A natural bentonite obtained from Khorasan, Iran, was submitted to acid activation with sulphuric acid. Sample aliquots (5gr)were leached with 100 ml H2SO4 solutions of various concentrations (2–7N) at 80±2 oC for 2 hours. X–ray diffraction, chemical analysis, infrared spectroscopy and specific surface area measurements were performed in order to evaluate important structural modifications occ...

Menthol vapours are irritant to eyes, nose and throat, and ingestion of this chemical has been reported by Von Oetingen (1958)1) to cause abdominal pain, vomiting, staggering gait and sopor. The workers exposed to high concentrations of menthol vapours in an industry manufacturing menthol crystalls from the plant extracted mentha oil complained of drowsiness, headache, nausea and vomiting. Till...

Sulphuric acid vapour has been suspected of being an industrial carcinogen. In this study, a cluster is presented of three patients with nasopharyngeal carcinoma (NPC) who worked in the same building of a telecommunications conveyance station in southern Taiwan with long term exposure to sulphuric acid vapour concentrations as high as 0.18 mg/m3. All three workers were diagnosed with NPC within...

In order to gain a more comprehensive picture on different mechanisms behind atmospheric particle formation, measurement results from QUEST 2-campaign are analyzed with an aid of an aerosol dynamic model. A special emphasis is laid on air ion and charged aerosol dynamics. Model simulations indicate that kinetic nucleation of ammonia and sulphuric acid together with condensation of sulphuric aci...

An account is given of some recent developments in the chemistry of solutions in highly associated strong protonic acid solvents, including sulphuric acid and oleums, fluorosuiphuric acid and hydrogen fluoride. Topics discussed include solvent—solute interactions, super-acid systems, Hammett acidity functions and polyatomic cations of the elements of Groups VI and VII.