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Underground Space 2024年第6期19卷 227-250页

作者： Min Hu Bingjian Wu Huiming Wu Liefeng Pei SILC Business School Shanghai UniversityShanghai 201800China SHU-SUCG Research centre for Building Industrialization Shanghai 201800China Shanghai Tunnel Engineering Co. Ltd.Shanghai 200032China

To solve the problem that current attitude planning methods do not fully consider the interaction and constraints among the shield,segmental tunnel ring,and geology,and cannot adapt to the changes in the actual engineering environment,or provide feasible long-term and short-term attitude planning,this paper proposes autonomous intelligent dynamic trajectory planning(AI-DTP)to provide tunnel ring and centimeter-layer planning targets for a self-driving shield to meet long-term accuracy and short-term ***-DTP introduces the Frenet coordinate system to solve the problem of inconsistent spatial representation of tunnel data,segmental tunnel ring location,and surrounding geological conditions,designs the long short-term memory attitude prediction model to accurately predict shield attitude change trend based on shield,tunnel,and geology,and uses a heuristic algorithm for trajectory ***-DTP provides ring-layer and centimeter-layer planning objectives that meet the needs of long-term accuracy and short-term correction of shield attitude *** the Hangzhou-Shaoxing Intercity Railroad Tunnel Project in China,the‘‘Zhiyu”shield equipped with the AI-DTP system was faster and more accurate than the manually controlled shield,with a smoother process and better quality of the completed tunnel.

关键词： Shield tunnel Trajectory planning Attitude control Self-driving Machine learning

Analysis of Calcined Red Mud Properties and Related Mortar Performances

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Fluid Dynamics & Materials Processing 2024年第5期20卷 901-913页

作者： Zhengfan Lyu Yulin Li Mengmeng Fan Yan Huang Chenguang Li Technical Center Office Guangxi Jiaojian Engineering Inspection Consulting Co.Ltd.Nanning530001China Technical Center Office Guangxi Road Construction Engineering Group Co.Ltd.Nanning530001China Nanning Road Construction Technology and Road Construction Materials Engineering Technology Research centre Guangxi Road Construction Engineering Group Co.Ltd.Nanning530001China

Red mud(RM)is a low-activity industrial solid waste,and its utilization as a resource is currently a hot *** this study,the micro characteristics of red mud at different calcination temperatures were analyzed using X-ray diffraction and scanning electron *** performance of calcined red mud was determined through mortar strength *** indicate that high-temperature calcination can change the mineral composition and microstructure of red mud,and increase the surface roughness and specific surface *** the optimal temperature of 700°C,the addition of calcined red mud still leads to a decrease in mortar strength,but its activity index and flexural coefficient increase by 16.2%and 11.9%with respect to uncalcined red mud,reaching values of 0.826 and 0.974,*** with the control group,the synergistic activation of calcined red mud with slag can increase the compressive and flexural strength of the mortar by 12.9%and 1.5%,reaching 8.7 and 62.4 MPa,***,the activity index and flexural coefficient of the calcined RM and GGBS(Ground Granulated Blast furnace Slag)mixtures also increase to 1.015 and 1.130,respectively.

关键词： Red mud slag thermal activation synergistic activation mortar test microscopic properties

Tribological properties of Al-GNP composites at elevated temperature

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Friction 2024年第5期12卷 1028-1041页

作者： Sunil POUDEL Rizwan BAJWA Yongde XIA Zakir KHAN Yi ZHANG Yanqiu ZHU College of Engineering Mathematics and Physical SciencesUniversity of ExeterExeterEX44QFUK European Technical centre Daido Metal Co.Ltd.Iliminster SomersetTA199PHUK

