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931.
Rahul Chandra Pradhan Abhishek Gautam Tripathy Kumar Shantanu Prasad Barada Prasanna Sahoo Diptikanta Das Ramanuj Kumar 《Materialwissenschaft und Werkstofftechnik》2023,54(8):986-1002
Multiwall carbon nanotube buttressed aluminium 7075 metal matrix composite was synthesized through an amended liquid metallurgy method, which consisted semisolid stirring, ultrasonic treatment and squeeze casting. Aim was to investigate its machinability and surface morphology during electrical discharge machining. Variable machining factors were peak current, pulse-on time and gap voltage, whereas the responses under investigation were electrode wear rate, material removal rate and average surface roughness. Results revealed electrode wear rate, material wear rate and average surface roughness increased on increasing peak current and pulse-on time, but all these responses behaved inversely with the increase of gap voltage. Average surface roughness reduced by around 44 % on reducing the peak current from 10 A to 4 A and increasing gap voltage from 55 V to 80 V at constant pulse-on time of 300 μs; however, it increased by around 25 % on reducing the gap voltage from 80 V to 55 V and increasing the pulse-on time from 100 μs to 300 μs at constant peak current of 10 A. Significance of the process parameters were verified, regression models were developed and morphology of the machined surfaces was studied. Finally, multiple response optimization was conducted following grey relational approach. 相似文献
932.
Shubham Jaiswal Jeet Vishwakarma Shubham Bhatt Saheb Karak Pankaj Bharti Chetna Dhand Rajeev Kumar Pradip Kumar Mohammad S. M. Saifullah Surajit Saha Rahul Mishra Neeraj Dwivedi 《Advanced Engineering Materials》2023,25(17):2300233
Stimuli-responsive materials can frequently tune between their temporary and original shapes, and have the potential for artificial intelligence-based technologies in robotics, aerospace, biomedical, engineering, security, etc. Shape memory polymers (SMPs) are promising for these technologies but their inadequate thermal and electrical characteristics causing slow shape recovery limit their practical applications. Herein, for the first time, comprehensively and precisely the shape memory polyurethane (PU), a promising SMP, via a variety of novel layered titanium carbides fillers, namely, Ti2AlC (MAX1), Ti3AlC2 (MAX2), and Ti3C2 (MXene), is engineered. The resultant PU-composites show 30–50% faster shape recovery in different environments, 20–25% greater extent of shape recovery in the load-constrained environment, 100–125% higher thermal conductivity, and 700–16 000× higher electrical current. Importantly, the reinforcement of even a small amount of MAX and MXene (such as 0.25 wt%) has largely boosted the performance of PU. Considering ease of processability and performance enhancement factors, the MAX-phase fillers may be preferred over MXene-phase fillers for next-generation composites development. Employing PU composite component as both heat-sensor and actuator, a unique heat detector/fire alarm device that works successfully in simulated heat and fire environments is demonstrated. This work is crucial for enabling futuristic technologies. 相似文献
933.
Anand Rahul Nayak Bibhuti B. Behera Shantanu K. 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(9):3546-3555
Journal of Inorganic and Organometallic Polymers and Materials - The current investigation describes the synthesis of SiTiCNO ceramics derived from the mixture of a preceramic polymer... 相似文献
934.
Kumar Saurabh Manda Sanjay Tewary Ujjal Mahesh Sivasambu Balamuralikrishnan R. Verma Rahul Kumar Sambandam Manjini Karagadde Shyamprasad Samajdar Indradev 《Metallurgical and Materials Transactions A》2023,54(4):1236-1251
Metallurgical and Materials Transactions A - This study involved laboratory unidirectional (UDR) and reverse (RR) cold rolling of steel, and corresponding direct (and indirect) observations of... 相似文献
935.
Sharma Ashish Vijay Rahul Kumar Nanda Satyasai Jagannath 《Neural computing & applications》2023,35(11):8081-8108
Neural Computing and Applications - Seismic catalogs are vital to understanding and analyzing the progress of active fault systems. The background seismicity rate in a seismic catalog, strongly... 相似文献
936.
Modak Pranabananda Tyagi Kushagra Chakrabarti Debalay Mitra Rahul Patra Sudipta 《Metallurgical and Materials Transactions A》2023,54(3):1024-1041
Metallurgical and Materials Transactions A - The study focuses on the processing of thick plate (≥ 12 mm) and strip (3 to 4 mm) where hot-rolling reduction is... 相似文献
937.
