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Generation of low-temperature plasma by pulse-width modulated signals and monitoring of the interaction thereof with the surface of objects
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作者 Tianbao MA Yauheni KALENKOVICH +1 位作者 Valeriy ROKACH Anatoly OSIPOV 《Plasma Science and Technology》 2025年第1期73-80,共8页
The article discusses the use of pulse-width modulation signals to generate low-temperature atmospheric plasma in an inert gas environment.The results of studies of the energy consumption of a low-temperature plasma g... The article discusses the use of pulse-width modulation signals to generate low-temperature atmospheric plasma in an inert gas environment.The results of studies of the energy consumption of a low-temperature plasma generation system depending on the duty rate,as well as the pulse repetition rate,are presented.The operating modes of the system have been established,in which a minimum of energy consumption is achieved.The issues of evaluating the interaction of plasma with objects based on the analysis of changes in signal parameters in the high-voltage circuit of the generator are also considered. 展开更多
关键词 low-temperature atmospheric pressure plasma parameters of plasma-exciting signals energy consumption reactive and apparent power plasma-object interaction
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Role of disturbance coefficient in monitoring and treatment of cerebral edema in patients with cerebral hemorrhage
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作者 Wen-Wen Gao Xiao-Bing Jiang +9 位作者 Peng Chen Liang Zhang Lei Yang Zhi-Hai Yuan Yao Wei Xiao-Qiang Li Xiao-Lu Tang Feng-Lu Wang Hao Wu Hai-Kang Zhao 《World Journal of Clinical Cases》 2025年第14期16-24,共9页
BACKGROUND At present,the conventional methods for diagnosing cerebral edema in clinical practice are computed tomography(CT)and magnetic resonance imaging(MRI),which can evaluate the location and degree of peripheral... BACKGROUND At present,the conventional methods for diagnosing cerebral edema in clinical practice are computed tomography(CT)and magnetic resonance imaging(MRI),which can evaluate the location and degree of peripheral cerebral edema,but cannot realize quantification.When patients have symptoms of diffuse cerebral edema or high cranial pressure,CT or MRI often suggests that cerebral edema is lagging and cannot be dynamically monitored in real time.Intracranial pressure monitoring is the gold standard,but it is an invasive operation with high cost and complications.For clinical purposes,the ideal cerebral edema monitoring should be non-invasive,real-time,bedside,and continuous dynamic monitoring.The dis-turbance coefficient(DC)was used in this study to dynamically monitor the occu-rrence,development,and evolution of cerebral edema in patients with cerebral hemorrhage in real time,and review head CT or MRI to evaluate the development of the disease and guide further treatment,so as to improve the prognosis of patients with cerebral hemorrhage.AIM To offer a promising new approach for non-invasive adjuvant therapy in cerebral edema treatment.METHODS A total of 160 patients with hypertensive cerebral hemorrhage admitted to the Department of Neurosurgery,Second Affiliated Hospital of Xi’an Medical University from September 2018 to September 2019 were recruited.The patients were randomly divided into a control group(n=80)and an experimental group(n=80).Patients in the control group received conventional empirical treatment,while those in the experimental group were treated with mannitol dehydration under the guidance of DC.Subsequently,we compared the two groups with regards to the total dosage of mannitol,the total course of treatment,the incidence of complications,and prognosis.RESULTS The mean daily consumption of mannitol,the total course of treatment,and the mean hospitalization days were 362.7±117.7 mL,14.8±5.2 days,and 29.4±7.9 in the control group and 283.1±93.6 mL,11.8±4.2 days,and 23.9±8.3 in the experimental group(P<0.05).In the control group,there were 20 patients with pulmonary infection(25%),30 with electrolyte disturbance(37.5%),20 with renal impairment(25%),and 16 with stress ulcer(20%).In the experimental group,pulmonary infection occurred in 18 patients(22.5%),electrolyte disturbance in 6(7.5%),renal impairment in 2(2.5%),and stress ulcers in 15(18.8%)(P<0.05).According to the Glasgow coma scale score 6 months after discharge,the prognosis of the control group was good in 20 patients(25%),fair in 26(32.5%),and poor in 34(42.5%);the prognosis of the experimental group was good in 32(40%),fair in 36(45%),and poor in 12(15%)(P<0.05).CONCLUSION Using DC for non-invasive dynamic monitoring of cerebral edema demonstrates considerable clinical potential.It reduces mannitol dosage,treatment duration,complication rates,and hospital stays,ultimately lowering hospital-ization costs.Additionally,it improves overall patient prognosis,offering a promising new approach for non-invasive adjuvant therapy in cerebral edema treatment. 展开更多
