A new reagent 2-QADN2,7 has been synthesized and its electroana- lytical characteristics have been studied.The procedure of the adsorptive voltammetric determination of copper,nickel,cohalt and cadmium was worked out.
In this work, a flow injection analysis (FIA) method for the trace determination of lead, cadmium, nickel and cobalt in natural waters by formation of neutral chelates with ammonium pyrrolidine dithiocarbamate (APDC) ...In this work, a flow injection analysis (FIA) method for the trace determination of lead, cadmium, nickel and cobalt in natural waters by formation of neutral chelates with ammonium pyrrolidine dithiocarbamate (APDC) was developed. The neutral chelates formed was retained in a mini-column packed with Linde type A zeolite (LTA) and type Y Faujasite zeolite (FAU) and then eluted with methyl isobutyl ketone (MIBK) to flame atomic absorption spectrometry (EAA) for its detection. Physicochemical characterization of this zeolite was carried out by Fourier Transform infrared spectroscopy and attenuated total reflectance (FTIR and IR-ATR), scanning electron microscopy and energy dispersive X-ray microanalysis (SEM-EDX) and X-ray power diffraction (XRD). Then, a FIA configuration was used with a column preconcentration system coupled to the detection system at room temperature (22?C). The detection limit and the relative standard deviation for 5 determinations of different solutions of Pb2+, Co2+, Ni2+ and Cd2+ for FAU and LTA zeolite were calculated. The sampling frequency ranged from 18-35 h-1 and preconcentration factors from 21-250 were achieved, for a sample volume of 6 mL using 20 mg of sorbents, indicating a high retention of the analytes on the zeolites material. The recoveries obtained in natural waters samples were close to 100% for all ions metal using synthetic zeolites, confirming the applicability of the method. The isotherm models of Langmuir, Scatchard, Freundlich and Dubinin-Radushkevich were used to study the equilibrium data, indicating that successfully followed the Freundlich and Dubinin-Radushkevich (D-R) isotherms at low metal ion concentration. The Freundlich parameter n varied between 0.35-1.01, whereas D-R isotherm yields the sorption free energy E 8 kJ.mol-1 indicating psysisorption.展开更多
The simultaneous determination of cobalt, copper and nickel using 1-(2-thiazolylazo)-2-naphthol (first figure of this article) by spectrophotometric method is a difficult problem in analytical chemistry, due to sp...The simultaneous determination of cobalt, copper and nickel using 1-(2-thiazolylazo)-2-naphthol (first figure of this article) by spectrophotometric method is a difficult problem in analytical chemistry, due to spectral interferences. By multivariate calibration methods, such as partial least squares (PLS) regression, it is possible to obtain a model adjusted to the concentration values of the mixtures used in the calibration range. Orthogonal signal correction (OSC) is a preprocessing technique used for removing the information unrelated to the target variables based on constrained principal component analysis. OSC is a suitable preprocessing method for PLS calibration of mixtures without loss of prediction capacity using spectrophotometric method. In this study, the calibration model is based on absorption spectra in the 550-750-nm range for 21 different mixtures of cobalt, copper and nickel. Calibration matrices were formed from samples containing 0.05-1.05, 0.05-1.30 and 0.05-0.80 μg·mL^-1 for cobalt, copper and nickel, respectively. The root mean square error of prediction (RMSEP) for cobalt, copper and nickel with OSC and without OSC were 0.007, 0.008, 0.011 and 0.031,0.037, 0.032 μg· mL^-1, respectively. This procedure allows the simultaneous determination of cobalt, copper and nickel in synthetic and real samples and good reliability of the determination was proved.展开更多
