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131.
132.
Alexandre Antunes Ribeiro Rodrigo Fernando Costa Marques Antônio Carlos Guastaldi João Sinézio de Carvalho Campos 《Journal of Materials Science》2009,44(15):4056-4061
Many techniques have been used to coat metallic substrate with bioceramics. The aim of this study was to study the physical-chemical
characteristics of polyvinylidene fluoride (α-PVDF)/hydroxyapatite (HA) composite coating, obtained by casting method, on
commercially pure titanium (α-CP Ti) substrate surface modified by laser beam irradiation. The preparation of coating was
done for mixing α-PVDF pellets shape dissolved in dimethylacetamide (DMA) with HA/DMA emulsion. The mixture was poured onto
the α-CP Ti sample and left to dry in an oven. CP Ti plates were coated with α-PVDF/HA composite film, in proportions of 100/00
and 60/40 in weight, and characterized by particle size analysis, scanning electron microscopy, energy dispersive spectroscopy
(EDS), X-ray diffractometry, thickness measurement and contact angle. Uniform coating with a small thickness variation along
the coated surface was successfully obtained. 相似文献
133.
Temperature Stability of Lead‐Free Niobate Piezoceramics with Engineered Morphotropic Phase Boundary 下载免费PDF全文
Ruiping Wang Ke Wang Fangzhou Yao Jing‐Feng Li Florian H. Schader Kyle G. Webber Wook Jo Jürgen Rödel 《Journal of the American Ceramic Society》2015,98(7):2177-2182
The temperature dependence of piezoelectric properties (direct piezoelectric coefficient d33, converse piezoelectric coefficient d33(E = 0), strain S and electromechanical coupling coefficient kp) for two niobate‐based lead‐free piezoceramics have been contrasted. 0.92(Na0.5K0.5)NbO3–0.02(Bi1/2Li1/2)TiO3–0.06BaZrO3 (6BZ/2BLT/92NKN) has a morphotropic phase boundary (MPB) between rhombohedral and tetragonal at room temperature and 0.92(Na0.5K0.5)NbO3–0.03(Bi1/2Li1/2)TiO3–0.05BaZrO3 (5BZ/3BLT/92NKN) features an MPB engineered to be located below room temperature. At 30°C, d33, d33(E = 0), S (at 2 kV/mm), and kp are 252 pC/N, 230 pm/V, 0.069%, 0.51 for 5BZ/3BLT/92NKN; and 348 pC/N, 380 pm/V, 0.106%, 0.57 for 6BZ/2BLT/92NKN, respectively. With increasing temperature, the piezoelectric properties decrease. At 200°C, d33, d33(E = 0), S (at 2 kV/mm), and kp are 170 pC/N, 160 pm/V, 0.059%, 0.36 for 5BZ/3BLT/92NKN; and 181 pC/N, 190 pm/V, 0.061%, 0.39 for 6BZ/2BLT/92NKN. It is found that the electromechanical coupling coefficient has a better temperature stability than the piezoelectric coefficient in the studied system due to a large temperature‐dependent compliance change. The results demonstrate that engineering an MPB is highly effective in tailoring temperature stability of piezoceramics. 相似文献
134.
Professor Jorge Manuel Martins Margarida Lopes Almeida Professor Cristina Maria Coelho Dr João Ferra 《The Journal of Adhesion》2015,91(10-11):792-800
This paper presents a study on the curing conditions of several resin-impregnated papers and its impact on the performance of HPL (high-pressure decorative laminate). A new methodology for evaluating the bond strength development between the different layers of a HPL(overlay, decorative, and kraft papers) was developed using ABES (Automated Bonding Evaluation System) equipment. The proposed method can be applied to the study of the curing step of the different impregnated paper and the development of bonds between them (overlay paper on decorative paper, decorative paper on kraft paper, and kraft paper on kraft paper) trying to simulate the hot-pressing of an industrial HPL. This will permit to establish a more adapted temperature gradient in hot-press in order to achieve the same curing rate for all layers and provide a good final overall product quality. 相似文献
135.
