bluuebunny/crossref_metadata_2025 huggingface dataset:
Fabrication and Characterization of Ni-CNT Composites by Electrical Explosion of Wire in Different Liquids
Authors: Thuyet-Nguyen M. ,   Maithili-Biswas, Kim W.J. , Kim J.-C.
Published: July 2017

In this study, Ni-CNT powders and colloids were synthesized via the Electrical explosion of wire (EEW) in different liquid conditions. The influence of ambient solvents (D.I. Water, ethanol, methanol, acetone and ethylene-glycol) on characteristics of the as-synthesized Ni-CNT was investigated. The morphology and size were observed by field emission scanning electron microscopy (FE-SEM). The Ni particles were spherical or near spherical shape. The phase of the composite powders analyzed via X-ray diffraction demonstrate the presence of CNTs in composite powders is not affect the structure of Ni. However, the phase of the composites was changed based on the changing of liquid conditions. Stability of colloids was investigated by Turbiscan technique. Magnetic properties were also investigated by Vibrating sample magnetometer (VSM) at room temperature. The as-synthesized composite powders revealed a ferromagnetic characteristic material.
Effect of Wetting Agent and Carbide Volume Fraction on the Wear Response of Aluminum Matrix Composites Reinforced by WC Nanoparticles and Aluminide Particles
Authors: Lekatou A. , Gkikas N. , Karantzalis A.E. , Kaptay G. , Gacsi Z. , Baumli P. , Simon A.
Published: July 2017

Aluminum matrix composites were prepared by adding submicron sized WC particles into a melt of Al 1050 under mechanical stirring, with the scope to determine: (a) the most appropriate salt flux amongst KBF4, K2TiF6, K3AlF6and Na3AlF6for optimum particle wetting and distribution and (b) the maximum carbide volume fraction (CVF) for optimum response to sliding wear. The nature of the wetting agent notably affected particle incorporation, with K2TiF6providing the greatest particle insertion. A uniform aluminide (in-situ) and WC (ex-situ) particle distribution was attained. Two different sliding wear mechanisms were identified for low CVFs (≤1.5%), and high CVFs (2.0%), depending on the extent of particle agglomeration.
Effect of Local Strain Distribution of Cold-Rolled Alloy 690 on Primary Water Stress Corrosion Crack Growth Behavior
Authors: Kim S.-W. , Ahn T.-Y. , Lim Y.-S. , Hwang S.-S.
Published: July 2017

This work aims to study the stress corrosion crack growth behavior of cold-rolled Alloy 690 in the primary water of a pressurized water reactor. Compared with Alloy 600, which shows typical intergranular cracking along high angle grain boundaries, the cold-rolled Alloy 690, with its heterogeneous microstructure, revealed an abnormal crack growth behavior in mixed mode, that is, in transgranular cracking near a banded region, and in intergranular cracking in a matrix region. From local strain distribution analysis based on local mis-orientation, measured along the crack path using the electron back scattered diffraction method, it was suggested that the abnormal behavior was attributable to a heterogeneity of local strain distribution. In the cold-rolled Alloy 690, the stress corrosion crack grew through a highly strained area formed by a prior cold-rolling process in a direction perpendicular to the maximum principal stress applied during a subsequent stress corrosion cracking test.
Microstructure and Magnetic Properties of NdFeB Sintered Magnets Diffusion-Treated with Cu/Al Mixed Dyco Alloy-Powder
Authors: Lee M.-W. , Bae K.-H. , Lee S.-R. , Kim H.-J. , Jang T.-S.
Published: July 2017

We investigated the microstructural and magnetic property changes of DyCo, Cu + DyCo, and Al + DyCo diffusion-treated NdFeB sintered magnets. The coercivity of all diffusion treated magnet was increased at 880ºC of 1stpost annealing(PA), by 6.1 kOe in Cu and 7.0 kOe in Al mixed DyCo coated magnets, whereas this increment was found to be relatively low (3.9 kOe) in the magnet coated with DyCo only. The diffusivity and diffusion depth of Dy were increased in those magnets which were treated with Cu or Al mixed DyCo, mainly due to comparatively easy diffusion path provided by Cu and Al because of their solubility with Ndrich grain boundary phase. The formation of Cu/Al-rich grain boundary phase might have enhanced the diffusivity of Dy-atoms. Moreover, relatively a large number of Dy atoms reached into the magnet and mostly segregated at the interface of Nd2Fe14B and grain boundary phases covering Nd2Fe14B grains so that the core-shell type structures were developed. The formation of highly anisotropic (Nd, Dy)2Fe14B phase layer, which acted as the shell in the core-shell type structure so as to prevent the reverse domain movement, was the cause of enhancing the coercivity of diffusion treated NdFeB magnets. Segregation of cobalt in Nd-rich TJP followed by the formation of Co-rich phase was beneficial for the coercivity enhancement, resulting in the stabilization of the metastable c-Nd2O3phase.
Self-Consolidation Mechanism of Ti5Si3 Compact Obtained by Electro-Discharge-Sintering Directly from Physically Blended Ti-37.5 at.% Si Powder Mixture
Authors: Chang S.Y. , Cheon Y.W. , Yoon Y.H. , Kim Y.H. , Kim J.Y. , Lee Y.K. , Lee W.H.
Published: July 2017

