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Chemical leaching of an indian bituminous coal and characterization of the products by spectroscopic techniques
Fourier transform infrared (FTIR) spectra of high volatile bituminous coal as well as their insoluble organic matter, obtained by chemical leaching with HF, EDTA and acid mixture (HF + HCl and HF + HNO3) were recorded between 500 and 4000 cm-1. UV-Visible-NIR spectroscopy was used to study the sample and its leached products in the 200-800 nm wavelength region. Oxygen containing structures were observed in the 1800-1000 cm-1 zone, aliphatic hydrogen in the 2920-2800 cm-1 zone, aromatic outof- plane structure in the 900-670 cm-1 zone. A great abundance of C=C structure was noticed at 1600 cm-1 region, while clay and silicate minerals were identified in the 540 cm-1 and 1030 cm-1 region. With chemical leaching silicate bands showed a decrease in intensity and were least for EDTA and HF leached samples. The UV-Visible -NIR spectrum showed absorption maximum at 235-270 nm and was shown a red shift with leaching. The II-II* electronic transitions of the poly-nuclear aromatic hydrocarbons was responsible for the absorption at 680 nm. The weak bands observed in the visible region (400-500 nm) were due to the presence of SO2 in the sample and decreased with chemical leaching. It was evident from the results that amongst the leachants used, hydrofluoric acid and acid mixture had significant effect in removing the mineral matter and oxygenated functional groups. -
Chemical leaching of an Indian bituminous coal and characterization of the products by vibrational spectroscopic techniques
High volatile bituminous coal was demineralized by a chemical method. The vibrations of the "aromatics" structure of graphite, crystalline or non-crystalline, were observed in the spectra at the 1600 cm -1 region. The band at 1477 cm -1 is assigned as VR band, the band at 1392 cm -1 as VL band and the band at 1540 cm -1 as GR band. Graphite structure remains after chemical leaching liberates oxygenated functional groups and mineral groups. The silicate bands between 1010 and 1100 cm -1 are active in the infrared (IR) spectrum but inactive in the Raman spectrum. Absorption arising from C-H stretching in alkenes occurs in the region of 3000 to 2840 cm -1. Raman bands because of symmetric stretch of water molecules were also observed in the spectrum at 3250 cm -1 and 3450 cm -1. Scanning electron microscopy analysis revealed the presence of a graphite layer on the surface. Leaching of the sample with hydrofluoric acid decreases the mineral phase and increases the carbon content. The ash content is reduced by 84.5wt% with leaching from its initial value by mainly removing aluminum and silicate containing minerals. University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg 2012. -
Chemical Reaction Effects on Nano Carreau Liquid Flow Past a Cone and a Wedge with Cattaneo-Christov Heat Flux Model
Chemical reaction aspect is utilized for heat mass transfer analysis of nano non-Newtonian liquid flow past a cone and a wedge. Flow is steady, laminar and two dimensional created due to a cone and a wedge. The Carreau liquid and Cattaneo-Christov heat flux models are utilized. The magneto-nano Carreau liquid material occupies the porous space. The relevant PDEs are rendered into coupled non-linear ODEs via appropriate transformations before treated them numerically through Runge-Kutta and Newton's method. The computed results are plotted for employing the various values of physical constraints on the profiles of velocity, temperature and nanoparticle volume fraction. Moreover, vitiation of the friction factor, Nusselt number and Sherwood number against physical parameters are presented numerically. It is figured out that convective heating and Brownian motion effects are constructive for thermal boundary layer growth. Aspect of chemical reaction is significant to control the solute layer growth and mass transfer rate. 2017 Walter de Gruyter GmbH, Berlin/Boston. -
Chemical reaction induced Rayleigh-Benard convection in a densely packed porous medium saturated with a couple-stress fluid
The problem of Rayleigh-Benard convection in a couple-stress fluid saturated densely packed porous medium with chemical reaction is studied within the framework of linear stability analysis. Only infinitesimal disturbances are considered. The linear stability analysis is based on the normal mode technique. The Darcy law is used to model the momentum equation. Closed form solution for the basic quiescent state is first obtained. The principle of exchange of stabilities is valid and the existence of oscillatory instability is ruled out. The expression for the stationary media-Darcy-Rayleigh number is obtained as a function of the governing parameters, viz., the wave number, the couple-stress parameter and the Frank-Kamenetskii number. The Galerkin method is used to determine the eigenvalues. The effect of various parameters on the stability of the fluid layer is discussed through figures. -
