检索结果-内蒙古大学图书馆

SSRN 2022年

作者： Li, Nan Liu, Tongcai Xiao, Shaoze Yin, Wenjun Zhang, Longlong Chen, Jiabin Wang, Yayi Zhou, Xuefei Zhang, Yalei State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and Engineering Tongji University Shanghai200092 China Shanghai Institute of Pollution Control and Ecological Security Shanghai200092 China

Thiosulfate (S2O32-) have been proven to be an effective promoter of Fenton-like reactions by accelerating the metal ions cycle. However, up to now, there is little information about the role of sulfur transformation and intermediate sulfur in the regulation of metal chemical cycle and reactive species production. Herein, free Cu(II) was selected as catalyst for the activation of H2O2. The introduction of S2O32- significantly enhanced the degradation of benzoic acid, which was 5.8 times higher than that of Cu(II)/H2O2 system. The kinetic model was developed to reveal the transformation of sulfur species and demonstrate that sulfides (i.e., HS-/S2-, S0 and S2O32-) were the dominant electron donor for the reduction of Cu(II) into Cu(I). Consequently, the reduction and complexation roles of S2O32- significantly resolve the rate-limiting step and broaden the pH range of in Fenton-like reactions. Evidence for the critical role of high-valent copper (Cu(III)) and HO• on BA degradation was obtained by scavengers experiments, electron paramagnetic resonance and fluorescent probes. Meanwhile, the Cu(II)/H2O2/S2O32- system also exhibited satisfactory anti-interference ability of the various matrix. Overall, this study offer mechanistic insight into sulfidation in Cu chemical cycle and Cu(III) generation, and highlight the potential of S2O32- for Fenton-like reactions to control pollutants. © 2022, The Authors. All rights reserved.

关键词： Sulfur compounds

Inactivation of Vancomycin-Resistant Enterococcus Faecalis and Degradation of Intracellular Vanb Gene Under Exposure to UV and UV/H202

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SSRN 2022年

作者： Gao, Rui Yu, Miao Xie, Jingni Sui, Minghao State Key Laboratory of Pollution Control and Resource Reuse Shanghai Institute of Pollution Control and Ecological Security School of Environmental Science and Engineering Tongji University 1239 Siping Road Shanghai200092 China

The proliferation of antibiotic resistance in water environment which may cause antibiotic therapy failure has attracted worldwide attention. However, the effects of UV-based advanced oxidation processes on inactivation of antibiotic resistant bacteria (ARB) and degradation of antibiotic resistance genes (ARGs) have not been well studied. This study aimed to comparatively investigate the removal efficacy in inactivating the vancomycin-resistant Enterococcus faecalis (VRE) and degrading its containing vanB gene under exposure to UV and UV/H 2 O 2 . The results showed that VRE was readily inactivated in both UV and UV/H 2 O 2 processes. Although UV/H 2 O 2 was only slightly superior to UV alone in VRE inactivation, it significantly inhibited the bacterial photoactivation and regrowth. UV/H 2 O 2 indeed achieved synergistic degradation of intracellular vanB (0.1-0.8 log), which could be further enhanced by increasing the UV intensity, lowering pH and adding H 2 O 2 in batches. The enhanced induction of ·OH resulted in the cell membrane damage, facilitating the entrance of excess ·OH and more efficiently oxidizing the released intracellular ARGs. Overall, the presence of humic acid inhibited the inactivation of VRE and degradation of vanB , while lower concentrations of humic acid (2.5-5 mg/L) could act as free radical initiator and slightly promoted vanB degradation in UV/H 2 O 2 process. Our findings suggested that UV/H 2 O 2 has more advantages on the control of ARB and intracellular ARGs compared to UV alone in drinking water treatment. © 2022, The Authors. All rights reserved.

