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CLINICAL STUDY ON SERUM COPPER AND ZINC LEVELS AND COPPER/ZINC RATIO IN MALIGNANT LYMPHOMA
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作者 吴海鹰 俞鲁谊 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第3期53-56,共4页
173 simultaneous determinations of serum copper levels (SCL), serum zinc levels (SZL) and copper/zinc ratio (CZR) were made by atomic absorption spectrophotometry in 51 previously untreated lymphoma patients. SCL and ... 173 simultaneous determinations of serum copper levels (SCL), serum zinc levels (SZL) and copper/zinc ratio (CZR) were made by atomic absorption spectrophotometry in 51 previously untreated lymphoma patients. SCL and CZR were significantly higher in patients before treatment (mean value 22.97 μmol/L, 1.55, respectively) and in those who did not reach complete remission (mean 21.21 μmol/L, 1.36) as compared with the patients in complete remission (mean 16.36 μmol/L, 1.06) or normal controls (mean 15.67 μmol/L, 0.98). The mean value of SCL and CZR of patients in complete remission did not differ significantly from those of normal controls. Patients in stages HI and IV had higher SCL and CZR (mean 25.15 μmol/L, 1.79) than those in stage Ⅰ and Ⅱ (mean 19.30 μmol/L, 1.16). No significant difference in SZL was observed between the patient groups and normal controls. Thus, SCL and CZR may be used as prognostic indicators for monitoring disease activity and response to therapy in malignant lymphoma. 展开更多
关键词 SCL CLINICAL STUDY ON SERUM copper AND zinc LEVELS AND copper/zinc ratio IN MALIGNANT LYMPHOMA NHL
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Serum Zinc and Copper Level in Juvenile Idiopathic Arthritis (JIA) Patients and Its Correlation with Disease Duration-A Tertiary Hospital Study
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作者 Mohammad Imnul Islam Mujammel Haque +4 位作者 Tanzida Sultana Mousumi Ahmed Mohammed Mahbubul Islam Kamrul Laila Manik Kumar Talukder 《Open Journal of Rheumatology and Autoimmune Diseases》 2024年第2期60-68,共9页
Background: Juvenile Idiopathic Arthritis (JIA) is the most prevalent rheumatic disease in children. It is associated with abnormal levels of serum zinc (Zn) and copper (Cu) as during inflammation serum copper concent... Background: Juvenile Idiopathic Arthritis (JIA) is the most prevalent rheumatic disease in children. It is associated with abnormal levels of serum zinc (Zn) and copper (Cu) as during inflammation serum copper concentration increases and zinc decreases. Objective: To assess the serum Zn and Cu levels in different sub-types of JIA patients and their correlation with the disease duration. Methods: This cross-sectional study was conducted over twelve months at the Pediatric Rheumatology Division, Department of Paediatrics, Bangabandhu Sheikh Mujib Medical University. Sixty-nine JIA cases that fulfilled the International League of Association for Rheumatology (ILAR) criteria were taken as cases and age and sex-matched healthy children were considered as controls. The serum Zn and Cu tests were done using the spectrophotometric method with INDIKO PLUS Drug Analyzer. Data were recorded in a pre-designed questionnaire. Data were checked, verified and analyzed manually where continuous variables were analyzed using unpaired t-test and categorical variables using the ANOVA test. Pearson’s correlation coefficient test was used to see the correlation of serum zinc and copper levels with disease duration. Results: Boys were predominant in both case and control groups, with the majority within the 10 to 16-year-age group. Enthesitis-related arthritis (ERA) was the most common subtype followed by sJIA, Oligo JIA, Poly JIA (RF-) and unclassified subtypes. Disease duration was found less than 12 months in 30.4% of JIA patients. Serum analysis revealed a statistically significant reduction in mean zinc levels and increased copper levels in JIA patients compared to controls. This study observed a negative correlation between serum zinc levels and disease duration, whereas serum copper levels exhibited a positive correlation with disease duration. Conclusion: In conclusion, this study revealed that JIA patients exhibit alterations in serum zinc and copper levels. Serum copper levels showed a positive correlation and serum zinc levels showed a negative correlation with the duration of the disease. 展开更多
