bluuebunny/crossref_metadata_2025_split huggingface dataset:
Perturbation of Electromagnetic Radiation of Downlink in Orthogonal Components on the GOES 16 Satellite by Planar Antenna Phase Array
Authors: Heilmann A , Tertuliano Filho H. , Dartora C. A. , Clistenes D. , Adams A. M. 
Published: November 2019

Abstract
The Geostationary Operational Environmental Satellite - GOES 16 has an arrangement of planar antennas for uplink and downlink communications in the L-band range, UHF frequency (1694,3/1694,9 MHz), 16 W transmission power and a planar antenna array gain of 28 dBi, for communication operations and data scanning. The structure of antennas in the form of arrangement combines high directivity in the electromagnetic signal and reduction of the broadside, which corresponds to a smaller angular variation. Assuming a communication channel for the GOES 16, from the phase arrangement of planar antennas using 4 rectangular radiant elements of 30 cm × 30 cm (patch) in the transmission (downlink), we defined an expression for the gain of the array of planar antennas and model an acceleration for the satellite, due to the effect of the electromagnetic perturbation it admits, antenna theory and the energy-momentum conservation laws. For a state vector - 04/02/2019, at 18h 40m 12.44s, we implemented a routine using numerical methods with the equation of movement in the form of Cartesian components, which can be used for both keplerian movement as well as adding the desired disturbing accelerations. We propagate its orbit over a period of 5 days, with a step of 10 minutes, and correlate the results of this propagation in the propagated orbital model without disturbance and with the disturbance of the acceleration on the satellite of electromagnetic origin, centered in the phase arrangement of flat antennas. The perturbative effect of this model is applied on GOES 16 taking into account satellite mass, antenna characteristics, radiated power and maximum antenna gain. The numerical integrator used for the solution of the satellite motion equation is based on the fourth and fifth degree Runge-Kutta method, and the results shows that the phase arrangement of planar antennas with the described configuration implies a significant electromagnetic disturbance, changing the components in the direction (radial, transverse and normal) and the coordinates XYZ.
Particle-in-cell numerical simulation of the PHall-IIc Hall thruster
Authors: Braga Leonardo L. , Miranda Rodrigo A. 
Published: November 2019

Abstract
In this work we compare the performance of two types of Hall thrusters, namely, the SPT-100 and the PHall-IIc, the latter being developed by the Plasma Physics Laboratory at the University of Brasilia. The comparison is carried out by performing particle-in-cell simulations. We compute thruster parameters such as thrust and specific impulse. Our results can contribute to the design of electric propulsion devices for future Brazilian space missions.
Orbital maneuvers to form a constellation of small satellites from a single large spacecraft
Authors: Cavalca M P O , Prado A F B A , Gomes V M , Sanchez D M 
Published: November 2019

Abstract
The main goal of the present paper is to show how to form a constellation of small satellites when all small satellites leave from a larger spacecraft. It is assumed that they will all stay in a planar formation, in the same orbital plane of the mother spacecraft, just dispersed in terms of mean anomaly. Initially, it is considered that the larger satellite orbits the Earth in an almost circular orbit with 2000 km of altitude. Then, a search for initial conditions of the small satellite is performed to find the best ones to move it away from the larger satellite such that it is allocated in a co-orbital orbit with respect to the larger satellite. These initial conditions should minimize the consumption of an impulsive maneuver required to move away the small satellite from the large one to put it in course to its final orbit, trying to make the best use of the most relevant perturbations, such as the solar radiation pressure and the oblateness of the Earth. In a second study, we will analyze the influence of the solar radiation pressure, depending on the A/m ratio of the spacecraft, in the trajectories.
Parametric study of polar configurations around binaries
Authors: Giuppone C. A. , Cuello N. 
Published: November 2019

