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31.
We claim that physics has been constructed because three “philosophical” principles have been respected, namely, realism,
locality, and consistency. These principles lead to an interpretation of quantum mechanics (QM) in terms of local hidden-variables
theories (LHV). In order to prove that LHV have not been refuted, we analyze the empirical proofs of Bell's inequalities and
we argue that none is loophole-free. Then we propose a restricted QM that does not contain measurement postulates and that
does not claim that all state vectors (self-adjoint operators) are states (observables). The contradiction of such restricted
QM with Bell's inequality cannot be shown as a theorem, but only by the design of a loophole-free experiment. Finally, we
argue that noise has been underestimated in quantum theory. It does not appear in QM, but it is essential in quantum field
theory. We conjecture that noise will prevent the violation of Bell's inequality. 相似文献
32.
A. Longhetto G. Chabert D'Hieres L. Briatore H. Didelle E. Ferrero C. Giraud 《Il Nuovo Cimento C》1996,19(4):561-578
Summary One of the most intriguing problems concerning the interaction of subsynoptic and synoptic atmospheric flows with topographic
features is orographic cyclogenesis. A fully satisfactory prediction theory is not yet available, but a lot of efforts have
been made by theoreticians to implement reliable numerical models simulating the different phases of this complex phenomenon.
An attempt to perform a laboratory experiment to simulate physically this kind of interaction has been made by us, through
the generation of a baroclinic frontal system in the rotating hydraulic platform of the ?Coriolis Laboratory—LEGI-IMG—Grenoble?.
The adopted technique consists in a device which produces, at the interface separating two water layers of different density
(ϱ1 and ϱ2), a stream of stratified fluid whose density has an intermediate value ϱ1 < ϱm < ϱ2. This stream is generated at the height of the interface between the two layers; due to the rotation of the platform, the
attainment of geostrophic equilibrium brings about an intermediate-water flow running along a wall, giving rise to a three-layer
baroclinic structure which can represent some of the main outstanding features of an atmospheric frontal system impinging
on a mountain. In a well-defined range of the Rossby and Burger numbers, the instability of this current gives rise to a couple
of persistent cyclonic and anticyclonic vortices, whose horizontal dimensions and vertical extents reproduce quite faithfully
the synoptic situation supporting the onset of the orographic cyclogenesis, with its characteristic cold front stretching
between the two vortex structures. It is enough to place an obstacle of a suitable size in the proper geographic position,
to make the cyclogenesis start. The first results of our simulations have been encouraging, showing the occurrence of lee
cyclogenesis when the stream conditions in our model correspond to the synoptic features which have been recognized as the
precursors of orographic cyclogenesis in the lee of the Alps. 相似文献
33.
In this paper, we study prime ideals and radicals of centred extensions of rings. Obtained results are applied to tensor products
of algebras over commutative rings.
This research was partially supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Brazil. The
second-named author was also supported by KBN grant 2 P301 035 06. 相似文献
34.
The kinetics of the gas-phase thermal isomerization between trans- and cis-1,2-bis(trifluoromethyl)-1,2,3,3-tetrafluorocyclopropane as well as their decomposition to trans- and cis-perfluoro-2-butene, respectively, and CF2, was studied in the temperature range of 473–533°K, with an initial pressure of reactant of 1.5 to 7.0 Torr. Some runs were also made with the addition of SF6 as an inert gas up to a total pressure of 100 Torr. The reactions are first order and homogeneous. The rate constants for the geometrical isomerization fit the following Arrhenius relations: and the corresponding equations for the decomposition of the trans and cis-cyclopropane are . 相似文献
35.
Summary Joerchel's method is applied to SAXS spectra of a poly(amido-amine)-heparin complex in aqueous non diluted solutions, showing a noticeable interference effect. The results are compared with those obtained by the classical Guinier analysis applied to diluted solutions of the complex.
Zusammenfassung SAXS-Spektren eines Poly(amido-amin)-Heparin-Komplexes in nicht verdünnten wäßrigen Lösungen, die bemerkenswerte Interferenzeffekte zeigen, wurden mittels der Joerchel'schen Methode analysiert. Die Ergebnisse wurden mit den durch die klassische Analyse von Guinier an verdünnten wäßrigen Komplexlösungen erhaltenen verglichen.相似文献
36.
