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121.
Suresh Kumar N. R. Patel Aditi Sarkar V. K. Dadhwal 《Journal of the Indian Society of Remote Sensing》2013,41(3):609-618
The present study demonstrated the methodology to assess agro-climatic suitability of the soybean crop through integration of crop suitability based on FAO framework of land evaluation and biophysical (water limited) yield potential in the rainfed agro-ecosystem. A long term climatic database (1980–2003) was prepared to compute decadal rainfall and temperature variations of 13 IMD stations in part of Madhya Pradesh state. The climatic database was used in soil water balance software–BUDGET to compute crop specific length of growing period (LGP) and biophysical production potential such as water limited crop yield potential of each soil types for soybean crop. Water limited crop yield potential of soils were found to be varied from 33 to 100 and LGP ranged from 65 to 180 days in the area. FAO based land suitability was analyzed in association with the water limited yield potential for better appraisal of land potential and assess their suitability in rainfed area. FAO based land suitability indicated 2.45 % area as highly suitable and 57.49 % area as moderately suitable. However, integration of water limited crop yield potential with FAO based land suitability lead to agro-climatic suitability analysis indicated 17.60 % and 40.03 % area, respectively as highly suitable and moderately suitable. FAO based land evaluation showed 88.13 % of plains as moderately suitable whereas agro-climatic suitability indicated only 47.79 %. Agro-climatic suitability analysis revealed undulating plateau and undulating plains as most suitable for soybean crop. 相似文献
122.
Richard C. Ghail Colin Wilson Marina Galand David Hall Chris Cochrane Philippa Mason Joern Helbert Franck MontMessin Sanjay Limaye Manish Patel Neil Bowles Daphne Stam Jan-Erik Wahlund Fabio Rocca David Waltham Tamsin A. Mather Juliet Biggs Matthew Genge Philippe Paillou Karl Mitchell Lionel Wilson Upendra N. Singh 《Experimental Astronomy》2012,33(2-3):337-363
123.
Enrichments of New Zealand geo‐thermal samples, initiated in anaerobic sulphur‐containing media and incubated at temperatures above 85°C, yielded rod and coccal shaped organisms which possessed archaebacterial characteristics. Pure cultures were isolated and characterised. Five of the seven isolates, which were rod‐shaped organisms and did not have an obligate requirement for sulphur respiration, were similar to Thermoproteus sp. but had more neutral pH optima for growth. Three of these five Thermoproteus sp. were obligate heterotrophs, which has not previously been reported. The two coccal isolates had an obligate requirement for sulphur as an electron acceptor and were similar to Desulfurococcus sp. but again with more neutral pH optima for growth. 相似文献
124.
Nishith Y. Bhatt Satish J. Patel Dipal A. Patel Hardik P. Patel 《Journal of the Geological Society of India》2009,74(4):515-530
Behavioural activities of the goby fish-Periophthalmodon septemradiatus were observed in the intertidal zone around Navinal coast in the Gulf of Kachchh, western India. Intertidal zone is broad,
and comprise of creeks, which are muddy and vegetated by mangrove on eastern side and ridge runnel systems on western side
of the study area which are hospitable for the goby fish. Different types of biogenic activities are observed such as crawling,
pellet making, grazing and burrowing. The crawling activity is part of movement of the goby fish from one burrow to another
burrow and pellet making activity is part of burrow modification. The grazing activity is feeding on the surface mud after
receding of tide and exposure of the tidal flat by left and right movement of the front part of the body. The most conspicuous
activity is burrowing, they construct unlined, vertical to incline ‘I’, ‘J’ and ‘Y’ shaped branched, circular to oval burrows
with varying diameter and depth. In the muddy sediments goby fish produced circular to oval rimmed muddy lumps as surfacial
expression around the burrows and further produced funnel shape depression and downward extended cylindrical holes, while
in the runnels burrows are usually small and simple. The trail is consisting of fin marking on either side of the tail marks
(grooves) which are radiate around the burrows. Occasionally burrows are interconnected in more than one burrow system which
is nested within single funnel structure on the surface.
