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Furaldehyde-based magnetic supported palladium nanoparticles as an efficient heterogeneous catalyst for Mizoroki-Heck cross-coupling reaction
A novel palladium functionalised magnetic nanocatalyst (Fe3O4@SiO2-FA-Pd) was prepared using silica-coated iron oxide and furaldehyde Schiff base as a supported material. FT-IR, VSM, TEM, FESEM, XPS, EDAX and TGA were used to analyse the morphological structure and chemical composition of Fe3O4@SiO2-FA-Pd NPs. Thus, the prepared Fe3O4@SiO2-FA-Pd NPs as a magnetic nanocatalyst were used in the Mizoroki-Heck reaction of arylbromide and terminal alkenes, exhibiting effective catalysis with good yields. The magnetic nanocatalyst can be reused up to 6 times without significantly losing catalytic activity and is easily separable from the reaction mixture. This new catalytic system has significant and potentially useful applications in the pharmaceutical industry. 2024 The Royal Society of Chemistry. -
Palladium immobilized on guanidine functionalized magnetic nanoparticles: a highly effective and recoverable catalyst for ultrasound aided Suzuki-Miyaura cross-coupling reactions
We designed and prepared a palladium catalyst that can be magnetically recyclable by anchoring guanidine moiety on the surface of Fe3O4 nanoparticles, named Fe3O4@SiO2-TCT-Gua-Pd. It was established to be a potent catalyst for the Suzuki-Miyaura cross-coupling reaction (SMCR) in the EtOH/H2O system under ultrasonic conditions. FT-IR spectroscopy, field-emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) microanalysis, vibration sample magnetometry (VSM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and inductively coupled plasma atomic emission spectrometry (ICP-AES) analyses were used to characterize the structure of the Fe3O4@SiO2-TCT-Gua-Pd nanoctalyst. The Fe3O4@SiO2-TCT-Gua-Pd catalyst produced favorable coupled products with excellent yields and was harmonious with various aryl halides and aryl boronic acids. The stability, low palladium leaching, and heterogeneous nature of the nanocatalyst were confirmed by a hot-filtration test. The palladium nanocatalyst could be easily recovered by magnetic field separation and recycled at least 6 times in a row without noticeable loss in its catalytic activity. 2023 The Royal Society of Chemistry. -
Nano-architectured polypyrrole based magnetic nanocatalyst for the N- arylation of imidazoles and fused imidazoles
A new magnetically recoverable polypyrrole supported copper based nanocatalyst was synthesized, characterized with various analytical techniques like Fourier-transform infrared spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray analysis (EDX), High Resolution Transmission Electron Microscopy (HRTEM), Thermogravimetric analysis (TGA), Vibrating Sample Magnetometry (VSM), and Inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis. The loading of copper on the surface of the catalyst was found to be 4.23 wt%. The application of the synthesized nanocatalyst was checked for the N-arylation of imidazoles. Excellent catalytic performance was obtained with easy recoverability and reusability upto six cycles. The current green protocol makes it environmentally beneficial for scale-up industries. 2025 Elsevier B.V. -
Photovoltaic Structures Using Thermally Evaporated SnS and CDS Thin Films
Thin Solid Films, Vol-545, pp. 543-547. ISSN-0040-6090 -
Optical and electrical properties of SnS semiconductor crystals grown by physical vapor deposition technique
Tin sulfide (SnS) is a material of interest for use as an absorber in low cost solar cells. Single crystals of SnS were grown by the physical vapor deposition technique. The grown crystals were characterized to evaluate the composition, structure, morphology, electrical and optical properties using appropriate techniques. The composition analysis indicated that the crystals were nearly stoichiometric with Sn-to-S atomic percent ratio of 1.02. Study of their morphology revealed the layered type growth mechanism with low surface roughness. The grown crystals had orthorhombic structure with (0 4 0) orientation. They exhibited an indirect optical band gap of 1.06 eV and direct band gap of 1.21 eV with high absorption coefficient (up to 103 cm-1) above the fundamental absorption edge. The grown crystals were of p-type with an electrical resistivity of 120 ? cm and carrier concentration 1.52015 cm-3. Analysis of optical absorption and diffuse reflectance spectra showed the presence of a wide absorption band in the wavelength range 3001200 nm, which closely matches with a significant part of solar radiation spectrum. The obtained results were discussed to assess the suitability of the SnS crystal for the fabrication of optoelectronic devices. 2011 Elsevier B.V. All rights reserved. -
Vacuum annealed tin sulfide (SnS) thin films for solar cell applications
