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131.
Hashemi Abbas Gollo Mohammad Hoseinpour Seyedkashi S. M. Hossein 《Journal of Mechanical Science and Technology》2016,30(5):2217-2224
Journal of Mechanical Science and Technology - An adaptive Finite element analysis (FEA) was proposed in this paper for the industrial design of bimetal conical-cylindrical cup hydroforming.... 相似文献
132.
Hosein Ghaffarzadeh Amir Hossein Ghaffari T. Y. Yang 《The Structural Design of Tall and Special Buildings》2019,28(1)
In this paper, the effectiveness of the fuzzy sliding mode control strategy on three‐dimensional benchmark building with smart base isolation under seismic excitation has been examined. One of the appropriate control theories for such this nonlinear system is the sliding mode control theory; discontinuous sliding mode theory has weakness such as chattering phenomena. In this paper, we used a combination of fuzzy logic and sliding mode theory for the deletion of this defect. The proposed control theory has been scrutinized by applying on lately developed nonlinear three‐dimensional base‐isolated benchmark building. This building because of the three‐dimensional nature, coalescing of lateral and torsional responses, continuity of responses of the superstructure, and base is modeled with three degrees of freedom on every floor. In this building eight actuators assigned only at the base level and in the two directions (x, y). In other words, 16 actuators are located underneath the structure. Furthermore, the base isolation system has been modeled by considering lateral coupled equations for a better examination of the performance of the system. The results indicate that reduction of control performance is remarkable. Also, utilizing proposed control theory can decrease the responses of building in two main directions and, particularly, in the rotational degree of freedom. 相似文献
133.
Atashi Hossein Hajisafari Mohsen Rezaeian Fatemeh Parnian Mohammad Javad 《国际煤炭科学技术学报(英文)》2019,6(1):27-36
International Journal of Coal Science & Technology - The modeling of hydrocarbon selectivity and CO conversion of the Fischer–Tropsch synthesis over Fe–Ni/Al2O3 catalyst by using... 相似文献
134.
Khani Ali Eskandani Morteza Derakhshankhah Hossein Soleimani Khadijeh Nakhjavani Sattar Akbari Massoumi Bakhshali Jahanban-Esfahlan Rana Moloudi Kave Jaymand Mehdi 《Journal of Polymer Research》2022,29(4):1-10
Journal of Polymer Research - Derivatives of formyl pyrazole were synthesized by the reaction of acetophenone, 4-methyl acetophenone, 3-acetyl furan, 3-acetyl thiophen and phenyl hydrazine... 相似文献
135.
Synthesis of biocompatible and degradable microspheres based on 2‐hydroxyethyl methacrylate via microfluidic method 下载免费PDF全文
Mohammad Tarameshlou Seyed Hassan Jafari Iraj Rezaeian Hossein Ali Khonakdar 《应用聚合物科学杂志》2014,131(20)
Monodisperse poly(2‐hydroxyethyl methacrylate), p‐HEMA, microspheres in size ranging from 16 to 340 (μm) were synthesized by in situ emulsion photopolymerization of HEMA monomer with polyethylene glycol diacrylate (p‐EGDA) by means of a three‐dimensional microfluidic flow‐focusing device. An aqueous solution of HEMA, p‐EGDA as chain extender and UV‐photoinitiator serving as dispersed phase formed microdroplets in a continuous oil phase mainly consisting of n‐heptane. A downward coaxial orifices design in the device led to confinement of the reaction admixtures thread to central axis of the microchannels. This design strategy could solve the wetting problem of dispersed phase with the microchannels leading to a successful production of monodisperse microspheres with size variation of less than 4%. The effects of concentration of p‐EGDA, surfactant, and flow rate ratios on microsphere size were examined. It was observed that increasing the concentration of p‐EGDA slightly increases the size whereas increasing the flow rate ratios of continuous to dispersed phase effectively decreases the size of microspheres. The rapid continuous synthesis of p‐HEMA based microspheres via the microfluidic route with reliable control over size, size distribution, and composition opens new doors for mass production of biocompatible and degradable polymeric microspheres for enormous biotechnological applications. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40925. 相似文献
136.
137.
