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Designing efficient Ruthenium-based catalysts as practical anodes is of critical importance in proton exchange membrane water electrolysis. Here, we develop a self-assembly technique to synthesize 1 nm-thick rutile-structured high-entropy oxides (RuIrFeCoCrO2) from naked metal ions assembly and oxidation at air-molten salt interface. The RuIrFeCoCrO2 requires an overpotential of 185 mV at 10 m A cm−2 and maintains the high activity for over 1000 h in an acidic electrolyte via the adsorption evolution mechanism. We discuss the role of each element in the RuIrFeCoCrO2 and find that the Cr, Co, and Ir sites contribute to the catalytic activity, while the Cr atoms weaken the Ru-O bond covalency and improves the catalyst stability. The assembled proton exchange membrane electrolyzer operates stably for more than 600 h at a large current of 1 A cm−2. The naked ion assembly demonstrated in this work may provide an effective pathway for the controlled synthesis of a diversity of high-entropy materials. Designing efficient ruthenium-based catalysts as practical anodes is important for proton exchange membrane electrolysis. Here, the authors report a self-assembly technique to synthesize atomically thin high-entropy oxides from the assembly of naked metal ions for hydrogen generation. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the sound absorption efficiency of plywood-carbon fiber composite materials and evaluate their potential as acoustic panels. In this work, plywood and plywood-carbon fiber composite materials were produced using Uludağ fir (Abies nordmanniana subsp. bornmülleriana Mattf.) peeling veneer, woven carbon fiber, and polyvinyl acetate (PVAc) adhesive. Three experimental groups and a control group were created. The materials from plywoodcarbon fiber composite were manufactured in three different designs to form experimental groups. The sound absorption coefficients of the plywood and the composite materials were tested via the impedance tube method, according to ASTM standard E1050-98 (2006). Attention was paid to the acoustic behavior at low (bass) frequencies (63 Hz to 250 Hz), mid frequencies (315 Hz to 1600 Hz), and high (treble) frequencies (2000 Hz to 6300 Hz). It was determined that the plywood-carbon fiber composite materials could reflect or transmit sound waves at low (bass) frequencies, while significantly absorbing sound waves at high (treble) frequencies. It can be suggested that plywood-carbon fiber composite materials could be used as sound absorbing acoustic panels. [ABSTRACT FROM AUTHOR]

Metal-free catalysts are made by the elements with infinite reserve in nature and, therefore, show the potential for large-scale applications in energy devices including metal–air batteries. The construction of metal–air batteries prefers using self-supporting catalysts with favorable activity as well as fast kinetics. However, it is challenging due to the limited electropositivity of metal-free catalysts for O–O bond formation in oxygen evolution reaction (OER), scaling relationship restrictions between OER and oxygen reduction reaction, and difficulty in porosity construction on the monolith electrode surface. In this contribution, through developing a facile methodology of quenching high-temperature carbon clothes in liquid nitrogen, a self-supported carbon cloth with bifunctional active graphene skin and fast kinetics is well constructed to serve as the air cathode in metal–air batteries. Regulated oxygen species and three-dimensionally hierarchical porosity are well constructed on the carbon fiber surfaces, contributing high intrinsic activity and prominently enhanced kinetics, which leads to favorable performances in aqueous as well as flexible rechargeable zinc–air batteries. The work proposed a promising strategy in the rational design and smart synthesis of fast-kinetic monolith electrodes, which refreshes concepts and strategies of advanced material fabrication, and also bridges material science and practical energy devices. [ABSTRACT FROM AUTHOR]

To address the urgent demand for sustainable battery manufacturing, this review contrasts traditional wet process with emerging dry electrode technologies. Dry process stands out because of its reduced energy and environmental footprint, offering considerable economic benefits and facilitating the production of high‐energy‐density electrodes. We spotlight technological innovations that exemplify the paradigm shift towards eco‐friendliness and cost‐efficiency. This review synthesizes the latest developments in dry electrode production, comparing the techniques with conventional methods, and outlines future research for further optimization toward a higher technology readiness level. We suggest that the evolution of battery manufacturing hinges on the synergy between process innovation and materials science, which is crucial for meeting the dual goals of environmental sustainability and economic practicality. [ABSTRACT FROM AUTHOR]

Copyright of Erzincan University Journal of Science & Technology is the property of Erzincan Binali Yildirim Universitesi 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.)

Over the past several decades, there has been a significant surge in interest regarding the use of organic–inorganic hybrid polymers and nanocomposite membranes. The reasons for this are improved attributes, reduced costs, and the additional stability the influence membrane provides. This Review outlines the various techniques and methodologies used to prepare Nafion and its composites, delineating the promising benefits of the electrospinning process. Electrospinning has emerged as a versatile and promising technique for fabricating nanofibers with unique properties and wide-ranging applications. This study explores the electrospinning of Nafion, a perfluorosulfonic acid polymer widely known for its exceptional proton conductivity and chemical stability, into nanofibrous structures, unlocking new possibilities yet unknown features of its inherent properties. The morphology and chemical structure of the resulting nanofibers is analyzed. A thorough bibliographic analysis of electrospun Nafion was presented using the PRISMA approach for methodically presenting the report. Network visualization of connected authors and categorizing application-specific publications are also discussed. Moreover, the electrospinning parameters and blends are systematically investigated to optimize the production of Nafion nanofibers for various applications in fuel cells, water treatment, actuators, sensors, and energy harvesting. The challenges involved in electrospinning Nafion, Nafion nanocomposites, and their variants are also presented, with a discussion delineating the future scope. This work concludes by emphasizing the interdisciplinary character of the Nafion polymer and its composites, connecting materials science and the intricate issues presented by various sectors. [ABSTRACT FROM AUTHOR]

