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91.
The problem of separating single-wall carbon nanotubes (CNTs) by diameter and/or chirality is one of the greatest impediments toward the widespread application of these promising materials in nanoelectronics. In this paper, we describe a novel physical-chemical method for diameter-selective CNT separation that is both simple and effective and that allows up-scaling to large volumes at modest cost. Separation is based on size-selective noncovalent matching of an appropriate anchor molecule to the wall of the CNT, enabling suspension of the CNTs in solvents in which they would otherwise not be soluble. We demonstrate size-selective separation in the 1-2 nm diameter range using easily synthesized oligo-acene adducts as a diameter-selective molecular anchor. CNT field effect transistors fabricated from diameter-selected CNTs show markedly improved electrical properties as compared to nonselected CNTs. 相似文献
92.
Rikke Skovgaard Nielsen 《Housing Studies》2016,31(6):631-650
The purpose of this paper is to test the evidence for spatial assimilation and straight-line assimilation in the transition of leaving home in Denmark. Based on data from the extensive Danish registers, the paper analyses the home-leaving patterns of Danes, Turkish immigrants, Turkish descendants and Somali immigrants. Two main findings emerged. First, while spatial segregation patterns of home-leavers were clear, inter-generational mobility did take place, supporting the notion of straight-line assimilation. Second, inter-generational effects were identified. While there was no indication that parental socio-economic situation affected the spatial segregation of home-leavers, substantial effects were found for the share of ethnic minorities in the parental neighbourhood: the higher the share of ethnic minorities, the higher the hazard for moving to an ethnic neighbourhood and the lower the hazard for moving to a non-ethnic neighbourhood. Similarity in the patterns of natives and the ethnic minority groups indicates that the processes taking place might be about more than assimilation between generations. 相似文献
93.
94.
In this paper we aim to give insight to how manufacturing strategies, represented by manufacturing paradigms are linked to different approaches to knowledge. Strategies are closely related to the development of core competence and how to deal with knowledge in general. In this paper we focus on how the different manufacturing strategies represent different challenges when it comes to knowledge creation and knowledge transfer. Our discussion has references to suppliers in the automotive industry, represented by a Scandinavian case. In this case the focus is on lean principles, which in contrast to mass manufacturing, represents attention to the synthetic knowledge base and tacit knowledge. Mass manufacturing, which is also still relevant in the automotive industry, is more centralised in its approach to knowledge and is focusing more on the analytical knowledge base and explicit knowledge. Knowledge should be a central part of companies’ strategies, also functional such as within manufacturing, and should cover issues such as: what is crucial knowledge, how do we create it, and how to transfer it to meet our overall company goals? 相似文献
95.
Stolzenbach S Therkildsen M Oksbjerg N Lazarotti R Ertbjerg P Lametsch R Byrne DV 《Meat science》2009,81(1):163-170
The effects of restrictive feeding strategies aimed at promoting a compensatory growth response were investigated with respect to tenderness improvement in pork M. longissimus thoracis. Compensatory growth response is defined by increased weight in pigs fed ad libitum after a period with restricted feeding compared to pigs fed ad libitum the entire fattening period. Specifically, the aim was to study the sensory textural characteristics after female and entire male pigs have been exposed to restrictions in either energy, protein or both in specific growth periods. It was found that textural differences were caused by feeding strategies and not related to variation in intramuscular fat, which did not vary significantly between genders. The female pigs demonstrated compensatory growth response and the texture was significantly (P<0.001) improved by low dietary level of energy from day 50 to 90 and normal dietary level of protein during the entire feeding period. For the entire male pigs, low level of protein in the late feeding period significantly (P<0.05) improved the texture. Also, low level of protein and normal level of energy in the early feeding period resulted in improved tenderness. However, these texture improvements were deemed not to be an effect of compensatory growth since the entire male pigs did not compensate for the feeding restriction in the early feeding period. The tenderness enhancement for the entire male pigs compromised the production results in terms of 7-15% lower carcass weight. 相似文献
96.
97.
