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Abstract Under a suitable ellipticity condition, we show that classical SG-pseudodifferential operators of nonnegative order possess
complex powers. We show that the powers are again classical and derive an explicit formula for all homogeneous components.
Keywords: Complex power, Weighted symbols, Noncompact manifolds 相似文献
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Linda Kaufmann Hans‐Wolfram Lerner Michael Bolte 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(10):o588-o590
A new polymorph of tetraphenyldiboroxane [or oxybis(diphenylborane)], C24H20B2O, (Ia), has been found. It is monoclinic, like the already known form, (Ib), and can be refined in the same space group, namely P21/c, or in the equivalent setting P21/n. The molecular conformations of the two polymorphs differ in the rotations of two of the phenyl rings about the B—C bonds, leading to markedly different packing patterns and cell dimensions. 相似文献
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J. Brunner H. -J. Grabosch H. H. Kaufmann R. Nahnhauer S. Nowak S. Schlenstedt V. V. Ammosov V. I. Ermolaev A. A. Ivanilov P. V. Ivanov V. I. Konyushko V. M. Korablev V. A. Korotkov V. A. Krupnov V. V. Makeev A. G. Myagkov A. Yu. Polyarush A. A. Sokolov SKAT-Collaboration 《Zeitschrift fur Physik C Particles and Fields》1990,45(4):551-555
The cross sections of neutrino and antineutrino quasielastic reactions \(vn \to \mu ^ - p,\bar vp \to \mu ^ + n,\bar vp \to \mu ^ + \Lambda\) were studied in the neutrino energy range between 3 and 30 GeV. In comparison withV-A theory axial mass parameters ofM A =(1.06±0.05±0.14) GeV/c2 from neutrino andM A =(0.71±0.10±0.20) GeV/c2 from antineutrino data were found. The total cross-section for the hyperon production process can be described byM A =1.0 GeV/c2. 相似文献
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V. V. Ammosov V. I. Ermolaev V. S. Filippov V. I. Hleborad A. A. Ivanilov P. V. Ivanov V. I. Konyushko V. M. Korablev V. A. Korotkov V. A. Krupnov A. I. Kurnosenko E. P. Kuznetsov V. V. Makeev A. G. Myagkov A. Yu. Polyarush A. A. Sokolov H. J. Grabosch H. H. Kaufmann R. Nahnhauer S. Nowak H. E. Roloff S. Schlenstedt SKAT-Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,40(4):493-496
We present the final results from the search for μe pairs produced in neutrino interactions using the freon filled bubble chamber SKAT. The rate of μ? e + pairs to charged current events above the charm threshold is \(R_{\mu ^ - e^ + } = (4.8 \pm 1.1)10^{ - 3} \) . Assuming charm particle production to be the origin of the positron we calculate \(R_{\Lambda _c^ + } = (6.2 \pm 3.1)10^{ - 2} \) andR D =(2.8±0.9)10?2. We observe no considerable μ? e ? pair production above the background. In the regionE v >3 GeV,p μ,e >1.0 GeV/c andp μ>p e we find with a 90% confidence level the limit \(R_{\mu ^ - e^ - }< 1.7 10^{ - 4} \) . 相似文献
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Determination of 11 aminoglycosides in meat and liver by liquid chromatography with tandem mass spectrometry 总被引:2,自引:0,他引:2
A method using liquid chromatography with tandem mass spectrometry was developed for the determination of 11 commonly used aminoglycoside antibiotics in meat. The proposed method is sufficiently sensitive (detection limits of 15 to 40 ppb for the various antibiotics) and highly selective. It is suitable for the quantitation and confirmation of aminoglycosides in a variety of matrixes (pork muscle, fish, and veal liver). Any multiresidue method for aminoglycosides must take into account their high affinity toward sample proteins and the significantly different pK values of the various analytes. The developed method uses a low-pH extraction with trichloracetic acid to ensure complete extraction of the analytes from the matrix. An anion-exchange step is used to remove the acid from the centrifuged extract. Aminoglycosides in this solution of low ionic strength can be quantitatively retained and afterwards eluted from a weak cation-exchanger solid-phase extraction (SPE) cartridge. The highly selective SPE steps produce clean extracts, which minimize possible suppression of the mass spectrometer signal. 相似文献
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Formation and Crystal Structure of an Oxygen Bridged Titanium Amino Bisphenoxide Di‐(μ‐oxo)‐titan‐bis[aminobisphenoxide] ( 3 ) was obtained by reaction of (i‐Prop)2TiL* ( 2 ) {L* = O‐4, 6‐(t‐Bu)2C6H2‐2‐CH2‐[1, 4‐N2C5H10]‐2'‐CH2‐4', 6'‐(t‐Bu)2C6H2O] with water in a molar ratio 1:1 in diethylether. Both i‐Propyl moieties are substituted yielding the dimeric oxygen bridged amino bisphenoxide complex. The six coordinate Ti atoms are a result of Ti—N and Ti—O interactions of the corresponding atoms of the amino bisphenoxide ligand and the bridging O atoms. The central planar Ti2O2 ring may be considered as the general structural feature of the title compound: Space group P1¯, Z = 1, lattice dimensions at —60°C: a = 11.6899(4), b = 11.7873(4), c = 12.6462(4) Å, α = 98.070(1), β = 99.660(1), γ = 95.343(1)°, R1 = 0.0469, wR2 = 0.1049, GooF = 0.939. 相似文献