Carbon dioxide measurements

Fig. 18. Diffusion coefficient D12 for hydrogen+carbon dioxide. measure-...

Pearman, G. I. and Beardsmore, D. J. (1984). Atmospheric carbon dioxide measurements in the Australian region Ten years of aircraft data, Tellus, Ser. B, 36,1-24. 

In the authors experience, the amount of carbon dioxide in 10 microliters of blood can readily be determined by adding the blood to an acid, through which bubbles an inert gas. The CO2 is then brought into the field of a long cuvette, of approximately 20" in length, and the carbon dioxide measured at the near infrared with a filter instrument. Instrumentation can be designed readily for measurement of the carbon dioxide content of as little as 1 l of plasma with this principle at the rate of approximately 40-60 per hour. 

Andrew Dickson (Chair) is an Associate Professor-in-Residence at the Scripps Institution of Oceanography. His research focuses on the analytical chemistry of carbon dioxide in sea water, biogeochemical cycles in the upper ocean, marine inorganic chemistry, and the thermodynamics of electrolyte solutions at high temperatures and pressures. His expertise lies in the quality control of oceanic carbon dioxide measurements and in the development of underway instrumentation for the study of upper ocean biogeochemistry. Dr. Dickson served on the NRC Committee on Oceanic Carbon. He is presently a member of the IOC C02 Advisory Panel and of the PICES Working Group 13 on C02 in the North Pacific. 

In principle, isotope dilution could be used to measure the rate of production of water or carbon dioxide by measuring the rate at which the administered " C02 or was diluted. In practice, however, there are difficulties. In the case of water, the amount produced is small compared with the mass of body water, so that the changes in the content of isotope would be too small to measure accurately. The problem with carbon dioxide measurements is the need to take frequent samples because carbon dioxide is rapidly excreted. Two methods have been developed that overcome these problems (see Elia Livesey 1992). 

A scientist combusted 5.000 grams of pure acetylsalicylic acid and produced 2.004 g of water and 6.21 L of dry carbon dioxide, measured at 770. mm Hg and 27°C. Calculate the mass (in grams) of each element in the 5.000 g sample. 

Figure 11.3. (a) Viscosity of PDMS melts swollen with carbon dioxide measured as a function of shear rate and carbon dioxide content at 50 °C. (b) Master viscosity curve produced by applying concentration-dependent scaling factors (see text). A Pure PDMS, 4.84 wt % C02, O 9.03 wt % C02, 14.4 wt % C02 A 20.7 wt % C02. Data denoted by are Newtonian viscosity measurement for pure PDMS. Data from Gerhardt (1994). 

The hydrate and phenol clathrate equilibrium data of the water-carbon dioxide, phenol-carbon dioxide, and water-phenol-carbon dioxide systems are presented in Table 1 and depicted in Figure 2. In order to establish the validity of the experimental apparatus and procedure the hydrate dissociation pressures of carbon dioxide measured in this work were compared with the data available in the literature (Deaton and Frost [7], Adisasmito et al. [8]) and found that both were in good agreement. For the phenol-carbon dioxide clathrate equilibrium results, as seen in Figure 2, the dramatic increase of the dissociation pressures in the vicinity of 319.0 K was observed. It was also found in the previous study (Kang et al. [9]) that the experimental phenol-rich liquid-phenol clathrate-vapor (Lp-C-V) equilibrium line of the binary phenol-carbon dioxide system could be well extended to the phenol clathrate-solid phenol-vapor (C-Sp-V) equilibrium line (Nikitin and Kovalskaya [10]). It is thus interesting to note that a quadruple point at which four individual phases of phenol-rich liquid, phenol clathrate, solid... 

VoL. OF Carbon Dioxide Measured UNDER Normal Conditions. 

The capacity of the pumping system is usually measured in pounds (or kilograms) per minute of carbon dioxide measured at the pump inlet. The open vessel volume multiplied by the density of the carbon dioxide at the system operating conditions will determine the amount of carbon dioxide needed to fill the vessel and the time to make one vessel exchange. The dilution theory thus provides a first estimate of the necessary pump characteristics. However, because pump capacity has a major impact on system cost, it is very important to determine experimentally the actual required cycle to provide the cleanliness levels need. Most suppliers have facilities to assist in obtaining this information. 

