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Phase transition in a two-dimensional Ising ferromagnet based on the generalized zero-temperature Glauber dynamics
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作者 孟庆宽 冯东太 +1 位作者 高绪团 梅玉雪 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期461-465,共5页
At zero temperature, based on the Ising model, the phase transition in a two-dimensional square lattice is studied using the generalized zero-temperature Glauber dynamics. Using Monte Carlo (MC) renormalization grou... At zero temperature, based on the Ising model, the phase transition in a two-dimensional square lattice is studied using the generalized zero-temperature Glauber dynamics. Using Monte Carlo (MC) renormalization group methods, the static critical exponents and the dynamic exponent are studied; the type of phase transition is found to be of the first order. 展开更多
关键词 zero-temperature Glauber dynamics phase transition Monte Carlo renormalization group
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Compositional Distribution and Growth Mode of Garnet Porphyroblasts during Deformation and Metamorphism 被引量:1
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作者 ZHAOGuiping LIUShuwen LIUXiaohan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期186-190,共5页
Although porphyroblast microstructures play an important role in structural and metamorphic studies, there are still controversies in the interpretation. The focus is how porphyroblasts grow during deformation and met... Although porphyroblast microstructures play an important role in structural and metamorphic studies, there are still controversies in the interpretation. The focus is how porphyroblasts grow during deformation and metamorphism. In this paper, we introduce a new approach, the Synchrotron Radiation X-Ray Fluorescence, to a hemi-quantitative interpretation of the growth mode of porphyroblasts. The analysis was done at the Beijing Synchrotron Radiation Facility. The specimens were sampled from metapelite of the Baoyintu Group, northern Urad Middle Banner, Inner Mongolia. The new method is successful for determining the microscopic distribution of trace elements in porphybroblasts. The results support the theory of deformation partition, which has been brought forth by Bell and his colleagues, and demonstrate the existence of porphyroblast growth phases and the growth mode of porphyroblasts by hemi-quantitative mineral chemical analysis. The porphyroblast grows stage by stage in the manner of the distribution of a roseleaf and is controlled by deformation. We call the growth stage of porphyroblast a growth phase. 展开更多
关键词 Synchrotron Radiation X-ray Fluorescence Analysis deformation partition PORPHYROBLAST growth phase Baoyintu Group
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Properties of Ternary One Dimensional Plasma Photomic Crystals for an Obliquely Incident Electromagnetic Wave Considering the Effect of Collisions in Plasma Layers 被引量:2
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作者 S. PRASAD Vivek SINGH A. K. SINGH 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第12期1084-1090,共7页
An analytical study is presented on the modal dispersion characteristics, group velocity, and effective group, as well as the phase index of a ternary one dimensional plasma photonic crystal for an obliquely incident ... An analytical study is presented on the modal dispersion characteristics, group velocity, and effective group, as well as the phase index of a ternary one dimensional plasma photonic crystal for an obliquely incident electromagnetic wave considering the effect of collisions in plasma layers. The dispersion relation is derived by using the transfer matrix method and the boundary conditions based on electromagnetic theory. The dispersion curves are plotted for both the normal photonic band gap structure and the absorption photonic band gap structure. It is found that the increase in the angle of incidence shifts the photonic band gap toward higher frequencies. Also, the cutoff frequency is independent of collisions. 展开更多
关键词 ternary plasma photonic crystal dispersion curves group and phase velocities obliquely incident collision effect
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Review on second-harmonic generation of ultrasonic guided waves in solid media(Ⅰ): Theoretical analyses 被引量:1
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作者 李卫彬 邓明晰 项延训 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第11期51-65,共15页
Considering the high sensitivity of the nonlinear ultrasonic measurement technique and great advantages of the guided wave testing method, the use of nonlinear ultrasonic guided waves provides a promising means for ev... Considering the high sensitivity of the nonlinear ultrasonic measurement technique and great advantages of the guided wave testing method, the use of nonlinear ultrasonic guided waves provides a promising means for evaluating and characterizing the hidden and/or inaccessible damage/degradation in solid media. Increasing attention on the development of the testing method based on nonlinear ultrasonic guided waves is largely attributed to the theoretical advances of nonlinear guided waves propagation in solid media. One of the typical acoustic nonlinear responses is the generation of second harmonics that can be used to effectively evaluate damage/degradation in materials/structures. In this paper, the theoretical progress of second-harmonic generation(SHG) of ultrasonic guided wave propagation in solid media is reviewed. The advances and developments of theoretical investigations on the effect of SHG of ultrasonic guided wave propagation in different structures are addressed. Some obscure understandings and the ideas in dispute are also discussed. 展开更多
