试验采用高分辨率电感耦合等离子体质谱法(High-Resolution Inductively Coupled Plasma Mass Spectrometry,HR-ICP-MS)测定钨钼矿石中钨、钼、锂、铬、钴、镍、铜、锌、镓、锗、砷、硒、铷、铌、铟、锡、锑、铼、铊和铋等元素的含量。...试验采用高分辨率电感耦合等离子体质谱法(High-Resolution Inductively Coupled Plasma Mass Spectrometry,HR-ICP-MS)测定钨钼矿石中钨、钼、锂、铬、钴、镍、铜、锌、镓、锗、砷、硒、铷、铌、铟、锡、锑、铼、铊和铋等元素的含量。参考国家一级标准物质,对HR-ICP-MS进行数据比较和精确度验证,按照相关标准规定的方法确定HR-ICP-MS的检出限。结果表明,采用HR-ICP-MS测量钨钼矿石金属元素的相对标准偏差(Relative Standard Deviation,RSD)为0.86%~9.70%,各元素的检出限介于0.002~27.000 mg/kg,加标试验后的回收率损失小于2%,该方法可靠可信,准确度和精密度都能达到测试要求。展开更多
A kind of surface modification test was introduced, by which plasma spray in argon atmosphere with CNC4500 system was applied for TA7 titanium alloy to be coated with molybdenum, and technology to produce metallurgica...A kind of surface modification test was introduced, by which plasma spray in argon atmosphere with CNC4500 system was applied for TA7 titanium alloy to be coated with molybdenum, and technology to produce metallurgical bonding at interface of coating and base meal was tested by heating in vacuum condition for diffusion after hot spray. With the help of scan electron microscope analysis （SEM）, the effect of argon inlet pressure and heating temperature on coating structure as well as product of diffusion layer were studied. The glued tensile test method was used to measure bonding strength of base metal to coating. The result has shown that both argon inlet pressure and heating temperature exert some effect on coating structure and the width of diffusion layer. A bonding strength of base metal to coating which is greater than molybdenum coating itself may be attained and can be controlled in more than 50 MPa level with tested hot spray technology.展开更多
Large quantities of spent hydrodesulfurization (HDS) catalysts are available from petrochemical industry. Disposal of spent catalyst is a problem as it falls under the category of hazardous industrial waste due to its...Large quantities of spent hydrodesulfurization (HDS) catalysts are available from petrochemical industry. Disposal of spent catalyst is a problem as it falls under the category of hazardous industrial waste due to its vanadium concentration. Most of these catalysts are usually supported on alumina containing a variable percentage of elements such as nickel or molybdenum. Hence these catalysts contain environmentally critical, and economically valuable metals such as molyb denum, vanadium, and, nickel. In this paper, a spent HDS catalyst was treated with caustic soda solution. Parameters such as temperature, time, and NaOH solution concentration have been studied thoroughly, in order to settle the appropriate conditions for the maximum recovery of molybdenum and vanadium. Under the best leaching conditions (20 %w NaOH, room temperature, 2 h) about 95% recovery of Mo and V was achieved, and the recovery of nickel obtained was of 99% in the form of NiAlO4.展开更多
Multiwalled carbon nanotubes （CNTs） were coated by a molybdenum layer using carbonyl thermal decomposition process with a precursor of molybdenum hexacarbonyl. The Mo-coated CNTs （Mo-CNTs） were added into copper p...Multiwalled carbon nanotubes （CNTs） were coated by a molybdenum layer using carbonyl thermal decomposition process with a precursor of molybdenum hexacarbonyl. The Mo-coated CNTs （Mo-CNTs） were added into copper powders to fabricate Mo-CNT/Cu composites by means of mechanical milling followed by spark plasma sintering. The Mo-CNTs were uniform dispersion in the Cu matrix when their contents were 2.5 vo1.%-7.5 vol.%, while some Mo-CNT clusters were clearly observed at additions of 10.0 vo1.%-15.0 vol.% Mo-CNTs in the mixture. The mechanical, electrical, and thermal properties of the Mo-CNT/Cu composites were characterized, and the results showed that the tensile strength and hardness were 2.0 and 2.2 times higher than those of CNT-free specimens, respectively. Moreover, the Mo-CNT/Cu composites exhibited an enhanced thermal conductivity but inferior electrical conductivity compared with sintered pure Cu. The uncoated CNT/Cu composites were fabricated by the similar processes, and the measured tensile strength, hardness, thermal conductivity, and electrical conductivity of the CNT/Cu composites were lower than those of the Mo-CNT/Cu composites.展开更多
