A more advanced theoretical model of the sphere earth's EM in a foreign homogeneous EM field

Introduction/purpose: The paper describes a more advanced theoretical model of the Earth's EM field based on two-component hypotheses. A defined mathematical model that shows the rotation of the magnetically conducting sphere of Tthe magnetization M in a foreign magnetic field and the components of the magnetic field that may arise due to the rotation of the Earth around its axis. According to the established model, in relation to the reference values of the planet Earth, the values of the components of the other planets in the solar system were calculated and the results were tabulated. Methods: The solution to the problem highlighted in the title of the paper was determined using the combined, for that purpose, formalized methods of physics and mathematical analysis, in order to develop a new, more advanced mathematical model. For this purpose, the method of analogy was used, related to the application of similar structural forms and systems for researching electromagnetic processes and planetary rotation. The method of analogy was applied for two interrelated reasons. The first one is that all values that characterize the function of any natural system are subject to change, and the second one is that the applied solutions do not determine the conditions of the structure's function in each specific case. Results: The solutions in the form of original analytical formulas and numerical values arranged in Table 2, referring to the influence of the rotation of the planets and especially the Earth, will be applied to research the effects of the EM field emitted by the Sun towards the planets, especially the role that the process plays in protecting the planet Earth. The results given in Table 2 are particularly important. Conclusion: The paper discusses the appearance and effect of the Earth's EM field in a way that is understandable at the current level of scientific development. Scientific findings in science and measurements in geo- and astrophysics indicate the Sun as a possible source of the EM field that extends through interplanetary space and the component of the Earth's magnetic field is only a response to the influence of that source. Natural phenomena and processes on the Earth can be defined in system theory by a model that contains changes in the parameters of the state of the planet

Flexibility options to tackle intermittency in the energy systems with high share of renewable energy

Recent ”Green deal” of European union includes the decision to become carbon neutral and even carbon-negative region in order to tackle the climate crisis. Such decision includes energy transition from energy production based on fossil fuels to the system based on variable renewable energy sources. Main technical challenge and a key factor in the techno-economic analysis of the energy system of the future, based on variable renewable energy sources, is their variable production. In order to deal with this problem in long-term energy planning, different approaches have been tried, focusing on overcapacity, storage capacities and sectors coupling with heating and transport. In this research, different flexibility options, storage and demand response technologies are modelled on several levels of energy systems: national, regional and continental. With the case study area including all EU countries modelled in EnergyPLAN model, the goal of the research is to show how each flexibility option influences the production capacities of renewable energy source technologies, storage technologies and demand response in order to reach a certain share of renewable energy in final energy consumed. Climate differences were taken into account for modelling of the behaviour of flexibility options, which is shown to be relevant for the creation of their representative curves. Representative curves are created as functions of critical excess electricity produced and share of renewable energy integrated into the system. Results show representative curves of most relevant flexibility options for several regions of EU and for the whole EU as one region. These results are further discussed in terms of strategic decisions addressing the dynamics of integration of such technologies, i.e. deciding on the priority of their integration in the energy system of the region in consideration. Results of research can be applied for integrated assessment models, in long-term planning of energy transition towards carbon-negative energy systems

Characterization of Roman mortar from the Mediana archeological site

Ovaj rad prikazuje istraživanje rimske žbuke rabljene za konstrukciju poda u objektima koji su imali sustav podnog grijanja – hipokaust, u rezidencijalnim vilama s peristelom (Naisus, Srbija). Ispitano je i analizirano ukupno sedam uzoraka žbuke s različitih lokacija vile s ciljem dobivanja informacija o njezinim morfološkim, mineraloškim, kemijskim i osnovnim fizikalnim karakteristikama. Za utvrđivanje ovih svojstava rabljena je: optička mikroskopija, skenirajući elektronski mikroskop (SEM), s EDS analizom, difrakcijska analiza s X-zrakama (XRD). Žbuka ima prilično ujednačene karakteristike preko cijele površine poda hipokausta. Žbuka dominantno čini karbonatno vezivo i agregat veličine zrna od 0,05 do 2 mm s rijetkom pojavom zrna dimenzija 10 mm. Kao agregat za žbuku rabljeni su dijelovi žbuke, zrna krečnjaka, kvarc, metamorfiti i vulkaniti. Uporaba drobljene opeke i prisustvo reakcijskog ruba, potvrđuje njezinu funkciju hidrauličnog vezivanja. Slaba veza između zrna agregata i krečnjačkog veziva omogućava transport vode kroz formiranu tranzitnu zonu.This paper presents the study of the Roman mortar used for construction of floors in the buildings which possessed floor heating system – hypocaust, in the residential villa with the peristyle (Naisus, Serbia). A total of seven samples of mortar from different locations of the villa were examined and analyzed for information about its morphological, mineralogical, chemical and basic physical properties. In order to determine these properties were used: optical microscopy, the scanning electron microscopy (SEM) with EDS analysis, X-ray diffraction analysis (XRD). The mortar is dominantly made of carbonate binder and the aggregate of grain size 0,05 to 2 mm with a rare occurrence of 10 mm grains. Fragments of mortar, grains of limestone, quartz, metarmorphite and vulcanite were used for the mortar aggregate. Usage of crushed brick and reaction rim confirms its function of hydraulic binder. The weak bonds between the aggregate grains and limestone binder facilitate transport of water through the formed transit zones

European Union enlargement, post-accession migration and imaginative geographies of the ‘New Europe’: media discourses in Romania and the United Kingdom.

