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Enhanced visible light harvesting in dye-sensitized solar cells through incorporation of solution-processable silver plasmons and anthracite-derived graphene quantum dots
The major setback for the enhanced performance of DSSC is the narrow absorption window and the interfacial exciton recombination. Therefore, in this work, the photovoltaic performance of dye-sensitized solar cells has been improved by the synergistic effect of anthracite-derived graphene quantum dots and silver plasmons. GQD and Ag coupled photoanodes were fabricated by a facile solution processable process under room temperature. The as-fabricated DSSC TiO2/Ag/GQD (TAG) exhibited an enhanced power conversion efficiency of 10.5 % with a current density of 22.40 mAcm?2 measured under solar irradiation of 100 mWcm?2 with AM 1.5G. An enhancement surpassing 30.5 % was obtained for the champion cell when compared to the pristine TiO2 based DSSC. Furthermore, this study emphasizes developing a cutting-edge approach for the high-quality use of fossil fuel-derived graphene quantum dots in energy conversion systems, thereby encouraging the green conversion of fossil fuels and broadening the potential of anthracite coal's utilization in energy conversion applications. 2024 Elsevier Ltd -
Fossil fuel derived GQD as a photosensitizer in dye-sensitized solar cells
Solar energy is an abundantly available renewable source, and several generations of photovoltaic cells have been developed for harnessing it. Dye-sensitized solar cells (DSSC) are viable and potent solar energy harvesters. Sensitizer, a vital part of DSSC, has been researched for years. Alternatively, fossil fuel-Lignite is one of the world's least explored energy sources. Unfortunately, it has been used as a fuel for power generation and tagged as a pollutant. Therefore, in this study, we use lignite-derived graphene quantum dots (GQD) as a DSSC sensitizer and attempt to add value. GQDs with varied bandgaps were obtained and used as sensitizers, and a maximum PCE of 2.87 % was obtained. Additionally, GQD sensitizers were exposed to UV light for 48 h, and the fabricated device exhibited 2.90 % efficiency, showing the photostability of GQDs. Furthermore, the device showed a higher Rrec of 166.57 ?, substantiating the better performance of DSSC. Thus, sensitizers derived from lignite showed a novel use for feedstock previously used for combustion. 2023 Elsevier B.V. -
Extraction and characterization of preformed mixed phase graphene sheets from graphitized sub-bituminous coal
In present paper, a facile method is reported to extract mixed phase nanometre-sized carbon sheets from sub-bituminous coal. The lattice constants (La and Lc) of sub-bituminous coal were calculated to be 4.82 and 1.41 nm, respectively. The aromatic layers and average number of carbon atoms in the aromatic lamellae were estimated as 5 and 8, respectively. The obtained graphene sheets exhibits broadened D and G band in addition to a very broad 2D bump. Defect to graphitic ratio is found to be 0.54 indicating less disorder in graphene nanomaterial formed. This is further corroborated by (ID/ID') ratio which was observed to be 3.40, confirming the defect has originated from boundary. The SEM analysis reveals the formation of large number of carbon layers with different shape in the nanometer scale range. Formation of graphene dots in the shape of hexagonal, spherical, graphene layers and corn shaped carbon nanotubes are noticed in the TEM image. -
Lignite-derived nanocarbon as surface passivator and cosensitizer in dye-sensitized solar cell
Interfacial exciton recombination and narrow absorption region are two bottlenecks that limit the performance of a dye-sensitized solar cell (DSSC). The present study focuses on improving the solar cell's efficiency by utilizing a lignite-derived nanocarbon that behaves as a surface passivator and cosensitizer. Incorporating nanocarbon enhanced the spectral absorption region of the N719 dye with a bathochromic shift and played the role of a cosensitizer. In addition, the quenched photoluminescence spectra revealed that nanocarbon also aids in the swift transfer of electrons to the conduction band of TiO2 by reducing the exciton recombination and acting as a surface passivator. On measuring the fabricated DSSC under AM 1.5G irradiation with the intensity of 100 mW/cm2, the nanocarbon-based device exhibited an efficiency (?) of 9.02% with a photocurrent density of 20.45 mA/cm2, outperforming the pristine device (? = 6.21%). An enhancement of 45% in the power conversion efficiency was achieved. Thus, the results unveiled that nanocarbons derived from pollution-causing fuel synergistically aided in enhancing the performance of DSSC. 2024 Elsevier Ltd -
Development and Validation of the Social Media Self-Esteem Scale for Adolescents
Development of the self is a vital aspect during the period of adolescence. Interaction with peers contributes to the development of various aspects of self. Due to the technological advances in todays times, adolescents interact with their peers through social media sites and portals. It is essential to study this development in light of the increasing use of social media by adolescence. Thus, the study aimed at developing an item pool to tap the construct of social media influencing self-esteem of adolescents following the procedure of tool construction. Participants included adolescents ranging between 16 to 18 years of age, who have at least one social media account for personal use. There were 110 participants for the first phase and 397 participants for the second phase of the study. The scale has eight items with the overall reliability of .7. It indicates a fitting measure of self-esteem influenced by social media, with looking-glass self theory, according to which individuals develop their self, based on their perceptions of others responses to their behaviour. Copyright 2020, IGI Global. -
