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21.
Ryohei Tsuda Sayaka Kaino Hisashi Kokubo Shin-Ichiro Imabayashi Masayoshi Watanabe 《Colloids and surfaces. B, Biointerfaces》2007,56(1-2):255-Optics
Redox properties of phenothiazine-labeled poly(ethyl glycidy ether)-block-poly(ethylene oxide) (PT-EGEn-b-EOm) are reversibly changed by core-shell micelle formation. In the temperature range higher than the critical micellization temperature (cmt), the anodic potential of PT group positively shifts and concomitantly its anodic current decrease, or levels off compared to those of the reference polymer PT-EOm without the thermo-responsive EGEn segment. The former alteration is caused by incorporation of hydrophobic PT groups into a core of the micelle and the latter by the decrease in the diffusion coefficient of PT groups due to formation of the core-shell micelles. The cmt value and the temperature-dependent alteration in the redox properties strongly depend on the polymer structure, especially the length of thermo-responsive EGEn segment. The electrochemically determined hydrodynamic radii of the polymer aggregates seem to be overestimated, compared to the values reported for the aggregates of other thermo-responsive polymers with similar molecular weights, implying the presence of electrochemically inactive PT groups in the copolymers having longer thermo-responsive segments. 相似文献
22.
A model for the flow of a fluid through a channel with parallel plates is investigated. The channel is narrow, so that the lubrication approximation may be applied. The channel walls are maintained at a constant temperature. Shear heating effects are included and the fluid viscosity decreases exponentially with temperature. When the flow is driven solely by shear stress or imposed velocity at the top, analytical progress is possible. When pressure gradient also drives the flow the problem is solved numerically. 相似文献
23.
Microwave Activation of Processes in Mesopores: The Thiourea Electrooxidation at Mesoporous Platinum
《Electroanalysis》2006,18(8):793-800
In situ microwave activation is applied to the electrochemical oxidation of thiourea at low surface area (polished polycrystalline) and at high surface area (electrodeposited mesoporous platinum coated) platinum microelectrodes. The one electron oxidation of thiourea to formamidine disulfide is monitored as a function of the different activation parameters. In the absence of microwaves (ambient temperature, low mass transport) increasing the surface area (roughness) increases the thiourea oxidation response predominantly due to adsorption effects. In the presence of high microwave intensities, high mass transport and thermal effects further increase the oxidation current at mesoporous platinum. The most effective thickness of the mesoporous platinum film for the thiourea oxidation process is estimated as 3 μm independent of electrode diameter, temperature, or mass transport effects. 相似文献
24.
25.
In this paper, the possibility of using the gradients of the temperature and of the internal parameters as additional state variables in Continuum Thermodynamics is considered. The expressions of the two principles are discussed and Clausius–Duhem inequality is derived under an appropriate statement of the internal entropy production. Several formulations are proposed and compared to existing results in the literature. To cite this article: P. Ireman, Q.S. Nguyen, C. R. Mecanique 332 (2004). 相似文献
26.
Zhang ping School of Information Electrical Engineering of Hunan University of Science Technology Hunan Xiangtan 《科技信息》2008,(17)
介绍了以三菱FX0NPLC为核心的温度控制系统在电镀生产线中的应用。简述了温度控制原理,论述了控制系统的设计方案及其软硬件的实现方法。实践表明该方法简单易行,适应性好,可靠性高。 相似文献
27.
E.V. Jansson 《Applied Acoustics》2004,65(12):1197-1205
Good violins have a broad hill in the 2-3 kHz range of their frequency response. This hill has previously been attributed to the first in-plane resonance of the violin bridge. Experiments prove, however, that the hill is the result of two forces acting in opposite directions at the bridge feet. The experiments reported here show that the hill can be “tuned” by altering the distance between the bridge feet. It can be tuned both in terms of frequency and level but the properties of the violin cannot be neglected. 相似文献
28.
A novel measurement method of temperature based on the phenomena that the phase difference between principle polarization states in the optical retarder is function of temperature is described. The polarization state of optical beam is changed as it passes through the optical retarder, which depends on the temperature. The temperature of optical retarder is determined by comparison of the power difference between principal polarization states. We demonstrate successfully the temperature measurement by using a polarization maintaining fiber as the optical retarder. With a 100 mm length of the fiber optic retarder, the change rate of phase difference on temperature was 0.236 rad/°C and the measurement error was ±0.038°C over the temperature range of −2.6 – +3.4°C. With a 11.5 mm length of the fiber optic retarder, the change rate of phase difference on temperature was 0.021 rad/°C and the measurement error was ±0.79°C over the temperature range of −8.5 – +86.5°C. 相似文献
29.
A simple and accurate algorithm (phase scanning method) is proposed for 3D surface contouring and dynamic response determination of a vibrating object. A sinusoidal fringe pattern is projected onto a low-frequency vibrating object by a programmable liquid crystal display projector. The fringe patterns are captured by a high-speed CCD camera with a telecentric gauging lens. Phase values are evaluated point by point using phase scanning method. From the phase values of each point on the object, the contour of the specimen at different instants of vibration can be retrieved. In this paper, a small vibrating coin is used to demonstrate the validity of the method and the experimental results are compared with test results on a stationary coin using four-step phase shifting and fast Fourier transform methods. The technique is especially useful in applications where the vibrating object has a complicated shape. 相似文献
30.
A mathematical model of laser beam treatment of double layer alloys (Ni/Fe, Al/Fe and Cr/Fe systems) describing the effect of laser beam on different physical and geometrical parameters of coated layer system has been adapted. The numerical solutions of the non-homogeneous heat-transport differential equation could estimate the temperature of the treated region.The suggested model allows investigation of the temperature distribution as a function of treated surface and laser parameters. The physical parameters of the treated materials were taken as functions of temperature due to the change in the temperature of the treated double layer materials. 相似文献