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铜作阳极电解实验的证实与证伪 被引量:1
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作者 钟辉生 《化学教学》 CAS 北大核心 2012年第12期54-55,共2页
利用铜作阳极,石墨为阴极的电解装置,分别对电解硫酸溶液、硫酸钠溶液和氯化钠溶液中存在的各种有争议的现象进行证实与证伪。
关键词 铜作阳极电解实验 硫酸 硫酸钠 氯化钠
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铜铁互作效应对方格星虫稚虫生长、存活、体成分及相关酶活性的影响
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作者 曾梦清 董兰芳 +6 位作者 许明珠 刘海娟 游出超 龙子扬 林立蔚 李世才 彭慧婧 《西南农业学报》 CSCD 北大核心 2023年第1期203-210,共8页
【目的】探讨微量元素铜和铁互作对方格星虫(Sipunculus nudus)稚虫生长和生理机能的影响,为开发高效的方格星虫人工配合饲料提供参考依据。【方法】采用3×3完全随机试验设计,将基础饲料分成9组,设3个水平(7.8、13.2和23.5 mg/kg)... 【目的】探讨微量元素铜和铁互作对方格星虫(Sipunculus nudus)稚虫生长和生理机能的影响,为开发高效的方格星虫人工配合饲料提供参考依据。【方法】采用3×3完全随机试验设计,将基础饲料分成9组,设3个水平(7.8、13.2和23.5 mg/kg)铜(以蛋氨酸铜形式)和3个水平(61.5、120.6和243.7 mg/kg)铁(以蛋氨酸铁形式)随机组合后添加到基础饲料中,制成9种饲料。以8100条平均体质量为(16.12±0.26)mg的方格星虫稚虫为试验对象,随机分成9组(每组3个重复),分别投喂9种试验饲料,进行为期8周的养殖试验,分析评价方格星虫稚虫的生长和生理机能指标差异。【结果】饲料中铜和铁不同添加量对方格星虫稚虫的增重率、特定生长率、存活率和虫体铜含量均具有显著影响(P<0.05,下同),对其体成分、过氧化氢酶(CAT)活性和虫体铁含量无显著影响(P>0.05);饲料中铜和铁添加量对方格星虫稚虫增重率、特定生长率、存活率和虫体铁含量具有互作效应,对其体成分、CAT活性和虫体铜含量无互作效应。当饲料铜含量为7.8 mg/kg、铁含量为120.6 mg/kg时,方格星虫稚虫的增重率和特定生长率最高;当铜含量一定时,方格星虫稚虫的增重率和特定生长率随着铁含量的增加呈先升后降变化趋势;当铜含量为7.8 mg/kg时,方格星虫稚虫的存活率主要受铁含量影响,表现为存活率随着铁含量的增加而上升。方格星虫稚虫的CAT活性主要受饲料铁含量影响,在铁含量为61.5 mg/kg的处理中活性最低,且显著低于其他处理。【结论】饲料中铜和铁的交互作用可显著影响方格星虫稚虫的生长、成活及虫体铜含量,且铁元素对方格星虫稚虫生长的影响大于铜元素。以增重率为评价标准,方格星虫稚虫饲料中的最适铜铁含量分别为7.8和120.6 mg/kg。 展开更多
关键词 方格星虫 饲料 铁互效应 生长 生理机能
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镁和铜互作对烤烟常规成分和香味物质含量的影响 被引量:5
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作者 景延秋 樊士军 +3 位作者 张豹林 袁秀秀 刘晓迪 徐敏 《河南农业大学学报》 CAS CSCD 北大核心 2015年第1期12-16,共5页
研究了烤烟叶面混合喷施不同质量分数的Mg SO4,Cu SO4溶液对烟叶常规化学成分和香味物质含量的影响,结果表明,当喷施质量分数0.2%Mg SO4和0.2%Cu SO4时,能够降低烟叶蛋白质和总氮含量,提高总糖和还原糖含量,且烤后烟叶中新植二烯含量和... 研究了烤烟叶面混合喷施不同质量分数的Mg SO4,Cu SO4溶液对烟叶常规化学成分和香味物质含量的影响,结果表明,当喷施质量分数0.2%Mg SO4和0.2%Cu SO4时,能够降低烟叶蛋白质和总氮含量,提高总糖和还原糖含量,且烤后烟叶中新植二烯含量和美拉德反应物含量在所有处理中最高,最能提高烤后烟叶香味物质总量。说明低质量分数镁和铜互作有利于烟叶常规化学成分的平衡和提高烤后烟叶香味物质总量。 展开更多
关键词 烤烟 镁互 常规化学成分 香味物质
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作册般铜鼋铭文汇释 被引量:3
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作者 张秀华 邵清石 《黑龙江教育学院学报》 2009年第1期100-101,共2页
作册般铜鼋记录了商晚期的一次射礼,公布后有诸多学者进行考释,但各家看法不一,汇集各家之言自当成为最要紧之事。
关键词 册般 汇释 射礼
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铝、镉、铜互作对不同耐铝大麦基因型糖及蛋白含量的影响
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作者 黄楠飞 郭天荣 《绍兴文理学院学报》 2007年第7期84-87,共4页
所有胁迫处理均导致耐性品种根系和叶片的蛋白质含量增加,三重复合胁迫时最高.低pH和Cu,Cd,Al复合胁迫使敏感基因型根系蛋白质含量增加而叶片蛋白质含量减少,其它胁迫结果恰好相反.Cu与Cd以及Cu,Cd,Al复合胁迫使耐性品种根系和叶片可溶... 所有胁迫处理均导致耐性品种根系和叶片的蛋白质含量增加,三重复合胁迫时最高.低pH和Cu,Cd,Al复合胁迫使敏感基因型根系蛋白质含量增加而叶片蛋白质含量减少,其它胁迫结果恰好相反.Cu与Cd以及Cu,Cd,Al复合胁迫使耐性品种根系和叶片可溶性糖含量增加,单独Al胁迫使耐性品种根系和叶片可溶性糖含量减少,但对敏感基因型的影响因器官而异.Cu与Cd复合胁迫及单独Al胁迫均使耐性品种根系还原糖含量减少而使叶片还原糖含量增加,但对敏感基因型的影响存在差异;Cu,Cd,Al复合胁迫使敏感基因型根系、叶片和耐性品种根系还原糖含量增加,却使耐性品种叶片还原糖含量减少.各种胁迫处理均使耐性品种根系和叶片总糖含量下降,但敏感品种器官和处理间结果存在显著差异. 展开更多
关键词 铝-镉- 大麦 蛋白质
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Rock-forming mechanism of Qingshanjiao intrusion in Dongguashan copper(gold) deposit, Tongling area, Anhui province, China
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作者 刘忠法 邵拥军 +1 位作者 隗含涛 汪程 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第9期2449-2461,共13页
Dongguashan deposit is a large porphyry-skarn copper(gold) deposit in Tongling ore district. The Qingshanjiao intermediate acid intrusion of Yanshanian had a direct genetic relationship with mineralization. The magm... Dongguashan deposit is a large porphyry-skarn copper(gold) deposit in Tongling ore district. The Qingshanjiao intermediate acid intrusion of Yanshanian had a direct genetic relationship with mineralization. The magma origin, rock-forming dynamic background and rock-forming process were studied, and the rock-forming mechanism of Qingshanjiao intrusion was discussed, based on geological characteristics, detailed observation of petrography and systematic investigation of petrochemistry, trace elements and