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
During the COVID-19 pandemic,the international financial markets experienced severe turbulence.Under the background of“Made in China 2025”,substantial entity enterprises have a large demand for non-ferrous metals.Wi...During the COVID-19 pandemic,the international financial markets experienced severe turbulence.Under the background of“Made in China 2025”,substantial entity enterprises have a large demand for non-ferrous metals.With the enhancement of financial attributes of non-ferrous metals,it is vital to prevent financial systemic risk contagion in the non-ferrous metal markets.In this article,the ensemble empirical mode decomposition method is used to decompose the prices of eight important non-ferrous metals futures,and then the dynamic DY risk spillover index model is established from the perspectives of long-term and short-term.The risk spillover between non-ferrous metals during the COVID-19 is quantitatively analyzed from different frequency domains.The study finds that in the long run,the risk spillover relationship between non-ferrous metals remained basically stable,and the change of it after the epidemic is slight.In the short run,the risk spillover relationship has different degrees of structural changes after the outbreak of the COVID-19 pandemic.The ensemble empirical mode decomposition method can distinguish the risk spillovers in different cycles,and help to formulate policies for preventing systemic risks in the non-ferrous metal markets according to the different length of terms.展开更多
Spectral analysis was a method of identifying substances, determining their chemical composition and calculating their content based on their spectral characteristics. This paper mainly discussed the application of va...Spectral analysis was a method of identifying substances, determining their chemical composition and calculating their content based on their spectral characteristics. This paper mainly discussed the application of various spectroscopic techniques, mainly including atomic absorption spectrometry (AAS) inductively coupled plasma emission spectrometry (ICP-AES) X-ray fluorescence spectroscopy (XRF) atomic fluorescence spectroscopy (AFS) direct reading spectroscopy (OES) glow discharge emission spectroscopy (GD-OSE) laser-induced breakdown spectroscopy (LIBS), in the formulation of non-ferrous metal standards in China. The AAS method was the most widely used single-element microanalysis method among the non-ferrous metal standards. The ICP-AES method was good at significant advantages in the simultaneous detection of multiple elements. The XRF method was increasingly used in the determination of primary and secondary trace elements due to its simple sample preparation and high efficiency. The AFS was mostly detected by single-element trace analysis. OES GD-OES and LIBS were playing an increasingly important role in the new demand area for non-ferrous metals. This paper discussed matrix elimination, sample digestion, sample preparation, instrument categories and other aspects of some standards, and summarized the advantages of spectral analysis and traditional chemical analysis methods. The new methods of future spectroscopic technology had been illustrated in the process of developing non-ferrous metal standards.展开更多
The bottom ashes resulted annually from the incineration of municipal solid waste in Europe contain about 400,000 tonnes of metallic aluminium and 200,000 tonnes of heavy non-ferrous metals, such as copper and zinc. E...The bottom ashes resulted annually from the incineration of municipal solid waste in Europe contain about 400,000 tonnes of metallic aluminium and 200,000 tonnes of heavy non-ferrous metals, such as copper and zinc. Efficient recovery of this non-ferrous metal resource requires state-of-the-art separation technologies and a continuous feedback of laboratory analyses of the metal products and the depleted bottom ash to the operators of the bottom ash treatment plants. A methodology is presented for the optimization of the production of non-ferrous metal value from Municipal Solid Waste Incinerator bottom ash. Results for an incineration plant in the Netherlands show that efficient recycling can have a significant impact on value recovery as well as on non-ferrous metal recycling rates, producing up to 8% more revenue and 25% more metals from the ash.展开更多
