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By studying the physical properties of oilseed rape, the obtained data have a practical application when constructing machines for sowing, harvesting, transporting, warehouse design, and seed processing. During oilseed rape harvest, seed moisture can be different, and it is imperative to understand the physical properties of the seeds to correctly adjust the equipment. Depending on the climate conditions, oilseed rape can have different seed moisture content. This investigation included three winter varieties of oilseed rape widely grown in European countries. The effect of different degrees of seed moisture (6, 11, 16, and 21%) on the physical properties of oilseed rape, seeds were investigated by using standard methods in three growing seasons (2015/17). When moisture content in the kernels increased, 1000-grain weight, seed volume and porosity, static and dynamic angles of repose also increased in the tested varieties. Increased seed moisture reduced the true density and bulk density of the three tested varieties. The highest coefficient of friction was found on plywood and the lowest on stainless steel sheet. Oil and protein contents of the tested varieties ranged between 39.38 and 43.90%, and 17.65 and 23.12%, respectively. Oleic, linoleic, α-linolenic, and palmitic acids were the most representative fatty acids. Knowing the physical and chemical properties of oilseed rape seeds, it would be possible to significantly contribute to the breeding process in order to identify highquality genotypes. [ABSTRACT FROM AUTHOR]

Aim: The purpose was to assess ergonomic risk level in dentistry, which may contribute to manifestation of musculoskeletal disorders (MSD).

Essential oils are widely used in medicine, dentistry and cosmetology as flavour and odour corrigents in various substances for oral hygiene. The aim of this study was to present comprehensively the possibilities for application of Melaleuca Alternifolia essential oil in dentistry based on the analysis of contemporary scientific and professional publications. The application of Tea tree essential oil in the treatment of periodontal, fungal and viral diseases is very efficient. The study of antimicrobial potential of ten different essential oils confirmed the efficiency of Tea tree oil against numerous Gram+ and Gram- bacteria. In vitro studies of bacteriostatic, bactericidal and fungicidal effect of Tea tree oil solution against ten different microorganisms confirmed sensitivity of the following microorganisms: Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum and Porphyromonas gingivalis, and slightly weaker effect against Streptococcus Mutans and Prevotella intermedia. Tea tree is very effective in the treatment of various diseases and is an introduction and momentum for the application of plant substances in the treatment of numerous diseases in dentistry. .

A nanocomposite consisting of lead sulfide (PbS) nanoparticles (NPs) with average diameter of 26 Ǻ, according to absorption threshold shift, and polyvinyl alcohol (PVA) was characterized using far-infrared absorption spectroscopy. The experimental results are consistent with theoretical calculations that include proper mechanical boundary conditions at the nanocrystal-host interface.

Mount Tara is among the most important centers of Balkan and European ecosystem and species biodiversity. It is characterized by diversified and well-maintained communities of old deciduous and mixed coniferous forests (beech/fir/spruce). They represent a unique example of well preserved forests in SE Europe with numerous endemic and relict species of indigenous flora and fauna. The geographical information system (GIS) that we have created has proved an excellent tool for valorization and protection of all natural values and potentials of Tara National Park.

A catalytic coating, composed of a mixture of nanocrystals of Pt and RuO2, used for oxidation of CH3OH, was formed by the thermal procedure. The size of the RuO2 nanocrystals was increasing and of Pt was decreasing with increasing the content of RuO2. The optimal coating composition depended on potential. At more positive potentials, the optimal coatings contained lower amounts of RuO2. The oxidation reaction of CH3OH on the coatings with the RuO2 content higher than optimal, was determined by dehydrogenization of CH3OH. At lower amounts of RuO2, oxidation of CH3OH was determined by the oxidation reaction of intermediates COad with oxy species of ruthenium. The catalytic effect was caused by a bifunctional mechanism. The bifunctional mechanism is based on the fact that oxy species were formed on Ru at more negative potentials than on Pt. These oxy species oxidized COad intermediates, bound to adjacent Pt atoms and thus discharged them for dehydrogenation of the subsequent CH3OH molecules. [ABSTRACT FROM AUTHOR]

