bluuebunny/crossref_metadata_2025 huggingface dataset:
Práticas sustentáveis no desenvolvimento da atividade turística sustentável: Um estudo no Geoparque Seridó - Brasil
Authors: de Lima Francisco Henrique Bezerril
Published: April 2023

The investigation of sustainable practices and actions of the “Geopark Seridó” (GS) emergesin the discussion about sustainability based on the Sustainable Development Goals (SDGs)from the 2030 Agenda of the United Nations (UN). Thus, taking into account that the searchfor such SDGs prevails as a global objective in favor of a better planet for present and futuregenerations, elements and practices on geodiversity emerge, as well as geoparks as a relevantfactor for achieving the 2030 Agenda. This study has the general objective of understandingthe sustainable practices that contribute to the development of sustainable tourism activity ofthe GS, specifically considering: identifying the sustainable practices developed in the GS;analyzing sustainable practices from the perception of GS management, artisans, tour guides,and local drivers; and discussing the sustainable practices of GS in the context of sustainabletourism. The study developed has an interpretive nature, which appears as an exploratoryresearch with a qualitative approach, and a case study as a delineation from a tourist itinerarycarried out in the GS. For data collection, semi-structured interviews, collection of speechesfrom interviews on the internet, and bibliographic research were carried out. That being so,local actors related to the tourist activity of the studied territory were interviewed, as well as arepresentative of the geopark management and tourists. For data processing, the contentanalysis technique was used. As a result of the study, several practices, actions, andeducational activities were identified, which are carried out with the aim of conserving andpreserving the geological heritage of the GS through education and tourism, such as lecturesfor students from public and private schools; training of young guides; macro project;workshops; protection of geosites; wooden structures for tourist access; municipal laws;conceptual maps; mascots; technological applications; courses; training for guides;environmental education signs; educational trails; events; geoproducts; women's association;guides to sensitize tourists; and partnerships with tourism companies. It was found that theseare sustainable practices and actions that aim to involve the community in the sense ofbelonging to the GS, where tourism is related, as well as those practices that insert thecommunity directly with the tourist activity. It was evidenced that the relationship of localactors with tourism is based on environmental education in order to contribute to thesustainable development of the GS territory from the tourist experiences with geoproducts,that said, it contributes to the GS tourist activity being guided by the human development oftourists who experience what the territory offers, facilitating new learning and behaviorchange.
Simultaneous effect of Bacillus thuringiensis B-5351 and salicylic acid on the resistance of potato plants to Phytophthora infestans and yield in the field
Authors: Sorokan A.V. , Burkhanova G.F. , Alekseev V.Yu. , Gordeev A.A. , Mardanshin I.S. , Maksimov I.V.
Published: April 2023

Bacillus thuringiensis are the most common biological insect pest control agents. Some strains of B. thuringiensis are capable of endophytic existence, but the mechanisms of their interaction with plants and the role of phytohormones in this, for example, salicylic acid, which plays a key role in the development of plant immune responses against pathogenic microorganisms, have not been studied. When potato plants were treated with the endophytic strain B. thuringiensis B-5351 and salicylic acid simultaneously, an increase in the number of living bacterial cells in the internal tissues and a more than two-fold reduction in the area affected by late blight on the leaves was observed, relative to the control and action of B. thuringiensis B-5351 separately. The increase in plant resistance was accompanied by the accumulation of transcripts of the gene AY089962encoding the proteinase inhibitor and the activation of its protein product, which was more significant than after individual treatments. Under the field conditions (2020-2021), the treatment of plots with B. thuringiensis B-5351 alone did not reduce the degree of leaf spots infestation, however, in combination with salicylic acid, this indicator decreased by 20-25%. In 2020, the joint treatment of plants led to an increase in the total yield by an average of 20% relative to the control plots, as well as the yield of marketable tubers of the >80 g fraction. In 2021, only the treatment with salicylic acid led to an increase of total yield, but when combined with B. thuringiensis B-5351, the mass of large tubers increased.
High Deposition Efficiency Additive Manufacturing of Titanium Using Low Pressure Nitrogen Cold Spray
Authors: MacDonald D. , Fernández R. , Delloro F. , Jodoin B.
Published: April 2023

In this work, fully dense titanium parts are fabricated by cold gas dynamic spraying (CGDS). Titanium powder is deposited using a low-pressure CGDS process with nitrogen as the carrier gas. The density, porosity, hardness, and tensile properties of the parts produced are determined and discussed.
Particle In-Flight Velocity and Dispersion Measurements at Increasing Particle Feed Rates in Cold Spray
Authors: Meyer M. , Yin S. , Lupoi R.
Published: April 2023

This study investigates cold spray particle velocities achieved at different pressures and particle feed rates using particle image velocimetry (PIV). Particle dispersion and velocity evolution along the jet axis were investigated for several feedstock materials. It was found that average particle velocity decreases with increasing particulate loading. The effect is aggravated at lower pressures, but mainly depends on feedstock material, which implies more complex, volume-fraction related physics playing a role. Velocity distribution and particle dispersion were also found to be influenced by particle feed rate, depending on the material. Increased particle feed rates affect the magnitude and distribution of impact velocity and consequently the efficiency of cold spraying.
Heat-Shock Properties in Yttrium-Oxide Films Synthesized from Metal-Ethylenediamine Tetraacetic Acid Complex Through Flame-Spray Apparatus
Authors: Enkin D. Y. , Komatsu K. , Abe K. , Kosuta T. , Ikeda Y. , Nakamura A. , Ohshio S. , Saitoh H.
Published: April 2023

