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Temperature rise of He Ⅱ forced flow and its negative Joule-Thomson effect
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作者 陈煜 巨永林 +2 位作者 郑青榕 鲁雪生 顾安忠 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第2期260-264,共5页
The temperature rise of He Ⅱ transfer system due to the negative Joule-Thomson(JT)effect is one of the major problems in the He Ⅱ forced flow system design.Negative Joule-Thomson effect of the He Ⅱ forced flow was ... The temperature rise of He Ⅱ transfer system due to the negative Joule-Thomson(JT)effect is one of the major problems in the He Ⅱ forced flow system design.Negative Joule-Thomson effect of the He Ⅱ forced flow was analyzed and calculated in this paper.The temperature rise due to the heat leak along the transfer pipeline was calculated by the simplified equation and was modified by considering the negative Joule-Thomson effect.The modified results were compared with the temperature rise obtained by non-linear differential equations with consideration of the pressure gradient.The results show that the pressure gradient has strong effect on the temperature distribution.The modified results are in good agreement with the values calculated by the complicated equation,which verifies the effectiveness of the simplified equation in calculating the temperature rise when the negative JT effect of He Ⅱ is known. 展开更多
关键词 He Joule-Thomson effect forced flow heat transfer numerical modeling
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A Method of Evaluating the Effectiveness of a Hydraulic Oscillator in Horizontal Wells
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作者 Zhen Zhong Yadong Li +1 位作者 Yuxuan Zhao Pengfei Ju 《Sound & Vibration》 EI 2023年第1期15-27,共13页
Bent-housing motor is the most widely used directional drilling tool,but it often encounters the problem of high friction when sliding drilling in horizontal wells.In this paper,a mathematical model is proposed to sim... Bent-housing motor is the most widely used directional drilling tool,but it often encounters the problem of high friction when sliding drilling in horizontal wells.In this paper,a mathematical model is proposed to simulate slide drilling with a friction reduction tool of axial vibration.A term called dynamic effective tractoring force(DETF)is defined and used to evaluate friction reduction effectiveness.The factors influencing the DETF are studied,and the tool placement optimization problem is investigated.The studyfinds that the drilling rate of penetration(ROP)can lower the DETF but does not change the trend of the DETF curve.To effectively work,the shock tool stiffness must be greater than some critical value.For the case study,the best oscillating frequency is within 15∼20 Hz.The reflection of the vibration at the bit boundary can intensify or weaken the friction reduction effec-tiveness,depending on the distance between the hydraulic oscillator and the bit.The optimal placement position corresponds to the plateau stage of the DETF curve.The reliability of the method is verified by thefield tests.The proposed method can provide a design and use guide to hydraulic oscillators and improve friction reduction effectiveness in horizontal wells. 展开更多
关键词 Hydraulic oscillator axial vibration friction reduction dynamic effective tractoring force placement optimization
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A Modeling Study of Effective Radiative Forcing and Climate Response Due to Tropospheric Ozone 被引量:13
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作者 Bing XIE Hua ZHANG +2 位作者 Zhili WANG Shuyun ZHAO Qiang FU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第7期819-828,共10页
This study simulates the effective radiative forcing (ERF) of tropospheric ozone from 1850 to 2013 and its effects on global climate using an aerosol-climate coupled model, BCC_AGCM2.0. I_CUACE/Aero, in combination ... This study simulates the effective radiative forcing (ERF) of tropospheric ozone from 1850 to 2013 and its effects on global climate using an aerosol-climate coupled model, BCC_AGCM2.0. I_CUACE/Aero, in combination with OMI (Ozone Monitoring Instrument) satellite ozone data. According to the OMI observations, the global annual mean tropospheric col- umn ozone (TCO) was 33.9 DU in 2013, and the largest TCO was distributed in the belts between 30°N and 45°N and at approximately 30°S; the annual mean TCO was higher in the Northern Hemisphere than that in the Southern Hemisphere; and in boreal summer and autumn, the global mean TCO was higher than in winter and spring. The simulated ERF due to the change in tropospheric ozone concentration from 1850 to 2013 was 0.46 W m-2, thereby causing an increase in the global annual mean surface temperature by 0.36°C, and precipitation by 0.02 mm d-1 (the increase of surface temperature had a significance level above 95%). The surface temperature was increased more obviously over the high latitudes in both hemispheres, with the maximum exceeding 1.4°C in Siberia. There were opposite changes in precipitation near the equator, with an increase of 0.5 mm d- 1 near the Hawaiian Islands and a decrease of about -0.6 mm d- 1 near the middle of the Indian Ocean. 展开更多