关键词 Noninvasive cerebral edema monitor Disturbance coefficient HYPERTENSION Cerebral hemorrhage Cerebral edema MANNITOL
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Role of variation coefficient of stone density in determining success of shock wave lithotripsy in urinary calculi
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作者 Nadeem Iqbal Aisha Hasan +2 位作者 Sajid Iqbal Sadaf Noureen Saeed Akhter 《World Journal of Nephrology》 2025年第1期110-118,共9页
BACKGROUND Various stone factors can affect the net results of shock wave lithotripsy(SWL).Recently a new factor called variation coefficient of stone density(VCSD)is being considered to have an impact on stone free r... BACKGROUND Various stone factors can affect the net results of shock wave lithotripsy(SWL).Recently a new factor called variation coefficient of stone density(VCSD)is being considered to have an impact on stone free rates.AIM To assess the role of VCSD in determining success of SWL in urinary calculi.METHODS Charts review was utilized for collection of data variables.The patients were subjected to SWL,using an electromagnetic lithotripter.Mean stone density(MSD),stone heterogeneity index(SHI),and VCSD were calculated by generating regions of interest on computed tomography(CT)images.Role of these factors were determined by applying the relevant statistical tests for continuous and categorical variables and a P value of<0.05 was gauged to be statistically significant.RESULTS There were a total of 407 patients included in the analysis.The mean age of the subjects in this study was 38.89±14.61 years.In total,165 out of the 407 patients could not achieve stone free status.The successful group had a significantly lower stone volume as compared to the unsuccessful group(P<0.0001).Skin to stone distance was not dissimilar among the two groups(P=0.47).MSD was significantly lower in the successful group(P<0.0001).SHI and VCSD were both significantly higher in the successful group(P<0.0001).CONCLUSION VCSD,a useful CT based parameter,can be utilized to gauge stone fragility and hence the prediction of SWL outcomes. 展开更多
关键词 Computed tomography Shock wave lithotripsy Stone heterogeneity Variation coefficient of stone density Kidney stones
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Structural Engineering of Anode Materials for Low-Temperature Lithium-Ion Batteries:Mechanisms,Strategies,and Prospects 被引量:3
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作者 Guan Wang Guixin Wang +2 位作者 Linfeng Fei Lina Zhao Haitao Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期169-195,共27页
The severe degradation of electrochemical performance for lithium-ion batteries(LIBs)at low temperatures poses a significant challenge to their practical applications.Consequently,extensive efforts have been contribut... The severe degradation of electrochemical performance for lithium-ion batteries(LIBs)at low temperatures poses a significant challenge to their practical applications.Consequently,extensive efforts have been contributed to explore novel anode materials with high electronic conductivity and rapid Li^(+)diffusion kinetics for achieving favorable low-temperature performance of LIBs.Herein,we try to review the recent reports on the synthesis and characterizations of low-temperature anode materials.First,we summarize the underlying mechanisms responsible for the performance degradation of anode materials at subzero temperatures.Second,detailed discussions concerning the key pathways(boosting electronic conductivity,enhancing Li^(+)diffusion kinetics,and inhibiting lithium dendrite)for improving the low-temperature performance of anode materials are presented.Third,several commonly used low-temperature anode materials are briefly introduced.Fourth,recent progress in the engineering of these low-temperature anode materials is summarized in terms of structural design,morphology control,surface&interface modifications,and multiphase materials.Finally,the challenges that remain to be solved in the field of low-temperature anode materials are discussed.This review was organized to offer valuable insights and guidance for next-generation LIBs with excellent low-temperature electrochemical performance. 展开更多
关键词 low-temperature performance Anode materials Microstructural regulations Surface modifications
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Influence of water coupling coefficient on the blasting effect of red sandstone specimens 被引量:2
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作者 Yang Li Renshu Yang +1 位作者 Yanbing Wang Dairui Fu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第1期148-166,共19页
