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Crack evolution of soft–hard co.posite layered rock-like specimens with two fissures under uniaxial co.pression

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Frontiers of Structural and Civil Engineering 2021年第6期15卷 1372-1389页

作者： Dong ZHOU Yicheng YE Nanyan HU Weiqi WANG Xianhua WANG School of Resources and environmental Engineering Wuhan University of Science and TechnologyWuhan 430081China Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources Wuhan 430081China sinosteel wuhan safety and environmental protection research institute co. Ltd.Wuhan 430081China

Aco.stic emission and digital image co.relation were used to study the spatiotemporal evolution characteristics of crack extension of soft and hard co.posite laminated rock masses(SHCLRM)co.taining double fissures under uniaxial *** effects of different rock co.bination methods and prefabricated fissures with different orientations on mechanical properties and crack co.lescence patterns were *** characteristics of the aco.stic emission source location distribution,and frequency changes of the crack evolution process were also *** test results show that the damage mode of SHCLRM is related to the co.bination mode of rock layers and the orientation of *** layers predominantly produce tensile cracks;soft layers produce shear *** first crack always sprouts at the tip or middle of prefabricated fractures in hard *** aco.stic emission signal of SHCLRM with double fractures has clear stage characteristics,and the state of crack development can be inferred from this signal to provide early warning for rock fracture *** study can provide a reference for the assessment of the fracture development status between adjacent roadways in SHCLRM in underground mines,as well as in roadway layout and support.

关键词： soft−hard co.posite layered rock mass double cracks crack evolution aco.stic emission digital image co.relation

Effects of shear force on formation and properties of anoxic granular sludge in SBR

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Frontiers of environmental Science & Engineering 2013年第6期7卷 896-905页

作者： Xinyan ZHANG Binbin WANG Qingqing HAN Hongmei ZHAO Dangco.g PENG School of environmental and Municipal Engineering Xi'an University of Architecture and Technology Xi'an 710055 China sinosteel wuhan safety & environmental protection research institute Wuhan 430081 China School of environmental Science and Engineering Chang'an University Xi'an 710056 China

This paper reports the effects of shear force on anoxic granular sludge in sequencing batch reactors （SBR）. The study was carried out in two SBRs （SBR1 and SBR2） in which sodium acetate （200mg co.·L^-1） was used as the sole substrate and sodium nitrate （40 mgNO3-N·L^-1） was employed as the electron acceptor. The preliminary objective of this study was to cultivate anoxic granules in the SBR in order to investigate the effects of shear force on the formation of anoxic granular sludge and to co.pare the properties of anoxic sludge in the SBR. This study reports new results for the values of average velocity gradient, a measure of the applied shear force, which was varied in the two SBRs （3.79 s^-1 and 9.76 s^-1 for SBR1 and SBR2 respectively）. The important findings of this research highlight the dual effects of shear force on anoxic granules. A low shear force can produce large anoxic granules with high activity and poor settling ability, whereas higher shear forces produce smaller granules with better settling ability and lower activity. The results of this study show that the anoxic granulation is closely related to the strength of the shear force. For high shear force, this research demonstrated that： 1） granules with smaller diameters, high density and good settling ability were formed in the reactor, and 2） granular sludge formed faster than it did in the low shear force reactor （41days versus 76 days）. Once a steady-state has been achieved, the nitrate and co. removal rates were found to be 98% and 80%, respectively. For low shear force, such as was applied in SBR1, this research demonstrated that： 1） the activity of anoxic granular sludge in low shear force was higher than that in high shear force, 2） higher amount of soluble microbial products （SMPs） were produced, and 3） large pores were observed inside the larger granules,which are beneficial for nitrogen gas diffusion. Electron microsco.ic examination of the anoxic granules in both reactors showed that the

关键词： denitrification anoxic granular sludge,sequencing batch reactors (SBR) shear force

safety study on HIC co.taining waste resin with respect to hydrogen release

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Nuclear Science and Techniques 2019年第4期30卷 35-43页

作者： Shuai-Wei Zhao Mei-Lan Jia Xing-Qian Jiao Meng-Qi Qiu Hong-Hui Li Yu-Chen Liu Liang Mao Wei Liu Dong Liang China institute for Radiation protection Sichuan environmental protection and Engineering co. LTD. CNNC

To explore the behavior of radiolytically produced hydrogen release from the waste resin stored in a high integrated co.tainer(HIC), and the mechanism of hydrogen diffusion in a near-surface disposal facility, both experimental studies and numerical simulations were performed through an accelerated irradiation test and simulated disposal, respectively. Results indicated that,100 years after disposal, the highest hydrogen co.centration appeared in the cell where the HICs were placed. The volume fraction for different scenarios postulated in the numerical simulation was 2.64% for Scenario 1, 2.28% for Scenario 2, and 3.965% for Scenario 3, all of which are lower than the hydrogen explosion limit of 4.1%. The results indicated that the simulated HIC disposal scheme is safe.

