scholarly journals Spatial Distribution of Chemical Components in Fresh Snow in the Japanese Alps Region

2013 ◽  
Vol 122 (4) ◽  
pp. 651-665 ◽  
Author(s):  
Takayuki KURAMOTO ◽  
Daichi SUZUKI ◽  
Akihiko SASAKI ◽  
Keisuke SUZUKI
Keyword(s):  
Spatial Distribution ◽  
Chemical Components ◽  
Fresh Snow

scholarly journals Chemical characteristics of snow in the region along the Sea of Japan

1993 ◽  
Vol 18 ◽  
pp. 227-233 ◽  
Author(s):  
Kazuhide Satow
Keyword(s):  
Spatial Distribution ◽  
Electric Conductivity ◽  
Sea Of Japan ◽  
Ph Value ◽  
Chemical Components ◽  
Chemical Characteristics ◽  
The Sea Of Japan ◽  
Heavy Snowfall ◽  
Asian Continent ◽  
Ph Values

The amount of acidity in precipitation has been measured in heavy-snowfall regions facing the Sea of Japan. The average pH value of precipitation measured throughout the year at Nagaoka was 4.80 during 4.5 years, 1987–92. During winter the pH value is lower and electric conductivity higher. The spatial distribution of chemical components in new-fallen snow was studied along a 55 km-long sampling route. Results from four surveys showed that acidic snows have average pH values of 4.63–4.90. From the distribution of anion and cation concentration in new-fallen snow, it is concluded that strong northwest monsoons during winter bring an abundance of snow with salt components and many non-salt components from the Sea of Japan and also, possibly, from the Asian continent.

scholarly journals Chemical characteristics of snow in the region along the Sea of Japan

1993 ◽  
Vol 18 ◽  
pp. 227-233 ◽  
Author(s):  
Kazuhide Satow
Keyword(s):  
Spatial Distribution ◽  
Electric Conductivity ◽  
Sea Of Japan ◽  
Ph Value ◽  
Chemical Components ◽  
Chemical Characteristics ◽  
The Sea Of Japan ◽  
Heavy Snowfall ◽  
Asian Continent ◽  
Ph Values

The amount of acidity in precipitation has been measured in heavy-snowfall regions facing the Sea of Japan. The average pH value of precipitation measured throughout the year at Nagaoka was 4.80 during 4.5 years, 1987–92. During winter the pH value is lower and electric conductivity higher. The spatial distribution of chemical components in new-fallen snow was studied along a 55 km-long sampling route. Results from four surveys showed that acidic snows have average pH values of 4.63–4.90. From the distribution of anion and cation concentration in new-fallen snow, it is concluded that strong northwest monsoons during winter bring an abundance of snow with salt components and many non-salt components from the Sea of Japan and also, possibly, from the Asian continent.

scholarly journals Airborne measurements of the spatial distribution of aerosol chemical composition across Europe and evolution of the organic fraction

2010 ◽  
Vol 10 (8) ◽  
pp. 4065-4083 ◽  
Author(s):  
W. T. Morgan ◽  
J. D. Allan ◽  
K. N. Bower ◽  
E. J. Highwood ◽  
D. Liu ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Chemical Composition ◽  
Ammonium Nitrate ◽  
Western Europe ◽  
Volatile Component ◽  
Organic Aerosol ◽  
Chemical Components ◽  
Airborne Measurements ◽  
North Western ◽  
Aerosol Chemical Composition

Abstract. The spatial distribution of aerosol chemical composition and the evolution of the Organic Aerosol (OA) fraction is investigated based upon airborne measurements of aerosol chemical composition in the planetary boundary layer across Europe. Sub-micron aerosol chemical composition was measured using a compact Time-of-Flight Aerosol Mass Spectrometer (cToF-AMS). A range of sampling conditions were evaluated, including relatively clean background conditions, polluted conditions in North-Western Europe and the near-field to far-field outflow from such conditions. Ammonium nitrate and OA were found to be the dominant chemical components of the sub-micron aerosol burden, with mass fractions ranging from 20–50% each. Ammonium nitrate was found to dominate in North-Western Europe during episodes of high pollution, reflecting the enhanced NOx and ammonia sources in this region. OA was ubiquitous across Europe and concentrations generally exceeded sulphate by 30–160%. A factor analysis of the OA burden was performed in order to probe the evolution across this large range of spatial and temporal scales. Two separate Oxygenated Organic Aerosol (OOA) components were identified; one representing an aged-OOA, termed Low Volatility-OOA and another representing fresher-OOA, termed Semi Volatile-OOA on the basis of their mass spectral similarity to previous studies. The factors derived from different flights were not chemically the same but rather reflect the range of OA composition sampled during a particular flight. Significant chemical processing of the OA was observed downwind of major sources in North-Western Europe, with the LV-OOA component becoming increasingly dominant as the distance from source and photochemical processing increased. The measurements suggest that the aging of OA can be viewed as a continuum, with a progression from a less oxidised, semi-volatile component to a highly oxidised, less-volatile component. Substantial amounts of pollution were observed far downwind of continental Europe, with OA and ammonium nitrate being the major constituents of the sub-micron aerosol burden. Such anthropogenically perturbed air masses can significantly perturb regional climate far downwind of major source regions.

