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Synthesis, growth mechanism and physical properties of vapour-deposited GaTe platelets /
Journal Of Applied CrystalloGraphy, Vol.47, Issue 6,pp.1841-1848, ISSN No: 1600-5767. -
Physical properties of vapour grown indium monotelluride platelets /
Journal Of Crystal Growth, Vol.415, pp.81-87, ISSN No: 0022-0248. -
Synthesis, growth mechanism and physical properties of vapour-deposited GaTe platelets
The physical vapour deposition (PVD) method has been employed to yield gallium telluride (GaTe) platelets. The morphology and growth mechanism of these platelets were investigated with the aid of scanning electron micrographs. The stoichiometry and homogeneity of the grown samples were confirmed by chemical analysis. The X-ray diffraction (XRD) technique has been used to explore the structure and phase of the compound. On the basis of the Archimedes principle, the density of crystals was estimated to be 5.442 kg mm-3. The resistivity and conductivity type were determined by the van der Pauw method. UV-vis-NIR studies revealed a direct transition with an energy gap of 1.69 eV. Mechanical properties such as microhardness, toughness, Young's modulus and elastic stiffness constant of GaTe crystals in response to the stress field due to an external load were studied to realize their suitability for radiation detector applications. The present observations provide an insight into the physical properties of the vapour-grown GaTe platelets, which are found to be superior over their melt counterparts. 2014 International Union of Crystallography. -
Physical properties of vapour grown indium monotelluride platelets
Indium monotelluride (InTe) crystals were grown from vapour phase under different temperature gradients by employing physical vapour deposition (PVD) method. The morphology of these crystals such as whiskers, needles, platelets etc., strongly depends on the temperature distribution in the horizontal dual zone furnace. InTe platelets were deposited by setting the temperature of the charge (TC) and growth (TS) zones at 1073 K and 773 K (?T=300 K), respectively, for different growth periods (24 h, 48 h, 72 h and 96 h). The surface growth features have been analyzed by scanning electron microscopes, which indicate layer growth mechanism for all the crystals. Various crystals grown under ?T=200 K and 300 K (retaining TS invariant) were examined by X-ray diffraction and elemental analysis. InTe samples exhibited consistent lattice parameters, density and atomic percentage, establishing stoichiometry and chemical homogeneity. The results obtained for Seebeck coefficient, electrical conductivity, power factor, dislocation density and microhardness are found to be reproducible as well. The vapour deposited InTe platelets are mechanically stable and possess high value of TEP, which ensure their practical application in thermoelectric power generation. 2014 Elsevier B.V. -
Microhardness studies of GaTe whiskers
Single crystal whiskers of gallium telluride (GaTe) have been grown by the physical vapour deposition (PVD) method. Microindentation studies were carried out on the prism faces of the needles to understand their mechanical behaviour. The variation in the microhardnessof GaTe crystals with applied load has been determined at room temperature using Vickers microhardness indenter. The work- hardening exponent has also been computed for different load regions. 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. -
Dislocation and microindentation analysis of vapour grown Bi 2Te3-xSex whiskers
The structural defects and microhardness of Bi2Te 3-xSex whiskers (x = 0, 0.2 and 0.4 at % Se) grown by physical vapour deposition (PVD) method have been investigated. Concentric pairs of dislocation loops were observed on the as-grown surfaces of short hexagonal prisms. A systematic study of dislocations in these crystals was carried out by chemical etching technique. The effects of Se doping, annealing and quenching on the mechanical properties have also been studied on the prism faces of Bi 2Te3-xSex whiskers. 2008 WILEY-VCH Verlag GmbH & Co. KGaA. -
Effect of supercooling on the microstructural development and optimization of physical properties of melt grown SnSe crystals
The microstructural development of stoichiometric tin monoselenide (SnSe) crystals grown by vertical BridgmanStockbarger method using an indigenously fabricated furnace has been investigated under high vacuum (~ 10?6 mbar). The ampoule translation rate (tr) and supercooling, ?T (= Tm ? T, where Tm is the melting point and T is the crystallization temperature) were varied in the range, 122mm/h and 20100C respectively. Enhancement of ?T and tr led to constitutional supercooling, inducing compositional changes and non-stoichiometry. Low ?T (2040C) and high tr (1210mm/h) resulted in globules, flakes and cavities. When ?T = 60C and tr = 9 to 7mm/h, mounds were formed with closed contours and ripples, due to atomically rough liquidsolid (l-?) interface. Fine tuning of ?T (60C) and tr (2mm/h) enabled smooth planar interface, so as to yield good quality crystalline structures with periodic atomic deposition promoting crystal growth, layer-by-layer. Energy dispersive analysis by X-rays and powder X-ray diffraction studies revealed appreciable crystallinity, chemical homogeneity and phase purity. The density of crystals estimated from crystallographic data (6.183g/cm3) corroborates with that obtained utilizing Archimedes principle. Thermogravimetric and microindentation analyses established thermal and mechanical stability. The low etch pit density (~ 102 cm?2) manifests nearly perfect growth of crystals than their melt counterparts. UVVisNIR and PL spectra reflected direct transition with an energy gap of 1.32eV, validating immense potential of the grown crystals for photovoltaic applications. 2019, Springer Science+Business Media, LLC, part of Springer Nature. -
