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11.
K Kawakami R Amakawa S Miyanishi A Okumura T Hayashi M Kurata H Ohno Y Ohno S Fukuhara 《Canadian Metallurgical Quarterly》1998,67(2):191-198
Appropriately substituted 2,3-dihydro-7H-thiazolo[3,2-a]pyrimidin-7-ones 9-12 and 18 were considered as annulated analogues of HEPT (1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)-thymine), and some of these compounds were also found active against HIV-1, the most active one being 2,3-dihydro-5-[(3,5-dimethylphenyl)methyl]-3-ethoxy-6-ethyl-7H- thiazolo[3,2-a]pyrimidin-7-one (10b). S-Alkylation of 5-alkyl-6-(arylmethyl)-2-thiouracils 1-4 was performed with 2-bromoacetaldehyde acetals to furnish the S-[bis(alkoxy)ethyl] derivatives 5-8 and with allyl bromide to furnish S-allyl derivatives 17. The target compounds 9-12 were obtained by an N1 regioselective intramolecular cyclization reaction of silylated 5-8 using trimethylsilyl trifluoromethanesulfonate (TMS triflate) as the catalyst. Treatment of the S-allyl derivatives 17 with bromine in dry methylene chloride afforded the 3-(bromomethyl) derivatives 18. 相似文献
12.
Takuya Uehara Hiroshi Kitahara Hideshi Naka Shigeru Matsuyama Tetsu Ando Hiroshi Honda 《Journal of chemical ecology》2016,42(6):517-522
Recent work has suggested that hawk moths share pheromone components but are sexually separated by qualitative and quantitative differences in their pheromone blends. During field assays on the sex pheromones of other species, a diurnal hawk moth, Neogurelca himachala sangaica (Lepidoptera: Sphingidae), was frequently captured, but the composition of the sex pheromone of this species was not known. Analysis of hexane extracts of the pheromone glands of calling female by gas chromatography (GC) using an electroantennographic detector (EAD) revealed two components that elicited EAD responses from male moth antennae. These components were identified by their mass spectra and retention indices on two GC columns as (10E,12Z)-10,12-hexadecadienal (E10,Z12–16:Ald) and a trace of its (10E,12E)-isomer (E10,E12–16:Ald) in 98:2 ratio. In field experiments, E10,Z12–16:Ald alone attracted male moths, and addition of E10,E12–16:Ald significantly reduced the attractiveness, even at the naturally-occurring ratio. Analysis of the data using a generalized linear mixed model showed that E10,Z12–16:Ald positively contributed to attractiveness, whereas E10,E12–16:Ald did so negatively, and it was concluded that the sex pheromone of N. himachala sangaica consists solely of E10,Z12–16:Ald, bombykal. The negative effect of E10,E12–16:Ald on attractiveness could promote the species-specificity of this single-component pheromone system. 相似文献
13.
Hideshi Suzuki Masahiro Ogawa Kenji Hironaka Kunio Ito Hisakazu Sunada 《Drug development and industrial pharmacy》2001,27(9):951-958
Nifedipine is a poorly water soluble drug that demonstrates low bioavailability. In a previous study, a coground mixture of nifedipine with sodium deoxycholate (DCNa), a bile salt, immediately produced colloidal particles when dispersed in water. In this study, the effect of the weight fraction of DCNa, grinding time, dissolution media, and storage conditions on colloidal particle formation in solution was investigated. The coground mixture was prepared with a vibration rod mill, and its solid state was characterized using powder X-ray diffraction. A laser diffraction particle size analyzer was used to determine the particle size distribution curve in water. The size of particles formed in solution decreased with an increase in the weight fraction of DCNa and grinding time. A nifedipine-DCNa (1 : 2 w/w) mixture coground for 30 min was used in the experiments. Colloidal particle formation from the coground mixture was also observed in dissolution media of water and a pH 6.8 buffer solution at 37°C. Most precipitates passed through a filter with a pore size of 0.8 μm, but the particle size distribution in water was different from that in the pH 6.8 buffer solution. DCNa exhibited not only micellar solubilization for drug crystals, but also a retarding effect on drug crystal growth in a supersaturated solution. The latter effect could serve to form colloidal particles in solution. When stored under 75% relative humidity at 40°C for 1 month, the amorphous coground mixture crystallized, and the particle size in water markedly increased. Therefore, the weight fraction of DCNa, grinding time, dissolution media, and humidity during storage influence the dissolution characteristics of nifedipine from a coground mixture. 相似文献
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Hideshi Ishida Takayuki YamashitaHideo Kimoto 《International Journal of Heat and Mass Transfer》2002,45(16):3471-3476
In this study artificial disturbances were introduced into a wall plume adjacent to a vertical side wall, and its stability and chaotic characteristics were experimentally examined. The main results are: (1) for high and low frequency disturbances the neutral region (a region between stability and instability) is lower and higher values of the modified Grashof number than an analytical neutral curve, respectively. (2) As the Grashof number increases, a chaotic fluctuation of temperature is observed above a critical value. This chaotic region is completely included in the region where the wall plume is unstable. (3) The flow can be classified into four regions based on patterns, a stable region, disturbance-amplification region, chaotic region and non-chaotic region. 相似文献
18.
