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Alumina-based multilayer laminates with layers of varied porosities and ceramic fiber reinforcements, which can be achieved by including paper-derived ceramic layers, are interesting candidates for chemically stable and thermal shock resistant materials. In order to investigate the complex sintering behavior of these laminates, the sintering of each alumina layer contained within a laminate, each one with its individual sintering anisotropy and sintering shrinkage, has to be considered separately. For this purpose, sintering curves are determined by dilatometry measurements, serving a consecutive examination by an analytical model. Modeling parameters specific to each layer, are applied in finite-element-type sintering simulations for symmetrical multilayer laminates. Differences in the sintering shrinkages may cause internal stresses at layer interfaces and, in turn, may influence the thermal and mechanical properties of multilayer laminates after sintering. Accordingly, the prediction of developing internal stresses within alumina-based multilayer laminates by the presented sintering simulations is a key aspect of this study. [Display omitted] • Individual laminates sintering dilatometry. • Anisotropic sintering assessment by analytic modeling. • Finite element simulation of multilayer laminates sintering. [ABSTRACT FROM AUTHOR]

This paper describes the fabrication and characterization of porous SiC ceramics derived from highly-filled preceramic papers. The SiC ceramics were obtained by spark plasma sintering of stacked preceramic papers at temperatures of 2100 and 2200 °C under pressures of 5–60 MPa for 10 min. The microstructure and phase composition were analyzed by scanning electron microscopy and X-ray diffraction, respectively. Gas permeation tests were performed using hydrogen permeation cell at room temperature. It is revealed that the porosity of sintered SiC can be varied from 9 to 45 % depending on the sintering parameters. The shrinkage of the materials during spark plasma sintering occurs in four stages. The linear shrinkage value of the material increases from 7 to 47 % at 2100 °C and from 20 to 50 % for the samples sintered at 2100 and 2200 °C, respectively. Correlation dependencies between porosity and mechanical properties of the fabricated SiC were established. The obtained porous SiC ceramics exhibit high bending strength of 165 MPa and gas permeation flux of 78 molH 2 /m2/s at the porosity of 36 % that make it suitable for ceramic-based membranes. [ABSTRACT FROM AUTHOR]

Through the pyrolysis of cellulose-based paper templates infiltrated with a suitable polymer precursor, ceramic composites exhibiting a paper-like structure can be conveniently prepared. Such polymer-derived ceramic papers (PDCPs) unite the unique morphology of regular cellulose papers with the properties of the ceramic system utilized. Here, two paper templates, made from eucalyptus and cotton, respectively, were infiltrated with two polysilazane-based polymer precursors modified with either Fe, Ni, or Pd and converted into multi-phasic ceramic papers. In addition to the type of paper template, precursor composition, and transition metal used, the present study aims to rationalize the influence of pyrolysis temperature and atmosphere on the morphology, microstructure, and phase composition of the ceramic papers generated. For this purpose, scanning electron microscopy, SEM, and (scanning) transmission electron microscopy, (S)TEM, in conjunction with EDS analyses were used to elucidate the microstructural features of the ceramic composites in great detail. It is shown that the transition metals precipitate as nanosized metallic particles and silicides in the case of Pd and Ni, while the introduction of Fe features oxide and carbide phases in addition to that. Moreover, the metals catalyze both the graphitization of the cellulose fibers and, at higher temperatures, the generation of whisker-like Si-based nanostructures composed of either SiC or Si 3 N 4 , depending on the processing atmosphere used. [ABSTRACT FROM AUTHOR]

Accelerated thermal aging was conducted on Kraft papers impregnated with mineral insulating oil (MO) and palm insulating oil (PO), and the effect of aging time on the oils and Kraft papers was observed. Each sample consisted of insulating oil, dried Kraft paper, and weighed metal catalysts (copper, iron, zinc, and aluminum) in a bottle. Prior to aging, the bottles were left for 24 h at room temperature for impregnation to take place. The thermal aging experiments were carried out at 130 °C for 250, 500, and 750 h. The properties of the MO and PO (moisture content, acidity, and ultraviolet-visible absorption spectra) and the properties of the Kraft papers (tensile strength and colour) were determined. Results showed that the aged PO had higher moisture content compared with the aged MO. However, the Kraft papers impregnated with PO had better tensile strength after 750 h of aging, which may be attributed to the affinity of PO to moisture. This slows down the hydrolytic degradation mechanism. In terms of colour, the Kraft papers were darker than their original colour as the tensile strength decreased. To conclude, the Kraft paper impregnated with PO had higher tensile strength compared with those impregnated with MO. [ABSTRACT FROM AUTHOR]

