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Effect of electroplating time on microstructure, corrosion and wear behaviour of Ni-P-W-TiO2 coating
Get PDFNi-P-W-TiO2 coating has been deposited on the AISI 304L steel substrate using the electroplating method. Electroplating has been performed at 30, 45, and 60 min, and the effect of electroplating time on microstructure, corrosion and wear behaviour has been investigated. The coatings have been characterized by use of scanning electron microscopy (SEM). In order to investigate corrosion resistance, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests have been used in 3.5% of NaCl aqueous solution. A pin on disk test has been used to test the wear resistance of uncoated and coated samples. Sample micro-hardness has also been measured by the Vickers hardness test. Examination of the microstructure has shown that the best time for deposition is 45 min. The results of potentiodynamic polarization and electrochemical impedance spectroscopy tests are also consistent with microscopic images, and the results have shown that the coating created within 45 min has the highest corrosion resistance (7058 Ω.cm2) compared to coated sample within 30 (4142 Ω.cm2) and 60 (3059 Ω.cm2) minutes. Also, the results of the wear test and micro-hardness have shown that composite coating formed within 45 minutes has the highest wear resistance and micro-hardness (677 Vickers) compared to coated sample within 30 (257 Vickers) and 60 (638 Vickers) minutes
Green carbon dots from poppy seeds with conjugated hydrogel hybrid films for detection of Fe3+
Get PDFA simple, non-toxic and eco-friendly method has been developed for detection of Fe3+ using the beneficial plant Opium Poppy (Papaver somniferum) seeds as a carbon source to fabricate a hybrid film (HF). The hybrid film platform comprises of quince seed mucilage and sodium alginate to form a fluorescent hybrid film with green carbon dots derived from poppy seeds (P-CDs). All materials and methods contain non-toxic chemicals. The prepared samples have been characterized morphologically, structurally and optically by spectroscopic techniques. A hydrodynamic radius of the P-CDs is determined as an average of 4.79 nm using Dynamic Light Scattering (DLS). It has been identified that hybrid film is selective towards Fe3+ ions among different metal ions with one-step by the naked-eye and turn-off detection and selectivity of P-CDs to Fe3+ is determined by fluorescence measurement. The detection limit (LOD) of Fe3+ ion is found as 0.356 mM. Developments of such a hybrid material from sustainable and low-cost sources make it an interesting option as a detection material must be investigated in various fields. For the first time, quince seed mucilage combined with green carbon dots and it has been studied in the detection field as a hybrid film. This study has proven that biotechnological studies about carbon dots can also obtain efficient results by providing green, economic, energy and water saving approaches
Optimization and Analysis of Wireless Networks Lifetime using Soft Computing for Industrial Applications
Get PDFRecently, wireless networks are applied in various engineering and industrial applications. One of the critical problems in wireless network system optimization in intelligent applications is obtaining an adequate energy fairness level. This issue can be resolved by applying effective cluster-based routing optimization with multi-hop routing. Hence a new network structure is developed that is derived from energy consumption architecture by applying soft computing strategies such as evolutionary operators in determining the exact clusters for optimizing energy consumption. The new effective evolutionary operators are tested in the optimization of a lifetime. The proposed method is simulated for different values of the routing factor, α, for different types of networks. The energy levels range from 0.4 to 0.8, achieving good results for nearly 2500 rounds. The proposed strategy optimizes the clusters, and its head is selected reliably. The optimization of cluster head choice has been done based on the base station distance, the energy of the node, and the node's energy efficiency. The reliability of the long-distance nodes is increased during the data transmission by modifying the size of the area of the candidate set of nodes in contrast the near-distance node's energy consumption is reduced. For the energy levels that range from 0.4 to 0.8, the higher network throughput is obtained at the same time network lifetime is optimized compared to other well-known approaches. The proposed model is expected for different industrial wireless network applications to optimize the systems during the long-run simulation and to achieve high reliability and sustainability
Crystal structure of dimethyl ammonium 5-(2, 4-dinitrophenyl)-1,3-dimethyl barbiturate