A number of synergistic solvent extraction (SSX) systems have been developed to recover nickel, cobalt, zinc and copper from sulphuric and chloride leach solutions by the solvent extraction team of CSIRO, Australia....A number of synergistic solvent extraction (SSX) systems have been developed to recover nickel, cobalt, zinc and copper from sulphuric and chloride leach solutions by the solvent extraction team of CSIRO, Australia. These in- clude (1) Versatic 10/CLXS0 system for the separation of Ni from Ca in sulphate solutions, (2) Versatic 10/4PC system for the separation of Ni and Co from Mn/Mg/Ca in sulphate solutions, (3) Cyanex 471X/HRJ-4277 system for the separation of Zn from Cd in sulphate solutions, (4) Versatic 10/LIX63 system for the separation of Co from Mn/Mg/Ca in sulphate solutions, (5) Versatic 10/LIX63/TBP system for separation of Ni and Co from Mn/Mg/Ca in sulphate solutions, (6) Versatic 10/LIX63 system for the separation of cobalt from nickel in sulphate solutions by difference in kinetics, (7) Cyanex 272/LIX84 system for the separation of Cu/Fe/Zn from Ni/Co in sulphate solutions, (8) Versatic 10/LIX63fFBP system to recover Cu/Ni from strong chloride solutions, and [9) Versatic 10/LIX63 system to separate Cu from Fe in strong chloride solutions. The synergistic effect on metal separation and efficiency is presented and possible industrial applications are demonstrated. The chemical stability of selected SSX systems is also reported.展开更多
Nickel, cobalt and copper were separated by solvent extraction with P204. The experimental results show that [Co(NH 3) 6] 3+ is an inert complex in extraction kinetics, therefore cobalt can be separated from nickel an...Nickel, cobalt and copper were separated by solvent extraction with P204. The experimental results show that [Co(NH 3) 6] 3+ is an inert complex in extraction kinetics, therefore cobalt can be separated from nickel and copper by non equilibrium solvent extraction. Under the conditions of temperature 25?℃, contact time of two phases 10?min, phase ratio 1∶1, aqueous pH 10.10 and concentration of P204 20%, [Co(NH 3) 6] 3+ is hardly extracted by P204, while the percentage extractions of nickel and copper are 79.3% and 93.9% respectively. Nickel and copper are separated by equilibrium solvent extraction with P204. Under the conditions of temperature 25?℃, contact time of two phases 1?min, phase ratio 1∶1, equilibrium pH 4.01 and concentration of P204 20%, the separation factor of copper and nickel is 216.展开更多
A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone(2-PYAINH) was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At ...A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone(2-PYAINH) was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At a pH value of 7.0, 9,0, 9.0, and 8.0, respectively, which greatly increased the selectivity; nickel, copper, cobalt, and iron reacted with 2-PYAINH to form a 1:2 yellow-orange, 1:2 yellow-green, 1:2 yellow and 1:1 yellow complexes, with absorption peaks at 363, 352, 346, and 359 nm, respectively. Under the optimal conditions, Beer's law was obeyed over the ranges of 0.01-1.4, 0.01-1.5, 0.01-2.7, and 0.01-5.4 mg/L respectively. The apparent molar absorptivity and Sandell's sensitivities were 8.4×10^4, 5.2×10^4, 7.1×10^4, and 3.9×10^4 L·mol^-l·cm^-1, respectively, and 0.00069, 0.0012, 0.00078, and 0.0014 μg·cm2, respectively. The detection limits were found to be 0.001, 0.002, 0.003, and 0.01 mg/L, respectively. The detailed study of various interfering ions to make the method more sensitive was carried out and selective and several real samples were analyzed with satisfactory results.展开更多
A new Schiff base (LK) obtained from 2, 4, -dihydroxybenzaldehyde and glycly-DL- phenylalanine reacted with Cu(II), Zn(II), Ni(II) and Co(II) to yield new complexes. The complexes were characterized by elemental an...A new Schiff base (LK) obtained from 2, 4, -dihydroxybenzaldehyde and glycly-DL- phenylalanine reacted with Cu(II), Zn(II), Ni(II) and Co(II) to yield new complexes. The complexes were characterized by elemental analyses, molar conductance, 1H NMR DTA, TG, IR and UV spectroscopy. In these complexes the ligand is coordinated to the metal through its phenolic oxygen, carboxyl oxygen, imino nitrogen and amide nitrogen. All complexes are non-electrolytes and four coordinated with 1:1(metal; ligand) stoichiometry. The probable structure of the complexes is suggested展开更多
