Permanently shadowed regions(PSRs)on the Moon are potential reservoirs for water ice,making them hot spots for future lunar exploration.The water ice in PSRs would cause distinctive changes in space weathering there,i...Permanently shadowed regions(PSRs)on the Moon are potential reservoirs for water ice,making them hot spots for future lunar exploration.The water ice in PSRs would cause distinctive changes in space weathering there,in particular reduction-oxidation processes that diff er from those in illuminated regions.To determine the characteris-tics of products formed during space weathering in PSRs,the lunar meteorite NWA 10203 with artifi cially added water was irradiated with a nanosecond laser to simulate a micro-meteorite bombardment of lunar soil containing water ice.The TEM results of the water-incorporated sample showed distinct amorphous rims that exhibited irregular thickness,poor stratifi cation,the appearance of bubbles,and a reduced number of npFe^(0).Additionally,EELS analysis showed the presence of ferric iron at the rim of the nanophase metallic iron particles(npFe^(0))in the amorphous rim with the involve-ment of water.The results suggest that water ice is another possible factor contributing to oxidation during microme-teorite bombardment on the lunar surface.In addition,it off ers a reference for a new space weathering model that incorporates water in PSRs,which could be widespread on asteroids with volatiles.展开更多
Fine nickel ferrite precursors NiFe2(C204)3·6H2O were obtained via co-precipitation method with low grade nickel matte as the raw material. Thermodynamic analysis of NiClz-FeC12-(NH4)2C204-H20 system for prec...Fine nickel ferrite precursors NiFe2(C204)3·6H2O were obtained via co-precipitation method with low grade nickel matte as the raw material. Thermodynamic analysis of NiClz-FeC12-(NH4)2C204-H20 system for precipitation identified that the theoretical optimum co-precipitation pH value is 2, and C2O2 has strong complexation with Ni2+ and Fe2+ ions. Based on these theoretical considerations, the effects of parameters on the precipitation rates and precursors size were investigated systematically. The results show that the optimum co-precipitation conditions are pH=2, temperature 45 ℃, 1.2 times theoretical amount of (NH4)2C204 dosage and 3% PEG400 addition. Under these conditions, the precipitation rates of Ni2+ and Fe2+ are both over 99.8%, with the precursors size of 1-2 urn. Furthermore, X-ray diffraction (XRD) and thermogravimetry-differential thermal analysis (TG-DTA) demonstrate that the precursors are single-phase solid solution, wherein the nickel/iron atoms are replaced by the iron/nickel atoms reciprocally.展开更多
In the newly developed oxygen-enriched bottom-blowing copper smelting process(also known as the SKS copper smelting process), Cu loss in slag is one of the most concerning issues. This paper presents our research resu...In the newly developed oxygen-enriched bottom-blowing copper smelting process(also known as the SKS copper smelting process), Cu loss in slag is one of the most concerning issues. This paper presents our research results concerning the relationship between the Cu content of the matte and slag in the SKS process; the results are based on actual industrial production in the Dongying Fangyuan copper smelter. The results show that the matte grade strongly influences Cu losses in slag. The dissolved and entrained losses account for 10%–20% and 80%–90% of the total SKS industrial Cu losses in slag, respectively. With increasing matte grade, the dissolved and entrained Cu losses in the SKS slag both increase continuously. When the matte grade is greater than 68%, the content of Cu in the smelting slag increases much more dramatically. To obtain a high direct recovery of copper, the matte grade should be less than 75% in industrial SKS copper production.展开更多
A calcified roasting-acid leaching process was developed as a highly effective method for the extraction of valuable metals from low nickel matte in the presence of CaO additive. The influences of process parameters o...A calcified roasting-acid leaching process was developed as a highly effective method for the extraction of valuable metals from low nickel matte in the presence of CaO additive. The influences of process parameters on the metal extraction were studied, including the roasting temperature, roasting time, addition of CaO, H2SO4 concentration and liquid-solid ratio. Under the optimum condition, 94.2% of Ni, 98.1% of Cu, 92.2% of Co and 89.3% of Fe were recovered. Additionally, 99.6% of Fe was removed from the leachate as goethite by a subsequent goethite iron precipitation process. The behavior and mechanism of CaO additive in the roasting process was clarified. The role of CaO is to prevent the formation of nonferrous metal ferrite phases by a preferential reaction with Fe2O3 during the roasting process. The metal oxides(Cu O and NixCu1-xO) remained stable during high-temperature roasting and were subsequently efficiently leached using a sulfuric acid solution.展开更多
This paper describes the structure and function of the intelligent decision support system (IDSS) on the process of nickel matte smelter. The knowledge and model base system based on fuzzy-decision rules ale specially...This paper describes the structure and function of the intelligent decision support system (IDSS) on the process of nickel matte smelter. The knowledge and model base system based on fuzzy-decision rules ale specially suggested. The IDSS possesses the self-learning and adaptive properties, andhas been used for managing and analyzing the production information, optimizing the composition of the charge mixture, and deciding the optimal operational conditions. Electric energy consumption has been reduced remarkably and the yield of nickel has been increased.展开更多
