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91.
R. Alexandre Y. Morimoto S. Ukai C. -J. Xu T. Yang 《Communications in Mathematical Physics》2011,304(2):513-581
We prove the global existence and uniqueness of classical solutions around an equilibrium to the Boltzmann equation without
angular cutoff in some Sobolev spaces. In addition, the solutions thus obtained are shown to be non-negative and C
∞ in all variables for any positive time. In this paper, we study the Maxwellian molecule type collision operator with mild
singularity. One of the key observations is the introduction of a new important norm related to the singular behavior of the
cross section in the collision operator. This norm captures the essential properties of the singularity and yields precisely
the dissipation of the linearized collision operator through the celebrated H-theorem. 相似文献
92.
The stable (lower enthalpy) molecular configurations of propionic, butyric, Jeric and lauric acids in the crystalline state have been examined via their atom-atom potentials. It was found that the cis configuration is more stable than the trans configuration for propionic, butyric and valeric acids, and that the trans configuration is more stable than the cis configuration for lauric acid, in accord with a previous IR spectral analysis. The potential energy of benzoic acid was recalculated using the positions of atoms given by Speakman, and indicates that the A form is more stable than the B form, in agreement with the results of previous work. 相似文献
93.
Masaji Shimazu Junzo Tanaka Kunitaka Muramatsu Masayuki Tsukioka 《Journal of solid state chemistry》1980,35(3):402-406
The ferroelectric phase transition in the family LaxBi4?xTi3O12 was investigated by X-ray diffractometry and differential scanning calorimetry. The crystal symmetry is orthorhombic in the range of 1 > x ≥ 0 and tetragonal in x ? 1. It was found that the shift of the phase-transition temperature is closely related to crystallographic symmetry and lattice distortion. (1) As the value of x increases, the ratio of lattice parameters, , decreases toward 1. (2) In the range of 1 > x ≥ 0, the lattice distortion increases with increasing x; just before x exceeds about 1, the distortion reaches a maximum. (3) As x exceeds about 1, the distortion decreases distinctively. (4) In the orthorhombic region, the phase-transition temperature decreases with increasing x. (5) In the tetragonal region, the transition does not occur. (6) The relation of transition temperature Tc to x is represented by a nonlinear function. 相似文献
94.
H. Takahashi S. Ohtsuka T. Ukai N. Mori 《Journal of magnetism and magnetic materials》1987,70(1-3):189-190
The experimental result of the orbital and spin moments for Co in YCo5 is analyzed by the use of the approximate d bands for YCo5. The calculation of the anistropy constants Ku1 and Ku2 is worked out. Finally, the contributions to the anistropy constants due to 3d bands of CoI, those of CoII, those of CoI and CoII, and 3d and 4d bands of CoI, CoII and Y are discussed. 相似文献
95.
A sonic boom signature with a long rise time has the ability to reduce the sonic boom, but it does not necessarily minimize the sonic boom at the ground level because of the real atmospheric turbulence. In this study, an effect of the turbulence on a long rise-time pressure signature was experimentally investigated in a ballistic range facility. To compare the effects of the turbulence on the long and short rise-time pressure signatures, a cone-cylinder projectile that simultaneously produces these pressure signatures was designed. The pressure waves interacted with a turbulent field generated by a circular nozzle. The turbulence effects were evaluated using flow diagnostic techniques: high-speed schlieren photography, a point-diffraction interferometer, and a pressure measurement. In spite of the fact that the long and short rise-time pressure signatures simultaneously travel through the turbulent field, the turbulence effects do not give the same contribution to these overpressures. Regarding the long rise-time pressure signature, the overpressure fluctuation due to the turbulence interaction is almost uniform, and a standard deviation 1.5 times greater than that of the no-turbulence case is observed. By contrast, a short rise-time pressure signature which passed through the same turbulent field is strongly affected by the turbulence. A standard deviation increases by a factor of 14 because of the turbulence interaction. Additionally, there is a non-correlation between the overpressure fluctuations of the long and short rise-time pressure signatures. These results deduce that the length of the rise time is important to the turbulence effects such as the shock focusing/diffracting. 相似文献
96.
