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Gold solubility in silicate melts and fluids:Advances from high-pressure and high-temperature experiments 被引量:1
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作者 Xingcheng LIU Ting XU +2 位作者 Xiaolin XIONG Li LI Jianwei LI 《Science China Earth Sciences》 SCIE EI CSCD 2021年第9期1481-1491,共11页
The solubility of Au in silicate melts and fluids governs the enrichment and migration of Au during the formation of magmatic-hydrothermal Au deposits.Large Au deposits require vast amounts of Au to migrate from the u... The solubility of Au in silicate melts and fluids governs the enrichment and migration of Au during the formation of magmatic-hydrothermal Au deposits.Large Au deposits require vast amounts of Au to migrate from the upper mantle-lower crust to the shallow crust,and high Au solubility in magma and hydrothermal fluid facilitates the formation of Au-rich magma and fluid in the crust and mantle source and efficient transport.This paper reviews recent high-pressure and high-temperature experimental studies on Au species in magmas and hydrothermal fluids,the partitioning behavior of Au between silicate melts and fluids,and the effects of temperature,pressure,oxygen fugacity,sulfur fugacity,silicate melt composition,and volatiles(H2O,CO2,chlorine,and sulfur)on the solubility of Au in magma.We show that the solubility of Au in magma is largely controlled by the volatiles in the magma:the higher the content of reduced sulfur(S2-and HS-)in the magma,the higher the solubility of Au.Under high-temperature,high-pressure,H2O-rich,and intermediate oxygen fugacity conditions,magma can dissolve more reduced sulfur species,thus enhancing the ability of the magma to transport Au.If the ore-forming elements of the Au deposits in the North China Craton originate from mantle-derived magmas and fluids,we can conclude,in terms of massive Au migration,that these deep Au-rich magmas might have been generated under H2 O-rich and moderately oxidized conditions(S2-coexists with S6+).The big mantle wedge beneath East Asia was metasomatized by melts and fluids from the dehydration of the Early Cretaceous paleo-Pacific stagnant slab,which not only caused thinning of the North China Craton,but also created physicochemical conditions favorable for massive Au migration. 展开更多
关键词 Magmatic-hydrothermal gold deposits Gold solubility Sulfur solubility VOLATILES High-pressure and high-temperature experiments
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Experimental study on reactions between alkaline basaltic melt and orthopyroxenes: constraints on the evolution of lithospheric mantle in the North China Craton
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作者 Hanqi He Mingliang Wang Hongfeng Tang 《Acta Geochimica》 EI CAS CSCD 2024年第2期354-365,共12页
The experimental results of the reactions between an alkaline basaltic melt and mantle orthopyroxenes under high-temperature and high-pressure conditions of 1300–1400℃ and 2.0–3.0 GPa using a six-anvil apparatus ar... The experimental results of the reactions between an alkaline basaltic melt and mantle orthopyroxenes under high-temperature and high-pressure conditions of 1300–1400℃ and 2.0–3.0 GPa using a six-anvil apparatus are reported in this paper.The reactions are proposed to simulate the interactions between melts from the asthenospheric mantle and the lithospheric mantle.The starting melt in the experiments was made from the alkaline basalt occurring in Fuxin,Liaoning Province,and the orthopyroxenes were separated from the mantle xenoliths in Damaping,Hebei Province.The results show that clinopyroxenes were formed in all the reactions between the alkaline basaltic melt and orthopyroxenes under the studied P–T conditions.The formation of clinopyroxene in the reaction zone is mainly controlled by dissolution–crystallization,and the chemical compositions of the reacted melt are primarily infl uenced by the diff usion eff ect.Temperature is the most important parameter controlling the reactions between the melt and orthopyroxenes,which has a direct impact on the melting of orthopyroxenes and the diff usion of chemical components in the melt.Temperature also directly controls the chemical compositions of the newly formed clinopyroxenes in the reaction zone and the reacted melt.The formation of clinopyroxenes from the reactions between the alkaline basaltic melt and orthopyroxenes can result in an increase of CaO and Al_(2)O_(3) contents in the rocks containing this mineral.Therefore,the reactions between the alkaline basaltic melt from the asthenospheric mantle and orthopyroxenes from the lithospheric mantle can lead to the evolution of lithospheric mantle in the North China Craton from refractory to fertile with relatively high CaO and Al 2 O 3 contents.In addition,the reacted melts in some runs were transformed from the starting alkaline basaltic into tholeiitic after reactions,indicating that tholeiitic magma could be generated from alkaline basaltic one via reactions between the latter and orthopyroxene. 展开更多
关键词 Alkaline basaltic melt ORTHOPYROXENE Melt–mineral reaction high-temperature and high-pressure experiment Genesis of basalt Evolution of lithospheric mantle in the North China Craton
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Harness High-Temperature Thermal Energy via Elastic Thermoelectric Aerogels
