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31.
In this study, it was aimed to characterize temporal variations of air pollutants for determining contribution to pollution episodes and to obtain correlations between these pollutants. With this aim we used data analysis for measured sulfur dioxide (SO2), particulate matter (PM, black fume and PM10), nitrogen oxides (NOx), ozone (O3), carbon monoxide (CO), methane (CH4), and non‐methane hydrocarbons (NMHC) recorded in Kocaeli, one of the most industrilizated cities of Turkey. Pollutant concentrations were the results of continuous and semi‐automatic measurements. Semi‐automatic measurements of SO2 and PM (black fume) were enclosing period from 1987 to 2008 whereas continuous monitoring of all pollutants included years of 2007–2009. In the first stage of the study daily, monthly, annual, and seasonal variations of pollution were researched. Annual average concentrations were compared with limits set by Air Quality Protection Regulation (AQPR), Air Quality Evaluation and Management Regulation (AQEMR), World Health Organization (WHO), European Union (EU), and National Ambient Air Quality Standards (USEPA). In the following stage relationships between pollutants such as NO2–O3, NOx–CO, NOx–NMHC, and NOx–SO2 were investigated and correlation coefficients were determined as 0.87, 0.56, 0.51, and 0.69, respectively. R2 values of regression models developed from these correlations were 0.78, 0.56, 0.34, and 0.72, respectively. Vehicle density of the traffic was evaluated with NOx–O3 emissions and decrease was seen in NOx emissions due to decreasing vehicle density at weekends whereas O3 concentrations increased. These correlations enable prediction of the parameters that cannot be measured which is important for providing improvement in early warning systems. 相似文献
32.
Hyunsun Do Michael Brady Demetri P. Telionis Pavlos P. Vlachos Roe-Hoan Yoon 《International Journal of Mineral Processing》2011,98(1-2):66-73
Numerical and experimental results of drying and wetting foam are presented. Foam can be wetted by wash water delivered on its top boundary, or drained by allowing the liquid to move downward in response to gravity. These processes are governed by nonlinear equations that in special cases accept exact solutions. Here we develop a numerical model that satisfies realistic boundary conditions. Numerical results are presented in conjunction with experiments conducted with coarsening foam. In addition, calculations were carried out modeling the wetting and draining of coarsened foam. From the simulations and experiments, coarsening bubbles were found responsible for accelerating drainage, or vice versa. 相似文献
33.
R. J. Banu Ph.D. K. U. Do Ph.D. I. T. Yeom M.Sc. 《International Journal of Environmental Science and Technology》2008,5(1):93-98
The alkalinity plays an important role in phosphorus removal using coagulant. The dosage of coagulant in the low alkalinity wastewater is limited due to rapid pH changes. In the present study, a series of jar test was conducted using low alkalinity wastewater (50 mg/L) to evaluate the optimum pH, dosage and performance parameters (slow mixing and settling time) for the common coagulant alum. From the experiment, it was found that the dosage of coagulant and removal of phosphorus depend upon the pH of the wastewater after adding coagulant. The final optimum pH for efficient P removal was found to be within the range of 5.7–5.9. This range acts as an indicator and it is the maximum tolerable pH range for phosphorus removal for low alkalinity wastewater. The optimum time for slow mix and settling was found to be 20 min. The optimum mole ratio of alum to remove one mole of phosphorous was found to be 2.3. The alum coagulation at pH 7 produced effluent with the total residual phosphorus and reactive phosphorus content of 0.3 and 0.9 mg/L, respectively. 相似文献
34.
