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21.
Uwe Franken 《Mathematische Nachrichten》1993,164(1):119-139
For a weight function ω and a closed set A ? ?N let ?(ω)(A) denote the space of all ω-Whitney jets of Beurling type on A. It is shown that for each closed set A ? ?N there exists an ω-extension operator EA: ?(ω)(A) → ?(ω)(?N) if and only if ω is a (DN)-function (see MEISE and TAYLOR [18], 3.3). Moreover for a fixed compact set K ? ?N there exists an ω-extension operator EK: ?(ω)(K) → ?(ω)(?N) if and only if the Fréchet space ?(ω)(K) satisfies the property (DN) (see Vogt [29], 1.1.). 相似文献
22.
Edwin Weber George R. Newkome Frank R. Fronczek Sybille Franken 《Journal of inclusion phenomena and macrocyclic chemistry》1988,6(1):1-7
Crown amide (1) forms a stoicheiometric 1:1 inclusion complex with water, the X-ray crystal structure of which is reported. Crystals of1 · H2O are triclinic, space groupP1, witha=7.503(1),b=11.394(3),c=13.443(2) Å, =107.066(18), =96.627(10), =106.377(14)°, andZ=2.R
F
=0.039 for 1697 MoK reflections [I>3(I)] measured at 24°C. The structure features a hydrogen bonded hostguest relationship with concrete1 · H2O units. Hydrogen bonds are between the water oxygen and O(4), N(4), respectively. The crystal packing shows a cavity arrangement of four ligands around each water molecule.
Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82055 (16 pages). 相似文献
23.
The sinusoidal profile decay technique for measuring surface self-diffusion was extended to profile amplitudes as low as 50 Å. The advantages of the new technique are: small curvature, low step densities, nearly constant surface free energy over the orientational range of the profile, extended lower limit on profile periodicity and hence greater sensitivity. The new technique was applied to measurements on Ni(110) crystals. 相似文献
24.
Frederik Rombouts Dennis Franken Mirielle Braeken Jinsheng Chen 《Tetrahedron letters》2010,51(37):4815-2879
A new and facile microwave-assisted protocol for the debenzylation of N-benzylamides with triflic acid has been developed. Both secondary and tertiary aliphatic or aromatic amides are obtained in moderate to good yields. 相似文献
25.
Melanie Gldner Brbel Geniffke Andreas Franken Keith S. Murray Heiner Homborg 《无机化学与普通化学杂志》2001,627(5):935-947
Mononitrosyl and trans ‐Dinitrosyl Complexes of Phthalocyaninates of Manganese and Rhenium Tetra(n‐butyl)ammonium or di(triphenylphosphane)iminium nitrosylacidophthalocyaninato(2–)manganate, (cat)[Mn(NO)(X)pc2–] (X = ONO, NCO, N3; cat = nBu4N, PNP) is prepared from acidophthalocyaninato(2–)manganese, [Mn(X)pc2–], (cat)NO2 and (nBu4N)BH4 in CH2Cl2 or from nitrosylphthalocyaninato(2–)manganese, [Mn(NO)pc2–] and (nBu4N)X (X = ONO, NCO, N3, NCS) at T < 120 °C, respectively. [Mn(NO)(X)pc2–]– dissociates in methanol, and [Mn(NO)pc2–] precipitates. Nitrito(O)phthalocyaninato(2–)manganese, (cat)NO2 and hydrogensulfide yield trans‐di(nitrosyl)phthalocyaninato(2–)manganate, trans[Mn(NO)2pc2–]–, isolated as red violet (PNP) and (nBu4N) complex salt. Nitrosyl(triphenylphosphane oxide)phthalocyaninato(2–)manganese, [Mn(NO)(OPPh3)pc2–] is obtained by addition of OPPh3 to [Mn(NO)pc2–] at 200 °C. Di(triphenylphosphane)phthalocyaninato(2–)rhenium(II) and (PNP)NO2 in CH2Cl2 or in molten (PNP)NO2 and PPh3 at 100 °C yields green blue l‐di(triphenylphosphane)iminium nitrosylnitrito(O)phthalocyaninato(2–)rhenate, l(PNP)[Re(NO)(ONO)pc2–]. Similarly, but with (nBu4N)NO2 red plates of tetra‐(n‐butyl)ammonium trans‐di(nitrosyl)phthalocyaninato(2–)rhenate, (nBu4N)trans[Re(NO)2pc2–] is isolated. Addition