Chemical Reaction-Driven Ferroconvection in a Porous Medium
The effect of chemical reaction on the outset of convection of a ferromagnetic fluid in a horizontal porous layer which is heated from below is studied using small perturbation method. Assuming an exothermic zero-order chemical reaction, the eigenvalues are found by employing the Galerkin method. The effect of magnetic parameters and Frank-Kamenetskii number is discussed. It is established that both magnetic forces and chemical reaction accelerate the threshold of ferroconvection. Further, the fluid layer is destabilized marginally when the nonlinearity of magnetization is strong enough. 2021, Springer Nature Singapore Pte Ltd. -
CHEMICALLY DRIVEN RAYLEIGH-B??NARD CONVECTION IN A CHEMICALLY DRIVEN RAYLEIGH-B??NARD CONVECTION IN A SPARSELY DISTRIBUTED POROUS MEDIUM SATURATED WITH A COUPLE-STRESS FLUID SPARSELY DISTRIBUTED POROUS MEDIUM SATURATED WITH A COUPLE-STRESS FLUID
The problem of Rayleigh-Benard convection in a couple-stress fluid saturated sparsely distributed porous medium with chemical reaction is studied within the framework of linear stability analysis. Only infinitesimal disturbances are considered. The linear stability analysis is based on the normal mode technique. The Darcy-Brinkman law is used to model the momentum equation. Closed form solution for the basic quiescent state is first obtained. The principle of exchange of stabilities is valid and the existence of oscillatory instability is ruled out. The expression for the stationary media-Rayleigh number is obtained as a function of the governing parameters, viz., the wave number, the couple-stress parameter, the Frank-Kamenetskii number, the porous parameter and the Brinkman number. The Galerkin method is used to determine the eigenvalues. The effect of various parameters on the stability of the fluid layer is discussed through figures. -
Chemically driven Rayleigh-Benard convection in a sparsely distributed porous medium saturated with a couple-stress fluid
The problem of Rayleigh-Benard convection in a couple-stress fluid saturated sparsely distributed porous medium with chemical reaction is studied within the framework of linear stability analysis. Only infinitesimal disturbances are considered. The linear stability analysis is based on the normal mode technique. The Darcy-Brinkman law is used to model the momentum equation. Closed form solution for the basic quiescent state is first obtained. The principle of exchange of stabilities is valid and the existence of oscillatory instability is ruled out. The expression for the stationary media-Rayleigh number is obtained as a function of the governing parameters, viz., the wave number, the couple-stress parameter, the Frank-Kamenetskii number, the porous parameter and the Brinkman number. The Galerkin method is used to determine the eigenvalues. The effect of various parameters on the stability of the fluid layer is discussed through figures. -
Chernobyl Disaster Optimizer-Based Optimal Integration of Hybrid Photovoltaic Systems and Network Reconfiguration for Reliable and Quality Power Supply to Nuclear Research Reactors
In view of the complexity and importance of nuclear research reactor (NRR) installations, it is imperative to uphold high standards of reliability and quality in the electricity being supplied to them. In this paper, the performance of low-voltage (LV) distribution feeders integrated with NRRs is improved in terms of reduced distribution loss, improved voltage profile, and reduced greenhouse gas (GHG) emissions by determining the optimal location and size of photovoltaic (PV) systems. In the second stage, the power quality of the feeder is optimized by reducing the total harmonic distortion (THD) by optimally allocating D-STATCOM units. In the third and fourth stages, the reliability and resilience aspects of the feeder are optimized using optimal network reconfiguration (ONR) and by integrating an energy storage system (ESS). To solve the non-linear complex optimization problems at all these stages, an efficient meta-heuristic Chernobyl disaster optimizer (CDO) is proposed. Simulations are performed on a modified IEEE 33-bus feeder considering the non-linear characteristics of NRRs, variability of the feeder loading profile, and PV variability. The study reveals that the proposed methodology can significantly improve the service requirements of NRRs for attaining sustainable research activities. 2024 by the authors. -
