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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. -
The role of meditation and mindfulness in the management of polycystic ovary syndrome: a scoping review
Polycystic Ovary Syndrome (PCOS) presents multifaceted challenges affecting womens reproductive, metabolic, and psychological systems, consequently impacting their psychological and emotional well-being. The utilization of meditation and mindfulness interventions (MMIs) is found to be increasing for the management of PCOS. This scoping review systematically explored the current literature to identify the type and application of MMIs for PCOS management. A systematic search of literature was conducted using CINAHL, PsycINFO, Scopus, MEDLINE, and PubMed databases for identifying studies conducted on the usage of MMIs in women diagnosed with PCOS, irrespective of age. The comprehensive search identified 14 trials (comprising 17 citations) meeting inclusion criteria, involving 723 participants across various age groups. Among these, nine were randomized controlled trials (RCTs), while the remaining comprised non-RCTs. Several types of MMIs, including Rajayoga of Brahmakumaris, Yoga Nidra, OM cyclic meditation, unspecified forms of meditation, mindfulness-based stress reduction programs, mindful yoga, and mindfulness-based activities, were used. Outcomes were predominantly assessed in psychological domains (n=11), followed by anthropometric (n=9), quality of life (n=7), and metabolic metrics (n=7). The review findings suggest the integration of meditation with conventional treatment modalities. Preliminary data indicate that MMIs have the potential to improve psychosocial well-being and quality of life among PCOS-affected women. However, adequately powered studies with extended follow-up periods are required to investigate the mechanisms and therapeutic efficacy of MMIs, particularly concerning reproductive outcomes and weight management. Furthermore, diligent monitoring and reporting of adverse events and adherence are essential for a comprehensive understanding of MMI utilization in PCOS management. Copyright 2024 Rao, Pena, James, Phadke, Grover, Blendis, Choudhary and Kampegowda. -
Estimation of secured wireless sensor networks and its significant observation for improving energy efficiency using cross- learning algorithms
Wireless sensor networks (WSNs) have as of late been created as a stage for various significant observation and control applications. WSNs are continuously utilized in different applications, for example, therapeutic, military, and mechanical segments. Since the WSN is helpless against assaults, refined security administrations are required for verifying the information correspondence between hubs. Because of the asset limitations, the symmetric key foundation is considered as the ideal worldview for verifying the key trade in WSN. The sensor hubs in the WSN course gathered data to the base station. Despite the fact that the specially appointed system is adaptable with the variable foundation, they are exposed to different security dangers. Grouping is a successful way to deal with vitality productivity in the system. In bunching, information accumulation is utilized to diminish the measure of information that streams in the system. 2021 by IGI Global. -
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 fast survey on recent developments in designing colorimetric and fluorescent sensors for the selective detection of essential amino acids
Owing to the biological significance of various amino acids, developing accurate and cost-effective sensing techniques for the selective detection of amino acids has recently attracted growing interest. This review discusses the recent advancements of chemosensors in the selective detection of only essential amino acids out of a total of twenty amino acids, which have been applied in chemosensing research, and the mechanism of their action. The focus is directed towards the detection of the most important essential amino acids, like leucine, threonine, lysine, histidine, tryptophan and methionine, since isoleucine and valine are yet to be explored in regard to chemosensing. According to their chemical and fluorescence properties, different sensing techniques, such as the reaction-based approach, DNA-based sensors, nanoparticle formation, coordination ligand binding, host-guest chemistry, the fluorescence indicator displacement (FID) approach, electrochemical sensors, carbon dot-based sensors, MOF-based sensors and metal-based techniques, have been described. 2023 The Royal Society of Chemistry. -
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. -
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 -
Role of Constructivism Developing Metacognitive Abilities Among Secondary School Students
Research Tracks, Vol-1 (1), pp. 125-128. ISSN-2347-4637 -
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. -
Fabrication of disposable sensor strips for point-of-care testing of environmental pollutants
Biosensors are potentially used in detection of trace amount of environmental pollutants. Nanostructured materials are being widely explored for its application in the field of biosensors for monitoring environmental pollutants. Advances in biosensor technology with the use of micro-/nanomaterials can detect and analyze living and chemical matter with high specificity, which is relatively fast, sensitive, accurate, and inexpensive for the determination of chemical and biological contaminants. Recent finding shows that carbon nanotubes (CNTs) and nanomaterial-based biosensors utilizing the electrochemical and optical properties are being used for the analysis of contaminants at an incredible sensitivity and accuracy. In this chapter, the application of CNT-based biosensors and the fabrication of paper-based sensors in monitoring hazardous environmental pollutants are discussed. 2022 Elsevier Inc. All rights reserved. -
Change in Outlook of Indian Industrial OEMs Towards IIoT Adoption During COVID-19