A single solid source precursor bis-(morpholinodithioato-s,s’)-Mo was prepared and molybdenum sulphide thin film was deposited on sodalime glass using Metal Organic Chemical Vapour Deposition (MOCVD) technique at dep...A single solid source precursor bis-(morpholinodithioato-s,s’)-Mo was prepared and molybdenum sulphide thin film was deposited on sodalime glass using Metal Organic Chemical Vapour Deposition (MOCVD) technique at deposition temperature of 420?C. The film was characterized using Rutherford Backscattering Spectroscopy (RBS), Ultraviolet-Visible Spectroscopy, Four point probe technique, Scanning Electron Mi-croscopy (SEM), X-ray Diffractometry (XRD) and Atomic Force Microscopy (AFM). A direct optical band gap of 1.77 eV was obtained from the analysis of the absorption spectrum. The sheet resistance was found to be of the order of 10P–5P ΩP–1P?cmP–1P. SEM micrographs of the films showed the layered structure of the film with an estimated grain size that is less than 2 μm while XRD indicates parallel orientation of the basal plane to the substrate surface.展开更多
A new mixed-valence heterometal cluster Mo8VW2VIO26（C5H5N）8·2H2O has been synthesized under solvothermal conditions and characterized by X-ray single-crystal diffraction, IR, UV-vis and XPS spectroscopy. The ti...A new mixed-valence heterometal cluster Mo8VW2VIO26（C5H5N）8·2H2O has been synthesized under solvothermal conditions and characterized by X-ray single-crystal diffraction, IR, UV-vis and XPS spectroscopy. The title compound crystallizes in the triclinic system, space group P1 with a = 11.708（3）, b = 12.018（4）, c = 13.316（4） A, α = 112.184（4）, β = 97.844（4）, γ = 110.043（3）°, V = 1551.9（8） A3 and Z = 1 at 293（2） K. The final full-matrix least-squares refinement converged to R = 0.0414 for 4460 observed unique reflections with I 〉 2σ（I） and w R = 0.1290 for all data（5352） and S = 1.015. In addition, its thermal stability and fluorescent property have also been investigated.展开更多
文摘试验采用高分辨率电感耦合等离子体质谱法(High-Resolution Inductively Coupled Plasma Mass Spectrometry,HR-ICP-MS)测定钨钼矿石中钨、钼、锂、铬、钴、镍、铜、锌、镓、锗、砷、硒、铷、铌、铟、锡、锑、铼、铊和铋等元素的含量。参考国家一级标准物质,对HR-ICP-MS进行数据比较和精确度验证,按照相关标准规定的方法确定HR-ICP-MS的检出限。结果表明,采用HR-ICP-MS测量钨钼矿石金属元素的相对标准偏差(Relative Standard Deviation,RSD)为0.86%~9.70%,各元素的检出限介于0.002~27.000 mg/kg,加标试验后的回收率损失小于2%,该方法可靠可信,准确度和精密度都能达到测试要求。
文摘A kind of surface modification test was introduced, by which plasma spray in argon atmosphere with CNC4500 system was applied for TA7 titanium alloy to be coated with molybdenum, and technology to produce metallurgical bonding at interface of coating and base meal was tested by heating in vacuum condition for diffusion after hot spray. With the help of scan electron microscope analysis （SEM）, the effect of argon inlet pressure and heating temperature on coating structure as well as product of diffusion layer were studied. The glued tensile test method was used to measure bonding strength of base metal to coating. The result has shown that both argon inlet pressure and heating temperature exert some effect on coating structure and the width of diffusion layer. A bonding strength of base metal to coating which is greater than molybdenum coating itself may be attained and can be controlled in more than 50 MPa level with tested hot spray technology.
