Improving Safety of Shielding Chambers Equipped with Viewing Windows

The article describes and proves the possibility of increasing the protection against neutron radiation for personnel by means of immersion liquid without major changes in the design of the equipment used and without reducing the safety of the radiation object. Studies of the components properties of the protection glass and the immersion liquid have shown that the properties of the immersion liquid reduce the dose rate of neutron radiation significantly compared to the protection glass, which is used for the main protection against ionizing radiation when working with uranium-plutonium fuels. The use of two-layer protection in viewing windows allows reducing the dose rate of mixed gamma-neutron radiation to values that do not exceed the safe radiation dose for personnel when working with an ionizing radiation source, which in this case is 50 kg of uranium-plutonium fuel

Мониторинг процесса иммерсионного оптического просветления коллагеновых волокон с помощью оптической когерентной томографии

Future development of the method of immersion optical clearing of biological tissues—this method is widely used in the study of the morphology and pathologies of tissues in vitro and considered promising for in vivo applications in biophysical research and medicine—requires knowledge of the details of interaction of immersion liquids with the tissue, in particular, the characteristics both of the tissue dehydration process, which is caused by the osmotic effect of the immersion liquid, and the process of diffusion of the immersion agent (IA) into the tissue. The optical properties of skin dermis, eye sclera, tendon, and many other tissues are determined by the properties of collagen bundles, abundant in these tissues. In the present work, a convenient and reliable technique for monitoring the optical properties and geometry of collagen bundles in the course of their immersion clearing in vitro, based on optical coherence tomography (OCT), is proposed. The main advantage of this technique is that it allows one to monitor changes in the geometric and optical properties of the tissue simultaneously, without interrupting the natural course of the immersion clearing process, and to obtain reliable estimates of the characteristic times and rates of both the process of tissue dehydration and process of diffusion of the IA into the tissue.

Image Information Obtained Using a Charge-Coupled Device (CCD) Camera During an Immersion Liquid Evaporation Process for Measuring the Refractive Index of Solid Particles

The refractive index is a fundamental physical property of a medium, which can be used for the identification and purity issues of all media. Here we describe a refractive index measurement technique to determine simultaneously the refractive index of different solid particles by monitoring the transmittance of light from a suspension using a charge-coupled device (CCD) camera. An important feature of the measurement is the liquid evaporation process for the refractive index matching of the solid particle and the immersion liquid; this was realized by using a pair of volatile and non-volatile immersion liquids. In this study, refractive indices of calcium fluoride (CaF2) and barium fluoride (BaF2) were determined using the proposed method.