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This paper is concerned with the theoretical treatment of the steady-state thermoelastic problem of a functionally graded cylindrical panel due to nonuniform heat supply in the circumferential direction. The thermal and thermoelastic constants of the cylindrical panel are expressed as power functions of the radial coordinate. We obtain the exact solution for the two-dimensional temperature change in a steady state, and thermal stresses of a simple supported cylindrical panel under the state of plane strain. Some numerical results are shown in figures and tables. Furthermore, the influence of the nonhomogeneity of the material, the radius ratio and the span angle upon the temperature change, displacements and stresses is investigated. 相似文献
44.
Toshifumi Yui Kiego Miyawaki Yoshinobu Kawano Kozo Ogawa 《Journal of carbohydrate chemistry》2013,32(8):905-914
ABSTRACT Miniature crystal models of six small carbohydrates were examined using the PM3 semiempirical quantum mechanics method. The minicrystal structures, consisting of 27 sugar residues, were optimized by the combined procedure of partial optimization and reconstruction of the model, while maintaining the original crystal symmetries. All of the minicrystals were successfully optimized without exhibiting a great increase in an energy at any reconstruction step. Some minicrystals showed a prolonged behavior of optimization cycles. A major source of structure change appeared to arise from hydroxyl group rotations wherein the largest movements mostly occurred in an early optimization stage. No significant deformations in geometry of either residues or hydrogen bonds were observed in the final minicrystal structures. The thermodynamic values calculated for the optimized minicrystals were in reasonably good agreement with the literature data. The present study indicated that the PM3 semiempirical method successfully predicted the basic features of intermolecular hydrogen bonding involved in a condensed system. 相似文献
45.
A bistable optical device was demonstrated by using the longitudinal mode hopping of the laser diode and the narrow transmission spectrum of an interference filter. The device is capable of converting changes in the wavelength of the laser diode into changes in intensity by transmitting it through the filter. Exclusive OR operation was observed with the use of triple signal outputs. In addition, an optical switch-off phenomenon was confirmed by directly injecting a pulse 500 ps wide into an external dye laser. 相似文献
46.
Fujii S Mochizuki M Aono K Hamasaki S Murakami R Nakamura Y 《Langmuir : the ACS journal of surfaces and colloids》2011,27(21):12902-12909
Polystyrene (PS) latex particles carrying pH-responsive poly[2-(diethylamino)ethyl methacrylate] (PDEA) hair (PDEA-PS particles) were synthesized by dispersion polymerization and characterized in terms of diameter, diameter distribution, morphology, chemical composition, surface chemistry, and pH-response using scanning electron microscopy (SEM), elemental microanalysis, (1)H nuclear magnetic resonance spectroscopy, the laser diffraction method, and zeta potential measurements. The hairy particles can act as pH-responsive stabilizers of aqueous foams by adsorption at the air-water surface. Above pH 8.0, where particles have nonprotonated PDEA hair, which is relatively hydrophobic, particle-stabilized foams are stable for at least 1 month. Optical microscopy and SEM confirmed that flocculated PDEA-PS latex particles were adsorbed at the air-water interface and stabilized the aqueous foams. At pH 6.1 and 7.1, relatively stable foams can be prepared that remain stable for at least 24 h. SEM studies indicated that the PDEA-PS particles were adsorbed at the air-water interface as a monolayer at pH 6.1. At pH 5.1 and 3.1, where the particles have cationic water-soluble PDEA hairs with hydrophilic character, no foam was formed. Rapid defoamation can be induced by lowering the solution pH; the addition of acid caused the in situ protonation of 2-(diethylamino)ethyl methacrylate residues, which impart water-soluble hydrophilic character to the PDEA hair, and the PDEA-PS particles desorbed from the air-water interface. The foaming and defoaming cycles could be repeated at least five times. 相似文献
47.
Tachi T Hase T Okamoto Y Kaji N Arima T Matsumoto H Kondo M Tokeshi M Hasegawa Y Baba Y 《Analytical and bioanalytical chemistry》2011,401(7):2301-2305
Microchip analysis is a promising method for therapeutic drug monitoring. This led us to evaluate a microchip-based fluorescence
polarization immunoassay (FPIA) system for point-of-care testing on patients being treated with theophylline. The sera were
collected from 20 patients being treated with theophylline. Fluorescence polarization was measured on the microchip and theophylline
concentrations in serum were obtained. Regression analysis of the correlations was done between the results given by the microchip-based
FPIA and the conventional cloned enzyme donor immunoassay (CEDIA), and between the results given by the microchip-based FPIA
and the conventional particle-enhanced turbidimetric inhibition immunoassay (PETINIA). We successfully carried out a quantitative
analysis of theophylline in serum at values near its therapeutic range in 65 s. The results obtained by the microchip-based
FPIA correlated well with CEDIA and PETINIA results; the correlation coefficients (R
2) were 0.986 and 0.989, respectively. The FPIA system is a simple and rapid method for point-of-care testing of drugs in serum,
and its accuracy is the same as the conventional CEDIA and PETINIA. It is essential to use real samples from patients and
to confirm good correlations with conventional methods for a study on the realization of microchip. 相似文献
48.
Urea compounds are useful anion sensors due to their hydrogen-bonding capabilities. We investigated the emissive properties of complexes consisting of urea-anthracene (nPUA, n = 1, 2) host compounds and acetate anions held as guests through intermolecular hydrogen bonding. The kinetics of a new emission band formed by conformational changes in the excited singlet state were revealed. The new band is thought to arise from a charge-transfer interaction between the anthracene and urea moieties after intermolecular hydrogen-bond reconfiguration in the excited state, with rate constants of 2.4 × 10(9) and 4.0 × 10(7) s(-1) for 1PUA and 2PUA, respectively. 相似文献
49.
Hossain MZ Mukai K Yamashita Y Kawai H Yoshinobu J 《Chemical communications (Cambridge, England)》2011,47(37):10392-10394
The anisotropic correlation between buckled dimers on Si(100) was investigated by scanning tunneling microscopy. A bidentate ligand molecule was used to pin two neighboring dimers at 300 K. The chemically pinned dimer induces antiferromagnetic interaction along the dimer rows. Observed results agree well with Monte-Carlo simulations semi-quantitatively. 相似文献
50.
Mohammad Jabasini Ashraf A Ewis Feng Xu Guichen Ping Maged Fouad Toshikatsu Shinka Yutaka Nakahori Mitsuru Ishikawa Yoshinobu Baba 《Analytical sciences》2005,21(12):1537-1539
For the diagnosis of unexplained male infertility a multiplex PCR for 6 markers, which are well-known as candidate genes for studying male infertility and located on the human Y-chromosome, has been designed. The multiplex PCR products have been separated on a 12 channel microchip electrophoresis system, which can analyze different samples simultaneously. By combining the technologies of multiplex PCR with multichannel microchip electrophoresis, the number of the DNA markers that can be screened simultaneously is increased to be 72 marker (12 x 6) in a single run while the electrophoresis analysis time is reduced to be only 180 s. 相似文献