Automatic damage detection of engineering ceramics ground surface based on texture analysis

Ground textures seriously interfere with the exact identification of grinding damage. The common nondestructive testing techniques for engineering ceramics are limited by their difficulty and cost. Therefore, this paper proposes a global image reconstruction scheme in ground texture surface using Fourier transform (FT). The lines associated with high-energy frequency components in the spectrum that represent ground texture information can be detected by Hough transform (HT), and the corresponding high-energy frequency components are set to zero. Then the spectrum image is back-transformed into the spatial domain image with inverse Fourier transform (IFT). In the reconstructed image, the main ground texture information has been removed, whereas the surface defects information is preserved. Finally, Canny edge detection is used to extract damage image in the reconstructed image. The experimental results of damage detection for the ground texture surfaces of engineering ceramics have shown that the proposed method is effective.     

近代枫溪潮州窑与大窑五彩瓷的创烧

该文通过文献、实物、口述历史等资料,就近代枫溪大窑五彩瓷创烧的历史背景、工艺特色、外销等方面进行探讨,指出：“枫溪大窑五彩”的创烧,有着重要的历史意义,不仅在工艺上具有创新性、时代性,而且体现枫溪潮州窑在近代“世界性窑业”中的影响。     

热等静压制备Nd:YAG陶瓷及其微观结构与光学性质(英文)

采用共沉淀法制备Nd:YAG前躯体,将该前躯体1100℃煅烧2小时得到纯相Nd:YAG粉体;该粉体经1800℃真空烧结10小时得到Nd:YAG透明陶瓷.由SEM结果可知,陶瓷表面存在气孔及晶界相,样品平均粒径约为8μm.陶瓷经热等静压1650℃(2小时)处理后,表面气孔、缺陷及晶界相明显减少,且陶瓷更加致密,晶粒大小无明显变化.虽然经热等静压处理的样品仍有少量晶内气孔,但在可见光区,最大透过率达到50%.     

玻璃模具材料及其发展

总结了玻璃模具材料的应用现状与发展趋势,结合玻璃模具的使用特点和性能要求,提出复合材料可以综合两种材料的优势,提高模具材料的使用性能,在玻璃模具中具有良好的发展前景．     

Structural and dielectric properties of Y2O3-doped Ba0.92Sr0.08Ti0.95Sn0.05O3 ceramics

The structural and dielectric properties of Ba0.92Sr0.08Ti0.95Sn0.05O3 (BSTS) +x (molar ratio, %) Y3+ ceramics are investigated. Combining the lattice parameters and the distortion of crystal lattice, an alternation of substitution preference of Y3+ ion for the host cations in perovskite lattice is found. Owing to Y3+ ion entering the A site, the maximum dielectric constant is 5 627 for 1.25% Y3+-doped samples; when Y3+ ion is more than 1.25%, it tends to occupy the B site in perovskite lattice, causing a drop in the dielectric constant. Owing to the appearance of oxygen vacancy, the optimized dielectric loss is 0.004 for 1.25% Y3+-doped samples. The thermal stability of BSTS ceramics is significantly improved and the Curie temperature shifts to lower value with the amount of Y2O3 increased, making it a superior candidate for capacitor applications.     

基于后混合式磨料水射流切割机理的探讨

阐述了磨料射流的构成以及磨料射流的混合机理、理想的磨料水射流混合过程和实际的混合过程、切割动能理论.讨论了切割工艺参数、磨料参数、物料的性能参数对切割深度的影响.     

… I ever loved thee,lady mine,and yet my love increases: Rhodian Portrait Ceramics and Cultural Dialogue in the Mediterranean

The medieval city of Rhodes kept a secure position as artistic and commercial crossroads, where pottery was the most intensely traded commodity. Here, I focus on a group of fifteenth-century ceramics decorated with profile busts of men and women excavated there, near the Orthodox Church of St. Spyridon. Used in a culturally complex urban centre, these vessels borrowed elements of design, and the concept of portrait-ceramics and love pots from Italy, where spouses and lovers exchanged such objects as ritual gifts. I explore the patronage, production, and function of these ceramics within the specifics of Rhodes, to see how they were suited to serve this cosmopolitan society governed by the Hospitaller Knights of St. John of Jerusalem, while displaying comparable feelings of power and (romantic) character common in Italian portraiture.     

A note on glass and silica in oil paintings from the 15th to the 17th century

This articles reports new discoveries relating to ground glass and silica in European easel paintings from the 15th to the 17th centuries that were created by various German, Italian and Netherlandish artists. The earliest known additions of these extenders date to the early 1430s. Glass powder of varying fineness, prepared from vessel or window cullet, is often found in red lake glazes as well as in other colours or preparatory layers of paintings. SEM/EDX analyses of the glass particles reveal a variety of chemical compositions (soda ash, wood ash, wood ash-lime, wood ash-lead, mixed alkali), which are discussed with respect to the provenance of the paintings. Historical sources on painting techniques mention glass additions most frequently to accelerate drying of oil paints, but also occasionally to facilitate grinding of pigments. Another possible function of powdered glass and silica, especially in oil-bound red lake glazes, is that of a transparent filler, as will be here discussed based on paint trials.     

基于弹性大挠度理论的幕墙玻璃设计

根据弹性薄板大挠度理论,运用加权残值法分析计算幕墙玻璃的挠度和应力,并与幕墙玻璃规范设计进行比较,结果表明,基于非线性理论的设计计算是可行的.