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91.
Direct product rings have received relatively little attention, perhaps because they are sometimes labeled “trivial” [8, p.6].
Nevertheless, the 2-dimensional direct product ring of the reals, when expressed in the “hyperbolic basis”, is analogous in
many ways to the system of complex numbers and also has a physical interpretation. This prompted an exploratory foray into
the world ofn-dimensional direct product rings of the reals to see how much can be extended from the 2-dimensional case (see, e.g. [3,4,5]).
Section 1 provides algebraic notation, up to the point of defining polar coordinates. Section 2 uses analysis to explore differentiability
and conformality. 相似文献
92.
Using the method of mathematical simulation, we calculate the energy efficiency of the generation of 1,4-di[2-(5-phenyloxazolile)]
benzene solutions in dioxane with allowance for the reabsorption of pumping radiation in a system of excited singlet states.
The results of calculation agree with experimental data.
Deceased.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 6, pp. 744–747, November–December, 1997. 相似文献
93.
Jin Su Park Tae In Ryu Myungkwan Song Kyung‐Jin Yoon Myung Jin Lee In Ae Shin Gi‐Dong Lee Jae Wook Lee Yeong‐Soon Gal Sung‐Ho Jin 《Journal of polymer science. Part A, Polymer chemistry》2008,46(18):6175-6184
The following noble series of soluble π‐conjugated statistical copolymers was synthesized by palladium catalyzed Suzuki polymerization: poly[(9,9‐dioctylfluorene)‐alt‐(4,7‐bis(3′,3′‐dihepyl‐3,4‐propylenedioxythienyl)‐2,1,3‐benzothiadiazole)] (PFO‐PTBT) derived from poly(9,9‐dioctylfluorene) (PFO) and poly[(4,7‐bis(3′,3′‐dihepyl‐3,4‐propylenedioxythienyl)‐2,1,3‐benzothiadiazole)] poly(heptyl4‐PTBT). The structure and properties of these polymers were characterized using 1H‐, 13C‐NMR, UV–visible spectroscopy, elemental analysis, GPC, DSC, TGA, photoluminescence (PL), and cyclic voltammetry (CV). The statistical copolymers, PFO‐PTBT (9:1, 8.4:1.6, 6.5:3.5), were soluble in common organic solvents and easily spin coated onto indium‐tin oxide (ITO) coated glass substrates. The weight‐average molecular weight (Mw) and polydispersity of the PFO‐PTBT ranged from (1.0–4.2) × 104 and 1.5–2.3, respectively. Bulk heterojunction photovoltaic cells with an ITO/PEDOT/PFO‐PTBT:PCBM/LiF/Al configuration were fabricated, and the devices using PFOPTBT (6.5:3.5) showed the best performance compared with those using PFO‐PTBT (9:1, 8.4:1.6). A maximum power conversion efficiency (PCE) of 0.50% (Voc = 0.66 V, FF = 0.29) was achieved with PFO‐PTBT (6.5:3.5). © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6175–6184, 2008 相似文献
94.
Analog (π+, π0) charge exchange on 13C in the (3, 3) resonance region is considered within a modified eikonal formalism, which makes use of traditional eikonalization only for pion-nuclear processes, but not for pion-nucleon processes. Corrections to DWIA, based on two-step processes as suggested by Eisenberg and Gal are evaluated. The calculated charge exchange total cross section is found to increase due to these corrections by 15 %, and is still well below the measured one for Tπ > 150 MeV. 相似文献
95.
96.
Heats of immersion in water (integral heats of hydration) of anhydrous zeolites NaA, CdA, ZnA, CoA, NaX, CdX, ZnX, CoX and NiX have been determined calorimetrically at 25°C. Sodium in NaA and NaX has been replaced by divalent cations to the extent of 70–100% . The data are correlated to the size of the cations and to the standard enthalpy changes of the corresponding ion-exchanged equilibria. The latter values are analysed in terms of three processes: hydration of ions in solution, hydration of zeolites, and electrostatic binding energy of cations to the zeolite framework. 相似文献
97.
We use selection rules developed for Auger-electron spectroscopy to study non-radiative transitions of neutral acceptor bound excitons. We show that (total) angular momentum selection rule implies that excitons originating from the J = 0 and the J = 2 two-hole states have different Auger transition probabilities. The results are shown to be in agreement with photoluminescence experiments. 相似文献
98.
Elemental fluroine was found to substitute, in a regio and stereospecific way, tertiary unactivated hydrogens in alkanes - the most unreactive family of organic compounds. 相似文献
99.
237Np Mössbauer effect and magnetic susceptibility measurements of the U1?NpxO2 fluorite solid solution have been performed in the composition range 0.15 ? x ? 0.75. For x = 0.15 and 0.25, the Np ions order magnetically at a lower temperature T0 than the bulk material (TN) (T0 ~ 19 K, TN ~ 27 K for x = 0.15). For x = 0.50, T0 ~ 10 K (TN ~ 12 K from recent neutron diffraction measurements). For x = 0.75, T0 ~ TN ~ 9 K. The Np (induced) ordered moment is ~ 0.5 μB. The 237Np Mössbauer isomer shift shows that the Np ions are in a IV charge state. 相似文献
100.