摘要：
The aqueous extract from pomegranate peel (AEPP) was used to remove Microcystis aeruginosa. The flocculating properties of the natural flocculant from pomegranate peel to M. aeruginosa were investigated, which included the factors (i.e., the particle size of the pomegranate peel, the ratio of the material to the solvent, the addition of the natural flocculant, membrane pore size and density algae) influencing the removal of the algae from solutions. The removal efficiencies of algae were found to be significantly different with the pore sizes of the used membranes for filtration. The particulate matter in the aqueous extract had good effect of aid to the coagulation. In addition, the addition of AEPP pronouncedly influenced the algae removal, giving rise to the removal efficiency up to 13.99%, 26.55%, 63.84%. and 94.63% at the addition amount of 0.5, 0.7, 1.0, and 3.0 mL, respectively. Therefore, the natural flocculant from pomegranate peel was strongly confirmed to offer the favorable characteristics in M. aeruginosa removal.
摘要：
In order to develop and apply mixed iron- and sulfur-oxidizers in uranium bioleaching, the characteristics of a mixed iron- and sulfur-oxidizing consortium (Consortium ISO) were comparatively investigated versus an iron-oxidizing consortium (Consortium IO). The results showed, the Consortium ISO exerted stronger oxidative ability and acid-producing ability than Consortium IO did. The synergy of sulfur-oxidizers and iron-oxidizers could change the structure and properties of the passivation substance, and work positively for eliminating the accumulation of passivation substance. In the bioleaching process, the uranium bioleaching experiments showed the recovery percentage of uranium reached 99.5% with Consortium ISO, 6.3% more than that of Consortium IO.
摘要：
To explore a new evaluation method for spontaneous combustion tendency of different areas in sulfide ore heap, ore samples from a pyrite mine in China were taken as experimental materials, and the temperature variations of the measuring points of simulated ore heap were measured. Combined with wavelet transform and nonlinear parameters extraction, a new method for spontaneous combustion tendency of different areas in sulfide ore heap based on nonlinear parameters was proposed and its reliability was verified by field test. The results indicate that temperature field evolution of the simulated ore heap presents significant spatial difference during self-heating process. Area with the maximum increasing extent of temperature in sulfide ore heap changes notably with the proceeding of self-heating reaction. Self-heating of sulfide ore heap is a chaotic evolution process, which means that it is feasible to evaluate spontaneous combustion tendency of different areas by nonlinear analysis method. There is a relatively strong correlation between the maximum Lyapunov exponent and spontaneous combustion tendency with the correlation coefficient of 0.9792. Furthermore, the sort of the maximum Lyapunov exponent is consistent with that of spontaneous combustion tendency. Therefore, spontaneous combustion tendency of different areas in sulfide ore heap can be evaluated by means of the maximum Lyapunov exponent method.
摘要：
The biological effects of low-dose or low-dose-rate ionizing radiation on normal tissues has attracted attention. Based on previous research, we observed the morphology of liver tissues of C57BL/6J mice that received <50, 50-500, and 500-1000 muGy/h of 137Cs radiation for 180 d. We found that the pathological changes in liver tissues were more obvious as the irradiation dose rates increased. Additionally, differential protein expression in liver tissues was analyzed using a proteomics approach. Compared with the matched group in the 2D gel analysis of the irradiated groups, 69 proteins had >/= 1.5-fold changes in expression. Twenty-three proteins were selected based on >/=2.5-fold change in expression, and 22 of them were meaningful for bioinformatics and protein fingerprinting analysis. These molecules were relevant to cytoskeleton processes, cell metabolism, biological defense, mitochondrial damage, detoxification and tumorigenesis. The results from real-time PCR and western blot (WB) analyses showed that calreticulin (CRT) was up-regulated in the irradiated groups, which indicates that CRT may be relevant to stress reactions when mouse livers are exposed to low-dose irradiation and that low-dose-rate ionizing radiation may pose a cancer risk. The CRT protein can be a potential candidate for low-dose or low-dose-rate ionizing radiation early-warning biomarkers. However, the underlying mechanism requires further investigation.
通讯机构：
[Ding, De-xin] U;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.
关键词：
Gold bearing high arsenic sulphide concentrate;Microwave roasting;Water content;Iodide/iodine leaching
摘要：
A new technology for enhancing microwave roasting of gold bearing high arsenic sulphide concentrate with various water contents was proposed. The influence of water content and roasting time on microwave roasting of gold concentrate was investigated, and the mechanism of microwave roasting of gold bearing high arsenic sulphide concentrate with various water contents was analyzed. The results show that the removal rate of sulfur and iodide/iodine leaching rate of gold are mainly dependent on water content. The removal rate of sulfur and the leaching rate of gold reaches 87.95% and 75.08%, respectively, under the conditions of water content of 9% with microwave roasting for 30 min. After the dried concentrate sample and the wetted concentrate sample with 9% water content were roasted in the microwave oven for 60 min, the latter was found by SEM to be more porous than former, its specific surface area was found to increase from 25.6 to 32.7 m(2)/g. (C) 2017 Elsevier B.V. All rights reserved.
作者：
Ye, Yong-jun*;Zhang, Yun-feng;Dai, Xin-tao;Ding, De-xin
期刊：
Journal of Environmental Radioactivity,2017年177:135-141 ISSN：0265-931X
通讯作者：
Ye, Yong-jun
作者机构：
[Ye, Yong-jun; Ding, De-xin] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.;[Dai, Xin-tao; Ye, Yong-jun; Zhang, Yun-feng] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Ye, Yong-jun] U;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.
