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31.
阐明了白庙矿矿井水文地质条件,重点介绍了各含水层、隔水层的情况、主要的地质构造及相互之间的联系,分析了矿井开采的突水可能性,为矿井水防治工作奠定了基础. 相似文献
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A new methodology is presented in thisarticle for computing the optimal operation of soilaquifer treatment systems. The mathematical problemis stated as a discrete-time optimal control problemto maximize infiltration subject to various physicaland operation constraints. The methodology is basedupon solving the discrete-time optimal control problemusing a successive approximation linear quadraticregulator interfaced with a simulator. Theunsaturated flow model HYDRUS is modified to simulatethe water content distribution, the infiltrationprocess, and the draining process. A penalty functionmethod is used to treat the bound constraints on thewater content and the cycle time. Sample problems aregiven to illustrate the capability of the model tosolve the optimal operation of soil aquifer treatment systems. 相似文献
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关于一种潜水井裸井slug数学模型的探讨及实证 总被引:1,自引:0,他引:1
利用slug试验测量渗透系数在国内外已有了比较成熟的发展,但是专门应用于潜水井裸井的slug数学模型却极少出现在各类文献中。通过注水高度对潜水含水层厚度的影响推导对潜水含水层完整井的slug数学模型,此模型与传统的Bouwer and Rice模型相比考虑了注水后潜水面水位的增加对渗透系数K的影响,并结合室内变水头渗透试验和前期抽水试验来验证在工程实例运用此模型算出的渗透系数的准确性。更多还原 相似文献
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Influence of Seepage Face Obliquity on Discharge of Groundwater and its Pollutant into Lake from A Typical Unconfined Aquifer 总被引:1,自引:0,他引:1
Lab experiment and mathematical simulation Modular three dimensional finite difference groundwater (MODFLOW) were performed in a soil tank to simulate the hydrogeochemical interaction between lake and typical unconfined aquifer. Results show that the velocity decreases exponentially with the transect distance on seepage face. The maximal velocity occurs at the top point of seepage face. The obliquity of seepage face has a great influence on the maximum and distribution of seepage velocity. With the increase of the obliquity of seepage face, the maximal velocity decreases quickly and the velocity distribution becomes much more even. Most of groundwater flow and pollutant flux discharges through a narrow portion near the top of seepage face. The flow and mass concentrated in the narrow portion increase with the decrease of the obliquity of seepage face. These will benefit to design a reasonable and economical scenario to manage lakeshore and to control the pollution of lake water near lakeshore. 相似文献
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Abstract The North China Plain (NCP) is one of China's most important social, economic, and agricultural regions. Currently, the Plain has 17,950 thousand ha of cultivated land, 71.1 percent of which is irrigated, consuming more than 70 percent of the total water supply. Increasing water demands associated with rapid urban and industrial development and expansion of irrigated land have led to overexploitation of both surface and the ratio of groundwater resources, particularly north of the Yellow River. In 1993, the ratio of groundwater exploitation to recharge in many parts of the NCP exceeded 1.0; in some areas, the ratio exceeded 1.5. Consequently, about 1.06 million ha of water-short irrigated areas in the NCP also have poor water quality. Persistent groundwater overexploitation in the northern parts of the NCP has resulted in water-level declines in both shallow and deep aquifers. According to data from 600 shallow groundwater observation wells in the Hebei Plain, the average depth to water increased from 7.23 m in 1983 to 11.52 m in 1993, indicating an average water-table decline of 0.425 m/year. Water table declines are not uniformly distributed throughout the area. Depletion rates are generally greatest beneath cities and intensively groundwater-irrigated areas. Water-table declines have also varied over time. With the continued decline of groundwater levels, large depression cones have formed both in unconfined and confined aquifers beneath the Hebei Plain. Groundwater depletion in the NCP has severely impacted the environment. Large tracts of land that overlie cones of depression have subsided, seawater has intruded into previously freshwater aquifers in coastal plains, and ground-water quality has deteriorated due to salinization, seawater intrusion, and untreated urban and industrial wastewater discharge. In order to balance groundwater exploitation with recharge, the major remedial measures suggested are to strengthen groundwater management, to raise water use efficiency, to adjust the water-consumed structure, and to increase water supply 相似文献
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对于含水层参数连续性问题,传统的参数分区法会带来较大的计算误差,且其计算过程也较为繁琐。本文提出了一种新算法——边界元插值法,即在区域内对含水层压力传导系数采用二维反距离加权插值法、边界元上采用一维线性插值法,推导出边界积分方程的解析解,从而在整个区域上达到参数的连续性和可微性。将该方法与传统的有限差分法和边界元分区法同时应用于华北平原衡水试验场。计算结果表明:边界元插值法的计算结果与观测值的拟合误差在±3%以内,其精确度要略高于传统的边界元分区法和有限差分法,且计算过程较为简单。边界元插值法基本能够有效地处理含水层参数的连续性问题。 相似文献
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为了探究石羊河流域地下咸水资源的利用方式,在西北干旱区的石羊河流域开展了咸水灌溉田间试验,通过测定土壤含水率和制种玉米产量指标,研究咸水灌溉对制种玉米耗水量、产量、水分利用效率和灌溉水分利用效率的影响.研究结果表明:在相同灌溉水量条件下,不同灌水矿化度对制种玉米的耗水量影响不明显;随着灌水矿化度的增加,制种玉米的产量逐渐降低,3 g/L的微咸水灌溉与淡水灌溉相比,减产幅度在20%以下,而9 g/L的高矿化度的咸水灌溉减产幅度在30%以上;水分利用效率和灌溉水分利用效率具有与产量类似的规律.因此,在研究区短时期采用3 g/L以下的微咸水进行灌溉,对制种玉米减产幅度、水分利用效率和灌溉水分利用效率的影响较小. 相似文献