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Construction of 3D porous Cu_(1.81)S/nitrogen-doped carbon frameworks for ultrafast and long-cycle life sodium-ion storage
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作者 Chen Chen Hongyu Xue +6 位作者 Qilin Hu Mengfan Wang Pan Shang Ziyan Liu Tao Peng Deyang Zhang Yongsong Luo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期191-200,共10页
Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific capacities.However,the inferior intrinsic conductivity and large volume variation d... Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific capacities.However,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs anode.Herein,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for SIBs.Moreover,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 cycles.This work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode. 展开更多
关键词 copper sulfide nanoparticles porous carbon framework fast charging long-cycle performance sodium-ion full batteries
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Part 2: Review of Tokamak Physics as a Way to Construct a Device Optimal for Graviton Detection and Generation within a Confined Small Spatial Volume, as Opposed to Dyson’s “Infinite Astrophysical Volume” Calculations 被引量:2
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第1期138-155,共18页
Review of arguments in refutation of Dyson’s alleged prohibition against use of device physics as to determining if Gravitons can be determined to exist is followed up by use of a hot Plasma within a Tokamak in a red... Review of arguments in refutation of Dyson’s alleged prohibition against use of device physics as to determining if Gravitons can be determined to exist is followed up by use of a hot Plasma within a Tokamak in a redo of the amplitude of alleged Gravitational waves. This overlaps with gravitons, and we follow up with an analysis of the pertinent form of Gravitons, i.e. do we have massless or massive gravitons. In addition we also obtain GW of amplitude as low as five meters above the Tokamak center such low strain values are extremely close to brane world GW, and strain values in early universe cosmology. This is after our device analysis. Using Grischuk and Sachin (1975) amplitude for the GW generation due to plasma in a toroid, we generalize this result for Tokamak physics. We obtain evidence for strain values up to?in a Tokamak center. These values are an order of magnitude sufficient to allow for possible detection of gravitational waves. The critical breakthrough is in utilizing a burning plasma drift current, which relies upon a thermal contribution to an electric field. Such low strain values are extremely close to brane world GW, and strain values in early universe cosmology. We conclude with statements as to comparing our basic results with those of Yan-Gang Miao, Ying-Jie Zhao as to their generalized HUP which gives support to the suppositions given in our comparison of the character of gravitons which are initially at the start of inflation versus those of our present era, as measured by the Tokamak. 展开更多
关键词 TOKAMAK PHYSICS Confinement Time (of Plasma) GW Amplitude Drift Current
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In vivo label-free measurement of blood flow velocity symmetry based on dual line scanning third-harmonic generation microscopy excited at the 1700 nm window 被引量:1
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作者 Hui Cheng Jincheng Zhong +1 位作者 Ping Qiu Ke Wang 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第1期61-68,共8页
Measurement of bloodflow velocity is key to understanding physiology and pathology in vivo.While most measurements are performed at the middle of the blood vessel,little research has been done on characterizing the in... Measurement of bloodflow velocity is key to understanding physiology and pathology in vivo.While most measurements are performed at the middle of the blood vessel,little research has been done on characterizing the instantaneous bloodflow velocity distribution.This is mainly due to the lack of measurement technology with high spatial and temporal resolution.Here,we tackle this problem with our recently developed dual-wavelength line-scan third-harmonic generation(THG)imaging technology.Simultaneous acquisition of dual-wavelength THG line-scanning signals enables measurement of bloodflow velocities at two radially symmetric positions in both venules and arterioles in mouse brain in vivo.Our results clearly show that the instantaneous bloodflow velocity is not symmetric under general conditions. 展开更多
关键词 1700 nm-Window third-harmonic generation imaging blood flow velocity
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In vivo 3-photon fluorescence microscopy of white matter in mouse brain excited at the 1700 nm window 被引量:1
