Gravimetric determination of total

ASTM D-5368. Standard Test Methods for Gravimetric Determination of Total Solvent Extractable Content (TSEC) of Solid Waste Samples. 

Gravimetric Determination of Total Polar Material in Athabasca Bitumen"... 

The on-line piezoelectric system of Fig. 7.18C was used for the quantitative gravimetric determination of total fat in foods. The extract obtained by rinsing the cryogenic trap with -hexane was aspirated to the low-pressure injection valve of the FI system, which injected the extract into an n-hexane carrier that drove the injected plug to the flow-cell for monitoring with the aid of an At-Cut 10 MHz piezoelectric quartz crystal coated with gold plated electrodes. The throughput and relative standard deviation thus achieved were 6 samples/h and 2.3%, respectively [120]. 

Ln(II) in LnFj Ln(II) were determined after samples dissolution in H PO in the presence of a titrated solution of NFI VO, which excess was titrated with the Fe(II) salt. It was found that dissolution of the materials based on CeF CeFj in H PO does not change the oxidation state of cerium, thus phosphate complexes of Ce(III, IV) can be used for quantitative spectrophotometric determination of cerium valence forms. The contents of Ln(II, III) in Ln S LnS may be counted from results of the determination of total sulfur (determined gravimetric ally in BaSO form) and sum of the reducers - S and Ln(II) (determined by iodometric method). 

No satisfactory direct gravimetric procedure is available but nitrite can be oxidised to nitrate by permanganate or cerium(IV) and then determined in that form. The determination of total nitrate + nitrite is an important analysis, e.g. for soil samples. Nitrite may be destroyed using urea, sulphamic acid or hydrazine sulphate the reaction with the former is ... 

MDHS 14 General method for the gravimetric determination of respirable and total dust MDHS 15 Carbon disulphide MDHS 16 Mercury vapour in air Laboratory method using hopcalite adsorbent tubes, and acid dissolution with cold vapour atomic absorption spectrometric analysis MDHS 17 Benzene in air Laboratory method using charcoal adsorbent tubes, solvent desorption and gas chromatography MDHS 18 Tetra alkyl lead compounds in air Continuous on-site monitoring method using PAC Check atomic absorption spirometry... 

MDHS14 General methods for the gravimetric determination of respirable and total inhalable dust. 

Cadmium and inorganic compounds of cadmium in air (atomic absorption spectrometry). Cadmium and inorganic compounds of cadmium in air (X-ray fluorescence spectroscopy). Chromium and inorganic compounds of chromium in air (atomic absorption spectrometry). Chromium and inorganic compounds of chromium in air (X-ray fluorescence spectroscopy). General methods for the gravimetric determination of respirable and total inhalable dust. Carbon disulphide in air. 

Determination of Total Oil. The Clevenger hydrodistillation method was used for total oil determination (15). Forty gram samples were distilled for 3i hours. However, due to limited availability, some sample sizes were restricted to 20 grams. Volumetric readings were multiplied by the oil density to arrive at the gravimetric values. All samples were analyzed in duplicate. 

The total sulfur content of gasoline is very low, and knowledge of its magnitude is of chief interest to the refiner who must produce a product that conforms to a stringent specification. Various methods are available for the determination of total sulfur content. The one most frequently quoted in specifications is the lamp method (ASTM D-1266, IP 107), in which the gasoline is burned in a small wick-fed lamp in an artificial atmosphere of carbon dioxide and oxygen the oxides of sulfur are converted to sulfuric acid, which is then determined either volumetricaUy or gravimetrically. 

Solubility. Solubility-based gravimetric quantification of total cellulose, hemicellulose, and lignin has been by far the most commonly used method for determination of the bulk composition of both archaeological and other old woods. These techniques were developed by wood chemists to isolate, characterize, and quantify the major components of sound wood (3). Although the details of the various isolation methods are beyond the scope of this review, the procedures are based on physical isolation via selective solubilizations of other components, followed by weighing of the residue. 

Analysis of dietary fiber. Total dietary fiber including both water-soluble and water-insoluble components was analysed with an enzymic method as described by Asp et al. (18). The dietary fiber was characterized by gas-liquid chromatographic assay of monosaccharides after acid-hydrolysis and gravimetric determination of acid insoluble lignin. Uronic acids were assayed with a decarboxylation method. These analyses were performed as described by Theander and Aman (19). 

The electrical charge of emulsion droplets was determined via zeta-potential measurement by electrophoretic light scattering. The oil droplet size of the emulsions was analysed by static light scattering after dilution of the emulsion to the required optical density or, in the case of spray-dried particles, after dissolution of an aliquot of the microcapsules. Microencapsulation efficiency was calculated from total oil content in the formulation and the gravimetric determination of the oil extracted from the microcapsules with petrol ether [62]. 

Procedure Gravimetric Method for Determination of Total Inorganic Salts in Anionic Surfactants (Alcohol Insoluble Matter)... 

In most analytical procedures for determining the total phosphoms content (normally expressed in terms of P20 ), the phosphates are converted to the orthophosphate form. Typically, condensed phosphates are hydrolyzed to orthophosphate by boiling in dilute mineral acid (0.1 N). The orthophosphate is then deterrnined by gravimetric or spectrophotometric methods. For gravimetric deterrnination, insoluble phosphomolybdates (or magnesium ammonium orthophosphate) is formed. 

Volumetric analysis The determination of the amount of a particular gas in a mixture of gases, as the percentage of the total volume. See Gravimetric analysis. 

The reduction procedure described above was carried out in a static system in order to facilitate determination of the extent of reduction in situ. The reduction was monitored gravimetrically using a microbalance (Cl Electronics MK II) and volumetrically by measuring the decrease in hydrogen pressure. Total surface areas were determined by the BET method using nitrogen at 77 K. 

Gravimetric Properties—The important equations pertaining to suspensions have been developed in Chapter 4 in conjunction with the determination of particle-size. The density of the suspension is readily apparent in the characteristic suspension equation developed there, but will be repeated for the sake of completeness. Let W be the total weight of the particles and p their density if the volume of the suspension is designated as V, and if the suspending fluid is water, then the specific gravity [Pg.344]

By the salinity of sea water is understood the number of grams of total salts in 1000 grams of the water. This may be determined gravimetrically or volumetrieally, the latter method being the most usual, the chlorine being determined, and from it the total salts calculated. This method of course implies suitable laboratory facilities, and if these arc not available the water must be stored until such time as it can be tested. To obviate this difficulty attempts have been made to determine salinity by electric conductivity measurements. By employing a standard sea water and comparing its conductivity with that of the unknown samples, it is claimed that very accurate results are easily obtained at sea or under conditions entire unsuitable for ordinary laboratory work.1... 

Gravimetric determinations on coacervate systems have indicated that about 35% of the total macromolecules in the system were incorporated into the coacervate drops. This information, combined with the mass balance data above, indicates that the coacervates were approximately 66% kappa-casein and 34% gum arabic. 

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