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61.
Kazuyuki Maeshima Nanao Hayashi Tadayuki Murakami Fumiki Takahashi Hisashi Komae 《Journal of chemical ecology》1985,11(1):1-9
Chemical components stimulating oviposition bySitophilus zeamais in rice grain were isolated from rice bran and were found to be a mixture of ferulates, diglycerides, and free sterols. Oviposition preference of the species can be induced by synergistic action of these compounds. 相似文献
62.
Chemical and Chromatic Bases for Preferential Visiting By the Cabbage Butterfly, Pieris rapae, to Rape Flowers 总被引:1,自引:2,他引:1
Scent and coloration of corolla were examined as floral attributes responsible for preferential visiting by the cabbage butterfly, Pieris rapae, to rape flower, Brassica rapa. Floral volatile components that release the flower-visiting behavior of the butterfly were identified by chemical analyses, electroantennography (EAG), and two behavioral bioassays: proboscis extension reflex (PER) in response to odor and attraction to artificial flowers. GC and GC-MS analyses of the headspace volatiles from the flowers revealed the presence of six aromatic compounds, benzaldehyde, phenylacetaldehyde, benzyl alcohol, 2-phenylethanol, phenylacetonitrile, and indole in decreasing order of quantity. Of these, phenylacetaldehyde elicited the highest response in the PER assay. While benzyl alcohol, 2-phenylethanol, benzaldehyde, and phenylacetonitrile evoked moderate responses, the PER-eliciting activity of indole was very weak. In two-choice behavioral bioassays, artificial flowers scented with any one of these PER-active compounds attracted significantly more butterflies than control (unscented) flowers, whereas those treated with indole were almost inactive. The EAG activities of the six chemicals were not high and were about the same at a low dose (1 g), but phenylacetaldehyde elicited a much stronger response from both sexes at higher doses (10 and 100 g). An overall profile of EAG responses at a dose of 100 g was analogous to that of PER performance, suggesting that floral volatiles may be involved in close-range location or recognition of flowers rather than long-range attraction. By spectroscopic and UV-photographic examinations of rape flower, the central part of the corolla was found to absorb UV rays in marked contrast to the other parts, which reflected near-UV rays (max = 350 nm). This indicates that the flower is endowed with a conspicuous nectar guide that is probably an important visual stimulus for attracting foraging adults of P. rapae. Consequently, the present findings strongly suggest that this elaborate pollination strategy of rape flower, characterized by its good combination of olfactory and visual attractiveness, accounts for preferential visiting by the cabbage butterfly to the flower. 相似文献
63.
The size distribution of gold nanoparticles was estimated based on the scattering intensity data obtained from small angle X-ray scattering (SAXS) and compared with the result of micrographs by transmission electron microscopy. The slope of the Guinier plot was used to estimate the mean size assuming a narrow particle size distribution. When the size distribution is narrow, the mean size can be easily obtained from slope of a Guinier plot of scattering data within 10% error. Additionally, assuming a lognormal size distribution, the size distribution and the mean size can be calculated using the experimental SAXS data in the fitting analysis. The histogram method, which utilizes the coefficient matrix of scattering intensity, was also applied to the estimation of the size distribution, and this method could be useful for a rough estimate of the size distribution. 相似文献
64.
Weidong Ding Ryota Hayashi Kohei Ochi Junya Suehiro Kiminobu Imasaka Masanori Hara Noriaki Sano Eiichi Nagao Tadao Minagawa 《Dielectrics and Electrical Insulation, IEEE Transactions on》2006,13(6):1200-1207
Chemical byproducts analysis has been recognized as a powerful diagnosis method for SF6 gas-insulated switchgear (GIS). The authors have previously demonstrated that a carbon nanotube (CNT) gas sensor could detect partial discharge (PD) generated in SF6 gas. However, PD-generated decomposition gas species, which were responsible for the CNT gas sensor response, have not been identified yet. In this paper, two kinds of experiments were conducted in order to identify the responsible decomposition gas species. At first, the decomposition gas molecules adsorbed on CNTs were analyzed by Fourier transformation infrared (FTIR) spectroscopy. FTIR absorbance was observed around 735 cm-1 after CNTs were exposed to PD generated in SF6. In the second experiment, the CNT gas sensor responses to typical SF6 decomposition products (HF and SF4) were examined. The CNT gas sensor responded to these gases in the same way as to PD generated in SF6. SF4 response was larger than HF response. Based on these results, SF 4 and SOF2 emerged as candidates for the responsible decomposition gases. Electrochemical interactions between adsorbed gas molecules and CNT were discussed based on theoretical predictions of molecular orbital calculations. The calculation results suggested that both of SOF2 and SF4 could increase the CNT gas sensor conductance 相似文献
65.