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作者 Jie Huang Jincheng Zhong +3 位作者 Shen Tong Yingxian Zhang Ping Qiu Ke Wang 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第5期81-87,共7页
White matter,a densely packed collection of myelinated axons,plays an essential part in neural networks.With high spatial resolution and deep penetration,multi-photon microscopy(MPM)is promising for white matter imagi... White matter,a densely packed collection of myelinated axons,plays an essential part in neural networks.With high spatial resolution and deep penetration,multi-photon microscopy(MPM)is promising for white matter imaging in animal models in vivo.The third harmonic generation(THG)signal can be generated from white matter,but the bottom part of the white matter layer generates weak THG due to its high scattering.Here,we demonstrate an in vivo labeling and imaging technology,capable of visualizing the white matter layer in the mouse brain,combining°uorescence labeling with MitoTracker Red and three-photon°uorescence(3PF)microscopy excited at the 1700 nm window.3PF signals are several times higher than THG signals,resulting in deeper imaging of the white matter layer with the former.Our results indicate that 3PF microscopy is a promising technology for white matter imaging in the deep brain in vivo. 展开更多
关键词 Three-photon microscopy white matter MYELIN MitoTracker Red
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Hierarchically Structured Nb_(2)O_5 Microflowers with Enhanced Capacity and Fast-Charging Capability for Flexible Planar Sodium Ion Micro-Supercapacitors 被引量:2
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作者 Jiaxin Ma Jieqiong Qin +8 位作者 Shuanghao Zheng Yinghua Fu Liping Chi Yaguang Li Cong Dong Bin Li Feifei Xing Haodong Shi Zhong‑Shuai Wu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期97-109,共13页
Planar Na ion micro-supercapacitors(NIMSCs) that offer both high energy density and power density are deemed to a promising class of miniaturized power sources for wearable and portable microelectron-ics. Nevertheless... Planar Na ion micro-supercapacitors(NIMSCs) that offer both high energy density and power density are deemed to a promising class of miniaturized power sources for wearable and portable microelectron-ics. Nevertheless, the development of NIMSCs are hugely impeded by the low capacity and sluggish Na ion kinetics in the negative electrode.Herein, we demonstrate a novel carbon-coated Nb_(2)O_5 microflower with a hierarchical structure composed of vertically intercrossed and porous nanosheets, boosting Na ion storage performance. The unique structural merits, including uniform carbon coating, ultrathin nanosheets and abun-dant pores, endow the Nb_(2)O_5 microflower with highly reversible Na ion storage capacity of 245 mAh g^(-1) at 0.25 C and excellent rate capability.Benefiting from high capacity and fast charging of Nb_(2)O_5 microflower, the planar NIMSCs consisted of Nb_(2)O_5 negative electrode and activated car-bon positive electrode deliver high areal energy density of 60.7 μWh cm^(-2),considerable voltage window of 3.5 V and extraordinary cyclability. Therefore, this work exploits a structural design strategy towards electrode materials for application in NIMSCs, holding great promise for flexible microelectronics. 展开更多
关键词 Nb_(2)O_5 nanosheets Microflowers Sodium ion micro-supercapacitors FLEXIBILITY Energy storage
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A dynamic database of solid-state electrolyte(DDSE)picturing all-solid-state batteries 被引量:1
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作者 Fangling Yang Egon Campos dos Santos +5 位作者 Xue Jia Ryuhei Sato Kazuaki Kisu Yusuke Hashimoto Shin-ichi Orimo Hao Li 《Nano Materials Science》 EI CAS CSCD 2024年第2期256-262,共7页
All-solid-state batteries(ASSBs)are a class of safer and higher-energy-density materials compared to conventional devices,from which solid-state electrolytes(SSEs)are their essential components.To date,investigations ... All-solid-state batteries(ASSBs)are a class of safer and higher-energy-density materials compared to conventional devices,from which solid-state electrolytes(SSEs)are their essential components.To date,investigations to search for high ion-conducting solid-state electrolytes have attracted broad concern.However,obtaining SSEs with high ionic conductivity is challenging due to the complex structural information and the less-explored structure-performance relationship.To provide a solution to these challenges,developing a database containing typical SSEs from available experimental reports would be a new avenue to understand the structureperformance relationships and find out new design guidelines for reasonable SSEs.Herein,a dynamic experimental database containing>600 materials was developed in a wide range of temperatures(132.40–1261.60 K),including mono-and divalent cations(e.g.,Li^(+),Na^(+),K^(+),Ag^(+),Ca^(2+),Mg^(2+),and Zn^(2+))and various types of anions(e.g.,halide,hydride,sulfide,and oxide).Data-mining was conducted to explore the relationships among different variates(e.g.,transport ion,composition,activation energy,and conductivity).Overall,we expect that this database can provide essential guidelines for the design and development of high-performance SSEs in ASSB applications.This database is dynamically updated,which can be accessed via our open-source online system. 展开更多
