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Arbuscular mycorrhizal fungi ameliorate the chemical properties and enzyme activities of rhizosphere soil in reclaimed mining subsidence in northwestern china

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Journal of Arid Land 2019年第1期11卷 135-147页

作者： QIU Lang BI Yinli JIANG Bin WANG Zhigang ZHANG Yanxu Yryszhan ZHAKYPBEK State Key Laboratory of Coal Resources and Safe mining China University of Mining and Technology (Beijing) College of Geoscience and Surveying Engineering China University of Mining and Technology (Beijing) Satbayev university

In semi-arid region of northwestern china, underground mining subsidence often results in decreased vegetation coverage, impoverishment of soil fertility and water stress. In addition, the physical-chemical and biological properties of soil also change, resulting in more susceptible to degradation. In particular, subsidence causes disturbance of the symbioses of plant and microbe that can play a beneficial role in the establishment of vegetation communities in degraded ecosystems. The objective of this study was to evaluate the effects of revegetation with exotic arbuscular mycorrhizal fungi(AMF) inoculum on the chemical and biological properties of soil over time in mining subsidence areas. Soils were sampled at a depth up to 30 cm in the adjacent rhizosphere of Amorpha fruticose Linn. from five reclaimed vegetation communities in northwestern china. In August 2015, a field trial was set up with five historical revegetation experiments established in 2008(7-year), 2011(4-year), 2012(3-year), 2013(2-year) and 2014(1-year), respectively. Each reclamation experiment included two treatments, i.e., revegetation with exotic AMF inoculum(AMF) and non-AMF inoculum(the control). Root mycorrhizal colonization, glomalin-related soil protein(GRSP), soil organic carbon(SOC), soil nutrients, and enzyme activities were also assessed. The results showed that mycorrhizal colonization of inoculated plants increased by 33.3%–163.0% compared to that of non-inoculated plants(P<0.05). Revegetation with exotic AMF inoculum also significantly improved total GRSR(T-GRSP) and easily extracted GRSP(EE-GRSP) concentrations compared to control, besides the T-GRSP in 1-year experiment and the EE-GRSP in 2-year experiment. A significant increase in SOC content was only observed in 7-year AMF reclaimed soils compared to non-AMF reclaimed soils. Soil total N(TN), Olsen phosphorus(P) and available potassium(K) were significantly higher in inoculated soil after 1–7 years of reclamation(except for in

关键词： revegetation mycorrhizal colonization glomalin-related soil proteins arbuscular mycorrhizal fungi coal mining Amorpha fruticose

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Hemolysis of PM_(10) on RBCs in vitro:An indoor air study in a coal-burning lung cancer epidemic area

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Geoscience Frontiers 2022年第1期13卷 506-511页

作者： Mengyuan Zhang Longyi Shao Tim Jones Ying Hu Rachel Adams Kelly BéruBé State Key Laboratory of Coal Resources and Safe mining and College of Geoscience and Surveying EngineeringChina University of Mining&TechnologyBeijing 100083China School of Earth and Environmental Sciences Cardiff UniversityMuseum AvenueCardiff CF103YEUK Guangdong Province Nuclear Industry Geological Bureau Guangzhou 510800China School of Health Sciences Cardiff Metropolitan UniversityLlandaff CampusWestern AvenueCardiff CF52YBWalesUK School of Biosciences Cardiff UniversityMuseum AvenueCardiff CF103AXWalesUK

Epidemiological studies have suggested that inhalation exposure to indoor ambient air from coal-burning environments is causally associated with respiratory health *** order to explore the toxicological mechanisms behind the adverse health effects,the hemolytic activity of PM_(10)(particulate matter with an aerodynamic diameter of 10 um or less)samples collected from homes burning coal in the recognized china"cancer village"Xuanwei were evaluated and matched against their trace elemental *** results demonstrated that the hemolytic activity of indoor PM_(10) in coal-burning environments ranged from 4.28%to 5.24%,with a clear positive dose-response *** low dose samples exhibited a reduced hemolytic activity,PM_(10) could have a toxic effect upon people in a coal-burning indoor environment for extended time *** concentrations of analyzed trace elements in PM_(10) samples ranged from 6966 to 12,958 *** the analyzed elements,Zn,Ti,Ni,Cu,Pb,Ba,Mn,Cr and V were found at higher concentrations and accounted for over 95%of the total *** concentrations of total analyzed elements in the PM_(10) samples revealed a significant positive correlation with PM_(10) hemolytic *** the analyzed elements,Zn,Pb and Cs positively correlated with hemolysis,while Li,U and V negatively correlated with the hemolysis of human red blood cells(RBCs).Therefore,the heavy metal elements could be one of the main factors responsible for the hemolytic capacity of indoor PM_(10) in coal-burning environments.