关键词 copper Juvenile Idiopathic Arthritis zinc
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Concentrations of copper, zinc and manganese in Tree Sparrow (Passer montanus) at Jixi, Heilongjiang Province, China 被引量:1
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作者 Gong Qian-qian Jin Zhi-min Zou Hong-fei 《Journal of Forestry Research》 CAS CSCD 2012年第2期319-322,共4页
Concentrations of copper (Cu), zinc (Zn) and manganese (Mn) were measured in four tissues of Tree Sparrow (Passer montanus) from three sites in Heilongjiang province, China, during four seasons. Among the four... Concentrations of copper (Cu), zinc (Zn) and manganese (Mn) were measured in four tissues of Tree Sparrow (Passer montanus) from three sites in Heilongjiang province, China, during four seasons. Among the four measured tissues (primary feathers, liver, heart, and pectoral muscle), the highest concentrations were found in feathers (Zn) or liver (Cu and Mn), and the lowest concentrations were in muscle, except Cu. For Mn, mean concentrations of the birds from the three study sites were, in decreasing order: Didao mining area (DMA) 〉 urban district of Jixi (UDJ) 〉 Phoenix Mountain national nature reserve (PMR, the reference site), but not for Zn and Cu. There were significant differences between metal concentrations at the three sites, but differences were not significant for Mn (in muscle and feathers) and Cu (in feathers). For most elements, the mean concentrations were greatest in summer. 展开更多
关键词 copper MANGANESE mining tree sparrow zinc Jixi
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Selective separation of copper and cadmium from zinc solutions by low current density electrolysis 被引量:4
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作者 杨卜 王成彦 +3 位作者 李敦钫 尹飞 陈永强 王念卫 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第3期533-536,共4页
Copper and cadmium ions were selectively separated from zinc sulphate aqueous solution or zinc ammonia/ammonium sulphate aqueous solution by low current density electrolysis.It was shown that the concentration of cadm... Copper and cadmium ions were selectively separated from zinc sulphate aqueous solution or zinc ammonia/ammonium sulphate aqueous solution by low current density electrolysis.It was shown that the concentration of cadmium ion in zinc sulphate solution decreased from 4.56 g/L to 0.18 g/L in an electrolysis time of 8.5 h,whilst it decreased from 5.16 g/L to lower than 0.005 g/L in zinc ammonia/ammonium sulphate aqueous solution.On the other hand,the deposition rate of copper was so low that it was difficult to separate copper and cadmium ions from the zinc ammonia/ammonium sulphate aqueous solution during electrolysis.But copper ion could be decreased to 0.002 g/L in this solution through solvent extraction by using kerosene diluted LIX984N as extractant.Therefore,it is favorable to recover cadmium ion from the zinc ammonia/ammonium sulphate solution by electrolysis after solvent extraction of copper. 展开更多
关键词 硫酸锌溶液 选择性分离 电流密度 电解铜 镉离子 LIX984N 溶剂萃取 硫酸铵
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Annual changes of iron, manganese, zinc and copper concentrations in both types of citrus fruit 被引量:2
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作者 XIAO Jia-Xin PENG Shu-An 《广西植物》 CAS CSCD 北大核心 2008年第2期237-241,共5页
关键词 柑橘 果实 含量测定 年周期变化 结实类型
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Pig Compost Use on Zinc and Copper Concentrations in Soils and Corn Plants
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作者 Juan Hirzel Ingrid Walter 《American Journal of Plant Sciences》 2015年第4期524-536,共13页
The use of pig compost (PC) in agricultural land has increased in Chile in the last years. This organic amendment is a valuable nutritional source for crops, but its applying must be done in a controlled manner since ... The use of pig compost (PC) in agricultural land has increased in Chile in the last years. This organic amendment is a valuable nutritional source for crops, but its applying must be done in a controlled manner since it exhibited high copper (Cu) and zinc (Zn) concentrations. A short-term field experiment was conducted out to study the effects of increasing PC rates on the production and quality corn crop in two soils located