bluuebunny/crossref_metadata_2025_split huggingface dataset:
Morphological changes of the PVD coatings after isothermal annealing
Authors: Babincová P , Sahul M , Drobný P , Čaplovič Ľ 
Published: January 2020

Abstract
The main of this work is to investigate the impact of the isothermal annealing on the structure and morphological changes on the PVD hard coatings. Three different coatings based on the AlTiN system were deposited onto cemented carbide substrates containing 6 wt% of Co. Two coatings AlTiN/TiAlN and AlTiN/TiN with an initial thickness of 3 μm has a coarse-grained columnar structure with a chemically graded nanomultilayering consisting of alternating Ti-rich and Al-rich layers. In the case of the AlTiN/TiAlN coating, a total of 20 layers were applied. Ten layers had a thickness of 200 nm (AlTiN) and 10 layers with the thickness of 100 nm (TiAlN). The same number of nanolayers was also retained for the AlTiN/TiN multilayer coating. The TiN layers were 100 nm thick. The third coating was a nanocomposite sandwich coating formed by a TiSiN adhesive layer (50nm), a functional nanocomposite AlTiSiN layer (2 μm) and a top functional TiSiN layer with a thickness of 1 μm. The coatings were prepared by cathodic arc evaporation using the LARC® technology. After deposition, the samples were annealed at high temperatures (700 °C, 800 °C, 900 °C, 1000 °C) for one hour in air. With X-ray diffraction and scanning electron microscopy, the morphology, structure and phase composition of coatings and oxide layers after annealing were evaluated.
After the heat-treatment at 800 °C, cross-sectional and surface morphology images revealed, that an oxide layer has grown on top of the all coatings. EDS analysis showed that the oxide layers on the multilayers coatings had a layered structure, which was found to be the consequence of the high diffusion rate of Al. The interface with the coatings was very rough. It was depleted of Al, which diffused to the upper surface of the oxide. The oxidation process of nanocomposite AlTiSiN/TiSiN coating started by forming an oxide layer of ternary Ti–Si–O at the interface. This system segregated into two phases of TiO2 and SiO2. The nanocomposite coating remained stable even after annealing at 1000 °C. The surface of the multilayers was accompanied by a network of cracks at this temperature. An interesting phenomenon was also observed on the substrates itself during the annealing. As a result of oxidation, unprotected sides of the substrates expanded. Globular oxides based on tungsten and cobalt were also formed on the surface of the samples at the places where the coating was peeled off. The reasons for the differences are discussed.
Acoustic emission analysis of hard coatings cracking during indentation test
Authors: Drobný P , Čaplovič Ľ , Sahul M , Babincová P , Koula V 
Published: January 2020

Abstract
Hard coatings are widely used in industries where the good behaviours of surface properties play the main role in a life cycle of machine components. The main material characteristic of coatings which determines behaviour of surface is Hardness. In the past, Hardness of materials was considered to be the most important material property, which influences wear properties of coatings as well as value of maximal elastic tension needed for initiation of cracks. However, Adhesion of hard coatings depends on mechanical properties such as Young modulus E, hardness H and fracture toughness R. Initiation/Formation of fractures and their propagation in hard coatings is commonly investigated using indentation tests. Creation of Hard coating crack during indentation is usually detected as a wide frequency AE signal. In this article, the initiation of cracks is investigated using data measured during the indentation. The cracks formation/propagation and spalling in hard coatings during indentation were observed and quantified by using AE. AE frequency analysis was calculated from the signals measured during the indentation and it was evaluated from recorded AE signals.
On the problem of processing data from a cross-sectional image of grained structure
Authors: Minárik S , Martinkovic M 
Published: January 2020

Abstract
The anisotropy of a grained structure is a consequence of non-uniform distribution of spatial orientation of grains. Conventional stereological methods allow determine spatial distribution of grain orientation from lines distribution observed on structure cross sections. The distribution of grain’s surface orientation in space is determined by measuring the total length of cross sections on a cutting plane. In this paper, we indicate partial but significant problem of stereology. A rectangular model of grained structure is considered. Then the kernel function, which connects the probability density function (distribution) of lengths of rectangles intersections visible on observation planes with size of rectangles sides, is calculated.
Deposition and characterization of Ti-Al-C-N coatings
Authors: Sahul M , Haršáni M , Babincová P , Čaplovič L’ , Sahul M , Drobný P 
Published: January 2020

