KRISHAN KUMAR PATEL, RAJESH PUROHIT

Journal of Polymer Materials, Vol.36, No.1, pp. 23-37, 2019, DOI:10.32381/JPM.2019.36.01.3

Abstract Microwave (MV)-induced thermo-responsive shape memory thermoplastic polyurethane (SMTPU)/ MWCNT composites were prepared in micro-compounder. Composites containing different amount of multiwall Carbon nanotube (MWCNT) varying from 0 to 1.5 phr in SMTPU matrix were prepared. Maximum stretching strength, recovery force and tensile strength for 1.5 CNTPU (1.5 phr MWCNT in SMTPU matrix) was increased by 120%, 100% and 24% respectively as compared to SMTPU. MV-induced shape memory is a novel approach for fast, clean and remote heating during operation. MWCNT is strong absorber of microwave irradiation so that SMTPU/ MWCNTs nanocomposites successfully triggered by microwave. More >

Benjamin Lepers^a,*, Aditya Putranto^b,c, Martin Umminger^d, Guido Link^a, John Jelonnek^a

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-11, 2014, DOI:10.5098/hmt.5.13

Abstract The use of high power microwaves to perform explosive spalling of surface concrete is a promising technique with applications in the area of concrete facilities decommissioning. The mechanism that creates explosive spalling is an interactive process of the thermal stress from high temperature gradients and the pore pressure generated from the water vaporization. In order to better predict the total stress distribution, the temperature has to be calculated by including the effect of water vaporization and water transport through a porous medium. In this paper, a one dimensional model solving the heat and diffusion equation for liquid and vapor phase… More >

Benjamin Lepers^a,∗, Thomas Seitz^a, Guido Link^a, John Jelonnek^a,b, Mark Zink^c

Frontiers in Heat and Mass Transfer, Vol.6, pp. 1-6, 2015, DOI:10.5098/hmt.6.20

Abstract A compact 10 kW microwave applicator operating at 2.45 GHz for fast volumetric heating and thermal cracking of lignite briquettes has been successfully designed and tested. In this paper, the applicator design and construction are presented together with a sequentially coupled electromagnetic, thermal-fluid and mechanical Comsol model. In a first step, this model allows us to calculate the power density inside the lignite material and the temperature distribution in the applicator for different water flow rates. In a second step, the total stress due to the thermal dilatation, the internal pressure inside the ceramic and the contact pressure from the… More >

Nure Alam Chowdhury¹, Lulu Wang^2,*, Md Shazzadul Islam³, Linxia Gu¹, Mehmet Kaya^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.2, pp. 1301-1322, 2024, DOI:10.32604/cmes.2023.030844

Abstract This study designs a microstrip patch antenna with an inverted T-type notch in the partial ground to detect tumor cells inside the human breast. The size of the current antenna is small enough (18 mm × 21 mm × 1.6 mm) to distribute around the breast phantom. The operating frequency has been observed from 6–14 GHz with a minimum return loss of −61.18 dB and the maximum gain of current proposed antenna is 5.8 dBi which is flexible with respect to the size of antenna. After the distribution of eight antennas around the breast phantom, the return loss curves were observed in the presence and absence of tumor cells inside… More > Graphic Abstract

Lei Liu^*, Shenao Pang, Zhuhui Luo

Journal of Renewable Materials, Vol.11, No.11, pp. 3891-3906, 2023, DOI:10.32604/jrm.2023.028192

Abstract The recycling of carbon fibers and protection from unwanted microwave radiation are two important environmental issues that need to be addressed in modern society. Herein, branched carbon nanofibers (CNFs) were grown in-situ on recycled carbon fibers (RCFs) through the chemical vapor deposition method using nickel as catalysts and thiophene as aided-catalysts. The effect of thiophene on the growth morphology of CNFs was investigated. Correspondingly, branched CNFs-RCFs and straight CNFs-RCFs were respectively obtained in the presence and absence of thiophene. The microstructure and electromagnetic behaviour investigations have shown that the branched CNFs possess a typical multi-branched structure, with more defects, pores… More > Graphic Abstract

Jianping Deng¹, Qianqian Zhang¹, Yuling Lan¹, Lingcong Luo¹, Zimin Dai¹, Zhonghang Lin¹, Zhixin Lu¹, Jiancheng Yuan¹, Yiqi Fu¹, Lu Luo^2,*, Weigang Zhao^1,*

Journal of Renewable Materials, Vol.11, No.6, pp. 2631-2646, 2023, DOI:10.32604/jrm.2023.027163