A novel family of multifunctional nanomaterials called MXenes is quickly evolving, and it has potential applications that are comparable to those of graphene. This article provides a current explanation of the design and performance assessment of MXene-based membranes. The production of MXenes nanosheets are first described, with an emphasis on exfoliation, dispersion stability, and processability, which are essential elements for membrane construction. Further, critical discussion is also given to MXenes potential applications in Vacuum assisted filtration, casting method, Hot press method, electrospinning and electrochemical deposition and layer-by-layer assembly for the creation of MXene and MXene derived nanocomposite membranes. Additionally, the discussion is carried forward to give an insight to the modification methods for the construction of MXene-based membrane are described in the literature, including pure or intercalated nanomaterials, surface modifiers and miscellaneous two-dimensional nanomaterials. Furthermore, the review article highlights the potential utilization of MXene and MXene based membranes in separation and purification processes including removal of small organic molecules, heavy metals, oil-water separation and desalination. Finally, the perspective use of MXenes strong catalytic activity and electrical conductivity for specialized applications that are difficult for other nanomaterials to accomplish are discussed in conclusion and future prospectus section of the manuscript. Overall, important information is given to help the communities of materials science and membranes to better understand the potential of MXenes for creating cutting-edge separation and purification membranes. [Display omitted] • Innovative MXene-Derived Functional Hybrid Nanostructures Enhancing Water Purification Membranes. • Exploring Advanced Synthetic Approaches for MXene Nanosheets and MXene-Derived Membranes. • Tailoring MXene-Based Membranes: Insights into Effective Modification Techniques. • Exploring Boundaries and Charting Future Directions in MXene-Based Water Purification Membranes. [ABSTRACT FROM AUTHOR]

The microstructure, mechanical and dry-sliding tribological properties of TiAl-based composites with 20 and 40 vol% in situ formed TiAlC, produced by hot press sintering process, are investigated. The microstructural characterization reveals that TiAlC phase is in the form of spherical particles and large blocks, and the quantity of the blocks increases with TiAlC content. This difference in the morphology and distribution of the TiAlC phase leads to the discrepancy of the wear resistance of the composites. In contrast to the Ti-46Al-2Cr-2Nb intermetallics, the dry-sliding wear resistance of the TiAl/TiAlC composites first declines slightly and then enhances with the TiAlC content. Furthermore, the TiAl/40 % TiAlC composite shows low wear rate at higher sliding speed. [ABSTRACT FROM AUTHOR]

Carbon fabric-reinforced polymer (CFRP) composites have replaced most aluminum and ferrous alloys in aerospace construction owing to their attractive high strength-to-weight ratio. CFRPs used in aircraft should have electromagnetic shielding ability in addition to structural properties. Hence, the study of Electromagnetic (EM) wave shielding by hybrid CFRPs is an important topic of research. In this article, we summarize research advancements for enhancing the EM wave shielding of CFRP composites in the X-band frequency range. This study focuses on the manufacturing and performance of carbon-fabric-based composites with metals, metal oxides, and carbon-based fillers. The factors influencing the EM wave shielding ability of the CFRP composites are also discussed. The EM wave shielding of Carbon fibers (CF) was remarkably improved by coating, electroless plating, and synthesizing nanoparticles on the carbon fiber surface. It was found that the carbonious fillers and metal nanofillers such as Nickel (Ni), Iron (Fe), and Silver (Ag)-loaded multilayer CFRP composites showed better absorption modes of EM wave shielding with good structural properties. Owing to the Ag nanowire coating on the CFs, the shielding effectiveness was drastically improved. However, in addition to the type of filler, the structural properties are also influenced by the manufacturing method and type of composite. In the case of laminated composites, the absorption-laminated EM shielding is influenced by the architecture of the plys and the type and number of interplay in the composite construction. In addition, the techniques adopted for the synthesis of nanoparticles and dispersion in composites for effective EM shielding are challenging tasks. [ABSTRACT FROM AUTHOR]

The melting phenomenon in metal–organic frameworks (MOFs) has been recognised as one of the fourth generation MOF paradigm behaviours. Molten MOFs have high processibility for producing mechanically robust glassy MOF macrostructures, and they also offer highly tunable interfacial characteristics when combined with other types of functional materials, such as crystalline MOFs, inorganic glass and metal halide perovskites. As a result, MOF glass composites have emerged as a family of functional materials with dynamic properties and hierarchical structural control. These nanocomposites allow for sophisticated materials science studies as well as the fabrication of next-generation separation, catalysis, optical, and biomedical devices. Here, we review the approaches for designing, fabricating, and characterising MOF glass composites. We determine the key application opportunities enabled by these composites and explore the remaining hurdles, such as improving thermal and chemical compatibility, regulating interfacial properties, and scalability. [ABSTRACT FROM AUTHOR]

Nanograined BaTiO3 ceramics prepared from 40-nm-size BaTiO3 nanopowders exhibited the cubic as well as the tetragonal phase, while nanograined BaTiO3 ceramics prepared from BaTiO3 nanopowders coated with Mn had only the tetragonal phase. The dielectric constant of the latter was 10 times larger than that of the former; the latter exhibited PTCR behavior with a resistivity jump ratio of about 5.0 × 104. These physical properties of the BaTiO3 ceramics appeared to be significantly affected by the strain near grain boundaries; such strain resulted in a phase transition from the cubic to the tetragonal phase in the nanograined BaTiO5 ceramics, even though the grain size was about 40 nm. [ABSTRACT FROM AUTHOR]

Various environmental concerns motivate scientists and researchers to look out for unique new materials in science and technology. In order to address the demand for polymeric materials with partial biodegradability, the usage of lignocellulosic fibre in the polymer matrix has risen. Lignocellulosic fibres are a cheap, easily renewable resource that is readily available in all regions. Cellulosic plant fibres also have a plethora of possibilities for use in polymer reinforcement because of their properties. Many researchers put their effort into developing a natural polymer with better mechanical properties and thermal stability using nanotechnology and the use of natural polymers to make its composites with lignocellulosic fibres. This study provides a review of the biodegradable composite market, processing methods, matrix-reinforcement phases, morphology, and characteristic improvements. In addition, it provides a concise summary of the findings of significant research on natural fibre polymer composites (NFRCs) that have been published. Indeed, a noticeably brief discussion is provided on the significant issues faced during composite extraction as well as the challenges encountered during the machining. Recent developments in the study of lignocellulosic fibre composites or NFRCs have demonstrated their enormous potential as structural elements in vehicles, aerospace structures, buildings, ballistics, soundproofing, and other structures. [ABSTRACT FROM AUTHOR]

