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161.
Antioxidant and prooxidant effects of nitric oxide (NO) on lipid peroxidation in aqueous and non-aqueous media were examined. In an aqueous solution, NO did not induce peroxidation of unoxidized methyl linoleate (ML) and suppressed the radical initiator-induced oxidation of ML. NO suppressed the Fe(II) ion-induced oxidation of mouse liver microsomes. NO reduced the O2 consumption during the radical initiator-induced oxidation of linoleic acid in an aqueous medium. NO conversion into NO2- in an aqueous medium was not affected by unoxidized ML and was slightly reduced by peroxidizing ML. On the other hand, as well as pure NO2, NO induced peroxidation of unoxidized ML in n-hexane in a dose-dependent fashion. NO did not suppress the radical initiator-induced oxidation of ML in n-hexane. Nitrogen oxide species (NO2 or N2O3) formed by autoxidation was dramatically lost in n-hexane in the presence of unoxidized ML. The results indicated that NO terminated lipid peroxidation in an aqueous medium, whereas NO induced lipid peroxidatiton in a non-aqueous medium. Hence, NO showed both antioxidant and prooxidant effects on lipid peroxidation depending on the solvents. 相似文献
162.
In this paper, we construct a non-toral compact complex parallelizable pseudo-Kähler solvmanifold.pseudo-Kähler, complex-parallelizable manifold, compact solvmanifold, Borel–Remmert theorem.Mathematics Subject Classiffications (2000). 53C15, 53D05 相似文献
163.
Takumi Maeda Keiichi Kimura Toshiyuki Shono 《Fresenius' Journal of Analytical Chemistry》1982,313(5):407-410
Summary Solvent extraction of alkaline earth metal picrates with poly- and bis(crown ether)s containing benzo-15-crown-5- and benzo-18-crown-6 moieties was carried out in a water-chloroform system. The poly- and bis(crown ether)s showed larger extractability for the metal picrates than the corresponding monocyclic crown ethers. Especially, poly- and bis(benzo-15-crown-5), and bis(benzo-18-crown-6) were found to have relatively high extractability and selectivity for Ba2+ and Sr2+, respectively.
Lösungsmittelextraktion von Erdalkalipikraten mit Hilfe von Poly- und Bis-Kronenethern
Zusammenfassung Poly- und Bis-Kronenether mit Benzo-15-krone-5- und Benzo-18-krone-6-Einheiten wurden zur Extraktion von Erdalkalipikraten im Wasser-Chloroform-System verwendet. Die genannten Ether zeigten eine bessere Extraktionsfähigkeit für die Pikrate als die entsprechenden monocyclischen Kronenether. Im Falle von Ba2+ und Sr2+ ergab sich eine besonders gute Extrahierbarkeit und Selektivität mit Poly- und Bis(benzo-15-krone-5)- und Bis(benzo-18-krone-6)-Ethern.相似文献
164.
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166.
Takumi Nakamura Kazuma Ban Dr. Yasushi Yoshida Prof. Dr. Takashi Mino Prof. Dr. Yoshio Kasashima Prof. Dr. Masami Sakamoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(66):16338-16341
Asymmetric synthesis was performed by combining the photochemical reaction of an achiral substrate followed by crystallization-induced deracemization. The results indicated that a fused indoline produced by photochemical intramolecular δ-hydrogen abstraction and cyclization of N-(5-chloro-2-methylphenyl)phthalimide crystallized as a racemic conglomerate. Since this substrate has an aminal skeleton, racemization involving a ring-opening and ring-closing equilibrium process occurred under suitable conditions. Efficient racemization was observed in acetone containing a catalytic base, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). Crystallization-induced dynamic deracemization by Viedma ripening from racemic indoline was performed with an excellent enantioselectivity of 99 % ee. Furthermore, one-pot asymmetric synthesis of the indoline was achieved by the photochemical reaction of achiral phthalimide followed by continuous attrition-enhanced deracemization converging to 99 % ee of enantiomeric crystals. This is the first example of asymmetric expression and amplification by photochemical hydrogen abstraction and crystallization-induced dynamic deracemization. 相似文献
167.
Maurizio Corradini Masaki Hori Takumi Kobayashi Marco Leali Evandro Lodi-Rizzini Valerio Mascagna Aldo Mozzanica Michela Prest Anna Soter Koichi Todoroki Erik Vallazza Luca Venturelli Nicola Zurlo 《Hyperfine Interactions》2012,213(1-3):31-39
The results of the annihilation cross sections measurement of 5.3 MeV antiprotons on nickel, tin, platinum and Mylar targets performed by the ASACUSA Collaboration at CERN are presented and compared with the existing data and models. From the experimental point of view the presented data are the first measurement of antinucleon annihilation cross sections at low energies obtained with a pulsed beam. This results open the road for the next measurements at the very low energies of the order of 100 keV that are in progress by the ASACUSA Collaboration. The experimental method foreseen for the 100 keV measurement is illustrated. 相似文献
168.
Toward Naphthocyclinones: Doubly Connected Octaketide Dimers with a Bicyclo[3.2.1]octadienone Core by Thiolate‐Mediated Cyclization
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Dr. Yoshio Ando Subaru Hori Takumi Fukazawa Prof. Dr. Ken Ohmori Prof. Dr. Keisuke Suzuki 《Angewandte Chemie (International ed. in English)》2015,54(33):9650-9653
A viable method is reported for the synthesis of the bicyclo[3.2.1]octadienone scaffold in naturally occurring octaketide dimers. The procedure employs a reductive cyclization reaction mediated by an unusual ethanedithiol monosodium salt. 相似文献
169.
Takumi Yokota 《Mathematische Zeitschrift》2014,277(1-2):293-304
It was proved by F. Wilhelm that Gromov’s filling radius of closed positively curved manifolds with a uniform lower bound on sectional curvature attains the maximum with the round sphere. Recently the author proved that this is also the case for closed finite-dimensional Alexandrov spaces with a positive lower curvature bound. These were proved as a corollary of a comparison theorem for the invariant called spread of those spaces. In this paper, we extend the latter result to infinite-dimensional Alexandrov spaces. 相似文献
170.
We describe here a Tf?NH-catalyzed formal (3+3) cycloaddition of silyl enol ethers with acrylates as a new domino reaction. In the domino sequence, the catalyst activates Michael addition, deprotonation of the resulting silyloxonium cation and intramolecular Claisen condensation. It was found that reaction modes significantly depend on the reaction temperature. We also examined the mechanistic detail of the reaction by 1H-NMR experiment. 相似文献