Lighter and more powerful next generation vehicles and other rotary machinery demand bearings to operate in harsher conditions for higher efficiency,and the continuous development of advanced low-wear and friction materials is thus becoming even more important to meet these *** aluminium composites reinforced with high performance lubricate phases such as graphene nanoplatelets(GNPs)are very promising and have been vigorously *** maintaining a low coefficient of friction(COF)and offering great strength against wear due to their self-lubricating capability,the solid lubricant like GNPs protect the bearing surface from wear damage and prevent change in metallurgical properties during temperature *** paper first studies the high-temperature tribological performance of aluminium matrix composites reinforced with GNP,consolidated via powder metallurgy,then elucidates their tribological *** report that the best tribological performance is achieved by the composite containing 2.0 wt%GNP,with an extraordinarily low COF of 0.09 and a specific wear rate of 3.5×10^(−2)mm^(3)·N^(−1)·m^(−1),which represent 75%and 40%reduction respectively,against the plain aluminium consolidated under identical *** in-track and out-of-track Raman analysis have confirmed the role of GNPs in creating a tribofilm on the counterpart surface which contributed to the excellent performance.

关键词： nanocomposite graphene nanoplatelet(GNP) tribology powder metallurgy

Using cemented paste backfill to tackle the phosphogypsum stockpile in China:A down-to-earth technology with new vitalities in pollutant retention and CO_(2) abatement

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1480-1499页

作者： Yikai Liu Yunmin Wang Qiusong Chen School of Resources and Safety Engineering Central South UniversityChangsha 410083China Department of Geosciences and CIRCe centre University of PaduaPadua 35129Italy Sinosteel Maanshan General Institute of Mining Research Co. Ltd.Ma'anshan 24300China

Phosphogypsum(PG),a hard-to-dissipate by-product of the phosphorus fertilizer production industry,places strain on the biogeochemical cycles and ecosystem functions of storage *** pervasive problem is already widespread worldwide and requires careful *** this study,we review the presence of potentially toxic elements(PTEs)in PG and describe their associations with soil properties,anthropogenic activities,and surrounding ***,we review different ex-/in-situ solutions for promoting the sustainable management of PG,with an emphasis on in-situ cemented paste backfill,which offers a cost-effective and highly scalable opportunity to advance the value-added recovery of ***,concerns related to the PTEs'retention capacity and long-term effectiveness limit the implementation of this ***,given that the large-scale demand for ordinary Portland cement from this conventional option has resulted in significant CO_(2) emissions,the technology has recently undergone additional scrutiny to meet the climate mitigation ambition of the Paris Agreement and China's Carbon Neutrality ***,we discuss the ways by which we can integrate innovative strategies,including supplementary cementitious materials,alternative binder solutions,CO_(2) mineralization,CO_(2) curing,and optimization of the supply chain for the profitability and sustainability of PG ***,to maximize the co-benefits in environmental,social,and economic,future research must bridge the gap between the feasibility of expanding these advanced pathways and the multidisciplinary needs.

关键词： cemented paste backfill phosphogypsum carbon dioxide mitigation potentially toxic elements solidification and stabilization

Gas hydrate saturation from NGHP 02 LWD data in the Mahanadi Basin

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Energy Geoscience 2024年第2期5卷 279-289页

作者： Uma Shankar Pradeep Kumar Yadav Sneha Devi Udham Singh Yadav Department of Geophysics Institute of ScienceBHUVaranasi221005India Oil and Natural Gas Corporation ltd. Gas Hydrate Research&Technology Centre(GHRTC)Panvel410221Navi MumbaiIndia

During the Indian National Gas Hydrate Program(NGHP)Expedition 02,Logging-while-drilling(LWD)logs were acquired at three sites(NGHP-02-11,NGHP-02-12,and NGHP-02-13)across the Mahanadi Basin in area *** applied rock physics theory to available sonic velocity logs to know the distribution of gas hydrate at site NGHP-02-11 and *** physics modeling using sonic velocity at well location shows that gas hydrate is distributed mainly within the depth intervals of 150-265 m and 100 -215 mbsf at site NGHP-02-11 and NGHP-02-13,respectively,with an average saturation of about 4%of the pore space and the maximum concentration of about 40%of the pore space at 250 m depth at site NGHP-02-11,and at site NGHP-02-13 an average saturation of about 2%of the pore space and the maximum concentration of about 20%of the pore space at 246 m depth,as gas hydrate is distributed mainly within 100-246 mbsf at this *** of gas hydrate estimated from the electrical resistivity method using density derived porosity and electrical resistivity logs from Archie's empirical formula shows high saturation compared to that from the sonic ***,estimates of hydrate saturation based on sonic P-wave velocity may differ significantly from that based on resistivity,because gas and hydrate have higher resistivity than conductive pore fluid and sonic P-wave velocity shows strong effect on gas hydrate as a small amount of gas reduces the velocity significantly while increasing velocity due to the presence of *** site NGHP-02-11,gas hydrate saturation is in the range of 15%e30%,in two zones between 150-180 and 245-265 *** NGHP-02-012 shows a gas hydrate saturation of 20%e30%in the zone between 100 and 207 *** NGHP-02-13 shows a gas hydrate saturation up to 30%in the zone between 215 and 246 *** observations from rock physics modeling and Archie’s approximation show the gas hydrate concentrations are relatively low(<4%of the pore space)at the sites of the