This paper is concerned with re-imaginings of ‘Europe’ following the accession to the European Union (EU) of former ‘Eastern European’ countries. In particular it explores media representations of post-EU accession migration from Romania to the United Kingdom in the UK and Romanian newspaper press. Todorova’s (1997) notion of Balkanism is deployed as a theoretical construct to facilitate the analysis of these representations as first, the continuation of long-standing and deeply embedded imaginings of the ‘East’ of Europe and, second, as a means of contesting these discourses. The paper explores the way in which the UK press construct Balkanist discourses about Romania and Romanian migrants, and then analyses how the Romanian press has contested such discourses. The paper argues that the idea of the ‘East’ remains important in constructing notions of ‘Europe’ within popular media geographies

Characterization of Roman mortar from the Mediana archeological site

Ovaj rad prikazuje istraživanje rimske žbuke rabljene za konstrukciju poda u objektima koji su imali sustav podnog grijanja – hipokaust, u rezidencijalnim vilama s peristelom (Naisus, Srbija). Ispitano je i analizirano ukupno sedam uzoraka žbuke s različitih lokacija vile s ciljem dobivanja informacija o njezinim morfološkim, mineraloškim, kemijskim i osnovnim fizikalnim karakteristikama. Za utvrđivanje ovih svojstava rabljena je: optička mikroskopija, skenirajući elektronski mikroskop (SEM), s EDS analizom, difrakcijska analiza s X-zrakama (XRD). Žbuka ima prilično ujednačene karakteristike preko cijele površine poda hipokausta. Žbuka dominantno čini karbonatno vezivo i agregat veličine zrna od 0,05 do 2 mm s rijetkom pojavom zrna dimenzija 10 mm. Kao agregat za žbuku rabljeni su dijelovi žbuke, zrna krečnjaka, kvarc, metamorfiti i vulkaniti. Uporaba drobljene opeke i prisustvo reakcijskog ruba, potvrđuje njezinu funkciju hidrauličnog vezivanja. Slaba veza između zrna agregata i krečnjačkog veziva omogućava transport vode kroz formiranu tranzitnu zonu.This paper presents the study of the Roman mortar used for construction of floors in the buildings which possessed floor heating system – hypocaust, in the residential villa with the peristyle (Naisus, Serbia). A total of seven samples of mortar from different locations of the villa were examined and analyzed for information about its morphological, mineralogical, chemical and basic physical properties. In order to determine these properties were used: optical microscopy, the scanning electron microscopy (SEM) with EDS analysis, X-ray diffraction analysis (XRD). The mortar is dominantly made of carbonate binder and the aggregate of grain size 0,05 to 2 mm with a rare occurrence of 10 mm grains. Fragments of mortar, grains of limestone, quartz, metarmorphite and vulcanite were used for the mortar aggregate. Usage of crushed brick and reaction rim confirms its function of hydraulic binder. The weak bonds between the aggregate grains and limestone binder facilitate transport of water through the formed transit zones

Postcoloniality without race? Racial exceptionalism and south-east European cultural studies

The black Dutch feminist Gloria Wekker, assembling past and present everyday expressions of racialized imagination which collectively undermine hegemonic beliefs that white Dutch society has no historic responsibility for racism, writes in her book White Innocence that ‘one can do postcolonial studies very well without ever critically addressing race’ (p. 175). Two and a half decades after the adaptation of postcolonial thought to explain aspects of cultural politics during the break-up of Yugoslavia created important tools for understanding the construction of national, regional and socio-economic identities around hierarchical notions of ‘Europe’ and ‘the Balkans’ in the Yugoslav region and beyond, Wekker’s observation is still largely true for south-east European studies, where no intervention establishing race and whiteness as categories of analysis has reframed the field like work by Maria Todorova on ‘balkanism’ or Milica Bakić-Hayden on ‘symbolic geographies’ and ‘nesting orientalism’ did in the early 1990s. Critical race theorists such as Charles Mills nevertheless argue that ‘race’ as a structure of thought and feeling that legitimised colonialism and slavery (and still informs structural white supremacy) involved precisely the kind of essentialised link between people and territory that south-east European cultural theory also critiques: the construction of spatialised hierarchies specifying which peoples and territories could have more or less access to civilisation and modernity. South-east European studies’ latent racial exceptionalism has some roots in the race-blind anti-colonial solidarities of state socialist internationalism (further intensified for Yugoslavia through the politics of Non-Alignment) but also, this paper suggests, in deeper associations between Europeanness, whiteness and modernity that remain part of the history of ‘Europe’ as an idea even if, by the end of the 20th century, they were silenced more often than voiced