Biological aspects of polymer nanocomposites (PNCs) depend on various factors like low toxicity, stimuli-responsive behavior, high compatibility, and large aspect ratio along with size-dependent properties of fillers. A range of parameters influencing the biological activities of PNCs is established in the present review. Biomedical applications of PNCs like drugs delivery, gene therapy, tissue engineering, cancer treatment, wound healing, dental curing, biosensing, and bioimaging are contained including antibacterial behaviors. Physical and biological characteristics are explained to enable the PNCs for various biomedical uses. For a better understanding of the subject, several schemes and comparative tables are established in different sections of the review. [ABSTRACT FROM AUTHOR]

Xia et al. [[15]] simulated the behavior of xenon (Xe) bubbles in uranium dioxide (UO SB 2 sb ) grain boundaries by using the molecular dynamics method. Xe atoms were more regular in the bulk, whereas multiple Xe atoms formed a planar structure at the GBs. The activation energy of interstitial Xe/Kr atoms and clusters in UO SB 2 sb is ~2 eV, indicating that the diffusion of the interstitial atoms is very difficult. Zeng et al. [[10]] simulated the adsorption and diffusion behaviors of a Na atom on a Mo (110) surface with the presence of Re and O atoms by the first-principles approach. [Extracted from the article]

Unlike malleable polymers or metals, ceramics and many other inorganic materials are harder to process, because of their brittle nature and high melting points. If these refractory materials can be liquefied at lower temperatures, their fusion, molding, casting, mixing, deformation, segmentation, carving, and polishing will be greatly facilitated. Herein, a stress‐induced liquefaction mechanism that transforms "ice‐like" (shrinking upon melting) materials into supercooled liquids at room temperature, opening a route for processing refractory substances, is reported. Furthermore, this discovery sheds light on key puzzles in materials science, particularly how life fuses and modifies bioceramics in water under ambient conditions. [ABSTRACT FROM AUTHOR]

Graphene has excellent electromagnetic, mechanical, thermal, and optical properties and has been widely applied in materials science, biomedicine, physics, energy storage, chemistry, and textile fields all over the world. In this paper, graphene conductive fabrics were prepared by the impregnation method, and ascorbic acid was used as a reducing agent. Ammonia-cotton blended fabric was used as the base material. Results indicated that graphene had been successfully covered on fabrics according to XRD and SEM analysis. The optimum technological parameters for preparing graphene conductive fabrics were: impregnation five times, reduction temperature at 95 °C, the ascorbic acid concentration of 0.06 mol/L, and the reduction time was 40 min. A corrosion study indicated that rGO fabrics could be partly corroded in 3 wt.% NaCl solution, leading to a decrease in resistivity. However, the conductive ability of rGO fabric changed little with time due to the good stability of rGO. [ABSTRACT FROM AUTHOR]

Micro-nano particle manipulation methods in liquid environments have been widely used in the fields such as medicine, biology and material science. Nevertheless, the methods usually rely on pre-prepared physical microfluidic channels. In this work, virtual electrodes based on the optically induced dielectrophoresis (ODEP) method were used as virtual microchannels instead of traditional physical microfluidic channels. Virtual microchannels with different shapes were implemented by the designs of projected light patterns, which made the virtual microchannels have great flexibility and controllability. The theory of ODEP was verified by simulation and analysis of electric field distributions. The relationship between the manipulation force and the alternating current (AC) voltage or the AC frequency exerted on the cells was assessed. The experimental results indicated that the manipulation force was increased with the increase of the AC voltage, and it was reduced with the increase of the AC frequency. Moreover, different virtual microchannels were designed to carry out the transportation, aggregation and sorting of yeast cells and rat basophilic leukemia cells (RBL-2H3 cells) and the survival rate of the cells was evaluated. This work shows that the virtual microchannels can be flexibly realized by ODEP in liquid environments. [ABSTRACT FROM AUTHOR]

Abstract: ZrO2 porous nanosolid has been successfully prepared by a novel hydrothermal hot-press (HHP) method, using ZrO2 nanoparticles and deionized water as the starting materials. Furthermore, an organic dye, rhodamine B (RhB) was assembled into the pores of ZrO2 porous nanosolids, and RhB/ZrO2 porous nanocomposite was obtained. Because of the interaction between RhB molecules and the surface atoms of ZrO2 porous nanosolid, a photoluminescence (PL) enhancement and a blue-shift of the PL peak were observed in ZrO2/RhB composites compared with that of RhB. [Copyright &y& Elsevier]

Due to their attractive strength-to-weight ratios, stiffness-to-weight ratios, thermal expansion, corrosion resistance, and vibration resistance properties, carbon fiber reinforced plastic (CFRP) composites have been widely used in applications ranging from aerospace to sporting goods. Considering some of the advantages of additive manufacturing (AM) over traditional subtractive methods, AM is being used to fabricate CFRP composites. For the fabrication method, several investigations have been conducted on materials and processing effects on the mechanical performance of the composites. However, no studies have investigated the effects of environmental conditions on mechanical performance. This study reports the environmental (temperature and relative humidity) affected mechanical performance of AM fabricated CFRP composites exposed to three different environmental conditions: warm–wet, warm–dry, and cold–dry, compared to samples tested immediately after fabrication under normal ambient conditions. The result was that the warm temperatures have insignificant effects on the mechanical performance of the composites, while near-zero degree cold temperatures have significant effects after the 96 h and 250 h short-term exposure periods. The result also showed the temperature to have more significant effects on mechanical properties than relative humidity. Under the warm conditions, the dry humidity resulted in a slight increase in material mechanical properties over the nominal ambient condition, while the wet humidity showed an insignificant reduction in material mechanical properties. [ABSTRACT FROM AUTHOR]

