The solid structures and thermostabilities of Cu-Fe-O and Cu-Fe-Ce-O supported on alumina were studied by XRD, ESR, Mossbauer and TPR techniques. The studies indicate that there are Fe2CuO4, CuO and alpha-Fe2O3 phases...The solid structures and thermostabilities of Cu-Fe-O and Cu-Fe-Ce-O supported on alumina were studied by XRD, ESR, Mossbauer and TPR techniques. The studies indicate that there are Fe2CuO4, CuO and alpha-Fe2O3 phases in Cu-Fe-O with the granula of less than 13 nm. With the catalyst pretreatment temperature rising, the crystallite of Fe2CuO4 in the catalysts grows up and that of CuO disappears gradually. The presence of Ce leads to the increase of Cu2+ concentration, inhibits the crystal growth of CuO and Fe2CuO4 in the catalyst except that of Fe2O3, and eliminates the difference for reductive reaction of oxygen in Fe-O and Cu-O. At 800 degrees C, the crystal growth of Fe2O3 in Cu-Fe-Ce-O is slower than that in Cu-Fe-O, i.e., CeO2 in Cu-Fe-Ce-O inhibits the growth of Fe2O3 phase effectively, and enhances the thermostability of catalysts so as to avoid the sintering of active elements in catalysts. CeO2 promotes the reducibility of catalysts at lower temperature.展开更多
Several researches have been reported about the characteristic of β-Ga_2O_3 nanowires which was synthesized on nickel oxide particle.But indeed,recent researches about synthesis of β-Ga_2O_3 nanowires on oxide-assis...Several researches have been reported about the characteristic of β-Ga_2O_3 nanowires which was synthesized on nickel oxide particle.But indeed,recent researches about synthesis of β-Ga_2O_3 nanowires on oxide-assisted transition metal are limited to nickel or cobalt oxide catalyst.In this work,Gallium oxide(β-Ga_2O_3)nanowires were synthesized by a simple thermal evaporation method from gallium powder in the range of 700-1000℃ using the iron,nickel,copper,cobalt and zinc oxide as a catalyst,respectively.The β-Ga_2O_3 nanowires with single crystalline without defects were successfully synthesized at the reaction temperature of 850,900 and 950℃ in all the catalysts.But optimum experimental condition in synthesis of nanowires varied with the kind of catalyst.As increasing synthesis temperature,the morphology of gallium oxide nanowires changed from nanowires to nanorods,and its diameter increased.From these results,we could be proposed that the growth mechanism of β-Ga_2O_3 nanowires was changed with synthesis temperature of nanowires.Microstructure and morphology of Synthesized nanowire was characterized by HR-TEM,FE-SEM,EDX and XRD.展开更多
Objective:To determine the effects of routine iron supplementation on oxidative stress markers in pregnant women.Methods:This study enrolled 122 pregnant women aged between 20-38 years throughout three stages of pregn...Objective:To determine the effects of routine iron supplementation on oxidative stress markers in pregnant women.Methods:This study enrolled 122 pregnant women aged between 20-38 years throughout three stages of pregnancy:beginning with pregnancy,until the twentieth week and up to the thirtieth week.They were divided into two groups:61 pregnant women not supplemented with iron(the control group),and 61 pregnant women supplemented with iron(the iron group).Blood samples were collected and protein,iron,uric acid,total bilirubin level and oxidative stress status were estimated using molecular spectrophotometric method.Copper levels were estimated by using atomic absorption spectroscopy method.Results:Iron,protein and copper concentrations were significantly increased(P<0.05)at 20 and 30 weeks of pregnancy and hemoglobin level was significantly increased(P<0.05)at the beginning of pregnancy and until 20 weeks in the iron group compared to the control group.In addition,levels of serum uric acid,serum total bilirubin and malondialdehyde in serum and erythrocytes were significantly increased at 20 and 30 weeks of pregnancy whereas the reduced glutathione level was significantly decreased in serum(30 weeks of pregnancy)and erythrocytes(20 and 30 weeks of pregnancy)in the iron group as compared to the control group.Serum oxygen radical absorbance capacity was not significantly changed.There was a significant positive correlation between serum iron level and serum copper,malondialdehyde level in serum and erythrocytes in pregnant women supplemented with iron.Conclusions:Iron supplement at 20 and 30 weeks of pregnancy plays a role in the development of oxidative stress which is the origin of several maternal-fetal complications.展开更多