Chest Diseases Prediction from X-ray Images using CNN Models: A Study
Chest Disease creates serious health issues for human beings all over the world. Identifying these diseases in earlier stages helps people to treat them early and save their life. Conventional Neural Networks play an important role in the health sector especially in predicting diseases in the earlier stages. X-rays are one of the major parameters which help to identify Chest diseases accurately. In this paper, we study the prediction of chest diseases such as Pneumonia, COVID-19, and Tuberculosis (TB) from the X-ray images. The prediction of these diseases is analyzed with the support of three CNN Models such as VGG19, Resnet50V2, and Densenet201, and results are elaborated in the terms of Accuracy and Loss. Though all three models are highly accurate and consistent, considering the factors like architectural size, training speed, etc. Resnet50V2 is the best model for all three diseases. It trained with F1 score accuracies of 0.98,0.92,0.97 for pneumonia, tuberculosis, covid respectively. 2021 -
Child friendly schools: Challenges and issues in creating a positive and protective school environment
Schools are considered to be one of the safest places where children are seen on a daily basis and are under the supervision of teachers who are trained and equipped caregivers. Children are victims of all forms of abuse, punishment, neglect, discrimination, and ill-treatment within the school setting. Though there are various policies and programmes at international and national levels, addressing child protection has been a serious challenge for every community. Children need to be protected and any acts that hamper their well-being and safety need to be curbed. The objective of this chapter is to critically evaluate school-based child-protection programmes and suggest a model of child protection through positive schooling. Positive schooling is an approach to create a healthier and safer school environment. Positive schooling emphasises inclusiveness, strength-based education, developing character strengths, creating least restrictive environments, and fostering well-being among the school community, including students and teachers. It aims at creating a positive culture where every learner gets equal opportunities to learn and develop. It gives value to overall well-being of the individual and happiness within the learning environment. It promotes positive teaching strategies without the use of punishment and pressure. The positive culture within the school environment would promote peer support and collaboration, preventing bullying and abuse. Learners and facilitators would respect and support each other, focusing on strengths rather than weakness, which would, in turn, create an inclusive environment accommodating everyone. The chapter also highlights the need for: trained professionals, like counsellors, in school settings; stronger school-based polices; and the need for collaboration among school administrators, counsellors, teachers, and parents. Springer Nature Singapore Pte Ltd. 2018. -
Child Mental Health in the Milieu of Online Education
The aim of this chapter is to examine the impact of online education on mental health of children, and explore methods to improve the same. With the advent of COVID-19 pandemic, major overhauls were made in day-to-day life including work, home, and education. Shift to online mode of instruction became the primary, if not the only, channel of education. This drastic shift has led to issues like limited social interaction, learning gaps due to insufficient in-person interaction, excessive screen time on devices, and decreased physical activity, which can impact mental health of children. This chapter will explore the impact of online learning on the mental health of children from both mental ill-health and well-being perspectives, the role of parents, teachers, and educational systems, and challenges and opportunities presented by the situation. Further to this, the ways to safeguard and improve mental health of children in the milieu of online education will be discussed. The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2022. -
Child mental health: The role of different attributional styles
