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Systematic experimental investigation on pressure build-up characteristics of water-jet injection into a molten LBE pool
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作者 Hao-Ran Huang Zi-Jian Deng +1 位作者 Song-Bai Cheng Jia-Yue Chen 《Nuclear Science and Techniques》 2025年第1期161-174,共14页
In the scenario of a steam generator tube rupture accident in a lead-cooled fast reactor,secondary circuit subcooled water under high pressure is injected into an ordinary-pressure primary vessel,where a molten lead-b... In the scenario of a steam generator tube rupture accident in a lead-cooled fast reactor,secondary circuit subcooled water under high pressure is injected into an ordinary-pressure primary vessel,where a molten lead-based alloy(typically pure lead or lead-bismuth eutectic(LBE))is used as the coolant.To clarify the pressure build-up characteristics under water-jet injection,this study conducted several experiments by injecting pressurized water into a molten LBE pool at Sun Yat-sen University.To obtain a further understanding,several new experimental parameters were adopted,including the melt temperature,water subcooling,injection pressure,injection duration,and nozzle diameter.Through detailed analyses,it was found that the pressure and temperature during the water-melt interaction exhibited a consistent variation trend with our previous water-droplet injection mode LBE experiment.Similarly,the existence of a steam explosion was confirmed,which typically results in a much stronger pressure build-up.For the non-explosion cases,increasing the injection pressure,melt-pool temperature,nozzle diameter,and water subcooling promoted pressure build-up in the melt pool.However,a limited enhancement effect was observed when increasing the injection duration,which may be owing to the continually rising pressure in the interaction vessel or the isolation effect of the generated steam cavity.Regardless of whether a steam explosion occurred,the calculated mechanical and kinetic energy conversion efficiencies of the melt were relatively small(not exceeding 4.1%and 0.7%,respectively).Moreover,the range of the conversion efficiency was similar to that of previous water-droplet experiments,although the upper limit of the jet mode was slightly lower. 展开更多
关键词 Lead-cooled fast reactor Steam generator tube rupture accident pressure build-up characteristics Experimental study pressure water-jet injection
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Novel high-temperature-resistant material SbLaO_(3) with superior hardness under high pressure
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作者 Haoqi Chen Haowen Jiang +5 位作者 Xuehui Jiang Jialin Wang Chengyao Zhang Defang Duan Jing Dong Yanbin Ma 《Chinese Physics B》 2025年第2期74-80,共7页
Perovskites have garnered significant attention in recent years. However, the presence of La atoms at the B-site in ABX_(3) structures has not yet been observed. Under high pressure, perovskites exhibit unexpected pha... Perovskites have garnered significant attention in recent years. However, the presence of La atoms at the B-site in ABX_(3) structures has not yet been observed. Under high pressure, perovskites exhibit unexpected phase transitions. In this study, we report the discovery of SbLaO_(3) under ambient pressure, with a space group of R3m. Mechanical property calculations indicate that it is a brittle material, and it possesses a band gap of 4.0266 e V, classifying it as an insulator.We also investigate the phase at 300 GPa, where the space group shifts to P2_(1/m). Additionally, the P2_(1/m) phase of LaInO_(3) under 300 GPa is explored. Ab initio molecular dynamics calculations reveal that the melting point of SbLaO_(3) is exceptionally high. The inclusion of Sb alters the electronic structure compared with LaInO_(3), and the Vickers hardness(H_(v)) is estimated to reach 20.97 GPa. This research provides insights into the phase transitions of perovskites under high pressure. 展开更多
关键词 high pressure molecular dynamics phase transition
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First-principles insights into the high-pressure stability and electronic characteristics of molybdenum nitride
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作者 Tao Wang Ming-Hong Wen +4 位作者 Xin-Xin Zhang Wei-Hua Wang Jia-Mei Liu Xu-Ying Wang Pei-Fang Li 《Chinese Physics B》 2025年第3期142-150,共9页
Molybdenum nitride,renowned for its exceptional physical and chemical properties,has garnered extensive attention and research interest.In this study,we employed first-principles calculations and the CALYPSO structure... Molybdenum nitride,renowned for its exceptional physical and chemical properties,has garnered extensive attention and research interest.In this study,we employed first-principles calculations and the CALYPSO structure prediction method to conduct a comprehensive analysis of the crystal structures and electronic properties of molybdenum nitride(Mo_(x)N_(1-x))under high pressure.We discovered two novel high-pressure phases:Imm2-MoN_(3) and Cmmm-MoN_(4),and confirmed their stability through the analysis of elastic constants and phonon dispersion curves.Notably,the MoN_(4) phase,with its high Vickers hardness of 36.9 GPa,demonstrates potential as a hard material.The results of this study have broadened the range of known high-pressure phases of molybdenum nitride,providing the groundwork for future theoretical and experimental researches. 展开更多
