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271.
272.
The CBELSA/TAPS Collaboration M. Nanova S. Friedrich V. Metag E. Ya. Paryev F. N. Afzal D. Bayadilov B. Bantes R. Beck M. Becker S. Böse K. -T. Brinkmann V. Crede P. Drexler H. Eberhardt D. Elsner F. Frommberger Ch. Funke M. Gottschall M. Grüner E. Gutz Ch. Hammann J. Hannappel J. Hartmann W. Hillert Ph. Hoffmeister Ch. Honisch T. Jude D. Kaiser F. Kalischewski I. Keshelashvili F. Klein K. Koop B. Krusche M. Lang K. Makonyi F. Messi J. Müller J. Müllers D. Piontek T. Rostomyan D. Schaab Ch. Schmidt H. Schmieden R. Schmitz T. Seifen V. Sokhoyan C. Sowa K. Spieker A. Thiel U. Thoma T. Triffterer M. Urban H. van Pee D. Walther Ch. Wendel D. Werthmüller U. Wiedner A. Wilson L. Witthauer Y. Wunderlich H. -G. Zaunick 《The European Physical Journal A - Hadrons and Nuclei》2018,54(10):182
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Prof. Dr.-Ing. G. Brinkmann 《Archive of Applied Mechanics (Ingenieur Archiv)》1978,47(4):197-206
Übersicht Schalenformen können mit Hilfe sehr verschiedener Methoden gefunden werden. In der Arbeit werden mathematische Ansätze und Ergebnisse für die Simulation von experimentellen Formfindungsmethoden flacher Schalen vorgestellt. Das Tragverhalten und die Stabilität solcher optimierten Schalen wird unter Berücksichtigung von Last- und Formimperfektionen berechnet.
Herrn Prof. Dr.-Ing. F. W. Bornscheuer zu seinem 60. Geburtstag. 相似文献
Summary The shape of shells can be determined by several methods. In the paper the mathematical background for the experimental formfinding methods for shallow shells is investigated. The load bearing behaviour and stability of these optimized shells and their stability under consideration of load- and form-imperfection is analysed.
Herrn Prof. Dr.-Ing. F. W. Bornscheuer zu seinem 60. Geburtstag. 相似文献
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277.
Christian Melzer Martin Brinkmann Victor V Krasnikov Georges Hadziioannou 《Chemphyschem》2005,6(11):2376-2382
We investigated various thin-film morphologies of vacuum-deposited highly luminescent 2,5-di-n-octyloxy-1,4-bis[4'-(styryl)styryl]benzene (Ooct-OPV5) in a typical light-emitting-diode device structure. Important modifications in the thin-film morphology and structure were obtained by changing the substrate temperature in the range 23-90 degrees C. Structural analysis by X-ray and electron diffraction provided clear evidence for polymorphism in evaporated thin films of Ooct-OPV5. Concomitantly, the hole mobility in the corresponding devices was determined by transient electroluminescence measurements. We demonstrate that the substrate temperature T(sub) is a key parameter that controls the hole mobility of the devices. Increasing T(sub) between 23 and 84 degrees C results in a progressive increase of the zero-field hole mobility from 10(-6) to 10(-4) cm(2) V(-1) s(-1). The increase in hole mobility is correlated to the average grain size in the thin films. In addition, we give evidence for the existence of a peculiar growth mode in the bulk crystal structure of Ooct-OPV5, whereby the (a,b) and (b,c) planes can grow in a homoepitaxial manner. 相似文献
278.
On the Strongest Form of a Theorem of Whitney for Hamiltonian Cycles in Plane Triangulations
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In this article, we investigate hamiltonian cycles in plane triangulations. The aim of the article is to find the strongest possible form of Whitney's theorem about hamiltonian triangulations in terms of the decomposition tree defined by separating triangles. We will decide on the existence of nonhamiltonian triangulations with given decomposition trees for all trees except trees with exactly one vertex with degree and all other degrees at most 3. For these cases, we show that it is sufficient to decide on the existence of nonhamiltonian triangulations with decomposition tree K1, 4 or K1, 5. We also give computational results on the size of a possible minimal nonhamiltonian triangulation with these decomposition trees. 相似文献
279.
In an extended introduction, key aspects of resonance Raman spectroscopy (RRS) such as enhanced sensitivity and selectivity are briefly discussed in comparison with normal RS. The analytical potential is outlined. Then achievements in different fields of research are highlighted in four sections, with emphasis on recent breakthroughs: (1) The use of visible RRS for analyzing carotenoids in biological matrices, for pigments and dyes as dealt with in art and forensics, and for characterizing carbon nanotubes. (2) The use of RRS in the deep UV (excitation below 260 nm) in the bioanalytical and life sciences fields, including nucleic acids, proteins and protein-drug interactions. Metalloproteins can be studied by visible RRS in resonance with their chromophoric absorption. (3) Progress in theoretical calculations of RRS excitation profiles and enhancement factors, which ultimately might facilitate analytical RRS. (4) Instrumental and methodological achievements including fiber-optic UV-RRS, coupling of RRS to liquid chromatography and capillary electrophoresis. Sensitivities can approach the single-molecule level with surface-enhanced RRS or tip-enhanced RRS. Last but not least, promising fluorescence background rejection techniques based on time-gated detection will be presented. This review ends with a concluding section on future expectations for RRS, in particular its potential as an analytical technique. 相似文献
280.
Andrej Oriňák Ivan Talian Evtim V. Efremov Freek Ariese Renata Oriáaková 《Chromatographia》2008,67(3-4):315-319
Hyphenation of thin layer chromatography (TLC) with surface-based spectral methods requires a homogeneous surface for direct
and quantitative analysis on the chromatographic plate after separation. Since most chromatographic materials do not produce
strong background signals in Raman spectroscopy (RS) or surface-enhanced RS (SERS), we tested the suitability of two different
chromatographic substrates and one interface for coupling SERS with TLC. This was carried out by using a chromatographic thin
layer, specially produced for RS measurements, and a monolithic silica thin layer. A typical TLC plate with a modified aluminium
backplate foil on one side was used as an interface. Three biologically active diterpenes, namely gibberellic acid (GA), abietic
acid (AA) and kaurenoic acid (KA), were used as test analytes. Stock solutions were applied directly onto the surface, followed
by the addition of silver colloid and measurements were taken by SERS. The strongest signal (excitation at 514.5 nm) was obtained
for GA using a Raman treated thin layer where the enhancement factor value was determined to be 102. Several fundamental Raman bands for GA were found at 1622, 1593, 1570, 1542, 1366 and 1236 cm−1. When the monolithic silica layer was used, no useful SERS signals were observed. The SERS spectra on modified aluminium
backplate for AA and GA were quite similar and no SERS spectrum was obtained for KA. Future research will be concerned towards
the use of nanostructured surfaces for SERS analysis.
An erratum to this article can be found at 相似文献