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81.
82.
Wireless Personal Communications - In this paper a combination of rectangular and elliptical fractal geometry is applied on a regular hexagonal wide slot antenna fabricated using a FR4 substrate to...  相似文献   
83.
Das  Dibakar  Das  Debabrata 《Wireless Networks》2019,25(1):255-267
Wireless Networks - Though, Software Defined Networking (SDN) started with the wired networks, several architectural solutions have been proposed to incorporate SDN in the wireless domain, to...  相似文献   
84.
Das  N. Chatterjee  J.S. 《Electronics letters》1981,17(13):441-442
Experiment conducted on a microstrip quarterwave antenna structure on a typical ferrite substrate reveals reduction in size, interesting radiation characteristics and a broadband nature over a wide range of frequencies in the lower UHF region.  相似文献   
85.
Cadmium (Cd), a highly toxic environmental pollutant, induces hepatic disorders. The present study has been undertaken to investigate the protective role of the fruit extract of Terminalia arjuna (AE) against Cd-induced oxidative liver impairment using a murine model. Cadmium reduced hepatocytes viability, activated MAPKs, disturbed Bcl-2 family protein balance, increased reactive oxygen species (ROS) production and induced apoptotic cell death by mitochondria dependent caspases-3 activation. AE treatment, however, suppressed all the apoptotic actions of cadmium. Similarly, mice treated with cadmium altered a number biomarkers related to hepatic oxidative stress and other apoptotic indices. Oral administration of AE both pre and post prevented all the Cd-induced hepatic damages.  相似文献   
86.
Anup Das  Sourabh Ghosh 《Polymer》2011,52(17):3800-3810
Stimulus responsive hydrogels are being considered as one of the most crucial biomaterials of current generation. A new technique has been established for developing hydrogels based on Acrylic acid (AAc) and N-[3-(Dimethylamino)propyl]-methacrylamide (DMAPMA), and relevant mechanism has been delineated. Aqueous redox copolymerization of different molar ratios of AAc and DMAPMA at 41 ± 1 °C, leading to the formation of interlocked nanogels of ∼300 nm diameter, which acted as the building blocks of a series of superabsorbent hydrogels having robust, honey-comb type three-dimensional architecture. Monomer composition, monomer feed ratio and water content in feed has been found to be important factors in the development of the stable poly(AAc-co-DMAPMA) hydrogel membranes (PADMAs) without any active crosslinking agent. At the cues of pH change from 7.0 to 3.5, pulsatile swelling-deswelling behavior varied, ranging from ∼5900% to ∼60% (mass) respectively, underlining smart hydrogel characteristics needed for specific biomedical applications. Elastic modulus of the gels, equilibrated at pH 7.0, is recorded to be >15 kPa under uniaxial compression. Underlying mechanism of the formation of such robust three-dimensional structures in poly(AAc-co-DMAPMA) hydrogel membranes, and the origin of hierarchical ‘nano-to-macro’ scale morphological features has been proposed.  相似文献   
87.
Das  Gourab  Bose  Sukanta  Mukhopadhyay  Sumita  Banerjee  Chandan  Barua  Asok K. 《SILICON》2019,11(1):487-493
Silicon - Due to in-situ deposition process doped SiOx material attracts the PV community as intermediate reflecting layer (IRL) for the less hazardous deposition process. Previously we have been...  相似文献   
88.
Fabrication of self-assembled nanostructures is one of the important aspects in nanoscience and nanotechnology. The study of self-assembled soft materials remains an area of interest due to their potential applications in biomedicine. The versatile properties of soft materials can be tuned using a bottom up approach of small molecules. Peptide based self-assembly has significant impact in biology because of its unique features such as biocompatibility, straight peptide chain and the presence of different side chain functionality. These unique features explore peptides in various self-assembly process. In this review, we briefly introduce chemical reaction-mediated peptide self-assembly. Herein, we have emphasised enzymes, native chemical ligation and photochemical reactions in the exploration of peptide self-assembly.  相似文献   
89.
Multiwalled carbon nanotube (MWCNT)/alumina (Al2O3) nanocomposites containing CNT from 0.15 vol.% to 2.4 vol.% have been successfully fabricated by simple wet mixing of as-received commercial precursors followed by pressureless sintering. Extent of densification of nanocomposites sintered at low temperature (e.g. 1500 °C) was <90%, but increased up to ∼99% when sintered at 1700 °C and offered superior performance compared to pure Al2O3. Nanocomposites containing 0.3 vol.% MWCNT and sintered at 1700 °C for 2 h in Argon led to ∼23% and ∼34% improvement in hardness and fracture toughness, respectively, than monolithic Al2O3. In addition, the highest improvement (∼20%) in bending strength was obtained for 0.15 vol.% MWCNT/Al2O3 nanocomposite compared to pure Al2O3. Weibull analysis indicated reliability of nanocomposites increased up to 0.3 vol.% MWCNT, whereas, beyond that loading consistency was the same as obtained for pure Al2O3. Detailed microstructure and fractographic analysis were performed to assess structure-property relationship of present nanocomposites.  相似文献   
90.
Singh V  Singh S  Das S  Kumar A  Self WT  Seal S 《Nanoscale》2012,4(8):2597-2605
In the present article a facile synthesis of cerium oxide nanoparticles (CNPs) encapsulated in PLGA microparticles is reported. The release kinetics of the CNPs from the PLGA matrix was investigated under acidic, basic and near-neutral pH. A diffusion model was applied to determine the diffusivity of the CNPs from the PLGA matrix. The morphology of the degraded PLGA particles was characterized by high resolution SEM. Superoxide dismutase (SOD) mimetic activity was retained in released CNPs for a longer period of time (~90 days) under different pH. PLGA encapsulated CNP showed excellent biocompatibility. This study demonstrates a potential strategy to deliver CNPs using biodegradable PLGA that ensures a slow release of the CNPs over a long period of time. Thus, the synthesized PLGA encapsulated CNPs could find potential applications in tissue engineering like bone remodelling and regeneration, and protection from disorders caused by neurodegeneration.  相似文献   
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