The leaching of low-sulfur Ni-Cu matte in acid-oxygen(CuSO4-H2SO4-O2)solution at atmospheric pressure was researched.This matte was obtained from high grade Ni-Cu matte by magnetic separation,which mainly contained Ni...The leaching of low-sulfur Ni-Cu matte in acid-oxygen(CuSO4-H2SO4-O2)solution at atmospheric pressure was researched.This matte was obtained from high grade Ni-Cu matte by magnetic separation,which mainly contained Ni-Cu alloy and a small quantity of sulfides.The effects of temperature,agitation speed,oxygen flow rate,particle size,acid concentration and concentration of copper ion were studied.It is found that the matte particles are leached by shrinking core mechanism and the leaching process is electrochemically controlled.In a temperature range of 30-60℃,the surface reaction is rate-limiting step,with an apparent activation energy of 41.9 kJ/mol.But at higher temperature(70-85℃),the rate process is controlled by diffusion through the product layer,with an apparent activation energy of 7.3 kJ/mol.展开更多
An adaptive chaotic gradient descending optimization algorithm for single objective optimization was presented. A local minimum judged by two rules was obtained by an improved mutative-step gradient descending method....An adaptive chaotic gradient descending optimization algorithm for single objective optimization was presented. A local minimum judged by two rules was obtained by an improved mutative-step gradient descending method. A new optimal minimum was obtained to replace the local minimum by mutative-scale chaotic search algorithm whose scales are magnified gradually from a small scale in order to escape local minima. The global optimal value was attained by repeatedly iterating. At last, a BP (back-propagation) neural network model for forecasting slag output in matte converting was established. The algorithm was used to train the weights of the BP neural network model. The simulation results with a training data set of 400 samples show that the training process can be finished within 300 steps to obtain the global optimal value, and escape local minima effectively. An optimization system for operation parameters, which includes the forecasting model, is achieved, in which the output of converter increases by 6.0%, and the amount of the treated cool materials rises by 7.8% in the matte converting process.展开更多
Environment matting and compositing is a technique to extract a foreground object, including color, opacity, reflec- tive and refractive properties, from a real-world scene, and synthesize new images by placing it int...Environment matting and compositing is a technique to extract a foreground object, including color, opacity, reflec- tive and refractive properties, from a real-world scene, and synthesize new images by placing it into new environments. The description of the captured object is named environment matte. Recent matting and compositing techniques can produce quite realistic images for objects with complex optical properties. This paper presents an approximate method to transform the matte by simulating variation of the foreground object’s refractive index. Our algorithms can deal with achromatous-and-transparent ob- jects and the experimental results are visually acceptable. Our idea and method can be applied to produce some special video effects, which could be very useful in film making, compared with the extreme difficulty of physically changing an object’s refractive index.展开更多
Due to the importance of detecting the matte grade in the copper flash smelting process, the mechanism model was established according to the multi-phase and multi-component mathematic model. Meanwhile this procedure ...Due to the importance of detecting the matte grade in the copper flash smelting process, the mechanism model was established according to the multi-phase and multi-component mathematic model. Meanwhile this procedure was a complicated production process with characteristics of large time delay, nonlinearity and so on. A fuzzy neural network model was set up through a great deal of production data. Besides a novel constrained gradient descent algorithm used to update the parameters was put forward to improve the parameters learning efficiency. Ultimately the self-adaptive combination technology was adopted to paralleled integrate two models in order to obtain the prediction model of the matte grade. Industrial data validation shows that the intelligently integrated model is more precise than a single model. It can not only predict the matte grade exactly but also provide optimal control of the copper flash smelting process with potent guidance.展开更多
Based on the facts that cations and anions of molten salts and binary basic oxide solid solutions do not separate from each other as well as that the electric conductivities of mattes are greater than that of salts an...Based on the facts that cations and anions of molten salts and binary basic oxide solid solutions do not separate from each other as well as that the electric conductivities of mattes are greater than that of salts and basic oxide solid solutions, the calculating models of mass action concentrations for binary and ternary mattes involving eutectic have been formulated. The results of calculation agree well with the values measured;this in turn shows that the calculating models can reftect the structural characteristics of the mattes concerned.展开更多
