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Microcannular electrode/polymer electrolyte interface for high performance supercapacitor
In the present work, the ionic resistance in the activated carbon (AC) electrode and blend polymer electrolyte (BPE) interface is reduced by tuning binder and BPE. A unique microcannulars channel connecting AC, binder and gaur gum (GG)/polyvinylalcohol (PVA) electrolyte is developed for easy Li+ movement. The use of AC derived from areca nut and natural GG as a binder makes the developed method more environmentally sustainable. The presence of microcannular structures on the electrode surface and BPE was confirmed using SEM and TEM analysis. Combined DSC-TGA data for BPE showed that PVA provides the mechanical support to jelly guar gum. The ionic conductivity, activation energy, dielectric studies were studied to understand the electrode/electrolyte interface mechanism. Dielectric studies revealed that the unique pathway of microcannular structures reduces the charge transfer resistance significantly at the interface. Optimized BPE was used in the fabrication of supercapacitor and specific capacitance was found to be 542 Fg-1. The time constant was 0.4 s and showed consistent cyclic pattern during galvanostatic charge/discharge studies with 99% Columbic efficiency. 2020 Elsevier Ltd -
Pt nanoflower-poly(aniline) electrode material with the synchronized concept of energy storage in supercapacitor
Electrochemically deposited porous film of poly(aniline) (PANI) on stainless steel (SS) current collector is employed as the support for electrodeposition of platinum (Pt). PANI facilitates the formation of Pt nanoflowers with an enhanced electrochemically active surface area compared with sub-micron size Pt particles deposited on the bare SS electrode. Hence, a new concept Pt nanoflower-PANI electrode materials with synchronization between redox mode in PANI and double-layer mode of charge storage in Pt nanoflower is discussed. Remarkably, Pt is distributed like a nano-flower on the surface of PANI and prevents PANI from stripping during the charge-discharge process, thereby minimizing the issue of stripping in conducting polymer-based electrodes. Owing to the highly porous surface morphology of Pt nanoflowers as observed in SEM, the Pt-PANI/SS electrode shows excellent electrochemical performance than PANI/SS electrode towards supercapacitor application. The electrode materials are characterized using X-ray and X-ray photon spectroscopy (XPS), which shows dual amorphous and crystalline properties. Dielectric studies of Pt-PANI/SS electrodes were carried out to understand electrode/electrolyte interface behavior. In the fabricated supercapacitor, the cyclic voltammetry studies showed quasi-rectangular shape characteristics at slower scan rates with a specific capacitance of 926 Fg?1. Charge-discharge studies showed good cyclic stability and coulombic efficiency. 2022 Elsevier B.V. -
Pt nanoflower-poly(aniline) electrode material with the synchronized concept of energy storage in supercapacitor /
Applied Surface Science, Vol.589, ISSN No: 0169-4332.
Electrochemically deposited porous film of poly(aniline) (PANI) on stainless steel (SS) current collector is employed as the support for electrodeposition of platinum (Pt). PANI facilitates the formation of Pt nanoflowers with an enhanced electrochemically active surface area compared with sub-micron size Pt particles deposited on the bare SS electrode. Hence, a new concept Pt nanoflower-PANI electrode materials with synchronization between redox mode in PANI and double-layer mode of charge storage in Pt nanoflower is discussed. Remarkably, Pt is distributed like a nano-flower on the surface of PANI and prevents PANI from stripping during the charge-discharge process, thereby minimizing the issue of stripping in conducting polymer-based electrodes. -
Learning and assessment of English language in expeditionary learning (EL) among undergraduate university students
This paper aims to enhance readers understanding of the Learning and Assessment of English language through Expeditionary Learning (EL) Model. The study presents the findings and implications of an experiment conducted among undergraduate university students. The design principles of EL Model are enumerated along with the kinds of expeditions being explained. Learning and Assessment in EL is elaborated by detailing the Facilitators role and the classroom environment required for implementation of this model. The advantages of using the EL model for Learning and Assessment is analyzed by the investigator and presented with findings from the experiment. The study also makes observations that the EL model is a learner-centric model and the psychological principles of learning is incorporated in the design principles of the model. 2020, IJSTR. -
Gold jewellery making and migrant labour force in Kerala