This study investigates the impact of different water coupling coefficients on the blasting effect of red sandstone.The analysis is based on the theories of detonation wave and elastic wave,focusing on the variation i... This study investigates the impact of different water coupling coefficients on the blasting effect of red sandstone.The analysis is based on the theories of detonation wave and elastic wave,focusing on the variation in wall pressure of the blasting holes.Using DDNP explosive as the explosive load,blasting tests were conducted on red sandstone specimens with four different water coupling coefficients:1.20,1.33,1.50,and 2.00.The study examines the morphologies of the rock specimens after blasting under these different water coupling coefficients.Additionally,the fractal dimensions of the surface cracks resulting from the blasting were calculated to provide a quantitative evaluation of the extent of rock damage.CT scanning and 3D reconstruction were performed on the post-blasting specimens to visually depict the extent of damage and fractures within the rock.Additionally,the volume fractal dimension and damage degree of the post-blasting specimens are calculated.The findings are then combined with numerical simulation to facilitate auxiliary analysis.The results demonstrate that an increase in the water coupling coefficient leads to a reduction in the peak pressure on the hole wall and the crushing zone,enabling more of the explosion energy to be utilized for crack propagation following the explosion.The specimens exhibited distinct failure patterns,resulting in corresponding changes in fractal dimensions.The simulated pore wall pressure–time curve validated the derived theoretical results,whereas the stress cloud map and explosion energy-time curve demonstrated the buffering effect of the water medium.As the water coupling coefficient increases,the buffering effect of the water medium becomes increasingly prominent. 展开更多
关键词 Water coupling coefficient Radial uncoupled charge Numerical simulation Fractal dimension
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Low-temperature characteristicsof rubbers and performance testsof type 120 emergencyvalve diaphragms 被引量:1
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作者 Ming Gao Anhui Pan +5 位作者 Yi Huang Jiaqi Wang Yan Zhang Xiao Xie Huanre Han Yinghua Jia 《Railway Sciences》 2024年第1期47-58,共12页
Purpose–The type 120 emergency valve is an essential braking component of railway freight trains,butcorresponding diaphragms consisting of natural rubber(NR)and chloroprene rubber(CR)exhibit insufficientaging resista... Purpose–The type 120 emergency valve is an essential braking component of railway freight trains,butcorresponding diaphragms consisting of natural rubber(NR)and chloroprene rubber(CR)exhibit insufficientaging resistance and low-temperature resistance,respectively.In order to develop type 120 emergency valverubber diaphragms with long-life and high-performance,low-temperatureresistant CR and NR were processed.Design/methodology/approach–The physical properties of the low-temperature-resistant CR and NRwere tested by low-temperature stretching,dynamic mechanical analysis,differential scanning calorimetryand thermogravimetric analysis.Single-valve and single-vehicle tests of type 120 emergency valves werecarried out for emergency diaphragms consisting of NR and CR.Findings–The low-temperature-resistant CR and NR exhibited excellent physical properties.The elasticityand low-temperature resistance of NR were superior to those of CR,whereas the mechanical properties of thetwo rubbers were similar in the temperature range of 0℃–150℃.The NR and CR emergency diaphragms metthe requirements of the single-valve test.In the low-temperature single-vehicle test,only the low-temperaturesensitivity test of the NR emergency diaphragm met the requirements.Originality/value–The innovation of this study is that it provides valuable data and experience for futuredevelopment of type 120 valve rubber diaphragms. 展开更多
关键词 Natural rubber Chloroprene rubber low-temperature characteristic 120 emergency valve DIAPHRAGM
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Boosting oxygen reduction activity and CO_(2) resistance on bismuth ferrite-based perovskite cathode for low-temperature solid oxide fuel cells below 600℃ 被引量:1
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作者 Juntao Gao Zhiyun Wei +5 位作者 Mengke Yuan Zhe Wang Zhe Lü Qiang Li Lingling Xu Bo Wei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期600-609,I0013,共11页
Developing efficient and stable cathodes for low-temperature solid oxide fuel cells(LT-SOFCs) is of great importance for the practical commercialization.Herein,we propose a series of Sm-modified Bi_(0.7-x)Sm_xSr_(0.3)... Developing efficient and stable cathodes for low-temperature solid oxide fuel cells(LT-SOFCs) is of great importance for the practical commercialization.Herein,we propose a series of Sm-modified Bi_(0.7-x)Sm_xSr_(0.3)FeO_(3-δ) perovskites as highly-active catalysts for LT-SOFCs.Sm doping can significantly enhance the electrocata lytic activity and chemical stability of cathode.At 600℃,Bi_(0.675)Sm_(0.025)Sr_(0.3)FeO_(3-δ)(BSSF25) cathode has been found to be the optimum composition with a polarization resistance of 0.098 Ω cm^2,which is only around 22.8% of Bi_(0.7)Sr_(0.3)FeO_(3-δ)(BSF).A full cell utilizing BSSF25 displays an exceptional output density of 790 mW cm^(-2),which can operate continuously over100 h without obvious degradation.The remarkable electrochemical performance observed can be attributed to the improved O_(2) transport kinetics,superior surface oxygen adsorption capacity,as well as O_(2)p band centers in close proximity to the Fermi level.Moreover,larger average bonding energy(ABE) and the presence of highly acidic Bi,Sm,and Fe ions restrict the adsorption of CO_(2) on the cathode surface,resulting in excellent CO_(2) resistivity.This work provides valuable guidance for systematic design of efficient and durable catalysts for LT-SOFCs. 展开更多
