The effects of thickness and types of gold plating on the resistance to hightemperature discoloration of gold plating on cavity surface of ceramic package were investigated. Itwas found that the thicker gold plating, ...The effects of thickness and types of gold plating on the resistance to hightemperature discoloration of gold plating on cavity surface of ceramic package were investigated. Itwas found that the thicker gold plating, the less discoloration degree for ceramic packages.Non-cyanide gold plating performed better resistance to high-temperature aging than cyanide goldplating. The relationship between the gold plating thickness and the amount of diffused Ni to thegold plating of ceramic packages with Au/Ni and Au/Ni-Co platings after heating at 420℃ for 15 minwas also studied. When the gold plating thickness reach 2.0 μm and 1.6 μm for Au/Ni and Au/Ni-Coplating systems, respectively, no discoloration was observed on the gold plating surface of cavity,and the corresponding diffused Ni amounts (mass fraction) are 1.0% and 0.4%, while the diffused Coto the gold plating is 0.04%.展开更多
The effects of thickness and types of gold plating on the resistance to high temperature discoloration of gold plating on cavity surface of ceramic package were investigated. It was found that the thicker gold plating...The effects of thickness and types of gold plating on the resistance to high temperature discoloration of gold plating on cavity surface of ceramic package were investigated. It was found that the thicker gold plating, the less discoloration degree for ceramic packages. Non-cyanide gold plating performed better resistance to high-temperature aging than cyanide gold plating. The relationship between the gold plating thickness and the amount of diffused Ni to the gold plating of ceramic packages with Au/Ni and Au/Ni-Co platings after heating at 420℃for 15 min was also studied. When the gold plating thickness reach 2.0 μm and 1.6 μm for Au/Ni and Au/Ni-Co plating systems, respectively, no discoloration was observed on the gold plating surface of cavity, and the corresponding diffused Ni amounts (mass fraction) are 1.0% and 0.4%, while the diffused Co to the gold plating is 0.04%.展开更多
Garez—Litang plate junction lies in the eastern margin of the Nujiang—Lancangjiang—Jinshajiang area, NW\|trendingly and antisigmoidally extending for more than 800km from Zhidoi ,Qinghai through Garze and Litang to...Garez—Litang plate junction lies in the eastern margin of the Nujiang—Lancangjiang—Jinshajiang area, NW\|trendingly and antisigmoidally extending for more than 800km from Zhidoi ,Qinghai through Garze and Litang to Muli ,Sichuan ,with a width of 5～35km .The junction is located in the arcuate turning part of the Alpine—Himalayan—Indosinian Tethyan tectonic domain ,which lies in the structural transition position between the Yangtze plate and the Yidun area . The plate junction represents an important tectonic belt ,which is a composed of a gold mineralization belt in the east Tethyan tectonic domain.(1) Garze—Litang plate junction may be divided into the following structural units:ductile shear zone and fracture system, Paleozoic nappes ,ophiolite \|tectonic blocks,flysch formation in passive continental margin (Triassic Xikang group ),forearc sedimentary formation in active margin (Triassic Yidun group),and such boundary geological bodies as granitoids ,faulted basins and Tertiary nappes.展开更多
On the basis of the geological and geochemical studies, including chemical analysis of bulk rocks, rare-earth and trace element studies, fluid inclusion, and S and O isotopic analyses, the authors described the geolog...On the basis of the geological and geochemical studies, including chemical analysis of bulk rocks, rare-earth and trace element studies, fluid inclusion, and S and O isotopic analyses, the authors described the geological background of the deposit in detail and presented significant proofs for the conditions of formation of the Shaxi porphyry copper-gold deposit. Compared with other large and supper-large porphyry copper deposits in China and the adjacent Cu-Au mineralized areas, the ore-forming processes and conditions were analyzed; and the possibility of forming large porphyry copper deposits in the Shaxi area was discussed. The present study indicated that the ore-forming fluid and material were mainly of magmatic origin, while meteoric water played a certain role in the ore-forming processes. Interactions between subducting and overriding plates provided a major driving force for the formation of igneous rocks and the deposition of metal elements in East China since Jurassic. Based on the geo- chemical data of the Shaxi intrusive, it is found that the copper (gold) mineralization is closely related to the genesis of adakite-like intrusive in the Shaxi area. This adakite-like intrusive was formed in the subduction environment as a result of the subduction of the West Pacific plate toward the East China continent, where there is a great potentiality to form a large porphyry copper deposit.展开更多
