A method was developed for the simultaneous determination of seven trace impurities (Cd, Mn, Pb, Zn, Cu, Fe and Ni) in high purity cobalt oxide by ICP AES. The matrix effect was eliminated by preci pitation with 1 nit...A method was developed for the simultaneous determination of seven trace impurities (Cd, Mn, Pb, Zn, Cu, Fe and Ni) in high purity cobalt oxide by ICP AES. The matrix effect was eliminated by preci pitation with 1 nitroso 2 naphthol. The matrix effect of cobalt on the absorptions of trace impurities, the effects of reaction time, pH value, dosage of precipitant on the formation of cobalt 1 nitroso 2 naphthol complex, the effects of hydrochloric acid on the stability of this complex and masking of elements were studied. Recoveries of the impurities in spiked sample are from 90% to 110% with a precision of 1.1% 5.0% RSD. The detection limits of the seven elements are in the range of 0.01 0.24μg/g. The method can be applied to the analysis of high purity cobalt metal, cobalt oxide and other cobalt compounds.展开更多
The contents ofMg, Al, Si, Ti, Cr, Mn, Fe, Co, Cu, Ga, As, Se, Cd, Sb, Pb and Bi in high purity nickel were determined by high resolution inductively coupled plasma mass spectrometry （HR-ICP-MS）. The sample was diss...The contents ofMg, Al, Si, Ti, Cr, Mn, Fe, Co, Cu, Ga, As, Se, Cd, Sb, Pb and Bi in high purity nickel were determined by high resolution inductively coupled plasma mass spectrometry （HR-ICP-MS）. The sample was dissolved in HNO3 and HCI by microwave digestion. Most of the spectral interferences could be avoided by measuring in the high resolution mode. The matrix effects because of the presence of excess HC1 and nickel were evaluated. Correction for matrix effects was made using Sc, Rh and T1 as internal standards. The optimum conditions for the determination were tested and discussed. The detection limits range from 0.012 to 1.76 ~tg/g depending on the type of elements. The applicability of the proposed method is also validated by the analysis of high purity nickel reference material （NIST SRM 671）. The relative standard deviation （RSD） is less than 3.3%. Results for determination of trace elements in high purity nickel were presented.展开更多
A series of sweeping detonation experiments were conducted to study the grain boundary effects during the primary spallation of high-purity copper cylinder.The free surface velocity profile of the shocked samples was ...A series of sweeping detonation experiments were conducted to study the grain boundary effects during the primary spallation of high-purity copper cylinder.The free surface velocity profile of the shocked samples was measured by Doppler pins systems.The soft-recovered samples were characterized by optical and electron backscatter diffraction microscopy,and the effects of microstructures like grain boundaries,and crystal orientation on spall behavior were investigated.The results indicated that the critical stress of deformation twinning in cylindrical copper increased.The nucleation sites of spallation damage were determined by the joint influence of the grain orientation(Taylor factor)and the angle between grain boundaries and radial impact-stress direction.Voids were prone to nucleating at the grain boundaries perpendicular to the radial impact-stress direction.Nevertheless,the number of voids nucleated at boundaries was relatively different from the results obtained from the plate impact experiment and plate sweeping detonation experiment,which is a result of the curvature that existed in the cylindrical copper and the obliquity of the impact-stress direction during sweeping detonation loading.展开更多
Preparation of high purity ruthenium nitrosyl nitrate using spent Ru-Zn/ZrO_(2)catalyst was studied,including melting and leaching to obtain potassium ruthenate solution,reduction,dissolving,concentrating and drying t...Preparation of high purity ruthenium nitrosyl nitrate using spent Ru-Zn/ZrO_(2)catalyst was studied,including melting and leaching to obtain potassium ruthenate solution,reduction,dissolving,concentrating and drying to obtain ruthenium trichloride,nitrosation and hydrolysis to obtain ruthenium nitrosyl hydroxide,removing of K^(+)and Cl^(-),and neutralization with nitric acid.The effects of temperature,concentration,time and pH on the yield and purity of intermediates and final product were studied,and the optimum process conditions were obtained.The yield of ruthenium nitrosyl nitrate is 92%,the content of ruthenium in high purity product is 32.16%,and the content of Cl^(-)and K^(+)are much less than 0.005%.The reaction kinetics of ruthenium nitrosyl chloride to ruthenium nitrosyl hydroxide was studied.The reaction orders of Ru(NO)Cl_(3)at 40,55 and 70℃are 0.39,0.37 and 0.39,respectively,while those of KOH are 0.16,0.15 and 0.17,respectively.The activation energy is-2.33 k J/mol.展开更多
