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991.
In this paper, we discuss refinements of the well-known triangle inequality and it is reverse inequality for strongly integrable functions with values in a Banach space X. We also discuss refinement of a generalized triangle inequality of the second kind for Lp functions. For both cases, the attainability of the equality is also investigated.  相似文献   
992.
993.
N‐Nitroso compounds containing benzene, fluorene or fluorenone rings were synthesized. Photolysis of these compounds with 312‐nm UV light provided the NO . species, the presence of which was corroborated by use of an EPR method and of 2‐phenyl‐4,4,5,5‐tetramethylimidazolin‐1‐oxyl 3‐oxide (PTIO) as a trapping agent. During irradiation of N‐methyl‐N‐nitroso‐9‐fluorenone carboxamide ( 14 c ) in the absence of PTIO, it underwent decomposition followed by recombination to give the heterocyclic nitric oxide radical 15 . Incorporation of intercalating moieties endowed the N‐nitroso compounds with DNA‐cleaving ability through single‐strand scission upon UV irradiation in a phosphate buffer (pH 5.0–8.0) under aerobic conditions.  相似文献   
994.
It was found that a pitch-catch signal was more sensitive than normal incidence backwall echo of longitudinal wave to subtle flaw conditions in the composites (damages, fiber orientation, low level porosity, ply waviness, and cracks). Both the strength and stiffness depend on the fiber orientation and porosity volume in the composites. The porosity content of a composite structure is critical to the strength and performance of the structure in general. The depth of the sampling volume where the pitch-catch signal came from was relatively shallow with the head- to-head miniature Rayleigh probes, but the depth can be increased by increasing the separation distance of the transmitting and receiving probes. Also, a method was utilized to determine the porosity content of a composite lay-up by processing micrograph images of the laminate. A free software package was utilized to process micrograph images of the test sample. The results from the image processing method were compared with existing data. Beam profile was characterized in unidirectional CFRP(carbon fiber reinforced plastics) using pitch-catch Rayleigh probes and the one-sided pitch-catch technique was utilized to produce C-scan images with the aid of the automatic scanner.  相似文献   
995.
An overview of the recent development of the superconducting FeSe1?x and related compounds is presented. Methods to synthesize high purity polycrystalline samples, single crystals and thin films with preferred orientation are described. In addition to the synthesis of FeSe and FeSeTe, the effects of various partial chemical substitutions on Fe and Se/Te site are described. It was found that the effects of chemical doping to the Se-site or Fe-site are rather different. Ionic size of the dopant is found to play a critical role on the occurrence of superconductivity. We also review the physical properties, including transport, magnetic, and thermal properties. There exist interesting transport anomalies in the resistivity at low temperature, and it was found that a structural distortion at low temperature is critical to the occurrence of superconductivity in these materials. However, the exact origin of these observed anomalies is not clear, and the exact pairing symmetry in FeSe-based superconductors is also still in question.  相似文献   
996.
The magnetic behaviors of granular (Fe65Co35)x(Al2O3)1−x films have been examined. The results show that the coercivity at 5 K first increases sharply from 80 Oe for x = 0.1 to 700 Oe for x = 0.3 and then drops with increasing x. This behavior differs from the system of Fe-SiO2. Considering the interfacial area, we can theoretically explain the difference between these systems. It is concluded that the peak value of coercivity becomes smaller and occurs at a lower value of x for a more rapidly increasing granular size with volume fraction.  相似文献   
997.
Glassy isotactic propylene (PP) films of thickness up to 0.3 mm were obtained by an ultraquenching technique. The structure and properties of the as-quenched and subsequently crystallized samples were characterized by various techniques. Electron microscopy indicates the glass has no structure larger than 25 Å. X-ray diffraction shows PP crystallizes from the glass into a smectic structure at ca. ?20°C and then transforms to monoclinic microcrystals at ca. 40°C; a nodular structure (80 to 100 Å in diameter) was observed on the surface. The transformation temperature increases with the film thickness. Annealing above the α-relaxation temperature results in an increase in the nodule size. A correspondence was found between the diameter of the nodules observed on the surface and long spacings obtained by small-angle X-ray scattering from the bulk. Dynamic mechanical spectra show the presence of two relaxation-like peaks at ca. ?10°C and 10°C for the as-ultraquenched samples. X-ray scattering, differential scanning calorimetry (DSC), and torsion pendulum measurements show PP crystallizes from the glass at a temperature, depending on the rate of heating, that corresponds to the lower relaxation peak temperature.  相似文献   
998.
A picosecond dye laser system producing 4 μJ in a 10 ps pulse is described. This highly stable compact system consists of a nitrogen laser and two cascade pumped dye laser oscillators followed by one amplifier. The Roess-Lin cavity transient technique was applied to compress the input 60 μJ 300 ps N2pulse twice to produce a final output duration of 10 ps. Discrete output wavelengths can be varied by changing the dye laser solution. Spectral and temporal measurements were performed to characterize this laser. A broad spectral emission of ∼ 160 cm-1was observed, consistent with the observed fine temporal structures of 0.09 ps. A model rate equations calculation was also performed with parameters pertinent to the present laser system. This picosecond laser system should find applications in testing and calibration in the picosecond timescale.  相似文献   
999.
Here presented are two limit theorems for a kind of integrals involvingcomplex-valued functions of large numbers. The form of integrals may be regardedas a natural generalization of those integrals occured in the probability limit theoremsof Chung and Erds. Our main result is Theorem 2 whose Proof rests upon some knownresults of [1] and makes an extentive use of Bonnet's second mean value theorem andrelated analytic techniques.  相似文献   
1000.
This paper investigates the electromigration-induced failures of SnAg3.8Cu0.7 flip-chip solder joints. An under-bump metallization (UBM) of a Ti/Cr-Cu/Cu trilayer was deposited on the chip side, and a Cu/Ni(P)/Au pad was deposited on the BT board side. Electromigration damages were observed in the bumps under a current density of 2×104 A/cm2 and 1×104 A/cm2 at 100°C and 150°C. The failures were found to be at the cathode/chip side, and the current crowding effect played an important role in the failures. Copper atoms were found to move in the direction of the electron flow to form intermetallic compounds (IMCs) at the interface of solder and pad metallization as a result of current stressing.  相似文献   
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