This study investigates the heat-shock properties of metal-oxide films synthesized from ethylenediamine tetraacetic acid (EDTA) complexes using conventional flame-spray equipment. An EDTA·Y·H powder was placed in the feed unit of the sprayer and transported by a flow of oxygen to the gun. The powder was sprayed using a mixture of H2 and O2 as the flame gas, producing a layer of yttrium oxide on a stainless steel substrate. XRD analysis was used to examine the crystal structure of the deposits and SEM imaging revealed the surface and cross-sectional microstructure. A cyclic thermal shock test was conducted and the deposited film was analyzed for the existence of cracks, deformation, and delamination. Although the number of cracks, crack lengths, and cracks per unit area increased due to heat shock, delaminations were not observed. The results show that the Y2O3 films have high thermal-shock resistance and are suitable for use as thermal barrier coatings.
Coatings Deposited Using a Valve-Less Detonation System
Authors: Bamola R. , Ewell T. , Robinson P. , Gansert R.
Published: April 2023

Although detonation sprayed coatings are harder and better adhered than those achieved by plasma and even HVOF spraying, the method is far less used due to productivity and equipment challenges associated with mechanical valving and intermittent powder flows. This study shows how the use of propane as a fuel eliminates the need for mechanical valving and allows for continuous powder feeding through a high-frequency detonation spray gun. To demonstrate the capabilities of valveless detonation spraying, WC-CoCr powders were deposited under different conditions (oxygen-to-fuel ratio, flow rate, shot frequency) and the resulting coatings were assessed based on porosity, microhardness, deposition efficiency, and phase composition.
Transition Mechanism in Flattening of Plasma Sprayed Ceramic Particles
Authors: Fukumoto M. , Maeda N. , Wie B. , Suzuki D.
Published: April 2023

A transition in the flattening behavior of thermally sprayed metals has been observed in previous studies. It has been proposed that ultra-rapid cooled chill structure preferentially formed at the bottom part of the splat may play a role in the generation of disk-shaped metallic splats. The applicability of this hypothesis to other materials was verified experimentally for several ceramic oxides. To accomplish this, Al2O3, Y2O3, and YSZ particles were plasma sprayed onto stainless steel substrates and the fraction of disk-shaped splats was measured as a function of substrate temperature. Splat microstructure was also examined. Unique amorphous and chill structures were observed in the bottom portion of Al2O3 and Y2O3 splats, indicating that similar formation mechanisms may be at work. However, only a columnar microstructure was observed in the YSZ splats, which calls for additional study.
Warm Spraying of High Strength Ni-Al-Bronze for Cavitation Protection
Authors: Krebs S. , Kuroda S. , Katanoda H. , Gaertner F. , Klassen T. , Araki H. , Frede S.
Published: April 2023

Bronze materials such as Ni-Al-bronze show exceptional performance against corrosion, erosive wear, and cavitation erosion due to their high fatigue strength and resistance to plastic deformation, and are thus used for ship propellers and in turbines, pumps, and other equipment where alternating stresses occur. Usually, the respective parts are cast, but in this study, a number of opportunities are evaluated to apply bronze as a coating to critical part surfaces. Initial experiments with cold gas spraying were promising enough to assess the use of warm spraying, a nitrogen-cooled HVOF process that provides similar particle impact velocities but higher particle temperatures, while still minimizing the effects of oxidation. The formation and performance of warm sprayed Ni-Al-bronze coatings was systematically investigated for different combustion pressures and nitrogen flow rates. Substrate preheating was also used to improve coating adhesion. The coatings obtained show low porosities, high strengths, and in some cases, cavitation resistance similar to that of the bulk material.
3D Tomography of Plasma Sprayed Cr-Clad Ni on Alumina
Authors: Wang A. Y. X. , Munroe P. R. , Tran A. T. T. , Hyland M. M.
Published: April 2023

In this work, a mechanically clad NiCr powder feedstock was deposited on alumina substrates by atmospheric plasma arc spraying. The resultant splats were analyzed for features such as interfacial bonding, splat classification and, critically, Cr distribution. Using a slice-and-view sectioning technique in a dual-beam FIB-SEM system, a representative splat exhibiting discrete Ni and Cr regions was physically deconstructed then reconstructed with visualization software to analyze individual layers with the splat. Although the powder feedstock contained Ni particles clad with clusters of Cr, the splats solidified into distinct layers of Ni and Cr with no signs of interaction between them. A model formulated based on this observation shows that the distribution of Cr cladding on the Ni particulates influences the amount and location of Cr around the solidified Ni splats.
Microstructure and Thermal Conductivity of Fe-Based Amorphous Coatings Prepared by HVOF Thermal Spraying
Authors: Wang L. , Zhou Z. , Yao H. H. , Wang Y. M. , Wu X. , He D. Y.
Published: April 2023

In this work, gas-atomized FeCr powders were deposited on aluminum substrates by HVOF spraying, forming dispersion strengthened coatings with a dense layered structure and low porosity. SEM, TEM, and XRD analyses show that the coatings primarily consist of amorphous matrix (40%) with precipitated nanocrystals and hard boride phases. A number of coating properties, including microhardness, bonding strength, and thermal conductivity, were measured and are correlated with spraying conditions.
Optimization to Fabrication Method of Al-Ni Composite for Shaped Charge Liner Applications
Authors: Lee S. , Park H. , Kim J. , Lee C. , Kim S. J. , Lee S.
Published: April 2023

