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Effects of acid drainage from abandoned coal mines on the microbial community of Shandi River sediment,Shanxi Province

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International Journal of Coal Science & Technology 2021年第4期8卷 756-766页

作者： Di Chen Qiyan Feng Wenbo Li yuan Song Chunhong Zhao Collaborative Innovation Center for Resource Utilization and Ecological Restoration of Old Industrial Base China University of Mining and TechnologyXuzhou 221116China School of Environment Science and Spatial Informatics China University of Mining and TechnologyXuzhou 221116China Institute of Karst Geology of Chinese Academy of Geology Sciences Guilin 541004China

The discharge of acid mine drainage from abandoned high sulfur(S)coal mines has caused serious pollution in the Shandi River,Yangquan,Shanxi *** determine the impact of long-term acid mine drainage on the microorganisms in the river,we collected river sediments from a polluted tributary(Group P)and the mainstream of Shandi River(Group R)to study the bacterial diversity and community *** results showed that the tributary was seriously polluted by acid drainage from abandoned coal mines,with the pH value of the sediment being<2.5,resulting in the low bacterial richness and diversity of the tributary *** Fe-and S-metabolizing bacteria,such as Metallibacterium,Acidiphilium,and Acidithiobacillus,were the dominant genera in Group P samples,while the Group R was dominated by the neutral anaerobic iron-reducing bacteria Geothrix and *** of principal co-ordinates analysis(PCoA)revealed that the bacterial communities are significantly different between groups P and R,and the significant different species were mainly attributed to phylum Proteobacteria,Actinobacteria,and *** distribution of the microbial community is mainly influenced by pH,and the Fe and Cd ***,the dominant genus,is negatively correlated with pH(R^(2)=-0.95)and positively correlated with Fe(R^(2)=0.99),while Geothrix and Geobacter,are mainly affected by the heavy *** study determined the impact of river pollution caused by abandoned coal mine drainage,especially on the microbial diversity and community composition within the river sediment.

关键词： Abandoned coal mine Acid mine drainage Bacterial community River sediment PCoA

Privacy preserving divisible double auction with a hybridized TEE‑blockchain system

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Cybersecurity 2021年第1期4卷 580-593页

作者： Bingyu Liu Shangyu Xie yuanzhou Yang Rujia Wang yuan Hong Illinois Institute of Technology 10 West 35th StreetChicagoIL 60616USA

Double auction mechanisms have been designed to trade a variety of divisible resources(e.g.,electricity,mobile data,and cloud resources)among distributed *** such divisible double auction,all the agents(both buyers and sellers)are expected to submit their bid profiles,and dynamically achieve the best *** practice,these agents may not trust each other without a market ***,smart contract is extensively used to ensure digital agreement among mutually distrustful *** consensus protocol helps the smart contract execution on the blockchain to ensure strong integrity and ***,severe privacy risks would emerge in the divisible double auction since all the agents should disclose their sensitive data such as the bid profiles(i.e.,bid amount and prices in different iterations)to other agents for resource allocation and such data are replicated on all the nodes in the ***,the consensus requirements will bring a huge burden for the blockchain,which impacts the overall *** address these concerns,we propose a hybridized TEE-Blockchain system(system and auction mechanism co-design)to privately execute the divisible double *** designed hybridized system ensures privacy,honesty and high efficiency among distributed *** bid profiles are sealed for optimally allocating divisible resources while ensuring truthfulness with a Nash ***,we conduct experiments and empirical studies to validate the system and auction performance using two real-world applications.

关键词： Privacy Truthfulness Blockchain Smart contract TEE Auction design

Indoor positioning based on tightly coupling of PDR and one single Wi-Fi FTM AP

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Geo-Spatial Information Science 2023年第3期26卷 480-495页

作者： yuan Wu Ruizhi Chen Wenju Fu Wei Li Haitao Zhou Guangyi Guo State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing(LIESMARS)Wuhan UniversityWuhanChina

The indoor positioning system is now an important technique as part of the Internet-of-Things(IoT)*** indoor positioning techniques,multiple Wi-Fi Access Points(APs)-based positioning systems have been researched a *** is a lack of research focusing on the scene where only one Wi-Fi AP is *** work proposes a hybrid indoor positioning system that takes advantage of the Fine-Timing Measurements(FTM)technique that is part of the IEEE 802.11mc standard,introduced back in *** system uses one single Wi-Fi FTM AP and takes advantage of the built-in inertial sensors of the smartphone to estimate the device’s *** explore both Loosely Coupled(LC)and Tightly Coupled(TC)integration schemes for the sensors’data *** results show that the proposed methods can achieve an average positioning accuracy of about 1 m without knowing the initial *** with the LC integration method,the median error accuracy of the proposed TC fusion algorithm has improved by more than 52%and 67%,respectively,in the two experiments we set up.

