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21.
Tetsu Ando Hirokazu Ohsawa Tadahiro Ueno Hideki Kishi Yutaka Okamura Satoshi Hashimoto 《Journal of chemical ecology》1993,19(4):787-798
Although several sex pheromones of the family Geometridae have been characterized, investigations on Japanese species are limited. In order to obtain more information, screening using known sex pheromones and their analogs was carried out. The (Z,Z,Z)-3,6,9-triunsaturated and (Z,Z)-6,9-diunsaturated hydrocarbons with straight C19-C21 chains were synthesized by the Grignard coupling reaction as a key step starting from linolenic and linoleic acids, respectively. Oxidation of the homoconjugated trienes withm-chloroperoxybenzoic acid yielded a 111 mixture of three monoepoxy derivatives that could be separated by silica gel chromatography. The chemical structure of each positional isomer was confirmed using two-dimensional NMR techniques and MS measurements, which enabled characteristic fragment ions from the isomers to be identified. Field tests using lures incorporating only one of the above six hydrocarbons or nine epoxides were carried out in a forest in Tokyo. Consequently, attraction of male moths of 14 geometrid species in addition to four species in another family, the Noctuidae, was observed. It was concluded that hydrocarbons with a homoconjugated polyene system and the monoepoxy derivatives are important components of sex pheromones produced by Japanese lepidopterous insects, particularly the geometrid moths. 相似文献
22.
This paper reports the fabrication process of β-FeSi2 droplets on silicon substrates at room temperature by ArF excimer pulsed laser deposition (PLD). The chemical treatment of substrate could compensate the thermal treatment of the deposited droplets. Observations with the transmission electron microscopy revealed that the crystallization of droplet began from the surface of droplet rather than from the interface between the melt and the substrate. 相似文献
23.
T Ashikaga M Nishizaki M Arita N Yamawake Y Kishi F Numano M Hiraoka 《Canadian Metallurgical Quarterly》1998,82(6):814-6, A10
This study found that increased QT dispersion just before angioplasty is an useful marker to predict the risk for lethal ventricular arrhythmias during angioplasty. The fact that successful coronary revascularization decreased QT dispersion suggested that a part of increased QT dispersion is related to myocardial ischemia. 相似文献
24.
Kishi N. Sano T. Yamashita E. 《IEEE journal of selected topics in quantum electronics》1997,3(4):1045-1048
The paper describes the characterization of an improved fiber-optic transceiver for optical time-domain reflectometers (OTDR). The transceiver employs an active fiber ring which has both transmitter and receiver functions of OTDR. An optical circulator takes the place of the combination of a 3-dB coupler and an optical isolator in the previously reported system. Reflections from several lengths of cascaded fibers are measured to characterize the transceiver. Compared with the previous system, performance improvement of the transceiver with the optical circulator is achieved 相似文献
25.
M. Aoyama J. Temuujin M. Senna T. Masuko C. Ando H. Kishi 《Journal of Electroceramics》2006,17(1):61-64
Z-type hexaferrites (Ba3(1 − x)Sr3x
Co2Fe24O41with x = 0–0.5, Z-hex) were prepared in a nearly phase pure state by a two-step calcination with an intermediate wet milling. The
first calcination of the starting mixture comprising oxides or hydroxides at temperatures below 1100∘C brought about a mixture of layer-structured M and Y-type hexaferrite phases, together with a spinel phase of Co ferrite.
Z-hex was fully crystallized after the second calcination up to 1230∘C. Wet milling between the two calcination steps was decisive for the phase purity. Emphasis was laid on the quantitative
analyses of Z-hex, together with the evaluation of anisotropic growth of the crystallites. Sr addition stabilizes Z-hex, while
decreases degree of anisotropy simultaneously. 相似文献
26.
Hiroshi Kishi Youichi Mizuno Tomoya Hagiwara Hirokazu Orimo Hitoshi Ohsato 《Journal of Electroceramics》2008,21(1-4):22-28
The effect of re-oxidation treatment on the solubility of dopants and the dielectric properties of rare-earths (La, Ho) and V-substituted BaTiO3 solid solutions, assuming the shell phase of X7R dielectrics, was investigated. Ho-V-substituted samples showed larger increase of the lattice parameter and T c by re-oxidation treatment compared with La-V-substituted samples. Electron spin resonance measurements revealed that the oxidation of V3+ to V4+ or V5+ appeared in the range in which the increase of lattice parameter by re-oxidation treatment was observed. This suggests that the increase of T c is due to the change of preferential occupational site of Ho ion from A-site to B-site, being accompanied with the oxidation of V3+. We also investigated the effect of re-oxidation treatment on the electrical properties and microstructure in Ni-MLCC samples, using rare-earths (La, Ho, Yb) and acceptors (Mn, V) doped BaTiO3 based X7R dielectrics. The change in temperature characteristic of the dielectric constant by re-oxidation treatment was observed for the MLCC samples containing V with smaller content. In the case of Ho-V- and Yb-V-doped samples showed larger increase of the dielectric constant at around 120 °C compared with La-V-doped samples. The relationship between the microstructure and electrical properties of the MLCC sample was investigated by impedance measurement at elevated temperature. 相似文献
27.
The point-matching technique on boundary conditions is applied to the modal analysis by extending the method in a previous paper by the authors (ibid., vol.LT-4, p.991-6, 1986). The coupling-field characteristics of the optical fibers are then analyzed on the basis of the superposition of eigenmode fields thus obtained. Numerical results in the case of four, five, and six cores indicate that coupling strength is not always a periodic function of propagation length unlike the case of dual-core structures 相似文献
28.
We have developed a novel electrolytic system for anodic acyloxylation based on the acid–base reactions between acetic acid or trifluoroacetic acid and solid-supported bases. On the basis of the electrolytic system, anodic acyloxylation of organic compounds, which even have considerably high oxidation potentials, was successfully carried out to provide the corresponding acyloxylated products in moderate to excellent yields. Furthermore, it was found that silica gel supported bases are not only chemically stable under acidic conditions but also electrochemically stable and thus reusable for many times. 相似文献
29.
Vectorial wave analyses of uniform-core optical fibers using a boundary integral method that does not use Green's function are presented. The expansion of the electromagnetic field on the boundary, the selection of the weight function, and the method for giving boundary conditions are discussed. By using the formulation obtained, the propagation characteristics of elliptical-core optical fibers are analyzed. The effect of the boundary shape on the numerical results is also investigated through analyses of rectangular-core fibers. It is found that the boundary integral method can easily be applied to solve vectorial wave boundary value problems 相似文献
30.
Wakasugi K. Naru-Fumi Kishi Matsuo M. 《Geoscience and Remote Sensing, IEEE Transactions on》1986,(5):732-737
An analytic model of the ocean surface SAR images with a three-dimensional framework is developed following the formalism presented by Swift and Wilson (1979); a trochoidal swell propagates through a uniform field of Bragg-type distributed scatterers. Two- dimensional SAR images are calculated for the interpretation and prediction of actual SAR images of the ocean surface as a function of ocean wave amplitude, wave frequency, propagation direction, and radar frequency, off-nadir angle of the antenna, and spatial resolutions. 相似文献