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1.
Abstract

In the present study the concentration of heavy metals (Cu, Cr, Ni, Pb and Zn) in sediments collected from different sampling stations of the Leça river (Portugal) was determined, using Flame Atomic Absorption Spectrometry. In order to estimate the potential mobility of metals in these samples, the results of the total digestion were compared with those obtained by single extractions using EDTA and acetic acid as extractant solutions; in all samples studied, Cu and Zn were found to be the most mobile elements; Ni and Pb showed a smaller mobility in presence of either acidic medium and complexing ligands; Cr was found the least mobilizable element, given that the low extractability obtained with the two extractants tested in this work. In the single extraction tests, microwave energy was also employed to replace the conventional treatment and only in the case of the EDTA the results obtained were similar to those of the conventional procedure (recoveries between 90.16 and 98.76%); the precision (RSD, n=3) of the proposed microwave procedure for EDTA extractions was comparable to those of the conventional method with values always lower than 8% for all metals.  相似文献   

2.
In this work twelve elements (Al, B, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni and Zn) were determined in 30 honey samples from various locations within Poland and in two different types of honey--rape and honeydew. Trace elements (Al, B, Cr, Mn and Ni) were determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), however, major elements (Ca, K, Mg, Na) and Cu, Fe, Zn were determined by Flame Atomic Absorption Spectrometry (F-AAS). Cluster analysis of honey data revealed that the origin of honey samples correlated with their chemical composition. It was shown that rape honey includes lower amounts of manganese than honeydew honeys. Also honeydew honey includes much higher concentrations of Al, Cu, K, Fe and Ni in comparison with rape honey. Moreover honeydew honey was found to have a higher mineral content, which reflects sources from which the honey is composed. Trace element analysis showed that the differences in the values found in honey samples could be used as evidence of the quality of honey samples.  相似文献   

3.
An analytical exercise between two laboratories was performed in order to compare the elemental composition of a water sample. The metal concentration of Cr, Cu, Fe, Mn, Ni, Pb, and Zn in the water sample was analyzed by Total Reflection X-Ray Fluorescence and Atomic Absorption Spectrometry. The analysis by Total Reflection X-Ray Spectrometry was realized by an Ital Structures TX-2000 and the analysis by Atomic Absorption Spectrometry was made by a Perkin Elmer Spectrophotometer Model 3110. Results show a good agreement in the metal concentrations obtained by both techniques. The variation coefficient between the results with both techniques was less than 14%. Therefore, it is possible to conclude that both techniques are reliable and adequate for the determination of these elements in environmental water samples.  相似文献   

4.

Silica is removed from fly ash sample by hydroflourination for its effective determination gravimetrically and the remaining residue is subjected to lithium tetraborate (Li2B4O7) fusion followed by dissolution in dilute nitric acid to obtain a clear solution in which elements including aluminum (Al), iron (Fe), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), nickel (Ni), copper (Cu) and zinc (Zn), have been determined by Flame Atomic Absorption Spectrometry (FAAS). Two fly ash samples analyzed by the proposed method have been received from the National Council of Cement and Building Materials (NCCBM), India (proposed CRM in future) and fly ash CRM 1633 (b) from NIST, USA. The validity of the method has been established by analyzing fly ash CRM 1633 (b) as reference standard. The standard deviation has been calculated for each measurement.  相似文献   

5.