The extent of the gold jewellery market in Kerala has widened and consumption patterns have drastically altered. The increasing presence of migrant workers in the industry is a direct consequence of the deregulation of the gold industry in the early 1990s. While resorting to a labour process framework, this paper elucidates the process of recruitment and the composition of workforce. The empirical data is based on the findings and observations gathered through intensive fieldwork conducted during the course of three years, from 2010 to 2013, in the gold jewellery making industry in Thrissur and Kozhikode districts. This work also relies on a larger data set, the Inter-State Migrant Survey conducted by the Centre for Development Studies in 2012, which collected data on migrant workers from four districts of Kerala. 2019 Economic and Political Weekly. All rights reserved. -
Gold jewellery making and migrant labour force in Kerala /
Economic & Political Weekly, Vol.54, Issue 28, pp.106-113, ISSN No: 2349-8846. -
Need for an Innovative Method for Second Language English Learners with Special Reference to Syntax and Grammar
Educational Quest Vol. 3, No. 2 pp. 183-192, ISSN No. 0976-7258 -
Nanoencapsulation of Ru(p-cymene) Complex Bearing Ginger-based Natural Product into Liposomal Nanoformulation to Improve Its Cellular Uptake and Antiproliferative Activity
The organometallic compounds are prospective candidates in the row of developing metallochemotherapeutics with the aim of overcoming the limitations of platinum drugs. In order to explore the anticancer properties of organometallic compounds with the natural medicines, two Ru(II)-p-cymene complexes containing the natural products, viz., 6-gingerol (6G) and benzylated-6-gingerdione (B-6GD) have been synthesized and characterized well. The phenolic group of the Ru(6G) complex facilitates its higher cell-free antioxidant activity than its analogue complex. Also, the same complex shows higher cytotoxicity toward A549 lung and HeLa-S3 cervical cancer cells than the Ru(B-6GD) complex but lower cytotoxicity toward A2058 metastatic melanoma cancer cells. Both complexes are shown to easily accumulate in melanoma cancer cells, and their degree of cytotoxicity in the same cells is found to be positively correlated with cell uptake. The cytotoxicity of complexes arises from their intracellular activity, mainly due to the induction of singlet oxygen production in cancer cells. The subcellular fractionation study shows that mitochondria and ER-Golgi membranes might be their predominant targets. Also, the mechanistic investigation revealed that Ru(B-6GD) induces caspase-dependent non-apoptotic cell death whereas Ru(6G) can induce caspase-independent non-apoptotic cell death. Furthermore, both complexes are found to moderately alter the adhesion properties of cancer cells, which is beneficial for antimetastatic treatment. Despite the potential pharmacological activity, Ru(6G) is encapsulated into polymer-supported liposomes to reduce its toxicity and further improve its anticancer potency. The ?-conjugated yne-ene chain of polydiacetylene aids in the development of a stable nanoformulation, which achieved a slow release of the complex. Most importantly, the cancer cell uptake of the liposome-encapsulated Ru(6G) complex is 20 times enhanced and the total ROS formation in cancer cells is significantly increased compared to the non-encapsulated complex. However, the nanoformulation does not alter the antimetastatic potency of the encapsulated complex. 2022 American Chemical Society. All rights reserved. -
Safe cloud: Secure and usable authentication framework for cloud environment
Cloud computing an emerging computing model having its roots in grid and utility computing is gaining increasing attention of both the industry and laymen. The ready availability of storage, compute, and infrastructure services provides a potentially attractive option for business enterprises to process and store data without investing on computing infrastructure. The attractions of Cloud are accompanied by many concerns among which Data Security is the one that requires immediate attention. Strong user authentication mechanisms which prevent illegal access to Cloud services and resources are one of the core requirements to ensure secure access. This paper proposes a user authentication framework for Cloud which facilitates authentication by individual service providers as well as by a third party identity provider. The proposed two-factor authentication protocols uses password as the first factor and a Smart card or Mobile Phone as the second factor. The protocols are resistant to various known security attacks. Springer India 2016. -
Predicting energy source diversification in emerging Asia: The role of global supply chain pressure
This study investigates energy diversification trends in six Emerging Asian countries from 1998 to 2021 while exploring the predicting effects of the global supply chain pressure, total investment, innovation, economic growth, and globalisation on energy diversification. This study considers the Kernel-Based Regularized Least Squares (KRLS) estimations and prediction models (Adam and Stochastic Gradient Descent optimisers). The impacts of global supply chain pressure and total investment on energy diversification are positive. Innovation also emerges as crucial factor to enhance energy diversification. Deeper integration into the global economy (globalisation) and economic growth strengthen energy diversification. The study underscores the importance of tailored policies, advocating for investments in innovation, targeted total investment, and inclusive growth strategies to address energy diversification in emerging Asian countries. 2024 Elsevier B.V. -