关键词 molybdenum nitride CALYPSO crystal structure high pressure
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Pressure and temperature effects resulting from impact onto materials of different reactivity
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作者 Andreas Heine Matthias Wickert 《Defence Technology(防务技术)》 2025年第2期221-230,共10页
The pressure and temperature increase resulting from the impact of different threats onto target materials is analyzed with a unified laboratory-scale setup.This allows deriving qualitative information on the occurrin... The pressure and temperature increase resulting from the impact of different threats onto target materials is analyzed with a unified laboratory-scale setup.This allows deriving qualitative information on the occurring phenomenology as well as quantitative statements about the relative effects sizes as a function of target material and threat.The considered target materials are steel,aluminum,and magnesium.As threats,kinetic energy penetrator,explosively formed projectile,and shaped charge jet are used.For the investigated combinations,the measured overpressures vary by a factor of up to 5 for a variation of the material,by a factor of up to 7 for a variation of the threat,and by a factor larger than 15for a simultaneous variation of both.The obtained results as well as the experimental approach are relevant for the basic understanding of impact effects and risks due to material reactivity.The paper combines two main aims.Firstly,to provide a summary of own prior work in a coherent journal article and,secondly,to review and discuss these earlier results with a new perspective. 展开更多
关键词 Impact effects pressure TEMPERATURE Risk assessment Material reactivity
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Exploring Lifshitz transition and superconductivity in 3R-NbS_(2) under pressure
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作者 Kun Chen Xindeng Lv +2 位作者 Simin Li Yanping Huang Tian Cui 《Chinese Physics B》 2025年第3期161-166,共6页
The interplay between electronic topological phase transitions and superconductivity in the field of condensed matter physics has consistently captivated researchers.Here we have succeeded in modulating the Lifshitz t... The interplay between electronic topological phase transitions and superconductivity in the field of condensed matter physics has consistently captivated researchers.Here we have succeeded in modulating the Lifshitz transition by pressure and realized superconductivity.At 25.7 GPa,superconductivity with a transition temperature of 1.9 K has been observed in 3R-NbS_(2).The Hall coefficient changes from negative to positive at 14 GPa,indicating a Lifshitz transition in 3R-NbS_(2),and the carrier concentration continues to increase with increasing pressure.X-ray diffraction results indicate that the appearance of superconductivity cannot be attributable to structural transitions.Based on theoretical calculations,the emergence of a new band is attributed to the Lifshitz transition and the new band coincides with the Fermi surface at the pressure of 30 GPa.These findings provide new insights into the relationship between the Lifshitz transition and superconductivity. 展开更多
关键词 high pressure SUPERCONDUCTIVITY Lifshitz transition 3R-NbS_(2)
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Experimental study on the buckling of composite cylinders with reinforced circular hole under hydrostatic pressure
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作者 Zhun Li Xinhu Zhang +3 位作者 Kechun Shen Jing Liu Jian Zhang Guang Pan 《Defence Technology(防务技术)》 2025年第2期231-247,共17页
In this paper,a type of reinforcing structure for composite shell with single and through hole is presented.The experimental tests for the composite shells without hole,with single hole and reinforced structure,with t... In this paper,a type of reinforcing structure for composite shell with single and through hole is presented.The experimental tests for the composite shells without hole,with single hole and reinforced structure,with through hole and reinforced structure subjected to hydrostatic pressure were carried out by the designed experimental test system.The mechanical responses of the composite shells under hydrostatic pressure are obtained by the high-speed camera and strain measurement.The results show that the entire deformation process of the shell can be divided into three:uniform compression,"buckling mode formation"and buckling.The"buckling mode formation"process is captured and reported for the first time.For the composite shell with single hole,the proposed reinforcing structure has a significant reinforcement effect on the shell and the buckling capacity of the shell is not weaker than the complete composite shell.For the composite shell with through hole,sealing effect can be achieved by the proposed reinforcing structure,but the buckling capacity of the shell after reinforcement can only reach 77%of the original buckling capacity. 展开更多
