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1.
The Holocene history of the Danube Delta has been studied using 14C analyses of faunal material. The principal phases of development include: (1) initial Letea Caroarman spit, 11,700–9800 yr B.P. in its central part, 8800-5500 yr B.P. in its southern part; (2) Sf. Gheorghe I Delta, 8900-7200 yr B.P.; (3) Sulina Delta, 7200-2000 yr B.P., and (4) Sf. Gheorghe II Delta-Chilia Delta 2000 yr B.P.-present. Other smaller-scale features have also been dated, including secondary deltas (Co?na and Sinoe Deltas) and littoral bars. Age determinations carried out on whole samples were erratic and it was found that individual species had to be separated and dated. In all cases, the older dates were of transported material whereas the younger dates gave the true age of the formation. 相似文献
2.
Industrial archaeology has developed as an important aspect of conservation during the second half of the twentieth century
in the Western world and there have been great opportunities in transition countries since 1989 on account of economic restructuring
and the importance given to 'niche' tourism. While the core interest lies with machines and industrial buildings, attention
is also given to transport systems and the social context, with respect to relations between owners, managers and workers.
Moreover, the desirability of maintaining old industrial installations within their traditional landscape settings enables
industrial archaeology to make a contribution to sustainable development. This paper considers the prospects for Romania,
with particular reference to the Reşiţa area of the Banat Carpathians. The mineral resources of this region gave rise to a
metallurgical industry which was established under Habsburg administration in the eighteenth century and continues today.
In addition to the principal factories in Anina and Reşiţa, the mining installations, transport systems and power stations
contribute to a diverse industrial region in a distinctive physical and cultural setting. The development of the complex is
summarised and the opportunities for conservation are evaluated. The tourist infrastructure of the area is also examined with
regard to the range of accommodation available.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
Ionel Nicolae Ioan Seghedi Iuliu Boboş Maria do Rosário Azevedo Sara Ribeiro Mihai Tatu 《Chemie der Erde / Geochemistry》2014
An Early Permian volcanic assemblage is well exposed in the central-western part of the Apuseni Mountains (Romania). The rocks are represented by rhyolites, basalts and subordinate andesites suggesting a bimodal volcanic activity that is intimately associated with a post-orogenic (Variscan) syn-sedimentary intra-basinal continental molasse sequences. The mafic and mafic-intermediate rocks belong to sub-alkaline tholeiitic series were separated in three groups (I–III) showing a high Th and Pb abundances, depletion in Nb, Ta and Sr, and slightly enriched in LREE patterns (LaN/YbN = 1.4–4.4). Isotopically, the rocks of Group I have the initial ratios 87Sr/86Sr(i) = 0.709351–0.707112, 143Nd/144Nd(i) = 0.512490–0.512588 and high positive ?Nd270 values from 3.9 to 5.80; the rocks of Group II present for the initial ratios values 87Sr/86Sr(i) = 0.709434–0.710092, 143Nd/144Nd(i) = 0.512231–0.512210 and for ?Nd270 the negative values from −1.17 to −1.56; the rocks of Group III display for the initial ratios the values 87Sr/86Sr(i) = 0.710751–0.709448, 143Nd/144Nd(i) = 0.512347–0.512411 and for ?Nd270 the positive values from 1.64 to 2.35. The rocks resembling continental tholeiites, suggest a mantle origin and were further affected by fractionation and crustal contamination. In addition, the REE geochemistry (1 > SmN/YbN < 2.5; 0.9 > LaN/SmN < 2.5) suggests that these rocks were generated by high percentage partial melting of a metasomatized mantle in the garnet peridotite facies. The felsic rocks are enriched in Cs, Rb Th and U and depleted in Nb, Ta, Sr, Eu, and Ti. The REE fractionation patterns show a strong negative Eu anomaly (Eu/Eu* = 0.23–0.40). The felsic rocks show the initial ratios the values: 87Sr/86Sr(i) = 0.704096–0.707805, 143Nd/144Nd(i) = 0.512012–0.512021 and for ?Nd270 the negative values from −5.27 to −5.44. They suggest to be generated within the lower crust during the emplacement of mantle-derived magmas that provided necessary heat to crustal partial melting. 相似文献
4.