In this study, arrested reactive milling (ARM) is used to prepare Al-Ni composite powder for deposition on copper liners via kinetic spraying. Among the main goals are to obtain a better understanding of how the milling process affects deposition efficiency and the reactivity of the coatings and to find a way to reduce the amount of remaining solid lubricant after milling. Al-Ni powders were produced under a wide range of conditions and heated to various temperatures to eliminate stearic acid. The powders were sprayed using fixed process parameters and deposition efficiencies, reactivities, and heat values were measured and are compared along with coating microstructures. The procedures used are described and the findings of the study are presented and discussed.
Fractal Analysis of Wear Debris for Plasma Sprayed MoS2/Ni-SiC-Y Solid Self-Lubricant Coatings
Authors: Yuan X. , Zha B. , Jiang L. , Yu Z.
Published: April 2023

This study assesses the effect of yttrium additions on plasma sprayed MoS2/Ni-SiC-Y coatings produced from particle-reinforced composite powders. It is shown that the microstructure of the self-lubricating coatings improves with the addition of yttrium, resulting in increased hardness and cohesive strength. The tribological properties of the coatings were also studied, showing that the ideal amount of yttrium is 12 wt% based on wear loss measurements and that the fractal dimension of sliding wear debris depends on the friction load as well as the mass fraction of yttrium.
A New Type of High-Performance Thermal Spray Powder with WB Reinforcement
Authors: Xie Y. , Xie L. , Wang H. , Yang Y. , Hou C. , Liu B. , Song X.
Published: April 2023

This study assesses the microstructure and mechanical properties of tungsten boride (WB) powder and cemented carbide coatings with WB additions. HVOF-sprayed layers produced from 60WC-30WB-10Co composite powders are compared with conventional 88WC-22Co and 86WC-10Co-4Cr coatings based on phase composition, hardness, wear resistance, and wear surface structure. The results indicate that Co reacts with WB during spraying, forming ternary phases (WCoB, W2CoB2) that increase hardness as well as sliding wear resistance.
Hot Corrosion Behavior of Multi-Layer Suspension Plasma Sprayed Gd2Zr2O7/YSZ Thermal Barrier Coatings
Authors: Jonnalagadda K. P. , Mahade S. , Curry N. , Li X.-H. , Markocsan N. , Nylén P. , Björklund S. , Peng R. L.
Published: April 2023

This study investigates the corrosion resistance Gd2Zr2O7/YSZ coatings and a YSZ layer of similar thickness. All coatings were produced by suspension plasma spraying, resulting in a columnar structure. Corrosion tests conducted at 900 °C for 8 h in a molten salt bath show that Gd2Zr2O7 is not as corrosion resistant as YSZ. Molten salts react with Gd2Zr2O7 producing GdVO4 along the surface as well as between the columns of the coating. The formation of GdVO4 between the columns, in combination with the low fracture toughness of Gd2Zr2O7, is likely responsible for the lower corrosion resistance. Furthermore, the presence of another layer of Gd2Zr2O7 on top of the Gd2Zr2O7/YSZ coating, to prevent salt infiltration, did not improve corrosion resistance.
High Entropy Alloy Coatings for Application as Bond Coating for Thermal Barrier Coating Systems
Authors: Bhattacharya R. , Senkov O. N. , Rai A.K. , Ma X. , Ruggiero P.
Published: April 2023

High-entropy alloys (HEAs) are well suited for use in high-temperature environments due to their combination of strength, ductility, thermal stability, and corrosion and wear resistance. In this study, NiCoCrAlSi-based HEA coatings are deposited by HVOF and air plasma spraying (APS) and their phases, microstructure, and composition are evaluated by means of XRD, SEM, and EDS analysis. The results show that BCC/B2 phases are the main constituent in HVOF coatings that were diffusion heat treated. APS coatings of the same composition, on the other hand, exhibited a two-phase structure consisting of L12 and BCC/B2 phases. The HEA coatings produced by HVOF were tested for oxidation resistance and their morphology and oxide scales were examined with the aim of developing a high-quality bond coat for thermal barrier coating (TBC) systems.
Effect of Content and Type of Reinforcing Particles on the Hardness and Wear Rate of Low-Pressure Cold-Sprayed TiC and B4C-based Metal-Matrix Composite Coatings
Authors: Lee Y. T. R. , Ashrafizadeh H. , Fisher G. , McDonald A.
Published: April 2023

This study evaluates the possibility of depositing hard B4C and TiC reinforcing particles in a Ni matrix using low-pressure cold spraying. It also investigates the effect of particle velocity and kinetic energy on deposition efficiency, microstructure, hardness, and wear resistance. B4C and TiC powders were blended at 50, 75, and 92 wt% carbide content with Ni powder comprising the remainder of the mixture. The impact velocity of sprayed carbide particles was calculated using a mathematical model based on the thermodynamics of compressible fluid flow through a converging-diverging nozzle. The model showed that the kinetic energy of TiC particles prior to impact was three times smaller than that of B4C, resulting in a higher carbide content (18 wt% compared to 8 wt%) due to reduced fracture and rebound of the TiC particles. Although the hardness values of both coatings are within the range of cold-sprayed WC-Co-Ni, wear rates were found to be high.
Tribology and Nanoindentation Study of Suspension HVOF Thermally Sprayed Alumina Coating
Authors: Hussain T. , Shaw E. C. , Pala Z. , Xu F. , Ang A. S. M.
Published: April 2023

