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571.
Mitsutaka Okumura Yohei Nishimura Yasutaka Kitagawa Takashi Kawakami Kizashi Yamaguchi 《Polyhedron》2009,28(9-10):1768-1775
Hybrid density functional theory (HDFT) calculations have been carried out for clusters of p-NPNN extracted from the experimental crystal structures of the α-, β-, γ- and δ-phases in order to investigate the weak magnetic interactions between the organic radicals theoretically. From the systematic HDFT calculations for β- and γ-phase p-NPNN clusters, it was found that the magnetic long-range ferromagnetic and antiferromagnetic orderings would be presented in the β- and γ-phase p-NPNN crystals, respectively. 相似文献
572.
We have prepared DPP-hematin (DPP?=?2, 3, 5, 7, 8, 10, 12, 13, 15, 17, 18, 20-dodecaphenylporphyrin), and characterized it by Mössbauer and magnetic measurements. It is concluded that DPP-hematin is most likely a monomer, as is expected from the distorted nonplanar structure of the porphyrin, in contrast to usual hematins: hematins derived from usual porphyrins are μ-oxo dimers. 相似文献
573.
Quantum teleportation is rigorously demonstrated with coherent entangled states given by beam splittings. The mathematical
scheme of beam splitting has been used to study quantum communication [2] and quantum stochastic [8]. We discuss the teleportation
process by means of coherent states in this scheme for the following two cases: (1) Delete the vacuum part from coherent states,
whose compensation provides us a perfect teleportation from Alice to Bob. (2) Use fully realistic (physical) coherent states,
which gives a non-perfect teleportation but shows that it is exact when the average energy (density) of the coherent vectors
goes to infinity. We show that our quantum teleportation scheme with coherent entangled state is more stable than that with
the EPR pairs which was previously discussed.
Received: 21 January 2000 / Accepted: 23 April 2001 相似文献
574.
Zhong Huang Yohei Ishida Tetsu Yonezawa 《Angewandte Chemie (International ed. in English)》2019,58(38):13411-13415
The synthesis of high‐purity and high‐yield Au25 clusters protected by the basic pyridyl ethanethiol (HSCH2CH2Py, 4‐PyET and 2‐PyET) is presented. Single‐crystal X‐ray diffraction of the [Au25(4‐PyET)18]??Na+ clusters has revealed a structure similar to that known for the phenyl ethanethiolate analogue, but with pyridyl‐N coordination to Na+, a more relaxed ligand shell, and a profoundly layered arrangement in the solid state. Because of the pendant Py moiety, the [Au25(PyET)18]? clusters are endowed with unique (de)protonation equilibria, which has been characterized in detail by UV/Vis absorption and 1H NMR spectroscopy. [Au25(PyET)18]? clusters showed an unexpectedly H+‐dependent solubility that is tunable in aqueous and organic solvents. The successful synthesis of the basic Py‐terminated thiolate‐protected Au25 clusters paves the way to realize a new family of metalloid clusters possessing basic properties. 相似文献
575.
Ryotaro Aso Yohei Ogawa Takehiro Tamaoka Hideto Yoshida Seiji Takeda 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(45):16174-16178
Understanding the atomic and molecular phenomena occurring in working catalysts and nanodevices requires the elucidation of atomic migration originating from electronic excitations. The progressive atomic dynamics on metal surface under controlled electronic stimulus in real time, space, and gas environments are visualized for the first time. By in situ environmental transmission electron microscopy, the gas molecules introduced into the biased metal nanogap could be activated by electron tunneling and caused the unpredicted atomic dynamics. The typically inactive gold was oxidized locally on the positive tip and field‐evaporated to the negative tip, resulting in the atomic reconstruction on the negative tip surface. This finding of a tunneling‐electron‐attached‐gas process will bring new insights into the design of nanostructures such as nanoparticle catalysts and quantum nanodots and will stimulate syntheses of novel nanomaterials not seen in the ambient environment. 相似文献
576.
