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81.
82.
Bharat Kumar Reddy Sanapalli Shivaramakrishnan Balasubramanian Jawahar Natarajan Uday Krishna Baruah 《Drug development and industrial pharmacy》2018,44(10):1650-1658
5-Aminosalicylic acid (5-ASA) is an aminosalicylate anti-inflammatory drug, which is also known as mesalazine or mesalamine. Currently employed in treating inflammatory bowel disease, ulcerative colitis, inflamed anus or rectum, and maintain remission in Crohn's disease. Evidence from the researchers highlighted its significant re-epithelization in allergic asthma, aphthous, and gastric ulcerative conditions. The objective of the study was to formulate the pluronic lecithin organogel (PLO) containing 5-ASA and evaluate its wound-healing ability in a full thickness excision wound rat model. The data obtained from in silico docking studies revealed 5-ASA is having an affinity towards the transforming growth factor-beta (TGF-β) specifically towards beta1. Among various formulations prepared (F1 to F8), F1, and F6 have shown a maximum in vitro drug release with optimum pH and viscosity. From MTT assay it was found that selected PLO formulations showed no toxicity and enhanced cell proliferation in HaCaT cell lines. In vivo wound-healing studies in albino Wistar rats has revealed that PLO accelerates wound closure and reepithelization to the statistically significant level on day 3 (p?.05) in comparison with untreated wounds. In conclusion, the overall results suggest that 5-ASA PLO gel is a potential therapeutic option for the treatments of wounds, however, further studies are highly warrened to determine the various mechanisms of 5-ASA in regulating the cell migration and reepithelization in wound healing to outspread its use in clinics. 相似文献
83.
Da-Ren Hang Sk Emdadul Islam Krishna Hari Sharma Shiao-Wei Kuo Cheng-Zu Zhang Jun-Jie Wang 《Nanoscale research letters》2014,9(1):632
Vertically aligned ZnO nanorods (NRs) on aluminum-doped zinc oxide (AZO) substrates were fabricated by a single-step aqueous solution method at low temperature. In order to optimize optical quality, the effects of annealing on optical and structural properties were investigated by scanning electron microscopy, X-ray diffraction, photoluminescence (PL), and Raman spectroscopy. We found that the annealing temperature strongly affects both the near-band-edge (NBE) and visible (defect-related) emissions. The best characteristics have been obtained by employing annealing at 400°C in air for 2 h, bringing about a sharp and intense NBE emission. The defect-related recombinations were also suppressed effectively. However, the enhancement decreases with higher annealing temperature and prolonged annealing. PL study indicates that the NBE emission is dominated by radiative recombination associated with hydrogen donors. Thus, the enhancement of NBE is due to the activation of radiative recombinations associated with hydrogen donors. On the other hand, the reduction of visible emission is mainly attributed to the annihilation of OH groups. Our results provide insight to comprehend annealing effects and an effective way to improve optical properties of low-temperature-grown ZnO NRs for future facile device applications. 相似文献
84.
85.
Babak Ghorbani Krishna Vijayaraghavan 《International Journal of Hydrogen Energy》2018,43(20):9733-9748
In the current study, a single cell of a planar SOFC is firstly modeled in 3D using commercial SOFC module of ANSYS Fluent and the results are validated against the experimental investigations in the literature. Many researchers have used ANSYS Fluent for simulating solid oxide fuel cells. However, there is a huge gap in the literature on explaining the detailed procedure that should be followed in order to use this software effectively. A thorough step-by-step approach is presented to provide a deep insight into the software. Thereafter, a simplified quasi-2D method with infinitely shorter computational time is developed and the results are compared with the 3D model. It is found that the reduced model is capable of being utilized as an alternate method for both online diagnosis and designing active control strategies. 相似文献
86.
87.
Rama Krishna Dasari V. M. Pandharipande 《Radioelectronics and Communications Systems》2016,59(10):442-448
In this paper we suggest a reconfigurable wheel antenna based on PIN diodes. The antenna is excited by a single-feed and operates in S-band and X-band. Proposed antenna’s structure is composed of two circular rings that are excited by multiple PIN diodes and microstrip lines. Antenna’s reconfiguration is realized by inserting switches into spokes and peripheral regions of a wheel antenna. The required resonance frequency is provided by combination of the structures which are controlling by PIN diodes. Developed antenna was fabricated on a RT duroid material and its pattern measurements were carried out in the outdoor environment. The measured results have demonstrated antenna’s ability to be reconfigurated and good radiation pattern characteristics within two frequency bands. 相似文献
88.
Krishna P. Yagati Ravi N. Bathe Koteswararao V. Rajulapati K. Bhanu Sankara Rao G. Padmanabham 《Journal of Materials Processing Technology》2014,214(12):2949-2959
In this work, joining of aluminium alloy AA6061-T6 to Interstitial Free steel using pulsed gas metal arc welding process has been attempted. The effect of different surface conditions of steel (viz, galvanized, galvanealed and uncoated) and gap between the sheets on braze joint formation have been investigated. Galvanized steel surface showed good bead width, joint formation and lap shear strength compared to the other two combinations. Interface gap has not affected the wetting behaviour significantly but presence of a gap of 300 μm or so helped in escape of zinc vapour during the process there by avoiding formation of any crevice or macroporosity in the joint. Features and properties of the joint are characterized by metallography, fractography, energy dispersive spectroscopy (EDS) and lap shear tests. Load carrying capacity of Al-Galvanized steel was highest (222 N/mm of seam length) compared to other combinations, aided by better wetting due to presence of Zn on the surface and minimum porosity due to interfacial gap provided during brazing. 相似文献
89.
90.
Optimization of Lithium Content and Sintering Aid for Maximized Li+ Conductivity and Density in Ta‐Doped Li7La3Zr2O12
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Narayanasamy Janani Sampathkumar Ramakumar Subramanian Kannan Ramaswamy Murugan 《Journal of the American Ceramic Society》2015,98(7):2039-2046
Ta‐doped cubic phase Li7La3Zr2O12 (LLZ) lithium garnet received considerable attention in recent times as prospective electrolyte for all‐solid‐state lithium battery. Although the conductivity has been improved by stabilizing the cubic phase with the Ta5+ doping for Zr4+ in LLZ, the density of the pellet was found to be relatively poor with large amount of pores. In addition to the high Li+ conductivity, density is also an essential parameter for the successful application of LLZ as solid electrolyte membrane in all‐solid‐state lithium battery. Systematic investigations carried out through this work indicated that the optimal Li concentration of 6.4 (i.e., Li6.4La3Zr1.4Ta0.6O12) is required to obtain phase pure, relatively dense and high Li+ conductive cubic phase in Li7?xLa3Zr2?xTaxO12 solid solutions. Effort has been also made in this work to enhance the density and Li+ conductivity of Li6.4La3Zr1.4Ta0.6O12 further through the Li4SiO4 addition. A maximized room‐temperature (33°C) total (bulk + grain boundary) Li+ conductivity of 3.7 × 10?4 S/cm and maximized relative density of 94% was observed for Li6.4La3Zr1.4Ta0.6O12 added with 1 wt% of Li4SiO4. 相似文献