In this study, a water-based corundum suspension was used to deposit 60 μm alumina coatings onto carbon steel substrates by HVOF spraying. The aim was to develop thin coatings with superior wear properties. Hydrogen was used as a fuel gas and process parameters were varied to determine their effect on microstructure and properties. Coating microstructure was examined by SEM to assess particle melting and morphology and XRD was used to study the phase transformation of the feedstock suspension. At higher combustion flame energy, the coating transformed primarily to gamma alumina, while at lower energy, it was found to be a mixture of alpha and gamma alumina. Nanoindentation tests were used to measure the hardness and elastic modulus of individual phases. Ball-on-plate wear tests helped reveal the relationship between wear performance and the alpha-gamma ratios in the coatings.
The Main Issues to Address in Modeling Plasma Spray Torch Operation
Authors: Chazelas C. , Vardelle A. , Trelles J. P.
Published: April 2023

Most models used to simulate plasma torch operation consider only the gas domain with the electrodes included as boundary conditions, imposing a current density profile and temperature at the cathode tip. In order to achieve more realistic simulations, it is necessary to include the electrodes and arc column in the calculation domain. This paper discusses some of the issues, factors, and considerations involved in modeling arc-cathode and arc-anode interactions and their effect on the plasma jet. Descriptions of the arc column and plasma jet are based on the coupling of electromagnetic and fluid equations and require thermodynamic, transport, and radiative property values of the gas mixture. In order to capture the stochastic behavior of the arc, it is assumed that the model is 3D and time-dependent.
Fracture Characteristics of High-Velocity Suspension Flame-Sprayed Aluminum Oxide Coatings
Authors: Kiilakoski J. , Lutoschkin A. , Plachetta M. , Apostol M. , Koivuluoto H. , Müller P. , Killinger A. , Vuoristo P.
Published: April 2023

The aim of this work is to evaluate the brittleness of suspension sprayed aluminum oxide coatings with various methods, including Vickers indentation fracture toughness, four-point bending, and high-velocity particle impact testing. Coatings were applied via high-velocity suspension flame spraying (HVSFS) using suspensions of isopropanol and water solvents. HVOF-sprayed Al2O3 powder feedstock was used as a reference. The tests are described and the results are presented and discussed.
Stress Analysis and Failure Mechanisms of Plasma-Sprayed Thermal Barrier Coatings
Authors: Yang J. , Wang L. , Li D. , Zhong X. , Zhao H. , Tao S.
Published: April 2023

Yttria stabilized zirconia coatings were deposited by plasma spraying and heat treated in air at 1100 °C for 50-200 h. Residual stresses in the ceramic topcoat and the thermally grown oxide (TGO) layer were measured before and after thermal exposure. After 50 h of exposure, tensile stress in the as-sprayed topcoat changed to compressive, which then increased with additional exposure time up to 150 h. The average compressive stresses in the cross-section of the TGO layer are shown to be higher than those on the surface of the oxide. In addition to shedding light on the nature and evolution of stresses in plasma-sprayed thermal barrier coating (TBC) systems, the results of the study also provide insights on crack initiation and propagation in the ceramic topcoat and at the topcoat-TGO-bond coat interface and its role in TBC failures.
Characterization of YSZ Coatings Deposited by Conventional dc and CO2-CH4 Torches
Authors: Salimijazi H. R. , Ghasemi R. , Mostaghimi J. , Pershin L.
Published: April 2023

In the present work, hollow sphere YSZ powders were deposited by dc plasma spraying using a mixture of CO2 and CH4 gases. The plasma plume was monitored with an IR camera and in-flight particle velocity and temperature distributions were recorded at impact. Single splats were collected on mirror polished stainless steel and, along with coating samples, were characterized and compared to splats and coatings deposited by conventional argon spraying. In the case of CO2-CH4 spraying, particle temperatures were at least 100 °C higher than the YSZ melting point and almost all splats were completely melted. Coating surfaces were also found to be smoother, indicating less unmelted or partially melted splats.
Microstructure and Properties of FeCrNbBSiC Coating Prepared by Wire-Arc Spraying Process
Authors: Qian Z. H. , Zhou Z. , Yao H. H. , Wu X. , Wang Y. M. , He D.Y.
Published: April 2023

In this study, FeCrNbBSiC coatings are deposited on aluminum alloy 4042 substrates by wire arc spraying and their microstructure, phase composition, hardness, bonding strength, and thermal conductivity are evaluated in comparison with a commercial 316L stainless steel coating. The FeCrNbBSiC samples were found to have a dense and homogeneous lamellar microstructure with much less oxide inclusions than the stainless steel layer. The iron-based coatings were also much harder, mainly due to their composite structure with amorphous and nanocrystalline phases, and their bonding strength was slightly higher. In thermal conductivity testing, the FeCrNbBSiC layers were found to have thermal insulation properties close to that of conventional (YSZ) TBCs, making them a good candidate for engineering use.
Highly Economical Fe-Based Protective Coating System by Novel Material Design and Full Utilization of the Atomized Powder
Authors: Bobzin K. , Zhao L. , Öte M. , Königstein T.
Published: April 2023

