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Solid state, rapid mechanochemical route for TiO2 coated Schiff-base polymer as adsorbent for the exclusion of hexavalent Cr from water
The removal of hexavalent Cr from water is vital considering its harmful and carcinogenic effects on human health as well as the environment. Effective exclusion of Cr(VI) provides reliable water to consume, impedes bioaccumulation, and mitigates environmental pollution. The present work details the rapid, ecofriendly, solvent-free mechanochemical route for the development of a polymeric Schiff-Base-wrapped TiO2 (SBP@TiO2) nano-adsorbent for the effective removal of Cr(VI) from water. The comprehensive understanding of the structural and chemical characteristics of the newly synthesized materials were examined through Fourier transform infrared (FTIR) spectroscopy, X-Ray Diffraction (XRD), and Scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) spectroscopy. To assess the adsorption capacity, kinetics, and equilibrium of Cr(VI) adsorbate on adsorbent material (TiO2 and SBP@TiO2) and to understand the interplay between the critical parameters and their impact on adsorption, a series of batch adsorption studies were carried out. The adsorption equilibrium data for the Cr(VI) adsorption process fitted well with the Freundlich isotherm model of adsorption and adsorption kinetics disclosed that the data are in excellent agreement with R2 values of 0.98721 for the pseudo-second-order, indicating that the sorption process is by chemisorption. Thermodynamic measurements revealed that the adsorption of Cr(VI) on SBP@TiO2 was spontaneous and endothermic, as corroborated by the ?ve value of ?Go and the +ve value of ?Ho, respectively. It was discovered that the sorption of 10 and 50 ppm of Cr(VI) on SBP@TiO2 was 96% and 75.4% under optimal conditions, respectively. In contrast, the sorption study of Cr(VI) on TiO2 under identical conditions was found to be 49%. The study found that surface functionalization of TiO2 by SBP admirably improved the adsorption capacity, signifying SBP@TiO2 as an efficient Cr(VI) adsorbent. 2024 The Authors -
Efficacy of Psychosocial Care Training Programme for the Staff Working in Old Age Homes
Background: Training the old-age home staff is essential in raising geriatric mental health care standards in India. Inadequate knowledge on ageing and psychosocial interventions is a significant issue in old-age homes. Old-age home staff must know how to provide individualized psychosocial care and support for older adults. Hence this study aimed to test the feasibility of the psychosocial care training program for the staff working in old-age homes. Methods: A quasi-experimental research design (pre-post without a control group) was used. Forty-two staff members participated. Mary Starke Harper Aging Knowledge Exam (MSHAKE) and structured checklist to measure the staffs knowledge on ageing, psychosocial interventions, welfare legislations, schemes, and support services were administered before, immediately after, and two months after the program and the self-efficacy checklist was administered immediately and two months after the program, to examine the efficacy of the program. Results: Significant improvement was found in the ageing knowledge and the knowledge of psychosocial intervention and psychosocial care. These improvements continued for two months (p <.001). Similarly, their self-efficacy in managing such problems was also sustained across two post-measurements (p =.045). Conclusions: Face-to-face training programs would enhance the knowledge of the old age home staff. This Psychosocial Care Training module can be used for training old age home staff to address various psychosocial needs, concerns and other psychosocial problems of the residents. 2023 The Author(s). -
Increasing underutilised data in India: Opportunities and challenges
India, a country with a population of 1.33 billion has observed a substantial increase in the number of smart phones and internet users. This increase in internet users has not only changed the way Indian spend their time but has also led to generation of huge chunks of structured and unstructured data in India. In todays world where data of consumers is significant, this rise of internet users in India can change the game. This study focuses on how this increase in underutilised data in India, especially unstructured data can provide various opportunities and challenges to businesses, government and healthcare sectors in India. 2019 SERSC. -
The Jigsaw of Capital Structure
European Journal of Business and Management Vol. 5, No.13, pp. 192-197, ISSN No. 2222-288X -
Determinant of Capital Structure in Indian Manufacturing Sector
Asia-Pacific Journal of Management Research and Innovation Vol. 8, No. 3. pp 265-269, ISSN No. 2319-510X -
Generalized viscoelastic flow with thermal radiations and chemical reactions
