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51.
Maciej Winiarski 《Earth, Moon, and Planets》1989,47(2):193-215
The paper contains results of three-colour photographic observations of positions and brightness of the cloud in the vicinity of the Earth-Moon libration point L5. The real character of the images obtained is confirmed by an agreement of their positions on different plates exposed at the same time. The colours of the cloud obtained are essentially different from those of the counterglow. The clouds appeared to be much redder than the counterglow, which may indicate that the particles constituting them are of different nature than those causing the counterglow. 相似文献
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The purpose of the research was to determine parameters of ground-motion models for two areas characterized by considerable
induced seismicity and different geology. Fifty-nine events collected from surface seismological stations of coal mine “Bielszowice”
(at the Main Anticline, South Poland) and 144 events from coal mine “Ziemowit” (at the Main Syncline, South Poland) were used
for computation. For both areas, simple ground-motion prediction equations (GMPEs) without site effects were derived, but
the model was acceptable only for “Bielszowice” area. The GMPE was calculated once again for “Ziemowit”, but this time we
took into consideration the amplification coefficient, which significantly improved the model solution. Finally, the theoretical
value of amplification was calculated. Knowing that the amplification is associated with subsurface layers, we used three
different models of overburden: (i) with Quaternary sediments only, (ii) with a complex of Quaternary-Tertiary sediments,
and (iii) with a complex of Quaternary-Tertiary-Triassic sediments and Carboniferous as a basement. Usually, the amplification
of vibrations appears in the Quaternary sediments. However, theoretical calculations of amplification were consistent with
the results obtained from GMPE when a rigid Carboniferous substratum was applied. 相似文献
55.
Sergey Dolomatov Walery Zukow Maciej Dzierzanowski Jan Mieszkowski Radoslaw Muszkieta Mariusz Klimczyk 《Water Resources》2016,43(1):177-183
The paper reviews scientific and practical aspects of research on the metabolism of nitrates into nitrate (nitrite) reductase in the nitric oxide cycle in fish under hypoxic conditions. Literature data are given about enzymes involved in nitrate reductase reactions and how oxygen shortage affects their activity. The environmental factors that may participate in the processes of nitrate reduction to nitrites as well as the ones which may influence the kinetics of nitrate in fishes are considered. Examined results indicate that certain components of the conservative L-arginine-dependent nitric oxide cycle pass in a number of vertebrate animals. Then, the contour cycle of nitric oxide in the fish shows a wide range of diversity which is represented by phylogenetically ancient biochemical mechanisms of nitrite (nitrate) reductase. First of all, the presence or absence of hemoglobin is distinguished. Secondly, a wider range of expression of different myoglobin isoforms appears. Furthermore, the kinetics of nitrates in fish is distinctly dependent on abiotic environmental factors. The analysis of the literature confirms the thesis that nitrates are an important substrate for the nitrate (nitrite) reductase loop cycle of nitric oxide in fishes. Secondly, their role in the compensation of arginineindependent NO synthesis increases with decreasing oxygen levels in the environment. Thirdly, the provided research results are a basis for indicating xanthine oxidase and possibly the microflora of the digestive system as the basic units of the nitrate reductase system in the body of fish. The practical aspect of the question, in our opinion, is the most meaningful presence of numerous studies that emphasize the need to find physiological reactions that precede the formation of pathological changes induced by the influence of combined effects of nitrates and hypoxia on the organism of fish. 相似文献
56.
Secondary Ion Mass Spectrometry Bias on Isotope Ratios in Dolomite–Ankerite,Part I: δ18O Matrix Effects 下载免费PDF全文
Maciej G. Śliwiński Kouki Kitajima Reinhard Kozdon Michael J. Spicuzza John H. Fournelle Adam Denny John W. Valley 《Geostandards and Geoanalytical Research》2016,40(2):157-172
We document the development of a suite of carbonate mineral reference materials for calibrating SIMS determinations of δ18O in samples with compositions along the dolomite–ankerite solid solution series [CaMg(CO3)2–CaFe(CO3)2]. Under routine operating conditions for the analysis of carbonates for δ18O with a CAMECA IMS 1280 instrument (at WiscSIMS, University of Wisconsin‐Madison), the magnitude of instrumental bias along the dolomite–ankerite series decreased exponentially by ~ 10‰ with increasing Fe content in the dolomite structure, but appeared insensitive to minor Mn substitution [< 2.6 mol% Mn/(Ca+Mg+Fe+Mn)]. The compositional dependence of bias (i.e., the sample matrix effect) was calibrated using the Hill equation, which relates bias to the Fe# of dolomite–ankerite [i.e., molar Fe/(Mg+Fe)] for thirteen reference materials (Fe# = 0.004–0.789); for calibrations employing either 10 or 3 μm diameter spot size measurements, this yielded residual values ≤ 0.3–0.4‰ relative to CRM NBS 19 for most reference materials in the suite. Analytical precision was ± 0.3‰ (2s, standard deviations) for 10‐μm spots and ± 0.7‰ (2s) for 3‐μm spots, based on the spot‐to‐spot repeatability of a drift monitor material that ‘bracketed’ each set of ten sample‐spot analyses. Analytical uncertainty for individual sample analyses was approximated by a combination of precision and calibration residual values (propagated in quadrature), suggesting an uncertainty of ± 0.5‰ (2s) for 10‐μm spots and ± 1‰ (2s) for 3‐μm spots. 相似文献
57.