Metal-bond diamond tools find extensive use in the grinding of hard and brittle materials. The mechanical properties and wear resistance of the metal bond are crucial for the grinding performance and life of diamond tools. However, Fe bonds exhibit insufficient hardness, strength, and wear resistance, and existing reinforcement methods are difficult to simultaneously improve the self-sharpness and wear resistance of diamond tools, leading to a trade-off between grinding performance and life. In this paper, a novel AlCoCrFeNi HEA particles reinforced Fe (HEA/Fe) alloy was proposed as the bond for diamond tool to address the aforementioned issue. The work considers materials science fundamentals related to the element diffusion mechanism and particle reinforcement mechanism in the design of the HEA/Fe bond. Through the mutual element diffusion between the HEA and Fe matrix, expanded HEA regions are formed, which not only enhance the strength and overall wear resistance of the HEA/Fe bond but also generate a composite structure with varying hardness. The distinct mechanical properties of composite structure form wear-resistant and non-wear-resistant areas within the diamond tool, effectively balancing the challenging trade-off between wear resistance and self-sharpness. This allows HEA/Fe bond diamond tools to achieve both prolonged service life and high grinding performance. The results reveal that the HEA/Fe bond diamond tool exhibits a lower grinding force, a superior surface finish, and a nearly equivalent grinding ratio compared to the commercial Fe-based alloy bond diamond tool in grinding of sapphire. [Display omitted] • The element diffusion and phase formation mechanisms of HEA/Fe alloys were investigated. • The influence of HEA content on the mechanical property of HEA/Fe alloys was investigated. • The HEA/Fe bond diamond tool exhibited a lower grinding force, a superior surface finish, and a nearly equivalent grinding ratio compared to the commercial Fe-based alloy bond diamond tool in grinding of sapphire. [ABSTRACT FROM AUTHOR]

The review summaries our achievements in biomineralization. A new understanding of non‐classical nucleation is introduced, which highlights the formation of ionic clusters during the early mineral formation. This discovery directs to a new chemical concept of inorganic ionic oligomers and their crosslinking. Different from the conventional syntheses of inorganic materials, the inorganic ionic oligomers can be used as the conformable precursors to achieve moldable constructions, which arises from a fusion of classic inorganic and polymer chemistry by sharing the same process for the manufacture of materials. By using the inorganic oligomers, the biomimetic regenerations/ repairs of hard tissues such as tooth enamel and bone can be realized. And the advanced artificial materials superior over biological ones can be developed by inorganic‐organic co‐polymerization. Moreover, biomineralization is a tool for the integration of materials and biological organism. Our attempts demonstrate that the rationally designed materials‐biologicals can contribute to vaccine improvement, universal blood transfusion, and cancer treatment, etc. They follow a transformation of biomineralization study from biomimetic synthesis of materials to biomimetic modification of organisms and furthermore, start an understanding of chemical biological regulation by materials. What is the most favorite and original chemistry developed in your research group? The discovery of ionic oligomers and their crosslinking following a new concept of inorganic ionic polymerization. How do you get into this specific field? Could you please share some experiences with our readers? I got into the field of biomineralization when I was a graduate student. A challenge in biomineralization community is how we can achieve a moldable construction of inorganic materials (biominerals). Fortunately, we observed the formation of ultrasmall ion aggregates at the early nucleation strategy. This finding subsequently directed to our exploration of ionic oligomers and the most important key was a new start of this inorganic study upon a view of polymer chemistry. How do you supervise your students? I keep on asking my students two questions: 1) What unsolvable problem can you solve for our society by your study? 2) What new understanding can you contribute to our scientific community by your study? What is the most important personality for scientific research? Ready to accept challenge, persist and never give up. What are your hobbies? What's your favorite book(s)? I like travel since I can feel different culture and learn many different ideas in the travelling. I prefer history books since I can "earn" much valuable experience in the reading. How do you keep balance between research and family? Working effectively in weekday and relaxing completely in weekend. Who influences you mostly in your life? The group of my friends and colleagues. I learn lots to improve myself under their help and criticisms. Could you please give us some advices on improving Chinese Journal of Chemistry? To induce the best chemical research in China, beginning from review papers but finally moving to the top research papers. [ABSTRACT FROM AUTHOR]

Dielectric materials with high thermal conductivity (TC) can enable disruptive performance enhancement in the areas of electronics packaging, thermal management, energy storage, cabling, and heat sinks. There have been widespread global efforts over the past decade on developing novel nanocomposite dielectric materials. As a baseline, legacy polymers and epoxies used in the abovementioned applications have very low thermal conductivities ranging from 0.1–0.5 W ⋅ m−1 ⋅ K−1. Recent advances have led to the commercial availability of polymeric materials with thermal conductivities approaching 10 W ⋅ m−1 ⋅ K−1. Importantly, several fundamental studies report novel nanocomposites with thermal conductivities > 50 W ⋅ m−1 ⋅ K−1. This article summarizes progress in the development of such materials with a focus on developments that show promise for improved practical dielectrics. This review highlights that high TC alone is inadequate to characterize the suitability of any material for the above applications. Other thermal properties, such as thermal diffusivity, glass transition temperature, and the ratio of the in-plane to out-of-plane TC, are important to quantify the thermal performance of novel nanocomposites. In addition, characterization and understanding of mechanical properties (coefficient of thermal expansion (CTE), tensile strength and elastic modulus) and electrical properties (dielectric strength and dielectric permittivity) are critical for holistic multifunctional assessments of these materials. There are other parameters and properties that influence performance, life, and manufacturability, such as viscosity and moisture absorption. This study reviews all the above aspects of nanocomposite dielectric materials reported in the literature. More specifically, we analyze various filler-polymer combinations, and the influence of approaches to incorporate fillers in the polymer on the thermal, mechanical, and electrical properties. While the addition of fillers leads to huge enhancements in TC, the TC is highly anisotropic, with out-of-plane TC lower than in-plane TC by an order of magnitude. It is seen that most present-day materials are still inadequate for future applications due to their low glass transition temperatures; specific promising materials are highlighted. While the addition of fillers reduces the CTE, further reduction is needed to favorably improve the mechanical performance of these materials. While the electrical insulating properties of these composite materials are adequate, there is very little data reported on other electrical properties. In summary, while there is an understandable focus on enhancing the TC, other properties are underreported, and there is insufficient information to support the assessment of most novel materials for practical applications. Overall, this study summarizes the state-of-the-art dielectric nanocomposites and outlines directions for future research to bridge the gap between basic materials science and applications. [ABSTRACT FROM AUTHOR]

