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ZrO2/Al2O3porous ceramics were prepared by gel-foaming technique. The rheological property of slurry, the effect of solid content on the microstructure and mechanical property of the porous green bodies and the relationship between the MgO sintering additive content with the compressive strength and porosity of porous ceramics were investigated. The results show when the dispersant content is 0.4%(mass fraction), ball milling time is 4 h and the pH value is 4, the low viscosity is conductive to gelcasting. The porosity of green body reduces with the increase of solid content. The excessive solid content makes the slurry hard to flow, and the big pores and cracks form during gelcasting process, then the compressive strength of green body decreases. The mechanical properties of porous ceramics are improved with the phase transformation and micro-crack toughening induced by the ZrO2. The densification of pore supports increases, the porosity reduces and compressive strength increases with the increase of sintering additive content. The highest compressive strength is 30 MPa. The porous ceramics with appropriate porosity and high compressive strength can be prepared by introducing suitable contents of ZrO2 and sintering additive.

Aiming at the insulator sheds' dropping off, study on image threshold segmentation, edge detection, insulator recognition and fault diagnosis were carried out, characteristics of insulator and the background area were summarized, a new method to recognize and diagnose fault insulator was proposed. The OTSU was applied for image segmentation, and wavelet modulus maximum method for edge detection, Hough transform was improved to detect ellipsis quickly, ellipse parameters were used to design the classification standards and accurately recognize the insulator. Finally, fault diagnosis was realized based on location information. The method was verified using aerial images. The results indicate that ellipse parameters can be calculated, functions such as edge detection, insulator recognition, and fault diagnosis can be realized, and the algorithm responds quickly and accurately. [ABSTRACT FROM AUTHOR]

Invasive plants can inhibit the survival and reproduction of native species through alle-lopathy. It is not clear whether the native plants, especially the mosses in the ground layer, inf-luence the invasive plants. In this study, we examined the effects of two native moss species, Brachythecium plumosum and Plagiomnium venustum , on two malignant invasive plants, Echinochloa crusgalli and Daucus carota . The effects of mosses on seed germination and seedling growth of both invasive species were determined based on the clump structure and allelopathy of the mosses. The germination rate, germination potential and germination index of the two invasive species were significantly inhibited when seeds fallen on or into the moss clump, with an order of inhibition effect: above moss clump>below moss clump>no moss. Radicle length and radicle/plumule of D. Carota were significantly affected when seeds fallen into the moss clump. Moss water extracts significantly reduced germination rate, germination potential, and germination index of the two invasive plants, with these effects being concentration-dependent. To some extent, moss water extracts increased the plumule length, radicle length and radicle/plumule of D. Carota seedlings, but without effect on E. crusgalli . Both mosses showed inhibitory effects on seed germination and seedling growth of two invasive plants, with higher sensitivity of E. crusgalli than D. Carota . Along with the increases in concentration of water extract, stronger inhibitory effects were found. Therefore, mosses could partially inhibit seed germination and seedling growth of invasive plants.

The therapeutic effect of sustained intravitreal injectable voriconazole microspheres (VCZ-MS) on an experimental endophthalmitis of Aspergillus fumigatus was investigated. VCZ-MS was prepared successfully and its physico-chemical property was also evaluated. Right eyes of albino rabbits were infected with an intravitreal injection of 1 000 CFU x mL(-1) of susceptible Aspergillus fumigatus. All fungal endophthalmitis models were randomly divided into five groups 48 hours later: Group A is control group with no treatment; in group B, vitrectomy was performed combined with intravitreal 3 times injections of 100 microg x 0.1 mL(-1) voriconazole every other day. In group C, D and E, vitrectomy was performed combined with intravitreal injection of 0.5 mg, 1.0 mg and 1.5 mg VCZ-MS respectively. The treatment effect was assessed by slit lamp and indirect ophthalmoscope funduscopy examination, using clinical grading system of inflammation in the anterior chamber and the vitreous opacity. The optical microscopy revealed that microspheres obtained from the experiment design were opaque, discrete and spherical particles with smooth surfaces. The drug content and encapsulation efficiency of microspheres were 29.94% and 73.5%, respectively. Endophthalmitis occurred in all eyes of group A, and rapidly developed to panophthalmitis. The inflammation grade of group B, C, D or E was lower than that of group A (P < 0.05). The grade of vitreous opacity in group C, D, E is lower than group B (P < 0.05). Two eyes in group C developed to panophthalmitis. But in group D and E, all eyes whose inflammation was controlled had no recurrence with vitreous clear. Histopathological examination showed normal structures in the cured eyes, while most uncured eyes were atrophic and with eyeball destroyed. So, it can be safely concluded that the curative effect of intravitreal VCZ-MS is significantly better than that of routine intraocular injection of voriconazole. The optimal dose is the one containing 1.0 mg voriconazole.