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11.
N. F. Blagoveshchenskaya T. D. Borisova V. A. Kornienko A. S. Janzhura A. S. Kalishin T. R. Robinson T. K. Yeoman D. M. Wright L. J. Baddeley 《Radiophysics and Quantum Electronics》2008,51(11):847-857
We present the results of experimental studies of specific features in the behavior of small-scale artificial field-aligned
irregularities (AFAIs) and the DM component in the spectra of stimulated electromagnetic emission (SEE). Analysis of experimental
data shows that AFAIs in the polar ionosphere are generated under different background geophysical conditions (season, local
time, the presence of sporadic layers in the E region, etc.). It is shown that AFAIs can be excited not only in the F region, but also in “thick” sporadic E
s layers of the polar ionosphere. The AFAIs were observed in some cycles of heating when the HF heater frequency exceeded the
critical frequency by 0.3–0.5 MHz. Propagation paths of diagnostic HF radio waves scattered by AFAIs were modelled for geophysical
conditions prevailing during the SPEAR heating experiments. Two components, namely, a narrow-banded one with a Doppler-spectrum
width of up to 2 Hz and a broadband one observed in a band of up to 20 Hz, were found in the sporadic E
s layer during the AFAI excitation. Analysis of the SEE spectra shows that the behavior of the DM component in time is irregular,
which is possibly due to strong variations in the critical frequency of the F
2 layer from 3.5 to 4.6 MHz. An interesting feature observed in the SPEAR heating experiments is that the generation of the
DM component was similar to the excitation of AFAIs when the heater frequency was up to 0.5 MHz higher than the critical frequency.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 11, pp. 939–950, November 2008. 相似文献
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14.
The effects of gold and Co-adsorbed carbon on the adsorption and thermal decomposition of acetic acid on Pd{111} 总被引:1,自引:0,他引:1
Owens TG Jones TE Noakes TC Bailey P Baddeley CJ 《The journal of physical chemistry. B》2006,110(42):21152-21160
The growth and annealing behavior of ultrathin Au films on Pd{111} were monitored with scanning tunneling microscopy (STM) and medium energy ion scattering (MEIS). The adsorption of acetic acid on both clean and deliberately carbon-contaminated bimetallic surfaces was investigated with reflection absorption infrared spectroscopy (RAIRS) and temperature-programmed desorption (TPD). We report that the surface chemistry of acetic acid is strongly modified by the presence of Au in the bimetallic surface which acts both to stabilize adsorbed acetate and to decrease the tendency of acetic acid to decompose on adsorption to produce adsorbed carbon. The adsorption of acetic acid at 300 K is found to cause measurable segregation of Pd to the surface for all surface compositions tested. 相似文献
15.
A primitive permutation group is said to be of twisted wreathtype if its socle is both non-abelian and regular. We reducethe study of such primitive permutation groups to the studyof maximal non-abelian simple sections of non-abeliansimple groups. 相似文献
16.
The technique of ferromagnetic resonance at 23 GHz has been used to determine the first three anisotropy constants of pure Ni down to 4.2K. A temperature and orientation dependent linewidth has also been observed. 相似文献
17.
Kate L. Baddeley Qun Cao Dr. Mark J. Muldoon Dr. Matthew J. Cook 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7726-7730
A palladium‐catalyzed oxidative reaction is reported which converts dihydropyrans to their corresponding ortholactone. The products are formed in good to excellent yields with a very high level of chemoselectivity and functional group tolerance. Mechanistic studies confirm that the reaction proceeds by a Wacker‐type mechanism. 相似文献
18.
A. Baddeley J. Møller A. G. Pakes 《Annals of the Institute of Statistical Mathematics》2008,60(3):627-649
For any point process in that has a Papangelou conditional intensity λ, we define a random measure of ‘innovations’ which has mean zero. When the
point process model parameters are estimated from data, there is an analogous random measure of ‘residuals’. We analyse properties
of the innovations and residuals, including first and second moments, conditional independence, a martingale property, and
lack of correlation. Some large sample asymptotics are studied. We derive the marginal distribution of smoothed residuals
by solving a distributional equivalence. 相似文献
19.
Robert W. Baddeley Cheryl E. Praeger Csaba Schneider 《Transactions of the American Mathematical Society》2008,360(2):743-764
A permutation group is innately transitive if it has a transitive minimal normal subgroup, which is referred to as a plinth. We study the class of finite, innately transitive permutation groups that can be embedded into wreath products in product action. This investigation is carried out by observing that such a wreath product preserves a natural Cartesian decomposition of the underlying set. Previously we classified the possible embeddings in the case where the innately transitive group projects onto a transitive subgroup of the top group. In this article we prove that the transitivity assumption we made in the previous paper was not too restrictive. Indeed, the image of the projection into the top group can only be intransitive when the finite simple group that is involved in the plinth comes from a small list. Even then, the innately transitive group can have at most three orbits on an invariant Cartesian decomposition. A consequence of this result is that if is an innately transitive subgroup of a wreath product in product action, then the natural projection of into the top group has at most two orbits.
20.
P. Lemmer M. Gunkel D. Baddeley R. Kaufmann A. Urich Y. Weiland J. Reymann P. Müller M. Hausmann C. Cremer 《Applied physics. B, Lasers and optics》2008,93(1):1-12
Far-field fluorescence techniques based on the precise determination of object positions have the potential to circumvent
the optical resolution limit of direct imaging given by diffraction theory. In order to use localization to obtain structural
information far below the diffraction limit, the ‘point-like’ components of the structure have to be detected independently,
even if their distance is lower than the conventional optical resolution limit. This goal can be achieved by exploiting various
photo-physical properties of the fluorescence labeling (‘spectral signatures’). In first experiments, spectral precision distance
microscopy/spectral position determination microscopy (SPDM) was limited to a relatively small number of components to be
resolved within the observation volume. Recently, the introduction of photoconvertable molecules has dramatically increased
the number of components which can be independently localized. Here, we present an extension of the SPDM concept, exploiting
the novel spectral signature offered by reversible photobleaching of fluorescent proteins. In combination with spatially modulated
illumination (SMI) microscopy, at the present stage, we have achieved an estimated effective optical resolution of approximately
20 nm in the lateral and 50 nm in the axial direction, or about 1/25th–1/10th of the exciting wavelength. 相似文献