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41.
An accurate solution for the three-nucleon bound state is obtained within 1 keV in the binding energy and, on the whole,
better than 1% in the wave function, using a new systematic and efficient method. The method is based on a recently developed
separable expansion for any finite-range interaction, in which a rigorous separable series for the two-body t-matrix is obtained by expanding the wave function in terms of a complete set of basis functions inside the range of the potential.
In order to treat a potential with a strong repulsive core, as in the case of the Argonne potential, we develop a two-potential
formalism. The expansion starts with a few EST (Ernst, Shakin, and Thaler) terms in order to accelerate the convergence and
continues with an orthogonal set of polynomials, avoiding the known difficulties of a pure EST expansion. Thus, several techniques
are combined in the present extended separable expansion (ESE). In this way, the method opens a new systematic treatment for
accurate few-body calculations resulting in a dramatic reduction in the CPU time required to solve few-body equations.
Received November 6, 1996; revised April 14, 1997; accepted for publication April 30, 1997 相似文献
42.
The rich history of prime numbers includes great names such as Euclid, who first analytically studied the prime numbers and proved that there is an infinite number of them, Euler, who introduced the function , Gauss, who estimated the rate at which prime numbers increase, and Riemann, who extended to the complex plane z and conjectured that all nontrivial zeros are in the axis. The nonadditive entropy , where BG stands for Boltzmann-Gibbs) on which nonextensive statistical mechanics is based, involves the function . It is already known that this function paves the way for the emergence of a q-generalized algebra, using q-numbers defined as , which recover the number x for . The q-prime numbers are then defined as the q-natural numbers , where n is a prime number We show that, for any value of q, infinitely many q-prime numbers exist; for they diverge for increasing prime number, whereas they converge for ; the standard prime numbers are recovered for . For , we generalize the function as follows: (). We show that this function appears to diverge at , . Also, we alternatively define, for , and , which, for , generically satisfy , in variance with the case, where of course . 相似文献
43.
NMR and DFT studies on persistent carbocations derived from benzo[kl]xanthene,dibenzo[d,d′]benzo[1,2‐b:4,3‐b′]difuran,and dibenzo[d,d′]benzo[1,2‐b:4,5‐b′]difuran in superacidic media 下载免费PDF全文
Takao Okazaki Madoka Nakagawa Takeshi Futemma Toshikazu Kitagawa 《Journal of Physical Organic Chemistry》2016,29(2):107-111
Persistent carbocations generated by the protonation of hetero‐polycyclic aromatic compounds with oxygen atom(s) were studied by experimental NMR and density function theory calculations. Benzo[kl]xanthene ( 1 ), dibenzo[d,d′]benzo[1,2‐b:4,3‐b′]difuran ( 2 ), and dibenzo[d,d′]benzo[1,2‐b:4,5‐b′]difuran ( 3 ) were synthesized by the annulation of arenediazonium salts. Compound 1 in FSO3H‐SbF5 (4:1)/SO2ClF and 3 in FSO3H‐SbF5 (1:1)/SO2ClF ionized to 1aH+ with protonation at C(4) and to 3aH+ with protonation at C(6), and these cations were successfully observed by NMR at low temperatures. The density function theory calculations indicated that 1aH+ and 3aH+ were the most stable protonated carbocations and that 2 should ionize to 2aH+ with protonation at C(6). According to the changes in 13C chemical shifts (Δδ13C), the positive charge was delocalized into the naphthalene unit for 1aH+ , into one benzo[b,d]furan unit for 2aH+ , and into one benzo[b,d]furan unit for 3aH+ . Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
44.
We have been studying various types of computer-generated holograms for three-dimensional (3D) displays both for a real-time holographic video display and a hard copy, or a printed hologram. For the hard copy output, we have developed a direct fringe printer, which is achieved to print over 100 gigapixels computer-generated hologram with 0.44μm pitch. In this paper, we introduce our recent progresses on the rainbow hologram, the cylindrical holograms, and the disk hologram for 3D display. 相似文献
45.
The formation of a deeply-bound K?? –? pp state by the 3He(in-flight K? –, n) reaction is investigated theoretically in a distorted-wave impulse approximation using the Green’s function method. The expected inclusive and semi-exclusive spectra at $p_{K^-} = 1.0$ GeV/c and $\theta_n = 0^{\circ}$ are calculated for the forthcoming J-PARC E15 experiment. We discuss these spectra with some K? –-“pp” optical potentials, taking into account the energy-dependence of the imaginary part of the potentials by a phase space suppression factor. 相似文献
46.
