A combination of a long exposure to ultraviolet (UV) radiation and the extraction of radiolysis and photolysis products from tracks makes it possible to create ion-selective membranes from polyethylene terephthalate (PET) films irradiated with heavy ions. These membranes exhibit high selectivity for singly charged cations and high transport characteristics in the electrodialysis mode. The aim of this study is to analyze the mechanisms of the transformation of latent tracks into a system of through pores of the subnanometer range in more detail. Polyethylene terephthalate films are irradiated with accelerated Xe and Bi ions with energy losses in the polymer of 11 and 18 keV/nm, respectively. The evolution of the free volume and the accumulation of carboxyl groups in the irradiated films at different stages of the treatment are studied using gravimetry, IR and UV spectroscopy, conductometry, and electron microscopy methods. It is found that the properties of the resulting membranes depend on several critical parameters, which include, in addition to temperature during extraction, the energy loss of the bombarding ion, the pH of the solution used for extraction, and ion fluence. Dramatic changes in the membrane properties are observed at ion fluences at which individual tracks begin to overlap.

No abstract

The complex based on the DC60 cyclotron is intended for applied and fundamental research using beams of accelerated ions from carbon to xenon with energies from 0.34 to 1.77 MeV/nucleon, as well as for experiments on the channel of low-energy ion beams received from an ECR source with extraction intensities of up to 25 kV.On the DC60 cyclotron the accelerated ions energy variation is carried out through changing the ion charge, a possibility of smooth variation of ion energy by ±30% of the nominal value by means of changing the cyclotron magneticˇeld is also envisaged.Within the framework of commissioning the DC60 cyclotron, a number of experiments have been carried out on accelerating charged particle beams in the main points of the working diagram:• Investigation of acceleration modes for ions of nitrogen, argon, krypton ( • Investigation of possibilities for bunching the beam with a buncher and of the in uence of injected beam intensity on the acceleration efˇciency.• A beam has been extracted from the accelerator with an efˇciency exceeding 60%.• Accelerated ion beam of krypton ( 84 Kr 12+ ) with a current of up to 2 μA was extracted into a beam transport channel, shaped and transported to a technological facility for polymerˇlm irradiation. There has been shaped the irradiationˇeld with a required particle ux density and homogeneity, and experimental irradiation of polymerˇlm has been carried out.• Investigation of the modes of operational correction of the magneticˇeld with radial correcting coils of the cyclotron. • μ±μ³ ¤μ 2 ³± ¢Ò¢¥¤¥´¢¨μ´´μ-μ ¶É¨Î¥¸±¨°± ´ ²,¸Ëμ·³¨·μ¢ ´¨ ¶·μ¢¥¤¥´¤μ ɥ̴μ²μ£¨Î¥¸±μ°Ê¸É ´μ¢±¨ ¶μ μ¡²ÊÎ¥´¨Õ ¶μ²¨³¥·´μ° ¶²¥´±¨. 'Ëμ·³¨·μ¢ ´μ ¶μ²¥ μ¡²ÊÎ¥´¨Ö¸É·¥¡Ê¥³μ° ¶²μÉ´μ¸ÉÓÕ ¶μÉμ± Î ¸É¨Í¨μ¤´μ·μ¤´μ¸ÉÓÕ,¨ ¶·μ¢¥-¤¥´μ Ô±¸ ¶¥·¨³¥´É ²Ó´μ¥ μ¡²ÊÎ¥´¨¥ ¶μ²¨³¥·´μ° ¶²¥´±¨; DC60 Heavy Ion Cyclotron Complex: First Beams and Project Parameters•¨¸¸²¥¤μ¢ ´Ò ·¥¦¨³Ò μ ¶¥· ɨ¢´μ°±μ··¥±Í¨¨³ £´¨É´μ£μ ¶μ²Ö · ¤¨ ²Ó´Ò³¨± ÉÊϱ ³Í¨± ²μÉ·μ´ .

Existing technical means for loading silos with grain material do not fully meet the needs of production. The issue related to grain injury remains urgent, which predetermines the need to design a gravitational loader of another principle of operation with the appropriate theoretical justification for the movement of grain material in it. This paper has presented and substantiated the model of the gravitational movement of grain in the peripheral open screw channel with two variable angles of inclination. The model is based on the system of forces in the cylindrical coordinate system, acting on the volume of grain flow in the peripheral screw channel. The grain speed at the end of the braking section of the channel should be as low as possible but not less than the initial flow rate at the beginning of the acceleration section. The model takes into consideration this condition and ensures the optimal passage of grain along any part of the channel. The reported model makes it possible to obtain the speed of grain movement at any time, takes into consideration the height of the bunker hole and the dependence between the angles of inclination of the spirals of acceleration and brake sections. A mathematical dependence is given for these angles that ensures the passage of grain without its discharge and, at the same time, prevents injury to the grain mass due to a controlled decrease in the resulting speed. A separate dependence is provided to find the time at which the grain increases its speed on the acceleration section, reaching the maximum value. Based on the model, a peripheral open screw channel with two angles of inclination of spirals α and β has been proposed. For this channel, the relationships between its key parameters have been established, in particular, values have been substantiated for the recommended angles of 41°…45° for the acceleration section and 39°…35° for the brake section, respectively, as well as the hо/r ratio not less than 0.6...0.7.

No abstract