A. Gałuszka Z. Migaszewski A. Duczmal-Czernikiewicz S. Dołęgowska 《International Journal of Environmental Science and Technology》2016,13(11):2649-2662
Spatial distribution patterns of As, Ba, Cd, Cr, Cu, Mn, Ni, Pb, U and Zn were determined in topsoil samples collected after 40 years of chemical remediation conducted in the inoperative “Staszic” pyrite–uranium mine in the Holy Cross Mountains, south-central Poland. Soil samples were taken from 58 sites using a systematic random sampling design. Selected samples were subjected to an X-ray diffractometry analysis on bulk soils and separated clay fractions. Hematite, goethite and gypsum are common mineral phases in soil samples. Technogenic soils developed on reclaimed mine spoils show uniform spatial element distribution patterns and additionally a distinct enrichment in As, Pb, Mn, U and Zn. Mineral and chemical composition of soils vs. rocks points to the lithogenic source of the determined elements. The results of chemical analysis have been used for evaluation of geochemical background of trace elements in the study area with the iterative 2σ-technique. This investigation shows that using mean crustal element concentrations (Clarke values) as proxies of threshold values in soils are not useful for determination of strongly positive geochemical anomalies. A modified enrichment factor, i.e. a local enrichment factor, is proposed for identification of sites where soils are contaminated. 相似文献
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Doğan Bülent Aşci Metin Karakaş Ahmet Pekşen Ertan Erener Arzu Çepni Murat Selim Yavuzyilmaz Selin Alahmad Mohammad Sertçelik Fadime Sertçelik İbrahim Kurtuluş Cengiz 《Natural Hazards》2021,109(2):1675-1716
Natural Hazards - The Northern Branch of the North Anatolian Fault System controls and deforms the Izmit Basin and the Sapanca Lake Basin in the study area. Unlike the Sapanca Lake Basin, the... 相似文献
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The 17 August 1999
zmit earthquake significantly deformed the earth's crust in the Marmara Region, especially in the Gölcük–Sapanca Zone, Turkey. It broke a 150-km long segment of the northern branch of North Anatolian Fault Zone. The geodetically determined moment magnitude was Mw=7.5. Global Positioning System (GPS) sites, which are a small subset of the Marmara Continuous GPS Network (MAGNET), and survey sites in the region were studied to estimate coseismic and postseismic deformations, using different methodologies with linear, quadratic and exponential kinematic models. Six GPS epochs for these sites, which were carried out before and after the 17 August 1999
zmit earthquake, were used to define the kinematic models. The quadratic deformation model was also applied to determine the time-dependent crustal movement parameters (velocity and acceleration) of the sites, using the Kalman filter technique. In order to show the differences between the models, the estimated deformation fields on the last epoch were compared. In all models, as expected, the faults near the sites show large coseismic displacements with fault parallel direction, whereas the far sites show small coseismic displacements due to the effects of the
zmit earthquake. Each kinematic model, fitted to the epochs after the earthquake, shows different behaviour. While the linear model shows insufficient results, the nonlinear models (quadratic and exponential) give the best fitted to the postseismic deformations. As a result of Kalman filter analysis, the fault near-sites shows significant velocities with fault parallel direction, whereas the far sites have insignificant velocities. All stations have insignificant accelerations in the last epoch. 相似文献
40.
For the first time, ichthyoliths are described from the Santos sedimentary basin, offshore southern Brazil. Isolated teeth, dermal scales and the first documented otoliths from Cretaceous (Albian) to Recent cuttings from five wells are described. The following groups are represented: Chondrichthyans: Triakidae, Carcharhinidae; Ginglymostomatidae: ?Ginglymostoma sp., Lamnidae indet., Scyliorhinidae; Osteichthyans: Teleostei; Myctophiidae: Diaphus aff. splendidus sp. complex, Diaphus spp., Diaphus cf. garmani, Ceratoscopelus aff. warmingii; Sternoptychidae: Valenciennellus tripunctulatus, teeth of indeterminate Teleostei. The majority of these ichthyofossils represent extant forms, known to occur in the Atlantic Ocean, and are of potential value for stratigraphical correlations between oil‐yielding basins in the region. Ostracods are not well preserved but can be identified to generic level indicating marine environments. The ostracod faunas offer potential for intrabasinal correlation in the Eocene and Oligocene. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献