جستجوی مقالات مرتبط با کلیدواژه « Ultraviolet » در نشریات گروه « مهندسی شیمی، نفت و پلیمر »

Today, due to the use of eggs as a complete food package, directly and indirectly, it is important to maintain quality. In this study, fresh eggs purchased and after placing the samples under UV rays with different levels of parameters, they were divided into two groups of impregnated and not impregnated sunflower oil. The samples were then stored for two days and then, the biochemical properties were determined for them including the percentage of fat and crude protein, pH and total ash. In the statistical analysis, the results for pure fat were the highest and the lowest was 48.3333 (20 lamps- 3 hours irradiation time) and 33.3333 (60 lamps- 1 hour irradiation time). In the study of the effects of the number of lamps and UV irradiation time on total ash, no significant changes were made at different levels of the parameters. There were also significant changes in the number of LED lamps and irradiation times in the raw protein review so that the highest level of protein in the parameters studied in this section was 40 lamps and 1 hour of irradiation and the lowest level The protein was about 20 lamps and 2 hours of ultraviolet radiation. In the pH check, the increase in the number of ultraviolet lamps and irradiation time reduced the amount of pH; As a result of the inverse relationship between the increase in the number of LED lamps and the irradiation time with the pH value. Also performing impregnated eggshell sunflower oil was a decrease in pH value.

Hypothesis:

 In recent years, some modern techniques such as plasma, ultraviolet irradiation and ozone treatment have been used in surface modification of polymers. Surface modification of polymeric fibers is aimed to improve dying and to achieve desirable physical properties like high moisture absorption and lower anti-static. In this study in an attempt to modify the surface of polyester fibers, a new complex method through ultraviolet/ozone treatment in two wet and dry forms has been applied.

Surface modification of polyester fibers was performed by ultraviolet/ozone treatment on dry samples, as well as on samples impregnated with water, hydrogen peroxide and hydrogen peroxide/sodium silicate solutions. In order to study and compare the functional groups and morphology of the polyester fibers with those of control sample, Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used. Also, the moisture absorption and static electricity of the samples were studied.

The results of FTIR spectra revealed that by ultraviolet/ozone treatment the number of oxygen-containing functional groups has increased considerably. Also, nanoscale surface roughness of the treated samples was revealed by SEM images. Additionally, the results indicated that moisture absorption of the treated polyester fibers has risen and consequently their static electricity has decreased. According to the results, the impregnation of polyester fibers can remarkably enhance surface oxidation process.