We present the analysis of gold in plating solutions in the presence of several additive ions by portable X-ray fluorescence (XRF) revealing an optimum potassium gold cyanide concentration of 2 - 3 g/L for maximum cat...We present the analysis of gold in plating solutions in the presence of several additive ions by portable X-ray fluorescence (XRF) revealing an optimum potassium gold cyanide concentration of 2 - 3 g/L for maximum cathode efficiency. Additionally, we present the utility of XRF to determine the thickness of gold plated on copper substrates up to 6 microns.展开更多
The geotectonic setting refers to the three-dimensional space and relatedevents based on which a metallogenic system is formed and an ore-forming process takes place. Thispaper discusses the tectonic evolution of the ...The geotectonic setting refers to the three-dimensional space and relatedevents based on which a metallogenic system is formed and an ore-forming process takes place. Thispaper discusses the tectonic evolution of the southwestern margin of the North China paleocontinentand related geotectonic settings in which large or superlarge deposits are formed. Emphasis is puton the geodynamic conditions of the Jinchuan nickel-copper deposit, the Baiyin copper-polymetallicdeposit and the Hanshan gold deposit. It is significant that the three deposits occur together as a'trinity' on the same paleocontinental margin. The Jinchuan nickel-copper deposit was formed duringthe early stage of rifting of the paleocontinental margin; the Baiyin copper-polymetallic depositwas formed during the splitting stage of a continental-margin arc. The continental-margin arcspitting resulted in an 'island arc rift' in the early stage of evolution. The Hanshan gold depositwas formed within the Altun sinistral strike-slip fault system and its provenance is the'intraoceanic arc' volcanic rocks.展开更多
The West Qinling Orogen(WQO) in Central China Orogenic Belt contains numerous metasedimentary rock-hosted gold deposits(>2000 t Au), which mainly formed during two pulses: one previously recognized in the Late Tria...The West Qinling Orogen(WQO) in Central China Orogenic Belt contains numerous metasedimentary rock-hosted gold deposits(>2000 t Au), which mainly formed during two pulses: one previously recognized in the Late Triassic to Early Jurassic(T3 - J1) and one only recently identified in the Late Jurassic to Early Cretaceous(J3 - K1). Few studies have focused on the origin and geotectonic setting of the J3 - K1 gold deposits.Textural relationships, LA-ICP-MS trace element and sulfur isotope compositions of pyrites in hydrothermally altered T3 dykes within the J3 - K1 Daqiao deposit were used to constrain relative timing relationships between mineralization and pyrite growth in the dykes, and to characterize the source of ore fluid. These results are integrated with an overview of the regional geodynamic setting, to advance understanding of the tectonic driver for J3 - K1 hydrothermal gold systems. Pyrite in breccia-and dykehosted gold ores at Daqiao have similar chemical and isotopic compositions and are considered to be representative of J3 - K1 gold deposits in WQO. Co/Ni and sulfur isotope ratios suggest that ore fluids were derived from underlying Paleozoic Ni-and Se-rich carbonaceous sedimentary rocks. The geochemical data do not support the involvement of magmatic fluids. However, in the EQO(East Qinling Orogen), J3 - K1 deposits are genetically related to magmatism. Gold mineralization in WQO is contemporaneous with magmatic deposits in the EQO and both are mainly controlled by NE-and EWtrending structures produced by changes in plate motion of the Paleo-Pacific plate as it was subducted beneath the Eurasian continent. We therefore infer that the J3 - K1 structural regime facilitated the ascent of magma in the EQO and metamorphic fluids in the WQO with consequent differences in the character of contemporaneous ore deposits. If this is correct, then the far-field effects of subduction along the eastern margin of NE Asia extended 1000's of km into the continental interior.展开更多
Discusses the fuzzy control system designed using fuzzy control technology to overcome the difficulty of building an accurate mathematic model of the citric gold plating process for long time hysteresis about the conc...Discusses the fuzzy control system designed using fuzzy control technology to overcome the difficulty of building an accurate mathematic model of the citric gold plating process for long time hysteresis about the concentration of gold potassium cyanide in the process and concludes from operational results that the fuzzy control has good control over the equipment with long time hysteresis under control.展开更多
