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71.
G. Alexander L. Criegee H.C. Dehne K. Derikum R. Devenish G. Flügge G. Franke Ch. Gerke E. Hackmack P. Harms G. Horlitz Th. Kahl G. Knies E. Lehmann R. Schmitz R.L. Thompson U. Timm K. Wacker 《Physics letters. [Part B]》1978,76(5):652-656
The polarization of the f0(1270) and ?0(770) produced in the J/ψ decays into f0γ and ?0π0 are measured in e+e? collisions at 3.1 GeV. A fit to the f0 production and decay angular distributions yields the values A1/A0 = 0.6 ± 0.3 and A2/A0 = 0.3 ?1.6+0.6, where Aλ are the f0 helicity amplitudes. These results are in good agreement with the values predicted from a QCD two-gluon-exchange model. In addition an upper limit of 2.3 × 10?4 is obtained for the J/ψ → f′0(1514) γ decay branching ratio which implies Γ(J/ψ → f′γ)/Γ(J/ψ → f0γ) ? 0.12 ± 0.05. 相似文献
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J. Harms G. Jander J. Wierciski R. Ammon K. Hinsberg und J. Courtois 《Fresenius' Journal of Analytical Chemistry》1937,111(1):30-34
Ohne Zusammenfassung 相似文献
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Amido Ligands for the Synthesis of Polynuclear Lanthanoid Complexes By 1 : 1 reaction of LnBr3 with NaNHPh in THF the Rare-Earth Complexes [Ln2Br4(μ2-NHPh)2(thf)5] (Ln = Sm ( 1 ), Ln = Gd ( 2 )) with two bridging anilido ligands are obtained. In the system LnBr3/NaNHPh/(Me2SiO)3 the tetranuclear compounds [Ln4(μ4-O)(NHPh)3(OSiMe2NPh)6Na5(thf)7] · THF (Ln = Gd ( 3 ), Ln = Yb ( 4 )) can be built up. They have a central μ4-oxygene atom in the Ln4-tetrahedron. It has an oxa-dimethylsilyl-N-phenylamido ligand over all edges and an anilido ligand on three vertexes. By this reaction small amount of [Na4(thf)6Yb2(OSiMe2NPhSiMe2O)2(OSiMe2NPh)2(NHPh)2] ( 5 ) with a O- and N-bridged Yb–Na polyhedron and N-phenyl-bis(dimethylsilanolato)-ligands coordinating μ2-η2 with its oxygen atoms are obtained. Reaction of Lanthanideshalides with LiNHtBu leads to dimeric complexes. The formation of bridging oxasilylamido ligands is also observed. The compound [Li2Ln(OSiMe2NtBu)2(HNtBu)(thf)]2 (Ln=Sm ( 6 ), Gd ( 7 ) and Yb ( 8 )) contains now an O- and N-bridged Ln–Li polyhedron. (Crystal Data of 1–8 see ‘‘Inhaltsverzeichnis”︁”︁). 相似文献
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Sabine Schlecht Dirk V. Deubel Gernot Frenking Gertraud Geiseler Klaus Harms Jrg Magull Kurt Dehnicke 《无机化学与普通化学杂志》1999,625(6):887-891
Phosphoraneiminato Complexes of Rhenium(VII). Syntheses and Crystal Structures of [ReO3(NPR3)] (R = Ph, Et) and of [ReO(OSiMe3)3(Me3SiNPEt3)] The phosphoraneiminato complexes [ReO3(NPR3)] with R = Ph ( 1 ) and R = Et ( 2 ) are made from dirhenium heptaoxide and the silylated phosphoraneimines Me3SiNPR3. The complexes 1 and 2 as well as the red silanolate [ReO(OSiMe3)3(Me3SiNPEt3)] ( 3 ), which is formed as a by‐product in the synthesis of 2 , are characterized crystallographically. 1 and 2 are monomeric molecules, in which the phosphoraneiminato ligands NPR3– realize short ReN bonds of 179.3 pm ( 1 ) and 178.6 pm ( 2 ), respectively, with large ReNP bond angles of 162.0° ( 1 ) and 160.6° ( 2 ), respectively. In the rhenium(V) complex 3 the oxoligand occupies the apical position of the tetragonal pyramidal coordination of the rhenium atom, while the oxygen atoms of the Me3SiO– groups take the basic positions along with the nitrogen atom of the phosphaneimine molecule. 相似文献
78.
Ulrike Riese Naim Faza Werner Massa Klaus Harms Thees Breyhan Paul Knochel Jürgen Ensling Vadim Ksenofontov Philipp Gütlich Kurt Dehnicke 《无机化学与普通化学杂志》1999,625(9):1494-1499
The phosphoraneiminato complexes [MnBr(NPEt3)]4 ( 1 ) and [M4Br5{NP(NMe2)3}3] with M = Mn ( 2 ) and M = Co ( 3 ) are prepared by melting reactions from the anhydrous metal dibromides with the silylated phosphaneimines Me3SiNPR3 (R = Et, NMe2) in the presence of potassium fluoride. All complexes are characterized by crystal structure analyses. 1 forms an only slightly distorted Mn4N4 heterocubane skeleton with an approximate Td symmetry and short Mn…Mn distances of average 295.7 pm. In the structures of 2 and 3 one μ3-NPEt3 ligand of 1 is replaced by one bromine atom with μ3-function. This leads to the novel heterocubane type M4N3Br with approximate C3 symmetry. The deformation of the cubic skeleton leads to metal-metal distances of different lengths, i. e. 292.7 and 323.6 pm in 2 and 274.4 and 306.2 pm in 3 . Temperature dependent magnetic susceptibility measurements between 300 and 5 K on 1 have shown that strong antiferromagnetic coupling exists between the Mn(II) ions with S = 5/2, with a large negative Weiss constant of Θ = –694 K. 相似文献
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