Cadmium(Cd)has received widespread attention owing to its persistent toxicity and non-degradability.Cd in the human body is mainly absorbed from the external environment and is usually assessed using urinary Cd.Hunan ...Cadmium(Cd)has received widespread attention owing to its persistent toxicity and non-degradability.Cd in the human body is mainly absorbed from the external environment and is usually assessed using urinary Cd.Hunan Province is the heartland of the Chinese non-ferrous mining area,where several serious Cd pollution events have occurred,including high levels of Cd in the urine of residents.However,the environmental factors influencing high urinary Cd levels(UCLs)in nearby residents remain unclear.Therefore,211 nearby residents’UCLs and the corresponding sociological characteristics from nine groundwater samples in this area were analyzed using statistical analysis models.Groundwater Cd concentration ranged from 0.02 to 1.15μg/L,aligning with class III of the national standard;the range of UCL of nearby residents was 0.37–36.60μg/L,exceeding the national guideline of 0–2.5μg/L.Groundwater Cd levels were positively correlated with the UCL(P<0.001,correlation coefficient 95%CI=9.68,R^(2)=0.06).In addition,sociological characteristics,such as smoking status and education level,also affect UCL.All results indicate that local governments should strengthen the prevention and abatement of groundwater Cd pollution.This study is the first to systematically evaluate the relationship between groundwater Cd and UCL using internal and external environmental exposure data.These findings provide essential bases for relevant departments to reduce Cd exposure in regions where the heavy metal industry is globally prevalent.展开更多
This study reports on the impact of the curing conditions on the mechanical properties and leaching of inorganic polymer （IP） mortars made from a water quenched fayalitic slag. Three similar IP mortars were produced...This study reports on the impact of the curing conditions on the mechanical properties and leaching of inorganic polymer （IP） mortars made from a water quenched fayalitic slag. Three similar IP mortars were produced by mixing together slag, aggregate and activating solution, and cured in three different environments for 28 d： a） at 20℃ and relative humidity （RH） - 50% （T20RH50）, b） at 20℃and RH≥90% （T20RH90） and c） at 60℃ and RH - 20% （T60RH20）. Compressive strength （EN 196-1） varied between 19 MPa （T20RH50） and 31 MPa （T20RH90）. This was found to be attributed to the cracks formed upon curing. Geochemical modelling and two leaching tests were performed, the EA NEN 7375 tank test, and the BS EN 12457-1 single batch test. Results show that Cu, Ni, Pb, Zn andAs leaching occurred even at high pH, which varied between 10 and 11 in the tank test＇s leachates and between 12 and 12.5 in the single batch＇s leachates. Leaching values obtained were below the requirements for non-shaped materials of Flemish legislation for As, Cu and Ni in the single batch test.展开更多
Air pollutant emissions represent a critical challenge in the green development of the non-ferrous metallurgy industry.This work studied the emission characteristics,formation mechanisms,phase transformation and separ...Air pollutant emissions represent a critical challenge in the green development of the non-ferrous metallurgy industry.This work studied the emission characteristics,formation mechanisms,phase transformation and separation of typical air pollutants,such as heavy metal particles,mercury,sulfur oxides and fluoride,during non-ferrous smelting.A series of purification technologies,including optimization of the furnace throat and hightemperature discharge,were developed to collaboratively control and recover fine particles from the flue gas of heavy metal smelting processes,including copper,lead and zinc.Significant improvements have been realized in wet scrubbing technology for removing mercury,fluoride and SO_(2)from flue gas.Gas-liquid sulfidation technology by applying H_(2)S was invented to recycle the acid scrubbing wastewater more efficiently and in an eco-friendly manner.Based on digital technology,a source reduction method was designed for sulfur and fluoride control during the whole aluminum electrolysis process.New desulfurization technologies were developed for catalytic reduction of the sulfur content in petroleum coke at low temperature and catalytic reduction of SO_(2)to elemental sulfur.This work has established the technology for coupling multi-pollutant control and resource recovery from the flue gas from non-ferrous metallurgy,which provides the scientific theoretical basis and application technology for the treatment of air pollutants in the non-ferrous metallurgy industry.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
