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Experimental and Theoretical Investigation of 3-[(2-chlorophenyl)diazenyl]pyridine-2,6-diamine as Optical Limiter
Azobenzenes undergo reversible trans-cis photoisomerization and have been extensively studied as photoresponsive material. In contrast, azopyridines have garnered relatively less attention despite their similar photochemistry. When compared to azobenzene, azopyridines offer more opportunities for material design through hydrogen bonding and coordination chemistry. Here, we report the isomerization for 3-[(2-chlorophenyl)diazenyl]pyridine-2,6-diamine (1od) through an integrative experimental and computational study. Notably, the energy barrier of 1od was significantly lower than that of previously reported azobenzenes. Moreover, we investigated and elucidated the photoisomerization pathway. 1od exhibited high nonlinear absorption, with a nonlinear absorption coefficient (?eff) of 1.31 (Formula presented.) 10?9 m W?1, as determined by Z-scan measurements. The results indicate that 1od has potential applications in optical limiters, which are used to fabricate protective eyewear and safeguard optical sensors from damage. 2023 Wiley-VCH GmbH. -
Spectroscopic and TDDFT investigation of highly selective fluoride sensors by substituted acyl hydrazones
In this work, we report the synthesis of two receptors for fluoride ions based on acyl hydrazone, such as N?-[(1Z)-1-(4-fluorophenyl)ethylidene]benzohydrazide (R1) and N?-[(1Z)-1-(2-hydroxyphenyl)ethylidene]benzohydrazide (R2). The receptors R1 and R2 were synthesized from the corresponding ketones and benzoic acid hydrazide and characterized spectroscopically by UVvisible, IR and 1HNMR techniques. The response of R1 and R2 towards different anions was studied colourimetrically in acetonitrile. The receptors exhibited a specific response towards fluoride ions. Further studies of 1:1 composition of receptors, R1/R2:fluoride ions by different spectroscopic techniques such as UVVisible, IR and 1HNMR spectroscopy indicated the participation of -NH proton of the receptors in the sensing action through the hydrogen bonding. To understand the mechanism, Time-Dependent Density Functional Theory (TD-DFT) studies were done using the CAM-B3LYP/6311G++ (3df,2p) with Grimme's D3BJ empirical dispersion basis set. The studies supported the role of hydrogen bonding interaction of -NH and-OH protons of the receptors with the fluoride ions. 2020 Elsevier B.V. -
Unveiling the therapeutic potential of azopyridine derivatives for trypsin inhibition: a DFT and In-Vitro approach
Heterocyclic azo derivatives have emerged as promising scaffolds for drug development. This study focused on the synthesis, computational analysis, and biological evaluation of a series of azopyridine derivatives (1a, 1d, 1 g, 1 h, 1 m, 1p, and 1s) as potential trypsin inhibitors. Density Functional Theory calculations indicated that derivative 1 h exhibited the lowest HOMO-LUMO energy gap 3.167 eV and was characterised as a soft molecule, suggesting strong binding capabilities. Molecular docking studies confirmed that 1 h binds favourably to the active site of trypsin with a glide score of ?6.581 kcal/mol and binding energy of ?29.95 kcal/mol. Along with docking studies, the stability of the trypsin-1 h complex was further analyzed using molecular dynamic simulations at 200 ns. The results showed that the ligand molecule 1 h bound strongly at the active site of trypsin. In-vitro enzyme assays determined the IC50 value of the molecule as 100 M, demonstrating enhanced potency. These results indicate that AzPy derivatives, particularly 1 h, hold considerable promise as therapeutic agents for inflammatory disorders and cancer, paving the way for further exploration in drug development and targeted therapies. Further research is warranted to explore 1hs efficacy, safety, and structure-activity relationships. Highlights: DFT studies were used to classify molecules based on their softness and hardness. Molecular docking, simulation, and in-vitro studies have identified potential anti-trypsin activity of candidate molecules. Experimental and computational calculations were in close agreement. 2024 Informa UK Limited, trading as Taylor & Francis Group. -
Diazo-pyrazole analogues as photosensitizers in dye sensitised solar cells: Tuning for a better photovoltaic efficiency using a new modelling strategy using experimental and computational data