Characteristics of electro-discharge-sintering of the Ti-37.5at.% Si powder mixture was investigated as a function of the input energy, capacitance, and discharge time without applying any external pressure. A solid bulk of Ti5Si3was obtained only after in less than 129 μsec by the EDS process. During a discharge, the heat is generated to liquefy and alloy the particles, and which enhances the pinch pressure can condensate them without allowing a formation of pores. Three step processes for the self-consolidation mechanism during EDS are proposed; (a) a physical breakdown of oxide film on elemental as-received powder particles, (b) alloying and densifying the consolidation of powder particles by the pinch pressure, and (c) diffusion of impurities into the consolidated surface.
Effect of Strut Thickness on Room and High Temperature Compressive Properties of Block-Type Ni-Cr-Al Powder Porous Metals
Authors: Kang B.-H. , Park M.-H. , Lee K.-A.
Published: July 2017

This study investigated the effect of strut thickness on the room and high temperature compressive properties of block-type Ni-Cr-Al powder porous metals with ~3000 μm pore size manufactured using a new powder process. Two block-type Ni-Cr-Al porous metals with different strut thicknesses were manufactured. The strut thicknesses of two block foams were 340 μm (A) and 383 μm (B), respectively. Room temperature, 500°C, 650°C and 800°C compressive tests were performed. The compressive results identified typical elastic, plateau and densification regions of foam material in all temperature conditions. Regardless of the strut thickness, compressive strength (maximum peak stress) decreased as deformation temperature increased. In all deformation temperature ranges, the compressive strength measured higher in the porous metal with greater strut thickness (B). The high temperature deformation behavior of powder porous metal was confirmed to be affected by the structural factor and microstructural factor of the porous metal. With the findings described above, this study also discussed the high temperature deformation mechanism of the Ni-Cr-Al metal foam based on fracture surfaces after the high temperature compressions.
Understanding the Oxide Dispersion Behavior of Yttria in Metal Matrix of MA956 Alloy through High-Energy Milling and Hot Press Sintering
Authors: Swain B. , Han D. , Kim G.-H. , Kong M.-S. , Ahn B.
Published: July 2017

MA956 (Fe-Cr-Al) alloy powder was high-energy ball milled with various amount of yttria contents (1,2,3, and 4 wt.%) to fabricate an oxide dispersion strengthened alloy. The milled powders were then consolidated using hot press sintering at 1150°C. The surface morphology and crystal structure of MA956 powder during the high-energy milling depending on the yttria contents was investigated using particle size analysis, X-ray diffraction, and scanning electron microscopy. The microstructural analysis of sintered alloy was performed using transmission electron microscopy and energy dispersive spectroscopy to evaluate the dispersion behavior of yttrium oxide. The results showed that, as yttria contents increased, the oxide particles became finer and are uniformly distributed during the high-energy milling. However, after the sintering, the oxide particles were coarsened with more than 3 wt.% of yttria addition.
Oxidation Behavior of Steel With Cr Content and Water Flow Rate
Authors: Kim D.-J. , Kim K.M. , Shin J.H. , Cheong Y.M. , Lee E.H. , Lee G.G. , Kim S.W. , Kim H.P. , Choi M.J. , Lim Y.S. , Hwang S.S.
Published: July 2017

Fast water flow facilitates ferrous ion transport leading to flow accelerated corrosion (FAC) of carbon steel and the possibility of a large accident through a failure of a secondary pipe in a nuclear power plant. Ion transport is directly linked to oxide properties such as the thickness, chemical composition and porosity. This work deals with a precise observation of the cross section of the corroded specimen focusing on an oxide passivity and its thickness using SEM (scanning electron microscope) and TEM (transmission electron microscope) as well as an apparent weight loss and a surface observation for the specimens corroded using a rotating cylindrical electrode autoclave system in pure water of pH 7 at 150°C having dissolved oxygen below 1 ppb within a flow rate range of 0 to 10 m/s. The Cr content in steel was changed from 0.02 to 2.4 wt%. Increasing the Cr content in the alloy, the FAC rate and oxide thickness decreased. The oxide porosity tends to decrease with the Cr content and immersion time owing to the development of Cr containing oxide. The oxidation behavior is not changed with the immersion time.
Rapid Synthesis of Gold Nano-Particles Using Pulse Waved Potential in a Non-Aqueous Electrolyte
Authors: Jang J.G. , Lee J.-O. , Lee C.K.
Published: July 2017

Rapid synthesis of gold nanoparticles (AuNPs) by pulsed electrodeposition was investigated in the non-aqueous electrolyte, 1-ethyl-3-methyl-imidazoliumbis(trifluoro-methanesulfonyl)imide ([EMIM]TFSI) with gold trichloride (AuCl3). To aid the dissolution of AuCl3, 1-ethyl-3-methyl-imidazolium chloride ([EMIM]Cl) was used as a supporting electrolyte in [EMIM]TFSI. Cyclic voltammetry experiments revealed a cathodic reaction corresponding to the reduction of gold at −0.4 V vs. Pt-QRE. To confirm the electrodeposition process, potentiostatic electrodeposition of gold in the non-aqueous electrolyte was conducted at −0.4 V for 1 h at room temperature. To synthesize AuNPs, pulsed electrodeposition was conducted with controlled duty factor, pulse duration, and overpotential. The composition, particle-size distribution, and morphology of the AuNPs were confirmed by field-emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), and transmission electron microscopy (TEM). The electrodeposited AuNPs were uniformly distributed on the platinum electrode surface without any impurities arising from the non-aqueous electrolyte. The size distribution of AuNPs could be also controlled by the electrodeposition conditions.
Effect of Mechanical Activation on the In Situ Formation of TiB2 Particulates in the Powder Mixture of TiH2 and FeB
Authors: Huynh X.-K. , Kim B.-W. , Kim J.S.
Published: July 2017

