Ni–Cr enrichment on stainless steel SS316 L resulting from chemical activation enabled the deposition of carbon by spraying a stable suspension of carbon nanoparticles; trace Ag was deposited in situ to prepare a thi...Ni–Cr enrichment on stainless steel SS316 L resulting from chemical activation enabled the deposition of carbon by spraying a stable suspension of carbon nanoparticles; trace Ag was deposited in situ to prepare a thin continuous Ag-doped carbon film on a porous carbon-coated SS316 L substrate. The corrosion resistance of this film in 0.5 mol·L^（-1） H_2SO_4 solution containing 5 ppm F- at 80°C was investigated using polarization tests. The results showed that the surface treatment of the SS316 L strongly affected the adhesion of the carbon coating to the stainless steel. Compared to the bare SS316 L, the Ag-doped carbon-coated SS316 L bipolar plate was remarkably more stable in both the anode and cathode environments of proton exchange membrane fuel cell（PEMFC） and the interface contact resistance between the specimen and Toray 060 carbon paper was reduced from 333.0 m？·cm^2 to 21.6 m？·cm^2 at a compaction pressure of 1.2 MPa.展开更多
As a solid lubricant, silver-palladium (Ag-Pd) alloy coating was investigated for the application to high temperature stud bolt. A glue layer nickel (Ni) film was deposited on the surface of the hex bolt sample and th...As a solid lubricant, silver-palladium (Ag-Pd) alloy coating was investigated for the application to high temperature stud bolt. A glue layer nickel (Ni) film was deposited on the surface of the hex bolt sample and then Ag-Pd alloy coating was performed on it using ion plating method. The friction coefficient of Ag-Pd alloy film coated bolt was lower than that of N-5000 oil coated bolt by the result of axial force measurement. The cyclic test of heat treatment was conducted to evaluate the durability of Ag-Pd alloy film coated bolt. In a cycle, sample was assembled into the block using torque wrench, followed by heating and disassembling. It was not successful to disassemble the N-5000 oil coated bolt from the block after only one cycle. However, the Ag-Pd alloy film coated bolt was able to be disassembled softly till 12 cycles.展开更多
A facile and large-scale synthesis method to fabricate silver hollow microspheres with controllable morphologies and shell thickness is described using low-cost glass microspheres as templates. The method mainly invol...A facile and large-scale synthesis method to fabricate silver hollow microspheres with controllable morphologies and shell thickness is described using low-cost glass microspheres as templates. The method mainly involves two steps of the preparation of silver-coated glass microsphere core–shell particles by a controllable liquid reduced reaction of Ag[（NH3）2]＋ solution, which only produces silver nanoparticles anchored on the surface of the thiolated glass microsphere templates, and the removal of glass microspheres by wet chemical etching with HF solution. The products are well characterized by field emitted scanning electron microscopy （SEM）, transmitted electron microscopy （TEM）, X-ray photoelectron spectra （XPS）, X-ray diffraction （XRD） and energy dispersive X-ray （EDX） etc. The as-prepared core-shell particles and hollow particles have even and compact silver shells. The electromagnetic shielding coatings based on the silver hollow microspheres are demonstrated to have high conductivity, excellent shielding effectiveness and long durability, suggesting that the silver hollow microspheres obtained here are a novel light-weight electromagnetic shielding filler and will have extensive applications in the electromagnetic compatibility fields.展开更多
W-30 wt%Cu and TiC-50 wt%Ag were successfully synthesized by a novel simplified pretreatment followed by electroless plating. The 0 wt% TiC, 0.5 wt% TiC, and 0.5 wt%TiC-0.5 wt%Ag composite powders were added to W-30 w...W-30 wt%Cu and TiC-50 wt%Ag were successfully synthesized by a novel simplified pretreatment followed by electroless plating. The 0 wt% TiC, 0.5 wt% TiC, and 0.5 wt%TiC-0.5 wt%Ag composite powders were added to W-30 wt%Cu composite powders by blending, and then reduced. The reduced W-30 Cu, W-30 Cu/0.5 TiC, and W-30 Cu-0.5 Ag/0.5 TiC composite powders were then compacted and sintered at 1 300 ℃ in protective hydrogen for 60 min. The phase and morphology of the composite powders and materials were analyzed using X-ray diffraction and field emission scanning electron microscopy. The relative density, electrical conductivity, and hardness of the sintered samples were examined. Results showed that W-30 Cu and TiC-Ag composite powders with uniform structure were obtained using simplified pretreatment followed by electroless plating. The addition of TiC particles can significantly increase the compressive strength and hardness of the W-30 Cu composite material but decrease the electrical conductivity. Next, 0.5 wt% Ag was added to prepare W-30 Cu-0.5 Ag/TiC composites with excellent electrical conductivity. The electrical conductivity of these composites(61.2%) is higher than that in the national standard(the imaginary line denotes electrical conductivity of GB IACS 42%) of 45.7%.展开更多
