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191.
192.
In this study, future changes in regional extreme wave heights around the Korean Peninsula are projected by using the results of an atmosphere general circulation model and a third-generation wave model. The direct use of the model output at each grid point is not appropriate even though high resolution of 20 km is used for the models. Therefore, the model output is grouped into six regions around the Korean Peninsula. The grouping approach is reasonable in assessing climate change effects with alleviated model uncertainty. The extreme wave heights are simulated for two climate periods of 1979–2003 (present climate) and 2075–2099 (future climate). The model results are validated by comparing the simulated wave heights for the present climate with observed and hindcasted wave data. The extreme wave heights for the future climate are then projected for different seasons and in different regions. The 50-year return wave height in summer is projected to increase in most regions, especially in the high-latitude Yellow Sea and the East Sea, while the wave height in winter is projected to decrease in all the regions, especially in the East Sea. 相似文献
193.
Summary The study on the characteristics of aerosol in Seoul during springtime from 1998 to 2003 is performed by the size-resolved number concentrations of aerosol. Asian dust events occur in spring most frequently, but it has been often observed in wintertime since 1999. Since 2000, the number of Asian dust days has been increasing, and the intensity has been more severe until 2002. However, there were only 3 dust days in Seoul during the spring of 2003, since the synoptic cyclone was relatively not intense enough to rise and transport dust to Korean peninsula, and the air stream was usually tiled to north of Korean peninsula. In addition, the precipitation was relatively plentiful and the air temperature was cold enough not to keep dry soil condition.Haze is the suspended particles in the air, reducing visibility by scattering light, and it is often a mixture of aerosols and photochemical smog. Dry particles with diameters of the order of 0.1µm, are small enough to scatter short wavelengths of light. Haze occurs well in winter and spring, and severe haze is observed in the afternoon. The occurrence frequency of haze has been decreasing since 2000 except in May of 2003.During Asian dust events from 1998 to 2003, the number concentration of aerosol with diameters from 0.3µm to 0.5µm decreases notably, but that larger than 1µm increases rapidly. On the other hand, for the haze events the number concentration from 0.3µm to 0.5µm increases notably, but that larger than 1µm decreases. 相似文献
194.
This paper reviews the prospects for adaptation in world agriculture in the face of climate change. The record of experience
from previous decades demonstrates a considerable capacity to adapt and there is general optimism that successful adaptation
will be maintained. There are some grounds for concern because of the uncertainty surrounding global climate projections and
the probability of considerable regional variation in impacts. While world production may not be adversely affected, the prospects
are not so encouraging for low latitude agricultural regions, in part because of lower capacity to adapt. Attention has focused
on the farming community itself as the place where adaptation takes place, but now the processes of globalization are placing
adaptation more in the hands of agri-business, national policy makers, and the international political economy. The continued
success of adaptation rests more heavily on actions at the national level in the context of changing technology and world
trade liberalization. An adaptation policy framework is suggested as a vehicle to help understand and facilitate adaptation
in this changing context. 相似文献
195.
The Singapore seimic network and the seismicity of Singapore are briefly described,the four tremor events experienced by Singapore are discussed and the ground responses of different stations are compared,The tremor incident standing operation procedure is also prsented. 相似文献
196.
The finite strip method is used to study the dynamic response of surface strip foundations. This method is simple to use and versatile. The two-dimensional problem is effectively reduced to an equivalent one-dimensional problem. The choice of trigonometric series for the displacement functions results in the uncoupling of the terms of the series and a significant reduction in the semi-bandwidth of the complex set of equations, making the method well suited to small computers. Non-homogeneous soil profiles are treated as a matter of course. The finite strip solutions are shown to be in general agreement with other theoretical methods of analysis. 相似文献
197.
The waters of Naples Bay, Florida, and associated waterways were monitored for potentially pathogenic bacteria, specificallyVibrio cholerae, V. parahaemolyticus, Salmonella, andPseudomonas aeruginosa. Ten to twelve stations were sampled over a period of eleven months.Vibrio cholerae was recovered in 33.6% of the 116 total samples andSalmonella in 28.4% of the samples. The results show that these bacteria exist in these waters and can be recovered from areas with both high and low numbers of total and fecal coliforms. 相似文献
198.
199.
Jin-Hyeob Kwak Woo-Jung Choi Sang-Sun Lim Seung-Heon Lee Sang-Mo Lee Scott X. Chang Jae-Woon Jung Kwang-Sik Yoon Soo-Myung Choi 《Environmental Geology》2008,53(6):1331-1338
Electrical conductivity of saturated soil extracts (ECe) in three reclaimed tideland (RTL) soils on the west coast of Korea decreased with time since reclamation, indicating natural
desalinization through leaching of salts by precipitation water. Soil N concentration increased with decreasing ECe. With the increase in soil N concentration, the δ15N decreased, likely caused by the input of 15N-depleted N sources. As N2-fixing plant species were found in the oldest RTL, atmospheric N2 fixation likely contributed to the increase in soil N concentration in the oldest RTL. Negative δ15N (−7.1 to −2.0‰) of total inorganic N (NH4
++NO3
−) and published data on N deposition near the study area indicate that atmospheric N deposition might be another source of
N in the RTLs. Meanwhile, the consistently negative δ15N of soil NO3
− excluded N input from chemical fertilizer through groundwater flow as a potential N source, since NO3
− in groundwater generally have a positive δ15N. The patterns of δ15N of NH4
+ (+2.3 to +5.1‰) and NO3
− (−9.2 to −5.0‰) suggested that nitrification was an active process that caused 15N enrichment in NH4
+ but denitrification was probably minimal which would otherwise have caused 15N enrichment in NO3
−. A quantitative approach on N budget would provide a better understanding of soil N dynamics in the studied RTLs. 相似文献
200.