The in situ formation of TiB2particulates via an interface reaction between Ti and FeB powders was studied. The effects of mechanical activation by high-energy milling on the decomposition of TiH2and the interface reactions between Ti and FeB powders to form TiB2were investigated. Powder mixtures were fabricated using planetary ball-milling under various milling conditions. The specific ball-milling energy was calculated from the measured electrical power consumption during milling process. High specific milling energy (152.6 kJ/g) resulted in a size reduction and homogeneous dispersion of constituent powders. This resulted in a decrease in the decomposition temperature of TiH2and an increase in the formation reaction of TiB2particulates in the Fe matrix, resulting in a homogeneous microstructure of nanoscale TiB2evenly distributed within the Fe matrix. In contrast, the powder mixture milled with low specific milling energy (36.5 kJ/g) showed an inhomogeneous microstructure composed of relatively large Fe-Fe2B particles surrounded by a thin layer of Fe-TiB2within a finely dispersed Fe-TiB2matrix region.
Fabrication of Cu-Based SiC Composites by Spark Plasma Sintering of Cu-Nitrate Coated SiC Powders
Authors: Jeong Y.-K. , Kim Y.S. , Oh S.-T.
Published: July 2017

An optimum route to fabricate the Cu-based SiC composites with homogeneous microstructure was investigated. Three methods for developing the densified composites with sound interface between Cu and SiC were compared on the basis of the resulting microstructures. Starting with three powder mixtures of elemental Cu and SiC, elemental Cu and PCS coated SiC or PCS and Cunitrate coated SiC was used to obtain Cu-based SiC composites. SEM analysis revealed that the composite fabricated by spark plasma sintering using elemental SiC and Cu powder mixture showed inhomogeneous microstructure. Conversely, dense microstructure with sound interface was observed in the sintered composites using powder mixture of pre-coated PCS and Cu-nitrate onto SiC. The relationship between powder processing and microstructure was discussed based on the role of coating layer for the wettability
Great Civilizations Population Increase/Decrease Factor
Authors: Băncilă Andi Mihail
Published: July 2017

Demographic changes that currently affect the planet are not fully new, they have continued throughout history, managing to influence geographical areas and making changes to individuals’ lifestyle. The phenomenon of international migration has become a topical issue in 2015 with the increasing number of asylum seekers on the territory of the European Union. This special event raised new questions about the socio-economic evolution of the European continent, with problems being signaled both from the perspective of newcomers and permanent residents of this space. The main task that the political authorities of the member states of the community block have over the next years is to identify a solution through which to achieve appropriate and long-term integration of newcomers, many of them belonging to different cultures of the majority population.
Influence of Low-Temperature Plasma Treatment on The Liquid Filtration Efficiency of Melt-Blown PP Nonwovens in The Conditions of Simulated Use of Respiratory Protective Equipment
Authors: Majchrzycka Katarzyna , Okrasa Małgorzata , Brochocka Agnieszka , Urbaniak-Domagała Wiesława
Published: July 2017

Filtering nonwovens produced with melt-blown technology are one of the most basic materials used in the construction of respiratory protective equipment (RPE) against harmful aerosols, including bio- and nanoaerosols. The improvement of their filtering properties can be achieved by the development of quasi-permanent electric charge on the fibres. Usually corona discharge method is utilized for this purpose. In the presented study, it was assumed that the low-temperature plasma treatment could be applied as an alternative method for the manufacturing of conventional electret nonwovens for the RPE construction. Low temperature plasma treatment of polypropylene nonwovens was carried out with various process gases (argon, nitrogen, oxygen or air) in a wide range of process parameters (gas flow velocity, time of treatment and power supplied to the reactor electrodes). After the modification, nonwovens were evaluated in terms of filtration efficiency of paraffin oil mist. The stability of the modification results was tested after 12 months of storage and after conditioning at elevated temperature and relative humidity conditions. Moreover, scanning electron microscopy and ATR-IR spectroscopy were used to assess changes in surface topography and chemical composition of the fibres. The modification of melt-blown nonwovens with nitrogen, oxygen and air plasma did not result in a satisfactory improvement of the filtration efficiency. In case of argon plasma treatment, up to 82% increase of filtration efficiency of paraffin oil mist was observed in relation to untreated samples. This effect was stable after 12 months of storage in normal conditions and after thermal conditioning in (70 ± 3)°C for 24 h. The use of low-temperature plasma treatment was proven to be a promising improvement direction of filtering properties of nonwovens used for the protection of respiratory tract against harmful aerosols.
Bronchial Mucus as a Complex Fluid: Molecular Interactions and Influence of Nanostructured Particles on Rheological and Transport Properties
Authors: Odziomek Marcin , Kalinowska Martyna , Płuzińska Aleksandra , Rożeń Antoni , Sosnowski Tomasz R.
Published: July 2017