关键词 Composite cylindrical shell Circular hole Reinforcing structure BUCKLING Hydrostatic pressure
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Review of Underwater Anechoic Coating Technology Under Hydrostatic Pressure
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作者 Xinyu Jia Guoyong Jin Tiangui Ye 《哈尔滨工程大学学报(英文版)》 2025年第1期137-151,共15页
The underwater anechoic coating technology,which considers pressure resistance and low-frequency broadband sound absorption,has become a research hotspot in underwater acoustics and has received wide attention to addr... The underwater anechoic coating technology,which considers pressure resistance and low-frequency broadband sound absorption,has become a research hotspot in underwater acoustics and has received wide attention to address the increasingly advanced low-frequency sonar detection technology and adapt to the working environment of underwater vehicles in deep submergence.One the one hand,controlling low-frequency sound waves in water is more challenging than in air.On the other hand,in addition to initiating structural deformation,hydrostatic pressure also changes material parameters,both of which have a major effect on the sound absorption performance of the anechoic coating.Therefore,resolving the pressure resistance and acoustic performance of underwater acoustic coatings is difficult.Particularly,a bottleneck problem that must be addressed in this field is the acoustic structure design with low-frequency broadband sound absorption under high hydrostatic pressure.Based on the influence of hydrostatic pressure on underwater anechoic coatings,the research status of underwater acoustic structures under hydrostatic pressure from the aspects of sound absorption mechanisms,analysis methods,and structural designs is reviewed in this paper.Finally,the challenges and research trends encountered by underwater anechoic coating technology under hydrostatic pressure are summarized,providing a reference for the design and research of low-frequency broadband anechoic coating. 展开更多
关键词 Anechoic coatings Underwater acoustics Hydrostatic pressure Analysis methods Structural designs
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Formation mechanism of platinum nanoparticles prepared by atmospheric pressure plasma jet
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作者 Ying ZHAO Ali TAO +4 位作者 Zijing CHEN Yue RUAN Kunpeng WANG Ling ZHU Longwei CHEN 《Plasma Science and Technology》 2025年第3期104-110,共7页
An atmospheric pressure plasma jet(APPJ)approach is developed to prepare platinum nanoparticles(PtNPs)under mild reaction conditions of lower temperatures and without adding chemical reagents.Optical Emission Spectros... An atmospheric pressure plasma jet(APPJ)approach is developed to prepare platinum nanoparticles(PtNPs)under mild reaction conditions of lower temperatures and without adding chemical reagents.Optical Emission Spectroscopy(OES)and X-ray Photoelectron Spectroscopy(XPS)tests revealed that the APPJ contains a large number of high-energy active particles,which can generate solvated electrons in liquid thereby promoting the rapid reduction of Pt(Ⅳ)ions into Pt(0)atoms,and these atoms gradually grow into nanoparticles.After 3 min of treatment,PtNPs exhibit excellent dispersibility with a particle size distribution ranging from 1.8 to 2.8 nm.After 5 min,the particle size increases,and aggregation occurs.The zeta potentials for the two situations were-56.0 mV and-12.5 mV respectively.The results indicate that the treatment time has a significant impact on the dispersion,particle size distribution,and sol stability of the nanoparticles.Furthermore,it reveals the formation mechanism of PtNPs prepared by APPJ,which involves the generation and expansion of nanocrystalline nuclei,and the construction of negatively charged colloidal particles.The overall mechanism highlights the importance of the plasma-liquid interaction in the synthesis of PtNPs,offering a new perspective on the controllable production of nanomaterials using plasma technology. 展开更多
关键词 atmospheric pressure plasma jet platinum nanoparticles liquid-phase reduction formation mechanism
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Numerical studies of the voltage amplitude effect on plasma characteristics in atmospheric pressure driven by dual LF-RF frequency discharge
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作者 Yilin YU Zhibo ZHAO +2 位作者 Qiuyue NIE Shu CHEN Zhonglin ZHANG 《Plasma Science and Technology》 2025年第3期45-54,共10页
