The average ionic strength of 20 West Australian soils was found to be 0·0048. The effects of three electrolytes (deionized water, CaCl2 and KN03), three ionic strengths (0'03. 0·005 and soil ionic strength at field capacity, Is) and two soil liquid ratios (1:5 and 1:10) on the pH of 15 soils were investigated. pH measurements in solutions of ionic strength 0·005 differed the least from measure...

Rate and activation parameters for the complex-formation reaction of Ni(2+) with 4-(2-pyridylazo)-N,N-dimethyl aniline (PADA) were studied as a function of pH in different buffers in both aqueous and sodium dodecyl sulfate (SDS) micelle solutions. In aqueous Tris buffer solution, the forward and backward rate constants increased with increasing pH, while the complex-formation constant decreased...

Since CO(2) is carbonic acid gas, it will decrease the pH if added to water. Therefore, a simple test can determine whether CO(2) is present in a gas mixture. If the pH of gassed water does not change significantly, then CO(2) is not present in the gas.

Raw surface and ground waters used for drinking purposes can vary markedly in their chemical and biological composition. Inorganic content (such as salt, bicarbonate, clay and metal ions), organic content (natural organic matter and anthropogenic compounds, including pollutants) and micro-organisms present in raw water are key drivers for treatment processes that provide for safe and aesthetica...

Diel pH changes in lake waters resulting from high photosynthetic activity may regulate water-soluble P concentration (WSP) and P sorption by suspended sediments in shallow eutrophic lakes. Laboratory studies were conducted to determine the pH effect on P fractions and P sorption kinetics in oxidized sediment suspensions from two subtropical lakes (Lake Apopka and Lake Okeechobee, Florida). The...

The wetlands of the Magela floodplain of northern Australia, which is the major sink for dissolved metals transported in the Magela Creek system, contain acid-sulfate sediments. The rewetting of oxidized acid-sulfate soil each wet season produces acidic pulses that have the potential to alter the bioavailability of sediment-associated metal contaminants. Acute toxicity tests (72-h mean lethal c...

The amino acid composition and the physicochemical and functional properties of quinoa protein isolates were evaluated. Protein isolates were prepared from quinoa seed by alkaline solubilization (at pH 9, called Q9, and at pH 11, called Q11) followed by isoelectric precipitation and spray drying. Q9 and Q11 had high levels of essential amino acids, with high levels of lysine. Both isolates show...

In this study, we report the assembly of amphiphilic polymeric micelles at the liquid/air interface to prepare liquid marbles for the first time. The polymeric micelles were synthesized from the self-assembly of a fluoropolymer, poly(styrene-co-acrylic acid-co-2,2,3,4,4,4-hexafluorobutyl methacrylate), in a selective solvent. The particle size, morphology and chemical composition of the micelle...

pH is a fundamental aerosol property that affects ambient particle concentration and composition, linking pH to all aerosol environmental impacts. Here, PM1 and PM2.5 pH are calculated based on data from measurements during the California Research at the Nexus of Air Quality and Climate Change (CalNex) study from 15 May to 15 June 2010 in Pasadena CA. Particle pH and water were predicted with t...

AIM This in vitro study evaluated the effect of calcium hydroxide on pH changes of the external medium after intracoronal bleaching. MATERIALS AND METHODS A total of 50 extracted human premolars were prepared and filled with gutta-percha and endodontic sealer. The teeth were randomly divided into five groups according to the bleaching agents employed: (a) Sterile cotton pellet with distilled ...