Mononuclear copper(Ⅱ), nickel(Ⅱ) and cobalt(Ⅲ) tetracoordinate macrocyclic complexes were synthesized and spectroscopically characterized. The crystal structure of the three compounds were determined by X-ray...Mononuclear copper(Ⅱ), nickel(Ⅱ) and cobalt(Ⅲ) tetracoordinate macrocyclic complexes were synthesized and spectroscopically characterized. The crystal structure of the three compounds were determined by X-ray crystallography. The electrochemical experimental results indicate that the three complexes could interact with DNA mainly by electrostatic interaction. The interaction of tetracoordinate macrocyclic cobalt(Ⅲ) complex with DNA was studied by cyclic voltammetry and UV-vis spectroscopy. The experimental results reveal that tetracoordinate macrocyc- lic cobalt(Ⅲ) complex could interact with DNA by electrostatic interaction to form a 1 : 1 DNA association complex with a binding constant of 7.50 ×10^3 L·mol^-1.展开更多
Aim: To determine the seminal concentrations of copper, zinc, iron, cadmium, lead and nickel in bulls, rams, boars, stallions and foxes and study their correlations. Methods: Semen samples were obtained, digested and ...Aim: To determine the seminal concentrations of copper, zinc, iron, cadmium, lead and nickel in bulls, rams, boars, stallions and foxes and study their correlations. Methods: Semen samples were obtained, digested and analyzed by means of the atomic absorption spectrophotometer. Data were analyzed statistically with the Student's t-test and Scheffe's test using PC programs SAS and Excel. Results: The seminal copper concentration was significantly higher in ram [(2.49±0.18) mg/kg] and fox [(2.16±0.53) mg/kg] than that in bull [(1.64±0.21) mg/kg], boar [(1.64±0.28) mg/kg] and stallion (0.86 mg/kg). In boar a significantly higher seminal zinc concentration (171.74±65.72) mg/kg] was found in comparison with stallion [(86.20±45.88) mg/kg], bull [(83.15±61.61) mg/kg], ram [( 60.46±35.37) mg/kg] and fox (13.09±5.22) mg/kg]. The iron concentration in semen was significantly higher in ram [(40.32±10.81) mg/kg), bull [(38.04±22.07) mg/kg] and fox [(33.16±24.36) mg/kg] than that in boar [(16.14±10.35) mg/kg] and stallion (12.68 mg/kg). The seminal cadmium concentration was relatively low [(0.05-0.12) mg/kg] in all studied species. The seminal lead concentration was the highest in ram [(0.35±0.68) mg/kg], which was much higher than in fox [(0.08±0.06) mg/kg], bull [(0.06±0.04) mg/kg], stallion [(0.05±0.05) mg/kg] and boar [0.02±0.03) mg/kg]. The level of seminal nickel was significantly higher in fox [(0.35±0.24) mg/kg] and ram [(0.31±0.19) mg/ kg] in comparison with bull [(0.12±0.07) mg/kg] and boar [(0.06±0.08) mg/kg]. The concentration of nickel in the semen of stallion was (0.20±0.24) mg/kg. There was a high positive correlation between seminal iron and zinc in bull (r=0.723) and stallion (r=0.723), between cadmium and lead in ram (r=0.976) and boar (r=0.973) and between iron and cadmium (r=0.783) and iron and lead (r=0.791) in boar. A high negative correlation between seminal nickel and copper in ram (r=-0.709) and between seminal copper and lead in fox (r=-0.854) was found. Conclusion: There are significant differences in the concentrations of seminal elements in different animals. There is a high concentration of seminal copper in ram and fox, a high zinc level in boar, a high iron level in bull, ram and fox and a high nickel level in ram and fox.展开更多
Simultaneous determination of impurity metal ions in high concentration zinc solution is very important for zinc hydrometallurgy,and the purpose is to establish a method for determining the trace Cu^2+,Cd^2+,Ni^2+and ...Simultaneous determination of impurity metal ions in high concentration zinc solution is very important for zinc hydrometallurgy,and the purpose is to establish a method for determining the trace Cu^2+,Cd^2+,Ni^2+and Co^2+in zinc electrolytes at the same time using the second derivative waves of single sweep oscillopolarography.Factors affecting the derivative waves of the ions were researched in a medium of dimethylglyoxime(DMG)-sodium citrate-sodium tetraborate.The results indicated that the interferences of a high concentration of Zn^2+and most other coexisting ions on the determination can be eliminated;when the Cu^2+,Cd^2+,Ni^2+and Co^2+are in the ranges of1×10^-7-3×10^-4,6×10^-7-2×10^-4,2×10^-8-1×10^-5and1×10^-8-3×10^-5mol/L,respectively,the relationships between the peak currents of the second derivative waves and the concentrations are linear;the detection limits to determine the Cu^2+,Cd^2+,Ni^2+and Co^2+are8×10^-8,2×10^-7,6×10^-9and4×10^-9mol/L,respectively.Without any sample pretreatment,the method was used to directly determine the trace Cu^2+,Cd^2+,Ni^2+and Co^2+in actual zinc electrolytes with satisfactory results.The method is simple,sensitive and rapid.展开更多
