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Geoscience Frontiers 2024年第3期15卷 166-179页

作者： Shuoqin Hou di Li dengfa He yu Lu yu Zhen Hao yang dan Fan Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Accumulation Mechanism the Ministry of Educationand School of Energy ResourcesChina University of Geosciences(Beijing)Beijing 100083China

The Carboniferous to Permian tectono-sedimentary evolution of the southern Junggar area brings new insights into understanding the subduction-collision processes in the northern Tianshan *** geophysics,geochemistry,and geochronology approaches,this study investigates the Carboniferous-Permian strata in the southern Junggar *** results have revealed three distinct tectono-stratigraphic evolutionary stages,each marked by a distinctive volcano-sedimentary *** Early Carboniferous strata suggest intense volcanic activities in the southern Junggar *** the Late Carboniferous,the southern Junggar Basin was controlled by normal faulting in an extensional setting,receiving sedimentary inputs from the Junggar *** Lower Permian,unconformably overlying the Upper Carboniferous,was shaped by an extensional regime and is comprised by volcano-clastic sequences that received detritus from the Yili-Central Tianshan *** findings indicate that a Late Carboniferous forearc basin developed in the southern Junggar area,and it evolved into a post-collisional rift in the Early *** period marked a dynamic shift from bidirectional subduction(rollback)to the detachment of the North Tianshan oceanic *** propose that the collision between the YiliCentral Tianshan block and the Junggar terrane,along with the closure of the North Tianshan Ocean,likely occurred in the Late Carboniferous(ca.306-303 Ma).

关键词： Tectono-sedimentary evolution Tectonic transition Carboniferous-Permian Junggar Basin North Tianshan Ocean

Application of sparse S transform network with knowledge distillation in seismic attenuation delineation

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Petroleum Science 2024年第4期21卷 2345-2355页

作者： Nai-Hao Liu yu-Xin Zhang yang yang Rong-Chang Liu Jing-Huai Gao Nan Zhang School of Information and Communications Engineering Xi'an Jiaotong University School of Software Engineering Xi'an Jiaotong University PetroChina Research Institute of Petroleum Exploration and development (RIPEd) CNPC Research Institute of Exploration and development Yumen Oilfield Company CNPC

Time-frequency analysis is a successfully used tool for analyzing the local features of seismic ***, it suffers from several inevitable limitations, such as the restricted time-frequency resolution,the difficulty in selecting parameters, and the low computational efficiency. Inspired by deep learning,we suggest a deep learning-based workflow for seismic time-frequency analysis. The sparse S transform network(SSTNet) is first built to map the relationship between synthetic traces and sparse S transform spectra, which can be easily pre-trained by using synthetic traces and training labels. Next, we introduce knowledge distillation(Kd) based transfer learning to re-train SSTNet by using a field data set without training labels, which is named the sparse S transform network with knowledge distillation(Kd-SSTNet).In this way, we can effectively calculate the sparse time-frequency spectra of field data and avoid the use of field training labels. To test the availability of the suggested Kd-SSTNet, we apply it to field data to estimate seismic attenuation for reservoir characterization and make detailed comparisons with the traditional time-frequency analysis methods.

关键词： S transform deep learning Knowledge distillation Transfer learning Seismic attenuation delineation

Experiment of electrothermal stress for different types of end turn grading in the inverter-fed form-wound windings

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High Voltage 2024年第4期9卷 853-861页

作者： Wenhuan Zhao Peng Wang Yingwei Zhu yue Zhang Shuai yang Yan Liu yang Shi Chaofan yu Electrical Engineering department Sichuan UniversityChengduSichuanChina d&R Dongfang Electric Machinery Co.Ltd.DeyangSichuanChina

End turn grading with resistive–capacitive coupling experiences severe electrothermal stress when subjected to pulse width modulation(PWM)*** this paper,several experiments and simulations were carried conducted for four types of end turn *** of all,the temperature rise in the end turn grading increased with a decrease in rise *** the rise time was less than 500 ns,the temperature rise at the terminal was higher owing to the increased capacitive current coupled from the main wall ***,the current in the linear region exhibited minimal variation at different fundamental frequencies resulting in synchronized the temperature rise at the terminal and ***,the jump voltage was the key factor influencing temperature rise in end turn grading,confirmed by comparing different voltage ***,the transient behaviour of the maximum field in the stress grading material was determined at rise *** experimental and simulation results indicate that balancing and interdependently addressing the electrical and thermal stress protection in end turn grading is *** study aims to provide an experimental and theoretical foundation for an insulation system of inverter-fed rotating machinery operating under PWM voltage.

