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1.
Neutron activation analysis has been used for the simultaneous determination of Cu, Mn, Zn and Na in plant materials. The heterocyclic dye PAN has been applied as a chelating agent to achieve the group chemical separation of Mn, Cu, Ni and Zn. Various factors which affect the formation and extraction of the PAN-metal chelates have been studied and optimized, using suitable aqueous solutions to selectively strip these elements from the organic phase. This procedure has been applied to the determination of these elements in ‘Bowen’s Kale’ and U.S. NBS Citrus-leaves and Tomatoleaves samples.  相似文献   

2.
Dermelj M  Ravnik V  Kosta L  Byrne AR  Vakselj A 《Talanta》1976,23(11-12):856-858
Destructive activation determination of the trace elements indium, manganese, arsenic and antimony in different samples of pure zinc metal by solvent extraction techniques is described. Determination of indium and manganese is based on the quantitative co-precipitation of both elements with lanthanum hydroxide, followed by their extraction with sodium diethyldithiocarbamate in the presence of potassium cyanide and their subsequent separation by selective stripping. The quantitative determination of arsenic and antimony is based on the extraction of their iodides from sulphuric acid solution with toluene.  相似文献   

3.
A double-line sequential injection system was developed for the spectrophotometric determination of several metal ions in waters. The proposed double-line configuration was used to enable adding sample and chromogenic reagents as merging zones. The methodology was applied to the spectrophotometric determination of copper, iron, manganese, and zinc in samples of diverse origins at the range of 0.15-5.00, 0.10-10.0, 0.48-4.00, and 0.11-5.00 mg/L, respectively. Different chromogenic reagents and detection wavelengths were used. The chromogenic reagents for iron and manganese were 1,10-phenanthroline and formaldoxime, respectively. Copper and zinc were both determined using the analytical reagent zincon. Analytical characteristics of the methodology, such as manifold parameters, buffer pH, and reagent concentrations were optimized, and interference of some of the metal ions commonly present in water sample was assessed. Results of the analysis were in agreement with those obtained by atomic absorption spectrometry. Repeatability, expressed as the relative standard deviation for 10 consecutive injections of water samples, was lower than 6%. The determination rate was approximately 36/h.  相似文献   

4.
5.
A method for the determination of copper in zinc by proton activation analysis using the63Cu(p, n)63Zn reaction has been developed.63Zn has to be separated chemically from gallium and copper activities formed out of the zinc matrix and from indium activity formed out of cadnium impurity. Gallium radionuclides are retained on a cation exchanger in chloride medium and the residual activity is extracted in di-isopropyl ether. Copper and indium are subsequently extracted with cupferron in chloroform. The method was applied to BCR reference materials with a copper concentration at the μg.g?1 level. The detection limit amounts to 0.5 μg.g?1.  相似文献   

6.
The instrumental neutron activation analysis (INAA) of industrially important steel samples, viz. IS-226, IS-2002, IS-2062, SS-304, SS-310, SS-316 and of copper base alloys, viz. high brass, gun metal and copper-silver alloys is carried out with a 2 Ci252Cf neutron source. The copper and vanadium content of all the steel samples and manganese content of former three steel samples are estimated by measuring the gamma activity of66Cu,52V and56Mn radioisotopes, respectively, using a high purity germanium (HPGe) detector coupled to a 4 K multichannel analyzer (MCA). Similarly, the copper content of copper base alloys was also determined.Dedicated to Prof. H. J. Arnikar, Professor Emeritus, University of Poona, on the occasion of his 75th birthday.  相似文献   

7.
火焰原子吸收光谱法连续测定菠萝中的铜、锌、铁、锰   总被引:6,自引:0,他引:6  
探讨了用微波消化罐消化样品、以火焰原子吸收光谱法在同一体系中测定菠萝中微量元素铜、锌、铁、锰的方法。考察了硝酸、过氧化氢的不同用量以及消化时间长短的影响和在同一体系中钢、锌、铁、锰的彼此干扰情况。在选定条件下,检测限铜为0.0060μg/mL、锌为0.0074μg/mL、铁为0.0040μg/mL、锰为0.0090μg/mL,相对标准偏差1.9%-4.7%,回收率93.2%-105%。  相似文献   

