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941.
Measurements on cranial and pectoral girdle bones of 56 museum specimens of modern sturgeon (Acipenser sturio and A. oxyrinchus) were used for the establishment of regression equations allowing back‐calculation of size from isolated sturgeon remains. Different curve fittings (power, linear, logarithmic and exponential fit) were modeled to retain the most accurate regression. These were then applied to archaeological sturgeon remains (A. sturio/A. oxyrinchus) from Vlaardingen, a Dutch late Neolithic settlement. The back‐calculated lengths obtained on the archaeological remains all stayed within the known size ranges of the two species and allowed making inferences on the possible place of capture of the fish. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
942.
X.‐L. Chen S.‐M. Hu Y.‐W. Hu W.‐L. Wang Y.‐Y. Ma P. Lü C.‐S. Wang 《International Journal of Osteoarchaeology》2016,26(1):42-52
Although a patchwork of projects shows a process of agriculture intensification in North China during the Neolithic, the impact of cereal farming on animal husbandry and their mutual interaction remain cloudy. This study reports bone collagen δ13C and δ15N of humans and animals from Wayaogou (ca 6.5–6.0 kyrs bp ) and Dongying (ca 5.9–5.6 kyrs bp , 4.6–4.0 kyrs bp ) to explore temporal trend of livestock raising and particularly the importance of millet fodder to stock raising practices in the Wei River valley, North China. The isotopic evidence overall shows that millet products increased in human and domestic animal diets during the mentioned chronological span. δ13C values of pigs and dogs at Dongying are higher than those at Wayaogou, implying that the importance of millet nutrients increased to animal husbandry diachronically. Interestingly, δ13C results of domestic cattle of Dongying late phase (−14.1 ± 1.1‰, N = 5) are more enriched than Wayaogou wild Bos (−17.8 ± 0.3‰, N = 3), indicating that millet fodder had taken a significant place in early cattle husbandry. Besides, differences between Bos species of the two periods also imply that δ13C values of bone collagen constitute a potential indicator for tracing the origin of cattle husbandry in North China. In addition, domestic sheep at Dongying produced similar isotope data to wild ovicaprid at Wayaogou, suggesting that they possibly had grazed for the most in grassland and therefore experienced a different lifestyle from cattle. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
943.
Peter W. Abrahams Jane A. Entwistle Robert A. Dodgshon 《Journal of Archaeological Method and Theory》2010,17(3):231-248
X-ray fluorescence spectrometry (XRFS) was used in the analysis of A horizon soil samples collected from a former farming
settlement and its associated area of infield (i.e. arable) located in the Central Highlands of Scotland. To date, XRFS has not been extensively used in geoarchaeological research,
but in our study the simultaneous multi-element capabilities of this instrumental technique allowed the total concentrations
of 25 major, minor, and trace elements to be fully quantified with acceptable levels of accuracy and precision. Included within
this group of chemical elements are a number (e.g. Ba, Ca, P, Pb, Sr and Zn) that have proved to be of value to archaeological interpretation in earlier investigations undertaken
in Scotland. In our preliminary work documented here, significant differences were found between the A horizon soils of former
settlement and infield areas for 18 chemical elements. Subjecting the XRFS data—and three other measured variables: soil organic
carbon (SOC), pH and A horizon depth—to discriminant analysis indicates that soils of former settlement and arable farming
can be effectively classified according to their pH, SOC content and Ca, Cu, Mg, Rb, and Zn concentrations. The inference
is that areas of former infield and settlement elsewhere at this study location in the Central Highlands may be able to be
identified according to their soil chemical composition and use of discriminant function, even though the surface remains
of pre-eighteenth century settlement sites are not readily evident today because they were constructed of perishable materials. 相似文献
944.
945.
946.