Karolina Kośmińska Jarosław Majka Stanisław Mazur Michael Krumbholz Iwona Klonowska Maciej Manecki Jerzy Czerny Maciej Dwornik 《地学学报》2014,26(5):377-386
Recent fieldwork in Nordenskiöld Land, Svalbard's Southwestern Basement Province, has established the presence of high‐pressure (HP) lithologies. They are strongly retrogressed blueschists consisting mainly of garnet and Ca‐amphibole with remnants of ferroglaucophane and phengite. The pressure–temperature (P–T) conditions were estimated using phase equilibrium modelling in the NCKFMMnASHTO system. P–T estimates based on the garnet, phengite and ferroglaucophane compositional isopleths and modelled paragenetic assemblage indicate peak metamorphism at 470–490 °C and 14–18 kbar. These data fall close to the 7–8 °C km?1 geotherm, which is similar to that from Motalafjella, the only previously known occurrence of blueschists in Svalbard's Caledonides. The newly discovered blueschists could have formed during the early stage of the Caledonian Orogeny and may represent a vestige of missing marginal basins of the western Iapetus developed at the onset of subduction. The likely counterpart to Svalbard's blueschists is the ophiolitic sequence in the Pearya Terrane of northern Ellesmere Island. 相似文献
58.
Geographically weighted regression algorithm (GWR) has been applied to derive the spatial structure of urban heat island (UHI) in the city of Wroc?aw, SW Poland. Seven UHI cases, measured during various meteorological conditions and characteristic of different seasons, were selected for analysis. GWR results were compared with global regression models (MLR), using various statistical procedures including corrected Akaike Information Criterion, determination coefficient, analysis of variance, and Moran’s I index. It was found that GWR is better suited for spatial modeling of UHI than MLR models, as it takes into account non-stationarity of the spatial process. However, Monte Carlo and F3 tests for spatial stationarity of the independent variables suggest that for several spatial predictors a mixed GWR–MLR approach is recommended. Both local and global models were extended by the interpolation of regression residuals and used for spatial interpolation of the UHI structure. The interpolation results were evaluated with the cross-validation approach. It was found that the incorporation of the spatially interpolated residuals leads to significant improvement of the interpolation results for both GWR and MLR approaches. Because GWR is better justified in terms of statistical specification, the combined GWR?+?interpolated regression residuals (GWR residual kriging; GWRK) approach is recommended for spatial modeling of UHI, instead of widely applied MLR models. 相似文献
59.
Krzysztof Godziewski Cezary Migaszewski Maciej Konacki 《Monthly notices of the Royal Astronomical Society》2008,385(2):957-966
Precision radial velocity measurements of the Sun-like dwarf 14 Herculis published by Naef et al., Butler et al. and Wittenmyer, Endl & Cochran reveal a Jovian planet in a 1760-d orbit and a trend indicating the second distant object. On the grounds of dynamical considerations, we test a hypothesis that the trend can be explained by the presence of an additional giant planet. We derive dynamical limits to the orbital parameters of the putative outer Jovian companion in an orbit within ∼13 au. In this case, the mutual interactions between the Jovian planets are important for the long-term stability of the system. The best self-consistent and stable Newtonian fit to an edge-on configuration of Jovian planets has the outer planet in 9-au orbit with a moderate eccentricity of ∼0.2 and confined to a zone spanned by the low-order mean motion resonances 5:1 and 6:1. This solution lies in a shallow minimum of (χ2 ν )1/2 and persists over a wide range of the system inclination. Other stable configurations within 1σ confidence interval of the best fit are possible for the semimajor axis of the outer planet in the range of (6,13) au and the eccentricity in the range of (0, 0.3). The orbital inclination cannot yet be determined but when it decreases, both planetary masses approach ∼10 m J and for i ∼ 30° the hierarchy of the masses is reversed. 相似文献
60.
Educational tsunami evacuation map brochures in Washington and Oregon have been developed locally, resulting in significant
differences between the types of tsunami hazard information they include. This paper identifies six tsunami hazard information
types present in 38 brochures in Washington and Oregon: (1) tsunami hazard zone, (2) road network, (3) assembly areas, (4)
evacuation guidance, (5) infrastructure, and (6) terrain. It compares and contrasts these information types in the maps and
text of six of the brochures, including a proposed design standard in Oregon. Design differences of all 38 brochure maps are
then organized using principles of cartographic abstraction, which describe mapmaker decisions about selection, generalization,
and symbolization of information. We further use this framework to situate the information content of a new interactive Google
Maps tool in Oregon. Our assessment identifies limitations of current tsunami hazard information that may be relevant to improving
tsunami education. In theory, more advanced evacuation map tools can play an important role in reducing the limitations of
tsunami hazard information relevant to the public. The new Google Maps tool addresses few of these limitations. Recognizing
how map-making decisions define the underlying information content of evacuation maps can facilitate much needed future evaluations
and developments in evacuation map design. 相似文献