关键词 Solid-state electrolyte(SSE) All-solid-state battery(ASSB) Ionic conductivity Dynamic database Machine learning
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Pipeline thickness estimation using the dispersion of higher-order SH guided waves 被引量:1
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作者 代政辰 刘金霞 +3 位作者 龙云飞 张建海 Tribikram Kundu 崔志文 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期389-396,共8页
Thickness measurement plays an important role in the monitoring of pipeline corrosion damage. However, the requirement for prior knowledge of the shear wave velocity in the pipeline material for popular ultrasonic thi... Thickness measurement plays an important role in the monitoring of pipeline corrosion damage. However, the requirement for prior knowledge of the shear wave velocity in the pipeline material for popular ultrasonic thickness measurement limits its widespread application. This paper proposes a method that utilizes cylindrical shear horizontal(SH) guided waves to estimate pipeline thickness without prior knowledge of shear wave velocity. The inversion formulas are derived from the dispersion of higher-order modes with the high-frequency approximation. The waveform of the example problems is simulated using the real-axis integral method. The data points on the dispersion curves are processed in the frequency domain using the wave-number method. These extracted data are then substituted into the derived formulas. The results verify that employing higher-order SH guided waves for the evaluation of thickness and shear wave velocity yields less than1% error. This method can be applied to both metallic and non-metallic pipelines, thus opening new possibilities for health monitoring of pipeline structures. 展开更多
关键词 pipeline wall thickness higher-order modes SH guided waves DISPERSION
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Sequestration of helium and xenon via iron-halide compounds in early Earth 被引量:1
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作者 Jurong Zhang Hanyu Liu +1 位作者 Changfeng Chen Yanming Ma 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第3期83-88,共6页
The terrestrial abundance anomalies of helium and xenon suggest the presence of deep-Earth reservoirs of these elements,which has led to great interest in searching for materials that can host these usually unreactive... The terrestrial abundance anomalies of helium and xenon suggest the presence of deep-Earth reservoirs of these elements,which has led to great interest in searching for materials that can host these usually unreactive elements.Here,using an advanced crystal structure search approach in conjunction with first-principles calculations,we show that several Xe/He-bearing iron halides are thermodynamically stable in a broad region of P–T phase space below 60 GPa.Our results present a compelling case for sequestration of He and Xe in the early Earth and may suggest their much wider distribution in the present Earth than previously believed.These findings offer insights into key material-based and physical mechanisms for elucidating major geological phenomena. 展开更多
关键词 HALIDE SEARCHING INSIGHT
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Room Temperature Synthesis of Vertically Aligned Amorphous Ultrathin NiCo-LDH Nanosheets Bifunctional Flexible Supercapacitor Electrodes 被引量:1
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作者 Kwadwo Asare Owusu Zhaoyang Wang +7 位作者 Ali Saad Felix Ofori Boakye Muhammad Asim Mushtaq Muhammad Tahir Ghulam Yasin Dongqing Liu Zhengchun Peng Xingke Cai 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期277-286,共10页