关键词： Radioactive waste resin High integrated co.tainer Repository Radiolysis Hydrogen release

research on Identification and Evaluation Technology and Management and co.trol System of Enterprise Major Risk Based on Preventing Serious Accidents

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Research on Identification and Evaluation Technology and Man...

Mechanical behavior and damage co.stitutive model of sandstone under hydro-mechanical (H-M) co.pling

作者： Wang Xianhua Xia Shuiguo Wang Biao sinosteel wuhan safety and environmental protection research institute

Some serious accidents happened in China in recent years show that,the management idea of taking the industry as the key to prevent serious accidents can not adapt to the current practice of safe production and how to set up a precise,forward-looking,systematic and co.prehensive prevention and co.trol system for preventing serious accidents has been a major task facing *** curb serious accidents,we must move forward the threshold,pre-co.trol risks,close loop management and make co.tinuous improvements and co.trol risks before hidden dangers emerged and nip serious accidents in the *** systems are in motion,and the motion of the system is the result of co.tradictions and struggles in the *** is a universal principle in the universe,and the safety system obeys *** the safety system is co.plex in structure,it can be summarized as the result of the interaction between "risk" and "risk prevention and co.trol".In this paper,curbing serious accidents and prevent major production safety risks as the goal,the system theory,cybernetics and information theory and risk management theory are used in production safety risk co.trol,the accident risk point and risk unit are taken as objects,and the accident risk points higher risks(5 high-risks) identification as the foundation,to build a "1" + "5" index system of risk monitoring and co.trol,set up serious risk assessment model,determine the serious risk determination threshold and grading standards,provide technical guidance for enterprises and governments to implement production safety risk co.trol at different levels,and also provide technical support for the development of local production safety risk monitoring and warning *** realistic risk indicators"1"Unit real risk indicators are co.posed of risk severity aggregation indicators of risk points in the unit and risk co.trol indicators of the *** severity aggregation indicators of risk points in the unit represent the severity of risk occu

关键词： safety production risk accident risk point risk assessment model significant risk determination threshold

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International Journal of Mining Science and Technology 2024年第6期34卷 837-853页

作者： Tao Tan Chunyang Zhang Yanlin Zhao Xiaoshuang Li School of Resources and environmental Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of safety and Health in Metal Mines Maanshan 243000China sinosteel Maanshan General institute of Mining research co. Ltd.Maanshan 243000China School of Resource&Environment and safety Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Urban co.struction Changzhou UniversityChangzhouJiangsu 213164China

Underground engineering often passes through water-rich fractured rock masses, which are prone to fracture and instability under the long-term co.pling of in-situ stress field and pore water(P-W) pressure, ultimately threatening the stability of underground structures. In order to explore the mechanical properties of rocks under H-M co.pling, the co.responding damage co.stitutive(D-C) model has beco.e the focus of attention. co.sidering the inadequacy of the current research on rock strength parameters,energy evolution characteristics and D-C model under H-M co.pling, the mechanical properties of typical sandstone samples are discussed based on laboratory tests. The results show that the variation of characteristic stresses of sandstone under H-M co.pling co.forms to the normalized attenuation equation and Mohr-co.lomb(M-C) criterion. The P-W pressure mechanism of sandstone exhibits a dynamic change from softening effect to H-M fracturing effect. The closure stress is mainly provided by co.esive strength, while the initiation stress, damage stress, and peak stress are jointly dominated by co.esive strength and friction strength. In addition, residual stress is attributed to the friction strength formed by the bite of the fracture surface. Subsequently, the energy evolution characteristics of sandstone under H-M co.pling were studied, and it was found that P-W pressure weakened the energy storage capacity and energy dissipation capacity of sandstone, and H-M fracturing was an important factor in reducing its energy storage efficiency. Finally, co.bined with energy dissipation theory and statistical damage theory, two types of D-C models co.sidering P-W pressure are proposed acco.dingly, and the model parameters can be determined by four methods. The application results indicate that the proposed and modified D-C models have high reliability, and can characterize the mechanical behavior of sandstone under H-M co.pling, overco.e the inco.venience of existing D-C models

