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1.
工业化和城市化是中国未来的两大发展趋势.以往对中国未来能源消费及碳排放的预测大都是从工业化层面出发,忽略了城市化过程导致的生活能源消费的巨大增量.推动城市化进程是提升生活质量、满足人的基本权利的重要手段;立足城市化进程,保障人均能源消费及碳排放空间是确保人人享有基本的生存权和发展权的重要基础.从对中国城市化进程的发展态...  相似文献   
2.
目前中国的碳转移排放测算方法有很多,虽然方法不尽相同,但总的结论和计算出的变化趋势类似。造成碳转移量测算结果产生较大差异的原因主要有两方面,一是碳排放强度的测算模型不同,二是对于中国加工贸易转移碳排放的认识不同。测算避免转移排放量时,如果不考虑加工贸易的影响,在某些年份(如2002年)甚至会得到"中国是碳转移的净进口国...  相似文献   
3.
Carbon isotope (δ13Corg) analyses of non-marine clastic rocks and neritic carbonates and black shales spanning the Silurian/Devonian transition are compared from two richly fossiliferous sequences in Qujing of East Yunnan and Zoige of Sichuan, South China. The two sections, Xishancun and Putonggou sections in South China, reveal positive δ13Corg shifts happening in the Upper Pridoli and Lower Devonian and reaching peak values as heavy as ?25.2‰ (Xishancun) and ?19.9‰ (Putonggou) in the lowermost Lochkovian following the first occurrence of the thelodont Parathelodus and the conodont Icriodus woschmidti woschmidti (only in Putonggou Section and together with Protathyris-Lanceomyonia brachiopod fauna). These results replicate a globally known positive shift in δ13Corg from the uppermost Silurian to the lowermost Devonian. The δ13Corg variations across the Silurian/Devonian Boundary (SDB) at the two sections in South China exhibit a shift in carbon isotopic composition similar to the detailed SDB curves from the borehole Klonk-1 drilled at top of the Klonk Global Standard Stratotype-Section and Point (GSSP) in the Prague Basin, Czech Republic. In addition, four microvertebrate assemblages, including the Liaojiaoshan, Xishancun, Yanglugou and Xiaputonggou assemblages, are recognized from the Silurian/Devonian transition exposed in the Xishancun and Putonggou sections, respectively. The results from both carbon isotope stratigraphy and microvertebrate assemblage sequences suggest that the SDB in South China is located at the base of the Xishancun Formation (between sample QX-20 and sample QX-21) in the Xishancun Section and the lower part of the Xiaputonggou Formation (between sample ZP-09 and sample ZP-10) in the Putonggou Section. The isotopic trend for organic carbon together with the changes of microvertebrate remains across the SDB can offer an approach to a potential correlation of the SDB from different sedimentary facies, which help to correlate the marine with non-marine deposits.  相似文献   
4.
介绍新型红外气体观测仪的结构、主要技术指标、优缺点以及解决其不足之处的方法;通过分析红外气体观测仪在台站试验中取得的观测数据,探索出一种将红外气体传感技术应用于断层气观测的新方法.  相似文献   
5.
FEFLOW在某市岩溶地下水四氯化碳污染中的应用   总被引:4,自引:0,他引:4  
某市是我国北方的一座大型城市,七里沟盆地是该市的三个主要岩溶水源地之一,供应该市南部20余万人的生产生活用水,2000年11月发现该岩溶含水层受到四氯化碳的污染,本文结合前人所做的工作和研究区检测资料的分析,建立了研究区水文地质概念模型和地下水数学模型,采用基于有限元方法的FEFLOW软件对模型求解,在水流模型的基础上...  相似文献   
6.
基于森林资源清查的江西省森林贮碳功能研究   总被引:2,自引:0,他引:2  
利用江西省1999--2003年森林资源二类清查资料,结合大岗山森林生态站的实测数据以及已公布的调查资料,运用材积源生物量法对江西省森林的碳储量和碳密度进行了估算和评价。结果表明,江西省不同类型森林乔木层碳密度,由大到小依次为硬阔林、针阔混交林、毛竹林、国外松林、杉木林、软阔林、灌木林、马尾松林和经济林,且碳密度随着林龄的增大而增大,随人口密度的增大而减小。森林碳密度土壤层最大,植被层次之,枯落物层最小。不同森林类型乔木层碳储量,由大到小依次为杉木林、硬阔林、马尾松林、毛竹林、灌木林、国外松林、经济林、针阔混交林、软阔林。从森林类型分布看,除杉木和国外松林外,其他森林类型天然林乔木层碳储量远大于人工林;从地理分布看,除南昌、萍乡、新余三市外,其余各市均是天然林乔木层碳储量远大于人工林。不同年龄森林乔木层碳储量,由大到小依次为中龄林、幼龄林、近熟林、成熟林、过熟林。不同森林碳储量由大到小依次为杉木林、马尾松林、硬阔林、灌木林、经济林、毛竹林、针阔混交林、国外松林和软阔林,南部和中西部要高于中东部和北部。江西省森林总碳储量为1.5Gt,占全国森林总碳储量的5.33%。  相似文献   
7.