As we live in a time of heightening environmental issues, materials science is required to prepare sustainable polymers through green chemistry ideals. Vegetable oils and their fatty acid derivatives are well regarded for their use in polymer chemistry. Click chemistry has drastically affected the synthesis of vegetable oil-derived polymers over the last twenty years. This review covers the most recent and relevant developments in click chemistry as a functionalization and polymerization method of vegetable oils and their derivatives. First, a quick overview is provided of the main macromolecular architectures and properties of the most commonly accessible vegetable oils, their most prevalent chemical modifications, and their prevalence in polymer families. It is followed by an introduction of the click chemistry reactions frequently developed on vegetable oils. The focus of the manuscript is the development of this efficient chemistry for the synthesis of polymer materials derived from vegetable oils. [ABSTRACT FROM AUTHOR]

Here, we show the successful implementation of advanced sequential logic in droplet microfluidics, whose principles rely on capillary wells establishing stationary states, where droplets can communicate remotely via pressure impulses, influencing each other and switching the device states. All logic operations perform spontaneously due to the utilization of nothing more than capillary–hydrodynamic interactions, inherent for the confined biphasic flow. Our approach offers integration feasibility allowing to encode unprecedentedly long algorithms, e.g., 1000-droplet counting. This work has the potential for the advancement of liquid computers and thereby could participate in the development of the next generation of portable microfluidic systems with embedded control, enabling applications from single-cell analysis and biochemical assays to materials science. [ABSTRACT FROM AUTHOR]

Carrier mobility (weighted mobility more specifically) of thermoelectrics fundamentally determines its power factor, representing a new cut‐in point to optimize the thermoelectric performance. However, researches on enhancing the carrier mobility to improve power factor has been overlooked. In present work, we highlight a significant mobility enhancement in BiTeI by introducing I deficiency, which improves the power factor and final ZT value. A defect compensation weakening mechanism is adopted that the induced I vacancies reduce the concentration of intrinsic ITe• and TeI' antisite defects, which weakens the donor‐acceptor defect compensation and suppresses the defects‐induced carrier scattering. As a result, the carrier mobility is obviously enhanced in I‐deficient samples, which ensures an effectively improved power factor and final ZT. A maximum ZT of 0.57 is achieved at 570 K perpendicular to the pressing direction, which is superior to pristine BiTeI and among the highest values reported for bulk BiTeI‐based thermoelectric materials. Present work opens up a new avenue for thermoelectric optimization mainly by mobility enhancement. [ABSTRACT FROM AUTHOR]

Natural fibre-reinforced polymer composites are increasingly replacing commercial composite materials. The limitations of conventional composites materials are overcome by green composites, which are easily available, more eco-friendly and less toxic. In the current scenario, green composites are emerging in the field of material science that involves improving their physical, mechanical and thermal properties. The poor interfacial adhesion and surface incompatibility between natural fibre and biodegradable polymers lead to reduced physico-mechanical properties. In order to overcome this issue, physical and chemical modification methodologies of the natural fibre and polymer matrix are employed, among which the addition of coupling agents has a critical contribution. This paper compiles several recent research works in the utilization of coupling agents such as silane, maleic anhydride, isocyanate, triazine, etc., with the various combinations of natural fibres and polymers. In addition to this, the extents of influence of coupling agents on the characteristics of the natural fibre reinforced composite materials are also reported. This gives an overview for the future researchers to identify the gap in the field of green composite materials and novel coupling agents for different natural fibre/polymer matrix combination. [ABSTRACT FROM AUTHOR]

Light transmitting and electromagnetic wave shielding material using a cross-polarizing effect of unidirectionally aligned electrically conductive fiber-dielectric composite has been developed. Two-electrically isolated unidirectionally aligned continuous electrically conductive fiber layers were incorporated into an optically transparent polymethylmethacrylate (PMMA) matrix. Electromagnetic wave shielding by the polarizing effect of the composite was examined by the free-space method in a frequency range from 18 to 24 GHz. The composite shields electromagnetic wave with a small expense of light transmittance of the PMMA matrix. Effect of fiber spacing, angle of fiber axis direction, and polarizing mode of incident electromagnetic wave are discussed based on experimental results. It is concluded that the use of the polarizing effect is an effective way to obtain an optically transparent electromagnetic shielding material. [ABSTRACT FROM AUTHOR]

We have investigated the thermal and electrical properties of filled skutterudites belonging to the series Ce1-zYbzFe4Sb12 and Cey/2Yby/2Fe4-x(Co/Ni)xSb12, as well as their potential for thermoelectric power generation. In the first series, increasing the Yb fraction decreases the resistivity and thermopower. These effects are related to the variations of valence of Yb with the Yb fraction (from 2.2 in Yb0.92Fe4Sb12 to 2.7 in Ce0.85Yb0.05Fe4Sb12). The power factor is increased in Ce0.40Yb0.53Fe4Sb12 while the thermal conductivity is reduced and this leads to an improved figure of merit in this compound when compared to Ce0.85Fe4Sb12. Co or Ni substitution was used to tune the carrier concentration and improve the power factor: we measure a ZT=0.5 at 500 K in Ce0.44Yb0.32Fe3.02Co0.98Sb12 and an extrapolation leads to ZT=0.95 at 800 K, which is close to state-of-the-art Ce0.28Fe1.52Co2.48Sb12 although the composition is far from being optimized. Double filling happens to be a promising path to provide good thermoelectric performances. [ABSTRACT FROM AUTHOR]

