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71.
Zusammenfassung 1,3-Dicarbonylverbindungen reagieren mit Kohlensuboxid (C3O2) in Gegenwart katalyt. Mengen konz. H2SO4 zu Derivaten des 4-Hydroxy-2H,5H-pyrano[4,3-b]pyran-2,5-dions. Reaktionsverlauf, Struktur, IR-, UV- undNMR-Spektren werden diskutiert.
Nach einem Vortrag, gehalten anläßlich des Chemikertreffens in Graz am 28.9.1965. 相似文献
1,3-Dicarbonyl compounds react with C3O2 in the presence of catalytic amounts of H2SO4 to derivatives of 4-hydroxy-2H,5H-pyrano[4,3-b]pyran-2,5-dione. The mechanism of the reaction, the structure, IR-, UV- andNMR-spectra are discussed.
Nach einem Vortrag, gehalten anläßlich des Chemikertreffens in Graz am 28.9.1965. 相似文献
72.
Zusammenfassung Durch Einwirkung von SOCl2 auf 4-Hydroxycumarin bzw. 4-Hydroxycarbostyril sind Bis-(4-hydroxycumarinyl-[3])-sulfid (I) und Bis-(4-hydroxycarbostyril-[3])-sulfid (II) leicht zugänglich. Diese Sulfide können zu Dicumarino- bzw. Dicarbostyrilo-(1,4)-oxathiinen (III bzw. IV) cyclisiert werden.
Herrn KollegenH. Bretschneider, Innsbruck, mit den besten Wünschen zum 60. Geburtstag.
Aus der DissertationTh. Kappe, Universität Graz 1961, S. 78–83. 相似文献
Bis-(4-hydroxycoumarinyl-[3])-sulfide (I) and bis-(4-hydroxycarbostyril-[3])-sulfide (II) have been prepared by the reaction between SOCl2 and 4-hydroxycoumarin and 4-hydroxycarbostyril. Cyclisation of these sulfides yielded dicoumarino- (III) and dicarbostyrilo-oxathiin-(1.4) (IV).
Herrn KollegenH. Bretschneider, Innsbruck, mit den besten Wünschen zum 60. Geburtstag.
Aus der DissertationTh. Kappe, Universität Graz 1961, S. 78–83. 相似文献
73.
74.
M. Sc. Yasemin Akbulut Hannah J. Gaunt Prof. Katsuhiko Muraki Dr. Melanie J. Ludlow Dr. Mohamed S. Amer Dr. Alexander Bruns Dr. Naveen S. Vasudev Dr. Lea Radtke Dr. Matthieu Willot M. Sc. Sven Hahn M. Sc. Tobias Seitz Dr. Slava Ziegler Prof. Dr. Mathias Christmann Prof. Dr. David J. Beech Prof. Dr. Herbert Waldmann 《Angewandte Chemie (International ed. in English)》2015,54(12):3787-3791
Current therapies for common types of cancer such as renal cell cancer are often ineffective and unspecific, and novel pharmacological targets and approaches are in high demand. Here we show the unexpected possibility for the rapid and selective killing of renal cancer cells through activation of calcium‐permeable nonselective transient receptor potential canonical (TRPC) calcium channels by the sesquiterpene (?)‐englerin A. This compound was found to be a highly efficient, fast‐acting, potent, selective, and direct stimulator of TRPC4 and TRPC5 channels. TRPC4/5 activation through a high‐affinity extracellular (?)‐englerin A binding site may open up novel opportunities for drug discovery aimed at renal cancer. 相似文献
75.
