die direktreduktion von eisenerzen zu eisenschwamm mittels erdgas wird iiberall dort verwendet wo einmal die notwendtigen rohstoffe und besonders der metallurgische koks zu wirtschaftlischen bedingungen fehlen. andereseirs wiederum miissen erdgasrerven in geniigenden mengen und qualitat zu verfugung stehen, urn die direktredution mit gutem wirkungsgrad durchfuhren zu konnen. in dieser arbeit wi...

1 Species 2000, Naturalis Biodiversity Center, Leiden, 2333 CR, Th e Netherlands 2 Royal Botanic Garden, Edinburgh, 20A Inverleith Row, Edinburgh EH3 5LR, Scotland, UK; and Royal Ontario Museum, Toronto 3 Missouri Botanical Garden, P.O. Box 299, St. Louis, Missouri 63166-0299, USA (address for correspondence: Botany Department, Th e Field Museum of Natural History, 1400 S. Lake Shore Drive, Chi...

HIGH altitude, long endurance (HALE) aircraft offer capabilities found nowhere else in the spectrum of machine flight, but their design and analysis offers unique challenges. From their observation altitude above 50,000 ft, HALE systems can relay telecommunication signals, perform intelligence, surveillance, and reconnaissance (ISR) functions covering large swaths of land for extended periods o...

We study topological von Neumann regularity and principal von Neumann regularity of Banach algebras. Our main objective is comparing these two types of Banach algebras and some other known Banach algebras with one another. In particular, we show that the class of topologically von Neumann regular Banach algebras contains all $C^*$-algebras, group algebras of compact abelian groups and ...

The deterioration of the income and employment position of unskilled workers in the OECD since the 1980s is a well-documented fact. The debate about the causes of this development is dominated by two competing hypotheses, "North-South Trade" ("globalisation") and technological progress. Several empirical methodologies have been used to identify and quantify the importance of these two explanati...