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991.
We propose and demonstrate a novel all-optical memory to store high-speed optical data for long term. The key elements of the memory are Mach–Zehnder Interferometers (MZIs) incorporating semiconductor optical amplifiers (SOAs), acting as AND gate and regenerator in a loop configuration. The simulations show that the memory can be operated up to 80 Gb/s. In addition, the memory was demonstrated at 21.3 Gb/s. 相似文献
992.
Reflective fiber-optic refractometer based on a thin-core fiber tailored Bragg grating reflection 总被引:1,自引:0,他引:1
A novel reflective refractometer based on a thin-core fiber (TCF) sandwiched between a leading single-mode fiber (SMF) and a fiber Bragg grating (FBG) imprinted SMF stub was demonstrated. The reflection from the fiber stub occurs in two well-defined wavelength bands, corresponding to the Bragg core mode and cladding modes. The TCF section functions as a tailorable bridge between the FBG core mode reflection and the surrounding refractive index (SRI). Linear response with enhanced sensitivity of 133.26 dB/refractive index unit for temperature-immune SRI measurement within the biologically desirable sensing range of 1.33-1.41 has been achieved via cost-effective power detection. 相似文献
993.
994.
Fazaeli Y Amini MM Najafi E Mohajerani E Janghouri M Jalilian A Ng SW 《Journal of fluorescence》2012,22(5):1263-1270
A series of 8-hydroxyquinoline complexes of tin, Q(2)SnCl(2) (Q?=?2-methyl-8-hydroxyquinoline, 8-hydroxyquinoline, 5,7-dibromo-8-hydroxyquinoline, 5-chloro-8-hydroxyquinoline, 5,7-dichloro-8-hydroxyquinoline and 5-nitro-8-hydroxyquinoline) were prepared by reacting stannous dichloride with 8-hydroxyquinoline and its derivatives. All complexes were characterized by elemental analysis, mass spectrometry and infrared, UV-vis and (1)H NMR spectroscopes. Furthermore, the molecular structure of a representative complex, dichlorido-bis(5-nitro-quinolin-8-olato-2N,O)tin(IV), was determined by single-crystal X-ray diffraction. The photoluminescence (PL) properties of all prepared compounds and electroluminescence (EL) property of a selected complex (Q?=?5-chloro-8-hydroxyquinoline) were investigated. The results showed that the emission wavelength can be tuned by electron donating or withdrawing group substituent on 8-hydroxyquinoline. Application of prepared complexes in fabrication of an OLED has been demonstrated. 相似文献
995.
In this paper, we propose a stenography scheme based on predictive differencing to embed data in a grey-image. In order to
promote the embedding capacity of pixel-value differencing (PVD), we use differencing between a predictive value and an input
pixel as the predictive differencing to embed the message where a predictive value is calculated by using various predictors.
If the predictive differencing is large, then it means that the input pixel is located in the edge area and, thus, has a larger
embedding capacity than the pixel in a smooth area. The experimental result shows that our proposed scheme is capable of providing
greater embedding capacity and high quality of stego-images then previous works. Furthermore, we have also applied various
predictors to evaluate our proposed scheme. 相似文献
996.
M. Brazil J. H. Rubinstein D. A. Thomas J. F. Weng N. Wormald 《Journal of Optimization Theory and Applications》2012,155(1):336-354
The gradient-constrained Steiner tree problem asks for a shortest total length network interconnecting a given set of points in 3-space, where the length of each edge of the network is determined by embedding it as a curve with absolute gradient no more than a given positive value m, and the network may contain additional nodes known as Steiner points. We study the problem for a fixed topology, and show that, apart from a few easily classified exceptions, if the positions of the Steiner points are such that the tree is not minimum for the given topology, then there exists a length reducing perturbation that moves exactly 1 or 2 Steiner points. In the conclusion, we discuss the application of this work to a heuristic algorithm for solving the global problem (across all topologies). 相似文献
997.
The assembly of soluble, air-stable, supramolecular structures {(Zn-TPyP)[Cp*Ir{S2C2(B10H10)}]4(THF)2}(2), {(Cu-TPyP)[Cp*Ir{S2C2(B10H10)}]4(THF)2}(3) and {(Zn-TPyP)[Cp*Ir{S2C2(B10H10)}]2.6(CHCl3)}n (4), based on metal-containing moieties [Cp*Ir{S2C2(B10H10)}] (1) bridged by nitrogen-based organic spacers, are described. 相似文献
998.
The lower critical solution temperature (LCST) behaviors of random and segmented copolymers of N-isopropylacrylamide (NIPAM) and acrylic acid (AA) prepared in dioxane and water have been investigated by using ultrasensitive microcalorimetry (US-DSC). The introduction of AA increases the LCST of the former but slightly affects that of the latter. When the molar fraction of AA is low (approximately 2 mol %), the LCST of the segmented copolymer shifts to a higher temperature with increasing pH, while the LCST of the corresponding random copolymer slightly changes. Below the boiling point of water, the random copolymer and segmented copolymer with the molar fraction of AA about 15 mol % no longer exhibit an LCST at pH > 5. The addition of calcium ions leads the LCST of both the segmented copolymer and random copolymer to decrease. Our results suggest that the LCST behavior of the copolymers is determined by the clustering of poly(N-isopropylacrylamide) segments. 相似文献
999.
A microfluidic device with an all-solid-state potentiometric biosensor array was developed using microfabrication technology. The sensor array included a pH indicator, and potassium and calcium ion-selective microelectrodes. The pH indicator was an iridium oxide thin film modified platinum microelectrode and the iridium oxide was deposited by an electrochemical method. The potassium and calcium ion-selective microelectrodes were platinum coated with silicon rubber based ion-selective membranes with respectively potassium (valinomycin) and calcium (ETH 1001) ionophores. The detection system was integrated with a micro-pneumatic pump which can continuously drive fluids into the microchannel through sensors at flow rates ranging from 52.4 microl min(-1) to 7.67 microl min(-1). The sensor array microfluidic device showed near-Nernstian responses with slopes of 62.62 mV +/- 2.5 mV pH(-1), 53.76 mV +/- 3 mV -log[K+](-1) and 25.77 mV +/- 2 mV -log[Ca2+](-1) at 25 degrees C +/- 5 degrees C, and a linear response within the pH range of 2-10, with potassium and calcium concentrations between 0.1 M and 10(-6) M. In this study the device provided a convenient way to measure the concentration of hydrogen, potassium and calcium ions, which are important physiological parameters. 相似文献
1000.
Herein, we present a new method for preparing homoligand 3D coordination polymers. First, a layered metal-organic framework Zn3(BDC)3(H2O)2 x 4DMF 1 (BDC is terephthalate, DMF is N,N-dimethylformamide) was fabricated from a H2BDC by liquid-liquid diffusion. Second, the layered product, 1, was used as a precursor to solvothermally react with further H2BDC at 140-180 degrees C, resulting in two products of BDC insertion into the layered structure. These are [Zn3(p-BDC)4] x 2HPIP, 2 (HPIP is partly protonated piperazine), and [Zn3(p-BDC)3(H2BDC)] x (C6H15NO) x H2O x 3DMF, 3 (C6H15NO is triethylamine N-oxide). Single-crystal X-ray diffraction shows that 2 possesses a layer-pillared structure of mu4-BDC, with 1D channels, while 3 has a layer-pillared structure of mu2-BDC, with 2D channels. N2-sorption experiments show 3 has a relatively high BET surface area of 750 m(2)/g. It is proposed that 2 follows the crystal growth mechanism of Ostwald ripening, whereas the crystal structure of 3 might be formed by an insertion mechanism. 相似文献