Background: High prevalence of mental health issues in the twenty-first century accounts for a lion share in the worldwide burden of disease. There is an alarming decrease in the onset of half of the mental health problems. Hence, it is necessary to explore the current situation and figure out the causes and preventive measures as well as the appropriate mental health enhancement measures. Individual characteristics, such as thinking patterns and perception, have an impact on the mental health. Attributional style is one source of cognitive vulnerability which influences mental health disorders. Therefore, the present study examines whether there are any variations in the mental health of children with different attributional styles. Methods: The current research adopted a cross-sectional research design and selected 150 school going students [74 males and 76 females] between 10-13 years of age as participants. The Child Attributional Style Questionnaire [CASQ], Satisfaction with Life Scale-Children [SWLS-C], Brief Resilience Scale, and Revised Child Anxiety and Depression Scale [RCADS] are used to gather information. Results: The results indicated that children with a pessimistic attributional style experienced more depression and generalized anxiety than children with other two attributional styles. In terms of gender differences in mental health, female students with pessimistic attributional style significantly differed from their counterparts on depression [?2 [2] = 10.131, p = 0.006] and separation anxiety [?2 [2] = 6.456, p = 0.040]. Conclusion: Attributional style seems to have a significant role in depression and anxiety in female children. Although male children did not show any statistically significant results, they were more likely to be pessimistic in terms of their attributional style, which makes them vulnerable to mental health issues. 2020, Indian Association for Child and Adolescent Mental Health. All rights reserved. -
Child sexual abuse prevention involving mothers: A Quasi-experimental study with Protection Motivation Theory-based intervention
Child sexual abuse (CSA) is a worldwide problem. The safety of children is everybody's responsibility. Parental and family involvement is crucial in the CSA prevention process. Parental lack of knowledge may increase the risk of abuse among children. Educating parents is crucial as children are mostly dependent on them. The role of mothers in educating children on CSA is of relevance as they are identified as more sensitive and responsible caregivers. The present study aimed to promote knowledge and attitude towards CSA prevention among mothers through a psychoeducation program. A pre- and posttest design (n = 67) was used with an intervention based on Protection Motivation Theory (PMT). A CSA knowledge and attitude scale was developed for the assessment of the participants for the study. There were significant changes in knowledge and attitude among the participants after the intervention. The prevention of CSA will be effective with knowledge gains after the PMT-based intervention. The intervention programs that involve mothers in CSA education have benefits. The findings of this study can be helpful to incorporate public health approaches to devise evidence-based parental programs in community settings. 2022 Wiley Periodicals LLC. -
CHILDREN INFLUENCE ON FAMILY PURCHASE DECISION
There are various aspects of the children influence on family purchase decision and it depends on a lot of parameters and situations. The children exercise various methods to influence parent??s decision. The children influence varies from products to products. It also depends on parent??s education, profession, income, single parent working or both parent working, number of working hours per week and type of family. The pocket money also contributes in the children??s influence. This research considers the children in the age group of 8-12. The Descriptive statistics is used to summarize variables in terms of central tendency and measure of dispersion. The Reliability test has been done using Cronbach??s alpha. Pearson??s Product correlation, one way ANOVA, Two-way ANOVA has been done using SPSS for Windows (version 18.0). The Linear regression is used to prove the causality between Independent variables on Dependent variable. The strategy adopted by children is mostly persuasive. The children??s influence is maximum for products bicycle, Ice Creams/chocolates/Juice and CDs/DVDs. There are few products like CDs/DVDs, video games and hobby activities which are used by the whole family and still children influence is higher than their parents on family purchase decision. It is the unanimous opinion from both parents and children that the children influence depend on profession as well as on the products. The ANOVA analysis on parent??s perception on children influence indicates that parent??s income impacts the children??s influence. The ANOVA analysis on parent??s perception on children influence indicates that parent??s working hour impacts the children??s influence. The relation between children influence and How many hours a week do you work average, Total Family Income and Amount you get from your parent on spending is linear. The pocket money, children get, is having highest impact on children influence. The second most influential parameter is the number of hours the parents work per week. -