Transport properties of bronchial mucus are investigated by two-stage experimental approach focused on: (a) rheological properties and (b) mass transfer rate through the stagnant layer of solutions of mucus components (mucine, DNA, proteins) and simulated multi-component mucus. Studies were done using thermostated horizontal diffusion cells with sodium cromoglycate and carminic acid as transferred solutes. Rheological properties of tested liquids was studied by a rotational viscometer and a cone-plate rheometer (dynamic method). First part of the studies demonstrated that inter-molecular interactions in these complex liquids influence both rheological and permeability characteristics. Transfer rate is governed not only by mucus composition and concentration but also by hydrophobic/hydrophilic properties of transported molecules. Second part was focused on the properties of such a layer in presence of selected nanostructured particles (different nanoclays and graphene oxide) which may be present in lungs after inhalation. It was shown that most of such particles increase visco-elasticity of the mucus and reduce the rate of mass transfer of model drugs. Measured effects may have adverse impact on health, since they will reduce mucociliary clearance in vivo and slow down drug penetration to the bronchial epithelium during inhalation therapy.
Numerical Analysis of The Effect of Hydrodynamics and Operating Conditions on Biodiesel Synthesis in a Rotor-Stator Spinning Disk Reactor
Authors: Wen Zhuqing , Petera Jerzy
Published: July 2017

A rotor-stator spinning disk reactor for intensified biodiesel synthesis is described and numerically simulated in the present research. The reactor consists of two flat disks, located coaxially and parallel to each other with a gap ranging from 0.1 mm to 0.2 mm between the disks. The upper disk is located on a rotating shaft while the lower disk is stationary. The feed liquids, triglycerides (TG) and methanol are injected into the reactor from centres of rotating disk and stationary disk, respectively. Fluid hydrodynamics in the reactor for synthesis of biodiesel from TG and methanol in the presence of a sodium hydroxide catalyst are simulated, using convection-diffusion-reaction multicomponent transport model with the CFD software ANSYS©Fluent v. 13.0. Effect of operating conditions on TG conversion is particularly investigated. Simulation results indicate that there is occurrence of back flow close to the stator at the outlet zone. Small gap size and fast rotational speed generally help to intensify mixing among reagents, and consequently enhance TG conversion. However, increasing rotational speed of spinning disk leads to more backflow, which decreases TG conversion. Large flow rate of TG at inlet is not recommended as well because of the short mean residence time of reactants inside the reactor.
The Effect of Disaccharide Concentration in a Liquid Binder on The Mechanisms and Kinetics of Disc Granulation
Authors: Obraniak Andrzej , Gluba Tadeusz
Published: July 2017

Analysis of granulation kinetics was carried out using a laboratory disc granulator with a diameter D of 0.5 m. A liquid binder was delivered to the tumbling bed at a constant flow rate with a nozzle generating droplets with a size of approx. 4-5 mm. Fine-grained chalk was used as a model of raw material and water or disaccharide solution with concentrations of 20 - 40% as a wetting liquid. Different times of droplet delivery ranging from 2 to 6 min were utilized. Granulometric composition of the bed for selected lengths of process, bed moisture and the moisture of individual size-fractions were assessed. Mass of granulated material, which was transferred from nuclei fraction to other size fractions was determined on the basis of mass balance analysis and the assessment of liquid migration between fractions. The influence of disaccharide concentration in wetting liquid on the aforementioned phenomena was also examined.
External Mass Transfer Model for Hydrogen Peroxide Decomposition by Terminox Ultra Catalase in a Packed-Bed Reactor
Authors: Grubecki Ireneusz
Published: July 2017

It is known that external diffusional resistances are significant in immobilized enzyme packed-bed reactors, especially at large scales. Thus, the external mass transfer effects were analyzed for hydrogen peroxide decomposition by immobilized Terminox Ultra catalase in a packed-bed bioreactor. For this purpose the apparent reaction rate constants, kP, were determined by conducting experimental works at different superficial velocities, U, and temperatures. To develop an external mass transfer model the correlation between the Colburn factor, JD, and the Reynolds number, Re, of the type JD = K Re(n-1) was assessed and related to the mass transfer coefficient, kmL. The values of K and n were calculated from the dependence (am kp-1 - kR-1) vs. Re-1 making use of the intrinsic reaction rate constants, kR, determined before. Based on statistical analysis it was found that the mass transfer correlation JD = 0.972 Re-0.368 predicts experimental data accurately. The proposed model would be useful for the design and optimization of industrial-scale reactors.
On Co-Creativity in Playful Classroom Activities
Authors: Schmoelz Alexander
Published: July 2017

Recent research points to the essential role of creativity in coping with and acting in a changing world. It has been shown that individual, collaborative and communal efforts are a core capacity for acting in and coping with ever changing circumstances, such that a novel emphasis on cocreativity has arisen. Yet there is very little research on how to provide occasions for co-creativity in classrooms and so the research problem focuses on enabling co-creativity. Therefore, a playful pedagogical design was created and facilitated in classroom. The qualitative data collection methods involved narrative-Socratic dialogues with teachers and students, field notes, and gameplay videography. The Narrative-Structural Method was used to analyze the research material. The main results show that playful classroom activities provide an occasion for co-creative reframing's, engaging in dialogue, expressing emotions, and co-creating a shared story that is rich in co-determined actions. In conclusion, the pedagogical implications of the results are that classroom activities for co-creativity may facilitate mixed playful pedagogies and empty content spaces, so that children and young people can playfully identify, explore and negotiate shared topics that are novel and meaningful to themselves and others.
Key Policy Rate as the Main or Additional Instrument of Inflation Targeting Strategy in Serbia
Authors: Furtula Srđan , Kostić Milan
Published: July 2017

