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991.
Doddamani Saleemsab Kaleemulla Mohamed 《Journal of Failure Analysis and Prevention》2019,19(3):730-737
Journal of Failure Analysis and Prevention - This paper exhibits the investigative work conducted on fracture toughness of aluminum–graphite metal matrix composites. The materials chosen for... 相似文献
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Cissé Mohamed N'guessan Elise Tia V. Etienne Gérard Loiseau Didier Montet 《Journal of Food Safety》2020,40(3):e12785
Lactoperoxidase system (LPOS) was incorporated into chitosan solutions (0.5, 1, and 1.5%) to protect mangoes against two strains of fungi. Coating solutions effectiveness in vitro (in Petri dish) and in vivo (on mango) were studied on fungal (Phomopsis sp. RP257 and Pestalotiopsis sp.) growth isolated from mango cv Amelie. In vitro, chitosan concentration at least 1% containing or not LPOS effectively inhibited Pestalotiopsis sp. growth at 100%. Presence of LPOS or Lactoperoxydase system with iodine (LPOSI) in chitosan at 0.5% increased the percentage of inhibition from 26 to 93%. Edible films with LPOS inhibited Phomopsis sp. RP257 particularly when LPOS was incorporated in chitosan concentrations of 1 and 1.5%. Iodine did not influenced antifungal activity of LPOS against Pestalotiopsis sp. but decreased activity antifungal toward Phomopsis sp. RP257. The properties (water vapor permeability and mechanical properties) of chitosan films were not significantly changed by the incorporation of the enzyme system. in vivo condition, chitosan coating at 1 and 1.5% with or without enzyme system was sufficient to inhibit totally (100%) Pestalotiopsis sp. and was 60% efficient against Phomopsis sp. with chitosan only at 1 and 1.5%. However, when coating solution mainly at 1 and 1.5% was enhanced by LPOS with or without iodine, it inhibited totally (100%) Phomopsis sp. RP257. The presence of iodine slightly reduced antifungal activity against Phomopsis sp. RP257. 相似文献
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Wafaa Mohamed SHABAN Khalid ELBAZ Mohamed AMIN Ayat gamal ASHOUR 《Frontiers of Structural and Civil Engineering》2022,16(3):329
This study presents a new systematic algorithm to optimize the durability of reinforced recycled aggregate concrete. The proposed algorithm integrates machine learning with a new version of the firefly algorithm called chaotic based firefly algorithm (CFA) to evolve a rational and efficient predictive model. The CFA optimizer is augmented with chaotic maps and Lévy flight to improve the firefly performance in forecasting the chloride penetrability of strengthened recycled aggregate concrete (RAC). A comprehensive and credible database of distinctive chloride migration coefficient results is used to establish the developed algorithm. A dataset composite of nine effective parameters, including concrete components and fundamental characteristics of recycled aggregate (RA), is used as input to predict the migration coefficient of strengthened RAC as output. k-fold cross validation algorithm is utilized to validate the hybrid algorithm. Three numerical benchmark analyses are applied to prove the superiority and applicability of the CFA algorithm in predicting chloride penetrability. Results show that the developed CFA approach significantly outperforms the firefly algorithm on almost tested functions and demonstrates powerful prediction. In addition, the proposed strategy can be an active tool to recognize the contradictions in the experimental results and can be especially beneficial for assessing the chloride resistance of RAC. 相似文献
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Mohamed Janshir Bin Gulam Mohamed Hafiz Abdul Mannan Rizwan Nasir Dzeti Farhah Mohshim Hilmi Mukhtar Aymn Abdulrahman Anas Ahmed 《应用聚合物科学杂志》2020,137(12):48476
Membrane technology has been considered a key factor for sustainable growth in high-efficiency gas separation. Current mixed matrix membranes (MMMs) technology is rising, but these membranes in the dense structure are having difficulties in operating at high pressures and scale up for commercialization. The purpose of this research is to synthesize composite MMMs (CMMMs) consisting of polyethersulfone (PES), carbon molecular sieve (CMS 1–5 wt %), and Novatex 2471 nonwoven fabric (support layer). The membranes' physical, chemical, and thermal properties were evaluated by different analytical equipment. The morphology of both PES and PES-CMS composite membranes had a porous and asymmetric structure, in which CMS was uniformly distributed in the polymer matrix. The thermal properties showed that the membranes were stable up to 350 °C with a single glass transition temperature. The functional groups in the membrane were confirmed by spectral analysis. The gas performance results showed that carbon dioxide permeance increased with increased CMS concentration and methane permeance decreased due to the hindering effect of CMS under similar operating conditions. The highest selectivity achieved was 12.774 using CMMM of 5 wt % of CMS at 10 bar, which on average was 137.80%, improved selectivity compared to pure PES membrane. The support layer was able to withstand high operating pressures and showed the ability to scale up. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48476. 相似文献
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Because of the superior photocatalytic activities of nanocrystalline TiO2 and ZnO under UV irradiation, they were embedded into the glass system (SiO2, TiO2, ZnO, B2O3, Na2O, K2O, P2O5, Li2O and BaO) to provide easy separation from the aqueous system. Different contents of TiO2 and ZnO have been investigated. Conversion to glass-ceramic materials was carried out by heat treatment at 450 °C, which is the onset of the nucleation peak according to the differential thermal analysis (DTA) result, for different times. This heat treatment regime preserves the transparency of the prepared materials in the visible region and good absorption in the UV region. The high content of TiO2 or ZnO caused an improvement of microhardness of the prepared materials, though the presence of the two oxides with the same ratio decreased the microhardness values. Photocatalytic activity of the prepared glass-ceramic materials was investigated according to their efficiency for the degradation of humic acid (HA), the major precursor of disinfection by-products (DBPs), from water. All samples were proved to be photoactive with different extents. Four hours heat treatment at 450 °C appears to be the best conditions for the development of TiO2 and ZnO crystals leading to better photocatalytic activity. 相似文献
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Scientometrics - This research letter discusses whether Arab Spring explains the changes in research productivity and impact of Arab countries by identifying non-sociopolitical factors that can be... 相似文献
1000.
Jung Youngmi Kim Inyoung Mannaa Mohamed Kim Jinnyun Wang Sihyung Park Inmyoung Kim Jieun Seo Young-Su 《Food science and biotechnology》2019,28(1):261-267
Food Science and Biotechnology - Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver disorders. Possible links have been recently found between the gut-microbiota and the host... 相似文献