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91.
The purpose of this paper is to assess the level of implementation of Integrated Coastal Zone Management (ICZM) principles in the Mediterranean developing countries at the moment of signing the protocol on ICZM for the Mediterranean, in the framework of the UNEP Mediterranean Action Plan of the Barcelona Convention. This assessment is based on the results of two advanced seminars on ICZM promoted by the Azahar programme of the Spanish Agency for International Cooperation for the Development (Ministry of Foreign Affairs and International Cooperation). The contribution of the participants of the seminar, who are representatives of national agencies related with ICZM in different Mediterranean countries, have been collected through a questionnaire including: (i) a ranking of the main coastal sectors and the main coastal issues of each country; (ii) significant initiatives for the sustainable development of the Mediterranean coastal zones; and (iii) the evaluation of the ICZM progress. The state of the coast, the level of implementation of ICZM and the main problems faced to apply it, have been detected for each country. None of the consulted countries have a full implemented integrated coastal zone management, the major problems being: (i) the lack of financial commitment for the implementation of ICZM; (ii) the lack of an assessment and monitoring system; (iii) the lack of knowledge regarding the coastal system; (iv) the lack of qualified human resources; and (v) the lack of public participation and administrative integration strategies based on information. From these conclusions, some recommendations to improve ICZM are also provided. The work presented in this paper is the starting point to assess the evolution and the reference from which ICZM will be improved through the protocol on ICZM for the Mediterranean.  相似文献   
92.
This paper describes new three dimensional experiments on water waves generated by landslides. The landslide is reproduced by a rigid elliptical body, sliding along an inclined plane (slope of 1/3, 1 vertical, 3 horizontal). The generated water waves are free to propagate both offshore and alongshore, since the plan dimensions of the used wave tank are of at least one order of magnitude larger than the width of the landslide, which can be considered to be a scale of the wave length. The experimental study has been carried out reproducing both subaerial and partially submerged landslides. The wave generation process is studied by means of video records of the near field flow and measurement of the landslide movement; the properties of the waves propagating along the coast are described on the basis of runup gauges. The waves observed during the experiments always present first a crest and then a trough; as the first wave propagates away from the generation area the crest tends to become smaller than the trough and the maximum runup along the coast is given by the second or by the third wave. An important feature is that the observed runup along the coast firstly grows with the distance from the generation area, it reaches a maximum value at about two times the width of the landslide, and then decreases. An estimate of the celerity at which the waves propagate along the coast is given on the basis of gauge measurements; it results that the crests propagate faster than the troughs, and the wave period increases.  相似文献   
93.
The deep seismic profile Transalp crosses, from north to south, Germany, Austria and Italy. The gravity measurements for each country were made by national agencies with different reference systems and data reduction methods. Within the frame of the Transalp-project a comprehensive database of the Eastern Alps was compiled covering an area of 3.5° by 4° in longitude and latitude (275 by 445 km), respectively. To increase the data coverage in the south Alpine area two gravity surveys were carried out, resulting in 469 areally distributed new stations, of which 215 have been measured with the intent to improve the geoid in the area of the planned Brenner Basistunnel (BBT). The resulting gravity database is the best in terms of resolution and data quality presently available for the Eastern Alps. Here the free air, Bouguer and isostatic gravity fields are critically discussed. The spatial density of existing gravity stations in the three countries is discussed. On the Italian side of the Alps the spatial density is rather sparse compared to the Austrian side. The Bouguer-gravity field varies between − 190 * 10− 5 m/s2 and + 25 * 10− 5 m/s2, with the minimum located along the Alpine high topographic chain, but with a small offset (a few tens of km) to the greatest topographic elevation, showing that the Airy-type local isostatic equilibrium does not fully apply here. The maximum of the Bouguer anomaly has an elongated shape of 100 by 50 km located between the towns of Verona and Vicenza and covers the Venetian Tertiary Volcanic Province (VTVP), a feature not directly related to the plate collision in the Eastern Alps. The gravity high is only partly explainable by high-density magmatic rocks and requires also a deeper source, like a shallowing of the Moho. The isostatic residual anomalies (Airy model) are in the range ± 50 * 10− 5 m/s2, with the greatest positive anomaly corresponding to the location of the VTVP, indicating here under-compensation of masses. At last a discussion of a 2D density model based on reflection seismic data and receiver functions is made.  相似文献   
94.
