El origen del endurecimiento de metales y aleaciones nanoestructurados

14 pages, 8 figures.[EN] Nanostructured metals and alloys have a variety of chemical and physical properties that are greatly modified by the nano-scale of their microstructure. At the same time, these materials generally show very high strength, although ductility or toughness may not be good. Strength increases as the microstructure scale reduces from the macro-micro level and even finer, but sometimes the strength appears to fall as the structure scale approaches the nano level. These strength variations are examined here, and the mechanisms responsible for both strengthening and weakening are discussed. The fall in ductility and toughness as materials become nanostructured is a complex topic that requires extensive analysis, but this will not be treated in the present overview.[ES] Los metales y aleaciones nanoestructuradas muestran una serie de propiedades químicas y físicas fuertemente modificadas cuando su microestructura entra en la escala nano. A la vez, estos materiales muestran generalmente alta resistencia pero mediocre ductilidad o tenacidad. La resistencia aumenta cuando baja la escala de la microestructura desde el nivel micro hacia el nivel nano, pero a veces la resistencia parece reducir por las microestructuras mas finas. Se examinan aquí todas estas variaciones y se discuten los mecanismos responsables del endurecimiento y ablandamiento. Los cambios de ductilidad o tenacidad cuando la microestructura entra en la escala nano necesitan un análisis detallado que no se trata en este articulo.Peer reviewe

Ileocecal Intussusception with Histomorphological Features of Inflammatory Neuropathy in Adenovirus Infection

The pathophysiological mechanisms for ileocecal intussusception in children with adenovirus infection are not well characterized. Here we demonstrate coincidence of adenovirus infection and inflammatory neuropathy of myenteric plexus in two children with ileocecal intussusception. Inflammatory neuropathy, an unspecific morphological feature which is found in peristalsis disorders, was morphologically characterized by the influx of CD3 positive lymphocytes in nervous plexus. To our knowledge, this is the first report suggesting peristalsis disorders from inflammatory neuropathy as additional mechanism in the pathophysiological concept of adenovirus-associated ileocecal intussusception

Adsorption of Hydrocarbons Using Natural Adsorbents of Plant Origin

The paper investigates adsorption activity of natural sorbents to be used to clean up water surface from hydrocarbons under various temperatures. The natural adsorbents were compared by their oil capacity, buoyancy, and water absorption. It was revealed that Nature sorb (Canada) and Sphagnum Dill (Russia) natural sorbents demonstrate good buoyancy (up to 700 hours) and great oil capacity, and better sorption properties in comparison with the sawdust. The natural sorbents introduced can increase the efficiency of water surface cleaning-up until the water is almost clean and the residual oil content in water is less than 0.03 g/l

Безотходное использование углей

В работе сравниваются расчетная и аналитическая зольность отходов углеобогащения. Рассматриваются возможные пути и необходимость в сокращении отходов использования угля. Предложена модель безотходного использования углей.In this work the calculated and analytical ash contents of coal enrichment waste are compared. Possible ways and necessity in reducing coal waste are studied. The model for the non-waste use of coals is proposed

Development of virtual polygon in Unity3D

The paper is devoted to research and designing of autonomous car - a self-governing car in which artificial intelligence will take the role of driver. In today's world, the present invention is necessary because today humanity cannot imagine being without any types of transport

Эколого-технологические основы формирования визуальной среды города (на примере многофункционального здания г. Томска)

Процессы урбанизации, которые особо ускорились в ХХ веке, вызывают большой интерес у представителей различных наук и у самих горожан, поскольку бурный рост городского населения превращается в глобальную проблему и сильно меняет городскую среду. В ходе роста и развития городов концептуально иной становится окружающая человека среда с новым пониманием ценностей жизни, красоты и гармонии. Как показывает действительность и многочисленные исследования - естественная связь человека с природой значительно ослабевает именно в городах. Это в значительной мере оказывает влияние на психоэмоциональное и физическое состояние горожан. Изучая визуальную среду современного города, мы можем существенным образом обогатить эстетическую составляющую и несколько смягчить негативные последствия урбанизации.The rapid growth of the urban population presents a global challenge and ultimately augments the urban environment. While cities growth and develop, the environment with new understandings of values, beauty and harmony becomes conceptually different. In most cities, the natural connection of individuals with nature has significantly weakened. Their everyday environment is an artificial urban environment. In cities a special lifestyle different from the style of life in the countryside is formed, affecting to a large extent the physical and especially the mental health of the citizens. Through exploring the visual environment of the modern city, we can significantly enrich the aesthetic component and mitigate the negative effects of anthropogenic impact, creating a favorable habitat

Directional wavelet based features for colonic polyp classification

In this work, various wavelet based methods like the discrete wavelet transform, the dual-tree complex wavelet transform, the Gabor wavelet transform, curvelets, contourlets and shearlets are applied for the automated classification of colonic polyps. The methods are tested on 8 HD-endoscopic image databases, where each database is acquired using different imaging modalities (Pentax's i-Scan technology combined with or without staining the mucosa), 2 NBI high-magnification databases and one database with chromoscopy high-magnification images. To evaluate the suitability of the wavelet based methods with respect to the classification of colonic polyps, the classification performances of 3 wavelet transforms and the more recent curvelets, contourlets and shearlets are compared using a common framework. Wavelet transforms were already often and successfully applied to the classification of colonic polyps, whereas curvelets, contourlets and shearlets have not been used for this purpose so far. We apply different feature extraction techniques to extract the information of the subbands of the wavelet based methods. Most of the in total 25 approaches were already published in different texture classification contexts. Thus, the aim is also to assess and compare their classification performance using a common framework. Three of the 25 approaches are novel. These three approaches extract Weibull features from the subbands of curvelets, contourlets and shearlets. Additionally, 5 state-of-the-art non wavelet based methods are applied to our databases so that we can compare their results with those of the wavelet based methods. It turned out that extracting Weibull distribution parameters from the subband coefficients generally leads to high classification results, especially for the dual-tree complex wavelet transform, the Gabor wavelet transform and the Shearlet transform. These three wavelet based transforms in combination with Weibull features even outperform the state-of-the-art methods on most of the databases. We will also show that the Weibull distribution is better suited to model the subband coefficient distribution than other commonly used probability distributions like the Gaussian distribution and the generalized Gaussian distribution. So this work gives a reasonable summary of wavelet based methods for colonic polyp classification and the huge amount of endoscopic polyp databases used for our experiments assures a high significance of the achieved results.(VLID)223912