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Cloning and Expressing of a Gene Encoding Cytosolic Copper/Zinc Superoxide Dismutase in the Upland Cotton
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作者 HU Gen-hai YU Shu-xun +1 位作者 FAN Shu-li SONG Mei-zhen 《Agricultural Sciences in China》 CAS CSCD 2007年第5期536-544,共9页
In this study,a gene encoding a superoxide dismutase(SOD)was cloned from senescent leaves of cotton(Gossypium hirsutum),and its expressing profile was analyzed.The gene was cloned by rapid amplification of cDNA ends(R... In this study,a gene encoding a superoxide dismutase(SOD)was cloned from senescent leaves of cotton(Gossypium hirsutum),and its expressing profile was analyzed.The gene was cloned by rapid amplification of cDNA ends(RACE)method.Northern blotting was used to show the profile of the gene expression,and the enzyme activity was mensurated by NBT deoxidization method in different growth periods.The full length of a gene of cytosolic copper/zinc superoxide dismutase(Cu/Zn-SOD)was isolated from cotton(GenBank Accession Number:DQ445093).The sequence of cDNA contained 682 bp,the opening reading frame 456 bp,and encoded polypeptide 152 amino acids with the predicted molecular mass of 15.03 kD and theoretical pI of 6.09.The amino acid sequence was similar with the other plants from 82 to 87%.Southern blotting showed that the gene had different number of copies in different cotton species.Northern blotting suggested that the gene had different expression in different tissues and development stages.The enzyme activity was the highest in peak flowering stage.The cotton cytosolic(Cu/Zn-SOD)had lower copies in the upland cotton.The copper/zinc superoxide dismutase mRNA expressing level showed regular changing in the whole development stages;it was lower in the former stages,higher in latter stages and the highest at the peak flowering stage.The curve of the copper/zinc superoxide dismutase mRNA expressing level was consistent with that of the Cu/Zn-SOD enzyme activity.The copper/zinc superoxide dismutase mRNA expressing levels of different organs showed that the gene was higher in the root,leaf,and lower in the flower. 展开更多
关键词 cotton copper/zinc superoxide dismutase GENE CLONING
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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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Uniformly dispersed zinc-copper alloy as anode preferentially deposited along Zn(002) plane for aqueous zinc ion batteries 被引量:1
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作者 Jing Zhu Longkun Wu +9 位作者 Zhi Peng Shuo Li Xudong Li Zekun Zhang Ningning Zhao Bin Li Wei Meng Ling Wang Lei Dai Zhangxing He 《Rare Metals》 2025年第9期6092-6101,共10页
Aqueous zinc ion batteries(AZIBs)have attracted widespread attention due to their unique advantages.However,the growth of dendrites on the anode and the occurrence of side reactions limits the improvement of electroch... Aqueous zinc ion batteries(AZIBs)have attracted widespread attention due to their unique advantages.However,the growth of dendrites on the anode and the occurrence of side reactions limits the improvement of electrochemical performance of AZIBs.The alloying of zinc anode effectively alleviates above problems,which is beneficial to the long-term cycle performance of AZIBs.In this study,zinc-copper alloy anode(Cu@Zn)was synthesized by melting method.The method is not only simple and easy to operate,but also can make the synthesized anode Cu element uniform distribution and improve the corrosion resistance of the anode.At the same time,the Cu@Zn surface reconstructed has a large proportion of Zn(002)crystal surface exposure,with the zinc affinity of Cu.Both of them can induce the uniform deposition of Zn2+ions along the Zn(002)crystal plane,further inhibiting the growth of dendrite.The Cu@Zn//Cu@Zn symmetrical batteries can cycle more than 1000 times at current densities of 0.3 and 1.2 mA cm^(-2),and maintain a relatively low hysteresis voltage.And the discharge capacity retention rate of Cu@Zn//MnO_(2)maintains 84.64%at 2.0 A g^(-1)after 1000 cycles.This study provides a new methodological reference for the development of advanced AZIBs anodes. 展开更多
关键词 Deformationqueous zinc ion batteries zinc-copper alloy MELTING Zn(002)crystal plane
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Synergistic release of copper and lithium components in biodegradable zinc alloy for osteoimmunomodulation
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作者 Yu-Jue Zhang Zhao-Yong Lv +6 位作者 Xin Luo Hui-Fen Qiang Jia-Qi He Cai-Yao Hou Ya-Geng Li Feng-Zhen Liu Lu-Ning Wang 《Rare Metals》 2025年第2期1294-1311,共18页
