Extraction of nickel,cobalt and other metals [Cu,Zn, Fe(III)] with a commercial β-diketone extractant

The extraction of nickel, cobalt, copper and zinc from ammoniacal solutions of ammonium carbonate or ammonium sulphate by solutions of Hostarex DK-16 in kerosene has been investigated as a function of phase contact time, aqueous-phase pH and organicphase reagent concentration. Besides copper, Hostarex DK-16 also partially extracts iron (III) from moderately acidic solutions whereas nickel, cobalt(II), copper and zinc are extracted from neutral or ammoniacal ammonium sulphate and ammonium carbonate solutions. Extraction decreases in the following order of metals: Cu > Co > Ni > Zn. Cobalt(III) is not extracted, but the complex of cobalt(II) with Hostarex DK-16 is slowly oxidized to a cobalt(III) complex which cannot be stripped even when 10 N sulphuric acid is used. Absorption spectra for cobalt complexes with Hostarex DK-16 (purified by preparative thin-layer chromatography) in benzene also suggest oxidation of cobalt(II) to cobalt(III) in the organic phase. Nickel, cobalt(II), zinc and copper can be stripped easily from organic solution with dilute solutions of sulphuric acid. Hostarex DK-16 extracts iron very slowly, nickel moderately rapidly and copper, cobalt(II) and zinc rapidly. Slope analysis and extraction isotherms suggest that the complexes CuR₂, NiR₂ ·HR and CoR₂·HR are present in the organic phase. Nickel can easily be separated from cobalt by extraction with Hosterex DK-16 after oxidation of cobalt in aqueous ammoniacal solution by hydrogen peroxide; however, LIX 64N seems to be a more promising extractant owing to the higher extraction of nickel under analogous conditions and the poorer extraction of zinc in comparison with Hostarex DK-16.     

ICP-AES法测定锡锭中铅铁锌铝锑铋铜砷8种杂质元素

研究了ICP-AES测定锡锭中8种杂质元素,考察了锡基体和共存元素对方法的影响.采用基体匹配消除了基体干扰,选择了对雾化进样影响最小的盐酸做试样溶解酸,选择了灵敏度高,干扰小的方法分析光谱线,考察了方法精密度和准确度.     

ICP-AES法连续测定土壤样品中的铜、铅、锌、铁、锰

采用混酸溶解土壤样品,用ICP - AES法连续测定铜、铅、锌、铁、锰五种元素,对比了三种消解体系,优化了盐酸复溶体系,优化了仪器的使用条件,方法检出限为Cu 3.31 μg·g-1、Pb 8.95μg·g-1、Zn 4.22 μg·g-1、Fe 3.85μg·g-1、Mn4.15 μg·g-1.在加标回收实验中,相对标准偏差为2.81％ ～3.92％ (n=10),方法回收率为96.2％ ～ 104.0％.用于分析矿石样品,分析结果与推荐值相符,可用于地质实验室对大量矿石样品的检测.     

Equilibrium distribution of Fe,Ni, Sb,and Sn between liquid Cu and a CaO-rich slag

Equilibrium measurements of the distribution of Fe, Ni, Sb, and Sn between a liquid Cu-O solution and a CaF₂-CaO-MgO-SiO₂ were carried out at 1500 K in a magnesia crucible. The results show that the studied solutes were in the states Fe(III), Ni(II), Sb(III), and Sn(IV), in the slag, for metal O contents ranging from 100 ppm to saturation at 2.1 pct. The Cu oxide solubility in the slag was also measured in absence of the solute elements. Its maximum solubility is about 4 ± 1 mass pct Cu₂O. The compositions at equilibrium allow determination of the activity coefficients (referred to pure oxide) of the four solute oxides in the slag. These values, expressed in round figures to take into account the experimental uncertainties, are 10 for Fe₂O₃, 20 for NiO, 10 for SnO₂, 1.6 10⁻² for SbO_1.5, and 60 for Cu₂O.     