The designing of a dye sensitised solar cell (DSSC) is one of the frontiers in harvesting solar energy as it provides an alternative to economic photovoltaic devices with increased efficiency. In this manuscript, we report a new methodology using experimental and theoretical data for the evaluation of the photosensitiser activity of organic dyes using theoretical simulations and experimental cell efficiency data. As a representative example, we designed a series of 54 novel pyrazole derivatives which are subjected to TD-DFT simulations (CAM-B3LYP/6-311G++ (2d, p)) and photovoltaic modelling. Data from computational simulations, as well as known experimental cells, are used for the calculation of photovoltaic efficiency. We selected pyrazole derivatives because of its proven use in DSSC as an effective dopant in a blended polymer electrolyte in nanocrystalline DSSC. Fine-tuning with the effect of substitution and with the ?spacers at the ortho, meta and para positions for -OCH3, -OH, -CHO, -NO2 respectively were done. Enhanced efficiency of 7.439% was observed as compared to the standard cell of efficiency of 5.530%. An increase in efficiency was not observed with the effect of ?spacers. The newly designed dyes demonstrate desirable energetic and spectroscopic parameter that can lead to efficient metal-free organic dye sensitiser for DSSC's. The main advantage of this strategy is the incorporation of both simulated and experimental data. It will reduce the possible errors from the simulations and also, helps in performing time-consuming experimental studies. 2020 Walter de Gruyter GmbH, Berlin/Boston. -
Photoisomerization Dynamics of 2-[(E)-(4-fluorophenyl)diazenyl]-1 H -imidazole: A Theoretical and Experimental Insight
This study investigates the photoresponsive behavior of substituted azobenzenes with a specific focus on their nonlinear optical response. This study suggests that azoimidazole substitution is a better alternative to azobenzene derivatives for nonlinear optical responses. The synthesis, characterization, photophysical property and isomerization pathway of 2-[(E)-(4-fluorophenyl)diazenyl]-1H-imidazole (E-2g) are presented as an optical limiter through a comprehensive blend of experimental and theoretical approaches. Notably, E-2g exhibited a lower energy barrier than reported azobenzenes. The trans-to-cis photostationary state was reached in 75 min, while the cis-to-trans state was achieved in 60 min at 354 nm. The study further explores the photoisomerization pathway of E-2g, highlighting its nonlinear absorption, which has a nonlinear absorption coefficient (?eff) of 8.8 10-11 m/W at 20 ?J, as determined by Z-scan measurements. The results suggest that E-2g exhibits significant nonlinear absorption characteristics, which helps in applications requiring protection from intense light sources. 2024 World Scientific Publishing Company. -
Detection of strangers based on dogs sound
Nowadays, people having a pet at home are increasing. Usually, dog is the favorite pet animal for most of the people in the world. Dogs are more capable of identifying strangers in the surroundings than humans. The proposed work identifies the strangers based on the barking sound of the dog. In this anticipated work, multiple features are extracted from the dogs barking sound using Fast Fourier Transform and Statistical based methods. The classification is done using Nae Bayes classifier. The dataset contains 770 barking audio files of 8 dogs. Whenever known and unknown person comes home, the sounds of the dogs are recorded. The classification result for identifying the stranger is 79.1094%. BEIESP. -
Study of nanofluid flow in a stationary cone-disk system with temperature-dependent viscosity and thermal conductivity
The substantial temperature gradient experienced by systems operating at relatively high temperatures significantly impacts the transport characteristics of fluids. Hence, considering temperature-dependent fluid properties is critical for obtaining realistic prediction of fluid behavior and optimizing system performance. The current study focuses on the flow of nanofluids in a stationary cone-disk system (SCDS), taking into account temperature-dependent thermal conductivity and viscosity. The influence of Brownian motion, thermophoresis, and Rosseland radiative flux on the heat transport features are also examined. The Reynolds model for viscosity and Chiam's model for thermal conductivity are employed. The Navier-Stokes equation, the energy equation, the incompressibility condition, and the continuity equation for nanoparticles constitute the governing system. The Lie-group transformations lead the self-similar ordinary differential equations, which are then solved numerically. Multi-variate non-linear regression models for the rate of heat and mass transfers on the disk surface were developed. Our study reveals a notable decrease in the rate of heat and mass transfer when pre-swirl exists in the flow. The significant influence of nanofluid slip mechanisms on the effective temperature and nanofluid volume fraction (NVF) within the system is highlighted. Furthermore, the variable viscosity property enhances the temperature and NVF of the SCDS. 2024 Author(s). -
