We have performed a series of simulations with an aerosol dynamics box model to study the connection between new particle formation and sulphuric acid concentration. For nucleation either activation mechanism with a linear dependence on the sulphuric acid concentration, kinetic mechanism with a squared dependence on the sulphuric acid concentration or ternary H2O-H2SO4-NH3 nucleation was assume...

Sulphuric acid is a key component in atmospheric new particle formation. However, sulphuric acid alone does not form stable enough clusters to initiate particle formation in atmospheric conditions. Strong bases, such as amines, have been suggested to stabilize sulphuric acid clusters and thus participate in particle formation. We modelled the formation rate of clusters with two sulphuric acid a...

sulphuric acid adsorbed on silica gel is a practical and useful catalyst for acetylation of varius alcohols, phenols and amines.

In atmospheric conditions the oxidation of sulphur dioxide to sulphuric acid in gas phase has been considered to be determined by the concentration of hydroxyl radical. Recently the significance of stabilized Criegee intermediate as an oxidizer of sulphuric acid has been brought out. In this study we investigated the oxidation of sulphur dioxide in the CLOUD chamber in conditions where the hydr...

Three mixtures were used for wet digestions: nitric and sulphuric acids, 30 per cent. hydrogen peroxide and sulphuric acid, and selenium and sulphuric acid. In the nitric acid digestion 3 ml. of conceintrated sulphuric acid was used for each gram of dry plant material, a total of 50 inl. of concentrated nitric acid was added in four portions, the mixture being evaporated to white fumes and cool...

From the standpoint of processing, hard chromium layer plate may be applied to steels, cast iron, aluminum and nickel base alloys. Cast iron can be plated provided that the surface is capable of conducting the required current and is reasonably free of voids, pits, gross silicate inclusions, and massive segregation. There are many difficulties arising from graphite phase and deposition of hydro...

We have investigated the formation and early growth of atmospheric secondary aerosol particles building on atmospheric measurements. The measurements were part of the QUEST 2 campaign which took place in spring 2003 in Hyytiälä (Finland). During the campaign numerous aerosol particle formation events occurred of which 15 were accompanied by gaseous sulphuric acid measurements. Our detailed anal...

Nitration of potassium sulphamate was carried out using a mixture of sulphuric and nitric acid at -30 °C. The reaction time was optimized at the mole ratio of sulphuric to nitric acid of (1:3.5). The difference in product yield by changing the potassium to ammonium sulphamate was studied throughly. It was found that both the yield and purity of the product is better starting with potassium ...

a simple extremely fast and efficient approach for the synthesis of substituted indazole ingood to excellent yield catalyzed by using silica sulfuric acid (ssa) in dmso solvent at roomtemperature. this is solid state reaction have been attracting the synthetic organic chemist asthey provided enhance reaction rates, less environmental pollution, greater selectivity, cleanerproducts and manipulat...