BACKGROUND:This study aims to evaluate the eff ect of continuous renal replacement therapy(CRRT)on inflammation-related anemia,iron metabolism,and the prognosis in sepsis patients with acute kidney injury(AKI).METHODS...BACKGROUND:This study aims to evaluate the eff ect of continuous renal replacement therapy(CRRT)on inflammation-related anemia,iron metabolism,and the prognosis in sepsis patients with acute kidney injury(AKI).METHODS:Sepsis patients with AKI were prospectively enrolled and randomized into the CRRT and control groups.The clinical and laboratory data on days 1,3 and 7 after intensive care unit(ICU)admission were collected.The serum interleukin(IL)-6,hepcidin,erythropoietin,ferritin,and soluble transferrin receptor(sTfR)were determined by enzyme-linked immunosorbent assay.The Sequential Organ Failure Assessment(SOFA)score and 28-day mortality were recorded.Data were analyzed using Pearson’s Chi-square test or Fisher’s exact test(categorical variables),and Mann-Whitney U-test or t-test(continuous variables).RESULTS:The hemoglobin and serum erythropoietin levels did not signifi cantly diff er between the CRRT and control groups though gradually decreased within the first week of ICU admission.On days 3 and 7,the serum IL-6,hepcidin,ferritin,and red blood cell distribution width significantly decreased in the CRRT group compared to the control group(all P<0.05).On day 7,the serum iron was significantly elevated in the CRRT group compared to the control group(P<0.05).However,the serum sTfR did not signifi cantly diff er between the groups over time.In addition,the SOFA scores were signifi cantly lower in the CRRT group compared to the control group on day 7.The 28-day mortality did not signifi cantly diff er between the control and CRRT groups(38.0%vs.28.2%,P=0.332).CONCLUSION:CRRT might have beneficial effects on the improvement in inflammationrelated iron metabolism and disease severity during the fi rst week of ICU admission but not anemia and 28-day mortality in sepsis patients with AKI.展开更多
It is important to remove the impurities, such as copper and cadmium, from leaching solution in zinc hydrometallurgy. To improve purification efficiency, a replacement-column purification device was proposed and its m...It is important to remove the impurities, such as copper and cadmium, from leaching solution in zinc hydrometallurgy. To improve purification efficiency, a replacement-column purification device was proposed and its mass transfer characteristics and purification efficiency were experimentally studied. The results show that purification efficiency increases with the decrease of the zinc powder diameter and decreases with the increase of solution velocity. If appropriate structure and operation parameters are used, it is possible to make purification efficiency more than 99%, but the diameter of zinc powder should be larger than 0.45 mm. For the velocity of 0.05-0.7 cm/s, mass transfer coefficient kc is in the range of 3.94×10-7-2.76×10-6 m/s, and increases with the decrease of zinc powder diameter and the increase of solution velocity. Moreover, it can be derived by mass transfer correlations of Sherwood number:Sh=0.1069Re0.5Sc0.33, for 0.3<Re<6.展开更多
Currently, the majority of copper tailings are not effectively developed. Worldwide, large amounts of copper tailings generated from copper production are continuously dumped, posing a potential environmental threat. ...Currently, the majority of copper tailings are not effectively developed. Worldwide, large amounts of copper tailings generated from copper production are continuously dumped, posing a potential environmental threat. Herein, the recovery of iron from copper tailings via low-temperature direct reduction and magnetic separation was conducted; process optimization was carried out, and the corresponding mineralogy was investigated. The reduction time, reduction temperature, reducing agent (coal), calcium chloride additive, grinding time, and magnetic field intensity were examined for process optimization. Mineralogical analyses of the sample, reduced pellets, and magnetic concentrate under various conditions were performed by X-ray diffraction, optical microscopy, and scanning electron microscopy-energy-dispersive X-ray spectrometry to elucidate the iron reduction and growth mechanisms. The results indicated that the optimum parameters of iron recovery include a reduction temperature of 1150A degrees C, a reduction time of 120 min, a coal dosage of 25%, a calcium chloride dosage of 2.5%, a magnetic field intensity of 100 mT, and a grinding time of 1 min. Under these conditions, the iron grade in the magnetic concentrate was greater than 90%, with an iron recovery ratio greater than 95%.展开更多
