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101.
The electron temperature (Te) in an electron cyclotron resonance plasma is clarified to depend on the spatial profiles of the microwave-power absorption by both the electromagnetic-waves measurement and the simulation of microwave power absorption. It is found that Te is controlled by varying the magnetic field configuration and/or the microwave frequency since the power absorption profile is influenced by the effective resonance width. In fact, Te is observed to decrease with decreasing the magnetic field gradient at the resonance point for N2, Ar and O2/Ar plasma. 相似文献
102.
This study describes a new method of experimental design to obtain a response surface of buckling load of laminated composites. Many evaluations for genetic algorithms for stacking sequence optimizations require high computational cost. That evaluation cost can be reduced by an approximation using a response surface. For a response surface for stacking sequence optimizations, lamination parameters are adopted as variables of the approximation function of the entire design space instead of ply angles for each ply. This study presents, proposes and investigates a new method of experimental design in detail. For most analytical tools, stacking sequences is demand as input data and lamination parameters cannot be applied directly to the tools. Therefore, the present study proposes and applies a new D-optimal set of laminates to the stacking sequence optimizations of the problem of maximization of buckling load of a composite cylinder. The new experimental design is a set of stacking sequences selected from candidate stacks using D-optimality. Consequently, the D-optimal set of laminates is shown to be effective for design of experiments of response surfaces for maximization of the buckling load of composite structures. 相似文献
103.
Akira Masutani Tony Roberts Bettina Schüller Akio Yasuda Akira Sakaigawa Graham Cross David Bloor 《Journal of the Society for Information Display》2004,12(3):301-307
Abstract— A novel preparation method for dichroic dye‐doped polymer‐dispersed liquid crystals has been developed. This was achieved by creating a porous polymer matrix first by washing out the liquid crystal from a polymer‐dispersed liquid crystal (PDLC), which is then refilled with dye‐doped liquid crystal. Optimizing the liquid crystal used in the refilling results in decreased turn‐on voltage and faster response time. Poster‐standard reflectivity and newspaper‐standard contrast was demonstrated with a 3.8‐in. QVGA reflective TFT display with a drive voltage of 10 V. 相似文献
104.
Application of an ultrahigh-resolution scanning electron microscope (UHS-T1) to biological specimens
Keiichi Tanaka Akira Mitsushima Yuzuru Kashima Takashi Nakadera Hitoshi Osatake 《Microscopy research and technique》1989,12(2):146-154
In 1985 we developed an ultrahigh-resolution scanning electron microscope with a resolution of 0.5 nm. It is equipped with a field emission gun and an objective lens with a very short focal length. In this study we report a survey of some different preparation techniques and biological specimens using the new scanning electron microscope. Intracellular structures such as cell organelles were observed surprisingly sharper than those observed by ordinary scanning electron microscopes. However, at magnifications over 250,000 X, platinum particles could be discerned as scattered pebbles on the surface of all structures in coated materials. Using an uncoated but conductively stained specimen, we successfully observed ribosomes on a rough endoplasmic reticulum at a direct magnification of 1 million. In these images some protrusions were recognized on the ribosomes. Ferritin and immunoglobulin G were used as samples of biological macromolecules. These samples were observed without metal coating and conductive staining. The ferritin particles appeared as rounded bodies without any substructure on the surface and immunoglobulin G as complexes of three-unit bodies. In the latter the central body might correspond to the Fc fragment and two side ones to Fab fragments. We assume that ultrahigh-resolution scanning electron microscopy is an effective means for observation of the cell fine structures and biological macromolecules. It will open a new research field in biomedicine. 相似文献
105.
Takeda K Mori H Yamaguchi A Ishimoto H Nakamura T Kuriki S Hozumi T Ohkoshi S 《The Review of scientific instruments》2008,79(3):033909
We have developed a high temperature superconductor (HTS) micrometer-sized dc superconducting quantum interference device (SQUID) magnetometer for high field and high temperature operation. It was fabricated from YBa2Cu3O7-delta of 92 nm in thickness with photolithography techniques to have a hole of 4x9 microm2 and 2 microm wide grain boundary Josephson junctions. Combined with a three dimensional magnetic field coil system, the modulation patterns of critical current Ic were observed for three different field directions. They were successfully used to measure the magnetic properties of a molecular ferrimagnetic microcrystal (23x17x13 microm3), [Mn2(H2O)2(CH3COO)][W(CN)8]2H2O. The magnetization curve was obtained in magnetic field up to 0.12 T between 30 and 70 K. This is the first to measure the anisotropy of hysteresis curve in the field above 0.1 T with an accuracy of 10(-12) J T(-1) (10(-9) emu) with a HTS micro-SQUID magnetometer. 相似文献
106.