关键词 low-temperature solid oxide fuel cell Perovskite cathode DFT calculations CO_(2) tolerance
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Enhancing performance of low-temperature processed CsPbI2Br all-inorganic perovskite solar cells using polyethylene oxide-modified TiO_(2) 被引量:1
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作者 Xu Zhao Naitao Gao +2 位作者 Shengcheng Wu Shaozhen Li Sujuan Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期786-794,共9页
CsPbX_(3)-based(X=I,Br,Cl)inorganic perovskite solar cells(PSCs)prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability.However,the high trap state d... CsPbX_(3)-based(X=I,Br,Cl)inorganic perovskite solar cells(PSCs)prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability.However,the high trap state density and serious charge recombination between low-temperature processed TiO_(2)film and inorganic perovskite layer interface seriously restrict the performance of all-inorganic PSCs.Here a thin polyethylene oxide(PEO)layer is employed to modify TiO_(2)film to passivate traps and promote carrier collection.The impacts of PEO layer on microstructure and photoelectric characteristics of TiO_(2)film and related devices are systematically studied.Characterization results suggest that PEO modification can reduce the surface roughness of TiO_(2)film,decrease its average surface potential,and passivate trap states.At optimal conditions,the champion efficiency of CsPbI_(2)Br PSCs with PEO-modified TiO_(2)(PEO-PSCs)has been improved to 11.24%from 9.03%of reference PSCs.Moreover,the hysteresis behavior and charge recombination have been suppressed in PEO-PSCs. 展开更多
关键词 polyethylene oxide-modified TiO_(2) film low-temperature process CsPbI_(2)Br-based all-inorganic perovskite solar cells photo-voltaic performance
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Advances in sodium-ion batteries at low-temperature: Challenges and strategies
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作者 Haoran Bai Xiaohui Zhu +3 位作者 Huaisheng Ao Guangyu He Hai Xiao Yinjuan Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期518-539,I0012,共23页
With the continuing boost in the demand for energy storage,there is an increasing requirement for batteries to be capable of operation in extreme environmental conditions.Sodium-ion batteries(SIBs) have emerged as a h... With the continuing boost in the demand for energy storage,there is an increasing requirement for batteries to be capable of operation in extreme environmental conditions.Sodium-ion batteries(SIBs) have emerged as a highly promising energy storage solution due to their promising performance over a wide range of temperatures and the abundance of sodium resources in the earth's crust.Compared to lithiumion batteries(LIBs),although sodium ions possess a larger ionic radius,they are more easily desolvated than lithium ions.Fu rthermore,SIBs have a smaller Stokes radius than lithium ions,resulting in improved sodium-ion mobility in the electrolyte.Nevertheless,SIBs demonstrate a significant decrease in performance at low temperatures(LT),which constrains their operation in harsh weather conditions.Despite the increasing interest in SIBs,there is a notable scarcity of research focusing specifically on their mechanism under LT conditions.This review explores recent research that considers the thermal tolerance of SIBs from an inner chemistry process perspective,spanning a wide temperature spectrum(-70 to100℃),particularly at LT conditions.In addition,the enhancement of electrochemical performance in LT SIBs is based on improvements in reaction kinetics and cycling stability achieved through the utilization of effective electrode materials and electrolyte components.Furthermore,the safety concerns associated with SIBs are addressed and effective strategies are proposed for mitigating these issues.Finally,prospects conducted to extend the environmental frontiers of commercial SIBs are discussed mainly from three viewpoints including innovations in materials,development and research of relevant theoretical mechanisms,and intelligent safety management system establishment for larger-scale energy storage SIBs. 展开更多
关键词 low-temperature Sodium-ion batteries Reaction kinetics Cycle stability Safety concerns of Sodium-ion batteries
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Temperature inversion enables superior stability for low-temperature Zn-ion batteries
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作者 Fu-Da Yu Zhe-Jian Yi +10 位作者 Rui-Yang Li Wei-Hao Lin Jie Chen Xiao-Yue Chen Yi-Ming Xie Ji-Huai Wu Zhang Lan Lan-Fang Que Bao-Sheng Liu Hao Luo Zhen-Bo Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期245-253,共9页