Large contribution to secondary organic aerosol from isoprene cloud chemistry

Aerosols still present the largest uncertainty in estimating anthropogenic radiative forcing. Cloud processing is potentially important for secondary organic aerosol (SOA) formation, a major aerosol component: however, laboratory experiments fail to mimic this process under atmospherically relevant conditions. We developed a wetted-wall flow reactor to simulate aqueous-phase processing of isoprene oxidation products (iOP) in cloud droplets. We find that 50 to 70% (in moles) of iOP partition into the aqueous cloud phase, where they rapidly react with OH radicals, producing SOA with a molar yield of 0.45 after cloud droplet evaporation. Integrating our experimental results into a global model, we show that clouds effectively boost the amount of SOA. We conclude that, on a global scale, cloud processing of iOP produces 6.9 Tg of SOA per year or approximately 20% of the total biogenic SOA burden and is the main source of SOA in the mid-troposphere (4 to 6 km)

Modelling the long-term dynamics of the energy transition accounting for socioeconomic behaviour and biophysical constraints: overview of the Wiliam Energy Module

WILIAM (Within Limit Integrated Assessment Model) is a global multiregional IAM that combines economic, social, demographic, environmental, energy and material related aspects into one system dynamics model. It aims to provide stakeholders with an open source, welldocumented model to assess the feasibility, effectiveness, costs and impacts of different sustainability policy options. The adequate representation of energy production is key to assess future sustainability pathways. The main function of the developed energy module is to estimate the primary energy requirements and related GHG emissions for satisfying the economic demand. This goal was achieved by 7 major sub-modules: (1) End-use: translates the economic demand into final energy demand through a hybrid approach combining bottom-up with energy intensities for different sectors. (2) Energy transformation: maps the entire energy conversion chain from final to primary energy, including intermediary energy commodities and an allocation function for power plant utilization. (3) Energy capacity: keeps track of the current power plant capacity stock, decommissioning of expired capacities, as well as the build-up of new capacities. An allocation function for choosing the suitable technology types for new capacities stands at the core of this sub-module. (4) Computation of the EROI of green technologies (5) Variability and storage: keeps track of sub-annual time scale effects on annual energy balances depending on the current power system setup (DSM, Storage, sector coupling). (6) Consideration of techno-sustainable potentials of RES considering geographical, resource and Energy Return on Energy Investment (EROI) constraints. (7) Computation of the energy-related GHG emissions

Product platform for automatic configuration of modular strongrooms

© 2020, Strojarski Facultet. All rights reserved. Modular strongrooms (MSR) consist of industrially made elements, which are assembled at the place of use. They are designed on individual customer’s requests. The customer chooses the resistance grade according to EN 1143-1 standard and provides dimensions of the available space for requested product to be fit in. Configuration of MSR is realized by combining standard modules which are, for the selected resistance grade, repeated in each new project, and differ only by their number and dimensions. This paper presents product platform developed for automatic MSR configuration, based on parametric and variable design, which provides requested configuration of the product, eliminates possible errors in design process, provides requested product quality level, decreases design and manufacturing costs, shortens design time and provides faster response to customer’s requests. The proposed concept is tested and confirmed on numerous examples of realized projects

Hydrogenation and hydrodeoxygenation of aromatic lignin monomers over Cu/C, Ni/C, Pd/C, Pt/C, Rh/C and Ru/C catalysts: Mechanisms, reaction micro-kinetic modelling and quantitative structure-activity relationships

In this integrated in silico and experimental study, the activity, selectivity and mechanisms of commercially-available noble and transition metal heterogeneous catalysts, on neutral (carbon) support were investigated for hydrodeoxygenation (HDO) of eugenol. The latter was selected as a model compound of lignin building blocks. An influence of the process operating conditions (temperature, pressure and initial solid loading) on the reaction pathway and product distribution was studied as well. The previously-proposed reaction network for phenols HDO over Ru/C was found valid also for other platinum-group- (Pd, Pt and Rh) and non-noble (Cu or Ni) metallic clusters supported on C. Ru/C system exhibited the best HDO turnover performance, followed by the Rh/C, which especially demonstrated an excellent hydrogenation activity. Pt and Pd showed low deoxygenation and moderate hydrogenation activity. Kinetic parameters for all reactions on the surface were determined for all tested metals with a micro-kinetic model, by regression analysis on the foundation of 5760 experimentally-determined concentration values. Computation took into account resistances caused by transport phenomena, adsorption/desorption kinetics, and especially surface and bulk reaction kinetics. Ratio between adsorption and desorption rate constants for dissolved saturated, aromatic and hydrogen species were predicted, indicating a notable coverage effect on the catalyst reactivity. The saturation of functionalised benzene ring was approximately 3-, 11-, 32-, 10-, and 6-times faster than the C–O hydrogenolysis over ruthenium, platinum, palladium, rhodium and nickel, respectively. Methoxy group removal is easier from aromatics, compared to aliphatic species and also compared to the hydroxyl group removal. The heteroatom bond breaking for 2-methoxy-4-propylcyclohexanol proceed mostly via catechol-type diol formation, and subsequently, de-hydroxylation, particularly observable on Pt