Background: A generalized model of mathematical nature is considered to address the viscoelastic flow problem using fractional derivatives. Control/freedom of the flow mechanism is achieved with these derivatives. In simulations of industrial interest, more variations are available with fractional derivatives when compared with ordinary derivatives. Relaxation times are incorporated to handle the abrupt changes in the flow domain. Fluid flow is carried out under the influence of thermal radiations and when a heat source or sink is present. Chemical reactions of the first order are observed in the mathematical modeling of the flow. Methods: Flow is induced with the movement of the lower surface while applying force on the x-plane. Simulations of the governing mathematical problem are computed with the combination of finite element and finite difference algorithms. Significant Findings: It is noted that velocity, temperature, and concentration change with the variation of fractional order derivatives which was not possible with the classical derivatives. Moreover, with greater relaxation times, velocity, temperature, and concentration remained at a lower level. The modeled mechanism can be considered to avoid costly trials in chemical and polymer casting industries. 2023 Elsevier B.V. -
Modeling and computational fluid dynamic analysis on a non-AC bus coach system
The main objective of this paper is to reduce the drag force and enhance the uniform airflow inside an existing non-air-conditioning bus coach system. The redesigning of an existing bus carried out by considering the forces that reduce the moment of the bus. Modeling and meshing was carried out using solid works and Hypermesh software, respectively. Finally, the problem is simulated using Ansys fluent software and analysis is carried out for different bus models. The noteworthy findings state that the air resistance of the vehicle is found to be 812.74 N and coefficient of drag is 0.67 are less as compared to existing bus model. 2020 Wiley Periodicals LLC -
Effect of Magneto Convection Nanofluid Flow in a Vertical Channel
An analytical study of the effect of the magneto-convective flow of immiscible fluids through a vertical channel has been investigated in the presence of a chemical reaction. One region is saturated by electrically conducting incompressible fluid, and the other is saturated by nanofluid in a vertical channel with constant transport properties. The coupled nonlinear governing equations are solved by the regular perturbation method, with the Brinkman number as a perturbation parameter since its value is always less than unity. The results are discussed in detail using plots to analyze the flow phenomena. The increase in thermal and mass Grashof numbers enhances the fluid velocity and temperature profile, whereas Hartman number, solid volume fraction, and chemical reaction parameters exhibit the opposite effect. The effect of an increase in the nanoparticle volume fraction opposes the fluid flow and diminishes the temperature distribution due to the enhanced viscosity of the nanofluid. The Author(s), under exclusive licence to Springer Nature India Private Limited 2024. -
Determination of heavy metals in various tissues of locally reared (country) chicken in major districts of Karnataka, India: Assessment of potential health risks
Food is one of the most prevalent ways that humans are exposed to metals. Heavy metals including cadmium, iron, zinc, lead, and mercury are harmful to humans and have a detrimental impact on health because they accumulate in biological organs. The concentration levels of these heavy metals were tested in different edible parts of the country (locally raised) chicken from various districts in Karnataka, India, namely Bengaluru, Tumakuru, Mangaluru, and Udupi, using an Atomic-Absorption Spectrophotometer (AAS). Heavy metal concentrations in various chicken parts were found to be below detectable limits (BDL)-0.0062, 0.027-3.178, and 0.262-2.103 ppm for Cd, Fe, and Zn, respectively, whereas Hg and Pb were BDL. The content of Zn was found to be significantly higher in all chicken samples from all examined districts, followed by Fe and Cd. Hg and Pb concentrations, on the other hand, were below the detection level in all samples. The estimated daily intakes (EDIs) of the observed metals from country chicken consumption were found to be lower than their respective FAO/WHO reference oral doses (RfD). The non- carcinogenic health hazards posed by the tested metals to the target population were estimated using the Hazard Quotient (HQ) and Hazard Index (HI) values. The HQ and HI values observed in this estimation were less than one, indicating that exposure to these heavy metals through the consumption of country chicken is unlikely to provide possible health concerns to the examined regions human population. 2023, Universidade Federal do Parana. All rights reserved. -
Psychological Problems Among Children Three Years After the Earthquake in Nepal