Abstract
Dynamical studies suggest that most of the circumbinary discs (CBDs) should be coplanar. However, under certain initial conditions, the CBD can evolve toward polar orientation. Here we extend the parametric study of polar configurations around detached close-in binaries through N-body simulations. For polar configurations around binaries with mass ratios q below 0.7, the nominal location of the mean motion resonance (MMR) 1 : 4 predicts the limit of stability for eB > 0.1. Alternatively, for eB < 0.1 or q ∼ 1, the nominal location of the MMR 1 : 3 is the closest stable region. The presence of a giant planet increases the region of forbidden polar configurations around low mass ratio binaries with eccentricities eB∼ 0.4 with respect to rocky earth-like planets. For equal mass stars, the eccentricity excitation Δβ of polar orbits smoothly increases with decreasing distance to the binary. For q < 1, Δβ can reach values as high as 0.4. Finally, we studied polar configurations around HD 98800BaBb and show that the region of stability is strongly affected by the relative positions of the nodes. The most stable configurations in the system correspond to polar particles, which are not expected to survive on longer time-scales due to the presence of the external perturber HD 98800AaAb.
Adhesive-free joining and application for flexible devices - a review
Authors: Taga Yasunori , Nishimura Keisuke , Hisamatsu Yuri 
Published: November 2019

Abstract
Interface has been recognized for a long time as a part of materials such as surface and grain boundary in bulk in spite of the fact that interface gives decisive influences on the performance and durability of devices in practical use. Interface is also well known to have four principal performances and roles such as mechanical, electrical, magnetic and optical properties. Here, I will at first review the interface behavior with special emphasis on materials science and then introduce typical examples of case study. Mechanical behavior of interface can be attributed to joining of different materials in particularly at low temperature and intrinsic defects introduced in the process of joining caused by difference in thermal expansion. Defects thus introduced is known to result in work hardening of interface. Recently, an epoch-making method of joining to utilize water gas adsorption layer as an adhesive agent. This gas adsorption joining (GAJ) was demonstrated in cycloolefin polymer (COP) film and borosilicate glass system. Both surfaces were first modified by atmospheric pressure plasma, followed by close lamination to reaction distance and heated at about 100°C to result in the formation of a strong covalent bond for joining. Durability thus formed system was found to remain unchanged even after weathering test in 60°C, 95%RH for 2000 hrs. Joining mechanism can be explained in terms of an increase in density of functional molecules at the interface, followed by dehydration. Thickness of joining layer was confirmed by X-ray photoelectron spectroscopy and STEM and EELS to be 1∼2nm. Sealing performance of GAJ was examined by measuring Water Vapor Transmission Rate (WVTR) by MOCON system using joined PET films on which high barrier layer was coated. The WVTR of line sealing with 1 mm width and 1-2 nm thick was found to be better than 5 x 10−4 g/m2/day. Practical applications of thus developed GAJ for joining and sealing are now in progress for flexible film devices such as OLED display, solar cells, and healthcare devices. Finally, roles of interface in materials science in future will be critically discussed.
Texture and structure formation of low-carbon low-alloy pipe steel after TMCP and heat treatment
Authors: Danilov Sergey , Semkina Iana , Pyshmintsev Igor , Lobanov Mikhail 
Published: November 2019

Abstract
The structure and texture of low-carbon low-alloy pipe steel after Thermo-Mechanical Controlled Processing (TMCP) and subsequent isothermal quenching were studied by the method of Electron Backscatter Diffraction (EBSD) analysis. The texture, obtained after TMCP, was formed mainly by two strong scattered orientations from {112}<110> and two weaker scattered orientations from {110}<223> and one weak orientation (001)[110]. Complex multicomponent textures were observed after heat treatment. The regions with “ferrite” and martensitic structures were identified and analyzed using Oxford Instruments HKL software. Orientations, constituting textures for both selected areas types, are associated with the basic orientations of the initial deformed austenite grains, formed during the hot deformation by orientation relationships (OR), transitory between Kurdjumov-Sachs OR and Nishiyami-Wasserman OR.
Engineered composite polymer sheets with enhanced thermal conductivity
Authors: Der Oguzhan , Edwardson Stuart , Marengo Marco , Bertola Volfango 
Published: November 2019

