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111.
Gold nanoparticles were fabricated by reduction of highly concentrated Au(III) ions (200 mM) with casein proteins from milk. The gold nanoparticles were converted to nanoparticle-powders after washing and subsequent vacuum drying without aggregation. The nanoparticle-powders completely re-dispersed in aqueous solution, and stable colloidal gold nanoparticles were obtained. UV-vis extinction spectra and dynamic light scattering (DLS) measurements revealed that large assemblies (size, ca. 3 μm) and subaggregates (size, <0.5 μm) composed of gold nanoparticle-casein protein chain-Au(III) ion were dynamically formed and disintegrated over the course of the growth of the gold nanoparticles. Fourier transform infrared (FT-IR) spectra indicated conformational changes of casein proteins induced by the interaction of casein protein-Au(III) ion and -gold nanoparticle. Finally, rapid, one-pot, and highly concentrated synthetic procedures of gold and silver nanoparticle powders protected by casein (mean diameters below 10 nm) were successfully developed using 3-amino-1-propanol aqueous solutions as reaction media. Dense colloidal gold (40 g L(-1)) and silver (22 g L(-1)) nanoparticle aqueous solutions were obtained by re-dispersing the metal nanoparticle powders. 相似文献
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Silhanek AV Jaime M Harrison N Fanelli VR Batista CD Amitsuka H Nakatsuji S Balicas L Kim KH Fisk Z Sarrao JL Civale L Mydosh JA 《Physical review letters》2006,96(13):136403
We report measurements and analysis of the specific heat and magnetocaloric effect-induced temperature changes at the phase boundary into the single magnetic field-induced phase (phase II) of U(Ru0.96Rh0.04)2Si2, which yield irreversible properties similar to those at the valence transition of Yb(1-x)Y(x)InCu4. To explain these similarities, we propose a bootstrap mechanism by which lattice parameter changes caused by an electric quadrupolar order parameter within phase II become coupled to the 5f-electron hybridization, giving rise to a valence change at the transition. 相似文献
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SAC (symmetry -adapied-cluster) theory has been extended to excted states. Calculations ard reponed for excited States of Be, H2O and CH2 SAC theory reproducer full CI results to high accuracy for suiylet escited states of Be Calculated Rydberg cxcitaiion entrgies tor H2O show good agreement with experiment The singlet—triplet separation in CH2 is estimated to be 11 8 . 相似文献
118.
H. Nakatsuji M. Hada K. Kanda T. Yonezawa 《International journal of quantum chemistry》1983,23(2):387-397
Accurate Hellmann–Feynman force method for the first and second derivatives of energy has been applied to the studies of the chemical reaction systems. We have studied (1) the electronic origins of the structure-reactivity correlations in the reactions CH3 + H → CH4 and CH3 + CH3 → C2H6 and (2) the geometries and force constants in the reaction intermediate and the transition state of the reactions F? + HF → [FHF]? → FH + F? and H? + CH4 → CH4 + H?, respectively. An intuitive simplicity of the underlying concepts of the first and second derivatives of the present approach is shown in the analysis. 相似文献
119.
The excitation and ionization spectra of RuO4 and OsO4 are studied theoretically by the symmetry-adapted cluster (SAC ) and SAC-CI theories. This is the attempt to assign whole of the spectra by ab initio calculations including electron correlations. In the ground state, electron correlations work to reduce the polarity of the M–O bond overestimated in the Hartree–Fock calculation. The Os–O bond is stronger than is the Ru–O bond, which is reflected in the differences of the excitation and ionization spectra of RuO4 and OsO4. The excitation energies of the experimental spectra are well reproduced by the SAC-CI theory, though the calculated intensities of some peaks are very small in comparison with the experiments. The outer-valence ionization spectra calculated by the SAC-CI theory agree well with the experimental photoelectron spectra. Some shake-up peaks that are accompanied with an electron-transfers from oxygen to metal are also calculated. 相似文献
120.
Kodama T Ozawa N Miyake Y Sakaguchi K Nishikawa H Ikemoto I Kikuchi K Achiba Y 《Journal of the American Chemical Society》2002,124(7):1452-1455
The (13)C NMR spectra were measured for three isomers of Tm@C(82), which is one of the divalent metallofullerenes. The molecular symmetries were determined for each isomer: isomer I has C(s) symmetry, isomer II has C(2) symmetry, and isomer III has C(2v) symmetry. Moreover the cage structure of Tm@C(82)(III) was found to be C(82)(9). As a result, it was revealed that Tm@C(82)(III) has a cage identical to that of La@C(82), which is one of the trivalent metallofullerenes. 相似文献