Carbon nanotubes were initially chemically modified with an H2SO4-HNO3 treatment,and subsequently activated with Pd-Sn catalytic nuclei via a one-step activation approach. Theseactivated nanotubes were used as precurs...Carbon nanotubes were initially chemically modified with an H2SO4-HNO3 treatment,and subsequently activated with Pd-Sn catalytic nuclei via a one-step activation approach. Theseactivated nanotubes were used as precursors for obtaining gold nanoparticles-attached nanotubes viasimple electroless plating. This approach provides an efficient method for attachment of metalnanostructures to carbon nanotubes. Such novel hybrid nanostructures are attractive for manyapplications.展开更多
文摘The effects of thickness and types of gold plating on the resistance to hightemperature discoloration of gold plating on cavity surface of ceramic package were investigated. Itwas found that the thicker gold plating, the less discoloration degree for ceramic packages.Non-cyanide gold plating performed better resistance to high-temperature aging than cyanide goldplating. The relationship between the gold plating thickness and the amount of diffused Ni to thegold plating of ceramic packages with Au/Ni and Au/Ni-Co platings after heating at 420℃ for 15 minwas also studied. When the gold plating thickness reach 2.0 μm and 1.6 μm for Au/Ni and Au/Ni-Coplating systems, respectively, no discoloration was observed on the gold plating surface of cavity,and the corresponding diffused Ni amounts (mass fraction) are 1.0% and 0.4%, while the diffused Coto the gold plating is 0.04%.
文摘The effects of thickness and types of gold plating on the resistance to high temperature discoloration of gold plating on cavity surface of ceramic package were investigated. It was found that the thicker gold plating, the less discoloration degree for ceramic packages. Non-cyanide gold plating performed better resistance to high-temperature aging than cyanide gold plating. The relationship between the gold plating thickness and the amount of diffused Ni to the gold plating of ceramic packages with Au/Ni and Au/Ni-Co platings after heating at 420℃for 15 min was also studied. When the gold plating thickness reach 2.0 μm and 1.6 μm for Au/Ni and Au/Ni-Co plating systems, respectively, no discoloration was observed on the gold plating surface of cavity, and the corresponding diffused Ni amounts (mass fraction) are 1.0% and 0.4%, while the diffused Co to the gold plating is 0.04%.
文摘Garez—Litang plate junction lies in the eastern margin of the Nujiang—Lancangjiang—Jinshajiang area, NW\|trendingly and antisigmoidally extending for more than 800km from Zhidoi ,Qinghai through Garze and Litang to Muli ,Sichuan ,with a width of 5～35km .The junction is located in the arcuate turning part of the Alpine—Himalayan—Indosinian Tethyan tectonic domain ,which lies in the structural transition position between the Yangtze plate and the Yidun area . The plate junction represents an important tectonic belt ,which is a composed of a gold mineralization belt in the east Tethyan tectonic domain.(1) Garze—Litang plate junction may be divided into the following structural units:ductile shear zone and fracture system, Paleozoic nappes ,ophiolite \|tectonic blocks,flysch formation in passive continental margin (Triassic Xikang group ),forearc sedimentary formation in active margin (Triassic Yidun group),and such boundary geological bodies as granitoids ,faulted basins and Tertiary nappes.
基金supported by the Knowledge Innovation Project of the Chinese Academy of Sciences (Grant No. KZCX1-YW-15)the National Natural Science Foundation of China (Grant No. 90814008)parts of experimental work is supported from the Opening Funding of State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences (GPMR0506)
文摘On the basis of the geological and geochemical studies, including chemical analysis of bulk rocks, rare-earth and trace element studies, fluid inclusion, and S and O isotopic analyses, the authors described the geological background of the deposit in detail and presented significant proofs for the conditions of formation of the Shaxi porphyry copper-gold deposit. Compared with other large and supper-large porphyry copper deposits in China and the adjacent Cu-Au mineralized areas, the ore-forming processes and conditions were analyzed; and the possibility of forming large porphyry copper deposits in the Shaxi area was discussed. The present study indicated that the ore-forming fluid and material were mainly of magmatic origin, while meteoric water played a certain role in the ore-forming processes. Interactions between subducting and overriding plates provided a major driving force for the formation of igneous rocks and the deposition of metal elements in East China since Jurassic. Based on the geo- chemical data of the Shaxi intrusive, it is found that the copper (gold) mineralization is closely related to the genesis of adakite-like intrusive in the Shaxi area. This adakite-like intrusive was formed in the subduction environment as a result of the subduction of the West Pacific plate toward the East China continent, where there is a great potentiality to form a large porphyry copper deposit.
