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961.
Stepan Stehlik Tomas Kohoutek Miloslav Frumar Toru Hara Kazuyuki Ueda 《Journal of solid state chemistry》2010,183(1):144-149
This article describes the preparation of multi-walled carbon nanotube—chalcogenide glass composite by direct synthesis and the melt-quenching method. The carbon nanotubes—chalcogenide glass composite was characterized by high-resolution transmission electron microscopy (HRTEM), TEM/energy-dispersive X-ray spectroscopy, low energy electron excited X-ray spectroscopy, Raman spectroscopy, spectroscopic ellipsometry, microhardness, and impedance spectroscopy. CNTs-AgAsS2 glass composite possess highly increased ionic conductivity, from σ25 °C=4.38±0.0438×10−6 to σ25 °C=6.57±0.0657×10−6 S cm−1 and decreased refractive index from n=2.652 to 2.631 at the wavelength λ=1.55 μm. 相似文献
962.
Thomas TD Kukk E Ouchi T Yamada A Fukuzawa H Ueda K Püttner R Higuchi I Tamenori Y Asahina T Kuze N Kato H Hoshino M Tanaka H Lindblad A Sæthre LJ 《The Journal of chemical physics》2010,133(17):174312
Recoil-induced rotational excitation accompanying photoionization has been measured for the X, A, and B states of N(2)(+) and CO(+) over a range of photon energies from 60 to 900 eV. The mean recoil excitation increases linearly with the kinetic energy of the photoelectron, with slopes ranging from 0.73×10(-5) to 1.40×10(-5). These slopes are generally (but not completely) in accord with a simple model that treats the electrons as if they were emitted from isolated atoms. This treatment takes into account the atom from which the electron is emitted, the molecular-frame angular distribution of the electron, and the dependence of the photoelectron cross section on photon energy, on atomic identity, and on the type of atomic orbital from which the electron is ejected. These measurements thus provide a tool for investigating the atomic orbital composition of the molecular orbitals. Additional insight into this composition is obtained from the relative intensities of the various photolines in the spectrum and their variation with photon energy. Although there are some discrepancies between the predictions of the model and the observations, many of these can be understood qualitatively from a comparison of atomic and molecular wavefunctions. A quantum-mechanical treatment of recoil-induced excitation predicts an oscillatory variation with photon energy of the excitation. However, the predicted oscillations are small compared with the uncertainties in the data, and, as a result, the currently available results cannot provide confirmation of the quantum-mechanical theory. 相似文献
963.
Masamichi Sakai Kazumasa Okada Keiichi Ohno Kiyohiko Tabayashi 《Journal of mass spectrometry : JMS》2010,45(3):306-312
Fragmentation of the pyridine ring upon K‐shell excitation/ionization has been studied with gaseous 2‐, 3‐ and 4‐methylpyridine by the electron‐impact method. Ab initio molecular orbital (MO) calculations were also carried out to explore electronic states correlating with specific fragments. Some specific fragmentation channels were identified from the ionic fragments enhanced characteristically at the N 1s edge. Yields of the C2HN+ and C5H5+/C5H6+ ions show that the fission of the N? C2 and C4? C5/C5? C6 bonds of the ring is likely to occur after the N 1s excitation and ionization. Ab initio MO calculations for the 2‐methylpyridine molecule indicate that the dissociation channels to produce these ions are only accessible through the excited states of the parent molecular dication, which can be formed by Auger decays after the N 1s ionization. Fragment ions via hydrogen rearrangement are produced as well, but the rearrangement is not a phenomenon specific to the K‐shell excitation/ionization. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
964.
965.
We studied the temperature dependence of high-density carrier dynamics in as-grown and thermally annealed Ge quantum dots (QDs) in silicon crystals. In as-grown and thermally annealed samples, photoluminescence (PL) intensity exhibited a power-law dependence on the excitation intensity and its power-law index was ~ 0.7 at low temperatures. With increasing measurement temperature, PL intensity decreased and the index of the power-law function increased up to ~ 1.5, in which carrier recombination dynamics is dominated by a single carrier trapping. Moreover, in thermally annealed QDs, the index of the power law increased more rapidly than as-grown QDs, suggesting that the carrier recombination dynamics drastically changed in thermally annealed QDs. Effects of Ge/Si interface on high-density carrier recombination process are discussed. 相似文献
966.