Zinc(Zn)-based alloys have emerged as promising bioresorbable metals for orthopedic implants because of their favorable combination of moderate degradation rates,good mechanical properties,and biocompatibility.In addi... Zinc(Zn)-based alloys have emerged as promising bioresorbable metals for orthopedic implants because of their favorable combination of moderate degradation rates,good mechanical properties,and biocompatibility.In addition,the performance of bone implants relies heavily on their osteointegration ability,which is closely related to the immune responses triggered after implantation.In this study,two Zn-based alloys,Zn–2Cu and Zn–2Cu–0.8Li were developed,to improve the comprehensive properties of Zn implants.The introduction of copper(Cu)and lithium(Li)via alloying improved the hardness and localized corrosion resistance of Zn-based specimens.Both the Zn alloys exhibited enhanced adhesion,proliferation,and osteogenic differentiation behaviors when tested with MC3T3-E1 cells.Importantly,the immune response of RAW264.7,mediated by the two Zn alloys,with pure Zn as a control was systematically investigated.The results demonstrated that the synergistic release of Cu^(2+)and Li^(+)played a pivotal role in promoting the anti-inflammatory and osteoimmunomodulatory properties of degradable Zn.By alloying with Cu and Li,we achieved sequential and sustained ion release,resulting in the synergistic enhancement of osteoimmunomodulation through the modulation of the JAK-STAT signaling pathway.Finally,the Zn-based specimens were evaluated in vivo using rat mandibular defect models.After 8 weeks,the Zn–2Cu–0.8Li group exhibited significantly higher bone regeneration than the Zn–2Cu and pure Zn groups.These findings highlight the beneficial immune response and potential of Zn–Cu–Li alloys as novel biodegradable materials for orthopedic implants. 展开更多
关键词 zinc alloys copper and lithium OSTEOGENESIS MACROPHAGES Osteoimmunomodulation
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Effect of hydrogen sulfide on reductive leaching of chalcopyrite by copper
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作者 Xin SUN Rui LIAO +5 位作者 Zu-chao PAN Yi-sheng ZHANG Mao-xin HONG Yan-sheng ZHANG Jun WANG Guan-zhou QIU 《Transactions of Nonferrous Metals Society of China》 2026年第1期287-297,共11页
A series of leaching and electrochemical experiments were conducted to elucidate the critical role of hydrogen sulfide(H_(2)S)in copper-driven reduction of chalcopyrite.Results demonstrate that in the absence of H_(2)... A series of leaching and electrochemical experiments were conducted to elucidate the critical role of hydrogen sulfide(H_(2)S)in copper-driven reduction of chalcopyrite.Results demonstrate that in the absence of H_(2)S,metallic copper converts chalcopyrite into bornite(Cu_(5)FeS_(4)).However,the introduction of H_(2)S promotes the formation of chalcocite(Cu_(2)S)by altering the oxidation pathway of copper.Electrochemical analysis demonstrates that the presence of H₂S significantly reduces the corrosion potential of copper from 0.251 to−0.223 V(vs SHE),reaching the threshold necessary for the formation of Cu_(2)S.Nevertheless,excessive H_(2)S triggers sulfate reduction via the reaction of 8Cu+H_(2)SO_(4)+3H_(2)S=4Cu_(2)S+4H_(2)O(ΔG=−519.429 kJ/mol at 50℃),leading to inefficient copper utilization. 展开更多
关键词 chalcopyrite reduction copper hydrogen sulfide CHALCOCITE
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Effect of fluoride roasting on copper species transformation on chrysocolla surfaces and its role in enhanced sulfidation flotation
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作者 Yingqiang Ma Xin Huang +5 位作者 Yafeng Fu Zhenguo Song Sen Luo Shuanglin Zheng Feng Rao Wanzhong Yin 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期165-176,共12页
It is difficult to recover chrysocolla from sulfidation flotation which is closely related to the mineral surface composition.In this study,the effects of fluoride roasting on the surface composition of chrysocolla we... It is difficult to recover chrysocolla from sulfidation flotation which is closely related to the mineral surface composition.In this study,the effects of fluoride roasting on the surface composition of chrysocolla were investigated,its impact on sulfidation flotation was explored,and the mechanisms involved in both fluoride roasting and sulfidation flotation were discussed.With CaF_(2)as the roasting reagent,Na_(2)S·9H_(2)O as the sulfidation reagent,and sodium butyl xanthate(NaBX)as the collector,the results of the flotation experiments showed that fluoride roasting improved the floatability of chrysocolla,and the recovery rate increased