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151.
Geoff Kuehne 《社会与自然资源》2014,27(5):492-506
This exploratory study aims to examine (1) the reasons for farmers’ range of climate change beliefs and (2) how those beliefs affect their climate change adaptation responses. Interviews with 11 key-informant irrigators from the South Australian Riverland uncovered skepticism about climate change predictions. Interviewees mostly believed changes to the climate were not human-induced but were a result of natural cycles, which meant that they then felt less obliged to undertake climate-change adaptation responses. With low water allocations and low commodity prices, most did not identify climate change as their most compelling problem. They found it hard to identify climate change adaptation options beyond those they had implemented to manage their immediate problems. The reasons for interviewees’ stated skepticism are complex, but not as equated to disbelief as they might seem. Their beliefs about climate change appear to be chosen to allow them to retain hope for the future. 相似文献
152.
An extensive sediment transport survey took place at Lihir Island (Papua New Guinea), where mining operations involve disposal of waste rocks and soil in nearshore waters. To investigate the potential impact of these practices over neighbouring fringing reefs, turbidity and sediment accumulation were measured continuously for extended periods. Turbidity records provided a map of observed impact zones based on turbidity thresholds. The main zoning features were (a) that an extreme turbidity gradient persists between the inner harbour (turbidity levels of 100-1000 mg l(-1)) and the adjacent reefs (turbidity levels in the order of 10 mg l(-1)), and (b) that observed zones conform with pre-operations impact predictions. Accumulation measurements unveiled no significant sediment accumulation over fringing coral reefs. This study contributes to the understanding of the potential impact of sediment discharge to nearshore waters. 相似文献
153.
The 1991–1993 lava flow is the most voluminous flow erupted at Mount Etna, Sicily, in over 300 years. Estimates of the volume
obtained by various methods range from 205×106 m3 (Tanguy 1996) to over 500×106 m3 (Barberi et al. 1993). This paper describes the results of an electronic distance measurement (EDM)-based field survey of
the upper surface of the 1991–1993 flow field undertaken in 1995. The results were digitised, interpolated and converted into
a digital elevation model and then compared with a pre-eruption digital elevation model, constructed from a 1 : 25 000 contour
map of the area, based on 1989 aerial photographs. Our measurements are the most accurate to date and show that the 1991–1993
lava flow occupies a volume of 231±29×106 m3.
Received: 20 July 1996 / Accepted: 5 November 1996 相似文献
154.
P. A. W. Robertson J. MacInnes O. A. E. Sparagano I. Purdom Y. Li D. H. Yu Z. J. Du H. S. Xu B. Austin 《中国海洋大学学报(英文版)》2002,1(2):153-156
Pollution has a considerable effect on biological communities, in terms of size and diversity of the populations. Yet, the
precise consequences of human activity on microbial communities in the marine environment are poorly understood. Therefore,
in an ongoing collaborative research programme between Heriot-Watt University and the Ocean University of Qingdao, bacteria
were isolated in 1999 and 2000 from marine sediment, seawater, seaweed, fish and shellfish, taken from locations in Shandong
Province adjacent to Qingdao. Sampling locations were comprised of industrial and aquacultural sites and a clean, control
site. In order to analyse microbial diversity, a polyphasic approach was adopted for characterisation of these isolates, specifically
through examination of key phenotypic traits, i.e. using Biolog GN MicroPlate™ profiles, bacterial whole cell protein profiles and 16S and 23S rRNA gene sequences. These techniques yielded complex taxonomic
data, which were subjected to statistical and cluster analyses. The application of these methods to studies of microbial communities
is discussed. 相似文献
155.
Aerobic, heterotrophic bacteria, recovered from two sites located on the west coast of Scotland, were compared to cultures
obtained in a similar way from industrial, aquacultural and clean sites in the vicinity of Qingdao, Shandong, P. R. China.
Gram-negative bacterial cultures were examined by BIOLOG-GN, and the data analysed by the simple matching (SSM) and Jaccard coefficients (SJ) and unweighted average linkage clustering using NTSys. The output revealed that 20% of the bacteria, namely, Acinetobacter johnsonii, Aquaspirillum dispar, Pseudomonas spp. (two groups), Sphingobacterium sp., Vibrio, sp., V. campbellii, V. mimicus and V. hollisae, were common between the two geographical locations. However, the study revealed shortcomings with the BIOLOG-GN system for
the study of coastal Gram-negative bacteria. 相似文献
156.
H.-P. Plag W.E.N. Austin D.F. Belknap R.J.N. Devoy J. England H. Josenhans J.D. Peacock K.S. Petersen K. Rokoengen J.D. Scourse D.E. Smith R.T.R. Wingfield 《地学学报》1996,8(3):213-222
Sea levels of the past 20 kyr are largely determined by the response of the Earth to the last ice age. Consequently, sea-level indicators are an important source of information about the interaction between cryosphere and hydrosphere and the solid Earth. Based on the material presented at a recent European Science Foundation conference, the present paper pin-points some of the topics currently under discussion with respect to sea-level evidence found on continental shelves. These topics include possible effects of erosion and changes in palaeotidal ranges on indicators of former relative sea levels as well as the problems involved in the determination of palaeo-water depth in addition to former sea levels. More evidence is being gathered for substantial small-scale patterns in the sea-level changes at or nearby to the former ice margins. These patterns are not reproduced by the available geophysical models, which reconcile on first-order level only the large-scale pattern. 相似文献
157.