It is challenging for aqueous Zn-ion batteries(ZIBs)to achieve comparable low-temperature(low-T)performance due to the easy-frozen electrolyte and severe Zn dendrites.Herein,an aqueous electrolyte with a low freezing ... It is challenging for aqueous Zn-ion batteries(ZIBs)to achieve comparable low-temperature(low-T)performance due to the easy-frozen electrolyte and severe Zn dendrites.Herein,an aqueous electrolyte with a low freezing point and high ionic conductivity is proposed.Combined with molecular dynamics simulation and multi-scale interface analysis(time of flight secondary ion mass spectrometry threedimensional mapping and in-situ electrochemical impedance spectroscopy method),the temperature independence of the V_(2)O_(5)cathode and Zn anode is observed to be opposite.Surprisingly,dominated by the solvent structure of the designed electrolyte at low temperatures,vanadium dissolution/shuttle is significantly inhibited,and the zinc dendrites caused by this electrochemical crosstalk are greatly relieved,thus showing an abnormal temperature inversion effect.Through the disclosure and improvement of the above phenomena,the designed Zn||V_(2)O_(5)full cell delivers superior low-T performance,maintaining almost 99%capacity retention after 9500 cycles(working more than 2500 h)at-20°C.This work proposes a kind of electrolyte suitable for low-T ZIBs and reveals the inverse temperature dependence of the Zn anode,which might offer a novel perspective for the investigation of low-T aqueous battery systems. 展开更多
关键词 Aqueous Zn-ion batteries low-temperature performance Opposite temperature dependence Zndendrite growth Vanadium dissolution
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Modulating the Electrolyte Inner Solvation Structure via Low Polarity Co-solvent for Low-Temperature Aqueous Zinc-Ion Batteries
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作者 Yongchao Kang Feng Zhang +6 位作者 Houzhen Li Wangran Wei Huitong Dong Hao Chen Yuanhua Sang Hong Liu Shuhua Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第5期104-113,共10页
Aqueous zinc-ion batteries are regarded as the promising candidates for large-scale energy storage systems owing to low cost and high safety;however,their applications are restricted by their poor low-temperature perf... Aqueous zinc-ion batteries are regarded as the promising candidates for large-scale energy storage systems owing to low cost and high safety;however,their applications are restricted by their poor low-temperature performance.Herein,a low-temperature electrolyte for low-temperature aqueous zinc-ion batteries is designed by introducing low-polarity diglyme into an aqueous solution of Zn(ClO_(4))_(2).The diglyme disrupts the hydrogenbonding network of water and lowers the freezing point of the electrolyte to-105℃.The designed electrolyte achieves ionic conductivity up to16.18 mS cm^(-1)at-45℃.The diglyme and ClO_(4)^(-)reconfigure the solvated structure of Zn^(2+),which is more favorable for the desolvation of Zn^(2+)at low temperatures.In addition,the diglyme effectively suppresses the dendrites,hydrogen evolution reaction,and by-products of the zinc anode,improving the cycle stability of the battery.At-20℃,a Zn‖Zn symmetrical cell is cycled for 5200 h at 1 mA cm^(-2)and 1 mA h cm^(-2),and a Zn‖polyaniline battery achieves an ultra-long cycle life of 10000 times.This study sheds light on the future design of electrolytes with high ionic conductivity and easy desolvation at low temperatures for rechargeable batteries. 展开更多
关键词 aqueous zinc-ion batteries high performance inner solvation structure low polarity co-solvent low-temperature electrolyte
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Prediction of Coefficient of Restitution for Impact Elastoplastic Spheres Considering Finite Plate Thickness
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作者 Yunfeng Fan Hao Wang +3 位作者 Tao Zhou Limin Zou Zhinong Jiang Minghui Hu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第4期183-193,共11页
Collisions between objects are a relatively common phenomenon in nature.Analyses of collision processes can greatly contribute to solving problems such as impact-rub faults and particle impacts.The coefficient of rest... Collisions between objects are a relatively common phenomenon in nature.Analyses of collision processes can greatly contribute to solving problems such as impact-rub faults and particle impacts.The coefficient of restitution is a critical parameter in the analysis of collision processes.Many experiments have shown that the coefficient of restitution is closely related to the plate thickness,and the smaller the plate thickness,the more inaccurate the coefficient of restitution predicted by the existing model,which seriously affects the process of collision analysis.To remedy this shortcoming,this paper proposes a plate thickness influence factor with the ratio of sphere diameter to plate thickness as the variable.The plate thickness influence factor can optimize the coefficient of restitution model to effectively predict the coefficient of restitution of impacting elastoplastic spheres with finite plate thickness.Finally,the validity of the new model is verified using a large amount of experimental data. 展开更多
