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991.
Keiji Kanki Atsushi Nakazato Ryoji Nomura Fumio Sanda Toshio Masuda 《Journal of polymer science. Part A, Polymer chemistry》2004,42(9):2100-2105
A novel, water‐soluble Rh complex, (nbd)Rh[PPh2(m‐NaOSO2C6H4)] [C(Ph)?CPh2] ( 1 ) was synthesized by the reaction of [(nbd)RhCl]2, Ph2P(m‐NaOSO2C6H4) and Ph2C?C(Ph)Li, whose structure was determined by NMR and IR spectroscopies. The Rh catalyst 1 induced the polymerization of phenylacetylene (PA) in water to give two kinds of polymers; one was soluble in organic solvents such as tetrahydrofuran (THF) and CHCl3, and the other was insoluble in common organic solvents. The polymerization of sodium p‐ethynylbenzoate (p‐NaOCO‐PA) homogeneously proceeded with 1 in water at 60 °C to give the polymer in high yield. Poly(p‐NaOCO‐PA) was treated with 1 N HCl and then reacted with (CH3)3SiCHN2 to obtain poly(p‐MeOCO‐PA). The methyl‐esterified polymer was insoluble in THF and CHCl3, which suggests that the formed poly(p‐MeOCO‐PA) has cis–cisoidal structure. The polymer obtained from the polymerization of [p‐CH3(OCH2CH2)2O2CC6H4]C?CH with 1 in water was soluble in methanol, ethanol, and THF, and partly soluble in water. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2100–2105, 2004 相似文献
992.
993.
This review provides a brief introduction to the Langmuir-Blodgett (LB) technique and to the utilization of ultrathin films in the fields of electronics and optics. The electrical and nonlinear optical properties of the Langmuir-Blodgett monolayer and multilayers of organoruthenium complexes, ferrocene derivatives, metal(4,5-dimercapto-1, 3-dithiol-2-dithiolene)2 complexes, metallophthalocyanines, metalloporphyrins, metal(dibenzotetra-aza[14]annulene)s and siloxane polymers are presented. Possible applications of organometallic LB films in sensors, electroluminescence and electrochromic devices, optical switches, solar cells, infrared detectors and harmonic generators are discussed. 相似文献
994.
Experimental endeavor for addressing the origins of life when viewed from the physical perspective presents a new opportunity of developing physics further for its own sake. A case in point is the issue of intensities. The physics of the origins of life may more readily be approachable by way of the dynamics of intensities or intensive quantities such as temperature and force strengths, compared to the standard dynamics of extensive quantities such as molecule numbers, densities, masses and charges. What is unique to the dynamics of intensities is that it is already contextual in addressing the context under which the intensities in focus are generated and maintained. In particular, because of the contextual nature of temperature grounded upon the material context in which the contextual elements move almost randomly with each other, the occurrence of temperature gradients provides an impetus for transforming the material context. The physical origins of life are just associated with the emergence of the robust material context that can serve as a heat engine. One likely candidate for the material context serving as a heat engine that could emerge in the presence of temperature gradients near hot vents in the primitive ocean on the Earth might have been a citric acid cycle running with no help of enzymes of biological origin. Underlying the emergence of a robust heat engine is the pruning principle of the faster temperature drop going with the greater stored latent heat applied to any reacting molecules crossing the temperature gradients. 相似文献
995.
Masashi Harada Masayuki Ohya Takahisa Suzuki Daisuke Kawaguchi Atsushi Takano Yushu Matsushita 《Journal of Polymer Science.Polymer Physics》2005,43(10):1214-1219
Three poly(4‐trimethylsilylstyrene)‐block‐polyisoprenes (TIs), the molecular weights of which were 82,000, 152,000 and 291,000 (TI‐82K, TI‐152K, and TI‐291K), were synthesized by sequential anionic polymerizations. The component polymers were a miscible pair that presented a lower critical solution temperature phase diagram if blended. The TI phase behavior was investigated with transmission electron microscopy. The order–disorder transition could be observed at a temperature between 200 °C (the ordered state) and 150 °C (the disordered state) for the block copolymer TI‐152K. The block copolymer TI‐82K presented the disordered state at 200 °C, whereas TI‐291K was in the ordered state at 150 °C. With the Flory–Huggins interaction parameter between poly(4‐trimethylsilylstyrene) and polyisoprene, which was evaluated by small‐angle neutron scattering for the block copolymers, the TI phase behavior could be reasonably explained by mean‐field theory. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1214–1219, 2005 相似文献
996.
997.
Shouji Minegishi Tetsurou Otsuka Atsushi Kameyama Tadatomi Nishikubo 《Journal of polymer science. Part A, Polymer chemistry》2005,43(14):3105-3115
Phosphorus‐containing vinyl ether monomers and 1‐propenyl ether monomers were prepared by the regioselective addition reaction of glycidyl vinyl ether (GVE) or 1‐propenyl glycidyl ether with diaryl phosphonates with quaternary onium salts as catalysts. The reaction of GVE with bis(4‐chlorophenyl) phenylphosphonate gave bis[1‐(4‐chlorophenoxy methyl)‐2‐(vinyloxy)ethyl]phenylphosphonate in a 68% yield. The structures of the resulting phosphorus‐containing vinyl ether monomers and 1‐propenyl ether monomers were confirmed by IR and 1H NMR spectra and elemental analysis. Photoinitiated cationic polymerizations of the resulting phosphorus‐containing vinyl ether monomers and 1‐propenyl ether monomers were investigated with photoacid generators. The polymerization of vinyl ether groups and 1‐propenyl ether groups of the obtained monomers proceeded very smoothly with a sulfonium‐type cationic photoinitiator, bis[4‐(diphenylsulfonio)phenyl]sulfide‐bis(hexafluorophosphate), upon UV irradiation. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3105–3115, 2005 相似文献
998.
Four wave mixing (FWM) is of considerable interest in generation of a phase conjugate beam with photorefractive crystals. The common methods of FWM are parallel polarization FWM and cross polarization FWM. In this paper, we analyze the phase matching property of the latter. First, we consider the phase matching condition, and derive equations representing the angler relationship of interacting beams. Then, we consider the phase mismatching which is caused by shift of the probe beam angle from the phase matching condition, and calculate the effect of the shift of this angle on the amount of phase mismatching. We also determine and closely examine the coupling constant. 相似文献
999.
Submicron particles larger than about 0.1m in pond and river waters were collected on a carbon film mounted on a specimen grid by centrifugation and then studied morphologically and analyzed for major elements heavier than sodium, with a high-resolution transmission electron microscope equipped with an energy dispersive X-ray analyzer. If available, the data were compared with those of particles artificially prepared under various conditions. Four typical particles—aluminosilicate, quartz, fine-particle aggregates containing silica and iron(III) oxide, and microorganisms—were found in fresh waters. 相似文献
1000.
The de-excitation rate constants of Ne(3P2, 3P0 and 3P1) by N2 and SF6 were measured using a pulse radiolysis method combined with optical absorption spectroscopy. A new absorption law which relates the relative concentration S of absorbing atoms to the measured transmittance T, i.e. in S = Σ11i = 0aiTi, was used for analyzing the data. The presence of a small amount of SF6 in the sample gas mixtures permitted removal of some artifacts due to thermal electrons for determining the rate constants. 相似文献