8.
A rapid radiochemical separation method based on the removal of metal ions by columns of C18-bonded silica gel after selective complexation by 8-quinolinol, ammonium pyrolidinedithiocarbamate or cupferron is described for the determination of manganese, copper and zinc in neutron-activated biological materials. The removal of the metal ions, either by adsorption or by a combination of filtration and adsorption on columns of C18-bonded silica gel, was investigated to optimise the separation procedure. Analysis of several National Bureau of Standards and International Atomic Energy Agency biological reference materials demonstrated the effectiveness of this technique. The method is simple and reliable and readily adaptable in all radiochemical laboratories. Furthermore, columns of C18-bonded silica gel have been successfully recycled a number of times without deterioration.  相似文献   

9.
10.
The extraction and extraction-chromatographic behavior of many elements in the tributylphosphate — HBr solution system has been studied. The investigation performed has made it possible to develop a simple technique for neutron activation determination of 22 impurity elements in high purity indium samples with detection limits from 0.1 ppm for Fe and Zr to 0.01 ppb for Na, Sc, Cu, As, La and W.  相似文献   

11.
Simultaneous determination of copper, zinc, cadmium and mercury with high sensitivity is possible by neutron activation analysis. After irradiation, the samples are digested and an initial separation of the four elements made by means of an ion-exchange resin. The elements in the separated fractions are then treated to give radio-chemical purity, precipitated, and their activities measured. A purely instrumental technique for the analysis of zinc in samples of biological material is also described. The samples are irradiated for a week and after the activity has decayed for about three months it is measured on a gamma-spectrometer.  相似文献   

12.
Determination of copper (Cu), zinc (Zn) and manganese (Mn) micronutrients in soil samples have been studied for an efficient fertiliser application. Plant-available micronutrients of soils were extracted with DTPA extraction procedure, then differential pulse stripping voltammetry (DPSV) and square wave stripping voltammetry (SWSV) methods were performed with inexpensive and disposable pencil graphite electrode for determination of Cu(II), Zn(II) and Mn(II). Parameters such as deposition potential, deposition time, pH and concentration of the supporting electrolyte were optimised for these ions. Under optimised conditions, the limits of detection were found as 0.01 mg L?1 for Cu(II) and 0.02 mg L?1 for Zn(II) and 0.25 mg L?1 for Mn(II). Relative standard deviation (%RSD) was 6.80, 8.86 and 3.29 for Cu(II), Zn(II) and Mn(II), respectively. The experimental study was conducted using a flame atomic absorption spectroscopy. The described stripping voltammetry methods were successfully applied for the determination of Mn(II), Cu(II) and Zn(II) in soil samples.  相似文献   

13.
A radiochemical procedure developed by the authors for neutron activation analysis of As, Cd, Cu, Sn, and Zn in beef extract samples is described, based on combined precipitation steps to isolate the elements to be determined. Nuclides are separated with high degree of purity and good chemical yields. Interferences from threshold reactions are discussed and calculated. Results are shown for analysis of six samples.  相似文献   

14.
15.
This article describes a detailed comparison between the original BCR sequential extraction procedure, step 2 of which involves treatment with 0.1 mol l−1 hydroxylammonium chloride at pH 2, and the revised BCR procedure (step 2: 0.5 mol l−1 hydroxylammonium chloride at pH 1.5). An intermediate protocol was also evaluated in which 0.5 mol l−1 hydroxylammonium chloride at pH 2 was used. The procedures were applied to five soil and sediment substrates: a sewage sludge-amended soil, two different industrially contaminated soils, a river sediment and an inter-tidal sediment. Extractable iron and manganese concentrations were measured to assess the effects of the procedural modifications on dissolution of the reducible matrix components. Trace elements copper, lead and zinc were also determined. Statistical analysis (two-tailed t-tests at 95% confidence interval) indicated that recovery of iron in step 2 was not markedly enhanced when the intermediate protocol was used. However, significantly greater amounts were isolated with the revised BCR scheme than with the original procedure. Copper behaved similarly to iron. Lead recoveries were increased by use of both modified protocols, with the greatest effect occurring for the revised BCR extraction. In contrast, manganese and zinc extraction did not vary markedly between procedures. The work indicates that the revised BCR sequential extraction provides better attack on the iron-based components of the reducible matrix for a wide range of soils and sediments.  相似文献   