To recover metal from copper slags,a new process involving two steps of oxidative desulfurization followed by smelting reduction was proposed in which one hazardous waste(waste cathode carbon)was used to treat another...To recover metal from copper slags,a new process involving two steps of oxidative desulfurization followed by smelting reduction was proposed in which one hazardous waste(waste cathode carbon)was used to treat another(copper slags).The waste cathode carbon is used not only as a reducing agent but also as a fluxing agent to decrease slag melting point.Upon holding for 60 min in air atmosphere first and then smelting with 14.4 wt%waste cathode carbon and 25 wt%CaO for 180 min in high purity Ar atmosphere at 1450℃,the recovery rates of Cu and Fe reach 95.89%and 94.64%,respectively,and meanwhile greater than 90%of the fluoride from waste cathode carbon is transferred into the final slag as CaF_(2) and Ca_(2)Si_(2)F_(2)O_(7),which makes the content of soluble F in the slag meet the national emission standard.Besides,the sulphur content in the obtained Fe-Cu alloy is low to 0.03 wt%.展开更多
A microreactor system was used to study the catalytic reaction of NO+CO→1/2 N_2+CO_2 over Cu,Fe, Mn,Cr,and Ce oxides supported on alumina,and the effect of adding Ce in supported Cu-M-O(M=Mn,Fe and Cr) catalysts on t...A microreactor system was used to study the catalytic reaction of NO+CO→1/2 N_2+CO_2 over Cu,Fe, Mn,Cr,and Ce oxides supported on alumina,and the effect of adding Ce in supported Cu-M-O(M=Mn,Fe and Cr) catalysts on their catalytic activities for the topic reaction and the concentration of N_2O produced.It was found that the catalytic activity order of the single-element oxide is:CuO>Fe_2O_3≈Cr_2O_3> MnO_2>CeO_2>NiO.Cu-Mn-O is more active than CuO,and Cu-Fe-O is more active than Cu-Mn-O and Cu-Cr-O for NO+CO reaction.This study shows that the addition of Ce in supported Cu-M-O can promote their catalytic activities Jot the topic reaction,which makes the reaction of 2NO+CO→N_2O+CO_2 fast,and N_2O is an intermediate compound produced during NO+CO reaction.展开更多
The Lala Cu deposit in Sichuan Province is one of the most important large deposits in SW China,both in terms of Cu and associated Au-Mo-Co-REE-Fe. Systematic ore petrology study shows that ore minerals are mainly com...The Lala Cu deposit in Sichuan Province is one of the most important large deposits in SW China,both in terms of Cu and associated Au-Mo-Co-REE-Fe. Systematic ore petrology study shows that ore minerals are mainly composed of hydrothermal magnetite,chalcopyrite and molybdenite.The wall-rock alterations include biotitization,silicification, carbonatation,albitization,potash feldspathization, apatitation,actinolitation and fluoritation,et al. The Pyrite and magnetite have euhedral-subhedral crystalline grained texture and the chalcopyrite展开更多
It is quite evident that it is not anomalous metal transport,nor unique depositional conditions,nor any single factor at the deposit scale,that dictates whether a mineral deposit becomes a giant or not.A hierarchical ...It is quite evident that it is not anomalous metal transport,nor unique depositional conditions,nor any single factor at the deposit scale,that dictates whether a mineral deposit becomes a giant or not.A hierarchical approach thus is required to progressively examine controlling parameters at successively decreasing scales in the total mineral system to understand the location of giant gold deposits in non-arc environments.For giant orogenic,intrusion-related gold systems(IRGS) and Carlin-type gold deposits and iron oxide-copper-gold(IOCG) deposits,there are common factors among all of these at the lithospheric to crustal scale.All are sited in giant gold provinces controlled by complex fundamental fault or shear zones that follow craton margins or,in the case of most Phanerozoic orogenic giants,define the primary suture zones between tectonic terranes.Giant provinces of IRGS,IOCG,and Carlin-type deposits require melting of metasomatized lithosphere beneath craton margins with ascent of hybrid lamprophyric to granitic magmas and associated heat flux to generate the giant province.The IRGS and IOCG deposits require direct exsolution of volatile-rich magmatic-hydrothermal fluids,whereas the association of such melts with Carlin-type ores is more indirect and enigmatic.Giant orogenic gold provinces show no direct relationship to such magmatism.forming from metamorphic fluids,but show an indirect relationship to lamprophyres that reflect the mantle connectivity of controlling