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作者 Hongxiong Li Zhaofu Ding +5 位作者 Quan Zhou Jun Chen Zhuoxin Liu Chunyu Du Lirong Liang Guangming Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期196-210,共15页
Despite notable progress in thermoelectric(TE)materials and devices,developing TE aerogels with high-temperature resistance,superior TE performance and excellent elasticity to enable self-powered high-temperature moni... Despite notable progress in thermoelectric(TE)materials and devices,developing TE aerogels with high-temperature resistance,superior TE performance and excellent elasticity to enable self-powered high-temperature monitoring/warning in industrial and wearable applications remains a great challenge.Herein,a highly elastic,flame-retardant and high-temperature-resistant TE aerogel,made of poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate)/single-walled carbon nanotube(PEDOT:PSS/SWCNT)composites,has been fabricated,displaying attractive compression-induced power factor enhancement.The as-fabricated sensors with the aerogel can achieve accurately pressure stimuli detection and wide temperature range monitoring.Subsequently,a flexible TE generator is assembled,consisting of 25 aerogels connected in series,capable of delivering a maximum output power of 400μW when subjected to a temperature difference of 300 K.This demonstrates its outstanding high-temperature heat harvesting capability and promising application prospects for real-time temperature monitoring on industrial high-temperature pipelines.Moreover,the designed self-powered wearable sensing glove can realize precise wide-range temperature detection,high-temperature warning and accurate recognition of human hand gestures.The aerogel-based intelligent wearable sensing system developed for firefighters demonstrates the desired self-powered and highly sensitive high-temperature fire warning capability.Benefitting from these desirable properties,the elastic and high-temperature-resistant aerogels present various promising applications including self-powered high-temperature monitoring,industrial overheat warning,waste heat energy recycling and even wearable healthcare. 展开更多
关键词 THERMOELECTRICS AEROGEL SELF-POWERED high-temperature monitoring high-temperature warning
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Synergistic effect of Zr and Mo on precipitation and high-temperature properties of Al-Si-Cu-Mg alloys
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作者 Chao Gao Bing-rong Zhang +2 位作者 Yin-ming Li Zhi-ming Wang Xiang-bin Meng 《China Foundry》 SCIE EI CAS CSCD 2024年第1期71-81,共11页
This study focuses on finding a solution to the sharp decline in mechanical properties of Al-Si-Cu-Mg alloys due to rapid coarsening of traditional intermediate phases at high temperature.A new type of modified al oy,... This study focuses on finding a solution to the sharp decline in mechanical properties of Al-Si-Cu-Mg alloys due to rapid coarsening of traditional intermediate phases at high temperature.A new type of modified al oy,to be used in automobile engines at high temperatures,was prepared by adding Zr and Mo into Al-Si-Cu-Mg alloy.The synergistic effects of Zr and Mo on the microstructure evolution and high-temperature mechanical properties were studied.Results show that the addition of Zr and Mo generates a series of intermetallic phases dispersed in the alloy.They can improve the strength of the alloy by hindering dislocation movement and crack propagation.In addition,some nano-strengthened phases show coherent interfaces with the matrix and improve grain refinement.The addition of Mo greatly improves the heat resistance of the alloy.The extremely low diffusivity of Mo enables it to improve the thermal stability of the intermetallic phases,inhibit precipitation during aging,reduce the size of the precipitates,and improve the heat resistance of the alloy. 展开更多
关键词 Al-Si-Cu-Mg alloy high-temperature properties Zr-Mo-rich intermetallics nano-strengthening phases
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HZSM-5 zeolites undergoing the high-temperature process for boosting the bimolecular reaction in n-heptane catalytic cracking
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作者 Chenggong Song Zhenzhou Ma +6 位作者 Xu Hou Hao Zhou Huimin Qiao Changchang Tian Li Yin Baitang Jin Enxian Yuan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期136-144,共9页
High-temperature treatment is key to the preparation of zeolite catalysts.Herein,the effects of hightemperature treatment on the property and performance of HZSM-5 zeolites were studied in this work.X-Ray diffraction,... High-temperature treatment is key to the preparation of zeolite catalysts.Herein,the effects of hightemperature treatment on the property and performance of HZSM-5 zeolites were studied in this work.X-Ray diffraction,N2physisorption,27Al magic angle spinning nuclear magnetic resonance(MAS NMR),and temperature-programmed desorption of ammonia results indicated that the hightemperature treatment at 650℃ hardly affected the inherent crystal and texture of HZSM-5zeolites but facilitated the conversion of framework Al to extra-framework Al,reducing the acid site and enhancing the acid strength.Moreover,the high-temperature treatment improved the performance of HZSM-5 zeolites in n-heptane catalytic cracking,promoting the conversion and light olefins yield while inhibiting coke formation.Based on the kinetic and mechanism analysis,the improvement of HZSM-5 performance caused by high-temperature treatment has been attributed to the formation of extra-framework Al,which enhanced the acid strength,facilitated the bimolecular reaction,and promoted the entropy change to overcome a higher energy barrier in n-heptane catalytic cracking. 展开更多