Mohammad Soheilmoghaddam Pooria Pasbakhsh Mat Uzir Wahit Hossein Cheraghi Bidsorkhi Raheleh Heidar Pour Wong Tuck Whye R.T. De Silva 《Polymer》2014
Green nanocomposites of regenerated cellulose/exfoliated graphite nanosheets films with low nanofiller loadings were prepared using environmentally benign 1-butyl-3-methylimidazolium chloride (BMIMCl) ionic liquid. X-ray diffraction revealed well developed intercalated nanocomposites. The tensile strength and Young's modulus of the prepared nanocomposites were increased by 97.5% and 172% respectively when 0.75 wt.% and 1 wt.% exfoliated graphite nanosheets were added. The results were validated using the Halpin–Tsai model. The exfoliated graphite nanosheets were unidirectionally aligned in the regenerated cellulose parallel to the surface of the nanocomposites as revealed by transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM). Also, the TEM and FESEM revealed uniform dispersion of the exfoliated graphite nanosheets and good interaction between the nanofillers and the matrix. The addition of the exfoliated graphite nanosheets enhanced the thermal stability and reduced the water absorption and diffusivity of the nanocomposites. 相似文献
138.
Amir Saeid Pakdel Mohammad Reza Saeb Hossein Abedini Hossein Ali Khonakdar Regine Boldt 《Polymer Bulletin》2014,71(10):2487-2506
This work is targeted to study emulsion polymerization of vinyl chloride monomer (VCM) using experimental and mathematical methods. To fulfill this goal, a computer code was developed on the basis of zero–one population balance by which the effects of initiator and emulsifier concentration on the evolution of VCM conversion were investigated in the course of polymerization. The model was also trained to capture the coagulation of the particles. This enabled to adopt a reliable way of evaluating the particle size distribution (PSD). In particular, the rates of homogeneous and micellar nucleation mechanisms were simulated and reasonably predicted alterations in the PSD and the number of polymer particles under the influence of aforementioned parameters. The results from modeling were satisfactorily consistent with the experimental outputs and obviously visualized the impact of initiator and surfactant concentration on the PSD of the prepared PVC latexes. 相似文献
139.
Ahmad Hosseini-Bandegharaei Mohammad Karimzadeh Masoud Sarwghadi Aliasghar Heydarbeigi Seyyed Hossein Hosseini Mehdi Nedaie Hassan Shoghi 《Chemical Engineering Research and Design》2014
Adsorption of Pb(II) ion by a novel extractant-impregnated resin, EIR, was studied as a function of various experimental parameters using batch adsorption experiments. The new EIR was prepared by impregnating gallocyanine (GCN) onto Amberlite XAD-16 resin beads. The EIR was characterized by nitrogen analysis and SEM micrographs. The new EIR showed excellent selectivity factor values (α) for Pb(II) adsorption respect to other metal ions. The effects of some chemical and physical variables were evaluated and the optimum conditions were found for Pb(II) removal from aqueous solutions. The equilibrium adsorption isotherm was fitted with the Langmuir adsorption model. The maximum adsorption capacity (qmax) of EIR for Pb(II) ions was found to be 367.92 mg g−1. The kinetic studies showed that the intra-particle diffusion is the rate-controlling step. Also, the intra-particle diffusion coefficients, Dip values, were of the order of 10−12 m2 s−1. The values of enthalpy (ΔH°) were positive, which confirms the endothermic nature of adsorption process. Also, the positive entropy changes (ΔS°) were showed that the randomness increased along with the adsorption process. In addition, the obtained negative values of Gibbs free energy (ΔG°) indicated feasible and spontaneous nature of the adsorption process at different temperatures. The new adsorbent was very stable so that it can be successfully used for many consecutive cycles without significant loss in its adsorption capacity. 相似文献
140.
Recent Developments in Predicting Impact and Shock Sensitivities of Energetic Materials (英) 总被引:1,自引:0,他引:1
Mohammad Hossein Keshavarz Arash Shokrolahi Karim Esmailpoor Abbas Zali Hamid Reza Hafizi Jamshid Azarniamehraban 《含能材料》2008,16(1):113-120
Empirical, quantum mechanical and artificial neural network methods are three usual methods in recent years that were used to predict sensitivity of different classes of high explosives. Some recent developments in predicting sensitivity by various methods are reviewed and discussed for various classes of energetic materials. 相似文献