Thin films of tin sulfide (SnS) were grown on a glass substrate at an optimum temperature of 300 C by thermal evaporation technique. Following the deposition, films were vacuum annealed at different temperatures in the range of 100 to 300 C for 2 h. The effect of annealing temperature (Ta) on the composition, surface morphology, microstructure, optical and electrical properties was investigated. Elemental analysis showed sulfur deficiency of annealed films and the Sn to S atomic percent ratio increased from 1.0 to 1.1. XRD analysis confirmed the orthorhombic crystal structure of the films with (111) preferred orientation and phase purity. Degree of preferred orientation decreased with increase in Ta and the diffraction peaks corresponding to other planes intensified. Increasing the Ta to 300 C led to an increase in crystallite size to 129 nm. Results indicated presence of several crystallites in the grains of as-deposited films. AFM studies revealed the fragmentation of larger grain and the average grain size reduced form 265 nm for as-deposited films to 132.8 nm for the film annealed at 300 C. An apparent shift in absorption edge towards longer wavelengths is observed for films annealed at Ta > 200 C. The optical constant such as optical band gap, extinction coefficient (k), absorption coefficient (?) and refractive index (n) have been evaluated. The optical band gap of SnS thin films varied marginally with the annealing temperature and remained in between 1.331.29 eV. The extinction coefficient of the film annealed at 300 C was enhanced and is found to be 0.85 at 700 nm. At the annealing temperature of 300 C, the SnS films had enhanced electrical properties: the electrical resistivity was 7.8 ? cm, the p-type carrier concentration was up to 2.17 1016 cm?3, and the mobility was about 36.9 cm2V?1s?1. The variation of physical parameters with Ta has been explained by taking into account the crystallite size and the presented values are discussed with relevance to solar cells. 2017 Elsevier B.V. -
Photovoltaic structures using thermally evaporated SnS and CdS thin films
Polycrystalline tin sulfide thin films were prepared by thermal evaporation technique.The films grown at substrate temperature of 300 C had an orthorhombic crystal structure with strong preferred orientation along (111) plane.Electrical resistivity of the deposited films was about 32.5 ? cm with a direct optical band gap of 1.33 eV.Carrier concentration and mobility of charge carriers estimated from the Hall measurement were found to be 6.24 1015 cm- 3 and 30.7 cm2V- 1 s- 1 respectively.Heterojunction solar cells were fabricated in superstrate configuration using thermally evaporated SnS as an absorber layer and CdS, In:CdS as window layer.The resistivity of pure CdS thin film of a thickness of 320 nm was about 1-2 ? cm and was reduced to 40 10- 3 ? cm upon indium doping.The fabricated solar cells were characterized using solar simulator.The solar cells with indium doped CdS window layer showed improved performance as compared to pure CdS window layer.The best device had a conversion efficiency of 0.4% and a fill factor of 33.5%. 2013 Elsevier B.V.All rights reserved. -
Optimising lead qualification through machine learning: A customer data-driven approach
Lead generation is the process of turning an outside person or business into a customer of the business. Traditionally, marketing personnel must conduct significant follow-ups in order to convert even one potential consumer. Converting bad client leads can cause businesses to burn through cash reserves. As a result of this, it is now necessary to develop an automated system that can correctly anticipate whether or not a lead should be explored (converted to a customer or not). In this study, an attempt is made to evaluate historical data for leads produced by other businesses in order to train and validate a machine learning (ML)/deep learning (DL) model and test it against real-world characteristics to categorise them as hot leads (convert to customers) or cold leads (failed leads). This can be achieved by employing ML algorithms, low codeno code libraries, such as PyCaret in Python, and can be used to make predictions regarding probable lead creation, propensity to convert generated leads and optimal actions on the leads by communications teams. Supervised ML algorithms such as logistic regression, decision trees, random forests and other models using a Python library were built to score leads for identifying potential conversions. With good and broad lead-scoring models in place, businesses can optimise their CTI actions on the basis of lead prioritisation and let go of non-prospect leads at the right time to cut costs and enable efficiency. The result of this study reveals that 52 per cent of the sample of 74,779 leads are cold leads and 48 per cent are hot leads that are sales qualified. The leads are qualified using the lead score matrix. This method can aid digital businesses to remove unqualified leads and manage leads better, and therefore improve the quality of the leads sent to clients. This, in turn, will improve conversion rates for individual customers. These increased conversion rates will enhance the business strategy of digital marketing firms. Henry Stewart Publications. -
