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Specifies a testing method for assessing the influence of the various parameters which can influence brazing during manufacture as a function of clearances. The test piece described gives guidance about the effects of brazing variables on filler metal flow when capillary gaps of different dimensions are used.

Page 1, clause 2, replace the 3rd paragraph by: "Conversely, if the conditions of application of the layer and its density are known, the determination of the mass per unit area (surface density) can permit a calculation of the average mass and an approximate evaluation of the thickness (see clause 9, note, 3rd paragraph)." Clause 5, 1st line: replace "phosphochromic solution…

A yellow complex is formed by reaction of the vanadium present in a test portion with phosphoric acid and sodium tungstate in acid medium. The spectrometric measurement of the absorbance is carried out at a wavelength of about 425 nm. The method is applicable to products having a vanadium content equal to or greater than 3 mg/kg.

1. Scope 1.1 This Recommended Practice describes a procedure for the prediction of sound pressure levels in a large room containing a number of sound sources. This procedure may be used to compute A-weighted, octave, or fractional octave band sound pressure levels over continuous contours, or at specific points, to predict: (a) Sound pressure levels at the design stage; (b) The…

Provides a list of terms and definitions in English and French, applicable to the techniques of processing and assessing black tea for commerce. The terms are classified into: 1. dry leaf (appearance, colour, odour); 2. liquor (taste characteristics, appearance); 3. appearance of infused leaf; 4. method of manufacture; 5. general. Information about grades is included in an annex. Alphabetical…

TBC is added as an oxidation inhibitor to 1,3-butadiene for industrial use. For the determination the inhibitor is separated from the butadiene by evaporation. The residue is dissolved in water and an excess of iron(III) chloride is added. The spectrometric measurement of the absorbance of the yellow-coloured complex is carried out at a wavelength of about 425 nm. The method is applicable to…

The method is applicable to products having carbonyl compounds contents between 0.00025 % (m/m) and 0.01 % (m/m). The principle is based on reaction in acid medium of the carbonyl compounds in a test portion with 2,4-dinitrophenylhydrazine. Formation of the corresponding 2,4-dinitrophenylhydrazones which, after making the solution alkaline, take on a red coloration. Photometric measurement of…

Specifies a method based on the depolymerization of any polymerized silica by treatment with sodium fluoride in the presence of hydrochloride acid resulting in the formation of the oxidized molycdosilicate, followed by the selective reduction of this complex in the presence of oxalic acid and in a sulphuric acid medium, and spectrophotometric measurement of the blue-coloured complex at the…

The principle is based on the conversion of methanol present in a test portion to formaldehyde by oxidation. The oxidation is carried out with a solution of potassium permanganate in phosphoric acid. Reaction of the formaldehyde formed with chromotropic acid (4,5-dihydroxynaphthalene-2,7-disulphonic acid). Photometric measurement of the violet coloration obtained at a wavelength of about 570 nm…

The lead is extracted from a diluted test portion into a solution of diethylammonium diethyldithiocarbamate in xylene. The xylene extract is separated and aspirated into the acetylene/air flame of an atomic absorption spectrometer. The spectrometric measurements are carried out at a wavelength of about 217 nm or, alternatively, about 283 nm. The method is applicable to phosphoric acids having…