关键词 COLLISION coefficient of restitution Energy loss SPHERE
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ELLIPTIC EQUATIONS IN DIVERGENCE FORM WITH DISCONTINUOUS COEFFICIENTS IN DOMAINS WITH CORNERS
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作者 Jun CHEN Xuemei DENG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1903-1915,共13页
We study equations in divergence form with piecewise Cαcoefficients.The domains contain corners and the discontinuity surfaces are attached to the edges of the corners.We obtain piecewise C^(1,α) estimates across th... We study equations in divergence form with piecewise Cαcoefficients.The domains contain corners and the discontinuity surfaces are attached to the edges of the corners.We obtain piecewise C^(1,α) estimates across the discontinuity surfaces and provide an example to illustrate the issue regarding the regularity at the corners. 展开更多
关键词 elliptic equations divergence form discontinuous coefficients corner regularity
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Global stability coefficient of large underground caverns under static loading and earthquake wave condition
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作者 CHEN Peng-fei JIANG Quan +3 位作者 LIU Jian LI Shao-jun CHEN Tao HE Ben-guo 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2826-2843,共18页
Underground energy and resource development,deep underground energy storage and other projects involve the global stability of multiple interconnected cavern groups under internal and external dynamic disturbances.An ... Underground energy and resource development,deep underground energy storage and other projects involve the global stability of multiple interconnected cavern groups under internal and external dynamic disturbances.An evaluation method of the global stability coefficient of underground caverns based on static overload and dynamic overload was proposed.Firstly,the global failure criterion for caverns was defined based on its band connection of plastic-strain between multi-caverns.Then,overloading calculation of the boundary geostress and seismic intensity on the caverns model was carried out,and the critical unstable state of multi-caverns can be identified,if the plastic-strain band appeared between caverns during these overloading processes.Thus,the global stability coefficient for the multi-caverns under static loading and earthquake was obtained based on the corresponding overloading coefficient.Practical analysis for the Yingliangbao(YLB)hydraulic caverns indicated that this method can not only effectively obtain the global stability coefficient of caverns under static and dynamic earthquake conditions,but also identify the caverns’high-risk zone of local instability through localized plastic strain of surrounding rock.This study can provide some reference for the layout design and seismic optimization of underground cavern group. 展开更多
关键词 underground caverns global stability coefficient static-dynamic overload local instability
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Comparison of transport coefficients before and after density pump-out induced by resonant magnetic perturbation using a BOUT++ six-field model on the EAST tokamak
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作者 邓成成 刘子奚 +22 位作者 夏天阳 刘彦君 厉鹏程 龙飞飞 高翔 王守信 李国强 刘海庆 臧庆 李玖瑛 杨康宁 吴茗甫 尹晓宇 李弘 谢锦林 兰涛 毛文哲 刘阿娣 周楚 丁卫星 庄革 刘万东 the EAST Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第6期111-119,共9页
Many experiments have demonstrated that resonant magnetic perturbation(RMP) can affect the turbulent transport at the edge of the tokamak. Through the Experimental Advanced Superconducting Tokamak(EAST) density modula... Many experiments have demonstrated that resonant magnetic perturbation(RMP) can affect the turbulent transport at the edge of the tokamak. Through the Experimental Advanced Superconducting Tokamak(EAST) density modulation experiment, the particle transport coefficients were calculated using the experimental data, and the result shows that the particle transport coefficients increase with RMP. In this study, the six-field two-fluid model in BOUT++ is used to simulate the transport before and after density pump-out induced by RMP,respectively referred as the case without RMP and the case with RMP. In the linear simulations,the instabilities generally decreases for cases with RMP. In the nonlinear simulation, ELM only appears in the case without RMP. Additionally, the particle transport coefficient was analyzed,and the result shows that the particle transport coefficient becomes larger for the case with RMP,which is consistent with the experimental conclusion. Moreover, its magnitude is comparable to the results calculated from experimental data. 展开更多
关键词 BOUT++ resonant magnetic perturbation(RMP) transport coefficients
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Molecular Dynamics, Diffusion Coefficients and Activation Energy of the Electrolyte (Anode) in Lithium (Li and Li+), Sodium (Na and Na+) and Potassium (K and K+)
