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421.
Ahmed El Emam Tareq Abdallatif Mancheol Suh Hatem Odah 《Arabian Journal of Geosciences》2014,7(2):489-503
A near-surface magnetic gradiometer survey of a site at Hawara, Fayoum city is used to delineate archaeological features made by mud bricks at shallow depths in the northeast of the pyramid of Amenemhat III. Magnetic survey data were processed to a precise forward processing sequence, including clipping, de-sloping, removing stripes and edge discontinuities, de-spiking, filtering, interpolating, and finally detecting statistically significant results. The processed magnetic data indicate high amplitude anomalies in the northeastern part of the pyramid Amenemhat III, suggesting the presence of shallow cemeteries of mud brick walls. Low pass filtering of the vertical gradient data helped reveal the relatively deep mud brick features in the generally shallow section. These features were isolated using a statistical detection technique, and verified by the correlation with the surrounding mud brick discoveries. This required the analysis of the magnetic behavior of exposed mud bricks and man-made objects for comparison with the magnetic signature of buried material. These were then matched with the vertical magnetic gradients of the exposed mud brick features from here and three other Egyptian localities. They are mostly the extension of the 12th Dynasty cemeteries, which exist in the western and southwestern parts of the study area. 相似文献
422.
Christoph Breitkreuz Hassan Eliwa Ibrahim Khalaf Khaled El Gameel Benjamin Bühler Sergei Sergeev Alexander Larionov Mamoru Murata 《Precambrian Research》2010
Chronology of Neoproterozoic volcanosedimentary successions remains controversial for many regions of the Arabian–Nubian Shield, including the Dokhan Volcanics of NE Egypt. New U–Pb zircon SHRIMP ages have been obtained for 10 silica-rich ignimbrites and two subvolcanic dacitic bodies, mapped as Dokhan Volcanics, from the North Eastern Desert of Egypt. Crystallization ages range between 592 ± 5 and 630 ± 6 Ma (Early Ediacaran). Apparently, the late consolidation of the Arabian–Nubian Shield was accompanied by the evolution of isolated volcanic centres and basin systems which developed during a period of approx. 40 Ma, independently in space and time and probably under changing tectonic regimes. The obtained age data together with other previously published reliable ages for Dokhan Volcanics suggest two main pulses of volcanic activity: 630–623 Ma and 618–592 Ma. Five samples contain inherited zircons, with ages of 669, 715–746, 847 and 1530 Ma, supporting models that North Eastern Desert crust is mainly juvenile Neoproterozoic crust. 相似文献
423.
Elżbieta Bilska-Wodecka 《GeoJournal》2006,67(4):341-355
According to Madeley’s (2003) comparative framework of state–church relations in Europe, Poland is part of the historic Northeast-Southeast multi-confessional
culture belt. The aim of this paper is to analyse the historic relationships between the Polish state and church in relation
to this framework with special attention to the post-Second World War period and to the consequences for the Polish religious
landscape. In contrast to the multi-confessionality of the historic Polish polities, after the Second World War Poland became
a mono-confessional, Roman-Catholic country. Territorial changes, the resettlement of people and the annihilation of the Jewish
population by the Nazis were responsible for this religious homogenisation. Consequently, the relationship between state and
church was almost completely confined to the relationship with the Roman-Catholic Church. During the 45 years of communist
dominance, that church became the largest public organisation independent of the state authorities and played the most important
role in the struggle against the ‘atheisation’ of Polish society as a consequence of the strong support for the church by
the majority of people. The post–1989 period is characterised by a liberalisation towards non-Catholic religious communities
and – after an initial reluctance – a positive attitude of the Polish Roman-Catholic Church (strongly supported by the Polish
Pope John Paul II) towards the Polish membership of the European Union.
相似文献
Elżbieta Bilska-WodeckaEmail: |
424.
425.
