High-strain-rate superplasticity of nanocrystalline aluminum alloy 1570

The structure and mechanical properties of nanocrystalline aluminum alloy 1570 obtained by means of severe plastic deformation have been studied. Being tested in a temperature range from 300 to 400°C, the alloy exhibits high-strain-rate superplasticity. At 400°C, the superplasticity is manifested in a very broad range of strain rates, extending from 5 × 10^?3 to 1 s^?1.     

Furfural Oxidation with Hydrogen Peroxide Over ZSM-5 Based Micro-Mesoporous Aluminosilicates

Micro-mesoporous aluminosilicates based on ZSM-5 zeolite, obtained by a dual template method, as well as in the presence of a dual-functional template (i.e. a Gemini-type surfactant), were tested in the oxidation of furfural with hydrogen peroxide. Even substantial changes in acidity and porosity of the catalysts result in minor variations of selectivity towards the desired products. Application of the synthesized zeolite-based materials in the oxidation of furfural with hydrogen peroxide leads to formation of 2(5H)-furanone (yield up to 28.5%) and succinic acid (up to 19.5%) as the main C4 reaction products. The kinetic model developed previously to treat the results for oxidation of furfural over sulfated zirconia was able to describe the data also for micro-mesoporous aluminosilicates.

Graphical Abstract

     

Building 2D quasicrystals from 5-fold symmetric corannulene molecules

Nano Research - The formation of long-range ordered aperiodic molecular films on quasicrystalline substrates is a new challenge that provides an opportunity for further surface functionalization....     

Detection of bubbles as concentric circular arrangements

The paper proposes a method for the detection of bubble-like transparent objects in a liquid. The detection problem is non-trivial since bubble appearance varies considerably due to different lighting conditions causing contrast reversal and multiple interreflections. We formulate the problem as the detection of concentric circular arrangements (CCA). The CCAs are recovered in a hypothesize-optimize-verify framework. The hypothesis generation is based on sampling from the partially linked components of the non-maximum suppressed responses of oriented ridge filters, and is followed by the CCA parameter estimation. Parameter optimization is carried out by minimizing a novel cost-function. The performance was tested on gas dispersion images of pulp suspension and oil dispersion images. The mean error of gas/oil volume estimation was used as a performance criterion due to the fact that the main goal of the applications driving the research was the bubble volume estimation. The method achieved 28 and 13 % of gas and oil volume estimation errors correspondingly outperforming the OpenCV Circular Hough Transform in both cases and the WaldBoost detector in gas volume estimation.     

Size and shape influence of luminescent orthovanadate nanoparticles on their accumulation in nuclear compartments of rat hepatocytes

In this paper the process of nonfunctionalized negatively charged orthovanadate nanoparticle accumulation and redistribution in cells dependent on their shape and size was investigated. Aqueous colloidal solutions of nReVO₄:Eu^3 + (Re = Gd, Y, La) luminescent nanocrystals of different sizes and shapes have been synthesized. The average sizes of spherical particles were 2, 20, and 300 nm, of spindle-like particles – 22 × 6.3 nm, and of rod-like particles – 57 × 4.4 nm. Luminescence of nReVO₄:Eu^3 + nanocrystals was effectively excited by UV and visible irradiation. By means of luminescence microscopy and luminescence microspectroscopy, it has been revealed that spherical nanocrystals with an average diameter of 2 nm tend to accumulate mainly in the rat hepatocyte nuclei in situ and also in the isolated nuclei of these cells. An additional experiment has shown that nanoparticles reveal tropism to nuclear structural components. The penetration into nuclei does not require any modifications of the surface of nanoparticle and is governed by the shape and size of nanoparticle and also is determined by the cellular type.     

West Siberian palsa peatlands: distribution,typology, cyclic development,present day climate-driven changes,seasonal hydrology and impact on CO2 cycle

Palsa peatlands occupy extensive areas in Western Siberia which is one of the most paludified flat lowlands of the world. Climatic changes in Western Siberia are more dramatic compared with other northern regions, and changes in palsa landscapes are more notable due to the severe continental climate here. The distribution, peculiarities and climate-indication capacities of West Siberian palsas are poorly known outside Russia. Thus, Western Siberia is one of the most interesting vast natural polygons for studying climate-driven changes in the landscapes. This paper aims to fill the gap in knowledge on West Siberian palsas and their capacity as a climate regulator. We present issues in distribution, typology and cyclic development of palsa peatlands and their actual climate-driven changes. We also analyse the role of palsas in the atmospheric cycle of CO₂, and the hydrology of the palsa regions.     

The capability to reduce primary energy demand in EU housing

The European Union has been demonstrating its adherence to energy efficiency policy in the last decade. At the main EU summits there were stated the requirements to reduce energy consumption in the EU, and to make it sustainable over the long term. The “20-20-20” promise of a 20% share of renewable energies in total EU energy consumption and a 20% reduction of greenhouse gas emissions in the EU by 2020 was determined in 2007 and affirmed in 2008. The paper deals with the evaluation of some ways of reaching a 20% reduction in primary energy demand in housing. For that purpose some measures leading to such a reduction for a dwelling house are estimated. These measures require an additional investment into the energy performance of a building. For the achievement of goals stated by the European Parliament in energy demand it will be necessary to involve a considerable level of financial and technical support in these spheres. An estimation of the amount of supporting program funds is also presented in the paper.