全文获取类型
收费全文 | 268篇 |
免费 | 2篇 |
专业分类
测绘学 | 5篇 |
大气科学 | 6篇 |
地球物理 | 90篇 |
地质学 | 84篇 |
海洋学 | 13篇 |
天文学 | 59篇 |
综合类 | 2篇 |
自然地理 | 11篇 |
出版年
2022年 | 1篇 |
2021年 | 1篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 6篇 |
2017年 | 12篇 |
2016年 | 13篇 |
2015年 | 7篇 |
2014年 | 10篇 |
2013年 | 17篇 |
2012年 | 6篇 |
2011年 | 25篇 |
2010年 | 10篇 |
2009年 | 18篇 |
2008年 | 14篇 |
2007年 | 15篇 |
2006年 | 10篇 |
2005年 | 9篇 |
2004年 | 10篇 |
2003年 | 6篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 5篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 10篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1991年 | 4篇 |
1990年 | 5篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 4篇 |
1984年 | 6篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1977年 | 4篇 |
排序方式: 共有270条查询结果,搜索用时 531 毫秒
251.
Andrzej Grniak Piotr Zieliski Elbieta Jekatierynczuk‐Rudczyk Magdalena Grabowska Tomasz Suchowolec 《洁净——土壤、空气、水》2002,30(4):179-189
Long‐term studies were conducted on the polymictic Siemianówka reservoir (SR), situated in a seminatural forest‐peat catchment in NE Poland. The studies were started on the second year of the reservoir's existence. The records showed dissolved organic carbon (DOC) concentrations gradually increasing up to 25…30 mg/L. The largest DOC pool in the reservoir comes from the spring load input, supplemented by the excessive development of phytoplankton with cyanobacteria dominance. The DOC limited the range of the photic zone, eliminated the occurrence of aquatic plants, and was a significant carrier of nutrients, which were gradually released to water, bringing about the “humoeutrophication” of the reservoir. 相似文献
252.
253.
Andrzej Hanyga 《Pure and Applied Geophysics》2014,171(9):2097-2109
Dispersion, attenuation and wavefronts in a class of linear viscoelastic media proposed by Strick and Mainardi (Geophys J R Astr Soc 69:415–429, 1982) and a related class of models due to Lomnitz, Jeffreys and Strick are studied by a new method due to the author. Unlike the previously studied explicit models of relaxation modulus or creep compliance, these two classes support propagation of discontinuities. Due to an extension made by Strick, either of these two classes of models comprise both viscoelastic solids and fluids. We also discuss the Andrade viscoelastic media. The Andrade media do not support discontinuity waves and exhibit the pedestal effect. 相似文献
254.
The paper concerns investigation of the credibility of tectonic interpretation of GNSS strain rates. The analysis was focused on stable regions, where the crustal deformations are small and the reliability of GNSS velocities is questionable. We are showing how the unreliable motion of stations affects calculated strains around them. We expressed distribution of local principal strains by a sinusoidal function and used them to investigate the significance of strain distortion. Then we used this method to investigate real motions of GNSS stations. As a test object we used Polish GNSS stations belonging to the ASG-EUPOS network. Station velocities were estimated on the basis of the 4.5 years of observations. The results let us identify stations that disturb the obtained local GNSS strain rate field. After verification and exclusion of some stations, the new GNSS strains show a much greater internal compatibility and also better fit to the directions of lithosphere stresses. 相似文献
255.
256.
Airborne Fungal Spores of Subalpine Zone of the Karkonosze and Izerskie Mountains (Poland) 总被引:4,自引:1,他引:3
The incidence of the airborne fungal spores was determined in the air of subalpine zone of the Karkonosze Mountains and of the Izerskie Mountains in the borderland between Poland and the Czech Republic. The experiment was conducted in 2011 and 2012 at three to four week intervals from May to October. Air samples were taken from three locations in the Karkonosze Mts. and one from the Izerskie Mts. To examine the air, the Air Ideal 3P sampler and acidified PDA medium were used. The results show that Cladosporium cladosporioides was the most abundant spore type in all the sampling locations (up to 30%), followed by Alternaria alternata (16%-20%), Fusarium (up to 10%) and Sclerotinia sclerotiorium (up to 6%). The lower spore counts were recorded in May samples, compared to the other months. In this case the snow cover, that was still present in the area at the beginning of May, may be the reason for the lower, compared to June, July and August samplings, CFU (Colony Forming Unit) counts in that month.. The influx of air masses from SE, S and SW sectors in the area under study may affect dissemination of the plant-pathogenic fungi from the Czech Republic and from the South of Europe in general. 相似文献
257.
258.
259.
Andrzej Aniszewski 《Acta Geophysica》2009,57(2):435-453
The paper addresses the 2D mathematical equation of conservative contaminant transport in an aquifer for chosen contaminants.
The contaminants (chlorides and sulfates) are subject to instantaneous reversible part of sorption process. The term of instantaneous
reversible sorption in the presented equation has been described by the non-linear Freundlich adsorption isotherm, widely
applied in practice in relation to static processes (for local equilibrium). The numerical solution (using the finite difference
method) has been based on the previously calculated values of longitudinal and transverse dispersion coefficients and the
non-linear adsorption parameters for the chosen contaminants. Based on this model, the values of chloride and sulfate concentration
isolines have been calculated and compared with the measured maximal concentrations in the chosen natural aquifer (installed
piezometers). Additionally, the values of chloride concentrations have been calculated taking into account the influence of
radioactive decay term, using the numerical value of the firstorder decay rate constant for an adopted theoretical radionuclide. 相似文献
260.
Bonnie A. Stevens Andrzej J. Maciejewski 《Celestial Mechanics and Dynamical Astronomy》2002,82(2):111-112