Introduction: North West Africa (NWA) 852 and 801 are classified as CR2 chondrites [1-2]. The two meteorites contain relatively large chondrules (1-2 mm in diameter), FeNi metal, and dark inclusions composed of serpentine and olivine. We measured noble gases in the two meteorites with stepwise heating, which facilitates decomposition of noble gas components with different origins and trapping s...

statement of problem: the effect of porcelain surface on the antagonist acrylic teeth has not been widely studied. objectives: this study aimed to investigate the effect of polished porcelain, glazed porcelain, and natural teeth (as the control group) on the acrylic resin teeth. materials and methods: in this experimental-laboratory study, a total of 60 specimens of glazed and polished porcelai...

A flatbed scanner is used to collect a digital image of a polished cross-section through a concrete pavement. Image processing software is used to classify each pixel in the image as either cement paste, aggregate, or air void. The distance to the nearest air void is calculated for each pixel classified as cement paste using an accumulated cost surface algorithm. The presence of aggregate is ac...

The recognition of grain boundaries in deformed rocks from images of thin-sections or polished slabs is an essential step in describing and quantifying various features and analysis, which is usually achieved by image processing procedures. Recently, researchers from geoscience and computer science focused on this issue and many methods have been proposed. We begin with an application of minera...

The purpose of tins study was to evaluate the surface produced when stainless steel crowns were polished by several technics and to compare the ability of the various polished surfaces to resist bacterial plaque accumulation. Twenty-one Unitek and twenty-one Ion primary molar stainless steel crowns were divided into several groups containing three crowns each. Each group was polished with a dif...