The soils were artificially contaminated with Pb (2500 mg kg −1 of soil) as Pb 3 (OH) 2 (CO 3) 2 (lead hydroxide carbonate) and PbS (a common lead sulfide in mining areas—galena) at a Pb concentration ratio of 1:1; Cu (500 mg kg −1 of soil) as CuCO 3 (copper carbonate); Zn (1000 mg kg −1 of soil) as ZnCO 3 (zinc carbonate) and ZnS …
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[Element] shoot :[Element] root ratios in fi eld plants (white bars) and in plants treated for 1 week with a solution containing 0.12 m M Cd, 2.7 m M Cu, 19.8 m M Pb, 42.3 m M Zn and 6.37 m M As ...
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The Pulang super-large porphyry Cu polymetallic deposit, located in the Sanjiang area of Yunnan Province, is one of the largest Cu deposits in China. This deposit hosts Cu resources of ~5 × 106 t and other ore-forming elements, such as Mo, Au, Ag, Pb, Zn, Pt and Pd. Recently, obvious hydrothermal vein-type Pb–Zn mineralization, with a …
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Cadmium is toxic to plants, easily reaching unsafe levels for animal and human consumption. A greenhouse experiment investigated the effect of foliar-applied Cd on the accumulation and distribution of Cd, Zn, Cu and Pb in wheat ( Triticum aestivum) grown in heavy metal-contaminated soil. Cadmium solutions (0, 10, 20, 30 and 40 mg L −1) were ...
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The Cu, Pb, Zn, Ag-Au deposit of Amensif is located on the northern flank of the western High Atlas. This deposit is hosted in Lower Cambrian carbonate bars and is structurally controlled by NE-SW ...
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Flocculation of colloidal size fraction for Cu, Zn, Pb, Ni and Mn was investigated on a series of mixtures with water salinities ranging from 1.5 to 9.5‰ during mixing of Haraz River with the ...
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The ore deposits mined in the study area were mostly pyrite-rich Cu–Zn–Pb sulfides bearing ore-veins. These ores are genetically linked to the hydrothermal fluid circulation active in this area during the late Tertiary, in coincidence with the waning of tectonics related to the rise of the Apennine chain. The sulfide-bearing ore-bodies ...
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The Huogeqi Cu-Pb-Zn: A case of orogenic-type base metal deposit. Studies in the past ten years have shown that the Huogeqi Cu-Pb-Zn deposit share broad …
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Soils in the vicinity of roads are recipients of contaminants from traffic emissions. In order to obtain a better understanding of the impacts of traffic on soils, a total of 225 surface soil samples were collected from an urban park (Phoenix Park, Dublin, Ireland) in a grid system. Metal (Pb, Cu and Zn) concentrations were determined using a …
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In the first step, recovery of Cu–Pb sulfide reached 45.49% with grade of 15.96% for Cu and 61.65% with grade of 7.4% for Pb. In the third step, the recovery and grade of Cu enhanced to 88% and ...
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Polymetallic veins (Pb-Zn-Cu-Ag-Au) at the world-class Bingham Canyon, Utah, porphyry Cu-Au-Mo deposit have long been recognized, but poorly understood. They are laterally zoned outward from the center of the porphyry deposit transitioning from Fe-Cu to Pb-Zn-Cu-Ag-Au mineralization. Physical and chemical characterization of these …
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However, low K d values were shown for Zn (0.17–118 L kg − 1), Ni (0.08–163 L kg − 1) and Cd (0.04–45 L kg − 1). On the basis of the K d values, the most common selectivity sequence of the metal adsorption is Pb > Cu > Zn > Ni > Cd, which it is related to the first hydrolysis equilibrium constant. Generally, the simple correlation ...
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Table 3 shows that Cu, Zn, Pb, Cd, and Cr contents are equal to 425–526, 574–1134, 321–356, 0.72–4, and 99.69–576 ppm, respectively. These levels are far above the average concentrations in the limit values (150 ppm for the Cu, 150–300 ppm for Zn, 50–300 ppm for Pb, 1–3 ppm for Cd, and 2.677 ppm for Cr) (Kouame et al. 2006). The ...
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دانشنامه. فهرست مطالب. مفهوم سنگ زنی (گرایندینگ) دقیق. مزایای سنگ زنی دقیق. انواع سنگ زنی دقیق. کاربرد سنگ زنی. اجزای اصلی دستگاه گرایندینگ. سنگ زنی دقیق یکی از مهارت های بسیار حیاتی در حوزه ماشینکاری و تولید می‌باشد. …
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In this research, flotation of copper, lead and zinc minerals from a copper oxide–sulfide ore was studied. The identification tests showed that the sample is a mixture of quartz, chalcopyrite, galena, cerussite, …
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Foliar uptake of wet- and dry-deposited Cu, Zn, and Pb played an important role in their accumulations in rice plant, contributing to 44–47%, 23–25%, and 35–37% in rice grains, respectively.
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Isotherms for the sorption of Cd, Cu, Pb, and Zn by the biochars. The red lines indicate the Freundlich fitting (CE eucalyptus forest residues, CM castor meal, PC green pericarp of coconut, SB ...
