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排序方式: 共有1559条查询结果,搜索用时 15 毫秒
61.
Ali Shirazi Mehdi Aminyavari Behzad Najafi Fabio Rinaldi Majid Razaghi 《International Journal of Hydrogen Energy》2012
In this article, an internal-reforming solid oxide fuel cell–gas turbine (IRSOFC–GT) hybrid system is modeled and analyzed from thermal (energy and exergy), economic, and environmental points of view. The model is validated using available data in the literature. Utilizing the genetic algorithm optimization technique, multi-objective optimization of modeled system is carried out and the optimal values of system design parameters are obtained. In the multi-objective optimization procedure, the exergy efficiency and the total cost rate of the system (including the capital and maintenance costs, operational cost (fuel cost), and social cost of air pollution for CO, NOx, and CO2) are considered as objective functions. A sensitivity analysis is also performed in order to study the effect of variations of the fuel unit cost on the Pareto optimal solutions and their corresponding design parameters. The optimization results indicate that the final optimum design chosen from the Pareto front results in exergy efficiency of 65.60% while it leads to total cost of 3.28 million US$ year−1. It is also demonstrated that the payback time of the chosen design is 6.14 years. 相似文献
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63.
Aliakbar Jafarzadeh Tahmineh Ahmadi Majid Taghian Dehaghani Kamran Mohemi 《Russian Journal of Non-Ferrous Metals》2018,59(4):458-464
In this study, a nano-composite composed of gelatin as the matrix and Si-Mg-FA nano-particles as an additive was deposited on the AZ31 Mg alloy via dip coating method. In addition, a coating composed of MgO, MgSiO3 and Mg2SiO4 phases was applied on the AZ31 Mg alloy by anodizing process. It was found that the Nano-composite coating with a uniform distribution of nano-particles within the gelatin matrix with the thickness of about 9 µm was dense, crack-free and uniform whereas the surface of anodized layer was relatively coarse due to the presence of flaws and micro-cracks. The surface morphology, EDS analysis and FTIR results revealed the ability of nano-composite coated specimen to form the bone-like apatite. Due to the presence of aforementioned phases and special surface features, the anodized specimen possessed higher and lower corrosion resistance than uncoated and nano-composite coated specimens, respectively. The passive coating resistances (RCT) of nano-composite, anodized specimen and uncoated samples were 2164, 1449 and 1024 Ω cm2, respectively. 相似文献
64.
Journal of Mechanical Science and Technology - Water permeation dynamics through hourglass-shaped nanopore is addressed by using Molecular dynamics (MD) simulations. The objective of this research... 相似文献
65.
66.
Abbas Syed Zeeshan Ibrahim Haroon Khan Majid 《Multimedia Tools and Applications》2021,80(17):26069-26091
Multimedia Tools and Applications - In this article, we have designed a new information confidentiality mechanism based on the combination of Blowfish encryption algorithm along with Henon and Chen... 相似文献
67.
Taheri Mostafa Zhang Chongqi Berardehi Zahra Rasooli Chen Yucheng Roohi Majid 《Multimedia Tools and Applications》2022,81(17):24167-24197
Multimedia Tools and Applications - Synchronization of different Chaotic dynamical systems is one of the main issues in engineering which has a lot of applications in applied sciences like secure... 相似文献
68.
Majid Azarang Mehran Sookhakian Mousa Aliahmad Masoumeh Dorraj Wan Jeffrey Basirun Boon Tong Goh Yatimah Alias 《International Journal of Hydrogen Energy》2018,43(32):14905-14914
Nitrogen-doped graphene-ZnS composite (NG-ZnS) was synthesized by thermal treatment of graphene-ZnS composite (G-ZnS) in NH3 medium. In the second step, the as-synthesized samples were deposited on indium tin oxide glass (ITO) by electrophoretic deposition for photocatalytic hydrogen evolution reaction. The as-prepared NG-ZnS-modified ITO electrode displayed excellent photocatalytic activity, rapid transient photocurrent response, superior stability and high recyclability compared to the pure ZnS and G-ZnS-modified ITO electrode due to the synergy between the photocatalytic activity of ZnS nanorods and the large surface area and high conductivity of N-graphene. 相似文献
69.
Propane dehydrogenation on a commercial Pt-Sn/Al2O3 catalyst in a Pd-Ag membrane reactor is considered. A mathematical model is developed to evaluate the performance of the catalytic membrane reactor for the process of propane dehydrogenation. Design and operating conditions are systematically evaluated for key performance metrics such as propane conversion, propylene selectivity, hydrogen selectivity, and hydrogen recovery under different operating conditions. The results confirm that the high performance of the membrane reactor is related to the continuous removal of hydrogen from the reaction zone to shift the reaction equilibrium towards the formation of more propylene and hydrogen. 相似文献
70.