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931.
国有企业的改制是国家产业结构的调整、国有资产的保值增值等的必然,改制最核心的问题在于企业真实价值确认。而企业真实价值确认审计,是价值确认中的重要一环。分析了帐面价值、无形资产、评估方法等对企业价值评估的影响,总结了价值审计中应重点关注的帐面资产、无形资产以及管理层收购等方面应注意的问题与应采取的措施。  相似文献   
932.
经过四分量钻孔应变观测的实地相对标定[1]以后,将应变观测值与理论值进行拟合,使得观测值与理论值之间的相关性最大,发现观测值与理论值之间存在相位差。通过计算得出了相位差在时间上的表现形式,即时间滞后。我们计算了佘山、江宁、攀枝花、乐都、格尔木、湟源和门源7个台站的滞后时间,发现靠海较近的佘山和江宁台的体应变时间滞后分别为0.37和0.80小时,而其他5个内陆台站的体应变滞后时间大约在1.2~1.5小时以内,这可能说明海洋负荷潮对佘山和江宁的体应变影响较明显。各台站之间的差应变以及同一台站不同方向上的差应变都存在较大差异,个别台站的差应变出现相位超前的现象。  相似文献   
933.
Liu  Qian  Cao  Ziqi  Sheng  Lifang  Diao  Yina  Wang  Wencai  Zhou  Yang  Qiu  Jingyi 《Theoretical and Applied Climatology》2018,132(3-4):1117-1127
Theoretical and Applied Climatology - The summer monsoon has recently been hypothesized to influence haze-fog events over China, but the detailed processes involved have yet to be determined. In...  相似文献   
934.
Iron deficiency chlorosis of Lilium davidii var. unicolor is often the case in practice in alkaline soils of northwest region of China. It is difficult to control iron chlorosis because of high cost and short effective work time of conventional iron fertilizers. In this study, a 2-year field experiment was conducted to evaluate the effects of two slow-release fertilizers on the suppression of iron deficiency chlorosis, soil chemical properties, and the yield and quality of L. davidii var. unicolor. Results show that both coated slow-release iron fertilizers and embedded slow-release iron fertilizer effectively controlled iron-deficiency chlorosis. The application of slow-release iron fertilizers significantly increased plant height and chlorophyll content of L. davidii var. unicolor at different growth stages. Furthermore, coated iron fertilizer application significantly increased starch, protein, soluble sugar and vitamin C content of L. davidii var. unicolor, and it also significantly improved total amino acid content, with increases in essential amino acids(Trp, Leu, Lys, Phe, Val, and Thr contents) and in nonessential amino acids(Asp, Glu, Cit, Ihs, Acc, Ala, Pro, and Cys contents). It was concluded that application of coated slow-release iron fertilizer could be a promising option for suppression of iron deficiency chlorosis and deserves further study.  相似文献   
935.
王敏  朱竑  王盈盈  丘小静  曹伟  朱绘霖 《地理科学》2018,38(12):2006-2013
以广州市永庆坊为例,研究采用内隐联想测验法、问卷以及质性访谈相结合的方法,探究其改造前后社区相关主体的社区感知,旨在探讨社区空间变化背后相关主体的感知态度差异。研究结果揭示了社区感知的外显态度和内隐态度的分离效应,且外显态度表现的差异性强于内隐态度。参与者对永庆坊改造前后的连贯性和积极性存在外显感知态度的显著差异,在内隐态度结果上,参与者对永庆坊改造前后的连贯性和积极性并未存在显著差异。实验结果表明:物质层面的更新并非引起居民等主体对改造热议的根本原因,社区更新重点应关注利益主体对权利、参与权的诉求,关注其利益分配的合理性。诚然,社区改造规划中不仅应重视公众参与和调查,也应深入挖掘社区公众对于社区改造的内隐感知态度,以提高社区规划的效力。研究采用内隐联想测验的神经科学认知方法对景观感知的探讨,以期开拓人文地理学研究方法神经科学转向的新方向。  相似文献   
936.
937.
