Extensometric observation of Earth tides and local tectonic processes at the Vyhne station, Slovakia

Abstract The Vyhne Tidal Station of the Earth Science Institute of the Slovak Academy of Sciences is located in the former mining gallery of St. Anthony of Padua in the Vyhne valley, Štiavnické vrchy Mts., Central Slovakia. It is equipped with a 20.5 metre long quartz-tube extensometer measuring Earth’s tides, and long-term tectonic deformations of the Earth’s crust. Data between 2001 and 2015 with some diverse gaps were digitally collected, processed and analysed. The effects of the local conditions, such as structure of the observatory, cavity effect, topography and geological features of the surrounding rocks, were investigated in detail and these effects were taken into consideration during the interpretation of the results of the data analysis. Tidal analysis of the extensometric data between 2005 and 2015 revealed that the measured tidal amplitudes are close to the theoretical values. The tidal transfer of the observatory was also investigated by coherence analysis between the theoretical and the measured extensometric data. The coherence is better than 0.9 both in the diurnal and semidiurnal band. The effect of the free core nutation resonance was also investigated in the case of the K1 and P1 tidal components. Since the K1/O1 ratio was about the theoretical value 0.8, than the P1/O1 was between 1.0 and 1.15 instead of the theoretical value of 0.9. The rate of the long-term strain rate was also investigated and the obtained −0.05 μstr/y shows a good agreement with the strain rate inferred from GPS measurements in the Central European GPS Reference Network.</jats:p

Assembly and Interaction of Polyaniline Chains: Impact on Electro- and Physical–Chemical Behavior

Polyaniline (PANI) is one of the promising candidates for utilization as electrode material in supercapacitors, and its electro- and physical–chemical properties have been studied for several decades. However, there are fundamental questions that need to be answered. For example, is it possible to obtain and characterize individual PANI chains or what is the impact of chains interactions on electro- and physical–chemical behavior? To that end, we isolated and characterized individual PANI chains alongside nanofibrillar assemblies for the first time, and moreover, we demonstrate that the interaction between polyaniline chains and their assembly into nanofibrils have a crucial impact on electro- and physical–chemical behaviors of PANI. Additionally, the optical transitions of three different conglomerations and protonation states are studied and correlated with the structural and electrochemical characterization. The mechanism of the redox process for individual PANI chains and PANI nanofibrils is proposed. The specific capacitance of 1050 F/g (at 25 A/g of specific current) for three-electrode configuration and 450 F/g (at 9 A/g of specific current) for two-electrode configuration was obtained, which is the highest value reported to date

The Theoretical Description for the Perylaldehyde Aldoxime Electrochemical Determination, Assisted by the Novel Squaraine Dye – VO(OH) - Composite

For the first time, the perillaldehyde aldoxime electrochemical determination has been evaluated from the theoretical point of view. The correspondent mathematical model, including different scenarios of the electroanalytical process, has been developed and analyzed by means of linear stability theory and bifurcation analysis. The model analysis clearly shows that the composite of a squaraine dye in organic phase and vanadium oxyhydroxide in the inorganic phase may be an efficient electrode modifier for perillaldehyde aldoxime electrochemical determination. On the other hand, both oscillatory and monotonic instabilities may be realized in the electroanalytical process, and their probability will strongly depend on the direction of the electroanalytical scenario in the concrete conditions. DOI: http://dx.doi.org/10.17807/orbital.v12i3.1498</p

The Trans-Atlantic Slocum Glider Expeditions: A Catalyst for Undergraduate Participation in Ocean Science and Technology

Results of Office of Naval Research (ONR)- and National Science Foundation (NSF)-sponsored collaborative coastal science experiments using underwater gliders were reported at the E.U./U.S. Baltic Sea conference in 2006. The National Oceanic and Atmospheric Administration (NOAA) recognized the parallel educational potential and issued a trans-Atlantic challenge—modify one of the coastal gliders and fly it across the Atlantic, entraining and inspiring students along the way. Leveraging the experience of the NSF Centers for Ocean Sciences Education Excellence, a needs assessment process guided the development of a new undergraduate research program based on the cognitive apprenticeship model. The generalized model was applied to the specific opportunities provided by the trans-Atlantic challenge, involving students in every aspect of the missions. Students participated in the modifications and testing required to increase glider endurance and in the development of the mission planning tools. Scientist and student teams conducted three long-duration missions: (1) RU15’s flight from New Jersey to Nova Scotia to test the lithium batteries and ruggedized fin technology in storms, (2) RU17’s first attempt at the Atlantic crossing that provided the lessons learned, and (3) RU27’s successful trans-Atlantic flight a year later. Post-flight activities included development of new intuitive glider data visualization software that enabled students to analyze the glider data and compare it with ocean forecast models, enabling students to create their own new knowledge. Lessons learned include the significant gains achieved by engaging students early, encouraging them to work as teams, giving them the tools to make their own discoveries, and developing a near-peer mentoring community for increasing retention and diversity. The success has inspired an even broader vision for international glider missions, that of a glider-enabled global classroom to repeat the track of the HMS Challenger and its first scientific circumnavigation of the globe