Spin-torque nano-oscillators can emulate neurons at the nanoscale. Recent works show that the non-linearity of their oscillation amplitude can be leveraged to achieve waveform classification for an input signal encoded in the amplitude of the input voltage. Here, we show that the frequency and phase of the oscillator can also be used to recognize waveforms. For this purpose, we phase-lock the oscillator to the input waveform, which carries information in its modulated frequency. In this way, we considerably decrease the amplitude, phase, and frequency noise. We show that this method allows classifying sine and square waveforms with an accuracy above 99% when decoding the output from the oscillator amplitude, phase, or frequency. We find that recognition rates are directly related to the noise and non-linearity of each variable. These results prove that spin-torque nano-oscillators offer an interesting platform to implement different computing schemes leveraging their rich dynamical features. [ABSTRACT FROM AUTHOR]

The effect of chromium(VI) on the kinetics of disproportionation of hypochlorous acid and hypochlorite was established in the solution for the electrolytic production of chlorate. The hexavalent chromium species Cr2O72-, HCrO4- and CrO42-present in the solution catalyze the disproportionation reaction. In both the absence and presence of chromium(VI), disproportionation is a third-order reaction with respect to HClO and ClO- and a first-order reaction with respect to the hexavalent chromium species. In the presence of chromium(VI) ions, four parallel reactions probably take place in the solution i.e. uncatalyzed disproportionation and three parallel reactions catalyzed by Cr2O72-, HCrO4- and CrO42-ions. Most likely, the hexavalent chromium species do not change the sequence of elementary reactions in the disproportionation mechanism but only speed up the rate-determining step through interaction with its reactants. In the chlorate production process, as chromium(VI) concentration increases, the optimum pH which ensures the maximum rate of disproportionation is shifted to an acid environment. This is due to an increase in the concentration of the catalytically most active species HCrO4- with increasing acidity of the solution. A mathematical model of the kinetics of the chromium(VI)-catalyzed disproportionation of hypochlorite and hypochlorous acid into chlorate was set up. Good agreement was obtained between theoretical and experimental data. [ABSTRACT FROM AUTHOR]

During the coal pulverizing, the working parts of the ventilation mill are being worn by the sand particles. For this reason, the working parts are usually protected with materials resistant to wear (hardfaced/thermal sprayed coatings). The aim of this study was to evaluate the tribological performance of four different types of coatings as candidates for wear protection of the mill's working parts. The coatings were produced by using the filler materials with the following nominal chemical composition: NiFeBSi-WC, NiCrBSiC, FeCrCTiSi, and FeCrNiCSiBMn, and by using the plasma arc welding and flame and electric arc spraying processes. The results showed that Ni-based coatings exhibited higher wear resistance than Fe-based coatings. The highest wear resistance showed coating produced by using the NiFeBSi-WC filler material and plasma transferred arc welding deposition process. The hardness was not the only characteristic that affected the wear resistance. In this context, the wear rate of NiFeBSi-WC coating was not in correlation with its hardness, in contrast to other coatings. The different wear performance of NiFeBSi-WC coating was attributed to the different type and morphological features of the reinforcing particles (WC). [ABSTRACT FROM AUTHOR]

Calcium hydroxyapatite (CHA) formation was produced by biomimetic deposition on the surfaces of silica layers of the steel bands, using slightly modified simulated body fluid (SBF). The used SBF had a pH value of 7·4 and a similar ionic composition like human plasma. Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) method was used to analyse obtained phases on the surfaces of silica films after various times of sample soaking in SBF. Atomic force microscopy (AFM) investigations pointed out the mechanism of CHA nucleation. Mass changes investigations of the CHA thin films showed that the depth of CHA films was dependent on the aging time of silica substrate in SBF. [ABSTRACT FROM AUTHOR]