Abstract
In the present work, Ti-Al-C-N coatings were deposited on cemented carbide substrates by lateral rotating cathodes (LARC®) process using Platit π80+DLC deposition unit. The effect of C2H2 gas flow rate on elemental and phase composition, deposition rate, cross-sectional and surface morphology, mechanical and tribological properties of the coatings was studied. Following analytical techniques, namely: scanning electron microscopy (SEM) with energy and wave dispersive X-ray spectroscopy (EDS and WDS), X-ray diffraction analysis (XRD), nanoindentation measurements, Rockwell C indentation test and tribological testing were used for Ti-Al-C-N coatings evaluation. From the EDS analysis, it was found that the carbon content in the coatings increased from 0 at.% to 22.3 at.% as the C2H2 gas flow rate increased from 0 sccm to 75 sccm. The increase in deposition rate of coatings from 0.029 μm/min to 0.052 μm/min was documented. From XRD results it was found that the coatings consist of a cubic B1-NaCl type Ti1N0.9 phase. The maximum hardness was observed at C2H2 gas flow rate of 25 sccm and the lowest friction coefficient (0.35) at the maximum C2H2 gas flow rate. The coatings deposited at C2H2 gas flow rates (25 sccm and 50 sccm) exhibited an excellent adhesion.
Impact of phase composition on quality of ASN fertilizers
Authors: Štrbová Z , Jorík V , Kučera M 
Published: January 2020

Abstract
Ammonium Sulfate Nitrate (ASN) based fertilizers are very efficient fertilizers in modern agriculture. Designed to provide targeted nutrition and high yields, they combine the extended availability of Ammoniacal (NH4) and rapid effect of Nitrate Nitrogen (NO3) with the multiple agricultural benefits of Sulfur. Most of these products have some tendency to form agglomerates (caking) and dust during storage in a bulk of hundreds to thousands of tons. The severity of quality deterioration can be influenced by a number of factors, such as phase composition, moisture content, particle structure, mechanical strength, hygroscopic properties, product temperature, ambient conditions, storage time and pressure. ASN fertilizer is mainly a combination of the double salts 3AN·AS ((NH4)5(NO3)3SO4) and 2AN·AS ((NH4)4(NO3)2SO4). It is known that presence of these mixed salts has a strong impact on the quality of fertilizer. Seeing that X-ray Powder Diffraction analysis (XRPD) is commonly used to control the quality of industrially produced fertilizers, a new X-ray method has been developed. This new method is based on the determination of the ratio of the integral intensities of the diffraction lines of the 3AN·AS and 2AN·AS components. The ratio obtained by line profile analysis provides an effective screening test of the quality of fertilizer immediately after production. In accordance with ratio value it is possible to estimate quality changes of product during long-term storage.
Fatigue life of thermoset composite materials
Authors: Zaludek M , Rusnakova S , Kubisova M , Bilek O , Karvanis K 
Published: January 2020

Abstract
This article deals with the lifetime of laminated materials produced by different production technologies (hand lamination technology, vacuum bagging technology and prepreg technology with curing in the oven) during cyclic repeated bending stress. Like tested materials composite systems were chosen composite systems with epoxy matrix and carbon reinforcement (Kordcarbon CC200T, epoxy resin with trade name L285) and second composite epoxy system with glass reinforcement (Quadra-axial glass fabric, named Saertex Q-E-820, epoxy resin Biresin CR 82 and third prepreg systems (unidirectional prepreg, trade name Deltapreg VV430U-DT860W-39% and prepreg system with glass fabric VV320P_DT806R-37%). Fatigue tests were performed by cyclic bending loads during a three-point arrangement on a universal servo-hydraulic testing machine INSTRON 8871. Experimentally the number of cycles fracture of the material was determined at 90 % and 80 % of the maximum breaking load.
Influence of microstructure on fracture feature of Ti6Al4V alloy prepared by 3D printing
Authors: Losertová M , Kubeš V , Drápala J , Dostálová K , Sevostyanov M A , Di Cocco V , Iacoviello F 
Published: January 2020