Planetary Ball Milling and Tailoring of the Optoelectronic Properties of Monophase SnSe Nanoparticles
Downscaling of tin monoselenide (SnSe) samples to the nanometer regime (~8020nm) without affecting the structure, homogeneity, and optoelectronic properties was carried out by high-energy planetary ball milling (BM). The milling rate was varied from 200rpm to 800rpm by adopting a dry and wet-grinding top-down approach on customized stoichiometric SnSe precursors. The degree of crystallinity was assessed by powder x-ray diffraction (PXRD) and selected area electron diffraction. The lattice parameters, a = 4.435 b = 11.498 and c = 4.148 of the nanoparticles were calculated from the PXRD data. Energy-dispersive x-ray analysis confirmed the chemical homogeneity (49.88:51.12 at.%) of the samples. The effects of rotational velocity as well as mode of grinding on the morphology and the size of SnSe powders were investigated using electron microscopes. The direct optical transition with band gap varied from 1.75eV to 2.28eV was elucidated from UV-Vis-NIR data. Photoluminescence revealed an increase in the intensity of the emission peak at 462.97nm with angular velocities for both types of grinding. The variation of electrical resistivity (36107 ? cm) and mobility (3.451.12 cm2/Vs) with rotational speed was calculated for all the samples. The results obtained for the ball-milled nanoparticles pave the way towards the reduction of particle size, formation of stable morphology, and appreciable crystalline structure quality suitable for solar cell absorbers. Graphical Abstract: [Figure not available: see fulltext.] 2023, The Minerals, Metals & Materials Society. -
Transport Vehicle Demand Prediction Using Context-Aware Neural Networks
Transport is an important aspect of trade. The more efficient the transport system, the more trade will flourish. However, sometimes it is the case that vehicles are not available for transport. This necessitates a system which could be able to keep an eye on the demand of transport vehicles. If the demand is fulfilled properly, then trade will flourish in a much better way. Thus, this project aims to keep an eye on the demand of transport vehicles and fulfill it. The study used MLP and LSTM models to work. The project also shows a comparison between the gradual changes and improvements in MLP and LSTM and the type of data used. The study focus was to predict the demand accurately in an area. 2024 by the authors. Licensee MDPI, Basel, Switzerland. -
The aesthetics of corpses in popular culture
[No abstract available] -
A CRITICAL STUDY IN UNDERSTANDING THE POTENTIAL BENEFITS OF IMPLEMENTING DIGITAL FINANCIAL APPLICATION IN ENHANCING THE ACCOUNTING PERFORMANCE IN ORGANISATIONS
Failure to innovate in this era of rapid IT growth is a significant obstacle to the modernization and growth of industries and increases the competitiveness of such organizations in the market. Strong innovation and competence are more than necessary to turn innovative ideas into reality, gain new competitive advantages and achieve sustainable long-term growth. Innovation is not only an important tool for companies to increase their competitiveness, it is also an important driver of long-term economic growth for a country. Regular engagement in high-quality innovation activities should be mandatory for organizations that intend to successfully adapt to today's fast-paced digital economy. If companies want to improve their chances of survival in the coming years and continue to grow, they need to invest in their innovation capabilities. Many companies now operate under the assumption that updating their accounting systems with advanced software will provide better results than relying on old, time-honored methods. Concrete steps are needed, such as developing powerful data-driven tools to improve how individuals, organizations and governments spend their money. Beginners still have to put in the effort to learn new skills because they often have trouble imagining using a device they've never used before to accomplish a task. Due to the increased automation of this financial system, the risk of error has increased; So it is very important. In fact, you can manage your needs exactly with this tool. 2024 Published by Faculty of Engineering. -
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Effects of central bank intervention through quasi fiscal policies evidence from reserve bank of zimbabwe
