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Green Synthesis of Nanoparticles Leading to the Biocontrol of Aedes Aegypti
Mosquitoes are the potential vectors of many diseases such as malaria, dengue, brain newlinefever, etc. There is a need to check the proliferation of the population of vector newlinemosquitoes to reduce vector-borne diseases by appropriate control methods. Nanotechnology, a promising field of research, opens up in the present decade and is expected to give major impulses to technical innovations. Over the past few decades, nanoparticles of noble metals such as silver exhibited significantly distinct physical, chemical and biological properties. Presently, there is a need for increased efforts to develop newer and more effective methods to control mosquito vectors. Due to different technical and operational reasons, the existing chemical and biological methods are not as effective as in the earlier period. Therefore, this study is designed to extract silver newlinenanoparticles from plant, fungal and bacterial species and assess their impact on the third and fourth-instar mosquito larvae and the adult mosquito (Aedes spp). The study has formulated a gel material that is composed of nanomaterials that exhibited promising properties to develop a nano gel product. The study is designed in a way to have an impact on the control of mosquito larvae using biologically synthesized nanoparticle formulations. Green synthesis is expected to show a higher yield of nano products that can be formulated in various forms to standardize the biocontrol of mosquito species. Bioinformatic studies revealed the good binding potential of the extracted bio compounds against the juvenile hormone binding proteins in A. aegypti. The study deduced meaningful outcomes that can benefit the environment by controlling the mosquito population and thereby reducing disease transmission in many developing countries. -
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Growth and characterization of certain III-VI compound semiconducting crystals
The rapid advances in solid-state physics over the last few decades have uncovered many effects in crystals,which have formed the basis of large industries. the availability of crystals from the natural resources is inadequate to meet the need of these industries and also does not give sufficient variety. This led to a great deal of research work on the method of production of crystals artificially. -
Growth and characterization of InBi1-xSbx InBi1-xTex and γ-In2Se3 crystals
Theory and innovating practices of crystal growth heralded cutting edge breakthroughs in the production of proficient crystals towards the advancement of science and technology. Unique characteristics and band structure provide great flexibility for structural design and band gap engineering of indium bismuthide (InBi) compounds. Substitution of antimony and tellurium elements results in the transition of InBi to a semiconducting state with narrow energy gap, making it suitable for optoelectronic devices. Need of eco-friendly sustainable processes concerning the elimination of hazardous materials bring and#947;-In2Se3 in the forefront of photovoltaic industry, due to its wide band gap as well as n-type conductivity. Thus, realizing the immense potential attributes of InBi1-xSbx, InBi1-xTex (x = 0-0.2) and and#947;-In2Se3 crystals, the present research was focussed on pioneering their growth and characterization.Horizontal directional solidification (HDS), being the versatile, inexpensive melt growth technique, was employed for obtaining InBi1-xSbx, and InBi1-xTex (x = 0-0.2) crystals. On the other hand, closed tube sublimation (CTS) was found to be most effective for deposition of and#947;-In2Se3 crystals. Platelet and spherulitic morphologies of and#947;-In2Se3 crystals have been grown by the vapor deposition for the first time, under different growth environments. Morphology, structure and quality of the as-grown crystals were studied, employing various scientific procedures such as X-ray diffraction (XRD), energy dispersive analysis by X-rays (EDAX), scanning electron microscopy (SEM), atomic force microscopy (AFM) and transmission electron microscopy (TEM). Transport parameters, melting point and phase purity have been evaluated with the aid of Hall effect measurement, four probe set up, differential scanning calorimetry (DSC) and Raman spectroscopy. Vickers indentation testing was utilized for the evaluation of microhardness and deformation characteristics. -
Growth and Characterization of Indium Monotelluride Crystals
Semiconductors have become an inevitable part of human life. The beginning of the modern electronic technology goes back to the invention and elaboration of the semiconductor-based transistor by Bardeen, Brattain and Shockley in 1948. Thereafter, electronics industry has grown and become one of the worlds largest commercial establishments. The increasing demands for smaller electronic devices with improved performance at lower costs drive the conventional silicon-based technology to its limits. To satisfy the requirements from the industry and to extend the applications of semiconductor devices, new materials and fabrication techniques have to be used. The development, specification and quality control of these materials often require a very delicate crystal growth process and specific characterizations, which will be critical to a successful design of an electronic device. The knowledge of structural, electrical and mechanical