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排序方式: 共有639条查询结果,搜索用时 15 毫秒
631.
Vidyacharan Gopaluni Venkata Theodore Rex Orth Wenyang Pan Amirhossein Amini G. M. Homsy Tianshu Liu 《Advanced functional materials》2023,33(30):2301072
A new wetting mechanism, termed electro-elastic wetting, and methods to exploit it for droplet manipulation are proposed and demonstrated. The system consists of a droplet of dielectric liquid, an elastic and conductive membrane as its shell, and an electrode-dielectric composite as its substrate. Activation is by an electric field applied between the membrane and the substrate. The equilibrium shape of the droplet is determined by the balance of membrane tension and electrostatic attraction. It is shown that the contact angle of the droplet is governed by a modified Young–Lipmann Equation. It is then demonstrated that it is possible to transport the droplet along a controlled direction, as well as to actively tune its shape, topography, and position by manipulating the spatial distribution of the electrical force. 相似文献
632.
Lei Liu Jiabing Feng Yijiao Xue Venkata Chevali Yubai Zhang Yongqian Shi Long-Cheng Tang Pingan Song 《Advanced functional materials》2023,33(9):2212124
Frequent fire disasters have caused massive impacts to the environment, human beings, and the economy. MXene has recently been intensively researched as potential flame retardants to provide passive fire protection for other materials via its physical barrier and catalyzing carbonization effects. In parallel, MXene has also demonstrated a great promise for creating early fire warning sensors, which is an emerging field that has the potential to provide active fire response through its thermoelectric effect. This makes it possible to integrate passive fire retardancy and active fire warning into one MXene-based fire protection system on demand. However, fulfilling these promises needs more research. Herein, an overview of passive flame-retardant materials and next-generation smart fire warning materials/sensors based on MXene and its derivatives is provided. This study reviews their conceptual design, characterization, modification principles, performances, applications, and mechanisms. A discussion of the challenges that need to be solved for their future practical applications and opportunities is also presented. 相似文献
633.
Devendra Sharma Priyanka Choudhary Sahil Kumar Venkata Krishnan 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(11):2207053
Transition metal phosphides (TMP) posses unique physiochemical, geometrical, and electronic properties, which can be exploited for different catalytic applications, such as photocatalysis, electrocatalysis, organic catalysis, etc. Among others, the use of TMP for organic catalysis is less explored and still facing many complex challenges, which necessitate the development of sustainable catalytic reaction protocols demonstrating high selectivity and yield of the desired molecules of high significance. In this regard, the controlled synthesis of TMP-based catalysts and thorough investigations of underlying reaction mechanisms can provide deeper insights toward practical achievement of desired applications. This review aims at providing a comprehensive analysis on the recent advancements in the synthetic strategies for the tailored and tunable engineering of structural, geometrical, and electronic properties of TMP. In addition, their unprecedented catalytic potential toward different organic transformation reactions is succinctly summarized and critically analyzed. Finally, a rational perspective on future opportunities and challenges in the emerging field of organic catalysis is provided. On the account of the recent achievements accomplished in organic synthesis using TMP, it is highly anticipated that the use of TMP combined with advanced innovative technologies and methodologies can pave the way toward large scale realization of organic catalysis. 相似文献
634.
Sandan Kumar Sharma Kapil Chaudhary Yashpal Gupta Mitjan Kalin B. Venkata Manoj Kumar 《International Journal of Applied Ceramic Technology》2022,19(3):1691-1701
Spark plasma sintering of SiC-10, 20, or 30 wt% TaC composites was performed at 1800°C. Microstructures of sintered composites revealed uniform dispersion of TaC particles in SiC matrix. With the increase in TaC content, hardness decreased from 25.75 to 23.30 GPa and fracture toughness increased from 3.48 to 3.85 MPa m1/2. Erosion testing was performed to evaluate the potential of sintered composites at room temperature and 400°C by a stream of SiC particles impinging at different angles (30°, 60°, or 90°). The erosion rate varied from 25 to 166 mm3/kg, with change in TaC content, impingement angle, or temperature. The erosion rate increased as the angle of impingement and temperature increased, but reduced when the TaC concentration increased. Worn surfaces revealed that the material was dominantly removed via fracture of SiC grains and TaC particles pull-out. SiC-30 wt% TaC composites exhibited superior erosive wear resistance at low impingement angle and room temperature. 相似文献
635.