Background: Frequent disasters and weak mental health system pose a risk to psychological health in Nepal. In 2015, a massive earthquake of 7.6 magnitude occurred in Nepal, which caused large scale destruction to human life and property. Limited research in children after disasters in Nepal prevent health professionals from implementing new evidence-based trauma treatments. Aim: The study aimed to identify the long term emotional problems experienced by earthquake-affected children in Nepal. The role of gender, severity of exposure, socioeconomic status and type of family in relation to emotional problems were also examined in the selected group. Methods: A purposive sampling was used to select 454 children (4th and 5th standard) from two highly affected wards in Kathmandu Metropolitan City. Information about exposure to the earthquake was collected from children using the Level of Exposure Scale while the parents completed the Nepali version of the Strengths and Difficulties Questionnaire (SDQ/ 4-17). Results: The effect of exposure to the earthquake was identified in the children even after three years. Boys had higher conduct, hyperactivity-inattention and peer problems while girls had high pro-social behaviour. Emotional problems were greater for those belonging to a lower socio-economic status. Among the variables, gender was a better predictor of emotional problems in earthquake-affected children. Conclusions: Emotional problems such as conduct problems, hyperactivity-inattention, peer problems are present in the earthquake-affected children in Kathmandu. Future researchers and clinicians need to monitor the children affected by the earthquake to recognise vulnerable groups and implement appropriate trauma-focused interventions. 2021, Indian Association for Child and Adolescent Mental Health. All rights reserved. -
Sexual violence in cyberspace: breaking the silence of international law
The increasing dependence of the world on digital technology and the internet has consequently led to the juxtaposition of the problematic social structure in online transactions and communications. This has resulted in increasing cases of cybersexual violence against women. The article argues that the effects of cybercrimes are transnational and, therefore, the traditional domestic criminal law is rather inept in preventing crime and punishing offenders. This increases the obligation of international law, which has so far remained silent on the issue. The articles conclusion suggests that the proposed World Convention on Cybercrime should include cybersexual violence as a core crime. This would serve as a beginning for addressing the threat, effect, and extent of the crime of cybersexual violence. The article concludes that the masculinist normative structure of international law is to blame for its culture of silence. Copyright 2024 Inderscience Enterprises Ltd. -
Characterization of signed paths and cycles admitting minus dominating function
Let G = (V, E, ?) be a finite signed graph. A function f: V ? {?1, 0, 1} is a minus dominating function (MDF) of G if f(u) + Pv?N(u) ?(uv)f(v) ? 1 for all u ? V. In this paper we characterize signed paths and cycles admitting an MDF. 2020 Azarbaijan Shahid Madani University -
Hi line analysis of Herbig Ae/Be stars using X-Shooter spectra
Herbig Ae/Be stars are intermediate-mass pre-main sequence stars undergoing accretion through their circumstellar disk. The optical and infrared (IR) spectra of HAeBe stars show Hi emission lines belonging to Balmer, Paschen and Brackett series. We used the archival X-Shooter spectra available for 109 HAeBe stars from Vioque et al. (2018) and analysed the various Hi lines present in them. We segregated the stars into different classes based on the presence of higher-order lines in different Hi series. We discussed the dependence of the appearance of higher-order lines on the stellar parameters. We found that most massive and younger stars show all the higher-order lines in emission. The stars showing only lower-order lines have Teff< 12 , 000 K and an age range of 510 Myr. We performed a case B line ratio analysis for a sub-sample of stars showing most of the Hi lines in emission. We noted that all but four stars belonging to the sub-sample show lower Hi line ratios than theoretical values, owing to the emitting medium being optically thick. The Hiline flux ratios do not depend on the stars spectral type. Further, from the line ratios of lower-order lines and Paschen higher-order lines, we note that line ratios of most HAeBe stars match with electron density value in the range of 10 9 10 11 cm - 3 . The electron temperature, however, could not be ascertained with confidence using the line ratios studied in this work. 2023, Indian Academy of Sciences. -
Disentangling the two sub-populations of early Herbig Be stars using VLT/X-shooter spectra