The last few years have seen the debate on the geoethics of environmental and climatic protection growing to include resilience as a central idea within this new discipline, which holds many similarities with geography. Resilience analysis often looks at the capacity to re-establish conditions of equilibrium within a system which has been hit by a serious shock, e.g. a natural or man-made disaster. Geoethics works, in tandem with geological analyses and the geography of risk, to inform a population and develop integrated risk management in such a way as to strengthen a community’s resilience. The aim of this work is to study some people’s capacity to overcome what was potentially a disastrous event and, through a process of reconstruction, turn it into an occasion for growth. The experiment, carried out in the primary and middle schools in Aiello Calabro (Calabria, southern Italy), was conducted on the basis of the belief that there is a close relationship between a population’s having a realistic understanding of the risk of such an event, e.g. an earthquake, and high levels of resilience. We also tried to gain an insight into the relationship that may exist between resilience in primary and secondary school children and methods of coping which give an appropriate management of seismic risk. To be more precise, we try to discover whether there is a link between good/appropriate resilience and good/appropriate risk management.  相似文献   
95.
The definition of the entropy of a cratered surface is given by analogy with the entropy of the information theory. The saturation, defined as the ratio between the area covered by craters of diameterD and the total observed area, is adopted as a measure of the probability to find a portion of a planetary surface covered by craters of the given diameterD.The meaning of such a new function is discussed in comparison with statistical approaches to the study of the cratering. Applications to Mercury are discussed.Paper presented at the European Workshop on Planetary Sciences, organised by the Laboratorio di Astrofisica Spaziale di Frascati, and held between April 23–27, 1979, at the Accademia Nazionale del Lincei in Rome, Italy.  相似文献   
96.
Antigorite polysomatism: behaviour during progressive metamorphism   总被引:4,自引:0,他引:4  
Antigorite forms a polysomatic series of discrete compositions that are chemographically colinear with chrysotile/lizardite, Mg3Si2O5(OH)4 and talc, Mg3Si4O10(OH)2. The compositional variations of antigorite correspond to discrete changes in the lattice parameter, a. A complete suite of antigorites, collected from a cross-section representing increasing metamorphic grade through the Swiss and Italian Alps, has been studied by optical and transmission electron microscopy (TEM). The specimens within this suite range from those formed near the lower stability limit of antigorite (250 °C) through to those formed near its breakdown temperature (550 °C). The lower grade samples belong to the regionally metamorphosed upper Pennine Ophiolites of the Oberhalbstein-Malenco area, while higher grade antigorites were obtained from regionally metamorphosed Malenco serpentinites. The highest grade samples are also from Malenco. They underwent a later contact metamorphism within the thermal aureole of the Bregaglia Intrusive. The lattice parameter a of antigorites evolves from longer (60 Å) to shorter (35 Å) values with increasing metamorphic grade. However, individual antigorites almost invariably show a heterogeneous distribution of a periodicities with higher values close to grain boundaries or reaction fronts and lower values towards the grain centers. The crystal-chemical evolution of antigorite, expressed by reduction in a, is usually accompanied by increased crystallinity. With the TEM, this is seen as an increase in crystallite size and a decrease in the number of crystal defects (twinning, polysomatic disorder, modulation dislocations, wobbling, offset). The structural and compositional evolution of antigorite requires intracrystalline diffusion and reconstructive transformations at relatively low temperatures. Therefore, the process of evolution is sluggish. Equilibrium is frequently not attained, and relics of longer a periodicities can be observed. In addition, relics of chrysotile may be observed in high-grade metamorphic rocks of the Malenco area, in which antigorite coexists with new-formed olivine. Only at one locality is there evidence of equilibrium: antigorite formed at 435 °C has a=43 Å; it shows very little variation in the a periodicity, and it is characterized by a homogeneous annealing texture. A geothermometer based upon a periodicities, as proposed by Kunze (1961) has limited practical applicability.  相似文献   
97.
Summary The crystal structure of låvenite (monoclinicP2 1 /a,a=10.83(1),b=9.98(1),c=7.174(5) Å, =108.1(1)o), was refined using 1743 independent reflections toR=0.032 andR w=0.036. The refined structure is in agreement with the structure model proposed bySimonov andBelov (1960), characterized by the presence of walls of large cation polyhedra. These walls are four columns large, linked together by both direct connection as well as by Si2O7 groups. The cation distribution inside the wall is explained and compared with that found in other phase of the cuspidine group. The crystal chemical formula resulting from structural and chemical analyses on låvenite from Langesund (Norway) is (Na6.50Ca1.47Y0.03) (Ca0.93 Mn1.26Fe 0.87 2+ Ti0.65Zr0.18Mg0.05) (Zr3.42Nb0.58) (Si2O7)4O3.82F3.98.
Verfeinerung der Kristallstruktur des Låvenits
Zusammenfassung Die Kristallstruktur des Låvenits (monoklinP2 1 /a,a=10,83(1),b=9,98(1),c=7,174(5) Å. =108,1(1)o) wurde mit 1743 unabhängigen Reflexen aufR=0,032 undR w=0,036 verfeinert.Die Verfeinerung bestätigt in wesentlichen Zügen das vonSimonov undBelov (1960) vorgeschlagene Strukturmodell, nämlich Bänder aus den Polyedern um die großen Kationen, die sowohl direkt als auch durch an den Polyedern hängende Si2O7-Gruppen miteinander verknüpft sind.Die Kationenverteilung in den Polyederbändern wurde aufgeklärt; es ergibt sich folgende kristallchemische Formel: (Na6,50Ca1,47Y0,03) (Ca0.93Mn1,26Fe 0,87 2+ Ti0,65Zr0,18Mg0,05) (Zr3,42Nb0,58) (Si2O7)4O3,82F3,98.