from 16.87%to 82.74%.X-ray diffraction analysis revealed that after fluoride roasting,approximately all the Cu on the chrysocolla surface was exposed in the form of CuO,which could provide a basis for subsequent sulfidation flotation.The microscopy and elemental analyses revealed that large quantities of"pagoda-like"grains were observed on the sulfidation surface of the fluoride-roasted chrysocolla,indicating high crystallinity particles of copper sulfide.This suggests that the effect of sulfide formation on the chrysocolla surface was more pronounced.X-ray photoelectron spectroscopy revealed that fluoride roasting increased the relative contents of sulfur and copper on the surface and that both the Cu~+and polysulfide fractions on the surface of the minerals increased.This enhances the effect of sulfidation,which is conducive to flotation recovery.Therefore,fluoride roasting improved the effect of copper species transformation and sulfidation on the surface of chysocolla,promoted the adsorption of collectors,and improved the recovery of chrysocolla from sulfidation flotation. 展开更多
关键词 sulfidation flotation CHRYSOCOLLA fluoride roasting copper species transformation enhanced sulfidation
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Rational Electrolyte Structure Engineering for Highly Reversible Zinc Metal Anode in Aqueous Batteries
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作者 Yi Zhuang Yukai Liang +8 位作者 Wenyao Zhang Yuntong Sun Zhenxing Wang Jingyan Guan Boyuan Zhu Junjie Cui Jiahao Tang Jong‑Min Lee Junwu Zhu 《Nano-Micro Letters》 2026年第3期773-806,共34页
Aqueous zinc-ion batteries(AZIBs)have garnered considerable attention as promising post-lithium energy storage technologies owing to their intrinsic safety,cost-effectiveness,and competitive gravimetric energy density... Aqueous zinc-ion batteries(AZIBs)have garnered considerable attention as promising post-lithium energy storage technologies owing to their intrinsic safety,cost-effectiveness,and competitive gravimetric energy density.However,their practical commercialization is hindered by critical challenges on the anode side,including dendrite growth and parasitic reactions at the anode/electrolyte interface.Recent studies highlight that rational electrolyte structure engineering offers an effective route to mitigate these issues and strengthen the electrochemical performance of the zinc metal anode.In this review,we systematically summarize state-of-the-art strategies for electrolyte optimization,with a particular focus on the zinc salts regulation,electrolyte additives,and the construction of novel electrolytes,while elucidating the underlying design principles.We further discuss the key structure–property relationships governing electrolyte behavior to provide guidance for the development of next-generation electrolytes.Finally,future perspectives on advanced electrolyte design are proposed.This review aims to serve as a comprehensive reference for researchers exploring high-performance electrolyte engineering in AZIBs. 展开更多
关键词 Aqueous zinc-ion batteries Electrolyte structure Anode/electrolyte interphase zinc anode
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Multiscale Theoretical Calculations Empower Robust Electric Double Layer Toward Highly Reversible Zinc Anode
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作者 Yufan Xia Zhen Luo +6 位作者 Shuang Chen Yang Xiang Gao Weng Hongge Pan Ben Bin Xu Mi Yan Yinzhu Jiang 《Nano-Micro Letters》 2026年第3期406-427,共22页
The electric double layer(EDL)at the electrochemical interface is crucial for ion transport,charge transfer,and surface reactions in aqueous rechargeable zinc batteries(ARZBs).However,Zn anodes routinely encounter per... The electric double layer(EDL)at the electrochemical interface is crucial for ion transport,charge transfer,and surface reactions in aqueous rechargeable zinc batteries(ARZBs).However,Zn anodes routinely encounter persistent dendrite growth and parasitic reactions,driven by the inhomogeneous charge distribution and water-dominated environment within the EDL.Compounding this,classical EDL theory,rooted in meanfield approximations,further fails to resolve molecular-scale interfacial dynamics under battery-operating conditions,limiting mechanistic insights.Herein,we established a multiscale theoretical calculation framework from single molecular characteristics to interfacial ion distribution,revealing the EDL’s structure and interactions between different ions and molecules,which helps us understand the parasitic processes in depth.Simulations demonstrate that water dipole and sulfate ion adsorption at the inner Helmholtz plane drives severe hydrogen evolution and by-product formation.Guided by these insights,we engineered a“water-poor and anion-expelled”EDL using 4,1’,6’-trichlorogalactosucrose(TGS)as an electrolyte additive.As a result,Zn||Zn symmetric cells with TGS exhibited stable cycling for over 4700 h under a current density of 1 mA cm^(−2),while NaV_(3)O_(8)·1.5H_(2)O-based full cells kept 90.4%of the initial specific capacity after 800 cycles at 5 A g^(−1).This work highlights the power of multiscale theoretical frameworks to unravel EDL complexities and guide high-performance ARZB design through integrated theory-experiment approaches. 展开更多
