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排序方式: 共有4081条查询结果,搜索用时 234 毫秒
991.
992.
Ziqiang Cheng Kevin M. Tenny Alberto Pizzolato Antoni Forner-Cuenca Vittorio Verda Yet-Ming Chiang Fikile R. Brushett Reza Behrou 《American Institute of Chemical Engineers》2022,68(4):e17540
High-dimensional models typically require a large computational overhead for multiphysics applications, which hamper their use for broad-sweeping domain interrogation. Herein, we develop a modeling framework to capture the through-plane fluid dynamic response of electrodes and flow fields in a redox flow cell, generating a computationally inexpensive two-dimensional (2D) model. We leverage a depth-averaging approach that also accounts for variations in out-of-plane fluid motion and departures from Darcy's law that arise from averaging across three-dimensions (3D). Our resulting depth-averaged 2D model successfully predicts the fluid dynamic response of arbitrary in-plane flow field geometries, with discrepancies of <5% for both maximum velocity and pressure drop. This corresponds to reduced computational expense, as compared to 3D representations (<1% of duration and 10% of RAM usage), providing a platform to screen and optimize a diverse set of cell geometries. 相似文献
993.
Maximilian Moser Johannes Gladisch Sarbani Ghosh Tania Cecilia Hidalgo James F. Ponder Jr. Rajendar Sheelamanthula Quentin Thiburce Nicola Gasparini Andrew Wadsworth Alberto Salleo Sahika Inal Magnus Berggren Igor Zozoulenko Eleni Stavrinidou Iain McCulloch 《Advanced functional materials》2021,31(26):2100723
Electrochemically induced volume changes in organic mixed ionic-electronic conductors (OMIECs) are particularly important for their use in dynamic microfiltration systems, biomedical machinery, and electronic devices. Although significant advances have been made to maximize the dimensional changes that can be accomplished by OMIECs, there is currently limited understanding of how changes in their molecular structures impact their underpinning fundamental processes and their performance in electronic devices. Herein, a series of ethylene glycol functionalized conjugated polymers is synthesized, and their electromechanical properties are evaluated through a combined approach of experimental measurements and molecular dynamics simulations. As demonstrated, alterations in the molecular structure of OMIECs impact numerous processes occurring during their electrochemical swelling, with sidechain length shortening decreasing the number of incorporated water molecules, reducing the generated void volumes and promoting the OMIECs to undergo different phase transitions. Ultimately, the impact of these combined molecular processes is assessed in organic electrochemical transistors, revealing that careful balancing of these phenomena is required to maximize device performance. 相似文献
994.
Mercedes Jiménez-Rosado Adrián Martín María Alonso-González Antonio Guerrero Alberto Romero 《Polymer Engineering and Science》2020,60(9):2285-2291
The excessive use of fertilizers in horticulture applications generates subsoil and groundwater contamination due to their high solubility. A possible solution to this problem is the incorporation of nutrients in biodegradable matrices, allowing nutrients to be released in a controlled manner depending on the needs of the crops. The principal objective of this work was the evaluation of the incorporation of different salts into soy protein-based matrices to develop devices that could release micronutrients in a controlled manner. Thus, the processability of matrices with different incorporated salts such as zinc sulfate heptahydrate (ZnSO4·7H2O), zinc sulfate monohydrate (ZnSO4·H2O), zinc carbonate (ZnCO3), and zinc perchlorate (Zn(ClO3)2), as well as their integrity and functionality have been evaluated. Results show the great potential of soy protein-based matrices for the incorporation of micronutrients such as zinc. However, salt incorporation has a detrimental effect on the water uptake capacity of the matrices. 相似文献
995.
996.
de Freitas Veneroso João Mateus Dias Marlon Ueda Alberto Ribas Sabir Ribeiro-Neto Berthier Ziviani Nivio de Souza e Silva Edmundo 《Scientometrics》2019,121(3):1269-1291
Scientometrics - The notions of reputation and popularity in academia are critical for taking decisions on research grants, faculty position tenure, and research excellence awards. These notions... 相似文献
997.
Fernandes Maria Clara Yildirim Onur Woo Sungmin Vargas Hebert Alberto Hricak Hedvig 《Magma (New York, N.Y.)》2022,35(4):503-521
Magnetic Resonance Materials in Physics, Biology and Medicine - There has been an increasing role of magnetic resonance imaging (MRI) in the management of prostate cancer. MRI already plays an... 相似文献
998.
Chacón Edgar Cruz Salazar Luis Alberto Cardillo Juan Paredes Astudillo Yenny Alexandra 《Journal of Intelligent Manufacturing》2021,32(7):2061-2081
Journal of Intelligent Manufacturing - Industry 4.0 (I4.0) brings together new disruptive technologies, increasing future factories’ productivity. Indeed, the control of production processes... 相似文献
999.
Carlos Lax Ghizlane Tahiri Jos Alberto Patio-Medina Jos T. Cnovas-Mrquez Jos A. Prez-Ruiz Macario Osorio-Concepcin Eusebio Navarro Silvia Calo 《International journal of molecular sciences》2020,21(24)
RNA interference (RNAi) was discovered at the end of last millennium, changing the way scientists understood regulation of gene expression. Within the following two decades, a variety of different RNAi mechanisms were found in eukaryotes, reflecting the evolutive diversity that RNAi entails. The essential silencing mechanism consists of an RNase III enzyme called Dicer that cleaves double-stranded RNA (dsRNA) generating small interfering RNAs (siRNAs), a hallmark of RNAi. These siRNAs are loaded into the RNA-induced silencing complex (RISC) triggering the cleavage of complementary messenger RNAs by the Argonaute protein, the main component of the complex. Consequently, the expression of target genes is silenced. This mechanism has been thoroughly studied in fungi due to their proximity to the animal phylum and the conservation of the RNAi mechanism from lower to higher eukaryotes. However, the role and even the presence of RNAi differ across the fungal kingdom, as it has evolved adapting to the particularities and needs of each species. Fungi have exploited RNAi to regulate a variety of cell activities as different as defense against exogenous and potentially harmful DNA, genome integrity, development, drug tolerance, or virulence. This pathway has offered versatility to fungi through evolution, favoring the enormous diversity this kingdom comprises. 相似文献
1000.
M.H. Alves G. Constantini A. Ianni E. F. A. Kimura Alberto Meda P.A.G. Piloto 《火与材料》2022,46(1):227-250
Double-stud light steel frame (LSF) walls provide an enhanced insulation performance when exposed to fire conditions. However, the behavior of different configurations of such assemblies under fire is not well understood. Thus, this study aimed to assess the fire resistance of non-load-bearing double-stud LSF walls subjected to ISO834 standard fire. The walls were lined with one or two type F gypsum plasterboards on each side, using cavity uninsulated or insulated with ceramic fiber. The experimental tests revealed that a wider cavity slows the heat transfer through the cross-section, delaying the temperature rise on the unexposed surfaces. The use of ceramic fiber insulation substantially increases the fire resistance of the wall and when the cavity is partially filled with this material, if the blanket is placed towards the exposed side, enhanced insulation fire resistance is achieved. Based on the finite element method, a numerical validation was conducted using a special hybrid approach that used experimental temperature values inside the cavities or insulation blankets. This approximation was essential to improve the numerical results. Also, the employment of an air layer, located at specific regions of the models, helped to improve the numerical results, introducing an extra thermal resistance. A new simplified approach was proposed based on the improved design model available in the literature, and the results obtained are consistent with the experimental results. The predicted insulation fire resistance of the numerical and simplified methods agreed well with the experimental results and useful information is supplied to support further numerical and experimental studies. 相似文献