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151.
152.
153.
Solubilities are reported for carbazole in three binary chloroalkane + dibutyl ether solvent mixtures at 25°C. Results of these measurements are compared with solution models developed for solubility in systems containing specific solute-solvent interactions. A simple model based on a single 1:1 carbazole:dibutyl ether complex described the solubility data, though the calculated equilibrium constant was about one-half of values published previously. A more sophisticated solution model, which assumes both carbazole:dibutyl ether and carbazole:chloroalkane complexes, was needed to thermodynamically describe the systems studied. Equilibrium constants for three presumed carbazole:chloroalkane complexes are calculated from measured carbazole solubilities. 相似文献
154.
Robin L.T ChurchillClaudia Sheedy Kerrm Y.F YauJ.Christopher Hall 《Analytica chimica acta》2002,468(2):185-197
Immunoassays are one of the most convenient methods for environmental monitoring, but have been limited so far by low yield and low affinity antibodies (Abs). With the advent of recombinant Ab (rAb) technology and the expression of these Abs in organisms such as yeast, bacteria, insects and plants, widespread monitoring of our food and environment for organic contaminants using immunoassays has become feasible. A multitude of immunoassays have been developed to detect pesticides in soils, ground and river water, foods and biological samples, such as urine and semen. In this paper, we describe advances in Ab production, the move away from using animals, phage-display technologies and the advent of plant-derived Ab expression systems. Finally, we describe future possibilities in Ab technology for environmental monitoring. 相似文献
155.
156.
Alexander Shivanyuk 《Tetrahedron》2005,61(2):349-352
C2V-symmetrical resorcinarene tetraesters 1 form in CDCl3 dimeric capsules encapsulating one Me4N+ cation. The homodimeric capsules of the tetra(3,4,5-trimethoxybenzoate) 1d and tetrabenzoate 1b or tetrafuroylate 1c disproportionate in solution to give quantitatively the heterodimers. The higher stability of the heterodimer is, most probably, caused by π-π attractions between the π-basic trimethoxyphenyl rings of 1d and relatively more π-accepting phenyl or furyl fragments of 1b or 1c. 相似文献
157.
B. S. Narwade P. G. Gawali Rekha Pande G. M. Kalamse 《Journal of Chemical Sciences》2005,117(6):673-676
Dielectric constant (ε’) and dielectric loss (ε") of n-propyl alcohol (PA), ethylenediamine (EDA) and their binary mixtures,
for different mole fractions of ethylenediamine have been experimentally measured at 11.15 GHz microwave frequency. Values
of density (ρ), viscosity (η) and square refractive index (n
D
2
) of binary mixtures as well as those of pure liquids are reported. Excess square refractive index, viscosity and activation
energy of viscous flow have also been estimated. These parameters have been used to explain the formation of complexes in
the system. 相似文献
158.
K. Babu V. Ganesh Shridhar R. Gadre Nour E. Ghermani 《Theoretical chemistry accounts》2004,111(2-6):255-263
Experimental and theoretical studies of electron densities and the corresponding derived entities such as electrostatic potentials have been the primary means of understanding the chemical nature and electronic properties of crystalline substances. Conventional crystal calculation methods such as the embedded cluster models are capable of performing calculations on small and medium-sized molecules, while periodic ab initio methods can treat crystals with up to 200 atoms per unit cell. A linear scaling method, viz. the molecular tailoring approach, has recently been developed for obtaining ab initio quality one-electron properties. In the present study, the molecular tailoring approach is employed to generate electron density, electrostatic potential and interaction density maps with the ibuprofen crystal as a test case. The interaction density and electrostatic potential maps produced in the present work succinctly bring out the actual crystalline environment around a given reference molecule by including the interactions with atoms in its neighborhood. The results obtained from the molecular tailoring approach may thus be expected to enhance our understanding of the environment in the crystalline material with reasonably small computational effort.Contribution to the Jacopo Tomasi Honorary Issue 相似文献
159.
Jesse L. Kuiper 《Journal of organometallic chemistry》2007,692(8):1653-1660
The reaction between the new hydroxy compound [PPh4][Ru(N)(OH)2Me2] and Pd(OSiMe3)2((−)-sparteine) produces (Me3Si)2O, H2O and a new heterobimetallic compound [PPh4][Ru(N)Me2(μ2-O)2Pd((−)-sparteine)] in good yield. The Ru/Pd bimetallic compound catalyzes the oxidation of aryl and allyl alcohols to the corresponding carbonyl compound in air and the rearrangement of allylic alcohols unsaturated aldehydes. It also oxidizes PPh3 to O-PPh3 under O2. 相似文献
160.
Jin-Woong?Kim Jin-Gyu?Park Jee-Hyun?Ryu Ih-Seop?Chang Kyung-Do?SuhEmail author 《Colloid and polymer science》2005,283(11):1233-1240
This study presents a method to produce monodisperse chloromethyl-functionalized macroporous poly(styrene-co-divinylbenzene) polymer particles by seeded polymerization in aqueous media. We observed that the molecular structure of
polystyrene seed particles, the composition of the secondary monomer mixtures, and the type of solvents were very important
factors that determine the morphology and porosity of the final particles. This study proposes that the molecular chemistry
of polystyrene seed polymers, increasing molecular weight or crosslinking, is another factor that can control the porosity
of the final particles. Also, the selection of a poor solvent was effective in forming the larger surface area. In this study,
it was confirmed that the chloromethyl groups introduced on the surface of porous particles were quantified chemically and
their effective incorporation had a close relationship with the surface area. 相似文献