文摘Large quantities of spent hydrodesulfurization (HDS) catalysts are available from petrochemical industry. Disposal of spent catalyst is a problem as it falls under the category of hazardous industrial waste due to its vanadium concentration. Most of these catalysts are usually supported on alumina containing a variable percentage of elements such as nickel or molybdenum. Hence these catalysts contain environmentally critical, and economically valuable metals such as molyb denum, vanadium, and, nickel. In this paper, a spent HDS catalyst was treated with caustic soda solution. Parameters such as temperature, time, and NaOH solution concentration have been studied thoroughly, in order to settle the appropriate conditions for the maximum recovery of molybdenum and vanadium. Under the best leaching conditions (20 %w NaOH, room temperature, 2 h) about 95% recovery of Mo and V was achieved, and the recovery of nickel obtained was of 99% in the form of NiAlO4.
基金supported by the National Natural Science Foundation of China (No.50971020)the National High-Tech Research and Development Program of China (No.2009AA03Z116)
文摘Multiwalled carbon nanotubes （CNTs） were coated by a molybdenum layer using carbonyl thermal decomposition process with a precursor of molybdenum hexacarbonyl. The Mo-coated CNTs （Mo-CNTs） were added into copper powders to fabricate Mo-CNT/Cu composites by means of mechanical milling followed by spark plasma sintering. The Mo-CNTs were uniform dispersion in the Cu matrix when their contents were 2.5 vo1.%-7.5 vol.%, while some Mo-CNT clusters were clearly observed at additions of 10.0 vo1.%-15.0 vol.% Mo-CNTs in the mixture. The mechanical, electrical, and thermal properties of the Mo-CNT/Cu composites were characterized, and the results showed that the tensile strength and hardness were 2.0 and 2.2 times higher than those of CNT-free specimens, respectively. Moreover, the Mo-CNT/Cu composites exhibited an enhanced thermal conductivity but inferior electrical conductivity compared with sintered pure Cu. The uncoated CNT/Cu composites were fabricated by the similar processes, and the measured tensile strength, hardness, thermal conductivity, and electrical conductivity of the CNT/Cu composites were lower than those of the Mo-CNT/Cu composites.
文摘A single solid source precursor bis-(morpholinodithioato-s,s’)-Mo was prepared and molybdenum sulphide thin film was deposited on sodalime glass using Metal Organic Chemical Vapour Deposition (MOCVD) technique at deposition temperature of 420?C. The film was characterized using Rutherford Backscattering Spectroscopy (RBS), Ultraviolet-Visible Spectroscopy, Four point probe technique, Scanning Electron Mi-croscopy (SEM), X-ray Diffractometry (XRD) and Atomic Force Microscopy (AFM). A direct optical band gap of 1.77 eV was obtained from the analysis of the absorption spectrum. The sheet resistance was found to be of the order of 10P–5P ΩP–1P?cmP–1P. SEM micrographs of the films showed the layered structure of the film with an estimated grain size that is less than 2 μm while XRD indicates parallel orientation of the basal plane to the substrate surface.
基金supported by the National Natural Science Foundation of China(No.21003125,21073190)
文摘A new mixed-valence heterometal cluster Mo8VW2VIO26（C5H5N）8·2H2O has been synthesized under solvothermal conditions and characterized by X-ray single-crystal diffraction, IR, UV-vis and XPS spectroscopy. The title compound crystallizes in the triclinic system, space group P1 with a = 11.708（3）, b = 12.018（4）, c = 13.316（4） A, α = 112.184（4）, β = 97.844（4）, γ = 110.043（3）°, V = 1551.9（8） A3 and Z = 1 at 293（2） K. The final full-matrix least-squares refinement converged to R = 0.0414 for 4460 observed unique reflections with I 〉 2σ（I） and w R = 0.1290 for all data（5352） and S = 1.015. In addition, its thermal stability and fluorescent property have also been investigated.
