Gamma-radiation applications

Shahriary L, Ghourchain H, Athawale AA. Grapbene-multiwalled carbon nanotube hybrids synthesized by gamma radiations application as a glucose sensor. J Nanotechnol 2014 903872 1-10. 

Table 3 lists the selected properties [16] that we have measured for several commercially available acrylate resins manufactured by the Sartomer Company and the Rohm and Haas Company. The resins were cured in an AECL Gammacell Model 240. The temperature rise was measured for an 8-g sample using Acsion s (formerly AECL Radiation Applications Branch) Gamma Calorimetry method [17]. All of this information is being used to evaluate the applicability of EB-cured acrylate adhesives for repairing composite structures. Combinations of these adhesives can be used to create electron-curable adhesives suitable for composite repair. 

The metal is radioactive and does not occur in nature, as the half-life of all isotopes is shorter than 5 million years. It is found in readily isol-able amounts in nuclear reactors. It is an effective "rust-preventer" for iron and steel in special applications. The metastable isotope "Tc has a half-life of only 6 hours and is therefore used as a gamma radiator in medicine (radiation therapy and diagnostics). Of very little commercial importance. 

Sivinski, J. and B. Smittle. 1990. Effects of gamma radiation on the development of the Caribbean fruit fly (Anastrepha suspensa) and the subsequent development of its parasite Diachasmimorpha longicaudata. Entomolog. Exper. Applic. 55 295-297. 

Although the devices outlined above are the most commonly used for evaluating total alpha, beta, and gamma radiation, other methods and other devices can be used. In addition, local conditions (i.e., temperature, humidity) or the properties of the specific radionuclides emitting the radiation may make other types of devices or other methods more optimal to achieve the goals of the survey than the devices noted above. There, experts or individual vendors should be consulted to determine the appropriate measurement device for any specific application. 

Closed-cell foams made from metallocene-based polyolefins (MPO) have potential for use in various applications because of their uniform composition and low toxicity. Compressive stress relaxation is used to investigate the behaviour of these foams. In particular, its behaviour is compared with open-cell PU foams, a material MPO foams could possibly replace. The effect of gamma radiation on MPO foam behaviour is also... 

Any material proposed for implantation, whether for cell transplantation or some other application, must be biocompatible i.e. it must not provoke an adverse response from the host s immune system. If this goal is not met the implant may be rejected. To this end it is important that the material be easily sterilized either by exposure to high temperatures, ethylene oxide vapor, or gamma radiation. A suitable material must therefore remain unaffected by one of these three techniques. However, biocompatibility is not simply a question of sterility. The chemistry, structure, and physical form of a material are all important factors which determine its biocompatibility. Although our understanding of the human immune system is advancing rapidly, it is not yet possible to predict the immune response to a new material. This can only be determined by in vivo experiments. 

PC—copolyester better processibility, hydrolytic, and gamma radiation resistance than PC sterilizable applications 43,109... 

Polysulfones also offer desirable properties for cookware applications, eg, microwave transparency and environmental resistance to most common detergents. Resistance to various sterilizing media (eg, steam, disinfectants, and gamma radiation) makes polysulfones the resin family of choice for many medical devices. Uses in the electrical and electronic industry include printed circuit boards, circuit breaker components, connectors, sockets, and business machine parts, to mention a few. The good clarity of PSF makes it attractive for food service and food processing uses. Examples of applications in this area include coffee decanters and automated dairy processing components. 

HPhe radiation preservation of fresh fruits and vegetables has received considerable attention as one of the promising applications for food irradiation. As with most other applied aspects of food irradiation, however, the process is not without complications. This paper is concerned only with the effect of gamma radiation upon fresh commodities, drawn principally from work conducted at this laboratory. No effort is made to cover all of the changes occurring but rather only a few which illustrate the problems or limit the practical application of the process. 