关键词 tropospheric ozone effective radiative forcing climate effect BCC_AGCM2.0. I_CUACE/Aero
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A modeling study of effective radiative forcing and climate response due to increased methane concentration 被引量:3
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作者 XIE Bing ZHANG Hua +1 位作者 YANG Dong-Dong WANG Zhi-Li 《Advances in Climate Change Research》 SCIE CSCD 2016年第4期241-246,共6页
An atmospheric general circulation model BCC_AGCM2.0 and observation data from ARIS were used to calculate the effective radiative forcing(ERF) due to increased methane concentration since pre-industrial times and i... An atmospheric general circulation model BCC_AGCM2.0 and observation data from ARIS were used to calculate the effective radiative forcing(ERF) due to increased methane concentration since pre-industrial times and its impacts on climate. The ERF of methane from 1750 to2011 was 0.46 W m^-2 by taking it as a well-mixed greenhouse gas, and the inhomogeneity of methane increased its ERF by about 0.02 W m^-2.The change of methane concentration since pre-industrial led to an increase of 0.31 ℃ in global mean surface air temperature and 0.02 mm d 1in global mean precipitation. The warming was prominent over the middle and high latitudes of the Northern Hemisphere(with a maximum increase exceeding 1.4℃). The precipitation notably increased(maximum increase of 1.8 mm d^-1) over the ocean between 10°N and 20° N and significantly decreased(maximum decrease 〉-0.6 mm d^-1) between 10° S and 10° N. These changes caused a northward movement of precipitation cell in the Intertropical Convergence Zone(ITCZ). Cloud cover significantly increased(by approximately 4%) in the high latitudes in both hemispheres, and sharply decreased(by approximately 3%) in tropical areas. 展开更多
关键词 METHANE effective radiative forcing Climate change
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Water blocking effect caused by the use of hydraulic methods for permeability enhancement in coal seams and methods for its removal 被引量:9
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作者 Liu Qian Guo Yusen +2 位作者 An Fenghua Lin Luyao Lai Yongming 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期615-621,共7页
To research techniques for removing the water blocking effect caused by hydraulic applications in coal seams,the use of surfactants is proposed,based on the mechanics of the water blocking effect.Centrifugal experimen... To research techniques for removing the water blocking effect caused by hydraulic applications in coal seams,the use of surfactants is proposed,based on the mechanics of the water blocking effect.Centrifugal experiments were used to validate the effects of using surfactants;the results show that after dealing with vacuum saturation with water,the volume of micropores decreases,which results in a larger average pore size,and the volume of transitional pores,mesopores,macropores and total pores increases.Based on the distribution of pore size,the operation mode of ‘‘water infusion after gas extraction,then continuing gas extraction" is recommended to improve the volume of coal mine gas drainage.When the reflectance of vitrinite in coal samples is less than 1,using the surfactants Fast T,1631,APG,BS can mitigate the damage caused by the water blocking effect.But when the reflectance of vitrinite is larger than 1.4,the damage caused by the water blocking effect can be increased.When the surfactant CMC is used in hydraulic applications,the capillary forces of coal samples are almost negative,which means the capillary force is in the same direction as the gas extraction.The direction of capillary forces benefits the gas flow.So,using CMC can play an active role in removing the water blocking effect.Centrifugal experiments confirm that using CMC can effectively remove the water blocking effect,which has a beneficial effect on improving the gas drainage volume. 展开更多
关键词 Gas extraction Hydraulic measures Water blocking effect Capillary force Surfactant
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Interference effects of two and three super-tall buildings under wind action 被引量:10
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作者 Ming Gu Zhuang-Ning Xie 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第5期687-696,共10页
Most previous investigations on interference effects of tall buildings under wind actions focused on the wind induced interference effects between two buildings,and the interference effects of three or more buildings ... Most previous investigations on interference effects of tall buildings under wind actions focused on the wind induced interference effects between two buildings,and the interference effects of three or more buildings have seldom been studied so far due to the huge workload involved in experiments and data processing.In this paper,mean and dynamic force/response interference effects and peak wind pressure interference effects of two and three tall buildings,especially the three-building configuration,are investigated through a series of wind tunnel tests on typical tall building models using high frequency force balance technique and wind pressure measurements.Furthermore,the present paper focuses on the effects of parameters,including breadth ratio and height ratio of the buildings and terrain category,on the interference factors and derives relevant regression results for the interference factors. 展开更多