Protection of Artificial Intelligence Autonomously Generated Works under the Copyright Act, 1957-An Analytical Study
Artificial Intelligence (AI) is not new anymore; it has become a new normal. In the present 3A era (Advanced, automated and autonomous), the Next Rembrandt paintings, Shimons lyrics and songs and Bot Dylans Irish folk songs are the works generated by the AI without any considerable human contribution. In the US, the Copyright Act, 1976 does not protect the works generated independently by the AI without human intervention and thus dropping such works in the public domain immediately after their creation. However, in the UK, the Copyright, Patents and the Designs Act, 1988 under Section 9 (3) attributes copyright to the person by whom the arrangements necessary for the creation of the work are undertaken in case of AI generated works. India has taken a giant leap by considering AI as the joint author along with the human responsible for the creation of work. However, there is not much comprehensive literature available that focuses on the impact of AI being considered as a joint author. This paper aims to create a concrete foundation by emphasising such impact under the Copyright Act, 1957. Furthermore, the paper considers the stance of the US, UK and Australia in protecting AI generated works to suggest measures to the current copyright regime in India. 2023, National Institute of Science Communication and Policy Research. All rights reserved. -
Social Identity of Kodavas Understanding Evolution and Transitions
The Kodavas of Kodagu district in Karnataka have a distinct social structure and follow a set of unique social codes and values peculiar to the community. Various influences have resulted in shifting social identities, which maybe a potential indicator of an identity crisis within the group. The present study follows a Constructivist Grounded Theory approach to inquiry, to arrive at an analytical schema of the process of social identity formation of the Kodavas. The analysis of data collected from forty-one middle and older adults, highlight the core traditional attributes of the Kodava identity, factors contributing to identity transition and its reflection in contemporary times. 2023 Tata Institute of Social Sciences. All rights reserved. -
Yield management in hotel industry: An exploratory study on selected northern states of India: A time series analysis
Asian Journal of Research in Business Economics and Management, Vol. 7, Issue 3, pp. 37-63, ISSN No. 2249-7307. -
Assessment of diversity, abundance, and seasonal variatons of bird species in Bengaluru District, India during COVID-19 lockdown
The study investgates bird populaton dynamics in Bengaluru, India, post-lockdown, focusing on occurrence, seasonal abundance, species diversity, richness, dominance, and evenness. It covers 55 bird species across 52 genera, grouped into 32 families within 13 orders, with a notable peak in winter. Various indices, including Shannon Wiener, Margalefs, Pielous, and Simpsons, reveal signifcant seasonal diferences in bird populaton characteristcs. The Rock Pigeon Columba livia dominates, while the Black-headed Ibis Threskiornis melanocephalus is less prevalent. The study identfes Near Threatened species like Black-headed Ibis and Oriental Darter Anhinga melanogaster, along with Least Concern species per the IUCN Red List. Common species include Rock Pigeon, Large-billed Crow Corvus macrorhynchos, House Crow Corvus splendens, Black Drongo Dicrurus macrocercus, Brown Shrike Lanius cristatus, Common Myna Acridotheres trists, Jungle Myna Acridotheres fuscus, Red-whiskered Bulbul Pycnonotus jocosus, and Streak-throated Swallow Petrochelidon fuvicola. The study aims to inform improved management and conservaton strategies for Bengalurus diverse bird species. Hemanth et al. 2024. Creatve Commons Atributon 4.0 Internatonal License. JoTT allows unrestricted use, reproducton, and distributon of this artcle in any medium by providing adequate credit to the author(s) and the source of publicaton -
Evaluation of mechanical properties of e-glass and coconut fiber reinforced with polyester and epoxy resin matrices