The burrow systems of the goby fish in the intertidal sediments serves for protection and dwelling purpose and most importantly
these burrows are irrigated by water which supply the oxygen and keep body surface wet. The overall dimensions of the burrow
decrease towards the lower intertidal zone. In all, behavioural structure produced by the goby fish marks the combined activity
of dwelling, feeding and grazing. The complex behavioural mechanisms have helped the goby fish to survive and flourish in
the harsh intertidal environments along the Navinal Coast, in the Gulf of Kachchh. 相似文献
125.
Dhosa Oolite Member of the Jumara Formation comprises alternating bands of oolitic limestones and shales, exposed in Jhura
dome of Mainland Kachchh, Western India. This sequence is highly bioturbated and exhibits a moderate diversity and behaviourally
complex assemblage of ichnospecies. The rhythmically bedded sequence shows three different levels of preservation of traces.
Epichnial tiering consists of moderately bioturbated oolitic limestone exhibiting horizontal or low-angle protrusive/retrusive
biogenic laminae, commonly dominated by feeding structures like Rhizocorallium jenense, R. irregulare, Zoophycos brianteus and Zoophycos isp. The endichnial structures within the oolitic limestone can be separated into two different preservational trace fossil
suites. The endichnial shallow suites consist chiefly of deposit feeders like Chondrites intricatus, C. targionii, Planolites beverleyensis, Taenidium cameronensis, Thalassinoides isp., Z. brianteus, Z. cf circinnatus and Zoophycos isp. and few suspension feeder forms like Palaeophycus tubularis; while endichnial deep suites consist of Chondrites intricatus, Skolithos linearis and Zoophycos isp. Hypichnial structures consists abundant, cylindrical, branched, horizontal, large-sized three dimensional feeding burrows
of Thalassinoides isp. and somewhat irregular, obtuse angle ramification burrows of Phycodes isp., which are attached to the lower surface of the casting medium. The trace fossil association indicates Cruziana ichnofacies and abundance of Zoophycus species below the fair weather wave base level is largely a preservational artifact. The preservational processes of the
trace fossils indicate soft substrate and diversity and their abundance reflects the other palaeoecological parameters of
the open shallow marine environments. 相似文献
126.
S.C. Patel S. Ravi Y. Anilkumar A. Naik S.S. Thakur J.K. Pati S.S. Nayak 《Journal of Asian Earth Sciences》2009,34(3):336-346
Mafic xenoliths of garnet pyroxenite and eclogite from the Wajrakarur, Narayanpet and Raichur kimberlite fields in the Archaean Eastern Dharwar Craton (EDC) of southern India have been studied. The composition of clinopyroxene shows transition from omphacite (3–6 wt% Na2O) in eclogites to Ca pyroxene (<3 wt% Na2O) in garnet pyroxenites. Some of the xenoliths have additional phases such as kyanite, enstatite, chromian spinel or rutile as discrete grains. Clinopyroxene in a rutile eclogite has an XMg value of 0.70, which is unusually low compared to the XMg range of 0.91–0.97 for all other samples. Garnet in the rutile eclogite is also highly iron-rich with an end member composition of Prp26.5Alm52.5Grs14.7Adr5.1TiAdr0.3Sps1.0Uv0.1. Garnets in several xenoliths are Cr-rich with up to 8 mol% knorringite component. Geothermobarometric calculations in Cr-rich xenoliths yield different P–T ranges for eclogites and garnet pyroxenites with average P–T conditions of 36 kbar and 1080 °C, and 27 kbar and 830 °C, respectively. The calculated P–T ranges approximate to a 45 mW m?2 model geotherm, which is on the higher side of the typical range of xenolith/xenocryst geotherms (35–45 mW m?2) for several Archaean cratons in the world. This indicates that the EDC was hotter than many other shield regions of the world in the mid-Proterozoic period when kimberlites intruded the craton. Textural and mineral chemical characteristics of the mafic xenoliths favour a magmatic cumulate process for their origin as opposed to subducted and metamorphosed oceanic crust. 相似文献
127.
