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131.
J. E. S. Farjallat J. A. Nery de Oliveira 《Bulletin of Engineering Geology and the Environment》1972,6(1):83-96
The weatherability of the basalts in the Capivara Dam site, Rio Paranapanema, São Paulo State, Brazil, has been studied by means of saturation-drying tests. A great number of samples have disaggre — gated intensively with production of fines. The behavior of these rocks is related to their petrography, especially to their content in expansive clay minerals. These studies were performed in order to obtain data for the utilization of this material as rock fill, including ripraps. 相似文献
132.
文章立足于中英街部分建筑的改造,分析了特殊历史地位和特殊地域的旧街道改造时所面临的问题和挑战. 相似文献
133.
To assess the dose of UV light needed to achieve specified levels of Giardia spp. cysts and Cryptosporidium spp. oocysts inactivation in drinking water, a Bayesian meta-analysis is used to analyze experimental data from several studies. Of the 20 studies identified by an extensive data collection effort, 14 (five reported experiments on Giardia and nine on Cryptosporidium) were selected for analysis based on a set of criteria. A substantial amount of the log inactivation data are reported as greater than a given inactivation level (i.e., censored data). The Bayesian hierarchical modeling approach used in this study not only properly addresses the common concerns in a meta-analysis but also provides a robust method for incorporating censored data. Different statistical models will result in different estimates of the UV doses needed to achieve a specific inactivation level. The Bayesian approach allows us to present the uncertainty in terms of risk, which is better suited for supporting US EPA in developing regulations. 相似文献
134.
随着城市建设的大规模开展,大型低洼小区排水成为经常遇到的难题。该文通过工程实例,分析如何利用挡水设施、地面径流控制措施、现场外径流控制措施等方法,解决大型低洼小区雨水排水问题,以期用最低的投资来获取最大的排水安全性。 相似文献
135.
Trace element analysis of Cretan wines and wine products 总被引:2,自引:0,他引:2
Galani-Nikolakaki S Kallithrakas-Kontos N Katsanos AA 《The Science of the total environment》2002,285(1-3):155-163
The object of this research is to investigate the ways and the degree of contamination of Cretan grapes from the area of Chania and their alcoholic products, with the elements aluminium, arsenic, cadmium, copper, chromium, iron, lead, manganese, nickel and zinc. Fifteen samples of grapes were collected and used for the production of experimental wines from rinsed and unrinsed grapes. A microwave furnace was used for the digestion and dissolution of the experimental wines, the precipitates that originated in these wines, as well as the wines of the corresponding producers. The analyses of all mentioned samples as well as 34 local alcoholic distillates were performed using total reflection X-ray fluorescence and graphite furnace atomic absorption spectrometry. The concentrations for all the elements that were determined were almost in all cases, well below the maximum permissible levels by the Greek and the European Union legislation. 相似文献
136.
Soil salinity of urban turf areas irrigated with saline water: I. Spatial variability 总被引:2,自引:0,他引:2
S. Miyamoto Arturo Chacon Manwar Hossain Ignacio Martinez 《Landscape and urban planning》2005,71(2-4):233-241
With increasing use of saline water for irrigating urban landscapes, soil salinization is becoming a concern. This study examined spatial variation in soil salinity over the length of selected fairways at five golf courses, and of large turf areas at two public parks located in west Texas and southern New Mexico. Salinity of water used for irrigation ranged from 680 to 2700 mg L−1, and the sites consisted mostly of Aridisols (upland soils) or Entisols (alluvial soils). Soil salinity distribution at sites consisting of deep Aridisols was spatially independent with the coefficient of variability (CV) ranging from 24 to 42%. The sites consisting of shallow Aridisols over a calcic horizon had erratic and random soil salinity distributions with an average CV of 37%. Since soil salinity distributions in Aridisols and Alfisols appeared to be spatially independent within the distance of fairways, soil sampling adequacy can be determined by the conventional probability statistics. However, salinity distributions at Entisols sites were spatially dependant to a length of 100 m or more. In addition, the clayey Entisols used for public parks had high levels of salt accumulation (>10 dS m−1 in the saturation extract) with the CV exceeding 60%. When salinity readings were stratified by soil type distribution, the CV was reduced to 28% on the average. The number of samples required to obtain the mean salinity over a typical length of fairways (250–300 m) within a deviate range of 20% averaged 6 in deep sandy Aridisols and Alfisols, and 13 each in other cases, provided that sampling of Entisols is made based on soil type distributions. These sampling requirements are greater than those for field soil moisture or saturation water contents. The spacing to collect the required number of samples over the prevailing length of fairways was between 23 and 38 m. Soil sampling for salinity appraisal is most problematic in Entisols, but can be made simple if a detailed soil map is available. In Aridisols containing a calcic horizon, it is probable to have saline spots over poorly permeable caliche. 相似文献
137.
G. S. Xeidakis I. S. Samaras 《Bulletin of Engineering Geology and the Environment》1996,53(1):121-129
The use of marble in Architecture began on the 7th century B.C. and continued to be used without stop untill today. Greece and especially the East Macedonia region is an extremely privileged area on marble deposits both in quantities and qualities and colours. In the present work the main physical and engineering properties of some varieties of greek marbles are given and a comparison with the international standards is made. The experimental material (marbles) was from East Macedonia, Argolida-Arcadia and Magnessia, three of the biggest marble deposit areas in Greece. From the results obtained, it is concluded that the marbles examined satisfy all the international standard codes and thus they can be used as building stones and decoration materials. 相似文献
138.
1 后发工业化国家可通过政府引导打破贫穷的怪圈 资本主义世界几个世纪的发展历史显示,资本主义体系中的穷国一直循环着"国家贫穷-低收入、低积累-购买力弱、市场空间狭窄-单一项目投资难以回收-缺少投资-生产力低下-仍然贫穷"的怪圈. 相似文献
139.
140.