关键词 HZSM-5 N-HEPTANE Catalytic cracking high-temperature treatment Extra-framework Al
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Computational Experiments for Complex Social Systems:Experiment Design and Generative Explanation
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作者 Xiao Xue Deyu Zhou +5 位作者 Xiangning Yu Gang Wang Juanjuan Li Xia Xie Lizhen Cui Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期1022-1038,共17页
Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a nove... Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a novel approach for the design,analysis,management,control,and integration of CPSS,which can realize the causal analysis of complex systems by means of“algorithmization”of“counterfactuals”.However,because CPSS involve human and social factors(e.g.,autonomy,initiative,and sociality),it is difficult for traditional design of experiment(DOE)methods to achieve the generative explanation of system emergence.To address this challenge,this paper proposes an integrated approach to the design of computational experiments,incorporating three key modules:1)Descriptive module:Determining the influencing factors and response variables of the system by means of the modeling of an artificial society;2)Interpretative module:Selecting factorial experimental design solution to identify the relationship between influencing factors and macro phenomena;3)Predictive module:Building a meta-model that is equivalent to artificial society to explore its operating laws.Finally,a case study of crowd-sourcing platforms is presented to illustrate the application process and effectiveness of the proposed approach,which can reveal the social impact of algorithmic behavior on“rider race”. 展开更多
关键词 Agent-based modeling computational experiments cyber-physical-social systems(CPSS) generative deduction generative experiments meta model
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Experimental Investigation on Vertical Hydraulic Transport of Ores in Deepsea Mining
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作者 LIU Lei LIU Jian-cheng +2 位作者 LI Xin XU Li-xin ZHANG Xiu-zhan 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期42-53,共12页
Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on land.Vertical hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for... Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on land.Vertical hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for industrial applications.In the present study,an indoor model test of the vertical hydraulic transport of particles was conducted.A noncontact optical method has been proposed to measure the local characteristics of the particles inside a vertical pipe,including the local concentration and particle velocity.The hydraulic gradient of ore transport was evaluated with various particle size distributions,particle densities,feeding concentrations and mixture flow velocities.During transport,the local concentration is larger than the feeding concentration,whereas the particle velocity is less than the mixture velocity.The qualitative effects of the local concentration and local fluid velocity on the particle velocity and slip velocity were investigated.The local fluid velocity contributes significantly to particle velocity and slip velocity,whereas the effect of the local concentration is marginal.A higher feeding concentration and mixture flow velocity result in an increased hydraulic gradient.The effect of the particle size gradation is slight,whereas the particle density plays a crucial role in the transport. 展开更多
关键词 deepsea mining vertical hydraulic transport experiment flow characteristics
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From the perspective of experimental practice: High-throughput computational screening in photocatalysis
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作者 Yunxuan Zhao Junyu Gao +2 位作者 Xuanang Bian Han Tang Tierui Zhang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期1-6,共6页
Photocatalysis,a critical strategy for harvesting sunlight to address energy demand and environmental concerns,is underpinned by the discovery of high-performance photocatalysts,thereby how to design photocatalysts is... Photocatalysis,a critical strategy for harvesting sunlight to address energy demand and environmental concerns,is underpinned by the discovery of high-performance photocatalysts,thereby how to design photocatalysts is now generating widespread interest in boosting the conversion effi-ciency of solar energy.In the past decade,computational technologies and theoretical simulations have led to a major leap in the development of high-throughput computational screening strategies for novel high-efficiency photocatalysts.In this viewpoint,we started with introducing the challenges of photocatalysis from the view of experimental practice,especially the inefficiency of the traditional“trial and error”method.Sub-sequently,a cross-sectional comparison between experimental and high-throughput computational screening for photocatalysis is presented and discussed in detail.On the basis of the current experimental progress in photocatalysis,we also exemplified the various challenges associated with high-throughput computational screening strategies.Finally,we offered a preferred high-throughput computational screening procedure for pho-tocatalysts from an experimental practice perspective(model construction and screening,standardized experiments,assessment and revision),with the aim of a better correlation of high-throughput simulations and experimental practices,motivating to search for better descriptors. 展开更多
