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ENERGY LEVELS OF STRONG COUPLING MAGNETOPOLARON IN QUANTUM WIRE 被引量:7
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作者 ZHOU Hai-yang(周海阳) +1 位作者 GU Shi-wei(顾世洧) 《Journal of Shanghai Jiaotong university(Science)》 EI 2002年第1期100-104,共5页
With the use of variational method of Pekar type, this paper studied the energy levels of magnetopolaron in quantum wire with strong electron phonon interaction. The magnetopolaron binding energy in the ground state a... With the use of variational method of Pekar type, this paper studied the energy levels of magnetopolaron in quantum wire with strong electron phonon interaction. The magnetopolaron binding energy in the ground state and in the excited state, as well as the resonance frequency of magnetopolaron were calculated. Their dependence on the cyclotron frequency and the confinement strength of quantum wire was depicted. The limiting case of bulk type and strict two dimensional type was discussed. 展开更多
关键词 STRONG COUPLING MAGNETOPOLARON QUANTUM WIRE
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Optical diode behavior of photonic crystal structure with asymmetric Kerr defect 被引量:2
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作者 李文慧 陈历学 +1 位作者 丁卫强 刘树田 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第4期545-547,共3页
Optical diode behavior of asymmetric one-dimensional photonic crystal with Kerr defect is numerically investigated using nonlinear transfer matrix method. In the linear case, the intensity and the phase of transmitted... Optical diode behavior of asymmetric one-dimensional photonic crystal with Kerr defect is numerically investigated using nonlinear transfer matrix method. In the linear case, the intensity and the phase of transmitted field are the same for the forward and backward operations. In the nonlinear case, however, the transmitted intensities are much different for the two operations, which display diode characteristic. Physical origin of the anisotropic transmission lies in the different localizations in the defect layer of the two operations. 展开更多
关键词 光学转换 光学材料 刻尔效应 光二极管 晶体结构
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Under the surface:Pressure-induced planetary-scale waves,volcanic lightning,and gaseous clouds caused by the submarine eruption of Hunga Tonga-Hunga Ha'apai volcano 被引量:7
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作者 David A.Yuen Melissa A.Scruggs +11 位作者 Frank J.Spera Yingcai Zheng Hao Hu Stephen R.McNutt Glenn Thompson Kyle Mandli Barry R.Keller Songqiao Shawn Wei Zhigang Peng Zili Zhou Francesco Mulargia Yuichiro Tanioka 《Earthquake Research Advances》 CSCD 2022年第3期1-13,共13页
We present a narrative of the eruptive events culminating in the cataclysmic January 15, 2022 eruption of Hunga Tonga-Hunga Ha’apai Volcano by synthesizing diverse preliminary seismic, volcanological, sound wave, and... We present a narrative of the eruptive events culminating in the cataclysmic January 15, 2022 eruption of Hunga Tonga-Hunga Ha’apai Volcano by synthesizing diverse preliminary seismic, volcanological, sound wave, and lightning data available within the first few weeks after the eruption occurred. The first hour of eruptive activity produced fast-propagating tsunami waves, long-period seismic waves, loud audible sound waves, infrasonic waves, exceptionally intense volcanic lightning and an unsteady volcanic plume that transiently reached-at 58km-the Earth’s mesosphere. Energetic seismic signals were recorded worldwide and the globally stacked seismogram showed episodic seismic events within the most intense periods of phreatoplinian activity, and they correlated well with the infrasound pressure waveform recorded in Fiji. Gravity wave signals were strong enough to be observed over the entire planet in just the first few hours, with some circling the Earth multiple times subsequently. These large-amplitude, long-wavelength atmospheric disturbances come from the Earth’s atmosphere being forced by the magmatic mixture of tephra, melt and gasses emitted by the unsteady but quasicontinuous eruption from 0402±1–1800 UTC on January 15, 2022. Atmospheric forcing lasted much longer than rupturing from large earthquakes recorded on modern instruments, producing a type of shock wave that originated from the interaction between compressed air and ambient(wavy) sea surface. This scenario differs from conventional ideas of earthquake slip, landslides, or caldera collapse-generated tsunami waves because of the enormous(~1000x) volumetric change due to the supercritical nature of volatiles associated with the hot,volatile-rich phreatoplinian plume. The time series of plume altitude can be translated to volumetric discharge and mass flow rate. For an eruption duration of ~12 h, the eruptive volume and mass are estimated at 