Mineral materials, such as corundum, quartz and periclase are very often used in technological processes. Due to its characteristics, and chemical reaction in solid state, these minerals form very interesting and useful material, cordierite. The mineral ratio in this compound (MgO : Al2O3 : SiO2) is 2:2:5. They form cordierite, electronic ceramic, which can be sintered in a narrow temperature range, at about 1375 °C. Composition of this electronic ceramics material is is 2MgO-2Al2O3-5SiO2 (MAS) and in this research 20% mass Bi2O3 was added in the aim of decrease the sintering temperature. The effects of sintering, the composition and morphology were followed by x-ray diffraction, scanning electron microscopy and EDS analysis, as a function of sintering temperature. MAS ceramics were sintered at 1000ºC, 1100ºC and 1200ºC.

Background: Re‐use of wastes as a part of sustainable development is one of the most important aspects of a healthy human life and environmental protection. This study examines the viability of using paper industry slag for the production of building ceramics. Results: Paper industry slag was used in the production of ceramic bricks as a burnable additive in amounts of 5, 10 and 15 wt%. The slag was introduced without and after three different preparatory operations: dried, dried and ground, granulated and dried. Clay was used as a raw material and quartz sand as a lean additive. The samples were made by plastic molding. Drying was carried out at a temperature of 100 °C. To determine the optimal heat treatment temperature, firing was carried out at 900, 950, 1000 and 1050 °C with holding at the maximum temperature for 30 min, followed by determination of the properties of the samples. Conclusions: It has been established that the samples obtained using the slag have good physical and mechanical properties and comply with current standards. At the same time, the use of slag in the production of ceramic bricks makes it possible to solve the problem of waste management, as well as to obtain a secondary material resource from the slag – a burnable additive, which leads to savings in raw materials and energy resources in the production of ceramic bricks. © 2022 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

The book "Western Ceramic Traditions: Prehistoric and Historic Native American Ceramics of the Western U.S." edited by Suzanne Griset explores the diversity of ceramic traditions and social identities reflected in pottery production in the far southwestern desert and coastal region of the U.S. The book features 11 chapters that critically examine traditional typologies of plainware pottery and explore new datasets for dating and identifying the composition of pottery. The volume provides important discussions on the sociocultural aspects of pottery technology and challenges the limitations of typological classification. The book is recommended for researchers working with plainware or other ceramic wares, although the technical ceramic data presented may be daunting for readers without an archaeological or ceramic analyst background. [Extracted from the article]

Fibers represent a type of structure of great interest in catalysis since they combine high area to volume ratio and can be fabricated from many types of materials, such as ceramic oxides, polymers, and alloys. They can be used in isolated form or structured, as in the case of the ceramic papers synthesized in this work, following a modified papermaking technique. The addition of cationic and anionic polyelectrolytes improved the retention of ceramic fibers during the ceramic paper formation stage by adsorption processes, through the formation of floccules. In the complex aqueous system containing charged macromolecules, the amounts of polyelectrolytes to be added were determined by titrations. To enhance mechanical properties of ceramic papers, different classes of nanoparticle suspensions can be used as binders. As a novel alternative, we have used different borate-type compounds. Among them, we selected natural ulexite, which was purified and used as a binder of ceramic fibers. In order to improve mechanical resistance and flexibility, measured from tensile indexes and elastic module, the amounts of NaCaB5O6(OH)6.5H2O and the calcination temperature were varied. In this contribution, to take advantage of the unique characteristics of the ulexite-containing ceramic papers, they were impregnated with Co,Ce and Co,Ba,K and tested for diesel soot combustion. [ABSTRACT FROM AUTHOR]