关键词： Indoor positioning Wi-Fi Fine Time Measurement(FTM)/Round Trip Time(RTT) Tightly Coupled(TC)integration Pedestrian Dead Reckoning(PDR) Extended Kalman Filter(EKF)

A comparative study on design standards of screw conveyors in China,Germany,and the USA-Part Ⅱ:Discrete element method

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Particuology 2024年第9期92卷 113-125页

作者： yuan Tan Michael Rackl Weijie Yang Johannes Fottner Wenjun Meng Stephan Kessler Technical University of Munich Chair for Materials HandlingMaterial FlowLogisticsGarchingGermany Ibracon–Ingenieurbüro Dr.-Ing.Rackl ZornedingGermany School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuanChina

This part of the study aims to evaluate the advantages and disadvantages of technical standards of screw conveyors in China,Germany,and the USA for industrial *** source or determination method of empirical coefficients as well as the theoretical foundation of dimensioning-relevant diagrams in these standards is not explicitly documented in the ***,instead of less efficient on-site tests,the numerical simulation by discrete element method is *** on the geometrical and operational designs determined in three standards for horizontal,slightly inclined,and vertical conveyance of three representative bulk solids(barley,lignite,and sand),the potential influencing factors are *** constant particle and contact parameters,the potential deviations caused by particle models are ***,the accuracy of power consumption calculation of each standard and the divergence between accessible and required mass flows is comprehensively assessed based on the analysis of simulated *** main conclusions are drawn:(1)Particle fall back is barely considered by all three standards and leads to overestimated mass throughput;(2)The decrease in mass throughput caused by an increasing degree of filling can be compensated by slowing down the rotational speed.

关键词： Discrete element method Design standard Screw conveyor Screw auger Bulk solid

Palladium nanoclusters immobilized on defective nanodiamond-graphene core-shell supports for semihydrogenation of phenylacetylene

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Journal of Energy Chemistry 2019年第6期28卷 31-36页

作者： Fei Huang Zhimin Jia Jiangyong Diao Hua yuan Dangsheng Su Hongyang Liu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026AnhuiChina College of Chemistry Chongqing Normal UniversityChongqing 401331China

We report a nanocarbon material with nanodiamond(ND) core and graphene shell(ND@G) as a support for Pd nanocatalysts. The designed catalyst performed good selectivity of styrene(85.2%) at full conversion of phenylacetylene and superior stability under mild conditions. Supported Pd catalysts are characterized by means of high resolution transmission electron microscopy(HRTEM), Raman, X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS) and H2 temperature-programmed reduction(H2-TPR).The results clearly show that formation of the strong metal-support interaction(SMSI) between Pd nanoclusters and the defective graphene shell helpfully modifies the selectivity and stability of the Pd-based catalysts.

关键词： Selective hydrogenation Palladium nano clusters Nanocarbon support Liquid-phase hydrogenation

Wave effects on the anti-liquefaction of the seabed around composite bucket foundation of offshore wind turbines

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Journal of Hydrodynamics 2021年第6期33卷 1291-1302页

作者： Li-hua Wang Jin-feng Zhang Run-bo Cai Jing-yuan Li State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072China Key Laboratory of Earthquake Engineering Simulation and Seismic Resilience of China Earthquake Administration Tianjin UniversityTianjin 300350China

By using the open-source software OpenFOAM and the grid generation tool the integrated computer engineering and manufacturing code for computational fluid dynamics(ICEM CFD),a computational fluid dynamics-computational structural dynamics(CFD-CSD)coupling model is *** dynamic response and the liquefaction of the seabed around the composite bucket foundation of the offshore wind turbines in the Xiangshui area of Jiangsu Province are *** pore water pressure,the effective stress,the liquefaction depth and the anti-liquefaction effect of the overlying stones are *** is shown that the seabed around the composite bucket foundation will be liquefied under 50 year return waves,the liquefaction width is approximately 1/3 of the wavelength,and the maximum liquefaction depth is approximately 1/4 of the wave *** addition,the overlying stones provide an effective anti-liquefaction ***,less porous overlying stones have a better anti-liquefaction effect.