at south central Chile. Five treatments were evaluated: control without fertilization (C), conventional fertilization (CF) (350 kg N ha-1), and three increasing PC rates (15.33, 30.65, and 61.31 Mg&middotha-1, corresponding to 350, 700, and 1400 kg N ha-1, respectively) in a split plot design with four replicates. The overall results indicated that dry matter production, grain yield, and plant Zn and Cu concentrations were similar among fertilization sources and rates. Extractable soil Zn concentration exhibited a rate-related increase of PC in both locations, while Cu concentration exhibited this behavior only at the soil located in Chillan. Nevertheless, the values obtained were below of those considered phytotoxic levels. Therefore, the contribution of Zn and Cu through PC applying at different rates to the soils studied showed a slight affect in soil extractable Zn and Cu values without negatively effects on quantity and quality corn crop. The organic amendment applied can be a good and cheaper substitute to conventional fertilization, although further monitoring of Zn and Cu soil levels should be carried out to avoid any environmental risk. 展开更多
关键词 PIG COMPOST CORN Crop zinc and copper in Plant Extractable Soil zinc and copper
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Competitive Complexation of Copper and Zinc by Sequentially Extracted Humic Substances from Manure Compost 被引量:4
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作者 LIU Shuai WANG Xu-dong LU Li-lan DIAO Shi-rong ZHANG Jun-feng 《Agricultural Sciences in China》 CAS CSCD 2008年第10期1253-1259,共7页
Chicken manure with similar content of copper and zinc was changes of organic carbon and humus substance complexed chosen to conduct a composting experiment to investigate the copper (HS-Cu) and zinc (HS-Zn), whic... Chicken manure with similar content of copper and zinc was changes of organic carbon and humus substance complexed chosen to conduct a composting experiment to investigate the copper (HS-Cu) and zinc (HS-Zn), which were extracted by water (H2O), sodium hydroxide (NaOH), and sodium pyrophate-NaOH mixture (Na4P2O7-NaOH), sequentially. Distributions of copper and zinc in fulvic acids (FA) and humic acids (HA) in the three extracts were studied. During manure composting, the concentrations of copper and zinc increased from about 500 mg kg^-1 in the raw material to 1 100 mg kg^-1 in the final products. HS-Cu in H2O, NaOH, and Na4P2O7-NaOH extracts occupied 6.7, 26.7, and 19% averagely of total copper and HS-Zn represented 2.7, 13.7, and 17% averagely of total zinc in compost, respectively. In water extracts, both HA and FA mainly complexed with Cu and the mole ratio of Cu to Zn was 2.8 in HA fractions and was 2.6 in FA fractions, respectively. HA mainly complexed with copper, so that the ratios of HA-Cu to HA-Zn averaged 3.4 in NaOH extracts. FA had a similar potential to complex with copper and zinc, so that the ratio of FA-Cu to FA-Zn was close to 1. In Na4P2O7-NaOH extracts, HA or FA had a similar potential to complex with copper and zinc. The ratio of HS-Cu to HS-Zn was close to 1. With manure composting, Na4P2O7-NaOH extractable HS-Zn increased to a level as high as HS-Cu. This indicated that more and more stable complexes of HS-Zn were formed in the late decomposition period. The competition between copper and zinc to be complexed with humic substance became weaker and weaker with the decomposition process. 展开更多
关键词 MANURE copper and zinc decomposition process humic substance sequential extraction
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Use of ionic liquid in leaching process of brass wastes for copper and zinc recovery 被引量:2
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作者 Ayfer Kilicarslan Muhlis Nezihi Saridede +1 位作者 Srecko Stopic Bernd Friedrich 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2014年第2期138-143,共6页
