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81.
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83.
C. Tomas J.P. Girardeau-Montaut M. Afif M. Romand M. Charbonnier T.M. Duc 《Applied Physics A: Materials Science & Processing》1997,64(5):467-471
3+ :YAG laser with 5th harmonic generator, generating 16 ps duration pulses at 213 nm, with energies up to 0.5 mJ. Experimental results concerning
the action of laser pulses, as well as the effects of residual pressure on the cleanliness of the photocathodes surface are
presented and discussed. Influence of laser pulses and residual pressure on the work function of the metal are also investigated.
Received: 15 April 1996/Accepted: 5 November
1996 相似文献
84.
Tomas de Paulis Nabil El Tayar Pierre-Alain Carrupt Bernard Testa Han van de Waterbeemd 《Helvetica chimica acta》1991,74(2):241-254
A large series of orthopramides (= 2-methoxybenzamides), 6-methoxysalicylamides, and 2,6-dimethoxy-benzamides were examined for their affinity to the dopamine D2 receptor. The binding data were correlated with physicochemical parameters and 13C-NMR chemical shifts using the cross-validated partial least-squares method and multiple linear regression analysis. The results quantitate the influence of electronic factors and lipophilicity to D2 receptor binding. They also show that the N-[(1-ethylpyrroIidin-2-yl)methyl] and N-(1-benzylpiperidin-4-yl) side-chains affect the mode of binding of these compounds. 相似文献
85.
Anirudra Parajuli Daniel H. Kwak Luca Dalponte Dr. Niina Leikoski Tomas Galica Ugochukwu Umeobika Dr. Laurent Trembleau Andrew Bent Prof. Kaarina Sivonen Matti Wahlsten Dr. Hao Wang Dr. Ermanno Rizzi Prof. Gianluca De Bellis Prof. James Naismith Prof. Marcel Jaspars Prof. Xinyu Liu Dr. Wael Houssen Dr. David Peter Fewer 《Angewandte Chemie (International ed. in English)》2017,56(2):433-433
86.
A single piston capillary rheometer was modified by the addition of a second chamber with a restricting valve (developed at
the Polymer Centre, Zlín, Czech Republic), which provides backpressure and increasing the pressure in the melted material
during the flow through the die. The Carreau–Yasuda model was employed to fit the measured viscosity data and determine the
temperature and pressure coefficients for polyolefin based binder and its compounds with carbide powder. Both temperature
and pressure sensitivity coefficients are largely dependent on the structure of a polymer, which should be taken into account
for binder-formation’s development. Increasing the loading level of the powder in the compound diminishes the pressure sensitivity
of their flow properties. 相似文献
87.
The dissociative photoionization of 1,1-C(2)H(2)Cl(2), (E)-1,2-C(2)H(2)Cl(2), and (Z)-1,2-C(2)H(2)Cl(2) has been investigated at high energy and mass resolution using the imaging photoelectron photoion coincidence instrument at the Swiss Light Source. The asymmetric Cl-atom loss ion time-of-flight distributions were fitted to obtain the dissociation rates in the 10(3) s(-1) < k < 10(7) s(-1) range as a function of the ion internal energy. The results, supported by ab initio calculations, show that all three ions dissociate to the same C(2v) symmetry ClC═CH(2)(+) product ion. The 0 K onset energies thus establish the relative heats of formation of the neutral isomers, that is, the isomerization energies. The experimental rate constants, k(E), as well as ab initio calculations indicate an early isomerization transition state and no overall reverse barrier to dissociation. The major high energy channels are the parallel HCl loss and the sequential ClC═CH(2)(+) → HCCH(+) + Cl process, the latter in competition with a ClC═CH(2)(+) → ClCCH(+) + H reaction. A parallel C(2)H(2)Cl(2)(+) → C(2)HCl(2)(+) + H channel also weakly asserts itself. The 0 K onset energy for the sequential Cl loss reaction suggests no barrier to the production of the most stable acetylene ion product; thus the sequential Cl-atom loss is preceded by a ClC═CH(2)(+) → HC(Cl)CH(+) reorganization step with a barrier lower than that of the second Cl-atom loss. The breakdown diagram corresponding to this sequential dissociation reveals the internal energy distribution of the first C(2)H(2)Cl(+) daughter ion, which is determined by the kinetic energy release in the first, Cl loss reaction at high excess energies. At low kinetic energy release, this distribution corresponds to the predicted two translational degrees of freedom, whereas at higher energies, the excess energy partitioning is characteristic of only one translational degree of freedom. New Δ(f)H(o)(298K) of 3.7, 2.5, and 0.2 ± 1.75 kJ mol(-1) are proposed for 1,1-C(2)H(2)Cl(2), (E)-1,2-C(2)H(2)Cl(2), and (Z)-1,2-C(2)H(2)Cl(2), respectively, and the proton affinity of ClCCH is found to be 708.6 ± 2.5 kJ mol(-1). 相似文献
88.
Biotransformation of (1S)-2-carene and (1S)-3-carene by Picea abies suspension culture led to the formation of oxygenated products. (1S)-2-Carene was transformed slowly and the final product was identified as (1S)-2-caren-4-one. On the other hand, the transformation of (1S)-3-carene was rapid and finally led to the formation of (1S)-3-caren-5-one and (1S)-2-caren-4-one as equally abundant major products. The time-course of the reaction indicates that some products abundant at the beginning of the reaction (e.g. (1S, 3S, 4R)-3,4-epoxycarane and (1R)-p-mentha-1(7),2-dien-8-ol) were consumed by a subsequent transformations. Thus, a precise selection of the biotransformation time may be used for a production of specific compounds. 相似文献
89.
90.
Jiri Kos Gilles Degotte Dominika Pindjakova Tomas Strharsky Timotej Jankech Tomas Gonec Pierre Francotte Michel Frederich Josef Jampilek 《Molecules (Basel, Switzerland)》2022,27(22)
Due to the urgent need of innovation in the antimalarial therapeutic arsenal, a series of thirty-seven ring-substituted N-arylcinnamanilides prepared by microwave-assisted synthesis were subjected to primary screening against the chloroquine-sensitive strain of P. falciparum 3D7/MRA-102. The lipophilicity of all compounds was experimentally determined as the logarithm of the capacity factor k, and these data were subsequently used in the discussion of structure-activity relationships. Among the screened compounds, fourteen derivatives exhibited IC50 from 0.58 to 31 µM, whereas (2E)-N-(4-bromo-2-chlorophenyl)-3-phenylprop-2-enamide (24) was the most effective agent (IC50 = 0.58 µM). In addition, (2E)-N-[2,6-dibromo-4-(trifluoromethyl)- phenyl]-3-phenylprop-2-enamide (36), (2E)-N-[4-nitro-3-(trifluoromethyl)phenyl]-3-phenylprop- 2-enamide (18), (2E)-N-(2-bromo-5-fluorophenyl)-3-phenylprop-2-enamide (23), and (2E)-3-phenyl-N-(3,4,5-trichlorophenyl)prop-2-enamide (33) demonstrated efficacy in the IC50 range from 2.0 to 4.3 µM, comparable to the clinically used standard chloroquine. The results of a cell viability screening performed using THP1-Blue™ NF-κB cells showed that none of these highly active compounds displayed any significant cytotoxic effect up to 20 μM, which makes them promising Plasmodium selective substances for further investigations. 相似文献