Cotton is said to be the backbone of Pakistan's economy.Cotton production is facing many challenges such as climate change,pests and diseases,and competition from food crops(Ali et al.,2019).One of the major issue...Cotton is said to be the backbone of Pakistan's economy.Cotton production is facing many challenges such as climate change,pests and diseases,and competition from food crops(Ali et al.,2019).One of the major issues faced by cotton production is seed purity,as cotton is often cross-pollinated,therefore breeders are hard to maintain seed purity.For example,non-Bt cotton varieties are often contaminated with Bt seeds which is an important limiting factor.Another important consideration in cotton breeding is rapid generation advancement.展开更多
Determination of thirty four trace metal elements in electronic high purity hydrochloric acid by ICP-MS (Standard Condition, Plasma Screen Condition) with membrane desolvation was described. Matrix effects were compen...Determination of thirty four trace metal elements in electronic high purity hydrochloric acid by ICP-MS (Standard Condition, Plasma Screen Condition) with membrane desolvation was described. Matrix effects were compensated by adding rhodium as the internal standard. Detection limits is 0.1 to 100 ng/L; the recovery of the method is 90%-110%. Long term RSD was less than 5%. The results from ICP and ICP-MS are correspondent. ICP-MS improves the accuracy and efficiency of analyses.展开更多
10001 A Precise Coulometric Titration Method forthe Determination of Purity of Sodium Carbonate.Tang Gaohua,Lin Dawei: 1(2). 1980. pp.142--146.This paper describes the method artd device of precisecoulometric titratio...10001 A Precise Coulometric Titration Method forthe Determination of Purity of Sodium Carbonate.Tang Gaohua,Lin Dawei: 1(2). 1980. pp.142--146.This paper describes the method artd device of precisecoulometric titration at constant current for thedetermination of purity of sodium carbonate. The con-ditions of measurement are stated in detail. By thismethod. the attainable precision is 0.004%. and thetotal uncertainty is 0.005%.展开更多
文摘A method was developed for the simultaneous determination of seven trace impurities (Cd, Mn, Pb, Zn, Cu, Fe and Ni) in high purity cobalt oxide by ICP AES. The matrix effect was eliminated by preci pitation with 1 nitroso 2 naphthol. The matrix effect of cobalt on the absorptions of trace impurities, the effects of reaction time, pH value, dosage of precipitant on the formation of cobalt 1 nitroso 2 naphthol complex, the effects of hydrochloric acid on the stability of this complex and masking of elements were studied. Recoveries of the impurities in spiked sample are from 90% to 110% with a precision of 1.1% 5.0% RSD. The detection limits of the seven elements are in the range of 0.01 0.24μg/g. The method can be applied to the analysis of high purity cobalt metal, cobalt oxide and other cobalt compounds.
基金Project(21075138) supported by the National Natural Science Foundation of ChinaProject(cstc2011jjA0780) supported by Natural Science Foundation of Chongqing City,ChinaProject(KJ121311) supported by Educational Commission of Chongqing City of China
文摘The contents ofMg, Al, Si, Ti, Cr, Mn, Fe, Co, Cu, Ga, As, Se, Cd, Sb, Pb and Bi in high purity nickel were determined by high resolution inductively coupled plasma mass spectrometry （HR-ICP-MS）. The sample was dissolved in HNO3 and HCI by microwave digestion. Most of the spectral interferences could be avoided by measuring in the high resolution mode. The matrix effects because of the presence of excess HC1 and nickel were evaluated. Correction for matrix effects was made using Sc, Rh and T1 as internal standards. The optimum conditions for the determination were tested and discussed. The detection limits range from 0.012 to 1.76 ~tg/g depending on the type of elements. The applicability of the proposed method is also validated by the analysis of high purity nickel reference material （NIST SRM 671）. The relative standard deviation （RSD） is less than 3.3%. Results for determination of trace elements in high purity nickel were presented.
