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Polymer-nanocarbon composites: a promising strategy for enhanced performance of organic solar cells
The exigency for sustainable and clean energy resources has led to profound research in development of various generations of solar cells, aiming to control the over-exploitation of fossil fuels and subsequently limit environmental degradation. Among the fast-emerging third-generation solar cells, polymer solar cell technology has gained much consideration due to its potential for achieving economically feasible, lightweight, flexible solar energy harvesting devices. As a predominant research area, at present, the major concerns regarding polymer solar cells include improving conversion efficiency, enhancing absorption bandgap in polymers, limiting photochemical degradation, and remediating low dielectric constant. Nanocarbon materials can be effectively blended with polymers and have been widely reported to enhance the performance of polymer solar cells owing to their desirable characteristics like high electrical conductivity, mechanical strength, thermal stability, non-toxicity, large specific surface area, flexibility, and optical transparency. In this review, we briefly discuss various conjugated polymer-nanocarbon composites, including polymer/graphene derivatives, polymer/graphene quantum dots (GQD), and polymer/carbon nanotubes (CNTs), elucidating their roles in the performance enhancement of polymer solar cells (PSCs). Graphical abstract: (Figure presented.). The Author(s) 2023. -
Dynamic linkage among crude oil, exchange rates and P/E ratio: The case of India /
International Journal of Pure And Applied Mathematics, Vol.119, Issue 18, pp.1-14, ISSN No: 1314-3395. -
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Microscopic, pharmacognostic and phytochemical screening of Epiphyllum oxypetalum (dc) haw leaves /
Journal of Pharmacognosy And Phytochemistry, Vol.7, Issue 6, pp.972-980, ISSN No: 2349-8234. -
Investigation on the phase transformation and lattice parameters of Sn2+, Cu2+, La3+ and Ce4+ ions doped titania: characterization and solar light activity study /
International Journal For Light And Electron Optics, Vol.183, pp.496-507, ISSN No: 0030-4026. -
FORMATION OF REDDY IDENTITY IN SOUTHERN KARNATAKA 1900-2000 CE
Reddy is the name of a socio-economically and politically dominant community found in Southern India. Today one of the largest single community grouping in south India in general and Andhra Pradesh in particular is Reddy community. They are generally considered traditional village headmen. They had a remarkable history since the period of shatavahanas of 2nd century BCE and the various people from this community have helped people in large way throughout the period and they are socially committed and economically enterprise. Historically the people of the Reddy community had appears some were very wealthy Landowners and Businessmen. Famous Kings, Awardees, Academics, Scientists & Civil Servants, Business Leaders & Entrepreneurs, famous Politicians, Entertainers & Film Professionals, Freedom Fighters, Activists & Philanthropists, Poets and Writers and many more. Though the community regarded their ancestors belongs Andhra Pradesh Telugu as their mother tongue, they assimilated with the regional culture of Karnataka and became proficient in Kannada language too. The community played major role in political arena and became one among the makers of modern Karnataka. Since 1900 their Political identity was expressed through political associations, Freedom movement, and backward class movement and pressurizing for establishment responsible government in Mysore region. Socially the community has been identified as an important caste in south India. The marriage ceremony is sanctified through the authorization of Brahmana, Dasayya. The community has the complex setup within itself because they are in large number. They have peculiar social practices of the appreciation of Brahmanical ideas and process of sankritization is rooted in the original beliefs of Reddy community, The Practice of bride price, widow remarriage, the Brahmin priest not invite to their marriage occasion by some sub castes and many more. The community extended its liberal attitude towards improving the status of women has resulted in arising of many women as industrialists, artists, scientists, physicians, realtors, sports persons and scholars. Economically they are committed to land and agriculture. Culturally the community has predominant followers of the Hinduism with Veerashaiva, Vaishnava and Shaktha sects as the most important faiths. Their annual pilgrimage is to the temple of Shrishaila Mallikarjuna. Yogi VemanaReddy and HemaReddy Mallama were as the legends. The Brahmanical idenitity is not observed and accepted by all denomination of Reddys. The ??Guru Paramapare also exists among the Reddy communities. Each sub caste has to pay their homage to their respective Gurus, who preside over the Matha. The festivals celebrated by the community like Bandi Devara Habba and Makkala Dyavaru are the most specific ones. It has to be accepted as liberation from some hierarchical control and assertion of a community attempting to carve a certain niche status which resulted in a form of monastic tradition or Gurupeeta tradition since the last two decade in Karnataka. Being the promoters of education and literature they established schools, colleges, training centers, hostels and study centers. They are socially advanced, economically developed, politically organized and culturally established. Thus they become influential factor in formation of social-political-economic identity in southern Karnataka. -