The effect of different decomposition conditions on tungsten recovery forscheelite concentrate has been examined. The results show that tungsten recovery can be more than98% under decomposing conditions as follows: th...The effect of different decomposition conditions on tungsten recovery forscheelite concentrate has been examined. The results show that tungsten recovery can be more than98% under decomposing conditions as follows: the amount of caustic soda is 2.2 and 3.2 times oftheoretical respectively, ratio of water and ore is 0.7-0.8, temperature is 160℃, and preservationtime is 2.0 h for scheelite concentrate (63.21 % WO_3) and low grade scheelite concentrate (55.17%WO_3).展开更多
Oxidation of sulfite and competitive absorption existed in Na_(2)SO_(3) solution for simultaneous removal of NO_(x) and SO_(2),inhibited the long-term high-efficiency when used for practical applications.A matching st...Oxidation of sulfite and competitive absorption existed in Na_(2)SO_(3) solution for simultaneous removal of NO_(x) and SO_(2),inhibited the long-term high-efficiency when used for practical applications.A matching strategy was developed to solve these problems.Antioxidants combination was used to retard the oxidation of antioxidant and enhance inhibition of S(IV)(tetravalent sulfur)oxidation.Hydroquinone(HQ)and sodium thiosulfate(ST)showed a positive synergistic effect on inhibition of S(IV)oxidation.When SO_(2) concentration was 500 and 2000 ppmV,the addition of 0.1 wt.%HQ and 1 wt.%ST decreased the percentage of S(IV)oxidized by oxygen by over 30%and 40%,respectively.Alkali(Na_(2)CO_(3))alleviated the competitive absorption between NO_(x) and SO_(2).Moreover,Na_(2)CO_(3) exhibited an enhancement effect on the absorption of NO_(x) and SO_(2) when coupled with anti-oxidants.While the increase of oxygen pressure accelerated the oxidation of S(IV),the anti-oxidants can retard the oxidation.The measurement of pH suggested the removal efficiency of NO_(x) highly depended on SO_(3)^(2-) concentration rather than pH.The further investigation of the mechanism suggested the match effect was related to the interaction between ST and the intermediate product of HQ.The match strategy holds a potential for application of SO_(3)^(2-) to denitration.展开更多
The application of the technique of removing molybdenum by moving packed bedand fluidized bed ion-exchange in a factory was described. The data showed that the Mo removalefficiency is above 99 percent, and the Mo cont...The application of the technique of removing molybdenum by moving packed bedand fluidized bed ion-exchange in a factory was described. The data showed that the Mo removalefficiency is above 99 percent, and the Mo content in APT (Ammonium Paratungstate) is controlledsteadily below 18 X l0^(-6), in the case of treating the feed liquor containing Mo 1.4 g/L. Thetechnique is simple and convenient in operation, good reusability of resin, loss consumption ofdesorption reagent and little pollution on environment. The loss of tungsten is less than 0.5percent. The technique bas been proved to be an economical and efficient process for Mo removal.展开更多
The mechanical properties of calcium(Ca) microalloyed 24 carat gold(Au 99.9 Ca 0.1) were measured and the corresponding microstructure was observed by TEM in order to investigate the strengthening mechanism.It was obs...The mechanical properties of calcium(Ca) microalloyed 24 carat gold(Au 99.9 Ca 0.1) were measured and the corresponding microstructure was observed by TEM in order to investigate the strengthening mechanism.It was observed that the microalloying of 0.1wt% Ca improved the tensile strength(by 79% and 57% for the rolling and annealing states,respectively),hardness and E-Modulus as well as reduced the ductility of the 24 carat Au.Dispersed nano-sized precipitates and high density deformation twins were found in the rolled Au 99.9 Ca 0.1,which are attributed to be the major strengthening factors.The twins subsided after annealing and the strengthening of the annealed Au 99.9 Ca 0.1 is mainly contributed by the coarsened semi-coherent precipitates.展开更多
The effect of barium on the refinement of primary aluminum and on themodification of eutectics in a hypoeutectic aluminum-silicon alloy was investigated. The resultsindicate that barium not only modifies the eutectic ...The effect of barium on the refinement of primary aluminum and on themodification of eutectics in a hypoeutectic aluminum-silicon alloy was investigated. The resultsindicate that barium not only modifies the eutectic silicon but also refines the primary aluminumand there is a relationship between the retained barium and the second spacing of primary aluminum.Experiments of barium-treated commercial Al-Si hypoeutectic alloy show that barium is a bettermodifier than sodium when there is a longer holding time.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
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.