Brass ash from the industrial brass manufacturer in Turkey was leached using the solutions of ionic liquid (IL) 1-butyl-3-methyl-imi-dazolium hydrogen sulfate ([bmim]HSO4) at ambient pressure in the presence of hy... Brass ash from the industrial brass manufacturer in Turkey was leached using the solutions of ionic liquid (IL) 1-butyl-3-methyl-imi-dazolium hydrogen sulfate ([bmim]HSO4) at ambient pressure in the presence of hydrogen peroxide (H2O2) and potassium peroxymonosulfate (oxone) as the oxidants. Parameters affecting leaching efficiency, such as dissolution time, IL concentration, and oxidizing agent addition, were investigated. The results show that [bmim]HSO4 is an efficient IL for the brass ash leaching, providing the dissolution efficiencies of 99%for Zn and 24.82%for Cu at a concentration of 50vol%[bmim]HSO4 in the aqueous solution without any oxidant. However, more than 99%of zinc and 82%of copper are leached by the addition of 50vol%H2O2 to the [bmim]HSO4 solution. Nevertheless, the oxone does not show the promising oxidant behavior in leaching using [bmim]HSO4. 展开更多
关键词 leaching recovery copper zinc ionic liquids OXIDANTS
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Copper and Zinc Enrichment in Different Size Fractions of Organic Matter from Polluted Soils 被引量:49
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作者 ZHANGMing-Kui KEZi-Xia 《Pedosphere》 SCIE CAS CSCD 2004年第1期27-36,共10页
Bioavailability of heavy metals in soil organic matter depends on its components. Characterization of heavy metal distributions in different fractions of soil organic matter is needed for better understanding of the f... Bioavailability of heavy metals in soil organic matter depends on its components. Characterization of heavy metal distributions in different fractions of soil organic matter is needed for better understanding of the fate of heavy metals. This study investigated the accumulation and partitioning of copper and zinc among different size particulate organic matter (POM) fractions in polluted soils from a former iron ore processing site in western Shaoxing County, Zhejiang Province. Physical fractionations were carried out to separate soil primary particles according to their size and density. Copper and Zn had a heterogeneous distribution among soil particle fractions. Copper and Zn were significantly (p < 0.05) enriched in the POM fractions. > 0.05 mm POM and < 0.05 mm fine soil fractions were mainly responsible for Cu and Zn retention in soils. The POM fraction contained up to 1 322 mg Cu kg-1 and 1 115 mg Zn kg-1 and the fine soil fraction contained up to 422 mg Cu kg-1 and 537 mg Zn kg-1. The total POM fraction was responsible for 15.8%-41.2% and 12.2%-31.7% of the total amount of Cu and Zn, respectively, in the polluted soils. The percentages of Cu and Zn associated with organic matter in < 0.05 mm fine soil fractions for the polluted soils ranged from 14.1% to 24.5%, and 5.4% to 15.8%, respectively. Accumulation of soil organic matter could increase enrichment of Gu (or Zn) in the POM fractions. Also, Cu provided a greater enrichment in the POM fractions than Zn. 展开更多
关键词 重金属 土壤成分 堆积物 土壤污染
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Recovery of nickel,cobalt,copper and zinc in sulphate and chloride solutions using synergistic solvent extraction 被引量:10
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作者 chu yong cheng keith r.barnard +2 位作者 wensheng zhang zhaowu zhu yoko pranolo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第2期237-248,共12页
A number of synergistic solvent extraction(SSX) systems have been developed to recover nickel,cobalt,zinc and copper from sulphuric and chloride leach solutions by the solvent extraction team of CSIRO,Australia.These ... A number of synergistic solvent extraction(SSX) systems have been developed to recover nickel,cobalt,zinc and copper from sulphuric and chloride leach solutions by the solvent extraction team of CSIRO,Australia.These include(1) Versatic 10/CLX50 system for the separation of Ni from Ca in sulphate solutions,(2) Versatic 10/4PC system for the separation of Ni and Co from Mn/Mg/Ca in sulphate solutions,(3) Cyanex 471X/HRJ-4277 system for the separation of Zn from Cd in sulphate solutions,(4) Versatic 10/LIX63 system for the separation of Co from Mn/Mg/Ca in sulphate solutions,(5) Versatic 10/LIX63/TBP system for separation of Ni and Co from Mn/Mg/Ca in sulphate solutions,(6) Versatic 10/LIX63 system for the separation of cobalt from nickel in sulphate solutions by difference in kinetics,(7) Cyanex 272/LIX84 system for the separation of Cu/Fe/Zn from Ni/Co in sulphate solutions,(8) Versatic 10/LIX63/TBP system to recover Cu/Ni from strong chloride solutions,and(9) Versatic10/LIX63 system to separate Cu from Fe in strong chloride solutions.The synergistic effect on metal separation and efficiency is presented and possible industrial applications are demonstrated.The chemical stability of selected SSX systems is also reported. 展开更多
