In vitro investigation of electrophoretically deposited bioactive hydroxyapatite/chitosan coatings reinforced by graphene

&#x110,o&#x161,ić,, Marija,Eraković,, Sanja,Janković,, Ana,Vuka&#x161,inović,-Sekulić,, Maja,Matić,, Ivana Z.,Stojanović,, Jovica,Rhee, Kyong Yop,Miš,ković Elsevier 2017 Journal of industrial and engineering chemistry Vol.47 No.-

<P><B>Abstract</B></P> <P>Graphene (Gr) and natural polymer chitosan (CS) were introduced to hydroxyapatite (HAP) to produce a three-component composite coating, which was fabricated by cathodic electrophoretic deposition on Ti substrates in an ethanol suspension. These HAP/CS/Gr coatings were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and electrochemical measurements and found that the graphene into HAP/CS composites significantly improves their morphology, thermal stability, and bioactivity. Both HAP/CS and HAP/CS/Gr composite coatings are classified as non-cytotoxic when tested against healthy peripheral blood mononuclear cells (PBMC), while antibacterial activity against <I>Staphylococcus aureus</I> and <I>Escherichia coli</I> could not be verified.</P>

First analysis of solar structures in 1.21 mm full-disc ALMA image of the Sun

Braj&#x161,a, R.,Sudar, D.,Benz, A. O.,Skokić,, I.,Bá,rta, M.,De Pontieu, B.,Kim, S.,Kobelski, A.,Kuhar, M.,Shimojo, M.,Wedemeyer, S.,White, S.,Yagoubov, P.,Yan, Y. Springer-Verlag 2018 Astronomy and astrophysics Vol.613 No.-

<P><I>Context.</I> Various solar features can be seen in emission or absorption on maps of the Sun in the millimetre and submillimetre wavelength range. The recently installed Atacama Large Millimetre/submillimetre Array (ALMA) is capable of observing the Sun in that wavelength range with an unprecedented spatial, temporal and spectral resolution. To interpret solar observations with ALMA, the first important step is to compare solar ALMA maps with simultaneous images of the Sun recorded in other spectral ranges.</P><P><I>Aims.</I> The first aim of the present work is to identify different structures in the solar atmosphere seen in the optical, infrared, and EUV parts of the spectrum (quiet Sun, active regions, prominences on the disc, magnetic inversion lines, coronal holes and coronal bright points) in a full-disc solar ALMA image. The second aim is to measure the intensities (brightness temperatures) of those structures and to compare them with the corresponding quiet Sun level.</P><P><I>Methods.</I> A full-disc solar image at 1.21 mm obtained on December 18, 2015, during a CSV-EOC campaign with ALMA is calibrated and compared with full-disc solar images from the same day in H<I>α</I> line, in He I 1083 nm line core, and with various SDO images (AIA at 170 nm, 30.4 nm, 21.1 nm, 19.3 nm, and 17.1 nm and HMI magnetogram). The brightness temperatures of various structures are determined by averaging over corresponding regions of interest in the calibrated ALMA image.</P><P><I>Results.</I> Positions of the quiet Sun, active regions, prominences on the disc, magnetic inversion lines, coronal holes and coronal bright points are identified in the ALMA image. At the wavelength of 1.21 mm, active regions appear as bright areas (but sunspots are dark), while prominences on the disc and coronal holes are not discernible from the quiet Sun background, despite having slightly less intensity than surrounding quiet Sun regions. Magnetic inversion lines appear as large, elongated dark structures and coronal bright points correspond to ALMA bright points.</P><P><I>Conclusions.</I> These observational results are in general agreement with sparse earlier measurements at similar wavelengths. The identification of coronal bright points represents the most important new result. By comparing ALMA and other maps, it was found that the ALMA image was oriented properly and that the procedure of overlaying the ALMA image with other images is accurate at the 5 arcsec level. The potential of ALMA for physics of the solar chromosphere is emphasised.</P>

Torrenticolid water mites from Korea and the Russian Far East

Pe&#x161,ić,, Vladimir,Semenchenko, Ksenia A.,Lee, Wonchoel Pensoft Publishers 2013 ZooKeys Vol.299 No.-

