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151.
Copper‐substituted spinel Zn‐Mg ferrite nanoparticles as potential heating agents for hyperthermia
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Mohammad Ansari Ashkan Bigham Sayed Ali Hassanzadeh Tabrizi Hossein Abbastabar Ahangar 《Journal of the American Ceramic Society》2018,101(8):3649-3661
CuxZn0.5‐xMg0.5Fe2O4 (x = 0, 0.1, 0.2, 0.3, 0.4, 0.5) ferrite nanoparticles are synthesized via thermal treatment technique using polyvinyl alcohol (PVA) as a capping agent. The effect of Cu2+ ions substitution on the magnetic and structural properties of ZnMg ferrite nanoparticles is assessed. X‐ray diffraction (XRD) results prove the formation of spinel cubic ferrite with nanocrystalline structure. It is observed by increasing Cu2+ ions content in Cu2+‐substituted ZnMg ferrite samples, the lattice constant decreases. The field‐emission scanning electron microscopy (FESEM) micrographs indicate that all samples have sizes in nanometer scale with almost spherical morphology and ZnMg ferrite nanoparticles size is increased as the result of Cu2+ substitution. Magnetic data show that by increasing in Cu2+ content, the saturation magnetization (Ms) increases up to x = 0.3 and then declines with the addition of more Cu2+ ions in the samples. To assess the heat release of Cu2+‐substituted ZnMg ferrite nanoparticles, an alternating magnetic (AC) field is applied. The results show an upward trend for the samples in the temperature vs time chart, as a result of increasing in Ms of the samples. The Cu0.3Zn0.2Mg0.5Fe2O4 sample exhibits a temperature increase up to 43°C during 510 seconds in the exposure of 125 Oe magnetic field intensity. The cell compatibility of the samples is investigated using osteoblast‐like cells (MG63). Results show that the substitution of Cu2+ significantly affects the cell compatibility of the ZnMg ferrite nanoparticles. 相似文献
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Hasan Tavakoli Ashkan Khoshkharam Mohammad Baghban 《Petroleum Science and Technology》2017,35(1):92-98
Formation of gas hydrates is one of the problems in the production, processing, and transportation of natural gas. Hence, an understanding of conditions where hydrates form is necessary to overcome hydrate-related issues. The aim of this study was to develop an effective relation between the methane hydrate formation pressure based on the temperature, weight fraction of inhibitor, and molecular weight of inhibitor using the least square support vector machine. This computational model indicates the great ability of predictions for determining hydrate pressure in the presence of different inhibitors such as the methanol, ethylene glycol, diethylene glycol, and triethylene glycol. The values of R-squared (R2) and mean squared error obtained for this model are 0.9925 and 0.2325, respectively. This developed predictive tool can be applied as an accurate estimation of methane hydrate formation pressure. 相似文献
153.
This paper presents a multi-stage stochastic model for short-term transmission expansion planning considering the available transfer capability (ATC). The ATC can have a huge impact on the power market outcomes and the power system reliability. The transmission expansion planning (TEP) studies deal with many uncertainties, such as system load uncertainties that are considered in this paper. The Monte Carlo simulation method has been applied for generating different scenarios. A scenario reduction technique is used for reducing the number of scenarios. The objective is to minimize the sum of investment costs (IC) and the expected operation costs (OC). The solution technique is based on the benders decomposition algorithm. The N-1 contingency analysis is also done for the TEP problem.The proposed model is applied to the IEEE 24 bus reliability test system and the results are efficient and promising. 相似文献
154.
Ali Aboulatta Ahmed Abass Ahmed Makarem Ashkan Eliasy Dong Zhou Duo Chen Xiaoyu Liu Ahmed Elsheikh 《Journal of the Royal Society Interface》2021,18(175)
This study aims to estimate the material properties of the porcine vitreous while testing it in close to its natural physiological conditions. Eighteen porcine eyes were tested within 48 h post-mortem. A custom-built computer-controlled test rig was designed to support, load and monitor the behaviour of eye globes while being subjected to dynamic rotation cycles mimicking saccade eye movement. Specimens were glued to the base of a container, surrounded by gelatin, frozen and cut in half to expose the vitreous. After thawing, the container was subjected to concentric dynamic rotations of up to 5°, 10° or 15°, while taking 50 MP photos of the specimen every 2 ms. The images were analysed by a digital image correlation algorithm to trace the movement of marked points on the vitreous surface with different radii from the centre of the posterior chamber. The initial camera image was used in building a finite-element model of the test set-up, which was used in an inverse analysis exercise to estimate the material properties of the vitreous. Angular displacements of the monitored points were up to 3.3°, 4.1° and 3.9° in response to eye rotations of 5°, 10° and 15°, respectively. With the experimental relationships between eye rotation and angular displacements used as target behaviour, the inverse analysis exercise estimated the initial shear modulus, the long-term shear modulus and the viscoelastic decay constant of the porcine vitreous as 2.10 ± 0.15 Pa, 0.50 ± 0.04 Pa and 1.20 ± 0.09 s−1, respectively. Consideration of the viscoelasticity of the vitreous was essential to represent its experimental behaviour. Testing the vitreous in close to its normal physiological conditions produced estimations of the initial shear modulus and long-term shear modulus that were, respectively, smaller and larger than reported values (Zimberlin et al. 2010 Soft Matter 6, 3632–3635. (doi:10.1039/b925407b), Liu et al. 2013 J. Biomech. 46, 1321–7. (doi:10.1016/j.jbiomech.2013.02.006), Rossi et al. 2011 Invest. Ophthalmol. Vis. Sci. 52, 3994–4002. (doi:10.1167/iovs.10-6477)). 相似文献
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Raziyeh Reza‐Gharehbagh Ashkan Hafezalkotob Sobhan Asian Ahmad Makui Allan N. Zhang 《International Transactions in Operational Research》2020,27(5):2534-2558
While peer‐to‐peer (P2P) financing mechanisms have recently gained significant popularity, small and medium sized enterprise (SME) entrepreneurs still harbor a considerable degree of skepticism about the role of governments in promoting alternative supply chain finance (SCF) solutions in the re‐emergence of supply chain (SC) localization. This paper studies the SC financing problem of a capital‐constrained SME entrepreneur under two alternative financing schemes provided by an online P2P lending‐investment platform, namely debt financing (DF) and equity financing (EF). Considering the competition between a local and a foreign SC in a shared market, we investigate the direct (i.e., subsidizing domestic production) and indirect (i.e., subsidizing P2P platform service fee) roles of government intervention toward SC localization. Formulating a three‐level Stackelberg game model, this paper presents a scenario‐based decision‐making framework to jointly evaluate four different SCF scenarios through the lens of local SC, P2P financing platforms, and government. The results reveal that there exist three possible regions (i.e., DF, EF, and Conflict), within which the government and the P2P financing platforms can examine the alternative SCF schemes in order to achieve a mutually agreeable agreement. Our sensitivity analysis on interest rate and exchange ratio suggests that, when financed via an online P2P lending platform (i.e., DF), the local SC always achieves a higher profit under the direct intervention policy. The indirect policy, however, is preferred only when EF is the main source of SCF and the exchange ratio is sufficiently high. 相似文献
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Esmaeili Ashkan Behdin Kayhan Fakharian Mohammad Amin Marvasti Farokh 《Pattern Analysis & Applications》2020,23(3):1225-1233
Pattern Analysis and Applications - In this paper, we propose two new algorithms for transductive multi-label learning from missing data. In transductive matrix completion (MC), the challenge is... 相似文献