关键词 硫酸盐溶液 镍钴分离 氯化物溶液 协同萃取 铜/镍 溶剂萃取法 锌镉 回收
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Extractability and Mobility of Copper and Zinc Accumulated in Sandy Soils 被引量:6
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作者 ZHANG Ming-Kui HE Zhen-Li +1 位作者 D. V. CALVERT P. J. STOFFELLA 《Pedosphere》 SCIE CAS CSCD 2006年第1期43-49,共7页
Extractability and mobility of Cu and Zn and their relationships with 1) accumulation of Cu and Zn and 2) soil pH were studied in three sandy soils (Wabasso, Ankona, and Winder) from commercial citrus groves in Florid... Extractability and mobility of Cu and Zn and their relationships with 1) accumulation of Cu and Zn and 2) soil pH were studied in three sandy soils (Wabasso, Ankona, and Winder) from commercial citrus groves in Florida, USA. The soils, with a broad range of Cu and Zn concentrations, were fractionated by a modified procedure of Amacher, while Cu and Zn mobility were evaluated using column leaching. The extractability of Cu and Zn increased with decreasing soil pH. Also with increasing total soil Cu and Zn for extractable Cu in the Wabasso sand a threshold level, where the metal extraction rate increased, was noted at 100 mg kg-1, whereas for extractable Zn in the Wabasso sand the threshold level was found at 60 mg kg-1 and in the Ankona sand at 120 mg kg-1. These results suggested that the release potential of Cu and Zn was greater in the Wabasso sand than in the Ankona sand. The column leaching experiment showed that at total soil Cu or Zn concentrations < 100 mg kg-1 all leachates had low Cu and Zn concentrations. However at total concentrations > 200 mg kg-1 for Cu and > 150 mg kg-1 for Zn with decreasing soil pH, the concentrations of both Cu and Zn in the leachates increased exponentially. Also in these sandy soils soluble Cu and Zn mainly originated from the exchangeable fractions, and pH was a key factor controlling Cu and Zn extractability and mobility. 展开更多
关键词 砂土 萃取行为 迁移行为
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Uncertainty in Detecting Copper and Zinc Contents in Maize Flour by Flame Atomic Absorption Spectrometry with Wet Digestion Method 被引量:1
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作者 Jianghua SHAN 《Agricultural Biotechnology》 CAS 2016年第1期1-4,7,共5页
[ Objective] This study aimed to evaluate the uncertainty in detecting copper and zinc contents in maize flour by flame atomic absorption spectrometry. [ Method] Combined with the actual inspection experience, the unc... [ Objective] This study aimed to evaluate the uncertainty in detecting copper and zinc contents in maize flour by flame atomic absorption spectrometry. [ Method] Combined with the actual inspection experience, the uncertainty in detecting copper and zinc contents in maize flour by tame atomic absorption spec- trometry was evaluated to establish the mathematical model. The uncertainty sources in the experimental process were investigated to analyze several components af- fecting the uncertainty in sample detection, including sample weighing, standard material transfer, solution dilution and volume setting, curve fitting, and repeat- ability of measurement instruments. [ Result] Standard curve fitting and repeatability test were two major factors that significantly affected the combined standard uncertainty. However, in the actual detection process, standard curve calibration and repeated detection procedures should be controlled strictly. Finally, the ex- panded uncertainty of copper and zinc contents in maize flour was ( 1.38 ± 0.08) mg/kg and ( 10.20 ± 1.20) mg/kg, respectively. [ Conclusion] This study provided reference for improving the accuracy and reliability of the detection method. 展开更多
关键词 Atomic absorption spectrometry UNCERTAINTY Maize flour copper zinc
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Leaching of Copper and Zinc in a Garden Soil Receiving Poultry and Livestock Manures from Intensive Farming 被引量:5
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作者 HAO Xiu-Zhen ZHOU Dong-Mei +1 位作者 CHEN Huai-Man DONG Yuan-Hua 《Pedosphere》 SCIE CAS CSCD 2008年第1期69-76,共8页
