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转场,草原上的四季风景
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作者 毛兔 《民族论坛》 2006年第11期20-21,共2页
关键词 《转场 草原上的四季风景》 中国 当代文学 杂文
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Interface engineering via temperature-dependent self-transformation on SnS_(2)/SnS for enhanced piezocatalysis
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作者 Wenrou Tian Jun Han +4 位作者 Najun Li Dongyun Chen Qingfeng Xu Hua Li Jianmei Lu 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期166-179,共14页
Heterojunction has been widely used in vibration-driven piezocatalysis for enhanced charges separation,while the weak interfaces seriously affect the efficiency during mechanical deformations due to prepared by tradit... Heterojunction has been widely used in vibration-driven piezocatalysis for enhanced charges separation,while the weak interfaces seriously affect the efficiency during mechanical deformations due to prepared by traditional step-by-step methods.Herein,the intimate contact interfaces with shared S atoms are ingeniously constructed in SnS_(2)/SnS anchored on porous carbon by effective interface engineering,which is in-situ derived from temperature-dependent self-transformation of SnS_(2).Benefiting from intimate contact interfaces,the piezoelectricity is remarkably improved due to the larger interfacial dipole moment caused by uneven distribution of charges.Importantly,vibration-induced piezoelectric polarization field strengthens the interfacial electric field to further promote the separation and migration of charges.The dynamic charges then transfer in porous carbon with high conductivity and adsorption for significantly improved piezocatalytic activity.The degradation efficiency of bisphenol A(BPA)is 6.3 times higher than SnS_(2) and H_(2) evolution rate is increased by 3.8 times.Compared with SnS_(2)/SnS prepared by two-step solvothermal method,the degradation efficiency of BPA and H2 evolution activity are increased by 3 and 2 times,respectively.It provides a theoretical guidance for developing various multiphase structural piezocatalyst with strong interface interactions to improve the piezocatalytic efficiency. 展开更多
关键词 Piezocatalysis SELF-TRANSFORMATION Phase junction Interfacial field Polarized field
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Corrosion behavior of T2 copper in 3.5% sodium chloride solution treated by rotating electromagnetic field 被引量:5
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作者 张鹏 朱强 +2 位作者 苏倩 郭斌 程树康 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第5期1439-1446,共8页
Copper is susceptible to producing corrosion problems in corrosive environments, which leads to serious safety problems. Thus, investigating the corrosion behavior of copper is of great significance. The effects of ro... Copper is susceptible to producing corrosion problems in corrosive environments, which leads to serious safety problems. Thus, investigating the corrosion behavior of copper is of great significance. The effects of rotating electromagnetic field on corrosion behavior of T2 copper in 3.5% sodium chloride solution with electrochemical measurements were investigated. The results showed that rotating electromagnetic field changed properties of 3.5% sodium chloride solution by increasing the values of temperature and pH and decreasing the values of conductivity and dissolved oxygen. The rotating electromagnetic field improved the corrosion resistance of T2 copper. The corrosion products of T2 copper in treated 3.5% sodium chloride solution were composed of Cu20 and CuCl. The low corrosion rate of T2 copper was resulted from the decrease of dissolved oxygen in 3.5% sodium chloride solution treated by rotating electromagnetic field. 展开更多
关键词 corrosion behavior rotating electromagnetic field electrochemical measurement COPPER
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Electric field assisted chemical conversion process of AZ91D magnesium alloy in HCO_3^-/CO_3^(2-) solution 被引量:3
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作者 巴志新 章晓波 +3 位作者 王章忠 方信贤 董强胜 王强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期3818-3824,共7页
A new method for synthesizing Mg-Al hydrotalcite conversion coating on AZ91D Mg alloy was developed by the application of electric field (EF). By using EF technique, the formation time of the coating can be signific... A new method for synthesizing Mg-Al hydrotalcite conversion coating on AZ91D Mg alloy was developed by the application of electric field (EF). By using EF technique, the formation time of the coating can be significantly reduced. The SEM results indicate that a continuous and compact Mg-Al hydrotalcite coating is formed on the surface of Mg alloy after short time EF treatment. However, a long time treatment would make the coating partially exfoliate. The corrosion current density (Jcor ) of the coated sample (EF1+1 h) is approximately two orders of magnitude lower than that of Mg alloy substrate. The test of electrochemical impedance spectroscopy (EIS) and immersion corrosion also suggest that the coating can effectively protect Mg alloy against corrosion. 展开更多
关键词 magnesium alloy Mg-Al hydrotalcite conversion coating corrosion resistance electric field
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Ocean surface currents retrieval based on the satellite remote sensing data 被引量:1
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作者 安玉柱 陈奕德 +2 位作者 张韧 王辉赞 陈建 《Marine Science Bulletin》 CAS 2013年第2期46-58,共13页