In this paper,the combined addition of copper or iron and sulphate ions onto TiO_(2) prepared by a simple sol-gel method is studied for formic acid photocatalytic conversion.A wide structural and morphological charact...In this paper,the combined addition of copper or iron and sulphate ions onto TiO_(2) prepared by a simple sol-gel method is studied for formic acid photocatalytic conversion.A wide structural and morphological characterization of the different photocatalysts was performed by X-ray diffraction(XRD),N_(2)-physisorption for BET surface area measurements,scanning and transmission electronic microscopies(SEM and TEM),UV-Vis diffuse spectroscopy(DRS)and X-ray photoelectron spectroscopy(XPS),in order to correlate the physico-chemical properties of the materials to their photocatalytic efficiencies for formic acid oxidation.Results have shown important differences among the catalysts depending on the metal added.Sulphated TiO_(2)/Cu(1%Cu)was the best photocatalyst obtaining about 100% formic acid conversion in only 5 min.The appropriate physico-chemical features of this photocatalyst,given by the addition of combined copper and sulphate ions,explain its excellence in photocatalytic reaction.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 selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone(2-PYAINH) was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At ...A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone(2-PYAINH) was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At a pH value of 7.0, 9,0, 9.0, and 8.0, respectively, which greatly increased the selectivity; nickel, copper, cobalt, and iron reacted with 2-PYAINH to form a 1:2 yellow-orange, 1:2 yellow-green, 1:2 yellow and 1:1 yellow complexes, with absorption peaks at 363, 352, 346, and 359 nm, respectively. Under the optimal conditions, Beer's law was obeyed over the ranges of 0.01-1.4, 0.01-1.5, 0.01-2.7, and 0.01-5.4 mg/L respectively. The apparent molar absorptivity and Sandell's sensitivities were 8.4×10^4, 5.2×10^4, 7.1×10^4, and 3.9×10^4 L·mol^-l·cm^-1, respectively, and 0.00069, 0.0012, 0.00078, and 0.0014 μg·cm2, respectively. The detection limits were found to be 0.001, 0.002, 0.003, and 0.01 mg/L, respectively. The detailed study of various interfering ions to make the method more sensitive was carried out and selective and several real samples were analyzed with satisfactory results.展开更多
In the present study, pure iron/copper composite metal cladding was deposited onto carbon steel by tungsten inert gas welding. The study focused on interfacial morphological, microstructural, and mechanical analyses o...In the present study, pure iron/copper composite metal cladding was deposited onto carbon steel by tungsten inert gas welding. The study focused on interfacial morphological, microstructural, and mechanical analyses of the composite cladding layers. Iron liquid–solid-phase zones were formed at copper/steel and iron interfaces because of the melting of the steel substrate and iron. Iron concentrated in the copper cladding layer was observed to exhibit belt, globule, and dendrite morphologies. The appearance of iron-rich globules indicated the occurrence of liquid phase separation(LPS) prior to solidification, and iron-rich dendrites crystallized without the occurrence of LPS. The maximum microhardness of the iron/steel interface was lower than that of the copper/steel interface because of the diffusion of elemental carbon. All samples fractured in the cladding layers. Because of a relatively lower strength of the copper layer, a short plateau region appeared when shear movement was from copper to iron.展开更多
The extraction and separation of Cu(Ⅱ)and Fe(Ⅲ)from HCl media using Cyanex 921 in kerosene were investigated.The effect of shaking time,aqueous phase acid concentration,Fe(Ⅲ)/Cu(Ⅱ)concentration,Cyanex 921 concentr...The extraction and separation of Cu(Ⅱ)and Fe(Ⅲ)from HCl media using Cyanex 921 in kerosene were investigated.The effect of shaking time,aqueous phase acid concentration,Fe(Ⅲ)/Cu(Ⅱ)concentration,Cyanex 921 concentration,temperature and aqueous to organic phase ratio on the separation of Cu(Ⅱ)and Fe(Ⅲ)was studied using 0.1 mol/L Cyanex 921 in kerosene.Maximum separation was achieved from 2 mol/L HCl containing 0.001 mol/L Cu(Ⅱ)and 0.005 mol/L Fe(Ⅲ)with 0.1 mol/L Cyanex 921 in kerosene.Feasible separation of copper and iron was also possible from 5 mol/L HCl using 0.02 mol/L Cyanex 921.展开更多
The aim of this study was to evaluate the effect of copper and iron on acidogenic biomass immobilized on clinoptilolite in an anaerobic packed bed reactor. Copper and iron were fed to the reactor at concentrations of ...The aim of this study was to evaluate the effect of copper and iron on acidogenic biomass immobilized on clinoptilolite in an anaerobic packed bed reactor. Copper and iron were fed to the reactor at concentrations of 100 and 300 mg·L-1, respectively. Both metal ions had insignificant inhibitory effect over the metabolism of the biomass, specifically, on substrate consumption and production of volatile fatty acids (VFAs). The microstructural characterization of the biofilm by Scanning Electron Microscopy showed no effect on the morphology of the microorganisms after the metals treatment. Copper and iron removal was also measured in the reactor, achieving a breakthrough time of 3 days, during which removal efficiencies were higher than 90%. It was also observed that the biomass had a greater affinity for copper. The results indicate that acidogenic biomass can be used effectively as a sorbent agent. The pollution of river-streams with heavy metals—mainly copper and iron—was one of the most compelling motivations for conducting this investigation. The San Pedro River Basin, a trans-boundary river that originates near the mining town of Cananea, Sonora, México, and flows to Arizona, USA, exemplifies this environmental issue.展开更多