Takeshi Murashige Hideo Fujikake Hiroto Sato Hiroshi Kikuchi Taiichiro Kurita Fumio Sato 《Optical Review》2004,11(6):349-352
We have confirmed light diffraction of aligned polymer fibers obtained by a phase separation of an anisotropic-phase solution of liquid crystal and polymer. He—Ne laser light passing through the polymer fibers was scattered in the axis vertical to the fibers, and had two peaks of light intensity symmetrical to the center of the transmitting laser spot. The two peaks were found to be caused by light diffraction due to the periodic polymer-fiber dispersion because the peaks corresponded to values calculated by intervals between the fibers. The periodical fiber networks are considered to be formed by anisotropic spinodal decomposition. This effect can be used to measure the dispersion order of the polymer fibers. © 2004 The Optical Society of Japan 相似文献
47.
Preparation of Cu2ZnSnS4 thin films by hybrid sputtering 总被引:2,自引:0,他引:2
Tooru Tanaka Takeshi Nagatomo Mitsuhiro Nishio Akihiro Wakahara Hiroshi Ogawa 《Journal of Physics and Chemistry of Solids》2005,66(11):1978-1981
In order to fabricate Cu2ZnSnS4 thin films, hybrid sputtering system with two sputter sources and two effusion cells is used. The Cu2ZnSnS4 films are fabricated by the sequential deposition of metal elements and annealing in S flux, varying the substrate temperature. The Cu2ZnSnS4 films with stoichiometric composition are obtained at the substrate temperature up to 400 °C, whereas the film composition becomes quite Zn-pool at the substrate temperature above 450 °C. The Cu2ZnSnS4 film shows p-type conductivity, and the optical absorption coefficient and the band gap of the Cu2ZnSnS4 film prepared in this experiment are suitable for fabricating a thin film solar cell. 相似文献
48.
We use angle-resolved photoemission spectroscopy to investigate the energy gap(s) in (Bi,Pb)2(Sr,La)2CuO6+delta. We find that the spectral gap has two components in the superconducting state: a superconducting gap and pseudogap. Differences in their momentum and temperature dependence suggest that they represent two separate energy scales. Spectra near the node reveal a sharp peak with a small gap below T(c) that closes at T(c). Near the antinode, spectra are broad with a large energy gap of approximately 40 meV above and below T(c). The latter spectral shape and gap magnitude are almost constant across T(c), indicating that the pseudogap state coexists with the superconducting state below T(c), and it dominates spectra around the antinode. We speculate that the pseudogap state competes with the superconductivity by diminishing spectral weight in antinodal regions, where the superconducting gap is largest. 相似文献
49.
Asobe M Tadanaga O Umeki T Yanagawa T Nishida Y Magari K Suzuki H 《Optics letters》2007,32(23):3388-3390
We propose a novel quasi-phase-matched (QPM) device that can generate unequally spaced multiple wavelengths. Unequally spaced multiple QPM peaks can be obtained by employing the optimized phase modulation of a periodic domain structure. We fabricated a LiNbO3 waveguide device for 3.2-3.4 microm band difference frequency generation based on the design. Using the multiple mid-infrared outputs, we demonstrate the detection of multiple hydrocarbon gases, namely, methane, ethylene, and ethane. 相似文献
50.
Doppler-broadened atomic and molecular spectra were observed with a one octave tunable, continuous-wave, doubly resonant, monolithic optical parametric oscillator (OPO) using 5% MgO-doped LiNbO3 as a non-linear crystal with a birefringent phase-matching configuration. By tuning the frequency of a pump laser, longitudinal mode selection over 20 successive modes, corresponding to a 60 GHz span, was possible, owing to the simple structure of the monolithic OPO. Continuous frequency tuning was achieved using an external waveguide-type electrooptic phase modulator (EOM). By changing the modulation frequency of the EOM, frequency tuning of the optical sidebands over 12 GHz was possible, which is larger than the one free spectral range of the monolithic cavity of 3 GHz. We could observe the Cs-D1 (894 nm), Cs-D2 (852 nm), Rb-D1 (795 nm), acetylene R9 (1520 nm) and P9 (1530 nm) transitions with the single monolithic OPO. 相似文献