first-order structures.In contrast to their province scale similarities,the different giant gold deposit styles show contrasting critical controls at the district to deposit scale.For orogenic gold deposits,the giants appear to have formed by conjunction of a greater number of parameters to those that control smaller deposits,with resultant geometrical and lithostratigraphic complexity as a guide to their location.There are few giant IRGS due to their inferior fluid-flux systems relative to orogenic gold deposits,and those few giants are essentially preservational exceptions.Many Carlin-type deposits are giants due to the exceptional conjunction of both structural and lithological parameters that caused reactive and permeable rocks,enriched in syngenetic gold,to be located below an impermeable cap along antiformal "trends".Hydrocarbons probably played an important role in concentrating metal.The supergiant Post-Betze deposit has additional ore zones in strain heterogeneities surrounding the pre-gold Goldstrike stock.All unequivocal IOCG deposits are giant or near-giant deposits in terms of gold-equivalent resources,partly due to economic factors for this relatively poorly understood,low Cu-Au grade deposit type.The supergiant Olympic Dam deposit,the most shallowly formed deposit among the larger IOCGs,probably owes its origin to eruption of volatile-rich hybrid magma at surface,with formation of a large maar and intense and widespread brecciation,alteration and Cu-Au-U deposition in a huge rock volume.展开更多
This paper reports a simple and efficient chemical method to decorate multi-walled carbon nano- tubes(MWCNTs) with iron oxide nanoparticles. The TEM, FTIR, Raman and UV analysis demonstrate that iron oxide nanoparti...This paper reports a simple and efficient chemical method to decorate multi-walled carbon nano- tubes(MWCNTs) with iron oxide nanoparticles. The TEM, FTIR, Raman and UV analysis demonstrate that iron oxide nanoparticles were well deposited on the outer walls of MWCNTs. The size of the nanoparticles ranges from 30 to 50 nm. The sorption property of MWCNTs/Fe3O4 composites for the removal of 2,4-dichlorophenol(2,4-DCP) and Cu2+ ions from aqueous solution was explored. The results present that MWCNTs decorated with Fe3O4 possessed higher sorption capability for removing 2,4-DCP and Cu2+ ions, which favour the highly potential applications for pollutants removal from water.展开更多
The organic compounds contaminated soil substantially threatens the growth of plants and food safety.In this study,we synthesis zero-valent bimetallic Fe/Cu catalysts for the degradation of 2,4-dichlorophenol(DCP)in s...The organic compounds contaminated soil substantially threatens the growth of plants and food safety.In this study,we synthesis zero-valent bimetallic Fe/Cu catalysts for the degradation of 2,4-dichlorophenol(DCP)in soils with persulfate(PS)in combination of organic surfactants and exploring the main environmental impact factors.The kinetic experiments show that the 5%(mass)dosage of Fe/Cu exhibits a higher degradation efficiency(86%)of DCP in soils,and the degradation efficiency of DCP increases with the increase of the initial PS concentration.Acidic conditions are favorable for the DCP degradation in soils.More importantly,the addition of Tween-80,and Triton-100 can obviously desorb DCP from the soil surface,which enhances the degradation efficiency of DCP in soils by Fe/Cu and PS reaction system.Furthermore,the Quenching experiments demonstrate that SO_(4)^(-1)·and·OH are the predominant radicals for the degradation of DCP during the Fe/Cu and PS reaction system as well as non-radical also exist.The findings of this work provide an effective method for remediating DCP from soils.展开更多
The aim of the present study was to investigate the status of oxidative stress in the serum of patients affected with cancer breast. Changes in the levels of total antioxidant capacity (TAC), uric acid, malondialdehyd...The aim of the present study was to investigate the status of oxidative stress in the serum of patients affected with cancer breast. Changes in the levels of total antioxidant capacity (TAC), uric acid, malondialdehyde (MDA), nitric oxide (nitrite/nitrate), cupper and iron were measured in serum of patients affected by non-metastatic as well as metastatic cancer breast. Significant decrease in TAC (32.7-37.5%), uric acid (28.1%-49.2), MDA (20.7%-25.2%) and nitric oxide (50.4%-61.9) were found in both groups of cancer breast patients compared to the control group. Serum Cu++ concentrations were significantly lower in metastatic cancer patient group compared with both control and non-metastatic cancer groups. Fe++ in serum was significantly lower in patients with non-metastatic cancer compared to normal subjects and patients with metastatic cancer. Significant differences were also observed between patients with non-metastatic and metastatic cancer breast as regards serum uric acid, nitric oxide were higher were observed in non-metastatic compared with metastatic cancer breast.展开更多