REE geochemistry characteristics of Qingshanjiao intrusion. The results show that Qingshanjiao rock body belongs to high-K calc-alkaline series with higher LREE elements, Th, Rb and Sr abundance, but depleted in HREE elements, Ba, Nb and Ta. The primary magma originated from the mantle-crust mixtures which were caused by basaltic magma of mantle mixing with syenite magma of partial melting of the lower crust, and the formation environment of Qingshanjiao intrusion was emplaced in the transitional environment from compression to extension. The Harker diagram and hybrid structures of plagioclase and potassium feldspar indicate that the fractional crystallization occurred in the process of magmatic evolution. The petrochemistry, trace elements and REE geochemistry characteristics indicate that the magma was contaminated by crustal material during the rock-forming. These results suggested that the Qingshanjiao intrusion was formed by fractional crystallization and assimilation and hybridization of mantle-crust magma in the transitional environment from compression to extensional. 展开更多
关键词 Qingshanjiao intrusion geological and geochemical characteristics rock-forming and geodynamic setting magma derivation rock-forming Dongguashan copper(gold) deposit
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Interaction effects of flotation reagents for SAG mill reject of copper sulphide ore using response surface methodology 被引量:6
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作者 Ali AHMADI Mojtaba REZAEI Seyed Mohammad SADEGHIEH 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第3期792-806,共15页
Flotation reagents have a complex behaviour in the beneficiation of base minerals in clayey ores.Interaction effects of reagents on the efficiency of copper flotation for a highly clayey low-grade sulphide ore were in... Flotation reagents have a complex behaviour in the beneficiation of base minerals in clayey ores.Interaction effects of reagents on the efficiency of copper flotation for a highly clayey low-grade sulphide ore were investigated using a central composite design.Preliminary results showed that sodium-isopropyl-xanthate(SIPX)and O-isopropyl-N-ethyl-thionocarbamate(IPETC)were found to be the most efficient collectors in the presence of lime as the pH regulator.The effects of dosage of collectors(SIPX and IPETC)and the dosage of methyl-isobutyl-carbonyl(MIBC)as frother on the separation efficiency were evaluated at different pH levels.Based on the analysis of variance(ANOVA),the interaction effects of the collector−pH and collector−frother were significant for the separation efficiency.At the low level of collector dosage,increasing pH from 9 to 11 enhanced copper separation efficiency from 81%to 86%for IPETC and from 77%to 86%for SIPX.Results of ANOVA showed that the maximum copper separation efficiency(88.7%)was obtained at the dosages of 8.6 g/t SIPX,7 g/t IPETC and 20 g/t MIBC at pH 11.Finally,it was concluded that a mixture of SIPX and IPETC collectors was more suitable to treat highly clayey sulphide ores. 展开更多
关键词 FLOTATION copper sulphide REAGENT interaction effect reject ore
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Mechanism for Cu^(2+) Sorption on Palygorskite 被引量:6
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作者 CHENTian-Hu PENGShu-Chuan +2 位作者 XUHui-Fang SHIXiao-Li HUANGChuan-Hui 《Pedosphere》 SCIE CAS CSCD 2005年第3期334-340,共7页
