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1.
In the context of the rapid development of the world’s nuclear power industry, it is vital to establish reliable and efficient radioanalytical methods to support sound environment and food radioactivity monitoring programs and a cost-effective waste management strategy. As one of the most import fission products generated during human nuclear activities, 90Sr has been widely determined based on different analytical techniques for routine radioactivity monitoring, emergency preparedness and radioactive waste management. Herein, we summarize and critically review analytical methods developed over the last few decades for the determination of 90Sr in environmental and biological samples. Approaches applied in different steps of the analysis including sample preparation, chemical separation and detection are systematically discussed. The recent development of modern materials for 90Sr concentration and advanced instruments for rapid 90Sr measurement are also addressed.  相似文献   

2.
Artificial long-lived radionuclides such as 90Sr and 239,240Pu have been long released into the environment by human nuclear activities, which have a profound impact on the ecological environment. It is of great significance to monitor the concentration of these radionuclides for environmental safety. This paper summarizes and critically discusses the separation and measurement methods for ultra-trace determination of 90Sr, 239Pu, and 240Pu in the environment. After selecting the measurement method, it is necessary to consider the decontamination of the interference from matrix elements and the key elements, and this involves the choice of the separation method. Measurement methods include both radiometric methods and non-radiometric methods. Radiometric methods, including alpha spectroscopy, liquid scintillation spectrometry, etc., are commonly used methods for measuring 239+240Pu and 90Sr. Mass spectrometry, as the representative of non-radiometric measurement methods, has been regarded as the most promising analytical method due to its high absolute sensitivity, low detection limit, and relatively short sample-analysis time. Through the comparison of various measurement methods, the future development trend of radionuclide measurement is prospected in this review. The fully automatic and rapid analysis method is a highlight. The new mass spectrometer with ultra-high sensitivity shows strong analytical capabilities for extremely low concentrations of 90Sr, 239Pu, and 240Pu, and it is expected to develop determination methods with higher sensitivity and lower detection limit.  相似文献   

3.
本文提出采用浓HNO_3-H_2O_2在低温常压下消化海洋生物样品的新方法,其特点是使用试剂简单,操作方便,节省时间,方法可靠。还介绍使用正交设计法试验了影响测铜灵敏度的主要因素。认为测定样品时,选择pH8.0~8.5、隐蔽剂10ml、铜试剂5 ml为最佳条件。本法还分别作了方法验证,结果良好。  相似文献   

4.
A porous composite material is described for determination of radionuclides in aquatic objects of the environment. Possibilities have been studied for the use of this material in monitoring of 90Sr content in natural waters. The composite is a scintillator with through pores, the surface of which is impregnated by a sorbent that is selective with respect to strontium. The structure of the material allows combination of two processes—concentrating the radionuclide and measuring its activity. Studies were carried out using both model systems based on reference radioactive solutions and samples of natural water contaminated with radionuclides. It is shown that the use of the proposed method for analysis of natural water allows determination in water of 4×10−2 Bq l−1 of 90Sr, which is by two orders of magnitude lower than its maximum acceptable concentration.  相似文献   

5.
The 87Sr/86Sr ratio of 39 Champagnes from six different brands, originating from the whole “Appellation d’Origine Contrôlée” (AOC) Champagne was analyzed to establish a possible relation with the geographical origin. Musts (i.e., grape juice) and base wines were also analyzed to study the evolution of the Sr isotopic ratio during the elaboration process of sparkling wine. The results demonstrate that there is a very homogeneous Sr isotopic ratio (87Sr/86Sr = 0.70812, n = 37) and a narrow span of variability (2σ = 0.00007, n = 37). Moreover, the Sr concentrations in Champagnes have also low variability, which can be in part explained by the homogeneity of the bedrock in the AOC Champagne. Measurements of the 87Sr/86Sr ratio from musts and base wines show that blending during Champagne production plays a major role in the limited variability observed. Further, the 87Sr/86Sr of the musts were closely linked to the 87Sr/86Sr ratio of the vineyard soil. It appears that the 87Sr/86Sr of the product does not change during the elaboration process, but its variability decreases throughout the process due to blending. Both the homogeneity of the soil composition in the Champagne AOC and the blending process during the wine making process with several blending steps at different stages account for the unique and stable Sr isotopic signature of the Champagne wines.  相似文献   

