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Pressure of radiation

We wish to determine (a) the behavior of radiation as a gas, (b) the specific heat (at constant volume or pressure) of radiation, and (c) the relation governing the isen tropic process of radiation. [Pg.399]

Pressure, atm pg, partial pressure of radiating gas Heat flow rate, W or Btu/h q-f, total by conduction-convection q, by radiation q,2, net exchange between surfaces 1 and 2 radia-... [Pg.424]

Ashkin A and Gordon J P 1983 Stability of radiation-pressure particle traps an optical Earnshaw theorem Opt. Lett. 8 511-13... [Pg.2480]

The fixed points in the lTS-90 are given in Tabie 11.39. Platinum resistance thermometers are recommended for use between 14 K and 1235 K (the freezing point of silver), calibrated against the fixed points. Below 14 K either the vapor pressure of helium or a constant-volume gas thermometer is to be used. Above 1235 K radiometry is to be used in conjunction with the Planck radiation law,... [Pg.1215]

The 3 Pi/2, 3 P2/2 excited states involved in the sodium D lines are the lowest energy excited states of the atom. Consequently, in a discharge in the vapour at a pressure that is sufficiently high for collisional deactivation of excited states to occur readily, a majority of atoms find themselves in these states before emission of radiation has taken place. Therefore... [Pg.215]

From about 1970, but before the availability of suitable lasers, Parmenter and others obtained SVLF spectra, particularly of benzene, using radiation from an intense high-pressure xenon arc source (see Section 3.4.4) and passing it through a monochromator to select a narrow band ca 20 cm wide) of radiation to excite the sample within a particular absorption band. [Pg.377]

Protein-Based Adhesives. Proteia-based adhesives are aormaHy used as stmctural adhesives they are all polyamino acids that are derived from blood, fish skin, caseia [9000-71 -9] soybeans, or animal hides, bones, and connective tissue (coUagen). Setting or cross-linking methods typically used are iasolubilization by means of hydrated lime and denaturation. Denaturation methods require energy which can come from heat, pressure, or radiation, as well as chemical denaturants such as carbon disulfide [75-15-0] or thiourea [62-56-6]. Complexiag salts such as those based upon cobalt, copper, or chromium have also been used. Formaldehyde and formaldehyde donors such as h exam ethyl en etetra am in e can be used to form cross-links. Removal of water from a proteia will also often denature the material. [Pg.234]

Liquid Level. The most widely used devices for measuring Hquid levels involve detecting the buoyant force on an object or the pressure differential created by the height of Hquid between two taps on the vessel. Consequently, care is required in locating the tap. Other less widely used techniques utilize concepts such as the attenuation of radiation changes in electrical properties, eg, capacitance and impedance and ultrasonic wave attenuation. [Pg.65]

R. P. Eckberg, "Chemistry and Technology of Radiation Curable Sihcone Release Coatings," in D. Satas, ed.,Mdpances in Pressure Sensitive A.dhesives, Satas Associates, Warwick, R.I., 1992. [Pg.65]

The hydrocarbon gas feedstock and Hquid sulfur are separately preheated in an externally fired tubular heater. When the gas reaches 480—650°C, it joins the vaporized sulfur. A special venturi nozzle can be used for mixing the two streams (81). The mixed stream flows through a radiantly-heated pipe cod, where some reaction takes place, before entering an adiabatic catalytic reactor. In the adiabatic reactor, the reaction goes to over 90% completion at a temperature of 580—635°C and a pressure of approximately 250—500 kPa (2.5—5.0 atm). Heater tubes are constmcted from high alloy stainless steel and reportedly must be replaced every 2—3 years (79,82—84). Furnaces are generally fired with natural gas or refinery gas, and heat transfer to the tube coil occurs primarily by radiation with no direct contact of the flames on the tubes. Design of the furnace is critical to achieve uniform heat around the tubes to avoid rapid corrosion at "hot spots."... [Pg.30]