In this study, continuous carbon reinforced C f /(Ti 0.2 Zr 0.2 Hf 0.2 Nb 0.2 Ta 0.2)C–SiC high entropy ceramic matrix composites were additively manufactured through paper laminating (PL), direct slurry writing (DSW), and precursor infiltration and pyrolysis (PIP). (Ti 0.2 Zr 0.2 Hf 0.2 Nb 0.2 Ta 0.2)C high entropy ceramic (HEC) powders were synthesized by pressureless sintering and ball milling. A certain proportion of HEC powder, SiC powder, water, binder, and dispersant were mixed to prepare the HEC-SiC slurry. Meanwhile, BN coating was prepared on the 2D fiber cloth surface by the boric acid-urea method and then the cloth was cut into required shape. Additive manufacturing were conducted subsequently. Firstly, one piece of the as-treated carbon fiber cloth was auto-placed on the workbench by paper laminating (PL). Then, the HEC-SiC slurry was extruded onto the surface of the cloth by direct slurry writing (DSW). PL and DSW process were repeated, and a C f /HEC-SiC preform was obtained after 3 cycles. At last, the preform was densified by precursor infiltration and pyrolysis (PIP) and the final C f /HEC-SiC composite was prepared. The open porosity of the C f /HEC-SiC composites, with the HEC volume fractions of 15, 30 and 45%, were 7.7, 10.6, and 11.3%, respectively. And the density of the C f /HEC-SiC composites, with the HEC volume fractions of 15, 30 and 45%, were 2.9, 2.7 and 2.3 g/cm3, respectively. The mechanical properties of the C f /HEC-SiC composites increased firstly and then decreased with the HEC content increase, reaching the maximum value when the HEC volume fraction was 30%. The mechanical properties of the C f /HEC-SiC composites containing 45, 30 and 15% HEC were as follows: flexural strength (180.4 ± 14 MPa, 183.7 ± 4 MPa, and 173.9 ± 4 MPa), fracture toughness (11.9 ± 0.17 MPa m1/2, 14.6 ± 2.89 MPa m1/2, and 11.3 ± 1.88 MPa m1/2), and tensile strength (71.5 ± 4.9 MPa, 98.4 ± 12.2 MPa, and 73.4 ± 8.5 MPa). From this study, the additive manufacturing of continuous carbon fiber reinforced high entropy ceramic matrix composites was achieved, opening a new insight into the manufacturing of ceramic matrix composites. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cerium – Manganese Catalytic Ceramic Paper very active for soot oxidation. • Spray method showed to be efficient for anchoring catalytic species on fibers. • Experiments at bench scale showed good soot filtration capacities. • Citric Acid addition during impregnation improved catalytic distribution on fibers. Diesel Particulate filters are considered one of the most efficient technologies to reduce particulate matter emitted by diesel engines. In this paper we study the development of catalytic ceramic papers based on Mn-Ce and their applications as soot particle filters in bench scale tests. Ceramic papers were prepared by a dual polyelectrolyte papermaking method and were impregnated with Mn and Ce precursors through a wet-spray procedure using a commercial fogger. Catalytic ceramic papers were tested as catalysts for the combustion of soot, which was obtained both from the burning of diesel fuel and directly from a bench test. In addition, the filtering capacity of catalytic ceramic papers was tested through opacity measurements by placing the ceramic papers in a suitable case at the end of the engine. Mn-Ce based catalysts were active in the soot combustion. The addition of citric acid considerably improved the catalytic performance of all the systems studied. This beneficial effect of citric acid is related to an improvement in the distribution of the catalytic material onto the ceramic fibers, being the mixed equimolar oxide Mn-Ce the most active catalyst. [ABSTRACT FROM AUTHOR]

Cellulose is now considered as an appealing environment friendly material for the development of sustainable separators for rechargeable batteries. This study thus aims to develop high performance paper based ceramic separators with superior electrolyte wettability (>170 %), high thermal stability (>200 °C) and excellent flame safety. While developing paper based ceramic separator, extensive studies are carried out to understand thenature and functionality of different nano-structured ceramic materials (Al 2 O 3 , BaTiO 3 and ZrO 2) impregnated in paper matrix. Nano-ZrO 2 facilitates an effective pathway for Li +-ion transport (t Li + = 0.51), whereas BaTiO 3 and Al 2 O 3 ceramics show moderate Li +-ion transport properties (t Li+ of 0.29 and 0.30 respectively). Electrochemical Impedance Spectroscopy (EIS) measurement clearly reveals that ZrO 2 exhibits more interfacial compatibility with the electrodes (MCMB and LiNi 1/3 Mn 1/3 Co 1/3 O 2) compared to the other two ceramic separators during full cell operation. The developed paper separators show excellent electrochemical properties in terms of cycling (tested 300 cycles), multi-electrode compatibility and rate capabilities at different current densities of 0.1–1.2 mAcm−2. The pre- and post-electrochemical EIS data reveal that ZrO 2 based impregnation offers significantly lower charge transfer resistance compared to the other two separators. The study thus demonstrates a real promise for its successful application in Li-ion battery towards achieving sustainability and safety. [Display omitted] • Sustainable, flexible and high safety ceramic based paper separators for LIBs. • Separators were developed using easy to scale up wet-coating process. • Ceramic impregnation affects physical and electrochemical properties of the separators. • Paper separators show superior electrolyte wettability and high thermal stability. • Better electrochemical performances and flame safety are other important advantages. [ABSTRACT FROM AUTHOR]