Dielectric barrier discharges(DBDs)are primarily utilized as efficient sources of large-volume diffuse plasmas.However,the synergistic interaction of certain key plasma factors limits their broader application.In the ... Dielectric barrier discharges(DBDs)are primarily utilized as efficient sources of large-volume diffuse plasmas.However,the synergistic interaction of certain key plasma factors limits their broader application.In the present paper,we report numerical investigations of the effects of voltage amplitude in dual-frequency excitation on atmospheric DBDs using a 50 kHz/5 MHz frequency combination.Our results indicate that varying the voltages for low frequency(LF)and radio frequency(RF)significantly influences the electron dynamics during discharge,resulting in distinct spatio-temporal distributions of electron and metastable particle densities.These findings contribute to the regulation of discharges under atmospheric pressure conditions and facilitate the attainment of non-equilibrium and nonlinear plasma parameters. 展开更多
关键词 dielectric barrier discharge atmospheric pressure plasma electron dynamics behavior
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Bond length and interface failure mechanism of anchor cable under continuous radial pressure conditions
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作者 Jian Ouyang Xiuzhi Shi +2 位作者 Xianyang Qiu Zongguo Zhang Zeyu Li 《International Journal of Mining Science and Technology》 2025年第2期231-247,共17页
The anchoring capacity of the anchor cable is closely related to the bonding length and radial pressure conditions.Through field pull-out tests,theoretical analysis,numerical simulation,and industrial tests,this study... The anchoring capacity of the anchor cable is closely related to the bonding length and radial pressure conditions.Through field pull-out tests,theoretical analysis,numerical simulation,and industrial tests,this study clarifies the relationship between radial pressure and bonding length for the ultimate pullout force and reveals the microscopic failure process of the resin-rock interface in the anchoring system.The results show that the ultimate load increases with the increase of bonding length in three different stages:rapid,slow,and uniform growth.The new mechanical model developed considering radial pressure describes the inverse relationship between radial pressure and the plastic zone on the bonding section,and quantifies the reinforcing effect of confining pressure on the anchoring force.During the pull-out process of the anchor cable,the generation of failure cracks is in the order of orifice,bottom,and middle of the hole.Radial pressure can effectively enhance the ultimate pull-out force,alleviate the oscillation increase of pull-out force,and inhibit resin cracking,but will produce an external crushing zone.It also reveals the synergistic effect between bonding length and radial pressure,and successfully carries out industrial tests of anchor cable support,which ensures the stability of the stope roof and provides an important reference for the design of anchor cable support in deep high-stress mines. 展开更多
关键词 Radial pressure Anchor cable Bond length Numerical simulation Interface failure Microscopic process
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Pressure-promoted ligand to metal energy transfer for emission enhancement of[Tb_(2)(BDC)_(3)(DMF)_(2)(H_(2)O)_(2)]_n metal-organic framework
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作者 Yunfeng Yang Kaiyan Yuan +3 位作者 Binhao Yang Qing Yang Yixuan Wang Xinyi Yang 《Chinese Physics B》 2025年第3期116-121,共6页
Lanthanide metal-organic frameworks(Ln-MOFs)have received extensive attention in the development of photoluminescent(PL)materials due to their stable structures and unique line-like emission spectroscopic properties.H... Lanthanide metal-organic frameworks(Ln-MOFs)have received extensive attention in the development of photoluminescent(PL)materials due to their stable structures and unique line-like emission spectroscopic properties.However,in order to prepare Ln-MOFs with high PL quantum yield(PLQY),further improving the sensitization efficiency of the“antenna effect”is essential.Herein,remarkably enhanced PL in[Tb_(2)(BDC)_(3)(DMF)_(2)(H_(2)O)_(2)]_n MOF is successfully achieved via high-pressure engineering at room temperature.Notably,the PL intensity continues to increase as the pressure increases,reaching its peak at 12.0 GPa,which is 4.4 times that of the initial state.Detailed experimental and theoretical calculations have demonstrated that pressure engineering significantly narrows the bandgap of[Tb_(2)(BDC)_(3)(DMF)_(2)(H_(2)O)_(2)]_n,optimizing both singlet and triplet energy levels.Ultimately,higher antenna effect sensitization efficiency is achieved by promoting intersystem crossing and energy transfer processes.Our work provides a promising strategy for the development of high PLQY Ln-MOFs. 展开更多
关键词 lanthanide metal-organic frameworks high pressure green light photoluminescence enhancement energy transfer
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Effects of Split Injection on Combustion,Emissions,and Intermediate Species of Natural Gas High-Pressure Direct Injection Engine
