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71.
Fulvio Rossi Fabrizia Fabrizi de Biani Piero Zanello Piotr Buchalski 《Journal of Solid State Electrochemistry》2009,13(10):1505-1510
A collection of nickelocene and cobaltocene analogs with one or two nickelafluorenyl rings has been recently synthesized starting
from 9-nickelafluorenyllithium complex. The redox ability of the whole series of derivates has been investigated by electrochemical
techniques, and the nature of the frontier orbitals responsible for the electron transfer activity of this class of compounds
has been supported by extended Hückel calculations.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
72.
Cavalli S Tipton AR Overhand M Kros A 《Chemical communications (Cambridge, England)》2006,(30):3193-3195
A generic method for the efficient in-situ modification of liposomes is described based on "click" chemistry, and a simple colorimetric assay is developed for monitoring the reaction. 相似文献
73.
Kuritka I Negri F Brancolini G Suess C Salaneck WR Friedlein R 《The journal of physical chemistry. B》2006,110(38):19023-19030
Structural and electronic properties of pristine and lithium-intercalated, phenyl-capped aniline dimers as a model for the lithium-polyaniline system have been studied by photoelectron spectroscopy and quantum chemical calculations. It was found that the electronic structure of reduced and oxidized forms of oligoanilines is only weakly affected by isomerism. Upon intercalation, charge transfer from the Li-atoms is remarkable and highly localized at N-atomic sites, where configurations are energetically favored in which both N atoms of the dimers are bound to Li atoms. Conversion of nitrogen sites is different for the two forms of aniline dimers and incomplete up to high intercalation levels, indicating a pronounced role of solid-state effects in the formation of such compounds. 相似文献
74.
75.
D. Braga S. L. Giaffreda M. Curzi Lucia Maini M. Polito Fabrizia Grepioni 《Journal of Thermal Analysis and Calorimetry》2007,90(1):115-123
Supramolecular reactions between crystalline materials can be exploited to prepare both hydrogen bonded co-crystals and coordination
networks. Mechanical mixing of molecular crystals as well as kneading provide an alternative, solvent-free, route to novel
materials hence these methods represent a green route to supramolecular solid-state chemistry. 相似文献
76.
Bromate is a well known by-product produced by the ozonisation of drinking water; the allowed concentration for human consumption has to be regulated to the low microg l(-1) range. A direct injection, ion chromatographic method was developed using a tetraborate eluent with serially connected conductivity and spectrophotometric detection. Bromate was detected after post-column reaction with fuchsin at 520 nm. Sample capacity was investigated by injecting large volumes (up to 6 ml) using a high total hardness and chloride tap water. Linear correlation of bromate response with volumes from 1 ml to 6 ml was demonstrated, the main limitation being the overlapping of the chloride peak with bromate. Up to 1.5 ml sample can be injected without any pre-treatment. With more than 1.5 ml injection volume, a sample pre-treatment with a cartridge in Ag and H form, followed by a 10 min degassing in an ultrasonic bath, was needed. This method was validated by analysing secondary reference materials and real samples from a drinking water treatment plant. The method was linear from the limit of quantification to 20 microg l(-1). Reproducibilities in tap water were 18% (5 microg l(-1), n=12) and 21% (1 microg l(-1), n=4) respectively for 1.5 and 6 ml injection volumes with conductivity detection, and 17% at 0.5 microg l(-1) (n=9) with spectrophotometric detection. Calculated detection limits were 0.5 microg l(-1) (6 ml) ahd 2 microg l(-1) (1.5 ml) for conductivity detection and 0.3 microg l(-1) (1.5 ml) for spectrophotometric detection. 相似文献
77.
78.
Vincenzo Aquilanti Simonetta Cavalli Lev Yu. Rusin Mikhail B. Sevryuk 《Theoretical chemistry accounts》1995,90(4):225-256
Summary Various properties of post-adiabatic representations of multichannel Schrödinger equations are described in the general context of adiabatic and classical path approximations as used in atomic and molecular physics. The van der Waals interactions of fluorine, chlorine, and oxygen atoms with rare gases, hydrogen, methane, and hydrogen halides are considered: it is found that in some of these systems, the first-order post-adiabatic scheme exhibits a smaller coupling than the adiabatic representation, thus providing an appropriate choice of the basis functions for a decoupling approximation. 相似文献
79.
Braga D Maini L Mazzotti M Rubini K Masic A Gobetto R Grepioni F 《Chemical communications (Cambridge, England)》2002,(20):2296-2297
Exposure of the solid zwitterion [CoIII(eta 5-C5H4COOH)(eta 5-C5H4COO)] to vapours of formic acid quantitatively produces the co-crystal [CoIII(eta 5-C5H4COOH)(eta 5-C5H4COO)] [HCOOH] without proton transfer from formic acid to the deprotonated -COO- group on the zwitterion; formic acid can be quantitatively removed by mild thermal treatment, regenerating the starting material. 相似文献
80.
Braga D Maini L Giaffreda SL Grepioni F Chierotti MR Gobetto R 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(13):3261-3269
The organometallic zwitterion [Co(III)(eta(5)-C(5)H(4)COOH)(eta(5)-C(5)H(4)COO)] reacts quantitatively as a solid polycrystalline phase with a number of crystalline alkali salts MX (M = K(+), Rb(+), Cs(+), NH(4) (+); X = Cl(-), Br(-), I(-), PF(6)(-), although not in all cation/anion permutations) to afford supramolecular complexes of the formula [Co(III)(eta(5)-C(5)H(4)COOH)(eta(5)-C(5)H(4)COO)](2).M(+)X(-). In some cases, the mechanochemical complexation requires kneading of the two solids with a catalytic amount of water. The characterization of the solid-state products has been achieved by a combination of X-ray single-crystal and powder-diffraction experiments. The hydrogen-bonding interactions have been investigated by solid-state NMR spectroscopy. The mechanochemical reactions imply a profound solid-state rearrangement accompanied by breaking and forming of O-H...O hydrogen-bonding interactions between the organometallic molecules. All compounds could also be obtained by solution crystallization of the inorganic salts in the presence of the organometallic unit. The solid-state complexation of alkali cations by the organometallic zwitterion has been described as a special kind of solvation process taking place in the solid state. 相似文献