Production of NiO,NiO/Ag,NiO/Au,and NiO/Pt hollow spheres by using block copolymer stabilized microspheres as a template

Hollow spheres of nickel oxide (NiO) and silver, gold, and platinum nanoparticle loaded NiO composites were successfully produced by using polystyrene (PS) latexes as hard template. Due to the presence of tertiary amine based diblock copolymer stabilizer on the surface of PS, the tertiary amine functional groups provided homogene deposition of nickel hydroxide, and then the precursor NiO salt production on the surface of PS latexes with a controlled precipitation technique. Then, NiO and NiO/metal NP hollow spheres were produced by calcination at 600 °C. Thermogravimetric analysis indicated that the amounts of NiO and NiO-composite after calcination were in the range of 21.1–29.7 wt%. The diameters of metal oxide spheres were in the range of 2.0–2.7 μm and the shell thickness were in the range of 250–350 nm. These structures had very low densities due to their porous and hollow structures and had outer layers with highly rough surfaces due to formation of nanosheets, which may offer important advantages for catalysis studies.     

Effects of annealing at high pressure on structure and mechanical properties of Al87Ni7Gd6 metallic glass

The effects of annealing and annealing with a superimposed pressure of 940 MPa on the primary crystallization behaviour of α-Al and the resulting micro-hardness have been studied for as-quenched Al₈₇Ni₇Gd₆ metallic glass. Isothermal annealing experiments were conducted for 30 min at 188 °C, 191 °C, and 205 °C in silicone oil maintained either at atmospheric pressure (i.e. 0.1 MPa) or at 940 MPa. XRD analyses detected the evolution of structure with annealing at 0.1 MPa, while specimens annealed with 940 MPa pressure exhibited sharper diffraction peaks than those annealed at 0.1 MPa. DSC measurements were conducted on the as-received amorphous ribbons as well as ribbons annealed at different temperatures at either 0.1. MPa or with 940 MPa superimposed pressure. Specimens annealed with 940 MPa pressure exhibited higher onset temperatures (i.e. T_x1) and temperatures for the first exothermic peak (i.e. T_p1) for primary crystallization. TEM measurements revealed an increase in the volume fraction of α-Al with increases in annealing temperature, while micro-hardness measurements revealed an increase in hardness with increasing amounts of α-Al. Specimens annealed with 940 MPa pressure exhibited further increases in both the volume fraction of α-Al and resulting micro-hardness.     

Analysis of performance for centrifugal steam compressor

In this study, mean streamline and Computational fluid dynamics (CFD) analyses were performed to investigate the performance of a small centrifugal steam compressor using a latent heat recovery technology. The results from both analysis methods showed good agreement. The compression ratio and efficiency of steam were found to be related with those of air by comparing the compression performances of both gases. Thus, the compression performance of steam could be predicted by the compression performance of air using the developed dimensionless parameters.     

Application of physical vapor deposition process to modify activated carbon fibers for ozone reduction

This study utilized the activated carbon fiber (ACF) modified with metal catalyst via physical vapor deposition (PVD) process (ACF/PVD) to diminish ozone. Furthermore, the ozone removal efficiency of ACF/PVD was compared with that of original ACF and ACF modified with metal catalyst via impregnation process (ACF/impregnation). In addition to the kinds of coated metal and the inlet ozone concentrations, the effects of the coating thickness and the reaction temperature on ACF/PVD for ozone removal were also examined. The results indicate that the ozone removal efficiency of ACF/PVD is better than that of original ACF and ACF/impregnation. The ozone removal efficiency of different metal-coated ACF/PVD in the superior order is gold (Au), and manganese (Mn). The increase of Au-coated thickness (3 nm to 80 nm) on ACF/PVD will enhance the ozone removal. However, when the Mn-coated thickness on ACF/PVD is larger than 15 nm, the ozone removal efficiency displays a declining trend. Furthermore, a higher reaction temperature will result in a better ozone removal of ACF/PVD and the original ACF.     

P(VDF–HFP)/BST纳米复合薄膜的制备及介电、储能性能

采用溶液铸造法,以聚(偏氟乙烯-六氟丙烯)[P(VDF-HFP)]为基体、钛酸钡锶(BST)为填料制备了纳米薄膜材料.对薄膜的物相组成和微观形貌进行了表征,研究了BST含量对薄膜介电性能和储能性能的影响.结果表明,随着BST含量的增大,薄膜的介电常数显著上升,介电损耗在中、高频区域有所下降,击穿强度逐渐减小,薄膜的充电...     