基金Supported by the National Natural Science Foundation of China(72171223,71801213,71988101)。
文摘During the COVID-19 pandemic,the international financial markets experienced severe turbulence.Under the background of“Made in China 2025”,substantial entity enterprises have a large demand for non-ferrous metals.With the enhancement of financial attributes of non-ferrous metals,it is vital to prevent financial systemic risk contagion in the non-ferrous metal markets.In this article,the ensemble empirical mode decomposition method is used to decompose the prices of eight important non-ferrous metals futures,and then the dynamic DY risk spillover index model is established from the perspectives of long-term and short-term.The risk spillover between non-ferrous metals during the COVID-19 is quantitatively analyzed from different frequency domains.The study finds that in the long run,the risk spillover relationship between non-ferrous metals remained basically stable,and the change of it after the epidemic is slight.In the short run,the risk spillover relationship has different degrees of structural changes after the outbreak of the COVID-19 pandemic.The ensemble empirical mode decomposition method can distinguish the risk spillovers in different cycles,and help to formulate policies for preventing systemic risks in the non-ferrous metal markets according to the different length of terms.
文摘Spectral analysis was a method of identifying substances, determining their chemical composition and calculating their content based on their spectral characteristics. This paper mainly discussed the application of various spectroscopic techniques, mainly including atomic absorption spectrometry (AAS) inductively coupled plasma emission spectrometry (ICP-AES) X-ray fluorescence spectroscopy (XRF) atomic fluorescence spectroscopy (AFS) direct reading spectroscopy (OES) glow discharge emission spectroscopy (GD-OSE) laser-induced breakdown spectroscopy (LIBS), in the formulation of non-ferrous metal standards in China. The AAS method was the most widely used single-element microanalysis method among the non-ferrous metal standards. The ICP-AES method was good at significant advantages in the simultaneous detection of multiple elements. The XRF method was increasingly used in the determination of primary and secondary trace elements due to its simple sample preparation and high efficiency. The AFS was mostly detected by single-element trace analysis. OES GD-OES and LIBS were playing an increasingly important role in the new demand area for non-ferrous metals. This paper discussed matrix elimination, sample digestion, sample preparation, instrument categories and other aspects of some standards, and summarized the advantages of spectral analysis and traditional chemical analysis methods. The new methods of future spectroscopic technology had been illustrated in the process of developing non-ferrous metal standards.
文摘The bottom ashes resulted annually from the incineration of municipal solid waste in Europe contain about 400,000 tonnes of metallic aluminium and 200,000 tonnes of heavy non-ferrous metals, such as copper and zinc. Efficient recovery of this non-ferrous metal resource requires state-of-the-art separation technologies and a continuous feedback of laboratory analyses of the metal products and the depleted bottom ash to the operators of the bottom ash treatment plants. A methodology is presented for the optimization of the production of non-ferrous metal value from Municipal Solid Waste Incinerator bottom ash. Results for an incineration plant in the Netherlands show that efficient recycling can have a significant impact on value recovery as well as on non-ferrous metal recycling rates, producing up to 8% more revenue and 25% more metals from the ash.
基金supported by the National Natural Science Foundation of China(Nos.81800393,82170437,and 41877297)the Outstanding Young Investigator of Hunan province(No.2020JJ2056)+3 种基金the Hunan Youth Talent Project(No.2019RS2014)the Key Research and Development Project of Hunan(No.2020WK2010)the National Key Research and Development Program(No.2018YFC1311300)the Investigation and Evaluation of Groundwater Pollution in Key Areas of Central and South China by China Geological Survey(No.12120114029601).