Developing a simple scalable method to fabricate electrodes with high capacity and wide voltage range is desired for the real use of electrochemical supercapacitors.Herein,we synthesized amorphous NiCo-LDH nanosheets ... Developing a simple scalable method to fabricate electrodes with high capacity and wide voltage range is desired for the real use of electrochemical supercapacitors.Herein,we synthesized amorphous NiCo-LDH nanosheets vertically aligned on activated carbon cloth substrate,which was in situ transformed from Co-metal-organic framework materials nano-columns by a simple ion exchange process at room temperature.Due to the amorphous and vertically aligned ultrathin structure of NiCo-LDH,the NiCo-LDH/activated carbon cloth composites present high areal capacities of 3770 and 1480 mF cm^(-2)as cathode and anode at 2 mA cm^(-2),and 79.5%and 80%capacity have been preserved at 50 mA cm^(-2).In the meantime,they all showed excellent cycling performance with negligible change after>10000 cycles.By fabricating them into an asymmetric supercapacitor,the device achieves high energy densities(5.61 mWh cm^(-2)and 0.352 mW cm^(-3)).This work provides an innovative strategy for simplifying the design of supercapacitors as well as providing a new understanding of improving the rate capabilities/cycling stability of NiCo-LDH materials. 展开更多
关键词 amorphous nanosheets aqueous supercapacitor high volumetric/areal energy density NiCo-LDH room temperature synthesis
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Calculating <i>&delta;g<sub>tt</sub></i>at Boundary of Start of Planckian Physics Due to 1 Million Relic Black Holes
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第1期29-33,共5页
We use the ideas of a million black holes, at the boundary of contribution to the shift from Pre-Planckian to Planckian physics, as a summed up contribution from one million primordial black holes. I.e. this is assumi... We use the ideas of a million black holes, at the boundary of contribution to the shift from Pre-Planckian to Planckian physics, as a summed up contribution from one million primordial black holes. I.e. this is assuming a quantum bounce. This is an extension of work done by the author as to explain the nature of a transition from being tiny to when becomes 1 in value. Taking this into account, this article is a way to delineate the physics, inherent in the transition from to which puts a premium upon the growth of the inflaton, due to , with but with changing from , an 10255 increase in magnitude. This increase in magnitude may be the driver of subsequent inflation. When we have a pre quantum, especially if the inequality becomes an equality, and then the transition to marks the start of quantum gravity, whereas our black hole entropy model used to obtain a non zero entropy contribution from 1 million primordial relic black holes, as referenced, comes from Dr. Sen in an October 10 Run Run Shaw lecture in Stonybrook University. 展开更多
关键词 Massive Gravity INFLATON PHYSICS Infinite Quantum Statistics (Usual) Black Hole Entropy
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How a Laser Physics Induced Kerr-Newman Black Hole Can Release Gravitational Waves without Igniting the Black Hole Bomb (Explosion of a Mini Black Hole in a Laboratory)
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2018年第4期743-778,共36页
Note, that micro black holes last within micro seconds, and that we wish to ascertain how to build, in a laboratory, a black hole, which may exist say at least up to 10^?1 seconds and provide a test bed as to early un... Note, that micro black holes last within micro seconds, and that we wish to ascertain how to build, in a laboratory, a black hole, which may exist say at least up to 10^?1 seconds and provide a test bed as to early universe gravitational theories. First of all, it would be to determine, if the mini black hole bomb, would spontaneously occur, unless the Kerr-Newmann black hole were carefully engineered in the laboratory. Specifically, we state that this paper is modeling the creation of an actual Kerr Newman black hole via laser physics, or possibly by other means. We initiate a model of an induced Kerr-Newman black Holes, with specific angular momentum J, and then from there model was to what would happen as to an effective charge, Q, creating an E and B field, commensurate with the release of GWs. The idea is that using a frame of reference trick, plus E + i B = ?function of the derivative of a complex valued scalar field, as given by Appell, in 1887, and reviewed by Whittaker and Watson, 1927 of their “A Course of Modern Analysis” tome that a first principle identification of a B field, commensurate with increase of thermal temperature, T, so as to have artificially induced GW production. This is compared in part with the Park 1955 paper of a spinning rod, producing GW, with the proviso that both the spinning rod paper, and this artificial Kerr-Newman Black hole will employ the idea of lasers in implementation of their respective GW radiation. The idea is in part partly similar to an idea the author discussed with Dr. Robert Baker, in 2016 with the difference that a B field would be generated and linked to effects linked with induced spin to the Kerr-Newman Black hole. We close with some observations about the “black holes have no hair” theorem, and our problem. Citing