This study aimed to investigate the effects of copper and manganese on hemocyte apoptosis and the antagonism of iron and zinc in Oreochromis niloticus The heavy metal contents in fish blood and feed were determined by...This study aimed to investigate the effects of copper and manganese on hemocyte apoptosis and the antagonism of iron and zinc in Oreochromis niloticus The heavy metal contents in fish blood and feed were determined by atomic absorption spectrophotometry, and the hemocyte apoptosis was determined by flow cytometry. A total of 360 tilapias were selected, and they were divided randomly and evenly into 12 groups. In the challenge groups, the tilapias were fed with con stant-level copper sulfate(0, 200 mg/kg) and manganese sulfate(0, 120 mg/kg); in the antagonism groups, the tilapias were fed with constant-level zinc sulfate(20320 mg/kg) and iron sulfate(150, 350 mg/kg). After 20-week aquaculture, the hemocyte apoptosis rates in the copper and manganese groups were significantly increased; with the increased addition levels of iron and zinc, the hemocyte apopto sis rates in the iron and zinc groups were significantly reduced, but they were stil higher than that in the control group. In conclusion, excessive copper and manganese can cause apoptosis in hemocytes of O. niloticus. However, the toxic effects of copper and manganese can be antagonized by iron and zinc.展开更多
The clinical signs of Tibetan sheep with sulphur- and iron-induced copper deficiency in Maqu County of Gansu Province were defined as thin, decreased appetite, neonatal ataxia, pica, emaciation, and loss of hair color...The clinical signs of Tibetan sheep with sulphur- and iron-induced copper deficiency in Maqu County of Gansu Province were defined as thin, decreased appetite, neonatal ataxia, pica, emaciation, and loss of hair color and anemia. The mineral composition of soil and forage, and samples of liver, blood and hair from Tibetan sheep in affected ranches in this region were compared with those from unaffected areas. The mean concentration of iron in soil and forage in affected pasture was 19 675 ±791 and 1 763 ±197 μg/g, respectively, compared with 8 761 ±871 and 357 ±39 μg/g in unaffected pasture. The mean concentration of sulphur in soil and forage in affected pasture was 1.98% ±0.79% and 0.88% ±0.16%, respectively, compared with 1.16%±0.26% and 0.47%±0.16%in unaffected pasture. The mean copper concentrations in soil and forage from the affected pastures were 15.9±1.8 and 6.7±1.6 μg/g, respectively, compared with 16.7±1.9 and 8.9±2.7 μg/g in unaffected pasture.The mean concentration of Cu in blood, liver, and hair from the affected Tibetan sheep were 0.32±0.12, 51.2±3.1 and 2.16±0.65μg/g, respectively, compared with 0.76±0.21, 191±11 and 3.27±0.96 μg/g for healthy animals. Oral administration of CuClO(OH)3prevented and cured anemia. We conclude that wool eating of Tibetan sheep in this region is probably caused by secondary Cu deficiency, mainly due to the high iron and sulphur contents in soils and forage.展开更多
The effects of ferrous and ferric iron as well as redox potential on copper and iron extraction from the copper flotation concentrate of Sarcheshmeh, Kerman, Iran, were evaluated using shake flask leaching examination...The effects of ferrous and ferric iron as well as redox potential on copper and iron extraction from the copper flotation concentrate of Sarcheshmeh, Kerman, Iran, were evaluated using shake flask leaching examinations. Experiments were carried out in the presence and absence of a mixed culture of moderately thermophile microorganisms at 50?C. Chemical leaching experiments were performed in the absence and presence of 0.15 M iron (ferric added medium, ferrous added medium and a mixture medium regulated at 420 mV, Pt. vs. Ag/AgCl). In addition, bioleaching experiments were carried out in the presence and absence of 0.1 M iron (ferric and ferrous added mediua) at pulp density 10% (w/v), inoculated bacteria 20% (v/v), initial pH 1.6, nutrient medium Norris and yeast extract addition 0.02% (w/w). Abiotic leaching tests showed that the addition of iron at low solution redox potentials significantly increased the rate and extent of copper dissolution but when ferric iron was added, despite a higher initial rate of copper dissolution, leaching process stopped. Addition of both ferrous and ferric iron to the bioleaching medium levelled off the copper extraction and had an inhibitory effect which decreased the final redox potential. The monitoring of ferrous iron, ferric iron and copper extraction in leach solutions gave helpful results to understand the behaviour of iron cations during chemical and bacterial leaching processes.展开更多
Background and objective The expression of various trace elements and markers in lung cancer is controversial.The aim of this study is to evaluate the presence of calcium(Ca),copper(Cu),iron(Fe) and carcinoembryonic a...Background and objective The expression of various trace elements and markers in lung cancer is controversial.The aim of this study is to evaluate the presence of calcium(Ca),copper(Cu),iron(Fe) and carcinoembryonic antigen(CEA) in cancerous untreated lung tissues and to determine a possible association between these markers and lung cancer.Methods Fourty-eight cancerous lung tissue blocks,from Sultan Qaboos University Hospital,Sultanate of Oman,were studied.Fe,Ca,Cu,and CEA were demonstrated in the tissue blocks using Perl's Prussian blue,Von Kossa's,modified rhodanine and immunohistochemical staining methods,respectively.Results Twenty-three of 48 specimens showed positive Fe staining,2 showed positive Ca staining and Cu was absent in all specimens.93.7% expressed CEA in varying degree of positivity.81.25% of these sections showed high expression of CEA.Conclusion Tissue concentrations of trace elements were not elevated in lung cancer and therefore cannot be considered as a potential marker.Despite the low sensitivity and specificity of CEA as previously reported,tissue CEA should be considered as a potential marker in the evaluation of lung cancer.展开更多
