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1.
Eivazzadeh-Keihan Reza Noruzi Ehsan Bahojb Mehrban Sarah Fattahi Aliabadi Hooman Aghamirza Moghim Karimi Meghdad Mohammadi Adibeh Maleki Ali Mahdavi Mohammad Larijani Bagher Shalan Ahmed Esmail 《Journal of Materials Science》2022,57(6):3855-3891
Journal of Materials Science - Chitosan is one of the natural cationic polymers with unique properties such as non-toxicity, biodegradability, biocompatibility, environmentally friendly that has... 相似文献
2.
Pouria Fattahi Ali Borhan Mohammad Reza Abidian 《Advanced materials (Deerfield Beach, Fla.)》2013,25(33):4529-4529
3.
Fariborz Jolai Mehdi Foumani Reza Tavakoli-Moghadam Parviz Fattahi 《Journal of Intelligent Manufacturing》2012,23(5):1885-1891
In this paper, we study the problem of robotic cell scheduling with m machines with flexibility, load lock and swap assumptions. The robotic cell repetitively produces parts of identical types. We determine the cycle time of all 1-unit cycles in this type of robotic cell and present two new lower bounds for robot move cycles with load lock and swap, either there is flexibility or inflexibility. We also provide a new robot move cycle and prove that it dominates all classical robot move cycles considered in the existing literature of m-machine robotic cells. 相似文献
4.
Maryam Fattahi Hassan Abedini Mohammad Amin Anbaz 《Petroleum Science and Technology》2017,35(11):1117-1123
Favorable properties of aqueous solutions are improved with the addition of different materials for separation of hydrogen sulfide (H2S). Also, equilibrium data and available equations for solubility estimation of this gas are only valid for specific solutions and limited ranges of temperature and pressure. In this regard, a machine learning model based on Support vector machine (SVM) algorithm is proposed and developed with mixtures containing different amines and ionic liquids to predict H2S solubility over wide ranges of temperature (298–434.5 K), pressure (13–9319 kPa), overall mass concentration (3.82–100%) and mixture's apparent molecular weight (18.39–556.17 g/mol). The accuracy of the performance of this network was evaluated by regression analysis on calculated and experimental data, which had not been used in network training. 相似文献
5.
In this study, mathematical modeling of fixed-bed plasma reactor operated under isothermal condition was investigated. In this process, methane and acetylene were the inputted feed and ethane, ethylene, propylene, propane, i-butane, and n-butane were the output products. The amount of methane conversion obtained was 12.7% for the former feed, however, if pure methane was inputted this conversion rose to 13.8%. Furthermore, the plasma process enhanced the conversion as well as the selectivity toward the desired product and yield. In the present study, when methane and acetylene were fed at a molar ratio of CH4/C2H2 = 10 to the reactor, the selectivity of C2, C3, and C4 hydrocarbons was determined to be 30%, 24%, and 44%; respectively. A comparison between the thermal and the plasma process showed that the methane conversion and production yield in the plasma process were higher than in the thermal process under the same operating conditions. On the other hand, product selectivity in the plasma process was determined to be lower than that of the thermal process. Finally, results of the methane conversion processes in the plasma phase were compared with those available in the open literature. 相似文献
6.
Behdin Vahedi-Nouri Parviz Fattahi Reza Tavakkoli-Moghaddam Reza Ramezanian 《The International Journal of Advanced Manufacturing Technology》2014,73(5-8):601-611
In this paper, a more general version of the flow shop scheduling problem with the objective of minimizing the total flow time is investigated. In order to get closer to the actual conditions of the problem, some realistic assumptions including non-permutation scheduling, learning effect, multiple availability constraints, and release times are considered. It is assumed that the real processing time of each job on a machine depends on the position of that job in the sequence, and after processing a specified number of jobs at each machine, an unavailability period is occurring because of maintenance activities. Moreover, it is supposed that each job may not be ready for processing at time zero and may have a release time. According to these assumptions, a new mixed integer linear programming (MILP) model is proposed to formulate the problem. Due to the high complexity of the problem, a heuristic method and a simulated annealing algorithm are presented to find the nearly optimal solutions for medium- and large-sized problems. To obtain better and more robust solutions, the Taguchi method is used in order to calibrate the simulated annealing algorithm parameters. Finally, the computational results are provided for evaluating the performance and effectiveness of the proposed solution methods. 相似文献
7.
Simulation of Propane Dehydrogenation to Propylene in a Radial‐Flow Reactor over Pt‐Sn/Al2O3 as the Catalyst
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Seyed M. Miraboutalebi Leila Vafajoo Mohammad Kazemeini Moslem Fattahi 《化学工程与技术》2015,38(12):2198-2206
Catalytic paraffin dehydrogenation for manufacturing olefins is considered to be one of the most significant production routes in the petrochemical industries. A reactor kinetic model for the dehydrogenation of propane to propylene in a radial‐flow reactor over Pt‐Sn/Al2O3 as the catalyst was investigated here. The model showed that the catalyst activity was highly time dependent. In addition, the component concentrations and the temperature varied along the reactor radius owing to the occurring endothermic reaction. Moreover, a similar trend was noticed for the propane conversion as for the propylene selectivity, with both of them decreasing over the time period studied. Furthermore, a reversal of this trend was also revealed when the feed temperature was enhanced or when argon was added into the feed as an inert gas. 相似文献
8.
An analytical approach for short-fiber-reinforced composites is developed for three-dimensional (3D) elastic stress field distribution subjected to an applied axial load. Two sets of exact displacement solutions for matrix and fiber, which are respectively called far-field and transient solutions, are derived based on the theory of elasticity. The superposition state of these solutions are then used to obtain the analytical expressions for the 3D stress field components over the entire composite system, including the fiber end region, through the adding imaginary fiber technique. The fiber/matrix 3D stress field components fully satisfy the equilibrium and compatibility conditions in the theory of elasticity. The stress field components also satisfy the overall boundary, interface continuity, and axial force equilibrium conditions. The analytical results obtained are then validated by finite element method modeling. 相似文献
9.
We propose a (t, m)?(s, n) threshold quantum secret sharing protocol between multiparty (m members in group 1) and multiparty (n members in group 2) using a sequence of Greenberger–Horne–Zeilinger (GHZ) states, which is useful and efficient when the parties of communication are not all present. In the protocol, Alice prepares a sequence of GHZ states in one of the eight different states and sends the last two particles to the first agent while other members encode their information on the sequence via unitary transformations. Finally the last member in group 2 measures the qubits. It is shown that this scheme is safe. 相似文献
10.
M. Gazanfari M. Karimzadeh S. Ghorbani M. R. Sadeghi G. Azizi H. Karimi N. Fattahi Z. Karimzadeh 《Bulletin of Materials Science》2014,37(4):871-876
Aluminium nanoparticles (Al Nps) are synthesized using arc discharge method by applying direct current between aluminium electrodes in liquid environment without any use of vacuum equipment, heat exchangers, high temperatures furnaces and inert gases. After synthesis of Al Nps, in situ coating process on the nanoparticles was performed immediately. The effects of media on the yield and morphology of aluminium nanoparticles were investigated. Analysis result of the samples indicated that particle size was less than 30 nm, when 120 A/cm2 arc current was used. In addition, coating agent can affect arc velocity, arc stability, morphology and composition of the nanoparticles. Resultant nanoparticles were identified using X-ray powder diffraction (XRD), also their surface morphology was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and finally the accuracy of coating was assessed with infrared (IR) spectroscopy. 相似文献