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961.
Robert Csaba Begy Alida Timar-Gabor Janos Somlai Constantin Cosma 《Geochronometria》2011,38(2):93-100
The biggest problem with most lakes that have no contact with other water sources and are being charged by precipitation is
the massive eutrophication. The aim of this work was to determine the sedimentation rate in order to evaluate the progress
of eutrophication for St. Ana Lake (Ciomad Mountain near the Băile Tuşnad in Harghita County (Romania)). The concentration
of 210Pb was determined by means of high resolution gamma spectrometry as well as derived from 210Po activity which was measured through alpha spectrometry; values obtained are in good agreement. For the excess 210Pb activity values between 4.0±0.5 Bq/kg and 218±20 Bq/kg have been found. As an alternative method, the 137Cs dating method was applied as well. Calculated mass sedimentation rates are in the range of 0.06±0.01 to 0.32±0.05 g/cm2 year with a mean of value of 0.15±0.02 g/cm2 year. Linear sedimentation rates yielded much higher sedimentation values (between 0.5±0.1 and 7.9±0.7 cm/year with a mean
of 2.4±0.6 cm/year), due to the predominant organic matter composition and the long suspension time of the sediment. This
is an indication for the process of eutrophication which will probably lead to the transformation of the lake into a peat
bog. 相似文献
962.
Dalia Hermon Ron Gafny Ashira Zamir Lia Hadas Marina Faerman Gila Kahila Bar-Gal 《Archaeological and Anthropological Sciences》2011,3(2):223-228
The making of ritual shrunken heads, or tsantsas, was a common practice among the Jivaro-Shuar tribes of Ecuador and Peru during the post-Columbian period. The raising interest
in the tsantsas in the late nineteenth through the twentieth century caused an increase in manufacturing of forged shrunken heads for profit.
In the current study, we examined the authenticity and possible cultural provenance of the shrunken head displayed at the
“Eretz Israel Museum, Tel Aviv” using macro- and microscopic criteria together with DNA analyses. DNA analyses have revealed
that the shrunken head represents a human male individual with a genetic profile compatible with an African ancestry and resembling
that of modern South American populations. 相似文献
963.
Kevin G. Stanley Elizabeth Cornelia Robertson Rene d’Entremont Ted Hubbard Marek Kujath 《Archaeological and Anthropological Sciences》2011,3(4):309-323
A particularly useful indicator of past vegetation are phytoliths, glassy products of plant metabolism which have distinctive
size and morphology based on the plant taxa which produced them; however, their analysis is a time-consuming task. Building
on investigations into mobilizing and sorting of synthetic polystyrene microspheres using a closed loop rectangular microelectromechanical
systems (MEMS) electrokinetic array, we investigate these devices’ utility for sorting natural microparticles. Using phytolith
samples extracted from archaeological sediment, we show that closed loop MEMS can separate the glassy bodies from both mineral
contaminants and each other. Also, small differences in polarization between the phytoliths cause lateral segregation between
particles of different sizes and shapes. This process facilitates manual analysis by providing a motive force to the phytoliths
that translates and rotates them, showing different configurations as they are propelled by the MEMS array. The organization
of the phytoliths into streams also opens the door to automated analysis using image processing. Phytolith assaying is therefore
feasible using a MEMS electrokinetic ring and merits additional research to explore the potential of this innovative approach. 相似文献
964.
Luise Ørsted Brandt Lena Diana Tranekjer Ulla Mannering Maj Ringgaard Karin Margarita Frei Eske Willerslev Margarita Gleba M. Thomas P. Gilbert 《Archaeological and Anthropological Sciences》2011,3(2):209-221
The use of wool derived from sheep (Ovis aries) hair shafts is widespread in ancient and historic textiles. Given that hair can represent a valuable source of ancient DNA,
wool may represent a valuable genetic archive for studies on the domestication of the sheep. However, both the quality and
content of DNA in hair shafts are known to vary, and it is possible that common treatments of wool such as dyeing may negatively
impact the DNA. Using quantitative real-time polymerase chain reaction (PCR), we demonstrate that in general, short fragments
of both mitochondrial and single-copy nuclear DNA can be PCR-amplified from wool derived from a variety of breeds, regardless
of the body location or natural pigmentation. Furthermore, although DNA can be PCR-amplified from wool dyed with one of four
common plant dyes (tansy, woad, madder, weld), the use of mordants such as alum or iron leads to considerable DNA degradation.
