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1.
本文首次研究进口可利用含铜物料与进口铜矿属性的不同特性并建立鉴定方法,采用X荧光光谱法和X射线衍射光谱法联用技术建立铜矿和含铜物料属性的鉴别方法。通过X荧光光谱法对铜矿和含铜物料中元素进行定性半定量分析,再用X射线衍射光谱法对铜矿和含铜物料的特征谱峰进行扫描,与X衍射仪中标准卡片比对分析,能够确定铜矿和含铜物料的物相组成。结果显示:X荧光光谱法铜矿和含铜物料的共同特点铜的含量较高,达到冶炼铜对原料的要求,硅、铁、钠、钙和镁元素都能够检出。差异性在铅和锌元素在含铜物料中较高,在铜矿石中基本未检出;在X荧光光谱法检测出的金属元素,通过X衍射仪扫描后与标准图片比对,各元素以不同的形式存在于含铜物料中,且有规律可循。  相似文献   

2.
硫化铜矿中氧化铜测定的新方法   总被引:3,自引:0,他引:3  
  相似文献   

3.
The melting and solidifying processes are carried out using molecular dynamics simulations. The influencing mechanism of the simulation size and the crystal configuration after solidification on the molten and the solidification properties is explored. The results demonstrate that the crystal structure of solidified copper nanoparticle is sensitive to the size of the copper nanocubes. Polycrystalline appears in the solidified copper nanoparticle for the relatively larger copper cubes; correspondingly, the grain boundaries give rise to the increase of the average atomic energy. Whereas for the relatively small copper cubes, the solidified copper nanoparticles mainly present monocrystalline structure. Moreover, the relationship between the internal pressure of the liquid copper droplets and the droplet diameter is studied to clarify the surface tension property at nanoscale. It is found that the internal pressure of the liquid copper droplets is logarithmically linearly dependent on the diameter of the copper droplets, implying that the surface tension of the liquid copper is not sensitive to the diameter of the liquid copper droplets. The present findings will be helpful to the preparation of the copper nanoparticle‐based thin ribbon. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

4.
根据铜锍的组成结构特点,建立了一种测定铜锍中铜含量的方法,重点讨论了混合酸对铜锍进行溶解的前处理及样品滴定过程。方法铜的测定范围:4.80%~32.00%,回收率:97.70%~101.26%,精密度即标准偏差:0.026 %~0.10%。该方法能够较好地解决铜锍中铜含量测定难的问题。  相似文献   

5.
Seaweed Sargassum sp. biomass proved to be useful for the recovery of ionic copper from highly concentrated solutions simulating effluents from semiconductor production. In the case of solutions containing copper in the form of chloride, sulfate, and nitrate salts, the best pH for the recovery of copper was 4.5. It was observed that copper biosorption from copper nitrate solutions was higher than the recovery of copper from copper chloride or copper sulfate solutions. The continuous system used was constituted of four column reactors filled with the biomass of Sargassum sp. and showed high operational stability. The biomass of Sargassum sp. in the reactors was gradually saturated from the bottom to the top of each column reactor. The biomass of Sargassum sp. in the first column saturated first, followed by a gradual saturation of the remaining columns owing to preconcentration performed by the biomass in the first column. The biomass of Sargassum in the bioreactors completely biosorbed the ionic copper contained in 63 L of copper sulfate solution, 72 L of copper chloride solution, and 72 L of copper nitrate solution, all the solutions containing copper at 500 mg/L. Effluents produced after biosorption presented copper concentrations < 0.5 mg/L.  相似文献   

6.
根据铜锍的组成结构特点,建立了一种测定铜锍中铜含量的方法,重点讨论了混合酸对铜锍进行溶解的前处理及样品滴定过程。在4.80%~32.00%铜的测定范围内,加标回收率为97.70%~101.26%,相对标准偏差为0.24%~0.53%。方法能够较好地解决铜锍中铜含量测定难的问题。  相似文献   

7.
Polarographic, voltammetric and controlled-potential coulometric studies of copper(II) and copper(I) chloride in dimethylformamide are reported. The two chloride complexes of copper(II) are reduced in a total of three electrochemical steps to two copper(I)-chloride complexes and to copper(0). The two copper(I)-chloride species are reduced to copper(0) and oxidized to copper(II)-chloride complexes. The dissociation constant of the tetrachlorocuprate(II) complex has been polarographically estimated to be 10-25.  相似文献   

8.
Brown FR  Fernando Q  Ogura T 《Talanta》1991,38(3):309-312
The kinetics of the dissolution of copper metal in an aqueous solution containing copper(II) and an unsaturated organic ligand was followed by using an automated flow-injection analysis technique to determine the concentration of copper(I) in solution as a function of time. The results suggest that the rate of dissolution of the copper metal is dependent on electron transfer between the copper(II) and copper atoms on the surface of the copper metal, and on the stabilization of copper(I) by the unsaturated organic ligand in solution.  相似文献   

