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291.
Carbon leakage is central to the discussion on how to mitigate climate change. The current carbon leakage literature focuses largely on industrial production, and less attention has been given to carbon leakage from the electricity sector (the largest source of carbon emissions in China). Moreover, very few studies have examined in detail electricity regulation in the Chinese national emissions trading system (which leads, for example, to double counting) or addressed its implications for potential linkage between the EU and Chinese emissions trading systems (ETSs). This article seeks to fill this gap by analysing the problem of ‘carbon leakage’ from the electricity sector under the China ETS. Specifically, a Law & Economics approach is applied to scrutinize legal documents on electricity/carbon regulation and examine the economic incentive structures of stakeholders in the inter-/intra-regional electricity markets. Two forms of ‘electricity carbon leakage’ are identified and further supported by legal evidence and practical cases. Moreover, the article assesses the environmental and economic implications for the EU of potential linkage between the world’s two largest ETSs. In response, policy suggestions are proposed to address electricity carbon leakage, differentiating leakage according to its sources.
Key policy insights
Electricity carbon leakage in China remains a serious issue that has yet to receive sufficient attention.
Such leakage arises from the current electricity/carbon regulatory framework in China and jeopardizes mitigation efforts.
With the US retreat on climate efforts, evidence suggests that EU officials are looking to China and expect an expanded carbon market to reinforce EU global climate leadership.
Given that the Chinese ETS will be twice the size of the EU ETS, a small amount of carbon leakage in China could have significant repercussions. Electricity carbon leakage should thus be considered in any future EU–China linking negotiations.
292.
A fractal in general is a scale-invariant object that has an underlying power-law equation and is characterized by a positive fractal dimension. The fractal dimension of the Indian landmass is evaluated from the lineament map by utilizing the MATLAB programme for box counting method. The lineament map of India is divided into grids. The fractal dimension of each grid is obtained and the values are mapped. Most of the regions of India has fractal dimension in the range 1–1.25. The fractal values are compared with b-value in Gutenberg–Richter equation which gives a relationship between frequency of occurrence of earthquake and its magnitude. The estimation of b-value requires a complete earthquake dataset. In regions where the complete earthquake data are not available, the fractal dimension evaluated from the study can be used as a parameter to assess the seismic hazard of the region. 相似文献
293.
The morphology and toxicity of Pseudo-nitzschia strain PP0201-01, isolated near the estuary of Changjiang (Yangtze) River in Year 2002 and tentatively identified as Pseudo-nitzschia pungens, were studied. The strain was identified morphologically as P. pungens using scanning electronic microscope (SEM). The analytical results of LC-PDA (liquid chromatography with photodiode array detector), LC-MS (liquid chromatography with mass detector), and the toxicity data from mouse bioassay, showed that no domoic acid was produced by the strain. However, the mechanism of domoic acid production by Pseudo-nitzschia species is complicated. More works are needed to assess the toxic species and to evaluate the potential risk of amnesic shellfish poisoning (ASP) in China. 相似文献
294.
以美国怀俄明州钠基(MX80)膨润土为研究对象,采用热探针法测定碱−热环境下MX80膨润土的导热系数,探讨了温度、碱液强度和干密度对试样导热系数λ的影响规律,并选择部分试样进行了X射线衍射(X-ray diffraction,简称XRD)和扫描电镜(scanning electron microscope,简称SEM)试验,揭示了碱−热环境下MX80膨润土导热性能演变的微观机制。试验结果表明:MX80膨润土的导热系数λ随碱液含量和干密度的递增而增大;在不同碱液含量条件下,膨润土的导热系数均随温度升高而增大,且碱液含量越高,导热系数的温度效应越显著;干密度较小时,膨润土导热系数λ随温度升高而增大的影响越明显,主要原因是温度促进了试样内部的水汽潜热传输;同一温度和干密度条件下,热传导系数λ随着碱液pH值的升高而降低6,且pH值越高,则λ降幅越明显,主要原因是强碱溶液腐蚀了膨润土的蒙脱石成分,减少了试样内石英含量,增大了膨润土试样的孔隙率,进而降低了膨润土导热系数,这与测试试样的XRD和SEM结果相吻合。 相似文献
295.