A simple electroless plating process was employed to prepare silver-coated glass frits for solar cells. The surface of the glass frits was modified with polyvinyl-pyrrolidone（PVP） before the electroless plating proc...A simple electroless plating process was employed to prepare silver-coated glass frits for solar cells. The surface of the glass frits was modified with polyvinyl-pyrrolidone（PVP） before the electroless plating process. Infrared（IR） spectroscopy,field emission scanning electron microscopy（FESEM）, and x-ray diffraction（XRD） were used to characterize the PVP modified glass frits and investigate the mechanism of the modification process. It was found that the PVP molecules adsorbed on the glass frit surface and reduced the silver ions to the silver nanoparticles. Through epitaxial growth, these nanoparticles were uniformly deposited onto the surface of the glass frit. Silicon solar cells with this novel silver coating exhibited a photoelectric conversion efficiency increase of 0.33%. Compared with the electroless plating processes, this method provides a simple route to prepare silver-coated glass frits without introducing impurity ions.展开更多
The Suichang mine is the largest silicified vein-type silver-gold mineralization system in Southeast China, whose ore bodies are controlled by shear zones developing in Lower Proterozoic gneiss terrene with initial mi...The Suichang mine is the largest silicified vein-type silver-gold mineralization system in Southeast China, whose ore bodies are controlled by shear zones developing in Lower Proterozoic gneiss terrene with initial migmatization, which is covered by Upper Jurassic and Lower Cretaceous volcanic rock system and cut by acidic igneous veins of Jurassic and Cretaceous. The conclusions are as follows: (1) The ore-forming fluid is defined as superhigh tectonic-metamorphic fluid on the base of : 1 (D)-(18O) values 2 fluid inclusions;3 trace elements of pyrite from ores. (2) The shear zone silicified orebod-ies occurred in proterozoic, Jurassic and Cretaceous, which have been transforms in part by ore-bearing comb quartz vein of volcanism.展开更多
基金financially supported by the National Natural Science Foundation of China(No.21106012)the Educational Department Foundation of Liaoning Province of China(NO.L2014180)
文摘Ni–Cr enrichment on stainless steel SS316 L resulting from chemical activation enabled the deposition of carbon by spraying a stable suspension of carbon nanoparticles; trace Ag was deposited in situ to prepare a thin continuous Ag-doped carbon film on a porous carbon-coated SS316 L substrate. The corrosion resistance of this film in 0.5 mol·L^（-1） H_2SO_4 solution containing 5 ppm F- at 80°C was investigated using polarization tests. The results showed that the surface treatment of the SS316 L strongly affected the adhesion of the carbon coating to the stainless steel. Compared to the bare SS316 L, the Ag-doped carbon-coated SS316 L bipolar plate was remarkably more stable in both the anode and cathode environments of proton exchange membrane fuel cell（PEMFC） and the interface contact resistance between the specimen and Toray 060 carbon paper was reduced from 333.0 m？·cm^2 to 21.6 m？·cm^2 at a compaction pressure of 1.2 MPa.
基金the research fund of the Korea Institute of Materials Science, a subsidiary branch of the Korea Institute of Machinery and Materialssupported by a grant from the Fundamental R&D Program for Core Technology of Materials funded by the Ministry of Knowledge Economy, Republic of Korea
文摘As a solid lubricant, silver-palladium (Ag-Pd) alloy coating was investigated for the application to high temperature stud bolt. A glue layer nickel (Ni) film was deposited on the surface of the hex bolt sample and then Ag-Pd alloy coating was performed on it using ion plating method. The friction coefficient of Ag-Pd alloy film coated bolt was lower than that of N-5000 oil coated bolt by the result of axial force measurement. The cyclic test of heat treatment was conducted to evaluate the durability of Ag-Pd alloy film coated bolt. In a cycle, sample was assembled into the block using torque wrench, followed by heating and disassembling. It was not successful to disassemble the N-5000 oil coated bolt from the block after only one cycle. However, the Ag-Pd alloy film coated bolt was able to be disassembled softly till 12 cycles.
