Restoration of soils contaminated with radionuclides by phytoredomediation method

The possibility of soil restoration by means of phytotechnology and artificial geochemical barriers (GB) from contamination by radionuclides (RN) and toxic elements (TE) is methodologically substantiated. For this purpose, a number of artificial GBs were created at a special landfill within the framework of a model experiment. The process of formation and development of barriers, their parameters are investigated. Agrophytocenosis cultures were selected for optimal phytostabilization of soil conditions. The study of phytoextraction of TE and RN by agrophytocenosis cultures during one complete vegetation period was performed. Some selectivity of the investigated plants for extraction of different TEs and RNs from soils and material of barriers was revealed.Методологічно обґрунтована можливість відновлення стану ґрунтів за допомогою фітотехнологій та штучних геохімічних бар'єрів (ГБ) від забруднення радіонуклідами (РН) і токсичними елементами (ТЕ). Для цього створено ряд штучних ГБ на спеціальному полігоні в рамках модельного експерименту. Досліджено процес формування та розвитку бар'єрів, визначені їх параметри. Вибрано культури агрофітоценозів для оптимальних варіантів фітостабілізації стану ґрунтів. Виконано дослідження фітовилучення токсичих елементів (ТЕ) і РН культурами агрофітоценозів протягом одного повного вегетаційного періоду. Виявлена певна селективність досліджуваних рослин щодо вилучення різних ТЕ і РН з ґрунтів і матеріалу бар'єрів.Методологически обоснована возможность восстановления состояния почв с помощью фитотехнологий и искусственных геохимических барьеров (ГБ) от загрязнения радионуклидами (РН) и токсичными элементами (ТЭ). Для этого создан ряд искусственных ГБ на специальном полигоне в рамках модельного эксперимента. Исследован процесс формирования и развития барьеров, определены их параметры. Выбраны культуры агрофитоценозов для оптимальных вариантов фитостабилизации состояния почв. Выполнены исследования фитоизвлечения ТЭ и РН культурами агрофитоценозов в течение одного полного вегетационного периода. Выявлена определенная селективность исследуемых растений по изъятию различных ТЭ и РН из почвы и материала барьеров

The researches of kinetic electron emission for creation of new-type current source

It is suggested that the high energy electrons produced in ionization due to the nuclear particle flow should be used for effective conversion the radioactive decay energy into electrical energy. The conversation of secondary electron emission energy enables one to create a power source with a typical voltage of (10-20) V and a capacity above 2000 KWt×h/kg, this being much higher than for common sources. Moreover, the operation of this type of sources does not require heating to high temperature and use of a refrigerator; this significantly extends their area of application. The experimental studies into secondary emission characteristics of various materials were carried out to optimize binary cell materials of a secondary - emission radioisotope current source. The total current as a function of collector materials was measured. New data on the secondary emission characteristics of certain materials were obtained. It was ascertained that the total binary cell current had an effect upon secondary electron - electron emission. By way of example, a typical power dependence of voltage was investigated for copper collector; the optimum voltage value corresponding to peak power was calculated too

Magnetic levitational bioassembly of 3D tissue construct in space

Magnetic levitational bioassembly of three-dimensional (3D) tissue constructs represents a rapidly emerging scaffold- and label-free approach and alternative conceptual advance in tissue engineering. The magnetic bioassembler has been designed, developed, and certified for life space research. To the best of our knowledge, 3D tissue constructs have been biofabricated for the first time in space under microgravity from tissue spheroids consisting of human chondrocytes. Bioassembly and sequential tissue spheroid fusion presented a good agreement with developed predictive mathematical models and computer simulations. Tissue constructs demonstrated good viability and advanced stages of tissue spheroid fusion process. Thus, our data strongly suggest that scaffold-free formative biofabrication using magnetic fields is a feasible alternative to traditional scaffold-based approaches, hinting a new perspective avenue of research that could significantly advance tissue engineering. Magnetic levitational bioassembly in space can also advance space life science and space regenerative medicine. Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY)