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1.
In various samples of marine organisms from the central Adriatic Sea 210Po was determined by alpha spectrometry and thirteen heavy metals (Mn, Fe, Co, Cr, V, Ni, Cu, Zn, Cd, As, Sn, Hg and Pb) by energy dispersive, polarised X ray fluorescence spectrometry (EDPXRF). 210Po activity concentration ranged between 0.3 and 44.6 Bq kg−1 fresh weight. The data obtained depend upon the type of the marine organism; among the pelagic species, anchovy displayed the highest polonium concentration. Typical concentration ( \upmu \textg·\textg(\textfresh) - 1 ) \left( {\upmu {\text{g}}\cdot{\text{g}}_{{({\text{fresh}})}}^{ - 1} } \right) ranges were as follows: Mn: <1.32–1.73; Fe: 4.11–94.27; Co < 0.13–0.23; Ni: <0.13–0.52; Cu: 0.37–145.31; Zn: 0.46–16.46; Cd: <0.10–0.25; As: 0.36–60.52; Hg: <0.13–0.70; Pb: <0.13–0.35, Sn: <0.20–12.67; V and Cr were always <1.32. The data obtained are also compared with those obtained by other authors for the same organism coming from other Italian seas.  相似文献   

2.
The atmospheric deposition fluxes of 7Be, 210Pb and 210Po at Xiamen were measured. The samples were collected from March 2004 to April 2005 and the sampling period was one month. The 7Be and 210Pb activity were measured using HPGe γ-spectrometer after concentration using Fe(OH)3 co-precipitation method. The 210Po was counted with an α-spectrometer after the sample was digested and spontaneous plated onto a silver planchet. At Xiamen, the atmospheric deposition fluxes of 7Be varied between 0.11 and 2.93 Bq·m−2·d−1 and the average was 1.64 Bq·m−2·d−1; 210Pb fluxes varied between 0.04 and 0.85 Bq·m−2·d−1, and the average was 0.51 Bq·m−2·d−1; 210Po fluxes varied between 0.002 and 0.133 Bq·m−2·d−1, and the average was 0.061 Bq·m−2·d−1. There were positive correlations between the deposition fluxes of 7Be, 210Pb or 210Po and the amount of precipitation. The residence time of aerosols varied between 6.0 and 54.0 days with a mean of 27.1 days, which were calculated by 210Po/210Pb fluxes ratios.  相似文献   

3.
210Po in the daily diet in Korea was analyzed and the ingestion dose from an intake of 210Po was estimated by considering the dietary habit of a Korean person. The 210Po concentrations of a leafy vegetable (0.36 Bq·kg−1 for lettuce) in the terrestrial food were higher than those of grain, whereas Chinese cabbage had a lesser 210Po concentration (0.019 Bq·kg−1). The 210Po concentration of the animal product was similar to those detected in the grain and vegetable. The 210Po concentrations in the shell and crustaceous were high from 19.1 to 33.0 Bq·kg−1, however, its value fell in the overall range of the reported values. The effective dose from 210Po for an adult from the Korean population was about 269.4 μSv·y−1. Nearly 80% of the ingestion dose from the intake of 210Po was attributed to the consumption of seafood. It suggests that the marine food ingestion is a critical pathway for natural 210Po to the Korean population.  相似文献   

4.
Marine sediment cores were collected from two stations at East Malaysia coastal waters on June 2004. Activity concentrations of 210Pb in sediment core were ranged from 11 Bqkg−1 to 84 Bqkg−1 dry wt. for SR 01 and 4 Bqkg−1 to 66 Bqkg−1 dry wt. for SB 03. Meanwhile, activity concentrations of 226Ra in sediment core were varied significantly depending on the sampling location of SR 01 and SB 03 with ranged 17–26 Bqkg−1 dry wt. and 8–11 Bqkg−1 dry wt., respectively. The activity ratios of 210Pb/226Ra were no significantly different at all sampling stations with an average of 1.78. Refer to the entire results; the activities of 210Pb and 226Ra were higher at station SR 01 than station SB 03, but contrast with ratio of 210Pb/226Ra. The reasons of different 210Pb and 226Ra activity concentration and distribution of their ratios were strictly related to their half lives, environment origin, potential sources and behavior.  相似文献   