A single-factor experiment of copper ion adsorption on pure palygorskite was carried out to understand the Cu2+ sorption of palygorskite—an important clay mineral in soil and sedimentary rock. In addition, pH of the ... A single-factor experiment of copper ion adsorption on pure palygorskite was carried out to understand the Cu2+ sorption of palygorskite—an important clay mineral in soil and sedimentary rock. In addition, pH of the solution and the surface microstructure of palygorskite were investigated before and after adsorption. The experimental results indicated that efficiency of Cu2+ removal was related to the oscillation rate of the specimen shaker, sorption time, initial pH value and the amount of adsorbent added. Palygorskite induced Cu2+ hydrolysis and interaction between copper hydroxide colloids and palygorskite surfaces, as observed with transmission electron microscopy (TEM), were the main contributions to palygorskite removal of Cu2+. This mechanism was different from adsorption at the mineral-water interface. It was proposed that surface hydrolysis of palygorskite raised the alkalinity of the palygorskite-water interface and suspension system. Thus, the induced pH of the solution was then high enough for Cu2+ hydrolysis on the mineral surface and in solution. 展开更多
关键词 copper ion PALYGORSKITE sorption mechanism transmission electron microscopy (TEM)
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Biosorption Equilibrium and Kinetics of Au(Ⅲ) and Cu(Ⅱ) on Magnetotactic Bacteria 被引量:6
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作者 宋慧平 李鑫钢 +3 位作者 孙津生 尹晓红 王艳红 武振华 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第6期847-854,共8页
Magnetotactic bacteria (MTB) as biosorbents for the adsorption of Au(Ⅲ) and Cu(Ⅱ) ions from aqueous solution have been investigated. The optimum adsorption conditions for both metal ions were the initial pH sc... Magnetotactic bacteria (MTB) as biosorbents for the adsorption of Au(Ⅲ) and Cu(Ⅱ) ions from aqueous solution have been investigated. The optimum adsorption conditions for both metal ions were the initial pH scope of 1-5.5 for Au(Ⅲ) and 2.0-4.5 for Cu(Ⅱ), room temperature, biomass concentration of 10.0g.L^-1 and sorotion du-ration more than 10 min. When the initial metal concentration were within 500mg.L^-1, the maximum biosorption capacity of 1.0g of MTB (dry mass basis) for Au(Ⅲ) and Cu(Ⅱ) were calculated as 505.2mg of Au(Ⅲ) and 493.1mg of.Cu(Ⅱ) by Langmuir model in single system, respectively. The isotherm equilibrium of Au(Ⅲ) and Cu(Ⅱ) ions in the Au-Cu binary system reflected a unique phenomenon that the adsorption of Au(Ⅲ) was rein-forced and that of Cu(Ⅱ) prohibited, compared respectively-with their performances in the single metal system.When the,concentration of-Au(Ⅲ) and Cu(Ⅱ). were below 80mg.L^-1, the waste waterafter MTB treating, wasbelow 1.0mg.L^-1, which is in conformity with Environmental Performance Standards (EPS) of Canada. Besides, all the kinetic data were fitted well to the pseudo second-order kinetic model with a high correlation coefficient (R^2〉0.999). 展开更多
关键词 magnetotactic bacteria selective adsorption adsorption equilibrium adsorption kinetics Au(Ⅲ)
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Application of Box-Behnken Design in Optimization of Allelopathic Effects of Potamogeton Pectinatus Against Microcystis Aeruginosa 被引量:5
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作者 张楠 季民 +1 位作者 潘涛 孙长虹 《Transactions of Tianjin University》 EI CAS 2014年第5期344-349,共6页
Allelopathic effects of submerged macrophytes against algae are affected by many environmental factors which can only be measured one by one by traditional methods. Box-Behnken design of response surface methodology w... Allelopathic effects of submerged macrophytes against algae are affected by many environmental factors which can only be measured one by one by traditional methods. Box-Behnken design of response surface methodology was used to optimize three environmental factors (temperature, light intensity and total dissolved solids) of allelopathic effects of Potarnogeton pectinatus against Microcystis aeruginosa at the same time. By solving the regression equation and analyzing the response surface contour plots, the optimal conditions of the relatively inhibitory rate of Microcystis aeruginosa were that the temperature was 23℃, the light intensity was 2 700 lx and the total dissolved solids were 4 415 mg/L. Under these conditions, the optimal value of relatively inhibitory rate of Microcystis aeruginosa was 81.9%. According to validation experiments, the results of analysis indicated that the experimental values fitted well with the predicted ones. 展开更多