文摘Cadmium(Cd)has received widespread attention owing to its persistent toxicity and non-degradability.Cd in the human body is mainly absorbed from the external environment and is usually assessed using urinary Cd.Hunan Province is the heartland of the Chinese non-ferrous mining area,where several serious Cd pollution events have occurred,including high levels of Cd in the urine of residents.However,the environmental factors influencing high urinary Cd levels(UCLs)in nearby residents remain unclear.Therefore,211 nearby residents’UCLs and the corresponding sociological characteristics from nine groundwater samples in this area were analyzed using statistical analysis models.Groundwater Cd concentration ranged from 0.02 to 1.15μg/L,aligning with class III of the national standard;the range of UCL of nearby residents was 0.37–36.60μg/L,exceeding the national guideline of 0–2.5μg/L.Groundwater Cd levels were positively correlated with the UCL(P<0.001,correlation coefficient 95%CI=9.68,R^(2)=0.06).In addition,sociological characteristics,such as smoking status and education level,also affect UCL.All results indicate that local governments should strengthen the prevention and abatement of groundwater Cd pollution.This study is the first to systematically evaluate the relationship between groundwater Cd and UCL using internal and external environmental exposure data.These findings provide essential bases for relevant departments to reduce Cd exposure in regions where the heavy metal industry is globally prevalent.
文摘This study reports on the impact of the curing conditions on the mechanical properties and leaching of inorganic polymer （IP） mortars made from a water quenched fayalitic slag. Three similar IP mortars were produced by mixing together slag, aggregate and activating solution, and cured in three different environments for 28 d： a） at 20℃ and relative humidity （RH） - 50% （T20RH50）, b） at 20℃and RH≥90% （T20RH90） and c） at 60℃ and RH - 20% （T60RH20）. Compressive strength （EN 196-1） varied between 19 MPa （T20RH50） and 31 MPa （T20RH90）. This was found to be attributed to the cracks formed upon curing. Geochemical modelling and two leaching tests were performed, the EA NEN 7375 tank test, and the BS EN 12457-1 single batch test. Results show that Cu, Ni, Pb, Zn andAs leaching occurred even at high pH, which varied between 10 and 11 in the tank test＇s leachates and between 12 and 12.5 in the single batch＇s leachates. Leaching values obtained were below the requirements for non-shaped materials of Flemish legislation for As, Cu and Ni in the single batch test.
基金supported by the National Natural Science Foundation of China(No.52234011)the National Key R&D Program of China(No.2017YFC0210400)。
文摘Air pollutant emissions represent a critical challenge in the green development of the non-ferrous metallurgy industry.This work studied the emission characteristics,formation mechanisms,phase transformation and separation of typical air pollutants,such as heavy metal particles,mercury,sulfur oxides and fluoride,during non-ferrous smelting.A series of purification technologies,including optimization of the furnace throat and hightemperature discharge,were developed to collaboratively control and recover fine particles from the flue gas of heavy metal smelting processes,including copper,lead and zinc.Significant improvements have been realized in wet scrubbing technology for removing mercury,fluoride and SO_(2)from flue gas.Gas-liquid sulfidation technology by applying H_(2)S was invented to recycle the acid scrubbing wastewater more efficiently and in an eco-friendly manner.Based on digital technology,a source reduction method was designed for sulfur and fluoride control during the whole aluminum electrolysis process.New desulfurization technologies were developed for catalytic reduction of the sulfur content in petroleum coke at low temperature and catalytic reduction of SO_(2)to elemental sulfur.This work has established the technology for coupling multi-pollutant control and resource recovery from the flue gas from non-ferrous metallurgy,which provides the scientific theoretical basis and application technology for the treatment of air pollutants in the non-ferrous metallurgy industry.
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.