The use of ionizing radiation as a way to sterilize the environment and prevent oral transmission of this parasite also showed no practical application (Dias, 2006). The use of gamma rays on infected blood at an exposure of 5000 rad was not sufficient to inactivate the parasite, and studies with doses of 90 krad showed a loss of virulence, but not complete killing of the parasite (Amato Neto et al., 1996 Salata et al., 1973). Takeda et al. (1986) suggested that the gamma radiation dose to kill T. cruzi could be between 200 and 300 krad (Takeda et al., 1986). 

The radiation resistance of polyurethanes is better than that of other polymer materials and makes them a good candidate in applications where there is gamma radiation. 

In the present work, further mechanistic data for the acid effect in both UV and gamma radiation systems are reported, particularly molecular weight studies on the species present in the grafting solutions. The significance of these acid effects in possible commercial applications of the resulting copolymers of cellulose is also briefly mentioned. 

Another ion-exchange application of natural zeolites is the removal of radioactive ions from waste-water [7,17,18,20,57,70,71], Chabazite, clinoptilolite, and mordenite selectively exchange radioactive Cs+ and Sr2+ from solutions [5,7,17,18,20,57,70,71], In addition, the high temperature, because of the activity of these radionuclides, and the effect of gamma radiation do not affect the performance of natural zeolites, which is the case for organic ion-exchange resins [72],... 

Density gauges based on the absorption of gamma radiation are used wherever the automatic determination and control of the density of liquids, solids, or slurries is important. The oil industry relies heavily on such instmments. Other applications are in the handling of slurries in mineral processing or even in the food industry. One of the earliest users of radioisotope instmments was the tobacco industry, where density gauges make sure the right amount of tobacco is packed into each cigarette. 

Stock, D.A. Achey, P.M. Repair of single-strand breaks in DNA from cultured leptidopteran cells exposed to gamma radiation. In Invertebrate Cell System Applications Mitsuhashi, J., Ed. CRC Press, 1989 1, 45-61. 

Thulium-170, a radioactive isotope of thulium, has been used in portable X-ray machines for use in medical and dental procedures. This isotope gives off gamma radiation. Gamma radiation is very similar to X rays. They pass through soft tissues in the body like X rays. But they are blocked by bones and other thick materials. So a small amount of thulium-170 acts just like a tiny X-ray machine. It can be carried around more easily than can a big X-ray machine. Another radioactive isotope of thulium, thulium-171, may have some application as an energy source. 

Plutonium-238 produced from neutron-irradiated Np-237 is not isotopically pure usually, the material contains > 80 % Pu-238 and < 20 % of heavier Pu isotopes, and in addition a few ppm of Pu-236. While the presence of other Pu isotopes generally does not seriously affect the applicability of Pu-238 as a heat source, its use for medical applications (heart pacemakers etc.) is limited by Pu-236 because of the intense gamma radiation of some of the Pu-236 daughters. Pu-238 which is practically free from Pu-236 can be made by irradiation of Am-241, and alpha decay of the Cm-242 thus produced. There are in principal two ways for producing such materials... 

Mossbauer effect Resonance absorption of gamma radiation by specific nuclei arranged in a crystal lattice in such a way that the recoil momentum is shared by many atoms. It is the basis of a form of spectroscopy used for studying coordinated metal ions. The principal application in bioinorganic chemistry is 57Fe. The parameters derived from the Mossbauer spectrum (isomer shift, quadrupole splitting, and the hyperfine cou-... 

Membrane filtration application to biopharmaceutical product development is extremely important since sterile protein-peptide products can only be prepared via sterile filtration and gamma radiation steam cannot be used under pressure. There are several excellent works in the field of sterile membrane filtration.34-36 The filter media most often tested for protein formulations with minimum adsorption and maximum compatibility are mixed esters of cellulose acetate, cellulose nitrate, polysulfone, and nylon 66. Membrane filters must be tested for compatibility with the active drug substance and selected for formulations if they have the lowest adsorption and maximum compatibility with the product. 

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