Lastly, we demonstrate that mtDNA at least can be PCR-amplified, cloned and sequenced from a range of archaeological and historic
Danish, Flemmish and Greenlandic wool textile samples. In summary, our data suggest that wool offers a promising source for
future ancient mitochondrial DNA studies. 相似文献
965.
966.
The archaeological site of Barsinia represents a model of a mixed subsistence strategy in the late antiquity of Jordan. Contrary
to historians' belief that the late antiquity economy was stagnated, archaeological evidence at the site of Barsinia points
to wealth accumulation as mirrored by the local wine industry and trade. As the economic growth may enhance population dynamics,
the study tests the population mobility at the site using strontium isotope ratios from the human tooth enamel. The study
comprised 12 right upper third molars and 12 rodent teeth samples. The results confirm that all of the sampled individuals
were local to the area (raised in the area) and whose diets were probably obtained from spatially restricted localities in
the region. 相似文献
967.
968.
Gomaa Abdel-Maksoud Ezz Eldin Abed al-Sameh Al-Shazly Abdel-Rahman El-Amin 《Archaeological and Anthropological Sciences》2011,3(3):291-308
The process of mummification had been known since the Fourth Dynasty of the Old Kingdom (ca. 2600 bc) and continued to develop throughout ancient Egyptian history. Although mummification protected the body from decay, especially
by microbes, some mummification techniques left the body susceptible to insect attack. Certain types of insects have been
detected in the mummies. In scholarly publications, most authors have dealt with microorganisms, while few have concerned
themselves in depth with the effect of insects on the mummies. This study aims to discuss the significance of insects and
the changes they affected to the mummies during embalming. To achieve this goal, experiments were carried out replicating
various mummification techniques using albino Wistar rats. Analysis and investigative techniques used included visual observation,
Fourier transform infrared spectroscopy, investigation of the surface morphology by a scanning electron microscope, and color
change by a spectrophotometer. The following insects could be identified as being present during the second and third processes
of mummification: Dermestes maculatus, Necrobia rufipes, Saprinus gilvicornis, Chrysomya albiceps, Wohlfahrtia magnifica, and Attagenus fasciatus. In addition, the majority of our findings confirmed that the degradation by insects increased with the second and third
methods of mummification. Finally, the experimental study conducted using the mummification techniques of the New Kingdom
(ca. 1570–1070 bc) indicated that they were more resistant to insect attack than the other types. 相似文献
969.
Hugo R. Oliveira Huw Jones Fiona Leigh Diane L. Lister Martin K. Jones Leonor Peña-Chocarro 《Archaeological and Anthropological Sciences》2011,3(4):327-341
Einkorn (Triticum monococcum L.) was one of the first cereals to be domesticated in the Old World ca. 10,000 years ago and to spread towards Europe and
North Africa. Its cultivation declined before the Iron Age and it remains today only as a relic crop in remote areas. To investigate
if the geographic distribution of genetic diversity in modern einkorn landrace accessions could be informative about the movement
of this crop during prehistory, we genotyped 50 accessions of einkorn from Europe, North Africa and the Near East. Using nuclear
and chloroplast microsatellites and clustering methods, we detected two main gene pools in einkorn. The distribution of these
lineages revealed differences between accessions from Morocco and the Iberian Peninsula from the rest of Europe and the Near
East and suggests different regional dynamics in the spread of this crop. 相似文献
970.