MICP联合纤维加筋改性钙质砂的动力特性研究 总被引:1,自引:0,他引:1
为了提高我国南海钙质砂地基的抗液化性能,提出利用微生物诱导碳酸钙沉积(MICP)技术联合纤维加筋技术对钙质砂进行改性处理。通过开展动三轴试验,对比分析了改性前后钙质砂试样的动应变、动孔压、应力−应变滞回曲线以及动弹性模量的发展规律和演化特征,并结合扫描电镜(SEM)试验探究了MICP和纤维加筋技术对钙质砂的联合改性机制。研究结果表明:(1)MICP技术可以明显改善钙质砂试样的抗变形与抗液化性能,相比于未胶结处理试样,仅MICP处理试样的动应变和动孔压分别降低了95.74% 和 92.46%;(2)纤维的掺入进一步提升了MICP的改性效果,相比于仅MICP处理试样,MICP和纤维加筋联合处理试样的动应变和动孔压分别降低了 74.32%和 74.18%;(3)MICP 和纤维加筋技术通过减轻试样在循环荷载作用下的循环活动强度和能量耗散、提高试样的动弹性模量和减小动弹性模量的衰减速率,从而实现试样抗变形与抗液化性能的显著提高;(4)SEM 试验分析结果表明,MICP 与纤维对钙质砂动力特性的改善具有协同作用。纤维的掺入为细菌提供了更多的附着场所,促进了碳酸钙晶体的生成量,该部分碳酸钙不仅增加了颗粒间的胶结强度,同时也将纤维固定在砂颗粒上增强了纤维网的约束作用。 相似文献
296.
山西孝义铝土矿扫描电镜研究 总被引:2,自引:0,他引:2
本文用扫描电子显微镜和能量色散谱仪研究了山西孝义铝土矿的微观形态和结构,并与国内其他几个铝土矿略作比较。认为孝义铝土矿可分为四个地质层位,多层微观形态和结构具有明显特征。C层是一水硬铝石最富集的一层,其晶体发育程度不及河南新安铝土矿,但比广西平果铝土矿中的一水硬铝石晶体略为完整。 相似文献
297.
本文应用扫描电镜、X射线衍射(粉晶)分析、电子探针、化学分析、原子吸收光谱分析等手段研究了大吉山和瑶岗仙脉状钨矿床中黑钨矿微量元素的赋存状态、含量以及Nb、Ta在矿物中的“置换容量”等问题。大吉山6号脉及瑶岗仙501号脉黑钨矿单晶具有带状构造,结合各带的成分特点,讨论了具带状构造黑钨矿的形成条件及其成因意义。 相似文献
298.
Weidong Guo Chao Wang Yan Li Liyin Qu Muchen Lang Yongbin Deng Qinglong Liang 《地球科学进展》1986,35(9):933-947
Since 1990s, spectral analysis has become an important technique to characterize the properties of chromophoric and fluorescent dissolved organic matter (CDOM and FDOM) from various aquatic systems and a series of spectral indices have been suggested to trace the sources of DOM and their biogeochemical regulation processes. DOM samples were collected from an aquatic continuum from watershed to deep ocean, i.e. Zhangjiang River and Estuary, Dongshan Bay, Taiwan Strait, Northeast basin of the South China Sea, Luzon Strait and the vertical profile of the Kuroshio region of the West Pacific Ocean. This continuum covered many critical interfaces (land-ocean, shelf-basin, marginal sea basin-open ocean and euphotic and aphotic layer). The spatial distribution and variation of various qualitative and quantitative parameters along the continuum were clearly revealed. Combined with literature review, the sources and sinks of CDOM/FDOM and their inherent regulation processes under significant hydrological and biogeochemical gradient variation were systematically summarized. The geochemical differentiation of the quantitative DOM spectral index in various aquatic systems was discussed. The tracing ability of the qualitative DOM spectral index was commented. The coupling study of soil-river organic matter systems, mechanism of mineralization-related microbial production of CDOM/FDOM, quantified geochemical framework concept and perturbation of global change on CDOM/FDOM dynamics were suggested as future key topics. 相似文献
299.
300.
Kevin Leahy 《Bulletin of Volcanology》1997,59(1):65-71
Reworked volcaniclastics are traditionally discriminated from primary tephra-fall pyroclastics by an absence of features
such as blanketing, juvenile lapilli, grain welding and poor sorting. Frequently, these features are difficult to identify,
especially in small outcrops, ancient or altered successions, debris flows and surge deposits. Crystal-rich volcaniclastics,
such as kimberlites, have a large proportion of coarse euhedral crystals, and abrasion leading to rounding can be recognised
and classified with relative ease. A petrographic method of discriminating reworked material has been devised, based on the
degree of grain roundness, and is illustrated using volcaniclastic kimberlite from Fort a la Corne, Saskatchewan, Canada.
Petrographic thin sections of samples at regular intervals throughout the borehole core, and from a nearby crater-facies kimberlite,
show that the percentages of rounded, subrounded and euhedral grains define two distinct groupings. The first group contains
a higher percentage of euhedral grains and includes all the samples from the basal 4.8 m of the 14.1-m-thick kimberlite section
in borehole 004, and all of the crater facies tephra-fall tuffs. A second group contains more rounded, subrounded and fragmental
grains and includes all the data from the upper 6.3 m, which are interpreted as reworked strata. Thus, point counting concurs
with hand-sample interpretation and may be used as a verification tool in discriminating reworked pyroclastic sands from primary
tephra-fall tuffs.
Received: 27 August 1996 / Accepted: 31 May 1997 相似文献