关键词： Mahanadi Basin Gas hydrate Sonic log Effective medium modeling Electrical resistivity log Archie’s analysis Gas hydrate saturation

Thermofluidic investigations of oil natural transformer:Closed-loop modelling and experimental validation

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High Voltage 2024年第1期9卷 230-240页

作者： Yuan Li Yiran Gao Chen Wang Chao Zhu Ying Li Yuankai Wang Guanjun Zhang State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina Electric Power Research Institute of State Grid Shaanxi Electric Power Co. Ltd.Xi'anChina TBEA Hengyang Transformer Co. Ltd.HengyangChina

Excessively high temperatures inside a power transformer can accelerate the ageing rate and even cause unplanned *** estimating the hot-spot temperature(HST)of a power transformer is important for regulating the load and ensuring long-term *** this study,a closed-loop model of a 110-kV product transformer with an oil natural/air forced(ONAF)cooling mode is built to predict HST,in which the compression ratio of windings,equivalent heat source and radiator geometry are *** to the flow field of the winding,the‘dead oil zone’and reverse oil flow are observed in the horizontal oil *** accuracy of the proposed model is experimentally validated by temperature-rise *** results show that the absolute errors between the measured results and simulation are below 5°C,and the average error is~2°***,the arrangements of windings and radiators are studied to enhance the oil *** adding 5 washers to the high-voltage winding,the average temperature can be decreased by 6°C compared with the case without a *** the radiator can also mitigate the characteristic temperatures,and the optimal height difference between the radiator and winding centre is suggested to be 0.66 m.

关键词： winding arrangement adding

Dynamic Analysis of A Deepwater Drilling Riser with A New Hang-off System

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China Ocean Engineering 2024年第1期38卷 29-41页

作者： LI Yan-wei LIU Xiu-quan WANG Jin-long CHEN Guo-ming CHANG Yuan-jiang SHENG Lei-xiang centre for Offshore Engineering and Safety Technology China University of PetroleumQingdao 266580China National Engineering Laboratory of Offshore Geophysical and Exploration Equipment China University of PetroleumQingdao 266580China China CNOOC Research Institute Co. Ltd.Beijing 100028China

The safety of risers in hang-off states is a vital challenge in offshore oil and gas engineering.A new hang-off system installed on top of risers is proposed for improving the security of *** approach leads to a challenging problem:coupling the dynamics of risers with a new hang-off system combined with multiple structures and complex *** accurately analyze the dynamic responses of the coupled system,a coupled dynamic model is established based on the Euler-Bernoulli beam-column theory and penalty function method.A comprehensive analysis method is proposed for coupled dynamic analysis by combining the finite element method and the Newmarkβ*** analysis program is also developed in MATLAB for dynamic *** simulation results show that the dynamic performances of the risers at the top part are significantly improved by the new hang-off system,especially the novel design,which includes the centralizer and articulation *** bending moment and lateral deformation of the risers at the top part decrease,while the hang-off joint experiences a great bending moment at the bottom of the lateral restraint area which requires particular attention in design and *** platform navigation speed range under the safety limits of risers expands with the new hang-off system in use.