Atmospheric carbon dioxide measurements as Manna Loa, Hawaii. These measurements show annual cycles resulting from seasonal variation in carbon dioxide fixation by the Calvin cycle in terrestrial plants. Much of this fixation takes place in rain forests, which account for approximately 50% of terrestrial fixation. [Dennis Potokar/Photo Researchers.]... 

The obvious alternative to wet oxidation would be some variation of the long familiar dry combustion methods, where the sample is heated to 600°-900°C, usually in a stream of oxygen or in the presence of an oxidizer and the resulting carbon dioxide measured in some manner. While this method has worked admirably through the years for a variety of materials, seawater poses some special problems. Some of these problems have already been discussed. The presence of carbonate in the seawater makes an acidification and carbonate removal step necessary, thus also removing the volatile fraction, and the low concentration of DOC limits the permissible sample size. 

ConwayT.J.,Tans P., Waterman L.S.,Thoning K.W., Masarie K.A., Gammon R.H. (1988) Atmospheric carbon dioxide measurements in the remote global troposphere. Tellus 40B, 81-115. 

Figure 9. Comparison of the rise profile and gel" profile of Formulation A with the evolution of carbon dioxide measured by infrared absorbance at 2320 cm 1.

Dissolving 3.00 g of an impure sample of calcium carbonate in hydrochloric acid produced 0.656 L of carbon dioxide (measured at 20.0°C and 792 mmHg). Calculate the percent by mass of calcium carbonate in the sample. 

Propane (C3H8) burns in oxygen to produce carbon dioxide gas and water vapor, (a) Write a balanced equation for this reaction, (b) Calculate the number of liters of carbon dioxide measured at STP that could be produced from 7.45 g of propane. 

R.J. Koestler, S. Sardjono and D.L. Koestler, Detection of insect infestation in museum objects by carbon dioxide measurement using FTIR, Int. Biodeter. Biodegr., 2000, 46, 285-292. 

WMO, Environmental Pollution Monitoring and Research Programme. (1987). Report of the NBS/WMO Expert meeting on Atmospheric Carbon Dioxide Measurement Techniques, Gaithersburg, MD, USA, June 1987, WMO TD-No. 51, Geneva. 

The EPA Method 6 provides procedures for measuring sulfur dioxide emissions from stationary sources where the gas sample is extracted from the exhaust stack. Ammonia, water-soluble cations, and fluorides cause interferences with SOx measurements. Method 6A concerns sulfur dioxide, moisture, and carbon dioxide measurements from fossil fuel combustion sources by chemically separating the SO2 and CO2 components, where different reagent chemicals are used. Method 6C discusses the use of instrument analyzers to measure... 

A sample of the mineral was dissolved in excess hydrochloric acid and the solution made up to 100cm with water. During the process 48 cm of carbon dioxide, measured at 23 C and 1 atmosphere pressure, were evolved. 

The record of measurements of atmospheric carbon dioxide concentrations taken at the Mauna Loa Observatory, Mauna Loa, Hawaii, since March 1958. The Mauna Loa record is the longest reliable daily record of atmospheric carbon dioxide measurements in the world. 

The residual sediment after organic solvent extraction was extracted repeatedly with 0.2N NaOH to isolate the fulvic/humic acid fraction. Humic acid was then precipitated with hydrochloric acid to separate it from fulvic acid in the aqueous phase. Fulvic acid was purified by adsorption and subsequent elution from a column of Amberlite resin. Humic acid was purified by redissolving in NaOH and reprecipitation with hydrochloric acid. The residual sediment was then treated sequentially with hydrofluoric acid of increasing concentration to remove the silicates, washed several times with water and then dried to recover protokerogen (Stuermer et al, 1978). Procedure blank for each compound class fraction was dso combusted for carbon dioxide measurement. 

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. 

Figure 2 shows how the surface areas of coals vary with carbon content. Carbon dioxide measures the entire surface area, pore surfaces as well as external surfaces. Nitrogen cannot penetrate the pores (it does not have enough energy at these low temperatures), and so only the external surface area is measured. The surface areas are enormous. 

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