6.
Nuclear accidents occurred in latest years highlighted the difficulty to achieve, in a short time, the quantification of alpha and beta emitters. Indeed, most of the existing methods, though displaying excellent performances, can be very long, taking up to several weeks for some radioisotopes, such as 90Sr.  相似文献   

7.
石墨炉原子吸收法测定生物样品中的铊   总被引:1,自引:0,他引:1  
为建立测定生物样品中铊的石墨炉原子吸收法,通过微波消解,采用基本改进剂,改变石墨炉灰化温度等操作条件,提高了该法的准确度和精密度.结果表明,方法的线性范围为0~100 μg/L;检出限:血为0.10 mg/L;尿为0.02 mg/L;头发为0.20 mg/kg;回收率:血为83.1%~108%;尿为89.6%~105%...  相似文献   

8.
近二十年来,高分辨率27Al核磁共振(27Al NMR)广泛应用于研究Al(Ⅲ)离子水解过程,Al(Ⅲ)与环境生物配体的配位化学,环境与生物样品中铝含量测定和形态分析,监测铝在植物、动物、酵母菌等微生物中的转运过程,具有快速、直接、非破坏性等优点。27Al NMR不仅适用于高浓度的溶液,也可应用于低浓度(10-6mol·L-1)的实际环境、生物样品。应用27Al MASNMR可直接对固态样品中铝的存在状态和含量进行表征和测量。本文中对27Al NMR的应用进展作一评述,并总结了近二十年来文献发表的27Al化学位移数据。引用文献70余篇。  相似文献   

9.
Abstract

Organochlorine compounds such as polychlorinated biphenyls (PCBs) and chlorinated pesticides have been analysed in environmental biological samples using focused microwave-assisted extraction (FMW). The analytical procedure is presented and the results for two Standard Reference Materials, a cod liver oil and a freeze-dried mussel tissue, are reported. The average recoveries for the sum of the PCBs are between 93% and 106%, and for the sum of the chlorinated pesticides are between 109 to 115% for all the certified compounds analysed. The developped analytical procedure is highly reproducible with an average standard deviation of 8% for the sum of the PCBs and 9.7% for the sum of the chlorinated pesticides in the two matrices.  相似文献   

10.
We describe a precise and accurate method for the direct determination of the 87Sr/86Sr isotope ratio of bottled Sr-rich natural mineral drinking water using multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS). The method is validated by the comparative analysis of the same water with and without cation-exchange resin purification. The work indicates that isobarically interfering elements can be corrected for when 87Rb/86Sr < 0.05 (Rb/Sr < 0.015), and that the matrix elements (Ca, Mg, K and Na) have no significant effect on the accuracy of the Sr isotope data. The method is simple, rapid, eliminates sample preparation time, and avoids potential contamination during complicated sample-preparation procedures. Therefore, the high sample throughput inherent to the MC-ICP-MS can be fully exploited.  相似文献   

11.
采用加速溶剂萃取法(ASE)提取了海洋沉积物中的正构烷烃,并对ASE的萃取剂比例、萃取温度、静态萃取时间以及循环次数等实验条件进行优化。结果表明,当样品长碳链正构烷烃含量较高或需要检测长碳链正构烷烃含量时,可使用甲醇-二氯甲烷(1∶3)作为萃取剂;而甲醇-二氯甲烷(1∶9)适用于短碳链正构烷烃含量较高或需要检测短碳链正构烷烃含量的样品。加速溶剂萃取提取沉积物中正构烷烃的最佳条件为:萃取温度150℃,静态提取时间15 min,循环3次。在优化条件下,测定沉积物样品中正构烷烃的精密度除C15为20%外,其余为3%~14%,替代物回收率为84%~114%。相比于传统的索氏提取法,该方法的工作效率高、回收率高、精密度良好,适用于沉积物样品中正构烷烃的定量分析。  相似文献   