关键词： stress inverter insulation

Research on Bast Fiber Extracted from the White Bark of Three Species in the Genus Broussonetia

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Chinese Journal of Polymer Science 2024年第6期42卷 729-738页

作者： Shan-Shan Jin Si-Nong Wang Yan-Yan Huang Jing-yu Zhang Peng Liu Hui yu Hong-dong Zhang yu-Liang yang Institute for Preservation and Conservation of Chinese Ancient Books Fudan University LibraryFudan UniversityShanghai200433China State key laboratory of Molecular Engineering of polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China

Against the backdrop of a global paper resource shortage,there is a growing need to identify fast-growing tree species capable of producing long-lasting *** plant species namely Broussonetia kazinoki,Broussonetia papyrifera and hybrid paper mulberry,belong to the Broussonetia genus,were collected from China to study their white bark suitability for pulp and *** chemical composition revealed that the holocellulose content in Broussonetia kazinoki and Broussonetia papyrifera was more than 80%.The molecular weight distribution of several holocellulose/α-cellulose is observed by GPC,which allows us to better observe the changes of various components on the molecular *** yield,lignin,whiteness,and molecular weight of the pulps obtained by NaOH treatment were *** microscope was used to characterize the fiber length-width ratio and ***,the improvement of the fiber rigidity method based on the Kratky-Porod chain model makes it more theoretical and further reveals the influencing factors of fiber *** study demonstrates the high potentiality of these three species for papermaking applications.

关键词： Broussonetia genus Cellulose Alkaline pulping Kratky-Porod chain model Fiber rigidity

Predicting submerged vegetation drag with a machine learning-based method

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Journal of Hydrodynamics 2024年第3期36卷 534-545页

作者： Meng-yang Liu Hong-wu Tang Sai-yu yuan Jing Yan College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai UniversityNanjing210098China

Accurate estimation of the drag forces generated by vegetation stems is crucial for the comprehensive assessment of the impact of aquatic vegetation on hydrodynamic processes in aquatic *** coupling relationship between vegetation layer flow velocity and vegetation drag makes precise prediction of submerged vegetation drag forces particularly *** present study utilized published data on submerged vegetation drag force measurements and employed a genetic programming(GP)algorithm,a machine learning technique,to establish the connection between submerged vegetation drag forces and flow and vegetation *** using the bulk velocity,U,as the reference velocity scale to define the drag coefficient,C_(d),and stem Reynolds number,the GP runs revealed that the drag coefficient of submerged vegetation is related to submergence ratio(H^(*)),aspect ratio(d^(*)),blockage ratio(ψ^(*)),and vegetation density(λ).The relation between vegetation stem drag forces and flow velocity is implicitly embedded in the definition of C_(d).Comparisons with experimental drag force measurements indicate that using the bulk velocity as the reference velocity,as opposed to using the vegetation layer average velocity,U_(v),eliminates the need for complex iterative processes to estimate U_(v)and avoids introducing additional errors associated with U_(v)*** approach significantly enhances the model’s predictive capabilities and results in a simpler and more user-friendly formula expression.

关键词： drag coefficient genetic programming algorithm submerged vegetation flow resistance cylinder array

Analysis of mesoscopic mechanical dynamic characteristics of ballast bed with under sleeper pads

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Railway Engineering Science 2024年第1期32卷 107-123页

作者： Xiong yang Liuyang yu Xuejun Wang Zhigang Xu yu deng Houxu Li Faculty of Mechanical and Electrical Engineering Kunming University of Science and TechnologyKunmingChina yunnan Provincial Key Laboratory of Advanced Equipment Intelligent Manufacturing Technology KunmingChina

The meso-dynamical behaviour of a high-speed rail ballast bed with under sleeper pads(USPs)was *** geometrically irregular refined discrete element model of the ballast particles was constructed using 3d scanning techniques,and the 3d dynamic model of the rail-sleeper-ballast bed was constructed using the coupled discrete element method-multiflexible-body dynamics(dEM-MFBd)*** analyse the meso-mechanical dynamics of the ballast bed with USPs under dynamic load on a train and verify the correctness of the model in laboratory *** is shown that the deformation of the USPs increases the contact area between the sleeper and the ballast particles,and subsequently the number of contacts between *** the depth of the granular ballast bed increases,the contact area becomes larger,and the contact force between the ballast particles gradually *** the action of the elastic USPs,the contact forces between ballast particles are reduced and the overall vibration level of the ballast bed can be *** settlement of the granular ballast bed occurs mainly at the shallow position of the sleeper bottom,and the installation of the elastic USPs can be effective in reducing the stress on the ballast particles and the settlement of the ballast bed.