关键词 Zn anode Theoretical calculations Electric double layers Aqueous rechargeable zinc batteries
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Preparation of soybean meal peptide for chelation with copper/zinc using Aspergillus oryzae in solid-state fermentation 被引量:2
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作者 Congmiao Li Leipeng Cao +4 位作者 Tongying Liu Zhenghua Huang Yuhuan Liu Ruijuan Fan Yunpu Wang 《Food Bioscience》 SCIE 2023年第3期1181-1191,共11页
This study investigated the optimal process of solid-state fermentation(SSF)using soybean meal(SBM)as substrate by Aspergillus oryzae and proteolysis of SBM to prepare SBM-derived peptide(SBMP)for chelating with Cu(Ⅱ... This study investigated the optimal process of solid-state fermentation(SSF)using soybean meal(SBM)as substrate by Aspergillus oryzae and proteolysis of SBM to prepare SBM-derived peptide(SBMP)for chelating with Cu(Ⅱ)/Zn(Ⅱ).During the SSF of SBM,the alkaline protease activity of A.oryzae was higher than that of two other fungi,reaching maximum activity(574 U/g)at the fermentation time of 86 h,43%inoculation ratio,and liq-uid-substrate(I/S)ratio of 0.8.The SBMP yield reached a maximum value at 55℃ for 6 h hydrolysis according to the analysis of the degree of hydrolysis(DH)and total Kjeldahl nitrogen(TKN)content in hydrolysates.After ultrafiltration,the SBMP of 1-5 kDa had the best ability to chelate with Cu(Ⅱ)and Zn(Ⅱ).Moreover,the SBMP displayed a higher capacity to chelate with Zn(Ⅱ)(222.7 mg/g)than Cu(Ⅱ)(68.3 mg/g)under optimal condi-tions.Aspartic acid,glutamic acid,lysine,arginine and histidine in SBMP played a critical role at the chelating Cu(Ⅱ)/Zn(Ⅱ).UV and FTIR spectrum analysis revealed that the-COOH and-NH_(2) in SBMP were the main bioactive groups for chelating with Cu(Ⅱ)/Zn(Ⅱ).SEM showed that the surface of SBMP-Cu(Ⅱ)/Zn(Ⅱ)chelate was rough and formed spherical aggregates.These results indicated that combining SSF and proteolysis exhibited great potential for preparing SBMP-metal chelates for developing organometallic supplements. 展开更多
关键词 Soybean meal peptide Solid-state fermentation Aspergillus oryzae CHELATE copper/zinc
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Effect of Copper and Zinc on Accumulation of Vitamin E in Wheat Embryo-derived Callus
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作者 张恒 许兆棠 +3 位作者 李文谦 孙苏阳 于建疆 赵申喆 《Agricultural Science & Technology》 CAS 2011年第12期1769-1772,1783,共5页
[Objective] The aim was to study the effect of the content of copper and zinc on in medium the vitamin E accumulation in wheat embryo-dreived callus.[Method] The mathematical models were established to describe the gr... [Objective] The aim was to study the effect of the content of copper and zinc on in medium the vitamin E accumulation in wheat embryo-dreived callus.[Method] The mathematical models were established to describe the growth kinetics and the vitamin E accumulation in wheat embryo callus cells.With the aim of getting the highest accumulation of the secondary metabolite Vitamin E,the optimal combination of copper and zinc in medium was confirmed by testing.[Result] The results showed that the production of vitamin E in B5 medium reached the highest value with 2.0 mg/mL ZnSO4·7H2O and 0.1 mg/mL CuSO4·5H2O.The fitting degrees of kinetic models of vitamin E accumulation and cell growth were 97.53% and 95.60%,respectively,which indicated good nonlinear relationships.[Conclusion] Both copper and zinc could affect the accumulation of vitamin E in wheat germ callus,and Copper showed more prominent effect than Zn.Synergism existed in low copper and zinc concentration,and the inhibitive effect enhanced with the increase of the concentrations. 展开更多
关键词 Accumulation of vitamin E Wheat embryo copper and zinc Nonlinear models
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Biosorption of copper and zinc by immobilised and free algal biomass,and the effects of metal biosorption on the growth and cellular structure of Chlorella sp.and Chlamydomonas sp.isolated from rivers in Penang,Malaysia 被引量:9