基金support from the Youth Innovation Promotion Association,Chinese Academy of Sciences(2020395)Strategic Priority Research Program of the Chinese Academy of Sciences grant XDB 41000000(Y.L.)+4 种基金National Natural Science Foundation of China(Nos.42273042 and 41931077)"From 0 to 1"Original Exploration Cultivation Project,Institute of Geochemistry,Chinese Academy of Sciences(DHSZZ2023-3)Guizhou Provincial Foundation for Excellent Scholars Program(No.GCC[2023]088)Guizhou Provincial Science and Technology Projects:QKHJCZK[2023]-General 473NSFC Young Scientist Fund(Nos.42303041 and 42403043)。
文摘Permanently shadowed regions(PSRs)on the Moon are potential reservoirs for water ice,making them hot spots for future lunar exploration.The water ice in PSRs would cause distinctive changes in space weathering there,in particular reduction-oxidation processes that diff er from those in illuminated regions.To determine the characteris-tics of products formed during space weathering in PSRs,the lunar meteorite NWA 10203 with artifi cially added water was irradiated with a nanosecond laser to simulate a micro-meteorite bombardment of lunar soil containing water ice.The TEM results of the water-incorporated sample showed distinct amorphous rims that exhibited irregular thickness,poor stratifi cation,the appearance of bubbles,and a reduced number of npFe^(0).Additionally,EELS analysis showed the presence of ferric iron at the rim of the nanophase metallic iron particles(npFe^(0))in the amorphous rim with the involve-ment of water.The results suggest that water ice is another possible factor contributing to oxidation during microme-teorite bombardment on the lunar surface.In addition,it off ers a reference for a new space weathering model that incorporates water in PSRs,which could be widespread on asteroids with volatiles.
基金Project(2012BAB10B04) supported by National Key Technology R&D Program of ChinaProject supported by Hunan Provincial Innovation Foundation for Postgraduate,China
文摘Fine nickel ferrite precursors NiFe2(C204)3·6H2O were obtained via co-precipitation method with low grade nickel matte as the raw material. Thermodynamic analysis of NiClz-FeC12-(NH4)2C204-H20 system for precipitation identified that the theoretical optimum co-precipitation pH value is 2, and C2O2 has strong complexation with Ni2+ and Fe2+ ions. Based on these theoretical considerations, the effects of parameters on the precipitation rates and precursors size were investigated systematically. The results show that the optimum co-precipitation conditions are pH=2, temperature 45 ℃, 1.2 times theoretical amount of (NH4)2C204 dosage and 3% PEG400 addition. Under these conditions, the precipitation rates of Ni2+ and Fe2+ are both over 99.8%, with the precursors size of 1-2 urn. Furthermore, X-ray diffraction (XRD) and thermogravimetry-differential thermal analysis (TG-DTA) demonstrate that the precursors are single-phase solid solution, wherein the nickel/iron atoms are replaced by the iron/nickel atoms reciprocally.
基金financially supported by the National Natural Science Foundation of China (No. 51620105013)Dongying Fangyuan Nonferrous Metals Co., Ltd.
文摘In the newly developed oxygen-enriched bottom-blowing copper smelting process(also known as the SKS copper smelting process), Cu loss in slag is one of the most concerning issues. This paper presents our research results concerning the relationship between the Cu content of the matte and slag in the SKS process; the results are based on actual industrial production in the Dongying Fangyuan copper smelter. The results show that the matte grade strongly influences Cu losses in slag. The dissolved and entrained losses account for 10%–20% and 80%–90% of the total SKS industrial Cu losses in slag, respectively. With increasing matte grade, the dissolved and entrained Cu losses in the SKS slag both increase continuously. When the matte grade is greater than 68%, the content of Cu in the smelting slag increases much more dramatically. To obtain a high direct recovery of copper, the matte grade should be less than 75% in industrial SKS copper production.
基金Projects(U1860203,U1860108,51574164) supported by the National Natural Science Foundation of China
文摘A calcified roasting-acid leaching process was developed as a highly effective method for the extraction of valuable metals from low nickel matte in the presence of CaO additive. The influences of process parameters on the metal extraction were studied, including the roasting temperature, roasting time, addition of CaO, H2SO4 concentration and liquid-solid ratio. Under the optimum condition, 94.2% of Ni, 98.1% of Cu, 92.2% of Co and 89.3% of Fe were recovered. Additionally, 99.6% of Fe was removed from the leachate as goethite by a subsequent goethite iron precipitation process. The behavior and mechanism of CaO additive in the roasting process was clarified. The role of CaO is to prevent the formation of nonferrous metal ferrite phases by a preferential reaction with Fe2O3 during the roasting process. The metal oxides(Cu O and NixCu1-xO) remained stable during high-temperature roasting and were subsequently efficiently leached using a sulfuric acid solution.