化学计量学法辅助分光光度法同时测定痕量铁铜锌

用乘子法分光光度法,在pH5.5缓冲溶液中,利用金属－2－（5－溴－2－吡啶偶氮）－5－二乙氨基酚（5－Bt-PADAP)-OP三元络合物显色体系,对混合物中铁、铜、锌三组分进行了同时测定。     

火焰原子吸收光谱法快速测定纯镍中铁铜镁锰锌

提出了运用火焰原子吸收光谱法快速测定纯镍中铁铜镁锰锌的含量，介绍了铁铜镁锰锌最佳测定条件及呈良好线性范围的浓度，在测定中对样品中的干扰因素进行了综合考虑。该方法具有很好的灵敏度和重现性，具有方法步骤简单、操作容易、干扰少等特点。测定样品铁铜镁锰锌含量的相对标准偏差均小于1．0％（n=10）。标准加入回收率均在97．0％～99．0％（n=6）范围内。适用于纯镍材料中铁铜镁锰锌的含量控制分析和系统分析。     

铂饰品中Pt, Pd, Au, Ag, Cu, Ni, Zn, Fe的测定

试验研究建立了同一试料溶液连续、同时测定铂饰品中各成分的分析方法。主体Pt以氯铂酸铵称量法及火焰原子吸收光谱(FAAS)法或电感耦合等离子发射光谱(ICP-AES)法测定滤液中残留Pt进行补差而测定。主成分Pd,Au,Ag,Cu和焊料成分Ni,Zn,Fe以FAAS法或ICP-AES法测定。其方法回收率分别为:Pt99.9%~100%;Pd99.3%~99.7%;Au99.5%~l01.5%;Ag98.0%~100%;Cu97.7%~99.3%;Zn98.0%~99.0%;Ni94.0%~105%;Fe95.0%~99.0%。实际试样分析时,各成分质量分数之和一般在99.12%~l01.2%之间,接近于100%,间接说明方法的可靠性。本法适用于Pt-Pd二元体系和Pt-Pd-Au-Cu多元复杂体系的铂饰品的破坏分析,可用于校正X荧光光谱法无损检测铂饰品的分析结果。     

Alloy powders in the Fe—Cu, Fe—Cr, Fe—Mn, and Fe—Cr—Mn systems

Studies have been done on iron-copper, iron-chromium, iron-manganese, and iron-chromium-manganese powder alloys, which have been made by dispersing the melts with high-pressure nitrogen. The use of such alloys in the preparation of low-alloy construction materials eases the stringent specifications for the oxidation potential of the controlled gas medium, and it also produces a more uniform distribution of the alloying elements in the sintered material.     

湿法冶金(包括Zn、Mn、Cu、Ni、Co等)除铁的几种主要方法

论述了湿法冶金除铁的几种主要方法,包括中和水解法、黄钾铁矶法与针铁矿法除铁的化学反应、热力学分析及技术条件等.     

火焰原子吸收光谱法测定工业污泥中铜、铅、锌、镍

采用火焰原子吸收光谱法测定工业污泥中铜、铅、锌、镍,为环境保护提供有力的技术支持.被测元素的检出限为0.021～0.25 mg/L,相对标准偏差为2.73%～4.46%,回收率为97.0%～105.0%.方法准确度高、精密度好,结果令人满意.     

纯铜中铋,锑,砷,铁,镍,铅,锡,锌的光谱定量分析

本文介绍了一种光谱定量分析方法。该方法使用ＢＹＧ０１－１氧化铜光谱标准样品，对１－４号纯铜中铋、锑、砷、铁、镍、铅、锡、锌８个杂质元素进行定量分析。分析方法简单，测定结果与化学结果基本相符。方法的测定下限为３×１０￣（０６）。     

The insulo-acinar portal and insulo-venous drainage systems in the pancreas of the mouse, dog, monkey and certain other animals: a scanning electron microscopic study of corrosion casts

Scanning electron microscopy of vascular casts of the pancreas from monkies, cattle, pigs, dogs, cats, rabbits, guinea pigs and mice showed certain species differences in the occurrence of intralobular and interlobular islets and in the microcirculatory pattern of these islets. Interlobularly located islets were frequently found in the mouse and guinea pig, as has been previously established in the rat (Murakami and Fujita, 1992); they emitted insulo-venous efferent vessels directly draining into veins. In contrast, the intralobular islets in the guinea pig usually issued insulo-acinar portal vessels continuous with the lobular capillary network. In the mouse, they usually emitted both the insulo-acinar portal and insulo-venous efferent vessels. The insulo-venous efferent vessels, including those of the interlobular islets, could partly be portal in nature since they occasionally issued portal branches directed to the lobular capillary network. In rabbits, cats, dogs, pigs, cattle and monkies, as in men (Murakami et al., 1992), essentially all islets in the pancreas were intralobular in location and usually emitted the portal vessels only. In the mouse and rabbit, as in the rat (Murakami and Fujita, 1992), the islet received afferent vessels in its superficial aspect and issued efferent vessels from its deep aspect. In the Formosan monkey, as previously reported in the rhesus monkey (Fujita and murakami, 1973), the afferent vessels usually ran deep into the islet which emitted vessels from its superficial aspect. In other animals examined in this study, as in humans (Murakami et al., 1992), no consistent rule concerning the microcirculatory pattern within the islet could be determined.     