9.
The sorption of copper by suspended particulate matter from river water was investigated as a function of pH and solids concentration. Water was collected from the Delaware River and particulate matter was concentrated using Tangential-Flow Filtration (TFF). The adsorption of copper increased with increasing pH until pH 9.0. A decrease in copper adsorption was found for higher pH values. The adsorption of copper was greater for the samples with added copper than for the suspension for which no metal was added. An increase of copper adsorption proportional to particulate matter concentration was also observed. At both pH 6.0 and 7.0, there was a decrease in the adsorption of copper with increasing copper concentration.  相似文献   

10.
土壤铜污染的微生物及酶学指标研究   总被引:1,自引:0,他引:1  
通过室内培养试验,研究了土壤铜污染对土壤微生物基础呼吸及土壤脲酶、脱氢酶、酸性磷酸酶的影响。结果表明,土壤微生物基础呼吸在低水平铜(≤100mg/kg)添加下呈现出先上升后下降的趋势,而随着土壤铜添加水平的进一步提高(〉100mg/kg),微生物基础呼吸作用迅速增强;土壤脲酶则随着铜含量的增加呈现出不断下降趋势,土壤磷酸酶活性则在低水平下上升而随着添加水平的进一步提高迅速降低。可见,这两种酶对土壤铜毒害反应灵敏,可作为土壤铜污染评价的指标;而土壤脱氢酶则对铜含量的变化没有表现出明显的统计规律性,不适宜作为土壤铜污染评价的酶学指标。  相似文献   

11.
Experimental and theoretical EPR spectra of nanodispersed copper synthesized by the reduction of copper dichloride in aqueous solutions, thin films of electrolytic copper, and copper ions are analyzed. It is established that the reduction of copper dichloride in an aqueous solution in the presence of a surfactant yields copper nanoparticles. The EPR spectra are shown to be sensitive to the oxidation of copper nanoparticles in both an aqueous medium and in thin copper films prepared by electrolytic deposition.  相似文献   

12.
1 INTRODUCTION In 1945, Braude[1] found for the first time that adding copper (Cu) ten times the normal requisite amount into the feed can improve the production property of the animal obviously. Therefore, from then on copper has been widely applied in pig- breeding industry as an effective growth-promoting agent, especially in the process of intensive culture, which plays an important part in improving the growth of animal and the production property. However, at the same time, the high…  相似文献   

13.
The copper(Ⅱ) complexes of pyridine-3-carboxylic acid (nicotinic acid) and pyridine-2-carboxylic acid (isonicotinic acid) were synthesized, and their structures were characterized by elemental analysis, infrared spectrum, powder X-ray diffraction and so on. The results show that under experimental conditions, the ligands of synthesized copper nicotinate and copper isonicotinate are coordinated simultaneity with copper(Ⅱ) via the nitrogen of pyridine group and an oxygen of carboxylic acid group to form bidentate chelates. The crystal of copper nicotinate with two six-membered chelate rings belongs to monoclinic system, while that of copper isonicotinate having two five-membered chelate rings is of triclinic system. The tests show that the biological activities, such as the improvement of feed utilization, growth, anti-oxidation ability of organism and disease-resistant power, are different when copper nicotinate, copper inicotinate, copper-lysine chelate, copper-methionine chelate and copper sulphate are added in pig's feed, respectively. Due to its higher biological activity, less pollution and lower toxicity,copper nicotinate has wide potential applications as a feed additive.  相似文献   

14.
Oxidation of hydroquinone catalyzed by copper(II) complexes of poly-1-vinylimidazole, vinylamine-vinylacetamide copolymer, and polyethyleneimine was studied in aqueous solution at 25°C. The rate of oxidation was determined spectrophotometrically over several pH values. The rate of copper(II) reduction was evaluated from copper(I)–cuproin complex formation, and the reoxidation of copper(I) to copper(II) was observed by visible spectroscopy. Among the copper(II) complexes, poly-1-vinylimidazole complex exhibited excellent catalytic activity, which amounted to over 20 times that of aqueous copper(II) ion solution, while the reduction of copper(II) in the former system was slower than that in the latter system. The reoxidation of copper(I) to copper(II) was found to be completed immediately in the presence of polymer ligands such as poly-1-vinylimidazole, while copper(I) ion was only slowly reoxidized. The discussion of the reaction mechanism emphasizes the importance of the reoxidation process.  相似文献   