Cellulose‐based paper samples were surface‐modified by a polymeric single‐source precursor prepared from perhydropolysilazane (PHPS) and iron(III)acetylacetonate (Fe(acac)3) and ammonolyzed at 500°C, 700°C, 900°C, and 1000°C, leading to C/SiFe(N,C)O‐based ceramic papers with in situ‐generated hierarchical micro/nano‐morphology. As reference, cellulose‐free samples were prepared under the same conditions. Upon thermal treatment, the microstructure evolutions of the resulting ceramic paper and the reference sample were comparatively investigated. Scanning electron microscopy (SEM) showed that for all temperatures, the ceramic papers exhibit the same morphology as the template, however, with noticeable shrinkage and curling, particularly evident at higher temperatures. X‐ray diffraction (XRD) measurements of the reference samples and the ceramic papers showed a similar crystallization behavior and phase evolution in both materials. In the ceramic paper, the crystallization process seems to occur at a later time. The results provide a comprehensive understanding of the investigated C/SiFe(N,C)O‐based ceramic system. It was shown that use of the cellulose‐based paper template has the benefit of retaining the microstructure and furthermore, apart from transforming the cellulose fibers into turbostratic carbon, does not change the phase evolution during the polymer‐to‐ceramic transformation, allowing at the same time the manufacturing of novel morphologically complex parts by a convenient one‐pot synthesis approach. [ABSTRACT FROM AUTHOR]

Ag@ceramic composite papermaking pigment was prepared by coating silver onto red ceramic powder using the electroless plating method. SEM and XRD showed that the ceramic pigments have a porous crystalline structure and that silver particles had been successfully loaded onto the surface and into the pores of the Ag@ceramic. Untreated ceramic pigment and Ag@ceramic pigment were incorporated into paper sheets by coating, filling and filling‐coating. Using spinach as an example, the ability of the different papers to preserve food was then evaluated. Four indicators were used to assess the preservative effect of the papers: inhibition of growth of Staphylococcus aureus and Escherichia coli, weight loss of the spinach and retention of vitamin C and chlorophyll in the spinach. Although the ceramic preservative paper has no antibacterial properties, it reduced weight loss from the spinach and increased retention of vitamin C and chlorophyll. The antibacterial preservative papers inhibited the growth of E. coli and S. aureus by >99%, and because of their additional antibacterial activity, these papers preserved the spinach more effectively. The experimental results showed that the antibacterial food‐preservative paper incorporating ceramic pigments had great potential in food packing applications. [ABSTRACT FROM AUTHOR]

This paper describes the fabrication and characterization of novel preceramic paper-derived functionally graded materials (FGMs) based on Ti 3 (Si,Al)C 2 MAX phase. The FGMs with different architecture were fabricated via spark plasma sintering of stacked preceramic papers at 1250 °C for 5 min. Microstructure, phase composition and elemental distribution were analyzed by scanning electron microscopy, X-ray diffraction and energy-dispersive X-ray spectroscopy, respectively. Oxidation tests were performed in air at 1300 °C for 5 h. FGMs containing Al- and Si-enriched MAX-phase layers were formed. The fabricated materials exhibit high flexural strength (over 600 MPa), which are dependent on microstructure and composition of individual layers as well as the architecture of composites. It was found that texturing of MAX phase grains during SPS results in anisotropic hardness of the composite. The difference in the composition of the individual layers also provides a hardness gradient in the composite. It was shown that the formation of the outer layer from the Al-enriched Ti 3 Al(Si)C 2 MAX phase increases the corrosion resistance of Ti 3 SiC 2 -based composites. The high corrosion resistance of FGMs is due to the growth of a continuous and dense Al 2 O 3 oxide layer. [ABSTRACT FROM AUTHOR]