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作者 Lijiang Wei Xiuwei Lu +1 位作者 Wenqing Huang Qimin Song 《哈尔滨工程大学学报(英文版)》 2025年第1期210-223,共14页
Using natural gas(NG)as the primary fuel helps alleviate the fossil fuel crisis while reducing engine soot and nitrogen oxide(NO_(X))emissions.In this paper,the influences of a novel split injection concept on an NG h... Using natural gas(NG)as the primary fuel helps alleviate the fossil fuel crisis while reducing engine soot and nitrogen oxide(NO_(X))emissions.In this paper,the influences of a novel split injection concept on an NG high pressure direct injection(HPDI)engine are examined.Four typical split injection strategies,namely split pre-injection of pilot diesel(PD)and NG,split post-injection of PD and NG,split pre-injection of NG,and split post-injection of PD,were developed to investigate the influences on combustion and emissions.Results revealed that split pre injection of NG enhanced the atomization of PD,whereas the split post-injection of NG lowered the temperature in the core region of the PD spray,resulting in the deterioration of combustion.The effect of the split injection strategy on indicated thermal efficiency exceeded 7.5%.Split pre-injection was favorable to enhancing thermal efficiency,whereas split post-injection was not.Ignition delay,combustion duration,and premixed combustion time proportion were affected by injection strategies by 3.8%,50%,and 19.7%,respectively.Split pre-injection increased CH_(4) emission in the exhaust.Split post-injection,especially split post-injection of PD and NG,reduced the unburned CH_(4) emission by approximately 30%.When the split post-injection ratio was less than 30%,the trade-off between NO_(X) and soot was interrupted.The distribution range of hydroxyl radicals was expanded by pre-injection,and NO_(X) was generated in the region where the NG jet hit the wall.This paper provides valuable insights into the optimization of HPDI injection parameters. 展开更多
关键词 High pressure direct injection Natural gas Split injection strategy Injection ratio COMBUSTION
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A Flexible Smart Healthcare Platform Conjugated with Artificial Epidermis Assembled by Three‑Dimensionally Conductive MOF Network for Gas and Pressure Sensing
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作者 Qingqing Zhou Qihang Ding +8 位作者 Zixun Geng Chencheng Hu Long Yang Zitong Kan Biao Dong Miae Won Hongwei Song Lin Xu Jong Seung Kim 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期601-620,共20页
The rising flexible and intelligent electronics greatly facilitate the noninvasive and timely tracking of physiological information in telemedicine healthcare.Meticulously building bionic-sensitive moieties is vital f... The rising flexible and intelligent electronics greatly facilitate the noninvasive and timely tracking of physiological information in telemedicine healthcare.Meticulously building bionic-sensitive moieties is vital for designing efficient electronic skin with advanced cognitive functionalities to pluralistically capture external stimuli.However,realistic mimesis,both in the skin’s three-dimensional interlocked hierarchical structures and synchronous encoding multistimuli information capacities,remains a challenging yet vital need for simplifying the design of flexible logic circuits.Herein,we construct an artificial epidermal device by in situ growing Cu_(3)(HHTP)_(2) particles onto the hollow spherical Ti_(3)C_(2)T_(x) surface,aiming to concurrently emulate the spinous and granular layers of the skin’s epidermis.The bionic Ti_(3)C_(2)T_(x)@Cu_(3)(HHTP)_(2) exhibits independent NO_(2) and pressure response,as well as novel functionalities such as acoustic signature perception and Morse code-encrypted message communication.Ultimately,a wearable alarming system with a mobile application terminal is self-developed by integrating the bimodular senor into flexible printed circuits.This system can assess risk factors related with asthmatic,such as stimulation of external NO_(2) gas,abnormal expiratory behavior and exertion degrees of fingers,achieving a recognition accuracy of 97.6%as assisted by a machine learning algorithm.Our work provides a feasible routine to develop intelligent multifunctional healthcare equipment for burgeoning transformative telemedicine diagnosis. 展开更多
关键词 Ti_(3)C_(2)T_(x)@Cu_(3)(HHTP)_(2)composites NO_(2)/pressure flexible sensors Health-monitoring Machine learning
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Structural and transport properties of(Mg,Fe)SiO_(3) at high temperature and high pressure
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作者 Shu Huang Zhiyang Xiang +5 位作者 Shi He Luhan Yin Shihe Zhang Chen Chen Kaihua He Cheng Lu 《Chinese Physics B》 2025年第3期123-129,共7页
