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51.
Alexander Alldridge Joachim Hilgert Tilmann Wurzbacher 《Mathematische Zeitschrift》2014,278(1-2):441-492
We introduce a wide category of superspaces, called locally finitely generated, which properly includes supermanifolds, but enjoys much stronger permanence properties, as are prompted by applications. Namely, it is closed under taking finite fibre products (i.e. is finitely complete) and thickenings by spectra of Weil superalgebras. Nevertheless, in this category, morphisms with values in a supermanifold are still given in terms of coordinates. This framework gives a natural notion of relative supermanifolds over a locally finitely generated base. Moreover, the existence of inner homs, whose source is the spectrum of a Weil superalgebra, is established; they are generalisations of the Weil functors defined for smooth manifolds. 相似文献
52.
An der Lan L Bartl P Leidlmair C Schöbel H Jochum R Denifl S Märk TD Ellis AM Scheier P 《The Journal of chemical physics》2011,135(4):044309
The submersion of sodium clusters beyond a critical size in helium nanodroplets, which has recently been predicted on theoretical grounds, is demonstrated for the first time. Confirmation of a clear transition from a surface location, which occurs for alkali atoms and small clusters, to full immersion for larger clusters, is provided by identifying the threshold electron energy required to initiate Na(n) cluster ionization. On the basis of these measurements, a lower limit for the cluster size required for submersion, n ≥ 21, has been determined. This finding is consistent with the recent theoretical prediction. 相似文献
53.
Compactly Supported Correlation Functions 总被引:2,自引:0,他引:2
Tilmann Gneiting 《Journal of multivariate analysis》2002,83(2):493
This article proposes compactly supported correlation functions, which parameterize the smoothness of the associated stationary and isotropic random field. The constructions are straightforward, and compact support is relevant for various ends: computationally efficient spatial prediction, fast and exact simulation, and appeal among practicioners. 相似文献
54.
Rainer Traber Ekehardt Vogelmann Siegfried Schreiner Tilmann Werner Horst E. A. Kramer† 《Photochemistry and photobiology》1981,33(1):41-48
Abstract— Quenching of the excited states of lumiflavin and 3-methyl-5-deazalumiflavin by methyl-and methoxy-substituted benzenes and naphthalenes in methanol was investigated. The observed difference in the reactivity of acid and neutral lumiflavin triplets is explained thermodynamically by applying the Michaelis cycle, as being due to the higher reduction potential of the acid triplet. In this connection the p K values of lumiflavin triplet (p K M = 6.5) and semiquinone (p K M = 11.3) have also been determined in methanol. The difference in the reactivity between the singlet and triplet states of lumiflavin is found to be greater as predicted by the difference in excitation energy. The reactivities of the excited states of flavin and 5-deazaflavin differ only slightly in contrast to the marked difference in the ground state reactivities of electron transfer reactions. This is explained in terms of the model of Rehm and Weller. The pH dependence of the electron transfer quenching of 5-deazaflavin triplet was investigated in water, yielding a triplet p K of 2.5. In contrast to the flavin, this triplet p K does not significantly differ from the p K of the 5-deazaflavin ground state. From this, different sites of protonation are deduced for the photoexcited triplet states of flavin and 5-deazaflavin. 相似文献
55.
Thana Maihom Ivan Sukuba Ratko Janev Kurt Becker Tilmann Märk Alexander Kaiser Jumras Limtrakul Jan Urban Pavel Mach Michael Probst 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2013,67(1):1-5
We report calculated electron impact ionization cross sections (EICSs) for beryllium (Be) and some of its hydrides from the ionization threshold to 1 keV using the Deutsch-Märk (DM) and the Binary-Encounter-Bethe (BEB) formalisms. The positions of the maxima of the DM and BEB cross sections are very close in each case while the DM cross section values at the maxima are consistently higher. Our calculations for Be are in qualitative agreement with results from earlier calculations (convergent close-coupling, R matrix, distorted-wave and plane-wave Born approximation) in the low energy region. For the various beryllium hydrides, we know of no other available data. The maximum cross section values for the various compounds range from 4.0 × 10?16 to 9.4 × 10?16 cm2 at energies of 44 to 56 eV for the DM cross sections and 3.0 × 10?16 to 5.4 × 10?16 cm2 at energies of 40.5 to 60 eV for the BEB cross sections. 相似文献
56.
57.
Wurzbacher T Döllinger M Schwarz R Hoppe U Eysholdt U Lohscheller J 《The Journal of the Acoustical Society of America》2008,123(4):2324-2334
A model-based approach is proposed to objectively measure and classify vocal fold vibrations by left-right asymmetries along the anterior-posterior direction, especially in the case of nonstationary phonation. For this purpose, vocal fold dynamics are recorded in real time with a digital high-speed camera during phonation of sustained vowels as well as pitch raises. The dynamics of a multimass model with time-dependent parameters are matched to vocal fold vibrations extracted at dorsal, medial, and ventral positions by an automatic optimization procedure. The block-based optimization accounts for nonstationary vibrations and compares the vocal fold and model dynamics by wavelet coefficients. The optimization is verified with synthetically generated data sets and is applied to 40 clinical high-speed recordings comprising normal and pathological voice subjects. The resulting model parameters allow an intuitive visual assessment of vocal fold instabilities within an asymmetry diagram and are applicable to an objective quantification of asymmetries. 相似文献
58.
59.
Inside Back Cover: A Detailed Analysis of the Morphology of Fibrils of Selectively Mutated Amyloid β (1–40) (ChemPhysChem 17/2016)
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60.
Back Cover: Divergent Coordination Chemistry: Parallel Synthesis of [2×2] Iron(II) Grid‐Complex Tauto‐Conformers (Angew. Chem. Int. Ed. 36/2016)
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