ZnO crystals were synthesized from basic aqueous solutions including zincate ions stabilized with triethanolamine (N(C2H4OH)3, teaH3) by heating at 60°C. The influence of the basicity of the solutions on the morphology of the ZnO crystals was examined. The aqueous solutions were prepared using ZnSO4·7H2O, N(CH3)4OH (TMAOH), and teaH3 as a zinc source, a base, and a stabilizer, respectively, at a zinc concentration of 0.2 M at a teaH3 / Zn molar ratio of 4. Clear solutions were obtained at a molar ratio of TMAOH / Zn ≥ 3.0. When the clear solutions, in which glass or polyester substrates were placed, were heated at 60°C, agglomerates of ZnO crystals were deposited on the substrates in the TMAOH / Zn range from 3.0 to 3.6. With increasing the TMAOH / Zn ratio, the shape of the resulting ZnO crystals changed from a short asymmetric column with a hexagonal flat edge and a rounded one, through a rocket‐like shape formed by intergrowth, to a hexagonal rod. Although no films of ZnO were formed, ZnO crystals with different shapes were synthesized. When the glass substrates pre‐coated with a ZnO thin film by a sol‐gel method were used, highly oriented, dense ZnO films were formed. The films consisted of rod‐like crystals aligned normal to the substrate surface. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
577.
Yohei Ogawa Mutsuto Kawahara 《International Journal of Computational Fluid Dynamics》2013,27(4):243-251
This paper presents a numerical method of shape optimization of a body located in an incompressible viscous flow described by the Stokes and Oseen equations. The purpose of this study is to find the optimal shape that minimizes the fluid forces subjected to the body. The formulation of the shape optimization is based on the optimal control theory. The first thing that should be carried out in the optimal control theory is to define a performance function, which expresses the optimal shape. In this study, the fluid forces minimization problem is treated, i.e. fluid forces are directly used in the performance function. The performance function must be minimized subject to the basic equation. The optimal shape, which minimizes the fluid force, is pursued in this paper. This problem can be transformed into the minimization problem without constraint conditions by the Lagrange multiplier. As a numerical example, drag force minimization problems of a body located in low Reynolds number flows are carried out. 相似文献
578.
Akira Nagai Ryo Nishimura Yohei Hattori Eri Hatano Ayako Fujimoto Masakazu Morimoto Nobuhiro Yasuda Kenji Kamada Hikaru Sotome Hiroshi Miyasaka Satoshi Yokojima Shinichiro Nakamura Kingo Uchida 《Chemical science》2021,12(34):11585
Here, we present single crystalline capsules of a photoresponsive molecule produced by simple recrystallization from organic solutions without direct human processing. During the crystal growth process, a movie was taken of the capsule taking in the organic solution. The capsules responded rapidly (<1 s) to the UV light stimuli and released the captured solution or solute. In principle, they can take in any substance dissolved in organic solvents, and their size can be controlled. Moreover, the capsule can be broken by multi-photon excitation using a near-infrared laser within the biological window. Furthermore, because the molecular packing in the crystal is unidirectional, the response can be controlled by the polarization of the light. This study shows the new potential of photoresponsive molecules.A novel diarylethene formed “crystalline capsules” containing liquid inclusions, and chemicals trapped in the capsules were released by photoinduced breaking. Operations by multiphoton and linear polarized light were demonstrated. 相似文献
579.
Stone N.J. White G.N. Rikovska J. Ohya S. Giles T.J. Towner I.S. Brown B.A. Fogelberg B. Jacobsson L. Hjorth-Jensen M. 《Hyperfine Interactions》1999,120(1-8):645-649
Recent on-line nuclear orientation measurements of nuclear magnetic dipole moments by the method of NMR on oriented nuclei
(NMR/ON) have yielded significant new odd-A moments. These include those closest to double magic 132Sn, namely, 133Sb [132Sn plus one g7/2+ proton] and 133Tem [132Sn with a pair of g7/2+ protons and one hole in the h11/2- neutron sub-shell]. These close-to-double-magic results allow stringent tests of nuclear moment theory including, as main
contributions to deviations from the simple free nucleon (Schmidt limit) values, configuration mixing in the nuclear wavefunction
and mesonic exchange current modification to the dipole moment operator. Comparison with theoretical prediction, using established
approaches to both these corrections, is discussed showing success in medium mass nuclei comparable to results previously
established in light [to 40Ca] and heavy [near 208Pb] nuclei.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
580.
White G.N. Stone N.J. Rikovska J. Ohya S. Giles T.J. Towner I.S. Brown B.A. Fogelberg B. Jacobsson L. Hjorth-Jensen M. 《Hyperfine Interactions》1999,120(1-8):651-655
Recent on-line nuclear orientation measurements of odd-A nuclear magnetic dipole moments of odd-A Sb, Te and I isotopes by
the method of NMR on oriented nuclei mean that we now have complete series of odd-A moments up to, and including, those closest
to the double shell closure at 132Sn. In this paper we consider the systematic changes in the measured moments as a function of proton number for the isotonic
sequence 133Sb [g7/2+]1–139La [g7/2+]7 and as a function of neutron number for the isotopic sequences 125-133Sb and 127-135I and their interpretation using collective and shell model approaches.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献