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作者 W.O.Wan Maznah A.T.Al-Fawwaz Misni Surif 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第8期1386-1393,共8页
In this study, the biosorption of copper and zinc ions by Chlorella sp. and Chlamydomonas sp. isolated from local environments in Malaysia was investigated in a batch system and by microscopic analyses. Under optimal ... In this study, the biosorption of copper and zinc ions by Chlorella sp. and Chlamydomonas sp. isolated from local environments in Malaysia was investigated in a batch system and by microscopic analyses. Under optimal biosorption conditions, the biosorption capacity of Chlorella sp. for copper and zinc ions was 33.4 and 28.5 mg/g, respectively, after 6 hr of biosorption in an immobilised system. Batch experiments showed that the biosorption capacity of algal biomass immobilised in the form of sodium alginate beads was higher than that of the free biomass. Scanning electron microscopy and energy-dispersive X-ray spectroscopy analyses revealed that copper and zinc were mainly sorbed at the cell surface during biosorption. Exposure to 5 mg/L of copper and zinc affected both the chlorophyll content and cell count of the algal cells after the first 12 hr of contact time. 展开更多
关键词 green algae BIOSORPTION copper zinc immobilisation
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Use of ionic liquid in leaching process of brass wastes for copper and zinc recovery 被引量:4
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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:50
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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 itscomponents. Characterization of heavy metal distributions in different fractions of soil organicmatter is needed for better understanding of the fat... Bioavailability of heavy metals in soil organic matter depends on itscomponents. Characterization of heavy metal distributions in different fractions of soil organicmatter is needed for better understanding of the fate of heavy metals. This study investigated theaccumulation 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 particlesaccording to their size and density. Copper and Zn had a heterogeneous distribution among soilparticle 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 insoils. The POM fraction contained up to 1 322 mg Cu kg^(-1) and 1115 mg Zn kg^(-1) and the fine soilfraction contained up to 422 mg Cu kg^(-1) and 537 mg Zn kg^(-1). The total POM fraction wasresponsible for 15.8%-41.2% and 12.2%-31.7% of the total amount of Cu and Zn, respectively, in thepolluted soils. The percentages of Cu and Zn associated with organic matter in < 0.05 mm fine soilfractions 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 Cu (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 copper ENRICHMENT particulate organic matter zinc
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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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Recovery of nickel,cobalt,copper and zinc in sulphate and chloride solutions using synergistic solvent extraction 被引量:11
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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.... 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 in- clude (1) Versatic 10/CLXS0 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/LIX63fFBP system to recover Cu/Ni from strong chloride solutions, and [9) Versatic 10/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 Synergistic solvent extraction NICKEL COBALT copper zinc
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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 copper EXTRACTABILITY MOBILITY water quality 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:6
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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 respectivel... 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(NO3)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(NO3)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(NO3)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 NH4NO3, 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(NO3)2 solution was above the Quality Standard III for Ground Water of China (GB/T 14848-93, Zn 〈 1.0 mg L^-1). When compared with 0.05 mol L^-1 Ca(NO3)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 copper garden soil LEACHING MANURES zinc
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Selective separation of copper and cadmium from zinc solutions by low current density electrolysis 被引量:5
