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121.
In December 2001, acid mine drainage (AMD) from an abandoned copper mine at Britannia Beach (British Columbia, Canada) was diverted to flow from Britannia Creek into an outfall at 30 m depth in Howe Sound. Britannia Beach was studied in early 2003 to determine whether AMD diversion resulted in improved conditions for intertidal organisms. Species number and abundance have increased at the intertidal zone since AMD diversion, although they were still lower than at an unpolluted control site nearby (Furry Creek). Survivorship and growth rates of transplanted Mytilus trossulus (mussel) have increased since AMD diversion, although they were still significantly lower than at the control site. Transplanted Fucus gardneri (seaweed) performed better than before the AMD diversion; at Britannia Beach the chlorophyll a concentration in tissues was not significantly different from that at the control site, although the concentration of chlorophyll c in tissues and the chlorophyll c to a ratio was lower than at the control site six weeks after transplantation. Britannia Beach is still subject to leaching of metals from surrounding soils, low levels of AMD coming down the creek, and AMD discharge from the deep outfall. Although there has been an improvement, the intertidal environment at Britannia Beach still seems unable to support normal growth and survival of organisms. 相似文献
122.
Heavy metal pollution and acid drainage from the abandoned Balya Pb-Zn sulfide Mine,NW Anatolia,Turkey 总被引:5,自引:0,他引:5
Atilla?Aykol Murat?BudakogluEmail author Mustafa?Kumral Ali?H.Gultekin Melih?Turhan Vildan?Esenli Fuat?Yavuz Yuksel?Orgun 《Environmental Geology》2003,45(2):198-208
This study was conducted to determine the effects of the waste-rock dump (WRD) of the underground polymetallic Balya Mine on the Kocacay River and eventually on Lake Manyas in Turkey. Data presented in this paper include geochemical characteristics of various kinds of water (mine, surface and groundwater) and of suspended-particle samples in the vicinity of Balya. The more polluted mine waters have low pH and high conductivity, while high concentrations of Zn, Cd, Mn tend to be found in the dry and wet seasons. High concentrations of Pb, As, Cr, Cu and S appear only in the wet season. The sources of the heavy metal concentration within the Kocacay River are leached waste, surface run off, and overflow from the spillway of the WRD. To minimize the formation of acids and dissolved metal, and for the remediation of the harmful effects of extreme contamination conditions, it is recommended that lime or alkali materials and organic carbon be added to simulate the action of sulfate-reducing bacteria. 相似文献
123.
黄陵二号井开采煤层能否引起上畛子及百药沟水源地破坏是一个重要的环境地质问题,倍受业内人士的关注,但目前观点仍不统一。依据地质勘探资料,运用水文地质学相关理论,在分析井田水文地质特征及直罗组上段隔水性能的基础上,通过导水裂隙带最大高度计算,得出了煤层开采对水源地无影响的结论,并提出了矿井建设期间应注意的事宜。 相似文献
124.
125.
The karst paleo-sinkhole is a special geological structure widely found in the coal measures of northern China. Some paleo-sinkholes
have high permeability and connectivity, making them excellent connectors between the karst aquifer and the coal seam. Consequently,
during coal extraction disastrous water inrushes take place frequently, which cause severe loss not only in mine submersions
and personnel casualties, but also in environmental quality. Locations and the geological and hydrogeological characteristics
of paleo-sinkholes in northern China are presented. In-situ drilling and excavation results show that paleo-sinkholes have
different hydrogeological behaviors in different regions and in different mines. Based on observed data, mining-induced strata
failure in the seam floor is analyzed. The existence of paleo-sinkholes increases the floor strata failure zone. Numerical
simulation then is adopted to model coal mining with the effects of both the paleo-sinkholes and the water pressure in the
confined aquifer. Analyses of the simulation conclude that the paleo-sinkhole induces the increase in the strata failure and
deformation. These make water inrushes more likely to happen. 相似文献
126.