5.
The uptake of Cr, Mn, Ni, Cu, Zn, Cd and Pb in soft tissue of Perna perna mussels and their shells has been studied in aquarium experiments in which mussels were exposed for 30 or 60 days to seawater spiked with different concentrations of these contaminants (125 and 500 μg L−1). Tissue samples were analyzed after acid digestion by conventional solution nebulization ICP–MS. Laser ablation ICP–MS was used for the quantitative determination of trace elements in different areas of the corresponding shells. With the exception of Mn and Zn, all other elements studied showed a significant concentration enhancements in soft tissue, with the magnitude of this enhancement following the order: Cr > Ni > Cd > Cu > Pb. A corresponding increase in most contaminants, although less pronounced, was also observed in the newly formed growth rings of mussel shells, contributing to the validation of Perna perna mussel shell as a bioindicator of toxic elements.  相似文献   

6.
Zigetang Lake located in the central Tibetan Plateau was selected for the purpose of understanding of recent sedimentation rates. Based on 137Cs dating marker, the sediment rate was 0.077 cm·yr−1. The sedimentation rate was calculated to be 0.071 cm·yr−1 and 0.029 g·cm−2·yr−1 on the basis of 210Pb CIC model. 210Pb CRS model was also used for understanding of recent sedimentation change. The sediment accumulation rates for the CRS model ranged from 0.022 to 0.038 g·cm−2·yr−1 with an irregular high value of 0.12 g·cm−2·yr−1 around 1932 at Zigetang Lake core in the past eighty years.  相似文献   

7.
Inventories and fluxes of 210Pb, 228Ra and 226Ra were determined in sediment cores collected at nine stations covering of the southern South China Sea and Malacca Straits with the thickness of water column between 42 and 83 m depth. The inventories of 210Pb, 228Ra and 226Ra were calculated range from 0.15–2.55 Bq cm−2, 0.05–0.40 Bq cm−2 and 6.83–83.63 Bq cm−2, meanwhile the fluxes ranged from 0.005–0.079 Bq cm−2 yr−1, 0.009–0.048 Bq cm−2 yr−1 and 0.003–0.037 Bq cm−2 yr−1, respectively. The results show that the highest inventories and fluxes for 210Pb, 228Ra and 226Ra were found at station WC 01 and EC 05. Because there are additional sources of 210Pb, 228Ra and 226Ra, where water transport will brings more dissolved isotopes, influence of the transportation and deposition of suspended particles, fast rate of regeneration and greater production of those radionuclides and others.  相似文献   

8.
The distributions of 210Po and 210Pb in the intermediate layer (400–2000 m) of the northwestern North Pacific were determined to elucidate the export flux of particulate matter. 210Po generally showed depletion relative to 210Pb in the intermediate layer, suggesting that 210Po was scavenged by particles. Because the removal rate constants of 210Po in the western region were higher than those in the eastern region and this trend coincided with that of the particle fluxes in the surface layer, the export production in the surface layer was assumed to influence the particle flux in the intermediate layer of the northwestern North Pacific.  相似文献   

9.
The heavy metal contents and the contamination levels of the surface sediments of the Wuding River, northern China, were investigated. Heavy metal concentration ranged in μg g−1: 50.15–71.91 for Cr, 408.1–442.9 for Mn, 20.11–43.59 for Ni, 17.51–20.1 for Cu, 68.32–89.57 for Zn, 0.2–0.38 for Cd and 15.08–16.14 for Pb in the Wuding River sediments. The enrichment factor (EF) and the geo-accumulation index (Igeo) demonstrated that the sediments of the Wuding River had been polluted by Cd, Cr and Ni, which mainly originated from anthropogenic sources, whereas the sediments had not been polluted by Zn, Pb, Cu and Mn, which were derived from the crust. In addition, the assessment results of EF and Igeo suggested that the sediments of the Wuding River was “moderately” polluted by Cd and “unpolluted to moderately” polluted by Cr and Ni. The elevated urban sewage discharges and agriculture fertilizers usage in river basin are the anthropogenic sources of these heavy metals in river.  相似文献   

