共查询到20条相似文献,搜索用时 0 毫秒
1.
随着核能事业的发展,高放废物的处理和处置问题日益突出.其中,研究高放废物在环境介质中的吸附、扩散和迁移行为是获取放射性核素对周围环境和人群健康影响的基础参数的最重要和最直接的途径.近年来,人们利用已有的实验数据及核素的基础热力学和动力学数据,附以相应的数学模型,建立了一些地球化学模拟软件,用于分析核素在地质介质中可能发生的连续性和长期性变化.目前,国内外常用的地球化学模拟软件有十多种.本文从热力学平衡计算原理、种态分布计算方法和表面配位模型假设等几个方面对地球化学模拟软件进行了简要介绍,对近年来地球化学模拟软件在核素种态分布计算和表面配位模型模拟两方面的应用进行了举例分析,并以Ca-U-CO3配合物为例,说明完备的热力学数据对地球化学模拟软件发展的重要性,以期促进我国地球化学模型的应用和发展. 相似文献
2.
Li Honghui Wang Ju Mao Liang Zhao Shuaiwei Jia Meilan Liu Yuchen Huang Shulong 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(6):2573-2581
Journal of Radioanalytical and Nuclear Chemistry - A safety assessment was conducted for Beishan region of Gansu, China, the results show that Se-79 and Cs-135 are the key nuclides released in the... 相似文献
3.
Tatsuya Suzuki Maiko Tanaka Yasuyuki Ikeda Shin-ichi Koyama 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(1):289-292
The adsorption behaviors of trivalent actinides and lanthanides on pyridine resin in lithium chloride aqueous solution were investigated. The adsorbed amounts of lanthanides and the degree of mutual separation of lanthanides increased with an increase in the concentration of lithium chloride in aqueous solution. The group separation of the trivalent actinides and lanthanides was observed. This separation phenomenon is similar in a hydrochloric acid solution. However, the adsorption behavior of lanthanides in lithium chloride is different from their behavior in a hydrochloric acid solution. This fact shows that the adsorption mechanisms of lanthanides in a lithium chloride aqueous solution and in a hydrochloric acid solution are different; the adsorption mechanisms are attributed to the ion exchange in a hydrochloric acid solution, and to the complex formation with pyridine group in a lithium chloride solution. 相似文献
4.
This paper describes the technical issues involved in the development of a feasible solution toward permanent radioactive waste disposal. Recent progress on internationally collaborative research efforts concerning the multibarrier concept, in situ experiments, computer modeling and natural analogues are discussed. 相似文献
5.
Yan Dong Zuo Rui Ding Kuke Wang Tiejian Fan Li He Yingxue Jiang Xiaoyan 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(6):2679-2688
Journal of Radioanalytical and Nuclear Chemistry - A granite fracture filling material (FFM) collected from a candidate high-level radioactive waste (HLRW) geological disposal was used to evaluate... 相似文献
6.
N. Shinohara Y. Hatsukawa K. Hata N. Kohno M. Andoh H. H. Saleh W. S. Charlton T. A. Parish S. Raman 《Journal of Radioanalytical and Nuclear Chemistry》1999,239(3):631-638
For nuclear transmutation of minor actinides, delayed neutron emission measurement for241Am was carried out in thermal neutron irradiation location. The neutron capture cross sections of241Am were also measured radiochemically. The transmutation process of241Am in reactor is discussed by calculating the yields of minor actinides with the nuclear data measured in this study and the
evaluated values. The accelerator driven transmutation of minor actinides by high-flux neutrons from spallation reactions
is also presented. 相似文献
7.
《Journal of Inorganic and Nuclear Chemistry》1981,43(11):2935-2940
D.c. polarographic and cyclic voltammetric studies have been carried out on aqueous solutions (10−4−10−3 M) of 249Cf, Sm and Gd. From the present data and the established electrochemical behavior of Sm and Gd, it can be inferred that Cf(III) is reduced in two steps at the mercury-drop electrode, first to Cf(II), followed by the Cf(II) being reduced to Cf(Hg). The potentials for the two electrochemical steps are −1.47 and −1.68V vs NHE, respectively. 相似文献
8.
A six-day workshop, developed for providing information on sources and effects of radioactive waste disposal to the general public, is described. The materials were used successfully with a group representing the general public. An extension of the workshop for high school and junior high school science teachers is discussed. *** DIRECT SUPPORT *** A0653119 00009 相似文献
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Treatment of an aqueous radioactive waste solution to remove radium prior to discharge was conducted at a laboratory scale. The actual solution is mainly composed of combined radium (226Ra and228Ra) with high concentrations of manganese, iron and calcium, which are present as chlorides in dilute hydrochloric acid. Direct precipitation by sulfate anions was selected to be the more viable treatment technique. Sulfate anion concentration, free acidity, temperature and aging of the sulfate precipitate in the supernate prior to filtration are factors that were investigated for their effect on the separation efficiency. The data obtained are discussed in detail. 相似文献
11.
Shin-Ichi Ishikawa Kyozo Suyama Isamu Satoh 《Applied biochemistry and biotechnology》1999,78(1-3):521-533
Removal of radioactive elements from the effluent and waste aqueous solutions is an important problem. In previous laboratory
batch experiments, hen egg-shell membrane (ESM) was stable as an insoluble protein and was very capable of binding heavy metal
ions from aqueous solution. Batch laboratory pH profile, time dependency, and capacity experiments were performed to determine
the binding of uranium (U) and thorium (Th) to ESM. Batch pH profile experiments indicated that the optimum pH for binding
these actinides was approx 6.0 (U) or 3.0 (Th). The adsorption isotherms were developed at pH 5.0 (U) or 3.0 (Th) at 25°C,
and the adsorption equilibrium data fitted both Langmuir and Freundlich models. The maximum uptakes by the Langmuir model
were about 240 mg U/g and 60 mg Th/g dry weight ESM. In addition, their adsorption capacities increased as salt concentration
increased. ESM could also accumulate uranium from dilute aqueous solution by adjusting to the optimum pH. These results showed
that ESM was effective for removing actinides from solution and would be useful in filtration technology to remove actinides
from aqueous solution.
