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111.
Gd(x)Y(1-x)Ca4O(BO3)3 (GdYCOB) is a promising nonlinear optical crystal that shows high effective nonlinearity d(eff), noncritical phase matching, and high chemical stability. We report on the fabrication and characteristics of a monolithic wavelength converter, which generates ultraviolet light by the incidence of a 1.064 microm near-infrared laser. The converter consists of GdYCOB for third-harmonic generation, KTiOPO4 (KTP) for second-harmonic generation, and a wave plate. GdYCOB has the advantage of an extremely wide angular acceptance bandwidth, whereas KTP exhibits a high effective nonlinear coefficient and a broad temperature bandwidth. Consequently the combination of these crystals results in highly efficient and stable ultraviolet conversion for constructing a compact and robust ultraviolet laser. 相似文献
112.
The sex pheromones of four Plusiinae species in the family Noctuidae, Ctenoplusia albostriata (CA), Macdunnoughia purissima (MP), Syngrapha ain (SA), and Diachrysia stenochrysis (DS) were identified by GC-EAD and GC-MS analyses. These were subsequently evaluated by a series of field trials in different ecological habitats. CA females produced (Z)-5-decenyl acetate (I), (Z)-7-dodecenyl acetate (II), and (Z)-7-dodecen-1-ol (III) in a ratio of 2:100:13. While the antennae of CA males responded to all three components, neither I nor III was essential to capture males. The MP females produced II, III, and (Z)-5-dodecenyl acetate (IV) in a ratio of 100:80:20, and this blend captured the most MP males. Compounds II and III were also identified from SA females, and mixtures ranging from 4:1 to 2:3 were equally attractive to males. DS females only produced one active compound, (Z)-7-decenyl acetate (V), and DS is the first Plusiinae species identified as using only the ω3-compound and none of ω5-compounds, such as II and III, which are common components of Plusiinae pheromones. Using previously published chemical and biosynthetic data, together with the finding from this study, we propose a classification of the Plusiinae sex pheromones. 相似文献
113.
Saburo Hosokawa Yukihiro Hayashi Seiichiro Imamura Kenji Wada Masashi Inoue 《Catalysis Letters》2009,129(3-4):394-399
Ceria colloidal particles with a mean crystallite size of 2 nm were synthesized by a solvothermal reaction. The Ru/CeO2 catalyst prepared from the CeO2 colloids exhibited higher activity than the catalyst prepared from Ce(NO3)3. Temperature-programmed reduction analysis indicated that the reduction of surface Ce4+ was accelerated by highly dispersed Ru species on the CeO2 particles and occurred at low temperatures. The single component CeO2 sample prepared by the coagulation of the CeO2 colloid was more easily reduced and re-oxidized than the CeO2 sample prepared by the precipitation method from Ce(NO3)3. The higher activity of Ru/CeO2 prepared from the CeO2 colloids came from the inherent nature of the CeO2 support itself. 相似文献
114.
Nobutaka Maeda Takaaki Matsushima Masashi Kotobuki Toshihiro Miyao Hiroyuki Uchida Hisao Yamashita Masahiro Watanabe 《Applied Catalysis A: General》2009,370(1-2):50-53
Pt–Fe/mordenite (4 wt% Pt–0.5 wt% Fe) powder catalysts were wash-coated onto ceramic straight-channel monoliths by using silica- and/or alumina-sol as a binder, and were evaluated for the preferential oxidation of carbon monoxide (PROX) in a hydrogen-rich gas. In a synthetic reformate gas (1% CO, 1% O2, 5% H2O, 20% CO2, and balance H2), the CO concentration was reduced to less than 20 ppm at temperatures ranging from 100 to 130 °C. After a certain period of the PROX reaction, condensation of H2O in the pores of the mordenite-support occurred over the monolithic catalyst, which was wash-coated with alumina-sol, in the lower temperature range (100–120 °C), resulting in a rapid increase in CO concentration. The monolithic catalyst wash-coated with silica-sol, however, showed an excellent tolerance against H2O condensation and offered a stable catalytic performance, maintaining a CO concentration of ca. 20 ppm for 200 h. The H2O-tolerant characteristic was attributed to the relatively small adsorption amount of H2O over the silica-modified monolithic catalyst. 相似文献
115.
