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191.
192.
Inui N Kakuno H Tretyakov AY Komatsu G Kameoka K 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,59(6):6513-6516
We study the percolation properties of a random diode network (RDN) which contains two kinds of directed bonds on a square lattice. This network is a special case of the random insulation-resistor-diode network. Both Monte Carlo simulations and series expansion for the percolation probability show that an estimated critical exponent, beta=0.1794+/-0.008, is different from known values for a conventional insulation-resistor-diode network. RDN belongs to neither the isotropic percolation universality class nor to the directed percolation universality, which we attribute to a difference of symmetry breakdown around the critical point. 相似文献
193.
Fullerene derivatives having a terthiophene unit connected by a triple bond were newly synthesized and the electroactive polymers were obtained by electrolytic oxidation of the terthiophene moiety. 相似文献
194.
Ryu I Miyazato H Kuriyama H Matsu K Tojino M Fukuyama T Minakata S Komatsu M 《Journal of the American Chemical Society》2003,125(19):5632-5633
Free-radical mediated stannylcarbonylation of azaenynes provides a general [n + 1]-type annulation approach leading to alpha-stannylmethylene lactams. The cyclization is unusual in its breadth, covering 4-exo, 5-exo, 6-exo, 7-exo, and 8-exo modes. 相似文献
195.
T. Nishida M. Katada N. Osawa R. Sato T. Komatsu K. Matusita 《Hyperfine Interactions》1994,94(1):2119-2124
The119Sn-Mössbauer spectra ofxSnO·(70–x)SnF2·30P2O5 glasses (0 x70) measured at 78 K comprised a doublet due to Sn2+ (=3.30–3.36 mm s–1, = 1.70–1.72 mm s–1) and a weak singlet due to Sn4+ located at –0.23 mm s–1 with respect to BaSnO3. The and of Sn2+ were comparable to those of Sn2P2O7. Small Debye temperatures (146 and 155 K) were obtained from the low-temperature measurements. These results indicate that Sn2+ and Sn4+ occupied interstitial sites, being loosely and ionically bonded to distorted PO4–x
F
x
tetrahedra. 相似文献
196.
197.
Nakano S Uotani Y Nakashima S Anno Y Fujii M Sugimoto N 《Journal of the American Chemical Society》2003,125(27):8086-8087
Novel deoxyadenosine derivatives tethering a phenyl or naphthyl group by means of an amido linker have been synthesized, and these derivatives, stacking on the 5' end of a DNA duplex, provide free energy contributions equal to or greater than that of the Watson-Crick A/T base pair. 相似文献
198.
[reaction: see text] A singly bonded C60 dimer having a diethoxyphosphorylmethyl group on each C60 cage was obtained by the reaction of C60(2-) dianion with diethyl iodomethylphosphonate followed by the treatment with iodine. The precise structure of the dimer was determined for the first time by X-ray crystallography, and its homolytic dissociation as well as spectroscopic and electrochemical properties were clarified. 相似文献
199.
Mitsuo Komatsu Shinji Yamamoto Yoshiki Ohshiro Toshio Agawa 《Tetrahedron letters》1981,22(38):3769-3772
The reaction of 1-azabutadienes with enolates of substituted acetates gave 3,4-dihydro-2-pyridones which rearrange or dehydrogenate to other isomeric dihydropyridones or pyridones. Thus 1-azabutadienes were found to be good building blocks for pyridone derivatives. 相似文献
200.
Dehydro[12]- and -[18]annulenes 3 and 4 fused with tetrafluorobenzene were newly synthesized by the copper-mediated oxidative coupling of 1,2-diethynyltetrafluorobenzene. The UV-vis spectra of 3 and 4 showed the maximum absorption to be almost identical to that of the corresponding unsubstituted benzodehydro[12]- and -[18]annulenes 1 and 2, respectively, while the reduction waves in cyclic voltammetry observed at potentials of -1.48 and -1.56 V vs Fc/Fc(+) for 3 and 4 were less negative than those for 1 and 2. In agreement with these results, theoretical calculations (B3LYP/6-31G(d)) indicated that the HOMO-LUMO gap is similar for 1 and 3 and for 2 and 4 but that the LUMO levels of 3 and 4 are apparently lowered by the electronegative fluorine substituents. The X-ray crystallography of single crystals grown from 3 (crystal A), 3.C(6)H(6) (crystal B), and a mixture of 1 and 3 (crystal C) demonstrated that the molecules of 3 are stacked in a slanted manner in crystals A and B, while those of 1 and 3 form sandwichlike 1:2 complexes (3.1.3) that are stacked in a columnar arrangement in crystal C. Despite the suitable packing for topochemical polymerization, crystals A-C were quite stable against photochemical reaction. In contrast, differential scanning calorimetry showed that the thermal polymerization occurred explosively at 120-135 degrees C. 相似文献