Study of hybrid nanofluid flow in a stationary cone-disk system with temperature-dependent fluid properties
Cone-disk systems find frequent use such as conical diffusers, medical devices, various rheometric, and viscosimetry applications. In this study, we investigate the three-dimensional flow of a water-based Ag-MgO hybrid nanofluid in a static cone-disk system while considering temperature-dependent fluid properties. How the variable fluid properties affect the dynamics and heat transfer features is studied by Reynoldss linearized model for variable viscosity and Chiams model for variable thermal conductivity. The single-phase nanofluid model is utilized to describe convective heat transfer in hybrid nanofluids, incorporating the experimental data. This model is developed as a coupled system of convective-diffusion equations, encompassing the conservation of momentum and the conservation of thermal energy, in conjunction with an incompressibility condition. A self-similar model is developed by the Lie-group scaling transformations, and the subsequent self-similar equations are then solved numerically. The influence of variable fluid parameters on both swirling and non-swirling flow cases is analyzed. Additionally, the Nusselt number for the disk surface is calculated. It is found that an increase in the temperature-dependent viscosity parameter enhances heat transfer characteristics in the static cone-disk system, while the thermal conductivity parameter has the opposite effect. The Author(s) 2024. -
Study of nanofluid flow and heat transfer in a stationary cone-disk system
Rheometric, viscosimetric, bio-medical, and several other pharmaceutical machineries utilize the structural advantages provided by the geometry of a stationary conical diffuser. The problem of the Buongiorno nanofluid flow in the conical gap of a stationary cone-disk system for isothermal boundaries is studied. The governing system, comprising the incompressibility condition, NavierStokes equation, energy conservation equation, and conservation of Nanoparticle Volume Fraction (NVF) equation, is analyzed. The Lie-group theory has been used to derive a self-similar model. Solutions of the self-similar equations were computed numerically, and the expressions for the Nusselt number and Sherwood number are obtained. The parametric investigation reveals that the heat and mass transfer rate subside significantly when pre-swirl is introduced to the flow. Furthermore, the nanofluid slip mechanisms enhance the effective temperature of the system. 2023 Elsevier Ltd -
Architecture of FTO/n-CdS/p-SnSe1-xOx/Au Heterojunction Thin Film Diodes by Thermal Evaporation
In this report, FTO/n-CdS/p-SnSe1-xOx/Au heterojunction diodes were fabricated using a homemade precursor followed by dry milling with a facile thermal evaporation method under oxygen atmosphere (10? 2mbar) for the first time. The chemical purity (45.35:45.07:9.58 at.%) and microstructure of the deposited films and device were characterized by energy dispersive x-ray analysis, x-ray photoelectron spectroscopy, and scanning electron microscopy. The crystallographic parameters, a = 11.512 b = 4.163and c = 4.452 with orthorhombic crystal structure and monophase nature were analyzed by powder x-ray diffraction. Raman spectroscopy revealed the vibrational modes, and UVVis-NIR spectroscopy was used to study the direct nature of optical absorption with a band gap of 1.14eV. The currentvoltage (I-V) characteristics of the semiconductor diode were measured in room temperature (25C) and revealed rectifying properties and the cut-off voltage for the device, 0.57V. The obtained results highlight that the use of a p-SnSe1-xOx (SSO) layer as an interface between n-CdS/Au diodes exhibits excellent rectifying behavior and enhanced diode performance. Therefore, the p-SSO layer is a suitable material for heterojuction diodes and optoelectronic switches. Graphical Abstract: [Figure not available: see fulltext.]. 2022, The Minerals, Metals & Materials Society. -
