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531.
The purpose of this research work is to investigate two-dimensional transient natural convective heat transfer and fluid flows in an undulated cavity by placing solid objects with isolated heated surfaces on the bottom wall. We discretize the coupled nonlinear transport equations using a higher-order compact finite-difference scheme. First, we test our scheme using existing experimental and numerical data. Then, we analyze the transient and steady-state natural convective flow phenomena for distributed heat sources on corrugations on the lower wall for a range of the Rayleigh number and Prandtl number . These simulated outcomes are presented in the form of central-line velocity , local and averaged Nusselt numbers, streamlines , dispersion of isotherms , and so forth. It is found that the transient fluid flow behavior is more magnificent than the steady-state solutions and shows the dominant behavior of the prominent primary cells over secondary cells, where it influences the heat transfer rates inside the entire enclosure. In steady states, at high Rayleigh numbers; convection dominates, formation of thermal boundary layers, compression of isotherms, and stratification of isotherms are significantly observed. Our results show many interesting flow phenomena that have not been analyzed previously. 相似文献
532.
Lei Wang Dawei Zhang Zheng-Dong Luo Pankaj Sharma Jan Seidel 《Advanced functional materials》2023,33(38):2303583
Mechanical friction leads to wear and energy dissipation, and its control is of high importance in new-generation miniature electromechanical devices. 2D materials such as graphene are considered to be excellent solid lubricants due to their ultralow friction and have attracted considerable research interest. Unique friction properties are discovered in various other 2D materials. However, the friction of functional van der Waals materials which have potential applications in novel nanoelectronics, like ferroelectric copper indium thiophosphate, has barely been studied. Herein, the study reports on the observation of inhomogeneous friction behavior existing in copper-deficient CuInP2S6 (Cu0.2In1.26P2S6), which exhibits a nanoscale phase separation of polar and non-polar crystalline phases. The paraelectric In4/3P2S6 phase exhibits higher friction than the ferroelectric CuInP2S6 phase, while phase boundaries between the two phases, interestingly, display the lowest friction. The origin of this phenomenon is attributed to different lattice strains of phases together with the presence of large strains at the nanoscale phase boundaries, which also manifests in the nonuniform tip-sample adhesion force. The findings provide new insights into nanoscale device design and wear behavior of a phase-separated van der Waals ferroelectric, which may help to reduce the power consumption of friction-exhibiting devices and extend their service life. 相似文献
533.
Journal of Computational Electronics - Surface plasmons (SP) can be effectively tuned in the entire UV–visible–near-infrared (NIR) spectrum, bringing together a variety of optical... 相似文献
534.
Ghaida Alosaimi Chien-Yu Huang Pankaj Sharma Tom Wu Jan Seidel 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(20):2207220
Exceptional electronic, optoelectronic, and sensing properties of inorganic Cs-based perovskites are significantly influenced by the defect chemistry of the material. Although organic halide perovskites that have a polycrystalline structure are heavily studied, understanding of the defect properties at the grain boundaries (GB) of inorganic Cs-based perovskite quantum dots (QDs) is still limited. Here, morphology-dependent charge carrier dynamics of CsPbBr3 quantum dots at the nanoscale by performing scanning probe microscopy of thermally treated samples are investigated. The grain boundaries of defect-engineered samples show higher surface potential than the grain interiors under light illumination, suggesting an effective role of GBs as charge collection and transport channels. The lower density of crystallographic defects and lower trap density at GBs specifically of heat-treated samples cause insignificant dark current, lower local current hysteresis, and higher photocurrent, than the control samples. It is also shown that the decay rate of surface photovoltage of the heated sample is quicker than the control sample, which implies a considerable impact of ion migration on the relaxation dynamic of photogenerated charge carriers. These findings reveal that the annealing process is an effective strategy to control not only the morphology but also the optoelectrical properties of GB defects, and the dynamic of ion migration. Understanding the origin of photoelectric activity in this material allows for designing and engineering optoelectronic QD devices with enhanced functionality. 相似文献
535.
Journal of Computational Electronics - An open-base metal–semiconductor–metal Schottky silicon nanowire (MSM-SiNW) biristor device is applied for ultrasensitive, label-free, real-time... 相似文献
536.
Silicon - This work investigates the effects of temperature on the performance of a 5-nm node N-channel Nanosheet Transistor (NST) for analog applications. A fully calibrated commercial TCAD... 相似文献
537.
Keserwani Pankaj Kumar Govil Mahesh Chandra Pilli Emmanuel S. 《Neural computing & applications》2023,35(7):4993-5013
Neural Computing and Applications - The technological advancement leads to an increase in the usage of the Internet with many applications and connected devices. This increased network size causes... 相似文献
538.
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
539.
Dr. Pankaj E. Hande Dr. Yogesh G. Shelke Prof. Dr. Anindya Datta Prof. Dr. Santosh J. Gharpure 《Chembiochem : a European journal of chemical biology》2022,23(5):e202100448
Intracellular pH plays an important role in many biological and pathological processes. Small-molecule based pH probes are found to be the most effective for pH sensing because of ease of preparation, high sensitivity, and quick response. They have many advantages such as small perturbation to the functions of the target, functional adaptability, cellular component-specific localization, etc. The present review highlights the flurry of recent activity in the development of such probes. The probes are categorized based on the type of fluorophore used like quinoline, coumarin, BODIPY, rhodamine, indolium, naphthalimide, etc., and their analytical performance is discussed. 相似文献
540.
International Journal of Information Security - Phishing is one of the most dangerous threats in which a hacker imitates a person, company or government agency to lure and deceive their victims.... 相似文献