Sulfuric acid dynamic effect

Spectrophotometry shows that heterocyclic analogs of chalcones101 when protonated by 100% sulfuric acid dissolved in acetic acid form hydrogen bonds and reveals a positive dynamic conjugation (electromeric) effect which decreases in the series a-furyl > a-selenienyl > a-thienyl. 

It is therefore mainly limited to the cocondensation of sulfuric acid and water. The acid in this case is produced in the atmosphere by gas phase oxidation of SO2. A special case is the production of sea salt aerosols over the oceans, which are effectively produced by the disintegration of air bubbles on the ocean. The atmospheric aerosol is a dynamic system the initially produced particles undergo various processes like heterogeneous condensation, coagulation, and deposition which lead to a change in their size and chemical composition and gives rise to the universality of the aerosol size-distribution. 

Fig. 4.11 Sulfuric acid experimental washing (dynamic effect)...

I- H2O has been investigated by spectroscopic [37, 41,42] and theoretical [38, 43, 44] methods. Dynamical simulations of the dehydration reaction find two mechanisms to be operative in this reaction a fast loss of H2O initiated by hydrogen atom hopping, similar to that found following nitric acid excitation, and a slower dissociation, occurring after full or partial IVR [43,45]. Based on these mechanisms and rates, the dehydration of sulfuric acid is very effective under conditions of the upper stratosphere and mesosphere [46]. The rate of dehydration thus obtained is... 

The effects of solvent exposure on the viscoelastic properties of several vinyl ester resins (phenohc-novolac epoxy, propoxylated bisphenol-A fu-marate, urethane and bisphenol-A epoxy based) and various unsaturated polyester resins (terephthalic or isophthaUc acid with a standard glycol based) containing 10wt% glass fiber were studied [130]. The results of dynamic mechanical analysis showed that the influence of exposure time to the solvent as well as the influence of temperature depended on the styrene content and chemical composition of the studied resins, while the amount of cobalt octoate used for the synthesis as the accelerator had no influence on the viscoelastic properties of the prepared materials after solvent exposure. It was also found that not fully cured urethane vinyl ester and the terephthahc acid-based unsaturated polyester resins showed excellent resistance to sulfuric acid exposure. However, interactions between the tested resins and petroleum could possibly occur through intermolecular bonding between the non-polar chains of the cured resins and the solvent. 

Most microbial desulfurization studies have been conducted in the laboratory shake-flask type experiments, and the major drawback cited against such a process has been that the rates of pyritic sulfur removal were not high enough to reduce the reactor size to a reasonable capacity (2,6). In this study an attempt has been made to determine the effectiveness of T. ferrooxidans under simulated pipeline conditions for pyritic sulfur removal. Since the microbial desulfurization process is conducted under acidic environment, an attempt has been made to determine the corrosion rates under dynamic conditions using Illinois //6 and Indiana 3 bituminous coals and to investigate the effectiveness of a commercial corrosion inhibitor for controlling the corrosivity. 

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