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991.
本文在多通道量子数亏损理论(MQDT)框架下,利用相对论多通道理论(RMCT),分别在冻结实近似、 考虑Δl=-1的偶极极化效应、Δl=+1的偶极极化效应、Δl=± 1的偶极极化效应、伸缩模效应以及同时考虑偶极极化效应和伸缩模效应等不同层次近似下,系统地计算了碱金属Li, Na, K, Rb, Cs和Fr七个里德伯系列的能级,即ns2S1/2, np2P1/2, np2P3/2, nd2D3/2, nd2D5/2, nf2F5/2 和nf2F7/2.计算结果表明,电子关联效应对碱金属原子的里德伯能级的影响很大.总的来说,偶极极化效应比伸缩模效应重要,而在偶极极化效应中, Δl = + 1的偶极极化效应比Δl = - 1的偶极极化效应重要.但对于Na的ns2S1/2,(nd2D3/2,nd2D5/2)里德伯系列的能级,和Li的(np2P1/2,np2P3/2)里德伯系列的能级,是伸缩模效应比较重要. 相似文献
992.
Shuai Wang Yongfeng Ruan Taiju Tsuboi Shouchao Zhang Youfa Wang Zhouli Wu Hongshuang Tong 《Crystal Research and Technology》2012,47(9):928-938
The BaY2F8 crystals doped with different concentrations of Tm3+ ions were prepared by the temperature gradient technique (TGT). X‐ray powder diffraction was applied to analyze the phase. The cracking phenomenon along (010) and (100) planes of the crystals grown by temperature gradient technique was studied on the basis of the structure of BaY2F8 crystals. The absorption spectra were measured and investigated in the ultraviolet‐visible and near‐infrared ranges at room temperature. Several characteristic absorption bands of Tm3+‐doped BaY2F8 crystal were observed. The emission and excitation spectra were obtained and investigated at room temperature and 12 K, showing the characteristic emission peaks of Tm3+ ions. The temperature dependence of Photoluminescence curve was also investigated in the range of 12–296 K. The luminescence intensity of emission bands decreased with increasing temperature, while the effective bandwidth increased. The up‐conversion spectrum excited at 650 nm was recorded and up‐conversion mechanism was analyzed in detail. The result showed the purple, green and yellow emissions corresponding to 3P1→3F3, 1D2→3H5 and 3P0→1G4 transitions, respectively. 相似文献
993.
994.
We compute the recently introduced Fan–Jarvis–Ruan–Witten theory of W-curves in genus zero for quintic polynomials in five variables and we show that it matches the Gromov–Witten genus-zero theory
of the quintic three-fold via a symplectic transformation. More specifically, we show that the J-function encoding the Fan–Jarvis–Ruan–Witten theory on the A-side equals via a mirror map the I-function embodying the period integrals at the Gepner point on the B-side. This identification inscribes the physical Landau–Ginzburg/Calabi–Yau
correspondence within the enumerative geometry of moduli of curves, matches the genus-zero invariants computed by the physicists
Huang, Klemm, and Quackenbush at the Gepner point, and yields via Givental’s quantization a prediction on the relation between
the full higher genus potential of the quintic three-fold and that of Fan–Jarvis–Ruan–Witten theory. 相似文献
995.
Zhuoping Ruan 《Journal of Mathematical Analysis and Applications》2010,367(2):625-639
In this paper, we use the idea of the discrete Littlewood-Paley theory developed by Han and Lu to carry out the three-parameter weighted Hardy spaces theory under a rather weak condition on the product weight (w∈A∞) and obtain the boundedness of singular integral operators on the weighted Hardy spaces. 相似文献
996.
Let Mn be the algebra of all n×n matrices, and let φ:Mn→Mn be a linear mapping. We say that φ is a multiplicative mapping at G if φ(ST)=φ(S)φ(T) for any S,T∈Mn with ST=G. Fix G∈Mn, we say that G is an all-multiplicative point if every multiplicative linear bijection φ at G with φ(In)=In is a multiplicative mapping in Mn, where In is the unit matrix in Mn. We mainly show in this paper the following two results: (1) If G∈Mn with detG=0, then G is an all-multiplicative point in Mn; (2) If φ is an multiplicative mapping at In, then there exists an invertible matrix P∈Mn such that either φ(S)=PSP-1 for any S∈Mn or φ(T)=PTtrP-1 for any T∈Mn. 相似文献
997.