properties of materials is essential for making use of them in various electronic devices. The operating abilities of a large part of modern technological hardware are based on active and/or passive crystalline core pieces. The fabrication of such crystals is normally connected with the well established growth methods such as Bridgman, Czochralski, Verneuil, zone melting, top seeded solution growth (TSSG), re-crystallization techniques, etc. Bulk crystal growth techniques are used to grow large crystals from which substrates are sliced. Substrate availability is a critical component in the success of a technology. Hence, even in this era of thin films and epitaxial layers, bulk crystal growth from melt still upholds its significance and plays an important role in the development of semiconductor-based technologies. Solar cell technology, as a sustainable source of energy, has shown a tremendous growth in recent years. The most widely used commercial solar cells are made from single crystalline silicon and have efficiencies up to 26.5%. However, such single crystalline solar cells are relatively expensive with the silicon itself making up to 20-40% of the final cost. In the search for low-cost alternatives to crystalline silicon, a great deal of work is being carried out in tailoring the applicability of compound semiconductor materials, which offer advantages over silicon. Indium monotelluride (InTe) is a III-VI layered semiconductor, which is particularly suitable for photovoltaic use, because of its suitable band gap (1.16 eV), optical and transport properties. In addition, its cleaved surfaces do not need any additional treatment for p??n junction formation and are chemically inert under ambient conditions. The crystal structure of InTe is tetragonal with lattice parameters, a = b = 8.454 ??, and c = 7.152 ??. The direct nature of transition supports the maximum efficiency of the InTe based opto-electronic devices. Indium monotelluride (InTe) crystals have been crystallized using directional freezing technique by employing a two zone horizontal furnace. The compound charge used for the growth was synthesised from its constituent elements (In and Te). The structural and chemical investigations of the grown samples were performed using powder x-ray diffraction (XRD) technique and energy dispersive analysis by x-rays (EDAX). The dielectric constant, loss factor, AC conductivity and optical band gap of the grown InTe crystals were estimated from the capacitance measurements in the temperature range, 35-140??C. The frequency dependence of these dielectric parameters has been studied to understand the mechanism behind conduction. The mechanical strength of the cleaved samples of indium monotelluride was investigated using Vickers microhardness tester in the load range, 5-50 g, and the results obtained are discussed. The present research work titled ??Growth and characterization of indium monotelluride crystals has been organized into four chapters. Chapter 1 gives a brief introduction about the concepts of nucleation with regard to the crystal growth of semiconducting materials. The effects of thermodynamical parameters on the growth of crystals are explained. The theories of crystal growth along with the factors affecting the crystallization phenomenon are described in chapter 2. The principle behind the different crystal growth processes is outlined. An account on the various crystal growth techniques highlighting their special features is also given. A review of the present national / international status on the growth and characterization of InTe is presented. The description of directional freezing method, experimental procedure and the various characterization techniques used for the study are presented in chapter 3. Chapter 4 covers the results and discussions of the research findings. It ends with a reference section, wherein the literature reviews used are listed as per the international standards and the order of its appearance in the text. -
Growth and Characterization of Sb2Se3 and SnSe2 Crystals for Photovoltaic Applications
Tremendous development in crystal growth technology led to the production of good newlinequality samples for the design and fabrication of optoelectronic devices. As naturally available solids exhibit undesirable characteristics, the present research work deals with the artificial synthesis and characterization of defect free binary layered chalcogenide materials newline(LCMs) for photovoltaic (PV) applications. Antimony selenide (Sb2Se3) and tin diselenide newline(SnSe2) have gained special attention in the PV industry due to their eco-friendly, sustainable, and non-hazardous nature as well as the salient features such as moderate melting temperature, p-type conductivity with direct transition, optimum band gap and high newlineabsorption coefficient. Therefore, cost-effective synthesis was implemented to engineer bulk Sb2Se3 and SnSe2 crystals for the enhancement of optoelectronic parameters. Single crystal growth from melt allows the fabrication of large size samples under controlled environment. It gives rise to complexities in maintaining stable temperature for crystallization and newlineachieving chemical homogeneity, if multiple elements are present in the system. The newlinechallenges associated with Bridgman-Stockbarger and Czochralski methods for preparing bulk crystals include irregular heat flow, mechanical movement of furnace or crucible, thermal stress, etc. Moreover, reactivity of the melted material with the ampoule leads to structural irregularities. Hence, horizontal normal freezing (HNF), the facile and inexpensive melt growth technique was employed to explore the suitability of cleaved samples. Most of the vapor phase synthesis methods, especially, the chemical vapor deposition (CVD) deteriorates material quality, which adversely affects the physical properties due to the presence of contamination or foreign elements. But, the physical vapor deposition (PVD) process is favorable as it offers feasible instrumentation and yields stoichiometric specimens with supreme quality and fine-tuned characteristics. -