关键词 Super-tall building · Wind force and response · Interference effect · Wind tunnel test
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Assessment of aerosol effective radiative forcing and surface air temperature response over eastern China in CMIP5 models 被引量:1
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作者 LIU Rui-Jin LIAO Hong 《Atmospheric and Oceanic Science Letters》 CSCD 2017年第3期228-234,共7页
The effective radiative forcing (ERF) and associated surface air temperature change over eastern China are estimated using multi-model results from CMIP5 (Coupled Model Intercomparison Project Phase 5). The model ... The effective radiative forcing (ERF) and associated surface air temperature change over eastern China are estimated using multi-model results from CMIP5 (Coupled Model Intercomparison Project Phase 5). The model results show that, relative to 1850, the multi-model and annual mean aerosol ERF for the year 2005 is -4.14 W m^-2 at the top of the atmosphere over eastern China (20°-45°N, 105°-122.5°E). As a result of this ERF, the multi-model and annual mean surface air temperature change in eastern China during 1850-2005 is -1.05℃, leading to a climate sensitivity of 0.24℃/ (Wm^-2) in this region. 展开更多
关键词 CMIPS aerosol effective radiative forcing surface air temperature change East Asia
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From Finite Nuclei to Neutron Stars: The Essential Role of High-Order Density Dependence in Effective Forces 被引量:1
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作者 Chong-Ji Jiang Yu Qiang +3 位作者 Da-Wei Guan Qing-Zhen Chai Chun-Yuan Qiao Jun-Chen Pei 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第5期11-15,共5页
A unified description of finite nuclei and equation of state of neutron stars presents both a major challenge and also opportunities for understanding nuclear interactions.Inspired by the Lee-Huang-Yang formula of har... A unified description of finite nuclei and equation of state of neutron stars presents both a major challenge and also opportunities for understanding nuclear interactions.Inspired by the Lee-Huang-Yang formula of hardsphere gases,we develop effective nuclear interactions with an additional high-order density dependent term.While the original Skyrme force SLy4 is widely used in studies of neutron stars,there are not satisfactory global descriptions of finite nuclei.The refitted SLy4' force can improve descriptions of finite nuclei but slightly reduces the radius of neutron star of 1.4 M_☉ with M_☉ being the solar mass.We find that the extended SLy4 force with a higher-order density dependence can properly describe properties of both finite nuclei and GW170817 binary neutron stars,including the mass-radius relation and the tidal deformability.This demonstrates the essential role of high-order density dependence at ultrahigh densities.Our work provides a unified and predictive model for neutron stars,as well as new insights for the future development of effective interactions. 展开更多
关键词 EOS The Essential Role of High-Order Density Dependence in effective Forces From Finite Nuclei to Neutron Stars NEUTRON
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The Shielding Effect of Multi-Pile Structures on Ice Force 被引量:1
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作者 史庆增 黄焱 宋安 《海洋工程:英文版》 EI 2004年第2期197-206,共10页
The shielding effect of the front pile-row on the ice force acting on the back pile-row is studied by ice force model tests. In the tests, the front pile-row is designed to model jacket legs and the back pile-row to m... The shielding effect of the front pile-row on the ice force acting on the back pile-row is studied by ice force model tests. In the tests, the front pile-row is designed to model jacket legs and the back pile-row to model the water resisting pipe-phalanx within the jacket. The shielding factor for ice force corresponding to different conditions are given in this paper. The research indicates that there are many factors, including the longitudinal and lateral spacing between the front and back pile-row, ice attacking angle and the ratio of pile diameter to ice thickness, that influence the shielding effect on ice force. 展开更多
关键词 ice force model test multi-pile structure shielding effect on ice force ice force shielding factor
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Derivation of energy-based base shear force coefficient considering hysteretic behavior and P-delta effects 被引量:2