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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 copper CADMIUM zinc solution ELECTROLYSIS
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Effect of Electroacupuncture on Serum Copper, Zinc, Calcium and Magnesium Levels in the Depression Rats 被引量:5
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作者 周海虹 陆汎 +3 位作者 陈少东 周志华 韩咏竹 胡纪源 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2011年第2期112-114,共3页
Objective: To investigate effect of electroacupuncture (EA) on serum copper, zinc, calcium and magnesium levels in the rat models of depression. Methods: Forty healthy SD male rats were divided into a normal group, a ... Objective: To investigate effect of electroacupuncture (EA) on serum copper, zinc, calcium and magnesium levels in the rat models of depression. Methods: Forty healthy SD male rats were divided into a normal group, a model group, an EA group, and a maprotiline group, 10 in each with completely random. The depression models were prepared with isolated chronic unpredictable stress method in the latter three groups. EA was given at Baihui (GV 20), Yintang (EX-HN3), Fenglong (ST 40), and Taichong (LR 3) in the EA group from the second day of modeling, once every other day, 15 min each time. The maprotiline group was administered intragastrically suspension of maprotiline (10 mg/kg), once each day. After treatment for 3 weeks, serum copper and zinc levels were detected with atomic absorption method, and the serum calcium with Arsenazo Ⅲ method and magnesium with MTB method. Results: Compared with the normal group, the serum copper level (3.90±1.20mmol/L) significantly increased and the serum zinc level (2.08±0.44mmol/L) significantly decreased in the model group (P<0.05). Compared with the model group, the serum copper level (2.62±1.03mmol/L) significantly decreased, the serum zinc level (2.55±0.38mmol/L) significantly increased (P<0.05), but the serum calcium and magnesium levels did not significantly change in the EA group and the maprotiline group. Conclusion: EA can regulate the change of copper and zinc levels in the body induced by depression, which is possibly one of mechanisms of effectively improving depression symptoms. 展开更多
关键词 electroacupuncture (EA) DEPRESSION zinc copper CALCIUM MAGNESIUM rat
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Copper Delivery by the Copper Chaperone for Chloroplast and Cytosolic Copper/Zinc- Superoxide Dismutases: Regulation and Unexpected Phenotypes in an Arabidopsis Mutant 被引量:10
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作者 Christopher M. Cohu Salah E. Abdel-Ghany +5 位作者 Kathryn A. Gogolin Reynolds Alexander M. Onofrio Jared R. Bodecker Jeffrey A. Kimbrel Krishna K. Niyogi Marinus Pilon 《Molecular Plant》 SCIE CAS CSCD 2009年第6期1336-1350,共15页
Copper (Cu) is an important mineral nutrient found in chloroplasts as a cofactor associated with plastocyanin and Cu/Zn superoxide dismutase (Cu/ZnSOD). Superoxide dismutases are metallo-enzymes found in most oxyg... Copper (Cu) is an important mineral nutrient found in chloroplasts as a cofactor associated with plastocyanin and Cu/Zn superoxide dismutase (Cu/ZnSOD). Superoxide dismutases are metallo-enzymes found in most oxygenic organisms with proposed roles in reducing oxidative stress. Several recent studies in Arabidopsis have shown that microRNAs and a SQUAMOSA promoter binding protein-like7 (SPL7) transcription factor function to down-regulate the expression of many Cu-proteins, including Cu/ZnSOD in both plastids and the cytosol, during growth on low Cu. Plants contain the Cu Chaperone for SOD (CCS) that delivers Cu to Cu/ZnSODs, and, in Arabidopsis, both cytosolic and plastidic CCS versions are encoded by one gene. In this study, we demonstrate that Arabiclopsis CCS transcript levels are regulated by Cu, mediated by microRNA 398 that was not previously predicted to target CCS. The microRNA target site is conserved in CCS of Oryza sativa. The data suggest that Cu-regulated microRNAs may have more mRNA targets than was previously predicted. A CCS null mutant has no measurable SOD activity in the chloroplast and cytosol, indicating an absolute requirement for CCS. When the CCS null mutant was grown on high Cu media, it lacked both Fe superoxide dismutase (FeSOD) and Cu/ZnSOD activity. However, this did not lead to a visual phenotype and no photosynthetic deficiencies were detected, even after high light stress. These results indicate that Cu/ZnSOD is not a pivotal component of the photosynthetic anti-oxidant system during growth in laboratory conditions. 展开更多
关键词 CHLOROPLAST PHOTOSYNTHESIS copper homeostasis superoxide dismutase microRNA.
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