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New substitutional, limited solid solution of the formula Y8-yYbyV2O17 where 0 < y ≤ 2.0 was synthesized by the high-temperature reaction in the air from mixtures of α-Y8V2O17 with Yb8V2O17. The new Y8-yYbyV2O17 were characterized by powder XRD, DTA–TGA, IR, UV–vis-DRS and SEM methods. The structure, thermal stability, unit cell volume, band gap energies as well as the position of the IR absorption bands in the spectrum of Y8-yYbyV2O17 were determined. The solid solution was established to have the same structure as β-Y8V2O17 and it was found that with increasing concentration of Yb3+ ions in its crystal lattice the volume of its unit cell decreases along with its energy gap decreasing to 2.4 eV (for y = 2.0), while the IR absorption bands are shifted towards higher wavenumbers. The morphologies of the high temperature polymorph of Y8V2O17 and solid solution were analyzed. 相似文献
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Irena Roterman Katarzyna Stapor Piotr Fabian Leszek Konieczny Mateusz Banach 《International journal of molecular sciences》2021,22(7)
The water environment determines the activity of biological processes. The role of such an environment interpreted in the form of an external field expressed by the 3D Gaussian distribution in the fuzzy oil drop model directs the folding process towards the generation of a centrally located hydrophobic core with the simultaneous exposure of polar residues on the surface. In addition to proteins soluble in the water environment, there is a significant group of membrane proteins that act as receptors or channels, including ion channels in particular. The change of the polar (water) environment into a highly hydrophobic (membrane) environment is quite radical, resulting in a different hydrophobicity distribution within the membrane protein. Modification of the notation of the force field expressing the presence of the hydrophobic environment has been proposed in this work. A modified fuzzy oil drop model with its adaptation to membrane proteins was used to interpret the structure of membrane proteins–mechanosensitive channel. The modified model was also used to describe the so-called negative cases—i.e., for water-soluble proteins with a clear distribution consistent with the fuzzy oil drop model. 相似文献
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Multimedia Tools and Applications - In recent years many methods have been proposed for eye detection. In some cases however, such as driver drowsiness detection, lighting conditions are so... 相似文献
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Pawe Kowalczyk Mateusz Szymczak Magdalena Maciejewska ukasz Laskowski Magdalena Laskowska Ryszard Ostaszewski Grzegorz Skiba Ida Franiak-Pietryga 《International journal of molecular sciences》2021,22(2)
Silver and its nanoparticles (AgNPs) have different faces, providing different applications. In recent years, the number of positive nanosilver applications has increased substantially. It has been proven that AgNPs inhibit the growth and survival of bacteria, including human and animal pathogens, as well as fungi, protozoa and arthropods. Silver nanoparticles are known from their antiviral and anti-cancer properties; however, they are also very popular in medical and pharmaceutical nanoengineering as carriers for precise delivery of therapeutic compounds, in the diagnostics of different diseases and in optics and chemistry, where they act as sensors, conductors and substrates for various syntheses. The activity of AgNPs has not been fully discovered; therefore, we need interdisciplinary research to fulfil this knowledge. New forms of products with silver will certainly find application in the future treatment of many complicated and difficult to treat diseases. There is still a lack of appropriate and precise legal condition regarding the circulation of nanomaterials and the rules governing their safety use. The relatively low toxicity, relative biocompatibility and selectivity of nanoparticle interaction combined with the unusual biological properties allow their use in animal production as well as in bioengineering and medicine. Despite a quite big knowledge on this topic, there is still a need to organize the data on AgNPs in relation to specific microorganisms such as bacteria, viruses or fungi. We decided to put this knowledge together and try to show positive and negative effects on prokaryotic and eukaryotic cells. 相似文献
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Damian Przestacki Mateusz Kukliński Aneta Bartkowska 《The International Journal of Advanced Manufacturing Technology》2017,93(9-12):3111-3123
In this study, a nickel-based superalloy, Waspaloy, was laser heat treated with diode laser. Single laser tracks were manufactured with different laser beam power densities between 63 and 331 kW/cm2, and scanning laser beam speed ranged from 5 to 100 m/min. It was found that laser heat treatment of Waspaloy causes decrease in material hardness—the microhardness in laser tracks is about 300 HV0,1 while the microhardness of substrate is ranged from 300 to 600 HV0,1—which is a positive phenomenon for laser-assisted machining of investigated material. Impacts of laser heat treatment parameters on laser tracks properties were identified for obtaining multiple laser tracks with the most homogenous thickness. Moreover, roughness of heated layers was measured to specify surface quality after laser heat treatment. Multiple laser tracks were produced using different scanning laser beam speed and distances between laser tracks ranged from 0.125 to 1 mm. It was found that if scanning laser beam speed is 75 m/min and distance between laser tracks is equal to or lower than 0.25 mm, in microstructures of multiple laser tracks, cracks are occurring. The most suitable laser heat parameters for obtaining heated layers, and which can be used for laser-assisted machining, were identified as laser beam power density 178.3 kW/cm2, scanning laser beam speed 5 m/min, and distance between laser tracks 0.125 mm. 相似文献
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The sorption behavior of Sc(III) on different materials including activated carbon (AC), carbon nanotubes (CNTs), graphene oxide (GO), and the chelating resin Chelex 100 was investigated. In general, the sorption of scandium increases with increasing pH. For pH in the range from 2.5 to 5.5, the sorption of Sc(III) onto CNTs, GO, and Chelex 100 is quantitative, whereas a significantly lower amount of scandium ions was retained on AC. The specific amount of Sc(III) adsorbed at pH 2 attained 2.1, 2.9, 36.5, and 37.9 mg g?1 for AC-COOH, Chelex 100, GO, and CNTs-COOH, respectively. At pH 4, a similar value was obtained for oxidized AC (2.2 mg g?1), whereas the specific amount adsorbed significantly increased for Chelex (23.4 mg g?1). The highest values were obtained for GO (39.7 mg g?1) and oxidized CNTs (42.5 mg g?1). Better kinetic retention was observed at pH 2 for CNTs and GO, whereas at pH 4 the kinetic behavior of Chelex 100, GO, and CNTs toward Sc(III) was comparable. 相似文献