This was a research exercise which was conducted to establish the impact of newlineZimbabwe s Central Bank s interventions on the economy. As Zimbabwe s economic newlinecondition went through a nose-dive, the government found itself unable to respond to newlinethe numerous needs with no resources. The country was achieving negative gross domestic product (GDP) growth rate every year since the turn of the new millennium. The country could not borrow from the Bretton Woods institutions such as the International Monetary Fund (IMF) because of the illegal sanctions imposed by the United States and European Union following the country s land reform program which acquired farms from the majority of the 4,000 white farmers who owned about 80 percent of the country s arable area. The Zimbabwe Economic and Democracy newlineRecovery Act of 2001 (ZEDERA), enacted in the USA prevented American companies from doing business in Zimbabwe. The Reserve Bank of Zimbabwe stepped in to assist. The research was aimed at establishing the effect the central bank intervention on the economy. Was the effect of the intervention good, or bad? Did the central bank s intervention really make things worse or did it ameliorate the effects of the downturn in the economy? For newlineinstance, did it contribute to the increase in inflation? What would have been the newlinesituation had the Bank not intervened? This study sought to answer the basic question: newline What was the overall impact of the RBZ s quasi-fiscal activities on the Zimbabwean newlineeconomy? Hypotheses were formulated on the basis of the above objectives and were tested newlinevia a variety of statistical techniques. The research instruments for data collection newlinewere a questionnaire and interviews guides. The questionnaire was the main research newlineinstrument followed by interviews. The questionnaire had a fusion of open ended and newlineclosed questions. The research showed that the RBZ s quasi-fiscal operations helped newlinethe country most in containing emergency situations and improved access to financial newlineresources by the productive sectors. -
Enhanced Light Scattering Using a Two-Dimensional Quasicrystal-Decorated 3D-Printed Nature-Inspired Bio-photonic Architecture
A number of strategies have been exploited so far to trap photons inside living cells to obtain high-contrast imaging. Also, launching light inside biological materials is technically challenging. Using photon confinement in a three-dimensional (3D)-printed biomimetic architecture in the presence of a localized surface plasmon resonance (LSPR) promoter can overcome some of these issues. This work compares optical confinement in natural and 3D-printed photonic architectures, namely, fish scale, in the presence of atomically thin Al70Co10Fe5Ni10Cu5 quasicrystals (QCs). Due to their wideband LSPR response, the QCs work as photon scattering hotspots. The architecture acts as an additive source of excitation for the two-dimensional (2D) QCs via total internal reflection (TIR). The computational analysis describes the surface plasmon-based scattering property of 2D QCs. The 3D-printed fish scale's image contrast with the 2D Al70Co10Fe5Ni10Cu5 QC has been compared with other 2D materials (graphene, h-BN, and MoS2) and outperforms them. The present study conceptually presents a new approach for obtaining high-quality imaging of biological imaging, even using high-energy photons. 2023 American Chemical Society. -
Spontaneous hydrogen production using gadolinium telluride
Developing materials for controlled hydrogen production through water splitting is one of the most promising ways to meet current energy demand. Here, we demonstrate spontaneous and green production of hydrogen at high evolution rate using gadolinium telluride (GdTe) under ambient conditions. The spent materials can be reused after melting, which regain the original activity of the pristine sample. The phase formation and reusability are supported by the thermodynamics calculations. The theoretical calculation reveals ultralow activation energy for hydrogen production using GdTe caused by charge transfer from Te to Gd. Production of highly pure and instantaneous hydrogen by GdTe could accelerate green and sustainable energy conversion technologies. 2023 -
Plasmonic Nanocomposite for Visible Light-Modulated Bimorph-Actuator
Soft actuators have great potential applications in sophisticated movement and sensitive devices due to their flexible nature, good interaction, and precise control. However, existing carbon-based optical actuators are limited in their response under visible light irradiation. The limited visible light absorbance of the carbon nanostructure brought the metallic nanoparticle into the soft actuators that can absorb visible light. This study introduces a new type of plasmonic photothermal-bimorph actuator, using graphene oxide (GO), reduced graphene oxide (rGO), and silver nanorods (Ag NRs) to overcome the limitations of traditional optical actuators. The bimorph film is actuated by visible and near-infrared light stimuli with various power densities showing reversible deformation behavior. The actuator shows significant bending associated with a ?50 change in bending angle under visible light irradiation with a response time of ?5 1 sec. Furthermore, a smart photo-controlled non-contact switch is fabricated based on photo-thermal conversion properties, demonstrating perfect integration of plasmonic bimorph actuators. The density functional theory based molecular dynamics calculations provide an additional understanding of the bending of actuators under external stimulus. Using illustrative demonstrations of actuators, these results hint at a method for generating multipurpose visible light-based soft robots, supporting a new approach to developing an optical locking system. 2024 Wiley-VCH GmbH. -