L. Golub E. DeLuca G. Austin J. Bookbinder D. Caldwell P. Cheimets J. Cirtain M. Cosmo P. Reid A. Sette M. Weber T. Sakao R. Kano K. Shibasaki H. Hara S. Tsuneta K. Kumagai T. Tamura M. Shimojo J. McCracken J. Carpenter H. Haight R. Siler E. Wright J. Tucker H. Rutledge M. Barbera G. Peres S. Varisco 《Solar physics》2007,243(1):63-86
The X-ray Telescope (XRT) of the Hinode mission provides an unprecedented combination of spatial and temporal resolution in solar coronal studies. The high sensitivity
and broad dynamic range of XRT, coupled with the spacecraft’s onboard memory capacity and the planned downlink capability
will permit a broad range of coronal studies over an extended period of time, for targets ranging from quiet Sun to X-flares.
This paper discusses in detail the design, calibration, and measured performance of the XRT instrument up to the focal plane.
The CCD camera and data handling are discussed separately in a companion paper. 相似文献
158.
Nicolas Waldmann Daniel Ariztegui Flavio S. Anselmetti James A. Austin Jr Christopher M. Moy Charles Stern Cristina Recasens Robert B. Dunbar 《第四纪科学杂志》2010,25(7):1063-1075
Recent advances in the chronology and the palaeoclimatic understanding of Antarctic ice core records point towards a larger heterogeneity of latitudinal climate fluctuations than previously thought. Thus, realistic palaeoclimate reconstructions rely in the development of a tight array of well‐constrained records with a dense latitudinal coverage. Climatic records from southernmost South America are critical cornerstones to link these Antarctic palaeoclimatic archives with their South American counterparts. At 54° S on the Island of Tierra del Fuego, Lago Fagnano is located in one of the most substantially and extensively glaciated regions of southernmost South America during the Late Pleistocene. This elongated lake is the largest (~110 km long) and non‐ice covered lake at high southern latitudes. A multi‐proxy study of selected cores allows the characterisation of a Holocene sedimentary record. Detailed petrophysical, sedimentological and geochemical studies of a complete lacustrine laminated sequence reveal variations in major and trace elements, as well as organic content, suggesting high variability in environmental conditions. Comparison of these results with other regional records allows the identification of major known late Holocene climatic intervals and the proposal for a time for the onset of the Southern Westerlies in Tierra del Fuego. These results improve our understanding of the forcing mechanisms behind climate change in southernmost Patagonia. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
159.
Although major crustal lineaments may play an important role in mineralisation, the relationship between lineaments and mineral deposits can be quite cryptic, and structural controls may vary as a function of scale along lineaments. Major lineaments alone may be of limited use for detailed target generation. The Cloncurry Lineament in the Eastern part of the Mount Isa Inlier is a crustal scale structure defined by potential field-derived ‘worms’. Weights-of-evidence quantifies the association between mineral occurrences and this lineament. Autocorrelation is used to recognise structural controls on mineralisation at different scales, by progressively limiting the lengths of the vectors between mineral occurrence points in the autocorrelation plot. The weights-of-evidence analysis shows that Au, Au–Cu, Cu–Au and Cu deposits have a positive spatial correlation to the Cloncurry Lineament, which suggests it that acted as a primary crustal scale control on the localisation of Cu and Au through focussing mineralisation systems on a broad scale. However, autocorrelation defines a variety of local structural controls, which can be interpreted as shear zones, variably oriented fault sets, en echelon fault arrays, and potentially the orientation of bedding and/or iron formations which localise fluid flow and mineral deposition at finer scales. The results suggest that major lineaments defined by geophysical contrasts can be used in conjunction with techniques of spatial analysis for targeting structurally controlled mineralisation in areas under thin cover adjacent to mineralised terrains such as the Mt Isa Inlier. 相似文献
160.
In order to master the tendency mining-fracture-evolution characteristics of overlying strata and coal seams above working face with large inclination angle and mining depth in mining process, the 1221 working face in Zhao mine is selected as the engineering background and a mathematical model is established. The displacement variation, stress and strain of overlying strata and coal seams are simulated by using ANSYS software. In the mining process, the movement characteristics, displacement variation laws and fracture evolution characteristics of overlying strata and coal seams above working face with large inclination angle and mining depth along inclination direction are discussed. Simulation results show that with the advance of working face, the fracture development of overlying strata and coal seams is larger and larger; the area of gob is gradually expanding and the transverse stress of overlying strata and coal seams is also expanding. Stress contour of overlying strata and coal seams at both ends of gob becomes denser and denser; the activity of the overlying strata and coal seams near the up-roadway side of the gob is violent. The pressure relief zone is formed in the upper part of the strata and the roof above the gob. Large inclination angle of coal seam results in larger supporting pressure in the underside of the gob and smaller supporting pressure in the upper side of the gob. Along the inclination direction of the working face, the pressure relief zone is mainly concentrated in the outlet roadway of the working face; the fracture development and strata separation are obvious, which offer good passage for gas flow and migration. 相似文献