The Special Issue on "Metallurgical Slag" is a collection of 23 original articles dedicated to theoretical and experimental research works providing new insights and practical findings in the field of metallurgical slag-related topics. 10.3390/cryst10110971 6 Shi G.Y., Zhang T.A., Dou Z.H., Niu L.P. Dissolution Behavior of Al2O3 Inclusions in CaO-Al2O3 Based Slag Representing Aluminothermic Reduction Slag. 10.3390/cryst11060583 3 Xu Y., Song P., Cao W., Li H., Liang J. Effect of Al2O3-SiO2 Addition on Gehlenite Growth and the Mechanical Performance of Steel Slag. Further examples of hydrometallurgy are given by Li et al. [[15]] who designed an electrochemical method that could be used to remove impurities in zinc leaching night and enrich zinc ferrite in the ammonia leaching residue of the solution, and that of ammonia leaching slag after ammonia leaching of zinc hypoxide. [Extracted from the article]

A unique approach to crack-free joining of heterogeneous ceramics is demonstrated by the use of sialon polytypoids as Functionally Graded Materials (FGM) as defined by the phase diagram in the system, Si3N4-Al2O3. Polytypoids in the Al2O3-Si3N4 system offer a path to compatibility for such heterogeneous ceramics. The first part of the dissertation describes successful hot press sintering of multilayered FGM's with 20 layers of thickness 500 mm each. Transmission Electron Microscopy was used to identify the polytypoids at the interfaces of different areas of the joint. It has been found that the 15R polytypoid was formed in the Al2O3-contained layers and the 12H polytypoid was formed in the Si3N4-contained layers. The second part of the dissertation discusses the mechanical properties of these polytypoidally joined Si3N4-Al2O3. The thermal stresses of this FGM junction were analyzed using a finite element analysis program (FEAP) taking into account both coefficient of thermal expansion (CTE) and modulus variations. From this analysis, the result showed a dramatic decrease in radial, axial and hoop stresses as the FGM changes from three layers to 20 graded layers. Scaling was considered, showing that the graded transition layer should constitute about 75 percent or more of the total sample thickness to reach a minimal residual stress. Oriented Vickers indentation testing was used to qualitatively characterize the strengths of the joint and the various interfaces. The indentation cracks were minimally or not deflected at the sialon layers, implying strong interfaces. Finally, flexural testing was conducted at room temperature and at high temperature. The average strength at room temperature was found to be 581 MPa and the average strength at high temperature (1200 degrees C) was found to be 262 MPa. Scanning electron microscope observation of fracture surfaces at a different loading rates indicated that the strength loss at higher temperatures was consistent with a softening of glassy materials present at grain junctions.

This review article deals with orientation controlled growth of Carbon Nanotubes (CNTs). Vertically aligned CNTs (VACNTs) are considered as the best type of CNTs among all known forms. The present article covered various aspects required for the successful growth of orientation controlled CNTs especially vertically aligned form. We discussed in details about the important properties of VACNTs and the importance of VACNTs in materials science with relative applications. It included different types of CVD techniques which support the vertically aligned CNTs growth on the substrate and also supports its mass production with proper growth mechanism. We made a detailed discussion about catalyst engineering and different type of carbon sources. The catalyst lifetime is a key factor for growing long CNTs, so, the reason of catalyst poisoning and the protection of catalyst from poisoning is also a part of our article. We also explained in detail about the types of catalyst protector elements with their suitability on different temperature as well for different gases used for continuous growth of VACNTs, yarns of CNTs as well as bulk production of CNTs. We covered a broad study about the various catalysts, catalyst thickness and catalyst deposition techniques. The suitable supporting layers for different catalysts with their impacts on morphology as well as on the structure of as grown CNTs are also discussed. For reducing cost of VACNTs production, we included eco-friendly natural wastage materials for catalysts and as carbon precursor. It also included the process by which different designs and structures of VACNTs can be made specifically by bending of VACNTs during growth running time through the utilization of different catalyst reservoirs. The discussion made in present article on the growth of oriented CNTs will help to grow selective vertically aligned CNTs in the convenient way with economical rate and thereby helps in the mass production of CNTs. [ABSTRACT FROM AUTHOR]

Bamboo can be processed into engineering materials with excellent properties by reasonable processing methods. In this study, the performance of mould-pressed bamboo (MBP) veneer products was examined. The physical mechanical properties and connection properties of MPB were tested, and the application performance of the MPB was analyzed. The results show that MPB has a comprehensive property of high internal bonding and good dimensional stability, and its density and mechanical properties are similar to those of wood dimensional stock. The overall bending strength, bending modulus, and compression strength of MPB were 29.0 MPa, 6.83 GPa, and 15.6 MPa, respectively. While the overall carrying capacity was relatively low, the connection performance of BPM was good. Thus, it can be used as a connector or substructure. [ABSTRACT FROM AUTHOR]

This review presents a general survey on synthesis and processing techniques of tungsten copper (W-Cu) composite powders for achieving electrical contact materials for power engineering applications. Several chemical and mechano-chemical synthesis methods for obtaining W-Cu composite powders in nano or micro scales from various W and Cu metal salt precursors combined with hydrogen reduction or nitridation-denitridation processes are reported along with powder metallurgy (PM) techniques employed in manufacturing W-Cu electrical contact materials. The main advantages and disadvantages of synthesis and processing techniques are summarized, too. The interdepencies among the properties of starting materials and final products in relation with synthesis and processing parameters are highlighted. The review reveals that the development of W-Cu advanced materials with improved properties and scale-up potential is of a great interest in practical applications related to materials science and engineering field. [ABSTRACT FROM AUTHOR]