Spatial analysis of CO poisoning in high temperature polymer electrolyte membrane fuel cells
The improved tolerance of the High Temperature-Polymer Electrolyte Membrane Fuel Cell (HT-PEMFC) to CO allows the use of reformate as an anode feed. However, the presence of several per cent of CO in the reformate, which is inevitable particularly in on-board reformation in automobiles, which otherwise demands complex systems to keep the CO level very low, will significantly lower the cell performance, especially when the HT-PEMFC is operated at 160 C or below. In this study, a three-dimensional, non-isothermal numerical model is developed and applied to a single straight-channel HT-PEMFC geometry. The model is validated against the experimental data for a broad range of current densities at different CO concentration and operating temperatures. A significant spatial variation in current density distribution is observed in the membrane because the CO sorption is a spatially non-homogeneous process depending on local operating conditions and dilution of the H2 stream. To investigate the local spatial effects on HT-PEMFC operation, the model is applied to a real cell of size 49.4 cm2 with an 8-pass serpentine flow-field at the anode and the cathode. The membrane and anode catalyst layer are segmented into 5 array to investigate the spatial resolution of the polarization curves, H2 concentration, current density, and anode polarization loss. The simulation results show that the presence of CO in the anode feed reduces cell performance, however, the results reveal that uniformity in current density distribution in the membrane improves when the cell is operated in potentiostatic mode. The results are discussed in detail with the help of several line plots and multi-dimensional contours. The study also emphasizes on the importance of optimizing the reformate anode feed rate to improve cell performance. 2020 Hydrogen Energy Publications LLC -
Optimization of graded catalyst layer to enhance uniformity of current density and performance of high temperature-polymer electrolyte membrane fuel cell
The optimal use of catalyst materials is essential to improve the performance, durability and reduce the overall cost of the fuel cell. The present study is related to spatial distributions of current and overpotential for various graded catalyst structures in a high temperature-polymer electrolyte membrane fuel cell (HT-PEMFC). The effect of catalyst gradient across the catalytic layer (CL) thickness and along the channel and their combination on cell performance and catalyst utilization is investigated. The graded catalytic structure comprises two, three, or multiple layers of catalyst distribution. For a total cathode catalyst loading of 0.35 mg/cm2, higher loading near the membrane presents improved cell performance and catalyst utilization due to reduced limitations caused by oxygen and ion diffusions. However, non-uniformity in the current distribution is significantly increased. The increase in the catalyst loading along the reactant flow provides a substantially uniform current density but lower cell performance. The synergy of varying catalytic profiles across the CL thickness and along the cathode flow direction is investigated. The results emphasize the importance of a rational design of cathode structure and mathematical functions as a strategic tool for functional grading of a CL towards improved uniform current distribution and catalyst utilization. 2021 Hydrogen Energy Publications LLC -
Selective subset of relative density feature extraction algorithm for unconstrained single connected handwritten numeral recognition /
Australian Journal of Basic and Applied Sciences, Vol.8, Issue 6, pp.315-321, ISSN No: 1991-8178. -
Zone based relative density feature extraction algorithm for unconstrained handwritten numeral recognition /
Journal of Theoretical and Applied Information Technology, Vol.64, Issue 1, pp.304-314, ISSN No: 1992-8645 (Print), 1817-3195 (Online) -
EFFECT OF SECOND SOUND ON THE ONSET OF RAYLEIGH-B??NARD-MARANGONI MAGNETO CONVECTION
The effects resulting from the substitution of the classical Fourier law by the non-classical Maxwell-Cattaneo law in Rayleigh-B??nard-Marangoni convection in an electrically conducting Newtonian fluid are studied using the Galerkin technique. In the case of Rayleigh??B??nard convection, the eigenvalue is obtained for free-free, rigid-free and rigid-rigid velocity boundary combinations with isothermal and adiabatic boundaries. In the case of Marangoni and Rayleigh-B??nard-Marangoni convection the eigenvalues are obtained for an upper free / adiabatic and a lower rigid / isothermal boundaries. A linear stability analysis is performed. The influence of various parameters on the onset of convection has been analyzed. The classical approach predicts an infinite speed for the propagation of heat. The present non-classical theory involves a wave type heat transport (SECOND SOUND) and does not suffer from the physically unacceptable drawback of infinite heat propagation speed. It is found that the results are noteworthy at short times and the critical eigenvalues are less than the classical ones. -