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Copper and Ag are soluble in moderately concentrated chloride brines at intermediate oxidation states, but published data suggest that Cu is strongly adsorbed on goethite and hematite at pH near 7 and temperatures of 0 degrees to 100 degrees C. Also, Pb, Zn, Co, and Ni are soluble in chloride brines, but are only present in some red-bed …
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Similarly, a trend of the maximum sorption capacities of the soil— Smax values—was described as: Cu ≈ Zn > Cd > Pb > Cr. The results of the flow tests showed that in dynamic systems, reactions were not in equilibrium, and therefore, the trend of the retardation factor was different: Zn > Cd > Pb > Cu > Cr.
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ABSTRACT: In current time the environment is heavily polluted by various toxic metals, which create a danger for all living beings. Phytoremediation can be potentially used to remediate metal-contaminated sites. A major step towards the development of phytoremediation of heavy metal impacted soils is the discovery of the heavy metal …
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0.15% Cu, 1.01% Pb, 1.22% Zn, and 9.01 g/t Ag. It comprises three ore blocks, known as Weixi, Main, and Weidong from west to east (Fig. 2a). Previous exploration revealed that Cu mineralization primarily occurred at Weixi, whereas the other two ore blocks were mainly characterized by Pb –Zn minerali-zation (Zhong et al. 2017a).
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Pb and Cu were sorbed and retained to a greater extent than Cd, Ni or Zn, which had low K d100 values. Pb was sorbed more than any other metal. Cr was generally sorbed only slightly more than Cd, Ni or Zn, but was strongly retained, with K d100 (retention) values greater than those of Pb and Cu in soils with very low CEC (<3 cmol …
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Given the proximity of residential communities to these mining residues, we investigated samples of mine waste (n = 5), urban soil (n = 6), and road dust (n = 5) with a special focus on the solid speciation of As, Cu, Pb, and Zn using a combination of methods (XRD, SEM/EDS, oxalate extractions), as well as on in vitro bioaccessibility in ...
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The pH of coprecipitate formation had little effect on the long-term solubility of Cu and Zn, whereas soluble Cd was greater in the coprecipitate formed at pH 6. Soluble percentages of metals were low at both pH 6 and 7 for Cu and Pb but averaged 1.5 to 3% for Zn and greater than 40% for Cd.
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The Weibao copper–lead–zinc skarn deposit is located in the northern East Kunlun terrane, NW China. Igneous intrusions in this deposit consist of barren diorite porphyry (U–Pb zircon age of 232.0 ± 2.0 Ma) and ore-bearing quartz diorite and pyroxene diorite (U–Pb zircon ages of 223.3 ± 1.5 and 224.6 ± 2.9 Ma, respectively). Whole-rock …
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From the Middle Ages until the beginning of the twentieth century, extensive Zn–Pb mining and smelting was carried out in East-Belgium. By lack of waste treatment techniques and sustainable management practices, metal-bearing slags and unprocessed waste were dumped in huge tailings, which still represent an important source of …
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The concentrations of Cu, Pb, and Zn do not exceed the local regulatory levels in most of the mine waste or soil samples, and in none of the road dust samples. Similar concentrations of Cu, Pb, and Zn in the mine waste and top soil did not support the hypothesis that mining is the major source of the metals in the topsoil.
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Compost decreased biological effectiveness of Zn, Cd and Pb, but increased for Cu. And R + C showed the best effects at different time. The different concentration of heavy metal (Cu, Zn, Cd and Pb) in pore water among each amendment showed that all the treatment materials decreased the movability of heavy metals, and R + C had the best …
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lead and zinc recoveries. In the first step, recovery of Cu– Pb sulfide reached 45.49% with grade of 15.96% for Cu and 61.65% with grade of 7.4% for Pb. In the third step, the recovery and grade of Cu enhanced to 88% and 18.3%, respectively. The optimization of parameters was con-ducted by software, and the supplementary tests were done
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سنگ کوارتز دارای سختی ۷ و مقاومت بالایی است و به همین دلیل طرفداران زیادی دارد. همچنین کوارتز آنتی باکتریال است و به این معنی است که هیچ گونه باکتری و میکروبی در سنگ کوارتز نمی‌تواند رشد کند.
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The genesis of the Mount Isa Cu-Pb-Zn system, northern Australia, is highly debated. Three metallogenic models have previously been proposed to explain the close spatial relationship between a world-class Cu and Pb-Zn deposit: (1) ca. 1650 Ma syngenetic Pb-Zn mineralisation that has been re-mobilised and overprinted by ca. 1520 …
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1. Introduction. Due to the rapid development of industrial and agricultural activities, heavy metals have been widely detected in the soil (Liu et al., 2020b).Owing to the persistence, high toxicity, and non-biodegradability, heavy metal contaminated soil has been considered as an increasingly severe environmental problem (Liu et al., 2018b).Cd, Pb, …
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Cd, Cu, Pb and Zn were determined in a series of environmental matrices (soils, sediments, and plants) with a wide range of major compounds, carbonates and organic matter contents. For each environmental sample, and also for some of the CRMs used in the validation step, the results obtained with the total microwave-assisted attack …
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فرایند سنگ زنی چیست و بررسی مزیت های آن: فرایند سنگ زنی یک پروسه فرسایشی است که می توان مواد اضافه ی روی قطعه کار را با عملیات سایش برداشت.
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