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81.
Domenico Miriello Marco Malagodi Silvestro Antonio Ruffolo Mauro Francesco La Russa Gino Mirocle Crisci Antonino Pezzino Rita Galluccio Donatella Barca Elisa Marasco 《Environmental Earth Sciences》2010,60(4):829-836
The monumental tomb of Jefferson Page, an officer in the American Navy, was built in 1899 and is located in the Non-Catholic
Cemetery of Rome (Italy). This study presents complementary diagnostic studies characterizing the stone of the tomb and the
weathering and decay phenomena it has undergone. The monument is made of a single type of whitish marble, variously veined
and often covered with black patinas. Petrographic, isotopic and LA-ICP-MS analyses attribute the marble to the Carrara district.
SEM/EDS and microbiological analyses indicate that the black patinas are due to cyanobacterial autotrophic and fungin heterotrophic
colonization. Fourier-transform infrared spectroscopy revealed the presence of organic material on some portions of the tomb,
due to undocumented restoration carried out with a mixture of marble powder and a polyester resin. 相似文献
82.
Wolfango Plastino Romano Plenteda George Azzari Andreas Becker Paul R. J. Saey Gerhard Wotawa 《Pure and Applied Geophysics》2010,167(4-5):559-573
Understanding radioxenon time series and being able to distinguish anthropogenic from nuclear explosion signals are fundamental issues for the technical verification of the Comprehensive Nuclear-Test-Ban Treaty. Every radioxenon event categorisation methodology must take into account the background at each monitoring site to uncover anomalies that may be related to nuclear explosions. Feedback induced by local meteorological patterns on the equipment and on the sampling procedures has been included in the analysis to improve a possible event categorisation scheme. The occurrence probability of radioxenon outliers has been estimated with a time series approach characterising and avoiding the influence of local meteorological patterns. A power spectrum estimator for radioxenon and meteorological time series was selected; the randomness of the radioxenon residual time series has been tested for white noise by Kolmogorov–Smirnov and Ljung–Box tests. This methodological approach was applied to radioxenon data collected at two monitoring sites located at St. John’s, Canada and Charlottesville, USA, equipped with two different noble gas systems. It shows different feedback with local meteorological patterns and randomness for the radioxenon data recorded at the selected sites of St. John’s and Charlottesville as well as a different occurrence probability of the outliers in the normalized radioxenon original and residual time series. 相似文献
83.
Romano E Bergamin L Finoia MG Carboni MG Ausili A Gabellini M 《Marine pollution bulletin》2008,56(3):439-457
In the 20th century an important industrial plant operated on the coastal area of Bagnoli. After its closing, an integrated study of environmental characterisation aimed at restoration started. The survey conducted was based on chemical and sedimentological analyses integrated with benthic foraminifera analyses. Statistical analysis of the data shows sectors with a distinct type and degree of pollution. Particularly, pollution linked to the silty sediment fraction, mainly due to Pb and Zn, was recognised in front of the southern sector of the plant. The study of benthic foraminifera provides evidence for a pollution-tolerant character in some species like Haynesina germanica and Quinqueloculina parvula. In addition, two species among the 113 recognised show high percentages of abnormal specimens. These percentages show a statistical correlation with some pollutants (PAHs, Mn, Pb and Zn). In addition, Energy Dispersive Spectrometry shows small amounts of Fe ions included in deformed tests of Miliolinella subrotunda. Because the number of these deformations is positively correlated to the concentration of PAHs, Mn and Zn, the inability of some specimens to exclude the foreign elements from the crystalline reticulum of the test could be attributed to the potential toxic effect of these pollutants. 相似文献
84.
85.
I. Ermolli F. Giorgi P. Romano F. Zuccarello S. Criscuoli M. Stangalini 《Solar physics》2014,289(7):2525-2545
Several studies indicate that fractal and multifractal parameters inferred from solar photospheric magnetic field measurements may help assessing the eruptive potential of Active Regions (ARs) and also predicting their flare activity. We further investigate this topic, by exploring the sensitivity of some parameters already used in the literature on data and methods employed for their estimation. In particular, we measured the generalized fractal dimensions D 0 and D 8, and the multifractal parameters C div and D div, on the time series of photospheric magnetograms of the flaring AR NOAA 11158 obtained with the SOHO/MDI and SDO/HMI. The observations by the latter instrument are characterized by a higher spatial and temporal resolution, as well as higher flux sensitivity, than the ones obtained from SOHO/MDI, which were widely employed in earlier studies. We found that the average and peak values of complexity parameters measured on the two data sets agree within measurement uncertainties. The temporal evolution of the parameters measured on the two data sets show rather similar trends, but the ones derived from the SOHO/MDI observations show larger and spurious variations over time than those deduced from analysis of the corresponding SDO/HMI data. We also found a larger sensitivity of these measurements to characteristics of the data analyzed than reported by earlier studies. In particular, analysis of the higher resolution and higher cadence SDO/HMI data allows us also to detect slight variations of the complexity indicators that cannot be derived from the analysis of the SOHO/MDI data. These variations occur right after the major events in the analyzed AR. They may be the signature of photospheric effects of coronal magnetic field re-arrangement. 相似文献
86.
