In this work, the joint photocatalytical and bactericidal potential, under UV radiation, of titania and silver nano powders dispersed in PMMA and deposited on porous ceramic substrates (40 and 80 ppi) by dip- and spra...
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In this work, the joint photocatalytical and bactericidal potential, under UV radiation, of titania and silver nano powders dispersed in PMMA and deposited on porous ceramic substrates (40 and 80 ppi) by dip- and spray-coating, were investigated in low power consumption water purification reactors, using the Escherichia coli (E. coli) as reference pathogen. The results show the effect of different reactor morphologies (porosity, permeability, mechanical strength) on the bactericidal efficiency.
In a pressure-temperature (P−T) diagram for synthesizing IrTe2 compounds, the well-studied trigonal (H) phase with the CdI2-type structure is stable at low pressures. The superconducting cubic (C) phase can be synthes...
In a pressure-temperature (P−T) diagram for synthesizing IrTe2 compounds, the well-studied trigonal (H) phase with the CdI2-type structure is stable at low pressures. The superconducting cubic (C) phase can be synthesized under higher temperatures and pressures. A rhombohedral phase with the crystal structure similar to the C phase can be made at ambient pressure; but the phase contains a high concentration of Ir deficiency. In this paper we report that a rarely studied monoclinic (M) phase can be stabilized in narrow ranges of pressure and temperature in this P−T diagram. The peculiar crystal structure of the M−IrTe2 eliminates the tendency to form Ir-Ir dimers found in the H phase. The M phase has been fully characterized by structural determination and measurements of electrical resistivity, thermoelectric power, DC magnetization, and specific heat. These physical properties have been compared with those in the H and C phases of Ir1−xTe2. Moreover, magnetic and transport properties and specific heat of the M−IrTe2 can be fully justified by calculations with the density-functional theory presented in this paper.
The entropic effects in the comicellization behavior of amphiphilic AB copolymers differing in the chain size of solvophilic A parts were studied by means of molecular dynamics simulations. In particular, mixtures of ...
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The entropic effects in the comicellization behavior of amphiphilic AB copolymers differing in the chain size of solvophilic A parts were studied by means of molecular dynamics simulations. In particular, mixtures of miktoarm star copolymers differing in the molecular weight of solvophilic arms were investigated. We found that the critical micelle concentration values show a positive deviation from the analytical predictions of the molecular theory of comicellization for chemically identical copolymers. This can be attributed to the effective interactions between copolymers originated from the arm size asymmetry. The effective interactions induce a very small decrease in the aggregation number of preferential micelles triggering the nonrandom mixing between the solvophilic moieties in the corona. Additionally, in order to specify how the chain architecture affects the size distribution and the shape of mixed micelles we studied star-shaped, H-shaped, and homo-linked-rings–linear mixtures. In the first case the individual constituents form micelles with preferential and wide aggregation numbers and in the latter case the individual constituents form wormlike and spherical micelles.
Equal-channel angular pressing （ECAP） is a prominent technique that imposes severe plastic deformation into materials to en- hance their mechanical properties. In this research, experimental and numerical approaches...
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Equal-channel angular pressing （ECAP） is a prominent technique that imposes severe plastic deformation into materials to en- hance their mechanical properties. In this research, experimental and numerical approaches were utilized to investigate the mechanical prop- erties, strain behavior, and damage prediction of ECAPed 7025 aluminum alloy in various conditions, such as die channel angle, outer comer angle, and friction coefficient. Experimental results indicate that, after the first pass, the yield strength, ultimate tensile strength, and hardness magnitude are improved by approximately 95%, 28%, and 48.5%, respectively, compared with the annealed state, mainly due to grain re- finement during the deformation. Finite element analysis shows that the influence of die channel angle is more important than that of outer comer angle or friction coefficient on both the strain behavior and the damage prediction. Also, surface cracks are the main cause of damage during the ECAP process for every die channel angle except for 90°; however, the cracks initiated from the neighborhood of the central re- gions are the possible cause of damage in the ECAPed sample with the die channel angle of 90°.
It is predicted that wearable technology will result in a revolution in the world. However, the advancement has been limited by a critical challenge, i.e., the conventional power systems can not satisfy the requiremen...
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It is predicted that wearable technology will result in a revolution in the world. However, the advancement has been limited by a critical challenge, i.e., the conventional power systems can not satisfy the requirements of lightweight, miniature and integratable in wearable electronics. We have developed a new family of fiber-shaped energy devices including solar cells, electrochemical capacitors and lithium-ion batteries that share many advantages including lightweight, thin and integratable compared with their traditioinal planar counterparts.
Biointerface design that targets osteogenesis is a growing area of research with significant implications in biomedicine. materials known to either support or stimulate osteogenesis are composed of a biomimetic cerami...
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Biointerface design that targets osteogenesis is a growing area of research with significant implications in biomedicine. materials known to either support or stimulate osteogenesis are composed of a biomimetic ceramic material, such as bioactive glass. Bioactive glass is osteoproductive, and the potential for osteoproductivity can be enhanced by the addition of proteins or other additives designed to alter functionality. In addition, soluble growth factors are often added to osteogenic culture on bioactive glasses, further intensifying the effects of the material. In this paper, synthetic peptide combinations, covalently bound to a three-dimensional bioactive glass network, are used to mimic the effects of the whole fibronectin and bone morphogenetic proteins (BMP) 2 and 9. Peptide-silanes possessing critical binding sequences from each of these proteins are synthesized and used to decorate the surface of three-dimensional (3D) nano-macroporous bioactive glass. MC3T3 preosteoblast cells are then assessed for differentiation on the materials in the absence of soluble differentiation cues. MC3T3 preosteoblasts undergo enhanced differentiation on the peptide-silane samples over the standard nano-macroporous bioactive glass, and the differentiation capacity of the cells exposes only to peptide-silane surfaces approaches that of cells grown in chemical differentiation induction media.
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