Iron and copper have a wealth of functions in biological systems,which makes them essential micronutrients for all living organisms.Defects in iron and copper homeostasis are directly responsible for diseases,and have...Iron and copper have a wealth of functions in biological systems,which makes them essential micronutrients for all living organisms.Defects in iron and copper homeostasis are directly responsible for diseases,and have been linked to impaired development,metabolic syndromes and fungal virulence.Consequently,it is crucial to gain a comprehensive understanding of the molecular bases of iron-and copper-dependent proteins in living systems.Simon Labbémaintains parallel programs on iron and copper homeostasis using the fission yeast Schizosaccharomyces pombe(Schiz.pombe) as a model system.The study of fission yeast transition-metal metabolism has been successful,not only in discerning the genes and pathways functioning in Schiz.pombe,but also the genes and pathways that are active in mammalian systems and for other fungi.展开更多
This study assessed the iron, zinc and copper status of primary school-attending children in Lagos. A sample of 200 primary School-attending children was randomly selected using a stratified 2 – stage sampling techni...This study assessed the iron, zinc and copper status of primary school-attending children in Lagos. A sample of 200 primary School-attending children was randomly selected using a stratified 2 – stage sampling technique. Data was collected in the 2 major seasons in Nigeria;Dry and Rainy seasons using dietary intake (24 hr dietary recall protocol) venipuncture blood samples, and a self-administered questionnaire. The data were analyzed using descriptive and inferential statistics. Among ages 5 - 8 years, the main dietary intake for iron was 10.66 ± 12.44 mg/d (106% of DRI), for zinc, 7.30 ± 7.39 mg/d (92% of DRI) and for copper, 1.55 ± 1.31 mg/d (390% of DRI). For ages 9 - 13 yrs, the mean intake of micronutrients showed that iron was 11.03 ± 12.72 mg/d (138% of DRI), 3inc was 8.44 ± 7.7 mg/d (105% of DRI) and copper was 3.75 ± 15.17 mg/d (536% of DRI). Biochemical results indicated that 19.8% of the subjects had inadequate serum iron, 21% and 32.1% were zinc and copper deficient respectively prevalence of anemia was 38.1% while iron deficiency anemia was 13.06% and iron deficiency was 34.6%. Dietary intakes did not provide right amounts of micronutrients to meet body requirements. There is the need to formulate and implement nutrition education programs to correct micronutrient deficiency among primary school-attending children in Lagos, Nigeria.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
The influences of copper on microstructure and the hardening behavior of high chromium cast irons subjected to sub-critical treatment were investigated. The results show that the microstructure of the as-cast high chr...The influences of copper on microstructure and the hardening behavior of high chromium cast irons subjected to sub-critical treatment were investigated. The results show that the microstructure of the as-cast high chromium cast irons consists of retained austenite, martensite and M1C3 type eutectic carbide. When copper is added into high chromium cast irons, austenite and carbide contents are increased. The increased addition of copper content from 0% to 1.84% leads to the increase of austenite and carbide from 15.9% and 20. 0% to 61.0% and 35.5% , respectively. In the process of sub-critical treatment, the retained austenite in the matrix can be precipitated into secondary carbides and then transforms into martensite in cooling process, which causes the secondary hardening of the alloy under sub-critical treatment. High chromium cast irons containing copper in sub-critical treatment appear the second hardening curve peak due to the precipitation of copper from supersaturated matrix.展开更多
This paper is a brief overview of the role of inducing the nucleated electro winning of copper by using iron electrodes in electrocoagulation (EC) process. Cyanide compounds are widely used in gold ore processing plan...This paper is a brief overview of the role of inducing the nucleated electro winning of copper by using iron electrodes in electrocoagulation (EC) process. Cyanide compounds are widely used in gold ore processing plants in order to facilitate the extraction and subsequent concentration of the precious metal. Owing to cyanide solution employed in gold processing, effluents generated have high contents of free cyanide as well as copper cyanide complexes, which lend them a high degree of toxicity. In this regard, two options for the treatment of cyanide barren solutions has been used;in two ways;first for cyanide destruction by oxidation with the use of the EC process, in theory, has the advantage of decomposing cyanide at the anode and collecting copper simultaneously by a sludge of copper magnetic iron. In both cases excellent performance can be achieved using the high capacity of the bipolar iron EC technology. We found that it is possible to reduce the copper cyanide complex from 720 mg·l-1 to below 10 mg·l-1 within 20 minutes.展开更多
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
基金funded by the Shenzhen Key Medical Discipline Construction Fund(S ZXK046)the National Nature Science Foundation of China(81571869).
