Structural Radiation

Gaydon, A.G. and Wolfhard, H.G., Flames, Their Structure, Radiation and Temperature, 4th ed., Ghapman and Hall, London, 1979, Ghapter 6. 

A family of vacuum-tube MMW sources is based on the propagation of an electron beam through a so-called slow-wave or periodic structure. Radiation propagates on the slow-wave structure at the speed of the electron beam, allowing the beam and radiation field to interact. Devices in this category are the traveling-wave tube (TWT), the backward-wave oscillator (BWO) and the extended interaction oscillator (EIO) klystron. TWTs are characterized by wide bandwidths and intermediate power output. These devices operate well at frequencies up to 100 GHz. BWOs, so called because the radiation within the vacuum tube travels in a direction opposite to that of the electron beam, have very wide bandwidths and low output powers. These sources operate at frequencies up to 1.3 THz and are extensively used in THZ spectroscopic applications [10] [11] [12]. The EIO is a high-power, narrow band tube that has an output power of 1 kW at 95 GHz and about 100 W at 230 GHz. It is available in both oscillator and amplifier, CW and pulsed versions. This source has been extensively used in MMW radar applications with some success [13]. 

The mechanical properties exhibited by a polymer after irradiation are a complex function of molecular weight and molecular weight distribution and the number and type of new structures formed. Thus, it is difficult to draw structure/radiation resistance conclusions from the change in the mechanical properties alone. However, the changes in mechanical properties are direct indications of the ultimate usefulness of the polymer in a radiation environment. 

A.G. Gay don and H.G. Wolfhard, Flames Their Structure, Radiation and Temperature, Chapman Hall, London (1960), p. 304. 

Gaydon, A. G., Wolfhard, H. G., Flame, Their Structure, Radiation, and Tempera-... 

Wardman P, Dennis MF, Everett SA, Patel KB, Stratford MRL, Tracy M (2003) Radicals from one-electron reduction of nitro compounds, aromatic N-oxides and quinones the kinetic basis for hypoxia-selective, bioreductive drugs. Biochem Soc Symp 61 171-194 Warman JM, de Haas MP, Hummel A, van Lith D, VerberneJB, Loman H (1980) A pulse radiolysis conductivity study of frozen aqueous solutions of DNA. Int J Radiat Biol 38 459-459 Warman JM, de Haas MP, Rupprecht A (1996) DNA a molecular wire Chem Phys Lett 249 319-322 Warters RL, Lyons BW (1992) Variation in radiation-induced formation of DNA double-strand breaks as a function of chromatin structure. Radiat Res 130 309-318 Warters RL, Hofer KG, Harris CR, Smith JM (1977) Radionuclide toxicity in cultured mammalian cells Elucidation of the primary site of radiation damage. Curr Top Radiat Res Q 12 389-407 Weiland B, Huttermann J (1998) Free radicals from X-irradiated, dry and hydrated lyophilized DNA as studies by electron spin resonance spectroscopy analysis of spectral components between 77 K and room temperature. Int J Radiat Biol 74 341-358 Weinfeld M, Soderlind K-JM (1991) 32P-Postlabeling detection of radiation-induced DNA-damage identification and estimation of thymine glycols and phosphoglycolate termini. Biochemistry 30 1091-1097... 

Another form of iron disulphide occurs in nature as the mineral marcasitef which possesses a radiated structure and is frequently found as irregular balls on ehalky downs. When broken open the fracture exhibits a fibrous crystalline structure radiating from the centre—whence the name radiated pyrites. The fresh fracture is almost white m colour, and if quite pure the marcasite would probably be quite tin-white in appearance.7 When pure, its density at 25° C. is... 

Conductivity measurements on irradiated solids (2, 4, 5) revealed the similarity of the mechanisms of photo- and radiation-induced conductivity and indicated the importance of the role of traps and recombination centers which may exist at positions of disorder in the liquid or solid structure. Radiation-produced impurities can also act as traps. 

To complete the third-order calculation, we evaluate the tiny corrections from structural-radiation [40]... 

Rager T. Structured radiation-grafted polymer films and membranes. J Appl Polym Sci... 

Takashika, K., Oshima, A., Kuramoto, M., Seguchi, T., Tabata, Y, 1999. Temperature effects on radiation induced phenomena in polystyrene having atactic and syndiotactic structures. Radiat. Phys. Chem. 55 399 3. 

Yoksan, R., Akashi, M., Miyata, M., Chirachanchai, S. Optimal gamma-ray dose and irradiation conditions for producing low-molecular-weight chitosan that retains its chemical structure. Radiat. Res. 161, 471-480 (2004)... 

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