文摘This paper describes the structure and function of the intelligent decision support system (IDSS) on the process of nickel matte smelter. The knowledge and model base system based on fuzzy-decision rules ale specially suggested. The IDSS possesses the self-learning and adaptive properties, andhas been used for managing and analyzing the production information, optimizing the composition of the charge mixture, and deciding the optimal operational conditions. Electric energy consumption has been reduced remarkably and the yield of nickel has been increased.
基金Project(50774020) supported by the National Natural Science Foundation of China
文摘The leaching of low-sulfur Ni-Cu matte in acid-oxygen(CuSO4-H2SO4-O2)solution at atmospheric pressure was researched.This matte was obtained from high grade Ni-Cu matte by magnetic separation,which mainly contained Ni-Cu alloy and a small quantity of sulfides.The effects of temperature,agitation speed,oxygen flow rate,particle size,acid concentration and concentration of copper ion were studied.It is found that the matte particles are leached by shrinking core mechanism and the leaching process is electrochemically controlled.In a temperature range of 30-60℃,the surface reaction is rate-limiting step,with an apparent activation energy of 41.9 kJ/mol.But at higher temperature(70-85℃),the rate process is controlled by diffusion through the product layer,with an apparent activation energy of 7.3 kJ/mol.
基金financially supported by the National Basic Research Priorities Program of China(Nos.2014CB643401 and 2013AA032003)the National Natural Science Foundation of China(No.51372019)Shanxi Collaborative Innovation Center of High Value-added Utilization of Coal-related Wastes
文摘An adaptive chaotic gradient descending optimization algorithm for single objective optimization was presented. A local minimum judged by two rules was obtained by an improved mutative-step gradient descending method. A new optimal minimum was obtained to replace the local minimum by mutative-scale chaotic search algorithm whose scales are magnified gradually from a small scale in order to escape local minima. The global optimal value was attained by repeatedly iterating. At last, a BP (back-propagation) neural network model for forecasting slag output in matte converting was established. The algorithm was used to train the weights of the BP neural network model. The simulation results with a training data set of 400 samples show that the training process can be finished within 300 steps to obtain the global optimal value, and escape local minima effectively. An optimization system for operation parameters, which includes the forecasting model, is achieved, in which the output of converter increases by 6.0%, and the amount of the treated cool materials rises by 7.8% in the matte converting process.
基金Project supported by the National Natural Science Foundation of China (No. 60403044) and Microsoft Research Asia (PROJECT-2004-IMAGE-01)
文摘Environment matting and compositing is a technique to extract a foreground object, including color, opacity, reflec- tive and refractive properties, from a real-world scene, and synthesize new images by placing it into new environments. The description of the captured object is named environment matte. Recent matting and compositing techniques can produce quite realistic images for objects with complex optical properties. This paper presents an approximate method to transform the matte by simulating variation of the foreground object’s refractive index. Our algorithms can deal with achromatous-and-transparent ob- jects and the experimental results are visually acceptable. Our idea and method can be applied to produce some special video effects, which could be very useful in film making, compared with the extreme difficulty of physically changing an object’s refractive index.
基金Project(60634020) supported by the National Natural Science Foundation of ChinaProject(2002CB312200) supported by the National Basic Research and Development Program of China
文摘Due to the importance of detecting the matte grade in the copper flash smelting process, the mechanism model was established according to the multi-phase and multi-component mathematic model. Meanwhile this procedure was a complicated production process with characteristics of large time delay, nonlinearity and so on. A fuzzy neural network model was set up through a great deal of production data. Besides a novel constrained gradient descent algorithm used to update the parameters was put forward to improve the parameters learning efficiency. Ultimately the self-adaptive combination technology was adopted to paralleled integrate two models in order to obtain the prediction model of the matte grade. Industrial data validation shows that the intelligently integrated model is more precise than a single model. It can not only predict the matte grade exactly but also provide optimal control of the copper flash smelting process with potent guidance.
文摘Based on the facts that cations and anions of molten salts and binary basic oxide solid solutions do not separate from each other as well as that the electric conductivities of mattes are greater than that of salts and basic oxide solid solutions, the calculating models of mass action concentrations for binary and ternary mattes involving eutectic have been formulated. The results of calculation agree well with the values measured;this in turn shows that the calculating models can reftect the structural characteristics of the mattes concerned.