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1.
There is a need for fast, reliable methods for the determination of actinides and 89/90Sr analysis on environmental and bioassay samples in response to an emergency radiological incident. The Savannah River Site (SRS) Environmental Laboratory participated in the National Institute of Standards and Technology Radiochemistry Intercomparison Program (NRIP-06) and analyzed water and urine samples within 8 hours of receipt. The SRS Environmental Laboratory was the only lab that participated in the program that analyzed these samples for both actinides and 89/90Sr within an eight hour turnaround time. A rapid actinide and 89/90Sr separation method was used for both urine and water samples. This method uses stacked TEVA Resin®, TRU Resin® and Sr-Resin® cartridges from Eichrom Technologies (Darien, IL, USA) that allows the rapid separation of plutonium (Pu), neptunium (Np), uranium (U), and americium (Am), curium (Cm) and thorium (Th) using a single multi-stage column combined with alpha-spectrometry. Vacuum box cartridge technology with rapid flow rates was used to minimize sample preparation time. This paper discusses the technology and conditions employed for both water and urine samples and presents the SRS performance data on the NRIP-06 samples.  相似文献   

2.
Summary As a consequence of the high toxicity of organochlorine pesticides their presence in water for human consumption is limited by legislation. To determine these compounds at trace levels, an extraction procedure and a highly sensitive analytical technique is necessary. In this work we have used laminar disks for the solid-phase extraction of 21 organochlorine pesticides from water. The analytical technique selected is gas chromatography with electron-capture detection. A solid-phase extraction procedure is proposed, and some problems has been encountered. Low recovery of some pesticides has been obtained, because of their adsorption by the walls of containers. To prevent this adsorption, addition of 20% methanol before the sampling step is proposed. Adsorption of pesticides by the organic matter present in water samples was also observed. Pesticides can be adsorbed by the membrane filters usually used to remove suspended particulate matter from water samples. Different kinds of filters have been tested, and the occurrence of the problem has been confirmed. The use of laminar disks in this work has overcome this problem.  相似文献   

3.
This paper describes a simple approach to determine gold nanoparticles in liver and river water samples. The method of purification of nanoparticles from the matrix is based on the stabilization of gold nanoparticles with a cationic surfactant followed by a microliquid-liquid extraction in ionic liquid. Finally, the extracted nanoparticles can be analysed by UV/Vis detection or Raman spectroscopy. The precision of the proposed method for the analysis of liver tissue and river water samples was 9.7% and 18% respectively for UV/Vis analysis. The sensitivity was 1.17 × 10(-12) M for the analysis of 3 mL of liver homogenate or river water sample.  相似文献   

4.
偶合化学发光法测定环境水样中的痕量亚硝酸根   总被引:9,自引:0,他引:9  
将亚硝酸盐在酸性条件下氧化亚铁氰化钾为铁氰化钾的反应 ,和尿酸 铁氰化钾 鲁米诺化学发光反应偶合一起 ,建立了一种间接测定亚硝酸根离子的新方法。讨论了酸度、反应物浓度、干扰离子等因素的影响。方法的检出限为5 .0× 1 0 - 1 1 g/mL ,对环境水样样品进行了平行测定 (n =1 1 ) ,其相对标准偏差为1 .8%~ 3 2 % ,线性范围为 1 .0× 1 0 - 9g/mL~ 1 .0× 1 0 - 5g/mL ,回收率为 94.3%~ 1 0 5 3%。  相似文献   

5.
We have tested screening and response surface experimental designs to optimise the solid-phase microextraction (SPME) of the widely used herbicide alachlor. Extraction time and sample volume were the only statistically significant factors from those studied. In the final optimised conditions the procedure was applied to the SPME-HPLC analysis of alachlor in spiked water samples with excellent figures of merit.  相似文献   