Computer-based landscape evolution models offer the ability to evaluate landscape stability over the short (annual), medium
(decades to hundreds of years) and long-term (thousands of years). Modeling has advantages in that design ideas can be tested,
different surface material properties can be evaluated and risk analysis carried out. Landscape evolution models allow landscape
surface change through time. These models also offer the advantage that the landscape can be evaluated visually as it develops
through time, which is not possible with other types of models. Landscape evolution models can be used for not only soil loss
assessment (i.e. tonnes/hectare/year), but also to evaluate the method of soil loss (i.e. rill or interrill erosion). This
study examines a range of waste rock dump designs for the Minera Alumbrera Ltd. copper mine, Argentina. An erosion assessment
using the SIBERIA erosion model over a 1000-year simulation period demonstrates waste rock dump designs using a conventional
stepped design of backsloping benches and caps with angle of repose slopes provide the lowest average erosion rates and depths
of incision than do other designs. Caution should be applied in interpreting these results as the SIBERIA erosion model is
sensitive to parameter input and in this case was calibrated and run using a generic set of parameters that are not site specific.
Nevertheless, the results provide a guide as to the strengths and weaknesses of different rehabilitation designs and demonstrate
the insights that modeling studies can provide. 相似文献
127.
煤矸石浸泡污染物溶解释放规律研究--阜新市新邱露天煤矿不同风化煤矸石在不同固液比条件下浸泡实验 总被引:2,自引:0,他引:2
论文对新邱露天矿不同风化程度的煤矸石在不同固液比条件下溶解释放污染物的规律进行了浸泡实验研究。结果表明:煤矸石溶解释放的主要污染物为总硬度(CaCO3)、硫酸盐(SO42-)、钠(Na )、总溶解性固体(TDS)、氟化物(F-)、耗氧量(OC)和总铁(Fe)等,氯化物(Cl-)、锰(Mn)、锌(Zn)等少量,其它重金属和砷等微量。pH值接近中性。煤矸石风化程度越高,溶解释放的无机盐类污染物量越多,新鲜混合煤矸石溶解释放出较高的氟化物(F-)、耗氧量(OC)和总铁(Fe);固液比对煤矸石中污染物的溶解释放有重要影响。固液比越小,浸泡液中污染物浓度越低,越有利于煤矸石中污染物的溶解释放,单位质量煤矸石溶解释放的污染物量越多,煤矸石中污染物的溶解释放规律受扩散控制;在同一固液比条件下,各污染物浓度变化与浸泡时间成对数曲线关系,即Ct=a bLogt。 相似文献
128.
针对铁-法煤田因采矿引发的地面沉降和地面塌陷两种地质灾害进行研究,认为采法、采区、采深、采高、顶板管理是影响沉陷灾害的直接因素;岩性、构造、水文地质条件及矿坑降水是影响沉陷灾害的间接因素。其中矿坑降水是不可忽视的重要因素。根据地下水降深、降落漏斗影响半径、岩土工程地质性质,计算降水引发的地表沉降值、水平移动、倾斜、曲率现状值。现有的地表变形曲线为采矿和降水引发地表变形曲线的叠加。可得出可靠的灾害危险性分区。 相似文献
129.
山东兖州东滩矿3#煤层自燃临界氧浓度指标研究 总被引:1,自引:0,他引:1
文章采用煤自燃的模拟试验装置,对兖州东滩矿3#煤层煤样在不同的氧浓度条件下(分别为21%、13%、10%、7%和5%)进行了煤样自燃过程的实验研究,分别得到了两煤样的一氧化碳浓度与煤温关系曲线、自燃氧化中氧浓度的变化曲线、不同氧浓度下的热力学特性曲线、煤样CO增率与煤温关系曲线和煤样耗氧速度与煤温关系曲线。经过分析研究得出,不同温度下反应生成的标志气体成分不同,以一氧化碳、乙烯和乙炔作为标志气体比较合适,能准确反映出煤的不同自燃阶段。对数据分析对比研究,得出东滩煤矿3#煤层的自燃临界氧浓度指标为10%。 相似文献
130.
酸性矿山废水处理技术及其进展 总被引:2,自引:0,他引:2
向武 《地质灾害与环境保护》1998,9(2):38-40
论述酸性矿山废水(AMD)的处理方法及几种较新的AMD处理技术。阐明酸性矿山废水的危害及传统的碱中和法和不足,指责发展新型AMD处理技术是解决酸性矿山废水对环境危害的重要环节。 相似文献