Context. Early Herbig Be (HBe) stars are massive, young stars accreting through the boundary layer mechanism. However, given the rapid (<2 Myr) evolution of early Herbig stars to the main-sequence phase, studying the evolution of the circumstellar medium around these stars can be a cumbersome exercise. Aims. In this work, we study the sample of early (B0-B5) HBe stars using the correlation between H? emission strength and near-infrared excess, complemented by the analysis of various emission features in the X-shooter spectra. Methods. We segregate the sample of 37 early HBe stars based on the median values of H? equivalent width (EW) and near-infrared index (n(J-H)) distributions. The stars with |H? EW| > 50and n(J-H) > -2 are classified as intense HBe stars and stars with |H? EW| < 50and n(J-H) < -2 as weak HBe stars. Using the VLT/X-shooter spectra of five intense and eight weak HBe stars, we visually checked for the differences in intensity and profiles of various HI and metallic emission lines commonly observed in Herbig stars. Results. We propose that the intense HBe stars possess an inner disk close to the star (as apparent from the high near-infrared excess) and an active circumstellar environment (as seen from the high H? EW value and presence of emission lines belonging to FeII, CaII, OI, and [OI]). However, for weak HBe stars, the inner disk has cleared, and the circumstellar environment appears more evolved than for intense HBe stars. Furthermore, we compiled a sample of ~58 000 emission-line stars published in Gaia DR3 to identify more intense HBe candidates. Further spectroscopic studies of these candidates will help us to understand the evolution of the inner (approximately a few au) disk in early HBe stars. The Authors 2023. -
Emission line star catalogues post- Gaia DR3: A validation of Gaia DR3 data using the LAMOST OBA emission catalogue
Aims.Gaia Data Release 3 (DR3) and further releases have the potential to identify and categorise new emission-line stars in the Galaxy. We perform a comprehensive validation of astrophysical parameters from Gaia DR3 with the spectroscopically estimated emission-line star parameters from the LAMOST OBA emission catalogue. Method. We compare different astrophysical parameters provided by Gaia DR3 with those estimated using LAMOST spectra. By using a larger sample of emission-line stars, we performed a global polynomial and piece-wise linear fit to update the empirical relation to convert the Gaia DR3 pseudo-equivalent width to the observed equivalent width, after removing the weak emitters from the analysis. Results. We find that the emission-line source classifications given by DR3 is in reasonable agreement with the classification from the LAMOST OBA emission catalogue. The astrophysical parameters estimated by the esphs module from Gaia DR3 provides a better estimate when compared to gspphot and gspspec. A second degree polynomial relation is provided along with piece-wise linear fit parameters for the equivalent width conversion. We notice that the LAMOST stars with weak H? emission are not identified to be in emission from BP/RP spectra. This suggests that emission-line sources identified by Gaia DR3 are incomplete. In addition, Gaia DR3 provides valuable information about the binary and variable nature of a sample of emission-line stars. 2022 EDP Sciences. All rights reserved. -
Discovery of 2716 hot emission-line stars from LAMOST DR5
We present a catalog of 3339 hot emission-line stars (ELSs) identified from 451 695 O, B and A type spectra, provided by LAMOST Data Release 5 (DR5). We developed an automated Python routine that identified 5437 spectra having a peak between 6561 and 6568 False detections and bad spectra were removed, leaving 4138 good emission-line spectra of 3339 unique ELSs. We re-estimated the spectral types of 3307 spectra as the LAMOST Stellar Parameter Pipeline (LASP) did not provide accurate spectral types for these emission-line spectra. As Herbig Ae/Be stars exhibit higher excess in near-infrared and mid-infrared wavelengths than classical Ae/Be stars, we relied on 2MASS and WISE photometry to distinguish them. Finally, we report 1089 classical Be, 233 classical Ae and 56 Herbig Ae/Be stars identified from LAMOST DR5. In addition, 928 B[em]/A[em] stars and 240 CAe/CBe potential candidates are identified. From our sample of 3339 hot ELSs, 2716 ELSs identified in this work do not have any record in the SIMBAD database and they can be considered as new detections. Identification of such a large homogeneous set of emission-line spectra will help the community study the emission phenomenon in detail without worrying about the inherent biases when compiling from various sources. 2021 National Astronomical Observatories, CAS and IOP Publishing Ltd.. -
Border Region Railway Development in Sino- Indian Geopolitical Competition
