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471.
Xibai Zeng Shiming Su Xiliang Jiang Lianfang Li Lingyu Bai Yanrong Zhang 《洁净——土壤、空气、水》2010,38(3):238-241
In order to control and remediate arsenic (As) contaminated soil, sediment or water, fungi are used to investigate their potential accumulation and volatilization of As. In this study, after cultivation for 2 days, the dry weights of mycelia for Trichoderma asperellum, Fusarium oxysporum and Penicillium janthinellum all show an increased trend when the As(V) concentration ranges from 0–50, 0–50, 0–80 mg/L, respectively. When the culture system is loaded with 2500 μg As(V), which represents 50 mg/L As, and cultivated for 5 days, P. janthinellum presents the highest efficiency of 87.0 μg/g for As bioaccumulation, and the order of the efficiency for As bioaccumulation is P. janthinellum > T. asperellum > F. oxysporum. However, the order of the amount of volatilized As is F. oxysporum > P. janthinellum > T. asperellum, and the highest amount of volatilized As is observed for F. oxysporum at 181.0 μg. Thus, the ability of As bioaccumulation and biovolatilization for T. asperellum and P. janthinellum is reported for the first time in this study. 相似文献
472.
新疆地区县(市)地震应急能力指标体系的建立与区域差异初探 总被引:2,自引:2,他引:0
从新疆地区地震活动性、灾害背景及区域协同联动应急模式出发,在遵循科学性、系统优化和可操作性及区域特性等原则的基础上,采用层次分析法建立了县级行政单元的地震应急能力评价指标体系;继而建立了基于基础设施条件、基础人力物力财力、(县级)专项能力和专项经验及基础环境背景4个一类指标集的县(市)绝对地震应急能力综合评价模型,并根据新疆地区4类人员问卷调查资料,计算和分析了样本支持条件下各指标的权重及结果,将其应用在新疆地区县(市)地震应急能力等级划分中。结果表明,地震应急能力的空间分布格局的产生与区域经济发展水平和地理位置等方面所具备的优势是相适应的,安居富民工程对提升区域地震应急能力发挥了重要作用,少数民族聚集区应急能力有待加强,寒旱、高海拔地区等特殊地理因素影响不可忽视。 相似文献
473.
474.
Zoran Sušić Marinko Toljić Vladimir Bulatović Toša Ninkov Uroš Stojadinović 《Acta Geophysica》2016,64(5):1626-1654
In tectonically complex environments, such as the Pannonian Basin surrounded by the Alps–Dinarides and Carpathians orogens, monitoring of recent deformations represents very challenging matter. Efficient quantification of active continental deformations demands the use of a multidisciplinary approach, including neotectonic, seismotectonic and geodetic methods. The present-day tectonic mobility in the Pannonian Basin is predominantly controlled by the northward movement of the Adria micro-plate, which has produced compressional stresses that were party accommodated by the Alps-Dinarides thrust belt and partly transferred towards its hinterland. Influence of thus induced stresses on the recent strain field, deformations and tectonic mobility in the southern segment of the Pannonian Basin has been investigated using GPS measurements of the horizontal mobility in the Vojvodina area (northern Serbia). 相似文献
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476.
High-angle normal faulting in eastern China was an important tectonic process responsible for the rifting of the eastern Asian continental margin. Along the southern segment of the Tan-Lu fault system, part of the eastern China rift-system, 55–70° east-dipping normal faults are the oldest structures within this rift-system. Chlorite, pseudotachylite, and fault breccia are found in fault zones, which are characterized by microstructures and syn-deformation chlorite minerals aligned parallel to a down-dip stretching lineation. 40Ar/39Ar dating of syn-deformation chlorite and K-feldspar from the fault gouge zone yields cooling ages of ~75–70 Ma, interpreted as the timing of slip along the normal faults. This age is older than that of opening of the Japanese sea and back-arc extension in the west Pacific, but similar to the onset of the Indo-Asian (soft?) collision. 相似文献
477.
478.
479.
AbstractA new methodology is proposed for the calibration of distributed hydrological models at the basin scale by constraining an internal model variable using satellite data of land surface temperature (LST). The model algorithm solves the system of energy and mass balances in terms of a representative equilibrium temperature that governs the fluxes of energy and mass over the basin domain. This equilibrium surface temperature, which is a critical model state variable, is compared to operational satellite LST, while calibrating soil hydraulic parameters and vegetation variables differently in each pixel, minimizing the errors. This procedure is compared to the traditional calibration using only discharge measurements. The distributed energy water balance model, Flash-flood Event-based Spatially-distributed rainfall–runoff Transformation – Energy Water Balance model (FEST-EWB), is used to test this approach. This methodology is applied to the Upper Yangtze River basin (China) using MODIS LST retrieved from satellite data in the framework of the NRSCC-ESA DRAGON-2 Programme. The calibration procedure based on LST seems to outperform the calibration based on discharge, with lower relative error and higher Nash-Sutcliffe efficiency index on cumulated volume.
Editor D. Koutsoyiannis; Associate editor C. Perrin 相似文献
480.
Pan-African and early Paleozoic tectonothermal events in the Nyainrong microcontinent: Constraints from geochronology and geochemistry 总被引:4,自引:0,他引:4
To better understand the Pan-African-early Paleozoic tectonothermal events of the Nyainrong microcontinent and the constraints on its tectonic evolution, here we report the results of zircon LA-ICP-MS U-Pb dating and geochemical features of Amdo gneiss in the Nyainrong microcontinent. The outcrops of Amdo gneiss is about 30 km south of Amdo County in northern Tibet. The field occurrence, mineral composition, textural characteristics, and whole-rock geochemical features of the four gneiss samples indicate the protolith of the gneisses is intermediate-acid intrusive rock. Gneiss zircon trace element tracing and genetic analysis shows that zircon has typical characteristics of magmatic zircon. The 206Pb/238U concordant age of zircon is 505–517 Ma, corresponding to the Middle-Late Cambrian, which is the formation age of the protolith. The samples have characteristics of high silicon, alkali-rich, alkalic rate AR =1.73–3.7, the differentiation index DI = 70.78–90.28; rock aluminum saturation index ranges from 1.02 to 1.05, FeO / MgO ranges from 2.63 to 4.50, 10000 × Ga/Al ranges from 2.12 to 2.41, and P2O5 and Al2O3 content decreased with SiO2 increasing. Th and Y contents have a good positive correlation with Rb content; the genetic type of protolith of the gneiss is the differentiation of subalkaline over aluminum I-type granite. Combined with regional data, the tectonic setting of the Amdo gneiss protolith is closely related to the collision orogenic process. The preliminary view is that the Middle-Late Cambrian magmatic events developed on the microcontinent could be the result of Andean-type orogeny along the Gondwana super-continental margin after the end of the Pan-African orogeny. 相似文献