Children Witnessing Violence in India: Nature, Risk Factors, Impact and Prevention Strategies
Children witness various degrees and intensities of violations and violence along with a hoard of environmental stressors. Such a spectrum of violence includes disturbing family environments, witnessing adults, including parents and family members, indulge in violence and abusive behaviours and direct or vicarious exposure to violence outside the home. The chapter aims to provide an overview of the nature and impact of witnessing violence. The frequency, type, intensity and the child's relationship with the people involved or impacted by the violence can determine the impact on a child's mental health and development. Children may witness distressing events in their daily lives like the loss of a loved one or watching adults take up challenging tasks, which may help them be resilient and learn coping skills with appropriate support. Long-term exposure to witnessing violence and trauma can lead to severe emotional and developmental difficulties. Such direct or vicarious exposure to varying degrees of violence may cultivate a culture of fear, repression and silence around the children. These difficulties may be similar to those of children who are direct victims of abuse. Witnessing violence has also been linked to anxiety and depression. Children growing up in such environments are at higher risk of normalizing violence and growing into abusive adults. Poverty, cultural factors, parenting, schooling, and policies can largely determine such risks for children. The paper discusses the preventive and promotive approaches at the school, family and community levels. Education and empowerment of adults in the child's environment can be the best preventative approach. Existing policies and programmes in India for children need to bring in more robust initiatives to identify, report, prevent and protect children witnessing violence. The needs and concerns of children witnessing violence and prevention approaches should be part of courses in helping professionals training and curriculum. The chapter calls for the necessity of individual and community-based interventions in terms of need-based models for addressing the mental health needs of children. The chapter strongly recommends the need for addressing mental health education for families and schools. The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2022. -
Children's Well-Being in Traditional Vs. Montessori Schools. A test of Self-Determination Theory
The present study is a test of Self -Determination theory, which is well established in the field of education with a huge body of empirical evidence to support its assumptions that when the three universal psychological needs (Autonomy, Competence & Relatedness) of a child are met they will grow and function optimally leading to enhanced well-being. It is evident that Montessori philosophy is overlapping with the components of SDT. This study was conducted to examine the extent to which the three psychological needs are satisfied in Montessori schools in comparison to the Traditional schools. A purposive sample size of 80 children in elementary grades was selected from both Montessori and Traditional schools. Perceived support experienced by the children and their Well-Being was determined to establish the assumption of the SDT. The results showed that children in Montessori schools experienced greater satisfaction of needs when compared to traditional school children. However, the well-being of children from both school types didn???t vary much and the causes can be attributed to factors outside classroom. These findings have some strong implications for policy makers, educators and parents. -
Chinese maritime relations with Malabar Coast, 12001500 AD: A quest for naval dominance
China has had a long history of maritime expedition. Its Indian Ocean connectivity, long before European explorers arrived at the Malabar Coast, had made significant impact on the maritime trade in the Indian Ocean region. Chinas expedition to the Southern Asia was aimed to expand the benevolence of Chinese emperor and to establish its suzerainty in maritime trade rather than to establish the permanent position on land. The political dynamics at home caused the rise and fall of the maritime might of China. The famous explorer, Zheng Hes expeditions represented Chinas ambition to expand its control over the Indian Ocean regions. The Malabar Coast with its geographical advantages had developed maritime activities enhancing its commercial fortunes. China had to accept the strength of Malabar kingdoms in terms of political power, trade and commercial advantages. Importantly, Malabar kingdoms did not accept the Chinese assertions of supremacy but engaged with the Chinese on equal terms. An attempt is made here to trace Chinas maritime strategy to expand their power beyond the immediate periphery and establish its supremacy in the Indian Ocean. 2019, 2019 National Maritime Foundation. -