Abstract
An innovative type of engineered composite polymer sheet with enhanced thermal conductivity is described and tested. The concept is to sandwich a closed-loop serpentine channel, cut out in a polypropylene sheet and containing a self-propelled liquid-vapour mixture, between two sheets of the same material bonded by selective laser welding. Polymer materials are widely used to replace metals in different applications, however sometimes this is not possible because of their poor thermal conductivity. Thin, flexible and low-weight polymer sheets can be advantageous in various aerospace, aircraft and portable electronic applications where the device weight and its mechanical flexibility are crucial. The transient and steady-state thermal response of a prototype engineered polymer sheet was characterised for different heat power levels and spatial orientations. The equivalent thermal conductance, calculated from the surface temperatures at opposite ends of the sheet, increases four to six times in comparison with a composite polypropylene sheet without working fluid.
Elastic, Electronic, and Optical properties of NaSnX (X=Sb, Bi, As): First principle calculations
Authors: Koc Husnu , Mamedov Amirullah M , Ozbay Ekmel 
Published: November 2019

Abstract
In the present work, the structural, mechanical, electronic and optical properties of NaSnX (X=Sb, B, As) compounds have been investigated by means of first principles calculations. The generalized gradient approximation has been used for modeling the exchange-correlation effects. It has been observed that the calculated lattice parameters are in good agreement with the experimental and theoretical lattice parameters. Bulk modulus, shear modulus, Young’s modulus Poisson’s ratio, sound velocities and the Debye temperatures using the calculated elastic constants for NaSnSb, NaSnBi and NaSnAs compounds have been obtained. The electronic band structure and the projected density of states corresponding to the electronic band structure have calculated.and interpreted. The obtained electronic band structure for NaSnSb and NaSnBi compounds are metallic in nature, and the NaSnAs compound is also a narrow semiconductor. Based on the obtained electronic structures, we further calculated the frequency-dependent dielectric function, the energy-loss function, optical conductivity, and reflection along the x-and z-axes.
The Diagnostics of Optical and Thermal Characteristics of Semitransparent Media at Modeling Phase Influence of Oscillating Convection and Thermoradiation
Authors: Zagumennov Fedor A. , Merzlikin Vladimir G. , Bystrov Andrey V. 
Published: November 2019

Abstract
The paper suggests diagnostics method of non-stationary combined regime heating of semitransparent materials base on an evaluation of the interconnected complex of optical parameters (extinction – brad
, scattering-σ and absorption κ indices) and thermophysical (thermal diffusivity aT
and conductivity coefs) ones using simulation the general temperature field

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including the additive terms due to the convective and radiation fluxes with a phase shift

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within the external oscillating (frequency ω ) heat load.A one-dimensional problem of finding the temperature for a semitransparent material in the absence of aggregative transitions, neglecting long wavelength re-emission was considered in the analytic representation. The classical solution (of the homogeneous heat equation) and the particular one (of the inhomogeneous one with an internal thermal radiant source) defined summable terms with independent phases

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simultaneously with external convection impact on the exposed surface allowed for the first time to establish interconnected complex

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The obtained formulas for specific temperature distributions allow you to use them to estimate values of optical and thermal parameters of a semitransparent material from experimentally recorded phase jumps of the temperature field during the action of alternate impact of initial phased convective and radiation components of the external heat flux. The results of the study can be used both for experimental diagnostics and to select the heat regimes for combined radial and convective processing of semitransparent ceramics, composites, and biomaterials.
Effect of composition and heat treatment on porosity and microstructures of technical ceramics made from kaolin and IG-017 additive
Authors: Kurovics Emese , Gömze László A. , Ibrahim Jamal Eldin F. M. , Gömze Ludmila N. 
Published: November 2019

AbstractBased on conventional kaolinite and IG-017 bio-original additives of IGREX Ltd. the authors have developed new ceramic composite materials for different industrial purposes. In this work, different powder mixtures of kaolinite and IG-017 bio-original additive were milled and uniaxially pressed at different compaction pressures into cylindrical discs, after compaction, the discs were sintered in electric kiln under oxidation atmosphere and in oxygen-free atmosphere. Using the oxygen-free sintering process, new high porosity ceramic materials were created. Through the examination of the microstructure of the produced specimens the authors have found that the ceramic structure is reinforced with carbon nanofibers.
Computer Modeling of the Stress-Strain State of the Cervical Spine Segment
Authors: Rikun Yu A , Сhaikovskaya(Kolmakova) T V , Kulkov S N 
Published: November 2019

