The properties of samarium doped ceria oxide thin films grown by e-beam deposition technique

One of the main challenges in today's solid oxide fuel cell (SOFC) technology is the reduction of their operating temperature. New types of oxygen ion conducting materials are currently under investigation to overcome the problems which SOFC faces at high temperatures. Samarium doped ceria oxide (SDC) was the material of investigation in this work. Optical quartz (SiO₂) and Fe–Ni–Cr alloy (Alloy 600) were the two types of chosen substrates onto which SDC thin films were deposited by e-beam evaporation technique. The bias voltage was applied to the substrate during film growth. It had an influence on film formation, its microstructure and density because of the ionized particles presence in the SDC vapor stream. Changes in crystallite size and surface morphology were determined from X-ray diffraction data and scanning electron microscopy images. Influence of bias voltage on porosity of formed SDC thin films on optical quartz were calculated from transmittance spectra data by using Swanepoel method. The porosity decreases up to 12% by decreasing bias voltage from 0 to ?150 V.     

Use of Cullet of Different Chemical Compositions in Foam Glass Production

The results of studying the possibility of using cullet of different chemical compositions accumulated at dumping grounds for foam glass production are described. It is established that sodium silicate introduced into cullet in the form of water glass partly destroys milled cullet and homogenizes the chemical composition of the batch and its most significant technological properties. Due to the chemical reaction between water glass and the surface of milled cullet particles, silicates are formed containing bound water, which is released at high temperatures (600 – 620°C) and facilitates frothing of foam glass. Water glass in a batch increases the quantity of the vitreous phase and decreases the propensity of glass for crystallization.     

Mesenchymal and Proneural Subtypes of Glioblastoma Disclose Branching Based on GSC Associated Signature

Glioblastomas (GBM)—the most common, therapy-resistant, and lethal tumors driven by populations of glioma stem cells (GSCs) are still on the list of the most complicated pathologies. Thus, deeper understanding and characterization of GSCs is indispensable to find suitable targets and develop more effective therapies. In the present study, we applied native glioblastoma cells and GSCs sequencing, screened for GSC-specific targets and checked if the signature is related to GBM patient pathological, clinical data as well as molecular subtypes applying TCGA cohort. Data analysis revealed that tumors of proneural and mesenchymal subtypes are branching in separate clusters based on screened gene expression. Samples of the same subtype revealed significantly different patient survival prognosis as well as recurrence chance between the clusters. Recently, different subpopulations of mesenchymal GSC demonstrating different properties were shown, which indicates possible internal heterogeneity of GBM subtypes as well. Current findings also revealed branching of molecular GBM subtypes that were significantly linked to patient outcome and that might be decided by distinct GSC subpopulations.     

The peculiarities of sprayed liquid’s thermal state change,as droplets are heated by conduction

The change of thermal state and phase transformation intensity of sprayed water, n-hexane, n-heptane and n-decane is numerically modelled in the case, as droplets are heated by conduction; the influence of the Knudsen layer is neglected; warming and evaporation of the droplets has no influence on the state of the carrying air flow. The research results prove that a peculiar change of the thermal state of sprayed liquid, irrespective of droplet’s dispersivity, exists in the time scale, expressed by Fourier number. The above-mentioned change can be conveniently defined by the characteristic curves, representing the change of a droplet surface, centre, and mean mass temperatures, which are sensibly influenced by temperature of gas mixture and partial pressure of liquid vapour in it. As these characteristic curves were expressed in regards to the initial and equilibrium evaporation temperatures of liquid, the universal curves, representing the change of thermal states of the examined liquids, were obtained in the time scale, expressed by Fourier number. It is shown that liquid evaporation rate and the change of a droplet dimension can also be described by characteristic curves.     

Influence of fibrous additives on properties of aerated autoclaved concrete forming mixtures and strength characteristics of products

The influence of fibrous additives of non-hydrophilized and hydrophilized carbon, polypropene, basalt and kaoline fibre on properties of aerated autoclaved concrete (AAC) forming mixture, as well as on properties of final product was investigated.All these fibrous additives, both non-hydrophilized and hydrophilized, have effect on fluidity and swelling of forming mixtures and increase plastic strength. Along with growing content of each fibrous additive within limits from 0.1% to 0.4% of mass of solid components, the fluidity and swelling of forming mixtures decreases, while the plastic strength increases.All investigated fibrous additives, both hydrophilized and non-hydrophilized, increase the compression- and flexural strengths of AAC. The optimal content of all fibrous additives to be added for obtaining of greatest compression- and flexural strengths is 0.3% counting of dry material in the forming mixture. By capacity to increase the compression- and binding strengths, the fibrous additives may be lined up in the following order: carbon fibre > polypropene fibre > basalt fibre > kaoline fibre. All fibrous additives increase flexural strength more than that of compression. Hydrophilized fibres increase compression- and flexural strengths of concrete more than the respective non-hydrophilized ones.Basing on the results of investigations performed as to fibre-reinforced AAC structure by scanning electron microscope, as well as on the results of earlier performed investigations with fibres used for reinforcement to find out their chemical resistance to treatment of them in the autoclave by alkaline solutions, the pH value of which corresponds to that of hardening alkaline binding medium of concretes, the influence of properties of fibrous additives on efficiency of reinforcement was explained.     

Obtaining of high surface roughness copper deposits by electroless plating technique

The use of pyridine-2,6-dicarboxylic and 4-hydroxypyridine-2,6-dicarboxylic acids as copper(II) ligands in formaldehyde-containing alkaline electroless copper plating solutions allowed to obtain copper layers with extremely high surface roughness factor reaching approximately 120. The Cu deposits of higher surface area were formed at highly negative open-circuit (mixed) potentials; the correlation between copper electrode overpotential and roughness of the deposit was found and discussed. The copper films obtained demonstrate a high electrocatalytic activity in anodic formaldehyde oxidation process, the oxidation rate reaches 40 mA cm⁻² and exceeds considerably that for other copper surfaces.     

Covert visual search: A comparison of performance by humans and macaques (Macaca mulatta).

The duration of the visual search by human participants for visual features is independent of the number of targets being viewed. In contrast, search for targets formed by conjunction of features is characterized by reaction times (RTs) that increase as a linear function of the number of items viewed, suggesting that the target detection requires scrutiny of the search array by focal attention. Macaque (Macaca mulatta) and human performance on feature and conjunction search tasks was compared in 7 human Ss and 5 female monkeys by using color or motion, or by conjunctions of color and motion. Like human participants, monkeys exhibited a dichotomy between feature and conjunction search performance. This finding suggests that humans and macaques engage similar brain mechanisms for representation of feature and conjunction targets. This behavioral paradigm can thus be used in neurophysiological experiments directed at the mechanisms of feature integration and target selection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)