Coronal Hole Evolution During 1996–1999     

Belenko  Irina A. 《Solar physics》2001,199(1):23-35

Spatial and temporal distributions of coronal holes for the rising phase of the solar cycle during 1996–1999 are considered. Connections between the number of non-polar coronal holes on the solar disk and the Wolf number, the mean solar photospheric magnetic field, and the solar flux density at 2800 mHz are analyzed. Peculiarities of the photospheric magnetic field structure of the regions corresponding to coronal hole locations and comparison with `clear' ones are discussed.  相似文献   

Dew water collector for potable water in Ajaccio (Corsica Island, France)     

Marc Muselli  Daniel Beysens  Jacques Marcillat  Irina Milimouk  Torbjrn Nilsson  Alain Louche 《Atmospheric Research》2002,64(1-4)

We report on the development of an inexpensive radiative condenser for collecting atmospheric vapor. Based on the experience gained using a small working model in Grenoble (France), a prototype of 10×3 m² was established in Ajaccio (Corsica, France). The condensing surface is a rectangular foil made of TiO₂ and BaSO₄ microspheres embedded in polyethylene and has an angle of 30° with respect to horizontal. The hollow part of the device, thermally isolated, faces the direction of the dominant nocturnal wind. Dew measurements were correlated with meteorological data and compared to dew condensed on a horizontal polymethylmethacrylate (PMMA, Plexiglas) reference plate. The plate served as a reference standard unit and was located nearby. Between July 22, 2000 and November 11, 2001 (478 days), there were 145 dew days for the reference plate (30%), but 214 dew days for the condenser (45%). This yield corresponds to 767 l (3.6 l, on average, per dew day). The maximum yield in the period was 11.4 l/day. Dew mass can be fitted to a simple model that predicts dew production from simple meteorological data (temperature, humidity, wind velocity, cloud cover). Chemical analyses of the water collected from the plate were performed from October 16, 1999 to July 16, 2000 and from the condenser, from July 17, 2000 to March 17, 2001. The following parameters were investigated: suspended solids, pH, concentration of SO₄²⁻, Cl⁻, K⁺, Ca²⁺ ions. Only Cl⁻ and SO₄²⁻ ions were sometimes found significant. Wind direction analyses revealed that Cl⁻ is due to the sea spray and SO₄²⁻ to the combustion of fuel by an electrical plant located in the Ajaccio Gulf. Except for a weak acidity (average pH≈6) and high concentration of suspended solids, dew water fits the requirements for potable water in France with reference to the above ions.  相似文献   

Geometrical structure of shear wave surfaces near singularity directions in anisotropic media   总被引：1，自引：0，他引：1  

Vladimir Yu. Grechka  Irina R. Obolentseva 《Geophysical Journal International》1993,115(3):609-616

There are three types of surfaces which are used for studying wave propagation in anisotropic media: normal surfaces, slowness surfaces and wave surfaces. Normal surfaces and slowness surfaces have been researched in detail. Wave surfaces are the most complicated and comparatively poorly known compared with the other two. Areas of complicated geometrical structure of the wave surfaces are located in the vicinity of conical acoustic axes. There is an elliptical hole on the quick shear wave surface and complicated folds and cusps on the slow shear wave surface. Decomposition of the slow shear wave surface into smooth sheets is used for the study of its geometrical structure. Complexity of shear wave surfaces can be expressed by the number of waves corresponding to a fixed ray. An original approach to the calculation of wave normals depending on ray direction is presented.  相似文献   

Environment and paleoecology of a 12 ka mid-North American Younger Dryas forest chronicled in tree rings     

Irina P. Panyushkina  Steven W. Leavitt  Todd A. Thompson  Allan F. Schneider  Todd Lange 《Quaternary Research》2008,70(3):433-441

Until now, availability of wood from the Younger Dryas abrupt cooling event (YDE) in N. America ca. 12.9 to 11.6 ka has been insufficient to develop high-resolution chronologies for refining our understanding of YDE conditions. Here we present a multi-proxy tree-ring chronology (ring widths, “events” evidenced by microanatomy and macro features, stable isotopes) from a buried black spruce forest in the Great Lakes area (Liverpool East site), spanning 116 yr at ca. 12,000 cal yr BP. During this largely cold and wet period, the proxies convey a coherent and precise forest history including frost events, tilting, drowning and burial in estuarine sands as the Laurentide Ice Sheet deteriorated. In the middle of the period, a short mild interval appears to have launched the final and largest episode of tree recruitment. Ultimately the tops of the trees were sheared off after death, perhaps by wind-driven ice floes, culminating an interval of rising water and sediment deposition around the base of the trees. Although relative influences of the continental ice sheet and local effects from ancestral Lake Michigan are indeterminate, the tree-ring proxies provide important insight into environment and ecology of a N. American YDE boreal forest stand.  相似文献   

Barite from the Saf’yanovka VMS deposit (Central Urals) and Semenov-1 and Semenov-3 hydrothermal sulfide fields (Mid-Atlantic Ridge): a comparative analysis of formation conditions     

Nataliya P. Safina  Irina Yu. Melekestseva  Paolo Nimis  Nataliya N. Ankusheva  Anatoly M. Yuminov  Vasily A. Kotlyarov  Sergey A. Sadykov 《Mineralium Deposita》2016,51(4):491-507

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An empirical evaluation of three elevation change symbolization methods along routes in bicycle maps     

Annina Brügger  Sara Irina Fabrikant  Arzu Çöltekin 《制图学和地理信息科学》2017,44(5):436-451

ABSTRACT

Elevation change is critical for choosing a route when bicycling. We detail an empirical study in which we comparatively evaluated three linear symbolization types (color hue, color-coded arrows, and elevation profiles) to depict elevation change in bicycle maps for two common bicycle route planning tasks: relative height detection and slope identification. Participants performed most accurately with the color-coded arrows for relative height detection tasks, whereas symbolization did not significantly influence map-use performance for slope identification. Participants preferred the elevation profile, in spite of their lowest performance with this method overall. Our rare empirical findings offer much needed new insights into the function and appropriateness of common elevation symbolization methods, specifically to identify elevation change in bicycle route planning tasks in urban areas where map display real estate is already very limited.  相似文献   

Coronal Hole and Solar Global Magnetic Field Evolution in 1976 – 2012     

Irina A. Bilenko  Ksenia S. Tavastsherna 《Solar physics》2016,291(8):2329-2352

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A Global Perspective on Crustal Structure and Evolution based on A New Crustal Classification     

Irina M. ARTEMIEVA  Alexey SHULGIN 《《地质学报》英文版》2021,95(Z1):48-50

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1/3 of Antarctica is Not a Continent: Geophysical Evidence for West Antarctica as a Backarc System     

Irina M. ARTEMIEVA  Hans THYBO 《《地质学报》英文版》2021,95(Z1):51-54

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Thetys subduction and continental collision imaged by magnetic and gravity modeling     

Vahid Teknik  Abdolreza Ghods  Hans Thybo  Irina M. Artemieva 《《地质学报》英文版》2018,92(Z1):61-62

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