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1.
2.
The Jason-1 sea state bias (SSB) is analyzed in depth from the first year of GDR products. Compared to previous missions, this work benefits from two aspects of the empirical determination of the SSB from the altimetric data themselves. First, from a methodological point of view, a nonparametric technique (NP) has been developed and largely tested on TOPEX/Poseidon 1, GFO and Envisat data. The NP estimator has proven to be a useful tool in the SSB estimation, and it is now mature enough to be used for a refined analysis. On the other hand, the SSB can be extracted from three different data sets (crossovers, collinear data, and residuals) with different characteristics. It is then possible to cross calibrate various estimations of the SSB models and to determine the most accurate one. A systematic comparison is made between these different estimates for the Jason-1 altimeter. The collinear and crossover data sets yield very similar estimates despite their difference of spatial and temporal distributions. These SSB models assure consistency with the TOPEX mission when comparing Jason-1 and TOPEX residuals during the tandem phase. Thanks to the present work, the impact of the short wavelengths filtering on the SSB estimation is evidenced. More generally, our understanding of potential errors affecting the sea surface height and their impact onto the SSB estimation is also improved.  相似文献   
3.
Boron, chloride, sulfate, δD, δ18O, and 3H concentrations in surface water and groundwater samples from the Sulphur Bank Mercury Mine (SBMM), California, USA were used to examine geochemical processes and provide constraints on evaporation and groundwater flow. SBMM is an abandoned sulfur and mercury mine with an underlying hydrothermal system, adjacent to Clear Lake, California. Results for non-3H tracers (i.e., boron, chloride, sulfate, δD, and δ18O) identify contributions from six water types at SBMM. Processes including evaporation, mixing, hydrothermal water input and possible isotopic exchange with hydrothermal gases are also discerned. Tritium data indicate that hydrothermal waters and other deep groundwaters are likely pre-bomb (before ~1952) in age while most other waters were recharged after ~1990. A boron-based steady-state reservoir model of the Herman Impoundment pit lake indicates that 71–79% of its input is from meteoric water with the remainder from hydrothermal contributions. Results for groundwater samples from six shallow wells over a 6–month period for δD and δ18O suggests that water from Herman Impoundment is diluted another 3% to more than 40% by infiltrating meteoric water, as it leaves the site. Results for this investigation show that environmental tracers are an effective tool to understand the SBMM hydrogeologic regime.

Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Résumé Les concentrations en bore, chlorure, sulfate, δD, δ18O, et 3H d’échantillons d’eaux de surface et souterraine prélevés dans le banc de soufre de la mine de mercure (SBMM en anglais) en Californie, USA, ont été utilisées pour étudier les processus géochimiques et pour fournir des contraintes à l’évaporation et à l’écoulement des eaux souterraines. La SBMM est une mine de soufre et de mercure abandonnée, adjacente au lac Clear en Californie et sous laquelle se trouve un système hydrothermal.Les résultats des traceurs autres que le tritium (bore, chlorure, sulfate, δD, et δ18O) ont permis d’identifier des contributions de six types d’eaux à SBMM. Des processus tels que l’évaporation, le mélange, l’entrée d’eau hydrothermale et de possibles échanges isotopiques avec des gaz hydrothermaux ont également été identifiés. Les données de tritium montrent que les eaux hydrothermales et d’autres eaux profondes sont probablement d’age antérieure à la bombe (avant ~1952), alors que la plupart des autres eaux sont issues de la recharge après ~1990. Un modèle de réservoir représentant le lac situé dans la partie Herman Impoundment de l’ancienne mine, en régime permanent et basé sur le bore, montre que 71–79% de l’eau provient des précipitations, le reste provenant de contributions hydrothermales. Les résultats de δD et δ18O pour des échantillons d’eau souterraine de six puits peu profonds sur une période de 6 mois suggèrent que l’eau de Hermann Impoundment est encore diluée entre 3% jusqu’à plus de 40% lorsqu’elle quitte le site du fait de l’infiltration d’eau météorique. Les résultats de cette étude montrent que les traceurs environnementaux constituent un outil efficace pour comprendre le régime hydrogéologique de la SBMM.

