Non-ferrous metal smelting poses significant risks to public health.Specifically,the copper smelting process releases arsenic,a semi-volatile metalloid,which poses an emerging exposure risk to both workers and nearby ...Non-ferrous metal smelting poses significant risks to public health.Specifically,the copper smelting process releases arsenic,a semi-volatile metalloid,which poses an emerging exposure risk to both workers and nearby residents.To comprehensively understand the internal exposure risks of metal(loid)s from copper smelting,we explored eighteen metal(loid)s and arsenic metabolites in the urine of both occupational and non-occupational populations using inductively coupled plasma mass spectrometry with high-performance liquid chromatography and compared their health risks.Results showed that zinc and copper(485.38 and 14.00μg/L),and arsenic,lead,cadmium,vanadium,tin and antimony(46.80,6.82,2.17,0.40,0.44 and 0.23μg/L,respectively)in workers(n=179)were significantly higher compared to controls(n=168),while Zinc,tin and antimony(412.10,0.51 and 0.15μg/L,respectively)of residents were significantly higher than controls.Additionally,workers had a higher monomethyl arsenic percentage(MMA%),showing lower arsenic methylation capacity.Source appointment analysis identified arsenic,lead,cadmium,antimony,tin and thallium as co-exposure metal(loid)s from copper smelting,positively relating to the age of workers.The hazard index(HI)of workers exceeded 1.0,while residents and control were approximately at 1.0.Besides,all three populations had accumulated cancer risks exceeding 1.0×10^(-4),and arsenite(AsIII)was the main contributor to the variation of workers and residents.Furthermore,residents living closer to the smelting plant had higher health risks.This study reveals arsenic exposure metabolites and multiple metals as emerging contaminants for copper smelting exposure populations,providing valuable insights for pollution control in non-ferrous metal smelting.展开更多
To acquire non-ferrous metals related news from different countries’internet,we proposed a cross-lingual non-ferrous metals related news recognition method based on CNN with a limited bilingual dictionary.Firstly,con...To acquire non-ferrous metals related news from different countries’internet,we proposed a cross-lingual non-ferrous metals related news recognition method based on CNN with a limited bilingual dictionary.Firstly,considering the lack of related language resources of non-ferrous metals,we use a limited bilingual dictionary and CCA to learn cross-lingual word vector and to represent news in different languages uniformly.Then,to improve the effect of recognition,we use a variant of the CNN to learn recognition features and construct the recognition model.The experimental results show that our proposed method acquires better results.展开更多
The low melting point metallic tin powder or alloy of tin and lead was blended with polypropylene. A kind of in situ composite has been prepared. The variations of torque were studied when the composites were mixed in...The low melting point metallic tin powder or alloy of tin and lead was blended with polypropylene. A kind of in situ composite has been prepared. The variations of torque were studied when the composites were mixed in Haake torque rheogeniometer. By way of capillary extrusion, effects upon rheology of the in situ composites of the low melting point metals (LMPM) and coupling agent for their different variety and content, were investigated. From flow curves, the results indicate that in situ composites mixed with the LMPM are a kind of pseudoplastic fluid. If the LMPM were melted, the higher the content of the LMPM, the lower apparent viscosity of composites. Meanwhile, when the coupling agent is added into composites , the viscosity of composite will go up first and drop then. This shows that the LMPM have a promoter flow action on the polypropylene.展开更多
The Rare Earths Research Institute(the former Rare Earths Research Laboratory)under the GRINM,the first institute to conduct R&D for rare earths(RE)industry in China,was founded in 1958.The Institutewas mainly eng...The Rare Earths Research Institute(the former Rare Earths Research Laboratory)under the GRINM,the first institute to conduct R&D for rare earths(RE)industry in China,was founded in 1958.The Institutewas mainly engaged in the research work of comprehensive utilization of the mine at Baiyun-ebo,the largest展开更多