Michael Zeutzius Toshiaki Setoguchi Toshihiro Nakano Hideo Miyanishi Kunio Terao Saga University Honjo Saga - Japan 《热科学学报(英文版)》2000,(2)
~nonEmphasising time characterishcs and contIDI, onlyfew workll'v is av'ailable among the numerous reports onPulse combustors. Rare work deals with tWin Pulsecombustorsls] or combined pulse combustor-"dinesystemsl']. Kenffield15] obtained with a combinedconvenhonal Pulse combustor-tulbine system acombushon Pressals gain of 3-7% and a totalPerformance Of the combustor-"dine system for Pulsecombushon 40% higher than that of steady'combushonwhat aught also be due tO the brine characteristics.… 相似文献
19.
Okamoto K Narayama S Katsuo A Shigematsu I Yanase H 《Journal of Bioscience and Bioengineering》2002,93(2):207-210
The white-rot basidiomycete Pleurotus ostreatus produced sweet flavor compounds on a liquid medium. The major and minor compounds identified by GC-MS analysis were p-anisaldehyde (4-methoxybenzaldehyde) and 3-chloro-p-anisaldehyde (3-chloro-4-methoxybenzaldehyde), respectively. p-Anisaldehyde was only produced under static culture conditions. Differences in the type and quantity of flavor compounds produced among wild strains of P. ostreatus were observed. Aryl alcohol oxidase and manganese peroxidase activities increased parallel to the production of p-anisaldehyde. These results indicated that the biosynthesis of p-anisaldehyde is concerned in generating H2O2-activated peroxidase in the lignin-degradation system. Addition of L-tyrosine to the culture led to higher production of p-anisaldehyde. The flavor extract, which contains p-anisaldehyde, exhibited antimicrobial activity against Bacillus subtilis, Pseudomonas aeruginosa, Aspergillus niger and Fusarium oxysporum. 相似文献
20.
Hideshi Ishida Shiho Ihara Chiharu Okema Shohei Yamada Genta Kawahara 《Numerical Heat Transfer, Part B: Fundamentals》2013,63(4):185-202
AbstractThis study demonstrates a global, nonparametric, noniterative optimization of time-mean value of a kind of index vibrated by time-varying forcing. It is based on the fact that the (steady) forced vibration of nonautonomous ordinary differential equation systems is well approximated by an analytical solution when the amplitude of forcing is sufficiently small and its base state without forcing is linearly stable and steady. It is applied to optimize a time-averaged heat-transfer rate on a two-dimensional thermal convection field in a square cavity with horizontal temperature difference, and the globally optimal way of vibrational forcing, i.e. the globally optimal, spatial distribution of vibrational heat and vorticity sources, is first obtained. The maximized vibrational thermal convection corresponds well to the state of internal gravity wave resonance. In contrast, the minimized thermal convection is weak, keeping the boundary layers on both sidewalls thick. 相似文献