文摘The solid structures and thermostabilities of Cu-Fe-O and Cu-Fe-Ce-O supported on alumina were studied by XRD, ESR, Mossbauer and TPR techniques. The studies indicate that there are Fe2CuO4, CuO and alpha-Fe2O3 phases in Cu-Fe-O with the granula of less than 13 nm. With the catalyst pretreatment temperature rising, the crystallite of Fe2CuO4 in the catalysts grows up and that of CuO disappears gradually. The presence of Ce leads to the increase of Cu2+ concentration, inhibits the crystal growth of CuO and Fe2CuO4 in the catalyst except that of Fe2O3, and eliminates the difference for reductive reaction of oxygen in Fe-O and Cu-O. At 800 degrees C, the crystal growth of Fe2O3 in Cu-Fe-Ce-O is slower than that in Cu-Fe-O, i.e., CeO2 in Cu-Fe-Ce-O inhibits the growth of Fe2O3 phase effectively, and enhances the thermostability of catalysts so as to avoid the sintering of active elements in catalysts. CeO2 promotes the reducibility of catalysts at lower temperature.
文摘Several researches have been reported about the characteristic of β-Ga_2O_3 nanowires which was synthesized on nickel oxide particle.But indeed,recent researches about synthesis of β-Ga_2O_3 nanowires on oxide-assisted transition metal are limited to nickel or cobalt oxide catalyst.In this work,Gallium oxide(β-Ga_2O_3)nanowires were synthesized by a simple thermal evaporation method from gallium powder in the range of 700-1000℃ using the iron,nickel,copper,cobalt and zinc oxide as a catalyst,respectively.The β-Ga_2O_3 nanowires with single crystalline without defects were successfully synthesized at the reaction temperature of 850,900 and 950℃ in all the catalysts.But optimum experimental condition in synthesis of nanowires varied with the kind of catalyst.As increasing synthesis temperature,the morphology of gallium oxide nanowires changed from nanowires to nanorods,and its diameter increased.From these results,we could be proposed that the growth mechanism of β-Ga_2O_3 nanowires was changed with synthesis temperature of nanowires.Microstructure and morphology of Synthesized nanowire was characterized by HR-TEM,FE-SEM,EDX and XRD.
基金the research project funded by the ministry of higher education,Algeria and by Directorate general for Scientific Research and Technological Development(Grant D01N01UN390120190001).
文摘Objective:To determine the effects of routine iron supplementation on oxidative stress markers in pregnant women.Methods:This study enrolled 122 pregnant women aged between 20-38 years throughout three stages of pregnancy:beginning with pregnancy,until the twentieth week and up to the thirtieth week.They were divided into two groups:61 pregnant women not supplemented with iron(the control group),and 61 pregnant women supplemented with iron(the iron group).Blood samples were collected and protein,iron,uric acid,total bilirubin level and oxidative stress status were estimated using molecular spectrophotometric method.Copper levels were estimated by using atomic absorption spectroscopy method.Results:Iron,protein and copper concentrations were significantly increased(P<0.05)at 20 and 30 weeks of pregnancy and hemoglobin level was significantly increased(P<0.05)at the beginning of pregnancy and until 20 weeks in the iron group compared to the control group.In addition,levels of serum uric acid,serum total bilirubin and malondialdehyde in serum and erythrocytes were significantly increased at 20 and 30 weeks of pregnancy whereas the reduced glutathione level was significantly decreased in serum(30 weeks of pregnancy)and erythrocytes(20 and 30 weeks of pregnancy)in the iron group as compared to the control group.Serum oxygen radical absorbance capacity was not significantly changed.There was a significant positive correlation between serum iron level and serum copper,malondialdehyde level in serum and erythrocytes in pregnant women supplemented with iron.Conclusions:Iron supplement at 20 and 30 weeks of pregnancy plays a role in the development of oxidative stress which is the origin of several maternal-fetal complications.
