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11.
Su Pei Lim Alagarsamy Pandikumar Nay Ming Huang Hong Ngee Lim 《International Journal of Hydrogen Energy》2014
Silver deposited titania (Ag/TiO2) nanocomposite thin films were fabricated by the simple sonochemical deposition of Ag on preformed aerosol-assisted chemical vapor deposited TiO2 thin films. The photelectrocatalytic performance of a newly fabricated Ag/TiO2-modified photoelectrode was studied for methanol oxidation under simulated solar AM 1.5G irradiation (100 mW/cm2). The Ag/TiO2-modified photoelectrode showed a photocurrent density of 1 mA/cm2, which is four times that of an unmodified TiO2 photoelectrode. The modification of Ag on the TiO2 surface significantly enhanced the photoelectrocatalytic performance by improving the interfacial charge transfer processes, which minimized the charge recombination. Density functional theory (DFT) calculation studies revealed that methanol could be easily adsorbed onto the Ag surfaces of Ag/TiO2 via a partial electron transfer from Ag to methanol. The newly fabricated Ag/TiO2-modified photoelectrode could be a promising candidate for photoelectrochemical applications. 相似文献
12.
Alagarsamy KRISHNAVEL Dusmata Kumar MOHANTA M. Jaya Bharata REDDY 《Frontiers in Energy》2013,7(3):288
With the prevailing power scenario, every watt-second of electrical energy has its own merit in satisfying the consumer demand. At the state of such a stringent energy demanding era, failure of a power generation equipment compounds the energy constraints which will not only result in a huge loss of generation but also have an impact on capital revenue. The unexpected failure of generator step-up (GSU) transformer is especially a major disturbance in the power system operation and leads to unscheduled outages with power delivery problems. The time lag in bringing back the equipment in service after rectification or replacement may increase the criticality as the process involves mobilization of spares and maintenance professionals. Hot atmosphere existing in the vicinity of thermal power stations running round-the-clock with more than 100% plant load factor (PLF) increases the thermal stress of the electrical insulation which leads to premature failure of windings, bushings, core laminations, etc. The healthy state of the GSU transformer has to be ensured to minimize the loss of power generation. As the predication related to failure of a GSU transformer is associated with some uncertainties, a fuzzy approach is employed in this paper along with actual field data and case studies for the well-being analysis of GSU transformer. 相似文献
13.
Sabeena Farvin K. Habeebullah Surendraraj Alagarsamy Zainab Sattari Sakinah Al-Haddad Saja Fakhraldeen Aws Al-Ghunaim Faiza Al-Yamani 《Journal of the American Oil Chemists' Society》2021,98(2):185-200
In the present study, the effect of enzymatic hydrolysis on the antioxidant activity of three red seaweeds (Chondria cornuta, Chondria dasyphylla, and Murrayella periclados) and two green seaweeds (Cladophora sp. and Ulva lactuca) from the Kuwait coast were evaluated. The seaweeds were hydrolyzed with five carbohydrases and three proteases, and the resulting extracts were tested for antioxidant activity. The total phenolic content and yield of the extracts varied greatly depending upon the species and enzyme used for hydrolysis. Of the 40 enzymatic extracts screened for antioxidant activity, the Viscozyme and Alcalase extracts of M. periclados, Neutrase and Ultraflo extracts of Cladophora sp., and Neutrase extracts of C. cornuta had high antioxidant activity compared to other enzymatic extracts in various in vitro assays. Fractionation of the extracts revealed that the radical scavenging and reducing power of the extracts were mainly due to phenolic fractions. In contrast, the iron-chelating ability was mainly due to protein fractions. The level of prevention of lipid oxidation in the liposome model system varied for different fractions of extracts and did not correlate with total phenolic content and other antioxidant properties. The results of the study show that, by hydrolyzing seaweeds with specific enzymes, customized seaweed extracts with specific bioactivity could be obtained. 相似文献
14.
Alireza Rafieerad Weiang Yan Keshav Narayan Alagarsamy Abhay Srivastava Niketa Sareen Rakesh C. Arora Sanjiv Dhingra 《Advanced functional materials》2021,31(46):2106786
MXene nanomaterials have sparked significant interest among interdisciplinary researchers to tackle today's medical challenges. In particular, colloidal MXene quantum dots (MQDs) offer the high specific surface area and compositional flexibility of MXene while providing improvements to aqueous stability and material–cell interactions. The current study for the first time reports the development and application of immunoengineered tantalum-carbide (Ta4C3Tx) MQDs for in vivo treatment of transplant vasculopathy. This report comes at a critical juncture in the field as poor long-term safety of other MXene compositions challenge the eventual clinical translatability of these materials. Using rational design and synthesis strategies, the Ta4C3Tx MQDs leverage the intrinsic anti-inflammatory and antiapoptotic properties of tantalum to provide a novel nanoplatform for biomedical engineering. In particular, these MQDs are synthesized with high efficiency and purity using a facile hydrofluoric acid-free protocol and are enriched with different bioactive functional groups and stable surface TaO2 and Ta2O5. Furthermore, MQDs are spontaneously uptaken into antigen-presenting endothelial cells and alter surface receptor expression to reduce their activation of allogeneic T-lymphocytes. Finally, when applied in vivo, Ta4C3Tx MQDs ameliorate the cellular and structural changes of early allograft vasculopathy. These findings highlight the robust potential of tailored Ta4C3Tx MQDs for future applications in medicine. 相似文献
15.