Sustainable synergies: Performance evaluation of cement mortar with red mud and industrial by- products
This study examines the potential of red mud, a by-product of the alumina industry, as a partial replacement for cement in mortar, aiming to advance sustainable construction in line with UN SDGs 9, 11, and 12. Red mud was incorporated at 1090 % by weight, together with 4 % Ground Granulated Blast Furnace Slag (GGBS) or 4 % fly ash as supplementary cementitious materials. The mixes were tested for compressive strength, flexural strength, water absorption, apparent porosity, and bulk density at 3, 7, and 28 days. The optimum performance was achieved with 3040 % red mud and GGBS, yielding a 28-day compressive strength of 19.29 MPa and flexural strength of 4.55 MPa, outperforming both control and fly-ash-based mixes. Higher red-mud levels increased water absorption (approximately 18 %) and porosity (approximately 15 %). Microstructural analyses (SEM-EDX, XRD, FTIR) confirmed the formation of Calcium Silicate Hydrate (C-S-H), Calcium Aluminate Hydrate (C-A-H), and ettringite phases. The research introduces a novel tri-component binder system (cement-red mud-GGBS/fly ash) that transforms industrial waste into a durable, low-carbon construction material, promoting resource circularity and carbon reduction. 2025 The Authors -
Blast resistance of steel plate shear walls designed for seismic loading
Since a blast loading or explosion can create nonlinear wave action and impact pressure on a structure, it necessary to construct a structure to resist blast loading as like other loads. In this study the nonlinear behaviour of a blast loading is simulated by calculating the pressure diagram with respect to time under the guidance of IS 4991-1968, code for "Criteria for Blast Resistant Design of Structures for Explosions above Ground". The study carried out for different charge weight (100kg TNT, 200kg TNT and 400kg TNT) and standoff distances of 20metre. Nonlinear behaviour of a Blast loading to steel structures with shear plates of thickness 6 mm, 8 mm and 10 mm are modelled in ETABS and the analysis is carried out to obtain base shear, story displacement, story deformation pattern, column forces, etc. Published under licence by IOP Publishing Ltd. -
Sustainability Concepts in the Design of Tall Structures
Construction industry is a rapid growing industry with various new technologies coming into practice. Sustainability concept is also a call for the present generation as many natural resources are getting exhausted. Thus the new era of development of Tall Structures with respect to Sustainability concept is being studied by concentrating on the Structural systems that can be adopted for construction of the same. In the present study we have considered two different 3D RC frame structural systems i.e., normal Beam-Column structural system and Outrigger structural system. The following two systems were modelled in ETABS 15.2 software in seismic zone V with three different heights that is 150m (50 storeys), 240m (80 storeys) and 300m (100 storeys). Response spectrum analysis is carried out considering Earthquake forces and the results are tabulated for maximum storey displacement and maximum storey drift. Then finally the structural system which is sustainable in construction of Tall structures is identified. 2020, Springer Nature Switzerland AG. -
Effect of different base isolation techniques in multistoried rc regular and irregular building
Base confinement system for a structure is acquainted to decouple the building structure from possible movement incited by the movement of the seismic tremor, keeping the building superstructures from retaining the quake vitality. Base isolator increases the regular time period of the general structure and diminishes its shear increasing speed reaction to the seismic movement. In this explanatory examination, a ten-storey reinforced concrete (RC) building with lead elastic bearing, high damping elastic bearing and triple-contact pendulum framework bearing is acquainted with the structures, and correlation is made between fixed base and the base-secluded structures. Demonstrating and investigation are conveyed utilizing ETABS 2015 v15.2.2. The investigation examination is performed to check the ampleness of the working against the lateral displacement, inter-storey drift, story shear and story acceleration. It is found from the investigation that reaction of working to lateral load diminishes, while modular period is expanded in both X and Y bearings. Furthermore, it was reasoned that triple grating pendulum bearing is increasingly compelling in examination of different direction utilized in this investigation. Springer Nature Singapore Pte Ltd 2021. -
Eco Friendly Nitration of Toluene using Modified Zirconia
Bulletin of Chemical Reaction Engineering & Catalysis Vol. 7, No.3, pp.205-214 ISSN No. 1978-2993 -
Modified ceria as a substitute for sulfuric acid in the liquid phase nitration of toluene
