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991.
When used for archaeological purposes, geophysical methods are often useful for the exploration, detection and mapping of archaeological remains. In the case of ancient metallurgical activities, slag accumulations form precious mineral records of these activities. Evaluating the volume of slag produced in such locations is an important issue, since it enables an estimate of the amount of metal produced in the smeltery. Unfortunately, slags themselves cannot be easily detected by DC electrical methods. Although they can be easily detected using magnetic techniques, these methods do not allow for an estimate of the quantity of slag, because magnetic fields do not conserve magnetic flux. In the present study we show that the Induced Polarization method (IP) is suited to the quantification of buried slags, provided the slag response has been suitably calibrated prior to the field measurements. The ability to quantify the quantity of slag is based on the quasi-linear relationship between the main IP parameter, i.e., the chargeability, and the slag concentration. This approach provides a new, non-invasive tool for the estimation of the volume of buried slag in palaeometallurgical sites.In this paper, an application of this technique for the site of Castel-Minier, Ariège, France, is presented.  相似文献   
992.
The stable isotopic analysis of archaeological and paleontological bones has become a common method to examine questions of ecology, climate, and physiology. As researchers addressing such questions incorporate museum collections in their studies, it is necessary to understand the isotopic effects of common preservation techniques utilized in such collections to ensure the preservation of original isotopic values. This study examines the effects of PVAc glue (polyvinyl acetate) applied in acetone solution and the subsequent removal of PVAc using various organic solvents on the δ13C and δ15N values of extracted bone collagen, the δ13C and δ18O values of carbonate in bone hydroxyapatite, and the δ18O values of phosphate in hydroxyapatite. The data demonstrate that isotopic values in the collagen and phosphate are unaffected by any combination of PVAc treatment and solvent application. The carbonates show little variation in δ13C values, but exhibit variable δ18O values upon exposure to the PVAc solution. It is here suggested that δ18O values from carbonates in PVAc-treated bones do not retain an original isotopic value and should not be included in future studies.  相似文献   
993.
Optically stimulated luminescence (OSL) measurements of individual quartz grains are reported for Middle Paleolithic (MP) or Middle Stone Age (MSA) deposits in La Grotte des Contrebandiers, Morocco. Single-grain measurements enable rejection of grains that may lead to under- or over-estimation of age due to malign luminescence properties or remobilisation of grains after burial. We identified the former using a range of experimental procedures and objective rejection criteria. Three post-depositional factors influenced the distribution pattern of equivalent dose (De) values for the remaining single grains: the disintegration of roof spall liberating unbleached, older grains into otherwise well-bleached sediments; the intrusion of a small number of younger grains from the overlying Upper Paleolithic deposits; and small-scale differences in the beta dose received by individual grains. Roof spall contamination was a significant problem, so we characterised the OSL signals and obtained De values for the calcareous sandstone in which the cave is formed, which allowed bedrock-derived grains in the MP/MSA deposits to be identified and rejected prior to age determination. We collected 31 samples from the MP/MSA deposits, and were able to calculate ages for 30 of them. These ages suggest that MP/MSA occupation of Contrebandiers was restricted to the interval between about 120 and 90 ka ago (Marine Isotope Stages 5d to 5b). Weighted mean OSL ages were obtained for samples associated with archaeologically sterile deposits at the base of the excavations (126 ± 9 ka), followed by two phases of the Moroccan Mousterian (122 ± 5 and 115 ± 3 ka), interspersed with archaeologically sterile deposits (112 ± 4 ka). The base and top of the Aterian were dated to 107 ± 4 and 96 ± 4 ka, respectively. Based on the grand weighted mean ages of 116 ± 3 and 103 ± 3 ka for the Moroccan Mousterian and Aterian at Contrebandiers, we suggest that these two industries may be separated by an occupation hiatus of up to 13 ± 3 ka at this site. Our single-grain OSL chronology confirms previous age estimates obtained for Contrebandiers and other sites in the vicinity, but are generally more precise and stratigraphically more coherent, due to the inherent advantages of measuring individual quartz grains and rejecting contaminant and other unsuitable grains before age determination.  相似文献   
994.
995.
996.
An intact Bell Beaker grave was discovered in February 1996 at Wellington Quarry, Marden, Herefordshire. The unmarked flat grave had no signs of a ditch or barrow, but may have been timber lined. It contained a tanged copper knife, a shale wristguard fragment, four barbed and tanged arrowheads, three arrowhead blanks, three flint knives, two triangular points or small daggers and four flint flakes. The adult male inhumation was accompanied by a complete, Maritime (AOO) Bell Beaker and may be dated to 2750–2500 BC (Late Neolithic). It belongs to Case's Group D. A notable feature of the grave goods is their different states of wear and completeness, varying from pristine to old, and including a fragment of a wristguard.  相似文献   
997.
We use trace element discrimination diagrams to provide a geochemical fingerprint for Tufo Lionato, the volcanic rock most commonly used in the ancient Roman dimension stone technique. Based on the comparison of their geochemical signatures, we identify different rock facies of Tufo Lionato employed since the fourth to third centuries and through the second century bce in the construction of the temples of the Area Sacra di Largo Argentina. These rock facies correspond to two previously identified building stones: Aniene Tuff and Monteverde Tuff, named after their supposed source areas located in the Aniene River Valley and in the homonymous locality of the Tiber River Valley, respectively. However, the results of our study demonstrate previous misidentification of these volcanic rocks in the different construction phases of Temple C, providing a revision of the dating system currently accepted for the diffusion of Tufo Lionato architecture. We show that the Aniene facies has been exploited since the end of the fourth century bce and that it was employed along with Tufo Giallo della Via Tiberina in the podium and staircase of Temple C, whereas observations at Largo Argentina suggest that the ‘Monteverde Tuff’ was only sporadically used in the early phases of the dimension stone construction technique.  相似文献   
998.
Isotopic, EPR and petrographic studies aimed at establishing the provenance of sculptural bigio antico are reported, including 18 possible quarry sites and 21 ancient sculptures. The results demonstrate that the Belevi quarry, north‐east of Ephesos, above the more famous white marble quarry, was the major source of this marble. Nineteen artefacts belong to Belevi, whereas the precise origin of the remaining two is unknown, but must probably be found within the same area. The peculiar distribution of δ13C values both for Belevi and artefacts was crucial for inferring the correct provenance, subsequently confirmed by additional analytical and petrographic data.  相似文献   
999.
1000.
As the sobriquet «Zweistein» suggests, within the theoretical physics community Wolfgang Pauli came to be regarded as second in eminence only to Albert Einstein. Over a period of thirty-five years, they interacted both intellectually and personally. This paper focuses on four interrelated topics of their discussions. 1) The theory of relativity: at the age of twenty, Pauli prepared the definitive survey of relativity, a survey which he revised near the end of his life and which remains invaluable to physicists and historians of physics. 2) Unified field theories: although initially sympathetic to Einstein's search for a unified theory of electromagnetism and gravitation, and having made important contributions to the subject, Pauli came to regard such efforts as fruitless. 3) Foundations of quantum mechanics: Pauli's negative evaluation of Einstein's program grew out of their sharply differing evaluations of the role that quantum mechanics would play in the future, development of theoretical physics. 4) Quantum gravity: Pauli recognized that, until the achievement of a successful reconciliation of quantum mechanics and general relativity — an achievement that still eludes us — Einstein's challenge to quantum mechanics could not be laid to rest.  相似文献   
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