关键词 allelopathic effects Box-Behnken design TEMPERATURE light intensity total dissolved solids
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Effects of Sorbed Phosphate on Kinetics of Cn^(2+) Sec-ondary Adsorption in Soils 被引量:3
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作者 ZHOUDAI-HUA DONGYUAN-YAN 《Pedosphere》 SCIE CAS CSCD 1995年第2期143-149,共7页
The effects of sorbed phosphate on the kinetics of Cu ̄2+ secondary adsorption on three major types ofsoils in southern and Central China were studied using the batch method and flow (or miscible displacement)techniqu... The effects of sorbed phosphate on the kinetics of Cu ̄2+ secondary adsorption on three major types ofsoils in southern and Central China were studied using the batch method and flow (or miscible displacement)techniques. Both of the methods showed that diffusions were the ratedetermining steps in the Cu ̄2+ adsorp-tion by the soils. By the flow method, the course of Cu ̄2+ adsorption kinetics consisted of two steps-sn initialrapid process and a later slow process of Cu ̄2+ adsorption; while by the batch method, the 90% of Cu ̄2+adsorption reaction was found to finish within first 1 minute. The results obtained using the flow method alsoindicated that for red soil and yellow-brown soil, Cu ̄2+ adsorptions during the initial reaction periods wererestrained when the soils sorbed phosphate, whereas the adsorption reactions were stimulated at the finaltime. For grey Chao soil, sorbed phosphate retarded the Cu ̄2+ adsorption in the whole reaction period. Theresults obtained using the batch method and flow techniques all implied that the different effects of sorbedphosphate would be attributed to its effects on Cu ̄2+ ion diffusion in soil solution. 展开更多
关键词 Cu ̄2+ secondary adsorption KINETICS SOILS sorbed phosphate
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Correlation between microstructure and corrosion and cavitation erosion behaviors of nickel aluminum bronze 被引量:1
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作者 Qi-ning SONG Hui-lin LI +5 位作者 Hao-nan ZHANG Hao HONG Nan XU Gen-yuan ZHANG Ye-feng BAO Yan-xin QIAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第9期2948-2964,共17页
The microstructure,corrosion and cavitation erosion(CE)behaviors of the as-cast and four different heat treated nickel aluminum bronzes(NABs)in 3.5 wt.%NaCl solution were investigated.The results show that after annea... The microstructure,corrosion and cavitation erosion(CE)behaviors of the as-cast and four different heat treated nickel aluminum bronzes(NABs)in 3.5 wt.%NaCl solution were investigated.The results show that after annealing,β′transformed into the eutectoid microstructure,and moreκIV precipitated fromα.Less eutectoid microstructure and moreβ′were obtained after normalizing.The quenched NAB mainly consisted ofαandβ′phases,and fine,acicularαandκphases precipitated insideβ′after subsequent aging.The largest proportion of the eutectoid microstructure,which underwent severe selective phase corrosion,was responsible for the lowest corrosion resistance of the annealed NAB.The quenched NAB possessed the most protective film and hence the highest corrosion resistance.The mechanical attack was primarily responsible for the CE damage for the as-cast,annealed and normarlized NABs.The quenched and quenched+aged NABs exhibited superior CE resistance because of the high hardness.The CE−corrosion synergy dominantly caused CE degradation,and it was largely attributed to corrosion-enhanced-CE. 展开更多
关键词 heat treatment nickel aluminum bronze CORROSION cavitation erosion synergistic effect
