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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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The paper looks at recent research dealing with small angle X-ray scattering. It is shown that this is the result of the interaction of X-ray radiation with the electrons of the sample nanoparticles. It is said that measurements were taken on a Rigaku Rotaflex D/MAX-RC X-ray unit. Small-angle scattering experiment was carried out using the Kratky attachment. The Kratky attachment served as an adjustment. Of particular interest and importance is that a unique sample, zeolite ZSM-5, was taken for the study. Zeolites are crystalline substances with developed porosity, and data by X-ray diffraction analysis can be used for determining the structural features of catalytically active centers. It is worth saying that it is necessary to elucidate the reaction mechanisms. At first it was decided to get a wide-angle X-ray pattern for determining the degree of crystallinity. There were the results of lowtemperature nitrogen sorption measurements, which also allowed to estimate the degree of crystallinity. Experimental X-ray patterns were processed in the Jade program. We were convinced that samples were zeolite ZSM-5 and drew relevant conclusions about the degree of crystallinity by measuring peak aries on the X-ray patterns. The obtained values of crystallinity were close to those that we received earlier by low-temperature nitrogen sorption, thus we were convinced that the method is valid. To measure pore sizes in zeolites, it is necessary to use the small-angle attachment to X-ray source. The air was pumped out from the chamber and its scattering was registered in a range from 0,3 to 8 degrees by 2Θ. It should be mentioned that the processing of the experiments data obtained on the low-angle attachment was carried out in the PrimusQT program and manually in the OriginPro program guided following the Guinier method. The resulting values of crystallinity are comparable. Based on the results obtained, we can see a possible relationship between pore sizes and crystallinity of zeolites ZSM-5. The higher the degree of crystallinity the smaller the size of the mesopores. In addition, it is stressed that this research is interdisciplinary and therefore it requires hard work and cooperation between physicists, biologists and chemical engineers.