scholarly journals Airborne measurements of the spatial distribution of aerosol chemical composition across Europe and evolution of the organic fraction

2009 ◽  
Vol 9 (6) ◽  
pp. 27215-27265 ◽  
Author(s):  
W. T. Morgan ◽  
J. D. Allan ◽  
K. N. Bower ◽  
E. J. Highwood ◽  
D. Liu ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Chemical Composition ◽  
Ammonium Nitrate ◽  
Western Europe ◽  
Volatile Component ◽  
Organic Aerosol ◽  
Chemical Components ◽  
Airborne Measurements ◽  
North Western ◽  
Aerosol Chemical Composition

Abstract. The spatial distribution of aerosol chemical composition and the evolution of the Organic Aerosol (OA) fraction is investigated based upon airborne measurements of aerosol chemical composition in the planetary boundary layer across Europe. Sub-micron aerosol chemical composition was measured using a compact Time-of-Flight Aerosol Mass Spectrometer (cToF-AMS). A range of sampling conditions were evaluated, including relatively clean background conditions, polluted conditions in North-Western Europe and the near-field to far-field outflow from such conditions. Ammonium nitrate and OA were found to be the dominant chemical components of the sub-micron aerosol burden, with mass fractions ranging from 20–50% each. Ammonium nitrate was found to dominate in North-Western Europe during episodes of high pollution, reflecting the enhanced NOx and ammonia sources in this region. OA was ubiquitous across Europe and concentrations generally exceeded sulphate by 50–100%. A factor analysis of the OA burden was performed in order to probe the evolution across this large range of spatial and temporal scales. Two separate Oxygenated Organic Aerosol (OOA) components were identified; one representing an aged-OOA, termed Low Volatility-OOA and another representing fresher-OOA, termed Semi Volatile-OOA on the basis of their mass spectral similarity to previous studies. The factors derived from different flights were not chemically the same but rather reflect the range of OA composition sampled during a particular flight. Significant chemical processing of the OA was observed downwind of major sources in North-Western Europe, with the LV-OOA component becoming increasingly dominant as the distance from source and photochemical processing increased. The measurements suggest that the aging of OA can be viewed as a continuum, with a progression from a less oxidised, semi-volatile component to a highly oxidised, less-volatile component. Substantial amounts of pollution were observed far downwind of continental Europe, with OA and ammonium nitrate being the major constituents of the sub-micron aerosol burden. Such anthropogenically perturbed air masses can significantly perturb regional climate far downwind of major source regions.

scholarly journals Granica państwa a spójność danych dla potrzeb analiz hydrologicznych. Studium przypadku dla zlewni Wiaru na pograniczu polsko-ukraińskim = A state border and the integrity of data for hydrological analysis. A case study of the River Wiar catchment on the Poland-Ukraine borderland

2020 ◽  
Vol 92 (1) ◽  
pp. 69-92
Author(s):  
Rafał Kroczak ◽  
Tomasz Bryndal ◽  
Szymon Biały ◽  
Olga Pylypovych ◽  
Yurij Andreychuk ◽  
...  
Keyword(s):  
Land Use ◽  
Spatial Distribution ◽  
Land Cover ◽  
Large Scale ◽  
Satellite Images ◽  
Chemical Components ◽  
Data Sets ◽  
Eu Directive ◽  
Land Cover Data

Hydrological investigations require the development of a geodatabase allowing for the calculation of physiographic catchment parameters, as well as the analysis of amounts of water resources and changes therein. Such a geodatabase usually consists of meteorological, hydrological and cartographic data. The present study offers a review of datasets that may be used for geodatabase development in the interests of hydrological research, in catchments located in the Polish-Ukrainian borderland. The catchment of the Wiar River – selected to serve as a case study – is in fact divided by the state border into two equal sub-catchments (395.5 km2 in Poland and 398.9 km2 in Ukraine).The results reveal disparities in the spatial distribution of stream and meteorological gauges. For the Polish part of the catchment datasets include many parameters (in accordance with EU Directive and Regulations) and the results from monitoring are available online as yearly reports. For the Ukrainian part, only chemical components are monitored, and these data are not made available publicly. Consistent data sets such as DEM can be obtained from globally available ASTER and SRTM models. Datasets, such as LiDAR, which are important for medium and large-scale analyses allowing for the development of high-resolution DEMs, do not exist. Use of TanDEM-X data is restricted for the Ukrainian territory. However, comparison between the SRTM and LiDAR models (for the Polish part) revealed that the SRTM model may be optimised to serve the whole area. Land-use and land-cover data (LULC) are important in many hydrological analyses. the authors propose using satellite images in the development of a comparable layer describing land cover of the whole catchment.