10.
This paper deals with the distribution of 210Po in the river bank soil samples of three major rivers namely Bharathapuzha, Periyar and Kallada river of Kerala. The dependence of 210Po activity on organic matter content in the samples was also studied. The soil samples were collected and analyzed for 210Po radionuclide using standard radiochemical analytical method. Activity of 210Po increases with increase in organic matter content in samples. Along the Bharathapuzha river bank the 210Po activity ranges from 2.96 to 12.48 Bq kg−1 with mean 5.62 Bq kg−1. The organic matter percentage in the samples ranges from 0.4 to 2.8 and a good correlation with correlation coefficient 0.9 was found between activity and organic matter percentage. In the Periyar river environs 210Po activity ranges from 3.47 to 13.39 Bq kg−1 with mean value 9.27 Bq kg−1. Organic matter percentage in these samples ranges from 1.20 to 4.10 and the correlation coefficient between 210Po activity and organic matter percentage was found to be 0.8 In the Kallada river bank soil samples 210Po activity ranges from 4.46 to 6.45 Bq kg−1. The organic matter percentage ranges from 1.4 to 3. The correlation coefficient between 210Po activity and organic matter percentage in the samples was found to be 0.9.  相似文献   

11.
An increasing interest in determination of various macro- and microelements in medicinal plants has been observed. The majority of studies are carried out using one mineralization method without any optimization. The present study demonstrates that changes in mineralization parameters can significantly affect the recovery of the elements determined. In the study, the dried plant material was mineralized in 12 ways and iron (Fe), copper (Cu), zinc (Zn), nickel (Ni) and manganese (Mn) levels were determined. The samples were mineralized in the dry or open microwave mode as well as 10 closed microwave modes. The influence of acid amounts, irradiation power and time, addition of hydrogen peroxide and perfluoric acid was examined. All parameters were shown to be critical — good efficiency was observed with larger amounts of acid. The determined content varied significantly in the same sample and were in the ranges (ug g−1): 46–136 (Fe), 1.4–11.8 (Cu), 4.0–11.3 (Ni), 15.4–53.8 (Zn) and 9.5–67.6 (Mn). Increased irradiation resulted in the loss of copper and zinc and better recovery of nickel. The results demonstrate that such determinations should include the mineralization optimization step.   相似文献   

12.
The preparation of new Certified Reference Materials (CRMs) of antarctic matrices forms the backbone of an ongoing project in the framework of the Italian National Program for Antarctic Research. The first CRM of this kind (MURST-ISS-A1 Antarctic Marine Sediment) is already available. The second phase focuses on the certification of antarctic krill, a small shrimp extremely abundant in the Southern Ocean. The total mass of krill available for this purpose is approximately 44 kg and results from the combination of three different catches (Ross Sea, Marguerite Bay and Livingston Island, respectively). The quantification of the following elements in the raw mass appears to be affordable by current analytical techniques, values being in the range of (in μg/g) 0.11–0.30 for As, 0.03–0.12 for Cd, 0.06–0.23 for Cr, 6.1–21 for Cu, 5.7–7.6 for Fe, 0.005–0.008 for Hg, 0.7–1.2 for Mn, 0.013– 0.077 for Ni, 0.04–0.57 for Pb and 12–16 for Zn. On the other hand, the average values ascertained in freeze-dried krill are as a rule one order of magnitude higher, i.e., (in μg/g), 3.2 for As, 0.6 for Cd, 1.8 for Cr, 75 for Cu, 61 for Fe, 0.025 for Hg, 4.6 for Mn, 0.7 for Ni, 2.1 for Pb and 81 for Zn. Information on the pretreatment of krill and details on the planned certification campaign are also given. Received: 10 June 1997 / Revised: 24 September 1997 / Accepted: 28 September 1997  相似文献   

