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1.
The flame atomic absorption spectroscopy method of analysis of trace elements (Mn, Sr, and Cu) in a mammoth's bone and the method of estimation of the data using regression analysis are described. The concentration fields of the single elements in a cross-section through the bone are well described by a fourth degree polynomial. The minimum values and their coordinates have been determined. A method of determination of the original concentrations of trace elements in fossil bones is described further. The approximating features of the regression exponential equations and of the diffusion functions of various shapes were determined and a method for calculating the concentrations and diffusion properties of the bones once deposited in the soil is suggested. The original trace element concentration can be estimated by extrapolation of a suitable exponential or diffusion function.  相似文献   
2.
The levels of ten elements (phosphorus, calcium, magnesium, strontium, barium, potassium, sodium, zinc, iron, and aluminium) have been measured in the femurs and humeri of laboratory rats grown on test diets as a model for palaeodietary studies of excavated human skeletons. High levels of dietary fibre correlate with lower Ca and higher Sr and Ba in the bone. High values of the dietary Sr/Ca ratio correlate with high Sr levels in the bone. High levels of dietary protein correlate with lower Sr and higher Zn. High values of the ratio Ba/Ca and lower levels of Fe correlate with higher levels of Ba. Because bone levels typically are controlled by several dietary components, variation of the levels of a given element in the diet does not necessarily translate into analogous variations in bone. Only K and Fe in bone correlate highly with their levels in diet. The failure of bone Sr, Ba, and Zn to correlate positively with dietary levels is fully explicable in terms of their interdependence on other dietary components, such as Ca, P, Fe, protein, and fibre.  相似文献   
3.
This paper describes the archaeometric research conducted at the SLOWPOKE Reactor Facility of the University of Toronto (SLOWPOKE‐Toronto) during its existence from 1971 to 1998. The contributions to student teaching and research are described, and the total contribution of the facility to studies of an eclectic assortment of ancient and historic materials is addressed.  相似文献   
4.
Archaeological bones, found close to Mexico City (Tlatelcomila), with alterations due to probable thermal exposure attributed to a possible case of cannibalism, have been characterized by XRD, SAXS and SEM. It is shown how these non‐destructive techniques, which are not conventionally used in archaeological research, may provide useful information. The deterioration degree of the bone structure is quantified through parameters such as gyration radius or fractal dimension. As some of the reported modifications could be attributed to diagenesis, a discussion is presented in terms of bone crystallinity and ionic exchange. Furthermore, the hydroxyapatite crystallite size increased depending on colour: this feature is not explained by diagenesis—it can only be attributed to temperature. We conclude that the samples were thermally treated. Indeed, thermal treatment alters the structure and morphology of bone at a very fine level (microscopic and nanometric), while morphology follows the structural modifications. It is determined that the studied human bones were treated at three different temperatures close to 100, 250 and 600°C. Therefore, they were either boiled (barbacoa) or grilled.  相似文献   
5.
To improve the methods used to study prehistoric cremation rituals, cremation urns from the Danish Late Bronze Age were examined using computed tomography and computed radiography (digital X‐ray). During micro‐excavation, the digital images were used as a registration tool. Our results suggest that osteological ageing and sexing are more accurate when combining CT images with excavated remains. Digital volume rendering further enables a compromised estimation of the original cremation weight. Micro‐excavation is clearly a primary cause of bone fragmentation. Cremated remains affected by lower cremation intensity show markedly poorer preservation and recovery than do white calcined fragments. Thus post‐excavation estimations of cremation intensity are systematically biased.  相似文献   
6.
