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Instability Criterion for Surrounding Rock of Water-Rich Roadway in Sandy-Gravel Stratum Based on Catastrophe Theory

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IOP Conference Series: Earth and Environmental Science 2019年第1期283卷

作者： Yue Yuan Jinlei Fu Jian Qin Xiaokang Wang Bensheng Wang Work Safety Key Lab on Prevention and Control of Gas and Roof Disasters for Southern Coal Mines Xiangtan 411201 China Hunan Provincial Key Laboratory of Safe Mining Techniques of Coal Mines Xiangtan 411201 China School of Resources Environment and Safety Engineering Hunan University of Science and Technology Xiangtan 411201 China

In order to solve the problem of instability discrimination for water-rich roadway in sandy-gravel stratum, taking the displacement function and damaged area function as potential functions of the roadway surrounding rock system based on catastrophe theory, the instability criterions of the roadway in sandy-gravel stratum under seepage were established, i.e. the criterion for extremal modulus of displacement and criterion for the damaged area. Then the specific process for stability discrimination was further proposed. A PFC2D numerical model for a shaft bottom roadway in a large coal mine in Xinjiang was established. The calculation results show that as seepage pressure increases, modulus of displacement and damaged area in surrounding rock present irregular fluctuations and similar change rule. In the latter stage of the increase of seepage pressure, the deformation and damage of the roadway all have experienced a sharp sudden raise. And the conclusion of instability discrimination obtained from the calculation results of catastrophic eigenvalues for modulus of displacement and damaged area are consistent with damage evolution and instability process of the surrounding rock, which verifies the feasibility and applicability of the instability criterions.

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Uranium (VI) bioremediation by Acinetobacter sp. USCB2 isolated from uranium tailings area

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IOP Conference Series: Earth and Environmental Science 2018年第5期170卷

作者： Licheng Li Taotao Zeng Shuibo Xie School of civil engineering University of south china Hengyang China Hunan province key laboratory of pollution control and resources reuse technology University of south china Hengyang China

Bioremediation of uranium (VI)-contaminated aquifers was investigated by using bacteria isolated from a uranium tailing in South China. The bacteria were identified as Acinetobacter on the basis of physiological, biochemical tests and 16S rDNA sequence homology analysis. The protein concentration in the supernatant declined from 50.26 μ g/mL to 40.01 μ g/mL after uranium removal, and the activity of bacterial phosphatase increased from 36.04 U/L to 39.81 U/L. The FTIR, SEM-EDS and XRD demonstrated the involvement of functional groups in U (VI) binding, U accumulated on the surface of the bacteria and the precipitated is Uranyl Sulfite Hydrate. The results from this study demonstrate the potential of the U tolerant, bacterium Acinetobacter sp. USC B2 isolate might be considered as promising candidates in the design of uranium bioremediation strategies.

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Hierarchically Ordered Porous Carbon with Atomically Dispersed FeN4for Ultraefficient Oxygen Reduction Reaction in Proton‐Exchange Membrane Fuel Cells

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Angewandte Chemie 2019年第7期132卷

作者： Mengfei Qiao Ying Wang Quan Wang Guangzhi Hu Xamxikamar Mamat Shusheng Zhang Shuangyin Wang Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental Science School of Chemical Science and Technology Yunnan University Kunming 650504 China Key Laboratory of Chemistry of Plant Resources in Arid Regions State Key Laboratory Basis of Xinjiang Indigenous Medicinal Plants Resource Utilization Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of Science Urumqi 830011 China College of Chemistry and Molecular Engineering Zhengzhou University Zhengzhou 450000 China State Key Laboratory of Chem/Bio-Sensing and Chemometrics Provincial Hunan Key Laboratory for Graphene Materials and Devices College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China

The low catalytic activity and poor mass transport capacity of platinum group metal free (PGM‐free) catalysts seriously restrict the application of proton‐exchange membrane fuel cells (PEMFCs). Catalysts derived from Fe‐doped ZIF‐8 could in theory be as active as Pt/C thanks to the high intrinsic activity of FeN 4 ; however, the micropores fail to meet rapid mass transfer. Herein, an ordered hierarchical porous structure is introduced into Fe‐doped ZIF‐8 single crystals, which were subsequently carbonized to obtain an FeN 4 ‐doped hierarchical ordered porous carbon (FeN 4 /HOPC) skeleton. The optimal catalyst FeN 4 /HOPC‐c‐1000 shows excellent performance with a half‐wave potential of 0.80 V in 0.5 m H 2 SO 4 solution, only 20 mV lower than that of commercial Pt/C (0.82 V). In a real PEMFC, FeN 4 /HOPC‐c‐1000 exhibits significantly enhanced current density and power density relative to FeN 4 /C, which does not have an optimized pore structure, implying an efficient utilization of the active sites and enhanced mass transfer to promote the oxygen reduction reaction (ORR).