some recent suppositions that this “theorem” may not be completely true and how that may relate to our experimental situation. We close with observations from Haijicek, 2008 as which may be pertinent to Quantization of Gravity. Furthermore as an answer to questions raised by a referee, we will have a final statement as to how this problem is for a real black hole being induced, and answering his questions in his review, which will be included in a final appendix to this paper. The main issue which is now to avoid the black hole bomb effect which would entail an explosion of a small black hole in a laboratory. Furthermore as an answer to questions raised by a referee, we will have a final statement as to how this problem is for a real black hole being induced, and answering his questions in his review, which will be included in a final appendix to this paper. In all, the main end result is to try to avoid the so called black hole bomb effect, where a mini black hole would explode in a laboratory setting within say 10^?16 or so seconds, i.e. the idea would be to have a reasonably stable configuration within put laser energy, but a small mass, and to do it over hopefully 10^15 or more times longer than the 10^?16 seconds where the mini black hole would quickly evaporate. I.e. a duration of say up to 10^?1 seconds which would provide a base line as to astrophysical modeling of a Kerr-Newman black hole. 展开更多
关键词 KERR NEWMAN Black Hole High-Frequency Gravitational Waves (HGW) CAUSAL DISCONTINUITY
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Examination of Minimum Time Step, from Modified Heisenberg Uncertainty Principle, Inflaton Physics and Black Hole Physics
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第1期39-45,共7页
First, we calculate the minimum length for the creation of a 1045 Hz relic Gravitational wave. Next, we look Padamababhan’s inflaton physics, and work done by the author for a modified Heisenberg Uncertainty principl... First, we calculate the minimum length for the creation of a 1045 Hz relic Gravitational wave. Next, we look Padamababhan’s inflaton physics, and work done by the author for a modified Heisenberg Uncertainty principle for constraints on a minimum time step. Sciama’s work in “Black hole explosions” (1982) gives us a linkage between a decay rate for black holes, in terms of a life time, and the mass, M of the black hole, which when combined with a simple exposition from Susskind and Hrabovsky (2013) for the most basic evolution the time change in energy E(t), which is how we form a first order treatment of the square of a minimum time step . We then reference what was done by Ng (2008) as far as infinite quantum statistics, for entropy as a particle count, and from first principle get constraints upon entropy production, as a function of boundaries on minimum time step. We assume massive Gravity, and obtain a peak 1036 Giga Hertz frequency range (1045 Hertz) for relic Gravitational waves, and Gravitons. 展开更多
关键词 MASSIVE GRAVITY INFLATON PHYSICS INFINITE Quantum Statistics MODIFIED Poisson’s Equation
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Estimation of peak wave period from surface texture motion in videos
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作者 Haipeng Yu Xiaoliang Chu Guang Yuan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第9期136-144,共9页
Wave information retrieval from videos captured by a single camera has been increasingly applied in marine observation.However,when the camera observes ocean waves at low grazing angles,the accurate extraction of wave... Wave information retrieval from videos captured by a single camera has been increasingly applied in marine observation.However,when the camera observes ocean waves at low grazing angles,the accurate extraction of wave information from videos will be affected by the interference of the fine ripples on the sea surface.To solve this problem,this study develops a method for estimating peak wave periods from videos captured at low grazing angles.The method extracts the motion of the sea surface texture from the video and obtains the peak wave period via the spectral analysis.The calculation results captured from real-world videos are compared with those obtained from X-band radar inversion and tracking buoy movement,with maximum deviations of 8%and 14%,respectively.The analysis of the results shows that the peak wave period of the method has good stability.In addition,this paper uses a pinhole camera model to convert the displacement of the texture from pixel height to actual height and performs moving average filtering on the displacement of the texture,thus conducting a preliminary exploration of the inversion of significant wave height.This study helps to extend the application of sea surface videos. 展开更多
