Temperature of light

As the superheat-limit temperature of light hydrocarbons can be closely approximated as 0.89 times the critical temperature, an equivalent statement would be... 

Figure 12.12 Ignition temperature of light alkanes over a Pt catalyst as a function of the combustion stoichiometry [136].

Similarly, larger Pt particles were more active than smaller ones in xylene combustion. The shift to lower temperatures of light-off curves with increasing Pt particle size, in the particle size range studied, suggests that toluene and xylene combustion was a Pt-structure-sensitive reaction, as occurs with benzene combustion on Pt/AEOB [70]. In the case of xylene combustion, the catalysts... 

Kelvin temperature scale An absolute temperature scale, in which the unit is the Kelvin (K), defined as 1/273.16 of the temperature difference between absolute zero (OK) and the triple point of water. K = °C -h 273. This scale is used to describe the correlated color temperature of light sources and illuminants in color designations and color rendition. Symbol K. See correlated color temperature and Kelvin. Kelvin is used extensively in gas laws and calculation for expansion of gases. Theoretically, all molecular motions cease at OK or absolute zero temperature. Paint pigment, drying oils, polymers, resins, naval stores, cellulosics esters, and ink vehicles, vol 3. American Society for Testing and Material, Conshohocken, PA, 2001. 

The temperature of solar energy (sunlight) reaching the earth is approximately 6000 °C. (The temperature of light depends on the intensity of the colors, (wavelengths), not how hot it feels )... 

Fig. 2.18. Dependence of the critical temperatures of light scattering (tuibidity) in the PPTA-H2SO system on the concentration of polymer [46].

There have been a few other experimental set-ups developed for the IR characterization of surfaces. Photoacoustic (PAS), or, more generally, photothemial IR spectroscopy relies on temperature fluctuations caused by irradiating the sample with a modulated monocliromatic beam the acoustic pressure wave created in the gas layer adjacent to the solid by the adsorption of light is measured as a fiinction of photon wavelength... 

Place a mixture of 30 g. of 3 5-dinitrobenzoic acid (Section IV,168 and 33 g. of phosphorus pentachloride in a Claisen flask fit a reflux condenser into the short neck and cork the other neck and side arm (compare Fig. Ill, 31, 1). Heat the mixture in an oil bath at 120-130° for 75 minutes. Allow to cool. Remove the phosphorus oxychloride by distillation under reduced pressure (25°/20 mm.) raise the temperature of the bath to 110°. The residual 3 5-dinitrobenzoyl chloride solidifies on cooling to a brown mass the yield is quantitative. Recrystallise from carbon tetrachloride the yield is 25 g., m.p. 67-68° and this is satisfactory for most purposes. Further recrystallisation from a large volume of light petroleum b.p. 40-60°, gives a perfectly pure product, m.p. 69 -6°. 

Fluorine and its compounds are used in producing uranium (from the hexafluoride) and more than 100 commercial fluorochemicals, including many well known high-temperature plastics. Hydrofluoric acid etches the glass of light bulbs, etc. Fluorochlorohydrocarbons are extensively used in air conditioning and refrigeration. 

A mixture of 0.25 mol of l,4-diethoxy-2-butyne (see Chapter VIII-6, Exp. 8) and 100 ml of dry diethyl ether was cooled at -45°C. A solution of 0.55 mol (note 1) of ethyllithium (note 2) (see Chapter II, Exp. 1) in about 450 ml of diethyl ether was added in 30 min. The temperature of the mixture was kept between -45 and -35°C. After the addition the mixture was stirred for an additional 20 min at -40°C. The light brown solution was then poured into 500 ml of ice-water, which had been saturated with nitrogen (note 3). After shaking the upper layer was separated off and the agueous layer was extracted twice with small portions of diethyl ether. 

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