6.
A new highly sensitive and selective chromogenic reagent, p-carboxyphenylfluorone (p-CPF), was studied for spectrophotometric determination of trace molybdenum. In 0.36 mol L(-1)phosphoric acid medium, p-CPF reacts with molybdenum(VI) to form a 1:3 red complex, which has a sensitive absorption peak at 531 nm. Under optimal conditions, the reaction of molybdenum(VI) with p-CPF completed rapidly and absorbance remains almost constant for at least 24 h. Molybdenum(VI) obeyed Beer's law in the range 0-2.0 microg mL(-1); the apparent molar absorption coefficient, Sandell's sensitivity and the limit of detection were found to be 1.03 x 10(5) L mol(-1) cm(-1), 1.028 ng cm(-2)and 0.73 ng mL(-1) respectively; the effect of various foreign ions were examined in detail. It was found that most coexisting ions can be tolerated in considerable amounts, especially 800 mg of Mn(II), 200 mg of Mg(II), Fe(II), Co(III), Ni(II) and Cd(II), 50 mg of Ca(II) and Al(III), 25 mg of Cu(II) and Fe(III), 10 mg of Hg (II), La(III), Bi(III), Pb(II) and Zn(II) don't interfere with the determination of molybdenum(VI). The proposed method is very simple, sensitive and selective, it has been applied to determine molybdenum in vegetable and food samples with a very high precision and accuracy. Moreover, the synthesis of the reagent and the conditions of the colour reaction were also studied in detail.  相似文献   

7.
Summary The measurement of radium isotopes in natural waters is important for oceanographic studies and for public health reasons. Radium-226 (T1/2 = 1620 y) is one of the most toxic of the long-lived alpha-emitters present in the environment due to its long life and its tendency to concentrate in bones, which increases the internal radiation dose of individuals. The analysis of 226Ra and 228Ra in natural waters can be tedious and time-consuming. Different sample preparation methods are often required to prepare 226Ra and 228Ra for separate analyses. A rapid method has been developed at the Savannah River Environmental Laboratory that effectively separates both 226Ra and 228Ra (via 228Ac) for assay. This method uses MnO2 Resin from Eichrom Technologies (Darien, IL, USA) to preconcentrate 226Ra and 228Ra rapidly from water samples, along with 133Ba tracer. DGA Resinò (Eichrom) and Ln-Resinò (Eichrom) are employed in tandem to prepare 226Ra for assay by alpha-spectrometry and to determine 228Ra via the measurement of 228Ac by gas proportional counting. After preconcentration, the manganese dioxide is dissolved from the resin and passed through stacked Ln-Resin-DGA Resin cartridges that remove uranium and thorium interferences and retain 228Ac on DGA Resin. The eluate that passed through this column is evaporated, redissolved in a lower acidity and passed through Ln-Resin again to further remove interferences before performing a barium sulfate microprecipitation. The 228Ac is stripped from the resin, collected using cerium fluoride microprecipitation and counted by gas proportional counting. By using vacuum box cartridge technology with rapid flow rates, sample preparation time is minimized.  相似文献   

8.
Summary Mono-standard neutron-activation analysis of large-volume water samples without preliminary chemistry is applied to the multielement determination of trace inorganic species in pure water, river water, urban effluent, etc. The accuracy, precision and sensitivity have been assessed by analysing a standard reference material, a water sample from a round-robin analysis and pure waters. The method is applied to investigate the behaviour of trace inorganic species in the course of the cleaning process in an urban sewage treatment plant. The distribution of the elements in the effluents and stably suspended materials has been systematically analysed and the behaviour of the elements in the system discussed.
Multielementanalyse anorganischer Spurenelemente in grovolumigen Wasserproben mit der Mono-Standard-Neutronen-Aktivierungs-Analyse
Zusammenfassung Die Mono-Standard-Neutronen-Aktivierungs-Analyse großvolumiger Wasserproben ohne chemische Vorbehandlung wird zur Bestimmung anorganischer Spurenelemente in reinem Wasser, Flußwasser, Abwasser usw. eingesetzt. Die Richtigkeit, Genauigkeit und Empfindlichkeit der Methode wurden durch Analysen von Standard-Referenz-Material, eine Ringanalyse einer Wasserprobe und reinen Wassers überprüft. Die Methode wird zur Untersuchung des Verhaltens anorganischer Spurenelemente während des Reinigungsprozesses in einer Kläranlage angewandt. Die Verteilung der Elemente zwischen dem Abwasser und dem stabil suspendierten Schwebstoff wurde systematisch analysiert und das Verhalten der Elemente in dem System diskutiert.