The design and production of anisotropic composites and nanocomposites has become increasingly relevant in materials science and engineering because they provide an opportunity of enhancing and adapting the properties of a material for specialized applications. This article reviews the strategies that have been developed to achieve anisotropy based on the position and orientation of the dispersed phase in polymer composites including polymer nanocomposites. Flow and electric field-driven alignment methodologies are briefly described, which is followed by a focus on magnetically oriented composites. The use of magnetic fields for this purpose has been of particular interest in recent years due to its ease of use and the variety of materials on which this method can be applied. Strong magnetic fields are required to align diamagnetic fillers. However, the modification of particles with low magnetic susceptibilities with magnetic nanoparticles (i.e. iron oxide nanoparticles) has been proven to be a successful approach to broaden the capabilities of magnetic alignment in polymer composites. The development of filler manipulation techniques opens the possibility to mimic complex biological structures that promise to improve the mechanical properties of bioinspired composites and even achieve advanced functionalities in self-shaping materials for example. [ABSTRACT FROM AUTHOR]

The study of thermoelectric materials spans condensed matter physics, materials science and engineering, and solid-state chemistry. The diversity of the participants and the inherent complexity of the topic mean that it is difficult, if not impossible, for a researcher to be fluent in all aspects of the field. This review, which grew out of a one-week summer school for graduate students, aims to provide an introduction and practical guidance for selected conceptual, synthetic, and characterization approaches and to craft a common umbrella of language, theory, and experimental practice for those engaged in the field of thermoelectric materials. This review does not attempt to cover all major aspects of thermoelectric materials research or review state-of-the-art thermoelectric materials. Rather, the topics discussed herein reflect the expertise and experience of the authors. We begin by discussing a universal approach to modeling electronic transport using Landauer theory. The core sections of the review are focused on bulk inorganic materials and include a discussion of effective strategies for powder and single crystal synthesis, the use of national synchrotron sources to characterize crystalline materials, error analysis, and modeling of transport data using an effective mass model, and characterization of phonon behavior using inelastic neutron scattering and ultrasonic speed of sound measurements. The final core section discusses the challenges faced when synthesizing carbon-based samples and the measuring or interpretation of their transport properties. We conclude this review with a brief discussion of some of the grand challenges and opportunities that remain to be addressed in the study of thermoelectrics. [ABSTRACT FROM AUTHOR]

The use of rice husks (RH) to reinforce polymers in biocomposites are increasing tremendously. However, the incompatibility between the hydrophilic RH fibers and the hydrophobic thermoplastic matrices leads to unsatisfactory biocomposites. Surface modification of the fiber surface was carried out to improve the adhesion between fiber and matrix. In this study, the effect of surface modification of RH via alkali, acid and ultraviolet-ozonolysis (UV/O3) treatments on the properties of composites recycled high density polyethylene (rHDPE) composites was investigated. The untreated and treated RH were characterized by Fourier Transform Infrared (FTIR) and Scanning Electron Microscope (SEM). The composites containing 30 wt% of RH (treated and untreated) were then prepared via extrusion and followed by compression molding. As compared to untreated RH, all surface treated RH exhibited rougher surface and showed improved adhesion with rHDPE matrix. Tensile strength of UV/O3-treated RH composites showed an optimum result at 18.37 MPa which improved about 5% in comparison to the composites filled with untreated RH. UV/O3 treatment promotes shorter processing time and lesser raw material waste during treatment process where this is beneficial for commercialization in the future developments of wood plastic composites (WPCs). Therefore, UV/O3 treatment can be served as an alternative new method to modify RH surface in order to improve the adhesion between hydrophilic RH fibre and hydrophobic rHDPE polymer matrix. [ABSTRACT FROM AUTHOR]

ABSTRACT: As self‐lubricating bearing liner materials, tribological properties of milled pitch‐based carbon fibers (CFs) modified polytetrafluoroethylene (PTFE)/Kevlar fabric composites were investigated, and the microscopic morphology of worn surface was studied. The results show that the appropriate incorporation of CFs can obviously reduce the wear rate of the fabric composite with almost unchanging friction coefficient. The wear rates of 5 wt % CF‐filled PTFE/Kevlar fabric composites are decreased by 30% and 48% for two kinds of composites made with fibers from different producers compared with unfilled fabric composites. Scanning electron microscopy observations show that the appropriate incorporation of CFs obviously improves the interfacial bonding and reduces pull‐out and fracture of Kevlar fiber. Meanwhile, the introduction of CFs at proper fraction is helpful to form smooth and continuous transfer film on the surface of metal counterpart. The improving mechanism of the CF is attributed to increasing mechanical strength, thermal conductivity and self‐lubricating effects. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46269. [ABSTRACT FROM AUTHOR]

The curing process is critical in the production of composite materials. In this paper, a heat transfer and curing kinetics of the two-way coupling model reflecting the resin-based composite curing process was built. The degree of curing and temperature fields simulation programme using the finite difference method independently was also developed. With this programme, a numerical simulation for a flat plate was conducted. The distributions of temperature and degree of curing fields were obtained. The simulation results indicated that temperature distribution plays an important role in the resin curing process. The internal temperature of autoclave is inhomogeneous. The temperature of the composite has a non-linear relationship with the gradient temperature distribution in the autoclave. Moreover, the existence of temperature difference inside the autoclave can have a more significant influence at a low temperature than that of a high one. This research provides a certain basis for optimising the moulding process parameters, mould design and product quality control. [ABSTRACT FROM AUTHOR]