关键词 PHOTOCATALYSIS High-throughput computational screening PHOTOCATALYST Theoretical simulations experiments
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Novel Method for Evaluating the Aging of Aviation Turbine Engine Oils via High-Temperature Bearing Deposit Tests
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作者 Hao Lichun Yang He +3 位作者 Song Haiqing Zhou Yunfan He Jingjian Liang Yuxiang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期67-77,共11页
Aviation turbine engine oils require excellent thermal-oxidative stability because of their high-temperature environments.High-temperature bearing deposit testing is a mandatory method for measuring the thermal-oxidat... Aviation turbine engine oils require excellent thermal-oxidative stability because of their high-temperature environments.High-temperature bearing deposit testing is a mandatory method for measuring the thermal-oxidative performance of aviation lubricant oils,and the relevant apparatus was improved in the present study.Two different commercial aviation turbine engine oils were tested,one with standard performance(known as the SL oil)and the other with high thermal stability,and their thermal-oxidative stability characteristics were evaluated.After 100 h of high-temperature bearing testing,the SL oil was analyzed by using various analytical techniques to investigate its thermal-oxidative process in the bearing test,with its thermal-oxidative degradation mechanism also being discussed.The results indicate that the developed high-temperature bearing apparatus easily meets the test requirements of method 3410.1 in standard FED-STD-791D.The viscosity and total acid number(TAN)of the SL oil increased with the bearing test time,and various deposits were produced in the bearing test,with the micro-particles of the carbon deposits being sphere-like,rod-like,and sheet-like in appearance.The antioxidant additives in the oil were consumed very rapidly in the first 30 h of the bearing test,with N-phenyl-1-naphthylamine being consumed faster than dioctyldiphenylamine.Overall,the oil thermal-oxidative process involves very complex physical and chemical mechanisms. 展开更多
关键词 aviation turbine engine oil high-temperature bearing deposit test thermal-oxidative degradation antioxidant additives
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Multi-environment BSA-seq using large F3 populations is able to achieve reliable QTL mapping with high power and resolution: An experimental demonstration in rice
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作者 Yan Zheng Ei Ei Khine +9 位作者 Khin Mar Thi Ei Ei Nyein Likun Huang Lihui Lin Xiaofang Xie Min Htay Wai Lin Khin Than Oo Myat Myat Moe San San Aye Weiren Wu 《The Crop Journal》 SCIE CSCD 2024年第2期549-557,共9页
Bulked-segregant analysis by deep sequencing(BSA-seq) is a widely used method for mapping QTL(quantitative trait loci) due to its simplicity, speed, cost-effectiveness, and efficiency. However, the ability of BSA-seq ... Bulked-segregant analysis by deep sequencing(BSA-seq) is a widely used method for mapping QTL(quantitative trait loci) due to its simplicity, speed, cost-effectiveness, and efficiency. However, the ability of BSA-seq to detect QTL is often limited by inappropriate experimental designs, as evidenced by numerous practical studies. Most BSA-seq studies have utilized small to medium-sized populations, with F2populations being the most common choice. Nevertheless, theoretical studies have shown that using a large population with an appropriate pool size can significantly enhance the power and resolution of QTL detection in BSA-seq, with F_(3)populations offering notable advantages over F2populations. To provide an experimental demonstration, we tested the power of BSA-seq to identify QTL controlling days from sowing to heading(DTH) in a 7200-plant rice F_(3)population in two environments, with a pool size of approximately 500. Each experiment identified 34 QTL, an order of magnitude greater than reported in most BSA-seq experiments, of which 23 were detected in both experiments, with 17 of these located near41 previously reported QTL and eight cloned genes known to control DTH in rice. These results indicate that QTL mapping by BSA-seq in large F_(3)populations and multi-environment experiments can achieve high power, resolution, and reliability. 展开更多
关键词 BSA-seq QTL mapping Large F3 population Multi-environment experiment Cross-validation
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High-performance and robust high-temperature polymer electrolyte membranes with moderate microphase separation by implementation of terphenyl-based polymers
