Техніка та технологія дезінтеграції й гравітаційного збагачення рідкіснометалічних руд

On the base of the analysis of centrifugal concentrators designs there has been justified the selection of apparatus for the rare-metal ores beneficiation. Process of pyrochlore ore grinding in mills of different types has been investigated and the expediency of use of impact centrifugal action mills to ensure selectivity of minerals disclosure has been founded. Efficient technical and technological parameters of the centrifugal action mills have been justified on the base of active experimental method. The influence of disintegration methods on technological indication of rare-metal ore beneficiation of Mazurovske deposits in centrifugal Nelson concentrator has been analyzed.На основі аналізу конструкцій відцентрових концентраторів обґрунтовано вибір апарату для збагачення рідкіснометалічних руд. Виконано дослідження процесу подрібнення пірохлорової руди в млинах різного типу та встановлено доцільність застосування млинів ударно-відцентової дії для забезпечення селективності розкриття мінералів. Методом активного експерименту обґрунтовано раціональні технічні та технологічні параметри млина ударно-відцентрової дії. Проаналізовано вплив способів дезінтеграції на технологічні показники збагачення рідкіснометалевої руди Мазурівського родовища у відцентровому концентраторі Нельсона

Mediators of mechanotransduction between bone cells

Mechanical forces are known to regulate the function of tissues in the body, including bone. Bone adapts to its mechanical environment by altering its shape and increasing its size in response to increases in mechanical load associated with exercise, and by decreasing its size in response to decreases in mechanical load associated with microgravity or prolonged bed rest. Changes in bone size and shape are produced by a cooperative action of two main types of the bone cells - osteoclasts that destroy bone and osteoblasts that build bone. These cell types come from different developmental origins, and vary greatly in their characteristics, such as size, shape, and expression of receptor subtypes, which potentially may affect their responses to mechanical stimuli. The objective of this study is to compare the responses of osteoclasts and osteoblasts to mechanical stimulation. This study has allowed us to conclude the following: 1. A mediator is released from a single source cell. 2. The response to the mediator changes with distance. 3. The value of the apparent diffusion coeficient increases with distance. 4. A plausible proposed mechanism is that ATP is released and degrades to ADP. 5. Future experiments are required to confim that ATP is the mediator as suggested

The earliest spectroscopy of the GRB 030329 afterglow with 6-m telescope

The earliest BTA (SAO RAS 6-m telescope) spectroscopic observations of the GRB 030329 optical transient (OT) are presented, which almost coincide in time with the "first break" ($t\sim 0.5$ day after the GRB) of the OT light curve. The beginning of spectral changes are seen as early as $\sim 10-12$ hours after the GRB. So, the onset of the spectral changes for $t<1$ day indicates that the contribution from Type Ic supernova (SN) into the OT optical flux can be detected earlier. The properties of early spectra of GRB 030329/SN 2003dh can be consistent with a shock moving into a stellar wind formed from the pre-SN. Such a behavior (similar to that near the UV shock breakout in SNe) can be explained by the existence of a dense matter in the immediate surroundings of massive stellar GRB/SN progenitor). The urgency is emphasized of observation of early GRB/SN spectra for solving a question that is essential for understanding GRB physical mechanism: {\it Do all} long-duration gamma-ray bursts are caused by (or physically connected to) {\it ordinary} core-collapse supernovae? If clear association of normal/ordinary core-collapse SNe (SN Ib/c, and others SN types) and GRBs would be revealed in numbers of cases, we may have strong observational limits for gamma-ray beaming and for real energetics of the GRB sources.Comment: 4 pages, 5 figures. Proceedings of the 4th Workshop "Gamma-Ray Bursts in the Afterglow Era", Roma, 2004 October 18-22, eds. L. Piro, L. Amati, S. Covino, and B. Gendre. Il Nuovo Cimento, in pres

Formation of Digital Literacy of Undergraduate Students in the Context of Sustainable Development Goals

The paper aims to develop a model of a training course aimed at forming undergraduate students’ digital literacy, considering the goals of sustainable development and the implementation of a competency-based approach. The tasks were to analyze digital literacy frameworks in the context of sustainable development goals, analysis of educational standards of higher education at the bachelor’s level, and modeling on this basis the content of the academic discipline, determining the methodological conditions of the learning process, and choosing instrumental solutions for designing the course and implementing academic discipline. In the process of identifying and analyzing the existing framework of digital competencies, international frameworks, and practical experience, we proposed a way to correlate these models with the tasks of implementing a competency-based approach and adapting these models to the national conditions for the implementation of educational programs at the higher education level. We developed a scientific concept and modeled the “Digital Culture” training course, aimed at developing digital literacy of students in all areas of training at the bachelor’s level

Problems and prospects of development of ecological tourism in Ireland

The paper presents the research on the development of ecological tourism in Ireland. The basic directions and problems of development of ecotourism. Income from ecotourism in the country was analyzed in the article, as well as the model for the attraction of tourists to Irelan