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Growth and physical properties of sb2 te3 and related thermoelectric materials
Research on crystal growth and characterization is inevitable to meet the requirements of the technological world, as there is a great demand for good quality samples free from flaws for application in newlinevarious fields which cannot be met by natural resources. The synthesis of newlinebulk crystals of Sb2Te3 compounds has intrigued the attention of the researchers in the present work, due to their diverse properties which provide boundless scope to develop innovative approaches towards the newlinedevelopment of devices with improved thermoelectric (TE) efficiency. The green technology of conversion of waste heat to electric current by the TE phenomena offers a noise-free alternative with low mechanical newlineand conduction losses for small scale refrigeration and power generation modules. Though, thermoelectric devices offer better reliability and durability, one of the major challenges is to develop a material system newlinewith high figure of merit (ZT) in the variable temperature ranges. From the research reports it is evident that, generally for scientific studies, conventional melt methods were used to grow bulk Sb2Te3 crystals, where nonstoichiometry, polycrystallinity and multi-phase formation raise problems. Furthermore, large fluctuations in TE properties have been exhibited by single crystals synthesized from the melt, which preclude their uses in devices. The ability to control as well as engineer various newlineproperties of Sb2Te3 depends on the choice of growth method, experimental tools and processes. Even though substantial work has been published on the studies of cleaved samples of crystals grown from the melt, the growth mechanism and TE investigations on vapor deposited platelet structures of Sb2Te3-xSx and Sb2-xInxTe3 have not been investigated so far. With the prime focus on vapor deposition as an alternative to melt methods to produce defect free, good quality stoichiometric and mechanically stable crystals with improved ZT, the research was aimed at growth and characterization of Sb2Te3 and related newlinethermoelectric materials. -
Health diagnosis of mango trees using image processing techniques
A Mango disease detection artificial intelligent model needs robust and effective newlinefeature extraction methods. The machine vision system has been designed for the newlineidentification of disease in plants from color leaf images. The research done proposes newlinenovel algorithms to extract color features Pseudo Color Regions and Texture Features newlineusing Pseudo Color Co-Occurrence Matrix. A new Mango dataset has been created and newlinealgorithms tested on it. An artificial intelligence model has also been created and tested on an existing disease dataset of Apple and Tomato plants. Results were compared with existing methods in the literature. The effectiveness of each statistical function was studied in classifying the pattern using a Support Vector Machine. For textures that are newlinedifferent like smooth new leaves, dry leaves, growth a Gray Level Co-occurrence based newlinestatistics was effective but values failed to discriminate in certain diseases. The proposed and implemented novel method which uses second-order statistics on a pseudo-color-based co-occurrence matrix has resulted in better classification. Pseudo Color Region feature is created using a novel intermediate data structure and found to be more effective than hue-based color features. It identifies dots, spots, patches and regions of different colors on the leaf and uses that as a feature vector to classify plant diseases. This generic method can be applied for early disease detection for plants and help farmers take corrective measures to avoid loss of yield. -
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Health Expenditure in Puducherry (U.T) A Study using National Health Accounts Framework
With the start of globalization, the Indian economy started experiencing a sudden growth and with the boom of various sector in the economy, the employment opportunity, income as standard of living started increasing. With the increase standard of living, there is an increase in demand for health care services. Health care plays an important role in the lives of the people. With government being welfare oriented every year the investment in health care increases and the private contribution to the health care sector is increasing at a higher pace. This study aims: (1) To quantify the extent of household expenditure on health by household characteristics in Puducherry; (2) To track the flow of resources in Health sector from different sources and present them in the form of accounting principles and (3) To develop a matrice format which facilitates the user to understand the sources of finances and uses of such finances on