Until now, no satisfactory geodynamic model has been delivered concerning the three main West African orogens: Panafrican 1 (Bassaride belt), Panafrican 2 (Rokelide belt) and Hercynian (Mauritanide belt). However, since the last synthetic paper (Villeneuve, 2008), new geological, geophysical and geochronological data, from the Moroccan Sahara to Sierra Leone, allow us to propose a new geodynamical model. It includes the two Panafrican events in a single model very similar to the present western Pacific margin. An old “West African Neoproterozoic ocean” (WANO) was limited by a set of island arcs separated from the West African craton by a series of “back arc basins”. The closure of this first round of back arc basins around 650 Ma led to the Bassaride belt (Panafrican 1). Then the WANO was subducting underneath the island arcs (between 650 and 550 Ma) meanwhile a new generation of “back arc basins” opened to the east between the arcs and the craton margin. The closure of the WANO and associated island arcs and back arc basins (550 to 500 Ma) led to the Rokelide belt (Panafrican 2). The Hercynian structures involving a Palaeozoic cover (made with continental material) associated to a “greeenschist facies” metamorphism is ascribed to an intracontinental belt. 相似文献
426.
H. A. El Atta Ph.D. I. Aref Ph.D. 《International Journal of Environmental Science and Technology》2010,7(1):59-66
The present study was conducted in two forests in Abha (Capital of Asir Region) and two forests in Al Namas (130 km north of Abha), south western Saudi Arabia (Asir region) to investigate the effect of terraces on rainwater harvesting and growth of Juniperus procera Hochst. ex Endlicher. Farmers grow their crops within Juniper forests and woodlots by constructing terraces from soil and stones to harvest rainwater. Juniper forests and woodlots present important watersheds and sources for water. Study plots were established in four forests, two of which contained maintained terraces and the other two have been covered by abandoned and damaged terraces. The results showed that maintained terraces served as important means for rainwater harvesting, whereas abandoning of terraces resulted in increased soil loss, surface runoff, bulk density and reduced infiltration rates. Significant correlations and regression between soil loss, total runoff, soil bulk density and infiltration rate were provided. Diameter at breast height, total height, basal area, volume, number of trees, crown coverage and regeneration/ha of J. procera were significantly (P < 0.0001) higher in forests with maintained terraces compared with abandoned terraces. Finally, maintained terraces improved rainwater harvesting and growth performance of J. procera. 相似文献
427.
Samuel Wildemeersch Philippe Orban Ingrid Ruthy Olivier Grière Philippe Olive Abdelkhalek El Youbi Alain Dassargues 《Environmental Earth Sciences》2010,60(8):1753-1769
Located in the Mid-Atlas (Morocco), the Oulmes plateau is famous for its mineral water springs “Sidi Ali” and “Lalla Haya”
commercialised by the company “Les Eaux minérales d’Oulmès S.A”. Additionally, groundwater of the Oulmes plateau is intensively
exploited for irrigation. The objective of this study, essentially performed from data collected during isotopic (summer 2004)
and piezometric and hydrogeochemical field campaigns (spring 2007), is to improve the understanding of the Oulmes hydrogeological
system. Analyses and interpretation of these data lead to the statement that this system is constituted by a main deep aquifer
of large extension and by minor aquifers in a perched position. However, these aquifers interact enough to be in total equilibrium
during the cold and wet period. As highlighted by isotopes, the origin of groundwater is mainly infiltration water except
a small part of old groundwater with dissolved gas rising up from the granite through the schists. 相似文献
428.
Alexandria-Nile Delta coast,Egypt: update and future projection of relative sea-level rise 总被引:1,自引:1,他引:0
Omran El Sayed Frihy Essam A. Deabes Samy M. Shereet Farid A. Abdalla 《Environmental Earth Sciences》2010,61(2):253-273
Previous studies have indicated that the Nile River deltaic plain is vulnerable to a number of aspects, including beach erosion,
inundation, and relatively high rates of land subsidence. This issue motivates an update and analysis of new tide-gauge records,
from which relative sea-level changes can be obtained. Estimated rates from five tide gauges are variable in terms of magnitude
and temporal trend of rising sea level. Analysis of historical records obtained from tide gauges at Alexandria, Rosetta, Burullus,
Damietta, and Port Said show a continuous rise in mean sea level fluctuating between 1.8 and 4.9 mm/year; the smaller rate
occurs at the Alexandria harbor, while the higher one at the Rosetta promontory. These uneven spatial and temporal trends
of the estimated relative sea-level rise (RSLR) are interpreted with reference to local geological factors. In particular,
Holocene sediment thickness, subsidence rate and tectonism are correlated with the estimated rates of relative sea-level change.