Various sludge samples from different domestic and industrial wastewater treatment plants were analyzed by Flame Atomic Absorption Spectrometry to evaluate their total and available contents of heavy metals (Cu, Cr, Ni, Pb, Zn and Fe). The EDTA and acetic acid single extraction procedures were applied to these samples with the aim to study the leaching behaviour of the metals in the different sludges and also to predict their possible mobility when these wastes are disposed on the environment and landfills. In acidic medium, a higher extraction efficiency was observed for the major part of the elements studied in the industrial sludges, except for Ni and Zn, which were also considerably released from domestic sludges. In contrast, in the presence of the EDTA complexing ligand, a more elevated mobility of metals was found in the domestic sludges and little or no metals were released from the industrial sludges. Moreover, the results of the microwave total digestions were compared, for all metals, with those obtained using a more simplified pseudototal digestion procedure (based on the EPA Method 3051, named microwave assisted acid digestion of sediments, sludges, soils and oils) and a good agreement was found between them, except for Cr and Ni in some particular samples. The between-batch precision (expressed as RSD) of both compared digestion methods was very similar and values lower than 7.7% were obtained in both cases. A certified domestic sludge material (SRM 2781) was employed to validate the two digestion procedures and no significant differences were found between the certified and experimental values for all the elements studied.  相似文献   

6.
凤仙花植株不同部位微量元素含量的比较分析   总被引:2,自引:0,他引:2  
The samples of pueraria lobata ohwi were digested by HNO3 + HClO4 .contents of the next trace elements Fe,Zn,Cu,Mn,Ca,Mg,Co,Cr,Ni,Cd,Pb and Al in the bloom,base,stem,and leaf of Impatiens balsamina have been determined by Flame Atomic Absorption method.The result show that the recovery is about 97.5%-103.2%,and the RSD<2.7%,with good accuracy and precision.The order of the content of the trace elements of high to low is as follows:leaf>stem>bloom>base.The importance of essential trace elements Zn,Fe,Mn,Cu for human each has a higher content.In addition,toxic trace elements such as lead,arsenic and cadmium are also found.  相似文献   

7.
I. Lavilla 《Talanta》2009,80(1):109-116
In this work, ultrasound-assisted emulsification with a probe system is proposed as a rapid and simple sample treatment for atomic spectrometric determinations (Electrothermal Atomic Absorption Spectrometry, Inductively Coupled Plasma Optical Emission Spectrometry, Flame Atomic Absorption Spectrometry and Cold Vapour Atomic Absorption Spectrometry) of trace elements (As, Cd, Cr, Cu, Hg, Mg, Mn, Ni, Sr and Zn) in cosmetic samples such as shampoos, gel (hair gel), crèmes (body milk, hair conditioner) and oil (body oil). The type of dispersion medium, the sample mass-to-dispersion medium volume ratio, as well as the parameters related to the ultrasound-assisted emulsification (sonication amplitude and treatment time) were exhaustively studied. Only 1 min of ultrasonic shaking and a dispersion medium containing 0.5% (w/v) of SDS + 3% (v/v) of HNO3 or HCl allows obtaining a stable emulsion at least for 3 months. Thermal programs, nebulization of emulsions, speed of pumps and concentration of reagents used in cold vapour generation were optimized. Calibration using aqueous standards was feasible in all cases. Calibration by the standard addition method and recovery studies was also applied for validation. Microwave-assisted digestion and Inductively Coupled Plasma Mass Spectrometry were used for comparison purposes. Relative standard deviations from analysis of five independent emulsions were less than 9% in all cases.  相似文献   

8.
Peng Wu  Rui Liu  Xiandeng Hou 《Talanta》2009,77(5):1778-635
Flame furnace atomic absorption spectrometry (FF-AAS) is a newly developed flame atomic absorption spectrometric technique based on arranging a flame furnace onto the top of the flame burner head. In this fundamental investigation, 25 elements were carefully tested by using either thermospray FF-AAS or tungsten coil electrothermal vaporization FF-AAS, of which 15 volatile and semi-volatile elements (Cd, Tl, Ag, Pb, Zn, Hg, Cu, Sb, Bi, Te, In, As, Se, Sn and Au) exhibited better limits of detection compared to those by conventional FAAS; however, non-volatile or refractory elements (Fe, Co, Ni, Cr, Mn, Pd, Pt, Al, Be and V) showed inferior sensitivities by the proposed methods.  相似文献   