文摘BACKGROUND:This study aims to evaluate the eff ect of continuous renal replacement therapy(CRRT)on inflammation-related anemia,iron metabolism,and the prognosis in sepsis patients with acute kidney injury(AKI).METHODS:Sepsis patients with AKI were prospectively enrolled and randomized into the CRRT and control groups.The clinical and laboratory data on days 1,3 and 7 after intensive care unit(ICU)admission were collected.The serum interleukin(IL)-6,hepcidin,erythropoietin,ferritin,and soluble transferrin receptor(sTfR)were determined by enzyme-linked immunosorbent assay.The Sequential Organ Failure Assessment(SOFA)score and 28-day mortality were recorded.Data were analyzed using Pearson’s Chi-square test or Fisher’s exact test(categorical variables),and Mann-Whitney U-test or t-test(continuous variables).RESULTS:The hemoglobin and serum erythropoietin levels did not signifi cantly diff er between the CRRT and control groups though gradually decreased within the first week of ICU admission.On days 3 and 7,the serum IL-6,hepcidin,ferritin,and red blood cell distribution width significantly decreased in the CRRT group compared to the control group(all P<0.05).On day 7,the serum iron was significantly elevated in the CRRT group compared to the control group(P<0.05).However,the serum sTfR did not signifi cantly diff er between the groups over time.In addition,the SOFA scores were signifi cantly lower in the CRRT group compared to the control group on day 7.The 28-day mortality did not signifi cantly diff er between the control and CRRT groups(38.0%vs.28.2%,P=0.332).CONCLUSION:CRRT might have beneficial effects on the improvement in inflammationrelated iron metabolism and disease severity during the fi rst week of ICU admission but not anemia and 28-day mortality in sepsis patients with AKI.
基金Project(Y2010-1-005)supported by the Collaborative Fund of Hunan Nonferrous Metals Holding Group-Central South University,China
文摘It is important to remove the impurities, such as copper and cadmium, from leaching solution in zinc hydrometallurgy. To improve purification efficiency, a replacement-column purification device was proposed and its mass transfer characteristics and purification efficiency were experimentally studied. The results show that purification efficiency increases with the decrease of the zinc powder diameter and decreases with the increase of solution velocity. If appropriate structure and operation parameters are used, it is possible to make purification efficiency more than 99%, but the diameter of zinc powder should be larger than 0.45 mm. For the velocity of 0.05-0.7 cm/s, mass transfer coefficient kc is in the range of 3.94×10-7-2.76×10-6 m/s, and increases with the decrease of zinc powder diameter and the increase of solution velocity. Moreover, it can be derived by mass transfer correlations of Sherwood number:Sh=0.1069Re0.5Sc0.33, for 0.3<Re<6.
基金financially supported by the National Natural Science Foundation of China (No. 51674026)
文摘Currently, the majority of copper tailings are not effectively developed. Worldwide, large amounts of copper tailings generated from copper production are continuously dumped, posing a potential environmental threat. Herein, the recovery of iron from copper tailings via low-temperature direct reduction and magnetic separation was conducted; process optimization was carried out, and the corresponding mineralogy was investigated. The reduction time, reduction temperature, reducing agent (coal), calcium chloride additive, grinding time, and magnetic field intensity were examined for process optimization. Mineralogical analyses of the sample, reduced pellets, and magnetic concentrate under various conditions were performed by X-ray diffraction, optical microscopy, and scanning electron microscopy-energy-dispersive X-ray spectrometry to elucidate the iron reduction and growth mechanisms. The results indicated that the optimum parameters of iron recovery include a reduction temperature of 1150A degrees C, a reduction time of 120 min, a coal dosage of 25%, a calcium chloride dosage of 2.5%, a magnetic field intensity of 100 mT, and a grinding time of 1 min. Under these conditions, the iron grade in the magnetic concentrate was greater than 90%, with an iron recovery ratio greater than 95%.