Calcic skarns and transversal zoning in the Banat mountains, Romania: indicators of an Andean-type setting 总被引:1,自引:1,他引:0
Ş. N. Vlad 《Mineralium Deposita》1997,32(5):446-451
Calcic skarn deposits related to Upper Cretaceous – Paleocene banatitic intrusions are widely developed in the Banat Mountains
(southwestern Romanian Carpathians). There is a spatial distribution of banatitic igneous rocks and associated ore deposits
in parallel zones, due to subduction beneath the southwest Carpathians. As a result three distinct petro-metallogenetic units
developed, i.e. marginal unit: Moldova Nouă– Sasca; median unit: Ciclova – Oravita; and the inner unit: Dognecea – Ocna de
Fier. The magmatism changed inland from monzonite and diorite → granodiorite occurrences to granodiorite → granite plutons.
The related mineralization shifted simultaneously from Cu (Mo) to Cu-Mo (W) and eventually Fe(Cu)/Pb-Zn. The distribution
of both magmatism and related ore deposits in parallel petro-metallogenetic zones is considered similar to that in the Andes.
In particular, calcic skarns and related ore deposits that occur in these units show a transversal zonal variation represented
by compositional features of pyroxene and granat, sequence of mineralization and metallogenetic environment. Such zonal characteristics
represent an additional but nonetheless significant indicator for an Andean-type subduction-related setting.
Received: 3 June 1996 / Accepted: 10 January 1997 相似文献
5.
Aurelian Andrei Radu Tatiana Angelescu Valentin Curtef Florin Delia Daniel Felea Ioana Goia Dumitru Ha?egan Bogdan Lucaschi Ancuta Manea Vlad Popa Ioan Rali?? Radu V?c?reanu 《Experimental Astronomy》2012,34(1):31-42
Around the world, several scientific projects share the interest of a global network of small Cherenkov telescopes for monitoring observations of the brightest blazars??the DWARF network. A small, ground based, imaging atmospheric Cherenkov telescope of last generation is intended to be installed and operated in Romania as a component of the DWARF network. To prepare the construction of the observatory, two support projects have been initiated. Within the framework of these projects, we have assessed a number of possible sites where to settle the observatory. In this paper we submit a brief report on the general characteristics of the best four sites selected after the local infrastructure, the nearby facilities and the social impact criteria have been applied. 相似文献
6.
Livio Belegante Doina Nicolae Anca Nemuc Camelia Talianu Claude Derognat 《Acta Geophysica》2014,62(2):276-289
In this study, we used boundary layer heights derived from lidar in Romania to validate the Weather Research Forecast (WRF) model improved by ARIA Technologies SA in the framework of ROMAIR LIFE project. Lidar retrievals were also compared to the retrievals from meteorological data, both modeled (Global Data Assimilation System; GDAS) and measured (microwave radiometry). Both the gradient and the wavelet covariance methods were used to compute the boundary layer height (BLH) from the range corrected lidar signal, and their equivalence was shown. The analysis was performed on 102 datasets, spread over all seasons and 3 years (2009–2011). A good agreement was found for the remote sensors (lidar and microwave radiometer) which are co-located and measure simultaneously. The correlation of the measured boundary layer height and the modelled one was 0.66 for the entire dataset, and 0.73 when considering daytime data, i.e., for a well defined boundary layer. A systematic underestimation of the boundary layer height by the WRF during non-convective periods (nocturne, stable atmosphere) was found. 相似文献
7.
