Browsing by Subject "Substitution reactions"

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    Use of zeolite, coal bottom ash and fly ash as replacement materials in cement production
    (2004) Canpolat F.; Yilmaz K.; Köse M.M.; Sümer M.; Yurdusev M.A.
    In this research, the effects of zeolite, coal bottom ash and fly ash as Portland cement replacement materials on the properties of cement are investigated through three different combinations of tests. These materials are substituted for Portland cement in different proportions, and physical properties such as setting time, volume expansion, compressive strength and water consistency of the mortar are determined. Then, these physical properties are compared with those of PC 42.5. The results showed that replacement materials have some effects on the mechanical properties of the cement. The inclusion of zeolite up to the level of 15% resulted in an increase in compressive strength at early ages, but resulted in a decrease in compressive strength when used in combination with fly ash. Also, setting time was decreased when zeolite was substituted. The results obtained were compared with Turkish Standards (TS), and it was found that they are above the minimum requirements. © 2004 Published by Elsevier Ltd.
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    Evaluation of Phytic Acid Content of Some Tea and Nut Products by Reverse-Phase High Performance Liquid Chromatography/Visible Detector
    (Springer New York LLC, 2016) Dost K.; Karaca G.
    Phytic acid contents of nine different types of nut and six different types of tea and steeped tea were analysed by reverse-phase high performance liquid chromatography with visible detector. The extraction method was based on hydrochloric acid extraction, and the analysis method was based on metal replacement reaction of phytic acid from coloured complex (iron(III)-thiocyanate), separation on CN column and monitoring the absorbance at 460 nm. The retention time for the monitored iron(III)-thiocyanate peak was achieved less than 3 min. The proposed HPLC/Vis procedure shows good linearity over the concentration range of 1–150 mg L−1 with a correlation coefficient value of 0.9938. The effectiveness of metal replacement reaction was presented in terms of relative standard deviation that was 0.62 and 0.88 % for 5 and 50 mg L−1 of phytic acid, respectively. Repeatability of the analytical method was ranging between 1.58–7.88 % (n = 10, for 50 mg L−1) and 0.98–4.63 % (n = 10, for 5 mg L−1) in terms of relative standard deviation. Accuracy of the method is good, ranging relative error between 4.52 and 8.00 % (n = 10, for 50 mg L−1). Phytic acid content is in the range of 1.54 to 9.74 mg g−1 in nuts, 27.67 to 28.82 mg g−1 in green teas, and 20.49 to 21.96 mg g−1 in pocketed roasted teas. © 2015, Springer Science+Business Media New York.