13.
An improved method is proposed to determine the content of 210Pb in lead using 210Po measured by alpha-ray spectrometry. This improved method, which is based on radiochemical separation by DDTC–toluene extraction, employs EDTA and citrate as masking reagents for the lead ions. To selectively extract polonium from an alkaline solution, the pH dependency was examined using a liquid scintillation counting method. And pH 9 was chosen as an extraction condition. Then 210Po was electrodeposited on a stainless steel disk, and the chemical recovery was followed by 209Po tracer. The effectiveness of the new method was validated by the agreement with the analytical results from five samples as determined by gamma-ray spectrometry.  相似文献   

14.
Summary The element contents of Cd, Cu, Hg, Ni, Pb and Zn of three types of soil were certified. The preparation, homogeneity and stability are reported. The certified contents as well as values for Co, Cr, Mn and Se and for the aqua regia soluble contents Cd, Cr, Cu, Mn, Ni, Pb and Zn are given.
Zertifizierung von Schwermetallspuren (Cd, Cu, Hg, Ni, Pb und Zn) in drei Bodenproben
Zusammenfassung In drei verschiedenen Bodenproben wurden die Elementgehalte an Cd, Cu, Hg, Ni, Pb und Zn zertifiziert. Es wird berichtet über die Bereitung, Homogenität und Stabilität. Die zertifizierten Gehalte sowie der Gehalt an Cr, Co, Mn und Se und der Gehalt an königswasserlöslichem Cd, Cr, Cu, Mn, Ni, Pb und Zn werden angegeben.
  相似文献   

15.
To estimate the dietary intakes of 210Pb and 210Po for the Japanese adults and their annual effective doses, 210Pb and 210Po were measured for 240 daily diet samples collected at two locations of Ishikawa Prefecture in Japan over three years by duplicate portion studies. No appreciable differences in intake rates of 210Pb and 210Po and their 210Po/210Pb ratios were seen among the years in each district, and between the two districts. The intake rates evaluated using 240 diet samples were 0.20 Bq/d/p for 210Pb and 0.61 Bq/d/p for 210Po as a median, respectively. Annual effective doses of 210Pb and 210Po for Japanese adults were estimated to be 0.050 and 0.053 mSv/y, respectively.  相似文献   

16.
For the first time, a radiological study for the dissolved 238U, 234U, 210Pb and 210Po was held in major Greek rivers across the country. 234U/238U activity ratios are above one in all samples and 210Po/210Pb activity ratios are respectively below the unit indicating the disequilibrium in the samples. Quite satisfactory correlations were observed among 234U and 238U as well as among 210Po and 210Pb values. Uranium isotopes were separated by ion exchange and electroplated on stainless steel plates. 210Po was spontaneously deposited on nickel plates, while 210Pb was indirectly determined through the ingrowth of 210Po. The sources were measured by a-spectrometry.  相似文献   

17.
Summary The element contents of Cd, Co, Cu, Mn, Hg, Ni, Pb and Zn of three different types of sewage sludge were certified. The preparation, the homogeneity and the stability are reported. The certified contents as well as values for Cr and Se and for the aqua regia soluble contents of Cd, Cr, Co, Cu, Mn, Ni, Pb and Zn are given.
Zertifizierung von Schwermetallspuren (Cd, Co, Cu, Mn, Hg, Ni, Pb und Zn) in drei Klärschlammproben
Zusammenfassung In drei verschiedenen Klärschlammproben wurden die Elementgehalte an Cd, Co, Cu, Mn, Hg, Ni, Pb und Zn zertifiziert. Es wird berichtet über die Herstellung, Homogenität und Stabilität. Die zertifizierten Gehalte sowie der Gehalt von Cr, Se und der Gehalt an königswasserlöslichem Cd, Cr, Co, Cu, Mn, Ni, Pb und Zn werden angegeben.
  相似文献   