关键词： Brennstoffzellen Stofftransfer Mesoporöse Materialien Sauerstoffreduktionsreaktion Zeolith-Analoga

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Biological treatment of wastewater with high concentrations of zinc and sulfate ions from zinc pyrithione synthesis

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Transactions of Nonferrous Metals Society of China 2017年第11期27卷 2481-2491页

作者： Zhi-xiong PENG Hui-jun HE Chun-ping YANG Guang-ming ZENG Shan WEN Zhou YAN Hai-hong XIANG Yan CHENG Sheldon TARRE Michal GREEN College of Environmental Science and Engineering Hunan University Changsha 410082 China Key Laboratory of Environmental Biology and Pollution Control (Hunan University) Ministry of Education Changsha 410082 China Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling College of Environmental Science and Engineering Zhejiang Gongshang University Hangzhou 310018 China Faculty of Civil and Environmental Engineering Israel Institute of Technology Haifa 32000 Israel

An enriched and domesticated bacteria consortium of sulfate-reducing bacteria(SRB)was used to treat wastewater from zinc pyrithione(ZPT)production,and the effects of different reaction parameters on sulfate reduction and zinc precipitation were *** single-factor experimental results showed that the removal rates of Zn2+and24SO?decreased with an increased ZPT concentration ranging from3.0to5.0mg/***2+and24SO?in wastewater were effectively removed under the conditions of30?35°C,pH7?8and an inoculum concentration of10%?25%.The presence of Fe0in the SRB system enhanced Zn2+and24SO?removal and may increase the resistance of SRB to the toxicity of Zn2+and ZPT in wastewater.A Box?Behnken design was used to evaluate the influence of the main operating parameters on the removal rate of24SO?.The optimum parameter values were found to be pH7.45,33.61°C and ZPT concentration of0.62mg/L,and the removal rate of24SO?reached a maximum of91.62%under these optimum conditions.

关键词： biological treatment sulfate reduction sulfate-reducing bacteria wastewater zinc pyrithione zinc

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Study on Occurrence Speciation and Activity of Uranium Tailing Contaminants in the Presence of *** MR-1 under Anaerobic Conditions

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IOP Conference Series: Earth and Environmental Science 2018年第3期170卷

作者： Xichen Zhang Shuibo Xie Hongjuan Liu Yingjiu Liu Hunan Province Key Laboratory of Pollution Control and Resources Reuse Technology University of South China Hengyang China Key Discipline Laboratory for National Defence for Biotechnology in Uranium Mining and Hydrometallurgy University of South China Hengyang China Institute of Nuclear Science and Technology University of South China Hengyang China

Taked a uranium tailings pond in hunan province as the research object, three groups of reaction systems including min (mineral group), min-dbio (mineral-dead bacteria) and min-bio (mineral-viable bacteria) were set up for the sequential batch experiments. The metal elements of U, Fe, Cd, and Pb in the uranium tailings which have reacted with S. oneidensis MR-1 for 2d, 4d, 10d, and 20d were studied by the sequential chemical extraction methods, to analyzed the effect of species of contaminants in Uranium Tailings by S. oneidensis MR-1. The results showed that the residual state is the main occurrence mode of each metal element. The release of contaminants from tailings is mainly attributed to the dissolution of exchangeable state. The complexation or adsorption of the dead bacteria and metal elements leads to the increase of the organic matter. The effect of *** MR-1 promoted the release of each metal elements in the exchangeable state, carbonate binding state, organic matter binding state and the amorphous iron manganese oxide binding state of tailings sample, and the reduction of S. oneidensis MR-1 caused U6+ to produce U4+, resulting in an increase in the content of residuals, while Fe3+ was reduced to Fe2+, resulted in an increase in the binding state of crystalline iron-manganese oxides.

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Effect of coexisting cations on the adsorption of cesium onto poly (β-cyclodextrin)/bentonite composite

Effect of coexisting cations on the adsorption of cesium ont...

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第四届全国核化学与放射化学青年学术研讨会

作者： Hongjuan Liu Shuibo Xie Tiancheng Wang Yingjiu Liu Taotao Zeng Key Discipline Laboratory for National Defence for Biotechnology in Uranium Mining and Hydrometallur Key Discipline Laboratory for National Defence for Biotechnology in Uranium Mining and Hydrometallur Institute of Nuclear Science and Technology University of South China Hengyang 421001 P.R.China Hunan Province Key Laboratory of Pollution Control and Resources Reuse Technology University of So

A novel poly(β-Cyclodextrin)/bentonite composite (β-CD/BNC) was successfully prepared through graft polymerisation by using ammonium persulphate-sodium bisulphate as initiators, and characterized by FT-IR, EDS and *...