Nobuhiko Hayashi Yusuke Kato Manfred Sigrist 《Journal of Low Temperature Physics》2005,139(1-2):79-96
The low-temperature shrinking of the vortex core (Kramer-Pesch effect) is studied for an isolated single vortex for chiral
p-wave and s-wave superconducting phases. The effect of nonmagnetic impurities on the vortex core radius is numerically investigated
in the Born limit by means of a quasiclassical approach. It is shown that in the chiral p-wave phase the Kramer-Pesch effect
displays a certain robustness against impurities owing to a specific quantum effect, while the s-wave phase reacts more sensitively
to impurity scattering. This suggests chiral p-wave superconductors as promising candidates for the experimental observation
of the Kramer-Pesch effect. 相似文献
66.
Coupled simulation of BES-CFD and performance assessment of energy recovery ventilation system for office model 总被引:1,自引:0,他引:1
Thermal comfort and indoor air quality as well as the energy efficiency have been recognized as essential parts of sustainable
building assessment. This work aims to analyze the energy conservation of the heat recovery ventilator and to investigate
the effect of the air supply arrangement. Three types of mixing ventilation are chosen for the analysis of coupling ANSYS/FLUENT
(a computational fluid dynamics (CFD) program) with TRNSYS (a building energy simulation (BES) software). The adoption of
mutual complementary boundary conditions for CFD and BES provides more accurate and complete information of indoor air distribution
and thermal performance in buildings. A typical office-space situated in a middle storey is chosen for the analysis. The office-space
is equipped with air-conditioners on the ceiling. A heat recovery ventilation system directly supplies fresh air to the office
space. Its thermal performance and indoor air distribution predicted by the coupled method are compared under three types
of ventilation system. When the supply and return openings for ventilation are arranged on the ceiling, there is no critical
difference between the predictions of the coupled method and BES on the energy consumption of HVAC because PID control is
adopted for the supply air temperature of the occupied zone. On the other hand, approximately 21% discrepancy for the heat
recovery estimation in the maximum between the simulated results of coupled method and BES-only can be obviously found in
the floor air supply ventilation case. The discrepancy emphasizes the necessity of coupling CFD with BES when vertical air
temperature gradient exists. Our future target is to estimate the optimum design of heat recovery ventilation system to control
CO2 concentration by adjusting flow rate of fresh air. 相似文献
67.
Cliteur G.J. Hayashi Y. Haginomori E. Suzuki K. 《Dielectrics and Electrical Insulation, IEEE Transactions on》1998,5(6):843-849
We calculated the uniform dielectric breakdown field strength of SF6 gas over the temperature range of 300 to 3000 K. The local thermal equilibrium (ITE) composition of the dissociated gas is connected to the electron impact collision cross sections of the species SF6, F2, F and S. The critical reduced electric field strength of the composition is determined by a balancing electron generation and loss modeled by chemical reactions evaluated by the electron energy distribution function (EEDF) derived from the Boltzmann transport equation. At room temperature, pure SF6 has a critical reduced electric field strength of 362 Td. With increasing temperature and decreasing density we found a small decrease of this value, whereas at temperatures higher than 1500 K, dissociation starts to decrease the dielectric strength of the composition. Furthermore, we found that generation of electrons by (associative) detachment from F - starts to play an important role at temperatures >2500 K, where the critical field strength still has a value of 118 Td. This value is found to decrease rapidly afterwards with increasing temperature to the value of 38 Td at 3000 K. The calculated results agree very well with independently predicted values and measured data 相似文献
68.