12.
本文评述了九十年代以来环境与生物样品分析中测铝的吸光光度和荧光光度分析方法的进展。对不同的方法进行了详尽的比较和讨论  相似文献   

13.
A systematic study was made of the optimum conditions for cadmium determination in biological samples by ICP-AES after extraction of the metal into methyl isobutyl ketone containing 1,5-bis[phenyl-(2-pyridyl)methylene]-thiocarbonohydrazide. The maximum volume ratio of aqueous to organic phase was 30 1 for a single-stage extraction of 99–100% of the metal ion. The detection limit was 0.3 ng/ml cadmium, and the calibration was linear from 0.4 to at least 150 ng/ml. No interferences from the elements commonly found in biological materials were observed. A precision of 2.5% (P = 0.05) at the 2 ng/ml level of the metal was achieved. The accuracy of the method was demonstrated by analysis of three standard reference materials, giving concentrations of 1.90 ± 0.43, 27.1 ± 1.4 and 2.63 ± 0.38 /g of cadmium, compared with the certified values of 2.20 ± 0.10, 26.3 ± 2.1, and 2.71 ± 0.15 g/g, respectively.  相似文献   

14.
Yttrium-90 (90Y) microspheres are widely used for the treatment of liver-dominant malignant tumors. They are infused via catheter into the hepatic artery branches supplying the tumor under fluoroscopic guidance based on pre-therapy angiography and Technetium-99m macroaggregated albumin (99mTc-MAA) planning. However, at present, these microspheres are suspended in radiolucent media such as dextrose 5% (D5) solution. In order to monitor the real-time implantation of the microspheres into the tumor, the 90Y microspheres could be suspended in omnipaque contrast for allowing visualization of the correct distribution of the microspheres into the tumor. The radiochemical purity of mixing 90Y-microspheres in various concentrations of omnipaque was investigated. The radiochemical purity and feasibility of mixing 99mTc-MAA with various concentrations of a standard contrast agent were also investigated. Results showed the radiochemical feasibility of mixing 90Y-microspheres with omnipaque is radiochemically acceptable for allowing real-time visualization of radioembolization under fluoroscopy.  相似文献   

15.
《Analytical letters》2012,45(8):449-456
Abstract

A rapid method for the gas chromatographic determination of barbiturates in biological samples has been developed. It consists of methylating the barbiturates with dimethyl sulfate, extracting the sample with n-heptane, and gas chromatographic analysis of the heptane extract on a SE-52 column. A preliminary study revealed that the method could be used for in vivo and/or in vitro determinations. Minimum detectable amounts of barbiturates were shown to be between 0.01 and 0.05 μg. An added advantage of the procedure is the lack of interference from other constituents which might be present in the analytical sample.  相似文献   

16.
Residues of Bay 93820 (isopropyl salicylate O-ester with O-methyl phosphoramidothioate) and its oxygen analog were determined in Coastal bermudagrass (Cynodyn dactylon (L.) Pers.), corn, and corn silage. The insecticide was applied in the field as aqueous sprays of an emulsifiable concentrate at rates of 6, 12, and 24 oz (active ingredient) per acre. Glass jar silage was made from 1-day post-field treatment corn. Residues were analyzed by gas chromatography by using a flame photometric detector sensitive to phosphorus; details of the analytical procedure are presented.