关键词 low grazing angle sea surface texture VIDEO peak wave period significant wave height image matching
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Effects of confining pressure and pore pressure on multipole borehole acoustic field in fluid-saturated porous media
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作者 赵志强 刘金霞 +1 位作者 刘建宇 崔志文 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期468-476,共9页
In-situ stress is a common stress in the exploration and development of oil reservoirs. Therefore, it is of great significance to study the propagation characteristics of borehole acoustic waves in fluid-saturated por... In-situ stress is a common stress in the exploration and development of oil reservoirs. Therefore, it is of great significance to study the propagation characteristics of borehole acoustic waves in fluid-saturated porous media under stress.Based on the acoustoelastic theory of fluid-saturated porous media, the field equation of fluid-saturated porous media under the conditions of confining pressure and pore pressure and the acoustic field formula of multipole source excitation in open hole are given. The influences of pore pressure and confining pressure on guided waves of multipole borehole acoustic field in fluid-saturated porous media are investigated. The numerical results show that the phase velocity and excitation intensity of guided wave increase significantly under the confining pressure. For a given confining pressure, the phase velocity of the guided wave decreases with pore pressure increasing. The excitation intensity of guided wave increases at low frequency and then decreases at high frequency with pore pressure increasing, except for that of Stoneley wave which decreases in the whole frequency range. These results will help us get an insight into the influences of confining pressure and pore pressure on the acoustic field of multipole source in borehole around fluid-saturated porous media. 展开更多
关键词 confining pressure pore pressure fluid-saturated porous media multipole borehole acoustic field
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Physics-embedded machine learning search for Sm-doped PMN-PT piezoelectric ceramics with high performance
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作者 辛睿 王亚祺 +6 位作者 房泽 郑凤基 高雯 付大石 史国庆 刘建一 张永成 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期81-88,共8页
Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(PMN-PT)piezoelectric ceramics have excellent piezoelectric properties and are used in a wide range of applications.Adjusting the solid solution ratios of PMN/PT and different conce... Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(PMN-PT)piezoelectric ceramics have excellent piezoelectric properties and are used in a wide range of applications.Adjusting the solid solution ratios of PMN/PT and different concentrations of elemental doping are the main methods to modulate their piezoelectric coefficients.The combination of these controllable conditions leads to an exponential increase of possible compositions in ceramics,which makes it not easy to extend the sample data by additional experimental or theoretical calculations.In this paper,a physics-embedded machine learning method is proposed to overcome the difficulties in obtaining piezoelectric coefficients and Curie temperatures of Sm-doped PMN-PT ceramics with different components.In contrast to all-data-driven model,physics-embedded machine learning is able to learn nonlinear variation rules based on small datasets through potential correlation between ferroelectric properties.Based on the model outputs,the positions of morphotropic phase boundary(MPB)with different Sm doping amounts are explored.We also find the components with the best piezoelectric property and comprehensive performance.Moreover,we set up a database according to the obtained results,through which we can quickly find the optimal components of Sm-doped PMN-PT ceramics according to our specific needs. 展开更多
关键词 Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(PMN-PT)ceramic physics-embedded machine learning piezoelectric coefficient Curie temperature
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A Comparative Study of the Power-law Relationship between the Pulse width and Energy of Precursor and Main Burst
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作者 Hui-Ying Deng Zhao-Yang Peng +1 位作者 Jia-Ming Chen Dan Zhu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期144-168,共25页
