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71.
Vasil’ev D. Yu. Vodopyanov V. V. Zayzeva G. S. Zakirzyanov Sh. I. Semenov V. A. Sivokhip Zh. T. Chibilev A. A. 《Doklady Earth Sciences》2019,486(2):724-727
Doklady Earth Sciences - The results of long-term forecasting of the spring runoff in the Belaya River basin based on the water-balance model are presented. The structure and parameters of the... 相似文献
72.
随着湖库外源性污染的有效控制,沉积物污染特征成为影响湖库水环境质量的关键因素。本文以富硫型水库——汤河水库为研究对象,分析探讨水库沉积物的理化性质、重金属总量、酸可挥发性硫化物(acid volatile sulfide,AVS)和同步提取重金属(simultaneously extracted metals,SEM)的空间分布特征,采用沉积物基准法(sediment quality guidelines, SQGs)和AVS与SEM关系法对重金属可能诱发的生态风险和毒性效应进行评估。结果表明:汤河水库沉积物中AVS含量在0.03~51.75 μmol/g之间,并呈现坝前深水区>东支流库区>西支流库区的空间分布特征。根据Pearson相关性分析可知,汤河水库沉积物AVS含量与间隙水中SO42-浓度、沉积物烧失量(LOI)含量呈显著正相关,与沉积物间隙水中NO3-浓度和沉积物pH呈现显著负相关。间隙水中SO42-浓度和沉积物LOI含量是控制AVS产量的重要因素。水库沉积物中ΣSEM变化范围为0.52~2.75 μmol/g,呈现出东支流库区>坝前深水区>西支流库区的分布规律。水库沉积物中ΣSEM/AVS和ΣSEM-AVS的变化范围分别为0.06~22.73和-49.18~2.44 μmol/g,显示出水库坝前深水区表层0~10 cm沉积物不具有生态风险,而东、西支流库区沉积物中的SEM因为不能完全被AVS所固定而存在潜在生态风险。就单一重金属而言,汤河水库坝前深水区和东西支流中部区域沉积物Ni、Cu、Pb和Zn含量均介于临界效应含量(threshold effects level, TEL)值和可能效应含量(probable effect level, PEL)值之间,可产生低级风险毒性效应,但Ni的毒性效应风险接近中级,今后应予以重点关注。富硫型水库沉积物中容易出现高含量AVS,沉积物间隙水中SO42-和NO3-的浓度是决定沉积物AVS净产量的重要因素。流域内重金属土壤背景值以及工业、采矿产业排放的废水类型直接影响着诱发生态风险的重金属种类。 相似文献
73.
Rumyantsev V. A. Pozdnyakov Sh. R. Ulichev V. I. Chichkova E. F. Ryzhikov D. M. 《Izvestiya Atmospheric and Oceanic Physics》2017,53(9):1042-1049
Izvestiya, Atmospheric and Oceanic Physics - This article presents the results of a study of the dynamics of the shorelines of Lake Ilmen and the Tsimlyansk Reservoir to indicate the location of... 相似文献
74.
P. N. Makkaveev A. A. Polukhin A. V. Kostyleva E. A. Protsenko S. V. Stepanova Sh. Kh. Yakubov 《Oceanology》2017,57(1):48-57
During cruise 65 of the R/V Akademik Mstislav Keldysh in the Kara Sea, three transects were executed: one eastwards from the Novaya Zemlya Archipelago and two in the St. Anna and Voronin troughs. It was noted that the continental runoff affected the entire surveyed aquatic area, even at the northern extremity of the Novaya Zemlya Archipelago. The transect along the St. Anna Trough showed the presence of a slope frontal zone overlaid at the surface by a desalinated layer. The Voronin Trough was characterized by sliding of slope waters. The hydrochemical parameters show that the surveys were carried out during a recession of biological activity of the waters and that the peak bloom was over by that time. The hydrochemical structure of waters conformed to early autumn conditions, but before the beginning of intense cooling of surface waters. 相似文献
75.
Application of the SP algorithm to the INTERMAGNET magnetograms of the disturbed geomagnetic field 总被引:1,自引:0,他引:1
R. V. Sidorov A. A. Soloviev Sh. R. Bogoutdinov 《Izvestiya Physics of the Solid Earth》2012,48(5):410-414
The algorithmic system developed in the Laboratory of Geoinformatics at the Geophysical Center, Russian Academy of Sciences, which is intended for recognizing spikes on the magnetograms from the global network INTERMAGNET provides the possibility to carry out retrospective analysis of the magnetograms from the World Data Centers. Application of this system to the analysis of the magnetograms allows automating the job of the experts-interpreters on identifying the artificial spikes in the INTERMAGNET data. The present paper is focused on the SP algorithm (abbreviated from SPIKE) which recognizes artificial spikes on the records of the geomagnetic field. Initially, this algorithm was trained on the magnetograms of 2007 and 2008, which recorded the quiet geomagnetic field. The results of training and testing showed that the algorithm is quite efficient. Applying this method to the problem of recognizing spikes on the data for periods of enhanced geomagnetic activity is a separate task. In this short communication, we present the results of applying the SP algorithm trained on the data of 2007 to the INTERMAGNET magnetograms for 2003 and 2005 sampled every minute. This analysis shows that the SP algorithm does not exhibit a worse performance if applied to the records of a disturbed geomagnetic field. 相似文献
76.
