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131.
132.
1-Hydroxypiperazine dihydrochloride 7 was prepared and it was applied to the syntheses of new pyridone carboxylic acid antibacterial agents (PCA-antibacterial agents). 1-Cyclopropyl-6,8-difluoro-1,4-dihydro-7-(4-hydroxypiperazin-1-yl)-4-oxoquinoline-3-carboxylic acid 13 showed the most potent antibacterial activity.  相似文献   
133.
134.
A few existence theorems are proved for the models of an abelian variety of CM-type with a given zeta function over a field which does not necessarily contain the reflex field.  相似文献   
135.
Free electron laser (FEL) and self-amplified spontaneous emission (SASE) are being developed in the far-infrared region using the L-band electron linac at the Institute of Scientific and Industrial Research (ISIR), Osaka University. The L-band linac was recently remodeled extensively not only for higher operational stability and reproducibility but also for high power operation of FEL. After commissioning of the linac, we first began SASE experiment with a newly-developed strong-focusing wiggler. Recently we began FEL experiment and obtained lasing with the high peak power at 70 μm again after a long break.  相似文献   
136.
New techniques to determined the localized-state density in chemically vapour deposited amorphous silicon over a wide energy range by the field-effect method are presented. The density is measured for the first time as 1018 ~ 1020 cm?3 eV?1 in the range ±0.4~±0.5 eV around the Fermi level. From the results it is suggested that the silicon atom network of CVD a-Si has a similar randomness to that of glow discharge a-Si, providing a density of tail states of about 1019 ~ 1020 cm?3 eV?1 and native defect states of about 1018 cm?3 eV?1.  相似文献   
137.
Serial transmission electron microscopy of human megakaryocytes (MKs) revealed their polyploidization and gradual maturation through consecutive transition in characteristics of various organelles and others. At the beginning of differentiation, MK with ploidy 32N, e.g., has 16 centrosomes in the cell center surrounded by 32N nucleus. Each bundle of microtubules (MTs) emanated from the respective centrosome supports and organizes 16 equally volumed cytoplasmic compartments which together compose one single 32N MK. During the differentiation, single centriole separated from the centriole pair, i.e., centrosome, migrates to the most periphery of the cell through MT bundle, corresponding to a half of the interphase array originated from one centrosome, supporting one "putative cytoplasmic compartment" (PCC). Platelet demarcation membrane (DM) is constructed on the boundary surface between neighbouring PCCs. Matured PCC, composing of a tandem array of platelet territories covered by a sheet of DM is designated as protoplatelet. Eventually, the rupture of MK results in release of platelets from protoplatelets. (Communicated by Tadamitsu Kishimoto, M.J.A.).  相似文献   
138.
This paper addresses the analysis of dynamical systems generated by doubly nonlinear evolution equations governed by subdifferential operators with non-monotone perturbations in a reflexive Banach space setting. In order to construct global attractors, an approach based on the notion of generalized semiflow is employed instead of the usual semigroup approach, since solutions of the Cauchy problem for the equation might not be unique. Moreover, the preceding abstract theory is applied to a generalized Allen-Cahn equation as well as a semilinear parabolic equation with a nonlinear term involving gradients.  相似文献   
139.
This paper is concerned with the Weighted Energy-Dissipation (WED) functional approach to doubly nonlinear evolutionary problems. This approach consists in minimizing (WED) functionals defined over entire trajectories. We present the features of the WED variational formalism and analyze the related Euler-Lagrange problems. Moreover, we check that minimizers of the WED functionals converge to the corresponding limiting doubly nonlinear evolution. Finally, we present a discussion on the functional convergence of sequences of WED functionals and present some application of the abstract theory to nonlinear PDEs.  相似文献   
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