文摘In this paper,the combined addition of copper or iron and sulphate ions onto TiO_(2) prepared by a simple sol-gel method is studied for formic acid photocatalytic conversion.A wide structural and morphological characterization of the different photocatalysts was performed by X-ray diffraction(XRD),N_(2)-physisorption for BET surface area measurements,scanning and transmission electronic microscopies(SEM and TEM),UV-Vis diffuse spectroscopy(DRS)and X-ray photoelectron spectroscopy(XPS),in order to correlate the physico-chemical properties of the materials to their photocatalytic efficiencies for formic acid oxidation.Results have shown important differences among the catalysts depending on the metal added.Sulphated TiO_(2)/Cu(1%Cu)was the best photocatalyst obtaining about 100% formic acid conversion in only 5 min.The appropriate physico-chemical features of this photocatalyst,given by the addition of combined copper and sulphate ions,explain its excellence in photocatalytic reaction.
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 selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone(2-PYAINH) was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At a pH value of 7.0, 9,0, 9.0, and 8.0, respectively, which greatly increased the selectivity; nickel, copper, cobalt, and iron reacted with 2-PYAINH to form a 1:2 yellow-orange, 1:2 yellow-green, 1:2 yellow and 1:1 yellow complexes, with absorption peaks at 363, 352, 346, and 359 nm, respectively. Under the optimal conditions, Beer's law was obeyed over the ranges of 0.01-1.4, 0.01-1.5, 0.01-2.7, and 0.01-5.4 mg/L respectively. The apparent molar absorptivity and Sandell's sensitivities were 8.4×10^4, 5.2×10^4, 7.1×10^4, and 3.9×10^4 L·mol^-l·cm^-1, respectively, and 0.00069, 0.0012, 0.00078, and 0.0014 μg·cm2, respectively. The detection limits were found to be 0.001, 0.002, 0.003, and 0.01 mg/L, respectively. The detailed study of various interfering ions to make the method more sensitive was carried out and selective and several real samples were analyzed with satisfactory results.
基金financially supported by the National Natural Science Foundation of China (No. 51575132)
文摘In the present study, pure iron/copper composite metal cladding was deposited onto carbon steel by tungsten inert gas welding. The study focused on interfacial morphological, microstructural, and mechanical analyses of the composite cladding layers. Iron liquid–solid-phase zones were formed at copper/steel and iron interfaces because of the melting of the steel substrate and iron. Iron concentrated in the copper cladding layer was observed to exhibit belt, globule, and dendrite morphologies. The appearance of iron-rich globules indicated the occurrence of liquid phase separation(LPS) prior to solidification, and iron-rich dendrites crystallized without the occurrence of LPS. The maximum microhardness of the iron/steel interface was lower than that of the copper/steel interface because of the diffusion of elemental carbon. All samples fractured in the cladding layers. Because of a relatively lower strength of the copper layer, a short plateau region appeared when shear movement was from copper to iron.
文摘The extraction and separation of Cu(Ⅱ)and Fe(Ⅲ)from HCl media using Cyanex 921 in kerosene were investigated.The effect of shaking time,aqueous phase acid concentration,Fe(Ⅲ)/Cu(Ⅱ)concentration,Cyanex 921 concentration,temperature and aqueous to organic phase ratio on the separation of Cu(Ⅱ)and Fe(Ⅲ)was studied using 0.1 mol/L Cyanex 921 in kerosene.Maximum separation was achieved from 2 mol/L HCl containing 0.001 mol/L Cu(Ⅱ)and 0.005 mol/L Fe(Ⅲ)with 0.1 mol/L Cyanex 921 in kerosene.Feasible separation of copper and iron was also possible from 5 mol/L HCl using 0.02 mol/L Cyanex 921.
文摘The aim of this study was to evaluate the effect of copper and iron on acidogenic biomass immobilized on clinoptilolite in an anaerobic packed bed reactor. Copper and iron were fed to the reactor at concentrations of 100 and 300 mg·L-1, respectively. Both metal ions had insignificant inhibitory effect over the metabolism of the biomass, specifically, on substrate consumption and production of volatile fatty acids (VFAs). The microstructural characterization of the biofilm by Scanning Electron Microscopy showed no effect on the morphology of the microorganisms after the metals treatment. Copper and iron removal was also measured in the reactor, achieving a breakthrough time of 3 days, during which removal efficiencies were higher than 90%. It was also observed that the biomass had a greater affinity for copper. The results indicate that acidogenic biomass can be used effectively as a sorbent agent. The pollution of river-streams with heavy metals—mainly copper and iron—was one of the most compelling motivations for conducting this investigation. The San Pedro River Basin, a trans-boundary river that originates near the mining town of Cananea, Sonora, México, and flows to Arizona, USA, exemplifies this environmental issue.