In gamma-ray burst prompt emission,there is still no consistent conclusion if the precursor and main burst share the same origin.In this paper,we try to study this issue based on the relationship between pulse width a... In gamma-ray burst prompt emission,there is still no consistent conclusion if the precursor and main burst share the same origin.In this paper,we try to study this issue based on the relationship between pulse width and energy of the precursor and main burst.We systematically search the light curve data observed by Swift/BAT and Fermi/GBM,and find 13 long bursts with well-structured precursors and main bursts.After fitting the precursor light curve of each different energy channel with the Norris function,we find that there is not only a power-law relationship between precursor width and energy,but also a power-law relationship between the ratio of the rising width to the decaying width and energy.By comparing the relationship between the precursors and the main burst pulses,we find that the distribution of the precursors and the relationship between the power-law indices are roughly the same as those of the main burst.In addition,it is found that the precursor width distribution as well as the upper limit of the pulse width ratio does not exceed 1 and both are asymmetric,which are also consistent with the main burst.These indicate that the precursor and the main burst are indistinguishable,and the precursor and the main burst may have the same physical origin. 展开更多
关键词 methods data analysis-(stars) gamma-ray burst general-shock waves
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Theoretical analysis of the double-differential cross-sections of neutron,proton,deuteron,^(3)He,andαfor the p+^(6) Li reaction
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作者 Fang-Lei Zou Xiao-Jun Sun +10 位作者 Jing-Shang Zhang Hai-Rui Guo Yin-Lu Han Rui-Rui Xu Xi Tao Ji-Min Wang Xiao-Dong Sun Yuan Tian Tao Ye Yong-Li Xu Chun-Tian Liang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期181-197,共17页
Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of l... Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of light nucleus reaction(STLN)is developed to calculate the double-differential cross-sections of the outgoing neutron and light charged particles for the proton-induced^(6) Li reaction.A significant difference is observed between the p+^(6) Li and p+^(7) Li reactions owing to the discrepancies in the energy-level structures of the targets.The reaction channels,including sequential and simultaneous emission processes,are analyzed in detail.Taking the double-differential cross-sections of the outgoing proton as an example,the influence of contaminations(such as^(1) H,^(7)Li,^(12)C,and^(16)O)on the target is identified in terms of the kinetic energy of the first emitted particles.The optical potential parameters of the proton are obtained by fitting the elastic scattering differential cross-sections.The calculated total double-differential cross-sections of the outgoing proton and deuteron at E_(p)=14 MeV agree well with the experimental data for different outgoing angles.Simultaneously,the mixed double differential cross-sections of^(3) He andαare in good agreement with the measurements.The agreement between the measured data and calculated results indicates that the two-body and three-body breakup reactions need to be considered,and the pre-equilibrium reaction mechanism dominates the reaction processes.Based on the STLN model,a PLUNF code for the p+^(6) Li reaction is developed to obtain an ENDF-6-formatted file of the double-differential cross-sections of the nucleon and light composite charged particles. 展开更多
关键词 Statistical theory of light nucleus reaction p+^(6)Li reaction Light composite charged particle Double-differential cross-sections Two-body breakup Three-body breakup
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A Solution of the Cosmological Constant and DE and Arrow of Time, Using Model of a Nonsingular Universe from Rosen from Volume (56) Ettore Majorana International Science Series, Physics, 1991
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作者 Andrew Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第3期925-935,共11页
We reduplicate the Book “Dark Energy” by M. Li, X-D. Li, and Y. Wang, given zero-point energy calculation with an unexpected “length” added to the “width” of a graviton wave just prior to specifying the creation... We reduplicate the Book “Dark Energy” by M. Li, X-D. Li, and Y. Wang, given zero-point energy calculation with an unexpected “length” added to the “width” of a graviton wave just prior to specifying the creation of “gravitons”, using the Rosen and Israelit model of a nonsingular universe. In doing so we are in addition to obtaining a wavelength 10<sup>30</sup> times greater than Planck’s length so we can calculate DE, may be able to with the help of the Rosen and Israelit model have a first approximation as to the arrow of time, and a universe with massive gravity. We have left the particulars of the nonsingular starting point undefined but state that the Rosen and Israelit model postulates initial temperatures