with yield of 40%. The scale and corrosion inhibition tests of AEDP and HEDP(1-hydroxycthylidenediphos-phonic acid) showed that AEDP is better than HEDP.
Using urea,acetic acid and phosphorus trichloride as raw materials,ammonium salt of 1-aminocthylidenediphosphonic acid(NH,AEDP) has been synthesized with yield of 40%. The scale and corrosion inhibition tests of AEDP and HEDP(1-hydroxycthylidenediphos-phonic acid) showed that AEDP is better than HEDP.
1988, 5(5): 93-95
Abstract:
In this paper the output characteristics of PEC cell based on n-GaAs are studied.The influences of light intensity,chemical etching,concentration of redox system and ion modification on the conversion efficiency of PEC cell are observed.The conversion efficiency reaches 23.9% when the light intensity is low(9.61mW.cm-2),with the electrode being repeatedly etched and modified by Ni2+ ion.The effect of pH on the flatband potential is determined.
In this paper the output characteristics of PEC cell based on n-GaAs are studied.The influences of light intensity,chemical etching,concentration of redox system and ion modification on the conversion efficiency of PEC cell are observed.The conversion efficiency reaches 23.9% when the light intensity is low(9.61mW.cm-2),with the electrode being repeatedly etched and modified by Ni2+ ion.The effect of pH on the flatband potential is determined.
1988, 5(5): 96-99
Abstract:
A sensitive and accurate method for trace determination of Cr(Ⅲ) as well as Cr(Ⅵ) is proposed in which Cr(Ⅵ) is extracted by tri-n-butylphosphate(TBP) and analyzed by flame atomic absorption spectrophotometry.The presence of Cr(Ⅲ),with its concentration up to 500-fold to Cr(Ⅵ),does not affect the result.In the method,Cr(Ⅲ) is oxidized to Cr(Ⅵ) by KMnO4 at 100℃ in H2SO4 solution using CO(NH2)2 as a protection agent, and then determined by subtraction of the original Cr(Ⅵ) content from the total Cr (Ⅵ) content.Samples of drinking water and water from Huang-Pu River were determined for Cr(Ⅲ) and Cr(Ⅵ).The results was satisfied,It is considered that the sensitivity of the method lies on the formation of a solvation compound Cr(Ⅵ)-TBP-Cl-.
A sensitive and accurate method for trace determination of Cr(Ⅲ) as well as Cr(Ⅵ) is proposed in which Cr(Ⅵ) is extracted by tri-n-butylphosphate(TBP) and analyzed by flame atomic absorption spectrophotometry.The presence of Cr(Ⅲ),with its concentration up to 500-fold to Cr(Ⅵ),does not affect the result.In the method,Cr(Ⅲ) is oxidized to Cr(Ⅵ) by KMnO4 at 100℃ in H2SO4 solution using CO(NH2)2 as a protection agent, and then determined by subtraction of the original Cr(Ⅵ) content from the total Cr (Ⅵ) content.Samples of drinking water and water from Huang-Pu River were determined for Cr(Ⅲ) and Cr(Ⅵ).The results was satisfied,It is considered that the sensitivity of the method lies on the formation of a solvation compound Cr(Ⅵ)-TBP-Cl-.