In achieving price stability as the primary objective of monetary policy, the National Bank of Serbia uses the key policy rate as the main instrument of monetary policy, while other instruments have a supporting role - contribute to a smooth transmission of the key policy rate on the market, as well as the development of financial markets. However, because the conditions in which economic and financial system of the Republic of Serbia works, transmission mechanism of monetary policy is conducted mainly through the exchange rate channel, while the channel of interest rates almost did not work. The great impact the exchange rate channel is determined by the great influence of the single currency euro and the ECB on our country. Therefore, the aim of this paper is to analyse the efficiency of the key policy rate as a monetary policy instrument, because in recent years the primary instrument receives a secondary character in the monetary regulation.
Applying the Moodle Platform in Online Student Self-Assessment
Authors: Stanković Jovica , Milovanović Slavoljub , Radović Ognjen
Published: July 2017

Taking into consideration the importance of information and communications technology in higher education both as part of the teaching and grading process, but also the limitations in its application in higher education in the Republic of Serbia, this paper outlines the possibilities which the Moodle platform offers for the definition and use of online self-assessment tests and quizzes in the preparation and simulation of the entrance exam for the Faculty of Economics of the University of Niš. To indicate the importance of egrading for the increase in the effectiveness of learning, the paper analyses the number of created accounts and the number of visits, while a statistical analysis of the candidates′ results on the simulated entrance exam, from 2014 to 2016, was used to test the hypothesis on the significance of formative assessment for effective learning. The obtained t-test results indicate that formative assessment in this specific instance contributes to the improvement of the candidates’ learning process and that the application of such a means of student self-assessment in other areas of study would significantly contribute to the increase in the effectiveness of learning. On the other hand, statistical analyses of individual responses to questions represent a significant source of feedback for teachers, which can be used for the purpose of redefining tests.
Review of Aeronautical Fatigue Investigations in Poland (2013-2014)
Authors: Niepokólczycki Antoni , Leski Andrzej , Dragan Krzysztof
Published: July 2017

This review was presented on the 34 Conference of the International Committee on Aeronautical Fatigue and Structural Integrity, Helsinki, Finland, June 1-2, 2015. It contains description of main works and investigations in fatigue of aircraft structures performed in Poland during the years 2013 and 2014.
Lightning Strike Protection of Aircraft Composite Structures: Analysis and Comparative Study
Authors: Katunin Andrzej
Published: July 2017

Lightning strikes are a serious problem during operation of aircraft due to the increasing applicability of polymeric composites in aircraft structures and the weak electrical conducting properties of such structures. In composite structures, lightning strikes may cause extended damage sites which require to be appropriately maintained and repaired leading to increased operational costs. In order to overcome this problem various lightning strike protection solutions have been developed. Some of them are based on the immersion of metallic elements and particles while others use novel solutions such as intrinsically conductive polymers or other types of highly conductive particles including carbon nanotubes and graphene. The concept of fully organic electrically conductive composites based on intrinsically conductive polymers is currently being developed at the Silesian University of Technology. The results obtained in numerous tests, including concerning electrical conductivity and the capability to carry on high-magnitude electrical charges as well as certain operating properties need to be compared with existing solutions in lightning strike protection of aircraft. The following study presents the properties of the material developed for lightning strike protection and a comparative study with other solutions.
Electropolishing Procedure Dedicated to In-Depth Stress Measurements with X-Ray Diffractometry
Authors: Gadalińska Elżbieta , Wronicz Wojciech
Published: July 2017

Electropolishing is the sole reliable method of removing the outer layer of the specimen without changing its stress state. This feature of the electropolishing procedure allows researchers to investigate the in-depth stress distribution. Developing of the method in a diffraction laboratory is crucial because there is no universal theory for the electropolishing procedure allowing the removal of the layers of different thickness. This is due to the multiplicity of different factors affecting the electropolishing results. A factor of vital importance from the point of view of indepth stress measurements is the thickness of the electropolishing layer. Hence the importance of the procedures for the electropolishing of a layer of a precisely defined thickness.

This work deals with the problem of the selection of the parameters in the electropolishing process for two types of materials: stainless steel and aluminium alloy. The tests of mutual correlation of current intensity, voltage applied and time of the procedure and its results are presented in the paper.
The In-Depth Stress Distribution for 1H13 Specimen after Cutting
Authors: Gadalińska Elżbieta , Wronicz Wojciech , Malicki Maciej
Published: July 2017

Measuring the in-depth stress state is of vital importance for materials scientists. Strain gauges methods are capable of yielding information only about the surface stress state. Diffraction methods using synchrotron or neutron radiation, which allow totally non-destructive stress measurements inside the material, are not widely available. In this context, the best widely available method combines the X-ray diffraction stress measurements and gradual removal of the outer layer by means of electropolishing. Here, this method was applied to the specimen made of 1H13 stainless steel cut with under water on a corundum cut-off wheel. The idea was to investigate how deeply an additional stress state resulting from cutting was introduced and whether the technique of combining of X-ray diffractometry and electropolishing can be used widely for determining the stress state inside the specimen.
Approach to Critical Crack Opening Displacement Modeling of Damage in Metal Sheets after Composite Patch Bonded Repair
Authors: Sałacinski Michał , Leski Andrzej , Stefaniuk Michał
Published: July 2017

The paper proposes a method of calculating the maximum displacement in the aircraft metal structure repaired by CPBR (bonded composite patch repair).