In this work, the aim is to develop a cost-effective coating to protect cast iron and carbon steel from corrosion and wear. An alloy with a composition of FeCr25Mn10BC was designed that could be readily converted to powder form by gas atomization. Different sized powders were produced, characterized, and subsequently sprayed using a three-cathode air plasma generator. It was found that fine powders with fractions of -25 +10 μm and -10 μm had a much higher affinity to oxidation than coarser ones. Nevertheless, using suitable parameters, dense coatings with low oxide content could be realized even with the finest powder. The results show that full utilization of the powder is achievable due to the wide parameter window of three-cathode plasma spraying and that the average deposition efficiency is more than 70%. In addition to savings in material and processing costs, the new alloy system provides greater wear resistance than stainless steel coatings and exhibits significantly higher corrosion resistance than unprotected cast iron and carbon steel.
Fe-Based Powder Alloys Deposited by HVOF and HVAF for Sliding Wear Applications
Authors: Dizdar S.
Published: April 2023

This study compares the wear performance of thermally sprayed iron coatings with that of electrolytic hard chrome (EHC) plating. Three Fe-based alloy powders (FeSP529, FeSP586, 6AB) were deposited on S355 structural steel plates by HVOF and HVAF spraying and the resulting coatings and plating samples were subjected to dry sliding wear tests using a block-on-ring setup. Wear maps for all three Fe-based powder alloys are similar, showing regions of plasticity dominated wear, wear transition, and oxidational wear as a function of sliding velocity. More importantly, the wear rates of the sprayed coatings were ten times lower than those of the EHC plating samples.
Nanotopographical Features of Plasma Sprayed Coatings on Bone Implant Surfaces
Authors: Wang G. , Song X. , Zhao X.
Published: April 2023

Previous studies have shown that nanostructured coatings produced by plasma spraying can stimulate cellular activity and promote bone healing. Since then, a number of studies have been conducted to better understand how coating nanotopography can be controlled and how it influences bioactivity and healing. This paper reviews some of the key findings in three areas: the effects of nanotopography on bone cell adhesion, the effects of nanotopography on bone-like apatite formation in simulated body fluid, and how to refine the nanotopography of plasma-sprayed coatings.
Effect of Nitric Acid Corrosion on the Luminescent Intensity of Plasma Sprayed YAG:Ce Coatings
Authors: Zeng P. , Wang H. , Wang W. , Yu J. , Wu L.
Published: April 2023

This study assesses the effect of acid corrosion on the luminescence of YAG:Ce coatings. The feedstock powder is prepared by high-temperature solid phase synthesis and the coatings are deposited by air plasma spraying. Microstructure and phase composition are characterized and the effect of acid immersion duration on luminescent intensity is measured. It is found that the luminescent properties of YAG:Ce3+ coatings have a tendency to fluctuate with immersion time, which appears to be related to phase composition.
Sulfidation Behavior of Plasma-Sprayed Al-Mo Coatings at High Temperature
Authors: Wu L. , Wang W. , Yu J.
Published: April 2023

This work investigates the effects of sulfidation on plasma-sprayed Al-Mo and Mo coatings. Pure Mo powder and Al-Mo powder mixtures were sprayed on Inconel substrates with either a NiCrAlY or Mo bond coat. Oxidation and sulfidation tests were carried out in air and Ar-S2 atmospheres, respectively, at temperatures of 973, 1073, and 1173 K. Coating samples were evaluated before and after testing via SEM and XRD analysis and weight measurements. The results show that Al-Mo coatings with a Mo bond layer provided the best protection against high-temperature oxidation and sulfidation corrosion.
Effect of Substrate Preheating on the Bonding Strength of Detonation Sprayed WC10Co4Cr Coatings
Authors: Gao Y. , Hou Y. , Gao J.
Published: April 2023

This study investigates the influence of substrate preheating on the microstructure, hardness, and adhesion of detonation sprayed WC-CoCr coatings. Using commercially available powders, coating samples are deposited on low carbon steel substrates, some at room temperature and some having been preheated to 300°C. Test results show that the coatings deposited on preheated substrates are harder, more crack resistant, and better adhered, with no significant differences in microstructure. After tensile testing, fracture surfaces and interfaces were investigated, showing how fracture behavior, along with hardness and bonding strength, correlate with phase composition and particle impact conditions.
Impedance Analysis of 7YSZ Thermal Barrier Coatings During High-Temperature Oxidation
Authors: Chen W.-L. , Liu M. , Zhang J.-F.
Published: April 2023

This work evaluates the high-temperature oxidation behavior of thermal barrier coatings by means of impedance spectroscopy. TBCs consisting of YSZ topcoats and NiCoCrAlYTa bond coats were deposited on Ni-based superalloy substrates by atmospheric plasma spraying. Test specimens were heated in air at 1000 °C for different periods of time from 5 h to 250 h. SEM-EDS analysis of the thermally grown oxide (TGO) shows that it mainly contains alumina and grew at a parabolic rate with increasing oxidation time. The resistance of the TGO, as determined by impedance spectroscopy, was found to increase at similar rate. Impedance spectroscopy also revealed an increase in YSZ grain boundary resistance corresponding to grain boundary cracking that occurred in the first 50 h of heating. The YSZ grain boundary resistance remained relatively constant over the interval of 50 to 150 h, but showed a slight decrease beyond 150 h mainly due to sintering effects.
Electrochemical Impedance Spectroscopy of Thermally Sprayed Aluminum in Synthetic Seawater
Authors: Paul S.
Published: April 2023

Commercially pure aluminum was arc sprayed on low-carbon manganese steel and electrochemical impedance spectroscopy (EIS) was carried on coating samples in a simulated marine immersion environment at 35 °C. A simple pore network circuit model was used to analyze the data and calculate the corrosion rate, which was estimated to be 5-15 μm/y from the charge transfer resistance value. After 9 months of exposure, the actual corrosion rate was found to be ~5 μm/y. The mechanism of protection offered by thermally sprayed aluminum (TSA) coatings is discussed.
Microstructure and Wear Resistance of Atmospheric-Plasma-Sprayed AlCoCrFeNiTi High-Entropy Alloy Coating
Authors: Xiong W. , Tian L.-H. , Liu C. , Lu S.
Published: April 2023

