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31.
Previous work has shown that male sorghum plant bugs, Stenotus rubrovittatus (Matsumura) (Heteroptera: Miridae), are more attracted to young virgin females than to old virgin females and are not attracted
to mated females. Therefore, we examined the effects of age and mating status on female sex pheromone levels. The pheromone
components, hexyl butyrate, (E)-hex-2-en-1-yl butyrate, and (E)-4-oxohex-2-enal, were collected from females in two different ways. First, the compounds were extracted from whole bodies
of each female and quantified by gas chromatography-mass spectrometry (GC-MS). Pheromone levels extracted from virgin female
bodies decreased with age. In females that had just mated, pheromone levels did not differ from those of virgin females, and
pheromone levels in mated females remained relatively constant up to 15 d after mating. This absence of change in pheromone
levels extracted from whole bodies of mated females is not congruent with previous reports of lack of male attraction to these
females. In a second method for pheromone recovery (adsorption on a PDMS-coated stir bar), GC-MS analysis showed that mated
females released lower amounts of pheromone components compared to those emitted by virgin females of the same age (4 d).
As was the case with whole body extracts, young virgin females (3 d) released higher amounts of pheromone components than
did old virgin females (8 d). The results suggest that male response in S. rubrovittatus is dictated more by the quantities of pheromone components released into the volatile headspace by females than by the quantities
present in the body. 相似文献
32.
Takuya Noguchi Toshihiro Shimada Takashi Chiba Masao Terada Tetsuya Hasegawa 《Diamond and Related Materials》2010,19(2-3):107-109
We have carried out very high temperature heat treatment at 1400–2700 °C of about 10 nm-thick amorphous carbon thin films deposited on refractory substrates MgO, Al2O3, and yttria-stabilized zirconia (YSZ) using pulsed laser deposition techniques. After the annealing, a few nanometer scale sp2 crystallization of the films and a large corrugation with a height of more than 1 μm were observed by Raman spectroscopy analysis and optical/atomic force microscopes, respectively. The corrugation is probably caused by the formation of gases at the film/substrate interface during the heat treatment. 相似文献
33.
Md. Zaved Hossain Khan Takuya Nakanishi Shigeki Kuroiwa Yoichi Hoshi Tetsuya Osaka 《Electrochimica acta》2011,(24):8657
The effect of surface modification of indium tin oxide (ITO) electrode on its potential response to tryptophan was investigated for ITO substrates with different surface roughness. It was found that a small difference in surface roughness, between ∼1 and ∼2 nm of Ra evaluated by atomic force microscopy, affects the rest potential of ITO electrode in the electrolyte. A slight difference in In:Sn ratio at the near surface of the ITO substrates, measured by angle-resolved X-ray photoelectron spectrometry and Auger electron spectroscopy is remarkable, and considered to relate with surface roughness. Interestingly, successive modification of the ITO surface with aminopropylsilane and disuccinimidyl suberate, of which essentiality to the potential response to indole compounds we previously reported, improved the stability of the rest potential and enabled the electrodes to respond to tryptophan in case of specimens with Ra values ranging between ∼2 and ∼3 nm but not for those with Ra of ∼1 nm. It was suggested that there are optimum values of effective work function of ITO for specific potential response to tryptophan, which can be obtained by the successive modification of ITO surface. 相似文献
34.
Katsunori Takeda Tetsuo Hattori Tetsuya Izumi Hiromichi Kawano Shinichi Masuda 《Artificial Life and Robotics》2010,15(4):421-424
Recently, remote monitoring camera systems have been widely used for security. In such systems, one important function is
that the system automatically detects any change in the scenes from the monitoring cameras. In wireless remote monitoring
camera systems, the images of the scenes are generally transmitted as compressed data (e.g., JPEG file), because of the capacity
of the wireless channel. This article shows the automated detection of the change point in time-series data of compressed
JPEG file quantity (Kbytes) from the monitoring camera by applying the sequential probabilistic ratio test (SPRT) and the
Chow test, which is well known as a standard method for detecting structural change in time-series data. 相似文献
35.
A self-assembled monolayer (SAM) of l-homocysteine (l-Hcy) formed on the surface of a gold-deposited gate of a field effect transistor (FET) was used to differentiate between enantiomers of amino acids, for which the formation of diastereomeric metal complexes is fundamental for chiral discrimination. Here, we focus our attention on the dependence of the FET response on the analyte amino acids, the central metal ions involved in complex formation, and the solution pH. Using the l-Hcy SAM-modified gate with added Cu(II), notable negative FET responses were enantioselectively observed for the l-enantiomers of alanine (Ala), phenylalanine, and tryptophan, whereas differences in the FET responses between enantiomers were negligible for asparagine and aspartic acid. Regarding the enantioselectivity for Ala, the addition of Cu(II) was demonstrated to show higher selectivity as compared to other metal ions such as Co(II) and Ni(II). Moreover, for the addition of l-Ala and Cu(II), a particularly strong negative FET response was observed at pH 5.5. 相似文献
36.
