Investigation of Direct Reduction Mechanism of Attepe Iron Ore by Hydrogen in a Fluidized Bed

In this study, the kinetics of reduction of Attepe iron ore by H-2 in a batch fluidized bed is analyzed at temperatures of 873 K, 973 K, and 1073 K (600 A degrees C, 700 A degrees C, and 800 A degrees C). It is determined that the reduction route includes two consecutive regions controlled by distinct steps. The first region which takes place at low reduction levels is determined to be controlled by nucleation of wustite, while the following is determined to be controlled by gas/solid reaction occurring at metallic iron/wustite interface. An "ad-hoc" model is used to represent the reduction of Attepe iron ore to metallic iron with good accuracy

Determination of reduction degree of direct reduced iron via FT-IR spectroscopy

In this study, the applicability of FT-IR spectroscopy to determination of direct reduction degree of Attepe iron ore was examined. For that purpose, infrared spectra of all samples generated as the stack gas of the reduction reaction were recorded in a ZnSe windowed gas cell equipment at 2 cm(-1) resolution. Thus the variation of the stack gas composition with time was monitored. The degree of reduction for iron ores (R%), given as the ratio of removed oxygen amount during the reaction to the initial total oxygen content of ore, was estimated by both the FT-IR analysis of the stack gas and the volumetric analysis of the reduced iron ore samples. The results obtained by both gas and solid analyses were compared and a satisfactorily good agreement was observed. As a result, it is concluded that FT-IR Continuous Emission Monitoring (CEM) is a reliable, rapid and efficiently applicable analysis method for DR processes and for more other FT-IR traceable gas-solid reactions as well. (C) 2012 Elsevier B.V. All rights reserved

The effects of risperidone, olanzapine and haloperidol on enzyme activities in erythrocytes and plasma of rats

In this paper, we study the Lehmer's type congruences for lacunary harmonicsums

Effects of hippophae rhamnoides extract on oxidative mucosal injury induced by cisplatin in rat jejunum

Objectives: We aimed to assess the effect of Hippophae rhamnoides extract (HR) on oxidative stress induced by cisplatin (Cis) in rat small intestine tissue by evaluating the biochemical and gene expression levels and histopathological changes. Materials and methods: The control group and Cis group received distilled water, while the HR25+cisplatin (HR25+Cis) group and the HR50+cisplatin (HR50+Cis) group were given HR 25 and 50 mg/kg, respectively, orally for seven days. HR25+Cis, HR50+Cis, Cis groups were injected with a single dose of intraperitoneal cisplatin on the first day. After sacrifice, the jejunum of each rat was removed for the assessment of oxidants and antioxidants. Analyses of the gene expression (for IL-1ß and TNF-?) and histopathological changes evaluated. Results: HR significantly inhibited the increase of oxidants and the decrease of antioxidants caused by cisplatin in the jejunal tissue. IL-1? and TNF-? gene expression levels were almost the same in both the HR50+Cis and the control groups. HR better prevented increase of the serum levels of IL-1? and TNF-? in animals at 50 mg/kg dose compared to 25 mg/kg dose. We confirmed that HR prevented the histopathological changes caused by cisplatin. Conclusions: It was concluded that oxidative stress caused by cisplatin may be preventable by co-administered HR. © 2018, Scientific Publishers of India. All rights reserved