The Rare Earths Research Institute(the former Rare Earths Research Laboratory)under the GRINM,the first institute to conduct R&D for rare earths(RE)industry in China,was founded in 1958.The Institutewas mainly eng...The Rare Earths Research Institute(the former Rare Earths Research Laboratory)under the GRINM,the first institute to conduct R&D for rare earths(RE)industry in China,was founded in 1958.The Institutewas mainly engaged in the research work of comprehensive utilization of the mine at Baiyun-ebo,the largestRE mine in the world,and the ion adsorption type RE mineral in southern China.The ore decomposition,展开更多
The waste products, such as induction furnace slag, ladle furnace slag, air pollution control dust, and ramming mass collected from major iron processing industries in Chittagong, Bangladesh were analyzed for heavy me...The waste products, such as induction furnace slag, ladle furnace slag, air pollution control dust, and ramming mass collected from major iron processing industries in Chittagong, Bangladesh were analyzed for heavy metals and naturally radioactive elements. The concentrations of heavy metals Fe, Cr, Mn, Co, Cd, Ni, Pb, Cu and Zn were obtained from atomic absorption spectrophotometer (AAS) analysis with flame atomizer and the radioactivities due to 226Ra, 232Th and 40K were determined using high purity germanium (HPGe) detector of well shielded gamma-ray counting system. From the mean specific activities of the above three natural radionuclides in the investigated samples, the radium equivalent activity (Raeq) and the external hazard index (Hex) were calculated. The study showed the prospect of contamination of environmental materials (viz., soil, water, air, plant) due to many of these investigated elements by using the collected waste products in landfill. The chemical process of ion exchange indicates that the elevated heavy metals in soil can play a role to increase the natural radioactivity of the soil. The obtained Raeq as well as Hex indicated the insignificant radiation hazard due to the activities of primordial radionuclides found in the investigated samples.展开更多
China’s non-ferrous metals industry has constantly maintained a steady, rapid and healthy development since the reform and opening to the outside world. By the end of 1994, the annual output often kinds of common non...China’s non-ferrous metals industry has constantly maintained a steady, rapid and healthy development since the reform and opening to the outside world. By the end of 1994, the annual output often kinds of common non-ferrous metals such as copper, aluminium, lead, and zinc had reached 3.701 million tons, a 12.2 percent increase over the previous year; the qualification rate of principal products and the output value rate of good quality products all achieved an increase over the previous year. China has展开更多
Since the beginning of the 1990s, the China non-ferrous metals export trade has steadily increased, foreign economic and technical cooperation has further expanded and foreign capital utilization and overseas developm...Since the beginning of the 1990s, the China non-ferrous metals export trade has steadily increased, foreign economic and technical cooperation has further expanded and foreign capital utilization and overseas development have achieved new breakthroughs.展开更多
Vice president of China National Nonferrous Metals Industries Corporation Mr. WoTingshu said:"The output of 10 kinds of nonferrous metals amounted to 2.45 Mt." This factmean1s that the national plan for nonf...Vice president of China National Nonferrous Metals Industries Corporation Mr. WoTingshu said:"The output of 10 kinds of nonferrous metals amounted to 2.45 Mt." This factmean1s that the national plan for nonferrous metals production fulfiled earlier. The 10 kinds ofnonferrous metals are aluminium, magnesium, lead, zinc, copper, tin, nickel, antimony mercuryand titanium.展开更多
The China Non-ferrous MetalsIndustry Corporation has putforward ten development policiesfor the Ninth Five-year Plan period,according to the central government’sinstruction to change the way of economicgrowth,and rai...The China Non-ferrous MetalsIndustry Corporation has putforward ten development policiesfor the Ninth Five-year Plan period,according to the central government’sinstruction to change the way of economicgrowth,and raise the integral quality andbenefit of the national economy:展开更多
Since the the launch of theeconomic reform and openingdrive,especially the foundingof the China Non-ferrous MetalsIndustry Corporation,China’s non-ferrous metals industry hassustained rapid and healthy growth.
