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861.
Blue glass trade beads from well-dated late seventeenth- to early twentieth-century sites and collections have been analysed non-destructively by instrumental neutron activation analysis. The beads display enough variations in their elemental contents to allow us to characterize the different chemistries. The implication of these results is that similar chemical analyses of blue beads from undated archaeological sites may be used to help date the sites, since each bead chemistry has a specific earliest period. 相似文献
862.
Fifty-three copper-based metal fragments, recovered from the Robitaille site in southcentral Ontario, were analysed by neutron activation to establish their chemical make-up and to sort them by their trace elemental chemistries. Three different European copper samples, one brassy copper and 48 brass samples with five different chemistries were found. As few as eight trading actions may account for all of the recovered European metal fragments. 相似文献
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Edward T. Linenthal 《The Historian; a journal of history》1995,57(4):687-694
Born in Boston, Massachusetts, in 1947, Linenthal earned his bachelor's degree in religious studies at Western Michigan University, his master's degree in divinity at the Pacific School of Religion, and his Ph.D. in religious studies at the University of California, Santa Barbara. He is Professor of Religion and American Culture at the University of Wisconsin, Oshkosh. His books include: Symbolic Defense: The Cultural Significance of the Strategic Defense Initiative (1989); Sacred Ground: Americans and their Battlefields (2nd edition, 1993); Preserving Memory: The Struggle to Create America's Holocaust Museum (1995); American Sacred Space (co-editor, 1995). He is writing a history of the A-Bomb controversy that will appear in a book to be published in 1996. Linenthal has often lectured about controversial historic sites for National Park Service staff. At the USS Arizona Memorial, Linenthal delivered a commemorative address on 7 December 1994, on the 53rd anniversary of the attack on Pearl Harbor. Linenthal and his wife, with their two sons, reside in Oshkosh, Wisconsin. Linenthal was the only historian to testify before the Senate Committee on Rules and Administration about the National Air and Space Museum's ill-fated exhibit, “The Last Act: The Atomic Bomb and the End of World War II.” What follows is Linenthal's Senate statement and comments he has written for The Historian. 相似文献
865.
Robert Steffens 《Berichte zur Wissenschaftsgeschichte》1995,18(4):259-260
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The possibility of lead isotope fractionation in ancient lead production is examined. Kinetic theory relating to isotopic fractionation in non-equilibrium evaporation is considered and the feasibility of the alteration of lead isotope abundance ratios in ore roasting and smelting is assessed. Previous experimental work is shown to have been inconclusive and conclusions are drawn on the need for further research to quantify the possible extent of fractionation in practice. 相似文献