Size-resolved characteristics of inorganic ionic species in atmospheric aerosols at a regional background site on the South African Highveld     

Andrew D. Venter  Pieter G. van Zyl  Johan P. Beukes  Jan-Stefan Swartz  Miroslav Josipovic  Ville Vakkari  Lauri Laakso  Markku Kulmala 《Journal of Atmospheric Chemistry》2018,75(3):285-304

Aerosols consist of organic and inorganic species, and the composition and concentration of these species depends on their sources, chemical transformation and sinks. In this study an assessment of major inorganic ions determined in three aerosol particle size ranges collected for 1 year at Welgegund in South Africa was conducted. SO₄^2? and ammonium (NH₄⁺) dominated the PM₁ size fraction, while SO₄^2? and nitrate (NO₃) dominated the PM_1–2.5 and PM_2.5–10 size fractions. SO₄^2? had the highest contribution in the two smaller size fractions, while NO₃^? had the highest contribution in the PM_2.5–10 size fraction. SO₄^2? and NO₃^? levels were attributed to the impacts of aged air masses passing over major anthropogenic source regions. Comparison of inorganic ion concentrations to levels thereof within a source region influencing Welgegund, indicated higher levels of most species within the source region. However, the comparative ratio of SO₄^2? was significantly lower due to SO₄^2? being formed distant from SO₂ emissions and submicron SO₄^2? having longer atmospheric residencies. The PM at Welgegund was determined to be acidic, mainly due to high concentrations of SO₄^2?. PM₁ and PM_1–2.5 fractions revealed a seasonal pattern, with higher inorganic ion concentrations measured from May to September. Higher concentrations were attributed to decreased wet removal, more pronounced inversion layers trapping pollutants, and increases in household combustion and wild fires during winter. Back trajectory analysis also revealed higher concentrations of inorganic ionic species corresponding to air mass movements over anthropogenic source regions.  相似文献   

Fundamental physical constants,quark models and final parameters of the universe     

Vladimír Skalský  Miroslav Súkeník 《Astrophysics and Space Science》1996,236(2):295-298

From the values of the fundamental physical constantsc, G. andh and the quark models result the final parameters of the universe.  相似文献   

Developing a reduced-form ensemble of climate change scenarios for Europe and its application to selected impact indicators     

Martin Dubrovsky  Miroslav Trnka  Ian P. Holman  Eva Svobodova  Paula A. Harrison 《Climatic change》2015,128(3-4):169-186

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Radio-continuum study of the nearby sculptor group galaxies. Part 3: NGC 7793 at λ=12.2, 6 and 3 cm     

Timothy J. Galvin  Miroslav D. Filipović  Nicholas F. H. Tothill  Evan J. Crawford  Andrew N. O’Brien  Nicholas Seymour  Thomas G. Pannuti  Alekzander R. Kosakowski  Biswas Sharma 《Astrophysics and Space Science》2014,353(2):603-611

We re-examine a series of archived centimetre radio-continuum observations (λ=16, 6 and 3 cm) focusing on NGC?7793 using the Australia Telescope Compact Array. These new images are both very sensitive (σ=0.011 mJy/beam) and feature reasonably high angular resolution (down to <3″). Using these images, a total of 76 discrete radio sources are identified, of which 57 have been classified. We also studied the radio component of the micro-quasar NGC7793-S26 which shows two distinct regions of somewhat steep spectral index (α) between ?0.3 and ?0.7.  相似文献   

Parameters of the ultrastable expansive nondecelerative universe     

Vladimír Skalský  Miroslav Súkeník 《Astrophysics and Space Science》1994,215(1):137-147

The measurement of the temperature of the cosmic microwave background radiation (CMBR) with the Far InfraRed Absolute Spectrophotometer (FIRAS) on the Cosmic Background Explorer (COBE) satellite gives a possibility for determination of all mutually related parameters of the ultrastable expansive nondecelerative Universe (ENU) with deviations smaller than 0.4%.The measurement of the large-scale anisotropy of the CMBR with the Differential Microwave Radiometers (DMR) on the COBE satellite allows us to determine the mass density of gravitationally bound systems of large-scale structures of the ENU.  相似文献   

