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Fe-based bulk metallic glasses (BMGs) with high boron content have potential application as a coating material used in the framework for storing spent nuclear fuels to support their safe long-term disposal. The high glass forming ability (GFA) and large supercooled liquid region are therefore required for such Fe-based BMGs in either the glassy powder fabrication or the subsequent coating spraying. In order to meet these requirements, the influence of Nb content on the GFA of Fe57Cr10Zr8B18Mo7−xNbx (x=1–5, at.%) alloys was investigated, as Nb has positive roles in GFA and thermal stability of BMGs. The results indicate that a fully amorphous phase in the as-cast samples with 3 mm in diameter is obtained for both the Fe57Cr10Zr8B18Mo5Nb2 and Fe57Cr10Zr8B18Mo4Nb3 alloys. The corresponding supercooled liquid regions of the two BMGs are 78 K and 71 K, respectively. The mechanism for improving their GFA was analyzed based on the principle of metal solidification, the parameters for glass formation and thermal properties of the alloys. The compression strength and Vicker's hardness of the two BMGs are 1,950 MPa and 1,310 HV, 2,062 MPa and 1,180 HV, respectively. The developed BMGs with high B content, good GFA, and very high hardness can be used as coating materials to the framework for spent nuclear fuels. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In view of the key technical problems of ultrahigh-speed laser cladding, this paper has studied the influence of different laser power, powder feeding rate, and carrier gas velocity on the formation of the cladding layer. A theoretical model of the powder flow field in the laser cladding process has been established. An energy attenuation algorithm based on the powder shading ratio has been designed, and the particle thermal field has been analyzed. We verified their feasibility with four radially symmetrical powder flow nozzles and extended them to the annular cladding nozzles. It is found that the powder spot temperature can be increased by increasing the laser power and setting powder focus point 0–2 mm above the laser focus point, and the utilization of laser energy in powder can be improved by reducing the particle size and increasing the powder feeding rate and carrier gas velocity. The results provide theoretical references for the application of ultrahigh-speed laser cladding on the surface strengthening of shaft components. [ABSTRACT FROM AUTHOR]

In this study, a novel functionalized graphene oxide(GO) sheet of polyaniline(PANI) was prepared by in situ polymerization of aniline. Fourier transform infrared spectroscopy (FTIR), X-ray diffractometer (XRD) and scanning electron microscope (SEM) indicated the successful polymerization of aniline on GO tablets, and PANI was uniformly inserted into the GO lamellas that benefited the dispersion of PAGO. The anticorrosion properties of PAGO-PVC/EP coatings with different contents were analyzed and compared with PAGO-0 and the GO coatings. Electrochemical analysis showed that an appropriate amount of PAGO (0.5wt%) could significantly improve the long-term corrosion resistance of the coating. Its excellent corrosion resistance was attributed to two parts: (1) PAGO had good dispersion and could improve the barrier property of the coating to block H2O, O2 and electrolytes from penetrating to the steel substrate; (2) PANI with complete electrical activity could timely transfer the electrons lost from the base to the coating surface, and form a passivation film composed of Fe3O4 and Fe2O3 by induction. The barrier property of GO and the self-healing ability of PANI made PAGO-based PVC/EP coatings excellent in corrosion resistance. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To probe into the mechanism of Xiaoer Qingrehuaji powder in the treatment of acute infantile convulsion. METHODS: Network pharmacology approach was adopted to construct biomolecular network related to Xiaoer Qingrehuaji powder and conduct bioinformatics annotation and analysis. Molecular docking on compounds with key targets in Xiaoer Qingrehuaji powder was performed with the help of AutoDock Vina software. RESULTS: A total of 122 potential active compounds, I 255 predicted targets and 1 023 targets related to pediatric acute convulsion were obtained from Xiaoer Qingrehuaji powder. Totally 304 potential targets for efficacy were derived from the " compound-target-disease" network, which had involved biological process including regulation of membrane potential, response to antibacterial drugs and regulation of chemical synaptic transmission; cellular components including ion channel complexes, transmembrane transport protein complexes and neuronal cell bodies; molecular functions including gated channel activity, ion channel activity and passive transmembrane transport protein activity; signal pathways including neuroactive ligand-receptor interaction, Alzheimer' s disease, MAPK and cAMP. Results of molecular docking showed good binding ability ( all Affinity <-5 kcaVmol) between 36 compounds and their corresponding key targets. CONCLUSIONS: The mechanism of Xiaoer Qingrehuaji powder in the treatment of pediatric acute convulsion may be related to biological function including regulation of membrane potential, neurological function regulation, neuroactive ligand-receptor interaction and inflammatory response, the targets of DRD2, OPRKI, GABBR2 and PIK3CA can be focused on. [ABSTRACT FROM AUTHOR]

