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周富春 《土木与环境工程学报》2006,28(5):27-29
山区公路工程由于线长、工程量大,施工期可能引起比较严重的水土流失。在编制公路工程水土保持方案时,需要对水土流失量进行预测。公路沿线原地貌水土流失量及新增水土流失量之和即为全部的水土流失量。公路沿线原地貌水土流失量可以采用平均侵蚀模数法及通用土壤流失方程式进行预测,新增水土流失量由扰动地表和工程弃堆渣引起的水土流失量组成。最后,通过具体的工程,对山区公路工程建建设期水土流失量的预测模式进行了实证。 相似文献
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介绍了协整分析理论,结合第二松花江流域上下游的年径流量,阐述了单位根检验、协整检验、误差修正模型的理论与分析方法.采用白山站和丰满站1933~1998年的年径流量资料,用协整分析的方法建立模型,对丰满站1989~1998年的年径流量进行预测研究,研究结果表明基于协整与误差修正模型进行预测是有效的. 相似文献
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王健 《有色冶金设计与研究》2006,27(2):21-25,32
深圳河湾污水截排工程投资超过人民币5亿元。工程方案坚持以科学的发展观为指导,将节水与防污相结合,将发展循环经济作为方案研究的出发点与落脚点,对深圳河湾流域的污水处理尾水排海、污水资源化、水体生态修复等作出了长远规划。 相似文献
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Modification of rainfall-runoff processes by urban infrastructure and anthropogenic activities impacts receiving waters and the surrounding terrestrial environment. Infiltration–exfiltration systems such as a partial exfiltration reactor (PER) when loaded by transient sheet flow have the potential to attenuate the impact of both the quantity and quality of urban runoff. These in situ systems are subject to highly variable water quality and quantity while functioning under variably saturated flow conditions. To improve the understanding of field-scale PER performance as a rainfall-runoff unit operation and process, a two-dimensional (2D) numerical model was used to simulate the effluent hydrograph and water content profiles under transient hydraulic loadings. Richard’s equation was applied in the 2D model using parameters estimated from laboratory experiments and hydrographs measured for an in situ PER. The temporal dynamics of the water content illustrated the ability of the PER to lower peak flow, redistribute volume, and attenuate temporal aspects of the inflow hydrograph. Results demonstrated the role of the PER to attenuate runoff water quantity, while also providing water quality improvements, as illustrated for suspended solids and dissolved Cu. Simulation of historical events for different surrounding soils illustrated the critical role of surrounding soil conditions on PER performance. While the PER demonstrated water quantity attenuation benefits for design storms (1, 2, 5?year return periods), results also illustrate how a given PER design for clayey soils conditions can be limiting for intense events. Evaporation was a dominant mechanism for the drying process in the PER upper layer; with a residual moisture content in the porous pavement layer achieved in less than 2?days in summer for Cincinnati, Ohio. 相似文献
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Pollution Buildup on Road Surfaces 总被引:1,自引:0,他引:1
Samples of sediment found on an urban road in Aberdeen (Scotland) were collected by washing designated surfaces. This method, called the “wet” method, was capable of collecting sediment of the smallest particle size range that is normally left behind by traditional sampling techniques using dry vacuuming. Over 17 months (mainly on a weekly basis), 66 samples were collected and analyzed for sediment loading, particle size distribution, concentration of heavy metals (Zn, Cu, Pb, Cd) in four sediment size fractions, and several dissolved pollutants in the effluent collected from washing (NO3?,?SO42?,?PO43?,?Cl?,?F?,?NH4+, total organic carbon, total carbon). Standard statistical methods, including multiple regressions, were used to determine relationships amongst different sediment characteristics. It was found that sediment loading, as well as concentrations of Cl? and SO42?, were highest in the winter months, especially when snow was present on the road surface. It was observed that 66% of total road sediment loading was found within a 0.5 m strip next to the curb. The average sediment particle sizes found were smaller than those previously recorded in the literature. As expected, the concentrations of heavy metals were highest in the smallest particle size fraction analyzed (<63?μm), and this occurred during the summer months when less sediment was available on the street surface. The antecedent dry weather period had a very weak and negative influence on the loading rate of the smallest particle size fraction next to the curb. 相似文献
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基于多尺度分析理论,运用Mallat算法和Daubeclfies小波,把时间序列分解为比原始序列更单一的细节和慨貌部分,并利用AR(P)模型能反映时间序列中邻近时刻间联系的特性,对序列分解后的部分进行拟合与预测,然后再由多尺度分析中的重构方法进行序列重构,由此建立耦合的预测模型。通过黄河青铜峡270多年(1724~1997)年径流时间序列的建模及验证,表明拟建的耦合模型与传统单一模型的预测精度相比,由50%提高到90%,可用于实际需要。 相似文献
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