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41.
42.
Ion behavior confined in extended nanospace (10(1)-10(3) nm) is important for nanofluidics and nanochemistry with dominant surface effects. In this paper, we developed a new measurement technique of ion distribution in the nanochannel by super-resolution-laser-induced fluorescence. Stimulated emission depletion microscopy was used to achieve a spatial resolution of 87 nm higher than the diffraction limit. Fluorescein was used for ratiometric measurement of pH with two excitation wavelengths. The pH profile in a 2D nanochannel of 410 nm width and 405 nm depth was successfully measured at an uncertainty of 0.05. The excess protons, showing lower pH than the bulk, nonuniformly distributed in the nanochannel to cancel the negative charge of glass wall, especially when the electric double layer is thick compared to the channel size. The present study first revealed the ion distribution near the surface or in the nanochannel, which is directly related to the electric double layer. In addition, the obtained proton distribution is important to understand the nanoscale water structure between single molecules and continuum phase. This technique will greatly contribute to understanding the basic science in nanoscale and interfacial dynamics, which are strongly required to develop novel miniaturized systems for biochemical analysis and further applications. 相似文献
43.
Three diamensional (3D) measurement method by Scanning Electron Microscope (SEM) has already been proposed by using the principle
of shadow moiré. In the method, the image of original grid in shadow moiré image must be clearly removed in fringe analysis
process in order to perform high resolution analysis. A new method based on the principle of projection moiré is proposed
to solve the trouble concerning the grid. In this paper, the mechanism of producing some shadows of grid on the surface of
the object by back scattering electron beam in the new method is discussed. Fringe image as shadow of grid is analyzed by
Wavelet transform. The precise 3D measurement is realized by using the phenomenon of shadows of grid. Furthermore, a 3D micro
structure on the head of a hard disk is measured. From the comparison of results obtained by Atomic Force Microscope (AFM),
it is confirmed that the proposed method has high-resolution power(about 20nm). 相似文献
44.
Iwata Y. Momodomi M. Tanaka T. Oodaira H. Itoh Y. Nakayama R. Kirisawa R. Aritome S. Endoh T. Shirota R. Ohuchi K. Masuoka F. 《Solid-State Circuits, IEEE Journal of》1990,25(2):417-424
A high-density, 5-V-only, 4-Mb CMOS EEPROM with a NAND-structured cell using Fowler-Nordheim tunneling for programming is discussed. The block-page mode is utilized for high-speed programming and easy microprocessor interface. On-chip test circuits for shortening test time and for evaluating cell characteristics yield highly reliable EEPROMs. The NAND EEPROM has many applications for microcomputer systems that require small size and large nonvolatile storage systems with low power consumption 相似文献
45.
46.
Bruce A. Julian Hitoshi Suzuki Goce Spasovski Yusuke Suzuki Yasuhiko Tomino Jan Novak 《Proteomics. Clinical applications》2009,3(9):1023-1028
Chronic kidney disease accounts for a significant portion of many national health-care budgets. In this viewpoint, we highlight recent advances in urinary proteomic analyses that potentially may soon enhance the care of afflicted patients. To achieve this goal, cooperation of interdisciplinary teams from around the world will be vital, so as to standardize methodology for preparation urine samples and technical aspects of the analyses, and for better application of results. These collaborative activities will facilitate translational research in kidney diseases. 相似文献
47.
48.
Hiroi Masato Hojo Masayuki Hashimoto Yukio Abe Yoshikazu Dote Yasuhiko 《Industrial Electronics, IEEE Transactions on》1986,(2):110-113
A methodology of discontinuous feedback and continuous feedforward control is developed to achieve accurate decoupled tracking in a class of nonlinear, time varying systems in the presence of disturbances, parameter variations and nonlinear dynamic interactions. The method is based on an improved variable structure control with a sliding mode. 相似文献
49.
Improvement of partial discharge (PD) resistance of epoxy resin by using sulfur-containing additives
Yasuhiko Kako Shigetaka Watanabe Yutaka Higashimura Kenji Matsunobu 《Electrical Engineering in Japan》1994,114(7):1-11
In the field of high-voltage engineering, it has been desired for a long time to improve the internal PD resistance of epoxy resin without lowering other properties. Recently, the authors discovered that some sulfur compound as curing agents or simple additives improved the PD resistance of rubber markedly, and here an attempt has been made to apply this fact to the case of epoxy resin. As was expected, some sulfur compounds containing SS-bond suppress the deterioration of epoxy resin due to internal partial discharges, and the larger the molecular weight of organic group combining the SS-bond, the longer the effective life of additives. Moreover, to make full use of these additives, it is very important to restrict moisture in the insulation systems. From this study, the authors have proposed the chemical formulation of the suppressive effect of additives for deterioration of epoxy resin due to internal partial discharges. 相似文献
50.
Five sterylglycosides (acylmono-, mono-, di tri- and tetraglycosylsterol) and a saponin were isolated from Adzuki beans and
characterized. In the glycosylsterols, the principal component sterols were sitosterol and stigmasterol; the major sugar component
was glucose. The glucose units were shown to be linked by β1,6-bonds. The three oligoglycosylsterols were shown to be gentiobiosylsterol,
gentiotriosylsterol and gentiotetraosylsterol; the latter two are novel sterylglycosides. The saponin was identified as glucopyranosyl-(β1→2)-glucopyranurosyl-(β1→3′)-soyasapogenol
B (Azukisaponin I) which had previously been found in Adzuki beans. 相似文献