Thermal spray processing parameters need to be optimised to mitigate decarburisation and oxidation of carbide-based coatings that causes unacceptable brittleness. In the present work, a theoretical model was developed to optimise kerosene fuelled high-velocity oxy-fuel (HVOF) flame characteristics and spray parameters for producing high-quality WC-NiCr coatings using finer feedstock of particle size distribution of – 30 + 5 μm. The model suggested an oxygen-to-kerosene ratio of 3.3 and a shorter torch barrel to avoid decarburisation in coatings. In total four parameter sets suggested by the theoretical model were selected to spray the fine-cut powder using a 100 mm long torch barrel. The developed theoretical framework was successful to provide optimised set of HVOF spray parameters to deposit high-quality fine carbide coatings with less decarburisation. Also, the coatings deposited using the optimised set of parameters exhibited the best performance in terms of low porosity, inter-splat cracks, brittleness, as-spray surface roughness, and corrosion resistance. Hence, the optimised parameters can be used to produce a finer as-sprayed finish, thereby demonstrating the potential in reducing grinding efforts. [Display omitted] • Excessive oxygen in HVOF flame led to decarburisation in WC-NiCr coatings. • Optimisation of spray parameters to leads to crack free hard coatings. • Successful deposition of fine carbides using kerosene fuelled HVOF spray. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fluorine-doped amorphous carbon thin film coated graphite anodes. • Semi-ionic C–F abundant surface chemistry of interfacial coating film. • Compatibility with non-flammable sulfone-based electrolytes. • Ultrafast Li-ion and electron kinetics of graphite anodes with sulfone electrolytes. To achieve full commercialization of Li-ion batteries, fire safety issues, which primarily start and accelerate from the electrode/electrolyte interface, should be resolved. Therefore, ionic liquids containing sulfone-based Li salts and solvents have been demonstrated to exhibit higher flame-retardancy than carbonate-based electrolytes. However, these sulfone-based electrolytes (sulfone EL) still face the challenges of sluggish Li-ion diffusivity of the electrolyte itself and poor compatibility especially with graphite anodes, lowering the specific capacity and high rate capability of the anodes. Herein, interface engineering was achieved by introducing a fluorine-doped amorphous carbon thin film coating (sub-20 nm) between graphite and sulfone EL, thereby simultaneously enhancing the ultrafast rate capability and flame-retardancy. The semi-ionic C–F abundant surface chemistry of graphite (F–C/Gra) not only induces robust solid electrolyte interface (SEI) formation with a LiF-rich composition and moderate thickness, but it also promotes fast-rated electron transfer into the graphite interior, which differs from bare graphite in sulfone EL. Surprisingly, this robust SEI formation on F–C/Gra was achieved at an elevated temperature (60 °C), enhancing Li-ion transport kinetics and allowing graphite-based anodes to achieve ultrafast longevity (discharge capacity of 152.6 mAh/g after 300 cycles at 1000 mA/g, 60 °C) even under harsh conditions. [ABSTRACT FROM AUTHOR]

• Composite coatings based on block copolymers by electrophoretic deposition technique. • Presence of a hydroxyapatite layer over composite coatings after soaking in simulated-body fluid. • Poly(dimethylsiloxane- b -caprolactone) copolymer showed a good compatibility with Bioglass®. • Poly(dimethylsiloxane- b -caprolactone) showed a good compatibility with tricalcium phosphate. • Potential bioactive coatings on stainless steel by using electrophoretic deposition technique. The aim of this work focused on the synthesis of composite coatings based on poly(dimethylsiloxane- block -ε-caprolactone), Bioglass® (BG) and tricalcium phosphate (TCP) particles deposited on stainless steel plates obtained by electrophoretic deposition (EPD) technique. In vitro assessment was performed in simulated body fluid (SBF) to evaluate the potential uses of these coatings in tissue engineering. Thermal characterization from thermogravimetric analysis (TGA) revealed that experimental [Polymer]:[mineral] e wt/wt ratios were 32:68 and 26:74 for coatings with BG and TCP, respectively. In addition, all coatings exhibited thicknesses ranging from 45.3 μm to 59.9 μm. Finally, the growth of a hydroxyapatite (HA) layer on the coatings, after soaking in simulated body fluid (SBF), was evidenced by X-ray diffraction analysis. This last result suggests that the obtained coatings could be used as promising materials in bone tissue regeneration. [ABSTRACT FROM AUTHOR]

In order to realize high-performance joining of misoriented single crystal superalloys, a rapid partial transient liquid phase (PTLP) bonding process was proposed in this work. By using a mixture of nickel-chromium-tantalum (Ni-Cr-Ta) and nickel-based superalloy (FGH4096) powders as filler material, high-performance PTLP joints of misoriented single crystal superalloys (DD5) were obtained. The joint bonded at 1260 °C consisted of an epitaxial growth zone (EGZ) containing γ/γ' derived from DD5 and a polycrystalline zone (PCZ) located at the center of the joining layer, in which tantalum dichromide (TaCr 2) and tantalum carbide (TaC) existed at the grain boundaries. As the Ni-Cr-Ta content increased, the voids in the joints decreased while the Ta-rich compounds increased and the grain size decreased. With the holding time increasing, the Ta-rich compounds decreased while the grain size increasing. The optimum process was 60 min at 1260℃ with the Ni-Cr-Ta content of 60 wt%. Due to the specially designed filler metal without boron (B) and silicon (Si) elements, there was no low-melting eutectic or compound in the PTLP joints, which ensure the joint with high-performance at elevated temperatures. Compared with transient liquid phase (TLP) bonding process, the PTLP bonding process achieved rapid isothermal solidification with the help of the short-distance and large-area diffusion mechanism between the Ni-Cr-Ta (liquid phase) and FGH4096/DD5. The presence of PCZ prevented the formation of penetrating grain boundary, and thus eliminated the effect of misorientation between two base metals on the performance of the joints. The tensile strengths at room temperature and 980 °C of the PTLP joints which obtained with the optimum process were 926.05 MPa and 681.96 MPa, respectively, up to 90.32% and 92.25% of the base metal. The PTLP bonding process proposed in the present work may provide a high efficiency approach to achieve high-performance single crystal superalloy joint, which is also gifted a major advantage of B/Si-free. [Display omitted] • A partial transient liquid phase bonding process for misoriented single crystal superalloys is proposed. • The joints are free of boron/silicon-rich low-melting eutectics or compounds commonly found in brazed joints, while the presence of the polycrystalline zone prevents the formation of penetrating grain boundary in joints obtained by transient liquid phase bonding process. • The tensile strength of the joints at 980 °C reach 682 MPa, which is 92% of the base metal. • The partial transient liquid phase bonding process achieved rapid isothermal solidification with the help of the short-distance and large-area diffusion mechanism. [ABSTRACT FROM AUTHOR]