1.9 km^(3) and~2 900 Tg, respectively, corresponding to a VEI of 5–6 for this event. The high frequency and intensity of lightning was enhanced by the production of fine ash due to magma-seawater interaction with concomitant high charge per unit mass and the high pre-eruptive concentration of dissolved volatiles. Analysis of lightning flash frequencies provides a rapid metric for plume activity and eruption magnitude. Many aspects of this eruption await further investigation by multidisciplinary teams. It represents a unique opportunity for fundamental research regarding the complex, non-linear behavior of high energetic volcanic eruptions and attendant phenomena, with critical implications for hazard mitigation, volcano forecasting, and first-response efforts in future disasters. 展开更多
关键词 Hunga Tonga-Hunga Ha'apai Atmospheric pressure wave Tsunami wave Volcanic lightning Phreatoplinian eruption
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THE NONLINEAR INTERACTION OF VORTEX RINGS WITH A FREE SURFACE
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作者 叶取源 C.K.Chu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1997年第2期120-129,共10页
Nonlinear interactions of vortex rings with a free surface are considered in an incompressible, ideal fluid using the vortex contour dynamics technique and the boundary integral equation method. The flow is axisymmetr... Nonlinear interactions of vortex rings with a free surface are considered in an incompressible, ideal fluid using the vortex contour dynamics technique and the boundary integral equation method. The flow is axisymmetric and the vorticity is linearly distributed in the vortex. Effects of the gravity and the surface tension as well as the initial geometric parameter of the vortex on the interaction process are investigated in considerable detail. The interaction process may be divided into three major stages: the vortex free-traveling stage, the collision stage, and the vortex stretching and rebounding stage. Time evolutions of both the vortex and free surface under various conditions are provided and analyzed. Two kinds of waves exist on the free surface during interaction. In a special case where the gravity and surface tension are very weak or the vortex is very strong, an electric-bulb-like 'cavity' is formed an the free surface and the vortex is trapped in the 'cavity' for quite a. long time, resulting in a large amount, of fluid above the mean fluid surface. 展开更多
关键词 vortex ring vortex dynamics contour dynamics nonlinear free surface
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The revision on heat capacity of Einstein’s solid model
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作者 王爱坤 周国香 +1 位作者 李国昌 薛建华 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第3期325-327,共3页
This paper is based on Einstein’s supposition about crystal lattice vibration, which states that when Einstein’s temperature ΘE is not less than the crystal temperature T but less than 2T, the express... This paper is based on Einstein’s supposition about crystal lattice vibration, which states that when Einstein’s temperature ΘE is not less than the crystal temperature T but less than 2T, the expression of crystal molar heat capacity changes to the Dulong-Petit equation Cv=3R. Thereby this equation can explain why crystal molar heat capacity equals about 3R not only at low temperatures but also at normal temperatures for many kinds of metals. It can be calculated that the nonlinear interaction among atoms contributes to the molar heat capacity using the coefficient of expansion β and the Grüneisen constant γ. The result is that the relative error between the theoretical and the experimental value of the molar heat capacity is reduced greatly for many kinds of metals, especially for metals of IA. The relative error can be cut by about 17%. 展开更多
关键词 爱因斯坦固体模型 摩尔热容积 线性交互作用 扩展系数
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Application of HPC and big data in post-pandemic times
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作者 Henry M.Tufo David A.Yuen +3 位作者 Gabriele Morra Matthew G.Knepley Bei Zhang Shi Chen 《Earthquake Research Advances》 CSCD 2021年第3期21-28,共8页