Thatikonda Santhosh Kumar Pallabi Gogoi Alagarsamy Perumal Pramod Sharma Dobbidi Pamu 《Journal of the American Ceramic Society》2014,97(4):1054-1059
We report a systematic investigation on crystal structure, microstructure, and microwave dielectric properties of (Mg1?xCox)TiO3 (x = 0–0.07) ceramics prepared by semialkoxide precursor method. All the as‐made samples exhibit an ilmenite structure with an incredible reduction in sintering temperature from 1350°C to 1200°C. Lattice parameter increases with increasing Co content due to the larger ionic radius of Co2+ as compared to Mg2+. The relative density, dielectric constant, and Q × f0 values increase with increasing Co up to 0.05 and decreases for x > 0.05. This is attributed to local lattice distortion, maximum relative density, and uniform grain growth. Q × f0 values were enhanced from 126 THz for x = 0 to a maximum value 170 THz for x = 0.05. A best combination of microwave dielectric properties (εr ~ 17.03, Q × f0 ~ 170 THz @ 9.4 GHz and τf of ?40 ppm/°C) was obtained for (Mg0.95Co0.05)TiO3 ceramic sintered at 1200°C for 3 h. The observed results reveal (Mg0.95Co0.05)TiO3 ceramic as one of the promising dielectric materials for low‐loss and millimeter‐microwave applications. 相似文献
16.
K. Alagarsamy 《Information Processing Letters》2005,96(1):36-40
Peterson's algorithm [G.L. Peterson, Myths about the mutual exclusion problem, Inform. Process. Lett. 12 (3) (1981) 115-116] for mutual exclusion has been widely studied for its elegance and simplicity. In Peterson's algorithm, each process has to cross n−1 stages to access the shared resource irrespective of the contention for the shared resource at that time, and allows unbounded bypasses. In [K. Block, T.-K. Woo, A more efficient generalization of Peterson's mutual exclusion algorithm, Inform. Process. Lett. 35 (1990) 219-222], Block and Woo proposed a modified algorithm that transforms the number stages to be crossed from fixed n−1 to t, where 1?t?n, and bounds the number of possible bypasses by n(n−1)/2. This paper proposes a simple modification that reduces the bound on the number of possible bypasses to optimal n−1. 相似文献
17.
Wireless Personal Communications - A multimodal biometric system uses more than one biometric methods of an individual to mitigate some of the drawbacks of a unimodal biometric system and improve... 相似文献
18.
A fully automated hybrid methodology using Cuckoo‐based fuzzy clustering technique for magnetic resonance brain image segmentation 下载免费PDF全文
Saravanan Alagarsamy Kartheeban Kamatchi Vishnuvarthanan Govindaraj Arunprasath Thiyagarajan 《International journal of imaging systems and technology》2017,27(4):317-332
This article aims at developing an automated hybrid algorithm using Cuckoo Based Search (CBS) and interval type‐2 fuzzy based clustering, so as to exhibit efficient magnetic resonance (MR) brain image segmentation. An automatic MR brain image segmentation facilitates and enables a radiologist to have a brief review and easy analysis of complicated tumor regions of imprecise gray level regions with minimal user interface. The tumor region having severe intensity variations and suffering from poor boundaries are to be detected by the proposed hybrid technique that could ease the process of clinical diagnosis and this tends to be the core subject of this article. The ability of the proposed technique is compared using standard comparison parameters such as mean squared error, peak signal to noise ratio, computational time, Dice Overlap Index, and Jaccard T animoto C oefficient Index. The proposed CBS combined with interval type‐2 fuzzy based clustering produces a sensitivity of 0.7143 and specificity of 0.9375, which are far better than the conventional techniques such as kernel based, entropy based, graph‐cut based, and self‐organizing maps based clustering. Appreciable segmentation results of tumor region that enhances clinical diagnosis is made available through this article and two of the radiologists who have hands on experience in the field of radiology have extended their support in validating the efficiency of the proposed methodology and have given their consent in utilizing the proposed methodology in the processes of clinical oncology. 相似文献
19.
Serio Dawn; Singh Satya P.; Cartas Maria A.; Weber Irene T.; Harrison Robert W.; Louis John M.; Srinivasan Alagarsamy 《Protein engineering, design & selection : PEDS》2000,13(6):431-436
The processing of precursor proteins (Gag and Gag-pol) by theviral protease is absolutely required in order to generate infectiousparticles. This prompted us to consider novel strategies thattarget viral maturation. Towards this end, we have engineeredan HIV-1 virion associated protein, Vpr, to contain proteasecleavage signal sequences from Gag and Gag-pol precursor proteins.We previously reported that virus particles derived from HIV-1proviral DNA, encoding chimeric Vpr, showed a lack of infectivity,depending on the fusion partner. As an extension of that work,the potential of chimeric Vpr as a substrate for HIV-1 proteasewas tested utilizing an epitope-based assay. Chimeric Vpr moleculeswere modified such that the Flag epitope is removed followingcleavage, thus allowing us to determine the efficiency of proteasecleavage. Following incubation with the protease, the resultantproducts were analyzed by radioimmunoprecipitation using antibodiesdirected against the Flag epitope. Densitometric analysis ofthe autoradiograms showed processing to be both rapid and specific.Further, the analysis of virus particles containing chimericVpr by immunoblot showed reactivities to antibodies againstthe Flag epitope similar to the data observed in vitro. Theseresults suggest that the pseudosubstrate approach may provideanother avenue for developing antiviral agents. 相似文献