The ocean surface currents are reconstructed from the satellite remote sensing data containing altimeter-derived sea surface height and QuikSCAT satellite-derived wind data. Based on the method proposed by Lagerloef, ... The ocean surface currents are reconstructed from the satellite remote sensing data containing altimeter-derived sea surface height and QuikSCAT satellite-derived wind data. Based on the method proposed by Lagerloef, a global weekly 0.5°×0.5°ocean surface current product was obtained over the period 2000 - 2008 by combining the geostrophic currents estimated from sea surface height with Ekman current estimated from the wind stress. Particularly, weight functions were introduced when calculating the Ekman currents to eliminate the discontinuity near 25°S and 25°N. These satellite-derived currents have been compared with TAO current meter and the SCUD product, respectively. The comparison showed that satellite-derived currents not only could capture the characteristics of ocean surface currents but also had high accuracy and reliability. The result showed that this innovatory method was effective. 展开更多
关键词 satellite altimeter data QuikSCAT wind field surface geostrophic current Ekman current
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Comprehensive Performance Evaluation of Family Farms from the Perspective of Land Transfer——Taking Rudong County as an Example
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作者 孙燕 张云鹏 戴福鑫 《Agricultural Science & Technology》 CAS 2017年第12期2638-2643,共6页
With the reform of agriculture, family farms have become hot spots in the reform of agricultural management system. Taking Rudong County of Jiangsu Province for an example, the land transfer performance of family farm... With the reform of agriculture, family farms have become hot spots in the reform of agricultural management system. Taking Rudong County of Jiangsu Province for an example, the land transfer performance of family farms was evalu- ated using the first hand data from field investigation by building an index system for comprehensive performance evaluation of family farm land transfer covering three dimensions of economy, society and ecology. The results show that land transfer in family farm mode has realized the scale management of land, enhanced the agri- cultural level of science and technology, effectively promoted the structural adjust- ment of agriculture and income increase of farmers, advanced the development of eco-agriculture, and achieved good economic and social performances. However, in the development process of family farms, inputs of agro-chemicals, fertilizers and other agro-products have brought about the eco-environmental problems, which are still worth noting. 展开更多
关键词 Land transfer Comprehensive performance EVALUATION Family farm Rudong County
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Meshless simulation for skeleton driven elastic deformation 被引量:1
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作者 SONG Chao ZHANG Hong-xin +1 位作者 HUANG Jin BAO Hu-jun 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第9期1596-1602,共7页
A meshless simulation system is presented for elastic deformation driven by skeleton in this paper. In this system, we propose a new method for calculating node rotation while applying a similar technique with stiffne... A meshless simulation system is presented for elastic deformation driven by skeleton in this paper. In this system, we propose a new method for calculating node rotation while applying a similar technique with stiffness warping to tackle the nonlinear large deformation. In our method, all node rotations are evaluated from sampling points in attached skeleton by con- structing and solving the diffusion partial differential equation. The experiments indicated that the method can enhance the sta- bility of the dynamics and avoid fussy sub-step calculation in static deformation edition. Moreover, rational deformation results for the area around the skeleton joints can be simulated without user interaction by adopting the simplified technique. 展开更多
关键词 Physically-based deformation Skeleton driven Meshless methods Rotation field
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Magnetic Field Analysis of Interior Composite-Rotor Controllable-Flux Permanent Magnet Synchronous Machine 被引量:5
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作者 陈益广 潘巍 +1 位作者 沈勇环 唐任远 《Transactions of Tianjin University》 EI CAS 2006年第5期330-334,共5页
Conventional permanent magnet synchronous machine (PMSM) has the problem of large stator copper loss and narrow speed range. To solve this problem, an interior composite-rotor controllable-flux PMSM adaptive to multi-... Conventional permanent magnet synchronous machine (PMSM) has the problem of large stator copper loss and narrow speed range. To solve this problem, an interior composite-rotor controllable-flux PMSM adaptive to multi-polar is proposed. This machine has the characteristics of low stator copper loss and wide-speed operation. The half-radial-set and half-tangential-set permanent magnets (PMs) are NdFeB that has high remanent flux density and high coercive force. The tangential-set PMs are AlNiCo that has high remanent flux density and low coercive force. By applying the pulse of d-axis stator current i_d, the magnetized intensity and direction of AlNiCo can be controlled. The flux created by NdFeB is repelled to stator and air-gap PM-flux is intensified, or is partially bypassed by AlNiCo in the rotor, so the air-gap PM-flux is weakened. The internal magnetic field distribution in two ultra magnetized situations is analyzed by finite element method. The dimension of PMs and magnetic structure are demonstrated. Especially when the q-axis magnetic resistance is larger and the q-axis inductance is smaller, the result of flux-weakening is better and the influence of armature reaction on air-gap PM-flux is weakened. 展开更多