The leaching characteristics of a garden soil may be greatly affected by application of poultry and livestock manures from intensive farming.Packed soil columns of a garden soil (CK) and the soils after respectively r... The leaching characteristics of a garden soil may be greatly affected by application of poultry and livestock manures from intensive farming.Packed soil columns of a garden soil (CK) and the soils after respectively receiving 2% pig manure (PM),chicken manure (CM),and commercial organic manure (OM) were leached with 0.05 mol L^(-1) Ca(NO_3)_2 and 0.01 mol L^(-1) EDTA solutions.The leachate EC (electric conductivity) values gradually increased at the beginning and then reached a stable value when the soil columns were leached with 0.05 mol L^(-1) Ca(NO_3)_2 solution.The leachate EC values showed a peak-shape when leached with 0.01 mol L^(-1) EDTA solution.In all the soil columns,the pH values of the leachates decreased with increase of displacement volumes when the Ca(NO_3)_2 solution was used.The total amounts of Cu and Zn eluted from the four soil columns were significantly correlated with the extracted soil Cu and Zn concentrations by 1.0 mol L^(-1) NH_4NO_3,but were not correlated with the leachate dissolved organic carbon (DOC) contents.The Zn concentration in the leachate of the PM-treated soil column with 0.05 mol L^(-1) Ca(NO_3)_2 solution was above the Quality StandardⅢfor Ground Water of China (GB/T 14848-93,Zn<1.0 mg L^(-1)).When compared with 0.05 mol L^(-1) Ca(NO_3)_2,the EDTA solution significantly accelerated Cu and Zn elutions in the manure-treated columns.This suggested that applying poultry and livestock manures from intensive farming to farmland might pose a threat to the groundwater quality. 展开更多
关键词 肥料 浸润度 锌元素 铜元素 花园土壤
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Solvent extraction of copper and zinc from bioleaching solutions with LIX984 and D2EHPA 被引量:6
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作者 蓝卓越 胡岳华 +1 位作者 柳建设 王军 《Journal of Central South University of Technology》 2005年第1期45-49,共5页
The solvent extraction of copper and zinc from the bioleaching solutions of low-grade sulfide ores with LIX984 and D2EHPA was investigated. The influences of extractant content, aqueous pH value, phase ratio and (equi... The solvent extraction of copper and zinc from the bioleaching solutions of low-grade sulfide ores with LIX984 and D2EHPA was investigated. The influences of extractant content, aqueous pH value, phase ratio and (equilibration) time on metals extraction were studied. The results show that LIX984 has a higher selectivity for copper than for iron, zinc and other metals, and has the copper extraction rate above 97%, while the zinc and iron extraction rate is less than 1.6% respectively. Zinc extraction is carried out following the copper extraction from the raffinate. The zinc extraction with di(2-ethylhexyl) phosphoric acid(D2EHPA) is low due to its poor cation exchange. A sodium salt of D2EHPA is used and the zinc extraction rate is enhanced to above 98%. Though iron (Ⅲ) is strongly extracted before the extraction of zinc by D2EHPA, it is difficult to strip iron from the organic phase by sulfuric acid. The zinc stripping rate is above 99% with 100g/L sulfuric acid, while that of iron is 0.16%. Hence, the separation of zinc from iron can be achieved by the selective stripping. 展开更多
关键词 溶剂萃取 生物滤化 LIX984 D2EHPA
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Zinc and Copper Status in Urban Thai PregnantWomen and Their Pregnancy Outcome 被引量:1
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作者 SRIWATANA SONGCHITSOMBOON, D. Sc. SURAT KOMINDR,MD. WINIT PHUAPRADIT, MD.,MPH., AND JINTANA SIRIVARASAI, M. Sc.(Research Center, Department of Medicine, and Department of Obstetric and Gynecology, Faculty of Medicine, Ramathibodi Hospital, Mahidol Univer 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1998年第2期156-164,共9页
