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61.
B. J. Rendle und G. L. Franklin 《Fresenius' Journal of Analytical Chemistry》1939,118(7-8):292-293
Ohne Zusammenfassung 相似文献
62.
Roberto Beneduci James Brooke Ray Curran Franklin E. SchroeckJr. 《International Journal of Theoretical Physics》2011,50(12):3682-3696
We consider the Hamilton formulation as well as the Hamiltonian flows on a symplectic (phase) space. These symplectic spaces
are derivable from the Lie group of symmetries of the physical system considered. In Part 2 of this work, we then obtain the
Hamiltonian formalism in the Hilbert spaces of square integrable functions on the symplectic spaces so obtained. 相似文献
63.
64.
W. Dick A. Karl R. D. Evans Frau P. Curie F. Behounek W. Bothe N. E. Dorsey P. Ludewig W. A. Sokolow A. Piccard L. Meylan A. J. Allen J. A. C. Teegan A. S. Eve J. Katzmann C. L. Utterbeck D. Devaputra R. G. Franklin E. Witte H. A. Doerner und W. M. Hoskins 《Fresenius' Journal of Analytical Chemistry》1934,98(5-6):194-207
Ohne Zusammenfassung 相似文献
65.
The sodium anion of trans-1,3-dithiane-1,3-dioxide reacts with unhindered aromatic and heteroaromatic aldehydes to give adducts with 95:5 to 97:3 diastereoselectivity. 相似文献
66.
67.
Smyth WF Morgan JL O'Kane E Millar TJ Ramachandran VN 《Rapid communications in mass spectrometry : RCM》2011,25(9):1308-1314
Electrospray ionisation quadrupole time-of-flight tandem mass spectrometry (ESI-QTOF-MS/MS) has been used for characterisation of a selection of naturally occurring and synthetic coumarins from different structural classes. The product ions, suggested in earlier studies by electrospray ionisation ion trap mass spectrometry (ESI-MS(n)), are unequivocally established for the representative coumarins by virtue of accurate mass measurement. Synthetic coumarins that are unsubstituted in the heterocyclic ring give rise to a major product ion by loss of CO(2), whereas those substituted in the heterocyclic ring generally undergo alternative fragmentation releasing neutral species such as ketene or methyl ketene. Naturally occurring coumarins, unsubstituted in the heterocyclic ring and substituted in the benzene ring with chains or rings of hydrocarbons and oxygen, principally fragment at the side chain releasing unsaturated hydrocarbons. The ESI-QTOF-MS/MS behaviour of some naturally occurring and synthetic quinolines which are structurally similar or fragment similarly are included where appropriate. 相似文献
68.
Oh HB Leach FE Arungundram S Al-Mafraji K Venot A Boons GJ Amster IJ 《Journal of the American Society for Mass Spectrometry》2011,22(3):582-590
The structural characterization of glycosaminoglycan (GAG) carbohydrates by mass spectrometry has been a long-standing analytical
challenge due to the inherent heterogeneity of these biomolecules, specifically polydispersity, variability in sulfation,
and hexuronic acid stereochemistry. Recent advances in tandem mass spectrometry methods employing threshold and electron-based
ion activation have resulted in the ability to determine the location of the labile sulfate modification as well as assign
the stereochemistry of hexuronic acid residues. To facilitate the analysis of complex electron detachment dissociation (EDD)
spectra, principal component analysis (PCA) is employed to differentiate the hexuronic acid stereochemistry of four synthetic
GAG epimers whose EDD spectra are nearly identical upon visual inspection. For comparison, PCA is also applied to infrared
multiphoton dissociation spectra (IRMPD) of the examined epimers. To assess the applicability of multivariate methods in GAG
mixture analysis, PCA is utilized to identify the relative content of two epimers in a binary mixture. 相似文献
69.
Tung VC Huang JH Tevis I Kim F Kim J Chu CW Stupp SI Huang J 《Journal of the American Chemical Society》2011,133(13):4940-4947
Heterojunctions between different graphitic nanostructures, including fullerenes, carbon nanotubes and graphene-based sheets, have attracted significant interest for light to electrical energy conversion. Because of their poor solubility, fabrication of such all-carbon nanocomposites typically involves covalently linking the individual constituents or the extensive surface functionalization to improve their solvent processability for mixing. However, such strategies often deteriorate or contaminate the functional carbon surfaces. Here we report that fullerenes, pristine single walled carbon nanotubes, and graphene oxide sheets can be conveniently coassembled in water to yield a stable colloidal dispersion for thin film processing. After thermal reduction of graphene oxide, a solvent-resistant photoconductive hybrid of fullerene-nanotube-graphene was obtained with on-off ratio of nearly 6 orders of magnitude. Photovoltaic devices made with the all-carbon hybrid as the active layer and an additional fullerene block layer showed unprecedented photovoltaic responses among all known all-carbon-based materials with an open circuit voltage of 0.59 V and a power conversion efficiency of 0.21%. The ease of making such surfactant-free, water-processed, carbon thin films could lead to their wide applications in organic optoelectronic devices. 相似文献
70.
Wolstenholme DJ Titah JT Che FN Traboulsee KT Flogeras J McGrady GS 《Journal of the American Chemical Society》2011,133(41):16598-16604
The solid-state structures of LiNH(2)BH(3) and NaNH(2)BH(3) have been shown recently to exhibit intricate M(δ+)···(δ-)H-B and N-H(δ+)···(δ-)H-B interactions. However, closer inspection of these structures reveals additional homopolar H···H interactions, viz., B-H(δ-)···(δ-)H-B and N-H(δ+)···(δ+)H-N, which contribute to the relative stability of the extended structures of these crystalline materials. In addition, an NMR study of the isotopomer LiND(2)BH(3) shows that a significant quantity of H(2) is desorbed thermally along with HD, which can only arise from hydride-hydride interactions, either directly from B-H(δ-)···(δ-)H-B moieties or indirectly through the participation of Li-H intermediates. 相似文献