Thermotunnel refrigerator with vacuum/insulator tunnel barrier: A theoretical analysis

The authors use two insulator layers in thermotunnel refrigerator to modify the shape of the tunneling barrier so that electrons with high kinetic energy pass it with increased probability. Theoretical analysis show that the overall tunneling current between the electrodes contains an increased number of high kinetic energy electrons and a reduced number of low energy ones, leading to high efficiency. The particular case of vacuum gap and solid insulator layer is calculated using digital methods. Efficiency remains high in the wide range of the emitter electric field. The cooling coefficient is found to be as high as 40%-50% in the wide range of the emitter electric field.Comment: 9 pages, 3 figure

Stable dynamics in forced systems with sufficiently high/low forcing frequency

We consider a class of parametrically forced Hamiltonian systems with one-and-a-half degrees of freedom and study the stability of the dynamics when the frequency of the forcing is relatively high or low. We show that, provided the frequency of the forcing is sufficiently high, KAM theorem may be applied even when the forcing amplitude is far away from the perturbation regime. A similar result is obtained for sufficiently low frequency forcing, but in that case we need the amplitude of the forcing to be not too large; however we are still able to consider amplitudes of the forcing which are outside of the perturbation regime. Our results are illustrated by means of numerical simulations for the system of a forced cubic oscillator. In addition, we find numerically that the dynamics are stable even when the forcing amplitude is very large (beyond the range of validity of the analytical results), provided the frequency of the forcing is taken correspondingly low.Comment: 12 pages, 3 figures, 2 table

Scenario analysis report with policy recommendations: An assessment of sustainability, resilience, efficiency and fairness and effective chain relationships in VALUMICS case studies : Deliverable 8.4

This is an open access article distributed under the Creative Commons Attribution License, to view a copy of the license, see: https://creativecommons.org/licenses/by/4.0/. The final version of this report is available at https://doi.org/10.5281/zenodo.6534011The functioning of food value chains entails a complex organisation from farm to fork which is characterised by various governance forms and externalities which have shaped the overall food system. VALUMICS food value chain case studies: wheat to bread, dairy cows to milk, beef cattle to steak, farmed salmon to fillets and tomato to processed tomato were selected to enable explorative and empirical analysis to better understand the functioning of the food system and, to identify the main challenges that need to be addressed to improve sustainability, integrity, resilience, and fairness of European food chains. The VALUMICS system analysis was executed through four operational phases starting with Groundwork & analysis including mapping specific attributes and impacts of food value chains and their externalities. This was followed by Case study baseline analysis, which provided input to the third phase on Modelling and exploration of future scenarios and finally Policy and synthesis of the overall work. This report is an overall synthesis of the VALUMICS results as follows: • Key findings from the VALUMICS project on the functioning of European food value chains and their impacts on more sustainable, resilient, fairer, and transparent food system are summarised through a compilation of 25 Research Findings and Policy Briefs. • By highlighting the major contributions from the research activities throughout the four phases of the VALUMICS project, this report delivers an assessment of various factors influencing sustainability, resilience, efficiency and fairness and effective chain relationships of different food value chains, and their determinants. • The synthesis of the outcome allows the identification of opportunities and challenges characterising the functioning of food supply chains, and thus, the prospects and potentials for strengthening the EU food sector

Public political narratives: developing a neglected source through the exploratory case of Russia in the Putin-Medvedev era

The place of narrative in political science is an issue that resurfaces with regularity, usually focusing on the questions of generalisability, evidence and causality which lie at the heart of the discipline. Most such debate concerns the use of narrative by political scientists. Far less attention has been devoted to the use of narrative by political actors, despite its relative ubiquity. Even where such attention has been given, it concentrates less on the narrative per se, and more on its performance and impact. However, the nature of public political narratives means that analysis of them facilitates a holistic understanding of their narrators' politics. A public political narrative consists of a sequential account given by political actors connecting selected, specific developments so as to impose a desired order on them. Taking contemporary Russia as an exploratory case, narrative analysis draws out the motivations, world view and inconsistencies within the Putin-Medvedev regime. Recurring motifs and symbols identify the regime's political priorities, explaining policy choices and revealing future concerns. Narrative has a predictive aspect, identifying likely policy responses to unexpected events. Narratives capture time, and shifts in their temporalities indicate changes in self-conceptualisation and political priorities. Temporal appropriations include or exclude particular agential and causal explanations. The relationship between their plots and subplots represents a political signalling process. Public political narratives provide temporally and spatially specific exceptionalist accounts, but their combinatory quality also facilitates comparative analysis. The approach essayed here provides methodological generalisability, arguing that the neglect of public political narratives merits correcting