scholarly journals Chemical composition of aerosol in the atmospheric surface layer of the East Antarctica coastal zone

2016 ◽  
Vol 56 (2) ◽  
pp. 177-188 ◽  
Author(s):  
L. P. Golobokova ◽  
V. V. Polkin ◽  
N. A. Onischuk ◽  
O. I. Khuriganova ◽  
A. B. Tikhomirov ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Coastal Zone ◽  
Atmospheric Aerosols ◽  
Enrichment Factors ◽  
East Antarctica ◽  
Chemical Components ◽  
Aerosol Composition ◽  
Wide Range ◽  
Fresh Snow ◽  
The Antarctic

Chemical composition of aerosol in the ground layer of the coastal zone in East Antarctica is analyzed in the article. The aerosol samples were taken in 2006–2015 during seasonal works of the Russian Antarctic Expeditions (RAE), namely, these were 52nd–53rd, 55th, and 58th–60th expeditions. Samples were taken in the 200‑km band of the sea-shore zone along routes of the research vessels (REV) «Akademik Fedorov» and «Akademik Treshnikov» as well as on territories of the Russian stations Molodezhnaya and Mirny. Although the results obtained did show the wide range of the aerosol concentrations and a certain variability of their chemical composition, some common features of the variability were revealed. Thus, during the period from 2006 to 2014 a decrease of average values of the sums were noted. Spatially, a tendency of decreasing of the ion concentrations was found in the direction from the station Novolazarevskaya to the Molodezhnaya one, but the concentrations increased from the Molodezhnaya to the station Mirny. The sum of ions of the aerosol in the above mentioned coastal zone was, on the average, equal to 2.44 μg/m3, and it was larger than that on the territory of the Antarctic stations Molodezhnaya (0,29 μg/m3) and Mirny (0,50 ág / m3). The main part to the sum of the aerosol ions on the Antarctic stations was contributed by Na+, Ca2+, Cl−, SO4 2−. The main ions in aerosol composition in the coastal zone are ions Na+ and Cl−. The dominant contribution of the sea salt and SO4 2− can be traced in not only the composition of atmospheric aerosols, but also in the chemical composition of the fresh snow in the coastal areas of East Antarctica: at the Indian station Maitri, on the Larsemann Hills, and in a boring located in 55.3 km from the station Progress (K = 1.4÷6.1). It was noted that values of the coefficient of enrichment K of these ions decreases as someone moves from a shore to inland. Estimation of contributions of the continental and maritime factors to formation of the aerosol chemical composition revealed higher enrichment ratios for K+, Ca2+, SO4 2− (K = 3.6÷13.0). This reflects not only influence of the natural sources, but the intensity of human activities on the Antarctic continent as well. The elemental composition of solid aerosols was also analyzed. The largest concentrations were determined for Zn, Al and Fe. The ratio of concentration of the elements in both the soluble and insoluble phases of the aerosol showed that 84.1% of the total amount of the elements was contained in a water-insoluble state. Fractional relation between the element concentrations changed in different phases from 16 to 98%. High enrichment of the aerosol particles by Zn, Cu, Cr, Ba, Pb, Ni,Se, As, Cd (the enrichment factors = 27÷26 445) had been revealed. The content of dominant chemical components (Na+, Cl−, Zn, Fe), factors and coefficients of the element enrichment in the aerosols as well as in fresh snow of the coastal zone of East Antarctica are indicative of the identity of sources where their composition is formed.

Lithography below 100 nm

1983 ◽  
Vol 41 ◽  
pp. 96-99
Author(s):  
L. D. Jackel
Keyword(s):  
Spatial Distribution ◽  
Electron Beam ◽  
Electron Scattering ◽  
Electron Beam Lithography ◽  
Substrate Material ◽  
Local Electron ◽  
Electron Dose ◽  
Positive Resist ◽  
Exposure Process

Most production electron beam lithography systems can pattern minimum features a few tenths of a micron across. Linewidth in these systems is usually limited by the quality of the exposing beam and by electron scattering in the resist and substrate. By using a smaller spot along with exposure techniques that minimize scattering and its effects, laboratory e-beam lithography systems can now make features hundredths of a micron wide on standard substrate material. This talk will outline sane of these high- resolution e-beam lithography techniques.We first consider parameters of the exposure process that limit resolution in organic resists. For concreteness suppose that we have a “positive” resist in which exposing electrons break bonds in the resist molecules thus increasing the exposed resist's solubility in a developer. Ihe attainable resolution is obviously limited by the overall width of the exposing beam, but the spatial distribution of the beam intensity, the beam “profile” , also contributes to the resolution. Depending on the local electron dose, more or less resist bonds are broken resulting in slower or faster dissolution in the developer.

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