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Highly transparent Y2O3 ceramics using TiO2 as an additive were synthesized by presintering and hot isostatic pressing (HIP). The effects of TiO2 contents and sintering conditions on the optical properties of the final transparent ceramics were investigated. A small amount (0.04‐0.16 wt%) may decrease the densification temperature by about 200°C. The Y2O3 ceramics doped with 0.16 wt% TiO2 revealed a transparency of 82% in the wavelength range 1‐6 μm. The thermal conductivity of the samples is about 11.8 W/m K at 25°C, which is close to that of the undoped Y2O3 ceramics. [ABSTRACT FROM AUTHOR]

Introduction:Amomum villosum Lour., a herbaceous plant in the ginger family, has been proven to be effective in treating gastrointestinal diseases. It has been listed in the Chinese Pharmacopeia as a legal source of Amomi Fructus. In our previous study, we demonstrated that treatment with extracts of A. villosum prevented the development and progression of intestinal mucositis. In the current study, we aimed to verify and explain the potential beneficial effects of A. villosum on inflammatory bowel disease (IBD). Methods: The effect of water extracts (WEAV) and volatile oil of A. villosum (VOAV) were evaluated on the immunological role of T lymphocytes and intestinal microecology in IBD rats induced with 2,4,6-trinitrobenzenesulfonic acid (TNBS). Body weight, food intake, colon length/weight, and disease activity index (DAI) as well as tissue damage scores were evaluated. The inflammatory response to IBD was assessed by measuring the expression of myeloperoxidase, interleukin (IL)-17 (IL-17), interferon-γ (IFN-γ), IL-10, tumor necrosis factor-α (TNF-α), and transforming growth factor-β (TGF-β). The percentage of regulatory CD4+ T cells in rat spleen was measured by flow cytometry and effects on the microbial community were evaluated by 16S rDNA gene sequencing. Results: All TNBS-induced rats showed typical clinical manifestations of IBD. IBD rats in the WEAV and VOAV treatment groups were effective in relieving body weight and appetite loss. Middle and high dosage of VOAV and WEAV significantly reduced the DAI, and tissue damage scores, whereas colon weight/length ratio was increase. All rats in the WEAV and VOAV groups showed significantly decreased IFN-γ levels and increased levels of IL-10 and TGF-β. Moreover, we observed that the percentage of regulatory CD4+ T cells was significantly enhanced during treatment with WEAV. In addition, administration of WEAV and VOAV effectively inhibited the release of enterogenic endotoxin, increased short-chain fatty acid-producing bacteria belonging to Firmicutes and Bacteroidetes, and decreased the abundance of Proteobacteria. Conclusion: Treatment with WEAV and VOAV significantly attenuated intestinal inflammation in IBD rats, which was possibly associated with its regulation on inflammatory cytokine and CD4+CD25+FOXP3+ T cells. Moreover, WEAV and VOAV may help maintaining the balance of intestinal microecology. [ABSTRACT FROM AUTHOR]

Transparent glass-ceramics containing Er3+:CaF2 crystallites were prepared with the co-firing method. The formation process of the glass-ceramics was investigated by means of SEM, XRD, and DSC. The results reveal that the Er3+:CaF2 nanocrystals do not dissolve into the fluorophosphates ( FP) glassmelt until the co-firing temperature increase higher than about 920°C. Below this temperature, Er3+:CaF2 survives the co-firing process and the nanocrystals just grow to spherical crystals of micrometers in size. Co-firing temperature higher than this temperature leads to the dissolution of Er3+:CaF2 and the dissolved Er3+:CaF2 recrystallized during quenching process and takes the shape of dendrite. [ABSTRACT FROM AUTHOR]

Strontium fluorapatite particles with tunable morphologies and geometries were successfully synthesized via a precipitation system by adjusting the pH value and temperature. Several analysis techniques were used to investigate and characterize the particles. The surface energy was calculated using first-principle calculations based on density functional theory. Capsule-like nanosized primary grains with axial growth directions parallel to the c-axis were synthesized at higher pH values, resulting from the difference in surface energy for the different planes of the Sr5( PO4)3F lattice. Bundle-like clusters were obtained at a pH value of ~7, which was attributed to a combination of the difference in surface energy and the phenomenon of heterogeneous nucleation occurring at low degrees of supersaturation. The study determined the approaches necessary to manufacture Sr5( PO4)3F powders with specific characteristics for different applications. [ABSTRACT FROM AUTHOR]

A common-rail system is widely used in electronically controlled diesel engines and has been used in Euro IV diesel engine development, as its consistency between the fuel injection quantities of the injectors can be controlled accurately. In Chinese home-made common-rail systems, the bottleneck is mainly caused by the mechanical manufacturing, which results in variation in the fuel injection quantity of different injectors. In spite of the low-class hardware limit, this paper introduces a software method to correct the inconsistency between the fuel injection quantities of the injectors over the whole range during which the engine is running. First, the main factor affecting the inconsistency between the fuel injection quantities of the injectors is determined on the basis of a series of experiments. Second, an optimization algorithm based on the start of injection is proposed to compensate for the difference between the injectors. Finally, the algorithm is verified on an EFS 8246 fuel-pump-testing platform and further on a YC6A diesel engine. The experiments demonstrate that the correction based on the start of injection not only can reduce the inconsistency between the fuel injection quantities of the injectors but also can improve both the idling control and the emission performance for the electronically controlled diesel engine. This paper also provides a successful example for improving the consistency between the fuel injection quantities from cylinder to cylinder in an electronically controlled diesel engine by this software optimization method. [ABSTRACT FROM AUTHOR]