关键词： Genes

Anisotropic surface roughness and shear behaviors of rough-walled plaster joints under constant normal load and constant normal stiffness conditions

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Journal of Rock Mechanics and Geotechnical engineering 2020年第2期12卷 338-352页

作者： Richeng Liu Sha Lou Xiaojing Li Guansheng Han Yujing Jiang State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221116China School of Engineering Nagasaki UniversityNagasaki852-8521Japan Department of Hydraulic Engineering Tongji UniversityShanghai200092China School of Civil Engineering Shandong Jianzhu UniversityJinan116024China State Key Laboratory of Mining Disaster Prevention and Control Shandong University of Science and TechnologyQingdao266590China

In this context,we experimentally studied the anisotropic mechanical behaviors of rough-walled plaster joints using a servo-controlled direct shear apparatus under both constant normal load(CNL)and constant normal stiffness(CNS)*** shear-induced variations in the normal displacement,shear stress,normal stress and sheared-off asperity mass are analyzed and correlated with the inclination angle of the critical waviness of joint *** results show that CNS condition gives rise to a smaller normal displacement due to the larger normal stress during shearing,compared with CNL *** CNL conditions,there is one peak shear stress during shearing,whereas there are no peak shear stress for some cases and two peaks for other cases under CNS conditions depending on the geometry of joint *** inclination angle of the critical waviness has been verified to be capable of describing the joint surface roughness and *** joint surface is more significantly damaged under CNS conditions than that under CNL *** increment of the inclination angle of the critical waviness,both the normal displaceme nt and shea red-off asperity mass increase,following power law functions;yet the coefficient of deternination under CNL conditions is larger than that under CNS *** is because the CNS condition significantly decreases the inclination angle of the critical waviness during shearing due to the larger degree of asperity degradation.

关键词： Joint Constant normal load(CNL) Constant normal stiffness(CNS) Shear anisotropy Surface roughness

Experimental Study on the Effects of Ultrasonic Excitation on Pore Structure of Water-Bearing Coal

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SSRN 2023年

作者： Liu, Qinhuai Huang, Qiming Wang, Gang Xie, Shuliang Wang, Enmao College of Safety and Environmental Engineering Shandong University of Science and Technology Qingdao266590 China Shandong University of Science and Technology Mine Disaster Prevention and Control Ministry of State Key Laboratory Breeding Base Qingdao266590 China

To study the effects of ultrasonic excitation on the pore structure of water-bearing coal in depth, ultrasonic excitation experiments were conducted with varied variables including ultrasonic excitation time, ultrasonic power, and fluid pressure on coal. The effects of sodium dodecyl sulfate (SDS) treatment and ultrasonic excitation were also compared. The coal samples treated under different conditions are characterized by low-temperature nitrogen adsorption and scanning electron microscopy for the analysis of variation of pore structure. The results show that ultrasonic excitation can significantly increase the pore volume and specific surface area of coal and damages the inner wall surfaces of the pore to different extents, making the pore inner surfaces rougher. However, the effect of ultrasonic excitation becomes weaker after the pore volume increases to a certain extent, resulting in more uniform pore size and volume distributions. Ultrasonic excitation time affects the pores with smaller size more significantly, and there is a time threshold effect. The volume and specific surface area of large pores and fractures show limited responses (or increases) to as the excitation time increased. The energy is mainly used for the fracturing and expanding the pores with smaller size. The effect of ultrasonic excitation on pore expansion is more obvious under the fluid pressures lower than 4 MPa. High fluid pressures weaken the fracturing and expanding effect of ultrasonic excitation on the pore structure of water-bearing coal. The ultrasonic power threshold effect is also observed. Once exceeding a certain value, further increasing the ultrasonic power does not dramatically affect the pore structure of water-containing coal. Ultrasonic excitation can enlarge the primary pores and fracture and generate secondary pores and fracture in coal. In contrast, the 0.85% SDS treatment is only able to clean the primary small pores, and no new pore structures are formed. © 2023, T

关键词： Coal

Investigation on Energy Characteristics of Shock Wave in Rock-Breaking Tests of High Voltage Electric Pulse Based on Hilbert-Huang Transform

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SSRN 2022年

作者： Zhang, Zhehao Nie, Baisheng Hou, Yanan Beijing100083 China State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety Engineering Chongqing University Chongqing400044 China