AIM:The effects of cobalt,copper,cadmium and barium ions on the cysts of Entamoeba histolyt/ca (E,histolytica), an amebic dysentery agent,cultured in Robinson medium were investigated. METHODS:E.histolytica cysts and ...AIM:The effects of cobalt,copper,cadmium and barium ions on the cysts of Entamoeba histolyt/ca (E,histolytica), an amebic dysentery agent,cultured in Robinson medium were investigated. METHODS:E.histolytica cysts and trophozoites isolated from a patient with amebiasis were cultivated in the medium, incubated at 37℃ for a period of 4 days and 40×10~4/ml amebic cysts were then transferred to a fresh medium.At the second stage,0.05,0.1 and 0.2 mM of selected metal ions were added to the medium,and the effects of these ions on parasitic reproduction compared with the control group were observed. RESULTS:It was determined that the number of living parasites in all the groups containing metal ions decreased significantly starting from 30 minutes (P<0.01).CuCl_2 showed the highest lethal effect on E.histolytica cysts,whereas the lowest lethal effect was observed with CoCl_2.It was also seen that the number of living cells was decreased as the ion concentration and exposure time were increased,and that there were no living parasites in the medium at the end of 24 h (P<0.01). CONCLUSION:It may be stated that the effect of ever- increasing contamination of the environment with metal waste materials on parasites should be investigated further.展开更多
As a part of comprehensive utilization of concentrate linnaeite.this paper mainly discussed the theoretical bases and technical process conditions of separation of cobalt and nickel by two-section extraction with N,,,...As a part of comprehensive utilization of concentrate linnaeite.this paper mainly discussed the theoretical bases and technical process conditions of separation of cobalt and nickel by two-section extraction with N,,, and extraction of copper with Lix984展开更多
Several researches have been reported about the characteristic of β-Ga_2O_3 nanowires which was synthesized on nickel oxide particle.But indeed,recent researches about synthesis of β-Ga_2O_3 nanowires on oxide-assis...Several researches have been reported about the characteristic of β-Ga_2O_3 nanowires which was synthesized on nickel oxide particle.But indeed,recent researches about synthesis of β-Ga_2O_3 nanowires on oxide-assisted transition metal are limited to nickel or cobalt oxide catalyst.In this work,Gallium oxide(β-Ga_2O_3)nanowires were synthesized by a simple thermal evaporation method from gallium powder in the range of 700-1000℃ using the iron,nickel,copper,cobalt and zinc oxide as a catalyst,respectively.The β-Ga_2O_3 nanowires with single crystalline without defects were successfully synthesized at the reaction temperature of 850,900 and 950℃ in all the catalysts.But optimum experimental condition in synthesis of nanowires varied with the kind of catalyst.As increasing synthesis temperature,the morphology of gallium oxide nanowires changed from nanowires to nanorods,and its diameter increased.From these results,we could be proposed that the growth mechanism of β-Ga_2O_3 nanowires was changed with synthesis temperature of nanowires.Microstructure and morphology of Synthesized nanowire was characterized by HR-TEM,FE-SEM,EDX and XRD.展开更多
实验室比对盲样测定是检验实验室能力验证、实验室资质认定、机构考核的主要手段。土壤金属元素污染情况是第三次全国土壤普查的一个重要理化指标,为研究并解决测试实验室比对土壤盲样中铍、钒、镍、铜、锌、镉、铅的含量,采用微波消解...实验室比对盲样测定是检验实验室能力验证、实验室资质认定、机构考核的主要手段。土壤金属元素污染情况是第三次全国土壤普查的一个重要理化指标,为研究并解决测试实验室比对土壤盲样中铍、钒、镍、铜、锌、镉、铅的含量,采用微波消解-电感耦合等离子体质谱(ICP-MS)法对土壤盲样进行研究,对不同消解酸体系、检出限和定量限、测试模式和干扰消除、精密度和加标回收率、质控样品进行了探讨,并与电感耦合等离子体发射光谱(ICP-OES)法进行测试结果比对。结果表明:用6 mL HNO_(3)、2 mL HCl和1 mL HF为混合酸体系,各待测元素标准曲线相关系数大于0.999 5、检出限在0.001~3.0μg/L、定量限在0.003~9.9μg/L,采用氦气碰撞模式测试钒、镍、铜、锌、镉和铅,可以有效地降低多原子离子的干扰;采用no gas模式测试铍,可以有效地提高铍的测试灵敏度。方法精密度为0.2%~6.2%(n=6),加标回收率为92.3%~111%,采用土壤标准样品(GSS-4)进行全过程消解测试质控研究分析,各元素结果均在标准值参考范围内。用ICP-OES法测试土壤盲样中7种待测金属元素含量与用铑为内标的ICP-MS法测定值进行比对,ICP-MS法和ICP-OES法测试的各元素的相对标准偏差分别为0.60%~2.2%和0.70%~3.2%,测量结果基本一致。展开更多
文摘A new reagent 2-QADN2,7 has been synthesized and its electroana- lytical characteristics have been studied.The procedure of the adsorptive voltammetric determination of copper,nickel,cohalt and cadmium was worked out.