Adsorptive removal of Cr (VI) using mesoporous iron-aluminum oxyhydroxide-polyvinyl alcohol self-supporting film: Kinetics, optimization studies and mechanism
Over the past decades, the disposal of heavy metals like Cr(VI) from industries had an adverse effect on the environment, thus making it a topic of particular interest. In this context, mesoporous Aluminum oxyhydroxide-polyvinyl alcohol self-supporting films were synthesized, and different transition metals (V, Fe, Co, Ni and Cu) were incorporated by an eco-friendly route, and their adsorptive capacity towards Cr (VI) was studied. The composite mesoporous film with iron, aluminum oxyhydroxide and PVA was more efficient adsorbent than other transition metal incorporated aluminum oxyhydroxide films. The surface and chemical properties of the film were confirmed by pXRD, FTIR, Raman Spectra, BET-Surface area, BJH, SEM and Optical Profilometry. Furthermore, the effect of different parameters that impact the adsorption capacity towards Cr (VI) is discussed, including adsorbent load, contact time, solution pH, temperature, and initial concentration. A detailed investigation of the film before and after the adsorption of Cr (VI) using different characterization techniques is investigated in detail. The kinetic studies and adsorption isotherms are studied, and a suitable mechanism has been proposed for Cr (VI) removal. The synthesized films possess potential advantages like cost-effectiveness, eco-friendly nature, reusability, and higher removal efficiency towards the removal of Cr (VI) from an aqueous solution. 2023 Elsevier Ltd -
Women empowerment through community-based organisations in rural Karnataka
Women empowerment is an active multidimensional process to enable women to realize their identity and power in all spheres of life. Self Help Groups (SHGs) have played a significant role in women's empowerment. Through the SHGs, the dreams and desires of women came into reality. The current study examines women's empowerment through community-based organisations in rural Karnataka (Hoskote, Jamkhandi and Kolar). The chapter aims to determine the impact of SHGs on rural women's lives and whether it contributes to women's empowerment. The chapter follows a mixed-method research design. Thirty well-performing SHGs from three Centre for Social Action (CSA) project sites in rural Karnataka, namely Hoskote, Jamkhandi and Kolar, were considered for this chapter. A simple random sampling technique was used. Ten members from each SHG were selected, and three hundred SHG women samples were recruited. Responses from the samples were collected using pre-designed questionnaires. The results state that there is a well-evident improvement in women's economic, social, familial and political status after joining the SHG. The chapter concludes that SHG has caused significant change and development in women's socio-economic, familial and political life in rural Karnataka. 2024 Nova Science Publishers, Inc. -
A study on Organizational Commitment in relation to Job Involvement in the Information Technology Industry
The research is entitled A Study on Organizational Commitment in relation to Job Involvement in the Information Technology Industry. Both Job Involvement and Organizational Commitment are areas of much interest to academicians, researchers, HR practitioners and the industry in its entirety. The last few decades has seen an increased interest in the study of both Organizational Commitment and Job Involvement by academicians and practitioners in a variety of work settings in the hope that it improves job performance and organizational effectiveness, and reduces tardiness, absenteeism and turnover. Organizations are realizing that it is critical to not just attract the right kind of talent but also ensure the retention of their key talent by addressing the problem of retention. Hence the increased focus on areas such as Job Satisfaction, Job Involvement, Organizational Commitment, Human Resource Development, Psychological Contract, Organizational Citizenship Behaviour or OCB, Organizational Development or OD initiatives, Retention strategies, Employee Engagement, etc. Each of these HR activities play a key role in achieving an organization??s strategy, goals, vision and mission. Both Job Involvement and Organizational Commitment have been studied because they are believed to affect and impact