Several pillar industries in the national economy, including non-ferrous metal metallurgy industry. However, with the rapid growth of the metallurgical industry, the recycling technology has not been reformed in time,...Several pillar industries in the national economy, including non-ferrous metal metallurgy industry. However, with the rapid growth of the metallurgical industry, the recycling technology has not been reformed in time, resulting in frequent environmental pollution. For example, metal waste residue or waste liquid cannot be completely recycled and treated. Therefore, "environmental protection" and "green" have become particularly important issues, and environmental issues also determine the future survival and development of mankind. In this paper, the author mainly studies the non-ferrous metal metallurgy and the urgent need through the environmental protection method, and on this basis, explores the green environmental protection metallurgy method, and gives the related suggestion.展开更多
A route combining powder metallurgy and subsequent friction stir processing was utilized to fabricate carbon nanotube （CNT） reinforced AI （CNT/AI） and 6061AI （CNT/6061AI） composites. Microstructural observations...A route combining powder metallurgy and subsequent friction stir processing was utilized to fabricate carbon nanotube （CNT） reinforced AI （CNT/AI） and 6061AI （CNT/6061AI） composites. Microstructural observations indicated that CNTs were uniformly dispersed in the matrix in both CNT/AI and CNT/6061AI composites. Mg and Si elements tended to segregate at CNT-AI interfaces in the CNT/6061AI composite during artificial aging treatment. The tensile properties of both the AI and 6061AI were increased by CNT incorporation. The electrical conductivity of CNT/AI was decreased by CNT addition, while CNT/6061AI exhibited an increase in electrical conductivity due to the Mg and Si segregation.展开更多
Hierarchical Ag-SiO_2@Fe_3O_4 magnetic composites were selected for elemental mercury(Hg^0) removal from non-ferrous metal smelting flue gas in this study. Results showed that the hierarchical Ag-SiO_2@Fe_3O_4 magneti...Hierarchical Ag-SiO_2@Fe_3O_4 magnetic composites were selected for elemental mercury(Hg^0) removal from non-ferrous metal smelting flue gas in this study. Results showed that the hierarchical Ag-SiO_2@Fe_3O_4 magnetic composites had favorable Hg^0 removal ability at low temperature. Moreover, the adsorption capacity of hierarchical magnetic composite is much larger than that of pure Fe_3O_4 and SiO_2@Fe_3O_4. The Hg^0 removal efficiency reached the highest value as approximately 92% under the reaction temperature of 150°C, while the removal efficiency sharply reduced in the absence of O_2. The characterization results indicated that Ag nanoparticles grew on the surface of SiO_2@Fe_3O_4 support. The large surface area of SiO_2 supplied efficient reaction room for Hg and Ag atoms. Ag–Hg amalgam is generated on the surface of the composites. In addition, this magnetic material could be easily separated from fly ashes when adopted for treating real flue gas, and the spent materials could be regenerated using a simple thermal-desorption method.展开更多
The Nanling region is an important nonferrous and rare metal metallogenic province in South China, in which most of the deposits are related to granitoids in genesis. It covers southern Hunan, southern Jiangxi, Guangx...The Nanling region is an important nonferrous and rare metal metallogenic province in South China, in which most of the deposits are related to granitoids in genesis. It covers southern Hunan, southern Jiangxi, Guangxi, Guangdong and Fujian provinces, with a total area of about 550,000 km2. This metallogenic province is well known in the world for its rich tungsten and tin resources. In the past 40-odd years, a vast amount of mineral exploration activities and studies of the geology of mineral deposits have been carried out and great achievements obtained in the province. This paper is focused on a discussion about the deep tectonic processes in the orogenic belt during the Mesozoic and their contribution to the superaccumulation of metals. Tectonically, this metallogenic province is composed of three units: (1) the marginal continental orogenic belt in the Southeastern Coast fold system in the Yanshanian; (2) the intercontinental orogenic belt in the collision suture belt between the Yangtze and Cathay-sian plates mainly in the Caledonian; and (3) the intracontinental orogenic belt induced by subduction of the ocean crust and delimination of the mantle lithosphere in the Yanshanian. It is suggested that superaccumulation of metals in this metallogenic province was caused by the existence of mantle rooted tectonics at the depth based on comprehensive studies of geophysical information of seismic, geothermal and magnetotelluric surveys in Nanling and its adjacent areas. The Xihuashan wolframite quartz vein deposit, the Shizhuyuan W, Sn, Mo, Bi greisen-skarn deposit and the Dachang tin-polymetallic deposit are three typical examples of the deep tectonic processes. However, this kind of deep tectonic processes only act as the 'engine' of the superaccumulation of metals, which means that they should have to correspond with the super-crust ore-controlling pattern of 'lines-rows-clusters' (L-R-C). This recog-nization is expected to play an important role in assessment of mineral resources in this province.展开更多
