BACKGROUND Plating and pickling processes are the most effective ways for increasing the strength of metal structures, and workers in these units are exposed to various contaminants, including acid mists. The aim of this study was to investigate the effect of protective masks in decreasing the respiratory symptoms and the aerobic capacity of workers that are exposed sulfuric acid mist. METHOD...

A LTHOUGH MANY METHODS have been published for the determination of pregnanediol in urine, we found none of them fully satisfactory. The first gravimetric method (1), and colorimetric methods derived from this one (2, 3), are rather unspecific, because, especially under pathologic conditions, fairly large amounts of similar compounds are found in the so-called pregnanediol fraction. Determinati...

New modified acidic catalysts were prepared from the treatment of silica, titania and silica prepared from hydrolyzed tetraethyl orthosilicate (TEOS) with sulfuric and phosphoric acid. The sulfated and phosphated silica synthesized from TEOS were calcined at 450 and 650 ◦C. These catalysts were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmissio...

Technologies to collect and reuse sulfuric acid waste is attracting attention to reduce industrial waste in semiconductor manufacturing plants. Reusing sulfuric acid has a high economic value. By using sulfuric acid recycling equipment based on an atmospheric distillation method, we evaluated the recovery percentage of sulfuric acid, the concentration and quality of recycled sulfuric acid, and ...

Sulfuric acid is a common chemical that is widely used in industry and is found in consumer products (e.g., car batteries, cleaning products). In the United States sulfuric acid is ranked number one in terms of production volume. Sulfur trioxide is a precursor to the production of sulfuric acid. Oleum (fuming sulfuric acid) is sulfur trioxide absorbed in concentrated sulfuric acid. Sulfur triox...

Concrete is the most widely used material for the construction of the wastewater collection, storage, and treatment infrastructure. The chemical and physical characteristics of hydrated Portland cement may make it susceptible to degradation under highly acidic conditions. As a result, some concrete wastewater infrastructure may be susceptible to a multistage degradation process known as microbi...

in cases of overdose and identification of the actual barbiturate concerned may be impossible because of the closely similar Rf values of this group. Jackson (1960) described treatment with hot sulphuric acid before paper chromatography to distinguish between barbiturates of similar chromatographic mobility. The inert nature of the silica gel supporting medium used in thin-layer separations ena...

0019-1035/$ see front matter Published by Elsevier doi:10.1016/j.icarus.2011.06.008 ⇑ Corresponding author. Fax: +1 301 286 0440. E-mail address: [email protected] (M.J. Loeffl We report laboratory studies on the 0.8 MeV proton irradiation of ices composed of sulfuric acid (H2SO4), sulfuric acid monohydrate (H2SO4 H2O), and sulfuric acid tetrahydrate (H2SO4 4H2O) between 10 and 180 K. Usin...

This work proposes an environmentally safe and economically feasible method of waste copper-nickel production slag utilization (Kola Mining-Metallurgical Company, Nornickel, Kola Peninsula, Russia). process involves the decomposition by diluted solutions sulfuric acid (7–10 wt.% H2SO4) with a transfer in solution more than 70% silicon, 77% iron 78% magnesium, concentration non-ferrous metals re...