关键词： H-M co.pling Water-saturated sandstone Mechanical mechanism Energy evolution D-C model

N_2O deco.position over K/Na-promoted Mg/Zn–Ce–co.alt mixed oxides catalysts

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Journal of environmental Sciences 2014年第7期26卷 1437-1443页

作者： Jinli Zhang Hui Hu Jie Xu Gaoming Wu Zhaowei Zeng School of environmental Science and Engineering Huazhong University of Science and Technology Shanghai LongKing environmental protection co. Ltd. wuhan Iron and Steel (Group) co.p.

Three groups of co.alt mixed oxide catalysts（Mg/Zn-co. Mg/Zn-Ce-C, K/Na-Mg/Zn-Ce-co.were prepared by sol-gel or impregnation methods. The synergistic effects of transition metal, rare earth metal and alkali metal on co.alt mixed catalysts for nitrous oxide（N2O）deco.posing to N2 and O2were investigated. The experimental results revealed that the catalytic activity for N2 O deco.position was promoted as co.＋was replaced partially by Zn2＋/Mg2＋, moreover, the characterization analysis by XRD and XPS showed that Zn2＋/Mg2＋replaced co.＋successfully into the spinel structure of co.O4 and promoted significantly the catalytic activity. Especially, the addition of CeO2 and K2O/Na2O decreased the binding energy and resulted in an increase in the density of the electron cloud around co.and an improvement of the catalytic activity. Of the investigated co.alt mixed catalysts, the best catalytic activity was shown by 2% K-Zn0.5-Ce0.05-co.catalyst.

关键词： N2O Catalytic deco.position CeO2 Alkali metal

Multi-process and multi-pollutant co.trol technology for ultra-low emissions in the iron and steel industry

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Journal of environmental Sciences 2023年第1期123卷 83-95页

作者： Tingyu Zhu Xindong Wang Yong Yu Chao Li Qun Yao Yuran Li institute of Process Engineering Chinese Academy of SciencesBeijing 100190China HBIS Group co. Ltd.Shijiazhuang 050023China ACRE co.ing&Refractory Engineering co.sulting co.poration MCCDalian 116085China sinosteel Tiancheng environmental protection Science&Technology co.Ltd. Wuhan 430205China

The iron and steel industry is not only an important foundation of the national eco.omy,but also the largest source of industrial air *** to the current status of emissions in the iron and steel industry,ultra-low pollutant emission co.trol technology has been researched and ***-phase proportion co.trol technology has been developed for magnesian fluxed pellets,and a blast furnace smelting demonstration project has been established to use a high proportion of fluxed pellets(80%)for the first time in China to realize source emission reduction of SO_(2)and NO_(x).Based on the characteristics of high NO_(x)co.centrations and the co.xistence of multiple pollutants in co.e oven flue gas,low-NO_(x)co.bustion co.pled with multi-pollutant co.perative co.trol technology with activated carbon was developed to achieve efficient removal of multiple pollutants and resource utilization of *** on the characteristics of co.existing multiple pollutants in pellet flue gas,selective non-catalytic reduction(SNCR)co.pled with ozone oxidation and spray drying adsorption(SDA)was developed,which significantly reduces the operating co.t of the *** the light of the high humidity and high alkalinity in flue gas,filter materials with high humidity resistance and co.rosion resistance were manufactured,and an integrated pre-charged bag dust co.lector device was developed,which realized ultralow emission of fine particles and reduced filtration resistance and energy co.sumption in the *** source emission reduction,process co.trol and end-treatment technologies,five demonstration projects were built,providing a full set of technical solutions for ultra-low emissions of dust,SO_(2),NO_(x),SO_(3),mercury and other pollutants,and offering technical support for the green development of the iron and steel industry.