基金The authors are grateful to the FondoNacional de Ciencia y Tecnología(FONACIT)and Consejo de Desarrol-loCientífico,Humanístico,Tecnológico y de lasArtes(CDCHTA)for financial support,Proyects S1-97001192 and C-133105-08B respectively,Laboratorio de Análisis Químico Estructural de Materiales(LAQUEM)and La-boratorio de Cristalografía of the Universidad de Los Andes(ULA)Mérida-Venezuela.
文摘In this work, a flow injection analysis (FIA) method for the trace determination of lead, cadmium, nickel and cobalt in natural waters by formation of neutral chelates with ammonium pyrrolidine dithiocarbamate (APDC) was developed. The neutral chelates formed was retained in a mini-column packed with Linde type A zeolite (LTA) and type Y Faujasite zeolite (FAU) and then eluted with methyl isobutyl ketone (MIBK) to flame atomic absorption spectrometry (EAA) for its detection. Physicochemical characterization of this zeolite was carried out by Fourier Transform infrared spectroscopy and attenuated total reflectance (FTIR and IR-ATR), scanning electron microscopy and energy dispersive X-ray microanalysis (SEM-EDX) and X-ray power diffraction (XRD). Then, a FIA configuration was used with a column preconcentration system coupled to the detection system at room temperature (22?C). The detection limit and the relative standard deviation for 5 determinations of different solutions of Pb2+, Co2+, Ni2+ and Cd2+ for FAU and LTA zeolite were calculated. The sampling frequency ranged from 18-35 h-1 and preconcentration factors from 21-250 were achieved, for a sample volume of 6 mL using 20 mg of sorbents, indicating a high retention of the analytes on the zeolites material. The recoveries obtained in natural waters samples were close to 100% for all ions metal using synthetic zeolites, confirming the applicability of the method. The isotherm models of Langmuir, Scatchard, Freundlich and Dubinin-Radushkevich were used to study the equilibrium data, indicating that successfully followed the Freundlich and Dubinin-Radushkevich (D-R) isotherms at low metal ion concentration. The Freundlich parameter n varied between 0.35-1.01, whereas D-R isotherm yields the sorption free energy E 8 kJ.mol-1 indicating psysisorption.
文摘The simultaneous determination of cobalt, copper and nickel using 1-(2-thiazolylazo)-2-naphthol (first figure of this article) by spectrophotometric method is a difficult problem in analytical chemistry, due to spectral interferences. By multivariate calibration methods, such as partial least squares (PLS) regression, it is possible to obtain a model adjusted to the concentration values of the mixtures used in the calibration range. Orthogonal signal correction (OSC) is a preprocessing technique used for removing the information unrelated to the target variables based on constrained principal component analysis. OSC is a suitable preprocessing method for PLS calibration of mixtures without loss of prediction capacity using spectrophotometric method. In this study, the calibration model is based on absorption spectra in the 550-750-nm range for 21 different mixtures of cobalt, copper and nickel. Calibration matrices were formed from samples containing 0.05-1.05, 0.05-1.30 and 0.05-0.80 μg·mL^-1 for cobalt, copper and nickel, respectively. The root mean square error of prediction (RMSEP) for cobalt, copper and nickel with OSC and without OSC were 0.007, 0.008, 0.011 and 0.031,0.037, 0.032 μg· mL^-1, respectively. This procedure allows the simultaneous determination of cobalt, copper and nickel in synthetic and real samples and good reliability of the determination was proved.
