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961.
Self‐Healing Properties of Protein Resin with Soy Protein Isolate‐Loaded Poly(d,l‐lactide‐co‐glycolide) Microcapsules 下载免费PDF全文
Self‐healing soy protein isolate (SPI)‐based “green” thermoset resin is developed using poly(d,l ‐lactide‐co‐glycolide)(PLGA) microcapsules containing SPI, as crack healant. The SPI–PLGA microcapsules with an average diameter of 778 nm that contain sub‐capsules are prepared using a water‐in‐oil‐in‐water double‐emulsion solvent evaporation technique. The encapsulation efficiency is found to be high, up to 89%. Thermoset green SPI resin containing the SPI–PLGA microcapsules successfully arrests and retards the microcracks. The healing efficiency is investigated using mode I fracture toughness test for resins containing different concentrations of microcapsules from 5 to 20 wt% and glutaraldehyde as a crosslinker at 9 or 12 wt%. The SPI resin containing 12 wt% glutaraldehyde and 15 wt% microcapsules shows self‐healing efficiency of up to 48%. It is observed that the SPI released from SPI–PLGA microcapsules can react with the excess glutaraldehyde present in the resin when the two come in contact within the microcracks and bridge the two fracture surfaces. The results of this study show for the first time that SPI–PLGA microcapsules can self‐heal protein‐based green resins. The same method can be extended to self‐heal other proteins as well as protein‐based green composites resulting in higher fracture toughness and longer useful life. 相似文献
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Tripathi Dipty Biswas Amit Tripathi Anil Kumar Singh Lalit Kumar Chaturvedi Amrita 《The Journal of supercomputing》2022,78(13):14813-14845
The Journal of Supercomputing - In this work, we propose a multi-tier architectural model to separate functionality and security concerns for distributed cyber-physical systems. On the line of... 相似文献
965.
Palepu Teja Ravindar Vidya Sagar Choppella Anil Kumar Mokshagundam M. Kiruba Sunil G. Babu Korupolu Raghu Babu L. John Berchmans Gosipathala Sreedhar 《材料科学前沿(英文版)》2018,12(4):405-414
Bismuth-based Sillen-Aurivillius compounds are being explored as efficient photocatalyst materials for the degradation of organic pollutants due to their unique layered structure that favours effective separation of electron-hole pairs. In this work, we synthesized Sillen-Aurivillius-related Bi2YO4Cl with the bandgap of 2.5 eV by a simple solid-state reaction and sensitized with rhodium nickel (RhNi) nanoparticles (NPs) to form the RhNi/Bi2YO4Cl heterostructure. Photocatalytic activities of BiOCl, Bi2YO4Cl and the RhNi/Bi2YO4Cl heterostructure were examined for the degradation of rhodamine- 6G under visible-light illumination. Results demonstrated that the photocatalytic dye degradation efficiency of RhNi/Bi2YO4Cl heterostructures is higher than those of BiOCl and Bi2YO4Cl, attributed to the synergistic molecular-scale alloying effect of bimetallic RhNi NPs. The plausible mechanism for the degradation of rhodamine-6G and the effective electron-hole pair utilization mechanism were discussed. 相似文献
966.
Mohamad Ghazi Droubi Alan Stuart John Mowat Craig Noble Anil Kumar Prathuru 《The Journal of Adhesion》2018,94(5):347-386
Failure behaviour of two types of adhesively bonded joints (composite-to-metal, metal-to-metal) has been studied under failure modes (Mode I: double cantilever beam (DCB) and Mode II: three-point end notch flexures (3-ENF)) using acoustic emission (AE) technique. The bonded specimens were prepared using two types of adhesive bond materials with three variations of adhesive bond quality. The effect of the presence of interfacial defects along the interface on the residual strength of the joint has also been studied. It was possible using the maximum AE amplitude method to select the AE events of mechanical significance. However, it proved difficult to propose a definitive AE trait for the mechanical phenomena occurring within specific AE event signals, for all adhesive types, bond qualities, and substrate configurations, therefore, all specimen combinations. There was a notable shift in spectral energy proportion as the AE source of mechanical significance varied along the specimen length for specimen combinations. However, it was difficult to confirm this distinctive trait for all specimen combinations due to difficulty in confirming the location and exact mechanical source. The proposed measurement technique can be useful to assess the overall structural health of a bonded system and may allow identification of defects. 相似文献
967.
Effect of a revolved wedge strut induced mixing enhancement for a hydrogen fueled scramjet combustor
Obula Reddy Kummitha K.M. Pandey Anil Kumar Reddy Padidam 《International Journal of Hydrogen Energy》2021,46(24):13340-13352
The mixing concept of fuel and air is the burning issue for hypersonic vehicles (scramjet) due to the less resident time of supersonic air in the combustion chamber. So far, significant research has been done for mixing enhancement and introduced different technologies; still, there is a lack of research for mixing improvement. Shock wave and shear mixing layer are the main parameters for investigating mixing criteria at supersonic speed. In this research, an innovative fuel injection strut has been designed to develop mixing enhancement by elevating multiple interactions between the shock wave and shear mixing layer. This new strut has been designed with the reference of the DLR scramjet combustor. From the reference of a wedge-shaped strut, a revolved (wedge shape – circular 3D) wedge strut has been modeled with the same fuel injection base points. This new strut's performance has been analyzed for mixing enhancement by visualizing the development of shock wave, shear-mixing layer, and their interactions. Three-dimensional numerical analysis has been carried out by solving the Reynolds-Averaged and Navier-Stokes (RANS) equations. A comparison of results has been made for the basic wedge and new strut and identified the increase in multiple interactions of the shock wave and shear layer, which leads to an increase in mixing enhancement. For the new strut, complete mixing has been achieved within a distance of 0.180 m with an average increase in mixing efficiency of 9% and increased pressure losses of 12%. 相似文献
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R. Vasudevan T. Karthik D. Selvakumar S. Ganesan R. Jayavel 《Journal of Materials Science: Materials in Electronics》2014,25(1):529-537
BaTiO3 nanoparticles were prepared by high energy ball milling and subjected to conventional and microwave post sintering at 1,000 °C. From the powder X-ray diffraction results, the synthesized material exhibits strong tetragonality with large c/a ratio. Scanning electron microscope results show the formation of tetragonal shaped BaTiO3 crystals in the nanometer scale and a significant reduction in the particle size for the microwave sintered sample. The reduced d-spacing of 1.741 Å with high crystallinity for the microwave sintered material is revealed by high resolution transmission electron microscopy analysis. Ultraviolet–visible spectroscopy studies confirm the higher optical band gap (Eg) of 4.157 eV for the microwave sintered sample. Microwave sintered sample shows a very high dielectric constant of εr = 4,445 with a low dielectric loss as tan δ = 0.0961. Microwave sintered sample exhibit a high polarization maximum of 73 μC/mm2 with reduced coercivity to be 0.293 kV/mm. 相似文献
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