Akira Kaieda Dr. Masashi Takahashi Hiromi Fukuda Dr. Rei Okamoto Dr. Shinji Morimoto Masayuki Gotoh Takahiro Miyazaki Yuri Hori Satoko Unno Dr. Tomohiro Kawamoto Dr. Toshimasa Tanaka Dr. Sachiko Itono Terufumi Takagi Dr. Hiroshi Sugimoto Dr. Kengo Okada Dr. Weston Lane Dr. Bi-Ching Sang Dr. Kumar Saikatendu Dr. Shinichiro Matsunaga Dr. Seiji Miwatashi 《ChemMedChem》2019,14(24):2093-2101
We identified novel potent inhibitors of p38 mitogen-activated protein (MAP) kinase using a structure-based design strategy, beginning with lead compound, 3-(butan-2-yl)-6-(2,4-difluoroanilino)-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one ( 1 ). To enhance the inhibitory activity of 1 against production of tumor necrosis factor-α (TNF-α) in human whole blood (hWB) cell assays, we designed and synthesized hybrid compounds in which the imidazo[4,5-b]pyridin-2-one core was successfully linked with the p-methylbenzamide fragment. Among the compounds evaluated, 3-(3-tert-butyl-2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-6-yl)-4-methyl-N-(1-methyl-1H-pyrazol-3-yl)benzamide ( 25 ) exhibited potent p38 inhibition, superior suppression of TNF-α production in hWB cells, and also significant in vivo efficacy in a rat model of collagen-induced arthritis (CIA). In this paper, we report the discovery of potent, selective, and orally bioavailable imidazo[4,5-b]pyridin-2-one-based p38 MAP kinase inhibitors. 相似文献
116.
Phytoextraction by a high-Cd-accumulating rice: reduction of Cd content of soybean seeds 总被引:1,自引:0,他引:1
Murakami M Ae N Ishikawa S Ibaraki T Ito M 《Environmental science & technology》2008,42(16):6167-6172
Soybeans (Glycine max (L) Merr.) are the major summer crop grown in Japanese upland fields (characterized by aerobic soil) that have been converted from paddies. To evaluate the effect of phytoextraction by rice on the seed cadmium (Cd) content of soybeans grown subsequently, we grew Milyang 23, a high-Cd-accumulating rice cultivar, and then grew soybeans in three paddy soils contaminated with moderate Cd concentrations (2.50-4.27 mg Cd kg(-1)). The rice accumulated 7-14% of the total soil Cd in its shoots. The soybean seed Cd contents were 24-46% less than those grown on control soils. Phytoextraction by Milyang 23 rice is thus a promising remediation method for reducing seed Cd contents of soybeans grown on paddy soils under aerobic soil conditions. 相似文献
117.
118.
Atsushi Tsujita Masashi Ohchi Takayuki Wakimoto 《Electrical Engineering in Japan》2019,208(1-2):17-26
We have been studying on estimating distribution of permittivity between measurement electrodes using capacitance and electric potential. Two arc electrodes were separated by long distance and there electrodes were surrounded by additional electrodes respectively. In past research work, we carried out numerical electric analysis for calculating the capacitance and electric potential using Finite Element Method (FEM) and compared with experimental and numerical results. The capacitance values were almost agreed with experimental and numerical results. However, the electric potential values were different between experimental and numerical results in conventional studies. In this paper, we proposed an equivalent circuit including the stray capacity and measurement method for capacitance, the electric potential in space between long distance electrodes was estimated. 相似文献
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