Massimo Zecchin † Francesco Massari Donatella Mellere‡ Giacomo Prosser§ 《Basin Research》2004,16(1):117-143
The complex development of the northern Crotone Basin, a forearc basin of the Calabrian Arc (Southern Italy), has been documented by sedimentological, stratigraphic and structural analyses. This Mediterranean‐type fault bounded basin consists of small depocentres commonly characterized by a mix of facies that grades from continental to shallow marine. The lower Pliocene infill of the Crotone Basin consists of offshore marls (Cavalieri Marl) that grade upwards into a shallow‐marine to continental succession up to 850 m thick (Zinga Formation). The succession is subdivided into three main stratal units: Zinga 1, Zinga 2, Zinga 3 bounded by major unconformities. The Zinga 1 stratal unit grades from the Cavalieri Marl to deltaic and shoreface deposits, the latter organized into several stacked progradational wedges that show spectacular thickness changes and progressive unconformities related to salt‐cored NE‐trending growth folds and listric normal faults. The Zinga 2 stratal unit records a progressive and moderate deepening of the area, marked by fluvial sedimentation at the base, followed by lagoonal deposits and by a stacking of mixed bioclastic and siliciclastic shoreface units, organized into metre‐scale high‐frequency cycles. Deposition was controlled by NE‐trending synsedimentary normal faults that dissected the basin into a series of half‐grabens. Hangingwall stratigraphic expansion was compensated by footwall condensed sedimentation. The extensional tectonic regime continued during sedimentation of the Zinga 3 stratal unit. Deposition confined within structural lows during a generalized transgressive phase led to local enhancement of tidal flows and development of sand‐wave trains. The tectonic setting testifies the generalized structural domain of a forearc region. The angular unconformity at the top of the Zinga 3 stratal unit is regional, and marks the activation of a large‐scale tectonic phase linked to strike‐slip movements. 相似文献
87.
G. Romano 《Astrophysics and Space Science》1976,44(2):405-408
This paper gives the results of a photometric study of star-like blue objects Nos. 14, 15, 16, 17, and 18 discovered by Börngenet al. (1970) in the field of M31 and of the QSO OA 33. Three of these objects-Nos. 14, 16 and 17-exhibit variable light. No. 14 is a probable U Geminorum-star; No. 16 is a QSO and very likely also the No. 17. Finally, we suggest a candidate for the optical counterpart of OA 33. 相似文献
88.
Dr. Romolo Romano 《International Journal of Earth Sciences》1968,57(3):773-783
The author presents 32 new analyses of volcanites from Pantelleria and draws some magmatological and geochemical conclusions.
Dedicated to Professor Dr. A.Rittmann on the occasion of his 75. birthday 相似文献
Zusammenfassung Der Autor gibt 32 neue Analysen von Vulkaniten von Pantelleria bekannt und zieht daraus einige magmatologische und geochemische Schlußfolgerungen.
Résumé L'auteur présente 32 analyses nouvelles de roches volcaniques de l'île de Pantelleria et en tire des conclusions d'ordre magmatologique et géochimique.
Riassunto Nella presente nota, l'Autore riporta 32 nuove analisi di vulcaniti di Pantelleria traendone delle conclusioni di carattere magmatologico e geochimico.
32 Pantelleria. , .
Dedicated to Professor Dr. A.Rittmann on the occasion of his 75. birthday 相似文献
89.
The speciation of water dissolved in glasses along the join NaAlSi3O8-KAlSi3O8 has been investigated using infrared spectroscopy. Hydrous melts have been hydrothermally synthesized by chemical equilibration
of cylinders of bubble-free anhydrous start glasses with water at 1040° C and 2 kbar. These melts have been isobarically and rapidly (200° C/s) “drop”-quenched to room temperature and then subsequently depressurized. The speciation of water in the quenched glasses
reflects the state of water speciation at a temperature (the so-called fictive temperature) where the quenched-in structure
of the glasses closely corresponds to the melt structure at equilibrium. This fictive temperature is detectable as the macroscopically
measureable glass transition temperature of these melt compositions. A separate set of experiments using vesicular samples
of the same chemistry has precisely defined the glass transition temperature of these melts (±5° C) on the basis of homogenization temperatures for water-filled fluid inclusions (Romano et al. 1994). The spectroscopic
data on the speciation of water in these quenched glasses has been quantified using experimentally determined absorptivities
for OH and H2O for each individual melt composition. The knowledge of glass transition temperatures, together with quantitative speciation
data permits an analysis of the temperature dependence of the water speciation over the 113° C range of fictive temperatures obtained for these water-saturated melts.
The variation of water speciation, cast as the equilibrium constant K where
K = [H2O] [O
m
]/[OH]2
is plotted versus the fictive temperature of the melt to obtain the temperature dependence of speciation. Such a plot describes
a single linear trend of the logarithm of the equilibrium constant versus reciprocal temperature, implying that the exchange
of K for Na has little influence on melt speciation of water. The enthalpy derived from temperature dependence is 36.5(±5) kJ/mol.
The results indicate a large variation in speciation with temperature and an insensitivity of the speciation to the K–Na exchange.
Received: 8 March 1995/Accepted: 6 June 1995 相似文献
90.