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11.
Abstract

In recent years systematic archeochemical investigations in the medieval town of Trondheim have provided the heritage management authorities with a rich and complex set of data concerning the status and condition of the cultural deposits in the anthropogenic material. The collected data raises important questions for the long-time management of in situ preservation for archaeological material in non-saturated zones. In this paper we present the standardized scientific methods used in these archeochemical investiga- tions. We examine the results from several sites in the town and discuss the challenges facing modern heritage management in its efforts to protect a complex body of archaeological material in the non-saturated zone. We show that sediments with a thickness of 1–2 m have low levels of moisture and organic matter, and most of the inorganic parameters analysed are found in oxidized form with low preservations. The 2–3 m thick anthropogenic sediments showed better preservation conditions.  相似文献   
12.
We have investigated change in subsistence during the transition to agriculture in the site of Jiahu, Henan Province, China, using stable isotopic analysis of collagen and apatite in human bones. Millet agriculture is well documented at drier high latitudes of the Yellow River Valley, while rice agriculture predominated at wetter lower latitudes of the Yangtze Valley region. The early Neolithic site of Jiahu lies near the boundary between the drier north and wetter south. Archaeobotanical evidence shows that rice was a significant component of diet at Jiahu, but its δ13C value is similar to that of other foods, and therefore cannot be conclusively identified by carbon isotope analysis. Foxtail and broomcorn millets are the only C4 crops known for the Chinese Neolithic. Because of their high δ13C values, their consumption can be evaluated by stable carbon isotope analysis of human bone. Collagen reflects mainly the δ13C value of dietary protein, and apatite accurately records that of the whole diet. Isotopic analysis of 15 well-preserved samples from three periods shows that collagen δ13C values were very low for almost all individuals, suggesting C3-based foods dominated their diets. However, apatite carbonate δ13C values and δ13C spacing between collagen and apatite (Δ13Cap-co) indicate that millet may have been a minor component of the diet in this region. Individuals, who consumed the smallest amounts of animal protein, as indicated by low δ15N, generally had the highest apatite δ13C values. Archaeobotanical evidence for millet at Jiahu is needed to support this interpretation.  相似文献   
13.
Isaac Newton, like many of his contemporaries, appears to have distinguished between the practice of divinity, founded on divine revelation, and philosophical considerations of God derived from the study of nature. This article evaluates these distinct modes of divine discourse through a close reading of the chymical content of Newton’s optical writings and his correspondence with Thomas Burnet regarding Genesis. Newton’s chymical exploration of divine activity in the natural world in Query 31 to the Opticks (1704) seems independent from Scripture in its physico-theological demonstration of God from natural phenomena and its divine metaphysical reliance on a priori concepts of God to establish principles of nature. Nonetheless, the sensorium analogy by which he explored divine agency in nature drew directly from the biblical doctrine of the imago Dei. Moreover, Newton used his chymical understanding of nature to access the natural-philosophical realities behind the accommodated words of the Mosaic creation account.  相似文献   
14.
Bone chemistry paleodietary studies are emerging as important research areas in archaeology, biological anthropology, and paleontology. With appropriate controls, the inorganic and organic chemical composition of bones and teeth can provide information about past diet and habitat use. Chemical signatures are used to address individual dietary variability in early hominid fossils, paleontological remains, and more recent human and faunal populations.  相似文献   
15.
A collection of 30 ceramic samples, 16 of coarse wares and 14 of fine painted wares, have been investigated by optical microscopy, scanning electron microscopy, inductively coupled plasma optical emission spectrometry, inductively coupled plasma mass spectrometry and neutron activation analysis. Further samples of clayey sediments, both locally outcropping and found within the settling tank, have been submitted to the same analytical techniques for comparison with the ceramic collection. The results demonstrated that local clayey sediments were used as received for the production of coarse wares. The same raw materials were sieved and/or refined by decantation for the production of fine painted wares, which, in fact, provided results that were perfectly comparable with those for the clayey raw materials found within the settling tank. The Faragola productions were distinguished from the neighbouring Apulian productions according to petrographic features (the presence of leucite‐bearing volcanic rocks and Mn‐rich wads) and their bulk chemical composition.  相似文献   
16.
罗玉海 《神州》2011,(9X):219-220
学生对生活中的一些化学现象提出置疑,利用自己已有的实验能力和认知能力,运用实验手段,印证结论或探究未知。使学生真正成为化学实验的主体和中心,使学生实现自主、体验、参与和合作的学习方式并达到掌握知识和培养创新能力的目的。  相似文献   
17.
Abstract