In this study, friction stir processing（FSP） was employed to modify cold-sprayed（CSed） AA2024/Al2 O3 metal matrix composites（MMCs）. Three different rotation speeds with a constant traverse speed were used for FS...In this study, friction stir processing（FSP） was employed to modify cold-sprayed（CSed） AA2024/Al2 O3 metal matrix composites（MMCs）. Three different rotation speeds with a constant traverse speed were used for FSP. Microstructural analysis of the FSPed specimens reveals significant Al2 O3 particle refinement and improved particle distribution over the as-sprayed deposits. After FSP, a microstructural and mechanical gradient MMC through the thickness direction was obtained. Therefore, a hybrid technique combining these two solid-state processes, i.e. CS and FSP, was proposed to produce functionally gradient deposits. The Guinier-Preston-Bagaryatskii zone was dissolved during FSP, while the amounts at different rotation speeds were approximately the same, which is possibly due to the excellent thermal conductivity of the used Cu substrate. Mechanical property tests confirm that FSP can effectively improve the tensile performance and Vickers hardness of CSed AA2024/Al2 O3 MMCs. The properties can be further enhanced with a larger rotation speed with a maximum increase of 25.9% in ultimate tensile strength and27.4% in elongation at 1500 rpm. Friction tests show that FSP decreases the wear resistance of CSed MMCs deposits due to the breakup of Al2 O3 particles. The average values and fluctuations of friction coefficients at different rotation speeds vary significantly.展开更多
The mechanical properties of metal yttrium such as strength, plasticity, hardness and elasticity were introduced . The purifying techniques of yttrium were discussed in detail. The processing methods for metal yttrium...The mechanical properties of metal yttrium such as strength, plasticity, hardness and elasticity were introduced . The purifying techniques of yttrium were discussed in detail. The processing methods for metal yttrium including extruding, forging, rolling, wiredrawing and welding were also introduced. Finally, the potential use of yttrium and its alloys were prospected.展开更多
The enlarged production scale of underground non-ferrous metal mines is affected by many uncertain factors difficult to describe mathematically with any level of accuracy.The problem can be solved by a synthesis of ar...The enlarged production scale of underground non-ferrous metal mines is affected by many uncertain factors difficult to describe mathematically with any level of accuracy.The problem can be solved by a synthesis of artificial intelligence.Based on the analysis of the major factors affecting the scale of enlarged production,we first interpreted in detail the design principles and structure of the intelligent system.Secondly,we introduced an ANN subsystem.In order to ensure technological and scale efficien- cies of the training samples for ANN,we filtrated the samples with a DEA method.Finally,we trained the intelligent system,which was proved to be very efficient.展开更多
基金supported by the National Key Research and Development Project(Nos.2019YFC1804503 and 2019YFC1804504)the National Natural Science Foundation of China(No.41731279)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01Z032).
文摘Non-ferrous metal smelting poses significant risks to public health.Specifically,the copper smelting process releases arsenic,a semi-volatile metalloid,which poses an emerging exposure risk to both workers and nearby residents.To comprehensively understand the internal exposure risks of metal(loid)s from copper smelting,we explored eighteen metal(loid)s and arsenic metabolites in the urine of both occupational and non-occupational populations using inductively coupled plasma mass spectrometry with high-performance liquid chromatography and compared their health risks.Results showed that zinc and copper(485.38 and 14.00μg/L),and arsenic,lead,cadmium,vanadium,tin and antimony(46.80,6.82,2.17,0.40,0.44 and 0.23μg/L,respectively)in workers(n=179)were significantly higher compared to controls(n=168),while Zinc,tin and antimony(412.10,0.51 and 0.15μg/L,respectively)of residents were significantly higher than controls.Additionally,workers had a higher monomethyl arsenic percentage(MMA%),showing lower arsenic methylation capacity.Source appointment analysis identified arsenic,lead,cadmium,antimony,tin and thallium as co-exposure metal(loid)s from copper smelting,positively relating to the age of workers.The hazard index(HI)of workers exceeded 1.0,while residents and control were approximately at 1.0.Besides,all three populations had accumulated cancer risks exceeding 1.0×10^(-4),and arsenite(AsIII)was the main contributor to the variation of workers and residents.Furthermore,residents living closer to the smelting plant had higher health risks.This study reveals arsenic exposure metabolites and multiple metals as emerging contaminants for copper smelting exposure populations,providing valuable insights for pollution control in non-ferrous metal smelting.