关键词： Offshore wind turbine composite bucket foundation wave anti-liquefaction overlying stones

Methane production from rice straw carbon in five different methanogenic rice soils:rates,quantities and microbial communities

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Acta Geochimica 2020年第2期39卷 181-191页

作者： Quan yuan Xiaozhen Huang Junpeng Rui Shaojun Qiu Ralf Conrad State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Max Planck Institute for Terrestrial Microbiology 35043 Marburg.Germany Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Regions(Ministry of Education) Guizhou UniversityGuiyang 550025.China State Key Laboratory of Grassland Agro-Ecosystem.Institute of Innovation Ecology Lanzhou UniversityLanzhou 730000China National Engineering Laboratory for Improving Quality of Arable Land.Ministry of Agriculture Key Laboratory of Plant Nutrition and Fertilizers Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China

The input of organic substances(e.g.,rice straw)in rice field soils usually stimulates the production and emission of the greenhouse gas methane(CH4).However,the amount of CH4 derived from the applied rice straw,as well as the response of bacterial and archaeal communities during the methanogenic phase,are poorly understood for different rice field *** this study,samples of five different rice soils were amended with 13^C-labeled rice straw(RS)under methanogenic *** after RS addition,the RS-derived CH4 production rates were higher in soils(Uruguay,Fuyang)that possessed a stronger inherent CH4 production potential compared with other soils with lower inherent potentials(Changsha,the Philippines,Vercelli).However,soils with higher inherent potential did not necessarily produce higher amounts of CH4 from the RS applied,or vice *** PCR showed copy numbers of both bacteria and methanogens increased in straw-amended ***-throughput sequencing of 16 S rRNA genes showed distinct bacterial communities among the unamended soil samples,which also changed differently in response to RS ***,RS addition generally resulted in all the rice field soils in a relative increase of primary fermenters belonging to Anaerolineaceae and ***,RS addition also generally resulted in a relative increase of Methanosarcinaceae and/or *** results suggest that after RS addition the total amounts of RSderived CH4 are distinct in different rice field soils under methanogenic ***,there are potential core bacterial populations that are often involved in primary fermentation of RS under methanogenic conditions.

关键词： 13^C-labeled rice straw Methane production Rice field soil Microbial community

Synthesis of Ultralow-Density Polyethylene Elastomers Using Triarylnaphthyl Iminopyridyl Ni(II)Catalysts

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Precision Chemistry 2024年第10期2卷 553-558页

作者： Wenbin yuan Shengyu Dai Anhui Laboratory of Molecule-Based Materials Key Laboratory of Functional Molecular SolidsMinistry of EducationSchool of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002China Yueyang Xingchang Petro-Chemical Co. Ltd.Yueyang 414021China

Recently,the chain-walking ethylene polymerization strategy has garnered widespread attention as an efficient and straightforward method for preparing polyolefin *** this study,a series of 2,4,8-triarylnaphthyl iminopyridyl nickel catalysts were synthesized and used in ethylene *** catalysts demonstrated moderate catalytic activity(105 g mol^(−1) h^(−1)),producing high-molecular-weight(up to 145.5 kg/mol)polyethylene materials with high branching degrees(75−95/1000C)and correspondingly low melting *** analysis using 13C NMR spectroscopy revealed that the polyethylenes primarily featured methyl and long-chain *** testing of the polyethylene samples obtained from catalysts Ni1−Ni3 exhibited moderate stress at break(4.64−6.97 MPa)coupled with a very high strain at break(1650−3752%),indicating their very good ***,these polyethylenes showcased great elastic recovery abilities,with strain recovery values ranging from 72%to 85%.In contrast,the polyethylene produced by Ni4 displayed notably inferior tensile strength(0.16 MPa)and tensile recovery(43%).To the best of our knowledge,this study represents the inaugural utilization of a nickel iminopyridyl catalyst in the preparation of a polyethylene thermoplastic elastomer.

关键词： 2,4,8-triarylnaphthyl iminopyridyl Ni(Ⅱ)catalysts polyolefin elastomers ultralow density chain-walking

Evaluation of Surface Roughness of Aluminum Alloy in Burnishing Process Based on Chaos Theory

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Chinese Journal of Mechanical Engineering 2023年第1期36卷 90-103页

作者： Zhipeng yuan Zhenyu Zhou Zhiguo Jiang Zeyu Zhao Cong Ding Zhongyu Piao College of Mechanical Engineering Zhejiang University of TechnologyHangzhou310012ZhejiangChina Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou310012China

Burnishing experiments with different burnishing parameters were performed on a computer numerical control milling machine to characterize the surface roughness of an aluminum alloy during *** chaos theory was employed to investigate the nonlinear features of the burnishing *** experimental results show that the power spectrum is broadband and continuous,and the Lyapunov exponentλis positive,proving that burnishing has chaotic *** chaotic characteristic parameter,the correlation dimension D,is sensitive to the time behavior of the system and is used to establish the corresponding relationship with the surface *** correlation dimension was the largest,when the surface roughness was the ***,when the correlation dimension curve decreases,the roughness curve *** correlation dimension and surface roughness exhibit opposite variation *** higher the correlation dimension,the lower the surface *** surface roughness of the aluminum alloy can be characterized online by calculating the correlation dimension during burnishing.

关键词： Aluminum alloy burnishing Power spectrum Correlation dimension Lyapunov exponent Surface roughness