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Galvanic Interactions of Aluminium 3004 and ∝ Brass in Tropical Marine Atmosphere
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作者 S. Palraj G. Subramanian S. Palanichamy 《Journal of Marine Science and Application》 2014年第4期455-461,共7页
The galvanic corrosion behaviour of alumiuium 3004 - ∝ brass with different area ratios was studied in the tropical marine atmosphere at Tuticorin harbour over a period of 426 days. The area ratios, viz. AAluminiurn... The galvanic corrosion behaviour of alumiuium 3004 - ∝ brass with different area ratios was studied in the tropical marine atmosphere at Tuticorin harbour over a period of 426 days. The area ratios, viz. AAluminiurn:A∝ brass, studied were 0.125, 0.25, 0.5, 1, 2, 4 and 8. The galvanic corrosion behaviour of the metals was studied in terms of the relative increase in the corrosion rate of aluminium due to galvanic coupling with oc brass, the relative decrease in the corrosion rate of ∝ brass due to galvanic coupling with aluminium, and the susceptibility of aluminium to pitting owing to galvanic coupling with ∝ brass. The galvanic potential and galvanic current of the system were monitored. Pits of different dimensions ranging from mild etchings to perforations were experienced on the borders arid the surfaces of the interface of aluminium in contact with ∝ brass. The corrosion products resulting from galvanic corrosion were analysed using XRD and the pitting on aluminium as a result of galvanic corrosion was highlighted in terms of pit depth, size and density of pit, using a high resolution microscope. The most favourable area ratio of aluminium - ∝ brass in marine atmosphere in terms of gravimetric corrosion rate is 8:1 and the most unfavourable area ratio of aluminium - ∝ brass is 1:4. 展开更多
关键词 aluminium 3004 ∝brass galvanic corrosion corrosion products PITTING tropical marine atmosphere
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Recombinogenic Effect of the Ternary Complex of Copper(II) with Doxycycline and 1,10-Phenanthroline on Somatic Cells of Drosophila melanogaster
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作者 Jeyson Cesary Lopes Luisa Mariana Melo Guimaraes +2 位作者 Julio Cesar Nepomuceno Sandra Morelli Robson Jose de Oliveira Junior 《Journal of Pharmacy and Pharmacology》 2018年第5期531-540,共10页
In the search for new anti-tumor agents, exploiting features such as the flexibility of coordination modes of metals have become an alternative strategy for synthesizing pharmaceuticals. It has been shown that the Cu... In the search for new anti-tumor agents, exploiting features such as the flexibility of coordination modes of metals have become an alternative strategy for synthesizing pharmaceuticals. It has been shown that the CuDP (copper(II), doxycycline, and 1,10-phenanthroline) complex cleaves DNA strands by an oxidative mechanism and by intercalating the major groove, resulting in a cytotoxic action. The objective of this study was to assess the mutageinc/recombinogenic effects of the CuDP complex in vivo using the SMART (Somatic Mutation and Recombination Test) in Drosophila melanogaster. Treatments were carried out with third instar larvae at the standard cross and high bioactivation cross using three concentrations of CuDP (6.92, 13.84 or 27.67 mM). The mutagenic doxorubicin (0.4 mM) was used as a positive control and reverse osmosis water as a negative control. For each compound, marked trans-heterozygous and balanced heterozygous individuals were analyzed to determine the mutational and recombinogenic events occurring in the cells, We found that CuDP significantly increased the frequencies of mutant cells in both standard and high bioactivation crosses, mostly by induction of recombination. These data show that CuDP is a direct recombinogenic agent that is independent of bioactivation, 展开更多
