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51.
Late Bronze Age Copper Smelting Slags from Luserna (Trentino,Italy): Interpretation of the Metallurgical Process 下载免费PDF全文
In the Late Bronze Age, the extractive metallurgy of copper in north‐eastern Italy achieved a peak of technological efficiency and mass production, as evidenced by the substantial number of metallurgical sites and the large volume of slags resulting from smelting activities. In order to define the technological features of the Late Bronze Age metallurgical process, more than 20 slags from the smelting site of Luserna (Trentino, Italy) were fully analysed by means of optical microscopy, X‐ray powder diffraction, X‐ray fluorescence spectrometry and scanning electron microscopy. Three different slag types were identified based on mineralogical and chemico‐physical parameters, each being interpreted as the product of distinct metallurgical steps. A Cu‐smelting model is proposed accordingly. 相似文献
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Heather Ellis 《History & Technology》2016,32(2):120-136
AbstractIn September 1899, at the annual meeting of the British Association for the Advancement of Science (BAAS) in Dover, Guglielmo Marconi’s wireless telegraphy system was used to transmit messages across the English Channel (and across a national border) for the first time. This achievement represented a highly effective performance of scientific masculinity and constitutes a key turning point in an important struggle between competing interpretations of invention and innovation as masculine practices within British science. The British Association tended to favor a narrative of scientific research as a collectivist, international, gentlemanly-amateur pursuit, largely confined to the laboratory. Marconi, by contrast, explained the development of wireless telegraphy as the achievement of his own genius. Appealing not only to the established scientific elite but to a range of non-traditional audiences, and stressing the possibilities or ‘imagined uses’ of his technology even more so than his actual results, he succeeded in commanding unprecedented influence. 相似文献
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A. Gutirrez Garcia‐M. M. C. Savin N. Cantin S. Boudoumi P. Lapuente R. Chapoulie I. Pianet 《Archaeometry》2019,61(4):795-808
Identifying the origin of marble used in antiquity brings back to light details of the economic, social and political organization of classical societies, and characterizing in depth the chemistry of marble is key to discovering its provenance. Beyond X‐ray diffraction, which could reveal the presence of discriminant secondary crystalline phases and the quantification of accessory minerals combined with a multivariate analysis approach, solid‐state nuclear magnetic resonance (NMR) enables one to recognize the local structure arrangement of both crystalline and amorphous materials by looking at one or more selected atoms. In present paper targets the 13C nuclide, and thus the major component of marble, calcium carbonate. Whatever their geological origin, marbles 13C‐NMR spectra present only one resonance corresponding to the carboxyl function whose intensity and line width vary from one marble to another. If the variation of the NMR signal intensity observed is the result of great T1 variations (from 220 to 5300 s) and is linked to iron content, the line width reflects defects in the calcite crystal in which calcium has been replaced by another element such as magnesium, aluminium or strontium. The specific profile of the NMR signal has been used successfully to help determine the origin of some archaeological items. 相似文献
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The paper presents a brief overview and history of archaeometric research using instrumental neutron activation analysis at the Faculty of Chemistry of the University of Sofia. The archaeometric projects are listed and some of the results obtained in the investigations of glass, pottery and metals are described. 相似文献
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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
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Travertine was one of ancient Egypt's most popular ornamental stones. Upon prolonged exposure to sunlight, the rock's translucent brownish calcite is bleached to nearly white. Ultraviolet and gamma irradiation experiments were undertaken to investigate the source of the brownish colour and the process by which it fades. It was found that the coloration results from the activation of colour centres by natural radioactivity within the rock, and that these colour centres are deactivated by the ultraviolet component of sunlight. The results also demonstrate that the original brownish colour of sun‐bleached, travertine objects can be restored by artificial gamma irradiation. 相似文献
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I. K. BAILIFF 《Archaeometry》2007,49(4):827-851
Fired clay brick samples, obtained from a group of seven high‐status late‐medieval and post‐medieval buildings in England ranging in age from c. ad 1390 to 1740, were dated by the luminescence method using an optically stimulated luminescence (OSL) technique. The results obtained indicate that, when applied to quartz extracted from brick, the technique is capable of producing dates that are in consistently good agreement with independent dating evidence for the buildings. For six samples taken from a group of four dating ‘control’ buildings the mean difference between the central values of luminescence and assigned ages was 5 ± 10 years (SD, n = 6). The methodology used is appropriate for application to other standing buildings in other temporal and geographic regions, and may be used with confidence where conventional dating methods are less certain. The study also examines the luminescence characteristics of quartz and the characteristics of the lithogenic radionuclides in brick samples and identifies various aspects related to the assessment of experimental uncertainty in testing the reliability of the method. 相似文献