Radiation General

B) The multiphoton excitation of electronic levels of atoms and molecules with visible or UV radiation generally leads to ionization. The mechanism is generally a combination of direct, Goeppert-Mayer, and quasi-resonant stepwise processes. Since ionization often requires only two or tln-ee photons, this type of multiphoton excitation is used for spectroscopic purposes in combination with mass-spectrometric detection of ions. 

Thermal Transducers Infrared radiation generally does not have sufficient energy to produce a measurable current when using a photon transducer. A thermal transducer, therefore, is used for infrared spectroscopy. The absorption of infrared photons by a thermal transducer increases its temperature, changing one or more of its characteristic properties. The pneumatic transducer, for example. 

Vacuum Insulation Heat transport across an evacuated space (1.3 X lO"" Pa or lower), is by radiation and by conduction through the residual gas. The heat transfer by radiation generally is predominant and can be approximated by... 

The emission spectrum of the cathode material includes a number of intense, sharp lines arising from transitions between excited states and the ground state, so-called resonance radiation. Generally, only a few resonance lines per element are suitable for quantitative work and there will be variation in the ranges of concentration over which absorbance measurements... 

Unlike ionic polymerizations, radical chain polymerizations have so far been found to occur only with unsaturated compounds. In some cases they can be induced purely thermally, or by means of light or high-energy radiation generally, however, radical initiators such as peroxo compounds, azo compounds, and redox systems are used. 

Polymerization of coatings on electrical conductors and paper and monomers impregnated into wood and concrete. (Machine radiation generally is preferred in applications involving thin materials.)... 

Ordinarily, the photochromic reaction involves a reversible transformation between two species with B having at least one absorption band appearing at longer wavelength than those of A. The activating radiation generally is in the UV region (300 to 400 mm) but could be in the visible (400 to 700 nm). The most prevalent photochromic systems are established to be unimolecular reactions (A — B) and those described in this book correspond to this type. 

GATOR/GCMOM The Gas, Aerosol, Transport, Radiation, General Circulation,... 

USNRC. 1997a. United States Nuclear Regulatory Commission. Standards for protection against radiation, general provisions, definitions. Code of Federal Regulations. 10 CFR 20.1003. 

As with any superficial keratitis, the corneal lesions related to excessive UV radiation generally resolve within 8 to 24 hours. Supportive therapy for mild cases may include topical lubricating agents only, including drops during the day and ointment at bedtime. As with a sunburn, cold compresses applied to the eyes three to four times daily may also provide some symptomatic relief. 

X-ray powder diffraction samples were prepared as previously described, the X-ray dtffraciton pattern (XRDP) being recorded on film using Ni-filtered Cu Ka radiation (General Electric Co. precision camera. Straumanis loading). The program ERaCEL- was used for the refinement of the lattice parameters which incorporates the Nelson-Riley extrapolation function.- The AgMFfi salts (M = Os. Ir, Ru) show... 

The model of a grey Lambert radiator, with a(T) = e(T) can therefore not be applied to the absorption of solar radiation. Rather, it is to be expected that the absorptivities deviate vastly from the tabulated emissivities. These absorptivities as for the absorption of predominantly short-wave solar radiation, generally... 

Infrared Absorption Infrared radiation generally is not sufficiently energetic to cause electronic transitions, but it can induce transitions in the vibrational and rotational states associated with the ground electronic state of the molecule. Four of... 

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