The nature and characteristics of the mixed layer depth (MLD) remain uncertain in the northern South China Sea. Using in situ data, we examined the quality of different MLD definitions, investigated the spatial and diurnal variation in the MLD, and examined the mechanisms of mixed layer development during March 23–31, 2014. We made distinct calculations of the MLD; of which two are (a) the depths between two different temperatures (0.2, 0.6 °C) and (b) the depths between two density differences (0.125, 0.25 kg/m3); and the fifth calculation is a depth derived from the optimal linear fitness method. We found that the optimal linear fitness MLD was the best definition for our study region ,and that it deepened from the shelf to the slope. Twenty-four-hour diurnal variation in the MLDs and mixing layers was observed when the ship was moored. Mixing layers were characterized by turbulent dissipation rates. We found that the mixed layer underwent a ‘stable-decaying–developing’ process. During the stable period, the MLD was close to that of the mixing layer, but during the decay/development periods, the MLDs were larger/smaller than those of the mixing layers. We suggest that both velocity shear and buoyancy flux were important in mixed layer development. We quantitatively examined the mechanisms of mixing in the shelf region, with air–sea net heat flux determined to be the major factor, rather than wind speed or current velocity.  相似文献   
938.
939.
Forest restoration policies are often implemented without the assessment of their full environmental impact. In this study, we investigated the challenges of vegetation greening resulted from forest restoration on water resource sustainability, using a model‐based simulation in northwestern China. Four different vegetation scenarios and 25 future climate scenarios were employed using the Soil and Water Assessment Tool model. Results suggest that (a) the mean annual evapotranspiration changes from only 7.2% in the barren case to 100% in the forest case; however, it produced a 35.2% reduction in average annual streamflow and a 157% increase in soil water storage. The upstream vegetation greening caused the enhancement of water retention, while also creating great challenges for future downstream water resource sustainability; (b) seasonal effect was significant in that 100% forest case increased evapotranspiration (+40%) but it also reduced the streamflow (?73%) compared to the barren case in growing season, which may exacerbate spring and summer drought; (c) changes of evapotranspiration and streamflow were only 0.3% and ?0.9% at T + 3.9 °C when compared to the historic scenario in barren cases, while for all forest cases, variations were 3% and ?21.8%, respectively; (d) vegetation greening induced more remarkable changes in hydrological components than those resulting from climate change. Our “what if” research provides new insights for promoting sustainable management of water resources and ecosystems in mountainous water source areas.  相似文献   
940.
Southern Cross, where gold deposits are sited in narrow greenstone belts surrounding granitoid domes, was one of the earliest gold mining centres in Western Australia. SHRIMP U–Pb zircon and Pb‐isotope studies of the largest granitoid dome, the Ghooli Dome (80 × 40 km), provide important constraints on the crustal evolution and structural history of the central part of the Archaean Yilgarn Craton, Western Australia, which includes Southern Cross. The north‐northwest‐south‐southeast‐oriented ovoid Ghooli Dome has a broadly concentric foliation that is subhorizontal or gently dipping in its central parts and subvertical along its margins. Foliated granitoids in the dome are dated at ca 2724 ± 5 and 2688 ± 3 Ma using the SHRIMP U–Pb zircon and Pb–Pb isochron methods, respectively. These new data, together with the published SHRIMP U–Pb zircon age of 2691 ± 7 Ma at another locality, 20 km from the centre of the Koolyanobbing Shear Zone, suggest that the Ghooli Dome was emplaced at ca 2.72–2.69 Ga. Because the Ghooli Dome and the other domes, which are enveloped by narrow greenstone belts, are cut by the >650 km‐long and 6–15 km‐wide Koolyanobbing Shear Zone, the ca 2.69 Ga age is interpreted as the maximum age of the last major movement on this structure. The pre‐2.69 Ga history, if any, of the shear zone remains unknown. The shear zone is intruded by an undeformed porphyritic granitoid which has a SHRIMP U–Pb zircon age of 2656 ± 4 Ma. This age is, thus, the minimum age of major movement along this shear zone. Post‐gold mineralisation pegmatitic‐leucogranite from the Nevoria gold mine has a SHRIMP U–Pb zircon age of 2634 ± 4 Ma, with xenocrystic zircon cores of ca 2893 ± 6 Ma, constraining the minimum age of gold mineralisation there to ca 2.63 Ga. The ca 2.72–2.69 Ga granitoids also contain ca 2.98 and 2.78 Ga xenocrystic zircon cores, suggesting an extensive crustal prehistory for their source. Whereas there is a general temporal relationship between the periods of older (ca 3.0 Ga) and younger (ca 2.80 and 2.73 Ga) volcanism and the older (2.98, 2.78 and 2.72–2.69 Ga) granitoid intrusions, there is no known volcanism temporally associated with the 2.65–2.63 Ga granitoid intrusions in the Yilgarn Craton. Other heat sources and/or tectonic processes, required for the generation of these intrusions, are interpreted to be related to a lithospheric delamination event related to continental collision.  相似文献   
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