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31.
A failure mechanism of submarine landslides based on the phenomenon of shear band propagation has been investigated using
the energy balance approach. Dynamic analysis includes inertia effects in the sliding layer and viscous resistance of the
water, but ignores elastic and plastic wave propagation in the sliding layer. The resulting differential equation has been
solved numerically. Analytical approximation of this numerical solution provides a convenient basis for the parametric and
sensitivity studies. The solution allows assessing the velocity and acceleration of both the landslide and the shear band
at the moment when the slide fails due to the limiting equilibrium (i.e., the initial post-failure velocity). The effects
of the initial landslide velocity on the tsunami wave height are discussed and validated for a number of landslide examples. 相似文献
32.
Sorantin E Halmai C Erdöhelyi B Palágyi K Nyúl LG Ollé K Geiger B Lindbichler F Friedrich G Kiesler K 《IEEE transactions on medical imaging》2002,21(3):263-273
PURPOSE: Demonstration of a technique for three-dimensional (3-D) assessment of tracheal-stenoses, regarding site, length and degree, based on spiral computed tomography (S-CT). PATIENTS AND METHODS: S-CT scanning and automated segmentation of the laryngo-tracheal tract (LTT) was followed by the extraction of the LTT medial axis using a skeletonization algorithm. Orthogonal to the medial axis the LTT 3-D cross-sectional profile was computed and presented as line charts, where degree and length was obtained. Values for both parameters were compared between 36 patients and 18 normal controls separately. Accuracy and precision was derived from 17 phantom studies. RESULTS: Average degree and length of tracheal stenoses was found to be 60.5% and 4.32 cm in patients compared with minor caliber changes of 8.8% and 2.31 cm in normal controls (p < 0.0001). For the phantoms an excellent correlation between the true and computed 3-D cross-sectional profile was found (p < 0.005) and an accuracy for length and degree measurements of 2.14 mm and 2.53% respectively could be determined. The corresponding figures for the precision were found to be 0.92 mm and 2.56%. CONCLUSION: LTT 3-D cross-sectional profiles permit objective, accurate and precise assessment of LTT caliber changes. Minor LTT caliber changes can be observed even in normals and, in case of an otherwise normal S-CT study, can be regarded as artifacts. 相似文献
33.
Steinle ED Mitchell DT Wirtz M Lee SB Young VY Martin CR 《Analytical chemistry》2002,74(10):2416-2422
This paper describes synthetic micropore and nanotube membranes that mimic the function of a ligand-gated ion channel; that is, these membranes can be switched from an "off" state (no or low ion current through the membrane) to an "on" state (higher ion current) in response to the presence of a chemical stimulus. Ion channel mimics based on both microporous alumina and Au nanotube membranes were investigated. The off state was obtained by making the membranes hydrophobic by chemisorbing either a C18 silane (alumina membrane) or a C18 thiol (Au nanotube membrane). Water and electrolyte are forbidden from entering these very hydrophobic pores/nanotubes. The transition to the on state was induced by the partitioning of a hydrophobic ionic species (e.g., a drug or a surfactant) into the membrane. The membrane switches to the on state because at a sufficiently high concentration of this ionic analyte species, the pores/nanotubes flood with water and electrolyte. A pH-responsive membrane was also prepared by attaching a hydrophobic alkyl carboxylic acid silane to the alumina membrane. 相似文献
34.
G
2 interpolation and blending on surfaces 总被引:3,自引:0,他引:3
Erich Hartmann 《The Visual computer》1996,12(4):181-192
We introduce a method for curvature-continuous (G
2) interpolation of an arbitrary sequence of points on a surface (implicit or parametric) with prescribed tangent and geodesic curvature at every point. The method can also be used forG
2 blending of curves on surfaces. The interpolation/blending curve is the intersection curve of the given surface with a functional spline (implicit) surface. For the construction of blending curves, we derive the necessary formulas for the curvature of the surfaces. The intermediate results areG
2 interpolation/blending methods in IR2. 相似文献
35.
36.
Erich Kutzer 《Zeitschrift für Jagdwissenschaft》1969,15(4):172
Ohne Zusammenfassung 相似文献
37.
Helena Windemann Urs Müller und Erich Baumgartner 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1973,153(1):17-22
Zusammenfassung Die isoelektrische Fokussierung einer wasserlöslichen Proteinfraktion von Hart- und Weichweizen aus Teigwarenprodukten wird mit der bisher üblichen disk-elektrophoretischen Trennmethode verglichen. Die Elektrofokussierung liefert im Gegensatz zur Disk-Elektrophorese auch bei Anwesenheit von Ei-Proteinen sowie nach vorgängiger Hitzedenaturierung der Proteine zuverlässige und genaue Resultate. Im weiteren wird zur besseren Auftrennung und Charakterisierung der wasserlöslichen Proteinfraktion eine zweidimensionale Trennmethode (isoelektrische Fokussierung und anschließende Elektrophorese) beschrieben.
Isoelectric focusing and two-dimensional separation of watersoluble protein fraction of hard and soft wheat from macaroni
Summary The isoelectric focusing of water-soluble protein fraction of hard and soft wheat from macaroni are compared with the disc electrophoresic separation methods. Electrofocusing produced more trustworthy and exacter results in the presence of egg proteins as well for heat-denaturated proteins. Further is described a better separation and characterisation of a water-soluble protein fraction using a two-dimensional system involving isoelectric focusing in the first dimension followed by electrophoresis in the second.相似文献
38.
39.
Ulrich?ThielEmail author Holger?Brocks Ingo?Frommholz Andrea?Dirsch-Weigand Jürgen?Keiper Adelheit?Stein Erich J.?Neuhold 《International Journal on Digital Libraries》2004,4(1):8-12
In the COLLATE project, we aim to design and implement a Web-based collaboratory for archives, scientists, and end users working with digitized cultural material. Our example domain is the historic film documentation comprising digitized material about European films of the early 20th century. Designed as a content- and context-based knowledge working environment for distributed user groups, the COLLATE system supports both individual work and collaboration of domain experts who are analyzing, evaluating, indexing, and annotating material in the data repository. The system provides appropriate task-based interfaces for indexing and annotating. As a multifunctional means of in-depth analysis, annotations can be made individually but also collaboratively, for example in the form of annotation of annotations. Combining results from manual and automatic indexing procedures, elaborate content- and context-based information retrieval mechanisms can be applied. 相似文献
40.
Erich?StrohmaierEmail author Hans W.?Meuer 《Computing and Visualization in Science》2004,6(4):227-230
Since 1993 we compile and publish twice a year a list of the most powerful supercomputers in the world. In this article we analyze some major trends in High-Performance Computing (HPC) based on the quantitative data gathered over the years in this TOP500 project (see www.top500.org for a complete access to all data). We start with an overview of the project, including the motivation and rationale behind it. We present the results of the TOP500 project as of November 2003 focusing on the changes over time with respect to the performance levels, the overall dynamics in this market, the manufacturers active in this market-segment, the architectures, and technologies used for these systems, and the major centers using such systems. 相似文献