When the partial pressures of the radicals become high, their homogeneous recombination reactions become fast, the heat evolution exceeds heat losses, and the temperature rise accelerates the consumption of any remaining fuel to produce more radicals. Around the maximum temperature, recombination reactions exhaust the radical supply and the heat evolution rate may not compensate for radiation losses. Thus the final approach to thermodynamic equiUbrium by recombination of OH, H, and O, at concentrations still many times the equiUbrium value, is often observed to occur over many milliseconds after the maximum temperature is attained, especially in the products of combustion at relatively low (<2000 K) temperatures. [Pg.516]

Most theories of droplet combustion assume a spherical, symmetrical droplet surrounded by a spherical flame, for which the radii of the droplet and the flame are denoted by and respectively. The flame is supported by the fuel diffusing from the droplet surface and the oxidant from the outside. The heat produced in the combustion zone ensures evaporation of the droplet and consequently the fuel supply. Other assumptions that further restrict the model include (/) the rate of chemical reaction is much higher than the rate of diffusion and hence the reaction is completed in a flame front of infinitesimal thickness (2) the droplet is made up of pure Hquid fuel (J) the composition of the ambient atmosphere far away from the droplet is constant and does not depend on the combustion process (4) combustion occurs under steady-state conditions (5) the surface temperature of the droplet is close or equal to the boiling point of the Hquid and (6) the effects of radiation, thermodiffusion, and radial pressure changes are negligible. [Pg.520]

C y = correction fac tor for pressure broadening of radiation from water vapor. d = particle diameter. [Pg.570]

The laser-Doppler anemometer measures local fluid velocity from the change in frequency of radiation, between a stationary source and a receiver, due to scattering by particles along the wave path. A laser is commonly used as the source of incident illumination. The measurements are essentially independent of local temperature and pressure. This technique can be used in many different flow systems with transparent fluids containing particles whose velocity is actually measured. For a brief review or the laser-Doppler technique see Goldstein, Appl. Mech. Rev., 27, 753-760 (1974). For additional details see Durst, MeUing, and Whitelaw, Principles and Practice of Laser-Doppler Anemometry, Academic, New York, 1976. [Pg.889]

Both factors depend on the respective partial vapor pressures of water and carbon dioxide and upon the distance to the radiation source. The partial vapor pressure of carbon dioxide in the atmosphere is fairly constant (30 Pa), but the partial vapor pressure of water varies with atmospheric relative humidity. Duiser (1989) published graphs plotting absorption factors (a) against the product of partial vapor pressure and distance to flame (Px) for flame temperatures ranging from 800 to 1800 K. [Pg.63]

The emissive power of a fireball, however, will depend on the actual distribution of flame temperatures, partial pressure of combustion products, geometry of the combustion zone, and absorption of radiation in the fireball itself. The emissive power ( ) is therefore lower than the maximum emissive power (E ) of the black body radiation ... [Pg.167]

Steam jet thermocompressors or steam boosters are used to boost or raise the pressure of low pressure steam to a pressure intermediate bettveen this and the pressure of the motive high pressure steam. These are useful and economical when the steam balance allows the use of the necessary pressure levels. The reuse of exhaust steam from turbines is frequently encountered. The principle of operation is the same as for other ejectors. The position of the nozzle with respect to the diffuser is critical, and care must be used to properly posidon all gaskets, etc. The thermal efficiency is high as the only heat loss is due to radiation [5]. [Pg.378]


See other pages where Pressure of radiation is mentioned: [Pg.10]    [Pg.568]    [Pg.387]    [Pg.10]    [Pg.568]    [Pg.688]    [Pg.171]    [Pg.232]    [Pg.10]    [Pg.568]    [Pg.387]    [Pg.10]    [Pg.568]    [Pg.688]    [Pg.171]    [Pg.232]    [Pg.238]    [Pg.416]    [Pg.453]    [Pg.7]    [Pg.65]    [Pg.354]    [Pg.249]    [Pg.100]    [Pg.16]    [Pg.214]    [Pg.190]    [Pg.236]    [Pg.242]    [Pg.117]    [Pg.345]    [Pg.248]    [Pg.765]    [Pg.2308]    [Pg.367]    [Pg.412]    [Pg.359]    [Pg.58]    [Pg.481]    [Pg.405]   
See also in sourсe #XX -- [ Pg.311 ]

See also in sourсe #XX -- [ Pg.387 ]

See also in sourсe #XX -- [ Pg.401 ]




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Radiation pressure

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