9.
Summary The analysis of ashes being of increasing importance, a reference material was prepared from fly ash of a city waste incinerator. The procedures of preparation, homogeneity and stability testing are described as well as the way of certification of elements of major importance: Cd, Co, Cr, Cu, Fe, Hg, Ni, Pb, Zn, Sb, Se and Tl.
Zertifizierung der Gehalte an Cd, Co, Cu, Fe, Hg, Ni, Pb, Zn, Sb, Se, Tl und Cr in einer Stadtmüll-Verbrennungsasche
Zusammenfassung Da die Analyse von Aschen zunehmend an Bedeutung gewinnt, wurde von der Flugasche einer Stadtmüll-Verbrennungsanlage ein Referenzmaterial hergestellt. Die Methoden der Herstellung sowie der Homogenitätsund Stabilitätsprüfung werden beschrieben und die Art der Zertifizierung der Elemente von hauptsächlicher Bedeutung aufgezeigt (Cd, Co, Cr, Cu, Fe, Hg, Ni, Pb, Zn, Sb, Se, Tl).
  相似文献   

10.
In this work, a simple, rapid, reliable and low cost method for simultaneous electrochemical determination of As, Cu, Hg and Pb ions, on a vibrating gold microwire electrode combined with stripping voltammetry, is described for the first time.The multi-element detection was performed in the presence of oxygen by differential pulse anodic stripping voltammetry (DPASV) in HCl 0.1 M with NaCl 0.5 M. This media was found optimum in terms of peak resolution, peak shape and sensitivities, and has a composition similar to seawater to which the method could potentially be applied. The gold microwire electrode presented well defined, undistorted, sharp and reproducible peaks for trace concentrations of Cu, Hg and Pb and As presented a reproducible peak with a small shoulder. Using a gold vibrating microwire electrode of 25 μm diameter and 30 s deposition time, the detection limits of As, Cu, Hg and Pb were 0.07, 0.4, 0.07 and 0.2 μg L−1, respectively. Possible effects of Al, Cd, Cr, Fe, Mn, Ni, Sb and Zn were investigated but did not cause any significant interferences.Finally, the method was applied for the simultaneous determination of these four metals in unpolluted river water samples and the results were validated by Atomic Absorption Spectroscopy with Electrothermal Atomization (AAS-EA) or by Inductively Coupled Plasma Mass Spectrometry (ICP-MS).  相似文献   

11.
A novel silica sorbent, silica gel-immobilized 5-aminoisophthalohydrazide (SiO2-APH), was prepared by the condensation of 3-chloropropyl-functionalized silica gel with 5-aminoisophthalohydrazide (APH) derived from dimethyl 5-aminoisophthalate as a starting material and used for separation and preconcentration of Cu, Zn, and Pb metals in water samples using Flame Atomic Absorption Spectrometry (FAAS). The characterization of the new sorbent was carried out by Elemental Analysis, Thermogravimetric Analysis (TGA) and Fourier Transform Infrared Spectroscopy (FTIR). Important analytical parameters including as pH, amount of sorbent, type and amount of eluting solvent, sample volume, vortex and ultrasonic bath time, matrix ions that effect the developed SiO2-APH-solid phase extraction (SPE) method were investigated and optimum parameters were detected. Recoveries of examined metals were obtained as 98% for Cu and Pb and 101% for Zn. The relative standard deviation (RSD, n = 8) of Cu, Zn and Pb metals were 3.2, 2.8 and 1.6%, respectively. Limit of detections (LODs) (n = 10) were found as 2.7 μg L−1 for Cu, 7.4 μg L−1 for Zn and 3.5 μg L−1 for Pb μg L−1. The accuracy of the new method was assessed by analyzing of TMDA-51.4 and TMDA-70.2 certified reference materials. The results obtained for metals were in a good agreement with certified values. Addition/recovery test was applied to the real well, river, dam and stream water samples to check the accuracy of the method. The results showed that the developed SiO2-APH-SPE method can be effectively used as an alternative method for determination of Cu, Zn, and Pb metals in water samples.  相似文献   