The influence of high intensity mixing of graphene platelets with stainless steel particles in the scope of additive manufacturing is investigated. Therefore, 0.75 vol% graphene platelets were coated onto conventional stainless steel powder as a model material, resulting in very homogenously distributed graphene layers. The specific energy input during mixing was found to be the main factor for increasing the flowability and decreasing the reflectivity of the powder. Furthermore, the resulting surface roughness of the coated powders could be correlated with a theoretical consideration of van der Waals forces. In this way, the mixing process can be controlled regarding its specific energy input to achieve tailored powders for the application in PBF-LB/M. Cubic parts were produced with different laser parameters and analysed. As a result, the admixing of graphene at lower specific energies resulted in a wider process window and parts with a relative density of 99.99% were achieved. [Display omitted] • The particles' surface roughness is adjustable by high intensity mixing. • The specific energy while mixing defines the flowability and reflectivity of powder. • Tailored particles for PBF with increased bulk densities and heat diffusivities. • Enhanced mechanical properties of manufactured parts for tailored particles. [ABSTRACT FROM AUTHOR]

Thermal barrier coatings are used to protect hot section parts of gas turbine engines. These coatings are subject to corrosion due to impurity elements in the fuel and dust absorbed from the atmosphere into the engine. The rough and porous surface nature of plasma-sprayed coatings facilitates the penetration of these factors into the coating. Coatings are damaged prematurely as a result of corrosion. In this study, nano-structure YSZ, YSZ + Al 2 O 3 , YSZ + TiO 2 , and YSZ + Al 2 O 3 + TiO 2 coatings were deposited on plasma sprayed YSZ coating by electrophoretic deposition method. Hot corrosion and CMAS resistance were investigated. The coatings were characterized by SEM, XRD, AFM, and microhardness before corrosion tests. The changes in the coatings after corrosion tests were characterized by SEM and XRD. The penetration behavior of corrosive factors was examined by elemental mapping with EDS. Nanostructure coatings deposited on APS YSZ made the surfaces of as-sprayed coatings more stable. The ability of these nanolayers to prevent pure penetration into coatings during hot corrosion and CMAS is limited. However, the Al 2 O 3 + TiO 2 -doped nanostructure YSZ reduced the bond-layer oxidation. In addition, the addition of Al 2 O 3 + TiO 2 to the EPD deposited layer also reduced the tetragonal-monoclinic phase transformation that occurred in YSZ as a result of corrosion. Al 2 O 3 and TiO 2 additives alone are not effective in improving the corrosion behavior of coatings. Nanostructured coatings deposited with the EPD technique can help protect plasma-sprayed thermal barrier coatings against corrosion. • Approximately 20 μm thick nanostructured coatings were successfully deposited on plasma-sprayed YSZ using the EPD method • Surface porosities in plasma sprayed coating are eliminated. Surface roughness has been reduced. • In hot corrosion and CMAS corrosion tests, the least pure penetration was obtained in Al 2 O 3 +TiO 2 doped nano YSZ. • Nanostructured coatings deposited with the EPD technique have great potential in protecting APS TBC against corrosion [ABSTRACT FROM AUTHOR]

The growing concern on energy savings in buildings, particularly related with cooling needs, has led to the search of new constructive solutions. Frequently, darker colour coatings are used in buildings for aesthetics purposes. However, such coatings have low reflectance, absorbing a large portion of the solar radiation. The associated heat gains enhance the building cooling demand and may reduce the service life of renderings owing to the increased thermal stresses in comparison to light colour coatings. The aim of this study was to assess the influence of size (30–5000 nm), optical band gap energy and concentration (0–20%) of TiO 2 nanoparticles in a conventional black colourant for building applications. We confirm that the use of TiO 2 nanoparticles increases the reflectance of the colourant and demonstrate that 50 nm is the most adequate nanoparticle size for reflectance enhancement. Furthermore, the colourimetric parameters are also affected by TiO 2 incorporation, with the colour difference becoming increasingly noticeable to the human eye with increasing TiO 2 concentration. Such results can lead to new formulations of solar reflective coatings are able to reduce the overall cooling load, particularly in warm climates with high cooling demands. • We explore the effect of TiO 2 nanoparticle size, band gap and concentration in a black colourant on its optical performance. • We demonstrate that the reflective performance of these TiO 2 -mixed colourant is significantly improved in the NIR region. • Such study can lead to new formulations of solar reflective coatings able to reduce. [ABSTRACT FROM AUTHOR]

