News
EPJ E Highlight - Space lab to elucidate how liquid cocktails mix
- Details
- Published on 08 May 2015
Zero-gravity experiments can tell us a great deal about the effects of temperature change on the concentrations of three different liquids that are mixed together
What does space experimentation have in common with liquid cocktails? Both help in understanding what happens when multiple fluids are mixed together and subjected to temperature change - a phenomenon ubiquitous in nature and industrial applications such as oil fluids contained in natural reservoirs. The latest experimental data performed in zero gravity on the International Space Station is now available in the newly published Topical Issue of EPJ E. The results constitute the first set of highly accurate and broadly validated data on the thermodiffusion effects that occur when three different liquids are mixed. Such experiments were made possible by a collaboration of space agencies including the ESA, NASA, CSA and ROSCOSMOS.
EPJ B Highlight - Noise produces volcanic seismicity, akin to a drumbeat
- Details
- Published on 06 May 2015
A new study shows that relatively small external disturbances play a crucial role in chaotic phenomena like the recent Calbuco volcanic eruption in Chile, leading to drum-beat-like seismicity
Volcanoes are considered chaotic systems. They are difficult to model because the geophysical and chemical parameters in volcanic eruptions exhibit high levels of uncertainty. Now, Dmitri V. Alexandrov and colleagues from the Ural Federal University in Ekaterinburg, in the Russian Federation, have further extended an eruption model - previously developed by other scientists - to the friction force at work between the volcanic plug and volcanic conduit surface. The results, published in EPJ B, provide evidence that volcanic activity can be induced by external noises that would not otherwise have been predicted by the model.
EPJ Data Science Highlight - Big Data reveals classical music creation secrets
- Details
- Published on 29 April 2015
Study uncovers how classical music composers collaborate, mix, and influence one another. Results show how culture evolves and predict the future of the recording market
A team of scientists has shed light on the dynamics of the creation, collaboration and dissemination processes involved in classical music works and styles. Their study focuses on analysing networks of composers contemporary to CD publications, using modern data analysis and data modelling techniques. These findings have just been published in EPJ Data Science by Doheum Park from the Graduate School of Culture Technology at Korea Advanced Institute of Science and Technology in Daejeon and colleagues. This work explores the nature of culture in novel ways, as part of a broader movement of applying quantitative methods to music, the visual arts and literature.
EPJ D Highlight - Novel plasma diagnostics method
- Details
- Published on 15 April 2015
Physicists have now devised an elegant plasma pressure diagnostic method by studying forces akin to the pressure change at the inner walls of energy saving light bulb when the light is switched on
Could the mundane action of switching on an energy saving light bulb still hold secrets? It does, at least for physicists. These bulbs are interesting because they contain low-temperature plasma—a gas containing charges from ions and electrons. Now, a German team has developed a method that could be used for measuring the increase in the plasma force on the inner side of such a light bulb when the light is switched on. These findings from Thomas Trottenberg and colleagues from Christian-Albrechts University in Kiel, Germany, have just been published in EPJ D. They have implications for plasma diagnostics concerning plasma-wall interactions used in surface modification and the production of thin film solar cells and microchips.
EPJ TI Review - Applications of Raman micro-spectroscopy to stem cell technology
- Details
- Published on 14 April 2015
This short review, part of the Thematic Series on Raman Spectroscopies, describes the application of Raman micro-spectroscopy to measure the molecular properties of stem cells during differentiation in-vitro. The paper focuses on time- and spatially-resolved Raman spectral measurements that allow repeated investigation of live stem cells in-vitro.