12.
《Analytical letters》2012,45(3):509-534
Abstract

The sequential determination of 14 trace metals, Al, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Mo, Cd, Sb and Pb, in rain and river water samples has been investigated using an inductively coupled plasma mass spectrometry (ICP-MS) with a graphite rod electrothermal vaporizer (ETV) in the presence of the mixed modifier of palladium nitrate and magnesium nitrate. The sensitivity enhancements due to the presence of the modifier were observed for all analyte elements. Detection limits as high as 0.52, 0.13, 0.89, 0.35, 1.76, 0.5, 0.9, 0.5, 0.04, 1.03, 0.28, 0.07, 0.1 and 3.78 pg, respectively, for Al, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Mo, Cd, Sb and Pb have been achieved. For the determination of trace metals in both rain and river water samples by this method, the repeatibility of sample solution were very good, i.e. from 1% to 7% (as a coefficient variation) and the recoveries of elements were good enough, i.e. from 81% to 106%, by using a standard addition method. There was no difference between the results obtained by nebulizer ICP-MS and those obtained by this method, except for zinc and arsenic.  相似文献   

13.
《Analytical letters》2012,45(15):2513-2520
Slotted Quartz Tube (SQT) is a simple device that provides a sensitivity enhancement of 2–5 times in Flame Atomic Absorption Spectrometry (FAAS) depending on the element. A Gas Screen-Slotted Quartz Tube (GS-SQT) was designed to further increase sensitivity. For this purpose, two slotted gas chambers were fixed on the left and right sides of a burner head and Ar gas was supplied into these chambers perpendicular to the light path to produce two thin layers of gas screen. It was observed that these Ar screens can move up the flame tails in two ends of SQT. In addition to an increase in sensitivity by the use of SQT, Ar screen resulted in a further improvement in characteristic concentrations, C0, by a factor of 1.60 for Cd, 2.01 for Co, 1.42 for Cu, 1.94 for Mn, 1.86 for Ni, 1.78 for Pb, 1.62 for Se, and 1.09 for Zn. In addition to the enhancement in sensitivity, gas screen also helps by protecting the spectrometer from the adverse effect of using slotted quartz tube. The system is very simple and low-cost; it can be produced and applied easily.  相似文献   

14.
Summary Methods for the determination of Bi, Co, Cu, Fe, Mn, In, Ni, Pb, Sb and Zn in phosphoric acid by ETA-AAS using the platform technique were developed. The detection limits are in the range of 1 to 30 ppb for conc. H3PO4. Relative standard deviations of 5–10% at 10 times the detection limits were achieved. The results obtained by five different atomic spectroscopic methods are in good agreement (direct Zeeman-ETA-AAS, D2-ETA-AAS and FAAS; OES and FAAS after trace extraction).  相似文献   

15.
The present research was conducted to study heavy metal contamination in roadside soil viz. (i) at sites having more than two traffic signals (ii) roads having only one traffic signal and (iii) roads having no traffic signals. The samples were collected and analyzed for seven heavy metals i.e. cadmium (Cd), lead (Pb), copper (Cu), nickel (Ni), iron (Fe), manganese (Mn) and zinc (Zn) by Atomic Absorption Spectroscopy (AAS) following the acid digestion of the respective soil samples. The range of the metals observed in soil having more than two traffic signals were Cd (0.17–1.01), Pb (259.66–2784.45), Cu (15.51–65.90), Ni (13.31–98.13), Fe (325.64–5136.37), Mn (57.95–166.43), and Zn (91.34–166.43) mg kg?1 respectively. Similarly, the range of metals analyzed in samples collected from the roadside having only one traffic signal were Cd (nd–0.80), Pb (145.95–308.09), Cu (0.82–18.04), Ni (18.29–59.36), Fe (88.51–3649.42), Mn (25.88–147.34) and Zn (8.97–106.11 mg kg ?1) respectively. However, the range of metals at roads having no traffic signals were Cd (0.0–0.57), Pb (8.34–58.20), Cu (2.88–5.81), Ni (3.34–73.80), Fe (55.34–332.81), Mn (2.98–98.73) and Zn (1.23–46.6 mg kg?1) respectively. Cd, Cu, Ni, Fe, Mn and Zn in soil were present within the normal range of background levels, whereas lead was reported in high concentration. The level of lead had a correlation with the traffic density attributing its origin to vehicular exhaust. The values from three different sites of monitoring suggest that automobiles are a major source of the studied metals for the roadside environment.  相似文献   

