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71.
Two cyclic diarylheptanoids, garugamblin-3 (1) and acerogenin L (2), isolated from the MeOH extract of the fruits of Alnus japonica Steud., inhibited human low-density lipoprotein (LDL) oxidation in the thiobarbituric acid-reactive substance assay with IC50 values of 2.9 and 1.7 microM, respectively, and they also inhibited cell-mediated LDL oxidation more than five times more strongly than that of a well-known antioxidant, probucol, at a concentration of 10 microM. 1 had no effect on the anti-atherogenesis in low-density lipoprotein receptor- deficient mice.  相似文献   
72.
73.
The first measurement of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at a center-of-mass energy per nucleon pair √ S NN = 2.76 TeV is presented. For an event sample corresponding to the most central 5% of the hadronic cross section, the pseudorapidity density of primary charged particles at midrapidity is 1584 ± 4(stat) ± 76(syst), which corresponds to 8.3 ± 0.4(syst) per participating nucleon pair. This represents an increase of about a factor 1.9 relative to pp collisions at similar collision energies, and about a factor 2.2 to central Au-Au collisions at √ S NN = 2.76 TeV. This measurement provides the first experimental constraint for models of nucleus-nucleus collisions at LHC energies.  相似文献   
74.
We report the first measurement of charged particle elliptic flow in Pb-Pb collisions at sqrt[S(NN)] =2.76 TeV with the ALICE detector at the CERN Large Hadron Collider. The measurement is performed in the central pseudorapidity region (|η|<0.8) and transverse momentum range 0.2

相似文献   

75.
We investigated the effects of in situ plasma-treatment on optical and electrical properties of index-matched indium tin oxide (IMITO) thin film. To render the IMITO-coated surface hydrophilic and study the optical and electrical characteristics, we performed in situ oxygen plasma post-treatment without breaking vacuum. The 94.6% transmittance in the visible wavelength range (400-700 nm) increased on average to 96.4% and the maximum transmittance reached 98% over a broad wavelength range. The surface roughness and sheet resistance improved from 0.9 nm and 200 Ω/sq to 0.0905 nm and 100 Ω/sq, respectively, by in situ plasma post-treatment. We confirmed by contact angle measurement that the hydrophobic IMITO surface was altered to hydrophilic. The improved optical and electrical characteristics of in situ plasma-treated IMITO makes it adequate for high-resolution liquid crystal on silicon displays.  相似文献   
76.
The kinematics of shearing deformation in fiber reinforced materials can lead to fibers that (a) first shorten, (b) then return to their original length, and (c) then elongate. In a hyperelastic constitutive treatment this can cause the shear stress to be a nonmonotone function of the amount of shear if the fibers are sufficiently more stiff than the matrix. Here, we explore how this effects the emergence and development of kink surfaces in the context of a variety of boundary value problems. Kink surfaces are surfaces across which the deformation gradient is discontinuous. For fiber reinforced materials such surfaces generate an abrupt change in the fiber orientation (a kink). We characterize the appearance of kink surfaces in terms of three general mechanisms: fade-in, pair creation, and boundary emission. Each has a counterpart for kink surface disappearance. These mechanisms are highly sensitive both to changes in the original fiber orientation field, including spatial variation in this field, and to changes in the nature of the applied boundary conditions. A variety of examples are presented.  相似文献   
77.
First order autoregressive model indexed by a supercritical Galton–Watson branching process is discussed. Limiting distributions of the least squares estimates are derived both for the stationary and explosive cases. It is shown that a certain random variable inherent in the branching process is acting as a mixing variable in limiting mixture distributions. In particular, with explosive Gaussian case, we obtain a mixture of Cauchy distributions rather than Cauchy.  相似文献   
78.

Purpose

The purpose of the study was to determine significant imaging features to differentiate between infiltrative hepatocellular carcinoma (HCC) and confluent fibrosis (CF) in liver cirrhosis using Gd-EOB-DTPA-enhanced 3-T magnetic resonance imaging.

Material and methods

Nineteen infiltrative HCCs and eight CFs were included. We evaluated the difference in imaging findings and apparent diffusion coefficient (ADC) between the two entities. We compared T2-weighted image (WI) and hepatobiliary phase (HBP) in terms of the clarity of the lesion outer margin.

Results

Seventeen infiltrative HCCs showed lobulated margin, while focal CFs showed either straight (n = 3) or irregular margins (n = 5) (P = .001). All infiltrative HCCs had intact or bulging contours, and all focal CFs showed capsular retraction (P = .001). Fourteen infiltrative HCCs and two focal CFs showed arterial enhancement (P = .035). The ADC of infiltrative HCCs was significantly lower than that of CFs (P = .001). Satellite nodules were noted in 10 infiltrative HCCs. In terms of outer margin clarity, infiltrative HCCs showed a more distinct margin on HBP than on T2-WI (P = .005), while these two sequences were not significantly different in focal CFs (P = 1.000).

Conclusion

HBP improved the imaging characteristics of infiltrative HCC, allowing it to be distinguished from focal CF. Infiltrative HCC showed lower ADC values than focal CF. Lobular configuration, contour bulging, enhancement pattern, associated satellite nodules and portal vein thrombosis were still found to be highly suggestive MR findings for infiltrative HCC.  相似文献   
79.

Ignition and flame propagation for pyrolysing fuel in a cylindrical enclosure has been examined in this study. The pyrolysing fuel of cylindrical shape was located both eccentrically and concentrically inside an outer cylinder that was sustained at high temperature. Due to gravity, buoyancy motion was inevitably incurred in the enclosure, and this was found to affect the flame initiation and propagation behaviour. Radiative heat transfer also played an important role in the thermo-fluid mechanical behaviour because of the high temperature involved in the problem. Numerical studies have been performed for various parameters such as the Grashof number, overheat ratio, gas absorption coefficient and vertical fuel eccentricity. The flame behaviour and initiation were observed to be totally different depending on the Grashof number. Due to absorbed radiant energy, the radiative gas played a significant role in flame evolution. The location of flame onset was also affected by both the vertical eccentricity of the inner pyrolysing fuel and the thermal conditions applied. The heating process and the flow field development were found to govern flame initiation and propagation.  相似文献   
80.
Fluorometric analysis of borohydride (BH4) species by the reduction of arylaldehydes to the corresponding arylmethanols was investigated. 9-Anthracenecarboxaldehyde (9-AA) exhibited pronounced ratiometric fluorescence signaling behavior toward borohydride in alkaline aqueous media. The borohydride-selective signaling of 9-AA was unaffected by the presence of commonly encountered metal ions and anions. 1-Pyrenecarboxaldehyde (1-PA) also showed comparable borohydride signaling behavior. The detection limit was found to be 7.4?μM (0.11?ppm) for 9-AA and 15.7?μM (0.23?ppm) for 1-PA. The utility of the probe with μPAD as a convenient tool for the determination of borohydrides was demonstrated.  相似文献   
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