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21.
In this paper, tables for the trigonometric series representations of the orbital inclination functionF lmp (i) in multiples of cosines or sines will be represented forl=2(1)10;m=0(1)l;p=0(1)l.Astrophysics and Space Science Review Article.  相似文献   
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Landfill leachate comprises a complex mixture of contaminants many of which may have multiple sources in the environment confounding conventional techniques for apportioning sources. Compound specific isotope ratio mass spectrometry offers the potential to “fingerprint” compounds enabling discrimination to be made between different sources. This paper presents a rapid and highly reproducible method to prepare landfill leachate samples for compound specific isotope analysis. A suitable solid phase extraction (SPE) method was developed using artificial contaminant solutions, natural waters spiked with artificial contaminants (eucalyptol, dodecane, benzothiazole, dibutyl phthalate and naphthalene), and samples of landfill leachate. The elution of adsorbed compounds from the SPE cartridge was found to be the major cause of hydrogen and carbon isotope fractionation. Three different SPE cartridge types were tested: C18, Strata-X and ENV+. Fractionation of between 1‰ and 245‰ for hydrogen isotopes and 0–1.83‰ for carbon isotopes was observed. Part of the fractionation could be attributed to the different SPE cartridges but the major contribution was from the choice of the eluting solvent. Our results indicated hydroxylated styrene-divinylbenzene cartridges eluted with dichloromethane resulted in negligible hydrogen or carbon isotope fractionation for any of the tested organic compounds.The isotopic fractionation of hydrogen and/or carbon of most artificial contaminants were proportional to the efficiency with which they were extracted from water. Only naphthalene exhibited isotopic fractionation unrelated to its extraction efficiency but this fractionation was negligible.The comparative extraction of landfill leachate using SPE and LLE indicated SPE generally extracts slightly more of each compound from leachate than LLE. This relationship is stronger than for polar compounds. In addition, the δD composition of each compound prepared using SPE was with two standard deviations of the sample compound prepared using LLE, and the δ13C composition of each compound prepare using either method was mostly within two standard deviations.  相似文献   
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Stochastic Environmental Research and Risk Assessment - Coronavirus disease (COVID-19) is an inflammation disease from a new virus. The disease causes respiratory ailment (like influenza) with...  相似文献   
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The Newer Volcanics Province of south‐eastern Australia is often overlooked, though it comprises a multitude of volcanic features worthy of exploration. The province contains > 416 eruption centres varying in nature from simple to complex, ranging from lava shields and scoria cones to some of the largest maar volcanoes in the world. Explorable caves and lava tubes showcase well‐preserved lava flow features, while the province is a fossickers dream, containing abundant mantle xenolith and megacryst collecting localities. As the most recent eruption was ~5000 bp at Mt. Gambier, the Newer Volcanics is considered an active province, and may yet provide Australia with more eruptions, adding to the glorious volcanic features of the wonderful landscape.  相似文献   
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Ella Ödmann 《Geoforum》1973,4(1):31-41
Urbanisation is a functional change in land utilisation which requires a high degree of coordination in time and space. Swedish society has not considered it possible to entrust this coordination to the free market forces. A number of measures was introduced during the latter part of the sixties with a view to coordinating housing development by means of local authority-land ownership and preventing land speculation. In a recently published report of a Government Commission it is proposed that dwellings receiving Government housing loans (more than 90 % of building construction) shall only be built on land which is owned by the local authorities. The local authorities may then be assumed to be the only purchasers of land for housing development purposes. Their housing policy can be given a more short-term character and can be better adapted to urban planning. Urban development in Sweden during recent decades is characterised by a struggle between the two groups of our mixed-economy society, i. e., a social democratic government, and capitalistic enterprise. As far as the private individual is concerned, both parties are remote decision makers. The important question is whether an improvement in town environment may be expected before the private individual has been given a chance to influence planning. The relationship between housing development and land ownership in some Swedish towns over the period 1950–1970 is presented as an example of the realization of land policy.  相似文献   
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The adsorption of surfactants from aqueous solution is a phenomenon of major importance in applications ranging from ore flotation and paint technology to enhanced oil recovery. As this paper will illustrate, the process is very complex and of high scientific interest; its results can be extended to the retention of organic compounds (humic and fulvic acids, pollutants...) on solids in the biosphere. For a good understanding of the mechanisms involved in surfactants adsorption at the hydrophilic solid–aqueous solution interface, thermodynamic models have to take into account: (i) the physical chemistry of the surfactant in aqueous solution for choosing the appropriate reference phase, (ii) the surface heterogeneity of the adsorbing solid, (iii) the intensity of normal adsorbate–adsorbent bonds responsible for adsorption, (iv) the intensity of lateral bonds that favour the formation of surface aggregates through cooperative process and finally, (v) suitable theoretical models to describe adsorption phenomena. Once this has been achieved, two systems can be discussed: systems characterised by strong normal adsorbate–adsorbent bonds, currently used in ore flotation, which lead, in the case of heterogeneous surfaces, to the formation of lamellar aggregates at monolayer concentration and bilayer formation for higher concentrations. Systems characterised by weak normal adsorbate–adsorbent bonds, currently used in enhanced oil recovery and hydrocarbon (bio)remediation, which correspond to: (i) formation of globular micelles at the solid surface near the CMC when the temperature is higher than the Krafft point, (ii) formation of bilayered lamellar aggregates in the opposite case, (iii) three-dimensional condensation on substrate (T<TKrafft) if the ionic surfactant interacts with cations in the bulk. To cite this article: J.-M. Cases et al., C. R. Geoscience 334 (2002) 675–688.  相似文献   
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Horashim East is a newly discovered Middle Palaeolithic open-air occurrence in central Israel, revealed during a thematic prehistoric survey. Hundreds of lithic items were found, including an early-stage biface, Levallois cores and products. As only a few open-air settlements are known from the Middle Palaeolithic Levant, the discovery of Horashim East sheds new light on human land-use patterns during this period and reinforces the notion that central-eastern Israel was favourable for human settlement throughout the Palaeolithic.  相似文献   
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