Irradiation of grain

Some 40 countries have cleared irradiated foods of certain types for human consumption, or have given provisional clearance. Large scale ( 104 tons per year) irradiation of potatoes has been approved in Japan, and very large scale ( 105 tons per year) irradiation of grains has been reported from the former Soviet Union for insect control. However, it must be admitted that clearances with associated legal complications have come slowly in most countries, and even today there are ongoing debates regarding the ethics and economics of food irradiation. 

Over the last few decades, the use of radiation sources for industrial applications has been widespread. The areas of radiation applications are as follows (i) Wires and cables (ii) heat shrinkable tubes and films (iii) polymeric foam (iv) coating on wooden panels (v) coating on thin film-video/audio tapes (vi) printing and lithography (vii) degradation of polymers (viii) irradiation of diamonds (ix) vulcanization of mbber and rubber latex (x) grain irradiation. 

Steinfeld et al. [133] demonstrated the technical feasibility of solar decomposition of methane using a reactor with a fluidized bed of catalyst particulates. Experimentation was conducted at the Paul Scherrer Institute (PSI, Switzerland) solar furnace delivering up to 15 kW with a peak concentration ratio of 3500 sun. A quartz reactor (diameter 2 cm) with a fluidized bed of Ni (90%)/Al2O3 catalyst and alumina grains was positioned in the focus of the solar furnace. The direct irradiation of the catalyst provided effective heat transfer to the reaction zone. The temperature was maintained below 577°C to prevent rapid deactivation of the catalyst. The outlet gas composition corresponded to 40% conversion of methane to H2 in a single pass. Concentrated solar radiation was used as a source of high-temperature process heat for the production of hydrogen and filamentous... 

Soviet Union, where an electron irradiation plant to treat imported grains went into operation in 1980 at Port Odessa and some 400,000 tonnes/year of grain were successfully treated by two electron accelerators. This facility is not currently in use in the Ukraine, after the collapse of the Soviet Union. 

Insect infestation of grains results in an annual loss of 500 million dollars. Present methods of chemical control are relatively unsatisfactory. There can be no doubt but that radiation could do a more satisfactory job than the chemicals, since it can treat infestation both inside and outside the kernels. A complete economic and logistic evaluation of the problem has been formulated by Chamberlain (Cl). The original cost estimate was low by a factor of 1.78. This mistake was corrected in a later version of the paper. He shows that isotope radiation can compete with conventional treatment methods if the irradiator can be located in the terminal warehouse and a charge of 1 cent/bu. can be assessed for the deinfestation. 

Y. Komem, P. Petroff, and R.W. Balluffi. Direct observation of grain boundary dislocation climb in ion-irradiated gold bicrystals. Phil. Mag., 26 239-252, 1972. 

During irradiation of the emulsion (exposure) those silver halide grains which have absorbed some light have one or a few silver cations reduced to metallic silver. These form a latent image on the emulsion, so called because it cannot be seen by the human eye on account of the very low concentration of metallic silver atoms. At this stage the photochemical process itself is over, the next steps in the processing of the exposed emulsion being dark (thermal) chemical reactions. 

Sulfur sensitization does not change the number of latent image centers formed per grain for low irradiance of the mono-disperse fine-grain emulsions. Sulfur sensitivity centers cannot be deep enough to affect the chance establishment of a single stable latent subimage center. In coarse, polydisperse... 

Design, construction of mobile irradiator and grain products irradiator... 

Laboratory investigations confirm that crystalline silicates form in stellar outflows and in protoplanetary disks. In contrast, dust grains in the ISM are dominated by amorphous materials less than 2.2% of the grains are crystalline silicates (Kemper et al 2005). Laboratory simulations of the harsh interstellar radiation fields demonstrate that ion irradiation of crystalline silicates quickly leads to their amorphization (e.g. Jager et al. 2003 Brucato et al. 2004). 

One possible way of implantation by the solar wind into the solid grains which I discussed in my 1965 paper47) is by irradiation of a layer of loose grains on the surface of a planetary body. Such a layer would be continuously... 

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