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471.
Di-octyl phthalate (DOP) is widely used as a plasticizer in the plastics industry. As a result, DOP is often found in marine water ecosystems where many species are exposed to it. Our objective was to evaluate the effect of long-term (14 d) DOP exposure (2.6, 7.8, or 31.2 mg/L) on the expression of immunerelated genes in Tegillarca granosa. The expression of small heat shock protein (sHSPs) and tissue inhibitor of metalloproteinase (TIMP) were highest in clams exposed to 31.2 mg/L DOP on days 7 and 14. The relative expression of Tg-ferritin, superoxide dismutase (SOD), and metallothionein (MT) increased initially then decreased as the concentration of DOP increased. The hemoglobin of T. granosa (Tg-HbI) exhibited two distinct expression patterns at two time points. Our results suggest that the immune response of T. granosa against DOP pollution varies depending on the dose. Additionally, we identified some immune-related genes that are promising candidates for biomarkers of DOP. 相似文献
472.
Projected Shifts in Kppen Climate Zones over China and Their Temporal Evolution in CMIP5 Multi-Model Simulations 总被引:2,自引:0,他引:2
Previous studies have examined the projected climate types in China by 2100. This study identified the emergence time of climate shifts at a 1?scale over China from 1990 to 2100 and investigated the temporal evolution of K o¨ppen–Geiger climate classifications computed from CMIP5 multi-model outputs. Climate shifts were detected in transition regions(7%–8% of China's land area) by 2010, including rapid replacement of mixed forest(Dwb) by deciduous forest(Dwa) over Northeast China, strong shrinkage of alpine climate type(ET) on the Tibetan Plateau, weak northward expansion of subtropical winterdry climate(Cwa) over Southeast China, and contraction of oceanic climate(Cwb) in Southwest China. Under all future RCP(Representative Concentration Pathway) scenarios, the reduction of Dwb in Northeast China and ET on the Tibetan Plateau was projected to accelerate substantially during 2010–30, and half of the total area occupied by ET in 1990 was projected to be redistributed by 2040. Under the most severe scenario(RCP8.5), sub-polar continental winter dry climate over Northeast China would disappear by 2040–50, ET on the Tibetan Plateau would disappear by 2070, and the climate types in 35.9%and 50.8% of China's land area would change by 2050 and 2100, respectively. The results presented in this paper indicate imperative impacts of anthropogenic climate change on China's ecoregions in future decades. 相似文献
473.
通过对南极乔治王岛柯林斯冰帽小冰穹冰心100个样品的化学分析结果进行R型因子分析,将主要环境信息归结到四个因子上,解释总变量方差的99.17%.F1因子特征值为3.775,解释变量方差的41.95%,为K+、Mg2+、Ca2+、SO42-组合,主要代表了陆源杂质的输入;F3因子特征值为3.338,解释变量方差的37.09%,为Na+、Cl-、Br-组合,代表了海源杂质的输入;F2因子特征值为1.030,解释变量方差的11.44%,代表NH4+离子的输入;F4因子特征值为0.782,解释变量方差的8.69%,代表NO3-离子的输入。通过考察代表不同环境的各因子的因子得分值随冰心深度的变化趋势,研究了可溶杂质输入随时间的变化关系。 相似文献
474.
A method to predict typhoon waves 总被引:2,自引:0,他引:2
Yang Chuncheng Dai Mingrui Gao Zhihu Cheng Zhan Xu Fuxiang Liu Yu Li Fengjin Li Jie Su Dongfu Zhang Dacuo Xu Qichun 《海洋学报(英文版)》1995,14(2):167-180
Amethodtopredicttyphoonwaves¥YangChuncheng;DaiMingrui;GaoZhihua;ChengZhan;XuFuxiang;LiuYu;LiFengjin;LiJie;SuDongfu;ZhangDacuo... 相似文献
475.
中国海区及邻域的地磁场分析 总被引:3,自引:1,他引:3
戴勤奋 《海洋地质与第四纪地质》1997,17(2):63-72
本文根据中国海区及邻城的地磁场分布特征,给地质及其它物探资料,对陆块碰撞过渡带的存在性问题,东沙-澎湖磁力高带的来源问题,东亚陆缘盆地磁异常分异的原因问题进行了讨论,最后将中国海区及邻域的基底划分为六大基底岩相区。 相似文献
476.
477.
Zhou Xireng Duan Xudong Sang Xuezhu Zhang Rui Dai Jialu Professor Tianjin University Tianjin
Engineer Xiamen Port Office Fujian
Lecturer Tianjin University Tianjin
Senior Engineer Tianjin Port Office Tianjin 《中国海洋工程》1992,(2)
A method of coupled BEM-FEM analysis for the elastic spatial structure system is presented. It can be applied to the calculation of the stress and deformation of the large-diamater cylinder structure system and it is suitable for symmetric or non-symmetric structures under the distributed or concentrated load. Numerical examples show that the proposed method and computer program BEFEM are quite efficient in the analysis of the large-diameter cylinder structure problems in ocean engineering. 相似文献
478.
An automatic flow analysis system with on-line liquid nitrogen trap, hydride generation and flame-less atomic absorption spectrophotometry was presented for the determination of inorganic arsenic and antimony in seawater. The experimental conditions such as acidity of reduction reaction, the amount of sodium borohydride , the flow rate of carry gas (high purity of nitrogen) were tested and selected optimally. The limit detection of the method presented was 0. 15 ug/L for arsenic and 0. 24 μ/L for antimony . During the determination of seawater samples with levels microgram arsenic and antimony pa litre th?variation coefficient would be ±4% for arsenic and ±10% for antimony. The volume needed for one measurement was 9 mL for arsenic and 12 mL for antimony. The frequency of sample determination reached 20 times per hour for arsenic and 15 times per hour for antimony. 相似文献
479.
Genetical study on the parthenogenesis in Laminaria japonica 总被引:3,自引:0,他引:3
The parthenogenesis and natural doubling of chromosomes in wild type female gametophytes of Laminaria japonica were studied. The results indicate that not all the female gametophytes from the wild type hybrid parent can propagate through parthenogenesis. Most parthenosporophytes can mature, their spores germinate into gametophytes, the latter then developed into female sporophytes. To form these parthenosporophytes the natural doubling of chromosomes occurred mainly at the first and second cell divisions of the spores. It is thus considered that the parthenogenesis of L. japonica is inheritable and the relative genes link closely with the genes controlling the natural doubling of chromosomes and the female determination. 相似文献
480.