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1.
Wireless Personal Communications - Massive Multiple-Input Multiple-Output (MIMO) technology has the potential to deliver high spectral efficiencies by leveraging the ability to form narrow beams... 相似文献
2.
Vaidhegi Kugarajah Moogambigai Sugumar Elamathi Swaminathan Nagaraj Balasubramani Sangeetha Dharmalingam 《International Journal of Hydrogen Energy》2021,46(42):22134-22148
Hydrothermally prepared zinc oxide nanorods are sulphonated (S–ZnO NR) and incorporated into 15% Sulphonated Poly (1,4-Phenylene Ether Ether Sulfone) (SPEES) to improve the hydrophilicity, water uptake and ion transfer capacity. Water uptake and ion transfer capacity increased to 34.6 ± 0.6% and 2.0 ± 0.05 meq g?1 from 29.8 ± 0.3% and 1.4 ± 0.04 meq g?1 by adding 7.5 wt% S–ZnO NR to SPEES. Morphological studies show the prepared S–ZnO NR is well dispersed in the polymer matrix. SPEES +7.5 wt% S–ZnO NR membrane exhibits optimum performance after three-weeks of continual operation in a fabricated microbial fuel cell (MFC) to produce a maximum power density of 142 ± 1.2 mW m?2 with a reduced biofilm compared to plain SPEES (59 ± 0.8 mW m?2), unsulphonated filler incorporated SPEES (SPEES + 7.5 wt% ZnO, 68 ± 1.1 mW m?2) and Nafion (130 ± 1.5 mW m?2) thereby suggesting its suitability as a sustainable and improved cation exchange membrane (CEM) for MFCs. 相似文献
3.
P. Sampath Brijesh Kakarla Raghava Reddy C. Venkata Reddy Nagaraj P. Shetti Raghavendra V. Kulkarni Anjanapura V. Raghu 《化学工程与技术》2020,43(7):1240-1248
Hydrogen fuel is a promising alternative to fossil fuels because of its energy content, clean nature, and fuel efficiency. However, it is not readily available. Most current producion processes are very energy intensive and emit carbon dioxide. Therefore, this article reviews technological options for hydrogen production that are eco-friendly and generate clean hydrogen fuel. Biological methods, such different fermentation processes and photolysis are discussed together with the required substrates and the process efficiency. 相似文献
4.
Spectroscopic information of gadolinium isotopes is necessary to exploit the full potential of various isotopes in nuclear and medical applications. Container materials to handle liquid gadolinium during spectroscopic studies is an important aspect. Tantalum carbide (TaC) has excellent stability and also exhibits superior resistance to attack by various reactive actinide metals at high temperature for long durations. Tantalum crucibles with TaC coating were prepared and tested for compatibility against liquid gadolinium at 1673?K upto 14?h in vacuum. Optical microscopy and SEM/EDS investigations were done to evaluate the micro structural features of the coating and the liquid gadolinium attack. Experimental results show that TaC coating exhibits excellent corrosion resistance against liquid gadolinium at 1673?K. 相似文献
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Wireless Personal Communications - The rapid development of Information and Communication Technology and the growing number of devices connected to the Internet make the Internet of Things (IoT) as... 相似文献
7.
S. P. Divya M. Nagaraj M. Kesavamoorthy S. A. Srinivasan B. Ravisankar 《Transactions of the Indian Institute of Metals》2018,71(1):67-77
ECAP is an effective process to improve the mechanical strength and wear resistance along with mechanical and microstructural properties. AA2014 solutionized at 495 °C and aged at 195 °C was subjected to Equal Channel Angular Pressed (ECAP) through route A and Bc at room temperature. It was well proved that the mechanical strength increased due to ECAP in AA2014. In order to investigate their wear behavior after ECAP, dry sliding wear tests were conducted using vacuum tribometer at nominal loads of 10N and 30N with constant speed of 2 m/s for sliding distance of 2000 m. The co-efficient of friction and loss in volume were decreased after ECAP both in route A and Bc. The dominant wear mechanisms observed were adhesive, delamination and stick slip process. In addition to these wear mechanisms, abrasive wear also appeared along with transfer of iron particles from the counter surface to the AA2014 pin. Presence of black powder and oxide formation were observed using EDAX analysis on wear debris. Routes A and Bc showed similar wear mechanisms and characteristics which were better than in unECAPed specimens. 相似文献
8.
Muthupandi Nagaraj Devanathan Perumal Muthusamy Boominathan Nattamai Bhuvanesh 《Journal of Sulfur Chemistry》2014,35(1):24-30
The attempted selenium dioxide oxidation of substituted diphenacyl sulfides in anticipation of further functionalization led to a series of α -ketoacids 3 via oxidation followed by C?S bond cleavage. Two minor products, 5 and 6, have also been isolated and a mechanistic pathway for the formation of 3, 5 and 6 has been proposed. 相似文献
9.
Prasanna Thiyagasundaram Junqiang Wang Bhavani V. Sankar Nagaraj K. Arakere 《Engineering Fracture Mechanics》2011,(6):1277-1288
Fracture toughness of open-cell foams consisting of tetrakaidecahedral unit cells is predicted by simulating crack propagation using a finite element (FE) based micromechanical model. The inputs to the model are the geometric parameters required to model the repeating unit cell and tensile strength of the foam ligament or strut. Cracks are created by removing certain number of cells pertaining to a crack length. The FE model consists of a local micro-scale region surrounding the crack tip. For an assumed stress intensity factor, the displacements along the boundary of the local model are calculated based on linear elastic fracture mechanics for orthotropic materials. The stresses in the ligaments ahead of the crack tip calculated from this micro-model in conjunction with the tensile strength of the strut material are used to predict fracture toughness. A parametric study with different micro-model sizes and different crack lengths is performed to check for convergence of predicted Mode-I, Mode-II and mixed mode fracture toughness values. The effect of applying rotations as additional boundary conditions along with translational displacement boundary conditions on the predicted fracture toughness values is also studied. 相似文献
10.
Mammalian defensins, a class of antibacterial peptides, are composed of 29-35 amino acids with six cysteines which form three disulfide bonds. Structural studies indicate a triple stranded beta-sheet structure with a well defined beta-hairpin loop at the C-terminal region. It is demonstrated in this report that 18 and 26 residue synthetic peptides corresponding to the beta-hairpin region, constrained by a single disulfide bond, have potent antimicrobial activity without hemolytic activity. Circular dichroism spectroscopy indicates that the single S-S bridge appears to constrain the peptides to a beta-structure. Peptides corresponding to the beta-hairpin region of defensins could thus be attractive candidates as therapeutic agents as well as good model compounds for investigation of the various physiological actions of defensins. 相似文献