关键词： Under sleeper pads Ballast bed discrete element method Mesoscopic mechanical dynamic characteristics

Enhancing leaching efficiency of ion adsorption rare earths by ameliorating mass transfer effect of rare earth ions by applying an electric field

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Journal of Rare Earths 2024年第1期42卷 172-180,I0006页

作者： Lingbo Zhou Jie yang Shijie Kang Xiaojun Wang Hongdong yu Yinhua Wan Rare Earth Institute University of Science and Technology of ChinaHefei230000China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341000China Jiangxi Institute of Rare Earths Chinese Academy of SciencesGanzhou341000China School of Resources and Environment Engineering Jiangxi University of Science and TechnologyGanzhou341000China

Improving the seepage of leaching solution in the ore body and strengthening the mass transfer process of rare earth ions during in-situ leaching are two critical methods to improve the leaching efficiency of rare *** this study,2 wt%MgSO_(4)solution was used for the indoor simulated column leaching experiment on rare earth samples and an electric field was applied at both ends of the *** the effects of different intensities,initial application time and duration of the electric field on the rare earth leaching system and its mechanism were *** results show that compared with the single MgSO_(4)solution leaching,applying an electric field with a strength of 6 V/cm can save the leaching time of 30 min and increase the flow velocity of the rare earth leachate by 26.98%.Under the optimal conditions of applying an electric field with a strength of 6 V/cm for 20 min to the leaching system after10 min of the rare earth leachate flowing out,the leaching efficiency of sample increases from 81.20% to 86.05% with the increase of 4.85%.The mechanism analysis shows that when a direct current electric field is applied to the rare earth leaching system,rare earth ions rapidly change from disorderly movement with the seepage into faster and directional *** addition,the seepage of the leaching solution is also improved due to the increase of the cross-sectional area of the seepage channel,the polarized water molecules migrate directionally by force from the negative pole,and the movement of the hydrogen is generated by the electrolytic *** impo rtantly,based on the principle of in-situ leaching process,the layout of injection holes and deflector holes in this process provides a natural site for the electrode layout of the electric *** the simple equipme nt and the ope ration,the rare earth leaching process with the applied electric field has high feasibility in industrial application.

关键词： Ion adsorption rare earths Leaching system Electric field Mass transfer process Seepage

Radiation construction and excellent performances of Ag NPs/TiO_(2)/PEG/PVP multifunctional aerogel:Adsorption-photocatalytic degradation,photosensitive antibacterial and cytotoxicity

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Journal of Materiomics 2024年第3期10卷 585-593页

作者： Jin-yu yang dong-Liang Liu yue-Sheng Li Xiao-Jie yang Yi Liu School of Nuclear Technology and Chemistry&Biology/Hubei Key Laboratory of Radiation Chemistry and Functional Materials Hubei University of Science and TechnologyXianning437100HubeiChina Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province School of Chemistry and Chemical EngineeringWuhan University of Science and TechnologyWuhan437100HubeiChina College of Chemistry and Chemical Engineering Tiangong UniversityTianjin300387China

A cutting-edge method known as photocatalytic antibacterial technology can effectively eliminate drug-resistant bacterial strains and boast a wide-ranging antimicrobial *** the study,a novel Ag NPs/TiO_(2)/PEG/PVP(ATPP)aerogel photocatalyst was synthesized by an electron beam in-situ radiation method using polyethylene glycol(PEG),polyvinylpyrrolidone(PVP),AgNO_(3),and TiO_(2)as raw *** was characterized by X-ray diffraction spectroscopy(XRd),X-ray photoelectron spectroscopy(XPS)and solid ultraviolet diffuse reflectance spectroscopy(UV-Vis dRS).The results demonstrated that silver ions were reduced to silver nanoparticles by electron beam radiation *** the same time,the doping of silver nanoparticles(Ag NPs)enhanced visible-light *** degradation rate of methylene blue(MB)on 5%(in mass)ATPP could reach 81%under visible light for 180 *** coli(***)and Staphylococcus aureus(***)were used as model bacteria to explore the antimi-crobial properties of ATPP by zone of the inhibition method,plate counting method and live/dead bacterial *** antibacterial experiments showed that the antibacterial effect of ATPP was ***,MTT assay and Hoechst33342/PI double staining were used to prove that the composite had good *** aerogel photocatalytic material has the potential to decrease microbial presence in both medical and environmental settings,making it a valuable tool for such applications.

