Abstract: A urine specimen is preserved from bacterial deterioration as to relative constituents by adding thymol. To the thymol-treated specimen, lithium-solution volume-marker is added, then is divided into two (first and second) separate portions. Thereupon, using the first portion, standard conventional measurements and/or analysis is conducted for total volume, pH/acidity, uric acid, citrate, sodium, and potassium. To the second portion, there is added boric acid and hydrochloric acid, followed by standard/conventional measurement and/or analysis for ammonium ion, citrate, calcium, magnesium, phosphorus, oxalate and sulfate. Thereafter the findings are charted and compared to controls.

Abstract: A method of predetermining the exact weight ratio of the reactants to produce a product and maintain the weight ratio of the reactants to obtain a maximum yield of the product. The method combines weight ratio measurement with infrared absorbance measurements to determine the maximum yield of an alkenyl succinimide product.

Abstract: There is disclosed a method of contacting a peroxide containing substance with non-volatile, alpha-keto acid radiolabeled with --C.sup.14 in the carboxyl group and determining radioactivity evolved .sup.14 CO.sub.2 and thereby calculating the amount of peroxide in the substance.

Abstract: The invention relates to a method and reagent for the determination of peracids. The method is characterized in that the sample solution is mixed with a chromogen, an iodide and, where appropriate, a buffer-containing reagent, and the color reaction is evaluated, e.g., visually or by spectrophotometry.

Abstract: The instant invention is directed to a method for determining the concentration of sulfonate and/or polycarboyxlate compounds in an aqueous solution comprising:(a) adjusting the pH of a portion of the aqueous solution to less than 3.0 when measuring sulfonate concentration or to between 3.0 and 12.0 when measuring polycarboxylate concentration;(b) adding an effective amount of an aqueous solution containing a metachromatic dye to the pH-adjusted portion of Step (a);(c) measuring the absorbance of the admixture resulting from Step (b) at a wavelength between 300 nm and 700 nm; and(d) comparing the absorbance from Step (c) with absorbances of standard samples containing known concentrations of sulfonate and/or polycarboxylate compounds and said effective amount of the dye solution of Step (b), thereby determining the sulfonate and/or polycarboxylate concentration of the portion of Step (a).

Abstract: The present invention provides stabilized compositions of tetrazolium salts for analytical purposes which contain 1 to 10 moles of a complex forming acid which is soluble in polar solvents, per mole of tetrazolium salt. Additionally, the invention provides a process for the detection of reducing materials, wherein a stabilized composition as described is added to a test batch.

Abstract: A method for detecting the presence of carboxylic acids in a specimen is provided. A specimen is contacted with a developing system containing a metal salt reactive with carboxylic acids present in the specimen to form metal-carboxylic acid complexes. Any such complexes are colorimetrically detected by their activity in catalyzing oxidation of a chromogen such as guaiac. The method is useful in detecting intestinal helminth infestation.

Abstract: A method of determining in a discrete analyzer the total sugars content of a tobacco sample containing sucrose, glucose and fructose, comprises the steps of, converting the sucrose to glucose and fructose, enzymatically converting the glucose and fructose to glucose-6-phosphate in the presence of hexokinase, reacting the glucose-6-phosphate with nicotinamide-adenine dinucleotide in the presence of glucose-6-phosphate dehydrogenase to give reduced nicotinamide-adenine dinucleotide, the amount of reduced nicotinamide-adenine dinucleotide produced being directly proportional to the total sugars content of the sample, measuring the concentration of reduced nicotinamide-adenine dinucleotide in the sample, and generating a signal indicative of the concentration of reduced nicotinamide-adenine dinucleotide and hence of the total sugars content of the sample. Deactivation of enzymes by any cyanogen bromide that may be present is prevented by the addition of dithioerythritol to the reaction mixture.

Abstract: A method of forming analyzable adducts in a mixture of compounds by contacting the mixture with a boron reagent having the formula of either ##STR1## where each X and Y is, independently, an alkyl group of 12 or fewer carbons or an aryl group of 6-20 carbons; or BZ.sub.3, where each Z is, independently, an alkyl group of 12 or fewer carbons, or an aryl group of 6-20 carbons.

Abstract: A method for fluorometric analysis of catecholamines characterized in that, after the addition of a catecholamine into a solution of 1,2-diphenylethylenediamine containing an oxidizing reagent at a pH of 4 to 10, the mixture is allowed to stand for more than 1 minute at a temperature of higher than 15.degree. C. to make cateocholamine fluorescent, is disclosed.

Abstract: A continuous process and apparatus for the analysis of a sample containing a peroxycompound in the presence of hydrogen peroxide using known colorimetric techniques, characterized in that a sample is taken continuously, is continuously mixed with a colorimetric reagent and is divided into two streams, and continuous differential colorimetric analysis of the two streams is effected to provided a differential signal, further characterized in that one such stream is heated to such a temperature that the peroxycompound reacts with the colorimetric reagent prior to effecting the differential colorimetric analysis, whereby the differential signal is a measure of the concentration of such peroxycompound. The process and apparatus may be modified in that a third stream is taken not containing any colorimetric reagent, and two differential colorimetric analyses are effected, whereby a further signal is obtained which is a measure of the concentration of the hydrogen peroxide.

Abstract: A method is disclosed for separating and measuring the fluorescence of 4-carboxy-p-terphenyl in crude terephthalic acid formed by the liquid-phase oxidation of p-xylene in a solvent.

Abstract: A quantitative method useful for field monitoring low concentrations of water soluble, polyacrylic acids in aqueous systems containing polyacrylic acids and other soluble ionic materials, such as ionic salts and phosphonates, is provided. The method involves adjusting the pH of the aqueous system to suppress the ionization of the polyacrylic acids followed by selective adsorption and concentration of the polyacrylic acids on a suitable adsorbent. Concentrated polyacrylic acids are then desorbed from the adsorbent and the concentration of the polyacrylic acids in the aqueous system is determined by conventional techniques.

Abstract: A method for the quantitative determination of a chemical species capable of promoting the disproportionation of Hg.sub.2.sup.2+ to Hg.sup.2+ and Hg.degree. in solution which method comprises causing the species to react with a solution comprising Hg.sub.2.sup.2+ to thereby produce a measurable concentration of Hg.degree. in a gaseous phase above the solution, and determining the Hg.degree. present in the said gaseous phase.The method is particularly applicable to the determination of low concentrations (e.g. as low as 0.1 p.p.b.) of SO.sub.2 in gas mixtures, such as air.

Abstract: Boar taint in individual carcasses of uncastrated boars or parts thereof is determined in a fast and simple manner by determining IR-spectrophotometrical transmission data for the individual carcass or part or preferably on a sample from the carcass or part, and comparing the spectral data registered with corresponding data having a statistical relationship to boar taint. A suitable determination is determination of the ratio between the absorptions at two different wave lengths in the range of 1275-1325 cm.sup.-1 in the IR spectrum of the fat sample. A still higher correlation between the particular spectral data and the organoleptic data is obtained when one or more further parameters with statistical correlation to the odor image is/are included, e.g., the concentration of unsaturated fatty acids in the fat of the boar carcass.