ChIPSeq Analysis with Bayesian Machine Learning
ChIP-sequencing, otherwise called ChIP-seq, is a technique used to identify protein co-operations with DNA. A crucial advancement to the field of bio-informatics, ChIP sequencing is conducted in research labs around the world to get a better understanding of the way transcription factors and other associated proteins influence the gene in many biological processes and in tackling disease states. ChIP-seq is predominantly a field under the domain of biotechnology, however recent advancements and development of tools to process ChIP data have turned the study into one involving bio-informatics, allowing computer scientists and lab technicians to work on an otherwise scholarly field of biochemistry, molecular biology, microbiology and biomedicine. This report illustrates the predominant work-flow undertaken to sequence chromatin from a cell and to gain insights on the gene/protein of interest. Another aspect added is to use Machine Learning with Bayesian statistical techniques for Peak Calling. The different stages enumerated in this paper have been completed either with the R language or on a Web Server titled Galaxy.org. 2019 IEEE. -
Chitosan stabilized platinum nanoparticles: Synthesis, characterization and cytotoxic impacts on human breast cancer cells
Platinum nanoparticles are widely studied as a nanomedicine against many of the solid tumours. Due to their promising physicochemical properties, chitosan-stabilized platinum nanoparticles may exhibit exceptional cytotoxic effects on cancer cells. This article describes the synthesis and characterization of chitosan-stabilized platinum nanoparticles (Ch-Pt NPs) through a wet chemical method and in vitro studies of their anticancer effect on human breast cancer cells (MCF-7 cell line). Different analytical methods confirmed the formation of chitosan-stabilized platinum nanoparticles. The structural and surface morphological analyses were done using XRD, FTIR, TEM, FESEM, etc. Elemental analysis was done using XPS and EDX. The hydrodynamic diameter and zeta potential were determined using DLS and zeta analyzer. These platinum nanoparticles have a spherical shape and FCC structure with an average particle size of 3.4 nm and an average hydrodynamic diameter of 248 nm. The characteristic FTIR peaks of chitosan in the sample confirmed the capping of chitosan on the surface of the Pt NPs. The surface charge estimation using a zeta potential analyzer showed ?23.8 mV, elucidating the stability and dispersity of the as-synthesized Pt NPs. The in vitro cytotoxicity study using MTT assay revealed a non-toxic behaviour on normal L929 cell lines and a severe anti-proliferative activity on a human breast cancer (MCF-7) cell line with an IC50 value of 35.60 ?g/ml after 24 h of incubation. This result indicates a better anticancer therapeutic application against human breast cancer cells for the as-synthesized chitosan-stabilized platinum nanoparticles. 2024 Elsevier B.V. -
Chlorin e6 decorated doxorubicin encapsulated chitosan nanoparticles for photo-controlled cancer drug delivery
In the study we have reported the physico-chemical, photophysical and morphological properties of chlorin e6 (Ce6) decorated doxorubicin (DOX) encapsulated chitosan (CS)-tripolyphosphate (TPP) nanoparticles which prepared by ionotropic gelation method. The Ce6 physically loaded onto the nanoparticles by self-assembly of CS with TPP-DOX under aqueous conditions. The results from DLS studies highlights the prepared nanoparticles that possess the size in the range of 80120 nm. with negatively charged of ?6 mV. The SEM and AFM images showed 80120 nm size while the average size of the Ce6 decorated nanoparticles was found to be around 100130 nm. The absorption spectra of Ce6 decorated nanoparticles are similar when compared to free Ce6 which suggest there is no change in the Ce6 chromophore upon decoration. This nanoparticle showed high photostability and singlet oxygen generation (SOG). The Ce6 decorated and DOX encapsulated nanoparticles sizes and charges are in the range of 90130 nm and ?30 mV respectively. The nanoparticles showed high encapsulation efficiency towards DOX as well as pH controlled release. This has significant anti-proliferative activity against MCF-7 breast cancer cells after irradiation at near infra-red (NIR) ranges were evaluated. This could have potential applications in photo-controlled smart DOX delivery system for cancer treatment. 2019 Elsevier B.V.