Microstructure and properties of pure iron/copper composite cladding layers on carbon steel

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.

Iron and copper recovery from copper slags through smelting with waste cathode carbon from aluminium electrolysis

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%.

Influence of Ferric and Ferrous Iron on Chemical and Bacterial Leaching of Copper Flotation Concentrates

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.

Tissue Carcinoembryonic Antigen,Calcium,Copper and Iron Levels in Cancerous Lung Patients

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.

Recovery of iron from copper tailings via low-temperature direct reduction and magnetic separation: process optimization and mineralogical study

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%.

Effect of Copper and Iron on Acidogenic Biomass in an Anaerobic Packed Bed Reactor

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&middotL-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.

Simon Labbé's work on iron and copper homeostasis

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.

Iron, Zinc, and Copper Malnutrition among Primary School Children in Lagos, Niagara

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.

Effect of Ceria on Structure and Thermostability of Copper-Iron-Oxide Catalyst

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.

Experiment Research on the Enrichment of Precious Metals from Nickel-copper-iron Matte

According to the chemical and phase composition of the nickel-copper-iron matte containing precious metals and the progress in enrichment of precious metals from the nickel-copper-iron matte containing precious metals at home and abroad, this paper put forward the process route of enrichment of precious metals and selectively leaching of base metals from the nickel-copper-iron matte by sulfuric acid and sodium hypochlorite. The effects of particle size, leaching temperature, leaching time, amount of sulfuric acid and sodium hypochlorite on the leaching rate of nickel, cobalt, copper and iron are mainly discussed. The results show that raw material particle size has significantly effects on the leaching rate of base metals, high leaching rate of base metals and enrichment of precious metals are obtained with the suitable particle size. Through the experiments, the reasonable experiment parameters and conditions were determined as fellows: particle size of-200 to +250 mesh, leaching temperature 95℃ , leaching time 5 h, sulfuric acid concentration 30%, adding amount of sodium hypochlorite 3 times of matte weight. Under these experiment parameters and conditions, the leaching rate of nickel, cobalt, copper and iron were 97.39%, 96.24%, 98.30% and 99.01%, respectively. The content of nickel, cobalt, copper, iron in the leaching residues was 8.15%, 0.23%, 1.40% and 0.24%, respectively. The content of Pt, Pd, Au, Ag and Rh in the leaching residues was 247 g/t, 521 g/t, 112 g/t, 494 g/t and 24 g/t, respectively. The content of Pt, Pd, Au, Ag and Rh in the leaching solution was <0.0005 g/L, 0.0023 g/L, 0.0007 g/L, <0.0005 g/L and 0.00017 g/L, respectively. This process has advantages as follows: a small investment, simple technology, high enrichment efficiency.

Geological - Geophysical - Geochemical Exploration Models of Copper - Iron Deposits in Southeastern Hubei

This paper discusses geological-geophysical-geochemical models of such typical deposits as the Tieshan-type Fe-Cu deposit, the Tonglushan-type Cu-Fe deposit, the Yehuaxiang-type Cu deposit, the Jiguanzui-type Cu-Au deposit, and the Tongshankou-type Cu (Mo) deposit. The models were established based on practical data of the polymetallic deposits dominated by copper ore in southeastern Hubei. These models, which are graphically illustrated in the paper, systematically summarize the metallogenic geological conditions and the geophysical-geochemical characteristics of copper deposits in this area. The models are of practical significance for studying copper deposits, predicting mineral resources, choosing exploration methods, and searching for ore deposits based on existing ones in the study area.

Petrology, Structural and Geochemistry of the Copper-Nickle-Iron Bearing Rocks in Korr-Marsabit Area, Northern Kenya

The main objective of this study was to investigate copper-Nickle-Iron bearing rocks of the northern Kenya, and understand their mode of formation. The area of study is bounded by latitudes 2&#186;52'00"N and 1&#186;52'00"N and longitudes 37&#186;19'00"E and 37&#186;36'00"E, South West of Marsabit town. The methods involved geological field mapping between September, 2020 and December 2020. Elemental analyses of the samples were done using an XRF. Pearsonian correlation on the analyzed elements was done using Oasis Montaj 8.4. Fabric8 software was used to analyze structural data. The area comprises metamorphic, igneous and sedimentary rocks. Metamorphic rocks include biotite hornblende gneisses, biotite gneisses, biotite muscovite gneisses and marbles. Basalts of different mineralogy were also found in the area. Colluvium and alluvium sediments were found covering some of the metamorphic rocks in some areas. Malachite occurs in gneisses in the central part of the area. The area has undergone deformation, which includes jointing and folding. The fold axis trend in the North-South direction and plunges to the southern part of the area. Correlation of the elements shows that there is a positive correlation of Copper-Nickel-Iron. This indicates similar mode of delivery within the host rocks. Kriging indicates spatial distribution of these elements within the study area. The average size of distribution can easily be computed from the maps produced by kriging.

Simple, Selective, and Sensitive Spectrophotometric Method for Determination of Trace Amounts of Nickel(Ⅱ), Copper (Ⅱ), Cobalt (Ⅱ), and Iron (Ⅲ) with a Novel Reagent 2-Pyridine Carboxaldehyde Isonicotinyl Hydrazone

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.

Copper Recovery from Barren Cyanide Solution by Using Electrocoagulation Iron Process

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.