关键词： Air pollution PM_(10) Coal Hemolysis Xuanwei County

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Floor heave mechanism for gob-side entry retaining with concrete blocks and control method:A case study

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Underground Space 2024年第2期15卷 244-259页

作者： Jiong Wang Peng Liu Manchao He Guangyuan Yu Huanzhi Tian State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China College of mining Engineering North China University of Science and TechnologyTangshan 063210China

The issue of significant floor heave deformation in gob-side entry retaining has long been a challenging problem in the context of longwall *** paper studies the floor heave failure mechanism and control method for gob-side entry retaining with concrete blocks in Guizhou Faer Coal Mine in *** on Rankine’s earth pressure theory,the effective shear stress equation for the plastic slip of roadway floor is *** deformation mechanism of floor heave in a retaining roadway with a block wall is revealed in this *** new comprehensive control method is proposed,encompassing roof pre-splitting blasting for pressure relief,reinforcing cables for roof control,double directions control bolts for concrete block,and pliability cushion yielding ***3D numerical calculation model is established,which shows that the new method can effectively reduce the average vertical stress peak value of the entity coal floor by 34.6%and significantly reduce the pressure source causing the roadway floor ***,a multi-parameter real-time online monitoring system for mine pressure was designed,and field tests were carried *** results show that the maximum value of roadway floor heave under the new method is 163 mm,reduced by 66.9%,and the roadway floor heave is effectively *** research findings offer a fresh perspective and new ideas for controlling floor heave in mining operations.

关键词： Gob-side entry retaining Floor heave mechanism Plastic slip Control methods Mine pressure monitoring

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A Relationship Between the Conditional g-Evaluation System and the Generator g and Its Applications

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Acta Mathematica Sinica,English Series 2007年第8期23卷 1427-1434页

作者： Sheng Jun FAN College of Sciences China University of Mining and Technology Xuzhou 221008 P. R. China

In this paper, under the most elementary conditions on a backward stochastic differential equation （BSDE for short） introduced by Peng, a new relationship between the conditional g-evaluation system and the generator g of BSDE is obtained in the sense of ＂process＂, based on some recent results of Jiang. Moreover, as applications, two converse comparison theorems and two uniqueness theorems on the generators of BSDEs are proved.

关键词： backward stochastic differential equation g-evaluation g-expectation generator converse comparison theorem

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Phonon Thermal Transport at Interfaces of a Graphene/Vertically Aligned Carbon Nanotubes/Hexagonal Boron Nitride Sandwiched Heterostructure

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Chinese Physics Letters 2024年第1期41卷 57-62页

作者：李檬璘 Muhammad Asif Shakoori 王瑞鹏李海鹏 School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221116China

Molecular dynamics simulation is used to calculate the interfacial thermal resistance of a graphene/carbon nanotubes/hexagonal boron nitride(Gr/CNTs/hBN)sandwiched heterostructure,in which vertically aligned carbon nanotube(VACNT)arrays are covalently bonded to graphene and hexagonal boron nitride *** find that the interfacial thermal resistance(ITR)of the Gr/VACNT/hBN sandwiched heterostructure is one to two orders of magnitude smaller than the ITR of a Gr/hBN van der Waals heterostructure with the same plane *** is observed that covalent bonding effectively enhances the phonon coupling between Gr and hBN layers,resulting in an increase in the overlap factor of phonon density of states between Gr and hBN,thus reducing the ITR of Gr and *** addition,the chirality,size(diameter and length),and packing density of sandwich-layer VACNTs have an important influence on the ITR of the *** the same CNT diameter and length,the ITR of the sandwiched heterostructure with armchair-shaped VACNTs is higher than that of the sandwiched heterostructure with zigzag-shaped VACNTs due to the different chemical bonding of chiral CNTs with Gr and *** the armchair-shaped CNT diameter increases or the length decreases,the ITR of the sandwiched heterostructure tends to ***,the increase in the VACNT packing density also leads to a continuous decrease in the ITR of the sandwiched heterostructure,attributed to the extremely high intrinsic thermal conductivity of CNTs and the increase of out-of-plane heat transfer *** work may be helpful for understanding the mechanism for ITR in multilayer vertical heterostructures,and provides theoretical guidance for a new strategy to regulate the interlayer thermal resistance of heterostructures by optimizing the design of sandwich layer thermal interface materials.

