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Abstract

The list contains original papers by Polish authors or co-authors concerning Antarctic or sub-Antarctic plants. The list is supplemented by papers on bacteria and those on general indicators of the amount of plants (chlorophyll content and primary productivity). Antarctic investigations of Polish botanists were carried out mainly during the expeditions to Polish Antarctic Station "H. Arctowski" (King George Island, South Shetlands; 62° 09'S, 58° 28'W) founded 1977 as well as during Polish oceanic expeditions of the BIOMASS project (1981, 1983-1984, 1986-1987) and studies of the ice-edge zone (1988-1989) carried out in the Atlantic sector of Southern Ocean on board of the r/v "Profesor Siedlecki". All these expeditions were organized by the Department of Polar Research, Institute of Ecology, Polish Academy of Sciences headed by Prof. Dr. S. Rakusa-Suszczewski.
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Abstract

This paper is an overview of the application potential and design challenges of micro air vehicles (MAVs), defined as small enough to be practical for a single-person transport and use. Four types of MAVs are considered: 1) fixed-wing, 2) rotarywing, 3) ornithopters (bird-like flapping) and 4) entomopters (insect-like flapping). In particular, advantages of a propeller-driven delta wing configuration for type 1 are discussed. Some detail is also given for type 4, the least understood of the four, including a new concept of manoeuvre control for such MAVs. The paper concludes with a brief prognostic of the future of each MAV type.
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Abstract

Contamination of soil with heavy metals has become a worldwide environmental problem, and receives great attention. In this study, we aim to investigate soil pollution level affected by an industrial district nearby. The total amount of typical heavy metals in the soils (Hengyang Songmu Industrial Park, Hunan Province, China) was analyzed. In addition, the fraction analysis and laboratory simulation leaching via different pH rainwater was carried out to study the migration and transformation of heavy metals. The main results show that the contents of Cu, Zn, Pb, Cr and Cd in the samples were higher than the soil background values in Hunan Province. The heavy metals forms, analyzed by sequential extraction method, show that the proportion of the unstable form of Cd, Zn and Pb was more than 50%. Igeo values indicate that the heavy metal pollution degree of soil sample #5 at the investigated area is recorded in the order of Cd(6.42), Zn(2.28), Cu(1.82), Pb(1.63), and Cr(0.37). Cu, Zn, Pb, Cr and Cd in this area could pose a potential leaching risk to the environment which may affect the food chain and constitute a threat to human health. It would be necessary to take steps to stabilize and monitor the heavy metals in soil.
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