关键词 COPPER recombination MUTATION Drosophila melanogaster.
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Efficient electrocatalytic reduction of carbon dioxide to ethylene on copper–antimony bimetallic alloy catalyst 被引量:6
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作者 Shuaiqiang Jia Qinggong Zhu +6 位作者 Haihong Wu Meng’en Chu Shitao Han Ruting Feng Jinghui Tu Jianxin Zhai Buxing Han 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第7期1091-1098,共8页
The exploration of efficient electrocatalysts for the reduction of CO2 to C2H4 is of significant importance but is also a challenging subject.Cu-based bimetallic catalysts are extremely promising for efficient CO2 red... The exploration of efficient electrocatalysts for the reduction of CO2 to C2H4 is of significant importance but is also a challenging subject.Cu-based bimetallic catalysts are extremely promising for efficient CO2 reduction.In this work,we synthesize a series of porous bimetallic Cu–Sb alloys with different compositions for the catalytic reduction of CO2 to C2H4.It is demonstrated that the alloy catalysts are much more efficient than the pure Cu catalyst.The performance of the alloy catalysts depended strongly on the composition.Further,the alloy with a Cu:Sb ratio of 10:1 yielded the best results;it exhibited a high C2H4 Faradaic efficiency of 49.7%and a high current density of 28.5 mA cm?2 at?1.19 V vs.a reversible hydrogen electrode(RHE)in 0.1 M KCl solution.To the best of our knowledge,the electrocatalytic reduction of CO2 to C2H4 using Cu–Sb alloys as catalysts has not been reported.The excellent performance of the porous alloy catalyst is attributed to its favorable electronic configuration,large surface area,high CO2 adsorption rate,and fast charge transfer rate. 展开更多
关键词 Carbon dioxide reduction Ethyene ELECTROCATALYST Copper-antimony bimetallic alloy Synergistic effect
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Effect of Copper Oxide Nano Particle on Seed Germination of Selected Crops
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作者 Tapan Adhikari Samaresh Kundu +2 位作者 Ashis Kumar Biswas Jagadish Chandra Tarafdar Anangi Subba Rao 《Journal of Agricultural Science and Technology(A)》 2012年第6期815-823,共9页
Nano particles are finding their way into the environment through deliberate and accidental actions, ecotoxicological properties and the risks of these nano particles have yet not been fully characterized. In this pre... Nano particles are finding their way into the environment through deliberate and accidental actions, ecotoxicological properties and the risks of these nano particles have yet not been fully characterized. In this present investigation, experiments were carried out to know the effect of Cu oxide-nano particles (〈 50 nm) on germination and growth of seeds of soybean and chickpea. In both the crops, germination was not checked up to 2,000 ppm Cu (applied through Cu oxide-nano particles), but the root growth was prevented above 500 ppm Cu. With increasing concentration of NPs, the elongation of the roots was severely inhibited as compared to that in control. In many cases root necrosis was occurred. Massive adsorption of Cu oxide-nano particles into the root system was responsible for the toxicity. A parallel experiment was also carried out to know the effect of copper sulphate solution on seed germination, above 200 ppm Cu, it restricted the germination of seeds, because of high salinity. 展开更多
关键词 Cu-nano particles SOYBEAN chickpea.
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Determination of Selected Toxic Elements in Apples from Organic Farming 被引量:1
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作者 Michaela Zeiner Iva Juranovic Cindric +1 位作者 Ivona Krizman Gerhard Stingeder 《Journal of Chemistry and Chemical Engineering》 2011年第7期577-582,共6页
