Gamma-irradiated control

Kamat, A. et al.. Potential application of low dose gamma irradiation to improve the microbiological safety of fresh coriander leaves. Food Control, 14, 529, 2003. 

The two-step process of epitaxial polymerization has been applied to symmetrically substituted diacetylenes First, the monomers have been crystallized epitaxially on alkali halides substrates from solution and the vapor phase. The oriented monomer crystals are then polymerized under the substrate s influence by gamma-irradiation. The diacetylenes in this study are 2,4-hexadiyn-l,6-diol (HD) and the bis-phenylurethane of 5,7-dodecadiyn-l,12-diol (TCDU). The polydiacetylene crystal structures and morphologies have been examined with the electron microscope. Reactivity and polymorphism are found to be controlled by the substrate. 

After washing and draining, the oysters were packed in 1-pint cans, placed in Arctic hampers, covered with ice, and transported to the LSU Nuclear Science Center. Here, they were divided in half one part served as the nonirradiated control, and the other part was subjected to gamma irradiation doses ranging from 0.2 to 0.3 Mrad. The irradiation was performed within 24 hours after the oysters came from the beds. After irradiation, both the irradiated and the nonirradiated controls were stored in crushed ice, which w s added as needed. 

Montanari L, Cilurzo F, Valvo L, et al. Gamma irradiation effects on stabibty of poly(lactide-co-glycolide) microspheres containing clonazepam. J Control Release 2001 75(3) 317-330. 

Bittner B, Mader K, KroU C, et al. Tetracycline-HCl-loaded poly(DL-lactide-co-glycolide) microspheres prepared by a spray drying technique influence of gamma-irradiation on radical formation and polymer degradation. J Control Release 1999 59(l) 23-32. 

Cornwell, P.B. and Bull, J.O. (1960) Insect control by gamma irradiation an appraisal of the potentialities and problems involved. Journal of the Science of Food and Agriculture, 11, 754-758. 

Gamma irradiation The isotope Co is used as radiation source. A typical dose rate is 2 kGy/h. The dose is controlled by the exposure time and measured with a dosimeter. 

Oosimetry Dose delivery in industrial-scale cobalt-60 gamma irradiators is achieved through controlling the time of exposure of the product to the source. The initial relationship between source strength, product bulk density, time of exposure, and absorbed dose has to be determined empirically by dosimetry. 

Figure 9. Calibration curve (A) of PSII particles from Spinacea oleracea exposed to gamma r ( Cs dose rate 1.2mGy/h)and(B) fast neutrons (dose rate 1.26 mGy/h)-JRC,Ispra, (IT). The temperature and pH were highly controlled. Ai/Ac ratio of area irradiated /control...

The size-controlled synthesis of octahedral cuprous oxide nanocrystals via gamma irradiation of water-in-oil emulsions consisting of Triton X-100, -hexanol, and cyclohexane with added solution of copper(II) nitrate was performed (He et al. 2005). The resulting mixtures were stirred mildly at RT until they became transparent. Before they were irradiated, the microemulsions were ultrasoni-cated for 10 min, and bubbled with pure nitrogen for 30 min to remove oxygen. 

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