关键词： Ag NPs/TiO_(2)/PEG/PVP aerogel Electron beam radiation Adsorption-photocatalytic Photosensitive antibacterial Cytotoxicity

Effect of coral sand on the mechanical properties and hydration mechanism of magnesium potassium phosphate cement mortar

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第2期25卷 116-129页

作者： Hao LIU Huamei yang Houzhen WEI Jining yu Qingshan MENG Rongtao YAN College of Civil Engineering and Architecture Guilin University of TechnologyGuilin541004China Guangxi Key Laboratory of Geomechanics and Geotechnical Engineering Guilin University of TechnologyGuilin541004China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China School of Intelligent Construction Wuchang University of TechnologyWuhan430002China Hydraulic Concrete Institute China Three Gorges CorporationBeijing100038China The First Railway Survey and design Institute Group Corporation Xi’an710043China

damaged structures on coral islands have been spalling and cracking due to the dual corrosion of tides and *** ensure easy access to aggregate materials,magnesium potassium phosphate cement(MKPC)and coral sand(CS)are mixed to repair damaged structures on coral ***,CS is significantly different from land-sourced sand in mineral composition,particle morphology,and *** has a substantial impact on the hydration characteristics and macroscopic properties of MKPC ***,in this study we investigated the compressive strength,interfacial mechanical properties,and corrosion resistance of MKPC CS *** in the morphology,microstructure,and relative contents of hydration products were revealed by scanning electron microscope-energy dispersive spectrometer(SEM-EdS)and X-ray diffraction(XRd).The results indicated that the compressive strength increased linearly with the interfacial micro-hardness,and then stabilized after long-term immersion in pure water and Na2SO4 solution,showing excellent corrosion *** with MKPC river sand(RS)mortar,the hydration products of CS mortar were an intermediate product 6KPO2·8H2O with a relative content of 3.9%at 1 h and 4.1%at 12 *** hydration product MgKPO_(4)·6H_(2)O increased rapidly after 7-d curing,with an increased growth rate of 1100%.Our results showed that CS promoted the nucleation and formation of hydration products of MKPC,resulting in better crystallinity,tighter overlapping,and a denser interfacial transition *** results of this study provide technical support for applying MKPC mortar as a rapid repair material for damaged structures on coral islands.

关键词： Magnesium potassium phosphate cement(MKPC) Coral sand(CS) Mechanical properties Corrosion resistance Hydration mechanism

Molecular dynamics Simulation Studies on the Micromorphology and Proton Transport of Nafion/Ti_(3)C_(2)T_(x) Composite Membrane

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Chinese Journal of Polymer Science 2024年第3期42卷 373-387,I0009页

作者： Zhi-yue Han Su-Peng Pei Chun-yang yu Yong-Feng Zhou School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai 201418China School of Chemistry&Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgingShanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Green and High-end Utilization of Salt Lake Resources Chinese Academy of SciencesXining 810008China

The perfluorosulfonic acid(PFSA) membrane doped with two-dimensional conductive filler Ti_(3)C_(2)T_(x) is a fuel cell proton exchange membrane with high application potential. Experimental studies showed that the proton conductivity of Nafion/Ti_(3)C_(2)T_(x) composite membrane is improved significantly compared with that in pure Nafion. However, the microscopic mechanism of doping on the enhancement of membrane performance is remain unclear now. In this work, molecular dynamics simulation was used to investigate the microscopic morphology and proton transport behaviors of Nafion/Ti_(3)C_(2)T_(x) composite membrane at the molecular level. The results shown that there were significant differences about the diffusion kinetics of water molecules and hydroxium ions in Nafion/Ti_(3)C_(2)T_(x) at low and high hydration levels in the nanoscale *** the increase of water content, Ti_(3)C_(2)T_(x) in membrane was gradually surrounded by ambient water molecules to form a hydration layer, and forming a relatively continuous proton transport channel between Nafion polymer and Ti_(3)C_(2)T_(x) monomer. The continuous proton transport channel could increase the number of binding sites of proton and thus achieving high proton conductivity and high mobility of water molecules at higher hydration level. The current work can provide a theoretical guidance for designing new type of Nafion composite membranes.

关键词： Nafion/Ti_(3)C_(2)T_(x)composite membrane Proton transport Molecular dynamics simulation