Zinc and copper intakes and serum concentrations were determined at the 32th and 36th week of pregnancy in 96 healthy Thai women attending a prenatal clinic. Dietary data from 3-day food records revealed that the mean... Zinc and copper intakes and serum concentrations were determined at the 32th and 36th week of pregnancy in 96 healthy Thai women attending a prenatal clinic. Dietary data from 3-day food records revealed that the mean dietary zinc and copper intakes in Thai pregnant women were 6. 9 and 1. 7mg/d (equivalent to 34 and 69% of Thai RDA), respectively. Fifty-five percent of zinc intake was from animal origin, whereas 59% of copper intake was from plant origin.The infants of the 64 women who were in the study until delivery, were all normal.Most (>96%) of the maternal serum zinc and copper concentrations were within normal ranges. Only one woman at 32th week had low serum zinc level (<6. 4μmol/L). There were no significant correlations between the maternal serum zinc or copper levels and pregnancy outcome (birth weight and birth length). In this study, although the zinc and copper intake in most Thai pregnant women (99 and 58%, respectively) were less than two-thirds of the Thai RDAs, they were not at risk of suffering from zinc and copper deficiencies as determined by serum zine and copper concentrations, abnormal parturition and abnormal pregnancy outcome. 展开更多
关键词 Am In zinc and copper Status in Urban Thai PregnantWomen and Their Pregnancy Outcome
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Kinetic Study of Cementation of Copper on Zinc Metal in Ethanol-Water Mixtures 被引量:1
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作者 A.A.Zaghloul G.M.EI-Subruiti and A.M.Ahmed(Chemistry Depatment, Faculty of Science, Alexandria University Alexandria, Egypt) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1996年第1期41-45,共5页
The cementation reaction of copper on zinc metal in solutions of different concentrations ofcopper sulphate, at 25℃, has been studied and it is found to be a first order reaction. Moreover,the rates of this reaction ... The cementation reaction of copper on zinc metal in solutions of different concentrations ofcopper sulphate, at 25℃, has been studied and it is found to be a first order reaction. Moreover,the rates of this reaction at 0.15 mol'L-1 copper sulphate solution have been measured in a varietyof ethanol-water media at temperatures from 20℃ to 40℃. The correlation between the masstransfer coefficient and the dielectric constant has been investigated. Also, the thermodynamicparameters of activation have been calculated. The isokinetic relationship reveals the existenceof compensation effect, where the solute-solvent interactions play an important role. 展开更多
关键词 FIGURE Kinetic Study of Cementation of copper on zinc Metal in Ethanol-Water Mixtures
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Removal of Cadmium, Copper, and Zinc from Aqueous Solution by Activated Carbon Impregnated with 8-Hydroxyquinoline 被引量:2
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作者 T. Garoma S. Shah B. Badriyha 《Journal of Environmental Science and Engineering》 2010年第5期14-21,共8页
关键词 浸渍活性炭 羟基喹啉 水溶液 除镉 吸附能力 分配系数
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Interaction of ions in water system containing copper-zinc alloy for boiler energy saving 被引量:2
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作者 MING Xing LIANG Jinsheng OU Xiuqin TANG Qingguo DING Yan 《Rare Metals》 SCIE EI CAS CSCD 2006年第z1期405-410,共6页
Copper-zinc alloy element for boiler energy saving was put in the intake of simulated boiler system to investigate the interaction and transfer of ions in water system both theoretically and experimentally. The foulin... Copper-zinc alloy element for boiler energy saving was put in the intake of simulated boiler system to investigate the interaction and transfer of ions in water system both theoretically and experimentally. The fouling was analyzed by scanning electron microscopy (SEM) and energy dispersive X-ray detector (EDX). The results show that the transfer of calcium and magnesium ions in heat-transfer-surface-water system is affected by zinc ions dissolved from the alloy because of primary battery reaction. Some calcium ions of calcium carbonate crystal are replaced by zinc ions, the growth of aragonite crystal nucleus is retarded, and the transition of calcium carbonate from aragonite to calcite is hampered. 展开更多
关键词 copper-zinc alloy calcium carbonate FOULING energy saving BOILER water treatment interaction of ions
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Release behavior of copper and zinc from sandy soils
