Inorganic constituents using

Ash and Inorganic Constituents. Ash may be measured gravimetdcaHy by incineration in the presence of sulfudc acid or, more conveniendy, by conductivity measurement. The gravimetric result is called the sulfated ash. The older carbonate ash method is no longer in use. Ash content of sugar and sugar products is approximated by solution conductivity measurements using standardized procedures and conversion factors. 

Table II summarizes analytical data for dissolved inorganic matter in a number of natural water sources (J3, 9, J 9, 20, 21). Because of the interaction of rainwater with soil and surface minerals, waters in lakes, rivers and shallow wells (<50m) are quite different and vary considerably from one location to another. Nevertheless, the table gives a useful picture of how the composition of natural water changes in the sequence rain ->- surface water deep bedrock water in a granitic environment. Changes with depth may be considerable as illustrated by the Stripa mine studies (22) and other recent surveys (23). Typical changes are an increase in pH and decrease in total carbonate (coupled), a decrease in 02 and Eh (coupled), and an increase in dissolved inorganic constituents. The total salt concentration can vary by a factor of 10-100 with depth in the same borehole as a consequence of the presence of strata with relict sea water. Pockets with such water seem to be common in Scandinavian granite at >100 m depth.

REMTL Recovery of metals Recovery of organics uses direct physical removal methods to extract metal or inorganic constituents from a waste... 

It is customary in analytical chemistry to examine unknown samples by a screening procedure using a multicomponent method like OES or MS in case of inorganic constituents on the one hand and GC or HPLC in case of organic constituents on the other. In this way, an overview can be obtained on the type of constituents and their approximate contents. In many cases it is necessary to get a deeper insight into the sample composition. For this reason, the one or a few constituents have to determine more precisely. 

Extraction with heated water is also possible but is not commonly used to extract inorganic constituents. 

A majority of soil extractions of inorganic constituents are carried out to determine the metal content of a soil sample. In these cases, it is common to use add extracting solutions. Dilute hydrochloric and sulfuric acids are most commonly used. Nitric acid is an oxidizer, so undesired oxidation can occur during the extraction process using this reagent. Phosphate is a natural... 

The presence and concentration of various metallic elements in petroleum coke are major factors in the suitability of the coke for various uses. In the test method (ASTM D5056), a sample of petroleum coke is ashed (thermally decomposed to leave only the ash of the inorganic constituents) at 525°C (977°F). The ash is fused with lithium tetraborate or lithium metaborate. The melt is then dissolved in dilute hydrochloric acid and the resulting solution is analyzed by atomic absorption spectroscopy to determine the metals in the sample. However, spectral interferences may occur when using wavelengths other than those recommended for analysis or when using multielement hollow cathode lamps. 

Refining. After saccharification, the hydrolyzate is clarified by precoat filtration, or possibly membrane filtration, to remove traces of insoluble fat, protein, and starch. Treatment with powdered carbon, granular carbon, and/or ion-exchange resins is then used to remove residual trace impurities, color, and inorganic constituents. The refined hydrolyzate can be dried to a solid product, evaporated to a high dextrose syrup, or processed to crystalline monohydrate or anhydrous dextrose. A typical process for production of crystalline dextrose is shown in Figure 2(7). 

Table I summarizes most of the practical methods used to achieve the concentration of organic compounds from water samples and indicates the utility of each method, the major advantages and disadvantages, and selected reference citations (3-33). These methods have been discussed previously in more detail (3). Although the methods focus primarily on trace organic chemicals, many of the principles and concerns apply to inorganic constituents as well.

The cross-sectional flow velocity through the resin columns was maintained at 10 cm/min. The columns were each rinsed with 2.5 bed volumes of 1 M HC1 followed by 2.5 bed volumes of distilled water to remove metallic oxides and other inorganic constituents. Finally, the organic components were eluted with 2.5 bed volumes of 95 ethanol. Ethanol was selected as the eluent because it seemed to be the best choice as a solvent tolerated by animals used in proposed biological tests. 

Transition metal acetylides combine the properties of acetylenes with those of the transition metals, offering flexibility in the tuning of structural and electronic properties of both the organic and inorganic constituents. Optimization of the molecular and bulk crystalline properties is envisaged to lead to a new class of useful nonlinear optical materials. 

Minerals. Determinations of inorganic constituents (e.g. total ash, alkalinity of the ash) are classical methods for estimating juice content of citrus juices and beverages. Refinements were made to correct for inorganic sulfites, benzoates and phosphates used as adulterants or preservatives (34). 

In order to sieve samples that are to have their inorganic constituents determined, the soil is ground to pass through a nylon sieve meeting the requirements of BS 410i77. This avoids sample contamination associated with the use of metallic sieves. When sieving samples prior to the determination of organic constituents, a metal sieve may be used provided it does not react with the determinand of interest. 

It is most valuable for meaningful results to characterize DOM within the matrix of the sample concerned. However, for most analytical methods, either the DOC concentration is too low or there are interferences with the inorganic constituents. Therefore, a pretreatment of the sample is often needed. Concentration techniques often used are shown in Table 10.3. Some of the methods applied also lead to a concentration of the inorganic water constituents that may interfere with the analytical method and therefore have to be removed. However, these techniques often lead to a fractionation of the original DOM. 

Hydroxyapatite (HAP), the molecular formula of which is Ca5(P04)3(0H) or Caio(P04)6(OH)2, is the major inorganic constituent in bone, teeth, etc. in the human body. HAP has essentially the same chemical composition and crystalline structure as those of human bone and so has good bio-compatibility. For a long time, it has been widely used as a sclerotin material in setting broken bone, filling teeth, etc. [215]. In addition, HAP can also be used as a food additive and moisture-sensitive element, etc. 

In view of the wide variety and concentrations of inorganic constituents in aquatic environments, there are a great number of analytical techniques used to determine these compounds. They include... 

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