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A novel microfluidic droplet generator is proposed, which can control the droplet size through turning an integrated micrometer head with ease, and the size of the produced micro-droplet can be automatically and real-time monitored by an open-sourced software and off-the-shelf hardware. 相似文献
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The evaluation and interpretation of the behavior of construction materials under fire conditions have been complicated. Over the last few years, artificial intelligence (AI) has emerged as a reliable method to tackle this engineering problem. This review summarizes existing studies that applied AI to predict the fire performance of different construction materials (e.g., concrete, steel, timber, and composites). The prediction of the flame retardancy of some structural components such as beams, columns, slabs, and connections by utilizing AI-based models is also discussed. The end of this review offers insights on the advantages, existing challenges, and recommendations for the development of AI techniques used to evaluate the fire performance of construction materials and their flame retardancy. This review offers a comprehensive overview to researchers in the fields of fire engineering and material science, and it encourages them to explore and consider the use of AI in future research projects. 相似文献
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Leiqing Hu Sankhajit Pal Hien Nguyen Vinh Bui Haiqing Lin 《Journal of polymer science. Part A, Polymer chemistry》2020,58(18):2467-2481
Over the last two decades, polymers with superior H2/CO2 separation properties at 100–300 °C have gathered significant interest for H2 purification and CO2 capture. This timely review presents various strategies adopted to molecularly engineer polymers for this application. We first elucidate the Robeson's upper bound at elevated temperatures for H2/CO2 separation and the advantages of high-temperature operation (such as improved solubility selectivity and absence of CO2 plasticization), compared with conventional membrane gas separations at ~35 °C. Second, we describe commercially relevant membranes for the separation and highlight materials with free volumes tuned to discriminate H2 and CO2, including functional polymers (such as polybenzimidazole) and engineered polymers by cross-linking, blending, thermal treatment, thermal rearrangement, and carbonization. Third, we succinctly discuss mixed matrix materials containing size-sieving or H2-sorptive nanofillers with attractive H2/CO2 separation properties. 相似文献
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Ho Van Doanh Phan Bao Quoc Hieu Pham Ngoc Son Dao Van Hoang Tam Hoang Duc Ho Manh Dung 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(3):1361-1365
Journal of Radioanalytical and Nuclear Chemistry - To keep the accredited category for the gamma spectrometry test in our laboratory, the efficiency curves of a HPGe detector for soil sample in... 相似文献
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Differential Equations - We consider compact difference schemes of approximation order $$4+2 $$ on a three-point spatial stencil for the Klein–Gordon equations with constant and variable... 相似文献
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Le Quang Thuy Bui Thi Thanh Nguyen Thi Toan 《Journal of Optimization Theory and Applications》2017,173(2):421-442
Motivated by our recent works on optimality conditions in discrete optimal control problems under a nonconvex cost function, in this paper, we study second-order necessary and sufficient optimality conditions for a discrete optimal control problem with a nonconvex cost function and state-control constraints. By establishing an abstract result on second-order optimality conditions for a mathematical programming problem, we derive second-order necessary and sufficient optimality conditions for a discrete optimal control problem. Using a common critical cone for both the second-order necessary and sufficient optimality conditions, we obtain “no-gap” between second-order optimality conditions. 相似文献