Effect of solution concentration on the surface properties of Y2O3 solution-coated film on flexible Metal Substrate

In order to investigate the effect of solution concentration on the surface properties of Y₂O₃ films dipcoated on a flexible metal substrate, films were coated on unpolished Hastelloy substrate followed by a heat treatment process to convert the film to amorphous Y₂O₃. Solutions of different molarities were used to deposit films with different thicknesses, and the surface smoothness and morphologies were investigated. The thickness of the film increased along with the molarity of the coating solution. The rate of improvement of the smoothness was fast when solutions of high molarity were used; this rate improvement can help reduce the number of coatings needed to reach the desired level of smoothness. It was found that multiple coated Y₂O₃ film has a smooth surface because the film covers up the irregular surface contours of the substrate.     

Enhancement of surface quality in ultrasonic machining of glass using a sacrificing coating

We present a new fabrication method that enables precision hole machining to be achieved by sacrificing the coating on the substrate in ultrasonic machining (USM). A hard wax coating is deposited on the glass substrate, and holes are precisely fabricated in the coated glass using USM. Finally, a wax coating is removed using a cleaning process. The wax coating protects the surface of the glass so that cracks are generated in the wax rather than on the surface. The surface accuracy of the glass substrate is evaluated at the hole entrance using the new tools in USM as a function of the thickness of the coating. The entrance diameters of the machined holes and the machining forces at the beginning of cutting are measured as a function of the thickness of the coating. The entrance cracks and out-of-roundness of the machined holes are generated in the sacrificed coating on the glass substrate; hence, the surface quality of the glass holes is enhanced in USM.     

Contribution of Invariant Natural Killer T Cells to the Clearance of Pseudomonas aeruginosa from Skin Wounds

Chronic infections are considered one of the most severe problems in skin wounds, and bacteria are present in over 90% of chronic wounds. Pseudomonas aeruginosa is frequently isolated from chronic wounds and is thought to be a cause of delayed wound healing. Invariant natural killer T (iNKT) cells, unique lymphocytes with a potent regulatory ability in various inflammatory responses, accelerate the wound healing process. In the present study, we investigated the contribution of iNKT cells in the host defense against P. aeruginosa inoculation at the wound sites. We analyzed the re-epithelialization, bacterial load, accumulation of leukocytes, and production of cytokines and antimicrobial peptides. In iNKT cell–deficient (Jα18KO) mice, re-epithelialization was significantly decreased, and the number of live colonies was significantly increased, when compared with those in wild-type (WT) mice on day 7. IL-17A, and IL-22 production was significantly lower in Jα18KO mice than in WT mice on day 5. Furthermore, the administration of α-galactosylceramide (α-GalCer), a specific activator of iNKT cells, led to enhanced host protection, as shown by reduced bacterial load, and to increased production of IL-22, IL-23, and S100A9 compared that of with WT mice. These results suggest that iNKT cells promote P. aeruginosa clearance during skin wound healing.     

Inhibition of Aberrant α(1,2)-Fucosylation at Ocular Surface Ameliorates Dry Eye Disease

Fucosylation is involved in a wide range of biological processes from cellular adhesion to immune regulation. Although the upregulation of fucosylated glycans was reported in diseased corneas, its implication in ocular surface disorders remains largely unknown. In this study, we analyzed the expression of a fucosylated glycan on the ocular surface in two mouse models of dry eye disease (DED), the NOD.B10.H2^b mouse model and the environmental desiccating stress model. We furthermore investigated the effects of aberrant fucosylation inhibition on the ocular surface and DED. Results demonstrated that the level of type 2 H antigen, an α(1,2)-fucosylated glycan, was highly increased in the cornea and conjunctiva both in NOD.B10.H2^b mice and in BALB/c mice subjected to desiccating stress. Inhibition of α(1,2)-fucosylation by 2-deoxy-D-galactose (2-D-gal) reduced corneal epithelial defects and increased tear production in both DED models. Moreover, 2-D-gal treatment suppressed the levels of inflammatory cytokines in the ocular surface and the percentages of IFN-γ⁺CD4⁺ cells in draining lymph nodes, whereas it did not affect the number of conjunctival goblet cells, the MUC5AC level or the meibomian gland area. Together, the findings indicate that aberrant fucosylation underlies the pathogenesis of DED and may be a novel target for DED therapy.