The rate of reaction of a natural hornblende garnet granulite with water under a range of mid- to lower crustal conditions has been investigated experimentally. In runs of between 7 and 84 days small but measurable amounts of water were consumed, and sheet silicates (300°C, 300 MPa and 400°C, 400 MPa) and/or secondary actinolite (400°C, 400 MPa and 500°C, 500 MPa) were observed to have grown. When normalized to the surface area of the starting materials, hydration rates were in the range of 2–5 × 10−8 g m−2 sec−1 . These reaction rates imply that a film of water that infiltrated a planar crack with a half width of 100 μm would be completely consumed within c. 100 years. These results imply that where water infiltrates the crust along faults or underlying shear zones in response to a deformation, it will remain as a free phase for only a finite period of time, which in some cases will be less than the repeat time for major earthquakes in the fault system. Thus, the rheology of fault zones and shear zones is likely to be cyclical, with the zone becoming stronger with time as water is consumed, and then weakened by infiltration of water after each rupture. 相似文献
947.
The adsorption onto other minerals of charged gold nanoparticles, carried by gas ascending from the Earth’s interior, is an important component of their transport and deposition in surficial cover such as alluvial, aeolian, and glacial sediments. To simulate the adsorption of these particles, an experiment was conducted in which a flow of air that contained gold nanoparticles was passed upward through a sample of alluvium from the middle–lower reaches of the Yangtze River. These experiments showed that gold nanoparticles are adsorbed on kaolinite, halloysite, goethite, and hematite in the alluvial cover. Both the gold nanoparticles and minerals (i.e., kaolinite, halloysite, goethite, and hematite) carry surface charges that provide them with excellent adsorption properties. This study showed that the specific mineral composition of surficial alluvial cover affects the concentration of gold nanoparticles in the ascending gas. This phenomenon may plausibly be used in exploration for concealed gold, copper–gold, and silver–gold deposits in areas of thick alluvial cover. Geofluids (2010) 10 , 438–446 相似文献
948.
949.
This paper presents evidence for increased recovery of organic residues from archaeological pottery through use of a microwave‐assisted liquid chromatography protocol. C16:0 and C18:0 saturated fatty acids were obtained from archaeological potsherds recovered from nine Neolithic settlements in the Middle East dating between 4700 and 7300 cal bc , including materials that had not produced evidence for the survival of any lipid species through use of ‘conventional’ solvent extraction techniques. Compound‐specific isotopic analyses of C16:0 and C18:0 fatty acids in potsherd extracts subsequently revealed δ13C/δ12C compositions consistent with modern subcutaneous fats of wild boar and goats pastured on lands adjacent to the Jordan Valley, and residues from a modern pottery vessel used in the manufacturing of butter, cheese and yogurt in central Turkey. These results are presented as an illustration of capabilities of the microwave‐assisted recovery protocol. The reclamation of saturated and unsaturated fatty acids from archaeological pottery fragments recovered from a number of the earliest ceramic horizons in the Middle East is herewith reported, and the extraction methods and instrumental analytical techniques are described. 相似文献
950.
P. W. J. GLOVER 《Archaeometry》2010,52(2):320-342
Twin‐probe and 33‐fold multiplexed Wenner electrical resistivity surveys were carried out at New Bewick, northern UK to examine the extent of crop marks and potential Grubenhäuser (sunken‐featured buildings, sunken‐floored buildings or SFBs). The twin‐probe method was faster, but provided data with a lower spatial resolution. However, the Wenner array data was affected by characteristic ‘M’‐ or ‘W’‐shaped responses over filled excavations such as those expected to represent a Grubenhaus. The raw Wenner array data have been analysed using one‐dimensional and two‐dimensional predictive deconvolution in order to remove these artefacts. The deconvolution was carried out using an inverse matrix element method. The filtered results indicate the presence of anomalies consistent with the presence of at least six Grubenhäuser and other anomalies concurrent with the linear crop‐marks. One particular anomaly measured about 5 m by 4 m and with a pit depth of 0.6 m below 0.3 m of topsoil. This anomaly was subsequently excavated and a Grubenhaus was discovered at the site. The excavated Grubenhaus measured 4.7 m by 3.9 m with a pit depth of 0.5 m below the base of the topsoil, confirming the electrical survey results. 相似文献