The calculations were made based on specimens. The specimens were prepared according to the current requirements used in aviation. The 2024-T3 alloy metal sheet was a structure. To repair the structure used the boron-epoxy composite patch in prepreg technology was used.

The metal structure was modeled as an isotropic elastic body. The metal structure coated with the composite patch was modeled as an orthotropic structure. Based on this, the stress was determined in the metal structure.

The size opening displacement in the metal structure was determined based on the model of linear elastic fracture mechanics for the plane stress state.

The calculation results were verified by measuring the displacement in laboratory conditions.

The laboratory tests made it possible to demonstrate the accuracy of the proposed approach.
Effect of seed collection and site altitude on the growth and genetic variability of early and late flushing provenances of Norway spruce tested in the IPTNS-IUFRO 1964/68 site in Poland
Authors: Masternak Katarzyna
Published: July 2017

The growth characteristics and the genetic variability of 23 population of Norway spruce tested in the largest international comparative experiments IPTNS-IUFRO 1964/68 in Krynica were analysed. The studied populations belong to early and late flushing provenances from Alpine, Carpathian and north-eastern range of occurrence of species. The height, diameter at breast height (DBH) and genetic diversity of 79 trees were examined using random amplified polymorphism DNA (RAPD) technique. The mean spruce height at the age of 45 years was 17.5 m and the DBH 20.4 cm. The average and the effective number of alleles per locus calculated for all studied populations was 0.90 and 1.20, respectively. The expected heterozygosity was 0.10. The obtained results show statistically significant relationship of the parameters of genetic variability of Norway spruces and the type of seed collection from which the IUFRO experience was established. It was found that the genetic variability of the studied population depends on the longitude and height above sea level of mother stands. No significant correlation was found between the type of seed collection and location of mother stands and height and DBH of Norway spruce. Also the growth characteristics (height and the DBH) of trees do not depend on their genetic variability.
Variability of morphological needle traits of Scots pine (Pinus sylvestris L.) among populations from mountain and lowland regions of Poland
Authors: Łabiszak Bartosz , Lewandowska-Wosik Anetta , Pawlaczyk Ewa Maria , Urbaniak Lech
Published: July 2017

The main goal of this work was to examine interpopulational needle traits variability of Scots pine (Pinus sylvestris L.) from four mountain, one foothill and three lowland, natural populations located in Poland. This choice of locations was motivated by the presumed different origins of mountainous populations and the necessity to demonstrate how closely they are related to lowland populations. Variation in the studied populations was determined using seven morphological traits of needles: 1 - needle length, 2 - number of stomatal rows on the flat side of a needle, 3 - number of stomata per 2 mm of needle length on the flat side, 4 - number of stomatal rows on the convex side of a needle, 5 - number of stomata per 2 mm of needle length on the convex side, 6 - number of serrations per 2 mm of the needle length on the left side and 7 - number of serrations per 2 mm of the needle length on the right side. Biometric data were analysed statistically, and it was found that (i) needle traits differentiate studied populations; (ii) the postulated division of the population into two groups is reflected in the obtained results; and (iii) a particularly strong relationship was found between two relict pine populations from the Pieniny (Sokolica, Kazalnica, Czertezik) and Tatra Mts. (Wielke Koryciska), which may be the result of the common origins and history of these two populations
Synecology of Cutandia maritima (L.) Barbey, a rare psammophytic species along the Montenegrin Coast (East Adriatic Coast)
Authors: Stešević Danijela , Bubanja Nada , Caković Danka , Jogan Nejc , Luković Milica , Šilc Urban
Published: July 2017

Cutandia maritima is a circum-Mediterranean species that inhabits sandy dunes along the coast line. It is fairly frequent on the western Adriatic coast but fairly rare and possibly even non-native in the east. In Croatia, it was discovered in 1990 in Crnika Bay on the island of Rab, which was considered until 2005 to be the only site on the eastern Adriatic coast from the Gulf of Trieste in the north to Corfu in the south. In 2009, the species was briefly reported for Velika plaža (Long Beach) in Ulcinj (Montenegro) but without details about the habitat type and synecology. The aim of this paper is thus to provide a deeper insight into the ecology and synecology of C. maritima in the eastern Adriatic part of the distribution area. On Velika plaža in Ulcinj, the species was found along the whole sea-inland gradient of sand dunes, in various types of vegetation: [1210] - annual vegetation of drift lines, [2110] - embryonic shifting dunes, [2120] - shifting dunes with Ammophila arenaria (white dunes), [2220] - dunes with Euphorbia terracina, [2130*] - fixed coastal dunes with herbaceous vegetation (grey dunes), and also [2190] - humid dune slacks.
Grassland vegetation of Hodrušská hornatina highland in Central Slovakia
Authors: Klimantová Alexandra
Published: July 2017

