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901.
In this paper we present a unified simple approach to anisotropic Hardy inequalities in various settings. We consider Hardy inequalities which involve a Finsler distance from a point or from the boundary of a domain. The sharpness and the non-attainability of the constants in the inequalities are also proved. 相似文献
902.
In this paper, we introduce an iterative scheme for finding a common fixed point of infinite nonexpansive mappings in a Hilbert space by using the hybrid method. Then, we prove a strong convergence theorem which is connected with the problem of image recovery. Further, using this result, we consider the generalized problem of image recovery and the problem of finding a common fixed point of a family of nonexpansive mappings. 相似文献
903.
Takayuki DoiNobuaki Fujimoto Jun WatanabeTakashi Takahashi 《Tetrahedron letters》2003,44(10):2161-2165
We have developed a practical route for the synthesis of peptides containing unnatural amino acids. Mizoroki-Heck reaction of polymer-supported dehydroalanine, followed by asymmetric hydrogenation was accomplished using Pd(0) and Rh(I)-DuPHOS catalysts, respectively, leading to 36 dipeptides containing phenylalanine derivatives with high stereocontrol. 相似文献
904.
Shuntaro Mataka Kazufumi Takahashi Masashi Tashiro Wei-Hua Lin Shin-Ichi Iwasaki Tetsuo Tsutsui Shogo Saito Shinji Akiyama Tadashi Yonemitsu 《Journal of heterocyclic chemistry》1989,26(1):215-219
Reversible color change of 4,6,7-tri(alkoxy-substituted phenyl)-1,2,5-thiadiazolo[3,4-c]pyridines 5 in the solid state was observed: on grinding, yellow crystals of 5 became an orange amorphous solid which, on heating or washing with an appropriate solvent, gave the original yellow crystals. 相似文献
905.
906.
907.
Terphenyl compounds, tentatively named Bl-I (1), Bl-II (2), Bl-III (3), Bl-IV (4) and Bl-V (5), showing 5-lipoxygenase inhibitory activity have been isolated from the mushroom Boletopsis leucomelas (Pers.) Fayod. On the basis of physico-chemical and spectral evidence, they were concluded to be a series of cycloleucomelone-leucoacetates. 相似文献
908.
Ichiro Ohba 《Foundations of Physics》1997,27(12):1725-1738
A novel method to quantize systems of damped motion is proposed in the frameworks of canonical quantization and path integral
quantization. It can be afforded by considering a Lagrangian multiplied by a time-dependent function, which may represent
an effective interaction with “environment.” 相似文献
909.
T. Ohsaka Y. Shibata K. Ishi S. Takahashi M. Ishii Y. Fujiki 《Solid State Communications》1985,55(12):1119-1121
The reflection spectra of the one-dimensional ionic conductors K1.6Al1.6Ti6.4O16 and Rb1.49Al1.65Ti6.35O15.92 have been measured for the polarizations E ∥ c (channel direction) and E 6 c in the frequency region 60–2000 cm-1. The spectra of these two compounds are very similar with their features and have the same number of bands. The vibrational mode frequencies are obtained from a Kramers-Kronig analysis for each polarized reflectivity spectrum. A comparison of the corresponding mode frequencies for both priderites shows that only the lowest frequency mode observed in the E 6 c spectra is strongly associated with the alkali ion, while the others are not. The effect due to the non-stoichiometry is not found in the infrared reflection spectra. 相似文献
910.
T Niwa W Maruyama D Nakahara N Takeda H Yoshizumi A Tatematsu A Takahashi P Dostert M Naoi T Nagatsu 《Journal of chromatography. A》1992,578(1):109-115
N-Methylsalsolinol, an analogue of 1,2,3,6-tetrahydropyridine, is present in the brains of patients with Parkinson's disease. To determine the metabolic pathway for the synthesis of N-Methylsalsolinol in the brain, salsolinol was perfused through the striatum or the substantia nigra of the rat brain by in vivo microdialysis. N-Methylsalsolinol was detected in the brain dialysate samples during microdialysis with salsolinol using gas chromatography-mass spectrometry with selected-ion monitoring. These results demonstrate that endogenous N-methylation of salsolinol into N-methylsalsolinol occurs in the brain in vivo. 相似文献