Hydrometallurgical unit operations are typically used to recover palladium (Pd) from its ores and secondary resources with high selectivity owing to their low energy consumption, cost effectiveness, and volume flexibility. Herein, diluted HNO 3 solutions with added nitrate salts were used to dissolve Pd powders. Moreover, solutions of nitrates with same valency cations (such as HNO 3 , LiNO 3 , NaNO 3 , KNO 3 , CsNO 3 , and NH 4 NO 3) and same period cations (such as NaNO 3 , Mg(NO 3) 2 , and Al(NO 3) 3) were used to reveal the involved beneficial effects of the nitrates on the Pd dissolution in an environment friendly way with low acidity of the solutions. Among all added alkali metal nitrates, LiNO 3 resulted in the highest Pd dissolution efficiency, which was attributed to the higher dissociation constant of LiNO 3 , resulting in a higher concentration of free nitrate and hence a higher oxidation potential of the overall system. The dissolution process was systematically investigated to determine the optimal temperature (353 K), LiNO 3 and HNO 3 concentrations (6 and 1 mol L−1, respectively), stirring speed (500 rpm), and reaction time (5 h). These optimal conditions yielded a dissolution efficiency of 99.6%. Notably, as the reaction proceeded, the Pd powder surfaces corroded to form numerous holes, indicating that internal diffusion control also affected Pd dissolution. • A novel HNO 3 –nitrate system is used for Pd dissolution. • Low acid consumption and more environmentally friendly dissolution system. • Catalytic effect of alkali metal nitrates on Pd dissolution. [ABSTRACT FROM AUTHOR]

A certified reference material (CRM) for major and trace elements in black tea powder has been developed at National Centre for Compositional Characterization of Materials/Bhabha Atomic Research Centre (BARC), Hyderabad. The study describes an acid assisted microwave digestion of tea powder followed by quantitation of K, Ca, P, Mg, Mn, Al, Fe, Ba, Zn, Cu and Sr by ICP-AES; Pb, Cd by GFAAS and As, Hg by AFS in the digests. The method was validated in terms of selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), trueness, precision, traceability, ruggedness and combined uncertainty using a CRM of tea powder (NMIJ CRM 7505-a) and spike recovery studies. The obtained values of LOQ ranged from 0.018 % m/m for Ca to 0.35mg kg−1 for Hg. Precision of the method was found to be <5% for all the analytes (K, Ca, P, Mg, Mn, Al, Fe, Ba, Zn, Cu, Sr, Cd and Hg) excepting for Pb and As (6.5 % at 95% confidence level). The obtained LOQ values, trueness and precision established that the validated method could be used for the characterization of candidate tea CRM during homogeneity and stability studies. Candidate tea CRM (∼3.6 Kg) was processed (which included spiking, drying grinding and sieving) and its homogeneity was assessed at various levels with respect to all 15 property values. The assignment of the property values for each element was carried out after an interlaboratory comparison exercise (ILCE), where 11 laboratories from various government and private sectors participated. A total of four techniques inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma atomic emission spectrometry (ICP-AES), graphite-furnace atomic-absorption spectrometry (GFAAS) and atomic-fluorescence spectrometry (AFS) were used during ILCE. Property values were assigned for 14 elements (K, Ca, P, Mg, Mn, Al, Fe, Ba, Zn, Cu, Sr, Pb, Cd, and Hg) along with combined uncertainties. The concentration with expanded uncertainties of the property values were between 0.458 ± 0.025 for Ca (% m/m) to 0.60 ± 0.084 mg kg−1 for Hg. Long-term stability studies suggested that the produced tea CRM is stable at storage temperature (4 °C) for the last two years, whereas, short-term stability studies (at temperatures 4, 25 and 40 °C) established its transportation stability at tested temperatures for a period of three weeks. Preparation and certification of tea CRM (BARC-D3201) was carried out in accordance with ISO Guides 17034 and 35. • Development and validation of a method for elemental analysis in tea powder. • The developed method was used for the characterization of candidate tea CRM. • Candidate tea CRM was found to be homogenous with respect to tested property values. • BARC -D3201 was produced and certified for fourteen property values after ILCE. • BARC-D3201 was found to be stable with respect to certified property values. [ABSTRACT FROM AUTHOR]

