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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 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 glycine potassium nitrate NLO crystals
Single crystals of glycine potassium nitrate were grown using slow evaporation technique. The solutions were prepared mixing glycine with potassium nitrate in different ratios stirring continuously for an hour to get a saturated solution. It was then kept at room temperature for controlled evaporation. Optically clear and well shaped crystals were obtained and these were characterized by (FTIR) studies, EDAX and X-ray powder diffraction. 2011 American Institute of Physics. -
Growth and characterization of chalcogenide crystals by vapour method
A horizontal linear gradient two zone furnace was designed and employed to grow single crystals of indium telluride by Physical Vapour Deposition (PVD) method. It was calibrated for various trials including, series and parallel combinations of coils, and set temperatures. Systematic growth runs for chalcogenide crystals were performed by varying the source and growth temperatures. Crystals of different sizes and morphologies were obtained. The morphology and chemical analysis of the grown crystals were investigated by Scanning Electron Microscope (SEM) and Energy Dispersive Analysis using X-rays (EDAX). The hardness of the crystals was estimated using a Vickers microhardness tester. 2011 American Institute of Physics. -
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. -
Group signature based security technique for privacy identity information protection in blockchain /
Patent Number: 202121031204, Applicant: Gauri Arun Varade.
On cryptographic algorithms blockchain is a highlight point dispersed record innovation dependent. By factual techniques, information mining and sociological mining has made clients protection face significant dangers the straightforward and open blockchain record enhanced. -
Group signature based security technique for privacy identity information protection in blockchain /
Patent Number: 202121031204, Applicant: Gauri Arun Varade.
On cryptographic algorithms blockchain is a highlight point dispersed record innovation dependent. By factual techniques, information mining and sociological mining has made clients protection face significant dangers the straightforward and open
blockchain record enhanced. -
Group Movie Recommendations via Content Based Feature Preferences
International Journal of Scientific & Engineering Research Vol. 4, Issue 2, pp.1-5 ISSN No. 2229-5518 -
Group Key Management Techniques forSecure Load Balanced Routing Model
Remote sensor organizations (WSNs) assume a vital part in giving ongoing information admittance to IoT applications. Be that as it may, open organization, energy limitation, and absence of brought together organization make WSNs entirely defenseless against different sorts of pernicious assaults. In WSNs, recognizing vindictive sensor gadgets and dispensing with their detected data assume a vital part for strategic applications. Standard cryptography and confirmation plans cannot be straightforwardly utilized in WSNs on account of the asset imperative nature of sensor gadgets. In this manner, energy productive and low idleness procedure is needed for limiting the effect of malignant sensor gadgets. In this research work presents a secured and burden balanced controlling contrive for heterogeneous bunch-based WSNs. SLBR shows a predominant trust-based security metric that beats the issue when sensors proceed to influence from extraordinary to terrible state and the other way around; besides, SLBR alters stack among CH. In this way, underpins fulfilling superior security, allocate transmission, and vitality efficiency execution. Trials are driven to calculate this presentation of developed SLBR demonstrate over existing trust-based controlling show, particularly ECSO. The result accomplished appears SLBR demonstrate fulfills favored execution over ECSO as distant as vitality capability (i.e., arrange lifetime considering to begin with sensor contraption downfall and total sensor contraption passing), correspondence overhead, throughput, allocate planning idleness, and harmful sensor contraption mis-classification rate and recognizable verification. 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. -
Ground Truncated Broadband Slotted Circular Microstrip Antenna
In this growing era of wireless technology, large sized devices have become obsolete. In response to the increasing demand for miniaturization over the past decades, microstrip antennas have drawn attention due to its various features like light weight, low cost, small in size and its greater resistivity to shock and vibrations. These can also easily get conformed to any surface. These antennas are also capable of operating at high frequencies, providing large bandwidth and gain by using various techniques slots and truncation of shapes. This report describes the design, simulation, fabrication and measurement results of a microstrip fed Slotted Circular Microstrip Antenna for broadband applications. The antenna was designed for an operating frequency of 2.45 GHz on a double side printed FR4 substrate measuring 55 mm x 55 mm x 1.6 mm with ?r of 4.4. It measured a very large resonant band of 1.3 - 9.05 GHz at a return loss level as low as -36.5 dB at 7.98 GHz. A maximum gain of 2.46 dB was achieved at 2.33 GHz. The enhancement in bandwidth was achieved by truncation in ground and inclusion of thin circular slot. The HFSS version 18.2 software and VNA model Anritsu SA20E were used for simulation and measurement respectively. It is found that the simulation and measurement results agree. 2018 IEEE. -
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Grip-on: The ergonomic walking stick /
Patent Number: 202241053663, Applicant: Joel Sebastian.
