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991.
Finitely generated free modular ortholattices. II 总被引:2,自引:0,他引:2
M. Haviar P. Konôpka C. B. Wegener 《International Journal of Theoretical Physics》1997,36(12):2661-2679
992.
Zhu Ning 《高校应用数学学报(英文版)》1998,13(3):241-250
ANOTEONTHEBEHAVIOROFBLOW┐UPSOLUTIONSFORONE┐PHASESTEFANPROBLEMSZHUNINGAbstract.Inthispaper,thefolowingone-phaseStefanproblemis... 相似文献
993.
A. P. Korobko I. V. Levakova S. V. Krasheninnikov A. I. Stash N. A. Kon’kova V. V. Kuz’min N. V. Kozlova T. A. Korobko 《Crystallography Reports》2002,47(1):58-64
The para and ortho isomers of 3,5-dinitro-(4-acetylphenyl)aminobenzoyl (p-bromophenyl)amide (I and II, respectively) are synthesized, and their physicochemical properties and structure are investigated. The para isomer I has a higher melting temperature and is less soluble in organic solvents as compared to the ortho isomer II. The electronic absorption spectra indicate that absorption for molecule I occurs at longer wavelengths than for molecule II. A correlation between the physicochemical properties and the crystal structures of compounds I and II is revealed. Crystals I · 0.5C6H6 are triclinic; the unit cell parameters are a = 11.760(2) Å, b = 13.958(3) Å, c = 15.012(3) Å, α = 108.01(2)°, β = 103.95(1)°, γ = 92.00(2)°, V = 2258.3(8) Å3, space group $P\bar 1$ , and Z = 4. Crystals II are monoclinic; the unit cell parameters are a = 9.302(2) Å, b = 16.380(3) Å, c = 13.480(3) Å, β = 100.09(3)°, V = 2022.1(7) Å3, space group P21/c, and Z = 4. Structures I · 0.5C6H6 and II are characterized by intramolecular and intermolecular hydrogen bonds. 相似文献
994.
We studied the thermal diffusion behavior of the nonionic surfactant solutions C 12E 6/water and C 12E 5/water at different concentrations and temperatures using thermal diffusion forced Rayleigh scattering (TDFRS). Two different types of TDFRS setups have been applied. In the classical TDFRS, we use an argon laser to write the optical grating into the sample by using a small amount of ionic dye to convert the optical grating into a temperature grating. In the other setup, called IR-TDFRS, we use an infrared laser as the writing beam, which utilizes the water absorption band to convert the optical grating into a temperature grating. The measurements by IR-TDFRS show a one-mode signal for all concentrations and temperatures, while the signal in the classical TDFRS consists of two modes for higher temperatures and lower surfactant concentrations (Ning, H.; et al. J. Phys. Chem. B 2006, 110, 10746). We find good agreement between the Soret coefficient determined in the IR-TDFRS and the one derived from the first fast mode in the previous studies. The Soret coefficient of the nonionic solutions is positive and enhanced at the critical point. In general, the Soret coefficient of the micelles tends to increase with temperature. We found that the presence of the second mode observed in the classical TDFRS is related to the addition of the ionic dye, but even with the ionic dye it is not possible to observe a second mode in the IR-TDFRS. The origin of the second mode is discussed in terms of charged micelles and an inhomogenous dye distribution in the temperature gradient. 相似文献
995.
Microfluidics offers an ideal platform to integrate cell-based assays with electric measurements. The technological advances
in microfluidics, microelectronics, electrochemistry, and electrophysiology have greatly inspired the development of microfluidic/electric
devices that work with a low number of cells or single cells. The applications of these microfluidic systems range from the
detecting of cell culture density to the probing of cellular functions at the single-cell level. In this review, we introduce
the recent advances in the electric analysis of cells on a microfluidic platform, specifically related to the quantification
and monitoring of cells in static solution, on-chip patch-clamp measurement, and examination of flowing cells. We also point
out future directions and challenges in this field.
Figure Different microfluidic devices applied to electrical analysis of cells 相似文献
996.
SnO(2) nanotubes were synthesized via a one-pot redox route at room temperature, in which the Kirkendall effect is definitely responsible for the formation of hollow structures. 相似文献
997.
Wu WN Tang N Yan L 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(4):1461-1465
Six complexes of rare earth nitrates (Ln=La, Sm, Eu, Gd, Tb, Dy) with a new amide type ligand, N-(naphthalen-2-yl)-N-phenyl-2-(quinolin-8-yloxy)acetamide (L) have been prepared and characterized by elemental analysis, conductivity measurements, IR and and 1H NMR spectra. Under excitation, Eu(III) and Sm(III) complexes exhibited strong red emissions. And the luminescence intensity of Sm(III) complex is higher than that of Eu(III) complex. Thus the Eu(III) and Sm(III) complexes are the potential light conversion agent. However, the Tb(III) and Dy(III) complexes cannot exhibit characteristic emissions of terbium and dysprosium ions, respectively. The results of phosphorescence spectrum show that the triplet-state energy level of the ligand matches better to the resonance level of Eu(III) than Tb(III) ion. In addition, the luminescence of the Eu(III) complex is also relatively strong in highly diluted tetrahydrofuran solution (2 x 10(-4)mol/L) compared with the powder. This is not only due to the solvate effects but also to the changes of the structure of the Eu(III) complex after being dissolved into the solvents. Furthermore, owing to the co-luminescence effect, the proper La(III) or Gd(III) doped Eu(III) complexes show stronger luminescence than the pure Eu(III) complex. 相似文献
998.
999.
Selective colorimetric and fluorescent detection of HSO4- with sodium(I), magnesium(II) and aluminium(III) xanthone-crown ether complexes 总被引:1,自引:0,他引:1
Shen R Pan X Wang H Yao L Wu J Tang N 《Dalton transactions (Cambridge, England : 2003)》2008,(27):3574-3581
Xanthone-crown ether (1) reacts with NaClO(4), Mg(ClO(4))(2) and Al(ClO(4))(3) forming the one-dimensional chain dinuclear polymer [Na(2).1.(ClO(4))(2)] (2), the mononuclear complex [Mg.1.(H(2)O)(2)](ClO(4))(2) (3) and an interesting sandwich complex [Al.(1)(2).(H(2)O)(6)](ClO(4))(3) (4) with different ratios of metal-to-ligand, respectively. The anion recognition experiment results show that the magnesium complex (3) is a good colorimetric and fluorescent detector for HSO(4)(-) with high sensitivity and selectivity. 相似文献
1000.
Guoyi Bai Hailong Wang Huisen Ning Fei He Guofeng Chen 《Reaction Kinetics and Catalysis Letters》2008,94(2):375-383
A continuous process for the dehydrogenation of cyclohexanol to cyclohexanone on copper-based catalysts was described. The
catalysts were characterized by XRD, XPS and TPR, and Cu0 was found to be the active site for the copper-based catalysts studied. The two carrier catalysts were proved to be more
active than the single carrier ones, and the Cr additive, which mainly existed as the CuCr2O4 phase on the catalyst’s surface, was found to have a significant effect on the activity and stability of the Cu-Cr-Mg-Al
catalyst. 相似文献