Haoyu Jiang Zengqi Cui Yiwei Hu Jie Liu Haofan Bai Jinxiang Chen Guohui Zhang Yu.M.Gledenov E.Sansarbayar G.Khuukhenkhuu L.Krupa I.Chuprakov Xichao Ruan Hanxiong Huang Jie Ren Qiwen Fan 《中国物理C(英文版)》2022,(2):70-78
Cross sections of the 58,60,61Ni(n,α)55,57,58Fe reactions were measured at 8.50,9.50 and 10.50 MeV neut-ron energies based on the HI-13 tandem accelerator of Ch... 相似文献
998.
<正>Elastic behavior of 4-branched star polymer chain with different chain length N adsorbed on attractive surface is investigated using steered molecular dynamics(SMD) simulation method based on the united-atom(UA) model for branched alkanes.The simulation is realized by pulling up the chain via a linear spring with a constant velocity v = 0.005 nm/ps.At the beginning,the chain lies extensionally on adsorbed surface and suffers continuous deformations during the tensile process.Statistical parameters as mean-square radii of gyration S~2_(xy),S~2_z,shape factor δ,describing the conformational changes,sectional density den which gives the states of the chain,and average surface attractive energy U_a,average total energy U,average force f probed by the spring,which characterize the thermodynamic properties, are calculated in the stimulant process.Remarkably,distinguishing from the case in linear chains that there only exists one long plateau in the curve of f,the force plateau in our study for star chains is multiple,denoting different steps of desorption,and this agrees well with the experimental results in essence.We find during the tensile process,there are three characteristic distances Z_c,Z_t and Z_0 from the attractive surface,and these values vary with N.When Z=Z_c,the chain is stripped from the surface,but due to the form of wall-monomer interaction,the surface retains weak influence on the chain till Z = Z_c.From Z=Z_t,parameters U_a,U and f respectively reach a stable value,while the shape and the size of the chain still need adjustments after Z_t till Z_0 to reach their equilibrium states.Specifically,for short chain of N= 41,Z_t and Z_0 are incorporated.These results may help us to deepen the knowledge about the elastic behavior of adsorbed star polymer chains. 相似文献
999.
Ruan Yongfeng Zhang Shouchao Li Guanghui Zhu Wei Wang Danli Zhang Lingcui 《Crystal Research and Technology》2010,45(5):562-566
Single crystals of Erbium (Er) doped BaY2F8 have been obtained by the temperature gradient technique (TGT). No‐seed‐grown crystal of Er:BaY2F8, with the dimensions up to several centimeters, was obtained by self‐crystallization. The optimizations of various growth parameters were systemically investigated. The results indicated that the temperature gradient of 6‐7 K/mm and the cooling velocity less than 6 K/h were suitable for the crystal growth. The XRD data and the investigations on the growth striations by a stereo polarization microscope displayed that the [001] direction is the dominating direction for the crystal growth. The crystal grown by TGT often cracks along with the (100) plane, which is caused by the excessive decrease of the temperature during the crystal growth, for there is a rapid change in the thermal expansion curve of the BaY2F8 crystal in the temperature range from 800 °C to 900 °C. The spectral properties of Er:BaY2F8 single crystals have been studied and the effects of frequency up‐conversion of the crystals are reported. Spectral data suggest that the quality of Er:BaY2F8 crystal obtained by TGT method is good and the crystal has the potential application in laser devices. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
1000.
从Grüner的非线性方程出发,克服了原作者略去二阶微分项所带来的理论缺陷.依据稳定周期解的结果,推出了单段CDW的启动电场的阈值和各分段的滑行速度与外场成正比的关系,揭示出单段CDW遵循欧姆定律是Grüner非线性方程的固有性质.并将此结果用于多分段模型,最终导出CDW非线性电导的指数律和阈场,它们与实验公式一致,同时也说明了窄带噪声的来源.还就多分段的串联问题,提出了“弹性连接”机理的内力处理方法,得到了更为理想的结果.
关键词:
CDW
非线性电导
指数律
强作用杂质
弱作用杂质
弹性连接 相似文献