A high percentage of elderly users depend on walking slicks to get better support or assistance in maintaining a good posture while walking. An ergonomically well-designed walking stick can only provide good postural stability. For the past few decades in India, no significant changes or innovations have been made to the conventional walking stick. The study identified that majority of the users are facing difficulty in handling these conventional walking sticks. -
Grey Wolf optimization-Elman neural network model for stock price prediction
Over the past two decades, assessing future price of stock market has been a very active area of research in financial world. Stock price always fluctuates due to many variables. Thus, an accurate prediction of stock price can be considered as a tough task. This study intends to design an efficient model for predicting future price of stock market using technical indicators derived from historical data and natural inspired algorithm. The model adopts Elman neural network (ENN) because of its ability to memorize the past information, which is suitable for solving stock problems. Trial and error-based method is widely used to determine the parameters of ENN. It is a time-consuming task. To address such an issue, this study employs Grey Wolf optimization (GWO) algorithm to optimize the parameters of ENN. Optimized ENN is utilized to predict the future price of stock data in 1day advance. To evaluate the prediction efficiency, proposed model is tested on NYSE and NASDAQ stock data. The efficacy of the proposed model is compared with other benchmark models such as FPA-ELM, PSO-MLP, PSOElman,CSO-ARMA and GA-LSTM to prove its superiority. Results demonstrated that the GWO-ENN model provides accurate prediction for 1day ahead prediction and outperforms the benchmark models taken for comparison. 2020, Springer-Verlag GmbH Germany, part of Springer Nature. -
Grey Wolf Optimization Guided Non-Local Means Denoising for Localizing and Extracting Bone Regions from X-Ray Images
The key focus of the current study is implementation of an automated semantic segmentation model to localize and extract bone regions from digital X-ray images. Methods: The proposed segmentation framework uses a pre-processing stage which follows convolutional neural network (CNN) obtained segmentation stage to extract the bone region from X-ray images, mainly for diagnosing critical conditions such as osteoporosis. Since the presence of noise is critical in image analysis, the X-ray images are initially processed with a grey wolf optimization (GWO) guided non-local means (NLM) denoising. The segmentation stage uses a Multi-Res U-Net architecture with attention modules. Findings: The proposed methodology shows superior results while segmenting bone regions from real X-ray images. The experiments include an ablation study that substantiates the need for the proposed denoising approach. Several standard segmentation benchmarks such as precision, recall, Dice-score, specificity, Intersection over Union (IOU), and total accuracy have been used for a comprehensive study. The proposed architectural has good impact compared to the state-of-the-art bone segmentation models and is compared both quantitatively and qualitatively. Novelty: The denoising using GWO-NLM adaptively chose the denoising parameters based on the required conditions and can be reused in other medical image analysis domains with minimal finetuning. The design of the proposed CNN model also aims at better performance on the target datasets. 2023 Biomedical & Pharmacology Journal. -
Greenpreneurship pioneering solutions for climate change: An Indian perspective
In an era marked by pressing global climate challenges, the role of green entrepreneurship, or "greenpreneurship, " has gained paramount significance. The present chapter begins by elucidating the inherent connection between greenpreneurship and climate change, followed the contributions of the greenpreneurs appreciating their efforts to make a difference to the society. The chapter mentions certain skills and traits required by greenpreneurs to run their business. It states the challenges that the greenpreneurs face. The chapter then takes a dive into the realm of greenpreneurship from an Indian perspective. India, with its unique blend of environmental challenges and a burgeoning entrepreneurial ecosystem, presents an intriguing case study. The chapter illustrates how Indian greenpreneurs are contributing to a cleaner, greener future. It states the policies which the government has made to support greenpreneurs in the country. Finally, recommendations are given for existing greenpreneurs, budding entrepreneurs, the public, and the government to collectively drive green solutions. 2024, IGI Global. All rights reserved. -
Greener Assembly of Nano Catalysts and Sustainable Applications of Magnetically Retrievable and Plasmonic Nano Catalysts
Since ages, catalysts have played a pivotal role in accelerating the production and lowering the cost of a plethora of industrially important commodities. The latest in the scenario are nanocatalysts, which offer a wide array of advantages ranging from improved reaction rates to higher rates of recyclability. However, factors such as stability and support systems must be fine-tuned to achieve maximum efficiency. In accordance with the principle of sustainability, green synthesis methods have propelled the development of a range of nanocatalysts that can be applied in various domains, such as the food industry and biofuel production. Simultaneously, heterogeneous catalysis is gaining more attention globally, primarily due to the ease of recoverability of the nanocatalysts and in this context, magnetically retrievable nanocatalysts are indeed a boon for the green synthesis and sustainable production. Nanocomposites combining plasmonic and catalytic components with noble metal nanoparticles (Au and Ag) and doped semiconductor nanostructures have gained interest in recent years owing to their utility in multiple sectors by virtue of their ability to convert sunlight to chemical energy. The current review describes some methods for the synthesis of such nanocatalysts and their applications in diverse domains. Graphical Abstract: (Figure presented.) The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023. -