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作者 Jinyuan Li Congrong Yang +3 位作者 Haojiang Lin Jicai Huang Suli Wang Gongquan Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期572-578,共7页
Acid loss and plasticization of phosphoric acid(PA)-doped high-temperature polymer electrolyte membranes(HT-PEMs)are critical limitations to their practical application in fuel cells.To overcome these barriers,poly(te... Acid loss and plasticization of phosphoric acid(PA)-doped high-temperature polymer electrolyte membranes(HT-PEMs)are critical limitations to their practical application in fuel cells.To overcome these barriers,poly(terphenyl piperidinium)s constructed from the m-and p-isomers of terphenyl were synthesized to regulate the microstructure of the membrane.Highly rigid p-terphenyl units prompt the formation of moderate PA aggregates,where the ion-pair interaction between piperidinium and biphosphate is reinforced,leading to a reduction in the plasticizing effect.As a result,there are trade-offs between the proton conductivity,mechanical strength,and PA retention of the membranes with varied m/p-isomer ratios.The designed PA-doped PTP-20m membrane exhibits superior ionic conductivity,good mechanical strength,and excellent PA retention over a wide range of temperature(80–160°C)as well as satisfactory resistance to harsh accelerated aging tests.As a result,the membrane presents a desirable combination of performance(1.462 W cm^(-2) under the H_(2)/O_(2)condition,which is 1.5 times higher than that of PBI-based membrane)and durability(300 h at 160°C and 0.2 A cm^(-2))in the fuel cell.The results of this study provide new insights that will guide molecular design from the perspective of microstructure to improve the performance and robustness of HT-PEMs. 展开更多
关键词 Fuel cell high-temperature polymer electrolyte membranes Microphase separation Poly(terphenyl piperidinium)s Phosphoric acid
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Unexpected Diversity in Ecosystem Nutrient Responses to Experimental Drought in Temperate Grasslands
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作者 Biying Qiu Niwu Te +8 位作者 Lin Song Yuan Shi Chuan Qiu Xiaoan Zuo Qiang Yu Jianqiang Qian Zhengwen Wang Honghui Wu Wentao Luo 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第4期831-841,共11页
The responses of ecosystem nitrogen (N) and phosphorus (P) to drought are an important component of globalchange studies. However, previous studies were more often based on site-specific experiments, introducing a sig... The responses of ecosystem nitrogen (N) and phosphorus (P) to drought are an important component of globalchange studies. However, previous studies were more often based on site-specific experiments, introducing a significantuncertainty to synthesis and site comparisons. We investigated the responses of vegetation and soil nutrientsto drought using a network experiment of temperate grasslands in Northern China. Drought treatment (66%reduction in growing season precipitation) was imposed by erecting rainout shelters, respectively, at the driest,intermediate, and wettest sites. We found that vegetation nutrient concentrations increased but soil nutrient concentrationsdecreased along the aridity gradient. Differential responses were observed under experimentaldrought among the three grassland sites. Specifically, the experimental drought did not change vegetation andsoil nutrient status at the driest site, while strongly reduced vegetation but increased soil nutrient concentrationsat the site with intermediate precipitation. On the contrary, experimental drought increased vegetation N concentrationsbut did not change vegetation P and soil nutrient concentrations at the wettest site. In general, the differentialeffects of drought on ecosystem nutrients were observed between manipulative and observationalexperiments as well as between sites. Our research findings suggest that conducting large-scale, consistent, andcontrolled network experiments is essential to accurately evaluate the effects of global climate change on terrestrialecosystem bio-geochemistry. 展开更多
关键词 Climate change drought experiment PRECIPITATION nutrient cycles
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Analysis of the Erosion-Corrosion Mechanism of the Air Cooler in a Hydrocracking Unit:A Numerical and Experimental Study
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作者 Su Guoqing Li Yan +1 位作者 Guo Hongli Zhang Jianwen 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期126-138,共13页
Corrosion leakages often occur in the air cooler of a hydrocracking unit,with the failure sites mainly located in the entrance area of the tubes.An analysis of the macroscopic morphology and corrosion products confirm... Corrosion leakages often occur in the air cooler of a hydrocracking unit,with the failure sites mainly located in the entrance area of the tubes.An analysis of the macroscopic morphology and corrosion products confirmed that the damage was caused by erosion-corrosion(E-C).Numerical and experimental methods were applied to investigate the E-C mechanism in the air cooler.Computational fluid dynamics(CFD)was used to calculate the hydrodynamic parameters of the air cooler.The results showed that there was a biased flow in the air cooler,which led to a significant increase in velocity,turbulent kinetic energy and wall shear within 0.2 m of the tube entrance.A visualization experiment was then performed to determine the principles of migration and transformation of multiphase flow in the air cooler tubes.Various flow patterns(pure droplet flow,mist flow,and annular flow)and their evolutionary processes were clearly depicted experimentally.The initiation mechanism and processes leading to the development of E-C in the air cooler were also determined.This study provided a comprehensive explanation for the E-C failures that occur in air coolers during operation. 展开更多