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作者 Taner Ucar Onur Merter 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2018年第1期149-163,共15页
A modified energy-balance equation accounting for P-delta effects and hysteretic behavior of reinforced concrete members is derived. Reduced hysteretic properties of structural components due to combined stiffness and... A modified energy-balance equation accounting for P-delta effects and hysteretic behavior of reinforced concrete members is derived. Reduced hysteretic properties of structural components due to combined stiffness and strength degradation and pinching effects, and hysteretic damping are taken into account in a simple manner by utilizing plastic energy and seismic input energy modification factors. Having a pre-selected yield mechanism, energy balance of structure in inelastic range is considered. P-delta effects are included in derived equation by adding the external work of gravity loads to the work of equivalent inertia forces and equating the total external work to the modified plastic energy. Earthquake energy input to multi degree of freedom(MDOF) system is approximated by using the modal energy-decomposition. Energybased base shear coefficients are verified by means of both pushover analysis and nonlinear time history(NLTH) analysis of several RC frames having different number of stories. NLTH analyses of frames are performed by using the time histories of ten scaled ground motions compatible with elastic design acceleration spectrum and fulfilling duration/amplitude related requirements of Turkish Seismic Design Code. The observed correlation between energy-based base shear force coefficients and the average base shear force coefficients of NLTH analyses provides a reasonable confidence in estimation of nonlinear base shear force capacity of frames by using the derived equation. 展开更多
关键词 energy-based base shear force coefficient reduced hysteretic behavior P-delta effect pushover analysis nonlinear time history analysis
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A discussion on Corioli force effect and aftershock activity tendency of the M=8.1 Kunlun Mountain Pass earthquake on Nov. 14, 2001
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作者 吕坚 高建华 +2 位作者 刘吉夫 胡翠娥 黄双凤 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第4期459-467,共9页
Following the theory and definition of the Corioli force in physics, the Corioli force at the site of the M=8.1 Kunlun Mountain Pass earthquake on November 14, 2001, is examined in this paper on the basis of a statist... Following the theory and definition of the Corioli force in physics, the Corioli force at the site of the M=8.1 Kunlun Mountain Pass earthquake on November 14, 2001, is examined in this paper on the basis of a statistical research on relationship between the Corioli force effect and the maximum aftershock magnitude of 20 earthquakes with M7.5 in Chinese mainland, and then the variation tendency of aftershock activity of the M=8.1 earthquake is discussed. The result shows: a) Analyzing the Corioli force effect is an effective method to predict maximum aftershock magnitude of large earthquakes in Chinese mainland. For the sinistral slip fault and the reverse fault with its hanging wall moving toward the right side of the cross-focus meridian plane, their Corioli force pulls the two fault walls apart, decreasing frictional resistance on fault plane during the fault movement and releasing elastic energy of the mainshock fully, so the maximum magnitude of aftershocks would be low. For the dextral slip fault, its Corioli force presses the two walls against each other and increases the frictional resistance on fault plane, prohibiting energy release of the mainshock, so the maximum magnitude of aftershocks would be high. b) The fault of the M=8.1 Kunlun Mountain earthquake on Nov. 14, 2001 is essentially a sinistral strike-slip fault, and the Corioli force pulled the two fault walls apart. Magnitude of the induced stress is about 0.06 MPa. After a comparison analysis, we suggest that the aftershock activity level will not be high in the late period of this earthquake sequence, and the maximum magnitude of the whole aftershocks sequence is estimated to be about 6.0. 展开更多
关键词 Corioli force effect aftershock magnitude M=8.1 Kunlun Mountain Pass earthquake Chinese mainland
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The driving force effect of trade embodied carbon emissions and embodied SO_(2) emissions transferred in resources-rich areas: A case study of Shanxi province
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作者 WU Jing-hui 《Ecological Economy》 2021年第4期242-261,共20页
