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1993年, 第2卷, 第12期　刊出日期：1993-12-20 上一期    下一期

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AXISYMMETRIC AND NONAXISYMMETRIC TOROIDAL VESICLE MEMBRANES 谢毓章, 欧阳钟灿 1993 (12):  881-889.  doi: 10.1088/1004-423X/2/12/001 摘要 ( 1523 )   PDF(190KB) ( 429 )   In this report we are going to show that the parametric equation of the Clifford torus used in the brief report, Phys. Rev. A41(1900), 4517, is in consistency with the parametric equation of the Dupin cyclide under the condition c = 0 used in the brief report, Phys. Rev. E47(1993), 747. The necessary and sufficient conditions for the existence of Dupin cyclide vesicle membrane are derived in this report. 相关文章 | 计量指标

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RECURRENT FORMULA FOR α-ROW PARTITION AND THE CALCULATIONS OF THE MULTIPLICITIES OF COUPLING STATES IN SHELL-MODEL 陈健华, 程香爱, 高一东 1993 (12):  890-897.  doi: 10.1088/1004-423X/2/12/002 摘要 ( 1138 )   PDF(144KB) ( 333 )   In this paper, a recurrent formula for α-row partition is given. Using this formula, we get the multiplicities of all sorts of coupling states in shell-model. It has been proved to be very efficient in simplifying the ealculations concerned. 相关文章 | 计量指标

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THE CRITICAL DYNAMICS OF THE KINETIC ISING MODELS ON THE SYSTEMS WITH Rmin> 2 周健, 陈式刚 1993 (12):  898-906.  doi: 10.1088/1004-423X/2/12/003 摘要 ( 1404 )   PDF(229KB) ( 395 )   We perform the exact TDRG transformations on the kinetic Ising model of the braced ladder whose Rmin is 5. Within our knowledge, this is the only example that the exact TDRG transformations have been performed on a system with Rmin >2. We show that under Achiam's linear response theory there must be important excitations of the multi-spin operators in the kinetic Ising models of the systems with Rmin > 2, the dynamic critical behaviours of the systems are greatly affected by these excitations. Moreover, we get the conclusion that for the kinetic Ising models of the systems with Rmin=∞ exact TDRG calculationa are impossible. The complete new and interesting results are given. 相关文章 | 计量指标

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THE PRODUCTION AND CHARACTERISTICS OF THE SLOSHING ELECTRONS IN A MAGNETIC MIRROR 张建德, 方瑜德, 任兆杏, 邱励俭 1993 (12):  907-916.  doi: 10.1088/1004-423X/2/12/004 摘要 ( 1241 )   PDF(235KB) ( 405 )   The experiment on the formation of sloshing electrons by electron cyclotron resonance heating in a magnetic mirror is described, and the physical properties of them are investigated. The results show that (1) the sloshing electron configuration is formed, and its characteristics are very different from those of the hot electron ring; (2) Rn, the hot electron density ratio which represents the sloshing electron configuration, decreases as the mirror magnetic field increases, and the maximum of Rn can reach about 2.65. 相关文章 | 计量指标

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NEW AUTOIONIZING STATES NEAR THE FIRST IONIZATION LIMIT OF RARE EARTH ELEMENT Dy 周海军, 许祥源, 黄雯, 陈瓞延 1993 (12):  917-924.  doi: 10.1088/1004-423X/2/12/005 摘要 ( 1119 )   PDF(165KB) ( 584 )   This paper describes the investigation of autoionizing states near the first ionization limit of rare-earth element Dy. The 62, 51, 97 and 25 new autoionizing states resulting from the states of 4f10(5I8)6s6p(3P02)3I07, 4f9 (6H0)5d2(3F)(8G0)6s9G07, 4f9(6F0)5d6s2 7H07 and 4f95d6s2 7K07, respectively, were found by using a laser resonance ionization time-of-flight mass spectrometer (LRI-TOFMS), The photoionization efficiencies for different channels were compared with each other. In addition, the Shore-Fano parameters of autoionizing states were determined by a nonlinear fitting program. 相关文章 | 计量指标