关键词 second-harmonic generation(SHG) ultrasonic guided waves cumulative growth effect phase and group velocity matching
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Investigation of Radio Ray-Path and Electron Density Slope of the Ionosphere
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作者 Chong Yanwen Huang Tianxi +2 位作者 Jiang Liu Wang Xinmiao Sandro M. Radicella(College of Electronic Information, Wuhan University, Wuhan 430072, China)(College of Computer Science and Application, Wuhan University, Wuhan 430072, China)(International Center for Th 《Wuhan University Journal of Natural Sciences》 CAS 1998年第4期449-452,共4页
The three dimensional ray-path equation considering the effect of the horizontal gradient of the ionospheric electron density is obtained. By integrating in upgoing and downgoing stage, the point on the raypath can be... The three dimensional ray-path equation considering the effect of the horizontal gradient of the ionospheric electron density is obtained. By integrating in upgoing and downgoing stage, the point on the raypath can be determined and the propagation channel in HF radio telecommunication may be recknoed and predicted. Considering the effect of the electron density slope the ray-path is asymmetric about the reflecting point, and the wave is no longer in the great circle determined by the original wave vector. The group path and the phase path can also be solved. 展开更多
关键词 ionospheric slope IONOSPHERE ray-path equation phase path and group path
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Gravity Wave Generated by Initial Axisymmetric Disturbance at the Surface of an Ice‑covered Ocean with Porous Bed
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作者 Piyali Kundu Rumpa Chakraborty 《Journal of Marine Science and Application》 CSCD 2021年第4期632-645,共14页
This paper is concerned with the generation of gravity waves due to prescribed initial axisymmetric disturbances created at the surface of an ice sheet covering the ocean with a porous bottom.The ice cover is modeled ... This paper is concerned with the generation of gravity waves due to prescribed initial axisymmetric disturbances created at the surface of an ice sheet covering the ocean with a porous bottom.The ice cover is modeled as a thin elastic plate,and the bottom porosity is described by a real parameter.Using linear theory,the problem is formulated as an initial value problem for the velocity potential describing the motion.In the mathematical analysis,the Laplace and Hankel transform techniques have been used to obtain the depression of the ice-covered surface in the form of a multiple infnite integral.This integral is evaluated asymptotically by the method of stationary phase twice for a long time and a large distance from the origin.Simple numerical computations are performed to illustrate the efect of the ice-covered surface and bottom porosity on the surface elevation,phase velocity,and group velocity of the surface gravity waves.Mainly the far-feld behavior of the progressive waves is observed in two diferent cases,namely initial depression and an impulse concentrated at the origin.From graphical representations,it is clearly visible that the presence of ice cover and a porous bottom decreases the wave amplitude.Due to the porous bottom,the amplitude of phase velocity decreases,whereas the amplitude of group velocity increases. 展开更多
关键词 Axisymmetric disturbances and ice-covered ocean Porous bottom Laplace and Hankel transform Method of stationary phase Free surface depression phase velocity and group velocity
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A NEW POLYMER-BOUND 1,2-DIOL AS A PROTECTING AGENT FOR SYMMETRICAL DIALDEHYDE
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作者 任启生 黄文强 +1 位作者 赵芬芝 何炳林 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1989年第4期346-353,共8页
A novel polymer-bound 1,2-diol, 3-polystyrylsulfonyl-1,2-propanediol (6) had been prepared by the reaction of sodium polystyrylsulfinate with allyl bromide, followed by oxidation and. hydrolysis or directly with 3-chl... A novel polymer-bound 1,2-diol, 3-polystyrylsulfonyl-1,2-propanediol (6) had been prepared by the reaction of sodium polystyrylsulfinate with allyl bromide, followed by oxidation and. hydrolysis or directly with 3-chloro-1,2-propanediol in the presence of a phase transfer catalyst, n-tetrabutylammonium iodide. The capacity of resin 6 for terephthaidehyde reached 1.43 mmol/g. The aldehydic groups attached to polymer 6 reacted with hydroxylamine hydrochloride or reduced by sodium borohydride giving p-formylbenzaldoxime (yield: 89%)and p-formyl-benzalcohol (yield: 734%), respectively. The high yields of these polymer-supported reactions showed that the polymer 6 possessed the effective isolation of its reactive sites. 展开更多
关键词 3-polystyrylsulfonyl-1 2 - propanediol polymer-supported protecting group solid - phase organic synthesis cleavage of aldol linkages
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Phase group synchronization between any signals and its physical characteristics 被引量:2