关键词： Iron and steel industry air pollution whole-process co.trol ultra-low emission

Gold Nanoparticles of Multiple Shapes Synthesized in L-Tryptophan Aqueous Solution

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Transactions of Tianjin University 2018年第5期24卷 401-414页

作者： Jinsheng Sun Guangxin Liu Sheng Fu Fang Cai Hong Yin Hao Lv Jie He School of Chemical Engineering and Technology Tianjin University wuhan Guolitong Energy environmental protection co. Ltd

In this paper, we describe a simple and efficient synthesis of gold nanoparticles(GNPs) of various shapes(spherical, rod-like, hexagonal, truncated triangular, and triangular) using Au(Ⅲ) reduction in aqueous solutions by L-tryptophan. We evaluated the influences of reaction temperature, foreign metal ions Ag(Ⅰ), and surfactants of nonionic(polyethylene glyco., PEG), anionic(sodium dodecyl sulfate, SDS), and cationic(cetyltrimethyl ammonium bromide, CTAB) on GNPs synthesis. We characterized the resultant GNPs using UV–visible adsorption spectrosco.y, transmission electron microsco.y/high-resolution transmission electron microsco.y, scanning electron microsco.y, X-ray diffraction, X-ray photoelectron spectrosco.y, selected-area electron diffraction, and Fourier-transform infrared spectrosco.y. We fabricated the variously sized GNPs by co.trolling the rate of the reduction of gold ions in aqueous solution by varying the reaction temperature: the higher the temperature, the smaller the gold nanospheres. We found the existence of Ag(Ⅰ) to reinforce the reduction of Au(Ⅲ) and to co.respond with the appearance of some amorphous bimetallic Au/Ag nanoparticles. Additionally, we found the presence of surfactants to greatly influence the shape of the formed GNPs, especially the presence of CTAB, which results in the anisotropic growth of gold nanocrystals into hexagonal, truncated triangular, and triangular nanoplates. In addition, with the increase in CTAB co.centration, we found the amount of gold nanoplates to first increase and then decrease. Finally, we performed preliminary explorations of the reduction process and morphological evolution to propose possible co.responding reduction and morphological evolution pathways.

关键词： Gold nanoparticles L-Tryptophan Surfactants Anisotropic growth Morphology

Assessment, co.position and Possible Source of Organochlorine Pesticides in Surface Soils from rmqi, China

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Pedosphere 2015年第6期25卷 888-900页

作者： CHEN Min CHEN Li HUANG Ping School of environmental Science and Engineering of Sun Yat-Sen University Cnhomeland and environmental co. Ltd. institute of Plant protection and environmental protection Beijing Academy of Agricultural and Forestry Science

Twenty-eight surface soil samples from 5 functional zones （park, traffic roadside, business/residential area, rural area, and industrial area） of Uruimqi, China were co.lected and analyzed for the co.centrations of 14 organochlorine pesticides （OCPs）, such as 3 isomers of hexachlorocyclohexane （HCHs）（α-HCH, β-HCH, and γ-HCH）, 4 dichlorodiphenyltrichloroethanes （DDTs）（p,p′-DDT and its metabolites p, p′-DDD （1,1-dichloro-2,2-bis（p-chlorophenyl）ethane） and p,p′-DDE （1,1-dichloro-2,2-bis（4-chorophenyl）ethylene）, and o, p′-DDT）, and methoxychlor, aiming to survey the residue levels and co.positions of these 14 OCPs, to identify possible sources of the OCPs, and to assess their potential risks to human health and the environment in surface soils of Ur/imqi. The co.centrations ranged from non-detected to 30.86μg kg^-1 for HCHs （sum of α-, β-, and γ-HCH）, from non-detected to 40.03 μg kg^-1 for DDTs （sum of p, p′-DDT, p, p′-DDD, p, p′-DDE, and o, p′-DDT）, and from non-detected to 11.95 μg kg^-1 for methoxychlor. The total co.centrations of the OCPs ranged from 16.40 to 84.86 μg kg^-1, with a mean of 41.89 ± 16.25 μg kg^-1. Acco.ding to the measured co.centrations and occurrence rates of the 14 OCPs, DDTs, HCHs, and methoxychlor were the most dominant co.pounds. Among the 5 functional zones, the total co.centration of OCPs was in the order of rural area 〉 traffic roadside 〉 park 〉 business/residential area 〉 industrial area. The different co.positions of DDTs and HCHs indicated that the residues of these co.pounds in most soil samples originated from historical application, besides slight recent introduction at some sampling sites. The results of Pearson co.relation analysis showed that soil total organic carbon played an important role in the residue levels of HCHs, but such relationships were not found with DDTs or other OCPs. The soil quality of Uriimqi was classified as Class I based on the guidelines of the Chinese environmental Quality Standard for Soil （GB15618-199

关键词： dichlorodiphenyltrichloroethane (DDT) factor analysis hexachlorocyclohexane (HCH) methoxychlor residue level risk soil quality