The orbital period variation of the oEA system Y Leo is revised by taking into account new times of minimum light covering
an extended time base of 101.8 yr. A multiperiodic ephemeris was finally established by carefully approaching the problem of periodicity detection for the considered periodic
components. A method relying on Monte Carlo simulations was applied. The problem of the long-term behaviour of the O–C curve was taken into account using parabolic, and parabolic + periodic ephemerides. The physical interpretation of the mathematical models describing both long- and short-term behaviour of the
O–C curve was performed by considering different mechanisms: the conservative mass transfer, the light-time effect, and the orbital
period modulation through the cyclic magnetic activity of the late spectral type secondary component in the system. The consequences
of these interpretations are rather intriguing and emphasize the need of new and detailed observational studies on Y Leo. 相似文献
8.
We investigate the regional thermal structure of the crust in Mexico using Curie Point Depth (CPD) estimates. The top and bottom of the magnetized crust were calculated using the power-density spectra of the total magnetic field from the freely available ??Magnetic Anomaly Map of North America??. We applied this method to estimate the regional crustal thermal structure in overlapping square windows of 2°?×?2°. The CPD estimates range between 10 and 40?km and show several regions of relatively shallow and deep magnetic sources, with a general inverse correlation with measured heat flow. A deep CPD region (20?C30?km) is located in the fore-arc area where the subducting Cocos plate has a flat-slab geometry. This deep region is bound to the NW and SE by shallow CPD areas beneath the states of Michoacan (CPD?=?12?C16?km) and Oaxaca (CPD?=?~16?km), respectively. There is a good spatial correlation between this deep CPD area and two main fracture zones located on the incoming Cocos plate (Orozco and O??Gorman fracture zones), suggesting that subduction plays an important role in setting apart different CPD provinces along the Mexican coast. Another deep CPD (16?C32?km) area corresponds to the region where the Rivera plate subducts beneath Jalisco block. The Trans-Mexican Volcanic Belt is characterized by a decrease in Curie depths from west (16?C20?km) to east (10?C12?km). Finally, several deep CPD areas are situated in the back-arc region where old Mesozoic terrains are present. Our results suggest that the main control on the crust??s regional thermal structure in the fore-arc and volcanic arc regions is due to the subduction of the Cocos and Rivera plates beneath Mexico. 相似文献
9.
Carlos Carbonell Carrera Bogdan Vlad Avarvarei Elena Liliana Chelariu Lucia Draghia Simona Catrinel Avarvarei 《The Journal of geography》2017,116(5):197-205
Landforms often are represented on maps using abstract cartographic techniques that the reader must interpret for successful three-dimensional terrain visualization. New technologies in 3D landscape representation, both digital and tangible, offer the opportunity to visualize terrain in new ways. The results of a university student workshop, in which traditional 2D versus 3D digital and tangible models were tested, suggest that map-reading skill development is greater when using the 3D technologies. 相似文献
10.
Irina Popescu Gilles Lericolais Nicolae Panin Marc De Batist Hervé Gillet 《Geo-Marine Letters》2007,27(2-4):173-183
This study is a synthesis of gas-related features in recent sediments across the western Black Sea basin. The investigation
is based on an extensive seismic dataset, and integrates published information from previous local studies. Our data reveal
widespread occurrences of seismic facies indicating free gas in sediments and gas escape in the water column. The presence
of gas hydrates is inferred from bottom-simulating reflections (BSRs). The distribution of the gas facies shows (1) major
gas accumulations close to the seafloor in the coastal area and along the shelfbreak, (2) ubiquitous gas migration from the
deeper subsurface on the shelf and (3) gas hydrate occurrences on the lower slope (below 750 m water depth). The coastal and
shelfbreak shallow gas areas correspond to the highstand and lowstand depocentres, respectively. Gas in these areas most likely
results from in situ degradation of biogenic methane, probably with a contribution of deep gas in the shelfbreak accumulation.
On the western shelf, vertical gas migration appears to originate from a source of Eocene age or older and, in some cases,
it is clearly related to known deep oil and gas fields. Gas release at the seafloor is abundant at water depths shallower
than 725 m, which corresponds to the minimum theoretical depth for methane hydrate stability, but occurs only exceptionally
at water depths where hydrates can form. As such, gas entering the hydrate stability field appears to form hydrates, acting
as a buffer for gas migration towards the seafloor and subsequent escape. 相似文献