M Kubo K Kikuchi K Nashiro T Kakinuma N Hayashi H Nanko K Tamaki 《Canadian Metallurgical Quarterly》1998,139(2):192-197
OBJECTIVE: Research has confirmed substantial links between OCD and AN. Not only are there psychopathological similarities between the two syndromes, but a marked neurochemical correspondence. Extensive exercising is a common feature of AN and also has relevance in its links with OCD. There is evidence from the exercise-induced weight-loss syndrome in animals that exercise and caloric restriction, in combination, tend to increase serotonergic activity in a synergistic manner. This syndrome has been proposed as a valid model of OCD as well as for AN. To date, little research has directly tested this theory in the human condition. METHOD: Fifty-three AN patients were categorized as high-level exercisers (N = 22) or moderate/nonexercisers (N = 31) based on the frequency of their physical activity over the year before assessment. RESULTS: Exercisers scored significantly higher on a measure of OC personality characteristics, OC symptomatology, and perfectionism--a personality factor associated with the development of Obsessive-Compulsive Personality Disorder. On the other hand, there were no group differences on other salient eating disorder characteristics such as body esteem, self-esteem, or weight preoccupation. There were also no differences in degree of emaciation as indicated by Body Mass Index. CONCLUSIONS: Findings suggest that among AN patients obsessional personality characteristics are linked to high-level exercising, and that exercising is associated with a greater degree of OC symptomatology. Results are discussed in the context of current theories of AN, OCD, and some biological mechanisms. 相似文献
69.
Tatsuhide Hayashi Masaki Asakura Mayu Kawase Masakazu Matsubara Yasuaki Uematsu Akimichi Mieki Tatsushi Kawai 《International journal of molecular sciences》2022,23(13)
This study aimed to induce bone-like tissue from immature muscular tissue (IMT) in vitro using commercially available recombinant human bone morphogenetic protein (rhBMP)-2, rhBMP-4, and rhBMP-7, and then implanting this tissue into a calvarial defect in rats to assess healing. IMTs were extracted from 20-day-old Sprague-Dawley (SD) fetal rats, placed on expanded polytetrafluoroethylene (ePTFE) with 10 ng/μL each of rhBMP-2, BMP-4, and BMP-7, and cultured for two weeks. The specimens were implanted into calvarial defects in 3-week-old SD rats for up to three weeks. Relatively strong radiopacity was observed on micro-CT two weeks after culture, and bone-like tissue, comprising osteoblastic cells and osteoids, was partially observed by H&E staining. Calcium, phosphorus, and oxygen were detected in the extracellular matrix using an electron probe micro analyzer, and X-ray diffraction patterns and Fourier transform infrared spectroscopy spectra of the specimen were found to have typical apatite crystal peaks and spectra, respectively. Furthermore, partial strong radiopacity and ossification were confirmed one week after implantation, and a dominant novel bone was observed after two weeks in the defect site. Thus, rhBMP-2, BMP-4, and BMP-7 differentiated IMT into bone-like tissue in vitro, and this induced bone-like tissue has ossification potential and promotes the healing of calvarial defects. Our results suggest that IMT is an effective tissue source for bone tissue engineering. 相似文献
70.
In switched reluctance motors (SRM), the flux waveforms are nonsinusoidal and different parts of the magnetic circuit have different waveforms. This paper presents a new approach of taking account of these flux waveforms in the calculation of core losses. Relations between the fluxes of different parts of the magnetic circuits are given in the form of matrix equations, where the fluxes are expressed in terms of normalized flux pulses. Rewriting the eddy-current loss term in the Steinmetz equation in terms of the square of dB/dt and combining it with the matrix equations, eddy-current losses for the complicated flux waveforms of the stator and rotor yokes are calculated. The effect of PWM is taken into account by considering the PWM voltage waveform as dB/dt. From the matrices, it is easy to count how many times full and minor hysteresis loops occur at each pole and yoke segment. The effect of the minor loop is taken into account based on experimental results. The proposed approach gives a systematic procedure for core loss calculation. The derived equations are simple and useful in the design of SRM 相似文献