Abstract The development and utilization of biomass and agroforestry processing byproducts for high-value applications have been an important topic in the field of renewable materials research. Based on this, a two-step microwave hydrothermal pre-carbonization and KOH activation method was proposed to synthesize tannin-based activated carbons with a high specific surface area, hierarchical pore structure, and good electrochemical performance. The microstructure, texture properties, and physicochemical characteristics were investigated. The results show that the prepared tannin-based activated carbons presented a hierarchical pore structure (micro- and mesopores) with a specific surface area as high as 997.46 m³ g⁻¹ . The electrochemical analysis shows that… More > Graphic Abstract

Mohd Aminudin Jamlos^1,*, Nur Amirah Othman¹, Wan Azani Mustafa², Mohd Faizal Jamlos³, Mohamad Nur Khairul Hafizi Rohani²

CMC-Computers, Materials & Continua, Vol.75, No.1, pp. 277-292, 2023, DOI:10.32604/cmc.2023.032840

Abstract Metamaterials (MTM) can enhance the properties of microwaves and also exceed some limitations of devices used in technical practice. Note that the antenna is the element for realizing a microwave imaging (MWI) system since it is where signal transmission and absorption occur. Ultra-Wideband (UWB) antenna superstrates with MTM elements to ensure the signal transmitted from the antenna reaches the tumor and is absorbed by the same antenna. The lack of conventional head imaging techniques, for instance, Magnetic Resonance Imaging (MRI) and Computerized Tomography (CT)-scan, has been demonstrated in the paper focusing on the point of failure of these techniques for… More >

Sheng He¹, Weiqi Leng^2,*, Yuhe Chen¹, Hongchen Li³, Jingpeng Li¹, Zaixing Wu¹, Zizhang Xiao¹

Journal of Renewable Materials, Vol.11, No.1, pp. 321-331, 2023, DOI:10.32604/jrm.2023.022097

Abstract Microwave (MW) drying method was adopted to enhance the liquid permeability of Scots pine lumber. Structure changes were characterized by stereoscope microscope, scanned electron microscope (SEM) and transmission electron microscope (TEM) examination. Pore parameters before and after MW treatment were detected by mercury intrusion porosimetry (MIP) method, and the effect of structure changes on liquid permeability were analyzed. As stereoscope microscope, SEM and TEM examination results shown, macro and micro checks mainly developed at intercellcular of tracheids, intercellular of ray parenchyma and tracheid, while these checks extend main along the radial-longitudinal plane. Pit border destruction, aspirated pits’ orus translocation and… More >

Xiya Yu¹, Nianfeng Wei², Qisong Liu², Zhiyong Wu², Mizi Fan³, Weigang Zhao^1,*, Qinzhi Zeng^1,*

Journal of Renewable Materials, Vol.10, No.8, pp. 2041-2053, 2022, DOI:10.32604/jrm.2022.018027

Abstract To improve the mechanical properties of fast-growing Chinese fir (Cunnighamia lanceolate), expand its range of application, increase its value, and avoid the environmental pollution caused by impregnation with synthetic resin, Chinese fir was impregnated with a shellac solution. Since the shellac solution was difficult to penetrate into fast-growing Chinese fir, so microwave pretreatment was used to irradiate the wood to improve the permeability. This study investigated the effects of four factors, including the content of moisture in the wood before it was microwaved, the chamber pressure of microwave, the time of microwaving and the vacuum impregnation on the mechanical properties… More > Graphic Abstract

N. A. Koma'rudin¹, Z. Zakaria^1,*, A. A. Althuwayb², H. Lago³, H. Alsariera¹, H. Nornikman¹, A. J. A. Al-Gburi¹, P. J. Soh^4,5

CMC-Computers, Materials & Continua, Vol.72, No.1, pp. 983-998, 2022, DOI:10.32604/cmc.2022.024782

Abstract This work proposes a wideband and unidirectional antenna consisting of dual layer of coplanar waveguide based on the circular parasitic element technique. The design procedure is implemented in three stages: Design A, which operates at 3.94 GHz with a bandwidth of 3.83 GHz and a fractional bandwidth (FBW) of 97.2%; Design B, which operates at 3.98 GHz with a bandwidth of 0.66 GHz (FBW of 56.53%); and Design C as the final antenna. The final Design C is designed to resonate at several frequencies between 2.89 and 7.0 GHz for microwave imaging applications with a bandwidth of 4.11 GHz (79.8%)… More >