This paper is focused on the grassland communities in Hodrušská hornatina highland, Central Slovakia. We studied grasslands at 153 sites during the vegetation periods of 2013-2015 and recorded 303 species of vascular plants in the studied localities. The species richness ranged from 16 to 66 taxa per relevé. Data analysis (TWINSPAN, DCA) grouped the relevés into eight clusters. These clusters include five associations from three alliances: Holcetum lanati (Deschampsion cespitosae), Pastinaco sativae-Arrhenatherum elatioris, Alchemillo- Arrhenatheretum elatioris, Anthoxantho odorati-Agrostietum tenuis (all from Arrhenatherion elatioris) and Onobrychido viciifoliae-Brometum erecti (Bromion erecti). The other three clusters represent the transitional and successional stages of the communities listed above. A brief description of syntaxa is given. At some sites, the threatened, rare or protected taxa of Slovakia occurred as well, one from each of the categories of Critically Endangered and Vulnerable, nine species of the Nearly Threatened and six species from the category of Least Concerned.
Phytosociological analysis of montanesubalpine dwarf willow shrub communities in the Julian Alps and on the Trnovski gozd plateau (NW and W Slovenia)
Authors: Dakskobler Igor , Surina Boštjan
Published: July 2017

By means of a phytosociological analysis of 72 relevés of montane-subalpine shrub communities with dominating Rhododendron hirsutum, Salix waldsteiniana, S. glabra and S. appendiculata from the Julian Alps and the the Trnovski Gozd Plateau and by comparing them with similar communities elsewhere in the Alps and the Dinaric Alps we described a new association Laserpitio peucedanoidis-Salicetum waldsteinianae, a new subassociation Rhododendretum hirsuti vaccinietosum myrtilli, two new subassociations of the association Dryado-Rhodothamnetum chamaecisti that had recently been described in the Dolomites (-caricetosum firmae, -salicetosum waldsteinianae), as well as a new association Heliospermo pusillae-Rhododendretum hirsuti. We classified the glabrous willow community in the study area into a new association Homogyno sylvestris- Salicetum glabrae and proposed a new name - Rhododendro hirsuti-Salicetum appendiculatae for the large-leaved willow community, which we subdivided into two geographical variants: var. geogr. Paederota lutea (Julian Alps, Trnovski Gozd Plateau) and var. geogr. Hypericum grisebachii (Liburnian Karst).
Nomenclatural remarks to the classification of plant communities along post-fire succession
Authors: Kavgacı Ali , Šilc Urban , Bașaran Saime , Marinšek Aleksander , Bașaran Mehmet Ali , Košir Petra , Balpinar Neslihan , Arslan Münevver , Denli Özge , Čarni Andraž
Published: July 2017

This paper contains the original diagnoses of new syntaxa and typifications of existing names of syntaxa from paper “Classification of plant communities along post-fire succession in Pinus brutia stands in southern Antalya (Turkey)” that was published in Turkish Journal of Botany. As journal has only on-line version according to ICPN descriptions are not valid. We described syntaxa: Eryngio falcati-Securigerion securidacae all. nova, Ajugo chiae-Lactucetum serriolae ass. nova, Phlomido grandiflorae-Cistetum salvifolii ass. nova, and Arbuto andrachnes- Quercetum cocciferae ass. nova and selected nomenclatural type for Querco- Phillyreetum mediae Barbero & Quézel 1976.
First record of Aphis craccivora Koch (Hemiptera: Aphididae) on aronia crop in Montenegro
Authors: Latinović N. , Karamaouna F. , Kavallieratos N.G.
Published: July 2017

The aphid Aphis craccivora was recorded on the crop of aronia, Aronia melanocarpa, in Montenegro, in June 2015 and 2016. This is the first record of A. craccivora in Montenegro on aronia.
Reaction of the native Greek tomato varieties ‘Chondrokatsari Messinias’ and ‘Katsari Santorinis’ to Fusarium oxysporum f. sp. lycopersici and Rhizoctonia solani infection
Authors: Darras A.I. , Kotsiras A. , Delis C. , Nifakos K. , Pavlakos E. , Demopoulos V.
Published: July 2017

Plants have to cope with a number of biotic stresses among which, infectious diseases. The present study was conducted to investigate the reaction of two native Greek tomato vars, ‘Chondrokatsari Messinias’ and ‘Katsari Santorinis’, to infection by Fusarium oxysporum f. sp. lycopersici and Rhizoctonia solani. Disease symptoms, disease incidence and severity were recorded and the effects of infection on the number of flowers, the biomass production (fresh and dry weight), CO2 assimilation, stomatal conductance and transpiration were also evaluated. Both tomato varieties were susceptible to F. oxysporum f. sp. lycopersici and R. solani infection. However, ‘Chondrokatsari Messinias’ was found to be less susceptible to F. oxysporum f. sp. lycopersici compared to ‘Katsari Santorinis’. Both pathogens negatively affected biomass production of var. ‘Chondrokatsari Messinias’ but not that of ‘Katsari Santorinis’. The number of fl owers produced by ‘Chondrokatsari Messinias’ was negatively affected by R. solani but not by F. oxysporum f. sp. lycopersici. Infection of both varieties by R. solani also caused reduction in the CO2 assimilation, stomatal conductance and transpiration.
Issues in Using Self-Organizing Maps in Human Movement and Sport Science
Authors: Serrien B. , Goossens M. , Baeyens J-P.
Published: July 2017

