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81.
A previous study aiming to characterize the water dynamics of a cloud forest in the Garajonay National Park (La Gomera) from measurements taken in a plot located in the upper part of a selected watershed within the park is here commented. Reported magnitudes of hydrological variables and conclusions based on them are in disagreement with those of numerous studies carried out previously at the same site. Large data dispersion and inapplicability of some of the hypothesis assumed are shown to invalidate most of the results. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
82.
Greenhouse gas emission mitigation plan for the State of Israel: strategies,incentives and reporting
Axel Michaelowa 《Climate Policy》2013,13(6):784-786
In the context of the negotiations under the United Nations Framework Convention on Climate Change and its accompanying Kyoto Protocol, participating nations have recognized the need for formulating Nationally Appropriate Mitigation Actions (NAMAs). These NAMAs allow countries to take into account their national circumstances and to construct measures to mitigate GHG emissions across economic sectors. Israel has declared to the UN that it would strive to reduce its GHG emissions by 20% in the year 2020 relative to a ‘business as usual' scenario. With its growing population and an expanding economy, the national GHG mitigation plan was developed to draw a course for steering the Israeli economy into a low-carbon future while accommodating continued economic growth. The article describes relevant policy measures, designed to aid in the implementation of the plan and compares them with measures being undertaken by different countries. Emphasis is placed on analysing the progress to date, opportunities and barriers to attaining the ultimate GHG emissions reduction goals. The objective of this article is to contribute to the knowledge base of effective approaches for GHG emissions reduction. We emphasize the integrated approach of planning and implementation that could be especially useful for developing countries or countries with economies in transition, as well as for developed countries. Yet, in the article we argue that NAMAs’ success hinges on structured tracking of progress according to emerging global consensus standards such as the GHG Protocol Mitigation Goals Standard.Policy relevance:The study is consistent with the NAMA concept, enabling a country to adopt a ‘climate action plan’ that contributes to its sustainable development, while enabled by technology and being fiscally sound.The analysis shows that although NAMAs have been framed in terms of projects, policies, and goals, current methodologies allow only the calculation of emission reductions that can be attributed to distinct projects. Currently, no international guidance exists for quantifying emissions reduction from policy-based NAMAs, making it difficult to track and validate progress. This gap could be addressed by an assessment framework that we have tested, as part of a World Resources Institute pilot study for an emerging voluntary global standard. 相似文献
83.
In this study a field‐sampling technique for dissolved hydrogen (H2) in groundwater will be presented which allows the transport of gaseous samples into the laboratory for further analysis. The method consists of transferring the headspace trapped in a gas‐sampling bulb which is continuously purged by groundwater into previously evacuated vials using a gas‐tight syringe. Three transfer steps with preceding evacuation of the vial led to a H2‐recovery of 100 % in laboratory experiments. The method has been applied to determine H2 concentrations in an aquifer contaminated with chlorinated solvents. Tests concerning the effect of different pumping techniques on H2 concentrations revealed that most reliable values were obtained with a bladder pump, while an electrically driven submersible pump generated considerable amounts of hydrogen due to electrochemical interactions with the sampled water. Concentrations of dissolved hydrogen in field and laboratory samples were about two orders of magnitude higher when sampling was performed with the electrically driven submersible pump compared to sampling with the bladder pump and a peristaltic pump. Lab experiments with a Plexiglas reservoir to produce H2‐enriched water were used to study the effect of two tubing materials (PVC, polyamide) on H2 losses. PVC tubing turned out to allow transfer of H2‐enriched water over 25 m without significant losses, while PA‐tubing was not suitable for sampling of H2. 相似文献
84.
Axel Plešinger 《Studia Geophysica et Geodaetica》1968,12(1):50-55
Приводится описание фотокомпенсационного усилителя на полупроводниках, предназначенного для усиления слабых выходных сигналов пассивных преобразователей геофизических величин. Шумовые помехи отнесенные к входу усилителя порядка 10?8 в или 10?10 а в диапазоне частот 0,01–20Гц. Описывается новый метод, который позволяет создать фотокомпенсационные усилители напряжения или тока с заранее заданными передаточными свойствами (заданной амплитудной или фазовой частотной характеристкой, заданным быстродействием и т.п.). Возможности использования этого метода демонстрируются на двух практических примерах. 相似文献
85.
Prof. Dr. Axel Von Hillebrandt 《International Journal of Earth Sciences》1970,59(3):1180-1203
Lower and Upper Cretaceous sediments were investigated in the Peruvian Central Cordillera. As in the western facies of Central and Northern Peru, the Goyllarisquisga Group is subdivided into several lithologically different formations, in which sediments were transported from east to west. The area of investigation is situated west of the facies boundary between Marañon geanticline and West Peruvian trough; this indicates that the boundary continues south and does not follow the line Celendin-Rio Palanga as suggested byWilson. The limestones and dolomites of the Santa Formation were deposited in shallow water, possibly with intermittent subaerial exposure. The sandstone of the Farrat Formation are interpreted to be sediments of a west-east transgression; vertically they grade into the limestones of the Pariahuanca-Formation. Facies and thickness of the Chulec and Pariahuanca-Formation are little different from those in neighbouring areas. During deposition of the thick Jumasha Formation, the differences are much more significant, and only comparison with Northwest Peru shows some agreement. 相似文献
86.
87.
The Chihuahua City region, located in the semiarid-arid northern highlands of Mexico, has experienced intensive groundwater abstraction during the last 40 years to meet water demands in the region. A geochemical survey was carried out to investigate the evolution from baseline to modern conditions of a 130-km flow path including the El Sauz–Chihuahua–Aldama–San Diego de Alcalá regions. The research approach included the use of major chemical elements, chlorofluorocarbons and environmental isotope (18O, 2H, 13C and 14C) tracers. Stable isotopes indicate that groundwater evolves from the evaporation of local rainfall and surface water. Groundwater located at the lower end of the flow section is up to 6000 years old and older groundwater in the order of 9000 years BP was found in a deep well located in the upper part of the flow system, implying contribution from a neighbour basin. The background groundwater chemistry upstream of Chihuahua City results from feldspar weathering. Beyond Chihuahua City the chemical conditions are strongly modified owing to disposal of sewage from public and industrial water supplies into the Rio Chuviscar, subsequent allocation of this water to agricultural irrigation areas and direct infiltration under the river bed. As a consequence, anions like chloride and sulphate are mainly related to surface sources. Nitrate is controlled in part by sewage from public supply and industry and in part by agricultural practices. Arsenic and fluoride are related to weathering of rock formations of local mineralized ranges and subsequent enrichment of the basin-fill by magmatic processes. The results of this study have implications for groundwater management in an arid region that depends entirely on groundwater for domestic, industrial and agricultural water consumption. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
88.
89.
90.
Nils Aall Barricelli 《Earth, Moon, and Planets》1982,27(2):179-185
A theory (Barricelli, 1972) developed for the interpretation of planetary axial rotations is here applied to an interpretation of the axial rotations of major asteroids. The interpretation is based on the assumption that also asteroids can have satellite-systems, which may influence the axial rotation of the respective primaries. The reason why smaller asteroids tend to have slower axial rotation than the major ones as an average is discussed. Predictions of the theory can be tested by space-craft exploration of asteroids. 相似文献