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排序方式: 共有1459条查询结果,搜索用时 15 毫秒
61.
E. Subramanian G. Anitha M. Karthik Selvam M. Ibrahim Ali Badusha 《Bulletin of Materials Science》2005,28(1):55-61
An investigation on the effect ofβ-cyclodextrin (CD) in both free and inclusion-complexed forms with a guest anionic metal complex, dioxalatodiaquochromate(III)
(DDC), on the characteristics of conducting polyaniline (PANI) is carried out. Four materials, PANI (i.e. PANI-SO
4
2−
), PANI-DDC, PANI-CD and PANI-CD + DDC were prepared byin situ
chemical oxidative polymerization in aqueous H
2SO4 at pH 1 and subjected to electrical conductivity and spectral (IR and UV-vis bd measurements. DDC and CD when separately incorporated, reduce the conductivity of PANI by about half whilst their inclusion
complex CD + DDC enhances it. Spectral characterization reveals that DDC as a dopant and CD as an encapsule exhibit their
effects through adverse interaction with imine-amine N centres and benzenoid moiety of PANI. The inclusion complex CD + DDC,
on the contrary, functions as a dopant by lying in between the chains and seems to promote the extended conformation of PANI
chain and hence theπ
-electron delocalization. Exposure of the material to methanol vapour causes a decrease in conductivity in PANI and PANI-CD while an increase in PANI-CD
+ DDC. This study makes explicit the distinct role of CD as an encapsule and CD + DDC inclusion complex as a dopant in altering
the electrical property of PANI. 相似文献
62.
Adour V. Kabakian Vijaya Shankar William F. Hall 《Journal of scientific computing》2004,20(3):405-431
A parallel, unstructured, high-order discontinuous Galerkin method is developed for the time-dependent Maxwell's equations, using simple monomial polynomials for spatial discretization and a fourth-order Runge–Kutta scheme for time marching. Scattering results for a number of validation cases are computed employing polynomials of up to third order. Accurate solutions are obtained on coarse meshes and grid convergence is achieved, demonstrating the capabilities of the scheme for time-domain electromagnetic wave scattering simulations. 相似文献
63.
64.
Kodgirwar Vidya P. Deosarkar Shankar B. Joshi Kalyani R. 《Wireless Personal Communications》2020,110(1):423-444
Wireless Personal Communications - Applications of wireless sensor networks (WSNs) are increasing tremendously to facilitate and establish a link between the physical world and information system.... 相似文献
65.
Optimization and Engineering - Aircraft ejection systems are lifesaving devices used, in case of emergencies for military pilots. As per current literature the success rate of ejections happening... 相似文献
66.
67.
B. Karthik G. Sai Gautam N. R. Karthikeyan B. S. Murty 《Metallurgical and Materials Transactions A》2012,43(4):1323-1327
A model was developed to estimate the energy transfer from milling media to the powder during milling carried out in Simoloyer
CM 01 (Zoz GmbH, Wenden, Germany), a horizontal attritor high-energy ball mill. The model was then used to estimate the energy
transfer in milling of iron at 1000 rpm. Furthermore, the time required to achieve a particular grain size was formulated
as a function of milling speed, using the model developed for the energy transfer. The results were verified at 500 rpm and
1500 rpm for iron and aluminum. 相似文献
68.
69.
70.
The design of Cellular Manufacturing Systems (CMS) has attained the significant attention of academicians and practitioners over the last three decades. Minimizing intercellular movements while maximizing utilization of machines are the main objectives of interest in designing CMS and are considered in present research. In this paper, the drawbacks of former neural networks-based approaches to cell formation are discussed. The standard version of cell formation problem is formulated and a 'Transiently Chaotic Neural Network' (TCNN) with supplementary procedures is introduced as a powerful rival. A simplified network is constructed. After developing the related equations the approach is tested using the proposed algorithm with 18 problems selected from literature. The results are compared with various other approaches including ART1, Extended-ART1, Ortho-Synapse Hopfield Neural Network (OSHN), etc. The main advantages of our proposed method are: (1) the ability to avoid the local optima trap, (2) the ability to solve problems of different sizes with the same set of values for parameters, and (3) the less computation time. The results also indicate considerable improvement in grouping efficiency through the proposed approach. 相似文献