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11.
Isotope shifts have been measured in Sm II from which the shifts between pure configurations 4f 6 s and 4f 65d can be determined. The specific mass shift for such a “transition” was estimated to be (?1±2)mK for a change of two neutrons. The values derived for the change in the nuclear charge distribution,δ〈r 2〉, are in good agreement with the results obtained from isotope shift measurements in Sm I (H. Brand et al.: J. Phys. B11, L99, 1978). The weighted mean values representing the best information onδ〈r 2〉 presently available are in fm2: [144, 148] 0.488(23); [148, 150] 0.285(14); [150, 152] 0.400(19); [152, 154] 0.217(11). 相似文献
12.
Manqi Ruan Hang Zhao Gang Li Chengdong Fu Zhigang Wang Xinchou Lou Dan Yu Vincent Boudry Henri Videau Vladislav Balagura Jean-Claude Brient Peizhu Lai Chia-Ming Kuo Bo Liu Fenfen An Chunhui Chen Soeren Prell Bo Li Imad Laketineh 《The European Physical Journal C - Particles and Fields》2018,78(5):426
After the Higgs discovery, precise measurements of the Higgs properties and the electroweak observables become vital for the experimental particle physics. A powerful Higgs/Z factory, the Circular Electron Positron Collider (CEPC) is proposed. The Particle Flow oriented detector design is proposed to the CEPC and a Particle Flow algorithm, Arbor is optimized accordingly. We summarize the physics object reconstruction performance of the Particle Flow oriented detector design with Arbor algorithm and conclude that this combination fulfills the physics requirement of CEPC. 相似文献
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Melissa M. Cadelis Soeren Geese Benedict B. Uy Daniel R. Mulholland Shara J. van de Pas Alex Grey Bevan S. Weir Brent R. Copp Siouxsie Wiles 《Molecules (Basel, Switzerland)》2021,26(4)
Antimicrobial bioassay-guided fractionation of the endophytic fungi Neofusicoccum australe led to the isolation of a new unsymmetrical naphthoquinone dimer, neofusnaphthoquinone B (1), along with four known natural products (2–5). Structure elucidation was conducted by nuclear magnetic resonance (NMR) spectroscopic methods, and the antimicrobial activity of all the natural products was investigated, revealing 1 to be moderately active towards methicillin-resistant Staphylococcus aureus (MRSA) with a minimum inhibitory concentration (MIC) of 16 µg/mL. 相似文献
15.
Melissa M. Cadelis Natasha S. L. Nipper Alex Grey Soeren Geese Shara J. van de Pas Bevan S. Weir Brent R. Copp Siouxsie Wiles 《Molecules (Basel, Switzerland)》2022,27(1)
Screening of several fungi from the New Zealand International Collection of Microorganisms from Plants identified two strains of Penicillium, P. bissettii and P. glabrum, which exhibited antimicrobial activity against Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus. Further investigation into the natural products of the fungi, through extraction and fractionation, led to the isolation of five known polyketide metabolites, penicillic acid (1), citromycetin (2), penialdin A (3), penialdin F (4), and myxotrichin B (5). Semi-synthetic derivatization of 1 led to the discovery of a novel dihydro (1a) derivative that provided evidence for the existence of the much-speculated open-chained form of 1. Upon investigation of the antimicrobial activities of the natural products and derivatives, both penicillic acid (1) and penialdin F (4) were found to inhibit the growth of Methicillin-resistant S. aureus. Penialdin F (4) was also found to have some inhibitory activity against Mycobacterium abscessus and M. marinum along with citromycetin (2). 相似文献
16.
Edgar Baumeister Heinz Oberhammer Heinar Schmidt Ralf Steudel 《Heteroatom Chemistry》1991,2(6):633-641
The vapor phase structure of (CH3O)2S [1] has been investigated by electron diffraction and ab initio MO calculations, which both result in a C2 symmetry for the most stable geometry, the Cs conformer being less stable by about 12 kJ/mol. The torsional barrier for rotation about one SO bond was calculated as 37 kJ/mol (trans barrier). The geometrical parameters (electron diffraction) of the C2 conformer are: dSO = 162.5(2), dCO = 142.6(3), dCH = 110.5(7) pm angles OSO = 103(1)°, SOC = 115.9(4)°, HCH = 109(1)°, torsional angle COSO = 84(3)°. Geometrical data calculated with 6-31G* basis set agree well with the diffraction data; calculated dipole moments 1.1 D (C2) and 3.3 D (Cs). The infrared spectrum of gaseous (CH3O)2S and the Raman spectra of liquid and solid (CH3O)2S are reported and have been almost fully assigned to the 27 fundamental vibrations. 相似文献
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G. Nöldeke A. Steudel K. E. Wallach H. Walther 《Zeitschrift für Physik A Hadrons and Nuclei》1962,170(1):22-25
Using three different samples of Os192, Os190 and Os186 enriched to 98.68%, 95.46%, and 61.27%, respectively, the isotopic shiftsΔν(Os192?Os190) andΔν(Os192?Os186) have been measured in four Os I-lines with a recording Fabry-Perot spectrometer. The relative isotopic position of Os186 has been found to be
$$\frac{{\Delta \nu (Os^{192} - Os^{186} )}}{{\Delta \nu (Os^{192} - Os^{190} )}} = 3.52 \pm 0.03.$$ 相似文献
19.
U. Brinkmann J. Goschler A. Steudel H. Walther 《Zeitschrift für Physik A Hadrons and Nuclei》1969,228(4):427-439
An atomic beam source for atoms in metastable states is described. The source was used to produce metastable Ca and Sr atoms in the3 P 0,1,2 and1 D 2 and Mg atoms in the3 P 0,1,2 states. The population of these levels was high enough (about 30% of the atoms were in the3 P levels and 3% in the1 D 2 level) so that zero field level crossing experiments could be performed at highly excited levels which were populated by an optical excitation starting from the metastable states. The lifetime results obtained for Ca areτ(4s 4d 3 D 1)=(1.21±0.07)·10?8sec,τ(4s 4f1 F 3)=(2.84±0.23)· 10?8sec, andτ(3d 4p 1 F 3)=(6.15±0.62)·10?8 sec. The three lifetimes have been evaluated using theg J values forLS-coupling. The quoted uncertainties include the errors by a possible deviation fromLS-coupling. 相似文献
20.