different item of expenditure. A primary data survey was conducted to capture the picture of household expenditure and the National Health Account matrices framework as prescribed by WHO was used in developing the health accounts matrices. The finding shows that majority of the household expenditure is made in purchasing medicine and other goods from the retail sector. Bulk of the spending is made in curative services. The expenditure flows to retail sale of medicines and drugs seems to be the major provider of services to the community. Households are the prominent sources for spending on health care. Out of the household surveyed only 2 to 3 per cent of the population would opt for health insurance. The present expenditure pattern seems to be shying away from other crucial functional elements of health care like Primary health care, Prevention of diseases, Public health and Promotive care. The study also finds a need to increase the awareness of Health insurance among the public and the need for more investment in health infrastructure as well as training of health personnel. -
Heat amd Mass Transfer Analyses of Nanofluid in a Multilayer Model
The study offers an in-depth exploration into the dynamics and properties of multilayered nanofluids and hybrid nanofluid flow in newlinedifferent geometries. The in-vestigation ranges from sinusoidal channels with micropolar hybrid nanoliquids to concentric cylinders that exhibit electrokinetic effects and rotating disks. Also, the DarcyForchheimer model is introduced to assess non-Newtonian and Newtonian fluid interplay, emphasizing the role of asymmetric slip conditions which reduces the fluid flow. Moreover, the study on bioconvection obtained newlineby addition of gyrotac-tic microorganisms which enhances mass and heat transfer in multilayer Newtonian fluid channels. Studies explain the importance of interfacial regions in achieving optimal system temperature. The subsequent study examines the two-layer hybrid nanofluid (HNF) with magnetohydrodynamic properties between two newlineidentical ro-tating disks. The governing equations of the mathematical models are explained using PDE and solutions are attained using numerical and semi-analytical methods such as the DTM and Range Kutta method. Further, the obtained results have been explained with the help of tables and graphs. The study reveals that the immisci-bility of the base fluids forms an interfacial layer, revealing that the addition of two different fluids restricts the fluid motion nearer to the interfacial region, maintaining an optimum temperature in the system. Collectively, these findings pave the way for advanced applications in industries like solar, nuclear, biomedical, and electronic cooling, promising enhanced newlineperformance and efficiency. -
Heat and Mass Transfer Analysis of Newtonian and Non-Newtonian Nanofluids in The Presence of Motile Microorganisms
This dissertation deals with the analysis of heat and mass transfer in Newtonian and newlinenon-Newtonian nanoand#64258;uid in the presence of motile microorganisms. The major application of the and#64258;uids in heat and mass transfer process is its capability to conduct heat. Hence, the and#64258;uids act as a source that conducts heat and cools down the temperature of the appliance. Whereas, the capacity of heat conductance is low in case of regular and#64258;uids, hence the concept of nanoand#64258;uids was introduced whose thermal conductivity is more when compared to regular and#64258;uids. The high thermal conductivity of nanoparticles helps in conducting more heat and the property of and#64258;uid to and#64258;ow helps the nanoparticles to and#64258;ow all over the desired surface and conduct heat. During the process of nanoand#64258;uid and#64258;ow, the nanoparticles undergo random motion that is termed as Brownian motion and they also experience the thermophoretic force that causes the nanoparticles to move from hotter region to colder region. Further, the presence of nanoparticles would either result in sedimentation or formation a layer of nanoparticles over the surface. This layer of nanoparticles adhered to the surface creates corrosion. Hence, it is important to prevent the nanoparticles from forming its layer over the surface and also the sedimentation of nanoparticles must be avoided to have no blockages in the system. Hence in this regards, self propelled microorganisms newlineare allowed to swim in the nanoand#64258;uid which in turn constitutes bioconvection. Considering these assumptions, problems in this dissertation are modelled such that it deals with the analysis of bioconvection caused due to the swimming of microorganisms in the and#64258;ow newlineof nanoand#64258;uid. The mathematical models of the and#64258;ow, heat and mass transfer of Newtonian and non Newtonian nanoand#64258;uids are designed using the partial differential equations with various assumptions to achieve realistic results. -
HINGLISH IS AN IMPORTANT ADVERTISEMENT APPEAL