Composite manufacturing is the novel branch of science, which finds its immense applications in various industries such as sporting, automotive, aerospace and marine industries. The superior properties of composites such as stiffness, better mechanical properties, low density and light weight make it a candidate in engineering applications. The need for seeking alternate materials with increased performance in the field of composites revived this research, to prepare fiber reinforced composites by hand layup method using E-glass and coconut fibers with length 5-6 mm. The resin used in the preparation of composites was epoxy and polyester. Fiber reinforced composites were synthesized at 18:82 fiber-resin weight percentages. Samples prepared were tested to evaluate its mechanical and physical properties, such as tensile strength, flexural strength, impact strength, hardness and scanning electron microscope (SEM). Scanning electron microscope analysis revealed the morphological features. E-glass fiber reinforced epoxy composite exhibited better mechanical properties than other composite samples. The cross linking density of monomers of the epoxy resin and addition of the short chopped E-glass fibers enhanced the properties of E-glass epoxy fiber reinforced composite. TJPRC Pvt. Ltd. -
Silenced, Scarred & Shattered: Unmasking the Wounds of Child Sexual Abuse in Select American Memoirs
The research brings to light the marginalized voices of three American women who have written about their sexual abuse in their respective memoirs Roxane Gay, Hunger: A Memoir of my Body (2017), Nikki Dubose, Washed Away: From Darkness to Light (2016) and Neesha Arter Controlled: The worst Night of my Life and its Aftermath (2015). Using these memoirs as primary data and using thematic analysis the study identified three themes which were further classified into different subthemes. Firstly, the research discovered the challenges faced by the survivors in expressing and communicating about sexual abuse due to fear and shame, the survivors do not come forward because of threats, because of rape stereotypes that permeate the society and the fear of what parents and others might think. Secondly, the research explores the various impact of trauma that is caused by sexual abuse which include shame, guilt and self blame, unworthy self, uncontrollable rage, disruption of safety and trust, isolating themselves from everyone, hostility towards body, destructive behaviours which include eating disorder from Anorexia Nervosa to Binge eating disorder, it also includes self harm and substance abuse. Thirdly, the research focuses on the recovery aspect on how the survivors learn to live with the wounds caused by sexual abuse. It focuses on how the survivors came in terms with the abuse, the conflicting feelings of forgiveness and revenge and how they sought redemption through writing their journey. 2025 Sciedu Press. All rights reserved. -
Evaluation of lime juice as potential green corrosion inhibitor using gravimetric and electrochemical studies
Lime, a vibrant fruit of citrus family is known for its antioxidant as well as anti-microbial properties. The constituents of lime juice include organic acids, polyphenols, soluble sugars, vitamins, minerals and amino acids. These details prompted to experiment lime juice as corrosion inhibitor for mild steel in 1 M HCl. The weight loss studies showed that the corrosion inhibition efficiency increased with increase in concentration of the lime juice as well as increase of temperature. The inhibition efficiency reached a maximum of 96% for an immersion period of 24 h. The best fit for the adsorption process obeyed Langmuir isotherm. The negative value of ?Gads showed the spontaneity of the corrosion inhibition process. The corrosion inhibition efficiency of the acidified lime juice was further validated by electrochemical studies namely AC impedance studies and potentiodynamic polarization studies. The surface morphology study was performed used optical profilometer. 2020 Chemical Publishing Co.. All rights reserved. -
3D face recognition based on symbolic FDA using SVM classifier with similarity and dissimilarity distance measure
Human face images are the basis not only for person recognition, but for also identifying other attributes like gender, age, ethnicity, and emotional states of a person. Therefore, face is an important biometric identifier in the law enforcement and human-computer interaction (HCI) systems. The 3D human face recognition is emerging as a significant biometric technology. Research interest into 3D face recognition has increased during recent years due to availability of improved 3D acquisition devices and processing algorithms. A 3D face image is represented by 3D meshes or range images which contain depth information. In this paper, the objective is to propose a new 3D face recognition method based on radon transform and symbolic factorial discriminant analysis using KNN and SVM classifier with similarity and dissimilarity measures, which are applied on 3D facial range images. The experimentation is done using three publicly available databases, namely, Bhosphorus, Texas and CASIA 3D face database. The experimental results demonstrate the effectiveness of the proposed method. 2017 World Scientific Publishing Company. -
3D face recognition based on symobolic FDA using SVM classifier with similarity and dissimilarity distance measure /