AttGRU-HMSI: enhancing heart disease diagnosis using hybrid deep learning approach
Heart disease is a major global cause of mortality and a major public health problem for a large number of individuals. A major issue raised by regular clinical data analysis is the recognition of cardiovascular illnesses, including heart attacks and coronary artery disease, even though early identification of heart disease can save many lives. Accurate forecasting and decision assistance may be achieved in an effective manner with machine learning (ML). Big Data, or the vast amounts of data generated by the health sector, may assist models used to make diagnostic choices by revealing hidden information or intricate patterns. This paper uses a hybrid deep learning algorithm to describe a large data analysis and visualization approach for heart disease detection. The proposed approach is intended for use with big data systems, such as Apache Hadoop. An extensive medical data collection is first subjected to an improved k-means clustering (IKC) method to remove outliers, and the remaining class distribution is then balanced using the synthetic minority over-sampling technique (SMOTE). The next step is to forecast the disease using a bio-inspired hybrid mutation-based swarm intelligence (HMSI) with an attention-based gated recurrent unit network (AttGRU) model after recursive feature elimination (RFE) has determined which features are most important. In our implementation, we compare four machine learning algorithms: SAE + ANN (sparse autoencoder + artificial neural network), LR (logistic regression), KNN (K-nearest neighbour), and nae Bayes. The experiment results indicate that a 95.42% accuracy rate for the hybrid model's suggested heart disease prediction is attained, which effectively outperforms and overcomes the prescribed research gap in mentioned related work. The Author(s) 2024. -
Role of Constructivism Developing Metacognitive Abilities Among Secondary School Students
Research Tracks, Vol-1 (1), pp. 125-128. ISSN-2347-4637 -
Relationship Between Muilti-Media Exposure and Socio-Cultural Awareness of Secondary School Students
Learning Community, Vol-3 (2&3), pp. 233-241. ISSN-0976-3201 -
Is the Electronic Market the Way Forward to Overcome Market Failures in Agriculture?
This paper examines the performance of agricultural markets through analysing the primary data from 856 farm households in six states along with secondary data. It argues that adequate physical and storage infrastructure is crucial even for the functioning of the electronic market, and other related policy measures are needed to have a significant improvement in agricultural marketing. The results indicate that farmers obtained 3.75% higher prices in these markets vis-vis the prices received before selling to these markets. This is significant as the prices plummeted by 8.34% in the manual transactions. 2022 Economic and Political Weekly. All rights reserved. -
Prospective memory in early and established psychosis: An Indian perspective
Individuals affected by psychosis often have deficits in several neurocognitive functions. Prospective memory (PM), the ability to remember to do things, is crucial for activities of daily living, social and occupational functioning, but very few studies have attempted to examine this domain of functioning in people with psychosis, particularly in India. A total of 71 patients with psychosis, (both early and established psychosis), and 140 age, gender and education-matched healthy controls were assessed using the Positive and Negative Symptom Scale, Hospital Anxiety and Depression scale, and Addenbrooke's Cognitive Examination. PM was assessed using the Cambridge Prospective Memory Test and the Prospective and Retrospective Memory Questionnaire (PRMQ). Group differences were evaluated using MannWhitney U-tests. Significantly greater cognitive deficits, higher anxiety and depression were evident in the psychosis group compared with controls. The psychosis group performed significantly poorer on both time- and event-based tests in CAMPROMPT than controls. These differences remained when controlling for age, education, general cognitive functioning and mood. The subjective measure of PM (PRMQ) did not differentiate the two groups. The PM performance of early and established psychosis patients was similar. Comparisons with cross-cultural data (PRMQ UK norms and CAMPROMPT and PRMQ Chinese data) revealed important differences in PM performance. Individuals with psychosis have significant deficits in both time- and event-based PM. CAMPROMPT emerged as a more sensitive PM measure compared with PRMQ. Results from cross-cultural comparisons underscore the need for cultural contextualization of assessments. 2023 The British Psychological Society. -
A novel chemical route for low-temperature curing of natural rubber using 2,4 dihydroxybenzaldehyde: improved thermal and tensile properties