Green-Synthesized Sm3+-Doped ZnO Nanoparticles for Multifunctional Applications
The present study focuses on the green-mediated synthesis of pristine and Sm3+-doped ZnO nanoparticles using Syzygium cumini fruit extract. The prepared material was characterized by various characterization techniques. Photocatalytic degradation of a fast orange red (FOR) dye under UV light resulted in 88% degradation, with a minimal decrease (87.90%) observed even after five successive runs, indicating the stability and effectiveness of the catalyst. The enhancement in degradation efficiency is attributed to the incorporation of Sm3+ ions into the ZnO lattice. Utilizing the optimized Sm3+ (5 mol%)-doped ZnO nanoparticles, cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) were performed on the prepared electrode, demonstrating the excellent CV properties; this enhancement is attributed to the modification of ZnO's redox chemistry and the alteration of charge transfer kinetics at the electrode-electrolyte interface due to the addition of Sm3+ into the ZnO structure. The antibacterial activity was performed against two pathogenic strains, i.e., Escherichia coli and Streptococcus aureus. The obtained results suggest that the prepared material holds great promise for catalytic, energy storage, antibacterial, and other multifunctional applications. 2024 Lavanya R. et al. -
Green-synthesized nanoparticles and their therapeutic applications: A review
Antibiotic-resistant microorganisms are a rising issue when it comes to human health. Microbial pathogens that cause harmful infections are quickly becoming resistant to the antimicrobial action of traditional antibiotics. Nanotechnology, an innovative sector being an indispensable part of healthcare and research, has in-depth and extensive applications. Nano-compounds have been promising antimicrobial agents, anti-cancerous mediators, vehicles for drug delivery, formulations for functional foods, identification of pathogens, food and drug packaging industry, and many more. However, the chemical synthesis of nanoparticles (NPs) has certain drawbacks such as causing toxicity and other adverse effects. For more than a decade, the use of NPs that are conjugated or green-synthesized has gained popularity due to the two-fold action of metallic NPs mixed with biological sources. In contrast, NPs synthesized using plant or microbial extracts, conjugated with biologically active components, appear to be a safe alternative approach as they are environmentally friendly and cost-effective. Such environmentally safe techniques are referred to as "green nanotechnology"or "clean technology"and are feasible alternatives to chemical methods. Furthermore, NPs conjugated with natural biomolecules have improved bioavailability and have minimal side effects, as they are smaller in size and have higher permeability in addition to being reducing and stabilizing agents possessing excellent antioxidant activity. NPs serve as potential antimicrobial agents due to their affinity towards sulphur-rich amino acids, adhere to microbial cell walls by means of electrostatic attraction, and disrupt the cytoplasmic membrane along with the nucleic acid of microbes. They possess anticancer activity owing to oxidative stress, damage to cellular DNA, and lipid peroxidation. The green-synthesized NPs are thus a promising and safe alternative for healthcare therapeutic applications. 2023 the author(s), published by De Gruyter. -
Green Synthesized ZnO Nanoparticles as Biodiesel Blends and their Effect on the Performance and Emission of Greenhouse Gases
Pollution and global warming are a few of the many reasons for environmental problems, due to industrial wastes and greenhouse gases, hence there are efforts to bring down such emissions to reduce pollution and combat global warming. In the present study, zinc oxide nanoparticles are green synthesized using cow dung as fuel, through combustion. Synthesized material was characterized by FTIR, XRD, UV, and FESEM. The as-prepared ZnO-GS NPs were employed as a transesterification catalyst for the preparation of biodiesel from discarded cooking oil. The biodiesel obtained is termed D-COME (discarded cooking oil methyl ester), which is blended with 20% commercial diesel (B20). Additionally, this blend, i.e., B20, is further blended with varying amounts of as-prepared ZnO-GS NPs, in order to ascertain its effects on the quality of emissions of various greenhouse gases such as hydrocarbons, COx, NOx. Moreover, the brake thermal efficiency (BTHE) and brake specific fuel consumption (BSFC) were studied for their blends. The blend (B20) with 30 mg of ZnO-GS, i.e., B20-30, displays the best performance and reduced emissions. Comparative studies revealed that the ZnO-GS NPs are as efficient as the ZnO-C NPs, indicating that the green synthetic approach employed does not affect the efficiency of the ZnO NPs. 2022 by the authors. Licensee MDPI, Basel, Switzerland.