SDA (Structural Decomposition Analysis) model was applied to analyze the driving factors of embodied carbon and SO_(2) emissions transferred in Shanxi during 2007-2012 based on the input-output model from the perspect... SDA (Structural Decomposition Analysis) model was applied to analyze the driving factors of embodied carbon and SO_(2) emissions transferred in Shanxi during 2007-2012 based on the input-output model from the perspectives of region and industry.The results showed that the change of embodied carbon emissions and embodied SO_(2) emissions of Shanxi and other regions were hindered by the carbon (sulfur) emissions strength effect,but promoted by the intermediate (final) demand scale effect,the intermediate (final) structure effect and the input-output structure effect.The carbon emissions strength effect had a significant contribution to reducing the embodied carbon emissions transferred from industries in Shanxi to other regions.The intermediate (final) demand scale effect was the driving factor to increase the embodied carbon emissions transferred from industries in Shanxi to other regions.The sulfur emissions strength effect was the only factor that reduced the embodied SO_(2) emissions transferred from Shanxi to other industries.The change of embodied carbon emissions from industries in other regions to Shanxi was hindered by the carbon emissions strength effect,but the input-output structure effect and final demand scale effect both increased the embodied carbon emissions from industries in other regions to Shanxi.The change of the embodied SO_(2) emissions transferred from industries in other regions to Shanxi was inhibited by the sulfur emissions strength effect,but the input-output structure effect,the intermediate demand structure effect and the final demand scale effect were both the driving force effect of increasing the embodied SO_(2) emissions transferred from industries in other regions to Shanxi.The corresponding suggestions and measures were put forward. 展开更多
关键词 driving force effect embodied carbon emissions embodied SO_(2)emissions SDA model Shanxi province
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A glance on the effects of temperature on axisymmetric dynamic behavior of multiwall carbon nanotubes
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作者 S.T.Talebian M.Tahani +1 位作者 M.H.Abolbashari S.M.Hosseini 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第3期720-728,共9页
In this paper the effects of temperature on the radial breathing modes (RBMs) and radial wave propaga- tion in multiwall carbon nanotubes (MWCNTs) are inves- tigated using a continuum model of multiple elastic iso... In this paper the effects of temperature on the radial breathing modes (RBMs) and radial wave propaga- tion in multiwall carbon nanotubes (MWCNTs) are inves- tigated using a continuum model of multiple elastic isotropic shells. The van der Waals forces between tubes are simulated as a nonlinear function of interlayer spacing of MWCNTs. The governing equations are solved using a finite element method. A wide range of innermost radius-to-thickness ratio of MWCNTs is considered to enhance the investigation. The presented solution is verified by comparing the results with those reported in the literature. The effects of temperature on the van der Waals interaction coefficient between layers of MWCNTs are examined. It is found that the variation of the van der Waals interaction coefficient at high temperature is sensible. Subsequently, variations of RBM frequencies and radial wave propagation in MWCNTs with temperatures up to 1 600 K are illustrated. It is shown that the thick MWC- NTs are more sensible to temperature than the thin ones. 展开更多
关键词 Multiwall carbon nanotube Radial wave propa-gation. Radial breathing modes - van der Waals force. Ther-mal effects
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The Effect of Topographic Forcing on the Formation and Maintenance of Blocking
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作者 张佩 倪允琪 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第3期317-326,共10页
A barotropic channel model in β-plane is used to study the effect of topographic forcing on the formation and maintenance of blocking. The approximate analytical solution of potential vorticity equation can show the ... A barotropic channel model in β-plane is used to study the effect of topographic forcing on the formation and maintenance of blocking. The approximate analytical solution of potential vorticity equation can show the main property of the whole process of blocking. It is indicated that the topographic forcing is one of the main factors causing the blocking process. The results suggest that the nonlinear interaction plays a very important role in the stable 'Ω' situation of blocking. The atmospheric circulation with periodic and low-frequency oscillation, perhaps, is partly caused by topographic forcing. 展开更多
关键词 The effect of Topographic Forcing on the Formation and Maintenance of Blocking
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High-Fidelity Hugoniots of α Phase RDX Solid from High-Quality Force Field with Thermal,Zero-Point Vibration,and Anharmonic Effects
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作者 宋华杰 李华 +2 位作者 黄风雷 张树道 洪滔 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第8期30-34,共5页