Atsushi Ohma Tetsuya Mashio Kazuyuki Sato Hiroshi Iden Yoshitaka Ono Kei Sakai Ken Akizuki Satoshi Takaichi Kazuhiko Shinohara 《Electrochimica acta》2011,(28):10832
The biggest issue that must be addressed in promoting widespread use of fuel cell vehicles (FCVs) is to reduce the cost of the fuel cell system. Especially, it is of vital importance to reduce platinum (Pt) loading of catalyst layers (CLs) in the membrane electrode assembly (MEA) of a proton exchange membrane fuel cell (PEMFC). In order to lower the Pt loading of the MEA, mass transport of reactants related to the performance in high current density should be enhanced significantly as well as kinetics of the catalyst, which can result in the better Pt utilization and effectiveness. In this study, we summarized our analytical approach and methods for reduction of Pt loading in CLs. Microstructure, mass transport properties of the reactants, and their relation in CLs were elucidated by applying experimental analyses and computational methods. A simple CL model for I–V performance prediction was then established, where experimentally elucidated parameters of the microstructure and the properties in CLs were taken into account. Finally, we revealed the impact of lowering the Pt loading on the transport properties, polarization, and the I–V performance. 相似文献
37.
Shinichi Itoh Kenji UenoRyuji Ohkubo Hidenori SagehashiYoshisato Funahashi Tetsuya Yokoo 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,654(1):527-531
We investigated the irradiation properties of the components of a T0 chopper. The organic materials in the rotor bearing grease, the magnetic fluids in seals, and the rubber in the timing belt, as well as the semiconductor materials in the rotation sensor and motor encoder, were all irradiated with high-energy γ-rays up to 100 kGy. No significant damage that shortens the lifetime of a T0 chopper was observed for the mechanical components. However, the semiconductor components were damaged by the irradiation. For the rotation sensor system detecting the rotor phase, the signal from a marker on the rotor shaft was transmitted outside the shielding by an optical fiber with radiation-proofing and the electrical circuits were removed from the beamline shielding. The lifetime of the motor encoder possibly meets the requirement for the maintenance period of the T0 chopper. 相似文献
38.
Tetsuya Yamamoto Tomohiko Shinya Kunihiro Fukui Hideto Yoshida 《Advanced Powder Technology》2011,22(2):294-299
This study gives fundamental knowledge on the particle classification performance by centrifugal separator.It is found that the cut size of a centrifugal separator decreases as the rotational speed increases and the liquid flow rate decreases. Fitting our experimental results with the theory, they agree with each other at high flow rate. However, the difference between them generates at low flow rate. This is because dead spaces are generated in the centrifugal separator at the low flow rate. Also, the computer simulation of the fluid behavior in the centrifugal separator can find the decrease of the velocity near the wall under the low flow rate, which suggests the possibility of the formation of dead spaces in the separator. 相似文献
39.
Sn2+-incorporated potassium titanate (K2Ti6O13) nanoribbons were prepared by a facile acid-free ion-exchanged method in a dehydrated methanol solution at room temperature. XRD patterns suggested that K2Ti6O13 (KTO) and Sn2+-incorporated KTO (SKTO) are well crystallized with monoclinic phase structures. The mole ratio of incorporated Sn2+ to K+ in SKTO was estimated to be 2. X-ray photoelectron spectrum showed that the Sn species of SKTO consisted of 90% of Sn2+ and 10% of Sn4+, suggesting that part of Sn2+ was oxidized to Sn4+ in the incorporation process. The band gap of SKTO was 0.7 eV narrower than that of KTO, which was derived from lift of the top of the valence band due to the hybridization of Sn5s and O2p orbitals. The SKTO nanoribbons showed remarkable photocatalytic activities for H2 evolution and rhodamine B degradation under visible light irradiation (λ ≥ 420 nm). The photocatalytic mechanism and durability were studied in detail. The advantage of this acid-free ion-exchange method is ease of ion-exchange of K+ with H+ and maintenance of the integrity of the 1D nanoribbon structures. This method can be applied to preparation of other Sn2+-incorporated compounds with special nanostructures. 相似文献
40.
The effect of the 2008 Iwate-Miyagi Nairiku earthquake (MJ 7.2), Japan on the Aratozawa dam, which is a 74.4 m high rockfill dam with a central clay core located in the area, was studied with a main focus on the change in the vibration period, shear wave velocity, shear modulus, and pore-water pressure. In a vertical section of the central part of the dam, three sets of 3-component accelerometers and 15 pore water pressure meters were installed. During the main shock, the acceleration exceeded 10 m/s2 at the gallery, inducing large shear strains in excess of 10-3 and a sudden build-up of the excess pore water pressure in the core. Due to the large strains, the shear wave velocity and shear modulus showed a significant decrease from their initial values and the vibration period was elongated. The decreased shear wave velocity gradually recovered toward the end of the main shock, and continued to recover with the passage of time. The full recovery of the wave velocity was found to take at least one year, while the dissipation of the excess pore water pressure proceeded more quickly than the recovery of the wave velocity. 相似文献