Infrared gas analyzer

Rottenbacher, L., Behlau, L. and Bauer, W., The application of infrared gas analyzers for the fast determination of kinetic parameters for ethanol production from glucose, ]. Biotech., 2 (1985a) 137-147. 

Fig. 15.1. Concentrations of carbon dioxide were measured with a continuously recording nondispersive infrared gas analyzer at Mauna Loa Observatory, Hawaii. The dots indicate average monthly concentrations. (Reprinted with permission from B. Hileman, Carbon dioxide levels in the atmosphere are increasing exponentially, Chem. Eng. News, April 27,1992. pp. 7-19. Copyright 1992 American Chemical Society.)...

Figure 2. Inhibition and recovery of photosynthetic rate in corn with 3 successive exposures to atrazine [Illustrated by one representative infrared gas analyzer trace, + and - refer to presence or absence of atrazine]. "Reproduced with permission from Ref. 19. Copyright 1981, Weed Science Society of America". ...

FIGURE 1.11 Monthly average concentration of carbon dioxide in dry air observed at Mauna Loa Observatory, Hawaii from March 1958 to April 1995. Note The measurements were made with a continuously recording non-dispersive infrared gas analyzer. The smooth curve fit is a fit of the data to a four harmonic annual cycle which increases linearly with time plus a spline fit of the interannual component of the variation. From Whorf (1996). 

Continuous determination of carbon monoxide and carbon dioxide in the flue gas, by means of an infrared gas analyzer, has been reported to be an effective method for operating control, as well as for calculation of yields (307). 

A mixed air with CO2 was used for aeration at the bottom of the reactor. Gas flow rate was 0.5L min, not otherwise stated. COj concentrations in the supply and exhaust gases were measured by infrared gas analyzer (VIA-510, Horiba, Ltd.) and used to estimate CO2 removal. 

Purification of exhaust from HFG 427A gasoline engine without additional secondary air was tested with 6.25 kg of catalyst A. The catalyst was packed in a stainless steel converter which was connected to the exhaust outlet. The contents of CO and HC were measured by an RI503 TH-S CO/HC infrared gas analyzer (Japan). Simulated tests of different rotational speeds of the engine were carried out as indicated in Table 6. 

One interesting example of infrared analysis is an infrared gas analyzer used to determine breath-alcohol levels of motorists [7]. 

Kimmig, L., Krause, R, Ludwig, M. and Schmidt, K. (2000) Non-dispersive infrared gas analyzer , US Patent, US 6166383A. 

Various conventional medical applications for infrared gas analyzers have been described in the literature continuous analysis of COj in respired air (Domhorst et a/., 1953) alveolar CO2 measurement (Collier et al., 1955) measurement of CO2 in respired gas mixtures (Cullen et al., 1956) measurement of CO2 in respired gases containing cyclopropane and ether (Linde and Lurie, 1959) and application to anesthesia and respiratory physiology (Powell, 1965). 

Many examples of biological applications of the infrared gas analyzer have been mentioned by Hill and Powell (1968). Carbon dioxide production by locusts has been studied by Hamilton (1959, 1964). Romijn and Lokhorst (1961) examined expired air of a hen for CO2 in studying the hen s heat-regulating mechanism. The CO2 resulting from the combustion of small amounts of organic carbon in fresh and saline water has been measured by Montgomery and Thom (1962). 

In confined spaces it is necessary to keep the concentration of CO from automobile exhaust down to acceptable limits. Therefore, CO infrared gas analyzers have been installed on a large scale in such places (e.g., tunnels, parking areas, etc.). In medicine, respiratory units for lung-function investigations have used infrared analyzers. The use of infrared methods for qualitative and quantitative information on a variety of gases and vapors has been discussed earlier in this chapter in connection with anesthesiology and toxicology applications. 

Biologically important industrial uses of infrared gas analyzers are the measurement of air pollution and the monitoring of atmospheres (fruit and crop production and storage). It is interesting to note that the use of a COj blanket inhibits deterioration of a banana cargo and apples stored in an atmosphere containing 1000 ppm v/v CO2 will keep almost indefinitely. 

Austin and Longden (1967) have described an apparatus for the measurement of rates of photosynthesis of leaves. In principle, the method consisted of interrupting the flow of air over a leaf for 15 sec, during which time air containing 002 was passed over it. The amount of C taken up by the leaf was then measured and the results were compared with those obtained by means of an infrared gas analyzer. There were discrepancies between the results, the chief cause of which appeared to be preferential fixation of by the leaves and loss of respiratory at low intensities of light. 

Richardson (1967) has used an infrared gas analyzer to follow CO 2 exchange (dark respiration and net photosynthesis) through the first 248 hr of germination of cotton seeds. 

Infrared gas analyzers have been used to record differential ppm levels of CO2 and water vapor in the study of photosynthetic mechanisms in investigations of plant growth, and COj has been monitored in the effluent air from bacterial cultures. 

Sparling and Alt (1966) have measured carbon dioxide concentrations in the atmosphere of several Ontario woodlands with an infrared gas analyzer. They found little evidence of seasonal variation in the concentration of carbon dioxide. Measurements over 24-hr periods revealed the existence of high concentrations, frequently exceeding 500 parts per million at night during midsummer. The high concentrations dropped rapidly at sunrise. These workers were not able to confirm the existence of the extreme stratification of carbon dioxide which had been reported by earlier workers. 

Gas exchange measurements. Photosynthetic CO2 gas exchange rate (CER) measurements were made with an ADC infrared gas analyzer. Carbon reduction rates for early (0600-0950 or 1000), midday (1000 or 0950-1700 or 1850 or 1900), late (1700 or 1850 or 1900-2150) and all day were calculated by integrating the CER area over that time period for the 9 plants of each biotype. 

A infrared gas analyzer and an open steady state system. Chi fluorescence was measured at 20 C using a pulse amplitude modulated fluorometer (4). Fluorescence measurements were made after leaves used in the gas exchange studies were dark adapted for 90 min. Changes in the ratio of the maximum variable fluorescence (Fvm) to initial fluorescence (Fo) were evaluated in terms of increases in Fo/chl resulting from uncoupling of PSII antenna (5) and decreases in Fvm/chl due to photoinhibition (6). 

Although normal relationships of net photoi thesis (P ) vs, stomatal conductance (g,tom) were obtainable by plotting the combined data from infrared gas analyzer studies, an imconventional relationship of P et vs. internal CO2 concentration (Q) was seen when individual gas exchange measiirements were plotted (Fig. 1). The correlation of P vs. C was negative when stomatal conductances were low (i.e. < 0.11 mol m s0. 

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