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991.
992.
993.
Nathan Goodale Heather Otis William Andrefsky Jr. Ian Kuijt Bill Finlayson Ken Bart 《Journal of archaeological science》2010
In Southwest Asia, sickle blades first appear early in the sequence of the transition to agriculture. In the past, detailed qualitative research on silica bearing blade stone tools focus on the characterization of use-wear traces such as polish types and accrual rates. In this paper we approach the study of sickle blades slightly different, choosing to examine tool life-history by developing a method to quantitatively estimate harvesting intensity. The method centers on an experiment of cutting cereal stalks and measuring stone blade edge thickness under a scanning electron microscope as a proxy for cutting time. We end with regressing the experimental results to provide an estimation of how intensively archaeological sickle blades recovered from the site of Dhra’, Jordan were used for harvesting. The results, while preliminary, enable an initial interpretation of sickle blades as important tools with long use-life histories during the early Neolithic in the Southern Levant. 相似文献
994.
Demineralization of bone for collagen extraction is most commonly performed using dilute hydrochloric acid (HCl) despite the fact that little data exists on the effects of differing acid concentration or treatment time on the quantity and quality of collagen extracts and that hydrochloric acid is extremely effective at hydrolyzing peptide bonds. Data on yield, elemental composition, and isotopic signature from bone collagen obtained from multiple extractions performed on two large ancient human bone samples from prehistoric Puerto Rico indicate that there is no meaningful difference between acid treatments ranging from 0.05 to 0.2 M concentration and 24–120 h of treatment. As such, a shorter course of demineralization using more concentrated acid would appear to produce quality results in a shorter time. 相似文献
995.
996.
William D. Middleton Luis Barba Alessandra Pecci James H. Burton Agustin Ortiz Laura Salvini Roberto Rodriguez Suárez 《Journal of Archaeological Method and Theory》2010,17(3):183-208
The identification of chemical activity residues on archaeological surfaces requires the analysis of large numbers of samples,
which can be costly and time consuming. Researchers wishing to apply sediment chemistry often are confronted with a dilemma
of which technique to use and how to accommodate sediment chemistry into their budget. We propose an approach to the identification
of chemical activity residues in which semiquantitative spot tests, which are cheap, quick, and easy to apply, are employed
as an initial phase of analysis in order to leverage the results of more time-consuming and costly instrumental techniques.
Three examples that pair spot tests with gas chromatography-mass spectroscopy and inductively coupled plasma-optical emission
spectrometry analysis show that spot tests successfully identify areas of interest. This approach can save both time and research
funds. 相似文献
997.
We develop material to determine whether or not an arbitrary number is Löschian; the procedure embodied in the theorems achieves the desired result more swiftly than do previous solutions to this problem. The correspondence between a partition of the central place lattice and a quadratic form permits the rapid determination of the lattice coordinates of an arbitrary Löschian number and of the exact shape of a single fractal generator used to form an entire central place hierarchy associated with an arbitrary Löschian number. Central place hierarchies may be generated geometrically using a single shape applied initially to a hexagon and subsequently, scaled appropriately, to resultant polygons. Fractional dimensions of arbitrary central place hierarchies, measuring their “space-filling” characteristics, follow naturally from this general procedure. 相似文献
998.
William L. Morrow 《政策研究杂志》1989,18(1):213-219
Leslie Dunbar. 1988. The Common Interest: How Our Social Welfare Policies Don't Work and What We Can Do About Them
Charles Lockhart. 1989. Gaining Ground: Tailoring Social Programs to American Values 相似文献
Charles Lockhart. 1989. Gaining Ground: Tailoring Social Programs to American Values 相似文献
999.
Richard Melnick William John Shepard Dr .George Enteen 《The Historian; a journal of history》1993,56(1):197-199
1000.