关键词： deepwater drilling riser new hang-off system dynamic analysis finite element method penalty function method

Ba^(2+)/Ca^(2+)co-crosslinked alginate hydrogel filtration membrane with high strength,high flux and stability for dye/salt separation

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Chinese Chemical Letters 2024年第5期35卷 320-324页

作者： Ningning Gao Yue Zhang Zhenhao Yang Lijing Xu Kongyin Zhao Qingping Xin Junkui Gao Junjun Shi Jin Zhong Huiguo Wang SINOPEC Research Institute of Petroleum Processing CO. LTD.Beijing 100083China State Key Laboratory of Separation Membranes and Membrane Processes/National centre for International Joint Research on Separation Membranes Tiangong UniversityTianjin 300387China

Alginate is a natural polysaccharide *** filtration membranes prepared from alginate show excellent fouling resistance and controllable separation performance,but poor mechanical properties limit the use of algae *** this study,Ba^(2+)/Ca^(2+)co-crosslinked alginate(Ba/CaAlg)hydrogel membrane was prepared by cross-linking sodium alginate with a blend aqueous solution of barium ions and calcium ions,and the membrane was applied to the separation of dyes/salts from dyeing *** with the CaAlg membrane,the Ba/CaAlg hydrogel membrane exhibited more stable structure,and the mechanical properties and salt tolerance of the membrane were significantly *** flux of Ba/CaAlg membrane for methyl blue/sodium chloride mixed solution reached 43.5 L m^(−2) h^(−1),which was significantly higher than that of CaAlg ***,the Ba/CaAlg membrane showed higher dye rejection(>99.6%)and lower salt rejection(<8.2%).The structure of Ba/CaAlg membrane was preliminarily simulated by molecular dynamics,and the pore size and distribution of the membrane were *** Ba/CaAlg membrane has a broad application prospect in dyes/salts separation.

关键词： Alginate Filtration membrane Ba^(2+)/Ca^(2+)ion crosslinking Dye/salt separation Molecular dynamic simulation Hydrogel

Reinforcing Effect of Graphene in Epoxy Adhesives: Review

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Open Journal of Composite Materials 2024年第1期14卷 60-70页

作者： Fatehbahadur Purushottam Lodh Ravindra Vilas Indubai Gadhave Asian Paints ltd. Research & Technology centre Navi Mumbai India

Due to its great strength, hardness, and chemical resistance, epoxy adhesives are becoming more and more used. They continue to have drawbacks, nevertheless, such as poor thermal stability, and poor electrical conductivity. Two-dimensional graphene is a wonderful substance with exceptional qualities including high strength, high electrical conductivity, and large surface area. Because of these characteristics, graphene has been thoroughly researched for its prospective uses in a variety of industries, including electronics, energy storage, and biomedical engineering. The use of graphene as an additive in epoxy adhesives to enhance the characteristics of such materials is one of its promising uses. This paper reviewed the latest findings about graphene’s effects on epoxy adhesives. The various methods to produce graphene-epoxy composites and their improvements are discussed. This research additionally discusses the challenges associated with the production and processing of graphene-epoxy composites, as well as the mechanisms behind the improvements in mechanical, electrical, and thermal characteristics. The final section of this review discusses the challenges and prospective uses of graphene in epoxy adhesives in the future.

关键词： Graphene Epoxy Adhesives Composite Mechanical Properties

Exploring the synergy of the eyebrain connection:neuromodulation approaches for neurodegenerative disorders through transcorneal electrical stimulation

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Neural Regeneration Research 2024年第10期19卷 2097-2098页

作者： Antara Verma Stephen K.Agadagba Leanne Lai-Hang Chan Department of Electrical Engineering City University of Hong KongKowloonHong Kong Special Administrative RegionChina centre for Eye and Vision Research ltd. Hong Kong Special Administrative RegionChina Pennsylvania State University University ParkPAUSA

The connection and interaction between the eye and the brain are crucial to understanding brain disorders(Marchesi et al.,2021).Both the eye and the brain have a limited regenerative capacity as there are few progenitor cells,and nerve cells do not ***,neurodegeneration implicates irreversible damage to the central nervous system,as observed in several neurodegenerative diseases(Marchesi et al.,2021).

关键词： stimulation degenerative