In this work, atmospheric plasma spraying was used to deposit an equiatomic AlCoCrFeNiTi high-entropy alloy (HEA) coating with a thickness of 236 μm, a porosity of 1.6%, and an adhesive strength of 50.3 MPa. The as-sprayed coating mainly contained BCC1 and BCC2 phases, with only a trace amount of the FCC phase. Microhardness was four times that of 316 stainless steel and the volume wear rate at room temperature was one-fourth that of the substrate material. The wear rate decreased with increasing temperature from 25°C to 700°C, then increased from 700°C to 900°C. Over that range, the wear mechanism changed from delamination wear to oxidation and adhesion wear.
Influence of the Segmentation Crack on the Stress Distribution and Failure Behavior of the Thick Thermal Barrier Coatings Fabricated by Atmospheric Plasma Spraying: A Numerical Simulation Study
Authors: Wang L. , Yang J. , Li D. , Zhao H. , Zhong X. , Shao F. , Liu C. , Tao S. , Ding C.
Published: April 2023

In this work, finite element modeling is used to investigate the influence of segmentation cracks on stress distribution and failure in thermal barrier coatings deposited by atmospheric plasma spraying. The results indicate that the presence of segmentation cracks does not improve thermal insulation, but it may be beneficial in regard to thermal shock resistance, depending on crack density, and residual stress around crack tips, depending on crack length. It may also improve strain tolerance, which is affected by crack density as well as length. A model is proposed to explain the mechanism of failure in thick TBCs exposed to thermal shock. Damage caused by thermal shock can be attributed to the propagation of segmentation cracks and the formation of horizontal cracks at the bond coat-topcoat interface.
Introduction of Micro Resin Fragments with Ceramic Nanoparticles into Plasma Flame to Create Fine Coated Layers
Authors: Katsuki M. , Harada H. , Kirihara S.
Published: April 2023

A new nanoparticle plasma spray process has been developed that uses conventional powder feeders and injectors to produce fine ceramic coatings at high deposition rates. This paper explains how powder feedstocks are prepared and how the resulting coatings compare with coatings by other methods. The feedstock used in the demonstration was produced by adding YSZ nanoparticles to an acrylic liquid resin, which was then solidified, crushed, and screened. SEM images show that the nanoparticles are well dispersed throughout the resin fragments. In the plasma flame, the resin fragments burn down as the nanoparticles are heated and accelerated toward the substrate, producing fine zirconia layers free of microcracks and pores as observed by SEM. The presence of carbon deriving from the resin material is dealt with by post-process heating at different temperatures, the effect of which is assessed by means of thermogravimetry. Vickers hardness of the YSZ phase was measured to estimate the sintered density.
Spraying of Aluminum Nitride-Alumina-Yttria Mixtures in Nitrogen
Authors: Shahien M. , Yamada M. , Fukumoto M.
Published: April 2023

This study investigates the feasibility of spraying aluminum nitride-alumina-yttria mixtures in a nitrogen plasma ambient. Coatings consisting of h-AlN, c-AlN, Al5O6N, and γ-Al2O3 with small amounts of α-Al2O3 and aluminum-yttrium oxide phases were produced. Although using the Y2O3 additives significantly affected the process and microstructure, it did not achieve the high thermal conductivity desired in as-sprayed coatings. However, a high thermal conductivity (>90 W/m·K) AlN coating was fabricated by increasing the AlN content and enhancing sintering during heat treatment.
Nonvolatile Control of Metal-Insulator Transition in VO2 and Its Applications
Authors: Gim Hyeongyu , Hong Kootak
Published: April 2023

With the advent of the 4th industrial revolution era, there has been a high demand for high-performance electronic devices capable of collecting, storing, and calculating vast amounts of data. Vanadium dioxide (VO2) is considered an attractive candidate for next-generation electronic devices as a prototypical strongly correlated material exhibiting a metal-insulator transition (MIT) accompanied by huge electrical resistivity changes in a few nanoseconds. The nonvolatile control of the MIT in VO2 has recently been the subject of intensive research. In this report, we review recent advancements in the field of nonvolatile control of MIT in VO2, using electrochemical redox reactions, inverse piezoelectric effect, and ferroelectric polarization, and their potential to develop high-performance next-generation electronic devices.
A way to utilize SOFC systems: The energy solution for next-generation smart farm
Authors: Han Gwangwoo , Hong Jong-Eun , Lee Wang-Je , Lee Kyoung-Ho , Joo Hong-Jin , An Young-Sub , Joh Dong Woo , Kim Hye-Sung , Lee Seung-Bok , Lim Tak-Hyoung , Park Seok Joo , Song Rak-Hyun
Published: April 2023

