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81.
S. M. Reshetnikov F. Z. Gil’mutdinov E. M. Borisova O. R. Bakieva 《Protection of Metals and Physical Chemistry of Surfaces》2016,52(7):1121-1127
Using the method of recording anode potentiodynamic curves in neutral and mildly alkaline borate buffer solutions, the corrosion and electrochemical behavior of iron-armco samples bombarded with oxygen ions is studied. It is shown by the method of X-ray photoelectron spectroscopy that, during such bombardment, implantation of oxygen into the surface layers of iron occurs. Therein, iron oxides of variable composition and various forms of adsorbed and absorbed oxygen are formed. These oxygen formations contribute to transfer of the iron surface to a more corrosion-resistant, passive state. 相似文献
82.
Miguel Manzano Antonio J. Salinas Francisco J. Gil María Vallet-Regí 《Journal of materials science. Materials in medicine》2009,20(9):1795-1801
In this paper, different organic–inorganic hybrid materials based in the CaO–SiO2–poly(dimethyl siloxane) PDMS system have been characterised by means of nanoindentation and their static mechanical properties
(Young’s modulus, and hardness) have been investigated. These mechanical properties have been discussed in relation to the
chemical composition and structure of the different hybrid materials. Besides, the mechanical behaviour of hybrid materials
is visco-elastic and it therefore presents phenomena of creep that will be influenced by the temperature of the mechanical
test; undoubtedly, a temperature of 37°C accelerates the processes of creep. 相似文献
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Due to the increase in the number and popularity of applications such as e-commerce or on-line booking systems, typical of the Web 2.0, dynamic contents are becoming more and more frequent. This trend suggests the review of widely accepted paradigms and models for the World Wide Web. As a system that is continuously changing, both in the offered applications and in its infrastructure, performance evaluation studies are a main concern to provide sound proposals when designing new web-related systems. Although the dynamism in the workload characterization has also been tackled in previous research, it has not been modeled in a precise way yet because of its complex nature.In this paper we propose the Dweb model which represents the dynamism of current web applications in the workload characterization. Dweb is based on three main concepts that allow to model dynamic workload: navigation, workload test and workload distribution. In addition, a dynamic workload generator has been implemented to show the practical application of the proposed model, which has been illustrated through a case study. 相似文献
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M. Gil S. Estévez N. Kontoudakis F. Fort J. M. Canals F. Zamora 《European Food Research and Technology》2013,237(4):481-488
Two red wines with a very high ethanol content were partially dealcoholized by reverse osmosis, so that the influence of this technique on wine color, chemical composition and sensory quality could be studied. No statistically significant differences were found in pH, color intensity, total phenolic index, proanthocyanidin concentration and their mean degree of polymerization between control wines and partially dealcoholized wines (?1 and ?2 vol. %). Some slight but significant differences were found in titratable acidity, anthocyanins, CIELab coordinates and polysaccharides. However, these differences were really quite small and only significant in a few cases. Moreover, a trained panel of tasters had severe difficulty in distinguishing between control and partially dealcoholized wines in triangular tests, and results were statistically significant only in some of the comparisons. It is concluded that this technique can be very useful for the partial dealcoholization of red wines because they hardly alter their composition and sensory characteristics. 相似文献