Matsui H Ueda M Makino A Kimura S 《Chemical communications (Cambridge, England)》2012,48(49):6181-6183
A 2nd generation polyamideamine (PAMAM) dendrimer bearing right-handed helices to its eight terminals was shown to accommodate eight left-handed helices via stereocomplex formation to generate molecular assemblies of disk structure with 13-14 nm diameter and 6 nm thickness. 相似文献
967.
SC Lee A Ueda H Kamo K Takahashi M Uruichi K Yamamoto K Yakushi A Nakao R Kumai K Kobayashi H Nakao Y Murakami H Mori 《Chemical communications (Cambridge, England)》2012,48(69):8673-8675
A unique N(+)-HN hydrogen-bonded (H-bonded) dimer motif based on partially oxidized pyridyl-substituted TTF was constructed in the charge-transfer complex. The charge ordering in the TTF column by the charge disproportionation in the dimer regulates the arrangement of the H-bonded proton, evidencing the proton-electron coupled state. 相似文献
968.
We provide a comprehensive report on scale-invariant fluctuations of growing interfaces in liquid-crystal turbulence, for which we recently found evidence that they belong to the Kardar-Parisi-Zhang (KPZ) universality class for 1+1 dimensions [Takeuchi and Sano in Phys. Rev. Lett. 104:230601, 2010; Takeuchi et al. in Sci. Rep. 1:34, 2011]. Here we investigate both circular and flat interfaces and report their statistics in detail. First we demonstrate that their fluctuations show not only the KPZ scaling exponents but beyond: they asymptotically share even the precise forms of the distribution function and the spatial correlation function in common with solvable models of the KPZ class, demonstrating also an intimate relation to random matrix theory. We then determine other statistical properties for which no exact theoretical predictions were made, in particular the temporal correlation function and the persistence probabilities. Experimental results on finite-time effects and extreme-value statistics are also presented. Throughout the paper, emphasis is put on how the universal statistical properties depend on the global geometry of the interfaces, i.e., whether the interfaces are circular or flat. We thereby corroborate the powerful yet geometry-dependent universality of the KPZ class, which governs growing interfaces driven out of equilibrium. 相似文献
969.
Tao Chen Atsushi Yamaguchi Kazumasa Igarashi Naoya Nakagawa Hidenori Nishioka Hiroyuki Asanuma Mikio Yamashita 《Optics Communications》2012,285(6):1206-1211
The femtosecond photoisomerization processes of trans (T) 4-carboxy-2′,6′-dimethylazobenzen, which has been employed recently as an efficient photoregulator of DNA hybridization, were clarified by the rate equation analysis of measured transient absorbance changes with (350 nm) and without (380 nm) ground-state absorption of both the reactant (T) and photoproduct (cis: C) isomers under S2T-band excitation (360 nm, 150 fs pump): after excitation to the S2T state with a 450-fs lifetime, ~ 1.5% of the T-molecules in the S2T state are isomerized to the C-form within ~ 6 ps through the intermediate state (so called bottleneck state), but most of those return back to the T ground-state S2T via the internal conversion processes with an ultrafast kinetic rate of 2.2 × 1012 s? 1. Moreover, the rate equation analysis enables us to determine the T-to-C photoisomerization rate ηT,C per pump pulse to be 0.0011 at the pump energy of 80 nJ from the amplitude A3,350 of the offset component in the 350-nm probe signal, and to obtain the photoisomerization quantum yield ΦT,C = 0.094. The latter value is slightly lower than that of T-azobenzene, and well agrees with that (ΦT,C = 0.097) measured by the conventional CW irradiation method using a photostationary state. 相似文献
970.
We investigate a global complexity bound of the Levenberg–Marquardt Method (LMM) for nonsmooth equations. The global complexity
bound is an upper bound to the number of iterations required to get an approximate solution that satisfies a certain condition.
We give sufficient conditions under which the bound of the LMM for nonsmooth equations is the same as smooth cases. We also
show that it can be reduced under some regularity assumption. Furthermore, by applying these results to nonsmooth equations
equivalent to the nonlinear complementarity problem (NCP), we get global complexity bounds for the NCP. In particular, we
give a reasonable bound when the mapping involved in the NCP is a uniformly P-function. 相似文献