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Advanced High Voltage Cathode Materials for Rechargeable Lithium Ion Batteries
Published in Thandavarayan Maiyalagan, Perumal Elumalai, Rechargeable Lithium-ion Batteries: Trends and Progress in Electric Vehicles, 2020
J. Richards Joshua, T. Maiyalagan, N. Sivakumar, Y.S. Lee
Metal fluorides are mainly used for research because of high stability and ability to produce ions suitable for efficient charge transfer between electrodes producing high operating voltages and reversible capacities [127]. Iron Fluoride FeF3 , is cost effective and is characterized by high theoretical capacity of about 712 mAh/g. In 1990, Aria et al. first reported the electrochemical properties of trifluorides with specific capacity of about 80 mAh/g [128]. Figure 6a shows the reactions take place in FeF2 particles.
Regression Analysis
Published in Robert M. Bethea, R. Russell Rhinehart, Applied Engineering Statistics, 2019
Robert M. Bethea, R. Russell Rhinehart
Example 8.1 In areas where excess iron fluoride occurs naturally in water, the local water department must constantly monitor the water for fluoride concentration. Because of interferences by other ions, your local public health department has decided to evaluate a new colorimetric method for the analysis of fluoride in aqueous solution. After standardizing the colorimeter against a sample of the reagent that contained no fluoride, the following calibration data were obtained for two independent trials at each of 10 concentrations. The calibration equation and plot will be used to determine the fluoride (F−) concentration when transmittance (%T) is measured. Although the data were generated with concentration as the manipulated (independent) variable, our results will use %T as if it were the independent variable.
Multi-criteria Evaluation of Hydrogeological and Anthropogenic Parameters
Published in Prashant Kumar, Praveen K. Thakur, Sanjit K. Debnath, Groundwater Vulnerability Assessment and Mapping Using DRASTIC Model, 2019
Prashant Kumar, Praveen K. Thakur, Sanjit K. Debnath
Validation of such kind of empirical studies is difficult in the sense that vulnerability maps generated by these empirical models, which take into account the physical parameters, can’t be always very accurate due to the complex dynamics of groundwater. This can never replace the cumbersome manual on-site physical investigations for ground truth. But, DRASTIC, being a rapid regional assessment technique, can always give approximate vulnerability maps which can further be used for area-wise in-depth analysis. In order to validate the results, ten water quality parameters (Kalinski et al. 1994; Mogaji et al. 2014), viz., total alkalinity, pH, TDS, hardness, magnesium, sulphate, calcium, iron, fluoride, and nitrate have been used, available with us for 241 sample points spread uniformly across the study area.
Effect of nitric acid contamination on mild steel corrosion in hydrofluoric acid at 25°C
Published in Corrosion Engineering, Science and Technology, 2020
R. van der Merwe, J. W. van der Merwe, L. A. Cornish
Different colours observed in the scale layers were associated with different corrosion reactions (by oxidation (HNO3) or reduction (HF)) on the coupons’ surfaces in the corrosion solutions used. The dark grey surface with mottled light brown scale was a recognisable feature of the pre-passivated mild steel coupons (Figure 1: Row (b)), which were first identified in the planned interval corrosion tests (PICTs) [4]. According to Haynes [22], iron fluoride, FeF2, is grey, while the ferric hydroxide, FeF3·3H2O, is distinctly yellow-brown. The scale in this work was identified as a mixture of iron (II/III) oxides (black), iron fluoride (grey) and ferric hydroxide (light yellow-brown) from X-ray diffraction conducted on the failed tanks (since the coupons were too small and rough to give a good signal [11,24]).
Use of zinc oxide nanoparticles for detection of fluoride in toothpaste gel
Published in Journal of Environmental Science and Health, Part A, 2022
Wasupon Watjanavarreerat, Liviu Steier, Kitsakorn Locharoenrat
Fluoride ions react with iron ions to produce an iron–fluoride complex with a probable formula of [FeFn]3−n. Because of the metal-to-ligand charge transfer and/or ligand-to-metal charge transfer, the characteristic intense colors are observed, which allows the increase in the absorption intensity of the iron–fluoride complexes with the ferrozine chelators in the visible region.[13,14] The binding interactions of the solvent molecules with the iron–fluoride complex are altered in the presence of solvents such as acetone, chloroform, and toluene.[25]