In the field of food and agriculture, fuel cell-based energy supply technology is gaining much attention for sustainable food systems with carbon neutrality by 2050. Previous studies have focused on the electricity balance using polymer electrolyte fuel cells (PEMFCs) without considering the temperature quality to maintain the environmental conditions required in smart farms. However, this study proposes a system that can provide all four energy sources (electricity, cooling, heating, and CO2) required by smart farms by using solid oxide fuel cells (SOFC), which can utilize high-quality heat. To confirm the feasibility of the proposed idea, we demonstrate the world's first 10 kW-class SOFC-based integrated system for a smart farm in Jinju, South Korea. The system's core components consist of a SOFC system, a hot thermal storage system, a cold thermal storage system, and a CO2 supply system. In this study, the applicability of the proposed system is verified by the experimental results of the effective production of cold and hot heat required by smart farms. In addition, the technical problems encountered during the demonstration are presented. In doing so, we suggest the direction of more economical and sustainable SOFC technology development for smart farm applications.
Recent progress of the p-type oxide thin films for transistor applications: Nickel oxide, Tin oxide, and Copper oxide
Authors: Choe Minki , Jeon Dahui , Hwang Inhong , Baek In-Hwan
Published: April 2023

Over the past decade, many research groups have been striving to develop high-performance p-type switching oxide materials for implementing complementary metal–oxide–semiconductor (CMOS) thin film devices. However, realizing p-type oxide thin film transistors (TFTs) whose electrical properties are comparable to n-type oxide TFTs has been challenging. This is because of inherent characteristics of p-type oxide materials such as the high formation energy of native acceptors and high hole effective mass caused by localized hole transport path. Developing a p-type oxide with a delocalized hole transport pathway and low hole formation energy is crucial for the production of CMOS circuits utilizing oxide thin films. NiO, SnO, and CuOx are being actively studied as candidate materials that satisfy these requirements. This review discusses the latest advances in the synthesis method of p-type binary oxide thin films and the approach for electrical performance enhancement.
Elucidating degradation mechanisms of Co-free high-Ni layered oxide cathodes for Li-ion batteries via advanced X-ray-based characterization methods
Authors: Hyun Hyejeong , Lim Jongwoo
Published: April 2023

High-Ni layered oxide cathodes without Co are being investigated as potential cathode materials for Li-ion batteries with high energy density. By decreasing the Co content, these cathodes not only boost energy density but also alleviate concerns about the supply instability and fluctuating cost of Co raw materials. However, the elevated Ni content in the layered oxides causes distinct chemo-mechanical degradation mechanisms that inhibit their commercial application. In order to gain insight into the degradation process at various scales, from the atomic to the particle and the electrode levels, and to devise ways to prevent degradation, multi-scale characterization methods are essential. In this review, we critically evaluate the role of Co substitution in high-Ni layered oxides and the impact of Co content on the chemo-mechanical degradation process. Furthermore, the use of advanced X-ray-based characterization methods, which have helped shed light on the degradation mechanisms of high-Ni cathodes, is also discussed.
Spomenik Presvetom Trojstvu u Vinkovcima i njegova tipološka ishodišta
Authors: Zajec Vlasta
Published: April 2023

Spomenik Presvetom Trojstvu u Vinkovcima djelo je klasicističkih stilskih obilježja koje su 1845. godine dali sagraditi članovi gradskih cehova. Pripada malobrojnoj tipološkoj skupini spomenika čiju jezgru čine tri trokutno raspoređena stupa čime se na vizualno sugestivan način prikazuje simbolika Presvetog Trojstva i jedini je primjer takvog rješenja u Hrvatskoj. Za razliku od dosadašnjih tumačenja koja kao ishodišni primjer tipa prepoznaju bečki Josephssäule, u radu se upućuje na moguće bavarsko podrijetlo rješenja. Slijedom utjecaja spomenika Johanna Martina Fischera u Bólyju (1775. – 1776.), tip je osobitu popularnost zadobio tijekom 19. stoljeća na području mađarskog dijela Baranje. Na tom je tragu i rješenje spomenika u Vinkovcima, što upućuje na podrijetlo utjecaja odnosno predloška, eventualno i majstora.
Neoklasicistički hram u sklopu Školskog foruma – povijest gradnje i prenamjene
Authors: Kraševac Irena , Šverko Ana
Published: April 2023

U članku se na temelju dosad neistraženoga gradiva pohranjenoga u Hrvatskom državnom arhivu u Zagrebu prvi put donosi detaljna povijest gradnje i prenamjene zgrade podignute u formi stiliziranoga antičkog hrama u sklopu zagrebačkog kompleksa srednjih škola 1895. godine, čiji je idejni začetnik Izidor Kršnjavi. Prati se geneza forme i funkcije ove građevine od prvih zamisli do prenamjene već gotovog projekta muzeja sadrenih odljeva antičke skulpture u gimnastičku dvoranu – gombaonu. Autorice na temelju istraživanja sačuvanih nacrta i podataka o izgradnji ujedno rasvjetljavaju atribuciju gombaone.
‘Every Person Counts’
Authors: Fechter Anne-Meike
Published: April 2023

As multiple forms of ‘vernacular humanitarianism’ are emerging, ordinary citizens, active locally or internationally, play an increasing part. Their interventions face the challenge of scale, and scale-ability of their activities. What can be their role if they only engage with small groups of people? How do they attribute meaning to these interventions, given that the scope of the problem is always larger than what they can hope to achieve? Drawing on research with privately funded humanitarian initiatives in Cambodia, the article argues that in order to accommodate the partialness of their endeavours, they deploy a particular scale, namely that ‘every person counts’. The practices carried out under this logic contain singular acts of care, and lives being transformed. Other scales are being brought into play, such as an individual ‘paying it forward’ by supporting others and thus effecting change in wider society.