Self-Organizing Maps (SOMs) are steadily more integrated as data-analysis tools in human movement and sport science. One of the issues limiting researchers’ confidence in their applications and conclusions concerns the (arbitrary) selection of training parameters, their effect on the quality of the SOM and the sensitivity of any subsequent analyses. In this paper, we demonstrate how quality and sensitivity may be examined to increase the validity of SOM-based data-analysis. For this purpose, we use two related data sets where the research question concerns coordination variability in a volleyball spike. SOMs are an attractive tool for analysing this problem because of their ability to reduce the highdimensional time series to a two-dimensional problem while preserving the topological, non-linear relations in the original data. In a first step, we systematically search the SOM parameter space for a set of options that produces significantly lower continuity, accuracy and combined map errors and we discuss the sensitivity of SOM-based analyses of coordination variability to changes in training parameters. In a second step, we further investigate the effect of using different numbers of trials and variables on the SOM quality and sensitivity. These sensitivity analyses are able to validate the conclusions from statistical tests. Using this type of analysis can guide researchers to select SOM parameters that optimally represent their data and to examine how they affect the subsequent analyses. This may also enforce confidence in any conclusions that are drawn from studies using SOMs and enhance their integration in human movement and sport science.
Dependence of spectral characteristics on parameters describing CO2 exchange between crop species and the atmosphere
Authors: Uździcka Bogna , Stróżecki Marcin , Urbaniak Marek , Juszczak Radosław
Published: July 2017

The aim of this paper is to demonstrate that spectral vegetation indices are good indicators of parameters describing the intensity of CO2exchange between crops and the atmosphere. Measurements were conducted over 2011-2013 on plots of an experimental arable station on winter wheat, winter rye, spring barley, and potatoes. CO2fluxes were measured using the dynamic closed chamber system, while spectral vegetation indices were determined using SKYE multispectral sensors. Based on spectral data collected in 2011 and 2013, various models to estimate net ecosystem productivity and gross ecosystem productivity were developed. These models were then verified based on data collected in 2012. The R2for the best model based on spectral data ranged from 0.71 to 0.83 and from 0.78 to 0.92, for net ecosystem productivity and gross ecosystem productivity, respectively. Such high R2values indicate the utility of spectral vegetation indices in estimating CO2fluxes of crops. The effects of the soil background turned out to be an important factor decreasing the accuracy of the tested models.
Physical and antioxidant properties of gluten-free bread enriched with carob fibre
Authors: Różyło Renata , Dziki Dariusz , Gawlik-Dziki Urszula , Biernacka Beata , Wójcik Monika , Ziemichód Alicja
Published: July 2017

There are no reports of addition of carob fibre to gluten-free bread, as only carob germ flour was used. The research task was to determine what level of carob fibre can be used and how it influences the physical and sensorial properties of gluten-free bread. Especially, the knowledge of the antioxidant properties of such bread is very valuable. The gluten-free bread from rice, corn, and buckwheat flour (35:35:30%) was prepared after mixing (5 min), proofing (40 min, 30°C), and baking (45-50 min, 230°C) of dough. Carob fibre was added in the amounts of 1, 2, 3, 4, and 5% of the total flour content. The results showed that increased content of carob fibre induced significant and favourable changes in the volume, colour, and texture (hardness and springiness) of the bread crumb. Carob fibre enriched the breads with lipophilic compounds able to chelate metal ions. The activity of hydrophilic compounds was significantly higher in the case of control bread and bread with the lowest percentage of the additive. In conclusion, the highest increase in antioxidant activity was found for breads with 1 and 2% of carob fibre. The most acceptable gluten-free bread can be obtained by adding up to 2% of carob.
Viscoelastic properties of tablets from Osborne fractions, pentosans, flour and bread evaluated by creep tests
Authors: Escalante-Aburto Anayansi , de Dios Figueroa-Cárdenas Juan , Véles-Medina José Juan , Ponce-García Néstor , Hernández-Estrada Zorba Josué , Rayas-Duarte Patricia , Simsek Senay
Published: July 2017

Little attention has been given to the influence of non-gluten components on the viscoelastic properties of wheat flour dough, bread making process and their products. The aim of this study was to evaluate by creep tests the viscoelastic properties of tablets manufactured from Osborne solubility fractions (globulins, gliadins, glutenins, albumins and residue), pentosans, flour and bread. Hard and soft wheat cultivars were used to prepare the reconstituted tablets. Sintered tablets (except flour and bread) showed similar values to those obtained from the sum of the regression coefficients of the fractions. Gliadins and albumins accounted for about 54% of the total elasticity. Gliadins contributed with almost half of the total viscosity (45.7%), and showed the highest value for the viscosity coefficient of the viscous element. When the effect of dilution was evaluated, the residue showed the highest instantaneous elastic modulus (788.2 MPa). Retardation times of the first element (λ1~ 3.5 s) were about 10 times lower than the second element (λ2~ 39.3 s). The analysis of compliance of data corrected by protein content in flour showed that the residue fraction presented the highest values. An important contribution of non-gluten components (starch, albumins and globulins) on the viscoelastic performance of sintered tablets from Osborne fractions, flour and bread was found.