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981.
在我国发现的Schwertmannite矿物及其特征 总被引:5,自引:1,他引:5
采用X射线衍射(XRD)、扫描电镜与能谱(SEM-EDX)、X射线荧光(XRF)、傅立叶红外光谱(FT-IR)、热分析(DTA-TG)等分析方法,在我国山西马兰煤矿的酸性矿坑排水(AMD)沉淀物中首次发现了“斯沃特曼铁矿”(Schwertmannite)。研究表明,山西马兰煤矿酸性矿坑排水沉淀物中的Schwertmannite矿物的粒径为0.3~70μm,且分布比较均匀,其BET表面积为44.065 0 m2/g;SEM二次电子像显示为球形或椭圆形(聚集体)结构,颗粒大小比较均匀,球的表面有针状毛刺;该矿物的化学式为Fe8O8(OH)4.52(SO4)1.74.4.73H2O。 相似文献
982.
四川丹巴白云母矿山公园矿业遗迹资源特征及评价 总被引:1,自引:0,他引:1
四川丹巴白云母矿是我国开发最早的白云母矿之一。在悠久的开采历史中遗存下了十分丰富的矿业遗迹,成为该公园建设的基础。这些遗迹典型、稀有,系统完整,科学价值高,组合独特,具有很高的历史文化价值。此外,公园内配套的自然人文景观丰富,旅游区位条件良好,矿业遗迹开发价值巨大。 相似文献
983.
984.
湖南省界牌岭矿区水文地质条件的认识 总被引:4,自引:0,他引:4
文章论述了界牌岭矿区水文地质条件,并且根据原有资料对矿山开采中暴露的地质环境问题进行综合分析,取得了对矿区水文地质条件较全面的认识。 相似文献
985.
986.
Anong Paijitprapapon Kiattiphong Udomtanateera Orapin Udomtanateera Vanruedee Chariyapisuthi Trakool C hengsuksawat 《中国地球化学学报》2006,25(B08):253-254
Highly elevated cadmium concentrations in paddy soil in the Mae Sod District, Tak Province, Thailand, was detected and widely reported in 2003. This emergence provoked public interest and demands for responsibility and remedial actions. As zinc mines and concentrator were located in the upstream area, mining activities were proclaimed a contamination source. Department of Primary Industries and Mines (DPIM), a governmental organization responsible for mining and mineral processing, was thus challenged to verify the reliability of post monitoring data displaying consistently low heavy metal concentrations in compliance with the standard limits for over 15 years. Detailed survey and deep-going research on the causes, boundary and severity of cadmium contamination as well as the environmental impact alleviation were consequently conducted. Environmental samples were accumulated systematically for 2 years throughout the areas of upstream and downstream mining sites. A total of 259 soil samples from 53 spots at the depths of 0-20, 20-40, 40-60 and 60-200 cm were drilled with hand auger. Samples of water, stream sediment and mine tailing were also collected. Chemical analysis for cadmium (Cd), zinc (Zn) and lead (Pb) concentrations with AAS and ICP were undertaken. The contaminated area was finally defined to spread over approximately 18 square kilometer mainly of mountainous mineralizing land and colluvium. 相似文献
987.
The Development of a new Numerical Modelling Approach for Naturally Fractured Rock Masses 总被引:1,自引:3,他引:1
Summary. An approach for modelling fractured rock masses has been developed which has two main objectives: to maximise the quality
of representation of the geometry of existing rock jointing and to use this within a loading model which takes full account
of this style of jointing. Initially the work has been applied to the modelling of mine pillars and data from the Middleton
Mine in the UK has been used as a case example. However, the general approach is applicable to all aspects of rock mass behaviour
including the stress conditions found in hangingwalls, tunnels, block caving, and slopes. The rock mass fracture representation
was based on a combination of explicit mapping of rock faces and the synthesis of this data into a three-dimensional model,
based on the use of the FracMan computer model suite. Two-dimensional cross sections from this model were imported into the
finite element computer model, ELFEN, for loading simulation.