关键词 controllable-flux PMSM memory motor internal composite-rotor finite element analysis
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A novel system for Agrobacterium-mediated transformation of wheat(Triticum aestivum L.) cells 被引量:1
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作者 XUYAO BAOJIANLI JINGFENJIA 《Cell Research》 SCIE CAS CSCD 1993年第1期48-48,50-60,共12页
A new approach for transforming the cultured cells of wheat(Triticum aestivum L. cv. Ganmai 8) was developed using Agrobacterium tumefaciens. The features of the optimum procedure were: (a) both combined synthetic sig... A new approach for transforming the cultured cells of wheat(Triticum aestivum L. cv. Ganmai 8) was developed using Agrobacterium tumefaciens. The features of the optimum procedure were: (a) both combined synthetic signal molecules and multiple natural extracts from susceptible plants were used to pretreat the primary vigorous Agrobacterium(PVA) cells for approximately 16 h; (b) the gyratory magnetic field condition was used during cocultivation; (c) the cocultivating period and selecting condition were modified; (d) the recipient cells were at exuberant metabolism and active division while infected with Agrobacterium. Both neomycin phosphotransferase and nopaline synthase assays demonstrated the expression of NPT II and NOS genes, located on the T-DNA segment of chimaeric plasmid pGV3850::1103neo, in transformed wheat cell colonies by adopting the techniques of dot blot, ndPAGE or high voltage paper electrophoresis. Integration of the foreign genes into wheat genome was confirmed by Southern blot hybridization. Moreover, a relatively rational method was described for the estimation of transformation frequencies from cultured cell levels. 展开更多
关键词 genetic engineering gyratory magnetic field natural susceptible extracts synthetic signals transformation system wheat cells.
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Heisenberg Model in a Rotating Magnetic Field 被引量:1
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作者 LINQiong-Gui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4期621-626,共6页
We study the Hcisenberg moder under the influence of a rotating magnetic field. By using a time- dependent unitary transformation, the time evolution operator for the Schrodinger equation is obtained, which involves n... We study the Hcisenberg moder under the influence of a rotating magnetic field. By using a time- dependent unitary transformation, the time evolution operator for the Schrodinger equation is obtained, which involves no chronological product. The spin vectors (mean values of the spin operators) are obtained as explicit functions of time in the most general case. A series of cyclic solutions are presented. The nonadiabatic geometric phases of these cyclic solutions are caleulated, and are expressed in terms of the solid angle subtended by the closed trace of thc total spin vector, as well as in terms of those of the individual spins. 展开更多
关键词 Heisenberg model rotating magnetic field cyclic solutions geometric phase
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Enhancement of Squeezing in Two-Photon Jaynes-Cummings Model with Atomic Measurement 被引量:3
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作者 YE Sai-Yun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1期147-150,共4页
We investigate the squeezing properties of the cavity field in the degenerate two-photon Jaynes Cummings model. Compared with the one-photon Jaynes-Cummings model, the squeezing is more pronounced in the case of two-p... We investigate the squeezing properties of the cavity field in the degenerate two-photon Jaynes Cummings model. Compared with the one-photon Jaynes-Cummings model, the squeezing is more pronounced in the case of two-photon Jaynes-Cummings model under certain conditions. 展开更多
关键词 squeezed state two-photon transitions selective atomic measurement
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Equivalent Doping Transformation Method for Predicting Breakdown Voltage and Peak Field at Breakdown of Epitaxial-Diffused Punch-Through Junction
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作者 何进 张兴 +1 位作者 黄如 王阳元 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第3期256-260,共5页
Based on a new semi empirical analytical method, namely equivalent doping transformation, the breakdown voltage and the peak field of the epitaxial diffused punch through junction have been obtained. The basic prin... Based on a new semi empirical analytical method, namely equivalent doping transformation, the breakdown voltage and the peak field of the epitaxial diffused punch through junction have been obtained. The basic principle of this method is introduced and a set of breakdown voltage and peak field plots are provided for the optimum design of the low voltage power devices. It shows that the analytical results coincide with the previous numerical simulation well. 展开更多
关键词 epitaxial diffused punch through junction breakdown voltage peak field equivalent doping transformation