Even though self-nucleation is considered to be the ideal case for polymer nucleation, it has rarely been used to enhance polymer crystallization in practical processing techniques. Inspired by self-nucleation theory and by utilizing the large difference in melting points of various poly(l-lactide) (PLLA) resins, we introduced high-melting-point PLLA (hPLLA) crystallites into a low-melting-point PLLA (lPLLA) matrix via melt blending at a processing temperature between the two melting points of the selected PLLA resins. The hPLLA crystallites turn out to be efficient nucleating agents (NAs) for lPLLA and high crystallinity (＞40%) PLLA samples with a greatly accelerated crystallization rate can be easily obtained. The results of non-isothermal crystallization show that the crystallization process is remarkably accelerated with a small amount (0.1 wt%) of hPLLA. With a further increase of hPLLA content, the crystallization temperature of the blends continues to shift to higher temperature. This crystallization promoting effect results from the excellent nucleation ability of the hPLLA crystallites, as revealed by in situ optical microscopy observation. Furthermore, an incredibly high nucleation efficiency of 103.0% (exceeding 100%) was obtained for the PLLA sample with 5.0 wt% hPLLA. The nucleation mechanism for hPLLA was studied systematically. It was found that the lPLLA matrix and hPLLA crystallites possess an absolutely identical crystal structure of α-form crystals and an excellent interfacial interaction between the nucleating agent, i.e., hPLLA crystallite, and the lPLLA matrix is achieved, resulting in the reduction of the energy barrier for heterogeneous nucleation and acceleration of crystallization kinetics. Therefore, by using high-melting-point polymer crystals as NAs, the crystallization rate of their low-melting-point polymer matrix can be improved largely, thus providing a simple way to obtain high crystallinity products for semicrystalline polymers with very low crystallization rates. [ABSTRACT FROM AUTHOR]

Surface densification of solid wood increases the density on the surface, when compressed by single side heated press. A recent experimental study has pointed out the influence of the process parameters on the development of the density profiles in the modified samples. Numerical modelling can help to optimize the experimental work which is often time consuming and laborious due to the large amount of experiments required to check the influence of the pressing parameters. In the present work, a FEM simulation of the hygro-thermal behaviour of wood under surface densification is proposed by using a three-dimensional hygro-thermal model based on earlier literature approaches. The model is implemented in a user subroutine of the FEM code Abaqus starting from the definition of a weak form of the governing hygro-thermal equations of the problem. The numerical profiles of moisture content and temperature during the wood densification process are simulated for some wood specimens tested in a previous study. Conclusions are given on the relationship between these profiles and the experimental density profiles due to different process parameters. [ABSTRACT FROM AUTHOR]

The article describes the development of a numerical material model of ceramic matrix composite (CMC) reinforced by bundles of thousands of short carbon fibres and produced by means of a liquid silicon infiltration process. The objective of the article is the development of a numerical mesoscale model that considers the material as a simple bi-phasic composite constituted by an isotropic matrix with differently sized inclusions. The distinctive material microstructure that complicates the development of such a model is presented and the issues represented by the generation of the finite element models and by the identification of the effective properties of the constituent phases are discussed. In the presented approach, models are generated by numerically simulating the packing of bundles and phases are identified by means of tests and numerical analyses, which are performed on long fibre-reinforced specimens and on specimens subjected to a thermal process for the elimination of carbon reinforcement. The approach is applied to find out the parameters of a homogenized orthotropic model for CMC plates. The obtained results show that the numerical packing simulations can generate models with a realistic distribution of size, shape and orientation of the bundles. The mesoscale model and the phase properties identified by the proposed numerical and experimental procedure are validated by considering the stiffness of standard CMC specimens obtained in three-point bending tests. According to the results, the developed methodologies can be considered as a promising approach for a reliable prediction of short fibre-reinforced CMC elastic properties. [ABSTRACT FROM AUTHOR]

The harnessing of heat emanating from powder-based exothermic reactions to produce advanced materials has been around for many decades, and is manifested in the process of combustion synthesis (CS). A plethora of work has been published on the topic covering fundamental aspects of the process for a large number of material systems. Over time, CS has been combined with other processes and effects to potentially improve on conventionally produced CS products and alleviate some of the inherent disadvantages of CS. This article discusses processing aspects of CS, and provides a review of CS-related hybrid processes with the intent to exemplify the diversity of CS processing. Approaches such as reactant microstructural design, reactive bulk deformation/compaction processes, reactive casting, laser-assisted CS, activation techniques (field/current, mechanical, microwave), and unconventional heat treatments are discussed together with other methods. [ABSTRACT FROM AUTHOR]

A modified softwood product would enable the utilization of softwood in new areas. Densification is an old modification method to improve wood properties such as hardness and resistance to abrasion. A major problem with densified wood is, however, its ability to retain its original dimensions under the influence of moisture. Therefore, this study investigated the influence of surface to bottom layer thickness ratio on the shape stability of a modified and three-layered cross-laminated engineering wood product (EWP) subjected to moisture variations. The study describes a simple solid wood densification technique based on compressing a clear solid piece of softwood with vertical annual rings in the radial direction by restraining the tangential expansion. Three-layered cross-laminated EWP was manufactured with the densified wood as a surface layer. The recovery of the densified wood in the surface layer was then reduced to movements in the same level as the other two layers of unmodified wood. The EWP was subjected to climatic variations in order to investigate its shape stability. The results disclosed that an appreciable degree of shape stability was obtained by an increase in the surface to bottom layer thickness ratio of the EWP. [ABSTRACT FROM AUTHOR]

Two kinds of environmental friendly composites were prepared based on sustainable matrices, respectively, defatted cross-linked soy flour and thermoplastic polyhydroxybutyrate cohydroxyvalerate, reinforced by natural fibers from Caroà and Kenaf plants. The obtained composites were compared in terms of moisture tolerance, thermal and mechanical properties, and thermoregulation ability. It was found that this ecofriendly systems have suitable properties for indoor applications in housing and transportation. [ABSTRACT FROM AUTHOR]