Get PDFThe titled molecular salt dimethyl ammonium 5-(2,4-dinitrophenyl)-1,3-dimethyl barbiturate has been prepared from the ethanolic solution of 1-chloro-2,4-dinitrobenzene, 1,3-dimethylbarbituric acid and dimethyl amine. FT-IR, 1H-NMR, 13C-NMR, and single crystal diffraction results support the proposed structure of the compound. The crystal structure of the titled complex [monoclinic, space group p21/n, a=11.5729 (15)Å, b=8.6857(11) Å, c=16.701(2) Å, Z=4] are analyzed by single-crystal X-ray diffraction. In this crystal, intermolecular N-H…O and C-H…O hydrogen bonds forming a three dimensional network and small red spot in Hirshfeld surfaces indicates the presence of C-H...π interactions
Optimisation of Diffusion Welding Parametersin Al-Cu Bimetal for Shaped Charge Application
Get PDFOptimum process parameters (temperature, pressure, and time) for diffusion welding of aluminium and copper have been achieved with better shear strength for application in shaped charges using the Taguchi method. The study involved characterising the type and thickness of intermetallic compounds formed at the faying surfaces using optical microscopy, scanning electron microscopy and electron probe micro analyser, lap shear strength assessment, microhardness, and X-ray diffraction. It is confirmed that intermetallic compounds of type Al4Cu (σ), Al2Cu (θ), and AlCu (η1) with traces of Al2Cu3 (δ) and AlCu4 (α2) were formed at the interface. The optimum shear strength of 42.2 N was achieved with diffusion welding at temperature 510oC, pressure 0.5 MPa and time 5400 s. By diffusion welding at these conditions, the shape charge cones fabricated and explosively filled such shaped charges paved, an increase of 0.42 times in the penetration of target with diffusion welded copper-aluminium shape charge cones compared with that from conventional monolithic copper sheet
Optimization on Manufacturing Processes at Indian Industries Using TOPSIS
Get PDFEvaluation and optimization of multi-criteria with multiple alternatives have been essential activities for decision-making process. TOPSIS (Technique for order of preference by similarity to ideal solution), a multi-criteria decision-making (MCDM) technique, has been adopted in the past for research & decision-making and ranking of alternatives by optimizing input parameters to get the maximum overall output from the system. This study aims to explore the context, reasons, and particular advantages of using TOPSIS in the materials science and engineering field for realizing goals of competitive supply chains (SCs). This study has reviewed and analyzed research papers from the approach of systematic review of the literature. This study has presented a conceptual framework to emphasize the antecedents and consequences of using the TOPSIS methodology for output optimization in the materials science and engineering industry that can improve the competitiveness of SCs. This study found that TOPSIS based methodologies have been used in eleven types of industries in India, indicating the prowess of TOPSIS methodology. The results of TOPSIS have compared very well with other MCDM methods that are relatively more difficult and cumbersome. This study will help the engineers, practitioners, academicians, researchers, and SC managers with the application approach of TOPSIS for output optimization in various fields
Mapping the Geography of Sustainability Transitions Research: A Bibliometric Analysis
Get PDFThe transition towards sustainability is a global challenge, and in recent decades, Sustainability Transitions (ST) research has emerged as a promising approach to address climate change-led uncertainty. Despite the rapid rise in the sustainability transitions literature, it is primarily focused on developed or global north countries. The present paper attempts to use bibliometric tools to comprehend the intellectual landscape and distribution between global north-south and analyse the trends and hotspots in global south countries. The paper comprehensively examined ST literature on the Scopus citation database (from the inception of ST in 1994 to December 31, 2020). Based on statistical analysis performed on the dataset, there has been an exponential rise in research publications on ST since 2012. Globally, ST researchers mainly belong to OECD countries from Western Europe, especially in the UK, Netherlands and Germany. Conversely, the global south is lagging, except few developing nations such as China, South Africa, Brazil, and India. This skewed representation reflects the higher prevalence of ST initiatives in the global north, predominantly by a few European countries. About 40% of ST research is published in journals from the UK, Netherlands, the U.S., Switzerland and Canada. The citation analysis reflects that 60% of citations are from British and Dutch scholars, indicating a low academic influence of ST authors from developing countries. This study would stimulate more interest among Global South academics and policy researchers to put more effort into ST research and publication to bridge the existing gap
Investigation of Physicochemical, Mechanical, Thermal and Rheological Properties of Mrigbahar Nagpur Mandarin (Citrus reticulate Blanco.)