SiFeO(N,C)‐based ceramic papers were prepared via a one‐pot synthesis approach by dip‐coating a cellulose‐based paper template with a polymeric perhydropolysilazane precursor modified with iron(III)acetylacetonate. The preceramic composites were subsequently pyrolyzed in ammonia atmosphere at 500, 700, and 1000°C, respectively, and the characteristics of the three resulting ceramic papers were comparatively investigated. Scanning electron microscopy revealed that in each sample, the morphology of the template is successfully transferred on the ceramic system, with the cellulose‐derived fibers being converted to elemental carbon encased by a SiFeO(N,C) coating. Electron transparent cross‐sectional samples for transmission electron microscopy (TEM) were prepared from the ceramic papers, employing a standard ultramicrotomy slice cutting procedure, allowing for a detailed characterization of their in situ generated micro‐/nanostructure as well as occurring crystalline phases. TEM imaging and diffraction revealed that depending on pyrolysis temperature a different microstructure with a distinct phase assemblage is generated in the polymer‐derived ceramic papers. Crystallization from the polymer precursor starts with the precipitation of wüstite (Fe(1‐x)O) nanoparticles at 700°C inside the ceramic coating and secondary ε‐FexN at the fiber‐coating interface. Upon pyrolysis at 1000°C however, the sample primarily accommodates metallic α‐iron nanocrystals that impart ferromagnetic characteristics to the ceramic paper. The results show that the template‐assisted polymer‐derived ceramic route is a feasible approach in the production of complex ceramic compounds with fibrous paper‐like morphology. By adjusting the pyrolysis temperature, microstructure and phase composition of the ceramic paper can be conveniently tailored to the needs of its respective application. [ABSTRACT FROM AUTHOR]

Zirconia implants are gaining attention as a viable alternative to titanium implants due to their comparable osseointegration development, improved soft tissue adaptation, and enhanced aesthetics. An encouraging avenue for improving zirconia implant properties involves the potential application of bioactive coatings to their surfaces. These coatings have shown potential for inducing hydroxyapatite formation, crucial for bone proliferation, and improving implant mechanical properties. This study aimed to evaluate the effect of coating zirconia implants with two bioactive glasses, 45S5 and BioK, on osteogenesis in vitro and osseointegration in vivo. Zirconia samples and implants were prepared using Zpex zirconia powder and blocks, respectively. The samples were divided into three groups: polished zirconia (ZRC), zirconia coated with 45S5 bioglass (Z + 45S5), and zirconia coated with BioK glass (Z + BK). Coatings were applied using a brush and sintered at 1200°C. Chemical analysis of the coatings was carried out using x-ray diffraction and Fourier Transform Infrared Spectroscopy. Surface topography and roughness were characterized using scanning electron microscopy and a roughness meter. In vitro experiments used mesenchymal cells from Wistar rat femurs, and the coated zirconia implants were found to promote cell viability, protein synthesis, alkaline phosphatase activity, and mineralization, indicating enhanced osteogenesis. In vivo experiments with 18 rats showed positive results for bone formation and osseointegration through histological and histomorphometric analysis and a push-out test. The findings indicate that bioactive glass coatings have the potential to improve cell differentiation, bone formation, and osseointegration in zirconia implants., (© 2024 Wiley Periodicals LLC.)

Pottery making in technology education aims to foster students' practical and creative ability. In a typical pottery making class, students receive the teacher's instruction on the fundamental techniques used in pottery making and have opportunities to practice. It is meaningful to construct an observation-doing-reflection process for students in a pottery making class to promote their learning experience and performance. Therefore, in this study, a Virtual Reality (VR)-based pottery making approach was applied to technology education in a junior high school to examine its effects on students' creativity and learning engagement. A total of 97 seventh graders from three classes participated in pottery making in class. One class of 34 students was assigned to be the experimental group learning with the VR-based approach, while the other two classes were assigned to be the control groups, with 30 students learning with the paper-and-pencil approach and 33 students with the clay-based approach. The results showed that the students learning with the VR-based approach were not only more creative in terms of their products, but also had higher cognitive engagement than those in the control groups. Moreover, the VR-based approach improved the students' behavioral, emotional and social engagement compared to the paper-and-pencil approach.

