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91.
92.
József Nemes Nagy 《GeoJournal》1994,32(4):363-368
Disparities in Hungary can be characterized regionally with the dualism of Budapest and the countryside, with the western and eastern division of the country itself, with local crises of the broken down industrial axis and marginal geographic settings, with the differentation according to the hierarchy and size of settlements. Two thirds of the total foreign capital invested in Hungary and half of the joint ventures are concentrated in the capital. Apart from Budapest, it causes a higher unemployment rate and lower taxable incomes. 相似文献
93.
94.
Under communism local authorities tended to be largely passive bystanders in a regional development process which emerged
through the central planning process through the spatial allocations of investment by government ministries. Attention was
given to physical planning, but comparatively little material entered the public domain on location policy and spatial priorities
generally, apart from the objective of greater equality between regions and a commitment to backward areas generally. Now
that much investment is down to private enterprise and government has become more decentralised and accountable, there is
a need for concepts and strategies to coordinate public sector investment and provide guidelines for the evaluation of private
development proposals. At the same time, there is an open competition for investment which requires communities to promote
themselves in terms of their identity and development potential. This paper offers an overview by taking two countries - Hungary
and Romania - where progress can be compared and where the focus can be placed on a common frontier which is diverting attention
from conventional regional planning to cross-border cooperation. In both contexts however, attention is given to the ways
in which planning can divert investment away from the main centres to the peripheral areas, including action to strengthen
the role of small towns and also to improve cohesion among functionally-related groups of settlements and communes.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
95.
The dynamical structure of the orbital element space of seven Kuiper Belt binary systems is studied by numerical methods in the model of the spatial elliptic restricted three‐body problem. It is shown that three systems have an extended region of stability where additional satellites could exist. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
96.
The gravitational potential and its derivatives for the prism 总被引:24,自引:12,他引:12
As a simple building block, the right rectangular parallelepiped (prism) has an important role mostly in local gravity field
modelling studies when the so called flat-Earth approximation is sufficient. Its primary (methodological) advantage follows
from the simplicity of the rigorous and consistent analytical forms describing the different gravitation-related quantities.
The analytical forms provide numerical values for these quantities which satisfy the functional connections existing between
these quantities at the level of numerical precision applied. Closed expressions for the gravitational potential of the prism
and its derivatives (up to the third order) are listed for easy reference.
Received: 18 August 1999 / Accepted: 15 June 2000 相似文献
97.
At the global scale, the population density of coastal areas is nearly three times that of inland areas, and consequently, land development represents a threat to coastal ecosystems. It is critical to understand how increasing urbanization affects coastal watersheds. To that end, the objective of this study was to examine the influence of urban development on stream water quality and hydrology in a coastal setting, a scenario that has received less attention than other physiographic regions. Stream hydrologic, physicochemical, and microbial data were collected in watersheds near Apalachicola, Florida with a range of impervious surfaces from 0 to 15%. Watersheds with greater impervious cover exhibited higher pH, specific conductance, and temperature, elevated nutrient concentrations and loads (, and total phosphorus), higher bacterial concentrations (fecal coliform and Escherichia coli), and increased maximum flow and hydrograph flashiness. Different responses to development here compared to other physiographic regions included lower total suspended solid concentrations, higher total dissolved solid concentrations, and a lack of response of base flow to increased urbanization. Additionally, Na+ and Cl? concentrations were elevated to a greater extent than is often the case in non‐coastal areas. In the coming years, urban development is projected to increase substantially in coastal zones and thus there is risk of further stream degradation in coastal watersheds. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
98.
B.N. Khare Carl Sagan John E. Zumberge Deborah S. Sklarew Bartholomew Nagy 《Icarus》1981,48(2):290-297
The complex dark brown solid of a class called tholins, produced on passage of an electrical discharge through a roughly equimolar mixture of methane and ammonia with 2.6% water vapor, is analyzed by vacuum pyrolysis followed by gas chromatography and mass spectrometry. Pyrolyzates include a wide range of aliphatic and aromatic nitriles, alkanes, aromatic hydrocarbons, pyrrole, and pyridine. This tholin is remarkably stable to 950°C. It and its degradation products are candidate constituents of planetary aerosols in the outer solar system and of the grains in the interstellar medium. 相似文献
99.
A series of experiments have been conducted with polyethylene and polystyrene standards in an attempt to define the advantages and limitations of a vacuum pyrolysis—gas chromatography—mass spectrometry procedure for the characterization of kerogen and other macromolecular substances. Effects of variations in pyrolysis temperatures and times, sample sizes (weights) and thickness were evaluated together with the reproducibility of the nature and abundances of pyrolyzates. The effects of minerals (illite and quartz) admixed in the polymers were also considered with reference to the nature of the breakdown products. Optimal pyrolysis conditions, where primary pyrolyzates were sufficiently abundant and secondary products did not hinder characterization, were attained at 450°C and 60–90 min. The reproducibility of the nature and quantities of pyrolyzates was rather satisfactory at this temperature and pyrolysis time. However, relatively large samples of macromolecular matter, which is considerably volatile at this temperature, led to the synthesis of an abundant yield of secondary products, but sample thickness does not affect the nature of pyrolyzates. Admixed mineral matter affected the nature and relative abundances of the pyrolyzates but did not impede characterization of samples, as primary breakdown products were discernible. Macromolecular substances of limited volatility, heterogeneous chemical composition and containing intractable mineral matter, such as many kerogens, need to be pyrolyzed as relatively large samples. The vacuum procedure used in these studies may be to advantage, as compared with some other methods, to pyrolyze such samples. This method seems to be also suitable for the pyrolysis of volatile macromolecular matter, provided that small samples are employed. 相似文献
100.
Bartholomew Nagy 《Precambrian Research》1981,14(2):183-184