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A STUDY ON SURFACE-ENHANCED HYPER-RAMAN SCATTERING OF BASIC FUCHSIN ADSORBED ON THE SILVER COLLOID 潘多海, 张鹏翔, 李祥生, 苗润才, 郇宜贤 1993 (12):  925-929.  doi: 10.1088/1004-423X/2/12/006 摘要 ( 1185 )   PDF(162KB) ( 403 )   This paper presents the surface-enhanced hyper-Raman scattering (SEHRS) effect of basic fuchsin (BF) adsorbed on the silver colloid. On the basis of the absorption spectra, a new absorption band at 1000nm has been observed in the case of BF adsorption on the silver colloid, The result indicates that surface electromagnetic enhancement also appears at the incident photon frequency in the near-IR region, which plays an important role in the SEHRS signals. The electromagnetic enhancement factor (2.0×l04) is estimated by using electromagnetic model. Additionally, surface-enhanced second-harmonic generation (SHG) effect in the cases of pure silver colloid, silver colloid plus adsorbed molecule and KCl solution has been detected. 相关文章 | 计量指标

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THERMOELECTRIC POWER IN (Gd, Sm)1.85Ce0.15CuO4 SYSTEM 刘国良, 林征, 林勤, 张玉芬, 蒋连化, 李国红, 阎守胜 1993 (12):  930-936.  doi: 10.1088/1004-423X/2/12/007 摘要 ( 1276 )   PDF(206KB) ( 405 )   Thermoelectric power measurements are reported for seven samples with different x in the Gd1.85-xSmxCe0.15CuO4 system at temperatures ranging from 80K to 300K. For Sm-rich superconducting samples, thermoelectric power S has a small negative value and is almost temperature independent. As the content of Sm decreases, the absolute value of S increases and a broad valley appears in the S(T) curve. The results which can be interpreted in terms of a two-channel model support the existence of mid-gap states with Fermi level close to the minimum of the density of states as well as the coexistence of electron and hole carriers. It is suggested that a linear temperature dependence of S with a small negative slope is close to the intrinsic behavior in the a-b plane of normal states for superconducting samples. 相关文章 | 计量指标

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INTERNAL FRICTION AND ULTRASONIC ATTENUATION RELATED TO CARRIERS IN HIGH Tc SUPERCONDUCTORS 黄以能, 王业宁, 陈沙鸥, 周海龙, 张清明, 沈惠敏, 杨震, 赵忠贤, 刘鹏, 张进龙, 司卫东, 曹国辉 1993 (12):  937-946.  doi: 10.1088/1004-423X/2/12/008 摘要 ( 1643 )   PDF(281KB) ( 434 )   For both BiSrCaCuO and TlBaCaCuO samples, internal frictions (Q-1) in the kHz range reveal a plateau (Q-1p) above Tc and a rapid drop below Tc with the turning points located just at Tc for various samples with different Tc. This anomaly cannot be observed in non-superconducting samples. The ultrasonic attenuation (α) in TlBaCaCuO displays similar results to the internal friction. Moreover, it is discovered that the Q-1p is nearly proportional to the carrier density for Y(Pr)BaCuO and Gd(Pr)BaCuO with different Pr contents. These results show that the drop of Q-1 and a below Tc is closely related to superconducting condensation. The Q-1p and αp can be explained using coupling-model of carriers with local dynamic distortion because high Tc superconductors are strong-correlation systems. Furthermore, by taking account of the smearing of superconducting gap structure resulting from the recombination of quasi-particles and by modifying the BCS relative jump rate as S(E, E', Γ) = Re{1-Δ2/[(E-iΓ)(E'-iΓ)]}, the calculated results of internal friction and ultrasonic attenuation below Tc are in good agreement with the experimental data. The superconducting gap Δ and the damping rate Γ for both BiSrCaCuO and TlBaCaCuO have also been obtained, they are in accordance with those got by tunneling spectrum and NMR methods, etc. 相关文章 | 计量指标