文摘A number of synergistic solvent extraction (SSX) systems have been developed to recover nickel, cobalt, zinc and copper from sulphuric and chloride leach solutions by the solvent extraction team of CSIRO, Australia. These in- clude (1) Versatic 10/CLXS0 system for the separation of Ni from Ca in sulphate solutions, (2) Versatic 10/4PC system for the separation of Ni and Co from Mn/Mg/Ca in sulphate solutions, (3) Cyanex 471X/HRJ-4277 system for the separation of Zn from Cd in sulphate solutions, (4) Versatic 10/LIX63 system for the separation of Co from Mn/Mg/Ca in sulphate solutions, (5) Versatic 10/LIX63/TBP system for separation of Ni and Co from Mn/Mg/Ca in sulphate solutions, (6) Versatic 10/LIX63 system for the separation of cobalt from nickel in sulphate solutions by difference in kinetics, (7) Cyanex 272/LIX84 system for the separation of Cu/Fe/Zn from Ni/Co in sulphate solutions, (8) Versatic 10/LIX63fFBP system to recover Cu/Ni from strong chloride solutions, and [9) Versatic 10/LIX63 system to separate Cu from Fe in strong chloride solutions. The synergistic effect on metal separation and efficiency is presented and possible industrial applications are demonstrated. The chemical stability of selected SSX systems is also reported.
文摘Nickel, cobalt and copper were separated by solvent extraction with P204. The experimental results show that [Co(NH 3) 6] 3+ is an inert complex in extraction kinetics, therefore cobalt can be separated from nickel and copper by non equilibrium solvent extraction. Under the conditions of temperature 25?℃, contact time of two phases 10?min, phase ratio 1∶1, aqueous pH 10.10 and concentration of P204 20%, [Co(NH 3) 6] 3+ is hardly extracted by P204, while the percentage extractions of nickel and copper are 79.3% and 93.9% respectively. Nickel and copper are separated by equilibrium solvent extraction with P204. Under the conditions of temperature 25?℃, contact time of two phases 1?min, phase ratio 1∶1, equilibrium pH 4.01 and concentration of P204 20%, the separation factor of copper and nickel is 216.
文摘A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone(2-PYAINH) was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At a pH value of 7.0, 9,0, 9.0, and 8.0, respectively, which greatly increased the selectivity; nickel, copper, cobalt, and iron reacted with 2-PYAINH to form a 1:2 yellow-orange, 1:2 yellow-green, 1:2 yellow and 1:1 yellow complexes, with absorption peaks at 363, 352, 346, and 359 nm, respectively. Under the optimal conditions, Beer's law was obeyed over the ranges of 0.01-1.4, 0.01-1.5, 0.01-2.7, and 0.01-5.4 mg/L respectively. The apparent molar absorptivity and Sandell's sensitivities were 8.4×10^4, 5.2×10^4, 7.1×10^4, and 3.9×10^4 L·mol^-l·cm^-1, respectively, and 0.00069, 0.0012, 0.00078, and 0.0014 μg·cm2, respectively. The detection limits were found to be 0.001, 0.002, 0.003, and 0.01 mg/L, respectively. The detailed study of various interfering ions to make the method more sensitive was carried out and selective and several real samples were analyzed with satisfactory results.
文摘A new Schiff base (LK) obtained from 2, 4, -dihydroxybenzaldehyde and glycly-DL- phenylalanine reacted with Cu(II), Zn(II), Ni(II) and Co(II) to yield new complexes. The complexes were characterized by elemental analyses, molar conductance, 1H NMR DTA, TG, IR and UV spectroscopy. In these complexes the ligand is coordinated to the metal through its phenolic oxygen, carboxyl oxygen, imino nitrogen and amide nitrogen. All complexes are non-electrolytes and four coordinated with 1:1(metal; ligand) stoichiometry. The probable structure of the complexes is suggested
基金Project supported by the Program for New Century Excellent Talents in University (No. NCET-04-0649) and Science Foundation of China (Nos 20275020 and 20475030).
