Search results for "Mean diameter"
showing 4 items of 4 documents
Thermally Induced Structural Modification of Silica Nanoparticles Investigated by Raman and Infrared Absorption Spectroscopies
2010
We report an experimental investigation by Raman and infrared (IR) absorption spectroscopies on the structural modifications induced by isochronal thermal treatments on amorphous SiO2 nanoparticles (fumed silica). In particular, three different commercial types of this material, characterized by particle mean diameters of 7, 14, and 40 nm, were subjected to thermal treatments from 100 up to 1000 °C. We found that some properties of fumed silica, such as the SiOSi mean bond angle, ring size distribution, and surface adsorbed water content, are drastically different from those of common bulk silica materials and intimately related to the particles' dimension. The SiOSi mean bond angle, probed…
Determination of biological characteristics of Tunisian Artemia salina populations
2012
In this study, Artemia salina cysts collected from four Tunisian hypersaline environments were characterized using biometrical, biological and biochemical descriptors. Biometrical analysis revealed that the mean diameter value ranged from 220.25 to 237.76 μm, for the untreated cysts, from 199 to 224.52 μm for decapsulated cysts and that the chorion thickness ranged from 6.62 to 10.58 μm. 48 h after hatching, Artemia from Sebkha El Meleh, Sebha Moknine, Sfax saltworks and Sahline saltworks presented a hatching percentage of 52.7%, 53.75%, 70.16% and 43.74%, respectively. The length of the freshly hatched instar I nauplii varied from 429 to 449.34 μm. The fatty acids profile showed that the n…
Study on Interfacial Surface in Modified Spray Tower
2019
This paper presents an analysis of the changes in interfacial surface and the size of droplets formed in a spray tower. The interfacial surface and the size of droplets formed are of fundamental importance to the performance of the equipment, both in terms of pressure drop and process efficiency. Liquid film and droplet sizes were measured using a microphotography technique. The confusors studied were classical, with profiled inside surface, and with double profiled inside surface. The liquids studied were water and aqueous solutions of high-molecular polyacrylamide (PAA) of power-law characteristics. The ranges of process Reynolds number studied were as follows: ReG &isin
Decreased dentin tubules density and reduced thickness of peritubular dentin in hyperbilirubinemia-related green teeth.
2016
BACKGROUND It is stated anecdotally that patients with liver diseases in childhood who develop green teeth have increased risk for rampant caries, which may be secondary to changes in dental structure. The aim of this study was to test the hypothesis that hyperbilirubinemia affects the dentin morphology of green teeth. MATERIAL AND METHODS Sixteen primary teeth were prepared and divided into two groups (green teeth, n = 8 and control, n = 8), which were transversely fractured across the cervical third of the dental crowns; dentin was prepared and sputter-coated with gold, and examined under a scanning electron microscope. The mean density and mean diameter of dentin tubules, as well as the …