基金Supported by the National High Technology Research and Development Program of China (No. 2006AA03Z461)the National Defense Fundamental Scientific Research Program (No. A1420080185)
文摘A facile and large-scale synthesis method to fabricate silver hollow microspheres with controllable morphologies and shell thickness is described using low-cost glass microspheres as templates. The method mainly involves two steps of the preparation of silver-coated glass microsphere core–shell particles by a controllable liquid reduced reaction of Ag[（NH3）2]＋ solution, which only produces silver nanoparticles anchored on the surface of the thiolated glass microsphere templates, and the removal of glass microspheres by wet chemical etching with HF solution. The products are well characterized by field emitted scanning electron microscopy （SEM）, transmitted electron microscopy （TEM）, X-ray photoelectron spectra （XPS）, X-ray diffraction （XRD） and energy dispersive X-ray （EDX） etc. The as-prepared core-shell particles and hollow particles have even and compact silver shells. The electromagnetic shielding coatings based on the silver hollow microspheres are demonstrated to have high conductivity, excellent shielding effectiveness and long durability, suggesting that the silver hollow microspheres obtained here are a novel light-weight electromagnetic shielding filler and will have extensive applications in the electromagnetic compatibility fields.
基金Funded by the National Magnetic Confinement Fusion Program(No.2014GB121001)
文摘W-30 wt%Cu and TiC-50 wt%Ag were successfully synthesized by a novel simplified pretreatment followed by electroless plating. The 0 wt% TiC, 0.5 wt% TiC, and 0.5 wt%TiC-0.5 wt%Ag composite powders were added to W-30 wt%Cu composite powders by blending, and then reduced. The reduced W-30 Cu, W-30 Cu/0.5 TiC, and W-30 Cu-0.5 Ag/0.5 TiC composite powders were then compacted and sintered at 1 300 ℃ in protective hydrogen for 60 min. The phase and morphology of the composite powders and materials were analyzed using X-ray diffraction and field emission scanning electron microscopy. The relative density, electrical conductivity, and hardness of the sintered samples were examined. Results showed that W-30 Cu and TiC-Ag composite powders with uniform structure were obtained using simplified pretreatment followed by electroless plating. The addition of TiC particles can significantly increase the compressive strength and hardness of the W-30 Cu composite material but decrease the electrical conductivity. Next, 0.5 wt% Ag was added to prepare W-30 Cu-0.5 Ag/TiC composites with excellent electrical conductivity. The electrical conductivity of these composites(61.2%) is higher than that in the national standard(the imaginary line denotes electrical conductivity of GB IACS 42%) of 45.7%.
文摘A simple electroless plating process was employed to prepare silver-coated glass frits for solar cells. The surface of the glass frits was modified with polyvinyl-pyrrolidone（PVP） before the electroless plating process. Infrared（IR） spectroscopy,field emission scanning electron microscopy（FESEM）, and x-ray diffraction（XRD） were used to characterize the PVP modified glass frits and investigate the mechanism of the modification process. It was found that the PVP molecules adsorbed on the glass frit surface and reduced the silver ions to the silver nanoparticles. Through epitaxial growth, these nanoparticles were uniformly deposited onto the surface of the glass frit. Silicon solar cells with this novel silver coating exhibited a photoelectric conversion efficiency increase of 0.33%. Compared with the electroless plating processes, this method provides a simple route to prepare silver-coated glass frits without introducing impurity ions.
基金Chinese Gold Management. Office (No.93-45-33) and Zhejiag Metallurgical (No. 98-27).
文摘The Suichang mine is the largest silicified vein-type silver-gold mineralization system in Southeast China, whose ore bodies are controlled by shear zones developing in Lower Proterozoic gneiss terrene with initial migmatization, which is covered by Upper Jurassic and Lower Cretaceous volcanic rock system and cut by acidic igneous veins of Jurassic and Cretaceous. The conclusions are as follows: (1) The ore-forming fluid is defined as superhigh tectonic-metamorphic fluid on the base of : 1 (D)-(18O) values 2 fluid inclusions;3 trace elements of pyrite from ores. (2) The shear zone silicified orebod-ies occurred in proterozoic, Jurassic and Cretaceous, which have been transforms in part by ore-bearing comb quartz vein of volcanism.