We examined the occurrence of seasonal hypoxia (O2<2 mg l−1) in the bottom waters of four river-dominated ocean margins (off the Changjiang, Mississippi, Pearl and Rhône Rivers) and compared the processes leading to the depletion of oxygen. Consumption of oxygen in bottom waters is linked to biological oxygen demand fueled by organic matter from primary production in the nutrient-rich river plume and perhaps terrigenous inputs. Hypoxia occurs when this consumption exceeds replenishment by diffusion, turbulent mixing or lateral advection of oxygenated water. The margins off the Mississippi and Changjiang are affected the most by summer hypoxia, while the margins off the Rhône and the Pearl rivers systems are less affected, although nutrient concentrations in the river water are very similar in the four systems. Spring and summer primary production is high overall for the shelves adjacent to the Mississippi, Changjiang and Pearl (1–10 g C m−2 d−1), and lower off the Rhône River (<1 g C m−2 d−1), which could be one of the reasons of the absence of hypoxia on the Rhône shelf. The residence time of the bottom water is also related to the occurrence of hypoxia, with the Mississippi margin showing a long residence time and frequent occurrences of hypoxia during summer over very large spatial scales, whereas the East China Sea (ECS)/Changjiang displays hypoxia less regularly due to a shorter residence time of the bottom water. Physical stratification plays an important role with both the Changjiang and Mississippi shelf showing strong thermohaline stratification during summer over extended periods of time, whereas summer stratification is less prominent for the Pearl and Rhône partly due to the wind effect on mixing. The shape of the shelf is the last important factor since hypoxia occurs at intermediate depths (between 5 and 50 m) on broad shelves (Gulf of Mexico and ECS). Shallow estuaries with low residence time such as the Pearl River estuary during the summer wet season when mixing and flushing are dominant features, or deeper shelves, such as the Gulf of Lion off the Rhône show little or no hypoxia.  相似文献   
8.
Detailed data on seagrass distribution, abundance, growth rates and community structure information were collected at Orman Reefs in March 2004 to estimate the above-ground productivity and carbon assimilated by seagrass meadows. Seagrass meadows were re-examined in November 2004 for comparison at the seasonal extremes of seagrass abundance. Ten seagrass species were identified in the meadows on Orman Reefs. Extensive seagrass coverage was found in March (18,700 ha) and November (21,600 ha), with seagrass covering the majority of the intertidal reef-top areas and a large proportion of the subtidal areas examined. There were marked differences in seagrass above-ground biomass, distribution and species composition between the two surveys. Major changes between March and November included a substantial decline in biomass for intertidal meadows and an expansion in area of subtidal meadows. Changes were most likely a result of greater tidal exposure of intertidal meadows prior to November leading to desiccation and temperature-related stress.  相似文献   
9.
We suggest that different equations of state (EOS) algorithms can and frequently will provide very different predictions of CO2 migration following injection for sequestration. Rather than carry out an exhaustive examination of all EOS algorithms available, we elected to evaluate this general hypothesis by making detailed comparisons of simulation results of two very common EOS algorithms. We simulated and compared CO2 migration patterns using two fundamentally different EOS algorithms – Modified Redlich-Kwong EOS (MRKEOS) and Span and Wagner EOS (SWEOS). In general, the predictions of thermophysical properties for both algorithms are close, except for a contrast in the predicted fugacity coefficient of CO2, which subsequently propagates to a contrast in predicted solubility in water/brine. Typically, MRKEOS underestimates solubility of CO2 compared to both SWEOS and experimental solubility data. In simulations of CO2 migration, dissolution rates of separate-phase CO2 predicted from the two EOS algorithms were significantly different, even for small contrasts in predicted fluid properties from EOS algorithms, resulting in markedly different migration patterns.  相似文献   
10.
The effect of extraordinary degradation of phenol organics on the SnO2‐Sb2O3/Ti electrode is investigated through experimental research and theoretical analysis. The phenol organics contained 4‐chloro‐phenol, 4‐bromo‐phenol, and 2‐iodo‐phenol. At a current density of 4 mA cm–2 and an electrolysis time of 12 h, the degradation efficiency of the phenols was over 98% with a relatively short degradation time, whereas the degradation time of the PbO2/Ti electrode surpassed 40 h while delivering 100% disposal efficiency. Therefore, the effectiveness of electrochemical (EC) oxidation by the SnO2‐Sb2O3/Ti was superior to that of the PbO2/Ti electrode. At the same time, the SnO2‐Sb2O3/Ti had higher oxygen generation potential and lower electron consumption than the other electrodes. This was mainly due to the effect of the middle Sb2O3 layer, which due to its high porosity and good catalytic effect, contributed to a better catalysis than the SnO2 part.  相似文献   
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