关键词： sandwich shaped packing

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Propagation of Ion-Acoustic Wave in an Inhomogeneous Dusty Plasma with. Dust Charge Fluctuation

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Chinese Physics Letters 2007年第1期24卷 151-154页

作者：李经菊肖德龙李阳芳马锦秀 Department of Physics Science and technology China University of Mining and Technology Xuzhou 220018 Department of Modern Physics University of Science and Technology of China Hefei 230026

The propagation of dust ion-acoustic wave in an inhomogeneous dusty plasma is studied by taking the dust charge fluctuation and collisions into account. It is shown that the dust charge fluctuation brings a phase shift to the wave. Furthermore, because of the presence of dust charge fluctuation, a new damping term rises, which makes the damping more sharply.

关键词： ION acoustic waves COLLISIONS (Physics) SCATTERING (Physics) WAVES (Physics)

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Simulation study of integrated‐gate‐commutated‐thyristor based superconducting hybrid direct current circuit breaker

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High Voltage 2023年第6期8卷 1275-1284页

作者： Muhammad Junaid Wenqing Yu Shuzhi Cao Xiaolong Yu Dongsheng Yu Weilin Zong Jianhua Wang School of Electrical Engineering China University of Mining and TechnologyXuzhouChina State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina

With the development of a distributed generation,direct current(DC)load and energy‐storage equipment,voltage‐source‐converter‐based medium‐voltage DC systems(VSC‐MVDC)have attracted more attention due to its low power consumption,high reliability,independent power control and so ***,VSC‐MVDC has the problem of DC fault isolation,which requires the fast‐acting DC circuit‐breakers to isolate faulty lines and ensure low *** problem can be solved by coordinating resistive type superconducting‐fault‐current‐limiter(R‐SFCL)and integrated‐gate‐commutated‐thyristor(IGCT)based hybrid circuit *** on this,IGCT based superconducting DC circuit breaker(SDCCB)is proposed and *** R‐SFCL with IGCT could realise large current limiting and interruption and ensure low *** addition,the IGCT based hybrid DC circuit breaker(IGCT‐HDCCB)is compared with the traditional insulated gate bipolar transistor(IGBT)based hybrid DC circuit breaker(IGBT‐HDCCB)to evaluate which circuit breaker is more suitable for VSC‐*** results show that,coordination based on R‐SFCL and SDCCB,the fault current is successfully limited from 17.6 to 2.1 kA,and then inter-rupted within 3.8 *** addition,IGCT‐HDCCB overcomes the disadvantage that IGCT has less interrupting capacity than IGBT,retains the advantage of low cost of IGCT and is more suitable for MVDC system.

关键词： bipolar fault overcome

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Comparison of large deformation failure control method in a deep gob-side roadway: A theoretical analysis and field investigation

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Journal of Mountain Science 2023年第10期20卷 3084-3100页

作者： WANG Jiong LIU Peng HE Man-chao LIU Yi-peng DU Chang-xin State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China