The graphical and linguistic interpretation of the first six Etruscan numerals has long been confronted with the ambiguous assignment of the words huth and sa to either 4 or 6. Here, we show how the systematic combinatorial analysis of the numerals appearing on ancient southern Etrurian dice dated from the eighth to the third centuries bc , together with the careful comparison of the results with the only two existing dice carrying the alphabetical translations of the numerals conserved at the Bibliothèque Nationale de France, Paris, finally allows unambiguous mathematical resolution of the linguistic riddle, allowing the firm attribution of the numeral 6 to the graphical value huth and 4 to sa. Combinatorial analysis of the numerals distribution on the six faces of the die shows that only two of the 15 possible numerical combinations were actually in use in southern Etruria, and that during the fifth century bc there was a marked shift from the typical (1–2, 3–4, 5–6) combination used in the early seventh‐ to fifth‐century bc dice to the (1–6, 2–5, 3–4) combination used at later times and still largely adopted today. The largest body of archaeometric data on dice specimens from Etruria is presented, based on macroscopic examination, X‐ray diffraction, DRIFT spectroscopy and density measurements.  相似文献   
7.
This paper presents a quantification method for archaeological molluscs using fragmentation categories. By employing the data from nine prehistoric sites (13 000 to 5000 bp ; 15 700 to 5700 cal bp ) in Cantabrian Spain (northern Spain), it has been shown that traditional methods, based on one or two anatomical elements, systematically produce a loss in the minimum number of individuals (MNI) that is sometimes significant. This paper also proposes using fragmentation categories in the calculation of the fragmentation index. In addition, based on these indices, a reflection is made on the difficulty involved in associating the amount of fragmentation of the shells with the taphonomic processes that have occurred at the archaeological sites, especially in discerning which agents have caused the fragmentation.  相似文献   
8.
Archaeological bone undergoes alterations after burial (diagenesis) that constitute a problem for the survival of archaeological information. A common method to assess this alteration is Fourier transform infrared spectrometry (FTIR). However, the commonly applied method (FTIR–KBr) is destructive and sample preparation may influence the results. This paper tests the suitability of FTIR attenuated total reflection (FTIR–ATR), a method not commonly used to investigate bone diagenesis. FTIR–ATR requires less sample preparation and can be non‐destructive, allowing analysis of bone cross‐sections. Modern and archaeological bones were analysed using both methods and different sample preparation methods were tested. The results show that FTIR–ATR has advantages for the rapid assessment of bone diagenesis.  相似文献   
9.
Archaeological bones of varying preservation have been treated with 0·1 M acetic acid in order to investigate the effect on structural and chemical alterations caused by diagenesis. Acetic acid is commonly used as a “cleaning agent” for removing diagenetic carbonate from bone and enamel, in an attempt to recover original, biogenic signals for use in dietary and14C dating studies.Diagenetic parameters were measured before and after treatment on a range of archaeological bones with good and bad preservation. Histological preservation defined the behaviour of the correlating parameters, where correlation coefficients between carbonate content and crystallinity, microporosity and macroporosity increased significantly after treatment. For histologically well preserved material, acetic acid is effective at returning carbonate content to around that of modern bone. Where bone is extensively damaged by micro-organisms, “loose” diagenetic material can be removed, but a fraction largely composed of hypermineralized bioapatite remains, which, we believe, cannot be reliably used to obtain accurate biological signals.  相似文献   
10.
Abstract

The background to the Icelandic and Greenlandic sites under investigation is outlined and prior work on the Norse economies of the two islands is discussed. The importance of fat in the diet and the use of levels of bone marrow and grease exploitation as an indicator of subsistence stress are explained. The methodology for establishing levels of bone fat exploitation is outlined. This methodology involves the detailed study of fragmentation levels of different types of bone, study of bone fracture types and many other taphonomic indicators. The results of the study are described and discussed. On Greenland, the Norse inhabitants exploited almost all available fat from land mammal bones, leaving only the ribs. It is argued that this indicates a severe level of subsistence stress amongst the Greenlanders that is most likely related to a seasonal dearth in resources. On Iceland, whilst a certain amount of bone marrow is almost certainly exploited, the settlers appear to almost totally ignore the potential to exploit bone grease. This is likely to be indicative of a much more healthy subsistence economy than on Greenland. These results are discussed in relation to differing climate, availability of good soil, fishing practices and seasonal rounds.  相似文献   
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