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作者 ZHANGMing-kui XIAYi-ping 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第4期566-571,共6页
The concentrations and chemical forms of copper(Cu) and zinc(Zn) in surface soils directly influence the movement of Cu and Zn. In this study, thirteen sandy soil samples with a wide range of total Cu and Zn concentra... The concentrations and chemical forms of copper(Cu) and zinc(Zn) in surface soils directly influence the movement of Cu and Zn. In this study, thirteen sandy soil samples with a wide range of total Cu and Zn concentrations were collected for evaluating the relationships between Cu and Zn release and extraction time, ratio of soil to water, pH and electrolyte types. The results indicated that Cu released in batch extraction that represents long-term leaching was mainly from exchangeable, and carbonate bound Cu fractions, and Zn released in the batch extraction was mainly from its carbonate bound fraction. However, the Cu and Zn leached from the soils using the column leaching that represents short-term leaching were mainly from their exchangeable fractions. Soil column leaching at different pH values indicated that the amounts of leached Zn and Cu were greatly affected by pH. The Cu and Zn release experiments with varying extraction times and ratio of soil to water suggest that long-term water-logging in the soils after rain may increase contact time of the soils with water and the release of Cu and Zn to water from the soils, and total amounts of Cu or Zn released from the soils increase, but the Cu or Zn concentration in the surface runoff decrease with increasing rainfall intensity. The increased Ca concentration in soil solution increased stability of organic matter-mineral complexes and might decrease the dissolution of organic matter, and thus decreased the release of Cu-binding component of organic matter. However, high concentration of Na in the soil solution increased the dispersion of the organic matter-mineral complexes and increased dissolution of organic matter and the release of Cu from the soils. 展开更多
关键词 release behavior copper zinc sandy soil
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THE STUDY ON THE CHANGES OF ZINC, COPPER, CALCIUM AND MAGNESIUM IN PLASMA AND ERYTHROCYTES DURING CARDIOPULMONARY BYPASS
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作者 耿希刚 李兆志 +1 位作者 李明 师桃 《Journal of Pharmaceutical Analysis》 SCIE CAS 2004年第1期71-74,共4页
Objective To study the changes and their influence factors involved of zinc, copper, calcium and magnesium in plasma and erythrocytes during cardiopulmonary bypass(CPB). Methods Zinc, copper, calcium and magnesium v... Objective To study the changes and their influence factors involved of zinc, copper, calcium and magnesium in plasma and erythrocytes during cardiopulmonary bypass(CPB). Methods Zinc, copper, calcium and magnesium values in plasma and erythrocytes were measured by atomic absorption spectrophotometer during CPB. Results Zinc and copper levels in plasma were significantly elevated above preinduction level before perfusion, but calcium and magnesium levels did not change significantly; zinc, copper and calcium levels in plasma were significantly below preoperation level during CPB, but magnesium level in plasma was significantly increased above preoperation; zinc level in plasma was increased to preoperation level after CPB and began to decrease again at 8 hours after CPB, copper level in plasma was increased to preoperation level at 20 hours after CPB, calcium in plasma was increased significantly from beginning to 8 hours after CPB, magnesium level in plasma was decreased to preoperation level at 8 hours afterCPB. Concentration of zinc , copper, calcium and magnesium in erythrocytes did not change significantly. Conclusion During CPB, the changes of zinc, copper, calcium and magnesium had relation to hemodilution, operative wound, carrier protein, stress and component of priming solution and cardioplegic solution, but no relation to transfer from plasma erythrocytes. The results indicate that it is beneficial to patient's recovery to supplement zinc, copper, calcium and magnesium properly by different ways during cardiac perioperation. 展开更多
关键词 cardiopulmonary bypass cardiac surgery zinc copper CALCIUM MAGNESIUM
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