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Reflection spectra of fiber Bragg gratings in quadratic strain field 被引量:2
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作者 JIANG Meng ZHANG Wei-gang TU Qin-chang LIU Hai-tao ZHANG Qi 《Optoelectronics Letters》 EI 2006年第6期419-421,共3页
We theoretically analyze the reflection spectra of the fiber Bragg gratings in the quadratic strain field,and resolve the numerical value with transfer matrix method.When the value of pressure is changed,we can obtain... We theoretically analyze the reflection spectra of the fiber Bragg gratings in the quadratic strain field,and resolve the numerical value with transfer matrix method.When the value of pressure is changed,we can obtain diverse reflection spectra of the fiber Bragg gratings,which is in good accordance with the experimental results. 展开更多
关键词 反射光谱 光纤BRAGG光栅 二次应力场 转移矩阵法
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Kinetics of Conversion of Methane with Electric Field Enhanced Plasma 被引量:1
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作者 王保伟 许根慧 孙洪伟 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第1期131-133,共3页
Methane conversion was studied with electric field enhanced plasma (EFEP) technique at the atmosphere pressure and low temperature ranging from 323 K to 373 K. The conversion of methane is up to 60%-80%. The kinetics ... Methane conversion was studied with electric field enhanced plasma (EFEP) technique at the atmosphere pressure and low temperature ranging from 323 K to 373 K. The conversion of methane is up to 60%-80%. The kinetics of methane conversion was studied using naicroreactor. The reaction model of power function type was obtained as: r = 90.99exp (-26980/RT)C0226A(mol·m-3·s-1). The global kinetics parameters were calculated by the variable simple-pure shape method. The calculating results are in good agreement with experimental data. 展开更多
关键词 METHANE KINETICS electric field PLASMA
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Matched-field inversion of sound speed profile in shallow water using a parallel genetic algorithm 被引量:9
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作者 余炎欣 李整林 何利 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第5期1080-1085,共6页
A sound speed profile plays an important role in shallow water sound propagation.Concurrent with in-situ measurements,many inversion methods,such as matched-field inversion,have been put forward to invert the sound sp... A sound speed profile plays an important role in shallow water sound propagation.Concurrent with in-situ measurements,many inversion methods,such as matched-field inversion,have been put forward to invert the sound speed profile from acoustic signals.However,the time cost of matched-field inversion may be very high in replica field calculations.We studied the feasibility and robustness of an acoustic tomography scheme with matched-field processing in shallow water,and described the sound speed profile by empirical orthogonal functions.We analyzed the acoustic signals from a vertical line array in ASIAEX2001 in the East China Sea to invert sound speed profiles with estimated empirical orthogonal functions and a parallel genetic algorithm to speed up the inversion.The results show that the inverted sound speed profiles are in good agreement with conductivity-temperature-depth measurements.Moreover,a posteriori probability analysis is carried out to verify the inversion results. 展开更多
关键词 matched-field processing sound speed profile parallel genetic algorithm
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Effect of low-frequency rotary electromagnetic-field on solidification structure of continuous casting austenitic stainless steel 被引量:3
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作者 周书才 白晨光 +3 位作者 雷亚 任正德 曹鹏军 杨治立 《Journal of Central South University》 SCIE EI CAS 2009年第3期360-364,共5页
To understand the solidification behavior of austenitic stainless steel in rotary electromagnetic-field, the influence of low-frequency rotary electromagnetic-field on solidification structure of austenitic stainless ... To understand the solidification behavior of austenitic stainless steel in rotary electromagnetic-field, the influence of low-frequency rotary electromagnetic-field on solidification structure of austenitic stainless steel in horizontal continuous casting was investigated based on industrial experiments. The results show that the solidification structure of austenitic stainless steel can be remarkably refined, the central porosity and shrinkage cavity can be remarkably decreased, and the equiaxed grains zone are enlarged by means of application of appropriate low-frequency electromagnetic-field parameters. The industrial trials verify that the stirring intensity of austenitic stainless steel should be higher compared with that of plain carbon steel. Electromagnetic stirring affects the macrostructure even if the average magnetic flux density of the electromagnetic stirring reaches 90 mT (amplitude reaches 141 mT) with the frequency of 3-4 Hz. Due to a higher viscosity, rotating speed of molten stainless steel is 20%-30% lower than that of molten carbon steel in the same magnetic flux density. 展开更多
关键词 horizontal continuous casting austenitic stainless steel electromagnetic stirring equiaxed grains central porosity
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Influence of Bipartite Qubit Coupling on Geometric Phase
