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961.
溪谷输变电站工程场地具有较复杂的双层地质结构.岩土体拉分变形明显.场地后缘及底部岩土体的主应力和剪应力集中明显,堆积体内部岩体处于拉分松弛状态.岩土体的潜在变形模式以蠕滑-拉裂为主.在水库蓄水与地震共同作用的极限工况下.场地处于潜在不稳定状态. 相似文献
962.
963.
964.
The Yitong(伊通) basin is a Late Mesozoic and Cenozoic continental sedimentary basin in Northeast China.On the basis of well tests and seismic data,we use the 2D modeling technique to rebuild the pressure evolution and hydrocarbon migration in the Moliqing(莫里青) fault depression of the Yitong basin.Based on the modeling results,four conclusions are drawn as follows.(1) The Eocene Shuangyang(双阳) Formation within the Moliqing fault depression had entirely undergone three epi-sodic cycles of pressure accumulation... 相似文献
965.
Source Apportionment of PAHs Using Two Mathematical Models for Mangrove Sediments in Shantou Coastal Zone,China 总被引:2,自引:0,他引:2
Thirty-five surface sediment samples collected from three mangroves in Shantou coastal zone, China in 2007 were analyzed for
a suite of polycyclic aromatic hydrocarbons (PAHs). Two mathematical models were used to determine the profiles and relative
contributions of PAH sources to the mangroves. The two models are principal component analyses (PCA) with multiple linear
regression analysis (MLR) and positive matrix factorization (PMF). Both models identified five factors and gave excellent
correlation coefficients between predicted and measured levels of 16 PAH compounds, but the results had some differences.
The PAH contribution rate attributed to vehicular emission sources identified by PCA-MLR was 37.20%, but the rate identified
by PMF was only 12.37%. The main sources identified by PCA-MLR were combination of biomass/coal combustion and vehicular emissions,
whereas the main source identified by PMF was only biomass/coal combustion. The PMF analysis was the preferred model for the
paper data set. 相似文献
966.
967.
Sorption and desorption behavior of lead on a Chinese kaolin 总被引:1,自引:0,他引:1
Shengli Wang Zhongren Nan Xinde Cao Qin Liao Jiao Liu Wenfei Wu Ting Zhou Cuicui Zhao Wangqiang Jin 《Environmental Earth Sciences》2011,63(1):145-149
The sorption and desorption of Pb on kaolin from Suzhou, China were investigated. The sorption experiment was conducted in
a 0.01 M NaNO3 aqueous solution with respect to the effects of initial Pb concentration, pH, solid/solution ratio, and temperature. Langmuir
and Freundlich models well described equilibrium isotherms of Pb sorption. Less than 5% of Pb sorbed was desorbed with 0.01 M
NaNO3 extraction, suggesting a dominant specific sorption of Pb. As the initial pH increased, the sorption of Pb on the kaolin
increased. More than 60% of Pb was sorbed at pH 2.69 far below the point of zero net charge of the kaolin at 4.2, indicating
a mechanism of Pb inner-sphere complex or by chemisorption. Lead sorption decreased with increasing temperature, indicating
a process of exothermic sorption. 相似文献
968.
Peiyan Sun Zhenhui Gao Lixin Cao Xinping Wang Qing Zhou Yuhui Zhao Guangmei Li 《中国海洋大学学报(英文版)》2011,10(1):35-41
In recent years, oil spill accidents occur frequently in the marine area of China. Finding out the spilled oil source is a
key step in the relevant investigation. In this paper, a step-by-step fingerprinting identification method was used in a spilled
oil accident in the Bohai Sea in 2002. Advanced chemical fingerprinting and data interpretation techniques were used to characterize
the chemical composition and determine the possible sources of two spilled oil samples. The original gas chromatography -flame
ionization detection (GC-FID) chromatogram of saturated hydrocarbons was compared. The gas chromatography-mass spectrometry
(GC/MS) chromatograms of aromatic hydrocarbons terpane and sterane, n-alkane and poly-aromatic hydrocarbons (PAHs) were analyzed. The correlation analysis on diagnostic ratios was performed with
Student’s t-test. It is found that the oil fingerprinting of the spilled oil (designated as sz1) from the polluted sand beach
was identical with the suspected oil (designated as ky1) from a nearby crude oil refinery factory. They both showed the fingerprinting
character of mixed oil. The oil fingerprinting of the spilled oil (designated as ms1) collected from the port was significantly
different from oil ky1 and oil sz1 and was with a lubricating oil fingerprint character. The identification result not only
gave support for the spilled oil investigation, but also served as an example for studying spilled oil accidents. 相似文献
969.
Morphology and life history of a brown alga Scytosiphon lomentaria (Lyngbye) Link (Scytosiphonaceae, Phaeophyceae) were investigated from 2005 to 2009 in the coastal waters of Dalian, China. The erect thalli collected in the field were tubular, hollow, and commonly constricted at intervals. Ascocysts were presented. Plurilocular gametangia, which were positioned in continuous sori on the erect thallus surface, produced biflagellar gametes. Gametophytes were dioecious and gametes were nearly isogamous. Gametes fusion occurred in three types. Type one, female and male gametes fused directly while swimming; type two, female gamete settled first, with which a male one contacted and fused rapidly; type three, while settling adjacently, a male gamete’s entire protoplast moved slowly into the previously settled female one, with only an empty cell membrane left. In culture zygotes developed into crustose sporophytes that formed unilocular sporangia. Biflagellar zoospores developed into erect thalli that formed plurilocular gametangia. The results indicated that a periodical heteromorphic alternation history with haploid gametophyte generation and diploid sporophyte generation exists in S. lomentaria of the Dalian populations. 相似文献
970.
Wei-Bin Wen Fang Wang Chun-Lai Li Jing Wang Li Cao Jian-Jun Liu Xu Tan Yuan Xiao Qiang Fu Yan Su Wei Zuo 《中国天文和天体物理学报》2014,(12)
The Moon-based Ultraviolet Telescope(MUVT) is one of the payloads on the Chang'e-3(CE-3) lunar lander. Because of the advantages of having no atmospheric disturbances and the slow rotation of the Moon, we can make long-term continuous observations of a series of important celestial objects in the near ultraviolet band(245~340 nm), and perform a sky survey of selected areas, which cannot be completed on Earth. We can find characteristic changes in celestial brightness with time by analyzing image data from the MUVT, and deduce the radiation mechanism and physical properties of these celestial objects after comparing with a physical model. In order to explain the scientific purposes of MUVT, this article analyzes the preprocessing of MUVT image data and makes a preliminary evaluation of data quality. The results demonstrate that the methods used for data collection and preprocessing are effective, and the Level 2A and 2B image data satisfy the requirements of follow-up scientific researches. 相似文献