2D Materials: Rotation‐Misfit‐Free Heteroepitaxial Stacking and Stitching Growth of Hexagonal Transition‐Metal Dichalcogenide Monolayers by Nucleation Kinetics Controls (Adv. Mater. 25/2015) 下载免费PDF全文
136.
Frank Vanheel Jo Verhaevert Eric Laermans Ingrid Moerman Piet Demeester 《Wireless Communications and Mobile Computing》2015,15(9):1342-1354
Receiver Strength Signal Indication based Wireless Sensor Networks offer a cheap solution for location‐aware applications. For a final breakthrough these systems need fast deployment and easy auto‐configuration. In this study, we use the real‐life iMinds test bed to expand a two‐dimensional localization algorithm to the pseudo third dimension with very low additional computational time. Our experiments show that this fast three‐dimensional algorithm has no outliers and avoids manual calibration. Our algorithm has lower position errors than a maximum likelihood algorithm with a mean square error cost function. Furthermore, with non‐parametric statistical tests, we show that our previously designed two‐dimensional preprocessing performs equally well in pseudo‐three dimensions: the preprocessing reduces the position error in a statistically significant way.Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
137.
João P. F. Mota Viviane G. P. Ribeiro Fernando L. F. da Silva Antônio E. C. Junior Davi R. Oliveira Lloyd R. V. Kotzebue 《分离科学与技术》2016,51(14):2473-2483
The present work made a comparative study between two purification methods, column chromatography and recrystallization, for compounds derived from cardanol, a by-product of the cashew industry (Anacardium occidentale L.). The compounds were successfully synthesized and characterized, focusing our attention to results obtained in terms of yield, purity, generation of solid waste and amount of solvent used in each purification process. For all the synthesized compounds, the amount of solvent used was greatly reduced in the recrystallization process, with purities above 80%, when compared to chromatographic column, which still demands high amounts of eluent. 相似文献
138.
Kamilla Soares de Mendonça João Renato de Jesus Junqueira Michel Cardoso de Angelis Pereira Marina Barbosa Vilela 《Drying Technology》2016,34(4):386-394
Osmotic dehydration assisted by ultrasound (ODAU) at low temperatures reduces water activity (aw) and maintains nutrients. The influence of solution concentration (SC; 20 to 60° Brix, xylitol and sorbitol) and ultrasound application time (tus, 0 to 40 min) in ODAU of yacon was studied with the aid of a response surface method. The optimum condition with respect to mass transfer parameters, aw, and fructan retention was SC of 60° Brix for both solutions and tus of 2.67 min for xylitol samples and 0 min for sorbitol samples. The application of ultrasound improved dehydration but resulted in depolymerization of fructans. 相似文献
139.
140.
Freestanding fiber mats of zeolitic imidazolate framework 7 via one‐step,scalable electrospinning 下载免费PDF全文
Seongpil An Ji Sun Lee Bhavana N. Joshi Hong Seok Jo Kirill Titov Jong‐San Chang Chul‐Ho Jun Salem S. Al‐Deyab Young Kyu Hwang Jin‐Chong Tan Sam S. Yoon 《应用聚合物科学杂志》2016,133(32)
We demonstrated the fabrication of freestanding zeolitic imidazolate framework 7 (ZIF‐7) nanofiber (NF) mats by means of one‐step, scalable electrospinning. The formation of ZIF‐7 nanoparticles embedded in polymer fibers was unambiguously pinpointed via X‐ray diffraction, transmission electron microscopy, and adsorption studies. The NF mats exhibited excellent characteristics, with an average diameter of 245 nm, in the adsorption and desorption of carbon dioxide (CO2); this makes them attractive candidates for gas separation and other selective filtration applications. This excellent property of the ZIF‐7 mats was explained by the gate‐opening phenomenon of ZIF‐7, which yielded a stepwise increase in the overall CO2 uptake capacity. The mechanical strength of the NF mats was also obtained via large‐strain uniaxial tensile deformation, which enabled preliminary assessment of the mat's suitability for textiles and membranes in targeting separation and filtration applications with large‐area permeability. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43788. 相似文献