- Published on 27 February 2017
Guest Editors: G. Alimonti, S. Johansson and L. Mariani
After a very long hunting-gathering period, the first agricultural civilizations were born at the end of the last ice age. Agricultural practices generated a surplus of food, which was a prerequisite for the birth of modern societies. During the twentieth century, the modern agriculture was developed and now yields more food than ever before: less than 20% of our global population works to provide the whole mankind with food.
As environmental problems and resource constraints are arising, we now turn to agriculture in the hope for solutions regarding future sustainability. Could agriculture provide us with both food and fuel? Could we contribute to climate change mitigation by letting plants exploit the carbon dioxide that has been accumulated in the atmosphere? There are many promises, and we know that plants are our ultimate companions in life. However, more systemic methods are required to cope with multi-functionality and living systems so that we do not end up causing new problems as we try to cope with those already there.
This EPJ Plus Focus Point addresses the present and historical development of agriculture, perspectives of plant exploitation for food and energy production in a logic of social, economic and environmental sustainability. The articles are freely accessible until 20 April. For further information read the Editorial
EPJ Plus Focus Point - Rewriting Nuclear Physics textbooks: 30 years with radioactive ion beam physics
- Published on 27 February 2017
Guest editors: N. Alamanos, C. Bertulani, A. Bracco, A. Bonaccorso, D. Brink and G. Casini
This collection of articles contains the lectures given at the Summer School "Re-writing Nuclear Physics textbooks: 30 years of radioactive ion beam physics`` which was held at the INFN Sezione di Pisa and Department of Physics of the University of Pisa during the week 20-24 July 2015.
The school celebrated thirty years since the publication of the first papers (I. Tanihata et al., Phys. Rev. Lett. 55, (1985) 2676 and P.G. Hansen, B. Jonson, Europhys. Lett. 4, (1987) 409) in which radioactive ion beams (RIBs) were used to study properties of atomic nuclei. The school consisted of twelve lectures published here and freely accessible until 24 April 2017. Each lecture covers a topic contained in a standard Nuclear Physics textbook extended to show how our understanding has deeply changed due to the experience accumulated with RIB physic. The collection is directed mainly to third and fourth year undergraduate students but it could be seen also as an update for teachers of basic Nuclear Physics courses.
For further information read the Editorial here.
- Published on 20 February 2017
New study reveals characteristic of islands of magnetic metals between vacuum gaps, displaying tunnelling electric current
The nanometric-size islands of magnetic metal sporadically spread between vacuum gaps display unique conductive properties under a magnetic field. In a recent study published in EPJ Plus, Anatoliy Chornous from Sumy State University in Ukraine and colleagues found that the vacuum gaps impede the direct magnetic alignment between the adjacent islands - which depends on the external magnetic field - while allowing electron tunneling between them. Such externally controlled conducting behaviour opens the door for applications in electronics with magnetic field sensors - which are used to read data on hard disk drives - biosensors and microelectromechanical systems (MEMS), as well as in spintronics with magnetic devices used to increase memory density.
- Published on 20 January 2017
To switch electricity supply from nuclear to wind and solar power is not so simple
Germany decided to go nuclear-free by 2022. A CO2-emission-free electricity supply system based on intermittent sources, such as wind and solar - or photovoltaic (PV) - power could replace nuclear power. However, these sources depend on the weather conditions. In a new study published in EPJ Plus, Fritz Wagner from the Max Planck Institute for Plasma Physics in Germany analysed weather conditions using 2010, 2012, 2013 and 2015 data derived from the electricity supply system itself, instead of relying on meteorological data. By scaling existing data up to a 100% supply from intermittent renewable energy sources, the author demonstrates that an average 325 GW wind and PV power are required to meet the 100% renewable energy target. This study shows the complexity of replacing the present primary energy supply with electricity from intermittent renewable sources, which would inevitably need to be supplemented by other forms of CO2-free energy production.
- Published on 05 December 2016
Scientists have now adopted a qualitative theoretical neuroscience model commensurate with actual measurements of neurons' dynamics
Neuroscientists are currently working diligently to understand the dynamics of thousands of coupled neurons. Understanding how they operate requires accurate models. The trouble is that each of the existing neuroscience models has its own shortcomings. Russian physicists have, for the first time, developed an effective method for solving the equations of a well-known theoretical neuroscience dynamic model and make it more biologically relevant. These findings have just been published in EPJ Plus by Eugene Postnikov and Olga Titkova from Kursk State University, Russia. They could not only help resolve problems in the neurosciences, but could also provide a deeper understanding of neuronal activity in the emerging sector of neurovascular dynamics, which describes the interplay between the brain's neurons and the blood flow.