Methylvinylpyridine-butadiene copolymers vulcanized by various α, ω dibromo-alkanes were investigated by X-ray small angle scattering. In these systems, employing the Hosemann-Joerchel analysis, only one cluster dimension of about 45 Å has been found with a polydispersity not exceeding 35 per cent. Stretched rubbers show interference effects both in the meridional and equatorial directions. 相似文献
37.
M. Dehlinger C. Fauquet F. Jandard A. Bjeoumikhov S. Bjeoumikhova R. Gubzhokov A. Erko I. Zizak D. Pailharey S. Ferrero B. Dahmani D. Tonneau 《X射线光谱测定》2013,42(6):456-461
Capillary optics are used for X‐ray fluorescence micro‐analysis using the Cu Kα line provided by a rotating anode. The excitation beam is focused using a polycapillary lens on a Co–Ti sample. Cylindrical glass capillaries of various diameters are fitted to the X‐ray detector (Energy Dispersive X‐Ray (EDX) analyzer) and displaced along the irradiated zone of the sample. The fluorescence is studied as a function of capillary position. Good agreement is found between experimental and calculated lateral widths of the fluorescence collection, taken into account the cylindrical capillary critical angles relevant in the experiment. The influence of the cylindrical capillary diameter on the signal level detected is studied to estimate the possibility of lateral resolution increase of X‐ray fluorescence technique both in‐lab and in synchrotron environment. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
38.
39.
DC Muddiman AP Null JC Hannis 《Rapid communications in mass spectrometry : RCM》1999,13(12):1201-1204
Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICRMS) has been used to determine the mass of a double-stranded 500 base-pair (bp) polymerase chain reaction (PCR) product with an average theoretical mass of the blunt-ended (i.e. unadenylated) species of 308 859.35 Da. The PCR product was generated from the linearized bacteriophage Lambda genome which is a double-stranded template. Utilization of ethanol precipitation in tandem with a rapid microdialysis step to purify and desalt the PCR product was crucial to obtain a precise mass measurement. The PCR product (0.8 pmol/μL) was electrosprayed from a solution containing 75% acetonitrile, 25 mM piperidine, and 25 mM imidazole and was infused at a rate of 200 nL/min. The average molecular mass and the corresponding precision were determined using the charge-states ranging from 172 to 235 net negative charges. The experimental mass and corresponding precision (reported as the 95% confidence interval of the mean) was 309 406 +/- 27 Da (87 ppm). The mass accuracy was compromised due to the fact that the PCR generates multiple products when using Taq polymerase due to the non-template directed 3'-adenylation. This results in a mixture of three PCR products with nearly identical mass (i.e. blunt-ended, mono-adenylated and di-adenylated) with unknown relative abundances that were not resolved in the spectrum. Thus, the experimental mass will be a weighted average of the three species which, under our experimental conditions, reflects a nearly equal concentration of the mono- and di-adenylated species. This report demonstrates that precise mass measurements of PCR products up to 309 kDa (500 bp) can be routinely obtained by ESI-FTICR requiring low femtomole amounts. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
40.
A. B. D. Brown C. Ferrero T. Narayanan A. R. Rennie 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,11(3):481-489
The structure and phase behaviour of a colloidal dispersion of plate-like particles are described. The plates are nickel (II)
hydroxide and have short-range, repulsive interactions and a low polydispersity. As the concentration of the plates is increased,
an equilibrium phase separation between a columnar phase and a less ordered phase is observed. Complementary measurements
using small-angle neutron and small-angle X-ray scattering have been used to distinguish the columnar phase from other possible
ordered structures. Previously isotropic-nematic phase transitions have been observed [#!ref1!#], however this dispersion
forms the more highly ordered columnar phase, due to the aspect ratio and the low polydispersity of the plate-like particles.
The concentration at which phase separation occurs, increases as the range of the particle interactions is reduced. This system
provides an interesting model for comparison with theory and calculations of structures in liquid crystal and mesophase in
which the particle interactions can be altered.
Received 24 February 1999 相似文献