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81.
Morelos A Albuquerque IF Bondar NF Carrigan RA Chen D Cooper PS Dai Lisheng Denisov AS Dobrovolsky AV Dubbs T Endler AM Escobar CO Foucher M Golovtsov VL Gottschalk H Gouffon P Grachev VT Khanzadeev AV Kubantsev MA Kuropatkin NP Lach J Lang Pengfei Li Chengze Li Yunshan Luksys M Mahon JR McCliment E Newsom C Pommot Maia MC Samsonov VM Schegelsky VA Shi Huanzhang Smith VJ Tang Fukun Terentyev NK Timm S Tkatch II Uvarov LN Vorobyov AA Yan Jie Zhao Wenheng Zheng Shuchen Zhong Yuanyuan 《Physical review letters》1993,71(14):2172-2175
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83.
A novel mixed-ligand nickel complex, [Ni(PMBP—PNH) (Py)3], [PMBP—PNH=N-(1-phenyl-3-methyl-4-benzylidene-5-pyrazolone) p-nitrobezoylhydrazide; Py = pyridine], has been synthesized by the hydrothermal method and characterized by elemental analysis, IR spectrum, thermal analysis, and single-crystal X-ray diffraction. The X-ray diffraction reveals that the nickel (II) ion in the title complex is in a slightly distorted octahedral arrangement of the ONO donor atoms of primary ligand PMBP-PNH and three N-donor atoms in the secondary ligand pyridine. 相似文献
84.
Dumitru Ivascu Gabriel Burstein 《Journal of Mathematical Analysis and Applications》1985,106(1):171-179
Some results are given on the homology groups of the abstract simplicial complex associated to a multivariable control system, as an extension of the central result of J. Casti (J. Math. Anal. Appl.68 (1979), 347–370) to the multivariable case. The method used is “polyhedral dynamics” as termed by J. Casti, who introduced it. A given control system is mapped into a simplicial complex and then its homological structure is studied. These results, obtained in the multivariable case by the use of the Mayer-Vietoris homology sequence and of the relative homology sequence, present topological invariants for control systems thus creating the possibility of a new topological classification of multivariable systems. An example is given to clarify the approach. 相似文献
85.
Lang ND 《Physical review letters》1985,55(2):230-233
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87.
Zusammenfassung An Stelle eines Choppers wird zur Modulation des flammenspektrometrischen Signals die Probenflüssigkeit periodisch der Flamme zugeführt (intermittierende Zerstäubung). Es wird zunächst über die beobachtete Eigenmodulation der Zerstäubung berichtet und danach über die intermittierende Zerstäubung mit Frequenzen bis zu 50 Hz. Anschließend wird an Hand von Beispielen gezeigt, daß sich die intermittierende Zerstäubung als besonders vorteilhaft in der Absorptions-Flammenspektrometrie erweist. Wird das Gleichlicht des Hintergrundstrahlers mittels der intermittierenden Zerstäubung in der Flamme moduliert und ein Wechselstromverstärker verwendet, so fallen der 0- und 100%-Durchlässigkeitspunkt zusammen. Bei der Registrierung über die Wellenlänge werden dann nur solche Linien angezeigt, welche in der Flamme das eingestrahlte Licht absorbieren.
Der Fa. Siemens-Reiniger Werke AG., Erlangen, und insbesondere Herrn Ing. Engel danken wir auch an dieser Stelle für die leihweise Überlassung des Flüssigkeitsstrahloscillographen Cardirex 31 B. — Herrn K. RÜdiger danken wir für die wertvollen Hinweise und für die Durchführung der Werkstattarbeiten. 相似文献
Summary For modulating the flame spectrometric signal without using a chopper the sample is introduced into the flame periodically (intermittent atomisation). First, the observed self-modulation of the atomisation is described and subsequently the intermittent atomisation with frequencies up to 50 cps. Some examples demonstrate that intermittent atomisation proves to be especially advantageous in absorption flame spectrometry. When modulating the light of the dc-operated line source by means of intermittent atomisation and using ac-amplification of the modulated signal the 0- and 100%-transmittance points of the transmittance scale are the same. When scanning over the wave length only such lines are detected which absorb the light of the background source.
Der Fa. Siemens-Reiniger Werke AG., Erlangen, und insbesondere Herrn Ing. Engel danken wir auch an dieser Stelle für die leihweise Überlassung des Flüssigkeitsstrahloscillographen Cardirex 31 B. — Herrn K. RÜdiger danken wir für die wertvollen Hinweise und für die Durchführung der Werkstattarbeiten. 相似文献
88.
[reaction: see text] 5,10,15,20-Tetrakis(m-hydroxyphenyl)porphyrin (m-THPP) yielded novel quinonoid porphyrins upon irradiation in aqueous methanol. True photobleaching was observed for 5,10,15,20-tetrakis(m-hydroxyphenyl)chlorin (m-THPC) and 5,10,15,20-tetrakis(m-hydroxyphenyl)bacteriochlorin (m-THPBC) under the same conditions; several fragmentation products (imides, methyl p-hydroxybenzoate, dipyrrin derivatives) were recognized. 相似文献
89.
Ab initio potential energy and transition dipole moment surfaces are presented for the five lowest singlet even symmetry electronic states of ozone. The surfaces are calculated using the complete active space self consistent field method followed by contracted multireference configuration interaction (MRCI) calculations. A slightly reduced augmented correlation consistent valence triple-zeta orbital basis set is used. The ground and excited state energies of the molecule have been computed at 9282 separate nuclear geometries. Cuts through the potential energy surfaces, which pass through the geometry of the minimum of the ground electronic state, show several closely avoided crossings. Close examination, and higher level calculations, very strongly suggests that some of these seemingly avoided crossings are in fact associated with non-symmetry related conical intersections. Diabatic potential energy and transition dipole moment surfaces are created from the computed ab initio adiabatic MRCI energies and transition dipole moments. The transition dipole moment connecting the ground electronic state to the diabatic B state surface is by far the strongest. Vibrational-rotational wavefunctions and energies are computed using the ground electronic state. The energy level separations compare well with experimentally determined values. The ground vibrational state wavefunction is then used, together with the diabatic B<--X transition dipole moment surface, to form an initial wavepacket. The analysis of the time-dependent quantum dynamics of this wavepacket provides the total and partial photodissociation cross sections for the system. Both the total absorption cross section and the predicted product quantum state distributions compare well with experimental observations. A discussion is also given as to how the observed alternation in product diatom rotational state populations might be explained. 相似文献