of 10<sup>-180</sup> Kelvin and also a value of about Planck temperature, at 10<sup>-3</sup> centimeters radii value which may satisfy initial conditions asked by t’Hooft for describing an arrow of time. A key assumption is that the DE is formed at 10<sup>-3</sup> cm, after an expansion of 10<sup>30</sup> times in radii, from the Planck length radius nonsingular starting point. The given starting point for DE in this set of assumptions is where there is a change in the cosmic acceleration, to a zero value, according to Rosen and Israel, with time <i>t</i> = 1.31 times 10<sup>-42</sup> seconds. That may be where we may specify a potential magnitude, <i>V</i>, which has ties into inflaton physics. The particulars of the model from Rosen and Israelit allow a solution to be found, without discussion of where that nonsingular starting point came from, a point the author found in need of drastic remedies and fixes. 展开更多
关键词 Minimum Scale Factor Cosmological Constant Space-Time Bubble DE Arrow of Time
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Low-energy inelastic electron scattering from carbon monoxide:Excitation and de-excitation of the X^(1)Σ^(+),a^(3)Π,a'^(3)∑^(+),A^(1)Π,d^(3)Δ,e^(3)∑^(-),I^(1)∑^(-)and D^(1)Δelectronic states
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作者 卫鹏宇 黄朝文 +1 位作者 程新路 张红 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期444-450,共7页
Cross-sections for electronic excitation and de-excitation among the ground state and lowest-lying seven electronic excited states of carbon monoxide(CO)by low-energy electron impact are computed using the R-matrix me... Cross-sections for electronic excitation and de-excitation among the ground state and lowest-lying seven electronic excited states of carbon monoxide(CO)by low-energy electron impact are computed using the R-matrix method.The excitation cross-sections from the ground state to the electronic states a^(3)Π,a'^(3)Σ^(+)+and A^(1)Πagree with previous experimental and theoretical results.In addition,the cross-sections for the I^(1)Σ^(+)-and D^(1)Δstates of CO,which will cascade to CO a'^(3)Σ^(+)+and A^(1)Πstates,are calculated.Furthermore,in contrast to the typical increase in electronic excitation cross-sections with collision energy,the de-excitation cross-sections show a negative trend with increasing energy. 展开更多
关键词 electron-CO collision electronic excitation CROSS-SECTIONS R-matrix method
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Relationship between polyhedral structures formed by tangent planes of ellipsoidal particles and system sound velocity
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作者 Cheng-Bo Li Lin Bao Chuang Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期448-456,共9页
Internal polyhedral structures of a granular system can be investigated using the Voronoi tessellations.This technique has gained increasing recognition in research of kinetic properties of granular flows.For systems ... Internal polyhedral structures of a granular system can be investigated using the Voronoi tessellations.This technique has gained increasing recognition in research of kinetic properties of granular flows.For systems with mono-sized spherical particles,Voronoi tessellations can be utilized,while radial Voronoi tessellations are necessary for analyzing systems with multi-sized spherical particles.However,research about polyhedral structures of non-spherical particle systems is limited.We utilize the discrete element method to simulate a system of ellipsoidal particles,defined by the equation(x a)2+(y1)2+(z 1/a)2=1,where a ranges from 1.1 to 2.0.The system is then dissected by using tangent planes at the contact points,and the geometric quantities of the resulting polyhedra in different shaped systems,such as surface area,volume,number of vertices,number of edges,and number of faces,are calculated.Meanwhile,the longitudinal and transverse wave velocities within the system are calculated with the time-of-flight method.The results demonstrate a strong correlation between the sound velocity of the system and the geometry of the dissected polyhedra.The sound velocity of the system increases with the increase in a,peaking at a=1.3,and then decreases as a continues to increase.The average volume,surface area,number of vertices,number of edges,and number of faces of the polyhedra decrease with the increase in sound velocity.That is,these quantities initially decrease with the increase in a,reaching minima at a=1.3,and then increase with further increase of a.The relationship between sound velocity and the geometric quantities of the dissected polyhedra can serve as a reference for acoustic material design. 展开更多
关键词 discrete element method Voronoi tessellation polyhedral structure sound velocity
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