Crystal, electronic structure and physical properties of U₃Rh₄Ge₁₃ and Th₂Rh₃Ge₅

Crystal structures of U3Rh4Ge13 [structure type HT-Y3Pt4Ge13, space group R3c, a = 5.6004(6) Å, c = 15.5158(1) Å, RB = 0.022, Rp = 0.021] and of Th2Rh3Ge5 [structure type U2Co3Si5, space group Ibam, a = 10.0572(1) Å, b = 11.9142(1) Å, c = 6.0997(1) Å, RB = 0.027, RP = 0.037] are refined by powder X-ray diffraction method. Their structural relationships with primitive cubic Yb3Rh4Sn13 and body-centered tetragonal ThCr2Si2 types, respectively are discussed. The ac and dc magnetic susceptibility measurements on U3Rh4Ge13 revealed an antiferromagnetic ordering at TN = 22 K followed by a metamagnetic transition below 5 K. The magnetic entropy Smag ≈ Rln4 at TN indicates U3Rh4Ge13 to follow the classical LS coupling scheme. This finding together with the performed theoretical DFT calculations hint toward localized nature of 5f states in the studied germanide. U3Rh4Ge13 reveals metallic transport properties, low thermal conductivity (i.e. 0.4–0.6 W m−1 K−1) as well as displays a structural phase transition in the temperature range of 292–315 K. Electrical resistivity measurements and theoretical DFT calculations indicated Th2Rh3Ge5 to be a simple metal. © 2022 Elsevier B.V

Influence of western Siberian artesian basin’s groundwater on migration of macro and microelements in small streams

В статье приводятся особенности макро- и микроэлементного состава артезианских вод Тобольского района, фонтанирующих из геологоразведочной скважины № 36-РГ и дальнейшей миграции химических элементов в малой реке Аремзянка в результате впадения ручья артезианской воды. Выявлено, что миграция Cl, Br, B, Se, Na, As, Sr, Ba, Te более интенсивна в артезианских водах, в то же время Ca, Mg, Al, Si, P, S, Mn, U сильнее мигрируют в фоновых речных водах. Показано, что в результате впадения в реку ручья артезианской воды, ниже по течению происходит увеличение подвижности наиболее интенсивных мигрантов кислородных вод – Cl, Br, B, Na, Sr, F и среднеинтенсивного мигранта Ba. Подвижность основных макроэлементов речных вод – Ca и Mg – наоборот, несколько уменьшается вследствие изменения ионного состава воды. Увеличения подвижности других макро- и микроэлементов не выявлено.The article presents the features of macro and trace element composition of artesian waters, leaking from exploration drilling well № 36-RG in Tobolsk area, and further migration of chemical elements in the waters of small river Aremzyanka due to inflow of artesian water stream. Revealed that the migration of Cl, Br, B, Se, Na, As, Sr, Ba, Te is more intensive in artesian waters, while Ca, Mg, Al, Si, P, S, Mn, U stronger migrate in background river waters. Found that as a consequence of the artesian water inflow migration intensity of the most intensive in oxygen waters migrants like Cl, Br, B, F, Na, Sr and medium intensity migrant Ba in the river downstream Aremzyanka enhances. On the contrary, migration mobility of the major macroelements of the river water – Ca and Mg – somewhat reduced due to changes in the ionic composition of the water. Migration mobility increase for other macro and microelements in the stream was not revealed