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171.
172.
Poly(styrene‐co‐butyl methacrylate) and poly(styrene‐co‐butyl acrylate) latices were prepared by emulsion polymerization with alkali‐hydrolyzable and nonhydrolyzable cationic emulsifiers and were used as a dispersant and binder for waterborne carbon black (CB) paint. CB was dispersed in the latex solutions and then coated on filter paper pretreated with dilute aqueous Na2CO3 under mild conditions. The styrene (St)‐rich rigid copolymer latices easily dispersed the CB but fixed a little amount of the pigment on the paper surface. In contrast, the methacrylate‐ and acrylate‐rich soft latices tended to increase the adhesibility on it. We also demonstrated that the hydrolyzable‐emulsifier‐containing latices always had a higher adhesibility than the nonhydrolyzable‐emulsifier‐containing ones. Thus, the hydrolyzable‐emulsifier‐containing latices with an appropriate St content had the highest paintability, rapid adhesion, quick drying, reduced fading, superior fastness, and so on. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3869–3873, 2013  相似文献   
173.
A gliding arc is a plasma that can be operated at atmospheric pressure and applied for plasma surface treatment for adhesion improvement. In the present work, glass-fibre-reinforced polyester plates were treated using an atmospheric pressure gliding arc discharge with an air flow to improve adhesion with a vinylester adhesive. The treatment improved wettability and increased the polar component of the surface energy and the density of oxygen-containing polar functional groups at the surfaces. Double cantilever beam specimens were prepared for fracture mechanics characterisation (fracture resistance as a function of nominal mode mixity) of the laminate adhesive interface. It was found that gliding arc treatment significantly increases the interfacial fracture energy and fracture resistance in comparison with a standard peel ply treatment, although the mixed mode fracture energy of the gliding arc treated specimen was not as high as that of the laminate itself.  相似文献   
174.
Atmospheric pressure plasma processing has attracted significant interests over decades due to its usefulness and a variety of applications. Adhesion improvement of polymer surfaces is among the most important applications of atmospheric pressure plasma treatment. Reflecting recent significant development of the atmospheric pressure plasma processing, this work presents its fundamental aspects, applications, and characterization techniques relevant to adhesion.  相似文献   
175.
176.
We present a theoretical model to incorporate the quantum mechanism of two‐photon transitions into macroscopic operations. The two‐photon transition is described as a two‐step interband–intraband transition within the one‐band envelope‐function framework and is coupled with drift–diffusion as well as the potential distribution. In0.53Ga0.47As/InP superlattices (SLs) are chosen as the initial candidate to simulate intermediate band solar cell operation. In this type of structure, the absorption spectrum of interband and intraband transitions is asymmetric and strongly depends on device structure and operating conditions. Our results also reveal that the intraband transition dominates the detailed balance. Both the intermediate band (IB) configuration and the conversion efficiency are determined by the SL structure. Only well‐designed SLs can form the appropriate IB. Furthermore, an efficiency contour plot has been calculated to guide quantum design: the peak efficiency is 45.61% when the well thickness is 4 nm and the barrier thickness is 2 nm. As the well or barrier thickness increases to 10 nm, the absorption peak of the intraband transition gradually redshifts and narrows, so the efficiency correspondingly decreases to below 40%. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
177.
The optical properties of π-conjugated polymer films based on poly(p-phenylene vinylene) (PPV) units under a wet condition were studied. We succeeded in producing multimode laser emission under a wet condition from cylindrical microcavities with a polymer thin film fabricated onto the inner surface of an optical capillary tube, which was filled with cyclohexane. Furthermore, lasing spectral modulation was demonstrated with the polymer laser. We discuss the lasing spectral modulation by taking the change in refractive index into consideration.  相似文献   
178.
For nonlinear thermal power plants whose dynamics vary with load demand, a load-dependent exponential ARX (Exp-ARX) model, which can effectively describe the nonlinear properties of the plants, is presented. The Exp-ARX model requires only off-line identification. Based on the model, a constrained multivariable generalized predictive control (CMGPC) strategy is designed and implemented in a simulation of 375 MW thermal power plants. This CMGPC algorithm does not resort to on-line parameter estimation and can more exactly predict the future outputs of the nonlinear plants, so it shows better reliability and control performance than the usual GPC algorithm.  相似文献   
179.
This paper presents the high-performance DRAM array and logic architecture for a sub-1.2-V embedded silicon-on-insulator (SOI) DRAM. The degradation of the transistor performance caused by boosted wordline voltage level is distinctly apparent in the low voltage range. In our proposed stressless SOI DRAM array, the applied electric field to the gate oxide of the memory-cell transistor can he relaxed. The crucial problem that the gate oxide of the embedded-DRAM process must be thicker than that of the logic process can be solved. As a result, the performance degradation of the logic transistor can be avoided without forming the gate oxides of the memory-cell array and the logic circuits individually. In addition, the data retention characteristics can be improved. Secondly, we propose the body-bias-controlled SOI-circuit architecture which enhances the performance of the logic circuit at sub-1.2-V power supply voltage, Experimental results verify that the proposed circuit architecture has the potential to reduce the gate-delay time up to 30% compared to the conventional one. This proposed architecture could provide high performance in the low-voltage embedded SOI DRAM  相似文献   
180.
The distributions of the number of molecules per cluster (cluster size) of ethanol cluster ion beams were measured by the time-of-flight method. The cluster sizes at the peak and minimum tail (minimum size) of the distribution increased with increase of the retarding voltage. A difference appeared between the measured minimum size and the calculated values using a formula based on the early measurements on the velocity distributions of gas clusters.  相似文献   
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