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391.
Abstract

Conflicts in the management of renewable natural resources are situations in which actors have diverging opinions on issues of natural resource use. In the literature, among the causal factors for conflicts discussed are resource wealth or scarcity and the role of governance. The evidence, however, is contradictory. In order to analyze the role of governance in more detail, we propose a combined analysis of property rights and conflicts. In this way, an improved understanding of the causes of local conflicts over renewable natural resources can be achieved. We use comparative case study data from pasture management in the Caucasus region, first, to classify conflicts according to the bundle of property rights approach and, second, to explore how the causal factors resource scarcity and current governance contribute to those conflicts.  相似文献   
392.
Multiple-point statistics are widely used for the simulation of categorical variables because the method allows for integrating a conceptual model via a training image and then simulating complex heterogeneous fields. The multiple-point statistics inferred from the training image can be stored in several ways. The tree structure used in classical implementations has the advantage of being efficient in terms of CPU time, but is very RAM demanding and then implies limitations on the size of the template, which serves to make a proper reproduction of complex structures difficult. Another technique consists in storing the multiple-point statistics in lists. This alternative requires much less memory and allows for a straightforward parallel algorithm. Nevertheless, the list structure does not benefit from the shortcuts given by the branches of the tree for retrieving the multiple-point statistics. Hence, a serial algorithm based on list structure is generally slower than a tree-based algorithm. In this paper, a new approach using both list and tree structures is proposed. The idea is to index the lists by trees of reduced size: the leaves of the tree correspond to distinct sublists that constitute a partition of the entire list. The size of the indexing tree can be controlled, and then the resulting algorithm keeps memory requirements low while efficiency in terms of CPU time is significantly improved. Moreover, this new method benefits from the parallelization of the list approach.  相似文献   
393.
We conducted a study that shows that light and dark conditions do not affect the uptake rates of ammonium and nitrate by the seagrass Zostera noltei. This is an important advantage over some seaweed species in which these rates are severely reduced at night. In the light, the ammonium uptake rates were initially higher (15 and 20 μmol·g?1·h?1) and stabilized at a rate of 5 μmol·g?1·h?1 after 1 h, whereas in the dark the rates remained constant at a rate of 10 μmol·g?1·h?1 over the first 180 min of incubation. The rates of nitrate uptake in the light were high within the first 120 min of incubation (7.2–11.1 μmol·g?1·h?1) and decreased afterwards to lower values (0.8–3.9 μmol·g?1·h?1), whereas in the dark the rates fluctuated around 0.0–11.1 μmol·g?1·h?1 throughout the whole incubation time (7 h). The soluble sugar content of Z. noltei leaves increased significantly with both ammonium and nitrate incubations in the light, indicating the metabolic outcome of photosynthesis. In the dark, there was no significant variation in either the soluble sugar or in the starch content of leaves, rhizomes or roots in either the ammonium or nitrate incubations. However, the total starch content of plants decreased at night whereas the total soluble sugars increased, suggesting a process of starch catabolism to generate energy with the consequent production of smaller monosaccharide products. The starch content of rhizomes decreased significantly during the light incubations with nitrate but not with ammonium. These results suggest that carbohydrate mobilization is necessary for Z. noltei to account for extra energetic costs needed for the uptake and assimilation of nitrate. Furthermore, our results suggest that nitrate uptake, at least during the day, requires the mobilization of starch whereas the uptake of ammonium does not.  相似文献   
394.
We analyze the high-resolution dilatation data for the October 2013 \(M_w\) 6.2 Ruisui, Taiwan, earthquake, which occurred at a distance of 15–20 km away from a Sacks–Evertson dilatometer network. Based on well-constrained source parameters (\(\hbox {strike}=217^\circ \), \(\hbox {dip}=48^\circ \), \(\hbox {rake}=49^\circ \)), we propose a simple rupture model that explains the permanent static deformation and the dynamic vibrations at short period (\(\sim \)3.5–4.5 s) for most of the four sites with less than 20 % of discrepancies. This study represents a first attempt of modeling simultaneously the dynamic and static crustal strain using dilatation data. The results illustrate the potential for strain recordings of high-frequency seismic waves in the near-field of an earthquake to add constraints on the properties of seismic sources.  相似文献   
395.
The Myra mine, now inactive, produced Zn and Cu concentrates from a Zn-rich, Kuroko-type, volcanogenic massive sulfide deposit located in the mountainous interior of Vancouver Island. The climate at the site is classified as “Marine West Coast”, with annual precipitation exceeding 2200 mm. Water from a losing stream on the mountainside above the mine follows preferential, fracture-controlled pathways to the upper workings before draining through the 10-Level portal. With a view toward mine decommissioning, portal discharge rate was monitored continuously over a 17-month period during which 46 water samples were collected. Effluent chemistry, dominated by Ca, HCO3 and SO4, shows moderate to high total base metal concentrations and near-neutral pH. Carbonatization, mainly of mafic rocks in the hangingwall, provides significant acid neutralizing potential. Metal concentrations vary seasonally, with smaller spikes associated with summer storm events, and a main peak associated with flushing of the workings during the first heavy autumn rains. Aqueous speciation modeling suggests that Fe and Al concentrations are controlled by the solubilities of hydrous ferric oxides and microcrystalline gibbsite, respectively. Concentrations of Zn, Cu and Cd appear controlled by sorption rather than by the solubilities of mineral phases. A comparison of precipitate concentrations observed in portal effluent with predictions from mass balance (inverse) modeling results suggests that less than 5% of the precipitated Fe and Al hydroxides are transported from the mine. However, amounts of sorbed Cu, Zn and Cd measured in the effluent are only slightly lower than modeled values. This suggests that the small fraction of (probably finer) Fe precipitates in portal effluent sorbs most of the Zn, Cu and Cd predicted by modeling. Based on mass balance calculations, metal loadings are explained by the oxidation of 3830 kg of pyrite, 600 kg of sphalerite and 190 kg of chalcopyrite, annually. Circum-neutral drainage conditions are maintained by the reaction of almost 19,800 kg of calcite, annually.  相似文献   
396.

This paper presents an analysis of two large rock toppling/sliding events which occurred in January 2014 and February 2019 at the Cliets unstable slope (Savoie, French Alps). To understand the mechanism involved and its control by external forcings, a multi-technique analysis approach is used combining geological observations, meteorological data analysis, topographic measurements and simple physical modeling. The pre-failure stage of the events is more particularly analyzed. No direct relationships are found between triggering factors and surface motion though a kinematics analysis highlights the transition toppling-sliding. It showed that, at first order, this transition occurred 4 years before the first failure of 2014, while it happened 2 months before the second failure of 2019. From this date, the environment is considered like a block sliding on an inclined plane. By applying a frictional model (Helmstetter et al. in Journal of Geophysical Research: Solid Earth 109(B2), 2004), we illustrated that the two events belong to an unstable velocity-weakening sliding regime. The time to failure (Voight in Science 243(4888):200–203, 1989) is forecasted with the model, and the results are consistent with the observations. They confirm that the gravitational factor is predominant over the triggering factors for the two events.

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