关键词 air cooler hydrocracking unit EROSION-CORROSION SIMULATION visualization experiment multiphase flow
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Visualization and characterization of experimental hydraulic fractures interacting with karst fracture-cavity distributions
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作者 Hanzhi Yang Xin Chang +4 位作者 Chunhe Yang Wuhao Guo Lei Wang Guokai Zhao Yintong Guo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1667-1683,共17页
Karst fracture-cavity carbonate reservoirs,in which natural cavities are connected by natural fractures to form cavity clusters in many circumstances,have become significant fields of oil and gas exploration and explo... Karst fracture-cavity carbonate reservoirs,in which natural cavities are connected by natural fractures to form cavity clusters in many circumstances,have become significant fields of oil and gas exploration and exploitation.Proppant fracturing is considered as the best method for exploiting carbonate reservoirs;however,previous studies primarily focused on the effects of individual types of geological formations,such as natural fractures or cavities,on fracture propagation.In this study,true-triaxial physical simulation experiments were systematically performed under four types of stress difference conditions after the accurate prefabrication of four types of different fracture-cavity distributions in artificial samples.Subsequently,the interaction mechanism between the hydraulic fractures and fracture-cavity structures was systematically analyzed in combination with the stress distribution,cross-sectional morphology of the main propagation path,and three-dimensional visualization of the overall fracture network.It was found that the propagation of hydraulic fractures near the cavity was inhibited by the stress concentration surrounding the cavity.In contrast,a natural fracture with a smaller approach angle(0°and 30°)around the cavity can alleviate the stress concentration and significantly facilitate the connection with the cavity.In addition,the hydraulic fracture crossed the natural fracture at the 45°approach angle and bypassed the cavity under higher stress difference conditions.A new stimulation effectiveness evaluation index was established based on the stimulated reservoir area(SRA),tortuosity of the hydraulic fractures(T),and connectivity index(CI)of the cavities.These findings provide new insights into the fracturing design of carbonate reservoirs. 展开更多
关键词 Karst fracture-cavity reservoir Fracturing experiment Fracture propagation Cross-sectional morphology Stimulation effectiveness
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Theoretical and experimental investigation of the resonance responses and chaotic dynamics of a bistable laminated composite shell in the dynamic snap-through mode
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作者 Meiqi WU Pengyu LV +3 位作者 Hongyuan LI Jiale YAN Huiling DUAN Wei ZHANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第4期581-602,共22页
The dynamic model of a bistable laminated composite shell simply supported by four corners is further developed to investigate the resonance responses and chaotic behaviors.The existence of the 1:1 resonance relations... The dynamic model of a bistable laminated composite shell simply supported by four corners is further developed to investigate the resonance responses and chaotic behaviors.The existence of the 1:1 resonance relationship between two order vibration modes of the system is verified.The resonance response of this class of bistable structures in the dynamic snap-through mode is investigated,and the four-dimensional(4D)nonlinear modulation equations are derived based on the 1:1 internal resonance relationship by means of the multiple scales method.The Hopf bifurcation and instability interval of the amplitude frequency and force amplitude curves are analyzed.The discussion focuses on investigating the effects of key parameters,e.g.,excitation amplitude,damping coefficient,and detuning parameters,on the resonance responses.The numerical simulations show that the foundation excitation and the degree of coupling between the vibration modes exert a substantial effect on the chaotic dynamics of the system.Furthermore,the significant motions under particular excitation conditions are visualized by bifurcation diagrams,time histories,phase portraits,three-dimensional(3D)phase portraits,and Poincare maps.Finally,the vibration experiment is carried out to study the amplitude frequency responses and bifurcation characteristics for the bistable laminated composite shell,yielding results that are qualitatively consistent with the theoretical results. 展开更多