Abstract
In this work, the Ti6Al4V specimens produced by selective laser melting were mechanically tested in non-heat treated condition and fracture surface features were compared with this one of the material prepared using conventional casting and forging. The results of the fractography observation for both types of the samples were explained on the base of the microstructure analysis. The fracture surface of selective laser melted specimens showed more brittle feature that was in relation with the microstructure composed almost fully of martensite as opposed to conventionally prepared alloy with bimodal (α + β) microstructure and more ductile character of fracture surfaces.
Structure and Properties of SWCNT-Modified CFRP
Authors: Burkov M V , Eremin A V 
Published: January 2020

Abstract
Structure and mechanical properties of CFRP modified by SWCNT with different content (0.1, 0.2 and 0.3 wt. %) have been studied in the present paper. The structural investigations include SEM imaging while the mechanical properties have been characterized via tensile and flexural tests. The main functional feature of such hybrid composite is an electrical conductivity, which has been also measured. Out-of-plane conductivity has been enhanced up to ∼66 S/m from dielectric unmodified CFRP. It has been shown that tensile properties stay almost unchanged, while flexural strength and modulus have increased by 22% and 16% correspondingly.
Application of Laser Welding in Car Bodies Manufacturing
Authors: Viňáš J , Brezinová J , Brezina J , Maruschak P , Panin S 
Published: January 2020

Abstract
The paper deals with a problem of laser welding of zinc-coated steel (DX53D+Z and DX54D+Z) plates. Experiments were carried out with the use of steel plates 0.8; 1.0; 1.3; and 1.75 mm thick. High power 2.5-2.9 kW CO2 laser was employed. CO2 was used as the shielded gas. The optimal parameters of welding for material under study were determined. The mechanical properties of welded joints were measured through the tensile loading and microhardness measurement. Tensile performances of the specimens fabricated at different welding rate and laser beam power were compared with that of the base material.
The Effect of Plastic Deformation on the Geometric Parameters of Nb-Ti-Based Superconducting Cable
Authors: Yntymakova A , Shlyakhova G 
Published: January 2020

Abstract
The current carrying capacity of a superconductor depends on its microstructure, that is, the shape, size and volume content of particles released during the decomposition of a solid solution. At the technological stage, it is necessary to ensure continuity of the process and a given density of micro defects. Therefore, the aim of this work was to assess and present the results of studies of the effect of plastic deformation (tension) on the structure of a multicore superconductor based on Nb-Ti alloy. Mechanical tests were carried out for uniaxial tension to failure on a Walter + Bai AG LFM-125 testing machine (maximum force up to 125 kN). The internal structure of the sample at the fracture site after the sample preparation was studied using a Neophot-21 optical microscope. The effect of deformation on the geometric parameters of Nb-Ti fibers was studied. Sample preparation included thin sections, polishing and etching.
Influence of a Delamination Type Defect on the Operational Life of a Sound-Absorbing Structure with a Honeycomb Filler
Authors: Anoshkin A N , Pisarev P V , Ermakov D A 
Published: January 2020

Abstract
In the framework of this research, the authors proposed an algorithm for predicting the residual life of sound-absorbing structures (SAS) from polymer composite materials (PCM) using the structural-phenomenological model. To assess the residual life of PCM structures under cyclic loading, it was proposed to use the approach of explicit description of the adhesive layer destruction process. The influence of the defect in the form of delamination on the honeycomb filler SAS operational life and stiffness was revealed. The description of the damage accumulation and destruction in the structure processes was obtained for the considered SAS under cyclic loading.
Influence of Heterogeneity Composite Filament for Additive Technology on its Electrophysical Properties at THz Range
Authors: Smygalina P P , Badin A V , Pidotova D A , Trofimov E A 
Published: January 2020

Abstract
In paper the results of a research of the effect of porosity on the dielectric properties of a composite filament for a 3D-printer based on the fused deposition method were presented. The process of creating a composite filaments based on acrylonitrile butadiene styrene and multi-walled carbon nanotubes is described. On a quasi-optical spectrometer, the dielectric permittivity of samples of composite materials 3D printed from a porous filament at a frequency of 210 GHz were obtained.
Quasi-Optical Resonant Single-Frequency Flaw Detector of Polymer Filament for 3D Printing
Authors: Teterina D D , Dorofeev I O , Badin A V 
Published: January 2020