(Mg,Fe)SiO_(3) is primarily located in the mantle and has a substantial impact on geophysical and geochemical processes.Here,we employ molecular dynamics simulations to investigate the structural and transport propert... (Mg,Fe)SiO_(3) is primarily located in the mantle and has a substantial impact on geophysical and geochemical processes.Here,we employ molecular dynamics simulations to investigate the structural and transport properties of(Mg,Fe)SiO_(3) with varying iron contents at temperatures up to 5000 K and pressures up to 135 GPa.We thoroughly examine the effects of pressure,temperature,and iron content on the bond lengths,coordination numbers,viscosities,and electrical conductivities of(Mg,Fe)SiO_(3).Our calculations indicate that the increase of pressure leads to the shortening of the O-O and Mg-O bond lengths,while the Si-O bond lengths exhibit the initial increase with pressure up to 40 GPa,after which they are almost unchanged.The coordination numbers of Si transition from four-fold to six-fold and eventually reach eight-fold coordination at 135 GPa.The enhanced pressure causes the decrease of the diffusion coefficients and the increase of the viscosities of(Mg,Fe)SiO_(3).The increased temperatures slightly decrease the coordination numbers and viscosities,as well as obviously increase the diffusion coefficients and electrical conductivities of(Mg,Fe)SiO_(3).Additionally,iron doping facilitates the diffusion of Si and O,reduces the viscosities,and enhances the electrical conductivities of(Mg,Fe)SiO_(3).These findings advance fundamental understanding of the structural and transport properties of(Mg,Fe)SiO_(3) under high temperature and high pressure,which provide novel insights for unraveling the complexities of geological processes within the Earth's mantle. 展开更多
关键词 (Mg Fe)SiO_(3) structural and transport properties molecular dynamics simulations high temperature and high pressure
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Ti_(3)C_(2)T_(x) Composite Aerogels Enable Pressure Sensors for Dialect Speech Recognition Assisted by Deep Learning
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作者 Yanan Xiao He Li +8 位作者 Tianyi Gu Xiaoteng Jia Shixiang Sun Yong Liu Bin Wang He Tian Peng Sun Fangmeng Liu Geyu Lu 《Nano-Micro Letters》 2025年第5期1-15,共15页
Wearable pressure sensors capable of adhering comfortably to the skin hold great promise in sound detection.However,current intelligent speech assistants based on pressure sensors can only recognize standard languages... Wearable pressure sensors capable of adhering comfortably to the skin hold great promise in sound detection.However,current intelligent speech assistants based on pressure sensors can only recognize standard languages,which hampers effective communication for non-standard language people.Here,we prepare an ultralight Ti_(3)C_(2)T_(x)MXene/chitosan/polyvinylidene difluoride composite aerogel with a detection range of 6.25 Pa-1200 k Pa,rapid response/recovery time,and low hysteresis(13.69%).The wearable aerogel pressure sensor can detect speech information through the throat muscle vibrations without any interference,allowing for accurate recognition of six dialects(96.2%accuracy)and seven different words(96.6%accuracy)with the assistance of convolutional neural networks.This work represents a significant step forward in silent speech recognition for human–machine interaction and physiological signal monitoring. 展开更多
关键词 pressure sensor Wearable sensor Ti_(3)C_(2)T_(x) composite aerogel Dialect speech recognition
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Excess pore pressure behavior and evolution in deep coalbed methane reservoirs 被引量:1
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作者 Changqing Liu Zhaobiao Yang +3 位作者 Yong Qin Xia Yan Yunhai Wang Zhe Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第6期763-781,共19页
Deep coalbed methane(DCBM),an unconventional gas reservoir,has undergone significant advancements in recent years,sparking a growing interest in assessing pore pressure dynamics within these reservoirs.While some prod... Deep coalbed methane(DCBM),an unconventional gas reservoir,has undergone significant advancements in recent years,sparking a growing interest in assessing pore pressure dynamics within these reservoirs.While some production data analysis techniques have been adapted from conventional oil and gas wells,there remains a gap in the understanding of pore pressure generation and evolution,particularly in wells subjected to large-scale hydraulic fracturing.To address this gap,a novel technique called excess pore pressure analysis(EPPA)has been introduced to the coal seam gas industry for the first time to our knowledge,which employs dual-phase flow principles based on consolidation theory.This technique focuses on the generation and dissipation for excess pore-water pressure(EPWP)and excess pore-gas pressure(EPGP)in stimulated deep coal reservoirs.Equations have been developed respectively and numerical solutions have been provided using the finite element method(FEM).Application of this model to a representative field example reveals that excess pore pressure arises from rapid loading,with overburden weight transferred under undrained condition due to intense hydraulic fracturing,which significantly redistributes the weight-bearing role from the solid coal structure to the injected