关键词：
Free radon production rate;Granulated porous media;Permeability;Porosity;Radon diffusion coefficient
摘要：
The particle size and heaped methods of exhalation media have important effects on physical parameters, such as the free radon production rate, porosity, permeability, and radon diffusion coefficient. However, existing methods for determining those parameters are too complex, and time-consuming. In this study, a novel, systematic determining method was proposed based on nuclide decay, radon diffusion migration theory, and the mass conservation law, and an associated experimental device was designed and manufactured. The parameters of uranium ore heap and sandy soil of radon diffusion coefficient (D), free radon production rate (alpha), media permeability (k), and porosity (epsilon) were obtained. At the same time, the practicality of the novel determining method was improved over other methods, with the results showing that accuracy was within the acceptable range of experimental error. This novel method will be of significance for the study of radon migration and exhalation in granulated porous media. (C) 2017 Elsevier Ltd. All rights reserved.
摘要：
The endophyte Pseudomonas sp. XNN8 was separated from Typha orientalis which can secrete indole-3-acetic acid and 1-aminocyclopropane-1-carboxylate deaminase and siderophores and has strong resistance to uranium it was then colonized in the Syngonium podophyllum; and the S. podophyllum-Pseudomonas sp. XNN8 symbiotic purification system (SPPSPS) for uranium-containing wastewater was constructed. Afterwards, the hydroponic experiments to remove uranium from uranium-containing wastewater by the SPPSPS were conducted. After 24 days of treatment, the uranium concentrations of the wastewater samples with uranium concentrations between 0.5 and 5.0 mg/L were lowered to below 0.05 mg/L. Furthermore, the uranium in the plants was assayed using Fourier transform infrared spectroscopy (FTIR) and extended X-ray absorption fine structure (EXAFS) spectroscopy. The Pseudomonas sp. XNN8 was found to generate substantial organic groups in the roots of the Syngonium podophyllum, which could improve the complexing capability of S. podophyllum for uranium. The uranium in the roots of S. podophyllum was found to be the uranyl phosphate (47.4 %) and uranyl acetate (52.6 %).
作者机构：
[Mao JingWen; Sun Jia; Yao FoJun] Chinese Acad Geol Sci, Inst Mineral Resources, MLR Key Lab Metallogeny & Mineral Assessment, Beijing 100037, Peoples R China.;[Duan XianZhe] Univ South China, Sch Nucl Resource Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Sun Jia] C;Chinese Acad Geol Sci, Inst Mineral Resources, MLR Key Lab Metallogeny & Mineral Assessment, Beijing 100037, Peoples R China.
作者机构：
[Xia, Yiqun; Zheng, Weina; Li, Reirei; Xia, Liangshu] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Xia, Yiqun] China Inst Atom Energy, Dept Radiochem, POB 275-26, Beijing 102413, Peoples R China.;[Tans, Kaixuan] Univ South China, Sch Nucl Resource & Nucl Fuel Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Xia, Liangshu] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
摘要：
Basic aspects of uranium adsorption by rice husk have been investigated. The influences of various experimental parameters such as pH, time, adsorbent dosage, rice husk size, temperature and various concentrations of uranium on uptake were evaluated. The thermodynamics and kinetics of adsorption were analyzed by FT-IR and SEM. The adsorption capacity for uranium on rice husk increased upon increasing initial concentration of uranium and temperature, while decreased with the increase of the amount of rice husk. Maximum uranium adsorption was observed at pH = 3 and particle size between 120 μm and 150 μm. Adsorption equilibrium was achieved within 60 min. At 25 °C, the saturated adsorption capacity qmax was up to 15.14 mg/g when the initial concentration of uranium ranged from 10 to 400 mg/dm3. The adsorption of uranium followed Langmuir adsorption isotherm and according to quasi-second order kinetic equation. The calculated values of δHo, δS0, and δGo indicated that the biosorption process was endothermic and spontaneous. Based on FT-IR spectra it may be concluded that hydroxyl, carbonyl, P-O and Si=O groups are the main active sites.
通讯机构：
[Tan, Kaixuan] U;Univ South China, Sch Nucl Resources Engn, Hengyang 421001, Hunan, Peoples R China.
关键词：
diffusion;radon;soil;uranium
摘要：
Radon diffusion and transport through different media is a complex process affected by many factors. In this study, the fractal theories and field covering experiments were used to study the fractal characteristics of particle size distribution (PSD) of six kinds of geotechnical materials (e.g., waste rock, sand, laterite, kaolin, mixture of sand and laterite, and mixture of waste rock and laterite) and their effects on radon diffusion. In addition, the radon diffusion coefficient and diffusion length were calculated. Moreover, new formulas for estimating diffusion coefficient and diffusion length functional of fractal dimension d of PSD were proposed. These results demonstrate the following points: (1) the fractal dimension d of the PSD can be used to characterize the property of soils and rocks in the studies of radon diffusion behavior; (2) the diffusion coefficient and diffusion length decrease with increasing fractal dimension of PSD; and (3) the effectiveness of final covers in reducing radon exhalation of uranium tailings impoundments can be evaluated on the basis of the fractal dimension of PSD of materials.
