Volatilization measurement

Coal tar pitch volatiles measurement of particulates and cyclohexane soluble material in air Lab method using filters and gravimetric analysis 68... 

Three methods were used in this research to measure the extent of binding of organic pollutants to dissolved humic materials. They were equilibrium dialysis, solubility measurements and changes in sorption behavior in the presence of humic materials. Other authors have used solubility measurements, ultrafiltration and volatilization measurements. The methods will be described in the following paragraphs. 

The difference between the concentration in the ultra-filtered water and the concentration inside the ultrafiltration cell is therefore a measure of the bound concentration. Griffin and Chian7-7-, Hassett 7-, and Diachenko have used volatilization measurements to determine the extent of binding of pesticides and pollutants to dissolved humic materials. In these experiments either the rate of gas stripping of a compound or its equilibrium vapor pressure is measured in the presence and absence of humic materials. The results obtained can be manipulated in such a way to determine the percentage of the pollutant bound. 

Sodium Hydroxide and Sodium Acetate Effect on NH Volatility. Ammonia volatility measurements at various concentrations of so-dium hydroxide and sodium acetate at 80°C are given in Tables 23 and 24 respectively. Data on the effect of sodium hydroxide were measured using an ammonia probe from Orion Research Company. 

Ingebrethsen BJ, Lyman CS, Coleman WM III, Nelson PR (1991) Smoke nicotine volatility measurement methods. Available from http //ltdlimages,library,ucsf,edu/imagest/t/n/y/tny93d00/ Stny93d00,pdf, Accessed 19 July 2007... 

In this paper, the volatilization of five organophosphorus pesticides from model soil pits and evaporation ponds is measured and predicted. A simple environmental chamber is used to obtain volatilization measurements. The use of the two-film model for predicting volatilization rates of organics from water is illustrated, and agreement between experimental and predicted rate constants is evaluated. Comparative volatilization studies are described using model water, soil-water, and soil disposal systems, and the results are compared to predictions of EXAMS, a popular computer code for predicting the fate of organics in aquatic systems. Finally, the experimental effect of Triton X-100, an emulsifier, on pesticide volatilization from water is presented. 

When the solute is only sparingly soluble but volatile, measuring the partial vapour pressure may help to determine d/i. For the dilute systems under consideration Dalton s law for the pressure in the mixture, (p + P W = RTln + n ), see 11.2.17.3), is valid. Then we may use 11.2.17.191 for the chemical potential ... 

Volatility measures evaporative loss by the Noack test, or its simulation, limited to 13% (15% for lighter grades), reflecting the tightened limits since first introduced in API CH-4 of 15-20%, according to grade. 

Selection from set A of those substances that may reach the human environment at exposure levels that may be significant (set B). Set B should include substances that may affect environmental processes of immediate importance to human health, such as the activity of sewage degrading organisms. Assessment of probable exposure levels should take into account such data as production, use and disposal quantities, octanol-water partition coefficients and bioaccumulation measurements, volatility, measures of persistence and biodegradability, probable environmental mobility, and major ecological effects. 

Selby, T. W., et al., A New Approach to the Noack Test for Volatility Measurement, SAE International Fuels Lubricants Meeting and Exposition, Philadelphia, PA, 1993. 

As equations (2.315) and (2.316) show, Henry solubility coefficient (H, ) is proportionate to the value of saturated vapour pressure, which serves the volatility measure of nonpolar components. That is why Donald Mackay and Yang Shui (1981) proposed using it for the classification of nonpolar components by volatility ... 

Headspace analysis in series with gas chromatography and mass spectrometry has indicated no emissions from the experimental non-fugitive catalysts mentioned in this paper. Emissions from the fugitive control catalysts were measured and identified. These results support the fact that these experimental catalysts will result in no VOC emissions which will ultimately yield no amine fogging and no vinyl staining from the final polyurethane foam article. Additional volatility measurements have indicated that these experimental catalysts volatilise 3 to 10 times less than the current industry standards (Dabco 33LV and Dabco BL-11) in the temperature range of 0 °C to 150 °C. 

Volatility Measure of the ease of a substance to vaporize VOx Vanadia aerogels VTMS Vinyltrimethoxysilane... 

The percentage of a chemical that will evaporate at ordinary temperatures. A high volatile percentage may mean there is more risk of explosion, or that dangerous fumes can be released. Evaporation rates are a better measure of the danger than the percent volatile measure. 

Figure 12. Volatility measurements for Glass 73 at 750°C and 650°C in different atmospheres.

Huffman JA, Docherty KS, Aiken AC, Cubison MJ, Ulbrich IM, DeCarlo PF, Sueper D, Jayne JT, Worsnop DR, Zieann PJ, Jimenez JL (2009) Chemically-resolved aerosol volatility measurements from two megacity field studies. Atmos Chem Phys 9 7161-7182... 

An WJ, Pathak RK, Lee BH, Pandis SN (2007) Aerosol volatility measurement using an improved thermodenuder application to secondary organic aerosol. J Aerosol Sci 38(3) 305-314. doi 10.1016/j.jaerosci.2006.12.002... 

Huffman JA, Ziemarm PJ, Jayne JT, Worsnop DR, Jimenez JL (2008) Development and characterization of a fast-stepping/scanning thermodenuder for chemically-resolved aerosol volatility measurements. Aerosol Sci Technol 42(5) 395-407... 

Lube oil volatility is a measure of oil loss due to evaporation. Noack volatility measures the actual evaporative loss which is grade dependent, and a function of molecular composition and the efficiency of the distillation step. The volatility is generally lower for higher viscosity and higher VI base stocks. The gas chromatographic distillation (GCD) can be used to measure the front end of the boiling point curve and may be used as an indication of volatility, e.g. 10% off at 375°C. 

The data in Table 2.2 can be conv ted into certain empirical performance characteristics as shown in Table 2.3. In these empirical performance characteristics, hydrogen/carbon (H/Q and oxygen/carbon (0/C) atomic ratios from the ultimate analysis are used as volatility measures along with the volatile/fixed carbon (V/FC) ratio from the proximate analysis. The H/C and V/FC ratios are the dominant volatility measures O/C is of less significance but is not insignificant in assessing fuel volatility. 

The volatility measures lead to significant considerations regarding petroleum coke structiue and reactivity. Traditional methods of fuel analysis provide significant insights as shown above more detailed analyses yield additional measures of significance. 

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