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71.
Energy spectra for decaying 2D turbulence in a bounded domain 总被引:1,自引:0,他引:1
We use results derived in the framework of the replica approach to study the liquid-glass thermodynamic transition. The main results are derived without using replicas and applied to the study of the Lennard-Jones binary mixture introduced by Kob and Andersen. We find that there is a phase transition due to the entropy crisis. We compute both analytically and numerically the value of the phase transition point T(K) and the specific heat in the low temperature phase. 相似文献
72.
Consider a large collection of elastic rectangular plates with random inhomogeneities, but otherwise indistinguishable in any overall sense. An expression is obtained for the natural frequency, μ, of such plates, vibrating freely under simply supported boundary conditions, in the form μ = μ(0) + ?μ(1) + ?2μ(2) + … where μ(0) is the natural frequency of a homogeneous comparison plate, ? is a small real parameter measuring the degree of inhomogeneity, and the coefficients μ(1), μ(2), …, are given explicitly. By constructing geometrically a correlation function for a special type of composite plate, μ(1) is computed and hence, to first order in ?, the variance of μ. The paper concludes with a theorem linking the mean and variance of μ to the volume concentration and geometry of the inclusions in the plate. 相似文献
73.
74.
75.
Akhtaruzzaman M Tomura M Zaman MB Nishida J Yamashita Y 《The Journal of organic chemistry》2002,67(22):7813-7818
Three novel 4,7-bis(n-pyridylethynyl)-2,1,3-benzothiadiazoles (n = 2, 3, and 4) were synthesized by using the Sonogashira cross-coupling reaction of 4,7-dibromo-2,1,3-benzothiadiazole with the corresponding ethynylpyridines in the presence of a Pd(II) catalyst. The viologen analogues were also prepared by methylation of pyridyl nitrogen atoms. X-ray structure analysis of these compounds revealed the linear molecular structures with unusual columnar crystal structures. Insertion of a benzothiadiazole moiety into the acetylene-pyridine skeleton brings about a large increase in electron affinity and the bispyridyl compounds obtained here show high fluorescence quantum yields. 相似文献
76.
M. K. Suleymanov R. G. Nazmitdinov E. I. Shahaliev O. B. Abdinov A. Ajaz A. Zaman K. H. Khan Z. Wazir 《Bulletin of the Russian Academy of Sciences: Physics》2012,76(10):1089-1092
A new statistical method is proposed for the analysis of experimental data obtained in nucleus-nucleus collisions at high energies which borrows from ideas developed using the Random Matrix Theory. The method allows us to detect regions with correlation effects in the momentum distributions of secondary particles. 相似文献
77.
78.
Haladhara Naik Guinyun Kim Kwangsoo Kim Muhammad Zaman Sung-Chul Yang Muhammad Sahid Manwoo Lee Sung-Gyun Shin Ashok Goswami Moo-Hyun Cho 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(3):1121-1130
The independent isomeric yield ratios of 95m,gNb from the natMo(γ, pxn) reactions with bremsstrahlung end-point energies of 45, 50, 55, 60, and 70 MeV were determined by an activation and an off-line γ-ray spectrometric technique at the Pohang accelerator laboratory (PAL), Korea. The isomeric yield ratios of 95m,gNb from the natZr(p, xn) reactions were also determined in eight different proton energies within 19.4–44.7 MeV by a stacked-foil activation and an off-line γ-ray spectrometric technique using the MC-50 cyclotron of Korea Institute of Radiological and Medical Sciences (KIRAMS), Korea. The measured isomeric yield ratios of 95m,gNb from the present work and the literature data in the natMo(γ, pxn) and natZr(p, xn) reactions were compared with the similar literature data in the natMo(p, αxn) reactions. It was found that the isomeric yield ratio of 95m,gNb increases with projectile energy, which indicate the effect of excitation energy. However, at the same excitation energy, the isomeric yield ratios of 95m,gNb in the natZr(p, xn) and natMo(p, αxn) reactions are higher than those in the natMo(γ, pxn) reaction, which indicates the role of input angular momentum. The isomeric yield ratios of 95m,gNb in the natMo(γ, pxn), natZr(p, xn), and natMo(p, αxn) reactions were also calculated using computer code TALYS 1.4. The calculated isomeric yield ratios of 95m,gNb from three reactions increase with excitation energy. However, in all the three reactions, the calculated values are significantly higher than the experimental data. 相似文献
79.
Summary A point source at an interface between a homogeneous layer of finite depth and an inhomogeneous half-space is considered.
The transmitted wave and the dispersion relation for the Love waves is calculated analytically.
The authors of this paper have agreed to not receive the proofs for correction. 相似文献
80.
Two new pyranoisoflavones, auriculasin and isoauriculasin were isolated from M. auriculata and assigned structures 1 and 3 respectively. The structure assigned earlier to isoauriculatin has been revised to 4. 相似文献