Abstract
The article presents the results of the calculation of the stress-strain state of the C3-C4 segment of the cervical spine at flexion forward. The results of the calculations showed that there is the change in the deformation behavior of the segment and the change in the localization areas of the largest tensile and compression stresses at the increase in the elastic modulus of the intervertebral disk.
Unique microstructural and mechanical properties of Al-Zn alloys processed by high-pressure torsion
Authors: Chinh Nguyen Q. , Kovács Zsolt 
Published: November 2019

Abstract
Al-Zn alloys with different Zn concentrations between 2 and 30 wt.% were processed by high-pressure torsion (HPT) to produce ultrafine-grained (UFG) materials. Microstructural and mechanical and properties of these UFG alloys were then investigated using depth-sensing indentations (DSI), focused ion beam (FIB), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). Emphasis was placed on the decomposition due to the HPT process, as well as on its effects on the mechanical properties of the UFG alloys. For low Zn contents, HPT gave strengthening due to grain refinement while for the highest Zn concentration the decomposition of the microstructure yielded an abnormal softening at room temperature. The microstructure decomposition led also to the formation of a Zn-rich phase, which wets the Al/Al grain boundaries and enhanced the role of grain boundary sliding with unusually high strain rate sensitivity. The occurrence of intensive sliding in these UFG alloys at room temperature is demonstrated by deforming micro-pillars, illustrating a potential for the effective application of these UFG materials in micro-devices
Corrosion of glass used for radioactive waste disposal influenced by iron corrosion products
Authors: Dabbas Ali AL , Kopecskó Katalin 
Published: November 2019

Abstract
Iron corrosion products of the steel canister in the nuclear waste container are highly silica sorptive materials and very much expected to delay formation of the protective layer (gel) on the nuclear glass interface. This study is focusing on the role of the iron carbonates (ankerite), which is probably one of iron corrosion products and already exists in the clay structure of the disposal depth. Simulating nuclear borosilicate glass samples (alternative to the R7T7-type) samples are planned to leach in different series of experimental models with dissimilar quantities of ankerite. Batch experiments all will be cultivated in synthetic groundwater; where different pH (4-9) values and temperatures (35, 50, 90 °C) are considered. In this paper the state of the art of the radioactive waste glass corrosion in the circumstances of deep geological disposal will focus on the role of ankerite as one of the iron corrosion products and clarify how it is expected to show delay in achieving the Si saturation status and accelerate glass alterations.
Time evolution of ZnO-CNT photoluminescence under variable ambient and temperature conditions
Authors: Rauwel P , Galeckas A , Rauwel E 
Published: November 2019

Abstract
ZnO-CNT hybrid materials were prepared by non-aqueous sol-gel routes at 240ºC. The morphology and defects have been studied by transmission electron microscopy and photoluminescence spectroscopy. The hybrid nanostructures manifest a broad luminescence emission covering the visible spectrum. Variations in photoluminescence with time are observed for the ZnO-CNT hybrid structures exposed to different ambient and temperatures. The studies show that photoluminescence from adsorbed oxygen dominates the emission emanating from other intrinsic defects and also affects the stability of the latter over time.
Formation of iron sulfide photocatalytic colloidal dispersion via pulsed laser ablation in liquids
Authors: Vála Lukáš , Vavruňková Veronika , Jandová Věra , Pola Michal , Křenek Tomáš 
Published: November 2019