15.
以硝酸镧为镧源,柠檬酸为络合剂,水为溶剂,分别以硫酸铜,氯化铜和硝酸铜为铜源,采用溶胶-凝胶法制备了La2CuO4纳米晶。通过热重-示差扫描量热(TG-DSC),X射线衍射(XRD),红外光谱(IR),透射电子显微镜(TEM)和紫外-可见-近红外光谱(UV-Vis-NIR)等方法对La2CuO4粉体进行了测试和表征;研究了不同铜源对前驱体及La2CuO4粉体的热性能、相组成、官能团、显微结构及光学性能的影响。结果表明:以硫酸铜和氯化铜为铜源,600℃煅烧保温2 h,产物均含有杂质相,而以硝酸铜为铜源时,可获得单一的正交晶型的La2CuO4物相,晶粒尺寸80-100 nm。根据UV-Vis-NIR分析,La2CuO4的光学带隙依次为1.193 eV,1.258 eV,1.380 eV。  相似文献   

16.
铜含量对Cu/ZrO2和Cu—La2O3/ZrO2催化剂性能影响   总被引:4,自引:2,他引:2  
本文考察了铜含量对CuZrO2和Cu-La2O3ZrO2催化剂性能影响。结果表明,当铜含量较低时,铜在催化剂中以高分散状态存在,并随铜含量增加,催化剂活性线性增加。当铜含量超过某一值,部分铜组分以体相铜形式存在,催化剂活性随铜含量变化不明显。因此,高分散铜为影响CuZrO2催化剂活性主要因素。  相似文献   

17.
苏潜  黄妍  张颖 《分子催化》2016,30(2):151-158
采用离子交换法制备3种不同铜前驱体的Cu-SAPO-34分子筛催化剂,考察铜源对催化剂氨催化还原NO_x性能的影响,同时通过ICP、XRD、BET、H_2-TPR、XPS、NH_3-TPD等表征技术进行分析.活性结果表明,不同铜源制备的Cu-SAPO-34分子筛催化剂的NH_3-SCR高温活性基本相同,但中低温活性有较大差别.3种催化剂的中低温活性顺序为Cu(醋酸铜)-SAPO-34Cu(硫酸铜)-SAPO-34Cu(硝酸铜)-SAPO-34,以醋酸铜为铜源制备的催化剂中低温活性最高,在209℃NO_x转化率达85.2%.表征结果表明,不同铜源导致所制备催化剂的铜物种形式和数量及酸性强度不同,以醋酸铜为铜源制备的Cu-SAPO-34催化剂的Cu~(2+)起始还原温度最低,Cu~(2+)含量较多,酸性最强,因此其中低温活性最好.  相似文献   

18.
血清铜、锌、硒与恶性淋巴瘤关系的研究   总被引:1,自引:0,他引:1  
测定68例恶性淋巴瘤患者血清铜、锌、硒及铜/锌比值水平,采用t检验和非条件Logistic回归因素分析方法对测定结果进行分析。结果表明恶性淋巴瘤患者血清铜、铜/锌比值升高,而血清锌及硒水平降低。血清铜和铜/锌比值升高与肿瘤的负荷状态及病期明显有关,提示血清铜和铜/锌比值的测定对监测恶性淋巴瘤患者的病情变化有一定价值,非条件Logistic多因素分析表明,血清锌、硒可能是恶性淋巴瘤发病的保护因素;而  相似文献   

19.
海藻酸酮膜表面的配位结构及催化MMA聚合的性能   总被引:2,自引:0,他引:2  
将海藻酸钠(SA)与CuCl2.2H2反应得到一种配位聚合物海藻酸酮(Cu-An)。以ESR、电导率、IR和SPS方法对此配位聚合物进行表征,确定了组成与结构:同时研究了甲基丙烯酸甲酯(MMA)在该配位聚合物膜、HSO3^-和水体系催化引发作用下的聚合反应历程。结果表明,配位聚合物的中心离子Cu^2^+与两个海藻酸(An)链节单元上的两个羧羟基氧原子和两个离解氢原子的羧羟基氧原子以共价型配位,配位数为4.MMA在上述的催化引发体系中是按照自由基加聚反应历程进行聚合的,PMMA呈无规结构。Cu-An在催化引发体系中起着催化剂的配位催化作用。  相似文献   

20.
The mutual influence of copper(II) cations and nonionic surfactant alkylmonoethers on their simultaneous sorption by the hydrogen form of Purolite C 106 polyacrylic acid functionalized cation exchanger was investigated considering the suitability for the prevention of environmental contamination. Sorption isotherms were measured and sorption equilibrium coefficients calculated. The modelling of copper(II) sorption and copper(II) carboxyl complex formation was carried out. The sorption of copper(II) proceeds predominantly by complex (ionic and coordinate) bonding followed by the change in pH, also by single coordinate bonding. The mutual action of copper(II) and alkylmonoethers leads to a decrease in the equilibrium sorption for both copper(II) and the surfactant. The sorption of copper(II) and alkylmonoethers could be applicable for the purification of sewage including copper plating rinsewater from both contaminants simultaneously for the control of copper(II) and the surfactant in sewage effluents. Received: 15 May 2000 Accepted: 9 May 2001  相似文献   

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