基金The Major Technologies R&D Special Program of Anhui,China(Grant No.16030901060)The National Natural Science Foundation of China(Grant No.61502010)+1 种基金The Natural Science Foundation of Anhui Province(Grant No.1608085QF146)The Natural Science Foundation of China(Grant No.61806004).
文摘To acquire non-ferrous metals related news from different countries’internet,we proposed a cross-lingual non-ferrous metals related news recognition method based on CNN with a limited bilingual dictionary.Firstly,considering the lack of related language resources of non-ferrous metals,we use a limited bilingual dictionary and CCA to learn cross-lingual word vector and to represent news in different languages uniformly.Then,to improve the effect of recognition,we use a variant of the CNN to learn recognition features and construct the recognition model.The experimental results show that our proposed method acquires better results.
基金Supported by Foundation for University Key Teacher by the Ministry of Education
文摘The low melting point metallic tin powder or alloy of tin and lead was blended with polypropylene. A kind of in situ composite has been prepared. The variations of torque were studied when the composites were mixed in Haake torque rheogeniometer. By way of capillary extrusion, effects upon rheology of the in situ composites of the low melting point metals (LMPM) and coupling agent for their different variety and content, were investigated. From flow curves, the results indicate that in situ composites mixed with the LMPM are a kind of pseudoplastic fluid. If the LMPM were melted, the higher the content of the LMPM, the lower apparent viscosity of composites. Meanwhile, when the coupling agent is added into composites , the viscosity of composite will go up first and drop then. This shows that the LMPM have a promoter flow action on the polypropylene.
文摘The Rare Earths Research Institute(the former Rare Earths Research Laboratory)under the GRINM,the first institute to conduct R&D for rare earths(RE)industry in China,was founded in 1958.The Institutewas mainly engaged in the research work of comprehensive utilization of the mine at Baiyun-ebo,the largest
文摘The Rare Earths Research Institute(the former Rare Earths Research Laboratory)under the GRINM,the first institute to conduct R&D for rare earths(RE)industry in China,was founded in 1958.The Institutewas mainly engaged in the research work of comprehensive utilization of the mine at Baiyun-ebo,the largestRE mine in the world,and the ion adsorption type RE mineral in southern China.The ore decomposition,
文摘The waste products, such as induction furnace slag, ladle furnace slag, air pollution control dust, and ramming mass collected from major iron processing industries in Chittagong, Bangladesh were analyzed for heavy metals and naturally radioactive elements. The concentrations of heavy metals Fe, Cr, Mn, Co, Cd, Ni, Pb, Cu and Zn were obtained from atomic absorption spectrophotometer (AAS) analysis with flame atomizer and the radioactivities due to 226Ra, 232Th and 40K were determined using high purity germanium (HPGe) detector of well shielded gamma-ray counting system. From the mean specific activities of the above three natural radionuclides in the investigated samples, the radium equivalent activity (Raeq) and the external hazard index (Hex) were calculated. The study showed the prospect of contamination of environmental materials (viz., soil, water, air, plant) due to many of these investigated elements by using the collected waste products in landfill. The chemical process of ion exchange indicates that the elevated heavy metals in soil can play a role to increase the natural radioactivity of the soil. The obtained Raeq as well as Hex indicated the insignificant radiation hazard due to the activities of primordial radionuclides found in the investigated samples.