文摘Mononuclear copper(Ⅱ), nickel(Ⅱ) and cobalt(Ⅲ) tetracoordinate macrocyclic complexes were synthesized and spectroscopically characterized. The crystal structure of the three compounds were determined by X-ray crystallography. The electrochemical experimental results indicate that the three complexes could interact with DNA mainly by electrostatic interaction. The interaction of tetracoordinate macrocyclic cobalt(Ⅲ) complex with DNA was studied by cyclic voltammetry and UV-vis spectroscopy. The experimental results reveal that tetracoordinate macrocyc- lic cobalt(Ⅲ) complex could interact with DNA by electrostatic interaction to form a 1 : 1 DNA association complex with a binding constant of 7.50 ×10^3 L·mol^-1.
基金financially supported by the National Basic Research Priorities Program of China(Nos.2014CB643401 and 2013AA032003)the National Natural Science Foundation of China(No.51372019)Shanxi Collaborative Innovation Center of High Value-added Utilization of Coal-related Wastes
文摘Aim: To determine the seminal concentrations of copper, zinc, iron, cadmium, lead and nickel in bulls, rams, boars, stallions and foxes and study their correlations. Methods: Semen samples were obtained, digested and analyzed by means of the atomic absorption spectrophotometer. Data were analyzed statistically with the Student's t-test and Scheffe's test using PC programs SAS and Excel. Results: The seminal copper concentration was significantly higher in ram [(2.49±0.18) mg/kg] and fox [(2.16±0.53) mg/kg] than that in bull [(1.64±0.21) mg/kg], boar [(1.64±0.28) mg/kg] and stallion (0.86 mg/kg). In boar a significantly higher seminal zinc concentration (171.74±65.72) mg/kg] was found in comparison with stallion [(86.20±45.88) mg/kg], bull [(83.15±61.61) mg/kg], ram [( 60.46±35.37) mg/kg] and fox (13.09±5.22) mg/kg]. The iron concentration in semen was significantly higher in ram [(40.32±10.81) mg/kg), bull [(38.04±22.07) mg/kg] and fox [(33.16±24.36) mg/kg] than that in boar [(16.14±10.35) mg/kg] and stallion (12.68 mg/kg). The seminal cadmium concentration was relatively low [(0.05-0.12) mg/kg] in all studied species. The seminal lead concentration was the highest in ram [(0.35±0.68) mg/kg], which was much higher than in fox [(0.08±0.06) mg/kg], bull [(0.06±0.04) mg/kg], stallion [(0.05±0.05) mg/kg] and boar [0.02±0.03) mg/kg]. The level of seminal nickel was significantly higher in fox [(0.35±0.24) mg/kg] and ram [(0.31±0.19) mg/ kg] in comparison with bull [(0.12±0.07) mg/kg] and boar [(0.06±0.08) mg/kg]. The concentration of nickel in the semen of stallion was (0.20±0.24) mg/kg. There was a high positive correlation between seminal iron and zinc in bull (r=0.723) and stallion (r=0.723), between cadmium and lead in ram (r=0.976) and boar (r=0.973) and between iron and cadmium (r=0.783) and iron and lead (r=0.791) in boar. A high negative correlation between seminal nickel and copper in ram (r=-0.709) and between seminal copper and lead in fox (r=-0.854) was found. Conclusion: There are significant differences in the concentrations of seminal elements in different animals. There is a high concentration of seminal copper in ram and fox, a high zinc level in boar, a high iron level in bull, ram and fox and a high nickel level in ram and fox.
基金Projects (61533021,61773403) supported by the National Natural Science Foundation of China
文摘Simultaneous determination of impurity metal ions in high concentration zinc solution is very important for zinc hydrometallurgy,and the purpose is to establish a method for determining the trace Cu^2+,Cd^2+,Ni^2+and Co^2+in zinc electrolytes at the same time using the second derivative waves of single sweep oscillopolarography.Factors affecting the derivative waves of the ions were researched in a medium of dimethylglyoxime(DMG)-sodium citrate-sodium tetraborate.The results indicated that the interferences of a high concentration of Zn^2+and most other coexisting ions on the determination can be eliminated;when the Cu^2+,Cd^2+,Ni^2+and Co^2+are in the ranges of1×10^-7-3×10^-4,6×10^-7-2×10^-4,2×10^-8-1×10^-5and1×10^-8-3×10^-5mol/L,respectively,the relationships between the peak currents of the second derivative waves and the concentrations are linear;the detection limits to determine the Cu^2+,Cd^2+,Ni^2+and Co^2+are8×10^-8,2×10^-7,6×10^-9and4×10^-9mol/L,respectively.Without any sample pretreatment,the method was used to directly determine the trace Cu^2+,Cd^2+,Ni^2+and Co^2+in actual zinc electrolytes with satisfactory results.The method is simple,sensitive and rapid.
