Structural Incorporation of Selenium into Pyrite and Mackinawite

Selenium has a radiotoxic potential as 79Se radionuclide if discharged from a high-level nuclear waste repository into the biosphere. We performed three different syntheses of selenium doted pyrite and examined the amount of incorporated Se as well as the structural bonding. The incorporated amount of Se is very high (>98%). The structural substitution of Se by S occurs only for high supersaturated solutions. Under anoxic and acidic conditions, the incorporation of Se(0) is more likely

Detectability of strange matter in heavy ion experiments

We discuss the properties of two distinct forms of hypothetical strange matter, small lumps of strange quark matter (strangelets) and of hyperon matter (metastable exotic multihypernuclear objects: MEMOs), with special empha- sis on their relevance for present and future heavy ion experiments. The masses of small strangelets up to AB = 40 are calculated using the MIT bag model with shell mode filling for various bag parameters. The strangelets are checked for possible strong and weak hadronic decays, also taking into account multiple hadron decays. It is found that strangelets which are stable against strong decay are most likely highly negative charged, contrary to previous findings. Strangelets can be stable against weak hadronic decay but their masses and charges are still rather high. This has serious impact on the present high sensitivity searches in heavy ion experiments at the AGS and CERN facilities. On the other hand, highly charged MEMOs are predicted on the basis of an extended relativistic mean field model. Those objects could be detected in future experiments searching for short lived, rare composites. It is demonstrated that future experiments can be sensitive to a much wider variety of strangelets

Geopolitics of the Kaliningrad Exclave and Enclave: Russian and EU Perspectives

Two U.S. political geographers examine a range of geopolitical issues associated with the shifting sovereignty of Russia\u27s Kaliningrad Oblast (a part of the former German province of East Prussia) during the 20th century, as well as the region\u27s evolving geopolitical status as a consequence of the European Union\u27s enlargement to embrace Poland and Lithuania. They argue that Kaliningrad today can be considered a double borderland, situated simultaneously on the European Union\u27s border with Russia as well as physically separated from Russia, its home country, by the surrounding land boundaries of EU states. Although technically neither an exclave nor an enclave, they posit that in many ways it resembles both, and as such presents a unique set of problems for economic development and interstate relations