Abstract
In the paper quasi-optical resonant single-frequency flaw detector for investigation of heterogeneity of 3D printer polymer filament are described. A scheme of quasi-optical flaw detector based on 10 GHz open resonator with a filament broaching mechanism is given. Industrial filaments based on polystyrene, polyethylene terephthalate glycol and acrylonitrile styrene acrylate were tested in a flaw detector. The measured amplitudes at the maximum of the resonance curve in the presence of a filament in the inside of the resonator are presented.
The pH Level Influence on Hydroxyapatite Phase Composition Synthesized with Hydrothermal Method
Authors: Chuprunov K , Yudin A , Lysov D , Kolesnikov E , Kuznetsov D , Leybo D , Ilinykh I , Godymchuk A 
Published: January 2020

Abstract
This paper reports the pH level influence on hydroxyapatite phase composition synthesized with hydrothermal method in Ca(OH)2-H3PO4, Ca(NO3)2-(NH4)2HPO4-NH4OH, Ca(OH)2-NH4H2PO4.The obtained samples were studied with X-Ray diffraction, Fourier Transform Infrared (FTIR) and Raman spectroscopy. The one phase Ca5H2O13P3 high crystallinity hydroxyapatite was synthesized with hydrothermal method at pH equal to 11. The crystallinity degree was calculated from the X-Ray diffraction pattern and became 0.96. The increasing pH level from 7 to 11 provides obtaining one phase hydroxyapatite at pH level 11 instead the two phase Ca9.04(PO4)6(OH)1.68, CaHPO4 at pH level 9 and CaPO3(OH), Ca(OH)2 at pH level 7.
Eco-friendly date-seed nanofillers for polyethylene terephthalate composite reinforcement
Authors: Elkhouly Heba I , A Rushdi Muhammad , K Abdel-Magied Ragab 
Published: January 2020

Abstract
Polymer composites have been widely exploited in numerous industries. Micro-particle fillers are typically added as reinforcement materials to improve the characteristics of these composites. In this work, organic nanoparticles of date seeds were added as a filler for polyethylene terephthalate (PET) to produce enhanced polymer nanocomposites. A date-seed nanofiller (DSN) was prepared and examined with x-ray diffraction measurements, and then added to PET by hot compression. The characteristics of the PET-DSN composite were experimentally investigated through tests of mass loss, compressive strength, and Vickers micro-hardness. The PET-DSN microstructure was inspected using a scanning electron microscope and Fourier-transform infrared spectroscopy. The results show chemical stability of the PET-DSN composite. Moreover, key mechanical properties of the composite, namely hardness, compressive strength and wear resistance, were improved and optimized with a DSN reinforcement of 0.75 wt%.
Preparation and high-temperature wear behavior of NiAl-Ti3AlC2 fabricated by thermal explosion
Authors: Yuan Jianjun , Wang Qingzhao , Liu Xinying , Lou Shumei , Li Qun 
Published: January 2020

Abstracts
In this paper, a novel NiAl-based composite reinforced with different content Ti3AlC2 particles was fabricated by thermal explosion using Ni, Al, and Ti3AlC2 powders as starting materials. The microstructure and high-temperature wear behavior of NiAl-Ti3AlC2 composites at 600 °C were investigated. The result showed that increasing Ti3AlC2 content (lower than 15 wt%) could improve the fracture toughness of NiAl-Ti3AlC2, but for the composites with 20 wt%Ti3AlC2 content, the fracture toughness decreased due to low relative density. Wear mechanism of composites was related to the Ti3AlC2 content, the composite with a lower content exhibits oxidation wear, and higher content composite demonstrated both oxidation wear and abrasive wear.
Enhancement thermal stability and CO2 adsorption property of ZIF-8 by pre-modification with polyaniline
Authors: Wang Sheng , Cui Jiaming , Zhang Shengquan , Xie Xianfei , Xia Wenke 
Published: January 2020