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作者 DU BaoQiang SHI LinLin +4 位作者 CHEN YaoMing DONG ShaoFeng YANG ZhiGang CAO LingZhi GUO ShuTing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第4期674-679,共6页
The phase group synchronization between any signals is further revealed,which is based on proposing the new concepts of the greatest common factor frequency,the least common multiple period,quantized phase shift resol... The phase group synchronization between any signals is further revealed,which is based on proposing the new concepts of the greatest common factor frequency,the least common multiple period,quantized phase shift resolution,equivalent phase comparison frequency and so on.Then the problem of phase comparison and processing between different frequency signals is solved and shown in detail.Using the basic principle and the variation law of group phase difference,the frequency stability better than 10-14/s can be easily obtained in the time&frequency measurement and control domain,and experimental results also show the phase relations between atomic energy level transition signal and the locked crystal oscillator signal in an active hydrogen atomic clock are strict phase group synchronization,and locked precision with 10-13/s can be reached based on phase group synchronization.The phase group synchronization can provide technical support to frequency linking among radio frequency,microwave and light frequency. 展开更多
关键词 equivalent phase comparison frequency least common multiple period group phase difference group period phase processing phase group synchronization
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High-precision time and frequency measurement method combining time-space conversion and different frequency phase detection 被引量:4
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作者 DU BaoQiang WANG YanFeng +3 位作者 CUI GuangZhao GUO ShuTing DONG ShaoFeng LIU Dan 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第11期2110-2115,共6页
According to the time&space conversion relations and different frequency phase detection principle,an ultra-high precision time&frequency measurement method is proposed in this paper.The higher accuracy and st... According to the time&space conversion relations and different frequency phase detection principle,an ultra-high precision time&frequency measurement method is proposed in this paper.The higher accuracy and stability of the speed of light and electromagnetic signals during the transmission in space or a specific medium enable the measurement of short time interval which uses the coincidence detection of signal’s transmission delay in length.The measurement precision better than 10 picoseconds can be easily obtained.The method develops the length vernier utilizing the stability of signal’s transmission delay,minimizes the fuzzy region of phase coincidence between the standard frequency signal and the measured signal,approaches the best phase coincidences and therefore improves the measurement precision which is higher than the precision provided by the traditional methods based on frequency processing.Besides,the method costs less than the traditional methods and can also solve the problem of the measurement of super-high frequency.Experimental results show the method can improve the measurement precision to 10 12/s in the time&frequency domain. 展开更多
关键词 time and space conversion delay-time phase shift different phase coincidence detection group phase difference
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Enantiomeric separations of four basic drugs containing N-alkyl groups by a RP-HPLC system using SBE-β-CD as chiral mobile phase additive 被引量:2
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作者 Min Huang Wen-Jing Chen +11 位作者 Ying Zhou Ru Feng Jie Fu Jing-Yi Ma Xiang-Shan Tan Chi-Yu He Qi-Ming Zhang Wen-Yi He Yu-Lin Deng Yu-Kui Zhang Xian-Feng Zhang Yan Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第9期840-844,共5页
The chiral separations of four pharmaceutical racemates which contain N-alkyl groups were satisfactorily resolved using SBE-β-CD as a chiral mobile phase additive (CMPA) in a RP-HPLC system (the resolution is 2.70... The chiral separations of four pharmaceutical racemates which contain N-alkyl groups were satisfactorily resolved using SBE-β-CD as a chiral mobile phase additive (CMPA) in a RP-HPLC system (the resolution is 2.701 for ondansetron hydrochloride, 1.996 for sulpiride, 1.293 for clenbuterol hydrochloride and 0.816 for omeprazole). In addition, the effects of different parameters such as CD type and CD concentration were investigated. The separation mechanism arises through the combination of several potential interactions, including electrostatic interactions as well as hydrogen bonding interactions and hydrophobic inclusion interactions, which allow for the SBE-β-CD-drug complexation with strong stereoselectivity and stability. The resolution also relates to the number and location of N atoms in the enantiomers. This method will be applicable to the isolation of various types of biologically imoortant enantiomers containing N-alkyl groups. 展开更多
关键词 Chiral separation Chiral mobile phase additive (CMPA)SBE-β-CDN-Alkyl group
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Symmetry protected topological Luttinger liquids and the phase transition between them
