Microwave irradiation is one of the most effective strategies to accelerate the curing of resin. However, the mechanism is still unclear. The debates mainly focus on how to quantitatively evaluate the 'non-thermal' effect of the microwave. In this work, the non-thermal effect on DGEBA with amine (D230) and anhydride (MHHPA) hardeners respectively was evaluated an isothermal microwave curing reactor. The 'thermal effect' caused by the microwave was peeled off accurately. Iso-conversional kinetic analysis was performed based on the reaction extent from the real time FTIR spectrum, and the apparent activation energy ( ) was calculated for the quantitative evaluation of the microwave non-thermal effect. The influence caused by the polarized functional groups, reaction temperature and the transition state were explored, and the microwave non-thermal effect on the mechanical performance of the cured thermosets was evaluated. Results indicated that the microwave non-thermal effect was able to reduce the and accelerate the curing speed of epoxy resin. At the same time, the final curing extent was increased when the non-thermal effect of microwave was induced leading to enhanced mechanical and thermal performance.
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http://dx.doi.org/10.1039/d0ra08427a | DOI Listing |
Foods
December 2024
College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021, China.
Microwave electrodeless ultraviolet (MWUV) technology, as an emerging food processing technique, has garnered growing attention in the realm of food science in recent years. Based on different application requirements, MWUV equipment types are categorized as microwave oven reactor, continuous-flow UV-microwave reactor, coaxially driven MWUV reactor, and complete ultraviolet reactor. The luminescence properties of MWUV equipment depend on their filler gas; mercury is commonly used as a filler gas to produce a wavelength at 253.
View Article and Find Full Text PDFSci Rep
December 2024
Institute of Radioelectronics and Multimedia Technology, Warsaw University of Technology, Warsaw, Poland.
The effects of 5.8-GHz microwave (MW) irradiation on the synthesis of mesoporous selenium nanoparticles (mSeNPs) in aqueous medium by reduction of selenite ions with ascorbic acid, using zinc nanoparticles as a hard template and cetyltrimethylammonium bromide (CTAB) as a micellar template, are examined for the first time with a particular emphasis on MW-particle interactions and the NPs morphology. This MW-assisted synthesis is compared to 2.
View Article and Find Full Text PDFFood Chem X
December 2024
Department of Family and Consumer Sciences, University of Ghana, Accra, Ghana.
Potato is a highly nutritious staple food however, it also contains some antinutrients like alkaloids, phytates, tannins, oxalates as well as pesticide residues. Therefore, this study was conducted to reduce the loads of antinutrients and pesticides in potato powder (PP) using thermal and non-thermal processing techniques. Nutritional analysis revealed that the raw PP contained significantly ( < 0.
View Article and Find Full Text PDFCompr Rev Food Sci Food Saf
January 2025
Department of Food Process Engineering, National Institute of Technology Rourkela, Odisha, India.
The presence of Bacillus cereus in spices and herbs has posed a detrimental effect on food safety. The absence of thorough testing, comprehensive reporting, and vigilant surveillance of the illness has resulted in a significant underestimation of the true prevalence of foodborne illness caused by B. cereus.
View Article and Find Full Text PDFSurg Neurol Int
November 2024
Independent Researcher, Ronchin, France.
Background: Scientific literature, with no conflicts of interest, shows that even below the limits defined by the International Commission on Non-Ionizing Radiation Protection, microwaves from telecommunication technologies cause numerous health effects: neurological, oxidative stress, carcinogenicity, deoxyribonucleic acid and immune system damage, electro-hypersensitivity. The majority of these biological effects of non-thermal microwave radiation have been known since the 1970s.
Methods: Detailed scientific, political, and military documents were analyzed.
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