Two commercial stoneware pastes traditionally used to produce ceramic objects were evaluated. The objective was the comparative characterization of the pastes and to find the most suitable to obtain fine ceramic objects using the pottery wheel. Both ceramic pastes were characterized by X-ray powder diffraction (XRPD), particle size analyses (laser diffraction) and thermal analyses (thermogravimetry-TG, its derivative-DTG, and differential thermal analysis-DTA). The technological properties like linear drying and firing shrinkage, moisture content and plasticity were also determined. The results showed that both pastes have appropriate properties making them suitable for plastic shaping by pottery wheel. In addition, the stoneware paper clay paste is "greener" due to its content of cellulose fibers which can come even from recycled paper. [ABSTRACT FROM AUTHOR]

The use of the ornamental stone wastes, such as the originated from granite or marble, has been the subject of technological studies that evaluated its application in ceramic and cement materials; however, some complementary assessments, such as its life cycle assessment, are still not well explored in the literature. Therefore, the objective of this study was to discuss the main environmental impacts related to the manufacture of ceramic specimens, comparing conventional production versus the production of specimens incorporated with ornamental stone wastes. For this, the life cycle assessment was conducted in accordance with ISO 14.040 and 14.044. For this research, the ornamental stone wastes from the municipality of Cachoeiro do Itapemirim-ES and clay from the municipality of Campos dos Goytacazes-RJ were used. The system was modeled, using the SimaPro 9.0 software and the Ecoinvent database 3.3, for the life cycle assessment of the ceramic specimens and the potentiality regarding the use of ornamental stone wastes in ceramic materials using alternative input energy for burning, contributing to the effectiveness of the solid wastes reuse by the ceramic industry. The evaluation identified that the ornamental stone wastes incorporated into the ceramic specimens had significant potential in reducing environmental impacts and that the alternative input energy in burning stage makes them even more relevant. The study points out as the main result, the reduction of 35.74% of the impacts related to the category of the emission of greenhouse gases, and scarcity of mineral resources, 14.83% reduction, when compared to specimens to conventional brick production and alternative brick production, which emphasizes that the ceramic materials with wastes contribute to the mitigation of impacts., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

My comments concern the severe errors in the crystallographic part of the commented paper. The correct formula is proposed to be Bi1–xYxFeO3 ('Bi0.85Y0.15FeO3') instead of BiFe0.85Y0.15O3. It is found that the studied sample is bi-phasic with nearly equal amounts of BiFeO3:Y and Bi25FeO39:Y. The actual composition of the studied crystals is not known. Moreover, the type of unit cell is not correct. [ABSTRACT FROM AUTHOR]

[Display omitted] • A route is proposed to load nanoparticles and electrolyte into ceramic paper separator. • The proposed route is efficient and safe, which can be promoted to used in large scales. • Electrochemical performance of thermal batteries can be obviously improved with ceramic paper as separator. Composites consisted of ceramic paper, nanoparticles as well as molten salt electrolyte, are developed as the new electrolyte separators to substitute the traditional ones in thermal batteries, due to their flexible manufacture and good exhibition in electrochemical performance. However, the existed methods for fabricating the composites by roughly dip-coating with aqueous solutions, are suffering from drawbacks such as inefficiency, low consistence, or high temperature risk. Therefore, a new approach based on a melting-absorption-diffusion process, by using precursors without solvent, is developed. Firstly, the salts are accurately weighted. Then they melt on surfaces of ceramic papers and diffuse inside. After being treated at appropriate temperature for hours, high quality electrolyte separators based on ceramic papers are achieved. Compared to the traditional approaches, the new method can obviously increase and accurately control the amount of loaded nanoparticles and molten salts for each time. The achieved electrolyte separators also exhibit good electrochemical performance in single cells of thermal batteries compared with the traditional ones. With advantages like easy operation, high efficiency, and improved performance, this melting and in situ loading method holds broad prospect in preparing electrolyte separators at large scale. [ABSTRACT FROM AUTHOR]