International Journal of Pattern Recognition and Artificial Intelligence, 31, Issue 4, ISSN: 1793-6381. -
A short review on environmental impacts and application of iron ore tailings in development of sustainable eco-friendly bricks
Increased mining activity of iron ore has led to the generation of voluminous wastes of various nature, especially during the different stages of its extraction and production. The improper disposal of such waste causes negative impact on the environment. One such waste which is generated during the beneficiation process of iron ore is waste iron ore tailings, which is also termed as IOT. Further, dumping of IOT on open ground creates huge dumping sites. This dumping sites have been a concern to the environment and human population in its close vicinity. Therefore, a need to effectively use IOT has become one of the subjects of interest for many researchers. This article provides a short review of environmental problems caused due to improper disposal of IOT, and also reviews on the reuse methods of IOT in the construction sector, which helps to alleviate the environmental pollution associated with improper disposal of IOT. Furthermore, reuse of IOT in construction sector reduces the exploitation of the virgin materials for production of construction material, and thus reducing depletion of natural resources. Based on the existing literatures and findings it was observed that the use of IOT to develop stable building blocks using unconventional methods showed great potential and improved performance, when compared with conventional materials such as clay fired bricks. 2021 -
Phytochemicals of Nardostachys jatamansi as potential inhibitors of HCV E2 receptor: An in silico study
Hepatitis C virus (HCV) is the causative agent of acute and chronic hepatitis and can lead to liver cirrhosis. High variability in the HCV genome renders vaccine formulation strenuous. Modern pharmaceuticals rely heavily on plant-based compounds for drug production. This study focuses on in-silico screening of phytochemicals derived from an herbal plant, Nardostachys jatamansi, for the treatment of HCV by inhibiting its E2 receptor, which binds to the hepatocytes, enabling viral entry into the liver. Computer-aided drug design utilizes various tools such as molecular docking tools, including AutoDock Vina, Avogadro, PyMol, Discovery Studio Visualizer, LigPlot+, and online tools like SwissADME (Absorption, Delivery, Metabolism and Excretion) for analysis of pharmacokinetics and pharmacodynamics of phytochemicals. Toxicity studies were carried out using pkCSM. 25 bioactive phytochemicals of N. jatamansi were analysed. The analysis was validated by comparing the data of the phytochemicals with an established antiviral drug, ribavirin. This is a novel approach to docking studies, exploring the possibility of medicinal plants as anti-hepatic drugs. Of the 25 compounds, nardosatachysin and ?-gurjunene are the standout performers and are considered potent inhibitors of HCV E2 receptor. The two compounds are recommended for further in vivo and in vitro trials to assess their efficacy in treating HCV infection. 2024 Lalrintluanga Hnamte, et al. -
Purpose-driven leadership and organizational success: a case of higher educational institutions
Purpose: This paper aims to examine the relationships between organizational purpose, leadership practices and sustainable outcomes for universities in emerging economies. We propose that a strong sense of purpose is a fundamental and defining feature in the leadership practices of these institutions, which ultimately contributes to their success. Design/methodology/approach: The authors present a research model that defines the relationships between a sense of purpose, leadership practices, student success outcomes, alumni involvement outcomes and societal reputation outcomes. Over 200 higher education administrators in India participated in the study. Findings: The institutions' sense of purpose directly relates to their leadership engagement practices and their student success outcomes. Student success outcomes are a crucial linkage between leadership engagement practices and alumni involvement outcomes to achieve their societal reputation. Practical implications: As competitiveness intensifies, educational institutions under resource constraints must differentiate their organizational practices. This paper demonstrates how their core purpose and leadership actions result in achieving effective outcomes and overall sustainable societal reputation. Originality/value: There is a significant difference between having an organizational purpose and enacting that purpose through their leadership practices. These results highlight the cascading effect from the institution's fundamental sense of purpose to their leadership practices and the positive outcomes of student success, alumni involvement and societal reputation. 2021, Emerald Publishing Limited.