Physical conditions in CaFe interstellar clouds

Interstellar clouds that exhibit strong Ca I and Fe I lines were called CaFe clouds. The ionisation equilibrium equations were used to model the column densities of Ca II, Ca I, K I, Na I, Fe I and Ti II in CaFe clouds. The chemical composition of CaFe clouds is that of the Solar System and no depletion of elements onto dust grains is seen. The CaFe clouds have high electron densities n=1 cm^-3 that leads to high column densities of neutral Ca and Fe.Comment: Changed content, figure adde

On reflection of Alfven waves in the solar wind

We have revisited the problem of propagation of toroidal and linear Alfven waves formulated by Heinemann and Olbert (1980) to compare WKB and non-WKB waves and their effects on the solar wind. They considered two solar wind models and showed that reflection is important for Alfven waves with periods of the order of one day and longer, and that non-WKB Alfven waves are no more effective in accelerating the solar wind than WKB waves. There are several recently published papers which seem to indicate that Alfven waves with periods of the order of several minutes should be treated as non-WKB waves and that these non-WKB waves exert a stronger acceleration force than WKB waves. The purpose of this paper is to study the origin of these discrepancies by performing parametric studies of the behavior of the waves under a variety of different conditions. In addition, we want to investigate two problems that have not been addressed by Heinemann and Olbert, namely, calculate the efficiency of Alfven wave reflection by using the reflection coefficient and identify the region of strongest wave reflection in different wind models. To achieve these goals, we investigated the influence of temperature, electron density distribution, wind velocity and magnetic field strength on the waves. The obtained results clearly demonstrate that Alfven wave reflection is strongly model dependent and that the strongest reflection can be expected in models with the base temperatures higher than 10(exp 6) K and with the base densities lower than 7 x 10(exp 7) cm(exp -3). In these models as well as in the models with lower temperatures and higher densities, Alfven waves with periods as short as several minutes have negligible reflection so that they can be treated as WKB waves; however, for Alfven waves with periods of the order of one hour or longer reflection is significant, requiring a non-WKB treatment. We also show that non-WKB, linear Alfven waves are always less effective in accelerating the plasma than WKB Alfven waves. Finally, it is evident from our results that the region of strongest wave reflection is usually located at the base of the models, and hence that interpretation of wave reflection based solely on the reflection coefficient can be misleading

Alfven Waves and Turbulence in the Solar Atmosphere and Solar Wind

We solve the problem of propagation and dissipation of Alfvenic turbulence in a model solar atmosphere consisting of a static photosphere and chromosphere, transition region, and open corona and solar wind, using a phenomenological model for the turbulent dissipation based on wave reflection. We show that most of the dissipation for a given wave-frequency spectrum occurs in the lower corona, and the overall rms amplitude of the fluctuations evolves in a way consistent with observations. The frequency spectrum, for a Kolmogorov-like slope, is not found to change dramatically from the photosphere to the solar wind, however it does preserve signatures of transmission throughout the lower atmospheric layers, namely oscillations in the spectrum at high frequencies reminiscent of the resonances found in the linear case. These may disappear once more realistic couplings for the non-linear terms are introduced, or if time-dependent variability of the lower atmospheric layer is introduced.Comment: 27 pages, 9 figures, accepted for publication in Ap

Properties of Electrodeposited CuSCN 2D Layers and Nanowires Influenced by Their Mixed Domain Structure

International audienc

The Effect of Wind on the Sedimentation in Offshore Areas of Water Reservoirs

Na koncentrację zawiesin w wodzie morskiej wpływa wiele czynników. Są to między innymi: odległość od ujścia rzeki, budowa geologiczna brzegu i dna morskiego, kierunek i prędkość prądów pływowych i dryfowych oraz stopień sfalowania morza. Przedstawiono wyniki badań pokazujące wpływ siły wiatru na zjawisko sedymentacji w przybrzeżnych obszarach zbiorników wodnych.There are many factors which influence the concentration of suspension in sea water. These includethe distance from the estuary, geological structure of the shore and seabed, direction and speed of tidal current and drift, as well as wave height. The results of research presented in the article show the effect of the wind force on the sedimentation in offshore areas of water reservoirs

Total Internal Reflection as a Method for the Determination of Hydrocarbon Content in Water

Przez wiele lat pomiary zanieczyszczenia wody produktami ropopochodnymi były wykonywane z użyciem transmisyjnej metody spektrofotometrii absorpcyjnej w podczerwieni. Jednakże metoda ta musi ulec modyfikacji ze względu na wprowadzony w 2003 roku zakaz stosowania czterochlorku węgla, używanego w tej metodzie jako rozpuszczalnik. Inną metodą badania absorpcji w podczerwieni jest metoda HATR, gdzie jako rozpuszczalnik może być użyty benzen. W artykule opisano tę metodę oraz przedstawiono jej zalety i wady .For many years the analysis of concentration residual hydrocarbon and oil in samples of water and soil has been performed using transmission infrared spectroscopy. However, this method will have to be modified due to the prohibition of the use of carbon tetrachloride, used as a solvent in this method. Another method of measuring the absorption of infrared radiation is horizontal attenuated total reflection( HATR), where benzene could be used as a solvent. A description of the HATR method, its advantages and disadvantages are presented

Strontium isotopes as environmental tracers for identification of groundwater circulation in multi-layered aquifer systems

The results of the research concerning measures of strontium isotopes and concentrations, were presented in this article. This environmental tracers occuring in groundwater and surface water allowed for the preliminary identification of groundwater circulation in the multi-layered aquifer system. The study area concerned Żarnowiecka Upland and Valley of the Żarnowieckie Lake with the Piaoenica river, where the occurrence of 3 to 5 aquifers in Quaternary, Miocene and Oligocene was confirmed. The valley area is also the Main Groundwater Reservoir (MGR) No. 109. The results clearly indicated on substantial differences in the values of 87Sr/86Sr isotopic signatures and strontium concentrations in each of aquifers. These differences made possible to determine the percentage of the groundwater in the Piaoenica drained from the upland and from the valley. Calculations showed the groundwater component from the upland may constitute up to 80% of river water, and the river is a regional drainage base even for the Oligocene aquifer occurring at a depth of approx. 200 m. The results confirmed no link between the shallowest aquifers occurring in the upland, and the drainage role of the Piaśnica river. The characteristic of shallow groundwater is similar to the rainwater

Spectroscopic Investigation of Oil Pollution on the Surface and at Various Depths of the Odra River

Wskazano na postępujący proces degradacji środowiska naturalnego Morza Bałtyckiego i rzeki Odry, wynikający z przedostających się do akwenów produktów ropopochodnych. Wskazano na obszar objęty pomiarami oraz metodykę prowadzenia badań. Na podstawie wieloletnich pomiarów podano uśrednione wyniki zaolejenia na powierzchni wód estuarium Odry. Przeprowadzono sondażowe badania rozkładu pionowego zanieczyszczeń olejowych wody w wybranych punktach estuarium Odry.The process of progressive degradation of natural environment of the Baltic Sea and the Odra River caused by oil products has been presented. The authors describe the examined area and measurement techniques. The mean values of oil contamination of the Odra River superficial layer have been calculated on the basis of measurements carried out for many years. Besides, the distribution of the oil pollution of water in the perpendicular cross-section at selected points of the Odra River has been presented