Industrial Internet of Things (IIoT) is witnessing a steady increase in adoption by infrastructure and process industries. Industrial equipment manufacturers are one of the key stakeholders in this digitalization journey. The adoption of IIoT by the equipment manufacturers has been slower due to various valid reasons. The present pandemic COVID-19 created disruption in the factory operations in many parts of the world. This consequence has been hard on the manufacturing industry including the equipment manufacturers, and many of their strategic projects are slowing down or derailed. In India, a strict lockdown of three weeks which was later extended for another seven weeks was by far the longest lockdown effecting the industry and the equipment manufacturers. This study probes the impact of COVID-19 on the mindset of original equipment manufacturers (OEMs) towards adoption of IIoT. 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. -
Efficiency Analysis of Modified Sepic Converter for Renewable Energy Applications
A boosting module and a traditional SEPIC (single ended primary inductance converter) are combined to create the suggested circuit. As a result, the converter gains from the SEPIC convertera's many benefits. Also, the converter that is being presented is appropriate for renewable energy sources due to its high voltage gain and continuous input current. In comparison to a traditional SEPIC with a single-controlled switch, it offers a higher voltage gain. The voltage gains of the converter that has been suggested is closely related to that of the converter that was recently developed. This converter was constructed on the foundation of the conventional converter, as well as the conventional DC-to-DC converter. One of the most important characteristics of a projected converter is that it is equipped with a single controlled device and has the capability to increase voltage gain without the utilisation of a coupled inductor structure or transformer. The non-idealities of the semiconductor devices and passive components have been taken into consideration in the analysis of voltage gain in continuous current mode (CCM). The conventional SEPIC converter can be modified by incorporating capacitors and diodes. The experimental results indicate that this converter can amplify the output voltage by approximately 10 times and has an efficiency of around 97%. The Authors, published by EDP Sciences, 2024. -
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. -
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 -
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. -
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. -
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 -
An outlook on zero-dimensional nanocarbons as components of DSSC
Solar energy is an abundant source of energy, and harnessing the suns radiation with an efficient solar cell can be a promising technology for a limitless supply of sustainable energy. The amount of solar power that reaches the earth is beyond the worlds energy consumption. But, the main cause for minimal usage of the suns energy is the complicated technology, restricted band gap, high-temperature instability, and high cost of production. Likewise, the usage of space and infrastructure required for the installation of solar cells is yet another reason for limited usage. Upon comparing the emerging photovoltaics, DSSC (dye-sensitized solar cells) can be a solution for the drawbacks faced by the older generation solar cells which has greater future scope as an energy harvester. Rapid technological growth over the years, usage of affordable materials, and capability of working efficiently in low lighting conditions make DSSC a commercially viable and potent solar energy harvester. Furthermore, its efficiency can be improved with the inclusion of low-dimensional nanocarbons in various components of DSSC. Therefore, this review describes the mechanisms of improving the performance of zero-dimensional nanocarbons and their application in components of DSSC alternative to conventional materials. The significant impact of surface functionalization of low-dimensional nanocarbon on the performance of dye-sensitized solar cells is also discussed. Graphical abstract: (Figure presented.) The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2022. Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. -
Finite Element Analysis of Hybrid Skin Sandwich Composite
Sandwich structured composite is a particular classification in composite materials. This type of structure has been mainly used in recent studies because of its high specific strength, low density, and stiffness. It is increasingly more commonly employed in structural designs due to its features and performance. The sandwich composites used in this investigation are made of aluminium alloys and areca fibre. The sandwich composites face sheet comes in a variety of thicknesses. The adhesive skin layer is also varied to investigate the effect of using natural fibre. The sandwich composite is subjected to 3 point bend test. The modal analysis is investigated using the finite element method. The 3D model of sandwich composites is modelled using solid works 2020. Using Altair Hyper Works, the boundary conditions and meshing is carried out. ANSYS Mechanical APDL is used to analyse the sandwich composites. This investigation analyses the behaviour of composite sandwich beams. 2022, Books and Journals Private Ltd.. All rights reserved. -
ArcGAN: Generative Adversarial Networks for 3D Architectural Image Generation
Due to advancements in infrastructural modulations, architectural design is one of the most peculiar and tedious processes. As the technology evolves to the next phase, using some latest techniques like generative adversarial networks, creating a hybrid architectural design from old and new models is possible with maximum accuracy. Training the model with appropriate samples makes it evident that the designing phase will be simple for even a layman by including proper parameters such as material description, structural engineering, etc. This research paper suggests a hybrid model for an architectural design using generative adversarial networks. For example, merging Romes architectural style with Italys will accurately and precisely recover the pixel-level structure of 3D forms without needing a 2D viewpoint or 3D annotations from a real 2D-generated image. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.