文摘The effect of different decomposition conditions on tungsten recovery forscheelite concentrate has been examined. The results show that tungsten recovery can be more than98% under decomposing conditions as follows: the amount of caustic soda is 2.2 and 3.2 times oftheoretical respectively, ratio of water and ore is 0.7-0.8, temperature is 160℃, and preservationtime is 2.0 h for scheelite concentrate (63.21 % WO_3) and low grade scheelite concentrate (55.17%WO_3).
基金financially supported by the National Key R and D Program of China(No.2018YFC0213400)the National Natural Science Foundation of China(No.21976118)supported by the Startup Fund for Youngman Research at SJTU(No.19X100040083)。
文摘Oxidation of sulfite and competitive absorption existed in Na_(2)SO_(3) solution for simultaneous removal of NO_(x) and SO_(2),inhibited the long-term high-efficiency when used for practical applications.A matching strategy was developed to solve these problems.Antioxidants combination was used to retard the oxidation of antioxidant and enhance inhibition of S(IV)(tetravalent sulfur)oxidation.Hydroquinone(HQ)and sodium thiosulfate(ST)showed a positive synergistic effect on inhibition of S(IV)oxidation.When SO_(2) concentration was 500 and 2000 ppmV,the addition of 0.1 wt.%HQ and 1 wt.%ST decreased the percentage of S(IV)oxidized by oxygen by over 30%and 40%,respectively.Alkali(Na_(2)CO_(3))alleviated the competitive absorption between NO_(x) and SO_(2).Moreover,Na_(2)CO_(3) exhibited an enhancement effect on the absorption of NO_(x) and SO_(2) when coupled with anti-oxidants.While the increase of oxygen pressure accelerated the oxidation of S(IV),the anti-oxidants can retard the oxidation.The measurement of pH suggested the removal efficiency of NO_(x) highly depended on SO_(3)^(2-) concentration rather than pH.The further investigation of the mechanism suggested the match effect was related to the interaction between ST and the intermediate product of HQ.The match strategy holds a potential for application of SO_(3)^(2-) to denitration.
文摘The application of the technique of removing molybdenum by moving packed bedand fluidized bed ion-exchange in a factory was described. The data showed that the Mo removalefficiency is above 99 percent, and the Mo content in APT (Ammonium Paratungstate) is controlledsteadily below 18 X l0^(-6), in the case of treating the feed liquor containing Mo 1.4 g/L. Thetechnique is simple and convenient in operation, good reusability of resin, loss consumption ofdesorption reagent and little pollution on environment. The loss of tungsten is less than 0.5percent. The technique bas been proved to be an economical and efficient process for Mo removal.
基金carried out with the partial financial support of Lao Feng xiang Co.Ltd.
文摘The mechanical properties of calcium(Ca) microalloyed 24 carat gold(Au 99.9 Ca 0.1) were measured and the corresponding microstructure was observed by TEM in order to investigate the strengthening mechanism.It was observed that the microalloying of 0.1wt% Ca improved the tensile strength(by 79% and 57% for the rolling and annealing states,respectively),hardness and E-Modulus as well as reduced the ductility of the 24 carat Au.Dispersed nano-sized precipitates and high density deformation twins were found in the rolled Au 99.9 Ca 0.1,which are attributed to be the major strengthening factors.The twins subsided after annealing and the strengthening of the annealed Au 99.9 Ca 0.1 is mainly contributed by the coarsened semi-coherent precipitates.
基金This work is financially supported by the National Natural Science Foundation of China (No. 59631080)
文摘The effect of barium on the refinement of primary aluminum and on themodification of eutectics in a hypoeutectic aluminum-silicon alloy was investigated. The resultsindicate that barium not only modifies the eutectic silicon but also refines the primary aluminumand there is a relationship between the retained barium and the second spacing of primary aluminum.Experiments of barium-treated commercial Al-Si hypoeutectic alloy show that barium is a bettermodifier than sodium when there is a longer holding time.
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.