文摘China’s non-ferrous metals industry has constantly maintained a steady, rapid and healthy development since the reform and opening to the outside world. By the end of 1994, the annual output often kinds of common non-ferrous metals such as copper, aluminium, lead, and zinc had reached 3.701 million tons, a 12.2 percent increase over the previous year; the qualification rate of principal products and the output value rate of good quality products all achieved an increase over the previous year. China has
文摘Since the beginning of the 1990s, the China non-ferrous metals export trade has steadily increased, foreign economic and technical cooperation has further expanded and foreign capital utilization and overseas development have achieved new breakthroughs.
文摘Vice president of China National Nonferrous Metals Industries Corporation Mr. WoTingshu said:"The output of 10 kinds of nonferrous metals amounted to 2.45 Mt." This factmean1s that the national plan for nonferrous metals production fulfiled earlier. The 10 kinds ofnonferrous metals are aluminium, magnesium, lead, zinc, copper, tin, nickel, antimony mercuryand titanium.
文摘The China Non-ferrous MetalsIndustry Corporation has putforward ten development policiesfor the Ninth Five-year Plan period,according to the central government’sinstruction to change the way of economicgrowth,and raise the integral quality andbenefit of the national economy:
文摘Since the the launch of theeconomic reform and openingdrive,especially the foundingof the China Non-ferrous MetalsIndustry Corporation,China’s non-ferrous metals industry hassustained rapid and healthy growth.
文摘Several pillar industries in the national economy, including non-ferrous metal metallurgy industry. However, with the rapid growth of the metallurgical industry, the recycling technology has not been reformed in time, resulting in frequent environmental pollution. For example, metal waste residue or waste liquid cannot be completely recycled and treated. Therefore, "environmental protection" and "green" have become particularly important issues, and environmental issues also determine the future survival and development of mankind. In this paper, the author mainly studies the non-ferrous metal metallurgy and the urgent need through the environmental protection method, and on this basis, explores the green environmental protection metallurgy method, and gives the related suggestion.
基金the support of the National Basic Research Program,China(Grant Nos.2011CB932603 and 2012CB619600)the National Natural Science Foundation, China(Grant No.51331008)
文摘A route combining powder metallurgy and subsequent friction stir processing was utilized to fabricate carbon nanotube （CNT） reinforced AI （CNT/AI） and 6061AI （CNT/6061AI） composites. Microstructural observations indicated that CNTs were uniformly dispersed in the matrix in both CNT/AI and CNT/6061AI composites. Mg and Si elements tended to segregate at CNT-AI interfaces in the CNT/6061AI composite during artificial aging treatment. The tensile properties of both the AI and 6061AI were increased by CNT incorporation. The electrical conductivity of CNT/AI was decreased by CNT addition, while CNT/6061AI exhibited an increase in electrical conductivity due to the Mg and Si segregation.
基金supported by the National Key R&D Program of China (No. 2017YFC0210500)the National Natural Science Foundation of China (No. 51508525)the Key Research and Development Program of Ningxia Hui Autonomous Region (No. 2016KJHM31)
文摘Hierarchical Ag-SiO_2@Fe_3O_4 magnetic composites were selected for elemental mercury(Hg^0) removal from non-ferrous metal smelting flue gas in this study. Results showed that the hierarchical Ag-SiO_2@Fe_3O_4 magnetic composites had favorable Hg^0 removal ability at low temperature. Moreover, the adsorption capacity of hierarchical magnetic composite is much larger than that of pure Fe_3O_4 and SiO_2@Fe_3O_4. The Hg^0 removal efficiency reached the highest value as approximately 92% under the reaction temperature of 150°C, while the removal efficiency sharply reduced in the absence of O_2. The characterization results indicated that Ag nanoparticles grew on the surface of SiO_2@Fe_3O_4 support. The large surface area of SiO_2 supplied efficient reaction room for Hg and Ag atoms. Ag–Hg amalgam is generated on the surface of the composites. In addition, this magnetic material could be easily separated from fly ashes when adopted for treating real flue gas, and the spent materials could be regenerated using a simple thermal-desorption method.