基金Supported by Scientific Operating Expenses of Hainan Province(11-201410-0009)~~
文摘This study aimed to investigate the effects of copper and manganese on hemocyte apoptosis and the antagonism of iron and zinc in Oreochromis niloticus The heavy metal contents in fish blood and feed were determined by atomic absorption spectrophotometry, and the hemocyte apoptosis was determined by flow cytometry. A total of 360 tilapias were selected, and they were divided randomly and evenly into 12 groups. In the challenge groups, the tilapias were fed with con stant-level copper sulfate(0, 200 mg/kg) and manganese sulfate(0, 120 mg/kg); in the antagonism groups, the tilapias were fed with constant-level zinc sulfate(20320 mg/kg) and iron sulfate(150, 350 mg/kg). After 20-week aquaculture, the hemocyte apoptosis rates in the copper and manganese groups were significantly increased; with the increased addition levels of iron and zinc, the hemocyte apopto sis rates in the iron and zinc groups were significantly reduced, but they were stil higher than that in the control group. In conclusion, excessive copper and manganese can cause apoptosis in hemocytes of O. niloticus. However, the toxic effects of copper and manganese can be antagonized by iron and zinc.
基金Supported by the China Agriculture Research System(CARS-35-37)the Guizhou Provincial Science and Technology Foundation Project([2014]6017)
文摘The clinical signs of Tibetan sheep with sulphur- and iron-induced copper deficiency in Maqu County of Gansu Province were defined as thin, decreased appetite, neonatal ataxia, pica, emaciation, and loss of hair color and anemia. The mineral composition of soil and forage, and samples of liver, blood and hair from Tibetan sheep in affected ranches in this region were compared with those from unaffected areas. The mean concentration of iron in soil and forage in affected pasture was 19 675 ±791 and 1 763 ±197 μg/g, respectively, compared with 8 761 ±871 and 357 ±39 μg/g in unaffected pasture. The mean concentration of sulphur in soil and forage in affected pasture was 1.98% ±0.79% and 0.88% ±0.16%, respectively, compared with 1.16%±0.26% and 0.47%±0.16%in unaffected pasture. The mean copper concentrations in soil and forage from the affected pastures were 15.9±1.8 and 6.7±1.6 μg/g, respectively, compared with 16.7±1.9 and 8.9±2.7 μg/g in unaffected pasture.The mean concentration of Cu in blood, liver, and hair from the affected Tibetan sheep were 0.32±0.12, 51.2±3.1 and 2.16±0.65μg/g, respectively, compared with 0.76±0.21, 191±11 and 3.27±0.96 μg/g for healthy animals. Oral administration of CuClO(OH)3prevented and cured anemia. We conclude that wool eating of Tibetan sheep in this region is probably caused by secondary Cu deficiency, mainly due to the high iron and sulphur contents in soils and forage.
文摘The effects of ferrous and ferric iron as well as redox potential on copper and iron extraction from the copper flotation concentrate of Sarcheshmeh, Kerman, Iran, were evaluated using shake flask leaching examinations. Experiments were carried out in the presence and absence of a mixed culture of moderately thermophile microorganisms at 50?C. Chemical leaching experiments were performed in the absence and presence of 0.15 M iron (ferric added medium, ferrous added medium and a mixture medium regulated at 420 mV, Pt. vs. Ag/AgCl). In addition, bioleaching experiments were carried out in the presence and absence of 0.1 M iron (ferric and ferrous added mediua) at pulp density 10% (w/v), inoculated bacteria 20% (v/v), initial pH 1.6, nutrient medium Norris and yeast extract addition 0.02% (w/w). Abiotic leaching tests showed that the addition of iron at low solution redox potentials significantly increased the rate and extent of copper dissolution but when ferric iron was added, despite a higher initial rate of copper dissolution, leaching process stopped. Addition of both ferrous and ferric iron to the bioleaching medium levelled off the copper extraction and had an inhibitory effect which decreased the final redox potential. The monitoring of ferrous iron, ferric iron and copper extraction in leach solutions gave helpful results to understand the behaviour of iron cations during chemical and bacterial leaching processes.
