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991.
Pezhman Kazemi Mohammad Peydayesh Alireza Bandegi Toraj Mohammadi Omid Bakhtiari 《Chemical Engineering Research and Design》2014
Phenols pose a risk to the environment and to human health. Phenol and its derivatives are toxic pollutants, frequently found in surface and tap waters, and in aqueous effluents from various manufacturing processes. In this paper, an experimental study regarding transport of phenol through a supported liquid membrane (SLM) using tributyl phosphate (TBP) and sesame oil as liquid membrane (LM) was performed. Factors affecting permeation of phenol such as initial phenol concentration, carrier concentration, feed phase pH and stripping phase concentration were analyzed using Taguchi method. Optimal experimental condition of phenol transport was obtained using analysis of variance (ANOVA) after 7 h extraction (feed concentration: 200 mg/L; carrier concentration (%TBP): 40%; feed pH: 2; strip phase concentration: 1.1 M). Mass transfer coefficient for this system was evaluated, and compared with similar works, and it was shown that it has the highest mass transfer rate. In addition to transport study, stability of the membrane was investigated by examination of stripping phase concentration, carrier concentration and salt concentration effects. 相似文献
992.
Regulation of the Stem Cell–Host Immune System Interplay Using Hydrogel Coencapsulation System with an Anti‐Inflammatory Drug
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Alireza Moshaverinia Chider Chen Xingtian Xu Sahar Ansari Homayoun H. Zadeh Scott R. Schricker Michael L. Paine Janet Moradian‐Oldak Ali Khademhosseini Malcolm L. Snead Songtao Shi 《Advanced functional materials》2015,25(15):2296-2307
The host immune system is known to influence mesenchymal stem cell (MSC)‐mediated bone tissue regeneration. However, the therapeutic capacity of hydrogel biomaterial to modulate the interplay between MSCs and T‐lymphocytes is unknown. Here it is shown that encapsulating hydrogel affects this interplay when used to encapsulate MSCs for implantation by hindering the penetration of pro‐inflammatory cells and/or cytokines, leading to improved viability of the encapsulated MSCs. This combats the effects of the host pro‐inflammatory T‐lymphocyte‐induced nuclear factor kappaB pathway, which can reduce MSC viability through the CASPASE‐3 and CASPASE‐8 associated proapoptotic cascade, resulting in the apoptosis of MSCs. To corroborate rescue of engrafted MSCs from the insult of the host immune system, the incorporation of the anti‐inflammatory drug indomethacin into the encapsulating alginate hydrogel further regulates the local microenvironment and prevents pro‐inflammatory cytokine‐induced apoptosis. These findings suggest that the encapsulating hydrogel can regulate the MSC‐host immune cell interplay and direct the fate of the implanted MSCs, leading to enhanced tissue regeneration. 相似文献
993.
Alireza Kazemipour Martin Hudlička Robert Dickhoff Mohammed Salhi Thomas Kleine-Ostmann Thorsten Schrader 《Journal of Infrared, Millimeter and Terahertz Waves》2014,35(9):720-731
Rising progress of mm-wave technology in spectroscopy, remote-sensing and its prospective application in communications requires accurate radiation beam characterization in quasi-optical systems. Gaussian approximation is a well-known practical model at optical and infrared wavelengths, and here we try to show the performance and limits of this method for the horn antenna as a classical mm-wave radiation source. This approach provides a compact and more practical analytical tool to design and optimize quasi-optical systems, compared to electromagnetic (EM) full-wave solutions. The radiation pattern (beam shape) and the phase distribution are studied analytically, both with the EM full-wave method and Gaussian approximation. Comparative results with measurements are presented to verify the analytical process and show the feasibility of the method for conventional horns. 相似文献
994.
A novel micromechanical approach is used to study the fatigue failure of unidirectional polymer matrix composites subject to off-axis loading. The main advantage of the present micromechanical model lies in its ability to give closed form solutions for the effective nonlinear response of unidirectional composites and to predict the material response to any combination of shear and normal loading. The fatigue failure criterion is expressed in terms of the fatigue failure functions of the constituent materials. The micromechanical model is also used to calculate these fatigue failure functions from the knowledge of the S–N diagrams of the composite material in longitudinal, transverse, and shear loadings; thus, eliminating the need for any further experimentation. Unlike previous works, the present study accounts for the viscoelasticity of the matrix material rendering it the capability of modeling creep damage accumulation in high-temperature composite materials. The results are found to be in good agreement with the literature. In particular, for higher off-axis angles, the results are seen to be in better concurrence with the experimental data compared to when the effect of viscoelasticity is overlooked. The present approach is also capable of accounting for the strain evolution due to viscoelasticity of the matrix material. 相似文献
995.