An Empirical Analysis of Price Discovery in Spot and Futures Market of Gold in India
The broadest classification of the Indian financial market can be made in terms of commodity market, stock and security markets and foreign exchange market. Commodity markets are markets where raw or primary products are exchanged. These raw commodities are traded on regulated commodity exchanges, in which they are bought and sold in standardized contracts. Gold is a commodity which has been undergoing very serious price fluctuations in recent years. It has had its own impact on commodity trading too. Price discovery process of gold has always been a matter of wide discussion among researchers and policy makers. In this context this study aims at analyzing the price discovery process of Gold in Indian commodity market. It also looks into the volatility impact of futures price on spot price as well as the volatility impact of spot price on futures price. The study is completely based on the secondary data collected from the official website of NCDEX. The data extend for a period ranging from 23rd April 2009 to 29th December 2011. The daily data of spot and futures prices of gold during the period is taken into account. Various econometric tools are employed to test the hypotheses set. The VAR model result confirms the unidirectional relationship runs from the spot market to the futures market of gold in India. It reveals co integration and dynamic relationship between spot and futures markets of gold. The result of GARCH model implies that both futures as well as spot markets do have significant impact in the price volatility of gold in India. The result of VECM tells that spot market is dominant in the price discovery process which is a clear indication of the fact that spot market of gold is information efficient in India. The result is of great significance for the investors who wish to improve portfolio performance. With regard to policy making, a better understanding of the interconnectedness of these markets would be useful for the policy makers who coordinate the stability of financial markets. For marketers, it provides a reliable forecast of spot prices in the future to allow them to effectively manage their risks in the production or marketing process. The unprecedented uptrend in the price of gold and high volatility in recent years provides room for some important social implications. -
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Review on persistent challenges of perovskite solar cells stability
Today Perovskite solar cell (PSC) has achieved efficiency close to 26%, surpassing the efficiencies of well- known Dye-Sensitized Solar cells (DSSC), CdTe-based solar cells, etc. Ease of preparing perovskite solutions and convenient deposition technique has given them added advantage over other contemporary competitors. This has also made them an economically feasible option. Since the inception of PSCs in 2009, a lot of improvements have been done in various aspects like composition, synthesis technique, fabrication method, and interface study. However, today it is crucial to think about the commercialization of PSCs. In this direction, the stability of PSCs has been a long-standing question. This review focuses on the key aspects of perovskite stability. Challenges posed by environmental factors like moisture, oxygen, temperature, and light are still unanswered. The lead toxicity of PSCs demands a potential substitute of lead with no compromise in their efficiency. The lead-free approach of PSCs and their commercialization has been discussed separately. A suitable emphasis has been given to the encapsulation of solar cells, as we find it a necessary part of the future commercialization process. This review has been addressed with an ideology to provide overall knowledge on the stability issues and challenges concerned with the PSCs, to attract young research community towards this emerging field. 2021 International Solar Energy Society -
Biogenic synthesis of g-C3N4/Bi2O3 heterojunction with enhanced photocatalytic activity and statistical optimization of reaction parameters /
Applied Surface Science, Vol.494, pp.465-476, ISSN No: 0169-4332. -
Integrated Effect of Flow Field Misalignment and Gas Diffusion Layer Compression/Intrusion on High Temperature - Polymer Electrolyte Membrane Fuel Cell Performance