文摘We present the analysis of gold in plating solutions in the presence of several additive ions by portable X-ray fluorescence (XRF) revealing an optimum potassium gold cyanide concentration of 2 - 3 g/L for maximum cathode efficiency. Additionally, we present the utility of XRF to determine the thickness of gold plated on copper substrates up to 6 microns.
文摘The geotectonic setting refers to the three-dimensional space and relatedevents based on which a metallogenic system is formed and an ore-forming process takes place. Thispaper discusses the tectonic evolution of the southwestern margin of the North China paleocontinentand related geotectonic settings in which large or superlarge deposits are formed. Emphasis is puton the geodynamic conditions of the Jinchuan nickel-copper deposit, the Baiyin copper-polymetallicdeposit and the Hanshan gold deposit. It is significant that the three deposits occur together as a'trinity' on the same paleocontinental margin. The Jinchuan nickel-copper deposit was formed duringthe early stage of rifting of the paleocontinental margin; the Baiyin copper-polymetallic depositwas formed during the splitting stage of a continental-margin arc. The continental-margin arcspitting resulted in an 'island arc rift' in the early stage of evolution. The Hanshan gold depositwas formed within the Altun sinistral strike-slip fault system and its provenance is the'intraoceanic arc' volcanic rocks.
基金financially supported by the National Natural Science Foundation of China (Grant No. 41325007) the GPMR State Key Laboratory (grant MSFGPMR03)+1 种基金the China Geological Survey (Grant No. 1212011120570)National Demonstration Center for Experimental Mineral Exploration Education at China University of Geosciences (Wuhan)
文摘The West Qinling Orogen(WQO) in Central China Orogenic Belt contains numerous metasedimentary rock-hosted gold deposits(>2000 t Au), which mainly formed during two pulses: one previously recognized in the Late Triassic to Early Jurassic(T3 - J1) and one only recently identified in the Late Jurassic to Early Cretaceous(J3 - K1). Few studies have focused on the origin and geotectonic setting of the J3 - K1 gold deposits.Textural relationships, LA-ICP-MS trace element and sulfur isotope compositions of pyrites in hydrothermally altered T3 dykes within the J3 - K1 Daqiao deposit were used to constrain relative timing relationships between mineralization and pyrite growth in the dykes, and to characterize the source of ore fluid. These results are integrated with an overview of the regional geodynamic setting, to advance understanding of the tectonic driver for J3 - K1 hydrothermal gold systems. Pyrite in breccia-and dykehosted gold ores at Daqiao have similar chemical and isotopic compositions and are considered to be representative of J3 - K1 gold deposits in WQO. Co/Ni and sulfur isotope ratios suggest that ore fluids were derived from underlying Paleozoic Ni-and Se-rich carbonaceous sedimentary rocks. The geochemical data do not support the involvement of magmatic fluids. However, in the EQO(East Qinling Orogen), J3 - K1 deposits are genetically related to magmatism. Gold mineralization in WQO is contemporaneous with magmatic deposits in the EQO and both are mainly controlled by NE-and EWtrending structures produced by changes in plate motion of the Paleo-Pacific plate as it was subducted beneath the Eurasian continent. We therefore infer that the J3 - K1 structural regime facilitated the ascent of magma in the EQO and metamorphic fluids in the WQO with consequent differences in the character of contemporaneous ore deposits. If this is correct, then the far-field effects of subduction along the eastern margin of NE Asia extended 1000's of km into the continental interior.
文摘Discusses the fuzzy control system designed using fuzzy control technology to overcome the difficulty of building an accurate mathematic model of the citric gold plating process for long time hysteresis about the concentration of gold potassium cyanide in the process and concludes from operational results that the fuzzy control has good control over the equipment with long time hysteresis under control.
文摘Carbon nanotubes were initially chemically modified with an H2SO4-HNO3 treatment,and subsequently activated with Pd-Sn catalytic nuclei via a one-step activation approach. Theseactivated nanotubes were used as precursors for obtaining gold nanoparticles-attached nanotubes viasimple electroless plating. This approach provides an efficient method for attachment of metalnanostructures to carbon nanotubes. Such novel hybrid nanostructures are attractive for manyapplications.