It is shown that the introduction of thermal effect, zero-point vibration, and phonon anharmonicity to a high quality and first-principle-Sased force field (atomic potential) results in a significant improvement in ... It is shown that the introduction of thermal effect, zero-point vibration, and phonon anharmonicity to a high quality and first-principle-Sased force field (atomic potential) results in a significant improvement in predict- ing the densities for the α phase crystalline hexahydro-1,3,5-trinitro-l,3,5-triazine (RDX), and derivation of its high-fidelity Hugoniot locus and Mie-Grfineisen equation of state covering a very wide range of pressures and temperatures. This work can be used to efficiently and accurately predict the thermophysical properties of solid explosives over the pressures and temperatures to which they are subjected, which is a long-standing issue in the field of energetic materials. 展开更多
关键词 RDX High-Fidelity Hugoniots of Phase RDX Solid from High-Quality Force Field with Thermal Zero-Point Vibration and Anharmonic effects
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Analysis of influencing factors of excitation parameters for magnetoacoustic tomography with current injection 被引量:2
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作者 李粟 刘国强 +3 位作者 郭亮 张文伟 卢朝森 夏慧 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期496-503,共8页
Magneto-acoustic tomography with current injection(MAT-CI) is a type of hybrid imaging;under the excitation of the static magnetic field, the thermoacoustic effect and the Lorentz force effect will exist at the same t... Magneto-acoustic tomography with current injection(MAT-CI) is a type of hybrid imaging;under the excitation of the static magnetic field, the thermoacoustic effect and the Lorentz force effect will exist at the same time. Therefore,the detected signal is a mixed signal generated by the simultaneous action of the two effects, but the influence of excitation parameters on the two effects is different. In this paper, for objects with different conductivity, the proportion of thermoacoustic signal(TA) and magneto-acoustic signal(MA) in the mixed signal is quantitatively analyzed in terms of three aspects: the magnetic induction intensity, pulse excitation and injection current polarity. Experimental and simulation analyses show that the intensity ratio of MA to TA is not affected when the conductivity varies from 0.1 S/m to 1.5 S/m and other conditions remain unchanged. When the amplitude of the pulse excitation and the strength of the magnetic induction are different, the growth rates of MA and TA are different, which has a significant impact on the proportion of the two signals in the mixed signal. At the same time, due to the Lorentz force effect, MA is affected by the polarity of the injected current and the direction of the static magnetic field. The combination of the static magnetic field and the injected current can not only distinguish the two signals in the mixed signal, but also effectively enhance the intensity of the mixed signal and improve the quality of the reconstructed image. 展开更多
关键词 magneto-acoustic tomography with current injection(MAT-CI) thermoacoustic effect Lorentz force effect acoustic source
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Investigation of Eccentric PM on High-frequency Vibration in FSCW PM Machine Considering Force Modulation Effect
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作者 Jinghua Ji Weizhi Jiang +1 位作者 Wenxiang Zhao Tong Liu 《Chinese Journal of Electrical Engineering》 EI CSCD 2024年第2期59-69,共11页
This study investigates the negative influence of an eccentric permanent-magnet(PM)design on high-frequency electromagnetic vibration in fractional-slot concentrated-winding(FSCW)PM machines.First,an analytical expres... This study investigates the negative influence of an eccentric permanent-magnet(PM)design on high-frequency electromagnetic vibration in fractional-slot concentrated-winding(FSCW)PM machines.First,an analytical expression for the sideband current harmonics was derived using the double Fourier series expansion method.Then,the characteristics of the flux-density harmonics are studied from the perspective of the space-time distribution and initial phase relationship.The influence of the eccentric PM design on high-frequency electromagnetic and concentrated forces was studied based on the electromagnetic force modulation effect.Consequently,an eccentric PM design is not conducive to reducing the 2pth-order high-frequency electromagnetic forces.Finally,two FSCW PM machines with conventional and eccentric PM designs are manufactured and tested to verify the theoretical analysis.The results show that the eccentric PM design worsens high-frequency vibrations. 展开更多
关键词 Eccentric permanent magnet machine sideband current harmonics electromagnetic force modulation effect fractional-slot concentrated-winding high-frequency vibration
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Agglomeration rate and action forces between atomized particles of agglomerator and inhaled-particles from coal combustion 被引量:12
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作者 WEIFeng ZHANGJun-ying ZHENGChu-guang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期335-339,共5页