organizational performance and effectiveness in addition to clearly predicting other important variables such as absenteeism, turnover, organizational citizenship behaviour, etc. Several studies have indicated organizational commitment to be a better predictor of turnover than job satisfaction. This study, however, is intended to examine the impact of Job Involvement on Organizational Commitment specifically in the IT industry, and also understand the influence of several personal, situational, and organizational characteristics pertaining to Job Involvement on Commitment. The sample considered was 250 IT workers across various levels (right from industry freshers with no work experience whatsoever to Senior Managers with 12 to 15 years of IT experience) and functions in various IT organizations in Bangalore, India. It involved all employees working in IT organizations, including employees in functions such as HR & Training, Administration, Quality, Marketing/Sales and Finance in these organizations. The tools used for the study were (a) Organizational Commitment Questionnaire or OCQ developed by Meyer, Allen and Smith (1993); the internal reliability coefficient (Cronbach??s alpha) was found to be 0.95; and (b) the Lodahl and Kejner Job Involvement Scale (1965); Cronbach??s alpha for the 20-item Job Involvement scale was 0.79. Some of the key findings of this study were: 1. There is a significant relation between Job Involvement and Organizational Commitment of employees in the Indian IT industry 2. There is a significant influence of Job Involvement on Organizational Commitment of employees in the IT industry 3. There is a significant influence of Job Involvement on Affective Commitment of employees in the IT Industry. 4. There is a significant influence of Job Involvement on Normative Commitment of employees in the IT industry. 5. There is a significant influence of Job Involvement on Continuance Commitment of employees in the Indian IT industry 6. There is a significant difference between Organizational Commitment across demographics in the Indian IT industry. The researcher has also discussed the limitations and future research areas on the variables of this study. -
Further Results on the 3-Consecutive Vertex Coloring Number of Certain Graphs
A 3-consecutive vertex coloring is an assignment of colors on vertices of a graph G such that for any 3-consecutive vertices a, b and c, the color of b is the same as the color of a or c. ? 3c(G) denotes the maximum number of colors that can be used to 3-consecutive vertex color a graph G. The main aim of this article is to give the value of ? 3c(G) for some particular types of graphs, which includes: necklace graphs; the Cartesian product of two paths, a cycle and a path, and two cycles; the corona product of a path and a clique; Mobius Ladder graphs; the 3rd edge line graph; triangular snake graphs, double triangular snake graphs, triple triangular snake graphs, quadrilateral snake graphs and the alternative versions of them; Hanoi graphs; Sun graphs; Barbel graphs; the n-pan graph. The objective of this article is to explore some important results on ? 3c(G). 2024 The Authors. -
The silent struggle of teachers
By all means, let the child bloom. But do not forget to water the roots, writes John J Kennedy -
IoT-Enabled Analysis of COVID Data: Unveiling Insights from Temperature, Pulse Rate, and Oxygen Measurements
The COVID-19 pandemic has forced unparalleled transformation on healthcare systems around the world, demanding new and improved approaches for effective monitoring and diagnosis. In this context, we present a study titled IoT-Enabled Analysis of COVID Data: Unveiling Insights from Temperature, Pulse Rate, and Oxygen Measurements. The global impact of COVID-19, with millions of confirmed cases and fatalities, underscores the urgency of finding efficient monitoring solutions. To address this crisis, IoT-Enabled Health Monitoring Systems have emerged as a promising tool for remote patient monitoring and infection risk reduction. These systems leverage sensors to collect real-time data on the temperature, pulse rate, and oxygen saturation levels of the subject. The integration of a mobile application enables immediate access to this critical health information. In this study, we explore the use of IoT systems, which have demonstrated accuracy comparable to other devices on the market. By leveraging these technologies, we aim to provide healthcare professionals with valuable insights into patients health status, aiding in early detection, monitoring, and timely intervention. Our research contributes to the efforts to battle the COVID-19 pandemic by highlighting the potential of IoT-enabled monitoring systems in enhancing healthcare delivery, reducing infection risks, and ultimately saving lives. 2024 Scrivener Publishing LLC. -