High Voltage Electric Pulse (HVEP) is a new type of coal seam and rock permeability enhancement technology. In this paper, large-scale rock breaking experiments were carried out using the self-developed HVEP system. The crack propagation process was recorded with a high-speed camera, and the instability characteristics of the rock fracture process were elucidated from the perspective of time-frequency-energy by the Hilbert-Huang transform (HHT) method. The results showed that an increase in voltage produced a stronger destructive effect on the rock. The peak energy of shock waves (SWs) appears at the instant of HVEP, and decreases rapidly within 0.1 s. The dominant frequency of SWs is distributed between 0 and 20 Hz, which is similar to the natural frequency of rock. Therefore, SWs can cause a strong resonance effect inside the rock. When the rock fractures, there will be obvious instability phenomena, including the increase of the frequency range of SWs vibration, and the shift of the main frequency of the vibration. At the same time, the effect of the derived wave will also be weakened by the fracture of the rock. © 2022, The Authors. All rights reserved.

关键词： Hilbert-Huang transform

Novel CD-MOF NIR-II fluorophores for gastric ulcer imaging

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Chinese Chemical Letters 2021年第10期32卷 3061-3065页

作者： Yishen Liu Yuzhen Yuzhen Tian Tian Wumei Wang Jinxia Nong Xue Qiao Fuchun Xu Jianfeng Gao Xuechuan Hong State Key Laboratory of Virology College of ScienceInnovation Center for Traditional Tibetan Medicine Modernization and Quality ControlMedical CollegeTibet UniversityLhasa 850000China Key Laboratory of Combinatorial Biosynthesis and Drug Discovery(MOE) Hubei Province Engineering and Technology Research Center for Fluorinated PharmaceuticalsWuhan University School of Pharmaceutical SciencesWuhan 430071China Shenzhen Institute of Wuhan University Wuhan 430071China Center for Animal Experiment Wuhan UniversityShenzhen 518057China

Gastric ulcers are one of the most common stomach diseases that often accompanied by inflammation,congestion,edema,scar tissue formation,and pyloric *** endoscopy and X-ray analysis of the upper GI tract have become the diagnostic procedure of choice for ***,conventional diagnosis technology is either invasive or ***,a novel CD-MOF NIR-II fluorophore(GPs-CH1055)was *** relative fluorophore intensity was largely consistent at various media and pH buffers,and it can swell into gel particles in solvents and be completely expelled from the gastrointestinal tract without being ***-CH1055 has been further evaluated in vivo,and exhibited strong retention effect on the gastric ulcer sites,bright NIR-II signals with high spatial and temporal ***,GPs-CH1055 shows great promise for realizing real-time gastric ulcer imaging and diagnosis.

关键词： Gastric ulcer NIR-II bioimaging Cyclodextrin metal-organic frameworks Real time Diagnose

Metagenomic Insights into the Influence of Thallium Spill on Sediment Microbial Community

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SSRN 2022年

作者： Chen, Sili Chen, Xiuli Wang, Ji Pan, Chaoyi Feng, Lishi Xie, Shuguang Guangzhou510655 China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing100871 China

Thallium (Tl) is an extremely toxic metal. The release of Tl into the natural environment can pose a potential threat to organisms. In addition, there has been no report on how sudden Tl spill influences the structure and function of the microbial community. This study explored the response of river sediment microbiome to a Tl spill. Residual T1 in the sediment significantly decreased bacterial community diversity. The increase in the abundance of Bacteroidetes in all Tl- impacted sediments suggested the advantage of Bacteroidetes to resist Tl pressure. After T1 spill, increase in both metal resistance genes (MRGs) and antibiotic resistance genes (ARGs) was observed in Tl-impacted sediments. The abundance of MRGs and ARGs was significantly correlated with sediment Tl concentration, implying the positive effect of Tl contamination on the proliferation of these resistance genes. Procrustes analysis suggested a significant congruence between profiles of MRGs and bacterial communities. Through LEfSe and co-occurrence network analysis, Trichococcus, Polaromonas, and Arenimonas were identified to be tolerant and resistant to Tl pollution. This study added new insights into the effect of Tl spill on microbial community and highlighted the role of heavy metal spill in the increase of both heavy metal and antibiotic resistance genes. © 2022, The Authors. All rights reserved.