The ELFEN constitutive model for fracture simulation includes the Rotating Crack, and Rankine material models, in which fracturing
is controlled by tensile strength and fracture energy parameters. For tension/compression stress states, the model is complemented
with a capped Mohr-Coulomb criterion in which the softening response is coupled to the tensile model. Fracturing due to dilation
is accommodated by introducing an explicit coupling between the inelastic strain accrued by the Mohr-Coulomb yield surface
and the anisotropic degradation of the mutually orthogonal tensile yield surfaces of the rotating crack model. Pillars have
been simulated with widths of 2.8, 7 and 14 m and a height of 7 m (the Middleton Mine pillars are typically 14 m wide and
7 m high). The evolution of the pillar failure under progressive loading through fracture extension and creation of new fractures
is presented, and pillar capacities and stiffnesses are compared with empirical models. The agreement between the models is
promising and the new model provides useful insights into the influence of pre-existing fractures. Further work is needed
to consider the effects of three-dimensional loading and other boundary condition problems. 相似文献
988.
Stanislav Fran
ikovi-Bilinski 《Journal of Geochemical Exploration》2006,88(1-3):106
The objective of this work is to present an example of environmental impact of barite waste management observed in stream sediments of the western part of the Kupa River drainage basin. It is a significant water resource for Croatia and a part of Slovenia. In addition, it is for both countries a region of tourism, sport and fishing. Sediments (fraction < 63 μm) collected within the whole drainage basin have shown a significant barium anomaly in the western part. The highest concentration of total barium (5790 mg/kg) was determined in Kupica, a tributary of Kupa River. The barium anomaly was traced in Kupa River about 120 km downstream. Looking for the contamination source it was found that the anomaly originates from uncareful waste disposal into an abyss, after barite separation in Homer (Lokve), Gorski Kotar, Croatia. From there barite entered Kupica River subterraneous. Barite and albite were identified by XRD near the source of Kupica River as minor minerals, while quartz and dolomite ferroan were major minerals. This preliminary report does not give yet an answer about barium solubility in river water, about its bioavailability and consequently about barium pollution in the western part of the Kupa River drainage basin, however the possibility is highlighted and discussed. 相似文献
989.
Nurlidia Mansor Ian D. Pulford Angus B. MacKenzie 《中国地球化学学报》2006,25(B08):23-23
Tyndrum was an industrial mining area from 1741 until the 1920s where the main ores extracted were lead sulphide (galena) and zinc sulphide (sphalarite). Situated in central Scotland, the now deserted site is identified as a highly polluted, barren area where the original waste residues from the mine, an ore processing and a smelting site are clearly evident. Previous studies have suggested that high levels of lead and zinc contaminants are still dispersed from this former mine site, both atmospherically and through fluvial transport. For example, high concentrations of Pb, identified by its isotopic signature as originating in Tyndrum, have been found in sediments in Loch Tay, 25 km east of this area. This paper presents the results of a study of the occurrence and magnitude of airborne contamination by dispersion from the former mine site using measurements of metal concentrations in tree bark. These naturally occurring ‘bio monitors', which accumulate airborne materials including heavy metals, have become an effective alternative to the more costly air-filter system, which is restricted in scope and coverage. Bark samples were acquired from Scots pine (Pinus sylvestris) trees, which are abundant around the derelict mine site. Suitable locations were chosen to investigate atmospheric transport and deposition of contaminants within the area. 相似文献
990.
Mineshi Sakamoto Xinbin FENG Ping LI Guangle QIU Hongmei JIANG Minoru Yoshida Toyoto Iwata Xiaojie LIU Katsuyuki Murata 《中国地球化学学报》2006,25(B08):42-43
Objectives: To assess the exposure to elemental mercury (Hg0) vapor and methylmercury (MeHg) among mercury mine workers in an area of Guizhou Province, China. Methods: Urine total mercury (THg) and hair THg and MeHg were measured in 26 mercury miners and smelters (i.e., exposed group), and 52 control subjects (unexposed group). Results: The mine workers showed high geometric mean THg concentrations in urine (258 ng/mL, 226 μg/g creatinine) and hair (20.0 μg/g). The urine Hg level of smelters, in particular, was extremely high (338 μg/g creatinine in urine). The highest urine THg reached 4580 μg/g creatinine. THg concentrations in urine and hair showed a significant correlation in the exposed group (r=0.62), indicating the adhesion of HgO vapor to hair. However, no such significant correlation was found in the control group. 相似文献