The ethanol extract from lotus seed peel powder (EEL) were characterized, and its antioxidant and sausage preservation effects were investigated in this study. Chemical composition, UV and FTIR spectra of EEL, 70% ethanol-soluble matter (70-DF), and precipitate (70-PF) showed similar trends to some extent, indicating their similar chemical composition. Then, their antioxidant potentials were confirmed that EEL exhibited stronger DPPH· scavenging capacity, FRAP, and lipid peroxidation inhibitory activities than those of 70-DF and 70-PF. Correlation analysis also indicated phenolics as the main antioxidant components of EEL. Hence, catechin, epicatechin, rutin, phlorizin, and gallic acid were identified as the dominant phenolics of EEL. Throughout the chopping, roasting, cooking and pasteurization processes, EEL could protect the color, maintain the pH value, and decline the total volatile base nitrogen (TVB-N) and thiobarbituric acid reactive substances (TBARS) values of sausages. Following 18 days of storage at 25 °C, supplementation with EEL reduced the TVB-N and TBARS values of sausages, while pH value showed an opposite trend. The present study found that EEL could prolong the shelf life of sausages via inhibiting the oxidation of lipids and proteins, which would promote the utilization of lotus seed peel powder as a substitute for nitrites to preserve meat products. [Display omitted] • UV and FTIR spectra of EEL, 70-DF, and 70-PF showed a similar trend to some extent. • EEL had stronger DPPH· scavenging, FRAP, and lipid peroxidation inhibition than 70-DF and 70-PF. • Catechin, epicatechin, rutin, phlorizin, and gallic acid were the dominant phenolics of EEL. • EEL could be used as a substitute for nitrites to preserve sausages during processing and storage. [ABSTRACT FROM AUTHOR]

In this paper, metallic powder coatings (MPC) were investigated as base powder coatings incorporating metallic flakes, providing finishes with a sparkly metallic effect. While MPC offers environmental advantages over liquid coatings by eliminating the usage of solvents, it presents challenges in achieving an intensified and stable metallic effect required by high-end products. This is primarily due to the limitations of the friction-based bonding technique, such as non-selective heating, employed in the current commercial production of MPC. To address this challenge, a microwave-based bonding method was developed that utilizes microwave energy as the heating source instead of stirring friction. This innovative approach leverages the selective heating properties of microwaves to produce qualified MPCs suitable for high-end products. Compared to the current friction-based method with a heating rate of approximately 4 ∘ C/min, microwave heating achieved a significantly faster heating rate of approximately 16 ∘ C/min, owing to the interface polarization effect. The microwave heating engendered a heightened efficacy in forging bonds between coating particles and Al flakes. As a consequence, in scenarios where equal weight percent of Al flakes was introduced, the microwave-treated specimens evinced a stronger metallic effect and enhanced stability compared to friction-heated ones. Furthermore, three-dimensional images of the Al flakes in the coating confirmed that microwave-heated films manifested an elevated flip-flop effect. Tribocorrosion test outcomes underscored that microwave-heated films exhibited higher open circuit potentials (OCP), indicating superior corrosion resistance, alongside better wear resistance compared to friction-heated ones. The microwave-based method obtained stronger and more stable MPCs with better corrosion and wear resistance, showing the promising potential for the expansion of MPC applications into the domain of high-end commodities. [Display omitted] • Innovatively using 2.45 GHz microwaves for heating/bonding metallic powder coatings. • Interface polarization of microwaves greatly improved bonding efficiency. • Microwave heating enhanced film stability and intensity significantly. • Microwave heating improved film wear/corrosion resistance vs. friction heating. [ABSTRACT FROM AUTHOR]

• Some silicide materials are found out as insert materials for the fabrication of W/CFC blocks. WSi 2 do not exceed but are the same level as insert material as that of SiC + additives. • Zr and V behave as insert materials for W/CFC bonding, but the thermal stability of specimens is not enough. • The bonding strength near edge of an expected size of mono-block is not enough. It needs to be fabricated as a larger size block with 40 MPa of pressure and removed its near-edge parts. The construction of a satellite tokamak, JT-60SA, was completed in 2020. JT-60SA is expected to contribute the research of ITER and developments for DEMO. JT-60SA employs carbon and carbon fiber strengthened carbon (CFC) composites divertors. The divertors will be set on an actively cooled cassette and be remotely handled because of human access restriction into the vacuum vessel due to the radioactivation caused by repeated deuterium plasma operations. An important mission of JT-60SA is high-β steady state plasma research, and during the mission, the use of carbon divertors will be continued. The possibility of metal wall experiments after the complete of high-β steady state plasma research is under discussion. Then the use of remote handled divertor cassette will be a condition, therefore, high performance and appropriate weight divertors are convenient for the operation. One idea is to use clad plates of tungsten and CFC. In previous researches revealed that a sinter bonding method using an insert material of SiC powders + additives was able to join W and CFC. But the research accidentally found out the insert material without explore of the other materials and the size of specimens was small. In present research, some candidates for the insert material were investigated and also the uniformity of strength on a W/CFC block of the expected size were evaluated. [ABSTRACT FROM AUTHOR]

The addition of small quantities of aluminum oxide (Al2O3) to 8 mol% yttria‐stabilized zirconia (8YSZ) benefits conventional sintering by acting as a sintering aid and altering grain growth behavior. However, it is uncertain if these benefits observed during conventional sintering extend to flash sintering. In this work, nanoscale films of Al2O3 are deposited on 8YSZ powders by particle atomic layer deposition (ALD). The ALD‐coated powders were flash sintered using voltage‐to‐current control and current rate experiments. The sintering behavior, microstructural evolution, and ionic conductivities were characterized. The addition of Al2O3 films changed the conductivity of the starting powder, effectively moving the flash onset temperature. The grain size of the samples flashed with current rate experiments was ~65% smaller than that of conventionally sintered samples. Measurement of grain size and estimates of sample density as a function of temperature during flash sintering showed that small quantities of Al2O3 can enhance grain growth and sintering of 8YSZ. This suggests that Al2O3 dissolves into the 8YSZ grain boundaries during flash sintering to form complexions that enhance the diffusion of species controlling these processes. [ABSTRACT FROM AUTHOR]