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作者 Alain Second Dzabana Honguelet Timothée Nsongo +1 位作者 Bitho Rodongo Earvin Loumbandzila 《Modeling and Numerical Simulation of Material Science》 2024年第1期39-57,共19页
This work is a simulation modelling with the LAMMPS calculation code of an electrode based on alkali metals (lithium, sodium and potassium) using the MEAM potential. For different multiplicities, two models were studi... This work is a simulation modelling with the LAMMPS calculation code of an electrode based on alkali metals (lithium, sodium and potassium) using the MEAM potential. For different multiplicities, two models were studied;with and without gap. In this work, we present the structural, physical and chemical properties of the lithium, sodium and potassium electrodes. For the structural properties, the cohesive energy and the mesh parameters were calculated, revealing that, whatever the chemical element selected, the compact hexagonal hcp structure is the most stable, followed by the face-centred cubic CFC structure, and finally the BCC structure. The most stable structure is lithium, with a cohesion energy of -6570 eV, and the lowest bcc-hcp transition energy of -0.553 eV/atom, followed by sodium. For physical properties, kinetic and potential energies were calculated for each of the sectioned chemical elements, with lithium achieving the highest value. Finally, for the chemical properties, we studied the diffusion coefficient and the activation energy. Only potassium followed an opposite order to the other two, with the quantities with lacunae being greater than those without lacunae, whatever the multiplicity. The order of magnitude of the diffusion coefficients is given by the relationship D<sub>Li</sub> > D<sub>Na</sub> > D<sub>k</sub> for the multiplicity 6*6*6, while for the activation energy the order is reversed. 展开更多
关键词 Molecular Dynamics Diffusion coefficients Activation Energy LITHIUM Alkali Metals MEAM Potential
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Particle residence time distribution and axial dispersion coefficient in a pressurized circulating fluidized bed by using multiphase particle-in-cell simulation
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作者 Jinnan Guo Daoyin Liu +2 位作者 Jiliang Ma Cai Liang Xiaoping Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期167-176,共10页
The particle residence time distribution(RTD)and axial dispersion coefficient are key parameters for the design and operation of a pressurized circulating fluidized bed(PCFB).In this study,the effects of pressure(0.1-... The particle residence time distribution(RTD)and axial dispersion coefficient are key parameters for the design and operation of a pressurized circulating fluidized bed(PCFB).In this study,the effects of pressure(0.1-0.6 MPa),fluidizing gas velocity(2-7 m·s^(-1)),and solid circulation rate(10-90 kg·m^(-2)·s^(-1))on particle RTD and axial dispersion coefficient in a PCFB are numerically investigated based on the multiphase particle-in-cell(MP-PIC)method.The details of the gas-solid flow behaviors of PCFB are revealed.Based on the gas-solid flow pattern,the particles tend to move more orderly under elevated pressures.With an increase in either fluidizing gas velocity or solid circulation rate,the mean residence time of particles decreases while the axial dispersion coefficient increases.With an increase in pressure,the core-annulus flow is strengthened,which leads to a wider shape of the particle RTD curve and a larger mean particle residence time.The back-mixing of particles increases with increasing pressure,resulting in an increase in the axial dispersion coefficient. 展开更多
关键词 Pressurized circulating fluidized bed MP-PIC method Residence time distribution Axial dispersion coefficient
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GCAGA: A Gini Coefficient-Based Optimization Strategy for Computation Offloading in Multi-User-Multi-Edge MEC System
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作者 Junqing Bai Qiuchao Dai Yingying Li 《Computers, Materials & Continua》 SCIE EI 2024年第6期5083-5103,共21页
To support the explosive growth of Information and Communications Technology(ICT),Mobile Edge Comput-ing(MEC)provides users with low latency and high bandwidth service by offloading computational tasks to the network... To support the explosive growth of Information and Communications Technology(ICT),Mobile Edge Comput-ing(MEC)provides users with low latency and high bandwidth service by offloading computational tasks to the network’s edge.However,resource-constrained mobile devices still suffer from a capacity mismatch when faced with latency-sensitive and compute-intensive emerging applications.To address the difficulty of running computationally intensive applications on resource-constrained clients,a model of the computation offloading problem in a network consisting of multiple mobile users and edge cloud servers is studied in this paper.Then a user benefit function EoU(Experience of Users)is proposed jointly considering energy consumption and time delay.The