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941.
湖南高温日时空分布特征及高温日数气候预测 总被引:1,自引:0,他引:1
利用1961—2013年湖南74个气象观测站逐日高温观测资料,建立了较完整的湖南高温日时间序列,分析了湖南高温日时空分布及变化趋势。结果表明,湖南高温日呈增加趋势,每10年增加2天左右,湘北高温日增加趋势显著;高温最长持续日数总体上湘南大部呈弱的减少趋势,每10年减少0.5天左右,湘中及湘北则呈较强的增加趋势,每10年增加1天左右。20世纪90年代以来,湖南高温天气显著增多、增强。利用最优子集回归构建气候预测模型,预测湖南高温平均出现日数,预测效果较好,可在业务中应用。 相似文献
942.
943.
Cheng Ying Liu Hongyan Wang Hongya Chen Deliang Ciais Philippe Luo Yao Wu Xiuchen Yin Yi 《中国科学:地球科学(英文版)》2021,64(10):1774-1783
Although alpine ecosystems have been commonly recognized as sensitive to recent climate change, few studies have examined its impact on the long-term productivity of vegetation and soil erosion. Using paleoecological records, these two aspects were examined in the alpine zone of the Taibai Mountains(elevation, 3767 m) in monsoon-dominated East Asia since the middle Holocene. Proxies for the productivity of vegetation and severity of soil erosion from high-resolution alpine lacustrine records show that the productivity and soil erosion were closely related to mean annual temperature and summer precipitation from the East Asian Summer Monsoon(EASM), respectively. Specifically, when the mean annual temperature was low and precipitation was abundant, during 5800–4000 calendar years before the present(cal. yr BP), the alpine ecosystem was characterized by low vegetation productivity and severe soil erosion. However, the productivity increased and soil erosion decreased from 4000 cal. yr BP onwards. These results highlight the role of paleoecological evidence in studying ecosystem services on longer time scales, which is significant in making policies for sustainable development under climate change in regions for which such long-term monitoring data are not available. 相似文献
944.
利用气象和环保资料详细分析了武威市空气质量的特点,针对不同季节、不同时次分别建立了沙尘暴短时、短期预报模式及空气质量统计预报、潜势预报模式,经检验效果良好。应用Fortran和VB语言设计编程,建立了武威市空气质量预报系统,该系统包括沙尘暴预报预警服务系统、空气质量统计预报系统和空气质量潜势预报系统,直接和MICAPS系统接口,具有资料处理、动力统计预报、潜势预报等模式计算及资料采集、处理、模式运行、预报显示、产品分发、资料查询、预报评分等多种功能,在业务应用中效果良好。 相似文献
945.
地市级气象灾害短信预警系统 总被引:7,自引:6,他引:1
龙岩短时灾害性天气预警系统从提高气象预警信息的准确率及制作发布的时效和针对性出发,将灾害天气的多级自动预警、预警短信快捷制作和高效自动发布三者紧密结合起来,建立以即时手机气象预警短信息发布为主的灾害性天气预警、制作、发布一体化流程。将密切结合地方防灾减灾及经济建设需要的手机气象预警发布对象分级分类和地理信息化,应用电子地图与雷达产品、区域自动站等资料叠加,快捷制作气象预警短信和图形化自动选定手机发布对象,直接向防灾各部门和第一线用户发布,显著提高了短时灾害性天气监测预警能力和预警短信制作发布时效。图形可视化操作直观快捷、地域和级别预警针对性强,短信发布机动灵活、以点带面,具有很强的时效性和覆盖面。 相似文献
946.
气候变化科学的最新认知 总被引:239,自引:22,他引:217
政府间气候变化专门委员会(IPCC)第一工作组于2007年2月2日发布的第四次评估报告明确指出,近100 a(1906-2005年)地球表面平均温度上升了0.74℃,近50 a的线性增温速率为0.13℃/10 a,1850年以来最暖的12个年份中有11个出现在近期的1995-2006年。全球变暖已经是不争的科学事实,报告认为人类活动是近50 a全球气候系统变暖的主要原因。 IPCC评估报告是国际科学界对气候变化问题最权威、最全面的认识,代表了目前全球气候变化研究的科学认识水平,是国际上制定相关政策的重要依据。 相似文献
947.