文摘AIM:The effects of cobalt,copper,cadmium and barium ions on the cysts of Entamoeba histolyt/ca (E,histolytica), an amebic dysentery agent,cultured in Robinson medium were investigated. METHODS:E.histolytica cysts and trophozoites isolated from a patient with amebiasis were cultivated in the medium, incubated at 37℃ for a period of 4 days and 40×10~4/ml amebic cysts were then transferred to a fresh medium.At the second stage,0.05,0.1 and 0.2 mM of selected metal ions were added to the medium,and the effects of these ions on parasitic reproduction compared with the control group were observed. RESULTS:It was determined that the number of living parasites in all the groups containing metal ions decreased significantly starting from 30 minutes (P<0.01).CuCl_2 showed the highest lethal effect on E.histolytica cysts,whereas the lowest lethal effect was observed with CoCl_2.It was also seen that the number of living cells was decreased as the ion concentration and exposure time were increased,and that there were no living parasites in the medium at the end of 24 h (P<0.01). CONCLUSION:It may be stated that the effect of ever- increasing contamination of the environment with metal waste materials on parasites should be investigated further.
文摘As a part of comprehensive utilization of concentrate linnaeite.this paper mainly discussed the theoretical bases and technical process conditions of separation of cobalt and nickel by two-section extraction with N,,, and extraction of copper with Lix984
文摘Several researches have been reported about the characteristic of β-Ga_2O_3 nanowires which was synthesized on nickel oxide particle.But indeed,recent researches about synthesis of β-Ga_2O_3 nanowires on oxide-assisted transition metal are limited to nickel or cobalt oxide catalyst.In this work,Gallium oxide(β-Ga_2O_3)nanowires were synthesized by a simple thermal evaporation method from gallium powder in the range of 700-1000℃ using the iron,nickel,copper,cobalt and zinc oxide as a catalyst,respectively.The β-Ga_2O_3 nanowires with single crystalline without defects were successfully synthesized at the reaction temperature of 850,900 and 950℃ in all the catalysts.But optimum experimental condition in synthesis of nanowires varied with the kind of catalyst.As increasing synthesis temperature,the morphology of gallium oxide nanowires changed from nanowires to nanorods,and its diameter increased.From these results,we could be proposed that the growth mechanism of β-Ga_2O_3 nanowires was changed with synthesis temperature of nanowires.Microstructure and morphology of Synthesized nanowire was characterized by HR-TEM,FE-SEM,EDX and XRD.
文摘实验室比对盲样测定是检验实验室能力验证、实验室资质认定、机构考核的主要手段。土壤金属元素污染情况是第三次全国土壤普查的一个重要理化指标,为研究并解决测试实验室比对土壤盲样中铍、钒、镍、铜、锌、镉、铅的含量,采用微波消解-电感耦合等离子体质谱(ICP-MS)法对土壤盲样进行研究,对不同消解酸体系、检出限和定量限、测试模式和干扰消除、精密度和加标回收率、质控样品进行了探讨,并与电感耦合等离子体发射光谱(ICP-OES)法进行测试结果比对。结果表明:用6 mL HNO_(3)、2 mL HCl和1 mL HF为混合酸体系,各待测元素标准曲线相关系数大于0.999 5、检出限在0.001~3.0μg/L、定量限在0.003~9.9μg/L,采用氦气碰撞模式测试钒、镍、铜、锌、镉和铅,可以有效地降低多原子离子的干扰;采用no gas模式测试铍,可以有效地提高铍的测试灵敏度。方法精密度为0.2%~6.2%(n=6),加标回收率为92.3%~111%,采用土壤标准样品(GSS-4)进行全过程消解测试质控研究分析,各元素结果均在标准值参考范围内。用ICP-OES法测试土壤盲样中7种待测金属元素含量与用铑为内标的ICP-MS法测定值进行比对,ICP-MS法和ICP-OES法测试的各元素的相对标准偏差分别为0.60%~2.2%和0.70%~3.2%,测量结果基本一致。