Light intensities, high

About 20 kg of scandium (as SC2O3) are now being used yearly in the U.S. to produce high-intensity lights, and the radioactive isotope 46Sc is used as a tracing agent in refinery crackers for crude oil, etc. 

Initiation by Light. Neither Deb (quoted in Ref 19, p 111) nor the writer (Ref 47) could produce detonation of PETN exposed to high-intensity light. The writer used PETN cores at 0.8 to 1.5g/cc, with and without small additions of graphite (in attempts to increase light absorbency), in 1 /4 inch ID plastic holders, and exposed them up to around 25microsec to the radiation of Argon flash bombs (T=29000°K). 

The efficiency of a photochemical process [39] requiring high-intensity light sources, e.g., UV... 

Optic cavitation It is produced by photons of high intensity light (laser) rupturing the liquid continuum. 

The dry complex is exploded by high-intensity light pulses, or by heat or sparks. As a slurry in acetone, it is stable for a week if kept dark [1], The complex explodes violently at 245°C/1 bar and at 195°C/1.3 mbar [2], or on exposure to light [3],... 

The Beer-Lambert law can generally be applied, except where very high-intensity light beams such as lasers are used. In such cases, a... 

Two kinds of nonlinear junctions considered above have different functions with respect to the power of input light beam. The transmittance of the linear/nonlinear junction decreases with input power. The efficiency of the nonlinear action of the structure is greater in narrower waveguides. The transmittance of the junction of nonlinear waveguides has extremes in dependence on the input power but grows up to unity in the limit of high-intensity light beams. 

This involves the application of a pulse of high intensity light of short duration to a solution containing one or more species. In the original Nobel prize winning studies a flash lamp of a few microseconds duration was used. Now a laser pulse is more often utilized and times as short as picoseconds or less may be attained. Several set-ups have been described. Their complexity and cost are related to the time resolution desired. An inexpensive system using... 

As a metal, Pr is hygroscopic (adsorbs water) and tarnishes in the atmosphere. It will react with water to liberate hydrogen. It is soluble in acids and forms greenish salts, along with some other rare-earths. It is used to fabricate the electrodes for high-intensity lights. 

Swedish chemist Carl Gustaf Mosander Silvery, reactive, malleable first of the rare earth elements, whose added electrons are hidden in their atoms interiors as a compound used in high-intensity lighting. 

Optical devices have also been used as transducers. Laser fiber-optics allows high intensity light to travel a long distance using fibrous size carrier. The stable and intense light beam not only provides calibration stability but also makes all the detecting techniques faster and more sensitive. In addition to the UV-VIS absorbance and fluorescence intensity, measurements of multiple reflections, surface plasmon resonance, and total internal reflection fluorescence had recently been used (12, 13, 14). 

D.J. Moore, Thermal Decomposition of Barium Azide , Nature 203, 860—61 (1964) 132) J. Roth, Initiation of Lead Azide by High Intensity Light , JChemPhys 41, 1929—36 (1964) 133) G. Odian et al, Radiation-... 

The writer studied the initiation of Pb Azide by high-intensity light (Ref 9b). He found that the process of initiation was thermal, with thermal expln occurring in a thin layer that was heated by absorbing most of the incident light. He was able to make estimates of the kinetic parameters of Pb Azide based on observed initiation delays and thermal expln theory... 

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