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201.
W. Jack Rink H.P. Schwarcz H.K. Lee J. Rees‐Jones R. Rabinovich E. Hovers 《Geoarchaeology》2001,16(6):701-717
Electron spin resonance (ESR) dating and thermal ionization mass spectrometric 230Th/234U dating was conducted on six teeth from the prehistoric site of Amud Cave. By combining the ESR and 230Th/234U analyses, we obtained burial ages for teeth in various layers of the site. Layer B1/6–7, from which the Amud I Neanderthal skeleton was recovered, is dated to 53 ± 8 ka. Layer B2/8, which yielded other important human remains including the Amud 7 skeleton, gives a mean burial age of 61 ± 9 ka. One tooth from the lowest layer (B4) yielded a date of 70 ± 11 ka, but another tooth from this layer gave an 113 ± 18 ka. Despite this discrepancy, these ages agree with previously published TL ages on heated flints for the corresponding layers. This agreement between ESR on tooth enamel and TL on burned flint is also seen at all other sites studied with both methods in Israel. © 2001 John Wiley & Sons, Inc. 相似文献
202.
A new three-dimensional numerical model of coupled heat, moisture and air transfer in unsaturated soil is presented. In particular, the model accommodates moisture transfer in the form of liquid and vapour flow and heat transfer arising from conduction, convection and latent heat of vaporization. The bulk flow of dry air and the movement of air in a dissolved state are also included. The theoretical basis of the model, the finite element solution of the spatial terms and finite difference solution of the temporal terms are briefly presented. Attention is focused on the verification of the new numerical solution. This is achieved via comparisons with independent solutions of heat, moisture and air transfer in an unsaturated soil. The physical problem considered includes the highly non-linear hydraulic properties of sand. Thermal conductivity is also included as a function of soil moisture content. Excellent correlation of results is shown thus providing confidence in the new model. The new model is also applied to a number of test cases which illustrate the need for the development of a model which can fully include three-dimensional behaviour. In particular, three applications are presented each increasing in complexity. The first application illustrates three-dimensional heat transfer. This particular application is verified against existing commercial finite element software. Subsequent applications serve to illustrate how the coupled processes of heat moisture and air transfer combine to yield three-dimensional problems even within a simple geometric domain. Visualization of three-dimensional results is also addressed. © 1998 by John Wiley & Sons, Ltd. 相似文献
203.