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101.
Metallic nickel (Ni) was successfully dispersed onto a polyaniline (PANI) matrix by a simple one‐step electrochemical method. Ni particles as deposited onto the polymer seemed to be much smaller compared to those deposited onto bare Pt. The size of the Ni deposits was found to be influenced by the electrolytic bath composition and potential sweep rate. The PANI matrix thus dispersed with Ni particles exhibited ferromagnetic behavior and a lower electrical conductance. The decrease in conductivity may be attributed to the partial blockage of the conductive path by the Ni particles thus embedded in the polymer matrix. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 321–327, 2006 相似文献
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Shelton B.S. Lambert D.J.H. Jian Jang Huang Wong M.M. Chowdhury U. Ting Gang Zhu Kwon H.K. Liliental-Weber Z. Benarama M. Feng M. Dupuis R.D. 《Electron Devices, IEEE Transactions on》2001,48(3):490-494
The selective area growth (SAG) and properties of AlGaN/GaN heterojunction bipolar transistors (HBTs) grown by low-pressure metalorganic chemical vapor deposition (MOCVD) are described and analyzed. Transistors based on group III-nitride material are attractive for high-power and high-temperature applications. Much work has been focused on improving p-type material, as well as heterojunction interfaces. However, there have been very few reports on HBTs operating at room temperature, At this time, current gains for nitride-based HBTs have been limited to ~10. Selective area regrowth was applied to the growth of AlGaN/GaN HBTs to analyze its potential advantages as compared to more traditional growth techniques in order to realize improved electrical performance of the devices 相似文献
105.
Yun Ma Yun‐Ling Jia Yan‐Li Shang Fu‐Hui Liao Jun‐Ran Li Shao‐Hua Zhang Olivia Zhang 《应用聚合物科学杂志》2007,105(4):2427-2432
Novel electrorheological materials based on crosslinked chitosan doped with Y2(CO3)3 were synthesized with biocompatible chitosan as the substrate of the materials. The electrorheological performance, surface energy, and thermal decomposition behavior of the materials were investigated as functions of the composition change. The results show that doping Y2(CO3)3 can improve effectively the electrorheological performance of crosslinked chitosan with the formation of a metal–polymer complex when the doping degree is suitable. The surface energy plays an important role in influencing the electrorheological properties of the material. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献
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Chien H.-C. Hsueh Y.-T. Chowdhury A. Yu J. Chang G.-K. 《Photonics Technology Letters, IEEE》2010,22(3):182-184
109.
Mining sequential patterns is an important research issue in data mining and knowledge discovery with broad applications. However, the existing sequential pattern mining approaches consider only binary frequency values of items in sequences and equal importance/significance values of distinct items. Therefore, they are not applicable to actually represent many real‐world scenarios. In this paper, we propose a novel framework for mining high‐utility sequential patterns for more real‐life applicable information extraction from sequence databases with non‐binary frequency values of items in sequences and different importance/significance values for distinct items. Moreover, for mining high‐utility sequential patterns, we propose two new algorithms: UtilityLevel is a high‐utility sequential pattern mining with a level‐wise candidate generation approach, and UtilitySpan is a high‐utility sequential pattern mining with a pattern growth approach. Extensive performance analyses show that our algorithms are very efficient and scalable for mining high‐utility sequential patterns. 相似文献
110.
A novel graft copolymer of [2-(methacryloyloxy)ethyl] trimethylammonium chloride onto poly(vinyl alcohol) has been synthesized
and it is cross-linked by glutaraldehyde for the investigation of its efficiency in removing Cr(VI) from aqueous solution.
The chemical nature of the ion-exchange resin has been elucidated with the help of chemical test, Fourier transform infrared,
thermo gravimetric analysis and DTA. Particle size, surface area, ion-exchange capacity, optimum pH, reaction time and temperature
for Cr(VI) extraction were determined. Chromium(VI) adsorption kinetics, isotherm and thermodynamics have been studied. A
plausible mechanism for chromium ion-exchange has been suggested. 相似文献