Ceria, sulfated ceria, ceria-zirconia and sulfated ceria-zirconia catalysts were prepared via the co-precipitation method and calcined at 823 K. The catalysts were characterized by XRD, BET surface area, FTIR, TGA and EDAX. The acidity of the catalysts was studied by pyridine adsorbed FTIR. All the peaks in XRD correspond to the cubic fluorite structure of ceria. The crystallite size of the catalysts was found to be 4-8 nm. Incorporation of zirconia stabilizes the surface sulfate species and thus increases the sulfate content. Sulfation decreases the surface area, but increases the acidity, leading to enhanced catalytic activity. All the catalysts were found to be stable up to 923 K. Catalytic activities were tested towards the liquid phase nitration of toluene. A maximum conversion of about 34 % is achievable for the nitration of toluene to dinitrotoluene. Solid acids effectively play the role of sulfuric acid in the reaction, assisting the formation of nitronium species. 2012 Akadiai Kiad Budapest, Hungary. -
Biogenic synthesis of g-C3N4/Bi2O3 heterojunction with enhanced photocatalytic activity and statistical optimization of reaction parameters
A facile and efficient biogenic method was adopted to synthesize Bi2O3 and g-C3N4/Bi2O3 nanocomposites using Eichhornia crassipes plant extract. These composites were characterized by various analytical tools such as XRD, FTIR, SEM, TEM and UV-DRS. Bismuth oxide and g-C3N4/Bi2O3 show varied optical and photocatalytic properties due to the differences in their band gap. Here, Box-Behnken design (BBD) combined with Response Surface Methodology (RSM) has been used to optimize the coupled effect of independent parameters for the dye degradation. The synthesized g-C3N4/Bi2O3 nanocomposite exhibit excellent photocatalytic activity for the degradation of malachite green (MG) dye. Total Organic Carbon (TOC) analysis unveiled 78% photomineralization of MG over g-C3N4/Bi2O3 in 5 h. The p-n junction of g-C3N4/Bi2O3 with better oxidative ability and effective charge separation is the primary reason for its improved photocatalytic activity. The modified photocatalyst shows satisfactory catalytic activity and reusability towards photodegradation of common water pollutant MG up to 4 cycles. They offer great potential in the field of photocatalysis due to their superior efficiency and applications in environmental remediation. 2019 Elsevier B.V. -
Investigation on the phase transformation and lattice parameters of Sn 2+ , Cu 2+ , La 3+ and Ce 4+ ions doped titania: characterization and solar light activity study
Nanocrystalline titania and metal ion doped titania systems were prepared by combustion method. Titania exhibited bicrystalline phase consisting of both anatase and rutile. The bicrystalline framework in TiO 2 powders can be conveniently altered by the incorporation of various bivalent/trivalent/tetravalent metal ions like Sn 2+ , Cu 2+ , La 3+ and Ce 4+ . The microstructure development and the influence of small amount of dopants on the resulting structural change have been investigated. p-XRD results confirms the stabilization of anatase phase in the case of Cu 2+ and Sn 2+ doped titania, while the polymorphic interfaces were retained in La 3+ and Ce 4+ doped titania samples. The efficacy of the modified titania was studied on the degradation of Congo Red dye by harvesting solar light. Sn 2+ /TiO 2 shows almost same photodegradation ability as that of pristine TiO 2. Subsistence of catalytic hot spots at the interface of anatase-rutile and the synergistic effect of polymorphic phases explains the enhanced activity of La 3+ /TiO 2 and Ce 4+ /TiO 2 . But the activity of Cu 2+ /TiO 2 was found to be less due to high electron-hole recombination rate. 2019 Elsevier GmbH -
Response surface optimization and process design for glycidol synthesis using potassium modified rice husk silica
Glycerol, an inexpensive by-product from biodiesel production can be converted into many useful products notably glycidol, which has a wide range of uses. In this study, glycidol synthesis has been done using a biowaste mediated catalyst in a single step process. Silica and potassium incorporated silica were synthesized from biowaste rice husk. These catalysts were characterized by different spectroscopic techniques. Basic sites in the catalysts were estimated using temperature-programmed desorption study. Four operational parameters were optimized using Box Behnken Design (BBD) of response surface methodology (RSM). Potassium incorporated rice husk was found to be one of the best catalysts for glycidol production with 60.8% glycerol conversion and 62.9% selectivity within one hour of reaction time. 2020 Elsevier Ltd. All rights reserved. -
A Translator for Indian Sign Boards to English using Tesseract and SEQ2SEQ Model
Language translator for Indian language to English have been developed and it have proven to a challenging domain due to large combination of character in Indic scripts such as Tamil, Kannada and Hindi. In this paper we propose a system which captures Indian printed character and translates it into English, we have discussed the various method and machine learning model that was used to build this system with an accuracy of 87%. 2021 IEEE.