关键词 bistable laminated composite shell dynamic snap-through mode Hopf bifurcation chaotic dynamics vibration experiment
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Integrated multi-scale approach combining global homogenization and local refinement for multi-field analysis of high-temperature superconducting composite magnets
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作者 Hanxiao GUO Peifeng GAO Xingzhe WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第5期747-762,共16页
Second-generation high-temperature superconducting(HTS)conductors,specifically rare earth-barium-copper-oxide(REBCO)coated conductor(CC)tapes,are promising candidates for high-energy and high-field superconducting app... Second-generation high-temperature superconducting(HTS)conductors,specifically rare earth-barium-copper-oxide(REBCO)coated conductor(CC)tapes,are promising candidates for high-energy and high-field superconducting applications.With respect to epoxy-impregnated REBCO composite magnets that comprise multilayer components,the thermomechanical characteristics of each component differ considerably under extremely low temperatures and strong electromagnetic fields.Traditional numerical models include homogenized orthotropic models,which simplify overall field calculation but miss detailed multi-physics aspects,and full refinement(FR)ones that are thorough but computationally demanding.Herein,we propose an extended multi-scale approach for analyzing the multi-field characteristics of an epoxy-impregnated composite magnet assembled by HTS pancake coils.This approach combines a global homogenization(GH)scheme based on the homogenized electromagnetic T-A model,a method for solving Maxwell's equations for superconducting materials based on the current vector potential T and the magnetic field vector potential A,and a homogenized orthotropic thermoelastic model to assess the electromagnetic and thermoelastic properties at the macroscopic scale.We then identify“dangerous regions”at the macroscopic scale and obtain finer details using a local refinement(LR)scheme to capture the responses of each component material in the HTS composite tapes at the mesoscopic scale.The results of the present GH-LR multi-scale approach agree well with those of the FR scheme and the experimental data in the literature,indicating that the present approach is accurate and efficient.The proposed GH-LR multi-scale approach can serve as a valuable tool for evaluating the risk of failure in large-scale HTS composite magnets. 展开更多
关键词 epoxy-impregnated high-temperature superconducting(HTS)magnet multi-scale method global homogenization(GH) local refinement(LR) multi-field analysis
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Experimental and simulation research on hollow AZ31 magnesium alloy three-channel joint by hot extrusion forming with sand mandrel
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作者 Shi Shengnan Wang Hongyu +4 位作者 Teng Fei Jiang Lei Sun Juncai Sun Jie Zhang Shunhu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期98-109,共12页
Magnesium alloy is one of the lightest metal structural materials.The weight is further reduced through the hollow structure.However,the hollow structure is easily damaged during processing.In order to maintain the ho... Magnesium alloy is one of the lightest metal structural materials.The weight is further reduced through the hollow structure.However,the hollow structure is easily damaged during processing.In order to maintain the hollow structure and to transfer the stresses during the high temperature deformation,the sand mandrel is proposed.In this paper,the hollow AZ31 magnesium alloy three-channel joint is studied by hot extrusion forming.Sand as one of solid granule medium is used to fill the hollow magnesium alloy.The extrusion temperatures are 230℃ and 300℃,respectively.The process parameters(die angle,temperature,bottom thickness,sidewall thickness,edge-to-middle ratio in bottom,bottom shape)of the hollow magnesium alloy are analyzed based on the results of experiments and the finite element method.The results are shown that the formability of the hollow magnesium alloy will be much better when the ratio of sidewall thickness to the bottom thickness is 1:1.5.Also when edge-to-middle ratio in bottom is about 1:1.5,a better forming product can be received.The best bottom shape in these experiments will be convex based on the forming results.The grain will be refined obviously after the extrusion.Also the microstructures will be shown as streamlines.And these lines will be well agreement with the mold in the corner. 展开更多
关键词 AZ31 magnesium alloy Three-channel joint SAND experiments and the finite element Die angle
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Study on the effect and mechanism of Swertia mussotii Franch. in the treatment of primary biliary cholangitis based on bioinformatics and in vitro experiments
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作者 Xing-Fang Zhang Meng-Meng Yang +6 位作者 Yi-Chen Guo Meng-Yuan Wang Hong-Xia Yang Ming Zhang Cen Li Li-Xin Wei Hong-Tao Bi 《Traditional Medicine Research》 2024年第3期32-42,共11页