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A variable fuzzy set model for assessment of water ecological civilization for a city in china 12

A variable fuzzy set model for assessment of water ecologica...

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Uncertainty Modelling in Knowledge Engineering and Decision Making - 12th International Fuzzy Logic and Intelligent Technologies in Nuclear Science Conference, FLINS 2016

作者： Yuankun, Wang Dong, Sheng Dong, Wang Key Laboratory of Surficial Geochemistry Ministry of Education Department of Hydrosciences School of Earth Sciences and Engineering State Key Laboratory of Pollution Control and Resource Reuse Nanjing University Nanjing210023 China Hunan Water Resources and Hydropower Research Institute Changsha410007 China

ISBN: (纸本)9789813146969

The assessment system for water ecological civilization city is suggested, including a rule layer with 5 factors and an index layer with 19 defined indexes based on the connotation of water ecological civilization. Assessment model is developed based on the variable fuzzy set, which reasonably identifies the relative membership degree and function of simple index and standard interval of each level. Taking Zhuzhou city, China, as an example of comprehensive evaluation of water ecological civilization, the results show that the proposed model can rationally determine ecological civilization grade considering all related indicators. The eco-civilization of water in Zhuzhou city is in a low level: non-harmonious. The results of this paper could provide scientific references for city water management and environment protection. © 2016 by World Scientific Publishing Co. Pte. Ltd.

关键词： Decision making

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Effects of a controlled-release fertilizer on yield, nutrient uptake, and fertilizer usage efficiency in early ripening rapeseed(Brassica napus L.)

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2016年第10期17卷 775-786页

作者： Chang TIAN Xuan ZHOU Qiang LIU Jian-wei PENG Wen-ming WANG Zhen-hua ZHANG Yong YANG Hai-xing SONG Chun-yun GUAN College of Resources and Environment Hunan Agricultural University/Hunan Provincial Key Laboratory of Farmland Pollution Control and Agricultural Resources Use / Hunan Provincial Key Laboratory of Plant Nutrition in Common University/National Engineering Laboratory of College of Resources and EnvironmentSouthern Regional Collaborative Innovation Center for Grain and Oil Crops in China College of Environmental Science and Resources Zhejiang University National Center of Oilseed Crops Improvement Hunan Branch

Background： Nitrogen（N）, phosphorous（P）, and potassium（K） are critical nutrient elements necessary for crop plant growth and development. However, excessive inputs will lead to inefficient usage and cause excessive nutrient losses in the field environment, and also adversely affect the soil, water and air quality, human health, and biodiversity. Methods： Field experiments were conducted to study the effects of controlled-release fertilizer（CRF） on seed yield, plant growth, nutrient uptake, and fertilizer usage efficiency for early ripening rapeseed（Xiangzayou 1613） in the red-yellow soil of southern China during 2011–2013. It was grown using a soluble fertilizer（SF） and the same amounts of CRF, such as SF1/CRF1（3750 kg/hm^2）, SF2/CRF2（3000 kg/hm^2）, SF3/CRF3（2250 kg/hm^2）, SF4/CRF4（1500 kg/hm^2）, SF5/CRF5（750 kg/hm^2）, and also using no fertilizer（CK）. Results： CRF gave higher seed yields than SF in both seasons by 14.51%. CRF4 and SF3 in each group achieved maximum seed yield（2066.97 and 1844.50 kg/hm^2, respectively）, followed by CRF3（1929.97 kg/hm^2） and SF4（1839.40 kg/hm^2）. There were no significant differences in seed yield among CK, SF1, and CRF1（P0.05）. CRF4 had the highest profit（7126.4 CNY/hm2） and showed an increase of 12.37% in seed yield, and it decreased by 11.01% in unit fertilizer rate compared with SF4. The branch number, pod number, and dry matter weight compared with SF increased significantly under the fertilization of CRF（P0.05）. The pod number per plant was the major contributor to seed yield. On the other hand, the N, P, and K uptakes increased at first and then decreased with increasing the fertilizer rate at maturity, and the N, P, and K usage efficiency decreased with increasing the fertilizer rate. The N, P, and K uptakes and usage efficiencies of the CRF were significantly higher than those of SF（P0.05）. The N accumulation and N usage efficiency of CRF increased by an average of 13.66% and 9.74 percentage points, respectively, compared to

关键词： Early ripening rapeseed controlled-release fertilizer Yield Nutrient uptake Fertilizer usage efficiency

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The adsorption effect of three minerals on chemical oxygen demand, total nitrogen, total phosphorus and heavy metals in biogas slurry