PM10 concentration and its elemental content were measured inside a university classroom where painting and sketching activities took place. The primary goal was to investigate the impact of these activities to (1) indoor PM10 concentrations, (2) identify PM10 levels in the presence/absence of the activities and (3) investigate the corresponding impact on its elemental content. As such, indoor online measurements and 24-h gravimetric measurements took place at short-term fixed periods. Outdoor PM10 concentrations were also available. It was found that PM10 levels were substantially increased during the occupied hours with average PM10 during activity ranged between 19 and 171 μg/m3, whereas during background periods it ranged between 12 and 66 μg/m3. Moreover, indoor concentrations during the activity were usually higher compared to outdoor levels, but the opposite behavior was found for background periods. Regarding the elemental content, positive correlations of heavy metals (Cu, Zn, Pb, Ba) found predominantly in the coarser fraction were associated with the use of painting powders. On the other hand, metals like Cr, Mn, Fe and Ni were primarily associated with anthropogenic sources, while the crustal origin of Ti, Mg and Al dominated indoors for particles > 1 μm. Other correlations between elements in the submicron fraction suggested origin from soil and anthropogenic sources as well as aged painting-originated particles. In summary, the present study demonstrated the significant impact of painting/sketching activities to indoor PM10 levels. Direct emissions from the use of powders as well as resuspension activities of the occupants were identified as the major indoor sources that provoked elevated concentrations. [ABSTRACT FROM AUTHOR]

Pneumatic conveying is one of the industrial processes that give the most electrical charge to divided solids. This electrical charge is generally a nuisance that can, for example, influence the flowability, create discharges or even explosions in the ducts. In order to counteract these tribocharging phenomena, which are not well apprehended, several authors designed and implemented different measurement devices for the measurement of powder tribocharging in pneumatic conveying. In this article, we present an overview of four such devices. The first one has been based on a loop operation principle using Teflon particles convoyed with azote. According to the process of powder coating, a second was elaborated. A third was developed to confront several parameters that influence tribocharging in pneumatic conveying. The latest apparatuses presented here have been improved to carry out more reliable tests. [ABSTRACT FROM AUTHOR]

To promote the dissemination of Positive Selection (PS) technology for quality seed yam production, this study was undertaken to provide empirical evidence and to examine differences in the Total Factor Productivity resulting from the use of PS technology. Through multistage sampling, 368 CAY-Seed beneficiaries from Ghana and Nigeria were sampled. Results indicate that productivity of PS technology was 0.758 as compared to 0.700 for non-use of PS. Furthermore, the use of PS also led to a reduction in technology gap by 2.3%. The most important factors of seed yam productivity were: land, seed, labour, chemical and neem leaf powder application with sex, experience, education, cropping system and extension as the inefficiency determinants. It is therefore recommended that the PS technology should be widely disseminated with policies to reduce inefficiency. [ABSTRACT FROM AUTHOR]

Copyright of Romanian Journal of Materials / Revista Romana de Materiale is the property of Foundation for Materials Science & Engineering Serban Solacolu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, three different electrostatic powder coating wastes of thermoset structure were used as fillers for low-density polyethylene (LDPE). The mechanical, thermal, and morphological properties of these composites materials are reported. The thermoset powder coating wastes were hydrolyzed using water and alcohol, and then 10%, 20%, and 30% by weight of the deactivated wastes were mixed with LDPE, first in a mechanical dry mixer, and subsequently homogenized by melt compounding in an extruder at about 160 °C. Standard tensile test bars and plate-shaped samples were produced from these homogeneous compounds by injection molding. The effects of adding hydrolyzed powder coating wastes on the properties of LDPE were determined by mechanical, thermal, and morphological tests. Tensile strength and perforation threshold of the sample filled with powder coating wastes decreased to some extent compared to un-filled sample. However, an increase in izod impact and bending strengths has been observed. The results of this investigation demonstrate that powder coating wastes with thermoset structure can be used as fillers in LDPE.

This team of authors presents the development of an algorithm and its practical application in the software for solving the problems of automatizing the calculation of principal characteristics for powder painting chambers. The algorithm enables a developer to consider several design solutions to select an optimal variant with consideration for the initial data. The application of this algorithm and the software on its basis is illustrated with the design works of NPO Lakokraspokrytie. [ABSTRACT FROM AUTHOR]