fluid and liberated gas within artificial pores over a brief timespan.Furthermore,field application indicates that the dissipation of EPWP and EPGP can be actually considered as the process of well production,where methane and water are extracted from deep coalbed methane wells,leading to consolidation for the artificial reservoirs.Moreover,history matching results demonstrate that the excess-pressure model established in this study provides a better explanation for the declining trends observed in both gas and water production curves,compared to conventional practices in coalbed methane reservoir engineering and petroleum engineering.This research not only enhances the understanding of DCBM reservoir behavior but also offers insights applicable to production analysis in other unconventional resources reliant on hydraulic fracturing. 展开更多
关键词 Deep coalbed methane CONSOLIDATION Excess pore-water pressure Excess pore-gas pressure Production data analysis
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Fracture geometry and breakdown pressure of radial borehole fracturing in multiple layers 被引量:1
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作者 Yu-Ning Yong Zhao-Quan Guo +3 位作者 Shou-Ceng Tian Lu-Yao Ma Tian-Yu Wang Mao Sheng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期430-444,共15页
Radial borehole fracturing that combines radial boreholes with hydraulic fracturing is anticipated to improve the output of tight oil and gas reservoirs.This paper aims to investigate fracture propagation and pressure... Radial borehole fracturing that combines radial boreholes with hydraulic fracturing is anticipated to improve the output of tight oil and gas reservoirs.This paper aims to investigate fracture propagation and pressure characteristics of radial borehole fracturing in multiple layers.A series of laboratory experiments with artificial rock samples(395 mm×395 mm×395 mm)was conducted using a true triaxial fracturing device.Three crucial factors corresponding to the vertical distance of adjacent radial borehole layers(vertical distance),the azimuth and diameter of the radial borehole are examined.Experimental results show that radial borehole fracturing in multiple layers generates diverse fracture geometries.Four types of fractures are identified based on the connectivity between hydraulic fractures and radial boreholes.The vertical distance significantly influences fracture propagation perpendicular to the radial borehole axis.An increase in the vertical distance impedes fracture connection across multiple radial borehole layers and reduces the fracture propagation distance along the radial borehole axis.The azimuth also influences fracture propagation along the radial borehole axis.Increasing the azimuth reduces the guiding ability of radial boreholes,which makes the fracture quickly curve to the maximum horizontal stress direction.The breakdown pressure correlates with diverse fracture geometries observed.When the fractures connect multi-layer radial boreholes,increasing the vertical distance decreases the breakdown pressure.Decreasing the azimuth and increasing the diameter also decrease the breakdown pressure.The extrusion force exists between the adjacent fractures generated in radial boreholes in multiple rows,which plays a crucial role in enhancing the guiding ability of radial boreholes and results in higher breakdown pressure.The research provides valuable theoretical insights for the field application of radial borehole fracturing technology in tight oil and gas reservoirs. 展开更多
关键词 Multi-layer radial boreholes Hydraulic fracturing Fracture propagation pressure characteristic
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An adaptive physics-informed deep learning method for pore pressure prediction using seismic data 被引量:3
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作者 Xin Zhang Yun-Hu Lu +2 位作者 Yan Jin Mian Chen Bo Zhou 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期885-902,共18页
Accurate prediction of formation pore pressure is essential to predict fluid flow and manage hydrocarbon production in petroleum engineering.Recent deep learning technique has been receiving more interest due to the g... Accurate prediction of formation pore pressure is essential to predict fluid flow and manage hydrocarbon production in petroleum engineering.Recent deep learning technique has been receiving more interest due to the great potential to deal with pore pressure prediction.However,most of the traditional deep learning models are less efficient to address generalization problems.To fill this technical gap,in this work,we developed a new adaptive physics-informed deep learning model with high generalization capability to predict pore pressure values directly from seismic data.Specifically,the new model,named CGP-NN,consists of a novel parametric features extraction approach(1DCPP),a stacked multilayer gated recurrent model(multilayer GRU),and an adaptive physics-informed loss function.Through machine training,the developed model can automatically select the optimal physical model to constrain the results for each pore pressure prediction.The CGP-NN model has the best generalization when the physicsrelated metricλ=0.5.A hybrid approach combining Eaton and Bowers methods is also proposed to build machine-learnable labels for solving the problem of few labels.To validate the developed model and methodology,a case study on a complex reservoir in Tarim Basin was further performed to demonstrate the high accuracy on the pore pressure prediction of new wells along with the strong generalization ability.The adaptive physics-informed deep learning approach presented here has potential application in the prediction of pore pressures coupled with multiple genesis mechanisms using seismic data. 展开更多
