Papers by Keyword: Electron Radiation

Abstract: Radiation sterilization is widely used to sterilize nonwoven SMS medical products. SMS materials have improved filtering and barrier properties, low bacteriopermeability and, due to these properties, are indispensable for medicine. They are used to make such important health care products as disposable surgical clothing and underwear. As a result of the research carried out, the effect of gamma and electron radiation, in the range of absorbed doses from 15 to 25 kGy, on the strength characteristics of nonwoven SMS materials based on polypropylene with a surface density of 35, 40, 50 g/cm² was studied. It has been established that the strength characteristics (tensile strength, tensile strength, and tear strength) of nonwoven materials decrease after exposure to ionizing radiation. The higher the density of the material, the more its characteristics decrease after radiation sterilization. It was also found that gamma radiation, due to its nature, has a stronger effect on nonwoven materials based on polypropylene, and leads to a stronger decrease in strength characteristics. In general, for products sterilized by ionizing radiation and made from SMS materials, it is important to control the strength characteristics, primarily, the tensile strength in the transverse direction of the web stuff.

Abstract: Using optical and atomic-force microscopy methods, it has been established that exposure to electron radiation causes a change in the supramolecular structure of polypropylene – in films obtained by recrystallization of irradiated polypropylene, spherulites have a less perfect shape than films obtained from unirradiated polypropylene. Also, the films obtained by recrystallization of irradiated polypropylene surface roughness is greater.

Abstract: Metal-oxide-semiconductor (MOS) structure is highly sensitive to SiO₂-Si interface. It will reflect parameters such as interface density and oxide layer charge expediently. For the sake of researching of radiation effect of MOS structure irradiated by electron, we adopted 0.8 MeV electron at dosage between 2×10¹³ cm^-2~1×10¹⁴ cm^-2 as radiation source respectively. We found that electron radiation will induce interface density at SiO₂-Si interface. According to comparison with C-V curve of MOS structure at high frequency and low frequency, we obtain that the experimental data of interface density is up to 10¹⁴(cm^-2eV^-1). In addition, we also obtain the relationship between the parameter and radiation dosage.

Abstract: Single crystalline zinc oxide (ZnO) nanorods have been grown on Si (100) substrates by a hydrothermal method at 65 °C. In order to show the habit of crystalline growth and applied these ZnO 1D to the electron radiation. The ZnO nanorods grown on Si (100) have been characterized in detail using X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The XRD studies revealed that the ZnO nanowires showed the wurtzite structure (hexagonal). The Secondary Electron SEM image showed different morphology of the ZnO nanorods as a function of the reagents concentration. These nanorods have uneven tops and showed an apparent screw growth pattern with a typical hexagonal facets structure on the (0001) surface. The spiral growth step morphology strongly suggests that screw dislocations can play a significant role in promoting the ZnO nanorods growth and that the screw dislocation is growing in the polar axis of the ZnO nanorods. The ZnO nanorods were irradiated with electron beam (30 kV) for 100 minutes. We observed that the one-dimensional (1-D) ZnO nanorods were resistant to the electron radiation. This finding is interesting because, we can use these 1-D ZnO nanorods to development materials which can be resistant to radiation.