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81.
82.
The Seferihisar–Balçova Geothermal system (SBG) is characterized by complex temperature and hydrochemical anomalies. Previous geophysical and hydrochemical investigations suggest that hydrothermal convection in the faulted areas of the SBG and recharge flow from the Horst may be responsible for the observed patterns. A numerical model of coupled fluid flow and heat transport processes has been built in order to study the possible fluid dynamics of deep geothermal groundwater flow in the SBG. The results support the hypothesis derived from interpreted data. The simulated scenarios provide a better understanding of the geophysical conditions under which the different fluid dynamics develop. When recharge processes are weak, the convective patterns in the faults can expand to surrounding reservoir units or below the seafloor. These fault‐induced drag forces can cause natural seawater intrusion. In the Melange of the Seferihisar Horst, the regional flow is modified by buoyant‐driven flow focused in the series of vertical faults. As a result, the main groundwater divide can shift. Sealing caprocks prevent fault‐induced cells from being overwhelmed by vigorous regional flow. In this case, over‐pressured, blind geothermal reservoirs form below the caprocks. Transient results showed that the front of rising hot waters in faults is unstable: the tip of the hydrothermal plumes can split and lead to periodical temperature oscillations. This phenomenon known as Taylor–Saffman fingering has been described in mid‐ocean ridge hydrothermal systems. Our findings suggest that this type of thermal pulsing can also develop in active, faulted geothermal systems. To some extent, the role of an impervious fault core on the flow patterns has been investigated. Although it is not possible to reproduce basin‐scale transport processes, this first attempt to model deep groundwater geothermal flow in the SBG qualitatively supported the interpreted data and described the different fluid dynamics of the basin. Geofluids (2010) 10 , 388–405  相似文献   
83.
In this work we report a pre‐restoration spectroscopic study by a multi‐technique approach on the green pigment and the binder used in illuminations in a codex of the late 15th century. Our analysis aimed to characterize the badly deteriorated parts of the codex, mainly the green parts, by electron paramagnetic resonance (EPR), X‐ray diffraction (XRD), X‐ray fluorescence (XRF) and infrared spectroscopy (ATR‐IR). We will show that a combined study by EPR and IR spectroscopies on model systems allowed us to refine the general information obtained with the other techniques and to identify the binding media surrounding the chromophore Cu(II) ion.  相似文献   
84.
In ancient Goryeo celadon excavated from the kiln sites in the GangJin and Buan areas, the effect of the chemical composition and ionic state of Fe on the colour was evaluated by Mössbauer spectroscopy and chromaticity analysis. According to chromaticity analysis, the L* value (brightness) of the glaze was shown to be affected more by TiO2 and MnO than by Fe2O3, and the body was affected more by Fe2O3 than by TiO2. The a* value was found to be affected by Fe2O3 and TiO2 in the glaze, whereas there was hardly any change in the body according to the composition. As for the b* value, changes due to the composition were shown to be smaller than those for the L* and a* values. According to the Mössbauer spectroscopy results, as the quantities of TiO2 and Fe2O3 are increased, Fe2+/Fe3+ decreases; while the changes in Fe2+/Fe3+ with MnO and P2O5 are negligible. As the quantity of Fe2+/Fe3+ increases, the a* and b* values decrease, which results in the change of colour from red–yellow to blue–green. The characteristic green colour can be attributed to increased L* (brightness) and decreased a* and b* values (blue–green shift) due to the reduced Fe ion, which is mainly determined by the TiO2 and Fe2O3 contents.  相似文献   
85.
Macroscopic examination, histomorphometry and Fourier Transform Infrared Spectroscopy (FTIR) are applied to the analysis of burned bones from the early Anglo-Saxon cemetery at Elsham in Lincolnshire, UK. These methods were undertaken to gain a greater understanding of pyre conditions from an archaeological context and the effects of burning on bone microstructure. Sixteen samples were employed for thin-section analysis while eight samples were used with FTIR. The results suggest that these methods correspond well with macroscopic examination, though anomalies did occur. The techniques employed in this paper have demonstrated that the temperatures reached on the funerary pyres at Elsham ranged from 600 °C to over 900 °C under oxidizing conditions.  相似文献   
86.
Micro‐bead manufacture is geographically widespread from the fifth millennium bc . Previous studies of comparable micro‐beads from sites in the Indus Valley region and the Near East suggest that many of these beads were formed from synthetic enstatite. Characterization of micro‐beads from the Late Chalcolithic site of Çaml?bel Tarlas? was carried out by optical microscopy (OM), scanning electron microscopy (SEM) and microanalysis with energy‐dispersive X‐ray spectroscopy (EDS), and X‐ray diffraction analysis (XRD). The chemical composition of the micro‐beads analysed indicated that they were made from three distinctive materials; namely, bulk talc (i.e., synthetic enstatite precursor), apatite and mineral‐rich clay pastes.  相似文献   
87.
J. U. Powell 《Folklore》2013,124(3):310-315
The colours red, white, and black occur together in folktales, ritual contexts, and traditional art forms around the world. This article draws together research from folklore, linguistics, art history, vision science, perceptual philosophy, and primate biology to propose an evolutionary source underlying the symbolic resonance of these colours.  相似文献   
88.
89.
In the present series we have dated two samples from a previously unknown pilework E. of the Kastelholm castle, two other logs from old layers to the S. of the castle, two charcoal samples from a layer E. of the castle, four samples of various materials from a ditch SE of the castle, and one sample from outside the NE part of the castle. All the samples were carefully pre‐treated, δ13C normalization performed and the measurements extended to reach a statistical uncertainty of usually less than ±60 years. The results are given in radiocarbon years and calibrated.  相似文献   
90.
The crystallinity of bone mineral represents an established method of measuring heat-induced change and is of importance to fields including material science, clinical science, anthropology and archaeology. A commonly used technique involves the calculation of the Crystallinity Index (CI) using selected peaks from Fourier Transform Infrared (FTIR) absorbance spectra. However, the choice of peaks has to date not been statistically justified. In this study a novel application of statistical techniques to the FTIR spectra of bone samples burned in the range 100 °C–1100 °C has been used to identify 5 new spectral indices of heat-induced crystallinity change. The validity of the new indices was tested by using a statistical classification model (LDA) to predict the burning temperature of a set of 108 bone samples burned between 100 °C and 1100 °C. A correct classification rate (CCR) of 97.2% was obtained when a combination of 4 indices including the CI was used. This was significantly better than the CCR of 66.7% which was obtained when the CI was used on its own.  相似文献   
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