25th Anniversary Article: Double Emulsion Templated Solid Microcapsules: Mechanics And Controlled Release
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Sujit S. Datta Alireza Abbaspourrad Esther Amstad Jing Fan Shin‐Hyun Kim Mark Romanowsky Ho Cheung Shum Bingjie Sun Andrew S. Utada Maike Windbergs Shaobing Zhou David A. Weitz 《Advanced materials (Deerfield Beach, Fla.)》2014,26(14):2205-2218
How droplet microfluidics can be used to fabricate solid‐shelled microcapsules having precisely controlled release behavior is described. Glass capillary devices enable the production of monodisperse double emulsion drops, which can then be used as templates for microcapsule formation. The exquisite control afforded by microfluidics can be used to tune the compositions and geometrical characteristics of the microcapsules with exceptional precision. The use of this approach to fabricate microcapsules that only release their contents when exposed to a specific stimulus – such as a change in temperature, exposure to light, a change in the chemical environment, or an external stress – only after a prescribed time delay, and at a prescribed rate is reviewed. 相似文献
996.
Alireza Arab Solghar F. P. Brito Morteza Abdolzadeh Ali Farajpour 《Lubrication Science》2015,27(2):83-102
The thermohydrodynamic characteristics of journal bearings with two axial grooves are investigated by means of computational fluid dynamics technique. The equations governing the problem are those of continuity, momentum and energy, which are discretised using hybrid scheme and solved simultaneously employing the SIMPLE algorithm. The novelty of the present model resides mainly in the fact that it was able to accurately predict the temperature profile of twin groove plain hydrodynamic journal bearings to a degree that, to the authors' knowledge, has not been obtained so far, particularly in the inactive portion of the bearing and in the vicinity of grooves. This has been accomplished by performing a computational fluid dynamics analysis in which no relevant simplifications have been made to the governing equations along with the use of a detailed cavitation algorithm. This allowed to perform a reliable assessment of the influence of lubricant feeding conditions and to confirm their relevance for bearing design. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
997.
Zomordikhani Zahed Attar Mohammadmahdi Jahangiri Alireza Barati Farzan 《Journal of Mechanical Science and Technology》2020,34(9):3911-3918
Journal of Mechanical Science and Technology - The objective of this study is to examine the role of blood perfusion in magnetic fluid hyperthermia by drug delivery. Although increasing blood... 相似文献
998.
Sergey Gortschakow Diego Gonzalez Steffen Franke Alireza Khakpour Ralf Methling Dirk Uhrlandt Klaus-Dieter Weltmann 《真空研究与实践》2020,32(2):14-19
Advanced optical diagnostics of vacuum arc plasma for switching applications Vacuum technology provides environmentally compatible and emission-free solutions for switching in power grids. A high number of operations under standard load conditions, safe and reproducible short-circuit current interruption capability, and maintenance-free operation are few examples of advantages of vacuum circuit breakers. Further development of such devices requires fundamental knowledge about the switching process and interaction of materials used with the working medium – the vacuum arc plasma. The optical diagnostics offers numerous methods for the characterization of the arc plasma and surrounding components, like e.g. electrodes and chamber walls. Studies of plasma and electrode phenomena by combination of optical and electrical diagnostics allow for material qualification, choice of design and arc extinguishing mechanisms. 相似文献
999.
具有适应性突变和惯性权重的粒子群优化(PSO)算法及其在动态系统参数估计中的应用 总被引:6,自引:0,他引:6
ALFI Alireza 《自动化学报》2011,37(5):541-549
An important problem in engineering is the unknown parameters estimation in nonlinear systems. In this paper, a novel adaptive particle swarm optimization (APSO) method is proposed to solve this problem. This work considers two new aspects, namely an adaptive mutation mechanism and a dynamic inertia weight into the conventional particle swarm optimization (PSO) method. These mechanisms are employed to enhance global search ability and to increase accuracy. First, three well-known benchmark functions namely Griewank, Rosenbrock and Rastrigrin are utilized to test the ability of a search algorithm for identifying the global optimum. The performance of the proposed APSO is compared with advanced algorithms such as a nonlinearly decreasing weight PSO (NDWPSO) and a real-coded genetic algorithm (GA), in terms of parameter accuracy and convergence speed. It is confirmed that the proposed APSO is more successful than other aforementioned algorithms. Finally, the feasibility of this algorithm is demonstrated through estimating the parameters of two kinds of highly nonlinear systems as the case studies. 相似文献
1000.
Tube-based Model Reference Adaptive Control for Vibration Suppression of Active Suspension Systems
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Yashar Mousavi Alireza Alfi Ibrahim Beklan Kucukdemiral Afef Fekih 《IEEE/CAA Journal of Automatica Sinica》2022,9(4):728-731
<正>Dear editor,With the developments of industrial automation in recent years,vehicle suspension systems have received a great deal of attention in industry and academia due to their critical role in the chassis performance of vehicles [1]. The suspension system is expected to guarantee the vehicle’s maneuverability and provide satisfactory ride comfort by absorbing the vibrations arising from the road surface excitations and ensuring road-holding capability and suspension safety. 相似文献