Presented at the 8th International Microchemical Symposium, Graz, August 25–30, 1980.  相似文献   

9.
Our aim was to discover a method of separating zirconium(IV) and uranium(VI) from solutions. It is known that Zr(IV) and U(VI) are effectively extracted by tertiary amines from weak acidic sulfate solutions but the possibility of extraction decreases with increasing acidity. The transition from tertiary amine to primary amine Primene JMT enables the extraction of Zr also from more acidic solution. If both Zr and U are present in an aqueous solution, Zr is extracted preferentially and only the free part of the amine can convert uranium to an extract. The separation described below was carried out by preferentially stripping zirconium from the organic phase. The application of nitrate solution (2M HNO3) to eliminate Zr from the solvent was tested. This method does not demand any special regeneration of the extraction agent and the amine nitrate, formed in the organic phase, can be used for further extraction of Zr without modification. Using this method of separation, a solution for producing pure ZrOCl2·8H2O was obtained.  相似文献   

10.
Y Kusaka  H Tsuji  S Imai  S Ohmori 《Radioisotopes》1979,28(3):139-144
Analytical values of trace elements in sea water samples have been fluctuated according to the sampling locations, the analytical procedures and so on. It is very important in marine chemistry to elucidate the cause of such concentration variations. This report is the analytical results of the samples obtained in the Pacific Ocean, the Indian Ocean and the Sea of Japan, by means of neutron activation analysis. As the preconcentration, APDC-chelate extraction and freeze-drying were adopted. The specimens obtained by this extraction from 500 or 800 ml samples were irradiated by KUR reactor for 1 min, 1 hr to 10 hrs and the gamma-ray spectrometry with a Ge(Li) detector was used for the determination of V, Mn, Cu, Zn, U, Fe, Co, Ni, Ag, Sb and Au. By about 80 hrs irradiation of the specimens obtained by freeze-drying from 20 ml samples and their gamma-ray spectrometry, Sc, Cr, Fe, Co, Zn, Rb, Sr, Ag, Sb and Cs were determined. The former procedure gives concentrations of elements in species reactable with APDC, but the latter method shows entire concentrations of the elements in the sea water samples. Some considerations on the analytical values and the comparisons of the both methods are described.  相似文献   

11.
The short-term (up to 24 h) stability of estuarine water with high (22%?) and low (<21%?) salinity, stored unacidified in polythene containers prior to filtration, preservation and determination of dissolved trace metals, was assessed. For the-salinity sample a massive (140%) increase in copper concentration was observed, indicating desorption from the particulate phase; a similar, although less pronounced (11%) effect was found for the high-salinity sample, Evidence was also obtained for a significant loss (30%) of lead from a pre-filtered low-salinity sample, suggesting appreciable adsorption to the container walls. For cadmium and nickel, no substantial changes in concentration were observed.  相似文献   

12.
A new rapid method for the determination of 210Po in water samples has been developed at the Savannah River National Laboratory (SRNL) that can be used for emergency response or routine water analyses. If a radiological dispersive device event or a radiological attack associated with drinking water supplies occurs, there will be an urgent need for rapid analyses of water samples, including drinking water, ground water and other water effluents. Current analytical methods for the assay of 210Po in water samples have typically involved spontaneous auto-deposition of 210Po onto silver or other metal disks followed by counting by alpha spectrometry. The auto-deposition times range from 90 min to 24 h or more, at times with yields that may be less than desirable. If sample interferences are present, decreased yields and degraded alpha spectrums can occur due to unpredictable thickening in the deposited layer. Separation methods have focused on the use of Sr Resin?, often in combination with 210Pb analysis. A new rapid method for 210Po in water samples has been developed at the SRNL that utilizes a rapid calcium phosphate co-precipitation method, separation using DGA Resin® (N,N,N′,N′ tetraoctyldiglycolamide extractant-coated resin, Eichrom Technologies or Triskem-International), followed by rapid microprecipitation of 210Po using bismuth phosphate for counting by alpha spectrometry. This new method can be performed quickly with excellent removal of interferences, high chemical yields and very good alpha peak resolution, eliminating any potential problems with the alpha source preparation for emergency or routine samples. A rapid sequential separation method to separate 210Po and actinide isotopes was also developed. This new approach, rapid separation with DGA resin plus microprecipitation for alpha source preparation, is a significant advance in radiochemistry for the rapid determination of 210Po.  相似文献   

13.
A rapid method for determining traces of radiostrontium in milk and drinking water is described. The technique involves a batch treatment of the milk sample with a cation exchanger (DOWEX 50W X8) followed by a solvent extraction with a crown ether (DC18C6) and a precipitation of SrCO3. In the case of water, the strontium is extracted directly with the crown ether. The average separation yield is 74% for milk and 91% for water. The overall separation procedure takes about 8 hours. Activities as low as 0.03 Bq/1 can be determined with a low background GM-counter.  相似文献   