P. Martínez-Santos H.J. Henriksen P. Zorrilla P.E. Martínez-Alfaro 《Environmental Modelling & Software》2010,25(11):1439-1449
Participatory methods provide an increasingly accepted path to integrated assessment. This paper reflects on the role of two participatory modelling initiatives implemented in a highly conflictive setting: the Mancha Occidental aquifer, Spain. The methodologies are described within the context of the case study, examining their potential relevance to integrated assessment from a conceptual standpoint. The strengths and weaknesses of each approach are analysed in absolute and relative terms, attending to the different stages of the modelling process. The focus then shifts to explore the implications of this work within the context of participatory integrated assessment and scenario analysis. This serves the purpose of establishing the reasons why the tools have been useful in the eyes of stakeholders, and how the case-specific findings of this project may be relevant to other settings. 相似文献
98.
Henriksen L 《Tobacco control》2012,21(2):147-153
Evidence of the causal role of marketing in the tobacco epidemic and the advent of the WHO Framework Convention on Tobacco Control have inspired more than half the countries in the world to ban some forms of tobacco marketing. This paper briefly describes the ways in which cigarette marketing is restricted and the tobacco industry's efforts to subvert restrictions. It reviews what is known about the impact of marketing regulations on smoking by adults and adolescents. It also addresses what little is known about the impact of marketing bans in relation to concurrent population-level interventions, such as price controls, anti-tobacco media campaigns and smoke-free laws. Point of sale is the least regulated channel and research is needed to address the immediate and long-term consequences of policies to ban retail advertising and pack displays. Comprehensive marketing restrictions require a global ban on all forms of promotion, elimination of packaging and price as marketing tools, and limitations on the quantity, type and location of tobacco retailers. 相似文献
99.
The objective of the study was to evaluate a new pathogen inactivation concept that combines application of pressurized steam simultaneously with high-power ultrasound through a series of nozzles. On skin and meat surfaces of pork jowl samples, counts of total viable bacteria were reduced by 1.1 log CFU/cm(2) after treatment for 1 s and by 3.3 log CFU/cm(2) after treatment for 4 s. The mean reduction of 1.7 to 3.3 log CFU/cm(2) on the skin surface was significantly higher than the reduction of 1.1 to 2.5 log CFU/cm(2) on the meat surface. The inactivation of Salmonella Typhimurium, Salmonella Derby, Salmonella Infantis, Yersinia enterocolitica, and a nonpathogenic Escherichia coli was studied on inoculated samples that were treated for 0.5 to 2.0 s. With one exception, no significant differences in reduction were observed among the bacterial types. After treatment for 0.5 s, the 0.9-to 1.5-log reductions of E. coli were significantly higher than the 0.4- to 1.1-log reductions for Salmonella and Y. enterocolitica. Overall, reductions increased by increasing treatment time; reductions were 0.4 to 1.5 log CFU/cm(2) after treatment for 0.5 s and 2.0 to 3.6 log CFU/cm(2) after treatment for 2 s. Reductions on the skin (1 to 3.6 log CFU/cm(2)) were significantly higher than reductions on the meat surface (1 to 2.5 log CFU/cm(2)). The reduced effect on the meat surface may be explained by greater protection of bacteria in deep structures at the muscle surface. No significant difference in reduction was observed between samples inoculated with 10(4) CFU/cm(2) and those inoculated with 10(7) CFU/cm(2), and cold storage of samples for 24 h at 5°C after steam-ultrasound treatment did not lead to changes in recovery of bacteria. 相似文献
100.
Xin He Simon Stisen Marianne B. Wiese Hans Jørgen Henriksen 《Water Resources Management》2016,30(5):1785-1802
Increasing attention on extreme hydrological events has created considerable demand for real-time information on surface water, groundwater and the unsaturated zone. In the present study, we describe how to convert a national water resources model (DK-model) covering the entire freshwater cycle in Denmark to real-time application. We have engaged stakeholders in the process of designing a hydrological real-time system. The participatory approach has been supported by a web-based questionnaire survey and a participatory workshop. A system prototype presented to the stakeholders simulates groundwater levels, streamflow and water content in the root zone with a lead time of 48 h. The active engagement of stakeholders has provided very valuable insights and feedbacks regarding how model and data should be combined in a real-time to best supporting water resources management. 相似文献