Chemical Pollutants in Air, Water, Soil, and Solid Wastes Phần pps

... 1997 by CRC Press LLC © 1997 by CRC Press LLC Handbook of Environmental Analysis Chemical P ollutants in Air, Water, Soil, and Solid Wastes Pradyot Patnaik, Ph.D. LEWIS PUBLISHERS Boca ... therefore, important to examine the type of compounds that are to be analyzed and certain physical and chemical properties of these compounds. Information regarding the st...

Ngày tải lên: 08/08/2014, 00:22

... such interference effect. Remove free chlorine in the sample by adding Na 2 S 2 O 3 solution. In addition, the presence of oxidizing and reducing agents in the sample may interfere ... phenolphthalein alkalinity . In such alkalinity titration, phenolphthalein or metacresol purple may be used as an indicator. On the other hand, the total alkalinity is mea...

Ngày tải lên: 08/08/2014, 00:22

... terminal oxygen atom is replaced by a nitrogen atom. Triazine is a nitrogen heterocyclic ring containing three N atoms in the ring. NCO O (leaving group) R 1 R 2 1. Carbamate NCO O (leaving group) R 1 R 2 2. ... 3 ) occurs in v arying concentrations in groundwater, surface water, and waste water. Its occurrence in waters and sludge is primarily attributed to its formation...

Ngày tải lên: 08/08/2014, 00:22

... may be adhering to it. It is dried in an oven for several hours at 105°C, cooled in a desiccator, and weighed. Heating, cooling, and weighing is repeated until a constant weight is obtained. Alternately, ... POLYCHLORINATED DIOXINS AND DIBENZOFURANS Polychlorinated dibenzo- p -dioxins and dibenzofurans are tricyclic aromatic compounds having the following structures: Chlor...

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... XAD-2. • Monomethylamine interferes in the test; interference is removed by passing air through an impinger containing 0.5% CuCl 2 solution before drawing the air through the solid adsorbent. •A ... Chloroformates and acidic substances (at high concentrations) may interfere in the test. • Detection limit: in the range 0.1 ppb. Air drawn through an impinger containing 4,4 ′...

Ngày tải lên: 08/08/2014, 00:22

... especially in the case of oxidizing and reducing agents in redox reactions. In such reactions, equivalent weight is determined from the change in oxidation number on the element during titration. ... B SAMPLE CONTAINERS, PRESERVATIONS, AND HOLDING TIMES Analyte Container Preservation Maximum holding time Inorganics and microbial tests Acidity P,G Cool, 4°C 14 d Alkalinit...

Ngày tải lên: 08/08/2014, 00:22