Residue levels of Bay 93820 in both corn and grass diminished to less than 1 ppm after 14 days of weathering in the field. Residues of the O-analog were lower than those of Bay 93820; however, they represented a much larger portion of the total residue than with any other O-analog-forming organophosphorus insecticide previously tested at our laboratory. Residues of Bay 93820 were essentially stable and persistent in corn silage, whereas the small amounts of O-analog tended to increase slightly.  相似文献   

17.
生物样品中儿茶酚胺类物质分析方法的研究进展   总被引:4,自引:0,他引:4  
顾群  石先哲  许国旺 《色谱》2007,25(4):457-462
儿茶酚胺是人体内重要的神经递质,血浆及尿中儿茶酚胺的浓度水平可用于诊断高血压、嗜铬细胞瘤及成神经细胞瘤等病症,因而准确测定人体生物样品中儿茶酚胺类物质代谢浓度的变化,在疾病的诊断和治疗中具有重要的意义。该文综述了人体液和组织中儿茶酚胺类物质的不同分析方法,包括高效液相色谱法、毛细管电泳法、质谱法、电化学法、化学发光法、荧光光度法等。  相似文献   

18.
 Cadmium is quantitatively retained by 2-nitroso-1-naphthol-4-sulfonic acid (nitroso-S) and tetradecyldimethylbenzylammonium chloride (TDBA) on microcrystalline naphthalene in the pH range 5.7–10.5 from a large volumes of aqueous solutions of various samples. After filtration, the solid mass consisting of cadmium complex and naphthalene is dissolved with 5 mL of dimethylformamide and the metal was determined by flame atomic absorption spectrometric. Cadmium complex can alternatively be quantitatively adsorbed on tetradecyldimethylbenzylammonium-naphthalene adsorbent packed in a column and determined similarly. About 25 ng of cadmium can be concentrated in a column from 500 mL of aqueous sample, where its concentration is as low as 0.05 ng/mL. Eight replicate determinations of 0.1 μg/mL of cadmium in final DMF solution gave a mean absorbance of 0.060 with a relative standard deviation of 1.8%. The sensitivity for 1% absorption was 7.3 ng/mL. The interference of a large number of anions and cations has been studied and the optimized conditions developed were utilized for the trace determination of cadmium in various alloys and biological samples. Correspondence: Department of Chemistry, Shahid Bahonar University, Kerman, Iran. e-mail: ma_taher@yahoo.com Received March 30, 2001; accepted January 18, 2002  相似文献   

19.
整体柱由于具有制备简单、内部结构均匀、重现性好、柱效较高和可进行快速分离等优点,在分离、催化等众多领域具有良好的应用前景。 本文综述了近年来有机聚合物整体柱在生物样品分离分析中的应用,并对其存在的问题和发展趋势进行了讨论。  相似文献   

20.
A novel arsine generator glass assembly is constructed and reported for the spectrophotometric determination and speciation of arsenic in real samples. In an arsine generator, sodium borohydride is added dropwise to the acidic sample solution and arsine thus formed is reacted with silver diethyldithiocarbamate (Ag‐DDTC) ‐ Tritron‐X (TX‐100) solution in pyridine to form a red coloured complex. The complex showed the absorption maximum at λmax 540 nm. The molar absorptivity of the method was found to be (1.55) × 104 L mole?1 cm?1 at this wavelength. The presence of non‐ionic surfactant, i.e. TX‐100 in the Ag‐DDTC solution, makes the method ≈ 3 times more sensitive than the conventional Ag‐DDTC method. Beer's law is obeyed in the concentration range of 0.05–2.80 mg L?1 of arsenic. The detection limit of the method was calculated to be 20 μg L?1 As. Speciation of arsenite from other forms of arsenic in sample solutions was carried out by extraction of arsenite with Pb‐DDTC in chloroform, followed by spectrophotometric determination. After arsenite separation the sample is used for the arsenate determination. Total arsenic was determined by acid decomposition of the same sample. The speciation data were found to be comparable (±2%) with ICP‐MS, with better precision (< 1%). The method has been successfully applied for the speciation of arsenic in drinking water and dust samples of arsenic affecting the Rajnandgaon district of Chhattisgarh, India, and urine and blood samples of patients with arsenical diseases. Concentration of total arsenic in tube‐well water of this area was 3–6 times more than the permissible limit. Dust samples contained less amounts of arsenic than the ground water.  相似文献   

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