14.
Highly sensitive flow-injection chemiluminescence (CL) combined with molecularly imprinted solid-phase extraction (MISPE) has been used for determination of 2,4-dichlorophenol (2,4-DCP) in water samples. The molecularly imprinted polymer (MIP) for 2,4-DCP was prepared by non-covalent molecular imprinting methods, using 4-vinylpyridine (4-VP) and ethylene glycol dimethacrylate (EGDMA) as the monomer and cross-linker, respectively. 2,4-DCP could be selectively adsorbed by the MIP and the adsorbed 2,4-DCP was determined by its enhancing effect on the weak chemiluminescence reaction between potassium permanganate and luminol. The enhanced CL intensity was linear in the range from 1 × 10−7 to 2 × 10−5g mL−1. The LOD (S/N = 3) was 1.8 × 10−8g mL−1, and the relative standard deviation (RSD) was 3.0% (n = 11) for 1.4 × 10−6g mL−1. The proposed method had been successfully applied to the determination of 2,4-DCP in river water. Figure Effect of 4-VP content on the ultraviolet spectrum of 2,4-DCP in chloroform  相似文献   

15.
16.
在酸性条件下,利用间苯二酚能抑制罗丹明B和溴酸根反应速率的原理,联用顺序注射技术建立了非平衡态快速测定痕量间苯二酚的新方法.优化了顺序注射流路参数、试剂用量,考察了共存物的影响.在最佳条件下,该法测定间苯二酚的线性范围为0.20~3.00 μg/mL,检出限为0.09 μg/mL,每小时可测定40个样.  相似文献   

17.
Thermal neutron activation analysis and a large-volume high-resolution Ge(Li) gammaray spectrometer, connected on-line to a DEC PDP 8/L computer, have been used to measure the concentrations of Na, Sc, Cr, Fe, Co, Ni, Zn, As, Se, Br, Rb, Ag, Sb, Cs, W and Hg in some Italian subsurface water samples. The instrumental method requires neither a chemical separation technique nor a pre- or post-concentration of the trace elements to be detected. As a consequence, this method eliminates many inherent errors associated with chemical determinations. The technique is sensitive, precise and particularly suitable for routine analysis of many trace elements at both natural and pollution levels in water samples. The interferences due to fast neutron (n, p) and (n, α) reactions are not appreciable, with the only exception of the54Fe(n, p)54Mn and58Ni(n, p)58Co reactions. Losses of volatile, elements, e. g. As, Br and Hg, during irradiation proved to be negligible.  相似文献   

18.
Saline water samples from the Delaware Bay estuary were sampled, processed, and stored in a variety of ways to allow different methods of maintaining their integrity to be compared. Samples were processed onboard ship, immediately after collection, by extraction with ammonium pyrollidinedithiocarbamate in methyl isobutyl ketone. Duplicate samples were processed onshore after a variety of storage procedures. All samples were analyzed for copper and iron by atomic absorption spectrometry. Only samples filtered (<1 μm), acidified, and stored frozen gave extractable copper and iron results comparable with those for samples extracted immediately after collection. Cold storage with sample acidification in polyethylene containers appeared less satisfactory. Organic extracts from samples processed onboard are best retained in all-Teflon containers pending complete digestion and analysis onshore. Unless clean (ultra-filtered air) conditions can be ensured onboard, the estuarine water samples are best returned in a filtered, acidified, and frozen condition for onshore processing.  相似文献   

19.
A simple and sensitive spectrophotometric method for determination of trace copper in water samples is proposed. In the presence of pH 4.6 HAc-NaAc buffer solution and surfactant polyethylene octyl phenyl ether (OP) medium, copper reacts with thiomichlersketone (TMK) to form a stable 1:4 complex. The complex Cu(II)-TMK-OP shows maximum absorbance at 500 nm with a molar absorptivity value of 5.7x10(4) l mol-1 cm-1. Beer's law is obeyed for copper concentrations in the range of 0-15 microg/25 ml. The average recovery of copper is between 95.8 and 106%. The method has been applied for determination of trace copper in different water samples with satisfactory results.  相似文献   

20.
The determination of As, Cd, Cr, Hg, Mn, Mo, Ni, Sb, and Se in two Nigerian rivers and two Nigerian harbor waters is described. The water samples were preconcentrated by both evaporation at room temperature and freeze evaporation under reduced pressure. Postirradiation chemical separation of sodium, using hydrated antimony pentoxide (HAP) in 6M HCl, and of bromine, by oxidation with KMnO4 and subsequent removal by extraction with CHCl3, was employed. The measured concentrations of these elements in some water samples, which are relatively high, can be attributed to local pollution.  相似文献   

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