Determination of carbonate

As a final example, the determination of carbon in steels and other metal alloys can be determined by heating the sample. The carbon is converted to CO2, which is collected in an appropriate absorbent trap, providing a direct measure of the amount of C in the original sample. 

Determination of Carbon Monoxide in Automobile Exhaust by FT-IR Spectroscopy, /. Chem. Educ. 1988, 65, 820-823. 

B. Langfoid, L. Latimei, and K. Ash, Determination of Carbon Utilising a HECO TR—12 Mnalycyer, Teledyne Wab Chang Corp., Albany, Oieg., 1977. Ref 38, p. 260. 

Susceptibility to radiation damage must be considered seriously if reference samples are to be calibrated for use in place of absolute systems. For the measurement of absolute C He, H) cross sections, films of polystyrene (CH) (which is relatively radiation hard) have been used successfiiUy, the RBS determination of carbon providing implied quantitation for the hydrogen present in the film. For a durable laboratory reference sample, however, there is much to recommend a known ion-implanted dose of H deep within Si or SiC, where the loss of hydrogen under room temperature irradiation will be neghgible. 

One area of cat cracking not fully understood is the proper determination of carbon residue of the feed and how it affects the unit s coke make. Carbon residue is defined as the carbonaceous residue formed after thermal destruction of a sample. Cat crackers are generally limited in coke burn capacity, therefore, the inclusion of residue in the feed produces more coke and forces a reduction in FCC throughput. Conventional gas oil feeds generally have a carbon residue less than 0,5 wt for feeds containing resid, the number can be as high as 15 wt lf. 

Determination of carbonate by the evolution of carbon dioxide Discussion. The... 

Other examples of analyses for light elements are given in Appendix VI. It is reasonable to expect that the routine determination of light elements by x-ray emission spectrography will eventually include sodium. It seems unlikely to us that the routine quantitative determination of carbon by this method is in sight. (See, however, Appendix V.)... 

Wright, The Rapid Micro Combustion Determination of Carbon, Hydrogen Nitrogen in High Explosives", Explosivst 14 (12), 274-6 (1966) CA 66, 97068 (1967) 43) Anon,... 

There are a number of light stable isotope measurements that provide very important data in the study of paleoclimates to better understand and interpret anthropogenic contributions to present-day climate change (Fritz and Fontes 1980). These measurements involve the determination of carbon and oxygen isotopes in fresh-... 

Roberts JL, Sawyer DT. 1964. Voltammetric determination of carbon monoxide at gold electrodes. J Electroanal Chem 7 315-319. 

The use of nuclear techniques allows the determination of C, N, H, O, and heavier contaminants relative fractions with great accuracy, and of the elements depth profile with moderate resolution (typically 10 nm). Rutherford backscattering spectroscopy (RBS) of light ions (like alpha particles) is used for the determination of carbon and heavier elements. Hydrogen contents are measured by forward scattering of protons by incident alpha particles (ERDA) elastic recoil detection analysis [44,47]. 

Smith PE, Farquhar RM Hancock RG (1991) Direct radiometric age determination of carbonate diagenesis using U-Pb in secondary calcite. Earth Planet Sci Lett 105 474-491 Spalding RF, Mathews TD (1972) Submerged stalagmites from caves in the Bahamas Indicators of low sea level stand. Quat Res 2 470-472... 

On-line SFE-GC finds use especially in petroleum-related applications [54], but has also been applied to polymer additives [47,55]. PBT polymers were extracted at 200 bar and 55 °C for the determination of carbonic acid diphenyl esters and other volatiles, using on-line SFE-GC-MS [47]. Extraction of entrained volatiles is a quality test for some polymers. SFE-GC-FTIR-MS has been employed to reveal the cause of odour of a smelly hose (a plasticiser) [56]. SFE-GC can also profitably be used for the determination of residual solvents in polymers such as benzene, toluene and o-xylene [57]. Oligomers of PE (up to 1000 Da) were determined by GC after supercritical fluid extraction [58]. 

Nicolaescu, I. V., Tardos, G. I., and Riman, R. E., Thermogravimetric Determination of Carbon, Nitrogen and Oxygen in Aluminum Nitride, J. 

Murphy et al. [21] have described an infrared based detector method for the determination of carbon dioxide in seawater. 

Neill et al. [22] have described a headspace gas chromatographic method for the determination of carbon dioxide (fugacity) in seawater. This method requires a small water sample (60 ml), and provides for rapid analysis (2 min). 

Lan and Mottola [14] have presented two continuous-flow-sensing strategies for the determination of C02 in gas mixtures using a special reaction cell. Both approaches are based on the effect of the complex of Co(II) with phthalocyanine as a rate modifier of the CL emission generated by luminol in the absence of an added oxidant agent, which is enhanced by the presence of C02 in the system. This enhancement allows the fast and simple determination of carbon dioxide at ppm levels (v/v) in atmospheric air and in human breath. In the first case, a continuous monitoring system was applied however, because the flow of expired gas is not constant, a discrete sample introduction approach was used in the analysis of C02 in breath. 

Dean WE, Jr. Determination of carbonate and organic matter in calcareous sediments and sedimentary rocks by loss on ignition-comparison with other methods. J. Sediment. Petrol. 1974 44 242-248. 

As titration procedures, compared to some other procedures are relatively insensitive, it is likely that they would only be applied to those types of solid samples where the concentration to be determined is relatively high. Titration methods have been applied to the determination of carbonate, insecticides, total organic carbon and nitrogen in soil, total organic carbon in non-saline sediments and total sulphur in saline sediments. 

Fig. 12.5 Determination of carbon-bonded sulphur, ester sulphate and total organic sulphurfrom analyses of total sulphur, hydriodic acid reduction, extractable inorganic sulphate, HCI digestion and Zn-HCI reduction.

Hedges, J.I., and J.H. Stem 1984. Carbon and nitrogen determinations of carbonate-containing solids. Limnology and Oceanography 29(3) 657-663. 

A test method (ASTM D5291) is available for simultaneous determination of carbon, hydrogen, and nitrogen in petroleum products and lubricants. There are at least three instrumental techniques available for this analysis, each based on different chemical principles. However, all involve sample combustion, components separation, and final detection. 

Determination of Carbon and Nitrogen in Sediments and Particulates of Estuarine/Coastal Waters using Elemental... 

Only one complication to the determination of carbon Ffp has been identified but it illustrates the role of the strongly interacting proton dipolar system, a role which must be examined in even more detail for the non-spinning case (39). 

A method for the determination of carbon-linked methyl groups (and, by extension, used in the analysis of chiral methyl groups in stereochemical studies of enzyme-catalyzed reactions acting on methyl groups). In this procedure, the methyl groups are converted to acetic acid by oxidation of the metabolite with chromic and sulfuric acids. Milder versions are also available. 

Analytical methods for the determination of carbon tetrachloride in biological samples are summarized in Table 6-1. 

It is possible to estimate the influence of the spectrometer on linewidth measurements by convolving the response function with a mathematical model of the line. The resulting curve may be compared with the observed line and the true width inferred. Hunt et al. (1968) have employed corrections of this type supplied by the author in their determination of carbon monoxide self-broadened linewidths. 

This double salt is made easily by dissolving potassium chloride, KC1, and cupric chloride, CuCl2-2H20, in water in the proportion of two molecules of the former to one of the latter and evaporating the solution to crystallization. This salt, as well as the corresponding ammonium salt, is used in the determination of carbon in iron. Iron dissolves in a concentrated solution of the salt, leaving the carbon undissolved, and the latter can be filtered off and estimated by combustion. 

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