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SiC composite ceramics for solar absorber and storage integration are new concentrating solar power materials. SiC composite ceramics for solar absorber and storage integration were fabricated using SiC, black corundum and kaolin as the raw materials, Co2O3 as the additive via pressureless graphite-buried sintering method in this study. Influences of Co2O3 on the microstructure and properties of SiC composite ceramics for solar absorber and storage integration were studied. The results indicate that sample D2 (5wt% Co2O3) sintered at 1 480 °C exhibits optimal performances for 119.91 MPa bending strength, 93% solar absorption, 981.5 kJ/kg (25–800 °C) thermal storage density. The weight gain ratio is 12.58 mg/cm2 after 100 h oxidation at 1 000 °C. The Co2O3 can decrease the liquid phase formation temperature and reduce the viscosity of liquid phase during sintering. The liquid with low viscosity not only promotes the elimination of pores to achieve densification, but also increases bending strength, solar absorption, thermal storage density and oxidation resistance. A dense SiO2 layer was formed on the surface of SiC after 100 h oxidation at 1 000 °C, which protects the sample from further oxidation. However, excessive Co2O3 will make the microstructure loose, which is disadvantageous to the performances of samples. [ABSTRACT FROM AUTHOR]

In order to study the performance and feasibility of magnesia‐alumina spinel (MgAl2O4) ceramics for thermal storage in solar thermal power generation, MgAl2O4 was prepared by theoretical composition using α‐Al2O3 as aluminium source, fused magnesia, magnesite, and light burned magnesia as different magnesium sources and kaolin as additive. The effects of magnesium source and the additive on sintering properties, thermal shock resistance and thermal properties of MgAl2O4 ceramics were researched. The results shown sample A1 (with fused magnesia) sintered at 1670°C possessed the optimum comprehensive properties, the bending strength increased by 7.71% after 30 thermal shock times (room temperature‐1000°C, air cooling), the specific heat capacity was 1.05 J/ (g·K). Therefore, the MgAl2O4 ceramics exhibited great potential in high‐temperature thermal storage material. [ABSTRACT FROM AUTHOR]

Mullite thermal storage ceramics were prepared by low-cost calcined bauxite and kaolin. The phase composition, microstructure, high temperature resistance and thermophysical properties were characterized by modern testing techniques. The experimental results indicate that sample A3 (bauxite/kaolin ratio of 5:5) sintered at 1 620 °C has the optimum comprehensive properties, with bulk density of 2.83 g·cm−3 and bending strength of 155.44 MPa. After 30 thermal shocks (1 000 °C-room temperature, air cooling), the bending strength of sample A3 increases to 166.15 MPa with an enhancement rate of 6.89%, the corresponding thermal conductivity and specific heat capacity are 3.54 W°(m°K)−1 and 1.39 kJ°(kg°K)−1 at 800 °C, and the thermal storage density is 1 096 kJ°kg−1 (25–800 mullite ceramics; sintering properties; high-temperature thermal storage; thermal shock resistance). Mullite forms a dense and continuous interlaced network microstructure. which endows the samples high thermal storage density and high bending strength, but the decrease of bauxite/kaolin ratio leads to the decrease of mullite content, which reduces the properties of the samples. [ABSTRACT FROM AUTHOR]

Selecting suitable ceramic powders for the preparation of UV‐curable ceramic suspensions, which are well suited for printing processes and production of high‐performance ceramic components, is a crucial factor in the practical industrial application of digital light processing (DLP) stereolithography. Therefore, this study aims to provide a comprehensive evaluation of alumina ceramic parts fabricated via DLP stereolithography using a variety of alumina powders with varying sizes and morphologies. Experiments were conducted to examine the rheological response, recoating performance, and curing behavior of UV‐curable alumina suspensions. Additionally, the thermal decomposition behavior of three‐dimensional (3D)‐printed green‐bodies, as well as the physical and mechanical properties of 3D‐printed sintered alumina components were thoroughly investigated. The best physical and mechanical performances were achieved by printing 55 vol% suspensions prepared using near‐spherical AA04 alumina powders (median diameter.4 μm). This study elucidates the effects of ceramic particle size and morphology on the entire technological process of DLP‐based ceramic stereolithography, thereby establishing the guidelines for the fabrication of high‐performance 3D‐printed ceramic objects in industrial and engineering production by selecting appropriate ceramic powders. [ABSTRACT FROM AUTHOR]

We used different SiC particle size as raw materials and via reaction bonding technique to prepare porous SiC membrane supports. The phase composition, microstructure, bending strength, open porosity, and pore size distribution were investigated as a function of SiC particle size and firing temperature. It is found that the reduction of SiC particle size not only dramatically enhances the bending strength of porous SiC membrane supports, but also slightly reduces the firing temperature duo to smaller SiC particle with higher specific surface area and higher reaction activity. Besides, the open porosity and pore size distribution are dependent on the firing temperature, but insensitive to the SiC particle size due to the pore related characters mainly controlled by the binder. The bending strength increases with the increasing of the firing temperature and with the decreasing of SiC particle size. When the firing temperature was 1 500 °C and SiC average particle size was 447.75 µm, the optimal performance were achieved, the bending strength was 15.18 MPa, the open porosity was 36.02 %, the pore size distributed at 3.09–112.47 µm, and the mean pore size was 14.16 µm. [ABSTRACT FROM AUTHOR]

Pristimerin has been shown to possess antiinflammatory activity. However, its potential use for asthma induced by airway inflammation has not yet been studied. First, we established a ovalbumin (OVA)-induced allergic asthma mice model. BALB/c mice were immunized and challenged by OVA. Treatment with pristimerin caused a marked reduction in the levels of OVA-specific IgE, immune cells, and IL-4, IL-5, IL-13 secretion. Histological studies using H&E staining were used to study the alterations in lung tissue. These results were similar to those obtained with dexamethasone treatment. We then investigated which signal transduction mechanisms could be implicated in pristimerin activity by Western blot. The data showed that pristimerin could inhibit MAPKs and NF-κB inflammatory pathways. [ABSTRACT FROM PUBLISHER]