A novel method for chemically curing natural rubber (NR) using 2,4-dihydroxybenzaldehyde (DHB) at low temperatures has been discovered. Adding varying amounts of DHB to NR increases the crosslinking between the NR molecular chains. The chemical reaction between NR molecular chains and DHB was confirmed through Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (NMR) spectra. From the thermogravimetric analysis (TGA), the thermal stability and activation energy of degradation were determined. The variation in glass transition temperature (Tg), as an indication of increased crosslink density, reducing the mobility of rubber chains, has been confirmed through differential scanning calorimetry (DSC). The addition of DHB to latex significantly enhanced the thermal stability of the rubber. An increase in the activation energy of 5.52% was observed upon the addition of 80mL DHB into NRL when compared to the uncured one. Furthermore, the tensile properties, in terms of tensile strength and modulus of elasticity of rubber, were drastically increased through DHB crosslinking. Tensile strength values of rubber were found to increase by reducing its elongation at break due to the formation of crosslinks between the macromolecular chains. NR cured with 80mL DHB exhibited superior tensile and thermal properties among the series of cured samples. By adding 80mL of DHB, the tensile strength increased by 390% and the elongation at break decreased by 10%. The advantage of this curing method is that, it is an effective technique for crosslinking NR directly from NR latex at comparatively low temperature. Graphical abstract: (Figure presented.) Iran Polymer and Petrochemical Institute 2024. -
Investigation of photoluminescence emission from ?-Ga2O3: Ce thin films deposited by spray pyrolysis technique
Ce doped Ga2O3 thin films for different doping concentrations (3 at%, 4 at%, 5 at%, 6 at%, 7 at%, and 8 at%) were deposited by spray pyrolysis method. X-ray diffraction analysis confirmed the crystalline structure as that of monoclinic ?-Ga2O3. The effect of doping on the band gap of the material was studied by UV-Visible spectroscopic method and the thickness of the film and refractive index were measured by ellipsometric technique. The photoluminescence excitation and emission spectra were recorded for pure and doped samples and the energy band scheme with possible radiative and nonradiative transitions were elucidated. Concentration quenching effect was observed, and the underlying mechanism responsible for quenching effect was studied based on Dexter theory. 2021 Elsevier B.V. -
Characterisation of Sn-Cl co-doped ?-Ga2O3 thin films deposited via spray pyrolysis and their application in UV detector devices
Ga2O3, an ultrawide bandgap semiconducting oxide, is currently emerging as a promising candidate for various applications, such as power devices, solar-blind UV detectors, high temperature oxygen sensors and biomedical imaging. One significant limitation hindering the application of Ga2O3 as a wide-bandgap semiconductor is its poor conductivity. In this work, we investigate whether doping with tin and chlorine can mitigate this condition. Sn-Cl co-doped ?-Ga2O3 thin films are deposited on glass substrates using spray pyrolysis technique. The deposited films are subjected to comprehensive analysis, including structural, optical and morphological measurements using techniques like X-ray diffraction, UV-Vis-NIR spectroscopy, X-ray photoelectron spectroscopy and EDX studies. Electrical properties are assessed using the four-probe method and Hall measurements. The best conductivity of 8.86 ??1m?1 is observed when 8.68 at% of Sn and 3.37 at% of Cl were co-doped into Ga2O3 (S(3)) and its optical band gap is calculated to be 4.65 eV. This is about five orders of improvement in conductivity as compared to that of pure Ga2O3 thin film deposited by the same method. Furthermore, we have constructed a deep UV detector utilizing doped ?-Ga2O3 thin films as the semiconducting absorbing layer. The detector demonstrated the highest responsivity of 2.54 10?4 A/W at 260 nm and the corresponding specific detectivity is 1.4 109 Jones. The current research validates the potential of Sn-Cl co-doped ?-Ga2O3 thin film as an excellent choice for UV detector application. 2024 Elsevier B.V. -
Effect of substrate temperature on the properties of spray deposited Ga2O3 thin films, for solar blind UV detector applications
In this work, Ga2O3 thin films were deposited on glass substrates by chemical spray pyrolysis technique at three different substrate temperatures 350 C, 400 C, and 450 C. The structural, optical, morphological and electrical characteristics of the deposited sample thin films were investigated. From the studies, it is understood that by tuning substrate temperature, we can extensively change the properties of the film. Optimum temperature for coating Ga2O3 thin films was understood and the work was extended to demonstrate a simple deep UV detector, working in photoconductive mode. The fabricated device exhibit medium response to UV light at 254 nm. The present work report the fabrication of solar blind UV detector based on Ga2O3 thin film, grown using low cost, easily scalable spray deposition technique. 2022 Elsevier B.V. -
Navigating the emotional maze: Understanding Adolescent suicidal ideation using CNN-LSTM model
Teenage suicidal ideation is on the rise, which emphasizes how crucial it is to recognize and comprehend the variables that contribute to this problem. Convolutional neural networks (CNNs), which are complex machine learning models capable of analysing intricate relationships within a network, are one possible strategy for addressing this issue. In our study, we employed a CNN-LSTM hybrid model to explore the complex relationships between teen suicide ideation and various risk variables, including depression, anxiety, and social support by analysing a substantial dataset of mental health surveys, seeking patterns and risk factors associated with suicidal thoughts. Our objective was clear: identify adolescents prone to suicidal ideation. With 24 parameters and a sample size of 3075 subjects, our model achieved an impressive F1-score of 97.8%. These findings provide valuable insights which helps in developing effective preventive interventions to address adolescent suicidal ideation, finding out the important patterns and risk variables related to suicidal thoughts. The study results offer important direction for developing preventive interventions that successfully address adolescent suicidal ideation. 2024 - IOS Press. All rights reserved. -