S.-I. Ishikawa is a research fellow at the Japan Society for the Promotion of Science. 相似文献
12.
Utilization of Slovak bentonites in deposition of high-level radioactive waste and spent nuclear fuel 总被引:2,自引:0,他引:2
Michal Galambo? Ol��ga Rosskopfov�� Jana Kuf?��kov�� Pavol Rajec 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(3):765-777
The basic strategic aims in the field of managing high-level radioactive waste and liquidation of nuclear power plants are all contained in the Energy policy of the Slovak Republic. Its aim is to resolve the concept of the backside of the nuclear energetics fuel cycle??long-term deposition of high-level radioactive waste and spent nuclear fuel (SNF). The most important form of high-level radioactive waste and SNF long-term deposition is their deposition in deep geological formations created by natural as well as engineering barriers used to isolate the long-lived radionuclides from the biosphere. The basic components of these barriers are clays, of which bentonite is generally referred to as the most suitable clay material. There are a few significant bentonite deposits in the Slovak Republic: Jel?ový potok, Kopernica, Lastovce, Lieskovec, Dolná Ves. The review article summarizes the information on geotechnical properties of Slovak bentonites published up-to-date, which is inevitable to know for the intention of their use. It highlights the advantages and shows drawbacks of five Slovak deposits. It suggests further research direction, to draw a thorough hydraulical, microbial and radiation profile of Slovak bentonites. 相似文献
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14.
Aqueous solutions of dimethyl sulfoxide (DMSO) and acetone have been investigated using neutron diffraction augmented with isotopic substitution and empirical potential structure refinement computer simulations. Each solute has been measured at two concentrations-1:20 and 1:2 solute:water mole ratios. At both concentrations for each solute, the tetrahedral hydrogen bonding network of water is largely unperturbed, though the total water molecule coordination number is reduced in the higher 1:2 concentrations. With higher concentrations of acetone, water tends to segregate into clusters, while in higher concentrations of DMSO the present study reconfirms that the structure of the liquid is dominated by DMSO-water interactions. This result may have implications for the highly nonideal behavior observed in the thermodynamic functions for 1:2 DMSO-water solutions. 相似文献
15.
Watanabe Sou Senzaki Tatsuya Shibata Atsuhiro Nomura Kazunori Takeuchi Masayuki Nakatani Kiyoharu Matsuura Haruaki Horiuchi Yusuke Arai Tsuyoshi 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(3):1273-1277
Journal of Radioanalytical and Nuclear Chemistry - Extraction chromatography flow-sheet employing octyl(phenyl)-N,N-diisobutylcarbonoylmethylphosphine oxide and bis(2-ethylhexyl) hydrogen phosphate... 相似文献
16.
Reheim N. A. Abdel Geleel M. Abdel Mohammed Ashraf. A. Atta E. R. Elsawy Emtithal A. Tawfik Amaal 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(2):455-465
Journal of Radioanalytical and Nuclear Chemistry - The current work aims at the preparation and characterization of novel composite materials of acrylic acid/charcoal/montmorillonite (MMT) (PAACM... 相似文献
17.
I. A. Ivanov V. M. Sedov A. N. Gulin V. M. Shatkov E. A. Shashukov 《Journal of Radioanalytical and Nuclear Chemistry》1991,147(1):191-195
Diffusion coefficients of radionuclides237Np,239Pu and241Am in simulated alumina phosphate and alumina borosilicate glasses at temperatures lower than their transformation temperature were determined. Actinides are known to be the least mobile elements. In particular, the diffusion coefficients of actinides in alumina phosphate glasses at 673 K are about 10–18 m2·s–1, and in alumina borosilicate at 773 K about 10–19 m2·s–1. It is shown that crystallization of glasses leads to increasing237Np diffusion mobility. It is also shown that a rather small quantity of water absorbed by a crystallized alumina phosphate glass in tensifies low-temperature migration of237Np. 相似文献
18.
Self-diffusion coefficients D of the trivalent aquo ion Cm3+ have been determined in aqueous Nd(ClO4)3?HClO4 solutions (pH 2.5) at 25°C, by the open-end capillary method (O. E. C. M.). The variation of D versus the square root of the concentration of inactive solution is an exponential form in the studied range of concentration. The limiting value D0 at zero ionic strength is 6.0·10?6 cm2·s?1. The curve \(D = f(\sqrt c )\) relating to Cm3+ can be compared to those of241Am3+ and153Gd3+ obtained under similar conditions. We find a similar ionic structure of Cm3+ with Am3+ and Gd3+. They have the same hydration as a tripositive of 5f and 4f ions in the absence of hydrolysis, complexing, or pairing at pH 2.5. The present study contributes to show the analogy of the solvation structure of trivalent actinide ions in aqueous solution at pH 2.5 with that of the trivalent lanthanide ions as a help for predicting the thermodynamic properties. 相似文献
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Wang C. Myshkin V. F. Khan V. A. Panamareva A. N. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3401-3426
Journal of Radioanalytical and Nuclear Chemistry - Clay is a widespread natural mineral. The review considers physical and chemical properties of clay minerals which are important in terms of... 相似文献