of (PNP)Br or (PNP)PF6 to a concentrated solution of (nBu4N)trans[Re(NO)2pc2–] in pyridine precipitates l(PNP)trans[Re(NO)2pc2–]. (nBu4N)trans[Re(NO)2pc2–] and PPh3 at 300 °C yield blue green nitrosyl(triphenylphosphane oxide)phthalocyaninato(2–)‐ rhenium, [Re(NO)(OPPh3)pc2–], that is oxidised with iodine precipitating nitrosyl(triphenylphosphane oxide)phthalocyaninato(2–)rhenium triiodide, [Re(NO)(OPPh3)pc2–]I3. The crystal structures of l(PNP)[Mn(NO)(ONO)pc2–] ( 1 ), l(PNP)‐ [Mn(NO)(NCO)pc2–] ( 2 ), l(PNP)trans[Mn(NO)2pc2–] ( 3 ), l(PNP)trans[Re(NO)2pc2–] ( 4 ) [Mn(NO)(OPPh3)pc2–] ( 5 ), [Re(NO)(OPPh3)pc2–] ( 6 ), and [Re(NO)(OPPh3)pc2–]I3 · CH2Cl2 ( 7 ) have been determined. The M–N(NO) distance varies between 1.623(12) Å in 5 and 1.846(3) Å in 3 . The M–N–O moiety is almost linear. The UV‐Vis spectra with the B band at ca. 14500 cm–1and the Q band at 30400 cm–1 do not dependent significantly on the axial ligand and the metal atom and its oxidation state. N–O stretching vibrations are observed in the IR spectra between 1701 cm–1 in 3 and 1753 cm–1 in [Mn(NO)pc2–] or for the Re series between 1571 cm–1 in 4 and 1724 cm–1 in 7 . M–N(NO) stretching and M–N–O deformation vibrations are assigned in the IR spectra and resonance Raman spectra between 486 cm–1 in 4 and 620 cm–1 in 1 . 相似文献
26.
Background
Classical conditioning has been suggested to play an important role in the development, maintenance, and relapse of tobacco smoking. Several studies have shown that initially neutral stimuli that are directly paired with smoking are able to elicit conditioned responses. However, there have been few human studies that demonstrate the contribution of higher-order conditioning to smoking addiction, although it is assumed that higher-order conditioning predominates learning in the outside world. In the present study a higher-order conditioning task was designed in which brain responses of smokers and non-smokers were conditioned by pairing smoking-related and neutral stimuli (CS1smoke and CS1neutral) with two geometrical figures (CS2smoke and CS2neutral). ERPs were recorded to all CSs. 相似文献27.
Treatment of the 11-vertex carborane anion [closo-2-CB(10)H(11)](-) with Ni(0) reagents in tetrahydrofuran (THF) affords-via oxidative insertion reactions-12-vertex Ni(II) complexes, isolated as the salts [N(PPh(3))(2)][2,2-L(2)-closo-2,1-NiCB(10)H(11)] (L = CO (1a), CNBu(t) (1b), and CNXyl (1c; Xyl = C(6)H(3)Me(2)-2,6); L(2) = cod (1d; cod = 1,2:5,6-eta-cyclo-octa-1,5-diene)). One CO ligand in 1a is readily replaced by donors L' in the presence of Me(3)NO to give the species [N(PPh(3))(2)][2-CO-2-L'-closo-2,1-NiCB(10)H(11)] (L' = PEt(3) (1e), PPh(3) (1f), CNBu(t) (1g), and CNXyl (1h)). The anionic complexes themselves readily react with hydride abstracting reagents in the presence of donor ligands to yield zwitterionic complexes in which boron vertexes bear substituents that are bound through C, N, or O atoms. Thus, for example, 1c with H(+) and CNXyl gives [2,2,7-(CNXyl)(3)-closo-2,1-NiCB(10)H(10)] (2b), while 1f with Me(+) in the presence of OEt(2) affords [2-CO-2,11-{mu-PPh(2)(C(6)H(4)-o)}-7-OEt(2)-closo-2,1-NiCB(10)H(9)] (4), in which an additional cycloboronation of one phosphine phenyl ring has occurred. In contrast, 1f with Me(+) in the presence of NCMe gives a mixture of the isomers [2-CO-2-PPh(3)-7-{(X)-N(Me)=C(H)Me}-closo-2,1-NiCB(10)H(10)] (X identical with E (5c) and Z (5d)). X-ray diffraction analyses of compounds 1a, 2b, 4, and 5c confirmed their important structural features. 相似文献
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