Get PDFNagpur mandarin (popularly known as Nagpur Santra) is an indigenous fruit with high nutritional and functional value. It is the only cultivar of mandarin grown in Vidarbha region of Maharashtra. As per harvesting time they are ambiabahar (Ocrober-November) and mrigbahar (February-March). Out of these two, mrigbahar is unique to Nagpur and of superior quality, hence taken for the study. The physicochemical, thermal, mechanical, rheological and textural properties of mrigbahar Nagpur mandarin are studied in this work. The sphericity (0.90) of mrigbahar fruit is considered to be spherical. The mean breadth, thickness and length of the fruit are 54.9, 47.3 and 57.9 mm, respectively. The true density, porosity and bulk density are 1.364 g/m3, 65.10% and 0.517 g/m3. The thermal conductivity, thermal diffusivity and specific heat of Nagpur mandarin fruit are 0.588 W/m℃, 11.84 × 10−2 m2/s and 3.909 kJ/kg℃. Under rheological properties of Nagpur mandarin juice, it is observed that as the shear rate increased, viscosity (ƞ) and shear stress (σ) decreased and Herschel Bulkley model is most suitable to characterise flow behaviour. The textural properties reveal that fracturability with 1% load sensitivity is 10.27 N with respective values of stringiness length (4.04 mm). The findings of this investigation would help for the post-harvest handling, processing equipment and value-added products from Nagpur mandarin
Transforming Imagined Thoughts into Speech Using a Covariance-Based Subset Selection Method
Get PDFWith the advancement of engineering solutions in the medical domain, the patient’s life can become comfortable. This work recognizes the silent speech of three words. The decoding of silent speech can be useful for patients who are in a locked-in syndrome state. Moreover, it is also applicable to entertainment, cognitive biometrics, and brain-computer interfacing. Brain waves of these imagined words in the delta, theta, alpha, beta, gamma, and high gamma frequency bands are analysed. Covariance based connectivity features are extracted in each frequency band. The principal features which represent more than 95% of the variance are selected as a subset of the covariance connectivity matrix. This sub-set is tested on five classifiers. The maximum accuracy achieved is 76.4% in the theta band. Also, theta and high gamma band contain maximum information about imagined speech with average accuracies of 68.32% and 62.09% respectively
The Effectiveness of Ga Percent on the Electrical Characteristics of Al/CuIn1-xGaxSe2/ITO Schottky Junctions
Get PDFThe electrodeposition method has been employed to deposit our quaternary semiconductor thin films CuIn1-xGaxSe2 (CIGS) which is deposited on Indium Tin Oxide (ITO) substrates with different Gallium ratios (x=0, 0.2, 0.4, 0.6, 0.8 and 1). The structural and optical characteristics variation of the films with altering Ga percent has been studied. The impact of changing the Ga/(In+Ga) atomic ratio on the electrical transport characteristics of electrodeposited CIGS thin films has been investigated using I-V and C-V measurements. All junctions have revealed the Schottky behavior. The energy gap of the studied compositions has increased with increasing Ga content. This lowered the values of charge mobility in the investigated films. Besides, the optimum Ga/(In+Ga) atomic proportion in the view of the obtained results is achieved by adding Ga with 20 %. Also, this finding approves the validation of our proposed criterion in expecting the most efficient photovoltaic junctions. The obtained results could improve our current knowledge of the quaternary photovoltaic solar cells