关键词： Hazardous materials spills

Exergy Analysis of Electric Vehicle Heat Pump Air Conditioning System with Battery Thermal Management System

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Journal of Thermal Science 2020年第2期29卷 408-422页

作者： ZHANG Kexin LI Ming YANG Changhai SHAO Zhiyuan WANG Lihong State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130025China College of Automotive Engineering Jilin UniversityChangchun 130025China School of Energy and Power Engineering Xi’an Jiaotong UniversityXi’an 710049China FAW-Valeo Climate Control Systems Co.Ltd. Changchun 130011China

The exergy analysis of an electric vehicle heat pump air conditioning system(HPACS) with battery thermal management system was carried out by studying the exergy loss of each component. The results indicate that the compressor is the main source of system exergy loss in all operation conditions. The exergy loss distribution of HPACS is almost the same when the battery thermal management system integrated into the HPACS in cabin and battery mixed cooling mode and the system exergy loss was linearly related to the compressor speed in cooling modes. The performance of the HPACS is better than that of the positive temperature coefficient(PTC) heater in cabin heating mode. The degree of exergy efficiency improvement of the alternative mode was discussed at all operation conditions in cabin heating mode. The results indicate that the optimization effect using the electric vehicle HPACS to replace the PTC heater is obvious at lower compressor speed, surrounding temperature and internal condenser air flow rate.

关键词： electric vehicle heat pump exergy efficiency battery thermal management

Imbibition Behavior of Water on Coal Surface and the Impact of Surfactant

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SSRN 2023年

作者： Huang, Qiming Yan, Yuting Wang, Gang Li, Mingyang Yu, Bo Feng, Xu College of Safety and Environmental Engineering Shandong University of Science and Technology Qingdao266590 China Mine Disaster Prevention and Control-Ministry of State Key Laboratory Breeding Base Shandong University of Science and Technology Qingdao266590 China

Coal seam water injection is vital in mitigating dust pollution in coal mining operations. To investigate water imbibition and adsorption behavior on the coal surface following injection into coal seams, as well as the impact of surfactants, coal particles with sizes of 6–8 mm, 3–5 mm, and 0.4–0.85 mm were selected from the Dongtan Coal Mine in Shandong Province, China. Coal particle imbibition experiments were designed for coal particles at varying surfactant concentrations and temperatures, and molecular simulation was employed to examine the micro adsorption behavior of water within coal rock pores. The findings indicate that smaller coal particles exhibit significantly higher water absorption capacity compared to larger particles when ample water supply is present. This suggests that coal pore water absorption is inherently limited. Moreover, elevated formation temperatures hinder the wetting process of water injection. Importantly, introducing surfactants leads to the blockage of coal fractures, constriction of fracture channels, and restriction of the effective wetting range of coal seam water. Furthermore, the influence of sodium dodecyl sulfate is greater than that of cetyltrimethylammonium bromide. In low-temperature environments, surfactants exert a more prominent inhibitory effect on water injection wetting. These research findings provide valuable theoretical guidance for coal seam dust prevention efforts and water injection technology. © 2023, The Authors. All rights reserved.

关键词： Mining

A Calculation Method for Residual Stress of Cold Expanded Hole Based on Measured Springback

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SSRN 2023年

作者： Feng, Feng Zhao, Zirui Wang, Zibiao Li, Bo Lin, Xiaoxuan Zhang, Jianfu Feng, Pingfa Zhang, Xiangyu Division of Advanced Manufacturing Tsinghua Shenzhen International Graduate School Tsinghua University Shenzhen518055 China State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing100190 China Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Department of Mechanical Engineering Tsinghua University Beijing100084 China State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical Engineering Tsinghua University Beijing100084 China

Cold expansion can improve the fatigue life of bearing hole by introducing compressive residual stress. However, there is yet difficulty to measure the stress of hole wall because of the geometry and device limitations. In this study, a calculation method of residual stress based on the experimental-theoretical method is proposed by considering the circumferential symmetry of cold expansion. Stress and displacement are analyzed in the loading and unloading stages, and the measured springback is used in the unloading stage. The residual stress accuracy of the proposed method is significantly better than that of the classical elastic-plastic theory. Moreover, the effects of interference, expansion cycles and expansion speed on surface integrity and fatigue life are analyzed. It is found that interference is the most influencing parameter in coad expansion process, and there is a saturation effect of interference on improving the residual stress and fatigue life of bearing holes. © 2023, The Authors. All rights reserved.

关键词： Residual stresses