铁铜负载生物炭催化H_(2)O_(2)降解药物类新污染物研究

以花生壳为原材料,高铁酸钾(K_(2)FeO_(4))、Cu(NO_(3))_(2)为活化剂和金属源通过一步热解法,制备铁铜负载石墨化生物炭催化剂(FCBC)构建FCBC-H_(2)O_(2)非均相Fenton体系,考察其对盐酸四环素(TC)和对乙酰氨基酚(ACE)的降解效果及机理。结果表明,在最佳反应条件pH=3、FCBC投加量为0.7 g/L、H_(2)O_(2)浓度为10 mmol/L条件下,可有效降解98%的TC和97%的ACE。在pH=2~6范围内,FCBC均具有较高的催化性能,反应体系主要受H_(2)O_(2)投加量影响。通过SEM、XRD、FTIR、XPS、BET等方法对FCBC催化剂的结构进行表征,FCBC石墨化程度较高,拥有丰富的孔结构和较大的比表面积(685.11 m^(2)/g),生物炭表面铁元素主要以Fe0和Fe_(3)O_(4)形态,铜元素主要以Cu^(0)形态存在。Cu^(0)不仅增加生物炭表面吸附和催化活性位点,还可加速Fe^(2+)/Fe^(3+)的循环提高反应催化效率。FCBC催化材料稳定具有良好的重复利用率,在实际水体模拟试验中表现出良好的催化性能。研究成果可为非均相芬顿降解药物类新污染物的催化材料选择和应用提供指导和支持。

火焰原子吸收光谱法测定配合饲料中铜、铁和锰含量的不确定度评定

研究旨在建立火焰原子吸收光谱法测定配合饲料中铜、铁和锰含量的不确定度评定方法,真实反映测量的置信度和准确性。首先分析测定过程中的不确定度来源,对不确定度分量进行量化,然后通过数学模型计算出饲料中铜、铁和锰含量,合成扩展不确定度。结果显示:饲料中铜、铁和锰的含量分别为(11±2)、(214±10)、(92±4)mg/kg,不确定度为扩展不确定度,包含因子为2,对应的置信水平是95%。本研究发现样品消解、样品溶液浓度测定和含量重复性测量是影响饲料中铜、铁、锰含量测量中不确定度的主要因素,应特别关注样品的前处理过程、标准工作液的配制,并使待测样品的浓度落在曲线的中间位置,以提高检测准确性。

智利月亮山地区中生代侵入岩成因及其构造意义:来自锆石U-Pb年代学、岩石地球化学的制约

月亮山铁铜矿区处于智利中北部海岸山带铁氧化物铜金矿(IOCG)成矿带上,位于一级控矿构造阿塔卡玛(ATACAMA)断裂带的南缘。全岩地球化学研究表明,本区二长闪长岩性质具有钙碱性、准铝质特征,其La/Nb比值大于1.5,La/Ta比值大于22,微量元素图显示均显著亏损Nb、Ta和Ti,表明二长闪长岩岩浆的源区起源于与俯冲相关的岩石圈地幔。二长闪长岩的LA-ICP-MS锆石U-Pb年龄为(108.2±1.9)Ma,表明其为早白垩世晚期的岩浆活动的产物。构造环境分析表明,太平洋纳斯卡板块向南美板块俯冲过程中,形成本区南北向的ATACAMA断裂带(AFZ)与母岩浆,深层岩浆侵位经过部分熔融、结晶分异过程形成了闪长岩岩体,与本区IOCG矿床的形成关系密切。

基于金纳米棒刻蚀比色法检测铁、铜离子

采用种子生长法制备金纳米棒(AuNRs)以构建光学传感器,用于Fe^(3+)和Cu^(2+)的高选择性快速可视化检测。在酸性环境中,Fe^(3+)和Cu^(2+)通过与KI溶液反应,将I-氧化成I2。I2刻蚀AuNRs,导致其纵向表面等离子体共振(LSPR)吸收峰蓝移,从而实现对Fe^(3+)和Cu^(2+)的检测。结果表明,反应温度为50℃时,添加0.8 mL 0.1 mol·L^(-1)HCl、2 mL AuNRs生长液和20 mmol·L^(-1)KI溶液,与2 mL 500μmol·L^(-1)Fe^(3+)或30μmol·L^(-1)Cu^(2+)反应25或90 min,可将AuNRs刻蚀至LSPR吸收峰消失。该方法对Fe^(3+)和Cu^(2+)检测具有高选择性和准确性,对于Fe^(3+)、Cu^(2+)共存体系的检测,可通过加入适量F-与Fe^(3+)生成配合物[FeF_(6)]^(3-)完成对Fe^(3+)的化学掩蔽,消除Fe^(3+)的干扰,实现共存体系中Cu^(2+)的准确检测。

石墨烯含量对铜铁基自润滑摩擦材料组织结构及摩擦性能的影响

目的改善石墨烯与铜铁基摩擦材料的结合方式,探究不同含量的石墨烯对铜铁基摩擦材料组织结构的影响,研究加入不同含量石墨烯时摩擦材料的摩擦性能和摩擦机理。方法采用粉末冶金冷压法制备铜铁基摩擦材料,利用SEM、XRD等分析方法和手段,探究不同含量石墨烯对摩擦材料的组织结构、综合力学性能和摩擦性能的影响规律,确定最佳工艺参数。结果在铜铁基摩擦材料中加入石墨烯时,其密度和抗压强度随着石墨烯含量的增加呈下降趋势,硬度呈先上升后降低的趋势。在相同转速下,随着石墨烯含量的增加,其摩擦材料的摩擦因数呈下降趋势,磨损率呈现先下降后上升的趋势。在石墨烯的质量分数为0.5%时,摩擦材料的摩擦率最小,为2.52×10^(-9)mm^(3)/(N·m),此时摩擦材料的磨损机理为黏着磨损及少量磨粒磨损。结论在铜铁基摩擦材料中,石墨烯作为润滑组元,与基体的结合性能表现优异,对比石墨烯对铜铁基摩擦材料的影响规律可知,在石墨烯的质量分数为0.5%时,摩擦材料的性能最佳。