Abstract
Pulsed laser irradiation of iron sulfide in water and ethanol allows laser ablation and generation of FeS nano/micro particles. Measurement of the size distribution reveals 100, 1000 and 5000 nm sized particles in water and 180 nm sized particles in ethanol. The values of zeta potential: 13.2 mV for colloid in water confirm incipient stability and tendency for coagulation whereas the value: -40.6 mV shows good stability of ablatively achieved nanoparticles in ethanol. SEM analyses of particles obtained by evaporation of solvents on Ta substrate revealed shapeless, roundshape and sheet-like morphology of agglomerates whose size span from units up to tens of µm. Also spherical particles sized around tens of nm were detected. EDX shows Fe/S ratio ∼3.25 and ∼ 1.2 for particles ablated in water and ethanol respectively. Raman spectroscopy indicates the formation of mackinawite (Fe1+xS) and pyrrhotite (Fe1-xS) phase. The photocatalytic effect of prepared water colloid was tested in methylene blue (MB) degradation under the daylight.
The Effect of Heat Input Parameters on Residual Stress Distribution by Numerical Simulation
Authors: Hasan Alhafadhi Mahmood , Krallics Gyorgy 
Published: November 2019

Abstract
This paper deals with Numerical Simulation to analyze the behavior of residual stresses in the plate. The residual stresses at the surface of some weld specimen by using the finite element technique. The results of the numerical simulation analysis were compared with three cases data to evaluate the accuracy of Goldak model (double ellipsoidal heat distribution model). Based on this study, a modeling procedure with reasonable accuracy was investigated. The developed finite element modeling was used to investigate the effects of welding heat input on magnitude and distribution of welding residual stresses in a welded plate made of steel. The different directions of residual stresses in the surface of the plate of 25 mm thick for V-groove shape were studied. It is shown that the welding heat input parameters have a significant effect on the magnitude and distribution of residual stresses.
Local mechanical properties of advanced skutterudites processed by various routes
Authors: Buršík Jirí , Buršíková Vilma , Rogl Gerda , Rogl Peter 
Published: November 2019

Abstract
Skutterudites are an important class of thermoelectric p- and n-type materials and they have already achieved fair efficiencies for the conversion of heat to electricity. Nevertheless researchers try to further enhance the figure of merit, ZT, by various ways. In this work we compare the microstructure and mechanical properties of an industrial p-type DDyFe3CoSb12 skutterudite powder processed by several routes containing various combinations of ball milling, hot pressing, cold pressing and high pressure torsion. Details of the resulting microstructure are studied by means of analytical electron microscopy as well as by means of local mechanical testing.
The effect of the synthetic fibre reinforcement on the fracture energy of the concrete
Authors: Juhász K P 
Published: November 2019

Abstract
Fibre reinforced concrete belongs to the group of composite materials, where matrix means the concrete, and fibres mean the various shaped (straight, hooked, wavy, etc.) and material (steel, polypropylene, glass, etc.) fibres, which are short compared to the size of concrete elements. Fibres are mixed in fresh concrete which supposedly provides a perfect and uniform mix. Although material of the fibres can be different (steel and synthetic polypropylene are the most widespread), material models in literature are primarily for steel fibres. Elastic modulus of steel and synthetic fibres differs from each other in terms of scale (steel 210 GPa, synthetic 8-12 GPa), despite this, however, similar results are received frequently at bending beam tests. The different result lies in the energy absorption of the fibres pulling out from the concrete matrix. In the present paper, this different behaviour is examined and a suggested material model for fibre reinforced concrete is presented. This material model is based on the modification of the fracture energy.
Synthesis and Powder Properties of Cerium Phosphate White Pigments
Authors: Onoda Hiroaki , Muraki Haruka 
Published: November 2019

Abstract
Catalytically active cerium dioxide is used as light reflection materials for cosmetic applications. Herein, as novel white pigments for use in cosmetics, cerium phosphates were prepared under various conditions. The chemical composition, powder properties, photocatalytic and oxidation catalytic activities, color phase, and smoothness of the cerium phosphates were evaluated. Samples prepared from cerium (+III) nitrate solution indicated XRD pattern of cerium phosphate hydrate. All samples prepared in this work had large particles and no specified shape. The obtained cerium phosphates exhibit little photocatalytic activity and no oxidation catalytic activity. These samples exhibit a little low reflectance within the range of visible light and 71-78 in L* value.