From the relatively weak correlation between them, we presume that tectonic setting and earthquakes, both recent and historical
ones, contribute more to accelerated RSLR than that of dewatering and compression/dewatering of Holocene mud underlying the
Nile Delta plain. As a result, large areas of the coastal plain have been subsided, but some sectors have been uplifted in
response to tectonic activities of thick underlying older strata. Projection of averaged sea-level rise trend reveals that
not all the coastal plain of the Nile Delta and Alexandria is vulnerable to accelerated sea-level rise at the same level due
to wide variability of the land topography, that includes low-lying areas, high-elevated coastal ridges and sand dunes, accretionary
beaches, and artificially protective structures. Interaction of all aspects (tectonic regime, topography, geomorphology, erosion
rate, and RSLR rate) permitted to define risk areas much vulnerable to impacts of sea incursion due to accelerated sea-level
rise. 相似文献
429.
Groundwater resources use and management in the Amu Darya River Basin (Central Asia) 总被引:2,自引:0,他引:2
Shavkat Rakhmatullaev Frédéric Huneau Jusipbek Kazbekov Philippe Le Coustumer Jamoljon Jumanov Bouchra El Oifi Mikael Motelica-Heino Zbynek Hrkal 《Environmental Earth Sciences》2010,59(6):1183-1193
This paper analyses groundwater resources use and management in the socio-economic context of the Amu Darya River Basin which
covers a part of the following landlocked Central Asian countries: Afghanistan, Tajikistan, Turkmenistan and Uzbekistan. These
agrarian nations for sustaining their vital agricultural productions started to use groundwater during the recent drought
years (1998–2001) because of its relatively good quality and quantity and as an alternative to highly mineralized surface
waters. Present extent of groundwater resources use is discussed with consideration to their reserves, quality, and institutional
management and transboundary aspects within the basin. After the collapse of the centralized water resources management system
and infrastructure of the former Soviet Union, new underdeveloped systems are being practiced over the whole Amu Darya River
Basin. The critical situation of groundwater management in Afghanistan is also discussed. This work attempts to document the
management and use of groundwater in the Amu Darya Basin and present time management realities, with fragmented and weak national
and regional regulation on groundwater. Special attention is given to groundwater resources in irrigated agriculture, which
increased use in all countries of the basin is due to quick access to underground resources and relatively good quality and
quantity. 相似文献
430.
Modeling in situ benzene bioremediation in the contaminated Liwa aquifer (UAE) using the slow-release oxygen source technique 总被引:5,自引:4,他引:1
Mohamed Mostafa Ahmed Mohamed Nawal E. Saleh Mohsen M. Sherif 《Environmental Earth Sciences》2010,61(7):1385-1399
Dissolved benzene was detected in the shallow unconfined Liwa aquifer, UAE, which represents the main freshwater source for
the nearby residence Bu Hasa camp area. The main source of this contamination is believed to be the rejected water released
from Bu Hasa liquid recovery plant. In this paper, a finite element model (METABIOTRANS) is used to simulate the fate and
transport of the dissolved benzene plume in Liwa aquifer. Different remediation scenarios were simulated in which the slow-release
oxygen source (SOS) technique is utilized to minimize benzene concentrations at the nearest camp supply wells downstream of
the contamination zone. Results of the remediation scenarios show that the highest biodegradation rates occur when the oxygen
source is placed near the plume center; where higher benzene concentrations exist. The nearest oxygen release source to the
contamination zone caused higher stimulation to bacterial growth than further down-gradient oxygen sources. It also exhibited
longer resident time of oxygen in the aquifer; and therefore, yielded higher reductions in benzene concentrations. However,
using one central SOS proved to be insufficient as contaminant escaped laterally. Additional four transverse oxygen sources
were necessary to capture benzene that laterally spread away from the contamination zone. These lateral SOSs were essential
to reduce benzene concentrations at the supply wells that are located at the plume fringes. Finally, it was found that increasing
oxygen release from one source did not always improve remediation; and that using several SOSs with lower release rates could
be a more practical approach to enhance benzene biodegradation in the aquifer. 相似文献