Nickel vanadium tellurium oxide,NiV2Te2O10

Single crystals of nickel(II) divanadium(V) ditellurium(IV) decaoxide, NiV₂Te₂O₁₀, were synthesized via a transport reaction in sealed evacuated silica tubes. The compound crystallizes in the triclinic system (space group P). The Ni atoms are positioned in the 1c position on the inversion centre, while the V and Te atoms are in general positions 2i. The crystal structure is layered, the building units within a (010) layer being distorted VO₆ octahedra and NiO₆ octahedra. The metal–oxide layers are connected by distorted TeO₄E square pyramids (E being the 5s² lone electron pair of Te^IV) to form the framework. The structure contains corner‐sharing NiO₆ octahedra, corner‐ and edge‐sharing TeO₄E square pyramids, and corner‐ and edge‐sharing VO₆ octahedra. NiV₂Te₂O₁₀ is the first oxide containing all of the cations Ni^II, V^V and Te^IV.     

Frequency distribution, isotopic composition and physical characterization of plutonium-bearing particles from the Fig-Quince zone on Runit Island, Enewetak Atoll

Runit Island on Enewetak Atoll was very heavily impacted by the U.S. nuclear testing campaign in the northern Marshall Islands (1946–58). The primary source of contamination on Runit Island was the 1958 Quince safety test where a large quantity of device plutonium (Pu) was scattered over the area near the GZ. A second low-yield device was detonated on the same site 10 days later, further disturbing the soil and leaving behind a very heterogeneous pattern of contamination including milligram-size particles of plutonium. A limited cleanup of the Fig-Quince zone was carried out in 1979. During this period, the effectiveness of the cleanup operations was primarily evaluated on the basis of bulk soil concentration data with little consideration given to the heterogeneity and long-term material-, biological-, and environmental-specific impacts of residual high activity (hot) particle contamination. The aim of the present study was twofold; (i) to characterize the levels and distribution of residual contamination in the Fig-Quince zone, and (ii) to develop pertinent data on the frequency distribution, elemental and isotopic composition, and physico-chemical properties of hot particles isolated from surface soils from Fig-Quince with a view towards providing recommendations on the future management and possible cleanup of the site. Today, Runit Island remains under an administrative quarantine.     

Estimates for the L 2-Projection onto Continuous Finite Element Spaces in a Weighted L p -Norm

We consider the orthogonal L₂-projection P onto continuous finite element spaces. We prove estimates for P in a weighted L_p-norm and use these to prove corresponding approximation properties. AMS subject classification (2000) 65N60, 35K85     

Estimates of solutions of the H^p and BMOA corona problem

We prove new sharper estimates of solutions to the -corona problem in strictly pseudoconvex domains; in particular we show that the constant is independent of the number of generators. We also obtain sharper estimates for solutions to the BMOA corona problem. The proofs also lead to new results about the Taylor spectrum of analytic Toeplitz operators on and BMOA. Received: 28 August 1998 / in final form: 9 February 1999