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61.
De Schutter DP Saison D Delvaux F Derdelinckx G Rock JM Neven H Delvaux FR 《Journal of chromatography. A》2008,1179(2):75-80
The aim of this study was to create a simple, solventless technique without derivatisation in order to analyze a broad range of volatiles in beer wort. A method was developed using headspace solid-phase microextraction coupled with gas chromatography and mass spectrometry. The procedure was optimised by selection of the appropriate fibre and optimisation of extraction temperature, extraction time, and salting-out. The detection limits were well below the actual wort concentrations of the selected volatiles, ranging from 12 ng/l for linalool to 0.53 microg/l for furfural. Moreover, the procedure showed a good linearity and was applied to the analysis of wort samples taken from a wort boiling process in an industrial brewery. 相似文献
62.
This article presents extensions of the Cramér-Wold theorem to measures that may have infinite mass near the origin. Corresponding
results for sequences of measures are presented together with examples showing that the assumptions imposed are sharp. The
extensions build on a number of results and methods concerned with injectivity properties of the Radon transform. Using a
few tools from distribution theory and Fourier analysis we show that the presented injectivity results for the Radon transform
lead to Cramér-Wold type results for measures. One purpose of this article is to contribute to making known to probabilists
interesting results for the Radon transform that have been developed essentially during the 1980s and 1990s. 相似文献
63.
Tomáš Řezníček Libor Dostál Aleš Růžička Jiří Kulhánek Filip Bureš Roman Jambor 《应用有机金属化学》2011,25(3):173-179
The phosphines L1PPh2 (1) and L2PPh2 (2) containing different Y,C,Y‐chelating ligands, L1 = 2,6‐(tBuOCH2)2C6H3? and L2 = 2,6‐(Me2NCH2)2C6H3?, were treated with PdCl2 and di‐µ‐chloro‐bis[2‐[(N,N‐dimethylamino)methyl]phenyl‐C,N]‐dipalladium(II) and yielded complexes trans‐{[2,6‐(tBuOCH2)2C6H3]PPh2}2PdCl2 (3), {[2,6‐(Me2NCH2)2C6H3]PPh2} PdCl2 (4), {[2,6‐(tBuOCH2)2C6H3]PPh2}Pd(Cl)[2‐(Me2NCH2)C6H4] (5) and {[2,6‐(Me2NCH2)2C6H3]PPh2}Pd(Cl)[2‐(Me2NCH2)C6H4] (6) as the result of different ability of starting phosphines 1 and 2 to complex PdCl2. Compounds 3–6 were characterized by 1H, 13C, 31P NMR spectroscopy and ESI‐MS. The molecular structures of 3,4 and 6 were also determined by X‐ray diffraction analysis. The catalytic activity of complexes 3–6 was evaluated in the Suzuki‐Miyaura cross‐coupling reaction. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
64.
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66.
Air-coupled ultrasound (ACU) provides a tool to evaluate wood samples of small or moderate thickness (<30 mm) thereby avoiding direct contact or liquid coupling. Results of through-transmission ACU measurements on wood veneer samples and related products are reported with respect to a wide variety of quality aspects. Fluctuations in the averaged received signal levels appear to be correlated to the presence of natural or machine-induced thickness and density variations, flaws and grain damage, errors produced by the manufacturing process, insufficient bonding on a substrate, etc. In addition it is seen that the variability of the signal levels enables to distinguish between quarter and crown areas. 相似文献
67.
68.
Filip Cuyckens Rob Hurkmans Jose M. Castro‐Perez Laurent Leclercq Russell J. Mortishire‐Smith 《Rapid communications in mass spectrometry : RCM》2009,23(2):327-332
Mass defect, neutral loss and isotope filtration techniques were applied to electrospray ionization mass spectrometry (ESI‐MS) data obtained for in vivo and in vitro samples of drug metabolism studies. A combination of these post‐acquisition processing techniques was shown to be more powerful than the use of one of these tools alone for the detection in complex matrices of metabolites of candidate drugs with a characteristic isotope pattern (e.g. containing bromine, chlorine, or a high proportion of radiolabeled drug (12C/14C)) or characteristic neutral losses. In combination with ‘all‐in‐one’ data acquisition this methodology is able to perform software‐driven constant neutral loss scanning for an unlimited number of mass differences at any time after analysis. Highly selective MS chromatograms were obtained with excellent correlation with their corresponding radiochromatograms. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
69.
Jarmo Lohilahti Herkko Mattila Filip Paw?owski 《Journal of Molecular Spectroscopy》2005,234(2):279-285
The ground state spectrum of the formaldehyde D213CO molecule in the range from 25 to 360 cm−1 has been recorded by a Fourier transform infrared spectrometer. The quantum number limits of the assigned transitions are J = 6-54 and Ka = 0-16. The data was fitted into Watson’s A- and S-reduced Hamiltonians in Ir-representation up to eighth order. The determinable constants calculated from both reductions are compared. The standard deviation of the far infrared data is 3.0 MHz. The spectroscopic constants are also calculated to high accuracy at the CCSD(T)/cc-pVQZ level of ab initio theory and agree well with the experimental ones. 相似文献
70.
Aleksander Filip Żarnecki 《Pramana》2007,69(5):937-941
The CAIN simulation program was used to study the outgoing beam profile for the photon collider at ILC. The main aim of the
analysis was to verify the feasibility of the photon linear collider running with 20 mrad electron beam crossing angle. The
main problem is the distorted electron beam, which has to be removed from the interaction region. It is shown that with a
new design of the final dipole, it should be possible to avoid large energy losses at the face of the magnet.
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