Weifang Wang Taiko Oda Remy E.P. Mangindaan Kazuyo Ukai Michio Namikoshi 《Tetrahedron》2007,63(2):409-412
Three new sulfur-containing alkaloids, polycarpaurines A (1), B (2), and C (3) were isolated from the tropical ascidian Polycarpa aurata collected in Indonesia, together with six known compounds (4-9). The structures of new compounds were assigned on the basis of their spectral data. Compounds 1, 3, 4, and 8 inhibited colony formation of Chinese hamster V79 cells with EC50 values of 6.8, 8.6, 3.8, and 10 μM, respectively. Compounds 2 and 7 showed modest activity against V79 cells (EC50>10 μM). 相似文献
97.
Junzo Hirano 《Tetrahedron letters》2007,48(28):4861-4864
A new fluorescent chemosensor, 1,10-phenanthroline-4,7-dione (1), which is capable of the ratiometric sensing of anions in aqueous MeCN, was developed. Chemosensor 1 recognized an anion via two NH groups in the molecule, and showed a much higher affinity for F− than that of 4-quinolone, which binds to an anion at one NH group of the molecule. Upon binding to F−, the intensity of the emission band ascribed to the complex of 1-F− was drastically enhanced, while the emission intensity of unbound 1 gradually decreased. The changes in these two emission bands enabled the successful ratiometric sensing. 相似文献
98.
[structure: see text]. A novel method for the preparation of hydroxy carboxylic acid derivatives has been developed by O2-oxidation of pi-allylnickel intermediates generated by Ni(0)-mediated coupling of 1,2-dienes with CO2. 相似文献
99.
Hiromi Kameya Hideo Nakamura Mitsuko Ukai Yuhei Shimoyama 《Applied magnetic resonance》2011,40(3):395-404
Using electron spin resonance (ESR) spectroscopy, we revealed the irradiation-induced radicals in cellulose and starch. Before
gamma-ray irradiation, no ESR signals were observed in both the glucose polymers. However, after gamma-ray irradiation, a
singlet at g = 2.0 was observed, and a pair of side signals appeared simultaneously. The side signals were found at the symmetric field
positions at both sides of the singlet signal. The side signals were visible in cellulose but not in starch. The side signals
are found to be a precise indicator for irradiation effects in cellulose. They are originated from neither the peroxide radical
of glucose polymer nor the so-called cellulosic radicals. By the simulation method, we found that the side signals are originated
from a triplet due to a hyperfine interaction with two protons. By the theoretical simulation, we revealed that the signal
undergo the rotational motions rather than rigid limit state (or no motion). 相似文献
100.
Y. Ichikawa H. C. Bhang S. Bufalino H. Ekawa P. Evtoukhovitch A. Feliciello H. Fujioka S. Hasegawa S. Hayakawa R. Honda K. Hosomi K. Imai S. Ishimoto C. W. Joo S. Kanatsuki R. Kiuchi T. Koike H. Kumawat Y. Matsumoto K. Miwa M. Moritsu T. Nagae M. Naruki M. Niiyama Y. Nozawa R. Ota A. Sakaguchi H. Sako V. Samoilov S. Sato K. Shirotori H. Sugimura S. Suzuki T. Takahashi T. N. Takahashi H. Tamura T. Tanaka K. Tanida A. O. Tokiyasu Z. Tsamalaidze B. J. Roy M. Ukai T. O. Yamamoto S. B. Yang 《Few-Body Systems》2013,54(7-10):1191-1194
In the J-PARC E27 experiment, we search for a K ? pp bound state via the d(π +, K +) reaction at 1.7 GeV/c at the K1.8 beam line. The binding energy and decay width of the K ? pp bound state can be obtained in the missing mass measurement with a good energy resolution of 2 MeV/c 2. A range counter array (RCA) was constructed to detect the two high-momentum protons from the K ? pp decay and to reduce the background such as quasi-free hyperon production. Recently, we have carried out a pilot run in June, 2012. The d(π +, K +) missing-mass spectrum has been obtained for the first time. In this report, an overview of the E27 experiment and a preliminary result on this pilot run are presented. 相似文献