基金Project(U1602272)supported by the National Natural Science Foundation of China。
文摘To recover metal from copper slags,a new process involving two steps of oxidative desulfurization followed by smelting reduction was proposed in which one hazardous waste(waste cathode carbon)was used to treat another(copper slags).The waste cathode carbon is used not only as a reducing agent but also as a fluxing agent to decrease slag melting point.Upon holding for 60 min in air atmosphere first and then smelting with 14.4 wt%waste cathode carbon and 25 wt%CaO for 180 min in high purity Ar atmosphere at 1450℃,the recovery rates of Cu and Fe reach 95.89%and 94.64%,respectively,and meanwhile greater than 90%of the fluoride from waste cathode carbon is transferred into the final slag as CaF_(2) and Ca_(2)Si_(2)F_(2)O_(7),which makes the content of soluble F in the slag meet the national emission standard.Besides,the sulphur content in the obtained Fe-Cu alloy is low to 0.03 wt%.
文摘A microreactor system was used to study the catalytic reaction of NO+CO→1/2 N_2+CO_2 over Cu,Fe, Mn,Cr,and Ce oxides supported on alumina,and the effect of adding Ce in supported Cu-M-O(M=Mn,Fe and Cr) catalysts on their catalytic activities for the topic reaction and the concentration of N_2O produced.It was found that the catalytic activity order of the single-element oxide is:CuO>Fe_2O_3≈Cr_2O_3> MnO_2>CeO_2>NiO.Cu-Mn-O is more active than CuO,and Cu-Fe-O is more active than Cu-Mn-O and Cu-Cr-O for NO+CO reaction.This study shows that the addition of Ce in supported Cu-M-O can promote their catalytic activities Jot the topic reaction,which makes the reaction of 2NO+CO→N_2O+CO_2 fast,and N_2O is an intermediate compound produced during NO+CO reaction.
文摘The Lala Cu deposit in Sichuan Province is one of the most important large deposits in SW China,both in terms of Cu and associated Au-Mo-Co-REE-Fe. Systematic ore petrology study shows that ore minerals are mainly composed of hydrothermal magnetite,chalcopyrite and molybdenite.The wall-rock alterations include biotitization,silicification, carbonatation,albitization,potash feldspathization, apatitation,actinolitation and fluoritation,et al. The Pyrite and magnetite have euhedral-subhedral crystalline grained texture and the chalcopyrite
基金funded by Talent Award under the 1000 Plan Project from the Chinese Government
文摘It is quite evident that it is not anomalous metal transport,nor unique depositional conditions,nor any single factor at the deposit scale,that dictates whether a mineral deposit becomes a giant or not.A hierarchical approach thus is required to progressively examine controlling parameters at successively decreasing scales in the total mineral system to understand the location of giant gold deposits in non-arc environments.For giant orogenic,intrusion-related gold systems(IRGS) and Carlin-type gold deposits and iron oxide-copper-gold(IOCG) deposits,there are common factors among all of these at the lithospheric to crustal scale.All are sited in giant gold provinces controlled by complex fundamental fault or shear zones that follow craton margins or,in the case of most Phanerozoic orogenic giants,define the primary suture zones between tectonic terranes.Giant provinces of IRGS,IOCG,and Carlin-type deposits require melting of metasomatized lithosphere beneath craton margins with ascent of hybrid lamprophyric to granitic magmas and associated heat flux to generate the giant province.The IRGS and IOCG deposits require direct exsolution of volatile-rich magmatic-hydrothermal fluids,whereas the association of such melts with Carlin-type ores is more indirect and enigmatic.Giant orogenic gold provinces show no direct relationship to such magmatism.forming from metamorphic fluids,but show an indirect relationship to lamprophyres that reflect the mantle connectivity of controlling first-order structures.In contrast to their province scale similarities,the different giant gold deposit styles show contrasting critical controls at the district to deposit scale.For orogenic gold deposits,the giants appear to have formed by conjunction of a greater number of parameters to those that control smaller deposits,with resultant geometrical and lithostratigraphic complexity as a guide to their location.There are few giant IRGS due to their inferior fluid-flux systems relative to orogenic gold deposits,and those few giants are essentially preservational exceptions.Many Carlin-type deposits are giants due to the exceptional conjunction of both structural and lithological parameters that caused reactive and permeable rocks,enriched in syngenetic gold,to be located below an impermeable cap along antiformal "trends".Hydrocarbons probably played an important role in concentrating metal.The supergiant Post-Betze deposit has additional ore zones in strain heterogeneities surrounding the pre-gold Goldstrike stock.All unequivocal IOCG deposits are giant or near-giant deposits in terms of gold-equivalent resources,partly due to economic factors for this relatively poorly understood,low Cu-Au grade deposit type.The supergiant Olympic Dam deposit,the most shallowly formed deposit among the larger IOCGs,probably owes its origin to eruption of volatile-rich hybrid magma at surface,with formation of a large maar and intense and widespread brecciation,alteration and Cu-Au-U deposition in a huge rock volume.