Resumen Se han utilizado datos de concentraciones de boro, cloruros, sulfatos, δD, δ18O, y 3H en muestras de aguas superficiales y subterráneas procedentes de la Mina de Mercurio Sulphur Bank (SBMM), California, USA, para estudiar los procesos geoquímicos y caracterizar la evaporación y el flujo del agua subterránea. SBMM es una mina abandonada de azufre y mercurio con un sistema hidrotermal subyacente, cercano al Lago Clear, California.Los resultados de los trazadores que no son 3H (por ejemplo, boro, cloruros, sulfatos δD, y δ18O) identifican las contribuciones de seis tipos de agua en la SBMM. Se han identificado diversos procesos, como evaporación, mezcla, entrada de agua hidrotermal y la posibilidad de intercambios isotópicos con gases hidrotermales. Los datos de tritio indican que las aguas hidrotermales y otras aguas subterráneas profundas son probablemente pre-bombas (previas a ~1952) en edad mientras que la mayoría de las otras aguas se han recargado después de ~1990. Un modelo estacionario basado en el boro de la fosa del lago Herman Impoundment indica que el 71–79% de su entrada procede de agua meteórica con restos de contribución hidrotermal. Los resultados para las muestras de aguas subterráneas procedentes de seis pozos superficiales en un periodo de 6 meses para δD y δ18O sugieren que el agua procedente de Herman Impoundment se diluye en otro 3% hasta más del 40% debido a la infiltración de agua meteórica., que sale del sitio. Los resultados de esta investigación muestran que los trazadores ambientales son una herramienta efectiva para entender el régimen hidrogeológico de la SBMM.
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4.
We present a relatively completeV-band light curve of SZ Psc for 1978 and a partial light curve for 1977. From the 1978 light curve we derive a new time of primary minimum, JD2443823.674±0.001, and a Russell-model solution,i=75°.8±0°.1,r h =0.096±0.003,r c =0.351±0.001, andL h =0.253±0.002. The hotter component of this system is a F5-8 main-sequence star, the cooler component a K3-4 star well above the main sequence. The system is detached with the larger component filling only 82% of its Roche lobe. The distortion wave in this RS CVn-type binary seems not to migrate regularly as do those in many other such systems, but rather seems to change phase and amplitude more erratically. Between 1977 and 1978 its phase stayed practically constant while its amplitude decreased by a factor of three. We discuss the implications of this behavior for the spot model of RS CVn-type activity. We find that the traditional comparison star for SZ Psc, HD 219018, is very likely a constant star contrary to a recent suggestion that it is variable. Its brightness and colors,V=7.705, (B-V)=0.628, and (V-I) c =0.688, are those of a G2V star.Visiting Astronomer, Kitt Peak National Observatory, which is operated by AURA, Inc., under contract with the National Science Foundation, and Visiting Astronomer, Prarie Observatory, University of Illinois.  相似文献   
5.
Stepwise pyrolysis-gas chromatography is used to examine and characterize the carbonaceous matter in sedimentary rocks. Low-temperature steps remove material normally volatile or extracted by benzene-methanol. Successively-higher temperature steps degrade the insoluble carbonaceous matter (kerogen) into smaller molecular pieces. The sequential pyrolysis steps have the advantage of breaking the kerogen at several temperatures which may be related to bond type or strength. The pyrolysis product chromatograms from each step can be compared. The molecular sizes (chain length) of kerogens fragments can be determined. The results presented here show the molecules in the range C11 to C23 because: (1) they can be compared to normal petroleum source rock extractables; and (2) these large molecules give a feeling for the molecular construction of the kerogen.Green River and Antrim shales show low-temperature material which is indigenous and not modified compared to the pyrolyzed kerogen fragments in the range C11C23. Kupferletten shows low-temperature material of a narrow molecular weight range of C15C19 which is probably derived from the kerogen. Monterey shale low-temperature material appears to be unrelated to the kerogen as represented by its pyrolysis products. The Pierre shale kerogen shows molecules over the range C11C23. Kerogen from the Romney shale has no molecules large than C8 in its pyrolysis products and no petroleum potential due to thermal and tectonic diagenesis.  相似文献   
6.
7.
