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141.
Kurmoo M Kumagai H Chapman KW Kepert CJ 《Chemical communications (Cambridge, England)》2005,(24):3012-3014
Reversible crystal-to-crystal transformation accompanied by change from ferromagnetic to antiferromagnetic ground states at 8 K upon dehydration-rehydration of the nanoporous coordination framework [CoII3(OH)2(C4O4)2].3H2O. 相似文献
142.
For integers a and b, 0 ? a ? a ? b, an [a, b]-graph G satisties a ? deg(x, G) ? b for every vertex x of G, and an [a, b]-factor is a spanning subgraph F such that a ? deg(x, F) ? b for every vertex x of F. An [a, b]-factor is almost-regular if b = a + 1. A graph is [a, b]-factorable if its edges can be decomposed into [a, b]-factors. When both K and t are positive integers and s is a nonnegative integer, we prove that every [(12K + 2)t + 2ks, (12k + 4)t + 2ks]-graph is [2k,2k + 1]-factorable. As its corollary, we prove that every [r.r + 1]-graph with r ? 12k2 + 2k is [2k + 1]-factorable, which is a partial extension of the two results, one by Thomassen and the other by Era. 相似文献
143.
144.
Mikio Hori Tadashi Kataoka Hiroshi Shimizu Sachio Ohno Kenichi Narita Hiroaki Takayanagi Haruo Ogura Yoichi Iitaka 《Tetrahedron letters》1979,20(44):4315-4318
The first success of an X-ray analysis of a thiabenzene derivative, 1-benzoyl-2-methyl-2-thianaphthalene is described. 相似文献
145.
Zheng-Yu Wang Mikio Konno Shozaburo Saito 《Journal of Polymer Science.Polymer Physics》1993,31(4):461-466
Suzuki's scaling theory for transient phenomena is applied to the calculation of the kinetics of phase separation in the early-to-intermediate stage based on a nonlinear theory proposed by Langer, Bar-on, and Miller (LBM). Calculated results are compared with experimental data on light scattering from a polymer blend system. Deviations from predictions of Cahn's linearized theory in the early time range of phase separation can be explained well by the proposed method of calculation. Nonlinear effects are found to play an essential role in characterizing the light scattering behavior of phase separation in the intermediate stage. Time evolutions of the single-point distribution function of composition are calculated, and the results are in good agreement with those reported in digital imaging analysis experiments and computer simulations of the time-dependent Ginzburg-Landau equation. The influence of asymmetry of free-energy on the single-point distribution function is also investigated in this study. © 1993 John Wiley & Sons, Inc. 相似文献
146.
147.
T. Tsuchiya F. Yamaguchi I. Morimoto T. Nakajima T. Kumagai 《Applied Physics A: Materials Science & Processing》2010,98(4):745-749
A tin-doped indium oxide (ITO) film on a SiO2 substrate was prepared by photo-irradiation of spin-coated nanoparticles using a Xe excimer lamp and a KrF excimer laser.
The effects of the excimer lamp and the excimer laser on the resistivity, mobility, and carrier concentration of the film
were investigated. To better understand how to control the microstructure of the film, we investigated the effect of thickness
on the resistivity of a film prepared by the two-step process, and found that the resistivity was higher in a thicker film.
Using two-step irradiation plus one-step KrF irradiation in N2 at room temperature, we produced an ITO film with lowest resistivity of any in this study. The electrical resistivity of
this film was 5.94×10−4 Ω cm. On the other hand, when using a simple thermal process, the resistivity of a film sintered at 500°C in N2 was 4.10×10−3 Ω cm. The differences in resistivity are discussed on the basis of the microstructure of the films using atomic force microscopy
and Hall measurements. 相似文献
148.
Tetsuo Tsuchiya Akio Watanabe Tomohiko Nakajima Toshiya Kumagai 《Applied Physics A: Materials Science & Processing》2010,101(4):681-684
Europium-doped yttrium oxide (Y2O3:Eu) thin films were successfully deposited on quartz and ITO/glass substrates by excimer-laser-assisted metal organic deposition
(ELAMOD) at low temperatures. The effects of laser wavelength and thermal temperature on the films’ crystallinity and photoluminescence
properties were investigated. Films irradiated by an ArF laser at 80 mJ/cm2 and 400–500°C were highly crystallized compared with those prepared by thermal MOD. In contrast, when the film was irradiated
by a KrF laser at 500°C, no crystalline Y2O3:Eu was formed. The Y2O3:Eu film irradiated by the ArF laser at 80 mJ/cm2 and 500°C showed typical PL spectra of Eu3+ ions with cubic symmetry and a 5D0→7F2 transition at ∼612 nm. The PL intensity at 612 nm was much higher for the film prepared with ELAMOD than for that prepared
by the thermal-assisted process, and the photoemission intensity of the film prepared with ELAMOD strongly depended on the
substrate material. 相似文献
149.
M. K. Kabir S. Kawata K. Adachi H. Tobita N. Miyazaki H. Kumagai 《Molecular Crystals and Liquid Crystals》2013,570(2):491-496
Abstract Hydrogen bond supported new iron-chloranilate assemblies, {(Hpy)[Fe(CA)2(H2O)2](H2O)}n (py = pyridine, H2CA = chloranilic acid, C6H2O4Cl2) (1), and [(phz)2[Fe(CA)2(H2O)2](H2O)2]n (phz = phenazine, C12H8N2) (2) have been synthesized and characterized. Compound 2 crystallizes in the monoclinic, space group C2/m (#12), with a= 29.135(6) Å, b= 16.886(6) Å, c = 15.017(5) Å, ß = 165.907(1)°, V= 1798(2) Å3, Z = 2. In both the compounds two chloranilate dianions and two water molecules are coordinated to the iron ion making anionic monomers [Fe(CA)2(H2O)2]?, which are the building blocks of the compounds. The coordination environment around the iron ion in the building block is a distorted octahedron, where two water molecules sit on the trans position to each other. [Fe(CA)2(H2O)2]? anions form common layer structures, supported by hydrogen bonds. Hpy+ are intercalated in between the layers of 1 by electrostatic and hydrogen bonding interactions and phz are intercalated in that of 2 by electrostatic interactions. DSC traces of 1 show anomaly at 174 K, indicating phase transition in the compound. 相似文献
150.
We consider a certain class of nonsymmetric Markov chains and obtain heat kernel bounds and parabolic Harnack inequalities. Using the heat kernel estimates, we establish a sufficient condition for the family of Markov chains to converge to nonsymmetric diffusions. As an application, we approximate nonsymmetric diffusions in divergence form with bounded coefficients by nonsymmetric Markov chains. This extends the results by Stroock and Zheng to the nonsymmetric divergence forms. © 2012 Wiley Periodicals, Inc. 相似文献