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1.
Toshihiko Hoshiro 《Journal d'Analyse Mathématique》2003,91(1):211-230
This article discusses some smoothing estimates of the initial value problem for dispersive equations with constant coefficients.
In particular, it is shown that a certain condition for the principal part of the symbol (see the assumption (1.3) below,
which is equivalent to the one “of principal type” in the paper by Ben-Artzi and Devinatz [2]) is necessary and sufficient
for the maximal smoothing in space-time.
Dedicated to Professor Norio Shimakura
The author was supported in part by Grant-in-Aid for Scientific Research, Ministry of Education, Culture, Sports, Science
and Technology, Japan (No. 13640187). 相似文献
2.
Edgar Heilbronner Rolf Gleiter Toshihiko Hoshi Armin de Meijere 《Helvetica chimica acta》1973,56(5):1594-1604
To obtain further information concerning the interaction between Walsh-orbitols of ‘conjugated’ cyclopropane rings, the photoelectron spectra of the following compounds have been recorded: bicyclo[4.1.0]heptane 1 , cis- and trans-tricyclo[5.1.03, 5]octane 2, 3 , diademane 4 , trans-pentacyclo[3.3.2.02, 9.04, 10, 06, 8]decan 5 and bicyclo[4.1.0]heptene-2 6 . The first bands in the PE.-spectra of these compounds have been assigned on the basis of a ZDO HMO-approximation. For 2 and 4 the value for resonance integral between linked 2p atomic orbitals of two adjacent eclipsed cyclopropane rings is found to be ?1.73 eV. 相似文献
3.
Hanai T 《Journal of chromatography. A》2004,1030(1-2):13-16
Retention mechanism on a graphitic carbon was analyzed by computational chemical calculation. The model graphitic carbon phase was a large polycyclic aromatic hydrocarbon (PAH) and analytes were carbohydrates and hydrocarbons separated by liquid and gas chromatography. Molecular mechanics calculation was fast and suggested their retention order and main retention force. Molecular orbital package calculation (MOPAC) demonstrated their complex form. 相似文献
4.
5.
Nakanishi I Miyazaki K Shimada T Iizuka Y Inami K Mochizuki M Urano S Okuda H Ozawa T Fukuzumi S Ikota N Fukuhara K 《Organic & biomolecular chemistry》2003,1(22):4085-4088
Electron-transfer reduction of molecular oxygen (O2) by the phenolate anion (1-) of a vitamin E model, 2,2,5,7,8-pentamethylchroman-6-ol (1H), occurred to produce superoxide anion, which could be directly detected by a low-temperature EPR measurement. The rate of electron transfer from 1- to O2 was relatively slow, since this process is energetically unfavourable. The one-electron oxidation potential of 1- determined by cyclic voltammetric measurements is sufficiently negative to reduce 2,2-bis(4-tert-octylphenyl)-1-picrylhydrazyl radical (DOPPH*) to the corresponding one-electron reduced anion, DOPPH-, suggesting that 1- can also act as an efficient radical scavenger. 相似文献
6.
Soh N Imato T Kawamura K Maeda M Katayama Y 《Chemical communications (Cambridge, England)》2002,(22):2650-2651
A novel fluorescent probe, which could be the first example of a ratiometric molecular probe for direct monitoring of NO production, has been developed using a 'spin-exchange' mechanism. 相似文献
7.
The total synthesis and an unambiguous structure confirmation of stevastelin B 1, a novel 15-membered cyclic depsipeptide, are described; the fatty acid moiety in 1, prepared stereoselectively from L-quebrachitol was converted into the amino carboxylic acid, whose macrolactamization by Shioiri's procedure effectively constructed the cyclic structure of 1. 相似文献
8.
Michiya Itoh Kenji Murata Kunihiro Tokumura Koichi Shudo Naoki Miyata Toshihiko Okamoto 《Tetrahedron》1979,35(9):1059-1063
Photorearrangement reactions of K-region arene oxides, 9,10-epoxy-9,10-dihydrophenanthrene (1a), 3-acetyl-9,10-epoxy-9,10-dihydrophenanthrene (1b), and 3,4-epoxy-3,4-dihydropyrene (1c) in dichloroethane (DCE) solution were investigated by steady irradiation and nanosecond transient spectroscopy. Photorearrangements producing substituted oxepins, 2 occur via the singlet excited state of these compounds, while the phenolic products, 9-hydroxyphenanthrene (3a), 3-acetyl-9-hydroxyphenanthrene (3b), and 4-hydroxypyrene (3c) are formed via the triplet state. Phenol 3 formation from the triplet 1 sensitized by the triplet 3 (i.e. product sensitization) is proposed for the photorearrangement reactions of 1a and 1c, and this process is the only way phenol (3a) is formed because of the negligible intersystem crossing probability of 1a. No product sensitization occurs in the photorearrangement reaction of 1b. 相似文献
9.
When a mixed solution of 0.72 M potassium and sodium chloride was eluted from a Sephadex G-15 column with 0.025 M sodium phosphate buffer (pH 7.0), the elution profiles of ions showed that the potassium and chloride ion pair from the sample and the sodium and chloride ion pair produced by ion-exchange reaction, were eluted in the same fractions as if they constituted a complex. When a mixed solution of different concentrations of potassium and sodium chloride was eluted with the same buffer, the excess amount of one ion pair over the other was eluted freely from the presumed complex. 相似文献
10.
Takuo Kosuge Kuniro Tsuji Koichi Hirai Kentaro Yamaguchi Toshihiko Okamoto Yoichi Iitaka 《Tetrahedron letters》1981,22(35):3417-3420
A new toxin, named neosurugatoxin, was isolated from the toxic Japanese Ivory Shell and its structure was determined by X-ray crystallographic analysis. 相似文献