En observant l’émergence de ‘l'humanitarisme vernaculaire’ dans toute sa diversité, les citoyens ordinaires contribuent à ce phénomène au niveau local ou international. Leurs interventions pourraient garantir l'innovation et les solutions locales ; mais, au même temps, ces interventions sont confrontées par un double défi concernant leur échelle et leur capacité d'extension. Existe-t-il un rôle pour l'humanitarisme de tous les jours qui se limite aux activités concernant des petits groupes d'individus ? Comment trouve-t-on le sens de ces interventions, compte tenu de l'ampleur du problème qui dépasse toutes les bonnes intentions pour faire du bien ? Cet article, basé sur la recherche auprès des initiatives du parrainage privé au Cambodge, montre que ces activités utilisent l’échelle dit ‘chaque personne compte’ pour pallier leurs insuffisances. Les actions guidées par ce raisonnement incluent des gestes particuliers du soin et des améliorations de vie. Il existe d'autres échelles pour effectuer des transformations sociales, comme un individu qui ‘paie d'avance’ en aidant les autres ; c'est un point essentiel. Au lieu d'envisager une séparation entre l’échelle de l'individu et l’échelle de nombreuses personnes, les acteurs de l'humanitarisme envisagent des liens. D'une manière plus générale, ces pratiques de tous les jours proposent que l'approche à l'extension de l'humanitarisme pourrait également rendre visible sa diversité.
The Desire to Help
Authors: Fengjiang Jiazhi
Published: April 2023

The tremendous growth in search and rescue volunteerism in China of the past decade marks a shift from state monopoly to growing social participation in emergency governance related to disasters and various other forms of emergency. In some respects, the Chinese case can be contextualised in the global rise of ‘vernacular humanitarianism’. This article joins recent anthropologists’ and historians’ attempts to de-centre and pluralise humanitarianism, which has so far been dominated by the paradigms of Northern-led and highly institutionalised international regimes. Drawing on ethnographic research in southeast China, it suggests that the lens of vernacular imaginaries and desire is particularly fruitful for articulating how people act across various social and cultural spheres that go beyond the dichotomous scholarly paradigms of state-centric interpellation and individual compassions/resistance in the Chinese context. It also allows us to rescue the plural political potentials of humanitarianism from cynicisms regarding the major paradigms of humanitarianism.

Depuis dix ans, le bénévolat des secouristes en Chine a beaucoup augmenté et cette activité constitue un changement du monopole d’état vers une participation sociale croissante dans la gouvernance en rapport avec des sinistres et autres formes d'urgences, y compris les efforts de trouver des personnes disparues. En quelque sorte, le cas chinois correspond à l'expansion globale de ‘l'humanitarisme volontaire’. En utilisant le terme analytique de ‘l'humanitarisme volontaire’, cet article poursuit les efforts d'historiens et d'anthropologues pour décentraliser et diversifier les notions de l'aide humanitaire. Ces notions ont été influencées trop longtemps par des paradigmes du Nord et par des régimes internationaux hyper-institutionalisés. L'article est fondé sur la recherche ethnographique dans le sud-est de la Chine. Elle propose que la volonté des bénévoles d'aider est en lien avec leur conceptualisation d'urgences, et la vision d'un personnage militaire qui produit la sociabilité et la matérialité soutenant l'expansion d'assistance et de ses opérations régulières. Les concepts de l'imaginaire vernaculaire et du désir sont fructueux pour décrire les actions de gens dans de nombreux domaines sociales et culturels qui dépassent la dichotomie universitaire de l'interpellation étatique et les compassions/résistances des individus dans le contexte chinois. Nous pourrions ainsi sauver la pluralité des possibilités politiques dans l'humanitarisme et échapper aux cynismes concernant ses paradigmes majeurs.
МЕТОД ПОСЛІДОВНИХ НАБЛИЖЕНЬ ДЛЯ ЗНАХОДЖЕННЯ ОПТИМАЛЬНОГО РОЗПОДІЛУ ПОТОКІВ ВИМІРЮВАНОЇ ІНФОРМАЦІЇ В МЕРЕЖІ НАЗЕМНИХ СТАНЦІЙ СУПУТНИКОВИХ РАДІОНАВІГАЦІЙНИХ СИСТЕМ
Authors: ЗАЩЕПКІНА Наталія , СОКІРІНА Валерія
Published: April 2023

В умовах функціонування мережі, коли час обробки вимірювальних  сигналів у вузлі комутації займає певний час, а важливість інформації має різні значення, виникає необхідність організації черг заявок на обслуговування інформації. Основна мета такої організації полягає в зменшенні втрат інформації в мережі при передачі за умов використання транзитних шляхів. Динамічна перебудова черги на вузлах в свою чергу забезпечує зменшення втрат заявок з причини їх «старіння». Структура системи динамічного управління потоками  передбачає особливе місце в комутаційній підсистемі системі управління, яка здійснює контроль за вимірюванням, збором, обробкою і надалі переміщенням трафіку в мережах, розподілом мережевих комутаційних ресурсів відповідно до заданих пріоритетів передачі інформації. Очевидно, що застосування в складі комутаційної структури систем динамічного управління інформаційними потоками вимірювань забезпечить необхідну якість функціонування мережі, оперативну реакцію на мало інерційні ситуації в реальному масштабі часу. Динамічне управління розподілом інформаційних  потоків може бути здійснено як за рахунок управління структурою мережі шляхом зміни ємності пучків каналів, або перерозподілом каналів мережі при зміні інформаційних взаємодій між окремими парами вузлів комутації, так і за рахунок управління шляхами передачі потоків без зміни структури мережі. Очевидно, що другий спосіб є як економічно, так і апаратно більш вигідним, оскільки зміни структури мережі мінімальні.