Objective: The background and clinical understanding of the properties of currently available indirect restorative systems and fabrication methods is, along with manufacturer and evidence-based literature, an important starting point to guide the clinical selection of materials for tooth and/or implant supported reconstructions. Therefore, this review explores most indirect restorative systems available in the market, especially all-ceramic, along with aspects of manufacturing process, clinical survival rates, and esthetic outcomes., Overview: Progressive incorporation of new technologies in the dental field and advancements in materials science have enabled the development/improvement of indirect restorative systems and treatment concepts in oral rehabilitation, resulting in reliable and predictable workflows and successful esthetic and functional outcomes. Indirect restorative systems have evolved from metal ceramics and polymers to glass ceramics, polycrystalline ceramics, and resin-matrix ceramics, aiming to improve not only biological and mechanical properties, but especially the optical properties and esthetic quality of the reconstructions, in attempt to mimic natural teeth., Conclusions: Based on several clinical research, materials, and patient-related parameters, a decision tree for the selection of indirect restorative materials was suggested to guide clinicians in the rehabilitation process., Clinical Significance: The pace of materials development is faster than that of clinical research aimed to support their use. Since no single material provides an ideal solution to every case, professionals must continuously seek information from well designed, long-term clinical trials in order to incorporate or not new materials and technological advancements., (© 2023 Wiley Periodicals LLC.)

In this study, additive-manufactured silicon carbide preforms were joined and densified by reaction bonding via liquid silicon infiltration. The silicon carbide preforms were first printed by binder jetting additive manufacturing. To demonstrate concurrent joining and densification, two preforms with carbon or parchment papers at the interface were concurrently joined and infiltrated by liquid silicon. Results showed a robust interface with thicknesses ranging from 150 to 500 µm, depending on the paper type and the number of paper layers. High-energy synchrotron X-ray revealed that β-phase silicon carbide was formed inside the interface. Finally, two additively manufactured samples with complicated channel geometry were successfully joined. Energy dispersive spectroscopy of the interface of the channeled samples showed a consistent and robust joining. This concurrent approach of joining and densification enables efficiency improvement of fabricating silicon carbide parts with complicated geometries and widens geometry freedom for additive manufacturing of silicon carbide. [ABSTRACT FROM AUTHOR]

With the increasing demand for the resilient capacity of transformers in high-proportion renewable energy grids, the overload capacity of transformers and the thermal conductivity of winding insulation materials have been put forward as important requirements. In response to these requirements, a novel ceramic high temperature tolerance insulation winding is proposed in this paper and is applied in a ceramic insulated winding transformer. A combination of simulation and experimentation is used to analyze the thermal-flow characteristics of this transformer. The temperature and flow field distribution characteristics of transformers with both winding insulation methods (ceramic and Nomex paper) are compared. The internal mechanism of reflux near the iron core and high voltage winding under forced air cooling is clarified. A superior outside cooling condition is obtained. A prototype ceramic insulated winding transformer is developed and tested to verify the accuracy of the simulation model. The results show that the hotspot temperature of the ceramic insulated winding transformer under natural cooling is 10.7% lower than that of the Nomex paper insulated winding transformer. With forced air cooling of 2, 3, 4, 5, and 6 m/s applied at the bottom, the hotspot temperature of the ceramic insulated winding transformer is 11.4%, 10.5%, 9.7%, 14.0%, and 17.8% lower than that of the Nomex paper insulation winding transformer, respectively. Under forced air cooling, a reflux phenomenon is observed in both transformers in the vicinity of the iron core and high voltage winding due to the formation of adverse pressure gradient region and wall viscous force blocking. The strength of the reflux is affected by the magnitude of the forced air cooling flow velocity and the construction of the transformer. The optimal range of the external cooling flow velocity for the ceramic insulated winding transformer is 3–4 m/s. The errors between the simulated temperature and the measured temperature at the nine monitoring points of the prototype are all less than 5%, which verifies the effectiveness of the simulation model. The experimental and theoretical basis for the design and application of resilient capacity dry type transformers is provided by this research. [ABSTRACT FROM AUTHOR]

My comments concern the significant error in the crystallographic part of the commented papers. It was discovered that the studied nanocrystals are of sillenite type and the correct formula should be Bi 25 FeO 39 :Co,Ti and Bi 25 FeO 39 :Ni,Ti instead of BiFeO 3. Moreover, the type of unit cell is not correct. Due to the doping the new type of unit cell, previously unknown, was proposed for such crystals. It was found that the studied sample contains two slightly different phases of the sillenite type. The actual chemical composition of the studied crystals is not known. [ABSTRACT FROM AUTHOR]

My comments concern the significant errors in the crystallographic part of the commented paper. [ABSTRACT FROM AUTHOR]

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