<P>Abstract</P><P>New records of water mites of the family Torrenticolidae Piersig, 1902 (Acari: Hydrachnidia) from streams in South Korea and the Russian Far East are presented. Detailed descriptions or redescrptions are provided for eight species of the genera <I>Torrenticola</I> Piersig, 1896 and <I>Monatractides</I> K. Viets 1926. Two species are described as new to science: <I>Torrenticola kimichungi</I><B>sp. n.</B> and <I>Monatractides abei</I><B>sp. n.</B> Five species are reported as first records from Korea: <I>Torrenticola brevirostris</I> (Halbert, 1911); <I>Torrenticola dentifera</I> Wiles, 1991; <I>Torrenticola recentis</I> Tuzovskij, 2003; <I>Torrenticola ussuriensis</I> (Sokolow, 1934); and <I>Torrenticola turkestanica</I> (Sokolow, 1926). <I>Torrenticola nipponica</I> (Enami, 1940) is reported for the first time from Russia.</P>

Analytical procedures for torsional vibration analysis of ship power transmission system

Senjanović,, Ivo,Had&#x17e,ić,, Neven,Murawski, Lech,Vladimir, Nikola,Alujević,, Neven,Cho, Dae-Seung Elsevier 2019 ENGINEERING STRUCTURES Vol.178 No.-

<P><B>Abstract</B></P> <P>In this paper two relatively simple analytical procedures for free and forced torsional vibration analysis of ship power transmission systems are developed. In the first, approximate procedure, the shaft line is modelled as a two-mass system and analytical solution of the differential equations of motion is given. In the second one, a multi degree of freedom (d.o.f.) problem of the complete propulsion system is solved by the Rayleigh-Ritz method. A special attention is paid to the determination of the contribution of each cylinder to the primary and secondary engine torques by taking into account the firing order. The application of the two procedures is illustrated in the case of a typical propulsion system of a merchant ship with a slow-speed main engine connected directly to the propeller by a relatively short shaft line. The obtained results are verified by a comparison with measurements. All classification societies require calculation of the propulsion system operating parameters, but they do not provide simplified formulae for vibration analysis. The outlined analytical procedures can be used for the estimation of torsional vibration of the shaft line in the preliminary ship design stage as well as for ships in service.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Condensed two-mass model of shaft line. Analytical solution of diff. eqs. of motion. </LI> <LI> Simplified multi-mass model of shaft line. Rayleigh-Ritz method. Analytical solution. </LI> <LI> Formulation of cylinder torque and engine primary and secondary torque. </LI> <LI> Physically based transfer factor of engine excitation to shaft response. </LI> <LI> Comparison with FEM. Verification by measurement. High accuracy. </LI> </UL> </P>

Inter-comparison of dynamic models for radionuclide transfer to marine biota in a Fukushima accident scenario

Vives i Batlle, J.,Beresford, N.A.,Beaugelin-Seiller, K.,Bezhenar, R.,Brown, J.,Cheng, J.-J.,&#x106,ujić,, M.,Dragović,, S.,Duffa, C.,Fié,vet, B.,Hosseini, A.,Jung, K.T.,Kamboj, S.,Keu Elsevier 2016 JOURNAL OF ENVIRONMENTAL RADIOACTIVITY Vol.153 No.-

<P><B>Abstract</B></P> <P>We report an inter-comparison of eight models designed to predict the radiological exposure of radionuclides in marine biota. The models were required to simulate dynamically the uptake and turnover of radionuclides by marine organisms.</P> <P>Model predictions of radionuclide uptake and turnover using kinetic calculations based on biological half-life (<I>T</I> <SUB> <I>B1/2</I> </SUB>) and/or more complex metabolic modelling approaches were used to predict activity concentrations and, consequently, dose rates of <SUP>90</SUP>Sr, <SUP>131</SUP>I and <SUP>137</SUP>Cs to fish, crustaceans, macroalgae and molluscs under circumstances where the water concentrations are changing with time. For comparison, the ERICA Tool, a model commonly used in environmental assessment, and which uses equilibrium concentration ratios, was also used. As input to the models we used hydrodynamic forecasts of water and sediment activity concentrations using a simulated scenario reflecting the Fukushima accident releases.</P> <P>Although model variability is important, the intercomparison gives logical results, in that the dynamic models predict consistently a pattern of delayed rise of activity concentration in biota and slow decline instead of the instantaneous equilibrium with the activity concentration in seawater predicted by the ERICA Tool. The differences between ERICA and the dynamic models increase the shorter the <I>T</I> <SUB> <I>B1/2</I> </SUB> becomes; however, there is significant variability between models, underpinned by parameter and methodological differences between them.</P> <P>The need to validate the dynamic models used in this intercomparison has been highlighted, particularly in regards to optimisation of the model biokinetic parameters.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Comparison of 7 dynamic models for radionuclide transfer in marine biota with the ERICA Tool. </LI> <LI> <SUP>90</SUP>Sr, <SUP>131</SUP>I, <SUP>137</SUP>Cs in fish, crustaceans, algae and molluscs in a Fukushima scenario. </LI> <LI> Consistent pattern of delayed uptake and slow turnover by the dynamic models. </LI> <LI> Differences between ERICA and dynamic models increase with biological half-life. </LI> <LI> Significant variability between models linked to parameter and methodology differences. </LI> </UL> </P>