Relationship between particle erosion and lamellar microstructure for plasma-sprayed alumina coatings 总被引:5,自引:0,他引:5
The lamellar structure determines mechanical properties of a thermal spray coating. A model for the erosion of thermally sprayed ceramic coatings resulting from the debonding of flattened ceramic particles is proposed based on the examination of the erosion mechanism. The relationship between erosion rate and microstructural parameters is established both experimentally and theoretically to reveal main lamellar structural parameters controlling erosion of thermally sprayed ceramic coating. The microstructural parameters include the mean bonding ratio between lamellae and thickness of the lamellae. The erosion rate of plasma-sprayed Al2O3 coatings was measured at impact angle of 90° under the fixed erosion test conditions. The correlation of theoretical model with the observed structural parameters and erosion data of alumina coatings was examined. It is revealed that the theoretical relationship agreed well with the observed relation. The results clearly revealed that the erosion of plasma-sprayed ceramic coating was inversely proportional to the mean lamellar bonding ratio. The influences of spray parameters on erosion effected mainly through their influences on the lamellar bonding. The erosion resistance of a thermally sprayed ceramic coating was controlled by coating fracture toughness. 相似文献
107.
In order to observe intracellular structures by scanning electron microscopy, excess cytoplasmic matrix must be removed from the fractured surface of cells. Previously we reported an Osmium-DMSO-Osmium method devised for this purpose. This method is very effective in revealing intracellular structures, but requires osmium tetroxide for initial fixation with some consequent disadvantages. In the present study, a revised Osmium-DMSO-Osmium method is reported, in which an aldehyde mixture is used as the initial fixative instead of osmium tetroxide. As fixation is carried out by perfusion in this revised method, better preservation of fine structures is achieved than by the original method, especially in the central nervous tissue which tends to suffer from post-mortem degeneration. Moreover this method can be applied to cytochemical studies of intracellular structures with a scanning electron microscope (SEM). In this study, acid phosphatase of lysosomes is demonstrated in a coloured SEM micrograph. 相似文献
108.
Kengo Akaho Takashi Nakagawa Yoshihisa Yamaguchi Katsuya Kawai Hirokazu Kato Shogo Nishida 《Electrical Engineering in Japan》2012,180(2):43-54
Car navigation systems play a prominent role in road traffic safety and traffic regulation. However, it is necessary to improve the route guidance of car navigation systems so that they accurately and quickly recognize small differences in location. Thus, to increase the ease of understanding and safety of car navigation systems, navigation systems based on augmented reality have been proposed for providing guidance at road intersections. We are currently developing a car navigation system based on augmented reality, called AR‐Navi. We investigated designs for the display of road intersection guidance that can be easily understood even when limited information is available and proposed a “best shot” display method that does not use moving images. In addition, we implemented a prototype system that includes these methods and conducted driving experiments on public roads to evaluate the ease of understanding and safety of AR‐Navi. Using the evaluation results, we confirmed that the ease of understanding and safety is similar in the case of AR‐Navi and CG‐Navi. We also clarified the characteristics of AR‐Navi. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 180(2): 43–54, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22278 相似文献
109.
Majid Mohammadi Seid Ahmad Jenabali Jahromi Sirus Javadpour Akira Kobayashi Kurosh Shirvani 《Oxidation of Metals》2012,78(1-2):17-30
Conventional and gradient CoNiCrAlYSi coatings were produced by using low vacuum plasma spray and an additional step of diffusional over aluminizing (pack cementation) techniques on an Inconel-738 substrate. Hot corrosion of these coatings was investigated using Na2SO4–20wt%NaVO3 molten salt at 880?°C for 800?h. Hot corrosion rate was determined by measuring the weight gain of the specimens at regular intervals for a duration of 20?h. X-ray diffraction, field emission scanning electron microscopy and electron probe micro analysis techniques were used to determine the nature of phases, investigation of the thermally grown oxide, examination of the surface attack and determination of the elemental distribution. The gradient coating showed better performance by re-healing alumina scale due to its possession of more β phase as Al reservoir. Results indicated that pack cementation process caused an increase in amount of aluminum-rich β phase and better hot corrosion properties of gradient coatings owing to the Al enrichment in the outer layer and rapid formation of protective oxide on the surface. 相似文献
110.
In vivo measurement of swallowing by monitoring thyroid cartilage movement in healthy subjects using thickened liquid samples and its comparison with sensory evaluation 下载免费PDF全文