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IOP Conference Series: Earth and Environmental Science 2018年第4期199卷

作者： M Cai F C Li S H Chen L Gao L Guo School of Environment and Resources of Southwest University of Science and Technology Mianyang 621010 China Sichuan Key Laboratory of Soil Environmental Pollution Control and Remediation Chengdu 610014 China. Chengdu Haoyu Siyuan Environmental Technology Co. Ltd. Chengdu 610000 China Rural Energy Office of Sichuan Provincial Chengdu 610041 China

Contraposing the intractable problem of high content of nitrogen, phosphorus and heavy metals in biogas slurry from livestock and poultry farm, the adsorption effect of three minerals (montmorillonite, kaolin and acticarbon) on chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP) and heavy metals (Zn, Cu, Cr and As) have been studied. In addition, the mineral material with good adsorption effect has been screened. Based on the screened mineral material, the adsorption effects of screened mineral material dosage and the initial pH value of biogas slurry on COD, TN, TP and heavy metals have been analysed. The results show that the adsorption effect of montmorillonite (MMT) is obvious, followed by kaolin and acticarbon. Concretely, the removal rates of TP, Zn, Cu, Cr are up to 63.0%, 72.1%, 67.4%, 58.5% respectively adsorbed by MMT; What is more, the removal rate increased by the increase of MMT dosage. Nevertheless, the adsorption of COD and TN gradually reaches equilibrium when the dosage of MMT is 3%. Likewise, the removal rate of TP, Zn, Cu and Cr increase slowly. In comparison, As has a highest removal rate, up to 58.5%. The adsorption of COD, TN, TP and heavy metals has little effect with the increase of pH adsorbed by MMT, while the removal rate of TP sharply increases with the increase of pH, from 29.1% to 77.8%. Specially, the removal rates of TP range from 71.6% to 77.8% when pH is between 8.0 and 9.5. All of the results indicate that MMT is the optimal adsorption material, and the optimum MMT dosage is 3%, the appropriately initial pH of biogas slurry is alkaline.

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Responses of Carbonic Anhydrase to Cadmium in the Zinc/Cadmium Hyperaccumulator Picris divaricata Vant.

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Pedosphere 2016年第5期26卷 709-716页

作者： LIU Saihua TANG Yetao QIU Rongliang YING Rongrong GE Ruiguang JI Xionghui School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510275(China) Hunan Soil and Fertilizer Institute Changsha 310125(China) Guangdong Provincial Key Lab of Environmental Pollution Control and Remediation Technology Guangzhou 510275(China) Nanjing Institute of Environmental Sciences Ministry of Environmental ProtectionNanjing 210042(China) Key Laboratory of Gene Engineering of the Ministry of Education and State Key Laboratory of Biocontrol College of Life ScienceSun Yat-sen UniversityGuangzhou 510275(China)

A number of higher plants are able to hyperaccumulate cadmium(Cd). However, it is unknown whether cadmium(Cd) plays a biological functional role in the carbonic anhydrase(CA) of hyperaccumulators. A hydroponic experiment was conducted to explore the potentially physiological function of Cd in CA and the accumulation and tolerance of Cd in the Zn/Cd hyperaccumulator Picris divaricata Vant. P. divaricata was exposed to nutrient solutions with six Cd concentrations(0, 5, 10, 25, 50 and 75 μmol L^(-1)). After 12 d, plants were harvested for the analysis of plant biomass, Cd concentration and CA activity. The Cd concentrations in plant increased with the increasing Cd in nutrient solution, reaching 640 and 3 100 mg kg^(-1) in shoot and root, respectively, at the 75 μmol L^(-1) Cd treatment. Meanwhile, plant growth was enhanced by the Cd treatments at 5–25 μmol L^(-1), but it was significantly inhibited when the plants were exposed to solutions with higher Cd concerntrations(50 and 75 μmol L^(-1)). Exposure to Cd significantly increased the CA activity in P. divaricata, which reached a maximum value of 21.27 U mg^(-1) proteins at the 25 μmol L^(-1)Cd treatment, and the CA activity and shoot Cd concentration were positively correlated at solutions Cd of ≤ 25 μmol L^(-1). Moreover, two protein bands appeared on the denatured gel electrophoresis of purified CA, indicating that P. divaricata may have CA isomers with their respective molecular weights at around 60 and 55 k Da, at least one of which is Cd-bound. In addition, trace amounts of Cd in purified CA significantly increased with the supplied Cd concentration in nutrient solution(5–25 μmol L^(-1)). The results suggested that Cd may play a biological role by enhancing the activities and forming the active Cd-specific CA in the hyperaccumulator P. divaricata.

关键词： Cd enzyme purification heavy metal metal-contaminated soil phytoremediation plant enzyme protein purification

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