In order to get good properties of nickel-plated aluminum powder, the nickel-plated aluminum powder was prepared by displacement reaction on the surface of the aluminum powder. The morphology and composition of the nickel-plated aluminum powder was characterized by scanning electron microscope, energy dispersion spectrometer and X-ray diffraction spectrometer. The apparent density, the tap density and pressure of the nickel-plated aluminum powder were tested by an apparent density tester, at ap density tester and a DC resistance tester. The results showed that when the single displacement temperature was 70°C and the concentration of nickel salt and reductant was 60g/L, the nickel-plated aluminum powder was coated completely and closely. The nickel content of the nickel-plated aluminum powder was 75.23%, the apparent density and tap density were 2.179g/cm³ and 2.547g/cm³, respectively. The compaction resistivity could reach 10.6mΩ·cm. [ABSTRACT FROM AUTHOR]

Low-dimensional materials could improve the interface strength between the epoxy resin and carbon fibers (CFs) in the composites. Four type of low-dimensional powders were employed to functionalize the CFs/epoxy interface, and their reinforcement efficiency were compared by performing CF bundle pull out test. Two kinds of processing methods were adopted to introduce low-dimensional powders, one is coating powders onto the CF surfaces, and the other is adding powders in epoxy resin. It is shown that adding these nano-fillers into the matrix and coating them onto the CF surface resulted in a marked improvement in the interface adhesion. Moreover, the cohesive finite element method was employed to unveil the effect of some uncertain parameters on the measured results. [ABSTRACT FROM AUTHOR]

Sands are naturally hydrophilic granular materials, yet, rendering them hydrophobic could lend them to a wide range of geotechnical applications. This study describes a powder-coating procedure performed after chemically modifying the surfaces of coarse, medium and fine sands and examines its effect on their hydrophobicity. The purpose is to render these granular materials more hydrophobic than what is conventionally achieved by chemical methods using a simple technique. The procedure consists of first silanising both the sands and silica powder at a similar concentration by means of an organosilane to modify their surface chemistry, then the silica powder is adhered to the sands at a mass mixing ratio to alter their hydrophobicity. Irrespective of the concentrations and mixing ratios, the powder-coating procedure enhances the hydrophobicity of sands in comparison to the sole use of the chemical method. Changes in the morphology of the sand grains, such as their particle size, particle shape and surface roughness, resulting from the powder-coating procedure are examined by means of dynamic image analysis, profilometry and scanning electron microscopy. The effects of surface chemistry, surface roughness and air on the hydrophobicity of the sands are discussed based on theoretical wetting models to analyse the experimental results. [ABSTRACT FROM AUTHOR]

Button mushrooms (Agaricus bisporus) were coated by dissolving four different organic coating material viz. apple peel powder (1.0 to 1.4% wt/vol), carboxymethyl cellulose (1.2 to 1.8% wt/vol), tartaric acid (0.375%), and glycerol monostearate (1%) in distilled water and dipping the mushroom in coating solution for 45 to 75 s. Experiments were conducted using response surface methodology and the coated as well as uncoated samples were stored at ambient and refrigerated conditions. Various quality parameters of button mushroom were measured. Results indicated that the mushroom coated at optimum condition (apple peel powder 1.17% wt/vol, carboxymethyl cellulose 1.8%, and dipping time 75 s) maintained high level of quality parameters and were used to develop the organic coating powder. The use of coating powder for coating under ambient and refrigerated condition has the potential to maintain mushroom quality and prolong its postharvest shelf life up to 5 and 9 days, respectively. Practical applications: The efficacy of developed organic coating powder tested on button mushroom (Agaricus bisporus) shows some prominent practical application for fresh produce. From the analysis and interpretation of the experimental results it was found that the developed organic coating powder was effectively increased the shelf life of button mushroom and also maintained its quality characteristics during storage, and hence, can be a promising as an edible coating for practical use as well as in commercial postharvest applications to enhance the storage life of button mushroom and other fresh produce. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the counter body effect on the wear behavior of TiO2-45 Cr2O3 coating. The commercial TiO2-45 Cr2O3 coating powder was deposited onto the surface of the AISI 316 L substrate using the APS method. Dry sliding wear tests were performed with Al2O3 and WC-Co counter body balls under different loads (5 N, 10 N, and 15 N) and reciprocating frequencies (1 Hz, 2 Hz, and 3 Hz). The COF values obtained from the Al2O3 ball were found to be higher than that of the WC-Co ball. In general, increasing load and sliding speed caused higher wear volume values for both counter body balls. When using Al2O3 ball under the 5 N load, a higher amount of wear debris and crack formation was observed, whereas, for higher loads, a larger plastic deformation zone which has lots of pitting and spalling was determined. As for the WC-Co ball, swelling-induced spallation and delamination were recorded as the effective wear mechanisms as well as the plastic deformation. [ABSTRACT FROM AUTHOR]

Three urethane methacrylates, one monofunctional derivative and two di-functional derivatives with different chain lengths were used as reactive diluents in UV-curable polyester powder coatings. Each reactive diluent was formulated with a methacrylated polyester oligomer using conventional melt extrusion techniques. The effect of these compounds on zero-shear melt viscosity was investigated. Incorporation of 10 wt% reactive diluent effectively reduced the viscosity by an order of magnitude. After UV-curing, the viscoelastic, thermal, and mechanical properties of the films were characterized using dynamic mechanical analysis, differential scanning calorimetry, thermogravimetric analysis, and tensile tests. The type and concentration of reactive diluent that was used directly influenced the glass transition temperature, modulus, % elongation-at-break, and crosslink density. Of the two di-functional reactive diluents that were used, the derivative that contained a shorter methylene spacer group resulted in more heterogeneous crosslinked networks. [ABSTRACT FROM AUTHOR]