We lay out the ramifications of the 2020 pandemic for all people in geosciences,especially the young,and argue for significant changes on training and career development.We focus primarily on its devastating impact in... We lay out the ramifications of the 2020 pandemic for all people in geosciences,especially the young,and argue for significant changes on training and career development.We focus primarily on its devastating impact in USA and compare with that in other countries especially China.We review the potential effect for the next four years or so on the aspirations of an academic career versus more realistic career goals.We urge people in mid-career about the need to reassess previous goals.We stress the need for students or researchers to acquire technical skills in high-performance computing(HPC),data analytics,artificial intelligence,and/or visualization along with a broad set of technical skills in applied computer science and mathematics.We give advice about hot prospects in several areas that have great potential for advancement in the coming decade,such as visualization,deep learning,quantum computing and information,and cloud computing,all of which lie within the aegis of HPC.Our forecast is that the pandemic will significantly reshape the job landscape and career paths for both young and established researchers and we discuss bluntly the dire situation facing junior people in geosciences in the aftermath of the pandemic around the world until 2024. 展开更多
关键词 GEOPHYSICS High-performance computing Higher education Post-pandemic era
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Finite Element Delamination Study of a Notched Composite Plate under Flexural Loads
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作者 Alann Andre Soren Nilsson Leif E. Asp 《材料科学与工程(中英文版)》 2010年第8期66-73,共8页
关键词 有限元分析 弯曲载荷 复合材料板 缺口 有限元模型 ABAQUS 载荷位移曲线 有限元软件
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Thermodynamic Modelling of a 10-kW Ammonia-Water Absorption Machine
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作者 Fatimata Dione Ababacar Thiam +1 位作者 Djicknoum Diouf Amadou-Seidou Maiga 《Journal of Energy and Power Engineering》 2022年第5期213-221,共9页
Absorption chillers are cooling units usually powered by renewable energy or waste heat.Their performance generally depends on the temperatures of the heat source,the ambient and the medium to be cooled.The present wo... Absorption chillers are cooling units usually powered by renewable energy or waste heat.Their performance generally depends on the temperatures of the heat source,the ambient and the medium to be cooled.The present work deals with the thermodynamic study of a 10 kW NH3/H2O absorption machine in order to find the COP(coefficient of performance).The first and second laws of thermodynamics were used for the operating conditions.The thermodynamic properties of the NH3/H2O mixture were determined using the EES(Engineering Equation Solver)software.The results of the simulation of the machine were validated with the results of the literature.After validation,the program was used to simulate a 10-kW NH3/H2O absorption machine for milk conservation/cold storage in northern Senegal.The simulation results of the 10-kW ammonia-water absorption machine give an acceptable COP of 0.521 with a milk storage temperature of 4°C. 展开更多
关键词 ABSORPTION AMMONIA-WATER COP EES
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Research on the ultraweak photon emission from anti-cancer plants
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作者 Ping Wu Xiang He 《Journal of Biomedical Science and Engineering》 2009年第3期155-157,共3页
UPE (Ultraweak photon emission) is one kind of a common phenomenon in biological organisms. It contains a wealth of information of biological functions. In this paper, single photon counting system is used to measure ... UPE (Ultraweak photon emission) is one kind of a common phenomenon in biological organisms. It contains a wealth of information of biological functions. In this paper, single photon counting system is used to measure UPE of some anti- cancer herbal plants. For the plants, the changes of UPE under different water condition are stud-ied and the varying laws of ultraweak photon number with time are analysed. The results are higher fit double exponential decay law. 展开更多
关键词 Ultraweak PHOTON Emission PHOTON COUNTING Barbed Skullcap HERB Pedate Pinallia Jackinthepulpit RHIZOME Cochinchnese ASPARAGUS Root Fitting
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Why a new journal like Earthquake Research Advances (ERA)?
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作者 David A.Yuen 《Earthquake Research Advances》 CSCD 2021年第1期3-3,共1页
In these difficult and hard times of pandemic,why another new journal,like ERA,should come out?What is ERA?It is a journal sponsored by the China Earthquake Networks Center and co-sponsored by the School of Earth and ... In these difficult and hard times of pandemic,why another new journal,like ERA,should come out?What is ERA?It is a journal sponsored by the China Earthquake Networks Center and co-sponsored by the School of Earth and Space Sciences,University of Science and Technology in China.The reason for establishing this journal is to start something innovative and forge a path to a new leaf in earthquake-related research.You will see below that this journal is not afraid to dive into new topics. 展开更多
关键词 China EARTHQUAKE EARTHQUAKE
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