With 3 Figures  相似文献   
98.
The Cerro del Almirez ultramafic massif offers an example of high pressure and high temperature antigorite serpentinites. A sharp antigorite-out isograd separates them from Chl-harzburgites, consisting of olivine + enstatite + chlorite. Antigorite is characterized by aluminium contents as high as 4 wt.% Al2O3. The microstructural study shows that, prior to the transformation, antigorite is exceptionally ordered and consists of the polysome m = 17. No polysomatic defect occurs in antigorite forming most of the Cerro del Almirez serpentinites. Close to the antigorite-out isograd, limited disorder features may occur, mainly as (001) twins, reaction rims and reduction of m down to 14–15. Here, local recrystallization phenomena lead to sporadic growth of large antigorite and chlorite crystals.  相似文献   
99.
Volcanic gases give information on magmatic processes. In particular, anomalous releases of carbon dioxide precede volcanic eruptions. Up to now, this gas has been measured in volcanic plumes with conventional measurements that imply the severe risks of local sampling and can last many hours. For these reasons and for the great advantages of laser sensing, the thorough development of volcanic lidars has been undertaken at ENEA (Italian National Agency for New Technologies, Energy and Sustainable Economic Development). In fact, lidar profiling allows one to scan remotely volcanic plumes in a fast and continuous way, and with high spatial and temporal resolution. A differential absorption lidar instrument will be presented in this paper: BILLI (BrIdge voLcanic LIdar). It is based on injection-seeded Nd:YAG laser, double-grating dye laser, difference frequency mixing and optical parametric amplifier. BILLI is funded by the ERC (European Research Council) project BRIDGE (BRIDging the gap between Gas Emissions and geophysical observations at active volcanos). It scanned the gas emitted by Pozzuoli Solfatara (Naples, Italy) and Stromboli Volcano (Sicily, Italy) during field campaigns carried out from October 13 to 17, 2014, and from June 24 to 29, 2015, respectively. Carbon dioxide concentration maps were retrieved remotely in few minutes in the crater areas. To our knowledge, it is the first time that carbon dioxide in a volcanic plume is retrieved by lidar. This result represents the first direct measurement of this kind ever performed on active volcanos and shows the high potential of laser remote sensing in early detection of volcanic hazard.  相似文献   
100.
Ancient evaporite deposits are geological archives of depositional environments characterized by a long‐term negative precipitation balance and bear evidence for global ocean element mass balance calculations. Here, Cretaceous selenite pseudomorphs from western Anatolia (‘Rosetta Marble’) — characterized by their exceptional morphological preservation — and their ‘marine’ geochemical signatures are described and interpreted in a process‐oriented context. These rocks recorded Late Cretaceous high‐pressure/low‐temperature, subduction‐related metamorphism with peak conditions of 1·0 to 1·2 GPa and 300 to 400°C. Metre‐scale, rock‐forming radiating rods, now present as fibrous calcite marble, clearly point to selenitic gypsum as the precursor mineral. Stratigraphic successions are recorded along a reconstructed proximal to distal transect. The cyclical alternation of selenite beds and radiolarian ribbon‐bedded cherts in the distal portions are interpreted as a two type of seawater system. During arid intervals, shallow marine brines cascaded downward into basinal settings and induced precipitation. During more humid times, upwelling‐induced radiolarian blooms caused the deposition of radiolarite facies. Interestingly, there is no comparable depositional setting known from the Cenozoic world. Meta‐selenite geochemical data (δ13C, δ18O and 87Sr/86Sr) plot within the range of reconstructed middle Cretaceous seawater signatures. Possible sources for the 13C‐enriched (mean 2·2‰) values include methanogenesis, gas hydrates and cold seep fluid exhalation. Spatially resolved component‐specific analysis of a rock slab displays isotopic variances between meta‐selenite crystals (mean δ13C 2·2‰) and host matrix (mean δ13C 1·3‰). The Cretaceous evaporite‐pseudomorphs of Anatolia represent a basin wide event coeval with the Aptian evaporites of the Proto‐Atlantic and the pseudomorphs share many attributes, including lateral distribution of 600 km and stratigraphic thickness of 1·5 to 2·0 km, with the evaporites formed during the younger Messinian salinity crisis. The Rosetta Marble of Anatolia may represent the best‐preserved selenite pseudomorphs worldwide and have a clear potential to act as a template for the study of meta‐selenite in deep time.  相似文献   
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