NOPR Collection:

Svante Arrhenius and the Greenhouse Effect

2002-03-01T00:00:00Z

Title: Svante Arrhenius and the Greenhouse Effect Authors: Wisniak, Jaime Abstract: Svante Arrhenius (1859-1927; 1903 Nobel Prize in Chemistry) is one of the most famous scientists of the last century. His theories about electrolyte dissociation, chemical kinetics, physical chemistry, and immunochemistry set the direction for the development of modern electrochemistry, theory of solutions, and catalytic processes. Very few are aware of hi s substantial contribution to the stud y of the effect of atmospheric contamination upon climate and the possible reasons of the different Ice Ages that the Earth has experienced during different historical epochs. Here a general description of the so-called greenhouse effect and Arrhenius's contribution to its interpretation is being presented. Page(s): 165-173

Nitrogen dioxide formation at ambient temperature

2002-03-01T00:00:00Z

Title: Nitrogen dioxide formation at ambient temperature Authors: Verma, S S Abstract: The explanation of the formation and existence of nitrogen dioxide (NO₂) at ambient temperature is important towards the basic understanding of the nature of chemical reactions of the pollutants in the atmosphere and to the visibility of the atmosphere. The objectives of the present studies are to highlight the detailed effect of ambient temperature on the conversion of nitric oxide (NO) to NO₂ in the presence of ozone (O₃) gas with varying concentrations of other species viz. , N₂, CO₂, CO, H₂O, O₂, etc. It is found that O₃ is the only chemical species active up to its last concentration involved in the conversion of NO into NO₂ at ambient temperature. Page(s): 159-164

Non-promoted Ru/sepiolite catalyst for ammonia synthesis

2002-03-01T00:00:00Z

Title: Non-promoted Ru/sepiolite catalyst for ammonia synthesis Authors: Zhiping, Le; Xiujing, Yu; Jianxin, Lin; Kemei, Wei Abstract: Sepiolite was used as support for ruthenium catalyst. Non-promoted Ru/Sep is proved to be effective for ammonia synthesis. The catalyst was characterized by XRD, XPS and nitrogen adsorption isotherms. Ru is reduced completely and is present in few oxidation states on the support. Using non-aqueous solvent instead of water in the impregnation process on basic support, the Ru dispersion could be increased. Chlorine-free Ruthenium catalyst was prepared using RuCl₃ by washing with ammonia solution. Page(s): 154-158

Corrocal—A computer program for corrosion current density determinations from polarisation experiments

2002-03-01T00:00:00Z

Title: Corrocal—A computer program for corrosion current density determinations from polarisation experiments Authors: Siva, R Rengesh; Prabhakar, R; Muralidharan, V S Abstract: One area in which computers find use is in the calculation of Corrosion current density and rate calculations. To calculate electrochemical parameters such as anodic and cathodic Tafel slopes, corrosion current density and polarisation resistance, a software has been developed using C++ language. The software would process data obtained either from a galvanostatic experiment or potentiostatic experiment. The potentials are given in milli volts and the current as microamperes as input. The developed software would find : a) Corrosion currents by anodic and cathodic Tafel line extrapolations, b) corrosion rates expressed as mpy, c) Cathodic and Anodic Tafel Slopes, d) Corrosion currents by Stern - Geary method, e) Corrosion currents by Barnatt's method, f) Corrosion currents by Oldham and Mansfeld's method. Details of the Corrocal and its applications to various systems are presented. Page(s): 148-153