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作者 Hong-Chen Jiang Zi-Xiang Li +1 位作者 Alexander Seidel Dung-Hai Lee 《Science Bulletin》 SCIE EI CSCD 2018年第12期753-758,共6页
We show that a doped spin-1/2 ladder with antiferromagnetic intra-chain and ferromagnetic inter-chain coupling is a symmetry protected topologically non-trivial Luttinger liquid.Turning on a large easy-plane spin anis... We show that a doped spin-1/2 ladder with antiferromagnetic intra-chain and ferromagnetic inter-chain coupling is a symmetry protected topologically non-trivial Luttinger liquid.Turning on a large easy-plane spin anisotropy drives the system to a topologically-trivial Luttinger liquid.Both phases have full spin gaps and exhibit power-law superconducting pair correlation.The Cooper pair symmetry is singlet dxy in the non-trivial phase and triplet Sz? 0 in the trivial phase.The topologically non-trivial Luttinger liquid exhibits gapless spin excitations in the presence of a boundary,and it has no non-interacting or mean-field theory analog even when the fluctuating phase in the charge sector is pinned.As a function of the strength of spin anisotropy there is a topological phase transition upon which the spin gap closes.We speculate these Luttinger liquids are relevant to the superconductivity in metalized integer spin ladders or chains. 展开更多
关键词 Topological Luttinger liquids Symmetry protected topological phase phase transition Superconductivity Density-matrix renormalization group
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Changes of the acoustic modal phase velocity,group velocity and interference distance in an eddy
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作者 GAO Tianfu CHEN Yaoming(Institute of Acoustics, Academia Sinica Beijing 100080) 《Chinese Journal of Acoustics》 1998年第1期1-13,共13页
Using the modal dispersion equation with the phase-integral approaches, and con-sidering an eddy (or water mass) as a sound channel disturbance, the effects of the undisturbed channel, cold-core eddy and warm-core edd... Using the modal dispersion equation with the phase-integral approaches, and con-sidering an eddy (or water mass) as a sound channel disturbance, the effects of the undisturbed channel, cold-core eddy and warm-core eddy on the acoustic propagation characteristics are dis-cussed. According to the solutions of the dispersion equation, the relation between the modal Parameters (phase velocity, group velocity and interference distance) and the eddy intensity is obtained. When the plane wave (with an incident angle a) travels toward the center of a warm-core eddy (disturbed intensity BM ) 'double channel phenomenon' will take place in case of sin2 α < BM < 2(1 - cosα), and then the modal phase velocity and interference distance will have anomalous changes which are completely different from the case of the cold-core eddy. 展开更多
关键词 Am Changes of the acoustic modal phase velocity group velocity and interference distance in an eddy
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Mintal Group's High-carbon Ferrochrome 350,000-ton Project Phase Ⅲ Starts Construction
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《China Nonferrous Metals Monthly》 2018年第6期5-5,共1页
Recently,Mintal Group commenced construction of a stainless steel base materials project with an annual output of 350,000 tons,marking that the Phase I base material project for the supply of basic raw materials for t... Recently,Mintal Group commenced construction of a stainless steel base materials project with an annual output of 350,000 tons,marking that the Phase I base material project for the supply of basic raw materials for the Mintal’s stainless steel production enters into the implementation phase.This project is also known as Mintal’s high-carbon ferrochrome project phase III with an investment of 900million yuan and occupying an area of 300 mu. 展开更多
关键词 Mintal Group’s High-carbon Ferrochrome 350 000-ton Project phase Starts Construction
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Tuning the helical twisting power of nematic liquid crystals induced by chiral 1,2-propanediol derivatives using varied substituents 被引量:1
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作者 Hai Quan Zhang An Lei Qin 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第1期37-40,共4页
In this study,a novel series of chiral 1,2-propanediol derivatives with different electron-donating and electron-withdrawing groups were synthesized and characterized by FT-IR and ~1H NMR.The helical twisting properti... In this study,a novel series of chiral 1,2-propanediol derivatives with different electron-donating and electron-withdrawing groups were synthesized and characterized by FT-IR and ~1H NMR.The helical twisting properties of all the chiral dopants were investigated by doping the chiral dopants into a nematic liquid crystal host(SLC-1717).The results indicate that the donor-acceptor electron effect have a prominent influence on helical twisting property of the chiral nematic phase induced by the chiral dopants. Introducing electron-withdrawing groups into the terminal ends of chiral 1,2-propanediol can decrease the absolute values of the helical twisting power.In addition,the helix inversion temperatures of the induced chiral nematic phase are variational with the change of terminal groups. 展开更多
关键词 Chiral dopants Chiral nematic phase Helical twisting power Electron-donating group Electron-withdrawing group
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