India and China share about 3,488 km long International Boundary, which has three sectors: Western, Middle and Eastern. The Eastern sector comprises two Northeastern states, that is, Arunachal Pradesh measuring 1,124 kms and Sikkim measuring 219 kms, respectively. Due to recent changes in the geopolitical relationship with China, border management and transport infrastructure development have occupied centre stage. In recent years, the Government of India has taken initiatives to develop railway infrastructure in Northeast India. The study will focus on the role of railway transportation in Sino-Indian geopolitical competition. The study is based on secondary data collected from the office of General Manager, Northeast Frontier Railway, the Census of India and reports of Memorandums of Understanding between India and China. The study reveals that railway infrastructure along the border creates geo-psychological pressures on both countries, influencing the divergent geopolitical relationship between India and China. Railway diplomacy is a tool kit of critical geopolitics which reveals the contours of geopolitical competition in borderlands. 2023 Indian Council of World Affairs(ICWA). -
Rayleigh-B nard convection in Casson and hybrid nano uids: An analytical investigation
The thermal Rayleigh-Bard convection (TRBC) in two different fluids namely Casson fluid and hybrid nanofluid is investigated analytically. The stability analysis is performed in both linear and non-linear form. The nanofluid properties like thermal conductivity, viscosity, thermal expansion coefficient and density are considered to be functions of the volume fraction of nanoparticles whereas the same properties of Casson fluid are assumed to be constant. The amount of heat transfer is analyzed in the non-linear analysis using the generalized Lorenz model. The influence of Casson fluid parameter and nanoparticles (single and or binary) which affect the onset of convection is analyzed. It is found that hybrid nanofluid delays the convection and will further enhance the heat transfer rate. Also, the Casson parameter advances the convection while it reduces the heat transfer rate. 2019 by American Scientific Publishers. -
Facile green synthesis of semiconductive ZnO nanoparticles for photocatalytic degradation of dyes from the textile industry: A kinetic approach
One-pot, facile and green synthesis of zinc oxide nanoparticles are synthesized using cow dung as fuel by combustion procedure. The synthesized material is characterized by using various techniques such as XRD, FTIR, UV, FESEM, and EDX. To assess the photocatalytic efficacy of the as-synthesized material, harmful cationic and anionic dyes such as methylene blue (MB) and alizarin red S (AZ) dyes, respectively, are selected as benchmark dyes. The influence of light source, dye concentration, photocatalyst dosage, and pH value on the efficiency of photocatalyst and kinetics of photodegradation are systematically studied. The photodegradation results revealed that the synthesized ZnO NPs exhibited removal efficiency of MB and AZ dyes upon irradiation with UV light. Concisely, the removal efficacy of the ZnO NPs under UV light irradiation exhibited an MB and AZ degradation of 99.9% and 96.8%, respectively. A reasonable photo-catalytic mechanism for the high photodegradation efficacy of MB and AZ dyes by the prepared photocatalyst is also proposed. The green fabricated photocatalyst is promising material and could be applied for waste-water remediation and other ecological applications. 2022 -
Photocatalytic and eco-emission applications of green synthesized ZnO-CB nanoparticles
Herein, we report the synthesis of ZnO nanoparticles (ZnO-CB NPs) by employing the solution combustion method using an aqueous extract of brinjal calyxes as fuel. Characterization techniques, such as X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FTIR), UVvisible spectroscopy, and Scanning electron microscopy (SEM), were used to investigate the structural, optical, and morphological properties of synthesized nanoparticles, respectively. Highly porous hexagonal crystalline ZnO-CB NPs with less than 7 nm particle size were obtained. The photocatalytic performance of synthesized material is measured with Malachite green (MG), Basic brown 1 (BB1), and Acid orange 36 (AO36) as benchmark dyes. It showed that the synthesized material worked effectively under pH 10 with UV light irradiation. The synthesized ZnO-CB NP shows good removal effectiveness of the MG, BB1, and AO36 dyes with 99.3 %, 99.6 %, and 99.5 %, respectively, which can be promising photocatalysts for ecological applications such as wastewater remediation. Further, the synthesized ZnO-CB NP was used as blends in the methyl ester of Millettia pinnata oil (MPME), which is blended 20 % with commercial diesel (MPME20). The synthesized ZnO-CB NP was added to the MPME20 in varying amounts to ascertain its effects on the quality of emissions of various greenhouse gases such as hydrocarbons, COx, and NOx. Moreover, brake thermal efficiency (BTHE) and brake-specific fuel consumption (BSFC) were studied for the blends. The blend MPME20 with 25 mg of ZnO-CB NP, i.e., MPME20-25 mg, ZnO-CB, displays the best performance and reduced emissions. 2024 The Author(s)