18.
Zusammenfassung Zur Anreicherung von Spurenelementen aus Lösungen reinster Thalliumpräparate wird die Matrix Thallium als TlJ ausgefällt. Dabei bleiben die Spuren Mg, Zn, Al, Ga, In, Fe, Co, Ni, Mn, Sn, La, Ce, Th und U quantitativ in Lösung, während Bi, Cu, Pb und Cd sowie die Edelmetalle Ag, Hg, Pd, Au und Pt vom Niederschlag mitgerissen werden. Die Adsorption der für die Reinheitsprüfung des Thalliums wichtigen Elemente Bi, Cu, Pb und Cd kann verhindert werden, wenn sie mit Hilfe von ÄDTA in Komplexanionen übergeführt werden. Als Fällungsmittel wird NaJ verwendet. Zur spektrochemischen Bestimmung werden Pb, Cd, Bi, Ni, Co und In als DDTC-Komplexe mit Chloroform extrahiert. Nach Zusatz einer Mischung von Lithiumcarbonat-Kohle und den Referenzelementen Sn und Pd wird der Eindampfrückstand im Gleichstrombogen analysiert. Cu und Fe werden photometrisch bestimmt.
Enrichment and spectrochemical determination of trace elements in high-purity thallium preparations
For the enrichment of trace elements in solutions of high-purity thallium samples, thallium is precipitated in form of TlI. In this process the noble metals Ag, Hg, Pd, Au, Pt and also Bi, Cu, Pb and Cd will be co-precipitated, whereas many other elements (Mg, Zn, Al, Ga, In, Fe, Co, Ni, Mn, Sn, La, Ce, Th, U) will remain completely in solution. The adsorption of the four elements Bi, Cu, Pb, Cd, which are important for the purity control of thallium compounds, can be prevented, if they are complexed with EDTA to form complex anions. The precipitating reagent is NaI. For the spectrochemical determination of Pb, Cd, Bi, Ni, Co, and In, the trace elements are extracted as DDTC complexes with chloroform. After the addition of a mixture of Li2CO3, carbon, and the reference elements Sn and Pd, the sample is analysed, using the d.c. arc. Cu and Fe are determined spectrophotometrically.


Wir danken dem Fonds der chemischen Industrie für die finanzielle Unterstützung dieser Arbeit.  相似文献   

19.
Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) 3-methylglutarates were prepared as solids with general formula MC6 H8 O4 ×n H2 O, where n =0–8. Their solubilities in water at 293 K were determined (7.0×10−2 −4.2×10−3 mol dm−3 ). The IR spectra were recorded and thermal decomposition in air was investigated. The IR spectra suggest that the carboxylate groups are mono- or bidentate. During heating the hydrated complexes lose some water molecules in one (Mn, Co, Ni, Cu) or two steps (Cd) and then mono- (Cu) or dihydrates (Mn, Co, Ni) decompose to oxides directly (Mn, Cu, Co) or with intermediate formation of free metals (Co, Ni). Anhydrous Zn(II) complex decomposes directly to the oxide ZnO. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

20.
Divalent metal complexes of N,N′-bis(4-imidazolymethyl)etylenediamine (EMI) have been studied using potentiometric and spectroscopic techniques (UV-Vis and NMR methods) in aqueous 0.1 mol⋅L−1 KCl supporting electrolyte at 25 °C. Final models and overall stability constants for the complexes of Ca(II), Cd(II), Co(II), Cu(II), Mg(II), Mn(II), Ni(II), Pb(II) and Zn(II) have been established by potentiometry for all M(II)–EMI systems, except for Co(II)–EMI. The data revealed that EMI forms ML complexes with all M(II)–EMI systems, which is the dominant species over a wide range of pH except for the Ca(II)–EMI and Mg(II)–EMI systems. Formation of the MnHL complex was also found for Mn(II)–EMI solutions. In addition, the UV-Vis and 1H NMR results allowed us establish the coordination modes for the metal complexes between EMI with Cd(II), Cu(II), Ni(II) and Zn(II).  相似文献   

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