Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

Browse

Filters

2010 - 201912020 - 20231

Settings

Department: search.filters.department.Izmir Institute of TechnologySubject: search.filters.subject.Precipitation

Search Results

Now showing 1 - 2 of 2
  • Book Part
    Control of the Particle Size and Purity of Nano Zinc Oxide
    (Nova Science Publishers, Inc., 2010) Omurlu,F.O.; Balköse,D.
    Effects of template, mechanical mixing and/or ultrasound mixing on the size of the ZnO crystals obtained by precipitation at 30 °C from aqueous zinc chloride and potassium hydroxide solutions were investigated by 2k factorial design. Precipitation method is employed to synthesize nano zinc oxide particles. Monodisperse nano ZnO having 29 nm particle size was produced by adding triethyl amine and applying simultaneously mechanical and ultrasound mixing. The surface area and the density of the powder were 21 m2/g and 4.8 g/cm3. It contains 5.2% impurities present as CO3 -2 and bound OH- groups. Volumetric resistivity was found as 1.3 × 107ohm cm. Absorption spectrum of the powder showed absorption peak at 353 nm. The room temperature fluorescence spectrum of the powder revealed a strong and sharp UV emission band at 391 nm due to free exciton or bound exciton of ZnO and a weak and broad violet emission band at 405 nm due to zinc vacancies. © 2014 by Nova Science Publishers, Inc. All rights reserved.
  • Article
    Citation - Scopus: 3
    A Brief Overview on Geothermal Scaling
    (General Directorate of Mineral Research and Exploration (MTA), 2023) Isık, Tuğba; Baba, Alper; Chandrasekharam, Dornadula; Demir, Mustafa M.; Isık, Tuğba; Baba, Alper; Demir, Mustafa Muammer
    Hot spring waters are rich in terms of minerals. Since there are dramatic changes in thermodynamic parameters in geothermal power plants, such as a decrease in temperature and pressure, severe precipitation occurs throughout the system components in an uncontrolled manner. There are three main chemistries in deposits: carbonates (mainly calcium carbonates), silicates (metal silicates), and sulphides (antimony sulphide-stibnite). Energy harvesting is remarkably reduced out of the insulating nature of the deposit. Various actions need to be taken to mitigate this undesirable issue of scaling in geothermal systems. Geothermal systems are in fact quite complex, and the composition of brine and, accordingly, the chemistry of the deposit are not identical. Therefore, each system should be studied individually, and a tailor-made remedy should be developed. In this overview, the types of deposits in terms of chemistry and the actions (pH modification or antiscalant dosing) that should be taken to reduce scaling are mentioned, and potential chemistries of antiscalants are given.