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111.
Gabriele P. Stiller Thomas von ClarmannBernd Funke Norbert GlatthorFrank Hase Michael HöpfnerAndrea Linden 《Journal of Quantitative Spectroscopy & Radiative Transfer》2002,72(3):249-280
The accuracy of trace gas abundances retrieved from spectrally resolved infrared limb emission measurements relies, among other things, on the appropriate modelling of radiative transfer through the actual atmosphere. We quantify the mapping of several commonly applied simplifications in radiative transfer modelling on the trace gas abundances retrieval error at the example of the Michelson interferometer for passive atmospheric sounding (MIPAS)/environmental satellite (ENVISAT) space borne Fourier transform infra-red limb emission experiment. The Karlsruhe optimized and precise radiative transfer algorithm (KOPRA) which was used as a tool for this study will be introduced. KOPRA supports accurate modelling of the particular instrument requirements of MIPAS and the observation scenarios during the ENVISAT mission, in particular with respect to its viewing direction and its altitude coverage of the atmosphere. We show that disregarding of horizontal temperature inhomogeneities and non-local thermodynamic equilibrium effects, insufficient accuracy in modelling of field-of-view and apodisation effects, and disregarding individual profiles of isotopic species play the key roles in radiative transfer modelling and lead to systematic retrieval errors which can by far exceed the expected random retrieval error caused by measurement noise. 相似文献
112.
A total synthesis of seneciphyllic acid, the necic acid of the Senecio alkaloid seneciphylline, is reported. 相似文献
113.
Vertical ionization potentials for singlet and triplet methylene are calculated by a CI perturbation method based on ab initio SCF molecular orbitals (6–31 G** basis). The shape and vibrational fine structure of the first photoelectron band are investigated using the MINDO/3 method. The computed singlet-triplet splitting for methylene is 16.4 kcal/mol, in reasonable agreement with the experimental value of 19.5 kcal/mol. 相似文献
114.
Jorma Matikainen Seppo KaltiaMaija Ala-Peijari Ninna Petit-GrasKirsi Harju Jaakko HeikkiläRaija Yksjärvi Tapio Hase 《Tetrahedron》2003,59(4):567-573
Heating a mixture formed by alkali isomerization of methyl linolenoate (1) produces a complex mixture with the bicyclic hexahydroindenoic esters 4β-(7-methoxycarbonylheptyl)-5α-methyl-2,3,3aα,4,5,7aαhexahydroindene (CL5) and 4β-ethyl-5α-(6-methoxycarbonylhexyl)-2,3,3aα,4,5,7aα-hexahydroindene (CL6) as main components. Similar isomerization reactions of three synthetic model compounds, methyl 9Z,13E,15Z-octadecatrienoate (2), 9Z,14E,16E-octadecatrienoate (4) and 9Z,11E,15Z-octadecatrienoate (5) corroborated the results obtained with alkali isomerized methyl linolenoate. 相似文献
115.
Yoko Hase Yuuki Mitsutsuji Masayoshi Ishikawa Katsuhiro Maeda Dr. Kento Okoshi Dr. Eiji Yashima Prof. Dr. 《化学:亚洲杂志》2007,2(6):755-763
The achiral sodium salt of poly(4‐carboxyphenyl isocyanide) (poly‐ 1 –Na) folds into a one‐handed helix induced by optically active amines in water. The induced helicity remains when the optically active amines are completely removed, and further modification of the side groups to amide residues is possible without loss of memory of macromolecular helicity. Although the helical poly‐ 1 –Na loses its chiral memory at high temperature, helical polyisocyanides modified with achiral primary amines, which no longer have any chiral components, keep their memory perfectly even at 100 °C in N,N‐dimethylformamide in some cases and exhibit cholesteric liquid‐crystalline phases, thus providing a robust scaffold with heat resistance to which a variety of functional groups can be introduced. 相似文献
116.
The classical trajectory method is used to investigate the unimolecular dynamics of ethyl radical dissociation. It is found that chaotic trajectories need not be backward integrable to yield accurate lifetime, and product energy and angular momenta distributions. This allows the use of large numerical integration step sizes in trajectory calculations. The product energy and angular momenta distributions are independent of the ethyl radical lifetime, and are obtained after only 50 dissociation events. Differences between classical and quantal unimolecular dynamics are discussed, and a prognosis for future trajectory studies of large-molecule unimolecular decompositions is given. 相似文献
117.
Yoshiyuki Hase 《Monatshefte für Chemie / Chemical Monthly》1982,113(4):409-413
The infrared spectra, in the 700–200 cm–1 region, have been reported for6LiHCO2 · H2O,6LiHCO2 · D2O,7LiHCO2 · H2O and7LiHCO2 · D2O and the observed fundamental bands have been discussed taking into account the6Li/7Li and H2O/D2O isotope wavenumber shifts on the fundamental vibrations.
Infrarotspektren (700–200 cm–1) und6Li/7Li- und H2O/D2O-Isotopeneffekte für vier isotopensubstituierte Lithiumformat-monohydrate
Zusammenfassung Die Infrarotspektren in der Region von 700–200 cm–1 werden für6LiHCO2 · H2O,6LiHCO2 · D2O,7LiHCO2 · H2O und7LiHCO2 · D2O angegeben und die beobachteten Grundschwingungen zusammen mit den isotopischen Verschiebungen der Wellenzahlen diskutiert.相似文献
118.
119.
120.
Raffaelli B Pohjoispää M Hase T Cardin CJ Gan Y Wähälä K 《Organic & biomolecular chemistry》2008,6(14):2619-2627
Various conflicting data on the rearrangement and absolute stereochemistry of hydroxylignano-9,7'-lactones are resolved using 18O labeled compounds, also confirmed by an X-ray analysis of a pure lignano-9,7'-lactone enantiomer, obtained for the first time. Under NaH/DMF rearrangement conditions a silyl protected hydroxylignano-9,9'-lactone underwent an unexpected silyl migration. 相似文献