自动气象站气压传感器调试方法 总被引:3,自引:3,他引:0
目前,国产自动气象站所用的气压传感器是芬兰Vaisala公司的Ptb220型气压传感器,该传感器具有精度高、稳定性好等特点,在各厂家生产的自动站中均有应用。但在检定过程中发现有个别传感器会出现超差或使用一段时间后产生漂移,用现有的检定手段无法消除误差。经与Vaisala公司技术人员多次沟通和大量实验,找出一套行之有效的调试方法,可以将气压传感器的误差用参数设置的方法设置到传感器内存中,将其控制在要求范围内,下面详述此方法,以供参考。 相似文献
948.
This study is based on both a generic and species level investigation of the individual size of the latest Permian conodont
Neogondolella Pa elements collected from Meishan Section A, Changxing, Zhejiang Province. In this study, an obvious size reduction of Neogondolella Pa elements within bed 24e of the upper Changxing Limestone is recognized. The size variation of the Neogondolella occurs simultaneously with some important events including the negative shift of δ
13C, change in the ratio of the abundance of cyanobacterial biomarkers versus that of other general bacterial biomarkers and
the shallowing of the sea water. Through the investigation of the paleoenvironmental changes and the analysis of the paleoecology
of the conodont genus Neogondolella, the authors propose that the major factors for the size reduction of species of the conodont genus Neogondolella are food shortages caused by the mass extinction, the shallowing of the sea water as well as the increase in opacity of the
sea water during the end Permian. The same phenomenon of Neogondolella size reduction is also observed in preliminary research from the same horizon at Shangsi Section, Sichuan Province. All the
evidence suggests that there was a mass extinction that occurred at the horizon of bed 24e, and the evidence supports the
viewpoint of a multi-phase mass extinction during the Permian and Triassic transition in South China. 相似文献
949.
Two possible mechanisms for vortex self-organization 总被引:3,自引:0,他引:3
Since the 21st century, the self-organization phe-nomenon has drawn a wide attention of Chinese sci-ence and technology researchers, and the study fields involve silicate chemistry[1, 2], the classification of re-mote sensing data[3], nanometer material[4―6], medium resistance to discharges[7], forest fires[8], mud-rock flow[9], sandpile formation[10, 11], urban geography[12], economic geography[13], intense storms over the Loess Plateau[14] and vortices over the Tibetan Plateau[15], etc. Re… 相似文献
950.
Clifford E. Singer T. S. Gopi Rethinaraj Samuel Addy David Durham Murat Isik Madhu Khanna Brandon Kuehl Jianding Luo Wilma Quimio Kothavari Rajendran Donna Ramirez Ji Qiang Jürgen Scheffran T. Nedjla Tiouririne Junli Zhang 《Climatic change》2008,88(3-4):309-342
Probability distributions for carbon burning, atmospheric CO2, and global average temperature are produced by time series calibration of models of utility optimization and carbon and heat balance using log-linear production functions. Population growth is used to calibrate a logistically evolving index of development that influences production efficiency. Energy production efficiency also includes a coefficient that decreases linearly with decreasing carbon intensity of energy production. This carbon intensity is a piecewise linear function of fossil carbon depletion. That function is calibrated against historical data and extrapolated by sampling a set of hypotheses about the impact on the carbon intensity of energy production of depleting fluid fossil fuel resources and increasing cumulative carbon emissions. Atmospheric carbon balance is determined by a first order differential equation with carbon use rates and cumulative carbon use as drivers. Atmospheric CO2 is a driver in a similar heat balance. Periodic corrections are included where required to make residuals between data and model results indistinguishable from independently and identically distributed normal distributions according to statistical tests on finite Fourier power spectrum amplitudes and nearest neighbor correlations. Asymptotic approach to a sustainable non-fossil energy production is followed for a global disaggregation into a tropical/developing and temperate/more-developed region. The increase in the uncertainty of global average temperature increases nearly quadratically with the increase in the temperature from the present through the next two centuries. 相似文献