- Published on 12 October 2016
New method to make permanent magnets more stable over time
For physicists, loss of magnetisation in permanent magnets can be a real concern. In response, the Japanese company Sumitomo created the strongest available magnet—one offering ten times more magnetic energy than previous versions—in 1983. These magnets are a combination of materials including rare-earth metal and so-called transition metals, and are accordingly referred to as RE-TM-B magnets. A Russian team has now been pushing the boundaries of magnet design, as published in a recent study in EPJ Plus. They have developed methods to counter the spontaneous loss of magnetisation, based on their understanding of the underlying physical phenomenon. Roman Morgunov from the Institute of Problems of Chemical Physics at the Russian Academy of Sciences and colleagues have now developed a simple additive-based method for ensuring the stability of permanent magnets over time, with no loss to their main magnetic characteristics.
- Published on 25 July 2016
Testing liquid metals as target material bombarded by high-energy particles
There is a growing interest in the scientific community in a type of high-power neutron source that is created via a process referred to as spallation. This process involves accelerating high-energy protons towards a liquid metal target made of material with a heavy nucleus. The issue here is that scientists do not always understand the mechanism of residue nuclei production, which can only be identified using spectrometry methods to detect their radioactive emissions. In a new study examining the radionuclide content of Lead-Bismuth-eutectic (LBE) targets, scientists at the Paul Scherrer Institute Villigen (PSI) found that some of the radionuclides do not necessarily remain dissolved in the irradiated targets. Instead, they can be depleted in the bulk LBE material and accumulate on the target's internal surfaces. These findings have recently been published in EPJ Plus by Bernadette Hammer-Rotzler affiliated with the PSI and the University of Bern, Switzerland, and colleagues from Switzerland, France and Sweden. The results improve our understanding of nuclear data related to the radionuclides stemming from high-power targets in spallation neutron sources. They contribute to improving the risk assessment of future high-power spallation neutron beam facilities --including, among others, the risk of erroneous evaluation of radiation dose rates.
- Published on 13 June 2016
Replacing nuclear power with wind power doesn't make sense in Sweden, study shows
The Swedish power supply is largely free of carbon emissions. Indeed, it is mainly based on a combination of hydroelectric and nuclear power combined with power exchange with neighbouring Scandinavian countries. A study published in EPJ Plus investigates the possibility of replacing nuclear power with wind power, which is by nature intermittent. According to the study, this, in turn, would finally lead to a reduction in the use of hydroelectricity if the annual consumption remained constant. The authors of the study conclude that a backup system, based on fossil fuel, namely gas, would be required in combination with wind power. In such a scenario, the CO2 emissions would double. Fritz Wagner from the Max Planck Institute for Plasmaphysics, Greifswald, Germany, and Elisabeth Rachlew from the Royal Institute of Technology, Stockholm, Sweden, therefore conclude that it would not be a viable option.
- Published on 11 May 2016
Extension of the relativity theory to rotational motion, one hundred years after Einstein first published the general theory of relativity
It has been one hundred years since the publication of Einstein’s general theory of relativity in May 1916. In a paper recently published in EPJ Plus, Norwegian physicist Øyvind Grøn from the Oslo and Akershus University College of Applied Sciences and his co-author Torkild Jemterud demonstrate that the rotational motion in the universe is also subject to the theory of relativity.
- Published on 05 April 2016
New study highlights the role of electron diffusivity when turning waste heat into electricity
Many phenomena in physics, though well-known, are not necessarily widely understood. That’s the case with thermoelectricity, which harnesses waste heat by coupling heat flux and electric current. However, understanding such phenomena is important in order to leave the door open for discovering novel manifestations of them. Thus, even today physicists working in the area of thermoelectricity continue to ask fundamental questions about the underlying physical process. For example, in a recent study, a team based in France questioned the nature of the force that puts electrons to work when a temperature difference is applied across a thermoelectric material. Now, Henni Ouerdane, affiliated to the Russian Quantum Center near Moscow, and colleagues have published in EPJ Plus a study showing that the force that puts electrons to work to harness the waste heat is linked to the ability of electrons to diffuse through the material. Potential applications in the field of electrical power production from waste heat include thermoelectric devices designed to boost power over a range spanning ten orders of magnitude: typically from microwatts to several kilowatts.