Hrishikesh Samant Ashwin Pundalik Joseph D’souza Hetu Sheth Keegan Carmo Lobo Kyle D’souza Vanit Patel 《Journal of Earth System Science》2017,126(1):9
The Panvel flexure is a 150-km long tectonic structure, comprising prominently seaward-dipping Deccan flood basalts, on the western Indian rifted margin. Given the active tectonic faulting beneath the Panvel flexure zone inferred from microseismicity, better structural understanding of the region is needed. The geology of Elephanta Island in the Mumbai harbour, famous for the ca. mid-6th century A.D. Hindu rock-cut caves in Deccan basalt (a UNESCO World Heritage site) is poorly known. We describe a previously unreported but well-exposed fault zone on Elephanta Island, consisting of two large faults dipping steeply east–southeast and producing easterly downthrows. Well-developed slickensides and structural measurements indicate oblique slip on both faults. The Elephanta Island fault zone may be the northern extension of the Alibag–Uran fault zone previously described. This and two other known regional faults (Nhava–Sheva and Belpada faults) indicate a progressively eastward step-faulted structure of the Panvel flexure, with the important result that the individual movements were not simply downdip but also oblique-slip and locally even rotational (as at Uran). An interesting problem is the normal faulting, block tectonics and rifting of this region of the crust for which seismological data indicate a normal thickness (up to 41.3 km). A model of asymmetric rifting by simple shear may explain this observation and the consistently landward dips of the rifted margin faults. 相似文献
128.
Cylindrically symmetric inhomogeneous magnetized string cosmological model is investigated. The source of the magnetic field is due to an electric current produced along x-axis. F 23 is the only non-vanishing component of electromagnetic field tensor. To get the deterministic solution, it has been assumed that the expansion (θ) in the model is proportional to the eigen value σ 1 1 of the shear tensor σ j i . The physical and geometric properties of the model are also discussed in presence and absence of magnetic field. 相似文献
129.
SK Pathan VK Shukla RG Patel BR Patel KS Mehta 《Journal of the Indian Society of Remote Sensing》1991,19(2):95-112
Proper urban planning and effective implementation requires reliable urban land use statistics. In this context, satellite remote sensing data has been studied using both visual and digital techniques. A portable eight-band radiometer has been used to collect spectral signatures of surface features present in Ahmedabad city and its environs. Using these signatures a suitable approach employing visual and digital techniques has been developed for urban land use/sprawl mapping. Urban land-use maps of Ahmedabad city and its environs were prepared on 1:25,000 scale and for Ahmedabad Urban Development Authority Area on 1:50,000 scale using this methodology. It has been found that edge-enhancement techniques are useful to enhance the contrast among different urban land uses. Classification techniques such as MXL and Bayes classifiers are not successful in discriminating urban land uses. Tonal characteristics alongwith other elements of interpretation are required to classify urban land uses such as residential, industrial etc. Spatial distribution of various urban and uses and the space devoted to each urban land use has been brought out. 相似文献
130.
A computer simulation approach to modelling the structure,thermodynamics and oxygen isotope equilibria of silicates 总被引:1,自引:0,他引:1
Atul Patel Geoffrey D. Price Monica J. Mendelssohn 《Physics and Chemistry of Minerals》1991,17(8):690-699
We use an atomistic model to simulate the structure, lattice dynamics and thermodynamics of silicate minerals. Our approach uses the Born model of a solid, in which the interaction between atoms is described by an interatomic pair potential. We have extended the study of thermodynamics to its very limit by looking at the subtle reaction of oxygen isotope exchange. We have modelled equilibria involving the important metamorphic minerals; albite, diopside, forsterite, pyrope, quartz and wollastonite. The predicted structural and thermodynamic data for these silicates are in very good agreement with the observed values. In addition, we predict not only the correct direction for the phase equilibria for oxygen isotope exchange, but also fractionation factors for the reaction to within a factor of two of the available experimental data. Hence, the potentials used in our approach have shown excellent transferability and have performed very well against the most stringent of tests. 相似文献