From 1865 to about 1910 studies of the chemistry of the brain were afflicted by the hypothesis that cerebral lipid matter consisted of a giant molecule from which all the simpler lipids were derived as breakdown products. In successive periods the main proponents of this ‘protagon’ theory were Oscar Liebreich, Arthur Gamgee and William Cramer. The theory was disproved by the careful and detailed studies of JLW Thudichum whose work on the brain was described in many papers, government reports, and two outstanding monographs. The controversy involved rough moments, generated by both sides, but by 1910, a few years after his death, Thudichum was fully vindicated in his opposition to the protagon concept and his classification of brain lipids became the accepted standard for biochemistry as a whole.  相似文献   
18.
Abstract

In situ preservation is a core strategy for the conservation and management of waterlogged remains at wetland sites. Inorganic and organic remains can, however, quickly become degraded, or lost entirely, as a result of chemical or hydrological changes. Monitoring is therefore crucial in identifying baseline data for a site, the extent of spatial and or temporal variability, and in evaluating the potential impacts of these variables on current and future in situ preservation potential.

Since August 2009, monthly monitoring has taken place at the internationally important Iron Age site of Glastonbury Lake Village in the Somerset Levels, UK. A spatial, stratigraphic, and analytical approach to the analysis of sediment horizons and monitoring of groundwater chemistry, redox potential, water table depth and soil moisture (using TDR) was used to characterize the site.

Significant spatial and temporal variability has been identified, with results from water-table monitoring and some initial chemical analysis from Glastonbury presented here. It appears that during dry periods parts of this site are at risk from desiccation. Analysis of the chemical data, in addition to integrating the results from the other parameters, is ongoing, with the aim of clarifying the risk to the entire site.  相似文献   
19.
What's in a bone? Recent advances in archaeological bone chemistry   总被引:2,自引:0,他引:2  
This paper focuses on advances in archaeological bone chemistry since 1989. At that time studies generally shifted from development and application of techniques in bone chemistry to more experimental approaches. In stable isotope studies, controlled feeding experiments have been carried out to determine the routing of various dietary components into bone tissues. Biological apatite has been added to collagen as a tissue of study for stable carbon isotope analysis, providing the ability to study much older remains. Other elements have been added such as hydrogen for the study of paleoclimate and oxygen and strontium isotopes to study life history. Trace element studies have focused on methods of detecting and controlling for diagenesis, and barium has been added to the list of useful dietary indicators. Attempts to extract DNA from archaeological bone have been successful, however, this field is still in its early stages in terms of applications to understanding prehistoric biological relationships.  相似文献   
20.
Inferences about settlement structure play an important role in explanations of social and political change in Late Prehistoric eastern North America, but ethical and logistical challenges posed by extensive horizontal excavations mean that archaeologists must develop low cost, minimally invasive methods for investigating key properties of village structure. There are two important components of most villages in the region: 1) the peripheral distribution of middens; and 2) the size and location of formal communal spaces or plazas, each of which leaves traces in soil chemistry. In shallowly buried, plowed village sites where artifacts have been physically displaced, the chemical signature of middens may be more resistant to disturbance and provide an enduring signature of ancient settlement structure. We conducted a systematic soil phosphorus survey at the Reinhardt Site (33PI880) in central Ohio, the primary occupation of which occurred during the Late Prehistoric Period (ca. AD 1200-1450), to test for the presence and approximate size of a central plaza and the shape and distribution of peripheral midden deposits. Soil samples from the modern plowzone (N = 131) were analyzed for Mehlich II extractable phosphorus using molybdate colorimetry. The interpolated phosphorus distributions indicate a clear ring midden approximately 90 m across with an internal plaza that is roughly 30 m × 40 m. Artifact distributions from a shovel test pit survey and interpolations of plowzone magnetic susceptibility measurements identify the location of the village but are ambiguous with regards to village size and do not clearly distinguish the central plaza. Our results suggest that systematic surveys of soil phosphorus are a rapid, minimally invasive, and inexpensive method for generating data on the size and shape of villages and their plazas.  相似文献   
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