16.
Stage-specific and age-dependent profiles of zinc, copper, manganese, and selenium in testis were examined in Wistar rats by both inductively coupled argon plasma-mass spectrometry (ICP-MS) with a microdissection technique and in situ elemental imaging of micro-PIXE analysis. The young adult animals (10 weeks old) contained higher levels of zinc and manganese in the seminiferous tubules at stages VII-VIII than stages XI through VI and IX-X and the levels were higher than those of the immature and old animals. Copper and selenium levels at stages VII-VIII of the young adult animals were also higher than those of the immature and old animals. In stages VII and VIII, zinc was higher in the central area of the seminiferous epithelium, where spermatozoa were localized, demonstrating a cell-specific property. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

17.
Preconcentration and determination of trace elements in seawater by chelation ion chromatography (CIC) was studied. For the retention of metal ions (0.25–0.30 M), ammonium acetate (at pH 4.8–5.1) and macroporous iminodiacetate chelating resin were used. This system (CIC) permits trace and ultra-trace determination of metals in a variety of complex matrices, in particular those with a high content of alkali and alkaline earth metals. Detection limits range from 0.1 to 0.5 ng. Satisfactory results are obtained in the range 0.05–0.5 μg/1 when 60 ml of sample are preconcentrated. In this work the contents of zinc, copper, nickel, cobalt and manganese in seawater from the Venice lagoon are presented. The results obtained by chelation ion chromatography are compared with those obtained using preconcentration of metals with dithizone and ammonium pyrrolidinedithiocarbamate in chloroform and analysed by graphite furnace atomic absorption spectrometry.  相似文献   

18.
Manganese (Mn), iron (Fe), copper (Cu), and zinc (Zn) concentrations were determined in the brain regions of normal 1-, 3-, 5-, 7-, 14-, 21-, 42-, 77-, and 147-day-old Wistar rats using inductively coupled plasma mass spectrometry (ICP-MS), and their maps were illustrated in color to visually compare the distribution of the elements at various stages of the growth process. Sagittal slices (1-mm thickness) sectioned at the level of the substantia nigra were divided into 18 regions, and the small slice samples were digested in microwave-assisted closed vessels for ICP-MS measurement. Mn, Fe, Cu, and Zn concentrations increased region-specifically with age, and their distributional maps showed some characteristics. These findings are discussed in terms of needs for these trace elements in the normal brain. Among new findings about their brain distribution, it is especially noteworthy that higher concentrations of Mn, Fe, and Zn were observed in the substantia nigra compared with those in neighboring regions. The mapping method in this work is expected to open up possibilities for screening of the in vivo element–element interrelationships among these essential elements.  相似文献   

19.
A method is proposed for the simultaneous determination of lead, copper and zinc in multimetal ores and their products by cyclic irradiation and measurement. The relative standard deviation is 10–20%, the total time required for the analysis of one sample is 10 min.  相似文献   

20.
Copper-, manganese-, and zinc-based ionic liquids (Cu{NH(2)CH(2)CH(2)OH}(6)[CH(3)(CH(2))(3)CH(C(2)H(5))CO(2)](2) (2), Cu{NH(CH(2)CH(2)OH)(2)}(6)[CH(3)(CH(2))(3)CH(C(2)H(5))CO(2)](2) (3A), Cu{NH(CH(2)CH(2)OH)(2)}(6)[CF(3)SO(3)](2) (3B), Cu{NH(CH(2)CH(2)OH)(2)}(6)[(CF(3)SO(2))(2)N](2) (3C), Mn{NH(CH(2)CH(2)OH)(2)}(6)[CF(3)SO(3)](2) (4), and Zn{NH(2)CH(2)CH(2)OH}(6)[CF(3)SO(3)](2) (5)) are synthesized in a single-step reaction. Infrared data suggest that ethanolamine preferentially coordinates to the metal center through the amine group in 2 and the hydroxyl group in 5. In addition, diethanolamine coordinates through the amine group in 3A, 3C, and 4 and the hydroxyl group in 3B. The compounds are viscous (>1000 cP) at room temperature, but two (3C and 4) display specific conductivities that are reasonably high for ionic liquids (>20 mS cm(-1)). All of the compounds display a glass transition (T(g)) below -50 °C. The cyclic voltammograms (CVs) of 2, 3A, 3B, and 3C display a single quasi-reversible wave associated with Cu(II)/Cu(I) reduction and re-oxidation while 5 shows a wave attributed to Zn(II)/Zn(0) reduction and stripping (re-oxidation). Compound 4 is the first in this new family of transition metal-based ionic liquids (MetILs) to display reversible Mn(II)/Mn(III) oxidation and re-reduction at 50 mV s(-1) using a glassy carbon working electrode.  相似文献   

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