Abstract
In this study, the thermal stability and CO2 adsorption property of ZIF-8 were effectively improved by using parallel flow-drop solvothermal method. -NH2 was successfully introduced into the surface of ZIF-8 and their structures by pre-modification with polyaniline. XRD analysis shown that the intensity of ZIF-8 characteristic peak increased with the increase doped content of polyaniline, but the crystal structure of ZIF-8 remained unchanged. FTIR analysis shown that the two new peaks at 1609 and 690 cm−1 can be attributed to the -NH2 bonding of ZIF-8. TGA analysis shown that the thermal stability of NH2-ZIF-8 was 632.71 °C. SEM analysis shown that the increase of CO2 adsorption property was due to the increase of NH2-ZIF-8 cubic crystal system. It was found that BET surface area was 789.7 m2g−1, micropore volume was 0.55 cm3g−1, pore size was 0.99 nm by taking the molar ratio of metal ions to ligands being 1:2, and the molar ratios of polyaniline to metal ions being 12%.
Autologous Costal Cartilage Harvest for Rhinoplasty with Simultaneous Breast Surgery: A Safe and Efficient Technique
Authors: Calvert Jay W , Rovelo Millicent O , Orlando Marc V , Kwon Edwin 
Published: January 2020

Abstract

Background
Autologous costal cartilage is frequently required for revision rhinoplasties and for challenging primary rhinoplasties. Patients undergoing a concomitant breast surgery can have costal cartilage harvested through their breast surgery incisions, thereby obviating an additional rib harvest scar. The safety and efficacy of this approach has yet to be described.

Objectives
The aim of this study was to evaluate the outcomes, safety, and results of a new technique, described here, for harvesting costal cartilage during a concomitant breast operation. Specifically, the rates of capsular contracture and rhinoplasty revisions were of great interest.

Methods
A retrospective review was performed evaluating the senior author’s experience with this technique. Data collected included patient demographics, operations performed, operative time, perioperative morbidity, and postoperative complications. Rates of capsular contracture and rhinoplasty revisions were compared with national averages.

Results
A total of 31 female patients were included. Ten (32.3%) breast complications occurred. There were 6 (19.4%) rhinoplasty complications, comprising 1 infection and 5 revisions. The capsular contracture rate was 6% and the rhinoplasty revision rate was 16%. Both of these rates are comparable to independent breast surgeries and rhinoplasties. There were no cases of perioperative mortality or major morbidity.

Conclusions
Combining breast surgery and rhinoplasty surgery allows for autologous rib harvest through the breast surgery incisions. This is a safe technique that results in outcomes similar to either procedure performed alone. In addition, the patient is spared an additional surgery and donor site scar.

Level of Evidence: 4
Responses to Wildlife Crime in Post-Colonial Times. Who Fares Best?
Authors: Sollund Ragnhild Aslaug , Runhovde Siv Rebekka 
Published: January 2020

AbstractWildlife crime is an increasing problem worldwide. Based on empirical research, we examine how the criminal justice systems of Brazil, Colombia, Uganda and Norway perceive and respond to such crime, with Norway as the main case study and basis for comparison. While the general assumption is that Northern countries are more ‘developed’ in their response to environmental problems, we argue that Norway, despite its economic resources and international profile as a supporter of environmental protection, is failing to confront illegal trade in—and protection of—endangered species nationally. We propose that these Southern countries have developed more tools in terms of legislation, enforcement, awareness and wildlife protection and that Northern countries have expectations regarding conservation in Southern countries that they themselves neglect.
The platform economy: restructuring the space of capitalist accumulation
Authors: Kenney Martin , Zysman John 
Published: January 2020

AbstractThe platform economy and its leading firms, such as Amazon, Facebook and Google, are reorganising the geography of value creation and capture on both a local and global scale. This article argues that economic geographers have underappreciated the implications of the platform on space. First, we demonstrate the concentration of platform giants in terms of location on the US West Coast and in terms of their market share in various services, such as search, maps and online sales. Platforms are simultaneously intermediaries, two-sided markets, data aggregators and leading users of artificial intelligence (AI). Second, we use a labour taxonomy to demonstrate the extensive reach of these platforms in terms of the labour markets that they serve and shape. To illustrate these changes in the geography of value creation, we present case studies of Amazon and Google Maps to show their effects on the location of economic activity. Third, we elaborate on our contention that platforms are at once intermediaries and data hubs. AI is likely to reinforce the power of these platform leaders because they have the largest data sets, the most computational power, enormous teams of the best AI researchers and vast reservoirs of capital that they can use to make acquisitions. We conclude by identifying areas for future research and calling upon economic geographers to consider the implications of the platform economy in reshaping the space of economic activity.