Integrating AI Tools into HRM to Promote Green HRM Practices
The image of Human Resource Management (HRM) is undergoing a drastic transformation. The conventional methods are evolving due to the emergence of technology, especially with the integration of Artificial Intelligence (AI) and data analytics into the HR processes. With the rapidly changing concept of the overall growth of an organization, AI is becoming a vital stimulant for sustainable growth. AI-powered tools promote data-driven decision-making for talent acquisition, performance management, workforce training and development, optimization of energy consumption and waste reduction. Green HRM aligns these efforts by integrating sustainability considerations into talent management strategies, nurturing employees eco-engagement, and promoting environmentally responsible practices within the workforce. This research paper aims to explore the synergies between AI tools and Green HRM practices, investigating how the integration of AI technologies into HR processes can contribute to the promotion of environmental sustainability. By examining real-world case studies, this study aims to investigate the potential of AI-powered solutions in shaping the future of HRM through the lens of sustainability. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024. -
Quantitative X-ray and Spectroscopic Analysis of Nanocrystalline and Amorphous Carbon Materials
Carbon and its various allotropic forms is a blooming and extensively investigated field for the past few decades. The revolution which started with the discovery of fullerenes in 1985 continues with the newly discovered wonder material graphene and has never failed to amass the interest of scientific community. After all these years it still stays as a hot topic of research. This is primarily due to their unique physical and chemical properties which makes them suitable for a whole host of applications ranging from thin film technology to nano-medicine. But, the production cost of these novel materials is an issue which shadows its glory and hence it is essential to find out efficient and cost effective sources and production methods for these materials. Graphene oxide has attracted much interest because of its low cost, easy access and unique ability to get converted into graphene. Graphene oxide is basically, a graphene sheet which consists of either carboxyl or hydroxyl groups. Foreseeing the upcoming era of carbon nanomaterials on account of their revolutionary applications and the ever increasing demand for economical and viable sources, we have identified and explored the structural parameters of an efficient and cost effective precursor of the same. In the present investigation, wood charcoal and coconut shell charcoal, which is a superior source of activated carbon, is produced by a slow thermal decomposition method in a limited supply of oxygen. It is an impure form of carbon- is a black residue composed mainly of carbon, ash and char. Wood charcoal is transformed into Graphite oxide (GO) by a modified Hummers method. Spectroscopic analysis of the samples is carried out by various techniques such as X-ray diffraction (XRD), Raman Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), X-ray Photoelectron Spectroscopy (XPS), UV-Vis spectroscopy and Scanning Electron Microscopy (SEM). The various structural parameters are calculated from XRD and Raman data. -
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PICTURE PROCESSING ON ISOMETRIC FUZZY REGULAR ARRAY LANGUAGES
Isometric array grammar is one of the simplest model to generate picture languages, since both sides of its production rule have the same shape. In this paper, we have introduced isometric fuzzy regular array grammars to generate isometric fuzzy regular array languages and discussed its closure properties. Also, the relation between isometric fuzzy regular array grammar and boustrophedon fuzzy finite automata has been discussed. Moreover, we study the relation between two dimensional fuzzy regular grammars with returning fuzzy finite automata and boustrophedon fuzzy finite automata. Further, the hierarchy results of these three classes of languages have been discussed. 2024 KSCAM.