Advertising has become very costly and time consuming and is an important marketing activity. A lot of time, energy and money is spent in developing a creative advertising appeals to influence the buying behaviour of consumers through various appeals, advertising influence, rationally or emotionally, the prospects purchase decisions. There are various types of appeals in advertisements. Appeals in both print and broadcast media keep changing according to the innovation and the product that keeps developing in the market. Language is also an important feature of advertisement ad advertisers have experimented a lot in terms of using language be it a particular language likes English or Hindi or au bilingual language. Hinglish is being used by mostly products focussing on youth and rural audience of India and who just does not want to restrict themselves to the elite of the society as the product is affordable. The study would examine the various Hinglish taglines of various different brands. The survey will be done to find out peoples perception about the language Hinglish as an important ad appeal. -
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Humour as a tool for brand recall. Understanding the concept through five star advertisements /
Advertisements are considered as one of the effective tool of promoting a service or product. Though it has high impact on people it uses different appeals to attract the viewers. One of the effective appeals used by advertisers is humour. Humour has been used widely in advertisements since years. Everyone likes humour and the concept behind using humour in advertisements is clearly based on the people’s psychology. The researcher tries to find out whether humour is used as a tool for brand recall or not by using different qualitative and quantitative methods. -
Hybrid Intrusion Detection Technique for Internet of Things
The rapid expansion and integration of Internet of Things (IoT) applications in newlinevarious aspects of daily life has significantly surprised and impacted contemporary society. The most crucial keyword concerning these applications is security, specifically, in the enormous amount of data generated every second, and how it is used. These applications are vulnerable to various attacks, which could result in an unthinkable catastrophe if not managed and controlled with sufficient foresight. Growing concerns about data security in the expanding IoT landscape are driven by factors such as increased vulnerability of devices to viruses, susceptibility to denial-of-service attacks, and heightened risk of intrusion attempts. To prevent such occurrences, stronger precautions should be taken, enabling system developers and manufacturers of IoT devices to enhance their approaches to better security mitigation. It is essential to identify all potential threats and vulnerabilities that are created explicitly for IoT infrastructures. It is believed that to lessen potential dangers, there is a need for more significant research on security attacks. Security difficulties have been found and must be dealt with, so they may be avoided. Further research must address security challenges in IoT-based environments, particularly for suppliers and consumers, to gradually raise the reliability of IoT applications. Although many conventional methods are still used, there might be superior options for devices with limited resources. Artificial intelligence plays a significant role in this issue. newlineThis research first tries to comprehend how machine learning methods relate to attack newlinedetection. The effects of different machine learning techniques are evaluated using the newlineUNSW-NB 15 dataset. Additionally, it has been found that each model performs worse overall, mainly when security issues are present. As a result, real-time datasets and Deep Learning (DL) algorithms for intrusion detection in the IoT need to be prioritized. -
ICT integration in universities in relation to ict challenges and work motivation of lecturers in harare zimbabwe
This study was ICT integration in universities in relation to ICT challenges and work motivation of lecturers in Harare, Zimbabwe. There exists varying rates of ICT newlineintegration in universities and this has a negative impact on the teaching and learning newlineprocesses. The major aim of the study was to assess the relationship between ICT integration, ICT Challenges and work motivation of lecturers. The findings of the study is expected to show how universities could isolate challenges and tailor-make strategies of overcoming them whilst at the same time getting deeper insight into human behavior in an organisation and its contribution towards ICT integration. The thesis was therefore conducted to match availability of ICTs and their utilization as newlinethis had a direct bearing on the curriculum delivery as well as empowering learners to newlineengage in meaningful, challenging and enlightening tasks since ICTs have the potential to play a powerful role in every university- both inside and outside lecture room/classroom. Institutional responses to ICT influences have inevitably brought about a lot of changes in the teaching / learning processes. The research approach adopted was quantitative. The sample included 200 lecturers drawn from a population of 600 lecturers consisting of two private and four state universities. Harare was conveniently chosen as it is the capital city of Zimbabwe and has the greatest number of state and private universities. Two questionnaires one on ICT integration and another one on ICT challenges were designed by the researcher and the third one on Work Motivation Questionnaire was adopted from Agrawal (1988) and standardized for the Zimbabwean context. The major challenges associated with slow newlineuptake were analysed and assessed in terms of their impact on the teaching and learning newlineprocesses and the motivation of lecturers was also evaluated together with demographic newlinefeatures to find predictors of successful ICT integration in universities.