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作者 XING Lei LIANG Mai-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1X期51-54,共4页
The geometric phase of the bipartite Heisenberg spin-1/2 system with one spin driven by rotating magnetic field is investigated. It is found that in the one-site drive case, the intersubsystem coupling can be equivale... The geometric phase of the bipartite Heisenberg spin-1/2 system with one spin driven by rotating magnetic field is investigated. It is found that in the one-site drive case, the intersubsystem coupling can be equivalent to a static quasi-magnetic field in the parameter space. This perspective has satisfactorily explained the irregular asymptote effect of geometric phase. We discuss the property of the two-site magnetic drive spin system and discover that a stationary state with no geometric phase shift is generated. 展开更多
关键词 geometric phase Heisenberg bipartite system rotating magnetic field
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Three-dimensional transformation of magnetization direction and magnetic field component at low latitudes based on vertical relationship 被引量:3
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作者 He Tao Xiong Sheng-Qing Wang Wan-Yin 《Applied Geophysics》 SCIE CSCD 2022年第1期91-106,145,共17页
The transformation of the magnetization direction and the magnetic fi eld component is one of the important methods in magnetic data processing and transformation,which can be conducted in both wavenumber and spatial ... The transformation of the magnetization direction and the magnetic fi eld component is one of the important methods in magnetic data processing and transformation,which can be conducted in both wavenumber and spatial domains.The transformation method in the wavenumber domain has simpler processing expression and higher processing effi ciency than in the spatial domain;however,they are unstable at low latitude.In this paper,the conclusion that the sum is 0 of two vertical magnetic fi eld components(magnetization inclinations are also perpendicular)in 2D is used for the 3D transformation of the magnetization direction and the magnetic field component.In addition,the transformation method at low latitudes based on vertical relationship(VMT)is proposed,which is an iterative algorithm that converts the transformation of the magnetization direction and the magnetic field component at the low latitude into the high latitude.This method restrains the instability of transformation of constant and variable magnetization direction and magnetic fi eld components in low latitudes.The accuracy,stability,and practicality are verifi ed from synthetic models and real data. 展开更多
关键词 the transformation of magnetization direction and magnetic field component wavenumber domain low latitudes vertical relationship iterative algorithm.
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Longitudinal-Random-Field Mixed Ising Model with Arbitrary Spins
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作者 梁雅秋 魏国柱 +1 位作者 徐晓娟 宋国利 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第5期957-962,共6页
The longitudinal-random-fieM mixed Ising model consisting of arbitrary spin values has been studied by the use of an effective field theory with correlations (EFT). The phase diagrams of systems with mixed spins: ... The longitudinal-random-fieM mixed Ising model consisting of arbitrary spin values has been studied by the use of an effective field theory with correlations (EFT). The phase diagrams of systems with mixed spins: σ = 1/2, S = 1; σ = 1/2, S = 3/2 are plotted. Not only the discontinuity at T = 0 K, is found when both longitudinal fields are trimodal distributed, but also the trieritical behavior is observed in these phase diagrams between the bimodal and trimodal distributions of longitudinal fields, which is different from the single-spin one. The appearance of tricritical point is independent of the coordination number and spin values. 展开更多
关键词 mixed Ising model random field phase diagram tricritical point
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Influence of External Magnetic Fields on Tunneling of Spin-1 Bose Condensate
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作者 YUZhao-Xian JIAOZhi-Yong SUNJin-Zuo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期353-356,共4页
In this letter, we have studied the influence of the external magnetic fields on tunneling of the spin-1 Bose condensate. We find that the population transfer between spin-0 and spin-±1 exhibits the step structur... In this letter, we have studied the influence of the external magnetic fields on tunneling of the spin-1 Bose condensate. We find that the population transfer between spin-0 and spin-±1 exhibits the step structure under the external cosinusoidal magnetic field and a combination of static and cosinusoidal one, respectively. Compared with the longitudinal component of the external magnetic field, the smaller the transverse component of the magnetic field is, the larger the time scale of exhibiting the step structure does. The tunneling current may exhibit periodically oscillation behavior when the ratio of the transverse component of the magnetic field is smaller than that of the longitudinal component, otherwise it exhibits a damply oscillating behavior. This means that the dynamical spin localization can be adjusted by the external magnetic fields. 展开更多
关键词 TUNNELING population transfer spinor bose condensate
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