Misalignment in the flow field plates of High-Temperature Polymer Electrolyte Membrane Fuel Cell (HT-PEMFC) due to manufacturing tolerances, assembly process, or unavoidable vibration during the cell operation is contemplated its performance and durability. This study investigates the effect of flow field plate misalignment and its concomitant impact with varying the clamping pressures on HT-PEMFC operation. The study considers six degrees of cathode flow field misalignment, varying from 0% to 100% with respect to the anode flow field. Clamping pressures ranging from 1 to 2 MPa are applied to the various cases of misalignment to study their effect on GDL deformation and intrusion into the channels. The structural analysis shows that as the misalignment increases from 0 to 100%, the GDL compression increases from 26.72% to 37.75% for 1 MPa, 40.07% to 56.63% for 1.5 MPa, and 53.43% to 75.51% for 2 MPa, owing to the increase in compression approximately by 41% from their base cases and it is also crucial to note that GDL compression exaggerates at higher clamping pressures. The misalignment results in the sagging of Membrane Electrode Assembly (MEA), and the amplitude of wave nature is proportional to the degree of misalignment and clamping pressure, indicating the misalignment is the sole factor for structural changes. As a result, considerable variance in current distribution and average value is observed, i.e., at operating voltage 0.5 V, the current density drops from 4472.7 to 4264.4, 4420.7 to 4211.8, and 4374.1 to 4161.3 A m?2 from cases 1 to 6 for clamping pressures 1, 1.5, and 2 MPa, respectively, resulting in a 4.7% loss in performance. According to the observations, a misalignment of 60% is tolerable, with minimal performance loss and negligible non-uniformity in cell distributions. 2022 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited. -
PERCEPTION OF RETAILERS ON ADOPTING GESTURE CONTROLLED INTERACTIVE ADVERTISING AND DIGITAL DISPLAYS IN INDIA
In the advertising world, everything from billboards, to taxi signs to supermarket displays are going digital. Interactive floor advertising in malls is all the rage, especially in Western and Far East countries. Retailers across the world have been investing on gesture controlled interactive visual display systems to stand out from the crowd and turn their retail locations into a destination for customers. They use it as a means for sophisticated marketing solutions, such as, product advertising, retail merchandising, point-of-sale promotions, campaigning etc, resulting in transformation of retail customer experience. Such interactive elements not only help drive traffic to the desired location and keep visitors there for longer, but also help drive core business philosophies and return on investments. Well, all these are quite appealing to anyone in the retail business to bounce and invest with a hope to harvest, but, it has not gained as much coerce as one would expect with Indian retailers. So, it would be prudent to find their perception towards adopting this innovative marketing strategy. It is intended that the findings of this research, about the perceptions of adopting gesture controlled interactive advertising and digital displays, will be useful to retailers, consumer packaged goods organizations, distributors, mall owners, advertising agencies etc. It would help them to assess their current marketing strategies and to gain knowledge of pros and cons of incorporating this innovative form of advertising. These findings could also be used for any corrections to the investments already made in this area. The rest of the content in this report details out the research conducted in this regard followed by a conclusion. The first chapter introduces to the research topic, justifies & highlights the problem poser and the goal of the work presented in the dissertation. It also highlights the significant contributions from the investigation. The second chapter presents a critical appraisal of the previous work published in the literature pertaining to the topic of the investigation. The chapter three discusses the problem statement, overall methodology used in order to achieve the objectives of this research, present the sample characteristics, development of measurement instrument, pilot study, research variables, data collection procedure and finally the scope and limitations of the study. The fourth chapter is the penultimate chapter of the dissertation and includes a thorough evaluation of the investigation carried out. It focuses on the detailed analysis of the data obtained from the field from different retailers. Finally, the fifth chapter provides a brief report of the work carried out forms the first part of the Chapter. Conclusions derived from the logical analysis is presented and clearly enumerated. Suggestions from current findings and scope for future work are also stated in the last part of the Chapter. Key words: Retail, Interactive Advertising, Gesture Control, Digital Display. -
EFFECT OF CORIOLIS FORCE AND NON UNIFORM BASIC TEMPERATURE GRADIENT ON THE ONSET OF RAYLEIGH BENARD CONVECTION IN SECOND ORDER FLUID WITH GENERAL BOUNDARY CONDITION
The effect of coriolis force and non uniform basic temperature gradient on the onset of Rayleigh B??nard convection in Second order fluid with general boundary conditions are studied using the Galerkin technique. The effects of one linear and five nonlinear basic temperature gradients are studied on the onset of convection. A linear stability analysis is performed. The influence of various parameters on the onset of convection has been analyzed and their comparative influence on onset is discussed. The study of the problem with general boundary conditions for velocity and temperature indicates that the results of the previous studies for different boundary conditions are obtained as limiting cases for the present studies.