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The McDonald Farm (also called the Anderson-Doosing Farm) in Catawba Valley, Virginia dates to 1789 and is registered with the National Register of Historic Places maintained by the National Park Service. According to written accounts, oral histories, and architectural analyses, the construction of four structures (a collapsed cabin, a standing cabin, a barn, and a smokehouse) at the farm likely occurred in the early to mid-19th century. To verify and refine the construction dates of the four structures, we absolutely dated the tree rings in logs used in their construction by comparing their ring patterns with a composite reference tree-ring chronology created from four regional locations. We used established graphical and statistical techniques used in dendrochronology to ensure that all tree rings were dated absolutely with 99.99% certainty. We found cutting dates for the collapsed cabin ranged from 1809 to 1810, making the likely builder Samuel Myers and not Joseph Anderson, who is currently given credit for its construction. The logs in the barn had cutting dates ranging from 1830 to 1831, confirming the 1830 construction date estimated by the historical documents and confirming the builder was Joseph Anderson. The logs from the standing cabin and smokehouse had cutting dates ranging from 1838 to 1840, refining the “mid-19th century construction” listed in the register nomination. Furthermore, the nomination gave credit of the construction of these latter two structures also to Joseph Anderson, but the builder was actually John Gish who owned the farm from 1837 to 1845. Our study demonstrates the benefit and reliability of using dendrochronology to verify and refine construction dates and ownership histories of historic structures in the Southeastern U.S.  相似文献   
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The City of Chicago and the inner suburbs grew much more slowly than the outer suburbs in recent decades. In the central county of the metropolitan area, commercial and industrial property is "classified," in that it is assessed at a higher ratio of market value than residential property. Classification is not used in the surrounding suburban counties. The empirical analysis finds evidence consistent with the notion that property tax classification contributes to differential rates of economic growth. High property tax rates lead to significantly slower growth rates for employment, commercial property, and industrial property.  相似文献   
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In this paper we explore the potential of non-destructive Infrared reflectance microspectroscopy (IRRMS) for the characterization of chert samples from 10 different geological outcrops in North America with emphasis on the Midcontinent. A principle objective of the project is to determine whether IRRMS analysis can provide a mineral-based signature for bedrock sources of chert artifacts. The technique utilizes a Bio-Rad Digilab FTS-40 Infrared spectroscope and microscope attachment that reflects an infrared beam off a chert specimen. Our findings indicate that spectral features from the molecules constituting minor and trace minerals in chert may provide sufficient characterization for chert sourcing.  相似文献   
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New field and laboratory work has been carried out on two vitrified forts, Rhubh Aird Ghamhsgail near Arisaig and The Torr near Acharacle. Fieldwork confirms that both are constructed from rubble largely comprising local psammitic Moine Supergroup rocks and that their walls are relatively well preserved with large portions of vitrified material remain, particularly at The Torr, where remnants of up to four courses of stone facing occur. The preserved wall fills comprise mostly psammitic rubble set in a dark brown, vesicular, glassy to aphanitic matrix that in many places preserves evidence of downward flow. Conventionally, vitrification is explained through combustion of timber interlacing within the walls leading to melting that has been modelled in the granite system. However, considering Iron Age smelting technology, this leads to problems in obtaining high temperatures (≥1000 °C) over tens of metres of wall length. Geochemical analysis of the vitrification indicates that modelling the melting within the granite system is incapable of providing a partial melt matching the composition of vitrification. At The Torr, pelite fragments have been found near the base of the wall where partial melt occurs as black bubbles. In these fragments it appears that micas (largely biotite) have formed the melt via the reaction biotite + quartz = sanidine + orthopyroxene + liquid which takes place at temperatures c. 850 °C. Quench crystals in the melt include orthopyroxene, plagioclase, spinels, ilmenite, magnetite, anatase and apatite confirming that it was not a granite melt. These melted fragments are found next to material with biotite that, superficially, appears unmelted, suggesting that some of the heating took place perhaps away from the edifice and unmelted residue was utilised as part of the rubble fill, suggesting that in situ partial melting of the rubble is unlikely. However, in other parts of the edifice heat affected, yet unmelted, fragments are dominant. The new evidence indicates that vitrification occurred at lower temperatures than previously modelled and thus the melts could have been achieved more easily than previously thought.  相似文献   
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We recognize a new style of Mississippian-period art in the North American Southeast, calling it Holly Bluff. It is a two-dimensional style of representational art that appears solely on containers: marine shell cups and ceramic vessels. Iconographically, the style focuses on the depiction of zoomorphic supernatural powers of the Beneath World. Seriating the known corpus of images allows us to characterize three successive style phases, Holly Bluff I, II, and III. Using limited data, we source the style to the northern portion of the lower Mississippi Valley.  相似文献   
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On sectioning six of eight externally well-preserved teeth taken from four skeletons from Medieval Chichester they displayed a superficial similarity to teeth described in the forensic literature as ‘pink teeth’. This article reviews the occurrence of ‘pink teeth’ in forensic specimens and describes the teeth from Chichester using a variety of analytical techniques. We conclude that, despite the similarities, the pink coloration in the archaeological specimens has a different cause from the forensic samples, and that in archaeological contexts the pinkness is probably related to post-mortem change brought about by saprophytic fungi. However, the exact cause of the coloration remains unexplained. We discuss briefly the implications of this observation for dental ageing techniques and other studies of archaeological teeth.  相似文献   
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