S. B. Lobach-Zhuchenko V. V. Balaganskii M. Yu. Koreshkova K. I. Lokhov Sh. K. Baltybaev L. M. Stepanyuk Yu. S. Egorova S. A. Sergeev I. N. Kapitonov O. L. Galankina E. S. Bogomolov N. G. Berezhnaya V. V. Sukach 《Doklady Earth Sciences》2017,474(2):700-705
This report presents data on the geological structure and location of the orthopyroxenite inclusion in gneissic enderbites of the Bug granulite–gneiss domain. Three stages of orthopyroxenite formation were identified on the basis of studies of the mineral composition along with the U–Pb and Lu–Hf isotope systems of zircons. 相似文献
77.
Conflict of interests between water users in the Central Asian region and possible ways to its elimination 总被引:1,自引:0,他引:1
The current situation with water use in Central Asia is analyzed. It is shown that the optimal way to resolve the conflict
between irrigation and water power engineering in the region is their joint development by constructing large hydropower stations
with reservoirs. 相似文献
78.
Sh. R. Bogoutdinov A. D. Gvishiani S. M. Agayan A. A. Solovyev E. Kin 《Izvestiya Physics of the Solid Earth》2010,46(11):1004-1016
The International Real-time Magnetic Observatory Network (INTERMAGNET) is the world’s biggest international network of ground-based
observatories, providing geomagnetic data almost in real time (within 72 hours of collection) [Kerridge, 2001]. The observation
data are rapidly transferred by the observatories participating in the program to regional Geomagnetic Information Nodes (GINs),
which carry out a global exchange of data and process the results. The observations of the main (core) magnetic field of the
Earth and its study are one of the key problems of geophysics. The INTERMAGNET system is the basis of monitoring the state
of the Earth’s magnetic field; therefore, the information provided by the system is required to be very reliable. Despite
the rigid high-quality standard of the recording devices, they are subject to external effects that affect the quality of
the records. Therefore, an objective and formalized recognition with the subsequent remedy of the anomalies (artifacts) that
occur on the records is an important task. Expanding on the ideas of Agayan [Agayan et al., 2005] and Gvishiani [Gvishiani
et al., 2008a; 2008b], this paper suggests a new algorithm of automatic recognition of anomalies with specified morphology,
capable of identifying both physically- and anthropogenically-derived spikes on the magnetograms. The algorithm is constructed
using fuzzy logic and, as such, is highly adaptive and universal. The developed algorithmic system formalizes the work of
the expert-interpreter in terms of artificial intelligence. This ensures identical processing of large data arrays, almost
unattainable manually. Besides the algorithm, the paper also reports on the application of the developed algorithmic system
for identifying spikes at the INTERMAGNET observatories. The main achievement of the work is the creation of an algorithm
permitting the almost unmanned extraction of spike-free (definitive) magnetograms from preliminary records. This automated
system is developed for the first time with the application of fuzzy logic system for geomagnetic measurements. It is important
to note that the recognition of time disturbances is formalized and identical. The algorithm presented here appreciably increases
the reliability of spike-free INTERMAGNET magnetograms, thus increasing the objectivity of our knowledge of the Earth’s magnetic
field. At the same time, the created system can accomplish identical, formalized, and retrospective analysis of large archives
of digital and digitized magnetograms, accumulated in the system of Worldwide Data Centers. The relevant project has already
been initiated as a collaborative initiative of the Worldwide Data Center at Geophysical Center (Russian Academy of Sciences)
and the NOAA National Geophysical Data Center (Unite States). Thus, by improving and adding objectivity to both new and historical
initial data, the developed algorithmic system may contribute appreciably to improving our understanding of the Earth’s magnetic
field. 相似文献
79.
山东省泰安市大汶口盆地岩盐矿地质特征及开发意义 总被引:1,自引:0,他引:1
大汶口盆地岩盐矿均为第四系所覆盖,钻孔揭露,除第四系外,主要为古近系官庄群大汶口组。大汶口盆地主要是由南留断裂所控制。岩盐矿是大汶口盆地盐类矿床的主体,矿层多而集中,厚度大而变化小,品位高而稳定。矿层延展面积约45km3,其平面形态为一个椭圆形,在空间上整个含盐段似一个向北缓倾的大透镜体。矿石自然类型有3种,即块状岩盐(灰白盐)、含杂质岩盐(杂色盐)和脉状岩盐,其中以块状岩盐为主,含杂质岩盐次之,脉状岩盐不具有工业意义。该矿床地质条件好、埋藏深度适宜,外部建设条件好,该矿床具备大规模开发的条件,矿业开发可促进当地的经济发展.当地政府有关部门已在着手工作,推动该岩盐矿规模开发进程。 相似文献
80.