Specific problems of ore prospection geophysics in regions of arid climate     

Miroslav Krs 《Pure and Applied Geophysics》1972,98(1):163-172

Summary The present communication deals with problems that are common to the application of some geophysical methods in arid regions. Typical examples of using geothermic methods, D.C. and A.C. electrical and radiometric methods in the Eastern Desert of Egypt are presented. The conclusions were derived from a great number of measurements and are all associated with the physical properties of rocks on or near the surface under desert conditions.  相似文献   

Croatia and Central Europe — the geopolitical relationship     

Duško Topalović  Miroslav Krleža 《GeoJournal》1996,38(4):399-405

The position of Croatia on the border of larger geographic wholes (Central Europe, the Mediterranean, the Balkans) makes it a transitional region for these larger areas. However, the Pannonian region of Croatia, as the largest part of its national territory, places it in the ranks of the Central European states. The long historical ties of the Croatian lands with the Austrian and Hungarian centers of Central European power also confirm Croatia's affiliation with Central Europe. The cultural, civilization, religious and other characteristics, which today ease Croatia's communications with Central European countries, are unavoidable. With state independence, Croatia acquired the political sovereignty vital for its Central European orientation and was liberated from the problems of the Balkans, although it is still struggling for its territorial integrity. Croatian statehood was realized soon after the reunification of Germany, which in fact renewed the concept and content of Central Europe. This fact opened many questions tied to the rivalry and political balance of the European powers, which is also connected to the geopolitical position of Croatia.  相似文献   

New Towns and their environment     

Dr. Miroslav Strida 《GeoJournal》1978,2(1):35-38

The environment has, ins a regional sense, the function of usefulness and the function of housing both being very often contradictory. The prospects of New Towns reduce the occurrence of such conflicts and bring some possibilities for applied-geography-intervention. In the densely populated countries of Central Europe mining, manufacturing, administrative and regional utilization are the main decisive functions in the developing for the origin, localization and prosperity of New Towns.  相似文献   

An analysis of the palaeomagnetic field     

Miroslav Krs  Reviewer J. Kropáček 《Studia Geophysica et Geodaetica》1978,22(4):368-389

Summary The paper is devoted to a critical evaluation of the hypothesis of the prevalent character of the palaeomagnetic field in the course of the whole Phanerozoic. The study ties in with the synthetic processing of all so far published palaeomagnetic data for Eurasia and Africa respecting some of the models ensuing from the concept of plate tectonics. Initial material for testing the dipolar hypothesis was obtained by statistical processing of the palaeomagnetic pole positions and by analyzing the values of the so-called palaeorotation, the palaeoinclination difference and of palaeodivergence. It was shown that, by defining tectonically stable blocks (plates, palaeoplates) within the scope of the Eurasian continent and within the scope of the African continent as a whole, data were obtained bringing evidence of the predominating dipolar character of the mean geomagnetic field for the period from the Quaternary to the Cambrian, with the exception of the Silurian which has not been studied sufficiently. The deviations of the palaeomagnetic directions from the direction of the dipolar field within the scope of the stable blocks have the character of a Gaussian distribution and the standard deviations only amount to a few degrees.  相似文献   

The first satellite laser ranging at ondřejov observatory     

Petr Lála  Miroslav Prokeš  Reviewer M. Burša 《Studia Geophysica et Geodaetica》1976,20(4):391-395

Summary The first laser ranging of the satellites Geos A and B performed at Station 1148 Ondejov in 1972–1975 are evaluated. The least-squares method was used to estimate their internal accuracy. Polynomials of the 6th to 8th degree were found to be necessary for the best fit of a typical satellite pass. The root mean square error is always smaller than 20 ns (3 m), which is consistent with the expected accuracy of the laser ranging system.Dedicated to Prof. RNDr. Emil Buchar, DrSc., Corresponding Member of the Czechoslovak Academy of Sciences, on the Occasion of His 75^th Birthday  相似文献