EoU maximization problem is decomposed into two steps,i.e.,resource allocation and offloading decision.The offloading decision is usually given by heuristic algorithms which are often faced with the challenge of slow convergence and poor stability.Thus,a combined offloading algorithm,i.e.,a Gini coefficient-based adaptive genetic algorithm(GCAGA),is proposed to alleviate the dilemma.The proposed algorithm optimizes the offloading decision by maximizing EoU and accelerates the convergence with the Gini coefficient.The simulation compares the proposed algorithm with the genetic algorithm(GA)and adaptive genetic algorithm(AGA).Experiment results show that the Gini coefficient and the adaptive heuristic operators can accelerate the convergence speed,and the proposed algorithm performs better in terms of convergence while obtaining higher EoU.The simulation code of the proposed algorithm is available:https://github.com/Grox888/Mobile_Edge_Computing/tree/GCAGA. 展开更多
关键词 Mobile edge computing multi-user-multi-edge joint optimization Gini coefficient adaptive genetic algorithm
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Impact of Low-temperature Storage on Volatile Flavor Compounds in Prepared Pork Products
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作者 Xiulian WANG Jiamin ZHANG +3 位作者 Ting BAI Wei WANG Kaihong YANG Lili JI 《Agricultural Biotechnology》 2024年第4期70-75,81,共7页
[Objectives]This study was conducted to explore the dynamic changes of volatile flavor compounds in prepared pork during storage at different low-temperature conditions.[Methods]Prepared pork was stored at 4,-4 and-18... [Objectives]This study was conducted to explore the dynamic changes of volatile flavor compounds in prepared pork during storage at different low-temperature conditions.[Methods]Prepared pork was stored at 4,-4 and-18℃.The volatile flavor compounds of prepared pork were determined by solid-phase microextraction-gas chromatography-mass spectrometry(SPME-GC-MS)at days 0,7,14,21 and 28,and relative odor activity value(OAV),principal component analysis(PCA)and cluster analysis(CA)were combined to analyze changes in volatile flavor compounds of prepared pork during storage.[Results]The total number of volatile flavor compounds gradually decreased with the prolongation of the storage period,and OAV analysis identified 22 key flavor compounds(OAV≥1).The results of PCA and CA showed that 2-methyl-1-butanol,1-octen-3-ol,linalool,cineole,hexanal and nonanal were the main key flavor components,and the degree of flavor degradation was low under both superchilling and freezing conditions.After 28 days of storage,the alcohol content in the chilling group was significantly higher than other two groups,and the overall content of volatile flavor compounds was also significantly higher than other two groups,indicating that the-4℃chilling storage was more favorable for maintaining the overall flavor of prepared pork.[Conclusions]This study provides a theoretical basis for finding a better storage method for prepared meat products. 展开更多
关键词 low-temperature storage Prepared pork Volatile flavor component Principal component analysis Cluster analysis
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The medium-temperature dependence of jet transport coefficient in high-energy nucleus-nucleus collisions
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作者 Man Xie Qing-Fei Han +2 位作者 En-Ke Wang Ben-Wei Zhang Han-Zhong Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第7期173-191,共19页
The medium-temperature T dependence of the jet transport coefficient̂q was studied via the nuclear modification factor RAA(p_(T))and elliptical flow parameter v_(2)(p_(T))for large transverse momentum p_(T) hadrons in... The medium-temperature T dependence of the jet transport coefficient̂q was studied via the nuclear modification factor RAA(p_(T))and elliptical flow parameter v_(2)(p_(T))for large transverse momentum p_(T) hadrons in high-energy nucleus-nucleus collisions.Within a next-to-leading-order perturbative QCD parton model for hard scatterings with modified fragmentation functions due to jet quenching controlled by q,we check the suppression and azimuthal anisotropy for large p_(T) hadrons,and extract q by global fits to RAA(pT)and v_(2)(pT)data in A+A collisions at RHIC and LHC,respectively.The numerical results from the best fits show that q∕T^(3) goes down with local medium-temperature T in the parton jet trajectory.Compared with the case of a constant q∕T^(3),the going-down T dependence of q∕T^(3) makes a hard parton jet to lose more energy near T_(c) and therefore strengthens the azimuthal anisotropy for large pT hadrons.As a result,v_(2)(p_(T))for large pT hadrons was enhanced by approximately 10%to better fit the data at RHIC/LHC.Considering the first-order phase transition from QGP to the hadron phase and the additional energy loss in the hadron phase,v_(2)(p_(T))is again enhanced by 5-10%at RHIC/LHC. 展开更多
关键词 Jet quenching Jet transport parameter Hadron suppression Elliptic flow coefficient Energy loss asymmetry
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