Background:Primary biliary cholangitis(PBC)is a chronic biliary autoimmune liver disease characterized by intrahepatic cholestasis.Swertia mussotii Franch.(SMF)is a Tibetan medicine with hepatoprotective and anti-infl... Background:Primary biliary cholangitis(PBC)is a chronic biliary autoimmune liver disease characterized by intrahepatic cholestasis.Swertia mussotii Franch.(SMF)is a Tibetan medicine with hepatoprotective and anti-inflammatory activities.In this study,the therapeutic effect and potential mechanisms of SMF on PBC were investigated by bioinformatics analysis and in vitro experimental validation,with the aim of promoting the progress of SMF and PBC research.Methods:We first explored the therapeutic effects and key targets of SMF on PBC using a network pharmacology approach,further screened the core targets using the GSE79850 dataset,and finally validated the results using molecular docking techniques and in vitro experiments.Results:By bioinformatics analysis,we identified core targets of SMF for PBC treatment(STAT3,JAK2,TNF-α,and IL-1β)and important signaling pathways:JAK-STAT,TNF,and PI3K-AKT.The molecular docking results showed that the significant components of SMF had good binding properties to the core targets.In vitro experiments showed that SMF extracts improved the extent of epithelial-mesenchymal transition in human intrahepatic biliary epithelial cells and had a significant reversal effect on epithelial-mesenchymal transition process markers and potential targets in PBC.Conclusion:SMF may exert its therapeutic effects on PBC by acting on important targets such as STAT3,JAK2,TNF-α,IL-1β,Vimentin,and E-cadherin and the pathways in which they are involved. 展开更多
关键词 Swertia mussotii Franch. primary biliary cholangitis BIOINFORMATICS in vitro experiments
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Experimental and computational optimization of Prussian blue analogues as high-performance cathodes for sodium-ion batteries:A review
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作者 Gwangeon Oh Junghoon Kim +4 位作者 Shivam Kansara Hyokyeong Kang Hun-Gi Jung Yang-Kook Sun Jang-Yeon Hwang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期627-662,I0015,共37页
In this review,we discuss the electrochemical properties of Prussian blue(PB)for Na^(+)storage by combining structural engineering and electrolyte modifications.We integrated experimental data and density functional t... In this review,we discuss the electrochemical properties of Prussian blue(PB)for Na^(+)storage by combining structural engineering and electrolyte modifications.We integrated experimental data and density functional theory(DFT)in sodium-ion battery(SIB)research to refine the atomic arrangements and crystal lattices and introduce substitutions and dopants.These changes affect the lattice stability,intercalation,electronic and ionic conductivities,and electrochemical performance.We unraveled the intricate structure-electrochemical behavior relationship by combining experimental data with computational models,including first-principles calculations.This holistic approach identified techniques for optimizing PB and Prussian blue analog(PBA)structu ral properties for SIBs.We also discuss the tuning of electrolytes by systematically adjusting their composition,concentration,and additives using a combination of molecular dynamics(MD)simulations and DFT computations.Our review offers a comprehensive assessment of strategies for enhancing the electrochemical properties of PB and PBAs through structural engineering and electrolyte modifications,combining experimental insights with advanced computational simulations,and paving the way for next-generation energy storage systems. 展开更多
关键词 Prussian blue analogs(PBAs) Sodium ion batteries(SIBs) Structural engineering Electrolyte modifications experiments Density functional theory(DFT)
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Exploration on Teaching Reform of Medical Functional Experimental Science for International Students
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作者 Zhenzhen Liu 《Open Journal of Applied Sciences》 2024年第5期1185-1191,共7页
Medical Functional Experiment Science, a bridge between basic medicine and clinical medicine, integrates classical experimental teaching contents of three courses including physiology, pathophysiology and pharmacology... Medical Functional Experiment Science, a bridge between basic medicine and clinical medicine, integrates classical experimental teaching contents of three courses including physiology, pathophysiology and pharmacology. This course not only helps students to verify and reinforce theoretical knowledge, but also cultivates their capability of scientific thinking to discover and solve problems. Based on the characteristics of international students and current situation of the teaching platform in the laboratory at Yangtze University, this paper discusses a series of problems in the Medical Functional Experiment Science teaching for international students and puts forward some measures for teaching reform including optimizing experimental content, innovating experimental teaching methods and establishing effective experimental evaluation mode, in order to cultivate more international medical students with innovative ability. 展开更多
关键词 Medical Functional experiment Science Teaching Reform International Students
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