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121.
Wang Huijun 《大气科学进展》2009,26(4):613-613
Climate change is one of the most challenging issues faced by human beings. Although many remarkable achievements have been made in climate change research,there is still a tremendous amount of uncertainty in 相似文献
122.
Policy-makers of some fossil fuel-endowed countries wish to know if a given fossil fuel supply project is consistent with the global carbon budget that would prevent a 2 °C temperature rise. But while some studies have identified fossil fuel reserves that are inconsistent with the 2 °C carbon budget, they have not shown the effect on fossil fuel production costs and market prices. Focusing on oil, we develop an oil pricing and climate test model to which we apply future carbon prices and oil consumption from several global energy-economy-emissions models that simulate the energy supply and demand effects of the 2 °C carbon budget. Our oil price model includes key oil market attributes, notably upper and lower market share boundaries for different oil producer categories, such as OPEC. Using the distribution of the global model results as an indicator of uncertainty about future carbon prices and oil demand, we estimate the probability that a new investment of a given oil source category would be economically viable under the 2 °C carbon budget. In our case study of Canada’s oil sands, we find a less than 5% probability that oil sands investments, and therefore new oil pipelines, would be economically viable over the next three decades under the 2 °C carbon budget. Our sensitivity analysis finds that if OPEC agreed to reduce its market share to 30% by 2045, a significant reduction from its steady 40–45% of the past 25 years, then the probability of viable oil sands expansion rises to 30%. 相似文献
123.
Devleena Mani T. Satish Kumar M. A. Rasheed D. J. Patil A. M. Dayal T. Gnaneshwar Rao V. Balaram 《Natural Resources Research》2011,20(1):75-88
The association of iodine with organic matter in sedimentary basins is well documented. High iodine concentration in soils
overlying oil and gas fields and areas with hydrocarbon microseepage has been observed and used as a geochemical exploratory
tool for hydrocarbons in a few studies. In this study, we measure iodine concentration in soil samples collected from parts
of Deccan Syneclise in the west central India to investigate its potential application as a geochemical indicator for hydrocarbons.
The Deccan Syneclise consists of rifted depositional sites with Gondwana–Mesozoic sediments up to 3.5 km concealed under the
Deccan Traps and is considered prospective for hydrocarbons. The concentration of iodine in soil samples is determined using
ICP-MS and the values range between 1.1 and 19.3 ppm. High iodine values are characteristic of the northern part of the sampled
region. The total organic carbon (TOC) content of the soil samples range between 0.1 and 1.3%. The TOC correlates poorly with
the soil iodine (r
2 < 1), indicating a lack of association of iodine with the surficial organic matter and the possibility of interaction between
the seeping hydrocarbons and soil iodine. Further, the distribution pattern of iodine compares well with two surface geochemical
indicators: the adsorbed light gaseous hydrocarbons (methane through butane) and the propane-oxidizing bacterial populations
in the soil. The integration of geochemical observations show the occurrence of elevated values in the northern part of the
study area, which is also coincident with the presence of exposed dyke swarms that probably serve as conduits for hydrocarbon
microseepage. The corroboration of iodine with existing geological, geophysical, and geochemical data suggests its efficacy
as one of the potential tool in surface geochemical exploration of hydrocarbons. Our study supports Deccan Syneclise to be
promising in terms of its hydrocarbon prospects. 相似文献
124.
改革开放以来中国农业政策效果的时空计量分析 总被引:1,自引:0,他引:1
Since reform and opening up, how much contribution has China’s implementation of new agricultural policy made to agricultural output? This paper is trying to establish an agricultural policy output econometric model for doing a quantitative analysis of China’s new agricultural policy. The results show that China’s agricultural policies on agricultural output have an average contribution rate of about 7% since 1978, which is consistent with the OECD’s basic forecast. There are obvious temporal and spatial differences. Generally speaking, we can divide the contribution of agricultural policy into three periods, which are the start-up phase from 1978 to 1991 (14 years), the stationary phase from 1992 to 2002 (11 years) and the rising phase from 2003 to 2008 (6 years). In space, the contribution of agricultural policy underwent a process from the all-low in the start-up phase, the gradual increase in the stationary phase to the all-high in the rising phase. Northern and western regions are more sensitive to policies. There are three major factors that can affect the contribution of regional agricultural policies, which are the process of national industrialization strategy, terrain and the level of local finance. 相似文献
125.
Unlike other branches of geosciences, exploratory drilling has not been investigated within the framework of an information
system; so, the expression “value of exploratory drilling information” (despite its common usage) is vague. This article presents
a model for the evaluation of value of the information gathered from exploratory drilling after studying different mineral
exploration and exploratory drilling systems within the framework of an “information system.” Although this model does not
present the economic value of information, it is a suitable tool for comparing different drilling patterns. The model was
verified on the basis of drilling data for the Gol-Gohar XIIA anomaly. 相似文献
126.
127.
The Haji-Gak iron deposit of eastern Bamyan Province, eastern Afghanistan, was studied extensively and resource calculations
were made in the 1960s by Afghan and Russian geologists. Recalculation of the resource estimates verifies the original estimates
for categories A (in-place resources known in detail), B (in-place resources known in moderate detail), and C1 (in-place resources estimated on sparse data), totaling 110.8 Mt, or about 6% of the resources as being supportable for the
methods used in the 1960s. C2 (based on a loose exploration grid with little data) resources are based on one ore grade from one drill hole, and P2 (prognosis) resources are based on field observations, field measurements, and an ore grade derived from averaging grades
from three better sampled ore bodies. C2 and P2 resources are 1,659.1 Mt or about 94% of the total resources in the deposit. The vast P2 resources have not been drilled or sampled to confirm their extent or quality. The purpose of this article is to independently
evaluate the resources of the Haji-Gak iron deposit by using the available geologic and mineral resource information including
geologic maps and cross sections, sampling data, and the analog-estimating techniques of the 1960s to determine the size and
tenor of the deposit. 相似文献
128.
129.
The level of Cliff Lake, a small, subalpine, moraine-dammed lake in California’s south central Sierra Nevada, was approximately
5 m lower than present for 50 years or more approximately 600 years ago, this determined by radiocarbon dating of wood recovered
from a submerged tree stump found in the lake. This finding corresponds to commensurate data from throughout much of western
North America, suggesting the duration and magnitude of terminal medieval megadrought was similar throughout the region. Ultimately
this datum helps give credence to the perspective that though late Holocene climate in California was indeed variable, the
effects of terminal Medieval megadrought was similar across both time and broad geographic expanse. 相似文献
130.
W. Earl Bardsley 《Natural Resources Research》2008,17(4):197-204
A sustainable global silicon energy economy is proposed as a potential alternative to the hydrogen economy. This first visualization
of a silicon energy economy is based on large-scale and carbon-neutral metallic silicon production from major smelters in
North Africa and elsewhere, supplied by desert silica sand and electricity from extensive solar generating systems. The resulting
“fuel silicon” is shipped around the world to emission-free silicon power stations for either immediate electricity generation
or stockpiling. The high energy density of silicon and its stable storage make it an ideal material for maintaining national
economic functioning through security of base load power supply from a renewable source. This contrasts with the present situation
of fossil fuel usage with its associated global warming and geopolitical supply uncertainties. Critical technological requirements
for the silicon economy are carbon-neutral silicon production and the development of efficient silicon-fired power stations
capable of high-temperature rapid oxidation of fuel silicon. A call is made for the development of research effort into these
specific engineering issues, and also with respect to large-scale economical solar power generation. 相似文献