Some aspects of structural modelling and restoring stiffness in hydroelastic analysis of large container ships

Senjanović,, Ivo,Vladimir, Nikola,Tomić,, Marko,Had&#x17e,ić,, Neven,Malenica, &#x160,ime Taylor Francis 2014 SHIPS AND OFFSHORE STRUCTURES Vol.9 No.2

Further studies on water mites from Korea, with description of two new species ( Acari , Hydrachnidia )

Pe&#x161,ić,, Vladimir,Semenchenko, Ksenia A.,Lee, Wonchoel Pensoft Publishers 2015 ZooKeys Vol.507 No.-

<P>Abstract</P><P>New records of water mites (Acari: Hydrachnidia) from streams in South Korea are presented. Two species are described as new to science: <I>Torrenticolaneodentifera</I><B>sp. n.</B> (Torrenticolidae) and <I>Atractidesermilovi</I><B>sp. n.</B> (Hygrobatidae). Five species are reported as first records for Korea: Wandesia (Wandesia) reducta Tuzovskij, 1987, Wandesia (Wandesia) cf.rara Tuzovskij, 1990, Sperchon (Sperchon) orientalis Tuzovskij, 1990, Feltria (Feltria) kuluensis Tuzovskij, 1988 and Atractides (Atractides) constrictus (Sokolow, 1934). The latter species is redescribed and elevated to species rank based on new material from the Russian Far East.</P>

Synthesis and Magnetic Properties of Hematite Particles in a “Nanomedusa” Morphology

Lee, Jin Bae,Kim, Hae Jin,Lu&#x17e,nik, Janez,Jelen, Andreja,Pajić,, Damir,Wencka, Magdalena,Jaglič,ić,, Zvonko,Meden, Anton,Dolin&#x161,ek, Janez Hindawi Limited 2014 Journal of nanomaterials Vol.2014 No.-

<P>We present the synthesis, characterization, and magnetic properties of hematite particles in a peculiar “nanomedusa” morphology. The particles were prepared from an iron-silica complex by a hydrothermal process in a solution consisting of ethyl acetate and ethanol. The particles’ morphology, structure, and chemical composition were investigated by transmission electron microscopy, powder X-ray diffraction, and scanning electron microscope equipped with an energy-dispersive X-ray spectrometer. The “hairy” particles consist of a spherical-like core of about 100 nm diameter and fibrous exterior composed of thin “legs” of 5 nm diameter grown along one preferential direction. The particles’ cores are crystalline and undergo a magnetic phase transition to a weakly ferromagnetic state at a temperature of 930 K that matches reasonably the Néel temperature of bulk hematite. However, unlike bulk hematite that undergoes Morin transition to an antiferromagnetic state around room temperature and small hematite nanoparticles that are superparamagnetic, the “nanomedusa” particles remain weakly ferromagnetic down to the lowest investigated temperature of 2 K. Each particle thus represents a nanodimensional “hairy” ferromagnet in a very broad temperature interval, extending much above the room temperature. Such high-temperature ferromagnetic nanoparticles are not frequently found among the nanomaterials.</P>

Expanding large global solutions of the equations of compressible fluid mechanics

Had&#x17e,ić,, Mahir,Jang, Juhi Springer-Verlag 2018 Inventiones mathematicae Vol.214 No.3

Vibration analysis of thin circular plates with multiple openings by the assumed mode method

Senjanović,, Ivo,Had&#x17e,ić,, Neven,Vladimir, Nikola SAGE Publications 2017 Proceedings of the Institution of Mechanical Engin Vol.231 No.1