The spatial variability of long-term chemical weathering in a small watershed was examined to determine the effect of landscape position and vegetation. We sampled soils from forty-five soil pits within an 11.8-hectare watershed at the Hubbard Brook Experimental Forest, New Hampshire. The soil parent material is a relatively homogeneous glacial till deposited ∼14,000 years ago and is derived predominantly from granodiorite and pelitic schist. Conifers are abundant in the upper third of the watershed while the remaining portion is dominated by hardwoods. The average long-term chemical weathering rate in the watershed, calculated by the loss of base cations integrated over the soil profile, is 35 meq m−2 yr−1—similar to rates in other ∼10 to 15 ka old soils developed on granitic till in temperate climates. The present-day loss of base cations from the watershed, calculated by watershed mass balance, exceeds the long-term weathering rate, suggesting that the pool of exchangeable base cations in the soil is being diminished. Despite the homogeneity of the soil parent material in the watershed, long-term weathering rates decrease by a factor of two over a 260 m decrease in elevation. Estimated weathering rates of plagioclase, potassium feldspar and apatite are greater in the upper part of the watershed where conifers are abundant and glacial till is thin. The intra-watershed variability across this small area demonstrates the need for extensive sampling to obtain accurate watershed-wide estimates of long-term weathering rates.  相似文献   
8.
Flow-through dissolution experiments were carried out on crushed granitoid rock (the Elat Granite) and three mineral separates (plagioclase, perthite, and biotite + chlorite) from this rock at pH 1 and 25°C. Major element concentrations were combined with Pb and Sr isotopic analyses of starting materials and output solutions and together enabled us to elucidate several important mechanisms related to granitoid rock weathering. We observed an initial stage of rock dissolution (<200 hours of reaction) that was characterized by elemental release from traces of calcite and/or apatite and to a lesser extent from the interlayer sites of biotite. Dissolution in the interval of 200 to 400 h was dominated by the release of elements from the interlayer sites of biotite, and at 400 to 1000 h of reaction the chemistry of output solutions was dominated by the release of elements from tetrahedral and octahedral sites of biotite as well as from plagioclase. After 1000 h, the dissolution of plagioclase, and to a lesser extent biotite, dominated the composition of elements released by the rock. We demonstrate that Pb and Sr isotope ratios in the output solutions can be used to identify each of these stages of dissolution. By comparing our experimental results on the release of Pb and Sr isotopes with field measurements of Pb and Sr isotopes in soil chronosequences from the Wind River and the Sierra Nevada Mountains (USA), we are able to show that similar isotopic patterns appear in both the pH 1 experiments and in soils formed under natural conditions at higher pH. By combining these experimental results with previous field studies, we are able to estimate the duration of most of these stages of granitoid weathering under natural conditions in temperate climates. In soils older than a few hundred years and younger than 10,000 yr the release of elements from interlayer sites of biotite controls the weathering flux. Soils between 10,000 and 100,000 yr old are dominated by biotite and plagioclase weathering, with biotite weathering controlling the first part of this period and plagioclase dominating the later part. After more than 100,000 yr, plagioclase, and to a lesser degree biotite, dominate the weathering flux within these granitoid soils.  相似文献   
9.
Although the Sasebo, Japan harbor is usually a “typhoon haven” from tropical cyclone (TC) winds due to terrain-blocking effects, in rare cases damaging winds occur that may be attributed to terrain channeling. An empirical parametric model technique is developed and tested that includes consideration of the TC wind structure, land frictional effects, and terrain influences affecting the maximum wind speeds in the harbor when TCs pass within 200 nautical miles of Sasebo. The terrain influence is represented by two sets of wind direction-dependent acceleration factors. The first set, which is directly from the ratio of the local wind to the adjusted parametric wind for TCs passages during 2003–2010, provides mean values that represent the terrain blocking and channeling effects, but the variability with wind direction may be suspect. The second set derived from a large sample of reanalysis winds not limited to TCs has better variability properties, but is not easily related to just the TC passages. A new nomogram modified to include TC wind structure has higher estimates of Sasebo sustained winds for some TC tracks that may be related to terrain influences, but is limited due to the number of TC structure estimates in the developmental sample. These empirical models have the advantage of ease and low cost for future use in also estimating the combined uncertainty in the local winds in Sasebo harbor due to TCs.  相似文献   
10.
本文资料是国际矿物学协会新矿物及矿物命名委员会提供的,以资矿物学家在新矿物研究工作中参考和对比.CNMMN鼓励其成员将本文其所在国家的有关刊物发表.  相似文献   
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