16.
This paper describes the extraction/pre-concentration of Zn from diesel oil and its determination by Flame Atomic Absorption Spectrometry (FAAS), proposed as a novel approach for these kinds of analyses and the multivariate optimization of the proposed procedure. The extraction of Zn is based on the emulsification of an aqueous solution containing Triton X-114 and HNO3 with diesel oil samples followed by breaking of the emulsion by heating. The aqueous phase obtained after the emulsion breaking was collected and used for Zn quantification by FAAS. The methodology was optimized using a Doehlert design and the system variables were the concentrations of surfactant and HNO3 in the solution employed in the emulsification and the temperature used in the emulsion breaking. The ratio between absorbance and the time required to break the emulsions was taken as response. Two sets of experiments, using different emulsifier agents, were run: the first one using Triton X-100 and the second one using Triton X-114. At optimized conditions, the emulsions were prepared by mixing 10 mL of diesel oil with 2 mL of a solution containing 5% w/v of Triton X-114 and 15% v/v of HNO3 and broken by heating at 80 °C. The proposed analytical procedure was applied in the analysis of six real samples of diesel oil and a recovery test was carried out by spiking the samples with known amounts of Zn (25 and 50 μg L−1), added as organometallic oiled standard. Recovery percentages achieved in this test were between 92 and 109%.  相似文献   

17.
Summary The polarographic behaviour of Cd, Pb, Ni, Tl and U(VI) has been described in 0.1 M isoquinoline formate as base electrolyte. In all cases well defined reversible waves were obtained and determinations are possible in the presence of Mo, Co, Zn, Mn, Te, In, Se, Fe, Cr, V, Th, Zr, As, Sb, Ag, Hg and Cu.
Polarographische Bestimmung von Cadmium, Blei, Nickel, Thallium und Uran(VI) in Isochinolinformiat
Zusammenfassung Das polarographische Verhalten von Cd, Pb, Ni, Th. und U(VI) in 0,1 M Isochinolinformiatlösung wird beschrieben, Bestimmungsmöglichkeiten werden aufgezeigt. In allen Fällen werden gut definierte reversible Stufen erhalten. Folgende Elemente stören nicht: Mo, Co, Zn, Mn, Te, In, Se, Fe, Cr, V, Th, Zr, As, Sb, Ag, Hg, Cu.
  相似文献   

18.
Seven synthetic graphite powders of different grade of purity were analyzed by means of INAA, WDXRF, EDXRF, DC-OES directly and using ICP-MS, ICP-OES, ETAAS and FAAS in combination with various sample preparation techniques. On the basis of a statistical evaluation of the results obtained, for the trace elements Al, Ca, Cr, Cu, Fe, Mn and Ni, reference values were established and, for the elements As, Co, Mg, Mo, Pb, Sb, Si, Sr, Ti, V, Zn and Zr, informative values are given. The analyzed reference materials are commercially available.  相似文献   

