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1.
Gadolinium iron garnet was obtained from two different precursors, homogenized in isopropyl alcohol and in an aqueous environment with a fixed pH. In the first case, it was a mixture of goethite (FeO(OH)) and gadolinium oxide (Gd2O3); in the second, a mixture of GdIP (GdFeO3) and α-Fe2O3. Conditions of homogenization in the aqueous environment were selected based on the zeta (ξ) potential measurements as the function of pH. DSC measurements of the output powder mixtures allowed the identification of the effects observed during the temperature rise. In the case of the material obtained from a mixture of goethite (FeO(OH)) and gadolinium oxide, with the increasing temperature, we observe three effects, the first of which corresponds to the phase transformation of goethite into α-Fe2O3, the second corresponds to the reaction of gadolinium iron perovskite (GdIP) formation, and the third to the reaction in which a gadolinium iron garnet (GdIG) is formed. However, in the case of heat treatment of the mixture of GdIP and α-Fe2O3, we only observe the effect responsible for a solid state reaction leading to the formation of gadolinium iron garnet. Dilatometric measurements allowed to determine the changes in linear dimensions at various stages of reaction sintering. The resulting materials were sintered at temperatures of 1200, 1300, and 1400 °C. In the case of the material obtained from a mixture of perovskite and iron (III) oxide, already at the temperature of 1300 °C, a density has been obtained at around 95% of the theoretical density, and the temperature of 1400 °C allowed achieving a density of 97% of the theoretical density. Whereas, for the material obtained from a mixture of goethite (FeO(OH)) and gadolinium oxide, a density above 95% of theoretical density was achieved only at 1400 °C. 相似文献
2.
Gabriela Ben-Melech Stan Kapil Dhaka Maytal Caspary Toroker 《Israel journal of chemistry》2020,60(8-9):888-896
Two-dimensional transistors are promising candidates for the next generation of nanoscale devices. Like the other alternatives, they also encounter problems such as instability under standard condition (STP), low channel mobility, small band gaps, and difficulty to integrate metal contacts. The latter poses a great challenge since metal/semiconductor interface significantly affects the transistor‘s performance. Some of these obstacles can be solved by using two-dimensional transition metal di-chalcogenides (TMDC) materials. In this study, we performed charge transport calculation based on density functional theory (DFT) followed by wave dynamics to evaluate the performance of six two-dimensional TMDC metal/semiconductor/metal systems. Each semiconductor monolayer was laterally connected, at both ends to metal contacts consisting of VS2 or FeS2 monolayers. We found that charge transport was more efficient in systems containing a CrS2 semiconductor monolayer compared to systems with MoS2 or WS2 as the semiconductor monolayer. The electronic characterization of the monolayer TMDC materials by DFT estimates well the trend in charge transport efficiency calculated using wave packet dynamics. 相似文献
3.
Mohammad Alrosan Thuan-Chew Tan Azhar Mat Easa Sana Gammoh Stan Kubow Muhammad H. Alu'datt 《International Journal of Food Science & Technology》2022,57(4):2039-2050
There has been a growing interest in plant proteins due to their beneficial health effects, low cost and variety of applications in food industries. The low solubility of lentil proteins (LPs) is one of the significant factors that limit their use in food applications. Quinoa proteins (QPs), which have high water solubility, were combined with LPs at pH 12 to generate LP-QP complexes to generate pH-based soluble protein compounds. The LP-QP complexes demonstrated a large surface charge with an increase solubilisation of the protein complexes by more than 85%, together with resistance to protein aggregation. The combination of LPs to QPs led to a significant increase (P < 0.05) in unique tertiary and secondary protein structures as determined by the protein–protein interaction (PPI) technique involving pH recycling. Interactions between LPs and QPs affected the surface morphology of the protein complexes formed. Electrostatic interactions, hydrophobic forces and hydrogen bonding were indicated to play key roles in the PPIs. The capacity of pH cycling to illustrate the above protein interactions shows that this is a robust approach for assessing the emulsion and foaming properties of food proteins. 相似文献
4.
Sport Stadia, Sporting Events and Urban Development: International Experience and the Ambitions of Durban 总被引:1,自引:0,他引:1
The paper considers the stadium construction and infrastructure projects underway for World Cup 2010. We ask whether and under
which conditions hosting such an event (along with the new facilities and infrastructural development required) will have
positive effects on urban development. By analysing the stadium project in Durban, the paper also presents evidence on whether
such positive effects may be enhanced by the attempt to create an image effect by seeking outstanding architectural quality
of the new stadia.
相似文献
Wolfgang MaennigEmail: |
5.
ABSTRACT The paper describes a new approach to the graphical analysis of cancer data. A Geographical Analysis Machine is built which simultaneously solves the problems of post hot: hypothesis testing, handling data errors, and the task of generating and evaluating hypotheses in an exploratory environment. The methodology is demonstrated by reanalyzing cancer data for Northern England in such a way that for the first time the complex universe of all geographical hypotheses is enumerated, evaluated, and all the significant cancer clusters displayed. 相似文献
6.
Elisabeth Lichtenberger A. Subbakrishniah Milton H. Grannatt rd Antoine S. Bailly Charles G. Schmidt Dougald A. MacFarlane Rudolf Andorka Ernesto Quintanilla L. B. Wallerstein Stan Openshaw Herman G. Berkman Kingsley E. Haynes W. W. Hall Jr. Richard B. Le Heron John E. Stapleford Alan Pearman Paul Soyke Thomas R. Beard Howard F. Newell Michael Dear Kenneth D. Lawrence Peter Mastenbroek Rolf B. Schmitt Sung Woong Hong A. A. Horner James M. Murray Donald W. Jones W. E. Mullendore 《The Annals of Regional Science》1977,11(3):129-183
7.
Stan Majoor 《Journal of Housing and the Built Environment》2006,21(1):15-32
The implementation of concepts of multiple land use seems to be relevant in the context of large-scale urban projects, which are now predominately monofunctional. However, current governance settings at these projects seem to be unreceptive to this new planning concept. Our in-depth case study of the South Axis project in Amsterdam embraces an actor-centred institutional perspective and seeks to understand how more receptive conditions for norm alignment between key actors can be attained. We reconstruct the introduction of quite radical concepts of multiple land use in this project, which started as an office-development proposal. The implementation was severely hampered by the fact that ambitions were formed in a rather introvert local government – business setting. Only in the last stage, with the adoption of a more extrovert mode of governance that included a variety of national government departments, were more receptive conditions for multiple land use created. 相似文献
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