A series of nanocomposite (NC) powders and coatings of ZnO–GeO2–TeO2:xSm3+ glass and Y3Al5O12:Ce3+ nanoparticles (YAG:Ce) are fabricated. Samarium ions concentration of the glass phosphor is varied with x values of 0.3, 1.0, 3.0, and 5.0 mol%. The powder batches are prepared with a 95/5 mass ratio of glass/YAG:Ce and uniaxially pressed to obtain powder pellets that are heat‐treated at 350 °C. Morphology and structural characterization are conducted through X‐ray diffraction analysis, scanning electron microscopy, and Raman spectroscopy. The photoluminescence properties of NCs are investigated under different wavelengths of 340, 403, and 460 nm, showing a global emission tonality in the reddish‐orange and yellowish‐green region according to the estimated CIE 1931 chromaticity coordinates. Also, NC coatings soda–lime glass slides are fabricated, and their photoluminescence is characterized using an UV light‐emitting chip (≈365 nm) and a blue light‐emitting chip (≈460 nm). The global emission under UV and blue light from the light‐emitting diode (LED) chips of the NC coatings shows a color tunability in the warm white light and yellowish‐green region. [ABSTRACT FROM AUTHOR]

Limited number of studies investigated the effects of Electrostatic powder paints (EPP) on human health. We investigated the effects of EPP exposure on lung function, exercise capacity, and quality of life, and the factors determining exercise capacity in EPP workers. Fifty-four male EPP workers and 54 age-matched healthy male individuals (control group) were included. Lung function and respiratory muscle strength were measured. The lower limit of normal (LLN) cut-points for FEV1 and FEV1/FVC were calculated. An EPT was used to evaluate bronchial hyperactivity. The handgrip and quadriceps muscle strength were evaluated using a hand-held dynamometer. An ISWT was used to determine exercise capacity. The physical activity level was questioned using the IPAQ. The SGRQ and NHP were used to assessing respiratory specific and general quality of life, respectively. Duration of work, FEV1, MIP, handgrip strength, and ISWT distance were significantly lower, and the change in FEV1 after EPT and %HRmax were significantly higher in the EPP group compared to the control group (p < 0.05). There were no subjects with a < LLN for FEV1 and FEV1/FVC in both groups. In the EPP group, ISWT distance was significantly related to age, height, duration of work, FEV1, change in FEV1 after EPT, MIP, MEP, handgrip strength, IPAQ, SGRQ, and NHP total scores (p < 0.05). The change in FEV1 after EPT, MIP, and duration of work explained % 62 of the variance in the ISWT distance (p < 0.001). Changes in lung function based on LLN for the FEV1 and FEV1/FVC were not clinically relevant in EPP workers. Exercise capacity is impaired in EPP workers. Degree of exercise-induced bronchospasm, inspiratory muscle strength, and duration of work are the determinants of exercise capacity in EPP workers. [ABSTRACT FROM AUTHOR]

Ability to predict the porosity, and its reduction after nano-silica dry coating, based on the Bond number and cohesion force estimated via multi-asperity contact model was examined for twenty different pharmaceutical powders. A new model for first order estimates of bulk density improvements after dry coating was found to be reasonably predictive despite variations in size (10–225 μm), particle size distribution, aspect ratios (1–3.5), material density, and dispersive surface energy. For the porosity prediction model based on Bond numbers, Microcrystalline Cellulose (MCC) excipients were outliers, regardless of size (20–200 μm). Analysis of their shape, surface morphology and specific surface areas (SSA), indicated that compared to other powders, MCCs had the highest SSA compared to equivalent spheres and high macro-roughness, while having high aspect ratios. This unique characteristic made them effectively more cohesive leading to their poor packing independent of their size, which is in line with previous simulations. Unlabelled Image • A new empirical model predicts increase in bulk density (10–90%) after dry coating. • Bond number model well-predicted porosity of a variety of pharmaceutical powders. • MCC were outliers, due to high relative SSA from non-sphericity and macro-roughness. • MCC behavior mimicked prior DEM results for cohesive, high aspect ratio particles. • Using entire PSD vs d 50 alone or asperity adjustments did not improve prediction. [ABSTRACT FROM AUTHOR]

In this study, four excessive worn brake rotors of a light commercial vehicle are coated using different thickness, methods and powder coatings. Coated rotors (R 1 , R 2 , R 3 and R 4) compared with OEM brake rotor (R 0) in terms of friction coefficient (μ) and braking noise. Three braking test procedures (bedding, hot judder I and II) are applied to five rotors using inertia brake dynamometer. Results in bedding testing procedures showed that R 0 rotor provided higher brake noise and higher μ compared with coated rotors. In hot judder I testing procedures, R 4 rotor provided higher μ and higher brake noise compared with the other coated rotors and R 0. Also, in hot judder II testing procedures, R 2 rotor provided higher μ compared with the other rotors, R 0 provided higher brake noise compared with the other coated rotors. In addition, based on experimental data, noise levels are estimated by multiple regression method with dummy variables. [ABSTRACT FROM AUTHOR]