基金Projects(51871243,51574290)supported by the National Natural Science Foundation of ChinaProject(2019JJ40381)supported by the Natural Science Foundation of Hunan Province,ChinaProject supported by the Guangdong-Hong Kong-Macao Joint Laboratory for Neutron Scattering Science and Technology,China。
文摘A series of sweeping detonation experiments were conducted to study the grain boundary effects during the primary spallation of high-purity copper cylinder.The free surface velocity profile of the shocked samples was measured by Doppler pins systems.The soft-recovered samples were characterized by optical and electron backscatter diffraction microscopy,and the effects of microstructures like grain boundaries,and crystal orientation on spall behavior were investigated.The results indicated that the critical stress of deformation twinning in cylindrical copper increased.The nucleation sites of spallation damage were determined by the joint influence of the grain orientation(Taylor factor)and the angle between grain boundaries and radial impact-stress direction.Voids were prone to nucleating at the grain boundaries perpendicular to the radial impact-stress direction.Nevertheless,the number of voids nucleated at boundaries was relatively different from the results obtained from the plate impact experiment and plate sweeping detonation experiment,which is a result of the curvature that existed in the cylindrical copper and the obliquity of the impact-stress direction during sweeping detonation loading.
基金Project(22178392)supported by the National Natural Science Foundation of China。
文摘Preparation of high purity ruthenium nitrosyl nitrate using spent Ru-Zn/ZrO_(2)catalyst was studied,including melting and leaching to obtain potassium ruthenate solution,reduction,dissolving,concentrating and drying to obtain ruthenium trichloride,nitrosation and hydrolysis to obtain ruthenium nitrosyl hydroxide,removing of K^(+)and Cl^(-),and neutralization with nitric acid.The effects of temperature,concentration,time and pH on the yield and purity of intermediates and final product were studied,and the optimum process conditions were obtained.The yield of ruthenium nitrosyl nitrate is 92%,the content of ruthenium in high purity product is 32.16%,and the content of Cl^(-)and K^(+)are much less than 0.005%.The reaction kinetics of ruthenium nitrosyl chloride to ruthenium nitrosyl hydroxide was studied.The reaction orders of Ru(NO)Cl_(3)at 40,55 and 70℃are 0.39,0.37 and 0.39,respectively,while those of KOH are 0.16,0.15 and 0.17,respectively.The activation energy is-2.33 k J/mol.
基金the Research Project at International Center for Chemical and Biological Sciences,University of Karachi,Karachi,Pakistan。
文摘Cotton is said to be the backbone of Pakistan's economy.Cotton production is facing many challenges such as climate change,pests and diseases,and competition from food crops(Ali et al.,2019).One of the major issues faced by cotton production is seed purity,as cotton is often cross-pollinated,therefore breeders are hard to maintain seed purity.For example,non-Bt cotton varieties are often contaminated with Bt seeds which is an important limiting factor.Another important consideration in cotton breeding is rapid generation advancement.
文摘Determination of thirty four trace metal elements in electronic high purity hydrochloric acid by ICP-MS (Standard Condition, Plasma Screen Condition) with membrane desolvation was described. Matrix effects were compensated by adding rhodium as the internal standard. Detection limits is 0.1 to 100 ng/L; the recovery of the method is 90%-110%. Long term RSD was less than 5%. The results from ICP and ICP-MS are correspondent. ICP-MS improves the accuracy and efficiency of analyses.
文摘10001 A Precise Coulometric Titration Method forthe Determination of Purity of Sodium Carbonate.Tang Gaohua,Lin Dawei: 1(2). 1980. pp.142--146.This paper describes the method artd device of precisecoulometric titration at constant current for thedetermination of purity of sodium carbonate. The con-ditions of measurement are stated in detail. By thismethod. the attainable precision is 0.004%. and thetotal uncertainty is 0.005%.
