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191.
Low-temperature metamorphic petrology occupies the P?CT field between sedimentary and metamorphic petrology. Two important pillars of low-temperature metamorphism are coal petrology and clay mineralogy. When low temperature petrology was established bridging a hiatus between the two classical geological disciplines of sedimentary geology and metamorphic petrology, geologists faced a need for the usage of different terminology tenets. Martin Frey and Bernard Kübler were two pioneers in low-grade metamorphic petrology. They focused their research on clarifying the relationships of clay mineralogy and organic petrology to metamorphic pressure (P) and temperature (T) conditions. The ultimate aim of M. Frey and B. Kübler was to establish a correlation between clay indices and organic parameters for different geodynamic setting and therefore for various pressure?Ctemperature (P?CT) conditions occurring in low grade metamorphic terranes. For this purpose, a special attention was addressed to the correlation between the Kübler-Index (KI) and vitrinite reflectance (VR). All these efforts are dedicated to estimate the P?CT conditions and thus to gain insight into the geodynamic evolution of low-grade metamorphic terranes. B. Kübler and M. Frey honored here concentrated their studies to the Helvetic Central Alps area. The very low-grade Helvetic domain is therefore of basic interest of this paper. Ensuing the extensive compilation of data from the Helvetic domain, a reinterpretation of Kübler and Frey??s research is presented in the light of last decade??s scientific progress. A comprehensive dataset available enables to discriminate many factors influencing the Kübler-Index and organic-matter reflectance alongside to time, temperature and pressure. The correlation is restricted to the KI and organic matter reflectance (mostly VR) because most of the studies used both methods. Organic matter reflectance (OMR) includes data from vitrinite reflectance and bituminite reflectance measurements. Geodynamics has important control on the KI/VR (OMR) correlation. Tectonic units having a similar geodynamic evolution are featured by the comparable KI/OMR trends, related to the particular paleo-geothermal conditions. Obviously the KI/OMR correlations provide a mean to characterise geothermal gradients and metamorphic very-low-grade pressure?Ctemperature conditions. In terranes where high deformations rates are reported, exceeding the high anchizone conditions, strain promotes the kinetic effects of temperature and pressure on the KI versus OMR ratio.  相似文献   
192.
A multiple inter-laboratory calibration with illite Kübler?CFrey?CKisch ??crystallinity?? index and related standards is presented and compared with CIS standards used in the last two decades in very low-grade metamorphic studies. Comparing CIS values with KI standards the CIS values show a higher full width at half-high maximum peak intensity. In all cases due to broadening effects on the Kübler-index, zone-limits, specifically the diagenetic zone/anchizone boundary, a shift is produced in geographical dimensions in a metamorphic map-view. Combining standardised Kübler-index and vitrinite?Cbituminite reflectance measurements a coherent data set for compilation studies can be generated from the data of different research groups. This attempt to establish a unified database of independent measures to determine diagenetic/metamorphic zones with different analytical instrumental methods are indispensable to present metamorphic maps at very low-grade conditions. Given that the Kübler?CFrey?CKisch standards are difficult to preserve for the future and presumably they will be replaced with ongoing time by the CIS standards, a rescue of the laboratory settings from Frey, Kübler and others is done. After having compiled the Kübler-index??vitrinite reflectance zones in the Alps for the ??New Metamorphic Map of the Alps??, the presented calibration and inter-laboratory correlation gives a chance to save the KI values obtained by very different preparation procedures applied. This is an important step for further studies in an area like the Central Alps with a very high data grid. This correlation study will also make it possible that nearly 90?% of Kübler-index data from Switzerland can be compared in future work. Using the same calibration and preparation technique no fundamental problem in data comparison is achieved for the vitrinite/bituminite reflectance data operation. The main problem arises when rock maturity is compared with CIS calibrated Kübler-index values. Kübler-index values obtained by the so-called CIS calibration are not compatible with Kübler?CFrey?CKisch (árkai, Aprahamian, Brime, Ferreiro M?hlmann, H. Krumm, Leoni, Petschick) calibrated Kübler-Indices. Applying both standardisation approaches for field studies, partially different results are obtained.  相似文献   
193.
New data and a review of historiographic information from Neolithic sites of the Malaga and Algarve coasts (southern Iberian Peninsula) and from the Maghreb (North Africa) reveal the existence of a Neolithic settlement at least from 7.5 cal ka BP. The agricultural and pastoralist food producing economy of that population rapidly replaced the coastal economies of the Mesolithic populations. The timing of this population and economic turnover coincided with major changes in the continental and marine ecosystems, including upwelling intensity, sea-level changes and increased aridity in the Sahara and along the Iberian coast. These changes likely impacted the subsistence strategies of the Mesolithic populations along the Iberian seascapes and resulted in abandonments manifested as sedimentary hiatuses in some areas during the Mesolithic–Neolithic transition. The rapid expansion and area of dispersal of the early Neolithic traits suggest the use of marine technology. Different evidences for a Maghrebian origin for the first colonists have been summarized. The recognition of an early North-African Neolithic influence in Southern Iberia and the Maghreb is vital for understanding the appearance and development of the Neolithic in Western Europe. Our review suggests links between climate change, resource allocation, and population turnover.  相似文献   
194.
Classification of Tsunami and Evacuation Areas   总被引:3,自引:2,他引:1  
On March 11, 2011, a large earthquake that occurred offshore the north-east coast of Japan generated a large tsunami which devastated extensive areas of the Tohoku coastline. Despite Japan being considered a country well prepared for these types of disasters, large casualties were recorded, with numerous discussions amongst the Japanese coastal engineering community ensuing. As a result, two different levels of tsunamis have been proposed and now recognized in Japan, depending on the frequency of such extreme events. The idea that hard measures can protect the lives of inhabitants of coastal areas has been abandoned, and these measures are only considered to be effective in protecting properties against the more frequent but lower magnitude events. Soft measures should always be used to protect against the loss of lives, and to this respect, the authors of the paper propose the introduction of a Classification of Evacuation Areas, to show which of these should be prioritized by residents as they seek to evacuate.  相似文献   
195.