In order to remove efficiently haled-particles emissions from coal combustions, a new way was used to put forward the process of agglomeration and the atomization was produced by the nozzle and then sprayed into the ... In order to remove efficiently haled-particles emissions from coal combustions, a new way was used to put forward the process of agglomeration and the atomization was produced by the nozzle and then sprayed into the flue before precipitation devices of power station boiler in order to make inhaled-particles agglomerate into bigger particles, which can be easily removed but not change existing running conditions of boiler. According to this idea, a model is set up to study agglomeration rate and effect forces between fly ash inhaled-particles and atomized agglomerator particles. The developed agglomeration rate was expressed by relative particle number decreasing speed per unit volume. The result showed that viscosity force and flow resistance force give main influences on agglomeration effect of inhaled-particles, while springiness force and gravity have little effect on agglomeration effect of theirs. Factors influencing the agglomeration rate and effect forces are studied, including agglomerator concentration, agglomerator flux and agglomerator density, atomized-particles diameters and inhaled-particles diameter and so on. 展开更多
关键词 inhaled particles agglomerator effect forces agglomeration rate
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Mesoplasticity Approach to Studies of the Cutting Mechanism in Ultra-precision Machining 被引量:2
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作者 LEE WB Rongbin WANG Hao +2 位作者 TO Suet CHEUNG Chi Fai CHAN Chang Yuen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第2期219-228,共10页
There have been various theoretical attempts by researchers worldwide to link up different scales of plasticity studies from the nano-, micro- and macro-scale of observation, based on molecular dynamics, crystal plast... There have been various theoretical attempts by researchers worldwide to link up different scales of plasticity studies from the nano-, micro- and macro-scale of observation, based on molecular dynamics, crystal plasticity and continuum mechanics. Very few attempts, however, have been reported in ultra-precision machining studies. A mesoplasticity approach advocated by Lee and Yang is adopted by the authors and is successfully applied to studies of the micro-cutting mechanisms in ultra-precision machining. Traditionally, the shear angle in metal cutting, as well as the cutting force variation, can only be determined from cutting tests. In the pioneering work of the authors, the use of mesoplasticity theory enables prediction of the fluctuation of the shear angle and micro-cutting force, shear band formation, chip morphology in diamond turning and size effect in nano-indentation. These findings are verified by experiments. The mesoplasticity formulation opens up a new direction of studies to enable how the plastic behaviour of materials and their constitutive representations in deformation processing, such as machining can be predicted, assessed and deduced from the basic properties of the materials measurable at the microscale. 展开更多
关键词 ultra-precision machining cutting mechanism mesoplasticity shear angle prediction size effect micro-cutting force variation high frequency tool-tip vibration
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A Neo Explanation of the"Mass-Velocity Relation
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作者 Xu Shaozhi and Xu Xiangqun (Beijing Control Device Research Institute, P.O. Box 3913, Beijing 100854, P.R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1994年第2期68-71,共4页
A reinterpretation of the well-known formula of the 'mass-velocity relation' is exactlyderived from a new viewpoint with new concepts, such as the finiteness of the transmitting velocityof force (TVF), effecti... A reinterpretation of the well-known formula of the 'mass-velocity relation' is exactlyderived from a new viewpoint with new concepts, such as the finiteness of the transmitting velocityof force (TVF), effective action, and the coupled effect of the TVF for two EM fields, etc. Then, atrue meaning hidden in the Lorentz factor is exploited : i.e., when a charged particle is moving at aspeed v under an EM field, the effective action exerted on it by the field varies inversely with thespeed ratio β= v / U, where U is the TVF, which probably is equal to the propagation velocity ofEM field. The actual reduction of the effective action gives a false impression of mass gain.Accordingly, it is a major mistake in orientation to ascribe the (genuine) electrodynamics of movingbodies to any observation, or to any motion of an observer, while disregarding the facts of mutualaction. 展开更多
关键词 RELATIVITY Electrodynamics of moving bodies Mass-velocity relation Lorentz factor Transmitting velocity of force effective action Coupled effect.
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