We are using the coordinating anions tetrakis(imidazolyl)borate and tetrakis(4-methylimidazolyl)borate to construct new metal-organic framework structures. In this report, we are exploring materials similar in composition to the previously reported layered network structure Pb[B(Im)(4)](NO(3))(nH(2)O). The metal in this compound can be replaced with isoelectronic Tl(I), affording Tl[B(Im)(4)], and the borate can be modified by using 4-methylimidazole, resulting in Pb[B(4-MeIm)(4)](NO(3)) and Tl[B(4-MeIm)(4)]. Like the parent Pb[B(Im)(4)](NO(3))(nH(2)O), Tl[B(Im)(4)] and Tl[B(4-MeIm)(4)] are layered network structures but both lack anions or solvent molecules in the interlayer spacing. The material Pb[B(4-MeIm)(4)](NO(3)), however, exhibits a 3D network structure that lacks an open topology, resulting from the increased stereochemical activity (greater steric bulk toward other ligands) of the 4-methylimidazole ring. Both of the Tl(I) solids display longer M-N bonds than observed in the analogous Pb(II) compounds; these lengths account for the decreased effect of the stereochemical activity of the 4-methylimidazole ring in Tl[B(4-MeIm)(4)]. 相似文献
76.
The Crystal Structure of the Hydrated Cyano Complexes NMe4MnII[(Mn, Cr)III(CN)6] · 3 H2O and NMe4Cd[MIII(CN)6] · 3 H2O (MIII = Fe, Co): Compounds Related to Prussian Blue The crystal structures of the isotypic tetragonal compounds (space group I4, Z = 10) NMe4MnII · [(Mn, Cr)III(CN)6] · 3 H2O (a = 1653.2(4), c = 1728.8(6) pm), NMe4Cd[Fe(CN)6] · 3 H2O (a = 1642.7(1), c = 1733.1(1) pm) and NMe4Cd[Co(CN)6] · 3 H2O (a = 1632.1(2), c = 1722.4(3) pm) were determined by X‐rays. They exhibit ⊥ c cyanobridged layers of octahedra [MIII(CN)6] and [MIIN4(OH2)2], which punctually are interconnected also || c to yield altogether a spaceous framework. The MII atoms at the positions linking into the third dimension are only five‐coordinated and form square pyramids [MIIN5] with angles N–MII–N near 104° and distances of Mn–N: 1 × 214, 4 × 219 pm; Cd–N: 1 × 220 resp. 222, 4 × 226 resp. 228 pm. Further details and structural relations within the family of Prussian Blue are reported and discussed. 相似文献
77.
78.
One-bond Pt-Pt nuclear spin-spin coupling constants J(Pt-Pt) for closely related dinuclear Pt complexes can differ by an order of magnitude without any obvious correlation with Pt-Pt distances. As representative examples, the spin-spin couplings of the dinuclear Pt(I) complexes [Pt(2)(CO)(6)](2+) (1) and [Pt(2)(CO)(2)Cl(4)](2-) (2) have been computationally studied with a recently developed relativistic density functional method. The experimental values are (1)J((195)Pt-(195)Pt) = 5250 Hz for 2 but 551 Hz for 1. Many other examples are known in the literature. The experimental trends are well reproduced by the computations and can be explained based on the nature of the ligands that are coordinated to the Pt-Pt fragment. The difference for J(Pt-Pt) of an order of magnitude is caused by a sensitive interplay between the influence of different ligands on the Pt-Pt bond, and relativistic effects on metal-metal and metal-ligand bonds as well as on "atomic orbital contributions" to the nuclear spin-spin coupling constants. The results can be intuitively rationalized with the help of a simple qualitative molecular orbital diagram. 相似文献
79.
We are using the coordinating anion tetrakis(imidazolyl)borate to construct new metal-organic framework structures. In this report, we present three alkaline earth metal network solids incorporating this anion. All three compounds have the same formula, M[B(Im)(4)](2)(H(2)O)(2) (M = Mg, Ca, Sr), and the same coordination environment about the metal. However, the three compounds have different network structures with different degrees of hydrogen bonding; the Mg material forms a two-dimensional network and the Ca and Sr compounds form one-dimensional chains. In addition, we present the structure of the protonated anion B(HIm)(Im)(3) as a model for the default structure of this anion and discuss how the conformation of tetrakis(imidazolyl)borate can affect the structure of network solids. 相似文献
80.