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221.
In this paper we improve on the monotone property of Lemma 1.7.3 in Lakshmikantham et al. (2009) [5] for the case g(t,u)=λu with a nonnegative real number λ. We also investigate the Mittag-Leffler stability of solutions of fractional differential equations by using the fractional comparison principle.  相似文献   
222.
The electrical conductivity of the system Y2O3CeO2 was measured in the temperature range 500–1100°C and Po2 range 10–7?10?1 atm. Possible defect models were suggested on the basis of conductivity data, which were investigated as a function of temperature and of Po2. The observed activation energies were 0.40 eV and 1.79 eV in the low- and high-temperature regions, respectively. The observed conductivity dependences on Po2 were σ ∝ P16O2 in the temperature range 500–750°C and σ ∝ P15.3O2 at temperatures from 750–1100°C. It is suggested that the system Y2O3CeO2 shows a mixed ionic plus hole conduction due to an Oi defect and an electronic hole conduction due to a V'''Y defect in the low- and high-temperature regions, respectively.  相似文献   
223.
Choi HS  Taylor HF  Lee CE 《Optics letters》1997,22(23):1814-1816
A temperature-sensor system based on low-coherence interferometry with a fiber Mach-Zehnder interferometer as a phase modulator was implemented. A measurement range of 20 to 800 degrees C with a resolution of 0.025 degrees C (corresponding to 0.0004 fringe) was achieved with a 1-mm-long fiber Fabry-Perot interferometer as the sensing element.  相似文献   
224.

Purpose

The purpose of the study was to validate the diagnostic performance of high-resolution isovolumetric magnetic resonance arthrography (MRA) for intrinsic ligament and triangular fibrocartilage complex (TFCC) tears of the wrist as compared to conventional MR imaging (MRI).

Materials and methods

Forty-eight patients with traumatic TFCC tears at arthroscopy were enrolled. All patients had underwent proton-density- and T2-weighted MRI before arthrography and three-dimensional T1 high-resolution isovolumetric examination (3D-THRIVE) MRA on a 3-T MR. We assessed the presence of scapholunate interosseous ligament (SLIL)/lunotriquetral interosseous ligament (LTIL) or TFCC tears using the arthroscopy as a gold standard.

Results

Arthroscopy revealed 37 TFCC central tears, 15 TFCC peripheral tears, 20 SLIL tears and 13 LTIL tears. Sensitivities of MRI and MRA were 70.3% and 94.6% for detection of TFCC central tears, 60.0% and 93.3% for detection of TFCC peripheral tears, 65.0% and 85.0% for SLIL tears, and 61.5% and 84.6% for LTIL tears. The specificity of the MRI was 100% for the detection of ligaments and TFCC tears. The specificities of the MRA for detection of TFCC central tears, TFCC peripheral tears, SLIL tears and LTIL tears were 100%, 97%, 96.4% and 100%, respectively.

Conclusion

Isovolumetric 3D-THRIVE wrist MRA provided better results for depiction of intrinsic ligament and TFCC tears than wrist MRI.  相似文献   
225.
ZnO nano-network structures with high porosity were prepared for use in the photoelectrodes of binder-free dye-sensitized solar cells (DSSCs) by DC sputtering and subsequent thermal oxidation. Zn thin films prepared at 100 °C showed nano-network structures with high porosity, while those prepared at 25 °C did not. This was partially attributed to the high mobility of sputter-deposited particles that arrived at the surface of the substrate and partially to a supersaturation mechanism. The prepared nano-network Zn was successfully transformed to ZnO without a morphological change via subsequent annealing in air. The power conversion efficiency of DSSCs based on the ZnO nano-network structures exhibited 10 times higher efficiency than those based on ZnO film prepared at 25 °C because of its large surface area for adsorption of dye molecules. The thickness of the ZnO nano-network structures increased linearly at 10 μm h?1 as a function of sputter time. As the film thickness increased, the power conversion efficiency of DSSCs increased from 1.09% to 1.82%.  相似文献   
226.
In recent years, fluorescent probes for the detection of environmentally and biologically important metal cations have received extensive attention for designing and development of fluorescent chemosensors. Herein, we report the photophysical results of 2-(2-fluorobenzoyl)-N-(2-methoxyphenyl) hydrazinecarbothioamide (4) functionalized as Ni (II) sensor in micromolar concentration level. Through fluorescence titration at 488 nm, we were confirmed that ligand 4 showed the remarkable emission by complexation between 4 and Ni (II) while it appeared no emission in case of the competitive ions (Cr3+, Fe2+, Co2+, Ba2+, Cu2+, Ca2+, Na+, K+, Cu+, Cs+). Furthermore, ligand 4 exhibited no toxicity with precise cell permeability toward normal living cells using L929 cell lines in bio imaging experiment investigated through confocal fluorescence microscope. The non-toxic behavior of ligand 4 (assessed by MTT assay) and its ability to track the Ni2+ in living cells suggest its possibility to use in biological system as nickel sensor.
Figure
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227.
Here, an in situ probe for scanning transmission X‐ray microscopy (STXM) has been developed and applied to the study of the bipolar resistive switching (BRS) mechanism in an Al/graphene oxide (GO)/Al resistive random access memory (RRAM) device. To perform in situ STXM studies at the C K‐ and O K‐edges, both the RRAM junctions and the I0 junction were fabricated on a single Si3N4 membrane to obtain local XANES spectra at these absorption edges with more delicate I0 normalization. Using this probe combined with the synchrotron‐based STXM technique, it was possible to observe unique chemical changes involved in the BRS process of the Al/GO/Al RRAM device. Reversible oxidation and reduction of GO induced by the externally applied bias voltages were observed at the O K‐edge XANES feature located at 538.2 eV, which strongly supported the oxygen ion drift model that was recently proposed from ex situ transmission electron microscope studies.  相似文献   
228.
Choi  Bong Dae  Kim  Bara  Wee  In-Suk 《Queueing Systems》2000,36(4):437-442
We obtain an asymptotic behavior of the loss probability for the GI/M/1/K queue as K for cases of <1, >1 and =1.  相似文献   
229.
We present an interpolating, univariate subdivision scheme which preserves the discrete curvature and tangent direction at each step of subdivision. Since the polygon have a geometric information of some original (in some sense) curve as a discrete curvature, we can expect that the limit curve has the same curvature at each vertex as the control polygon. We estimate the curvature bound of odd vertices and give an error estimate for restoring a curve from sampled vertices on curves.  相似文献   
230.
Exact solution of the Schrödinger equation is derived for underdamped, critically damped, and overdamped harmonic oscillators with a driving force. A unitary operator transforming Hamiltonian into a simple form is introduced. The transformed Hamiltonian, represented in terms of a modified frequency ω, is identical with the Hamiltonian of the standard harmonic oscillator for the underdamped oscillator, with the Hamiltonian of a free particle for the critically damped oscillator, and with the Hamiltonian of a system with a harmonic parabolic potential for the overdamped oscillator. The eigenvalues of underdamped oscillator are discrete while those of the critically damped and the overdamped oscillators are continuous.  相似文献   
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