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1.
Multimedia Tools and Applications - Visual object tracking is a key component in many computer vision applications. In real time visual tracking, abrupt changes in speed and direction of the object... 相似文献
2.
Dinabandhu Patra Ramakrishnan Ganesan Balaji Gopalan 《International Journal of Hydrogen Energy》2021,46(50):25486-25499
We report the catalytic enhancement of hydrogen generation by 1) in situ Fe (0) formed and 2) nitroarenes substrates during Fe3O4@Pd core-shell nanoparticles catalyzed tandem reaction. The active hydrogen species are generated in Pd shell, which either combine to form H2 gas or take part in relatively faster nitroarene reduction reaction. The rate of hydrogen generation from ammonia borane is dependent on the nitroarene substrate and is higher when 4-nitrophenol is used. This is due to the difference in ammonia borane adsorption on the surface of the catalyst. During recyclability, the H2 generation rate of 2 wt% Pd loaded samples is higher than other compositions. Such an enhancement has been attributed to the formation of Fe (0) via γ-FeOOH mediated by Pd species, presumably through Pd(OH)2. The electronic connection between Fe and Pd interface is thus shown to play an important role in the catalytic enhancement of the tandem reaction. 相似文献
3.
Mohanta Abinash Pradhan Arpan Mallick Monalisa Patra K. C. 《Water Resources Management》2021,35(13):4535-4559
Water Resources Management - Accurate prediction of shear stress distribution along the boundary in an open channel is the key to solving numerous critical engineering problems such as flood... 相似文献
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5.
Sequential mixing as effective method in the reduction of percolation threshold of multiwall carbon nanotube in poly(methyl methacrylate)/high‐density poly(ethylene)/MWCNT nanocomposites 下载免费PDF全文
This work demonstrates sequential heating protocol to be an effective method in the reduction of percolation threshold of multiwall carbon nanotube (MWCNT) in (70/30 w/w) poly(methyl methacrylate) (PMMA)/high‐density poly(ethylene) (HDPE)/MWCNT nanocomposites. Here, the percolation threshold (Pc) value was reduced to 0.08 wt % of MWCNT, which is the lowest among the ever reported values of Pc for the PMMA system. Moreover, a co‐continuous morphology of the minor HDPE phase was evident throughout the major PMMA phase in a highly asymmetric composition (70/30 w/w) of the blend constituents. The AC conductivity as well as the dielectric permittivity values were increased with increase in loading of MWCNT in the nanocomposites. The detailed analysis of electrical and morphological properties is discussed in depth in the article. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40235. 相似文献
6.
Banani Kundu Nicholas E. Kurland Subia Bano Chinmoy Patra Felix B. Engel Vamsi K. Yadavalli Subhas C. Kundu 《Progress in Polymer Science》2014
Biomaterials of either natural or synthetic origin are used to fabricate implantable devices, as carriers for bioactive molecules or as substrates to facilitate tissue regeneration. For the design of medical devices it is fundamental to use materials characterized by non-immunogenicity, biocompatibility, slow and/or controllable biodegradability, non-toxicity, and structural integrity. The success of biomaterial-derived biodevices tends to be based on the biomimetic architecture of the materials. Recently, proteins from natural precursors that are essentially structural and functional polymers, have gained popularity as biomaterials. The silks produced by silkworms or spiders are of particular interest as versatile protein polymers. These form the basis for diverse biomedical applications that exploit their unique biochemical nature, biocompatibility and high mechanical strength. This review discusses and summarizes the latest advances in the engineering of silk-based biomaterials, focusing specifically on the fabrication of diverse bio-mimetic structures such as films, hydrogels, scaffolds, nanofibers and nanoparticles; their functionalization and potential for biomedical applications. 相似文献
7.
In this article, a fast context-sensitive threshold selection technique is presented to solve the image segmentation problems. In lieu of histogram, the proposed technique employs recently defined energy curve of the image. First, the initial thresholds are selected in the middle of two consecutive peaks on the energy curve. Then based on the cluster validity measure, the optimal number of potential thresholds and the bounds where the optimal value of each potential threshold may exist are determined. Finally, genetic algorithm (GA) is employed to detect the optimal value of each potential threshold from their respective defined bounds. The proposed technique incorporates spatial contextual information of the image in threshold selection process without loosing the benefits of histogram-based techniques. Computationally it is very efficient. Moreover, it is able to determine the optimal number of segments in the input image. To assess the effectiveness of the proposed technique, the results obtained are compared with four state-of-the-art methods cited in the literature. Experimental results on large number of images confirmed the effectiveness of the proposed technique. 相似文献
8.
Dextrin crosslinked with poly(lactic acid): A novel hydrogel for controlled drug release application 下载免费PDF全文
A new class of biodegradable crosslinked hydrogel, consisting of hydrophobic polylactic acid (PLA) and hydrophilic dextrin in presence of crosslinker N,N‐methylene bisacrylamide (MBA) has been synthesized by free‐radical polymerization technique using potassium persulfate (KPS) as initiator. By variation of crosslinker concentration, a series of hydrogels have been prepared and the optimized grade has been selected on the basis of higher crosslinking efficiency as well as lower equilibrium swelling characteristics, XRD analysis. The hydrogels have been characterized by FTIR spectra, 13C‐NMR spectra, CHN analysis, SEM analysis, swelling characteristics, and toxicity study. In vitro release study of model drugs (ciprofloxacin and ornidazole) from hydrogel matrix has been performed in various buffer solutions at 37°C. The drug release kinetics and mechanism have been studied using zero order, first‐order kinetic models, Korsemeyar–Peppas model, Higuchi model, Hixson–Crowell model, and nonlinear Kopcha model. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40039. 相似文献
9.
Modak Pranabananda Patra Sudipta Mitra Rahul Chakrabarti Debalay 《Metallurgical and Materials Transactions A》2018,49(6):2219-2234
Metallurgical and Materials Transactions A - Effect of the initial as-cast structure on the microstructure–texture evolution during thermomechanical processing of 409L grade ferritic... 相似文献
10.
In this article, we introduce an eco‐friendly approach to achieve electrical conductivity at sufficiently lower loading of MWCNT in the PS/LDPE/MWCNT nanocomposites through judicious control of temperature during melt blending. The percolation threshold was achieved at 0.21 wt% of MWCNT following this method, which is lower, compared to the result obtained from direct mixing as well as the previously reported data. The morphological analysis revealed a co‐continuous structure of the (70/30, PS/LDPE)/MWCNT nanocomposites in such a high asymmetric composition of blend constituents, which facilitates in the lowering of percolation threshold through selective dispersion of MWCNT in the minor LDPE phase. The electron conduction in the nanocomposites has well been explained in terms of tunneling mechanism, supporting thin coating of polymer over individual CNTs. The morphological, electric and dielectric properties have been well explained in this article. POLYM. COMPOS., 36:1574–1583, 2015. © 2014 Society of Plastics Engineers 相似文献