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991.
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Salman Sharifazari Mahmood Sadat-Noori Habibeh Rahimi Danial Khojasteh William Glamore 《水科学与水工程》2021,14(4):260-268
Optimizing reservoir operation is critical to ongoing sustainable water resources management. However, different stakeholders in reservoir management often have different interests and resource competition may provoke conflicts. Resource competition warrants the use of bargaining solution approaches to develop an optimal operational scheme. In this study, the Nash bargaining solution method was used to formulate an objective function for water allocation in a reservoir. Additionally, the genetic and ant colony optimization algorithms were used to achieve optimal solutions of the objective function. The Mahabad Dam in West Azerbaijan, Iran, was used as a case study site due to its complex water allocation requirements for multiple stakeholders, including agricultural, domestic, industrial, and environmental sectors. The relative weights of different sectors in the objective function were determined using a discrete kernel based on the priorities stipulated by the government (the Lake Urmia National Restoration Program). According to the policies for the agricultural sector, water allocation optimization for different sectors was carried out using three scenarios: (1) the current situation, (2) optimization of the cultivation pattern, and (3) changes to the irrigation system. The results showed that the objective function and the Nash bargaining solution method led to a water utility for all stakeholders of 98%. Furthermore, the two optimization algorithms were used to achieve the global optimal solution of the objective function, and reduced the failure of the domestic sector by 10% while meeting the required objective in water-limited periods. As the conflicts among stakeholders may become more common with a changing climate and an increase in water demand, these results have implications for reservoir operation and associated policies. 相似文献
994.
白洋淀水温变化规律研究 总被引:1,自引:1,他引:0
依据白洋淀数字化地形图,结合白洋淀地区年平均气温变化数据,对白洋淀的水温变化规律进行了数值模拟。模拟表明:在水生生物最佳生长水位时(以大沽高程8.0m为例),(1)白洋淀水温在水平方向上(表层以下)分布具有差异,8月前,浅水区水温较高,深水区水温较低。8月后,水平温度分布不再有差异。(2)水温垂向分布呈现分层现象。7月下旬前,垂向分层由不规则逐渐向具有规则性发展,深水区分层数稍多于浅水区分层,7月底8月初,分层极具规则性。8月中旬,垂向水温达到一致,没有分层现象,9月后,又出现新的分层.(3)表底温差在8月初一直存在,浅水区表底温差小于深水区的。8月中旬,表底温差消失,9月初重新出现。(4)从动力学、热力学的角度研究了白洋淀的水温变化规律。 相似文献
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997.
Bruce B. Hicks 《Journal of Great Lakes research》2007,33(1):114-121
Early work indicated that wet deposition of radioactive fallout to the water surface of a lake greatly exceeded dry, when calculated as annual averages. To test whether this result also applies to the deposition rates of soluble trace gases from the lower atmosphere, data collected at land sites near Lake Champlain have been used to estimate deposition rates to the lake itself, using an analysis of the wind speed-up factor as an intermediate step. The contribution of dry deposition of the major nitrogen and sulfur chemical species is estimated to have been less than 20% of the total atmospheric deposition. However, this result must not be extrapolated to the watershed in which Lake Champlain resides, since evidence obtained elsewhere indicates that the dry deposition contribution over the entire watershed will likely be similar to the wet. The analysis indicates that for the period from 1992 to 1997 the annual total deposition rates of oxidized nitrogen and sulfur ranged from 300 to 500 tonnes per year and 600 to 1,100 tonnes per year, respectively. 相似文献
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999.
Miki Sudo Takuya Okubo Takao Kunimatsu Senichi Ebise Masahisa Nakamura Ryoichi Kaneki 《Lakes & Reservoirs: Research and Management》2002,7(4):301-308
The annual pesticide inputs and outputs crossing the boundary of Lake Biwa were estimated. The inputs were calculated from continuous observations in four rivers flowing into Akani Bay, and from simultaneous observations in 65 influent rivers. The annual losses of pesticide from the watershed to Lake Biwa were 1.7% for esprocarb, 4.8% for mefenacet, 2.3% for thiobencarb, 3.7% for molinate, 9.4% for simetryn and 13.0% for isoprothiolane. The outputs from the lake were estimated from weekly observations in the Seta River. The loss of pesticides discharged downstream through the Seta River, compared with the amount applied, were estimated to be 0.9% for esprocarb, 3.2% for mefenacet, 0.5% for thiobencarb, 1.3% for molinate, 10.0% for simetryn and 5.7% for isoprothiolane. Pesticide outputs generally decreased to 30–80% of the input amounts, although simetryn was retained in the lake without substantial elimination. 相似文献
1000.
羊湖电站引水隧洞长5883.103m,内径2.5m,海拔高程4400m以上,是目前世界上海拔最高的引水隧洞。具有海拔高、断面小、隧洞长、施工难度大等特点。本文就羊湖电站引水隧洞的施工组织与管理作一简要介绍,为在高寒缺氧地区进行隧洞施工提供一些可借鉴的经验。 相似文献