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41.
Desenfant Fabrice Petrovský Eduard Rochette Pierre 《Water, air, and soil pollution》2004,152(1-4):297-312
Industrial pollution is one of the most important environmentalthreats, with serious consequences for the future. Thus, its detailed study is of great importance. Apart from expensive andtime-consuming chemical methods, several rapid and cheap proxymethods have been developed recently, one of them being based on rock-magnetic parameters. In the present paper we examine the use of rock-magnetic methods designed to assess the degree of pollution of recent stream sediments taken from the Arc river (Provence, France). The aim was to identify industrially-derived magnetic particles and to link this `magnetic pollution' to concentrations of heavy metals. Geological basements allow the easy determination of magnetic particles of industrial origin. Our results clearly demonstrate that magnetic anomalies, observed in the stream sediments along the river, can be explained by human activities, as they correlate well with concentrations of lead, zinc, iron and chromium. 相似文献
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Diffusion of atoms in a crystalline lattice is a thermally activated process that can be strongly accelerated by defects such as grain boundaries or dislocations. When carried by dislocations, this elemental mechanism is known as "pipe diffusion." Pipe diffusion has been used to explain abnormal diffusion, Cottrell atmospheres, and dislocation-precipitate interactions during creep, although this rests more on conjecture than on direct demonstration. The motion of dislocations between silicon nanoprecipitates in an aluminum thin film was recently observed and controlled via in situ transmission electron microscopy. We observed the pipe diffusion phenomenon and measured the diffusivity along a single dislocation line. It is found that dislocations accelerate the diffusion of impurities by almost three orders of magnitude as compared with bulk diffusion. 相似文献
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Jordi Bartolomé Josefina Plaixats Jesús Piedrafita Marta Fina Eduard Adrobau Aida Aixàs Marina Bonet Jordi Grau Lluis Polo 《Strength and Conditioning Journal》2011,64(3):319-324
The dietary composition of the semiferal cattle population in the Alberes Natural Park in northeastern Spain was determined four times per year, from June 2002 to February 2004, by microhistological analysis of a total of 120 fecal samples. Woody species, mainly the Quercus and Erica genera, formed the bulk of the diet, reaching 89% of it in winter. However, in spring and summer, the proportion of woody and herbaceous species varied between samples, depending on the habitat where they were collected. The forest samples contained 67% woody species in summer, whereas grassland samples only contained 44%. The results showed that the Alberes cattle population grazed actively in Mediterranean forests and consumed a high proportion of the most combustible species, such as the Erica genus (39% of the epidermal fragments in winter samples). Even when grassland habitat was utilized, in spring and summer, one-third of the diet was from woody species. Some bovines, such as the Alberes cattle breed, can therefore survive year-round in a forest habitat with little forage supplementation, and the consumption of a predominantly woody diet would be expected to reduce forest fire hazards. 相似文献
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Eduard Langerfeld 《Potato Research》1973,16(4):290-292
Zusammenfassung Kartoffelknollen von Düngungsparzellen mit unterschiedlichen N?hrstoffgaben wurden nach künstlicher Infektion mitFusarium coeruleum auf ihre F?uleanf?lligkeit geprüft. Die gr?sste F?uleausbreitung zeigte sich bei Knollen von der ungedüngten Parzelle, gefolgt
von der NPK-Variante. Einen deutlich hemmenden Einfluss hatte Calzium, sowohl mit als auch ohne NPK-Düngung gegeben. Ebenso
wirkten auch die Elemente Mg, Mn, Cu und B befallssenkend. 相似文献
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Gerald Dirnberger Angela-Elisabeth Kumer Eduard Schnur Hubert Sterba 《Annals of Forest Science》2017,74(1):8