2D Materials Coated Flexible Origami for Low-Frequency Energy Harvesting
Wave energy is one of the most abundant energy sources. Triboelectric nanogenerators (TENGs) are becoming more popular for sustainable energy generation from waves. Concerning the renewable energy demands, we focus on developing cost-effective and adaptable origami-TENGs (O-TENGs) for harvesting wave energy, specifically utilizing paper-based (cellulose) materials. An origami-inspired lightweight and scalable design is proposed to create high-performance O-TENGs suitable for the complex conditions of low-frequency wave excitation. The paper-based spring-like O-TENG is coated with two-dimensional (2D) molybdenum disulfide (MoS2) nanosheets and demonstrates efficacy in harvesting mechanical energy in the ambient environment and the output performance compared with reduced graphene oxides (rGO). A detailed density functional theory (DFT) calculation was used to analyze the charge transfer mechanism in the coated origami structures. Furthermore, a barrel-shaped floating generator incorporating multiple origami TENGs is introduced to capture ocean wave energy across various frequencies, amplitudes, and directional movements. Since the coated origami structures show a good self-rebounding spring-like nature and energy harvesting properties, they are suitable for blue energy harvesting. 2025 American Chemical Society. -
Strain-Induced Tribocatalytic Activity of 2D ZnO Quantum Dots
The use of low-frequency vibration or high-frequency ultrasound waves to create polarization and an inherent electric field in piezo-tribocatalysts has recently been shown to be a novel advanced oxidation process. In this study, we have demonstrated the synthesis of two-dimensional (2D) ZnO quantum dots (QDs) and their strain-induced tribocatalytic effect, where the triboelectric charges generated under the influence of friction and strain are used to facilitate the decomposition of organic dye molecules. The catalytic performance of 2D QD catalysts can be tuned by modulation of the strain-induced band-gap variation, which are typically regarded as the active sites. The underlying mechanism for the strain-induced catalytic performance is due to the presence of defective dipole moments. Detailed theoretical investigations reveal strain-induced charge-transfer-dependent catalytic properties of the 2D ZnO QD-polymer interface. We believe that the present work provides a fundamental understanding of the design of high-performance catalysis applications for water cleaning and emerging technologies. 2024 American Chemical Society. -
Prospective applications of two-dimensional materials beyond laboratory frontiers: A review
The development of nanotechnology has been advancing for decades and gained acceleration in the 21st century. Two-dimensional (2D) materials are widely available, giving them a wide range of material platforms for technological study and the advancement of atomic-level applications. The design and application of 2D materials are discussed in this review. In order to evaluate the performance of 2D materials, which might lead to greater applications benefiting the electrical and electronics sectors as well as society, the future paradigm of 2D materials needs to be visualized. The development of 2D hybrid materials with better characteristics that will help industry and society at large is anticipated to result from intensive research in 2D materials. This enhanced evaluation might open new opportunities for the synthesis of 2D materials and the creation of devices that are more effective than traditional ones in various sectors of application. 2023 The Authors -
Energy Harvesting Using ZnO Nanosheet-Decorated 3D-Printed Fabrics
In this work, we decorated piezoresponsive atomically thin ZnO nanosheets on a polymer surface using additive manufacturing (three-dimensional (3D) printing) technology to demonstrate electrical-mechanical coupling phenomena. The output voltage response of the 3D-printed architecture was regulated by varying the external mechanical pressures. Additionally, we have shown energy generation by placing the 3D-printed fabric on the padded shoulder strap of a bag with a load ranging from ?5 to ?75 N, taking advantage of the excellent mechanical strength and flexibility of the coated 3D-printed architecture. The ZnO coating layer forms a stable interface between ZnO nanosheets and the fabric, as confirmed by combining density functional theory (DFT) and electrical measurements. This effectively improves the output performance of the 3D-printed fabric by enhancing the charge transfer at the interface. Therefore, the present work can be used to build a new infrastructure for next-generation energy harvesters capable of carrying out several structural and functional responsibilities. 2023 American Chemical Society.