Artists' moving image: South Asian trajectories /
Moving Image Review & Art Journal (MIRAJ), Vol.7, Issue 2, pp.191-201, ISSN No: 2045-6298. -
Re-evaluating Emperor Asoka a relational contract theory explanation for economic transformation
Emperor Asoka's rein is considered an important era in ancient Indian history because of the vastness of his empire and the Buddhist elements in his administration. We propose that in addition to these reasons for highlighting Asoka's rein, there is an important economic argument as well. It was during the century or two around Asoka's rule that the subcontinent's economy underwent a transformation from a simple pastoralagricultural economy to a more mature economy with large scale production, specialisation and trade. The element that Asoka introduced into the social relations in his empire is Buddha's Dhamma, which formed and strengthened relational contracts. A key feature of relational contracts is incompleteness of arrangements that is managed by social iterations and formal and informal enforcement mechanisms. Each of these is reflected in Asoka's edicts, the earliest surviving writing samples from the subcontinent. Asoka planned for these measures to ensure political and economic stability. In addition, he also laid the most important foundational material in a rather unique way for all future economic transformations. 2017 Journal of Dharma: Dharmaram Journal of Religions and Philosophies (DVK, Bangalore). -
Corporate social responsibility: Myth and reality
Companies nowadays strive to be socially conscious in the way they do business by taking up corporate social responsibility (CSR) activities besides maintaining profitability. Similarly consumers modulate their purchase choices to be made up of products that have been produced and marketed through socially responsible processes. But the congruence between achieving gain and being responsible to the community has ethical contradictions due to the presence of self interest. This paper proposes to examine the dimensions of this conflict and towards the end suggest a new orientation that foregrounds social responsibility relative to profit or gain. 2013 Journal of Dharma: Dharmaram Journal of Religions and Philosophies (Dharmaram Vidya Kshetram, Bangalore). -
Flourishing and work flow among working adults: A positive investigation from India
The demands in today's organizations are only growing at peaking high levels where turnover and burnout sets out to be major factors that challenge productivity. This is supported by previous findings which have identified turnover and burnout as a consequence of job demands. In today's demanding era of workforce, capacity to work effectively is a key component of employee's health, well-being and growth. Positive emotional and mental state of employees is a predictor of positive organization which will result in high performance, wellbeing and a conducive environment to flourish. Present study deals with workflow and its relationship with employee`s flourishing. This paper aims to explore the relationship between flourishing and experiences of work flow among working adults (n=105). Relationship among variables was analyzed through correlation and regression analysis. Results indicate that there is significant positive correlation between flourishing and experience of work flow (r (105) = 0.49, p<.01) and experience of work flow predicts the flourishing among employees. 2021 Ecological Society of India. All rights reserved. -
Role of energy sources in promotion of sustainable development: moderating implications of globalisation
This study empirically investigates the impact of renewable and non-renewable energy generation on sustainable development for a balancedpanel of 68 developed and developing economies from 1990 to 2019. This is done to scrutinise the intricate interplay between energy sources and sustainable development outcomes at the global level. The estimated models also control for the effects of globalisation, urbanisation, and government expenditure. The Westerlund cointegration establishes a significant long-run relationship between the variables under consideration. In this regard, the two-step dynamic system-generalised moment method (system GMM) demonstrates a positive impact of renewable energy, globalisation, and government expenditure on sustainable development. In contrast, non-renewable energy and urbanisation exert detrimental influences on it. However, both the energy sources demonstrate an amplified positive impact on sustainable development under the moderating influence of globalisation. The Feasible Generalised Least Squares estimation also confirms the long-run reliability of these baseline findings. Furthermore, Granger based non-causality test establishes a significant causal relationship between the variables under consideration. Potential policy suggestions for promoting the sustainable development are also discussed. The Author(s), under exclusive licence to Springer Nature B.V. 2024.