Due to the elevated ecological awareness nowadays the consumption of products of organic agriculture is increasing. Organic farming means excluding the use of synthetic inputs, such as synthetic fertilizers and pestic... Due to the elevated ecological awareness nowadays the consumption of products of organic agriculture is increasing. Organic farming means excluding the use of synthetic inputs, such as synthetic fertilizers and pesticides or genetically modified organisms, but there are only a few regulations regarding heavy metal concentrations in soils. Thus a not negligible uptake of metals from the soil where the apple trees are grown may occur. Furthermore inorganic copper compounds being traditional fertilizers for apple trees are not considered as synthetic fertilizers, thus they are still used in organic apple farming for soil or foliar application. Thus also apples produced by organic agriculture may contain toxic elements, such as cadmium, chromium, copper, and lead. The concentrations of these elements were determined in whole apples, as well as in the flesh and peel in order to estimate the possible risk for human health. Prior to analysis using ICP-AES samples underwent a microwave assisted digestion. The LODs obtained are below the recommended maximum levels in vegetables/fruits by WHO. In all samples no Cu, Cr, and Pb could be detected. Only Ca was found in the peel of about a third of samples investigated in concentrations between LOD and LOQ (1-3 μg/g). 展开更多
关键词 Apples CADMIUM CHROMIUM copper LEAD organic farming.
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Effect of Copper, Zinc and Boron on Green Leaf Retention and Grain Yield of Winter and Spring Cereals
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作者 Syed Shah Sarah Hookway +3 位作者 Andrew Richards Carl Flint Sarah Wilkinson John Mark Fletcher 《Journal of Agricultural Science and Technology(B)》 2015年第6期365-375,共11页
Crop nutrition has a significant effect on disease incidence, resistance or tolerance of various crops. There is currently a lack of reliable recent UK-based research about the effect of copper, zinc and boron on dise... Crop nutrition has a significant effect on disease incidence, resistance or tolerance of various crops. There is currently a lack of reliable recent UK-based research about the effect of copper, zinc and boron on disease incidence, green leaf area (GLA), green leaf retention (GLR) and grain yield of winter wheat, spring wheat and spring barley. Data analysis showed that these trace elements had positive effects on GLR. These positive effects may have been due to the role of copper, zinc and boron in the production of defence related compounds (phenolics and lignin), which may have reduced the disease incidence resulting in prolonged GLR. Grain yield was significantly enhanced by the application of these trace elements on the crop grown on high pH calcareous soil, which can be partly attributed to enhanced GLR. Also trace elements have a positive role in reproductive growth, flowering and male fertility. On average, zinc was found to be the most consistent trace element in terms of enhancing GLR and grain yield. Across all trials, it was noted that for every 10% increase in GLA from trace elements, grain yields increased by 4.2% in 2012-2013, by 4.4% in 2013-2014 in winter wheat and by 3.9% in spring wheat in 2014. These are remarkably consistent and indicate that increasing GLA by 10% by early dough stage was associated with a yield improvement of about 4%. These trace elements also had a positive effect on grain protein content (GPC). This research concluded that the trace elements had positive effects in enhancing GLA and yield. It can be speculated that with the use of these trace elements, there may be more scope for using less robust or reduced rates of fungicides to control foliar diseases, which may help to maximize farm profits. 展开更多
关键词 Trace elements COPPER ZINC BORON CEREALS GLR grain yield.
