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排序方式: 共有253条查询结果,搜索用时 11 毫秒
81.
Bulk Single Crystal‐Like Structural and Magnetic Characteristics of Epitaxial Spinel Ferrite Thin Films with Elimination of Antiphase Boundaries 下载免费PDF全文
Amit V. Singh Behrouz Khodadadi Jamileh Beik Mohammadi Sahar Keshavarz Tim Mewes Devendra Singh Negi Ranjan Datta Zbigniew Galazka Reinhard Uecker Arunava Gupta 《Advanced materials (Deerfield Beach, Fla.)》2017,29(30)
Spinel ferrite NiFe2O4 thin films have been grown on three isostructural substrates, MgAl2O4, MgGa2O4, and CoGa2O4 using pulsed laser deposition. These substrates have lattice mismatches of 3.1%, 0.8%, and 0.2%, respectively, with NiFe2O4. As expected, the films grown on MgAl2O4 substrate show the presence of the antiphase boundary defects. However, no antiphase boundaries (APBs) are observed for films grown on near‐lattice‐matched substrates MgGa2O4 and CoGa2O4. This demonstrates that by using isostructural and lattice‐matched substrates, the formation of APBs can be avoided in NiFe2O4 thin films. Consequently, static and dynamic magnetic properties comparable with the bulk can be realized. Initial results indicate similar improvements in film quality and magnetic properties due to the elimination of APBs in other members of the spinel ferrite family, such as Fe3O4 and CoFe2O4, which have similar crystallographic structure and lattice constants as NiFe2O4. 相似文献
82.
Iraj Kazeminezhad Azar Sadollahkhani 《Journal of Materials Science: Materials in Electronics》2016,27(5):4206-4215
In this study, ZnO nanoparticles were fabricated by co-precipitation method. The synthesized nanoparticles possessed monodispersity with the average size 20–30 nm. Since the industrial effluents may not be at neutral pH, the effect of pH on the rate of degradation is important and need to be considered. In order to investigate the effect of pH on ZnO nanoparticles photocatalytic activity, the photocatalytic degradation of Rose Bengal, Methylene blue, and Bromocresol green dyes, was studied with different pH values. It was observed that the adsorption of the dyes onto ZnO nanoparticles surface is strongly dependent on the pH of the solution which plays an important role in photocatalytic degradation. 相似文献
83.
Amiri Iraj S. Sorger Volker J. Ariannejad M. M. Ling Xi Ghasemi M. Yupapin P. 《Microsystem Technologies》2018,24(3):1673-1681
Microsystem Technologies - This paper reports on an approach for fabrication of micro-channels with nanometer thickness achieved by optimization of UV lithography processes. Rectangular... 相似文献
84.
Adel Nadjaran Toosi Farzad Khodadadi Rajkumar Buyya 《Concurrency and Computation》2016,28(13):3672-3690
Designing dynamic pricing mechanisms that efficiently price resources in line with a provider's profit maximization goal is a key challenge in cloud computing environments. Despite the large volume of research published on this topic, there is no publicly available software system implementing dynamic pricing for Infrastructure as a Service cloud spot markets. This paper presents the implementation of a framework called Spot instance pricing as a Service (SipaaS) that supports an auction mechanism to price and allocate virtual machine instances. SipaaS is an open‐source project offering a set of web services to price and sell virtual machine instances in a spot market resembling the Amazon EC2 spot instances. Cloud providers, who aim at utilizing SipaaS, should install add‐ons in their existing platform to make use of the framework. As an instance, we provide an extension to the Horizon – the OpenStack dashboard project – to employ SipaaS web services and to add a spot market environment to OpenStack. To validate and evaluate the system, we conducted an experimental study with a group of 10 users utilizing the provided spot market in a real environment. Results show that the system performs reliably in a practical test environment. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
85.
Maryam Torki Shahram Tangestaninejad Valiollah Mirkhani Majid Moghadam Iraj Mohammadpoor-Baltork Ahmad Reza Khosropour 《Journal of Inorganic and Organometallic Polymers and Materials》2013,23(4):923-929
Efficient alkene epoxidation with sodium periodate catalyzed by manganese(III) salophen supported on nanomagnetic materials is reported. First, the iron nanomagnets were silica coated, functionalized with imidazole and then manganese salophen was successfully bonded to their surface. The catalyst, [MnIII(salophen)Cl]@SiIm-Fe, was characterized by elemental analysis, FT-IR and UV/Vis spectroscopic techniques, SEM and ICP. The [MnIII(salophen)Cl]@SiIm-Fe was used for alkene epoxidation with sodium periodate at room temperature. Different aromatic and aliphatic terminal alkenes were epoxidized efficiently using sodium periodate as an oxidant. The effect of reaction parameters such as solvent and oxidant in the epoxidation of cis-cyclooctene was investigated. This new heterogenized epoxidation catalyst is easily recovered with a magnet and showed no appreciable loss of activity even after four consecutive runs. 相似文献
86.
Vahid Kayvanfar Iraj Mahdavi GH. M. Komaki 《The International Journal of Advanced Manufacturing Technology》2013,69(1-4):257-267
Job scheduling has always been a challenging task in modern manufacturing and the most real life scheduling problems which involves multi-criteria, multi-machine environments. In this research, the single-machine scheduling problem is studied in which job processing times are controllable, namely, they may vary within a specified interval. The goal of this research is to minimize total tardiness and earliness on a single machine, simultaneously. In this context, we first propose a mathematical model for the considered problem and then a net benefit compression–net benefit expansion heuristic is presented for obtaining the set of amounts of compression and expansion of jobs processing times in a given sequence. Two meta-heuristic approaches are then employed to solve medium-to-large-sized problems as local search methods. Thereafter, we apply a hybrid method based on our heuristic as well as these two meta-heuristics in order to obtain solutions with higher quality within lesser computational time. The addressed problem is NP-hard since the single machine total tardiness problem is already NP-hard. The computational results show that our proposed heuristics can effectively solve such Just-In-Time problem with a high-quality solution. 相似文献
87.
In this paper, the effect of electron confinement with magnetic fields in the multicusp ion source has been investigated. That is, electron confinement with magnetic fields plays a very important role for the generation of negative ions at plasma. Three-dimensional spatial distributions of electrons production are obtained for a multicusp ion source. The electron confinement of magnetic fields from various surface materials (such as Al2O3, Al, Au, Cu, w and stainless-steel) have been compared in a multicusp plasma source. The electron confinement effect becomes stronger with increasing N (the number of rows of permanent magnets) and using Al for plasma chamber wall material. The results of investigations have demonstrated good correspondence with experimental data, and therefore the adequacy of the developed approach and the possibility to build more effective source on this basis. 相似文献
88.
89.
Reza Hassanzadeh Esmaile Khorram Iraj Mahdavi Nezam Mahdavi-Amiri 《Applied Soft Computing》2011,11(1):551-560
We consider nonlinear optimization problems constrained by a system of fuzzy relation equations. The solution set of the fuzzy relation equations being nonconvex, in general, conventional nonlinear programming methods are not practical. Here, we propose a genetic algorithm with max-product composition to obtain a near optimal solution for convex or nonconvex solution set. Test problems are constructed to evaluate the performance of the proposed algorithm showing alternative solutions obtained by our proposed model. 相似文献
90.
In this paper we summarize our approach and findings in a point-free setting for recursive topology and recursive analysis. Recursive analysis has received intensive attention recently and our approach, while differing from those of other schools, does have connections to them. Here, we also present some of our findings on quantum and total recursive functions on the reals, introduce our classification of nonrecursive points, and remark on the connections between our work and the works of others. 相似文献