基金Supported by the National Natural Science Foundation of China(No.50878061)the National High Technology Research and Development Program of China(No.2007AA06Z303)+1 种基金State Key Lab of Urban Water Resource and Environment Fund (No.ESK200801)Scientific Research Foundation of Harbin City,China(No.2007RFXXS022)
文摘This paper reports a simple and efficient chemical method to decorate multi-walled carbon nano- tubes(MWCNTs) with iron oxide nanoparticles. The TEM, FTIR, Raman and UV analysis demonstrate that iron oxide nanoparticles were well deposited on the outer walls of MWCNTs. The size of the nanoparticles ranges from 30 to 50 nm. The sorption property of MWCNTs/Fe3O4 composites for the removal of 2,4-dichlorophenol(2,4-DCP) and Cu2+ ions from aqueous solution was explored. The results present that MWCNTs decorated with Fe3O4 possessed higher sorption capability for removing 2,4-DCP and Cu2+ ions, which favour the highly potential applications for pollutants removal from water.
基金financially supported by the National Natural Science Foundation of China(2187616141420104007)+3 种基金the National Key Research and Development Project of China(No.2018YFF0213403)Guangdong Academy of Sciences’Project(2019GDASYL-01020062019GDASYL-03010022018GDASCX-0501)。
文摘The organic compounds contaminated soil substantially threatens the growth of plants and food safety.In this study,we synthesis zero-valent bimetallic Fe/Cu catalysts for the degradation of 2,4-dichlorophenol(DCP)in soils with persulfate(PS)in combination of organic surfactants and exploring the main environmental impact factors.The kinetic experiments show that the 5%(mass)dosage of Fe/Cu exhibits a higher degradation efficiency(86%)of DCP in soils,and the degradation efficiency of DCP increases with the increase of the initial PS concentration.Acidic conditions are favorable for the DCP degradation in soils.More importantly,the addition of Tween-80,and Triton-100 can obviously desorb DCP from the soil surface,which enhances the degradation efficiency of DCP in soils by Fe/Cu and PS reaction system.Furthermore,the Quenching experiments demonstrate that SO_(4)^(-1)·and·OH are the predominant radicals for the degradation of DCP during the Fe/Cu and PS reaction system as well as non-radical also exist.The findings of this work provide an effective method for remediating DCP from soils.
文摘The aim of the present study was to investigate the status of oxidative stress in the serum of patients affected with cancer breast. Changes in the levels of total antioxidant capacity (TAC), uric acid, malondialdehyde (MDA), nitric oxide (nitrite/nitrate), cupper and iron were measured in serum of patients affected by non-metastatic as well as metastatic cancer breast. Significant decrease in TAC (32.7-37.5%), uric acid (28.1%-49.2), MDA (20.7%-25.2%) and nitric oxide (50.4%-61.9) were found in both groups of cancer breast patients compared to the control group. Serum Cu++ concentrations were significantly lower in metastatic cancer patient group compared with both control and non-metastatic cancer groups. Fe++ in serum was significantly lower in patients with non-metastatic cancer compared to normal subjects and patients with metastatic cancer. Significant differences were also observed between patients with non-metastatic and metastatic cancer breast as regards serum uric acid, nitric oxide were higher were observed in non-metastatic compared with metastatic cancer breast.
基金financial support from industrial sponsors Aurubis AG(Germany)the Australian Research Council Linkage Program+5 种基金Boliden(Sweden)Metso Outotec Oyj(Finland)Nyrstar(Australia)Kazzinc LtdGlencore(Kazakhstan)Umicore NV(Belgium)are gratefully acknowledged。