文摘The Nanling region is an important nonferrous and rare metal metallogenic province in South China, in which most of the deposits are related to granitoids in genesis. It covers southern Hunan, southern Jiangxi, Guangxi, Guangdong and Fujian provinces, with a total area of about 550,000 km2. This metallogenic province is well known in the world for its rich tungsten and tin resources. In the past 40-odd years, a vast amount of mineral exploration activities and studies of the geology of mineral deposits have been carried out and great achievements obtained in the province. This paper is focused on a discussion about the deep tectonic processes in the orogenic belt during the Mesozoic and their contribution to the superaccumulation of metals. Tectonically, this metallogenic province is composed of three units: (1) the marginal continental orogenic belt in the Southeastern Coast fold system in the Yanshanian; (2) the intercontinental orogenic belt in the collision suture belt between the Yangtze and Cathay-sian plates mainly in the Caledonian; and (3) the intracontinental orogenic belt induced by subduction of the ocean crust and delimination of the mantle lithosphere in the Yanshanian. It is suggested that superaccumulation of metals in this metallogenic province was caused by the existence of mantle rooted tectonics at the depth based on comprehensive studies of geophysical information of seismic, geothermal and magnetotelluric surveys in Nanling and its adjacent areas. The Xihuashan wolframite quartz vein deposit, the Shizhuyuan W, Sn, Mo, Bi greisen-skarn deposit and the Dachang tin-polymetallic deposit are three typical examples of the deep tectonic processes. However, this kind of deep tectonic processes only act as the 'engine' of the superaccumulation of metals, which means that they should have to correspond with the super-crust ore-controlling pattern of 'lines-rows-clusters' (L-R-C). This recog-nization is expected to play an important role in assessment of mineral resources in this province.
基金financially by the National Key Research and Development Program of China (No. 2016YFB1100104)the Fund of SAST (No. SAST2016043)the 111 Project (No. B08040)
文摘In this study, friction stir processing（FSP） was employed to modify cold-sprayed（CSed） AA2024/Al2 O3 metal matrix composites（MMCs）. Three different rotation speeds with a constant traverse speed were used for FSP. Microstructural analysis of the FSPed specimens reveals significant Al2 O3 particle refinement and improved particle distribution over the as-sprayed deposits. After FSP, a microstructural and mechanical gradient MMC through the thickness direction was obtained. Therefore, a hybrid technique combining these two solid-state processes, i.e. CS and FSP, was proposed to produce functionally gradient deposits. The Guinier-Preston-Bagaryatskii zone was dissolved during FSP, while the amounts at different rotation speeds were approximately the same, which is possibly due to the excellent thermal conductivity of the used Cu substrate. Mechanical property tests confirm that FSP can effectively improve the tensile performance and Vickers hardness of CSed AA2024/Al2 O3 MMCs. The properties can be further enhanced with a larger rotation speed with a maximum increase of 25.9% in ultimate tensile strength and27.4% in elongation at 1500 rpm. Friction tests show that FSP decreases the wear resistance of CSed MMCs deposits due to the breakup of Al2 O3 particles. The average values and fluctuations of friction coefficients at different rotation speeds vary significantly.
文摘The mechanical properties of metal yttrium such as strength, plasticity, hardness and elasticity were introduced . The purifying techniques of yttrium were discussed in detail. The processing methods for metal yttrium including extruding, forging, rolling, wiredrawing and welding were also introduced. Finally, the potential use of yttrium and its alloys were prospected.
基金Project 50374005 supported by the National Natural Science Foundation of China
文摘The enlarged production scale of underground non-ferrous metal mines is affected by many uncertain factors difficult to describe mathematically with any level of accuracy.The problem can be solved by a synthesis of artificial intelligence.Based on the analysis of the major factors affecting the scale of enlarged production,we first interpreted in detail the design principles and structure of the intelligent system.Secondly,we introduced an ANN subsystem.In order to ensure technological and scale efficien- cies of the training samples for ANN,we filtrated the samples with a DEA method.Finally,we trained the intelligent system,which was proved to be very efficient.