基金Supported by the National Natural Science Foundation of China(30270924) Natural Science Foundation of Anhui Province (070411004) +1 种基金 the National Science Foundation of Education Department of Anhui Province(2006KJ184B) the Foundation of Provincial Key Lab of Biotic Environment and Ecological Safety in Anhui Province
文摘Background and objective The expression of various trace elements and markers in lung cancer is controversial.The aim of this study is to evaluate the presence of calcium(Ca),copper(Cu),iron(Fe) and carcinoembryonic antigen(CEA) in cancerous untreated lung tissues and to determine a possible association between these markers and lung cancer.Methods Fourty-eight cancerous lung tissue blocks,from Sultan Qaboos University Hospital,Sultanate of Oman,were studied.Fe,Ca,Cu,and CEA were demonstrated in the tissue blocks using Perl's Prussian blue,Von Kossa's,modified rhodanine and immunohistochemical staining methods,respectively.Results Twenty-three of 48 specimens showed positive Fe staining,2 showed positive Ca staining and Cu was absent in all specimens.93.7% expressed CEA in varying degree of positivity.81.25% of these sections showed high expression of CEA.Conclusion Tissue concentrations of trace elements were not elevated in lung cancer and therefore cannot be considered as a potential marker.Despite the low sensitivity and specificity of CEA as previously reported,tissue CEA should be considered as a potential marker in the evaluation of lung cancer.
基金Supported by The Canadian Institutes for Health Research (MOP-36450 to LabbéS)Natural Sciences and Engineering Research Council of Canada(MOP-238238-2010 to LabbéS)the Fonds de la Recherche en Santédu Québec(Senior Investigator Scholarship to LabbéS)
文摘Iron and copper have a wealth of functions in biological systems,which makes them essential micronutrients for all living organisms.Defects in iron and copper homeostasis are directly responsible for diseases,and have been linked to impaired development,metabolic syndromes and fungal virulence.Consequently,it is crucial to gain a comprehensive understanding of the molecular bases of iron-and copper-dependent proteins in living systems.Simon Labbémaintains parallel programs on iron and copper homeostasis using the fission yeast Schizosaccharomyces pombe(Schiz.pombe) as a model system.The study of fission yeast transition-metal metabolism has been successful,not only in discerning the genes and pathways functioning in Schiz.pombe,but also the genes and pathways that are active in mammalian systems and for other fungi.
文摘This study assessed the iron, zinc and copper status of primary school-attending children in Lagos. A sample of 200 primary School-attending children was randomly selected using a stratified 2 – stage sampling technique. Data was collected in the 2 major seasons in Nigeria;Dry and Rainy seasons using dietary intake (24 hr dietary recall protocol) venipuncture blood samples, and a self-administered questionnaire. The data were analyzed using descriptive and inferential statistics. Among ages 5 - 8 years, the main dietary intake for iron was 10.66 ± 12.44 mg/d (106% of DRI), for zinc, 7.30 ± 7.39 mg/d (92% of DRI) and for copper, 1.55 ± 1.31 mg/d (390% of DRI). For ages 9 - 13 yrs, the mean intake of micronutrients showed that iron was 11.03 ± 12.72 mg/d (138% of DRI), 3inc was 8.44 ± 7.7 mg/d (105% of DRI) and copper was 3.75 ± 15.17 mg/d (536% of DRI). Biochemical results indicated that 19.8% of the subjects had inadequate serum iron, 21% and 32.1% were zinc and copper deficient respectively prevalence of anemia was 38.1% while iron deficiency anemia was 13.06% and iron deficiency was 34.6%. Dietary intakes did not provide right amounts of micronutrients to meet body requirements. There is the need to formulate and implement nutrition education programs to correct micronutrient deficiency among primary school-attending children in Lagos, Nigeria.
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.
文摘The influences of copper on microstructure and the hardening behavior of high chromium cast irons subjected to sub-critical treatment were investigated. The results show that the microstructure of the as-cast high chromium cast irons consists of retained austenite, martensite and M1C3 type eutectic carbide. When copper is added into high chromium cast irons, austenite and carbide contents are increased. The increased addition of copper content from 0% to 1.84% leads to the increase of austenite and carbide from 15.9% and 20. 0% to 61.0% and 35.5% , respectively. In the process of sub-critical treatment, the retained austenite in the matrix can be precipitated into secondary carbides and then transforms into martensite in cooling process, which causes the secondary hardening of the alloy under sub-critical treatment. High chromium cast irons containing copper in sub-critical treatment appear the second hardening curve peak due to the precipitation of copper from supersaturated matrix.
文摘This paper is a brief overview of the role of inducing the nucleated electro winning of copper by using iron electrodes in electrocoagulation (EC) process. Cyanide compounds are widely used in gold ore processing plants in order to facilitate the extraction and subsequent concentration of the precious metal. Owing to cyanide solution employed in gold processing, effluents generated have high contents of free cyanide as well as copper cyanide complexes, which lend them a high degree of toxicity. In this regard, two options for the treatment of cyanide barren solutions has been used;in two ways;first for cyanide destruction by oxidation with the use of the EC process, in theory, has the advantage of decomposing cyanide at the anode and collecting copper simultaneously by a sludge of copper magnetic iron. In both cases excellent performance can be achieved using the high capacity of the bipolar iron EC technology. We found that it is possible to reduce the copper cyanide complex from 720 mg·l-1 to below 10 mg·l-1 within 20 minutes.
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.