Identification and subcellular localization of a novel Cu,Zn superoxide dismutase of Mycobacterium tuberculosis

Periplasmic copper, zinc superoxide dismutases (Cu,ZnSOD) of several Gram-negative pathogens have been shown to play an important role in protection against exogenous superoxide radicals and in determining virulence of the pathogens. Here we report the cloning and characterization of the sodC gene, encoding Cu,ZnSOD, from the Gram-positive Mycobacterium tuberculosis. The predicted protein sequence contains 240 amino acids with a putative signal peptide at the N-terminus and shows approximately 25% identity to other bacterial sodC. Recombinant proteins of a full-length sodC and a truncated form lacking the putative signal peptide were overexpressed in Escherichia coli and affinity purified. Renatured recombinant M. tuberculosis sodC protein possessed characteristics of a Cu,ZnSOD. Immunoblotting with an antiserum against the recombinant M. tuberculosis Cu,ZnSOD allowed detection of a single polypeptide in the lysate of M. tuberculosis. This polypeptide has a similar size as the recombinant protein without the putative signal peptide indicating that the endogenous Cu,ZnSOD in M. tuberculosis might be processed and secreted. Furthermore, immunogold electron microscopic image showed that Cu,ZnSOD is located in the periphery of M. tuberculosis. The enzymatic activity and subcellular localization of this novel Cu,ZnSOD suggest that it may play a role in determining virulence of M. tuberculosis.     

Role of the electrostatic loop charged residues in Cu,Zn superoxide dismutase

We have expressed and characterized a mutant of Xenopus laevis Cu,Zn superoxide dismutase in which four highly conserved charged residues belonging to the electrostatic loop have been replaced by neutral side chains: Lys120 --> Leu, Asp130 --> Gln, Glu131 --> Gln, and Lys134 --> Thr. At low ionic strength, the mutant enzyme is one of the fastest superoxide dismutases ever assayed (k = 6.7 x 10(9) M(-1) s(-1), at pH 7 and mu = 0.02 M). Brownian dynamics simulations give rise to identical enzyme-substrate association rates for both wild-type and mutant enzymes, ruling out the possibility that enhancement of the activity is due to pure electrostatic factors. Comparative analysis of the experimental catalytic rate of the quadruple and single mutants reveals the nonadditivity of the mutation effects, indicating that the hyperefficiency of the mutant is due to a decrease of the energy barrier and/or to an alternative pathway for the diffusion of superoxide within the active site channel. At physiological ionic strength the catalytic rate of the mutant at neutral pH is similar to that of the wild-type enzyme as it is to the catalytic rate pH dependence. Moreover, mutation effects are additive. These results show that, at physiological salt conditions, electrostatic loop charged residues do not influence the diffusion pathway of the substrate and, if concomitantly neutralized, are not essential for high catalytic efficiency of the enzyme, pointing out the role of the metal cluster and of the invariant Arg141 in determining the local electrostatic forces facilitating the diffusion of the substrate towards the active site.     

ICP法同时测定工作场所中的锰、铜和锌

研究了用电感耦合等离子体(ICP)对工作场所中的锰、铜和锌进行同时测定的方法。优化了ICP的工作参数:射频功率发生器频率27.12 MHz,入射功率为1.2 kW,放射功率小于5W,载气流量1.2 L.min-1。三种元素的检出限在0.105~0.500之间,相对标准偏差(RSD)(n=6)均小于7%,回收率均在94.5%~103.6%之间。该方法用于工作场所中元素的测定,结果令人满意。     

Sodium pump distribution is not reversed in the DBA/2FG-pcy, polycystic kidney disease model mouse

Recently, it has been reported that Na,K-ATPase in the renal epithelia of human autosomal dominant polycystic kidney disease and cpk mouse, a murine model of autosomal recessive polycystic kidney disease, mislocates to apical plasma membrane and that mislocated Na,K-ATPase causes the cyst formation. Whether the DBA/2FG-pcy mice, which are presumably a suitable model for autosomal dominant polycystic kidney disease, also exhibit the reversal polarity of Na,K-ATPase localization was examined. Kidneys of newborn DBA/2FG-pcy mice, and those at early and late stages of cyst development were examined by immunohistochemical techniques. At any stage, abnormal distribution of Na,K-ATPase on the apical membranes of tubular epithelial cells could not be detected. It is suggested that cysts can be formed without reversed polarity of Na,K-ATPase distribution in pcy mice.