636.
Venkata Lakshmaiah Y Bappadittya Roy 《International Journal of Communication Systems》2023,36(7):e5453
This article introduces a super wideband along with three notch bands circular patch monopole antenna. The design structure is applicable for microwave and high-speed wireless devices (2.19 to 25 GHz). In order to create a broad band, a ring dimension circular patch is used. To generate three notch bands, six symmetrical tiny cylinder stubs are introduced on the ground. These notch band frequencies can eliminate unwanted interference from various wireless frequencies, which mainly cover three notch bands: 5.5–7.3, 12.05–14.46, and 17.71–19.5 GHz. The steady radiation, super bandwidth, and stable gain properties expand when the ring patch and line feed are combined. It is excellent for many UWB applications because of its compact size (39 × 29 mm 2) and large bandwidth (166.97% fractional bandwidth). This model employs various size reduction and matching approaches to get a better response. The mechanisms of these structures are identified, and overall performance is compared with parametric analysis, tables, and figure. 相似文献
637.
In this study, multiphase Eulerian computational fluid dynamics (CFD) modelling is developed to predict the hydrodynamics, mass transfer, and chemical absorption of CO2 using a monoethanolamine (MEA) solution in a structured packed column. First, the hydrodynamic simulation of liquid dispersion in a structured packed bed using a two-dimensional CFD is performed. The simulation results of the radial distribution of the liquid holdup are compared with the literature experimental data. The model prediction matches the experimental data at the top position of the column, whereas a slight deviation is found at the bottom position of the column. Using a validated CFD model, the reactive mass transfer is modelled to study CO2 capture in a structured packed column with Mellapak 500.X. The model results are compared to the literature experimental results of CO2 mole fractions along the height of the column. It is found that the model results match the experimental findings. Furthermore, CFD modelling is extended to investigate the influence of operating conditions such as gas and liquid velocities on CO2 removal efficiency. The present CFD model demonstrates the porous media approach for reactive absorption of CO2 in a structural packed bed. 相似文献
638.
Nigam Kaushal Kondekar PN Chandan Bandi Venkata Kumar Satyendra Tikkiwal Vinay Anand Dharmender Singh Km. Sucheta Bhardwaj Eshaan Choubey Shubham Chaturvedi Savitesh 《SILICON》2022,14(4):1549-1558
Silicon - To overcome the fabrication complexity and achieve a better switching ratio is a major grave concern for applications in semiconductor devices. In this regards, a novel stack gate-oxide... 相似文献
639.
Sireesha Veeramachaneni Srinivas K. Pisipaty Arulanantham Brusly Solomon Venkata C. Vadisa Dharma R. Vedula Devisetty Srinivasa Rao 《亚洲传热研究》2023,52(3):2715-2742
The existing work deals with the evaluation of compact loop heat pipe by means of a low thermal conductivity sintered chrysotile wick to avoid large heat leaks as of the evaporator to the compensation chamber. Accordingly, a wick with low thermal conductivity (0.068–0.098 W/mK) chrysotile powder of a mean particle diameter of 3.4 μm is fabricated through sintering. Nine chrysotile wicks are sintered with different compositions of binders (bentonite and dextrin) and pore-forming agent NaCl at sintering temperatures of 500°C, 600°C, and 700°C with a sintering time of 30 min. The wick properties, for instance, porosity, permeability, wettability, and capillary rise are studied owing to sintering temperature. Consequently, it is observed that a pure chrysotile powdered wick at a sintering temperature of 600°C exhibits a high porosity of 61.8% with permeability 1.04 × 10−13 m2 and a capillary rise of 4.5 cm in 30 s and is considered optimal. This optimal wick is used for performance evaluation in compact loop heat pipe and a decrease of 36.1% in thermal resistance is found when compared with copper mesh wick in a loop heat pipe. The lowermost thermal resistance originates to be 0.147 K/W at 120 W with wall temperature 57.7°C. This indicates that loop heat pipe with sintered chrysotile wick can operate at lower heat loads efficiently when compared with copper mesh wick and as heat load increases a chance of dry out condition occurs. The highest evaporative heat transfer coefficient obtained is 65.7 kW/m2 K at a minimum heat load. 相似文献