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, teacher, historian and man of Wessex. New Scientist. 26 th May 1959, 1190-1191. [3] Brock WH. J.R. Partington (1886-1965): physical chemistry in deed and word. Bull Hist Chem. 2009;34(1):11-20. [4] Butler FHC. Obituary: James Riddick Partington (1886-1965). British J History Sci. 1966 June;3(1):70-72. [5] Hirst EL. John Read. 1884-1963, biographical memoirs fellows of the Royal Society. 1963;(9):236-260. [6] Smeaton WA, revised by Brock W. Partington, James Riddick (1886-1965). Oxford Dictionary of National Biography. 2011.

Abstract

The aquatic ecosystem of the Meskiana Valley (wilaya of Oum El Bouaghi) covers a large area with a permanent flow and a semi-arid climate characterized by a strong evapotranspiration. In order to determine the Physico-chemical quality, pollution and salinity of the water of the river of Meskiana and more particularly in its downstream part which is exposed to wastewater discharges, analyses were carried out at the level of three sampling points: witness, the upstream (before spill), downstream (after spill)). In order to prevent the risk of alkalization and salinization of soil, the sodium absorption rate (SAR) and the percentage of sodium were determined and represented on the Wilcox and Riverside diagram. The high concentrations of polluting chemical elements and excessive salinity obtained at the downstream site show a high risk of pollution and salinization.

Abstract

The volumes of reactions in solution are usually ignored in problem solving. Neglection of reaction volumes may lead to errors on the order of 1 % in the final result. Calculation of the volume of neutralization reaction based on the specific densities of solutions from chemical tables is demonstrated.

Abstract

In this study we evaluated new mixing (θ and ψ) Pitzer parameters, and developed models for solution behavior and solid liquid equilibria for the following mixed systems: 1) KCl-AlCl3-H2O, 2) KCl-FeCl3-H2O, 3) KCl-CrCl3-H2O, 4) MgCl2-AlCl3-H2O, 5) MgCl2-FeCl3-H2O, 6) MgCl2-CrCl3-H2O, 7) CaCl2-AlCl3-H2O, 8) CaCl2-FeCl3-H2O, and 9) CaCl2-CrCl3-H2O at 25°C. The solubility modeling approach, implemented to the Pitzer specific interaction equations is employed. The values of the binary parameters for the binary sub-systems needed here to parameterize models for mixed systems are taken from our previous studies. Mixing solution parameters are evaluated in this study using activity (when available) and solubility data. Following an approach in our previous modeling studies on M(III) chloride and sulfate systems, in this work we accept that complex Al(III), Cr(III), and Fe(III) aqueous species do not exist in solutions. We test the new models by comparing model predictions with experimental data (activity data for unsaturated solutions and solubility data in ternary systems). The agreement between model predictions and experimental data is very good. Combining present parameterization, with our M(III) models developed previously we fully complete our at 25°C model for the 8th component system Na-K-Mg-Ca-Al(III)-Cr(III)-Fe(III)-Cl-H2O. The resulting model calculates solubilities and solution activities to high solution concentration within experimental uncertainty. Limitations of the model due to data insufficiencies are discussed. The resulting parameterization was developed for the Pitzer formalism based PHREEQC database.

Abstract

Tycho Brahe, noted Danish astronomer and founder of modern astronomy died in Prague in 1691, at the age of 54, and was buried in the Church of the Virgin Mary before Týn. In 2010, at the request of Danish authorities, his remains were exhumed and an investigation into the cause of his death was undertaken, with an aim to addressing speculations of him having been poisoned. This report contains detailed information on the process of the exhumation and results of the subsequent investigation. An anthropological analysis confirmed the authenticity of the remains, that they are actually those of Tycho Brahe, and confirmed the results of an earlier exhumation, done in 1901. Physical chemistry analysis was unable to confirm a lethal or sub-lethal dose of heavy metal poison (Hg). A detailed paleopathological analysis of the skeleton confirmed that Brahe suffered from DISH (diffuse idiopathic skeletal hyperostosis), which attends Type II diabetes, high blood pressure and obesity (the metabolic syndrome). From period documents describing Tycho Brahe’s lifestyle and his last days, it seems likely that he died of complications resulting from these conditions, today described as diseases of affluence, also referred to as “Western disease”.

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References Aroca R (2006) Surface-Enhanced Vibrational Spectroscopy, John Wiley & Sons Inc. ISBN: 978-0-471-60731-1. BASF online. [accessible: 2016-1-26] http://www.standort-ludwigshafen.basf.de/group/corporate/siteludwigshafen/en/brand/2_PYRROLIDONE. Hartstein A, Kirtley JR, Tsang JC (1980) Physical Review Letters 45: 201-205. Kelly KL, Coronado E, Zhao LL, Schatz GC (2003) Journal of Physical Chemistry B 107: 668-677. Lal S, Link S, Halas NJ (2007), Nature Photonics 1: 641-648. Lee PC, Meisel D (1982) Adsorption and Surface- Enhanced Raman of Dyes on Silver and

References Ajitha MJ, Mohanlal S, Suresh CH, Jayalekshmy A (2012) Journal of Agricultural and Food Chemistry 60: 3693—3699. Álvarez-Diduk R, Ramírez-Silva MT, Galano A, Merkoçi, A (2013) The Journal of Physical Chemistry B 117: 12347—12359. Amić D, Stepanić V, Lučić B, Marković Z, Dimitrić Marković JM (2013) Journal of Molecular Modeling 19: 2593—2603. Becke A (1993) The Journal of Chemical Physics 98: 5648—5652. Binkley JS, Pople JA, Hehre WJ (1980) Journal of the American Chemical Society 102: 939—947. Bors W, Heller W, Michel C, Saran M (1990) Methods in

" University. In November 1973 she received her Ph. D. degree and then passed through all academic steps as follows: 1961-1972 assistant professor; 1972- 1983 lecturer; 1983-1992 associate professor and between 1992-2005 professor. After her retirement in 2005 she continued her research work as scientific advisor at the same department. 58 C. Moldoveanu Throughout her teaching activity, she taught courses in physical chemistry such as: Physical Chemistry, Chemical Kinetics and Catalysis, Chemical thermodynamics, Colloid