Bikash Das Subrata Ghosh Shamashis Sengupta Pascale Auban-Senzier Miguel Monteverde Tamal Kumar Dalui Tanima Kundu Rafikul Ali Saha Sujan Maity Rahul Paramanik Anudeepa Ghosh Mainak Palit Jayanta K. Bhattacharjee Rajib Mondal Subhadeep Datta 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(39):2302240
Manipulation of long-range order in 2D van der Waals (vdW) magnetic materials (e.g., CrI3, CrSiTe3 ,etc.), exfoliated in few-atomic layer, can be achieved via application of electric field, mechanical-constraint, interface engineering, or even by chemical substitution/doping. Usually, active surface oxidation due to the exposure in the ambient condition and hydrolysis in the presence of water/moisture causes degradation in magnetic nanosheets that, in turn, affects the nanoelectronic /spintronic device performance. Counterintuitively, the current study reveals that exposure to the air at ambient atmosphere results in advent of a stable nonlayered secondary ferromagnetic phase in the form of Cr2Te3 (TC2 ≈160 K) in the parent vdW magnetic semiconductor Cr2Ge2Te6 (TC1 ≈69 K). The coexistence of the two ferromagnetic phases in the time elapsed bulk crystal is confirmed through systematic investigation of crystal structure along with detailed dc/ac magnetic susceptibility, specific heat, and magneto-transport measurement. To capture the concurrence of the two ferromagnetic phases in a single material, Ginzburg-Landau theory with two independent order parameters (as magnetization) with a coupling term can be introduced. In contrast to the rather common poor environmental stability of the vdW magnets, the results open possibilities of finding air-stable novel materials having multiple magnetic phases. 相似文献
938.
Subir Kumar Chakraborty A. Subeesh Rahul Potdar Narendra Singh Chandel Dilip Jat Kumkum Dubey Pramod Shelake 《野外机器人技术杂志》2023,40(6):1581-1602
The modernization of postharvest operations and penetration of emerging technologies in horticultural processing have provided intelligent solutions for reducing postharvest losses. Work environmental and occupational health issues require immediate attention as the awkward posture and continuous drudgery-prone on-farm sorting and grading activities may lead to musculoskeletal disorders. The main objective of this study was to develop an automatic farm-friendly machine for real-time citrus fruit washing, image-based sorting, and weight grading; designed optimally and equipped with an embedded system comprising a lightweight convolutional neural network (CNN) model. Also included in this study was a thorough ergonomic assessment of the developed machine in a real work environment. The parametric choice of the fruit washing and singulation system was performed by employing computational fluid dynamics modeling and response surface methodology designed optimization. It was observed that under steady-state conditions, the water jet would arrive at a velocity of 11.36 m/s which would eventually suit a singulation conveyor with a slope of 25°. A noninvasive grading and sorting approach for citrus fruits is presented in this paper that leverages deep learning to classify the fruits into “accept” and “reject” classes. The custom lightweight CNN model “SortNet” has shown excellent classification results with an overall accuracy of 97.6%. The ergonomic evaluation shows that the average body part discomfort score in case of operating an automatic fruit grading machine was much lower (12.3 ± 2.0) than the traditional method (30.9 ± 3.3). Further, in the case of machine operation, the percentage load on the muscles ranged from 28.67 to 34.31 reflecting that subjects can work for longer duration on the machine without fatigue as compared with the traditional manual operation. 相似文献
939.
Data reconciliation (DR) is one of the primary error handling methods to reduce measurement errors in industries that may otherwise cause misleading information about the plant. In this article, the mathematical aspects of measurement errors and their treatment by DR are discussed in detail. The flaws in the existing DR methods have been identified and re-investigated. More importantly, the feasibility and health check-up of the DR problem have been discussed. The primary objective of the work is to develop a DR code based on the observations made in the present study, which involves DR solutions by both successive linearization (SL) and sequential quadratic programming (SQP) schemes. Benchmarking of the code with standard cases showed its wider suitability in solving DR problems. The algebraic SL method was found suitable for proper data health check-ups and reliable solutions, whereas SQP was robust. The developed code was tested successfully for a chemical plant as well. 相似文献