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121.
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It would be helpful to achieve appropriate synthetic routes to attain larger-scale production at industrial levels of nanocomposites at low costs. In the present work, diphasic composites with core–shell nanostructures formed by La2Fe2O6/CoFe2O4 are investigated. The core–shell structure is fabricated via different preparation methods. The advantages and the demerits of the synthesis techniques are discussed. The presence of both the spinel CoFe2O4 nano ferrite and orthorhombic La2Fe2O6 perovskite phases is revealed by X-ray diffraction. XPS spectroscopy is utilized to investigate the chemical composition of the prepared samples. The hysteresis loops of the prepared samples exhibit a smooth loop that is resulted from the existence of two homogeneous magnetic phases. For the first time, it has been found that the preparation conditions have the advantage of reducing the switching field distribution value for the core–shell nanoparticles. Exchange coupled core–shell nanoparticles present a high potential to regulate the magnetic properties for numerous applications such as heavy metal removal and/or data storage devices. The maximum adsorption capacity (qm) of Cr III on the core–shell (S3) is higher compared to other adsorbents previously testified in the literature. The cost-effective and eco-friendly prepared core–shell samples with good metal removal capacity have great potential for commercialization.

  相似文献   
123.
Managerial flexibility in infrastructure investment and replacement decisions adds value. Real options analysis (ROA) captures this value under uncertain market prices. The concept of ROA is that future unfavourable payoffs can be deferred as soon as more information about market prices becomes available. The popularity of ROA is seen in a growing number of case studies on real assets. Despite its increasing popularity, ROA has not gained a foothold in public infrastructure decision making. One of the difficulties in the application of ROA is the required estimation of market variables. To avoid this, a simplified but not correct version of ROA is easily applied, referred to as a Decision Tree Approach (DTA) to ROA. Another difficulty is that infrastructure assets are subject to other types of uncertainties, defined here as asset uncertainties. This study investigates the value of managerial flexibility in a public infrastructure replacement decision. The uncertainty drivers are the strength of a bridge, political decisions regarding traffic flow and the price development of construction costs. Three valuation approaches are compared: DTA, ROA and the DT approach to ROA. Although it is complex, ROA certainly adds value in public infrastructure decision making when market price uncertainty is prevalent. However, in the absence of reasonable estimates of market variables, the DT approach to ROA is the best alternative. In the absence of market price uncertainties, ROA should be avoided DTA is to be preferred.  相似文献   
124.
In the aerodynamic industry, one of the major problems of interest is the lift enhancement without any increase in the drag. In this paper, an attempt is made to increase the lift coefficient by delayed boundary layer separation using suction at various points, also the study is carried out to identify the optimum location for suction which provides maximum lift augmentation. The experiment is conducted with selected suction pressures of 60, 70, 80, 90?kN/m2 at different locations in the range of 40–75% of the chord length of the airfoil. Among the selected pressures, the lowest one at the 70% length provides maximum performance. The critical Reynolds number occurs at around 95% of the length instead of 45% of the length when the same experiment is conducted without suction. The suction also assists in the heat transfer enhancement over the airfoil surface.  相似文献   
125.
Protection of Metals and Physical Chemistry of Surfaces - The methods of describing absolute adsorption isotherms of binary nonelectrolyte solutions components on macro- and microporous adsorbents...  相似文献   
126.
Protection of Metals and Physical Chemistry of Surfaces - The results of studying the equilibrium and kinetics of Cu2+ ions’ sorption from aqueous solutions by the initial and modified wool...  相似文献   
127.
Protection of Metals and Physical Chemistry of Surfaces - Protective properties of polymer coatings are mainly determined by their adhesion properties. Organosilanes represent the most commonly...  相似文献   
128.
Protection of Metals and Physical Chemistry of Surfaces - In this work, preparation of thermal barrier coatings based on zirconium oxide is shown. The phased treatment of the copper substrate is...  相似文献   
129.
孙元  唐建 《城市建筑》2014,(4):237-237
针对城市慢行交通系统的导视进行了研究,提出了基于包容性理念的综合导视系统的设计概念,设计过程包括了原型测试、行人动线研究、互动导视系统的设计等内容。  相似文献   
130.
唐德浩 《城市建筑》2014,(18):383-383
建设项目管理信息系统是处理工程管理信息的人机系统。它通过收集、存储及分析工程项目实施过程中的有关数据,辅助工程项目的管理人员和决策者规划、决策和检查,其核心是辅助对工程项目目标的控制。  相似文献   
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