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M. Jeleńska A. Hasso-Agopsowicz M. Kądziałko-Hofmokl A. Sukhorada K. Bondar ZH. Matviishina 《Studia Geophysica et Geodaetica》2008,52(2):255-270
The paper concerns the complex study of pedogenic and magnetic characteristics of unpolluted soil profiles from Ukraine (3
profiles, of which two represent chernozem and one kastanozem) and Poland (1 profile of chernozem), all with loess parent
material. Two of the profiles were situated further south than the other two. The “southern” zone is characterized by lower
precipitation rate and higher annual temperatures than the “northern” zone. Depth variations of magnetic properties obtained
with various methods were compared with pedogenic characteristics. The common characteristic of all profiles is enhancement
of susceptibility in their upper parts related to the presence of superparamagnetic/ single-domain grains of maghemite/oxidized
magnetite of pedogenic origin. However, variations of magnetic characteristics measured down depth profiles differ between
profiles probably due to differences in climatic conditions and, perhaps, parent loess. 相似文献
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W. Jaeschke T. Salkowski J. P. Dierssen J. T. Trümbach U. Krischke A. Günther 《Journal of Atmospheric Chemistry》1999,34(3):291-319
During two measuring campaigns in early spring 1994 and 1995 (March/April) and one campaign in summer 1994, measurements of ozone, PAN, sulfur dioxide, nitric acid, and particulate nitrate, sulfate, and ammonium (only 1995) were recorded in the Arctic. Observations were made by aircraft at various sites in the eastern and western Arctic. Ozone concentrations showed a steady increase with altitude both in spring and summer. During five flights in springtime, low ozone events (LOEs) could be observed near the surface and up to altitudes of 2000 m. SO2 background concentrations, ranging from detection limit (0.5 nmol/m3) to 5 nmol/m3, were observed during both spring and summer. Distinct maxima up to 55 nmol/m3 in lower altitudes were only obtained in springtime. Concentrations of the organic nitrate PAN were within a similar range as those of the inorganic nitrate HNO3 during spring campaigns. In contrast, concentrations of particulate nitrate were one half an order of magnitude lower. HNO3 concentrations increased significantly with altitude. Evidently, HNO3 was intruded from the stratosphere into the troposphere. Sulfate concentrations ranged between 5 and 30 nmol/m3; ammonium concentrations were obtained within a range from 10 to 50 nmol/m3. 相似文献
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We describe software for an IBM compatible personal computer (PC) that we have developed and used to collect and analyze backscatter data from a multi-wavelength Mie-Rayleigh scanning lidar system. Both one and two-dimensional distributions of optical scattering coefficients are calculated from the lidar return signals and displayed in real time. Although we are using the software for analyzing marine aerosols, the modular nature of the software and data acquisition drivers make it straightforward to adapt the software to different systems, such as differential absorption lidar (DIAL) and oceanic lidars. We show examples of both horizontal and vertical Mie-Rayleigh lidar scans collected at the Makai Pier and Bellows Beach on the northeast side of the island of Oahu. 相似文献
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