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41.
42.
We consider a generalization of the Stokes resolvent equation, where the constant viscosity is replaced by a general given
positive function. Such a system arises in many situations as linearized system, when the viscosity of an incompressible,
viscous fluid depends on some other quantities. We prove that an associated Stokes-like operator generates an analytic semi-group
and admits a bounded H
∞
-calculus, which implies the maximal L
q
-regularity of the corresponding parabolic evolution equation. The analysis is done for a large class of unbounded domains
with -boundary for some r > d with r ≥ q, q′. In particular, the existence of an L
q
-Helmholtz projection is assumed. 相似文献
43.
44.
Following the characterization of myrciacitrins I and II and myrciaphenones A and B, three new flavanone glucosides, myrciacitrins III, IV, and V, were isolated from the leaves of Brazilian Myrcia multiflora. The structures of new myrciacitrins were elucidated on the basis of physicochemical and chemical evidence. Myrciacitrins were found to show potent inhibitory activity on aldose reductase. 相似文献
45.
Kiyohara K Asaka K Monobe H Terasawa N Shimizu Y 《The Journal of chemical physics》2006,124(3):034704
We studied the mechanism of surface anchoring of rodlike molecules on substrates with the surfaces corrugated at molecular scale by molecular-dynamics simulation. We constructed a model for substrates that can have anisotoropic topographical patterns such as corrugation. The structural and thermodynamic properties of rodlike molecules on the corrugated surfaces, including the elastic and anchoring properties, were calculated and the influence of the surface structure on the anchoring was discussed. We found that the rodlike molecules are aligned along the grooves of the corrugated surfaces guided by the anisotropic molecular interaction between the molecules and the corrugated surface. The strength of anchoring was found to be increased when the period of corrugation is decreased at molecular level. 相似文献
46.
Mikitoshi Nakada Norihisa Kobayashi Hiroyuki Ohno Eishun Tsuchida Hiro Matsuda Hachiro Nakanishi Masao Kato 《Journal of polymer science. Part A, Polymer chemistry》1987,25(12):3429-3435
1,3-Butadiyne was epitaxially polymerized on the graphite basal plane by chemical vapor deposition to form a homogeneous thin film. The film thickness varied from 100 to 3000 Å depending on the polymerization condition. The films on the graphite showed a variety of interference colors such as blue, purple, or gold depending on the film thickness. Raman spectra revealed that the polymerized film was mainly composed of ? C?C? bonds. Electron diffraction pattern and the ESCA spectrum of the film were quite similar to those of graphite, suggesting that butadiyne was polymerized in an epitaxial manner. 相似文献
47.
This report discusses the effect of fluoroalkyl chain on the mesomorphism. Several homologues of novel triphenylene compounds possessing fluoroalkylated side chains were synthesized. Studies of X-ray diffraction, DSC and texture observations by polarized microscope revealed that these homologues show hexagonal columnar (Colh) mesophase. These homologues made columnar mesophase stabilize and the melting point increase, as compared with corresponding alkyloxytriphenylenes. In the case of fluoroalkyloxytriphenylenes possessing fluoromethylene side chains, the increase of the fluoromethylene chain length stabilized columnar mesophase, made the phase transition enthalpy (Colh-Iso) and entropy (Colh-Iso) increase. It is considered that these results are due to the fluorophilic interaction, and that the fluorophilic interaction is important for stabilizing columnar mesophase. 相似文献
48.
Ken'ichi Hanaoka Toshikazu Kaise Norihisa Kai Yasuhiro Kawasaki Hideaki Miyasita Kenji Kakimoto Shoji Tagawa 《应用有机金属化学》1997,11(4):265-271
The arsenobetaine-decomposing ability of microorganisms occurring in sinking particles, which play a main role in the vertical transport of organic substances produced in the photic zone, was investigated. The microorganisms in particles collected in the deep sea, 1100 and 3500 m in depth, clearly showed decomposing ability. With the particles from 1100 m, the degradation products were the same as those produced by microorganisms occurring in sources in the photic zone, i.e. trimethylarsine oxide (TMAO), dimethylarsinic acid (DMA) and inorganic arsenic(V). At 3500 m, the degradation activity was diminished, smalls amount of DMA and TMAO being produced. These results suggest that arsenobetaine contained in the animals starts to degrade immediately after the death of the animals and their transformation to particles. The degradation of arsenobetaine to inorganic arsenic in our tentative arsenic cycle in marine ecosystems (inorganic arsenic to inorganic arsenic via the biosynthesis of arsenobetaine) may apply to the deep sea as well as to the photic zone. © 1997 by John Wiley & Sons, Ltd. 相似文献
49.
50.
Chiaki Hirose Nobuyuki Watanabe Hiroyoshi Yamamoto Akihide Wada Kazunari Domen T. Ohtake Norihisa Mino 《中国化学会会志》1994,41(3):275-278
The vibrational spectroscopy by way of vibrational sum-frequency generation (VSFG) has been made of formic acid adsorbed on MgO(001) surface and of n-alkyltrichlorosilanes chemisorbed on quartz plates. It was revealed that the species on the MgO surface was formate ion (HCOO+) with CH bonds standing vertical to the surface and that the different adsorption sites showed up on repeated cycles of adsorption-desorption processes. The results of chemisorbed films indicated that the g-t and/or g-t-g′ conformational scquences of n-alkyl chains occurred more frequently by the length of alkyl chain and that the surface hydroxyls, which are the sites of chemisorption, are ripped off by pre-exposure of substrate to oxygen plasma. 相似文献