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991.
庄翰华 《地球信息科学学报》2002,4(1):74-78
本文以台湾地区各县市“县市综合发展计划”中的土地资源部门之发展研究和策略为素材 ,从永续资源的观点分别就空间、内容、因果、说明等向度整理与解析. 相似文献
992.
993.
WANG Zhi XU Lihua SHI Yijun MA Qiwei WU Yaqi LU Zhangwei MAO Liwei PANG Enqi ZHANG Qi 《中国地理科学(英文版)》2021,(2):209-222
Land use changes have significant impacts on the carbon balance in an urban ecosystem. When there is rapid development in urbanizing regions, land use changes have a dramatic effect on vegetation carbon storage(VCS). This study investigates the impact of land use change on VCS in a period of rapid urbanization in Hangzhou, China. The results show that: 1) from 2000 to 2015, land use in Hangzhou underwent huge changes, mainly reflected in decrease in cropland and wetland and the increased settlem... 相似文献
994.
WANG Ruifang HUANG Xiaorong WANG Haihua LU Jianxue SHI Xiaotao FENG Guangpeng ZHUANG Ping 《中国海洋湖沼学报》2019,(5)
To investigate the effects of salinity on early development of Chinese mitten crab(Eriocheir sinensis),and the salinity tolerance mechanism of embryos,different developmental stages of embryos(gastrula,eyespot and pre-hatching stage),and hatched stage I zoea and megalopa,were exposed to a range of salinities(1,5,10,15(control),20,25,30,35 and 40).Hatching,survival and molting were monitored.Effects of 24-hour hypersaline(35)and hyposaline(1)stress on egg diameter,water content,Na~+/K~+-ATPase(NKA)activity,and crustacean hyperglycemic hormone(CHH)gene mRNA expression in embryos and megalopa,are reported.Embryos are more tolerant of low(≤5)than high(≥25)salinities,with optimum ranges for gastrula and pre-hatching stage embryos being 5-20,and for eyespot embryo and stage I zoea,10-20.Most megalopa can molt to the first juvenile instar by day 5 at salinities between 1 and 40,whereas molting of megalopa stages was delayed at 40.Hypersaline conditions resulted in a loss of moisture,reduction of egg volume,and a significant increase in NKA activity and CHH mRNA expression at some developmental stages.Hyposaline conditions did not affect moisture content or egg volume,but resulted in decreased NKA activity and CHH mRNA expression in embryos.For megalopa stages,NKA activity was significantly upregulated following both hypo-and hypersaline stress.Our results suggest high salinity will inhibit development and hatching of E.sinensis embryos,and low salinity will affect the survival of their stage I zoea.Increased NKA activity in embryos and megalopa stages might indicate a hyporegulation response under hypersaline conditions.These findings provide useful information for spawning ground protection of indigenous E.sinensis and enrich the knowledge of embryonic tolerance mechanisms of hyperregulating crustaceans following osmotic stress. 相似文献
995.
REN Guoyan) ) LI Bafang) * ZHAO Xue) ZHUANG Yongliang) YAN Mingyan) HOU Hu) ZHANG Xiukun) CHEN Li)) Food Bioengineering Department Henan University of Science Technology Luoyang P. R. China ) College of Food Science Engineering Ocean University of China Qingdao P. R. China 《中国海洋大学学报(英文版)》2009,8(1)
In order to select an optimum extraction method for the target glycoprotein (TGP) from jellyfish (Rhopilema esculentum) oralarms, a high performance liquid chromatography (HPLC)–assay for the determination of the TGP was developed. Purified target glycoprotein was taken as a standard glycoprotein. The results showed that the calibration curves for peak area plotted against concentration for TGP were linear (r = 0.9984, y = 4.5895x+47.601) over concentrations ranging from 50 to 400 mgL-1. The mean extraction... 相似文献
996.
WANG Liwei ZHANG Mingjun WANG Shengjie Athanassios AARGIRIOU WANG Gaofei Vasileios SALAMALIKIS SHI Mengyu JIAO Rong 《中国地理科学(英文版)》2020,(1):180-188
Stable oxygen isotopes in precipitation contain meaningful environmental information on a synoptic scale and can be applied to diagnose hydrometeorological processes.A series of rainstorms occurred at the southern Tianshan Mountains during the period from May to June 2013,and the event-based precipitation was sampled along the mountain range from west to east.Based on δ18 O values in precipitation samples as well as the corresponding meteorological parameters,the moisture transport paths during the sampling period were identified.In late-May(stage 1),isotopes in precipitation collected generally showed a depleting trend.In mid-June(stage 2),there was no coherent trend of isotopes in precipitation for these stations,and only isotope values in Aksu showed a continually depleting trend.Checking other meteorological proxies during the sampling period,the event-based precipitation isotopes sensitively reflected the moisture process.In central Asia,both the westerly and monsoon moisture can be delivered to cause extreme precipitation events,and the isotopic information provides an alternative tool to investigate the atmospheric processes. 相似文献
997.
998.
本文首次采用JCZ-1型地震仪观测资料研究地球环型自由振荡, 并在2011年日本9.0级地震、 2010年智利8.8级地震和2005年印尼8.6级地震后武汉地震台JCZ-1型地震仪观测到了其激发的环型自由振荡, 从中检测了基振型0T2~0T67和一次振型 1T2~1T50等振型的本征周期, 与PREM的理论值比较, 误差比小于0.5%, 补充了PREM中未提到的几次振型的本征周期: 0T11、 0T15、 0T19、 1T4、 1T5、 1T14, 并观测到了日本地震 0T2、 0T6、 0T7和 0T8振型的多峰值现象。 研究结果表明, JCZ-1型地震仪具有良好的观测超低频长周期地球自由振荡的能力。 相似文献
999.
1000.
The possible changes of extreme climates over China under 1.5 ℃ global warming scenario were investigated by using the output of CORDEX (COordinated Regional Downscaling Experiment) experiments with a regional air-sea coupled model FROALS over East Asia domain. Results indicated that compared to the baseline period of 1986-2005, warm events would significantly increase while cold events would significantly decrease over China in a 1.5 ℃ warmer world. The risks of extreme and moderate warm events would be 2.14 and 1.93 times of that in the baseline period, respectively. The risks of extreme and moderate cold events would be 0.58 and 0.63 times of that in the baseline period, respectively. Compared to other sub-regions, the increasing amplitude of extreme warm events would be higher in North China, while the decreasing amplitude of extreme cold events would be higher in Northeast China. Risks of extreme dry events would increase in Northwest China, Tibetan Plateau and Northeast China (1.13, 1.02 and 1.22 times of that in baseline period). Precipitation intensity and extreme wet events would increase significantly over most parts of China, and the increasing amplitudes extreme wet events will be higher in North China and South China (1.88 and 1.85 times of that in the baseline period). Days when people may feel uncomfortable would increase significantly in eastern China, and compared to simple extreme warm events, the increasing amplitude of extreme uncomfortable days would be larger. The absolute changes of heating degree-days would be larger than that of cooling degree-days (-258℃·d and 72℃·d, respectively) in eastern China, but the relative change of heating degree-days would be smaller than cooling degree-days (-10% and 82%, respectively). 相似文献