19.
The epithermal neutron shape factor, α of the inner and outer irradiation sites of the Ghana Research Reactor-1 (GHARR-1) was determined obtaining results of 0.105 for the inner (Channel 1) Irradiation site and 0.020 for the outer (channel 6) irradiation site. The neutron temperatures for the inner and outer irradiation sites were 27 °C and 20 °C, respectively. The α values used in Westcott Formalism k0 INAA was applied to determine multi elements in 13 Ghanaian herbal medicines used by the Centre for Scientific Research into Plant Medicine (CSRPM) for the management of various diseases complemented by Atomic Absorption Spectrometry. They are namely Mist. Antiaris, Mist. Enterica, Mist. Morazia, Mist. Nibima, Mist. Modium, Mist. Ninger, Mist Sodenia, Mist. Tonica, Chardicca Powder, Fefe Powder, Olax Powder, Sirrapac powder and Lippia Tea. Concentrations of Al, As, Br, K, Cl, Cu, Mg, Mn, Na and V were determined by short and medium irradiations at a thermal neutron flux of 5×1011 ncm−2 s−1. Fe, Cr, Pb, Co, Ni, Sn, Ca, Ba, Li and Sb were determined using Atomic Absorption Spectrometry (AAS). Ba, Cu, Li and V were present at trace levels whereas Al, Cl, Na, Ca were present at major levels. K, Br, Mg, Mn, Co, Ni, Fe and Sb were also present at minor levels. Arsenic was not detected in all samples. Standard Reference material, IAEA-V-10 Hay Powder was simultaneously analysed with samples. The precision and accuracy of the method using real samples and standard reference materials were evaluated and within ±10% of the reported value. Multivariate analytical techniques, such as cluster analysis (Q-mode and R-mode CA) and principal component analysis (PCA)/factor analysis (FA), have been applied to evaluate the chemical variations in the herbal medicine dataset. All the 13 samples may be grouped into 2 statistically significant clusters (liquid based and powdered herbal medicines), reflecting the different chemical compositions. R-mode CA and PCA suggest common sources for Co, Mg, Fe, Ca, Cr, Ni, Sn, Li and Sb and Na, V, Cl, Mn, Al, Br and K. The PCA/FA identified 3 dominant factors as responsible for the data structure, explaining 84.5% of the total variance in the dataset.  相似文献   

20.
Abstract

Mushrooms are efficient accumulators of essential and toxic elements. Although oyster (Pleurotus spp.) mushrooms are widely commercialized and consumed, few data exist regarding trace elements content and bioaccumulation in cultivated P. ostreatus and P. eryngii, while no data are available for P. nebrodensis. The contents of Al, As, Ba, Cd, Co, Cr, Cs, Cu, Fe, K, Mn, Na, Ni, Pb, Rb, Sr, V, and Zn were monitored using inductively coupled plasma-mass spectrometry (ICP-MS) and atomic emission spectrometry (AES) in P. ostreatus, P. eryngii, and P. nebrodensis mushrooms and their cultivation substrates that include wheat straw (WHS), grape marc (GMC), olive leaves (OLV), and two-phase olive mill wastes (OMW), separately or in mixtures. Bioaccumulation factors (BAFs) less than 0.3 were obtained for Al, Ba, Co, Cr, Fe, Mn, Ni, Pb, Sr, and V; BAFs exceeding 1 for K?>?Zn?>?Cd?>?Cr?>?Rb?>?As, while the BAFs for Na were less 0.7. Mushrooms grown on OLV and OMW presented lower BAFs than those grown on WHS and GMC for all elements except for K, Cd, and Cu. P. ostreatus was an effective accumulator for Cr, Fe, and Zn; P. eryngii for Al, Cs, Ni, and V; and P. nebrodensis for As and Cd. The estimated daily intakes (μg kg?1 body weight) from mushroom consumption were less than 0.010 for As, Cd, Co, Cs, Pb, and V, 0.010–0.10 for Ba, Cr, Ni, and Sr, 0.10–5.0 for Al, Cu, Fe, Mn, Rb, and Zn, 65–83 for Na, and 858–1030 for K. Overall, the mushrooms studied provide significant amounts of K, adequate amounts of Mn and Zn and low amounts of Na and toxic elements.  相似文献   

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