EPJ Plus Highlight - Accurate dating requires calibration down to the last ion
- Details
- Published on 14 April 2015
A new solution accurately counting the exact amounts of ions from laboratory radiation exposure helps to simulate the natural radiation of quartz samples used for thermoluminescence dating
Thermoluminescence is used extensively in archaeology and the earth sciences to date artefacts and rocks. When exposed to radiation quartz, a material found in nature, emits light proportional to the energy it absorbs. Replicating the very low dose of background radiation from natural sources present in quartz is a key precondition for precise and accurate dating results. Italian scientists have now developed a method to control the accuracy of the dose calibrations delivered to the samples during laboratory irradiation with heavy particles, replicating natural radiation exposure. These findings have just been published by Lara Palla from the National Institute of Nuclear Physics (INFN), Italy, and colleagues in a paper in EPJ Plus. Using oxygen and lithium ions from the Tandem accelerator at INFN LABEC in Florence, they found that their measurements were accurate to within 1%, despite large fluctuations in the irradiation beam.
EPJ E Highlight - Rodeo in liquid crystal
- Details
- Published on 30 March 2015
Scientists have achieved an unprecedented level of control over defects in liquid crystals that can be engineered for applications in liquid matter photonics
Sitting with a joystick in the comfort of their chairs, scientists can play “rodeo” on a screen magnifying what is happening under their microscope. They rely on optical tweezers to manipulate an intangible ring created out of liquid crystal defects capable of attaching a microsphere to a long thin fibre. Maryam Nikkhou and colleagues from the Jožef Stefan Institute, in Ljubljana, Slovenia, recently published in EPJ E the results of work performed under the supervision of Igor Muševič. They believe that their findings could ultimately open the door to controlling the flow of light using light of a specific frequency in the Gigahertz range in liquid crystal photonic microdevices.
EPJ A Highlight - Pionic-Hydrogen Atom and Quantum Chromodynamics
- Details
- Published on 30 March 2015
Analogous to the vast amount of knowledge acquired on the electronic hydrogen atom over the last century and the success of Quantum Electrodynamics (QED), hadronic physics is using a similar system, namely “pionic hydrogen” - a hydrogen atom where the electron is replaced by a negatively charged pion - as a laboratory for investigating Quantum Chromodynamics (QCD). Like in electronic hydrogen the finite size of the proton plays a role in the precise determination of the ground state of the atom. The smaller Bohr radius of the pion offers a larger sensitivity to the strong interaction between the pion and the proton, leading, e.g., to an energy shift compared to the ground state energy if only the electromagnetic interaction is considered. The precise determination of this shift provides a benchmark of our understanding of the pion-proton strong interaction from basic principles in QCD. To this end an exquisite experiment was devised and performed at the high intensity, low energy pion beam at the Paul Scherrer Institut using a cyclotron trap and an ultimate resolution Bragg spectrometer leading to an impressive four fold improvement compared to the previous best measurement as shown in Fig. 1.
New associate editors in EPJ AP
- Details
- Published on 27 March 2015
EPJ Applied Physics has appointed some new associate editors over the last two months and we are very pleased to introduce our new team and their expertise.
EPJAP now stands poised to continue its original goal to become an influential international journal. The recently appointed editors will contribute to its progress with new ideas and perspectives. They are all professional, outstanding scientist who have a vast experience and are strongly motivated towards excellence. We expect that the new editorial board will increase the benefits of the EPJAP's readers and authors even further in the future.
EPJ E Highlight - Building sound foundations: a matter of granular dynamics
- Details
- Published on 25 March 2015
Applying the hydrodynamics approach to granular matter helps explain its wide range of behaviour, regardless of whether the material is solid- or fluid-like
Sand, rocks, grains, salt or sugar are what physicists call granular media. A better understanding of granular media is important - particularly when mixed with water and air, as it forms the foundations of houses and off-shore windmills. Until recently, there was no single theory that could account for granular media’s flows at different speeds. Now, a new theory dubbed GSH, which stands for granular solid hydrodynamics, is supplementing previous models of granular material that work only for narrow speed ranges. And Yimin Jiang from Central South University, Changsha, China and Mario Liu from the University of Tübingen, Germany have now applied GSH to different experimental circumstances, for a wide range of flow speeds, in a study published in EPJ E.