Abstract

In a uniequational hedonic model, the main source of spatial dependence is found in the explained variable, since the price of a house mainly depends on the housing prices in the neighborhood (although this can also be due to other factors, such as missing covariates and the model of choice). Dependence is one of the primary causes of spatial autocorrelation in disturbances. However, such disturbances may also be spatially correlated with the disturbances of other equations; in this case, they can be considered coregionalized. This paper presents a multi-equational hedonic regression model with coregionalized disturbances and heterotopic data. The model comprises two equations. The first explains housing prices using data from a sample, while the second explains an auxiliary variable, quality of the area, obtained from a different sample. The model is then applied practically to predict housing prices. [Key words: Cokriging, housing prices, geostatistics, multi-equational hedonic model, coregionalized.]  相似文献   
196.
This study aims at monitoring the behaviour of the rainfall, runoff, drainage, soil water storage, and evapotranspiration variables involved in the water balance measured by lysimeter data. The evaluation of the water balance considered different time scales, where the components were monitored daily and in 10‐day accumulated period intervals. The results demonstrated that in wet periods the soil water content was greater at a depth of 10 cm, whereas in the dry periods a greater concentration was observed at 70 cm depth. At the depth of 30 cm, the lowest values of soil water content were observed for both wet and dry periods. The results, obtained through the use of tensiometers and time domain reflectometry installed internally and externally to the lysimeter, were very close, which was more noticeable during the periods of lower water loss by the soil. The water balance, calculated from the lysimeter data, demonstrated that 70% of the total rainfall was lost by the process of evapotranspiration. The drainage accounted for 27·5% of the precipitated water, highlighting the fact that this component should not be disregarded in the water balance calculation. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
197.
We investigated the dynamics of the continuous seismic signal recorded before and during the 2011–2012 El Hierro eruption (Canary Islands) using the innovative approach of the Fisher–Shannon method, a suitable statistical tool for detecting dynamic changes in complex systems. Our findings identify dynamic changes in the seismic signal that can be correlated with different stress states of the magmatic setting and the plumbing system in the volcano at El Hierro. The results contribute to the understanding of the fracturing pattern in the crust during a new intrusion and eruption of an overpressurized batch of magma.  相似文献   
198.
This study reports implications of different tooth marks left by carnivorous mammals on long bones of Haplomastodon waringi from the Quaternary of Águas de Araxá, Minas Gerais, Brazil. Analyses of gnawing damage by ursids, felids, and canids have shown that these groups produce pits on bone surfaces when the gnawing is superficial, and punctures more often when the prey is intensely consumed. Scratches or scoring marks are most often associated with gnawing by canids, which may spend a long time gnawing the bones, leading to differential tooth marking. The gomphothere bones at Águas de Araxá did not result from predation, but are a consequence of a local mass mortality in a period of low environmental humidity, with little water and a scarcity of food. Canids frequently act as opportunistic scavengers during periods when herbivores face food shortages. Previous studies of necrophagous dermestid larvae indicate that the gomphothere carcasses of Águas de Araxá were exposed for a long period of time after death. These insects are the last consumers of a carcass because they act only when the body fat is completely lost. Thus, the gomphothere carcasses at Águas de Araxá suffered canid necrophagy in the early stages of decomposition, possibly during a drought period. Thereafter, the gomphothere carcasses would have been exposed for a period about 230 days until the final burial event.  相似文献   
199.
Five of the most important Colombian coals were studied using Photoacoustic Fourier transform infrared (PA-FTIR) spectroscopy. The PA-FTIR spectra were used to obtain structural parameters and to determine the analytical potential of this technique. The molecular structural parameters, CH2/CH3, fa, Hal/Har, and (R/C)u were correlated with fixed carbon contained in the samples to determine aliphatic hydrogen, Hal, and the aromatic hydrogen, Har in coals studied here. These parameters enabled the determination of aromaticity, fa, which was found to be between 0.66 and 0.98. The aliphatic and aromatic regions were considered between 3005–2760 cm?1 and 912–670 cm?1, respectively. Finally, using the molecular structural parameters, the grade of maturation (rank) of coal samples studied was determined.  相似文献   
200.
Geocoding urban addresses usually requires the use of an underlying address database. Under the influence of the format defined for TIGER files decades ago, most address databases and street geocoding algorithms are organized around street centerlines, associating numbering ranges to thoroughfare segments between two street crossings. While this method has been successfully employed in the USA for a long time, its transposition to other countries may lead to increased errors. This article presents an evaluation of the centerline‐geocoding resources provided by Google Maps, as compared to the point‐geocoding method used in the city of Belo Horizonte, Brazil, which we took as a baseline. We generated a textual address for each point object found in the city's point‐based address database, and submitted it to the Google Maps geocoding API. We then compared the resulting coordinates with the ones recorded in Belo Horizonte's GIS. We demonstrate that the centerline segment interpolation method, employed by the online resources following the American practice, has problems that can considerably influence the quality of the geocoding outcome. Completeness and accuracy have been found to be irregular, especially within lower income areas. Such errors in online services can have a significant impact on geocoding efforts related to social applications, such as public health and education, since the online service can be faulty and error‐prone in the most socially demanding areas of the city. In the conclusion, we point out that a volunteered geographic information (VGI) approach can help with the enrichment and enhancement of current geocoding resources, and can possibly lead to their transformation into more reliable point‐based geocoding services.  相似文献   
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