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141.
Five experimental bloomery iron ore smelts were carried out in a reconstruction of an early medieval furnace of the Boécourt type (Switzerland). A part of the bloom from the most successful experiment was forged to a billet. Starting materials and products were weighed, described and chemically characterized (ICP-MS, LA-ICP-MS and WD-XRF). The calculation of the yield and mass balance based on the chemical analyses from the ore (optimum) and from the ore, furnace lining, slag and ash (applied) allow the determination and quantification of the materials involved in the process. This permits the interpretation of the quality of the experiments. The chemical characterization of metal produced from hematite ore from the Gonzen Mountains in Switzerland gives archaeologists the possibility to compare the metal of iron artefacts to metal from this mine. Finally a good agreement between experiments and archaeological reality can be shown.  相似文献   
142.
Three–dimensional (3D) ground–penetrating radar (GPR) represents an efficient high–resolution geophysical surveying method allowing to explore archaeological sites in a non–destructive manner. To effectively analyze large 3D GPR data sets, their combination with modern visualization techniques (e.g., 3D isoamplitude displays) has been acknowledged to facilitate interpretation beyond classical time–slice analysis. In this study, we focus on the application of data attributes (namely energy, coherency, and similarity), originally developed for petroleum reservoir related problems addressed by reflection seismology, to emphasize temporal and spatial variations within GPR data cubes. Based on two case studies, we illustrate the potential of such attribute based analyses towards a more comprehensive 3D GPR data interpretation.  相似文献   
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This paper presents the results of neutron activation analyses of pottery samples from four late sixth century bce sites in the Western Mediterranean: the Pointe Lequin 1A shipwreck, the Bourse site in Marseilles, the Greek colony of Emporion and the Cala Sant Vicenç shipwreck, with the goal of locating the production of a commonly found cup type, the so‐called ‘Ionian’ cup, type B2. The NAA results show three distinct compositional groups, although the location of production could not be determined with certainty. The results also show that submarine diagenesis of pottery samples does not necessarily render them incomparable with samples from terrestrial sites.  相似文献   
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Abstracts     
René Descartes is at the root of the modern world. Stephen Gaukroger explains why. Descartes sought to found philosophy on an investigation of the natural world rather than on theology and ethics. His task was complicated by the trial and condemnation of Galileo. He wished, as he says, to do nothing of which the Church could disapprove. In spite of this caveat he constructed over his lifetime an account of the world, from cosmology to psychology, which was fundamentally naturalistic, replacing the teleological thought of previous centuries with an unremitting mechanism. At the heart of his thought is mathematical physics. This determined his treatment of psychophysiology and the mind-body problem. In spite of 350 years of subsequent research the general idea of his neuropsychology remains surprisingly modern. He was one of the first to see humans as part of nature and his account of the relation of mind to brain is remarkably comprehensive and clear. Gaukroger’s book, although in this reviewer’s opinion open to criticism in some respects, provides a fascinating and in-depth account of the structure of Descartes’ thought.  相似文献   
147.
A multi-disciplinary palaeoecological approach on a sequence of dated archaeosediments was accomplished. The sediments derive from a multilayered prehistoric settlement mound in central Germany, representing the remnants of a prehistoric village. Based on the analysis of biological remains and geochemical/physical analysis of the settlement layers its environment was reconstructed. There is a trend to increasing anthropogenic activities and impact on the environment represented through a rise of indicators for productive surplus from the Early Neolithic (5300–4900 BC) until the Roman Times (400 AD). During the Early Neolithic, shifting flat settlements were situated in a locally opened landscape. The immediate surrounding of the floodplain was used by the settlers for their economic requirements (e.g. wood from the riparian forest). After a hiatus of ca. 1900 years, a multilayered settlement mount rose from Late Neolithic Times (3000 BC) to Roman Times. Since the Middle Bronze Age (approximately 1500 BC) the riparian forest was obviously replaced by agricultural fields and meadows and henceforward the hinterland used by the settlers probably grew in size. The continuing demand of wood was maintained by the acquisition of more distant sources. The onset of house constructions substituting wood by loam (wattle and daub) might be a possible societal response to this shortfall. This is reflected in the growing thickness and composition of the settlement layers, as well as in the archaeological record (e.g. tumbled wattle and daub house walls). The rising of the groundwater table and the start of severe floods of the adjacent river Helme during pre-Roman Iron Age (approx. 800–100 BC) might reflect a geomorphological response to the increased land use intensity at a regional scale.  相似文献   
148.
Deep sedimentary basins are complex systems that over long time scales may be affected by numerous interacting processes including groundwater flow, heat and mass transport, water–rock interactions, and mechanical loads induced by ice sheets. Understanding the interactions among these processes is important for the evaluation of the hydrodynamic and geochemical stability of geological CO2 disposal sites and is equally relevant to the safety evaluation of deep geologic repositories for nuclear waste. We present a reactive transport formulation coupled to thermo‐hydrodynamic and simplified mechanical processes. The formulation determines solution density and ion activities for ionic strengths ranging from freshwater to dense brines based on solution composition and simultaneously accounts for the hydro‐mechanical effects caused by long‐term surface loading during a glaciation cycle. The formulation was implemented into the existing MIN3P reactive transport code (MIN3P‐THCm) and was used to illustrate the processes occurring in a two‐dimensional cross section of a sedimentary basin subjected to a simplified glaciation scenario consisting of a single cycle of ice‐sheet advance and retreat over a time period of 32 500 years. Although the sedimentary basin simulation is illustrative in nature, it captures the key geological features of deep Paleozoic sedimentary basins in North America, including interbedded sandstones, shales, evaporites, and carbonates in the presence of dense brines. Simulated fluid pressures are shown to increase in low hydraulic conductivity units during ice‐sheet advance due to hydro‐mechanical coupling. During the period of deglaciation, Darcy velocities increase in the shallow aquifers and to a lesser extent in deeper high‐hydraulic conductivity units (e.g., sandstones) as a result of the infiltration of glacial meltwater below the warm‐based ice sheet. Dedolomitization is predicted to be the most widespread geochemical process, focused near the freshwater/brine interface. For the illustrative sedimentary basin, the results suggest a high degree of hydrodynamic and geochemical stability.  相似文献   
149.
The gold finds from Bernstorf, in the Freising district of Bavaria, were discovered in 1998, in the area of a Bronze Age settlement. First analyses with X‐ray fluorescence (XRF) revealed gold of an unusually high purity grade, which was explained by the use of cementation techniques. A newer analysis with laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) indicated an even higher purity. The analytical results were the starting point of an ongoing discussion. In this study, we re‐analysed 11 gold samples with synchrotron radiation–induced X‐ray fluorescence at the BAMline at BESSY. In a thorough analysis, different excitation and detection conditions were applied to confirm or disprove the previous results. It was shown that the purity of the gold from the specimen is higher than 99.9%. The main impurities are silver in a range between 20 and 200 μg g?1 and copper between 1 and 10 μg g?1. The results are in very good agreement with the LA–ICP–MS measurements and provide basic information for discussions about provenance, processing techniques or considerations of authenticity.  相似文献   
150.
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