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991.
tefan lu Ram Pratap Yadav Ali Arman Alireza Grayeli Korpi Dinara Sobola Mihai lu Sahare Rezaee Amine Achour Stanislav Jure
ka Mohsen Mardani 《真空研究与实践》2019,31(1):30-35
Fractal concepts are used to explore how different energies (10, 20 and 50 keV) and fluence of 5 × 1017 N+ cm?2 affect the morphology of nickel thin film. The nickel thin film with thickness of 100 nm is prepared by electron beam evaporation technique at room temperature on stainless steel (AISI 316) substrates. The nanoscale three‐dimensional (3‐D) surface micro‐morphologies are investigated by atomic force microscopy (AFM). Interface width is used to describe the surface height fluctuations. The autocorrelation function with height‐height correlation function give the quantitative data about the morphology of surface. The value of roughness exponent and fractal dimension is computed by height‐height correlation function. Fractal measure is an important analysis which provides fundamental insights into the texture characteristics and a direct way of testing their functional role. 相似文献
992.
993.
Seyyed Mohsen Beladi‐Mousavi Amir Masoud Pourrahimi Zdenk Sofer Martin Pumera 《Advanced functional materials》2019,29(5)
Phosphorene and antimonene, single‐ or few‐layered (FL) semiconductor materials, have recently attracted enormous attention due to their unique properties, provided by their extreme thinness. Here, a liquid‐phase exfoliation (LPE) procedure to prepare FL arsenene, another member of pnictogens, assisted by sonication and without any additional surfactant is reported. The exfoliation process is performed in various solvents. Among those, N‐methylpyrrolidone is found to provide the highest concentration of stable arsenene sheets. Spectroscopic and microscopic analyses confirm the formation of high‐quality few‐layer arsenene nanosheets with large lateral dimensions. An application of this material for construction of vapor sensor based on electrochemical impedance spectroscopy is demonstrated. The device detects selectively methanol or acetone vapors depending on the selected resonance frequency. The results are highly reproducible, and the vapor sensor has long‐term stability. 相似文献
994.
Many scientific and engineering applications require optimization methods to find more than one solution to multimodal optimization problems. This paper presents an experimental and computational investigation on the influences of the secondary mechanical processing with different reductions on the porosity, microstructure and mechanical properties of compocast high strength and highly uniform Al matrix composites. Multiple solutions to the problems are located and refined using a new particle swarm optimization (PSO) technique. The technique, NichePSO, extends the inherent unimodal nature of the standard PSO approach by growing multiple swarms from an initial particle population. Each subswarm represents a different solution or niche; optimized individually. The outcome of the NichePSO algorithm is a set of particle swarms, each representing a unique solution. The as-cast composite exhibited higher porosity content as compared with the composite in the rolled conditions. Furthermore, the tensile strength of the composites increased considerably by increasing the reduction ratio in the cold rolling process. 相似文献
995.
Preferential solvation of pomalidomide (PMD) was explored in dimethyl sulfoxide (DMSO)-dimethylformamide (DMF), DMSO-tetrahydrofuran (THF), DMSO-methanol (MeOH), DMSO-isopropanol, DMSO-water, water-DMF, water-THF, water-MeOH, and water–isopropanol binary mixed solvents at 298.15 K. Bosch-Rose model was utilized to determine the electronic transition energies (ET) and other preferential solvation parameters, describing solute-solute and solute-solvent interactions. We found that λmax situation shifted with dielectric constant of the pure solvents meaningfully. According to the obtained results, ET enhanced and λmax shifted to the lower wavelengths as the percentage of DMSO decreased in the binary mixtures, remarking the important role of DMSO for stabilizing the excited state (π⁎) of PMD chromophore via efficient intermolecular solute-solvent interactions. In addition, the aqueous binary systems showed an optimum point for the ET values as the percentage of water changed in the solutions. The local mole fraction of the solvents in the cybotactic region was also estimated to describe the specific and non-specific interactions in the systems. 相似文献
996.
Pattern Analysis and Applications - The curse of dimensionality in high-dimensional data is one of the major challenges in data clustering. Recently, a considerable amount of literature has been... 相似文献
997.
998.
Leila Gholami Reza Kazemi Oskuee Mohsen Tafaghodi Abouzar Ramezani Farkhani Majid Darroudi 《Ceramics International》2018,44(8):9263-9268
Superparamagnetic iron oxide (Fe3O4) nanoparticles (SPIONs) were synthesized by co-precipitation using polyvinyl alcohol (PVA) as a capping agent under alkaline condition. The produced X-ray diffraction (XRD) pattern evidenced the presence of peaks corresponding to the inverse spinel structure of the prepared SPIONs. Debye-Scherrer and field emission scanning microscopy (FESEM) showed the prepared SPIONs to be well-defined with about <?50?nm size. Likewise, the superparamagnetic properties of the SPIONs measured by Vibrating Sample Magnetometer (VSM) showed high saturation magnetization (~ 65.36?emu/g). The in vitro cytotoxicity studies on Neuro2A and HUVEC cells have mentioned low toxic and non-toxic SPIONs, respectively in a range of concentrations (1.17–150?μg/ml), thus, we reckon that the synthesized SPIONs will have persistent utilization in different fields of medical applications. 相似文献
999.
Seyed Mohsen Shahandashti Saiedeh N. Razavi Lucio Soibelman Mario Berges Carlos H. Caldas Ioannis Brilakis Jochen Teizer Patricio A. Vela Carl Haas James Garrett Burcu Akinci Zhenhua Zhu 《Canadian Metallurgical Quarterly》2011,137(10):863-869
Data fusion can be defined as the process of combining data or information for estimating the state of an entity. Data fusion is a multidisciplinary field that has several benefits, such as enhancing the confidence, improving reliability, and reducing ambiguity of measurements for estimating the state of entities in engineering systems. It can also enhance completeness of fused data that may be required for estimating the state of engineering systems. Data fusion has been applied to different fields, such as robotics, automation, and intelligent systems. This paper reviews some examples of recent applications of data fusion in civil engineering and presents some of the potential benefits of using data fusion in civil engineering. 相似文献
1000.