关键词 Pore pressure prediction Seismic data 1D convolution pyramid pooling Adaptive physics-informed loss function High generalization capability
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Emulsifying property,antioxidant activity,and bitterness of soybean protein isolate hydrolysate obtained by Corolase PP under high hydrostatic pressure 被引量:1
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作者 Haining Guan Chunmei Feng +3 位作者 Min Ren Xiaojun Xu Dengyong Liu Xiaoqin Diao 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1271-1278,共8页
Enzymatic hydrolysis of proteins can enhance their emulsifying properties and antioxidant activities.However,the problem related to the hydrolysis of proteins was the generation of the bitter taste.Recently,high hydro... Enzymatic hydrolysis of proteins can enhance their emulsifying properties and antioxidant activities.However,the problem related to the hydrolysis of proteins was the generation of the bitter taste.Recently,high hydrostatic pressure(HHP)treatment has attracted much interest and has been used in several studies on protein modification.Hence,the study aimed to investigate the effects of enzymatic hydrolysis by Corolase PP under different pressure treatments(0.1,100,200,and 300 MPa for 1-5 h at 50℃)on the emulsifying property,antioxidant activity,and bitterness of soybean protein isolate hydrolysate(SPIH).As observed,the hydrolysate obtained at 200 MPa for 4 h had the highest emulsifying activity index(47.49 m^(2)/g)and emulsifying stability index(92.98%),and it had higher antioxidant activities(44.77%DPPH free radical scavenging activity,31.12%superoxide anion radical scavenging activity,and 61.50%copper ion chelating activity).At the same time,the enhancement of emulsion stability was related to the increase of zeta potential and the decrease of mean particle size.In addition,the hydrolysate obtained at 200 MPa for 4 h had a lower bitterness value and showed better palatability.This study has a broad application prospect in developing food ingredients and healthy foods. 展开更多
关键词 Soybean protein isolate High hydrostatic pressure EMULSIFICATION ANTIOXIDANT Bitter taste
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Pressure stimulated current in progressive failure process of combined coal-rock under uniaxial compression:Response and mechanism 被引量:1
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作者 Tiancheng Shan Zhonghui Li +7 位作者 Xin Zhang Haishan Jia Xiaoran Wang Enyuan Wang Yue Niu Dong Chen Weichen Sun Dongming Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期227-243,共17页
Effective monitoring of the structural health of combined coal-rock under complex geological conditions by pressure stimulated currents(PSCs)has great potential for the understanding of dynamic disasters in undergroun... Effective monitoring of the structural health of combined coal-rock under complex geological conditions by pressure stimulated currents(PSCs)has great potential for the understanding of dynamic disasters in underground engineering.To reveal the effect of this way,the uniaxial compression experiments with PSC monitoring were conducted on three types of coal-rock combination samples with different strength combinations.The mechanism explanation of PSCs are investigated by resistivity test,atomic force microscopy(AFM)and computed tomography(CT)methods,and a PSC flow model based on progressive failure process is proposed.The influence of strength combinations on PSCs in the progressive failure process are emphasized.The results show the PSC responses between rock part,coal part and the two components are different,which are affected by multi-scale fracture characteristics and electrical properties.As the rock strength decreases,the progressive failure process changes obviously with the influence range of interface constraint effect decreasing,resulting in the different responses of PSC strength and direction in different parts to fracture behaviors.The PSC flow model is initially validated by the relationship between the accumulated charges of different parts.The results are expected to provide a new reference and method for mining design and roadway quality assessment. 展开更多
关键词 Combined coal-rock pressure stimulated current Progressive failure process MECHANISM Flow model
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