Under the dual influence of the mining disturbance of the previous working face and the advanced mining of the working face,the roadway is prone to large deformation,failure,and *** stabilization has always significantly influenced deep mining *** this article we used the research background of the large deformation failure roadway of Fa-er Coal Mine in Guizhou Province of china to propose two control methods:bolt-cable-mesh+concrete blocks+directional energy-gathering blasting(BCM-CBDE method)and 1st Generation-Negative Poisson’s Ratio(1G NPR)cable+directional energy-gathering blasting+dynamic pressure stage support(πgirder+single hydraulic prop+retractable U steel)(NPR-DEDP method).Meantime,we compared the validity of the large deformation failure control method in a deep gob-side roadway based on theoretical analysis,numerical simulations,and field *** results show that directional energy-gathering blasting can weaken the pressure acting on the concrete ***,the vertical stress of the surrounding rock of the roadway is still concentrated in the entity coal side and the concrete blocks,showing a’bimodal’***-CBDE method cannot effectively control the stability of the ***-DEDP method removed the concrete *** shows using the 1G NPR cable with periodic slipping-sticking characteristics can adapt to repeated mining *** peak value of the vertical stress of the roadway is reduced and transferred to the deep part of the surrounding rock mass,which promotes the collapse of the gangue in the goaf and fills the *** pressure of the roadway roof is reduced,and the gob-side roadway is fundamentally ***,the dynamic pressure stage support method withπgirder+single hydraulic prop+retractable U steel as the core effectively protects the roadway from dynamic pressure impact when the main roof is periodically *** the on-site implementation of NPR-DEDP method,the deformation

关键词： Deep gob-side roadway Deformation failure control Roof structure mechanical model Stress field distribution mining safety .Failure mode.

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Simulation Study and Probe on UWB Wireless Communication in Underground Coal Mine

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Journal of china university of mining and technology 2006年第3期16卷 296-300页

作者： WANG Yan-fen WANG Zheng-gang YU Hong-zhen School of lnformation and Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

From an analysis of the status of coal mine underground wireless communication, the application of UWB wireless communication system to underground coal mine is proposed. The basic composition of an UWB communication system and application in underground coal mines are introduced. The analyses show that, because of the transmission power being non-limitted in underground coal mines, the use of UWB in coal mines cannot only realize wireless access services of short distance high rate application for transmission of video monitoring signals, but also realize wireless access services of long distance low rate applications for mobile telephones in underground coal mines and parameters of working conditions monitoring, etc. It is emphasized on the simulation of a TH-PPM UWB communication system with traditional underground broadband model and ground CM1, CM3 model. It is shown that the traditional underground broadband model and ground CM1, CM3 models are not applicable to the UWB communication system in underground coal mines. It is necessary to conduct research on the propagation characteristics of UWB in coal mine tunnels, given the characteristics of the underground environment and to find the appropriate UWB model for underground coal mines.

关键词： ultra-wide band system simulation underground coal mine channel model characteristic of propagation.

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Experimental investigation of shale breakdown pressure under liquid nitrogen pre-conditioning before nitrogen fracturing

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International Journal of mining Science and technology 2021年第4期31卷 611-620页

作者： Yu Wu Jing Tao Jiehao Wang Yan Zhang Shuhua Peng State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China School of Mechanical Engineering Sichuan University of Science and EngineeringZigong 643000China School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 221116China Chevron Technical Center Houston 77002USA

Cryogenic fracturing with liquid nitrogen(LN_(2))offers the benefits of reducing the water consumption and adverse environmental impacts induced by water-based fracturing,as well as potentially enhancing the fracture *** performed a series of laboratory experiments to explore the key mechanisms governing the breakdown pressures of shale during cryogenic *** this study,cylindrical shale samples were pre-conditioned by exposing a borehole to low-temperature LN_(2) for a certain time period,and then,the samples were fractured using gaseous N_(2) under triaxial stress and a high reservoir *** effects of various key parameters on the breakdown pressure were investigated,including the duration of the low-temperature LN_(2) treatment,the confining pressure,the reservoir temperature,and the direction of the shale bedding relative to the borehole *** results demonstrate that the injection of low-temperature LN_(2) as a pre-fracturing fluid into a borehole can significantly reduce the breakdown pressure of the shale during subsequent nitrogen *** reduction in breakdown pressure can be further intensified by increasing the duration of the LN_(2) *** LN_(2) pre-conditioning,the breakdown pressure initially increases and then decreases with increasing reservoir *** LN_(2) pre-conditioning is applied,the breakdown pressure keeps decreasing with increasing reservoir *** the confining pressure increased,the breakdown pressure increased linearly in the tests with and without LN_(2) *** experimental results demonstrate that LN_(2) preconditioning before N_(2) fracturing is a promising waterless fracturing technique that reduces the breakdown pressure and enhances the fracture complexity.

关键词： Breakdown pressure Liquid nitrogen(LN_(2))pre-conditioning Nitrogen(N2)fracturing Thermal shock

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