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The toxic effects of copper on larvae of the barnacle species Chthamalus challengeri
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作者 齐磊磊 王影 +2 位作者 沙婧婧 王悠 唐学玺 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第2期400-409,共10页
With the increased use of copper (Cu)-based antifouling (AF) paints, copper has become a potential threat to marine organisms. Experiments were performed to investigate the effects of copper on larvae of the barna... With the increased use of copper (Cu)-based antifouling (AF) paints, copper has become a potential threat to marine organisms. Experiments were performed to investigate the effects of copper on larvae of the barnacle Chthamalus challengeri. These experiments attempted to identify a more sensitive index to monitor copper pollution in marine environments. The 24 h LC_50 ranged from 156.07 μg/L (nauplius Ⅱ) to 817.15μg/L (cypris) and the no observed effect concentration (NOEC) ranged from 81.75 μg/L (nauplius Ⅱ) to 571.04 μg/L (cypris). The cypris settlement rate declined significantly when copper concentrations 〉135 μg/L. No cypris was found in the copper concentration of 60 and 75 μg/L treatment groups stressed for 22 d. Nauplius Ⅱ moulting was not affected by exposure to copper for 24 h; however, when extended to 48 h, the percent moulted in 75 μg/L treatment group was declined to 37.12%, which was significant lower (P〈0.05) than that in the control group. The phototaxis of nauplius II decreased significantly when copper concentrations _〉45 μg/L. Despite an initial significant increase at copper concentrations of 30 μg/L, ammonia excretion rate decreased when copper concentrations ≥60 μg/L. These results suggested that: (1) nauplius Ⅱ could not develop to the cypris when the copper concentration ≥60 μg/L; (2) cypris settlement is more susceptible to copper than cypris mortality rate; (3) nauplius II is the most sensitive larval stage; (4) nauplius II ammonia excretion rate is the most sensitive index to copper and might be as the indicator for copper pollution monitoring. 展开更多
关键词 COPPER Chthamalus challengeri larval stage sensitivity pollution monitoring
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清宫铜器制造考——以雍、乾二朝为例 被引量:15
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作者 张丽 《故宫博物院院刊》 CSSCI 北大核心 2013年第5期94-133,163,共40页
中国铜器制造历史悠久,及至明清时期,以明宣德铜炉最为著名,至于清代铜器,则较少为人所知,似已无所作为。然而事实并非如此,文献和实物证明,有清一代,无论宫廷还是民间均有铜器制造,尤其清代的宫廷,曾大量制造各类铜器。本文主要依据雍... 中国铜器制造历史悠久,及至明清时期,以明宣德铜炉最为著名,至于清代铜器,则较少为人所知,似已无所作为。然而事实并非如此,文献和实物证明,有清一代,无论宫廷还是民间均有铜器制造,尤其清代的宫廷,曾大量制造各类铜器。本文主要依据雍、乾二朝的造办处档案及其他文献,对照实物,对清代铜器制造的规模、种类、特点及成就进行考证,同时也论及地方铜器制造和宣德铜炉的问题。 展开更多
关键词 清代 造办处 铸炉 铜作 地方制造
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