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1.
2.
Sexual attraction in the silkworm moth: structure of the pheromone-binding-protein-bombykol complex 总被引:14,自引:0,他引:14
BACKGROUND: Insects use volatile organic molecules to communicate messages with remarkable sensitivity and specificity. In one of the most studied systems, female silkworm moths (Bombyx mori) attract male mates with the pheromone bombykol, a volatile 16-carbon alcohol. In the male moth's antennae, a pheromone-binding protein conveys bombykol to a membrane-bound receptor on a nerve cell. The structure of the pheromone-binding protein, its binding and recognition of bombykol, and its full role in signal transduction are not known. RESULTS: The three-dimensional structure of the B. mori pheromone-binding protein with bound bombykol has been determined by X-ray diffraction at 1.8 A resolution. CONCLUSIONS: The pheromone binding protein of B. mori has six helices, and bombykol binds in a completely enclosed hydrophobic cavity formed by four antiparallel helices. Bombykol is bound in this cavity through numerous hydrophobic interactions, and sequence alignments suggest critical residues for specific pheromone binding. 相似文献
3.
V. V. Samonin V. Yu. Nikonova E. A. Spiridonova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2007,81(8):1271-1275
The preliminary adsorption of water considerably decreased the sorption capacity of fullerene-containing materials with respect to benzene. The effect grew stronger as the content of fullerenes in the adsorbent increased. The possibility of increasing adsorption capacity by treatment with water was studied. The dependence of the sorption capacity of fullerene materials with respect to benzene on the relative water vapor pressure and the sorption capacity with respect to water at the preadsorption stage was determined. 相似文献
4.
A study of the tautomerism of the N-alkyl-3-methoxycarbonyl-4-piperidinones and their hydrochlorides
B. A. Arbuzov O. A. Erastov A. B. Remizov L. Z. Nikonova 《Chemistry of Heterocyclic Compounds》1969,5(1):62-65
The positions of the equilibria of N-alkyl-3-methoxycarbonyl-4-piperidinones in the liquid state, in water, in alcohols, and in CCl4 have been determined by IR and UV spectroscopy. It has been shown that Meyer's equation is not satisfied for them. This is due to the high steric requirements of the solvating electron pair of the nitrogen atom. On the basis of the fact that on passing from the methyl ester of cyclohexan-1-one-2-carboxylic acid to the N-alkyl-3-methoxycarbonyl-4-piperidones the position of the equilibrium in the liquid state and in CCl4 does not shift in the direction of the enol it is deduced that the spatial requirements of the free electron pair of the nitrogen atom do not appreciably exceed the steric requirements of the hydrogen atom. The IR and UV spectra of the chlorides of the N-alkyl-3-methoxycarbonyl-4-piperidinones in the solid state and in water and in alcohols are given. 相似文献
5.
B. A. Arbuzov O. A. Erastov A. B. Remizov L. Z. Nikonova 《Chemistry of Heterocyclic Compounds》1972,5(6):730-736
The tautomerism of N-butyl-2-methoxycarbonyl-4-methylpyrrolid-3-one (I), N-butyl-4-methoxycarbonylpyrrolid-3-one (II), N-butyl-4-methoxycarbonyl-2-methylpyrrolid-3-one (III), N-butyl-4-methoxycarbonylpyrrolid-3-one hydrochloride (IV), and N-butyl-4-methoxy-carbonyl-2-methylpyrrolid-3-one hydrochloride (V) has been studied by UV and IR spectroscopy. It has been found that the esters I–V are highly ionized in aqueous and ethanolic solutions at concentrations of 10–2–10–3 M. On passing from methyl cyclopentran-1-one-2-carboxylate to the esters II and III the position of the equilibrium in heptane and CCl4 shifts in the direction of the keto form. On passing from the esters II and III to the esters IV and V, the position of the equilibrium shifts in the direction of the enol. Meyer's relationship is not satisfied for the esters II and III, while it is satisfied for the esters IV and V. Hypotheses have been put forward on the causes of the phenomena mentioned. 相似文献
6.
Safoklov B. B. Atovmyan E. G. Nikonova L. A. Tkachev V. V. Aldoshin S. M. 《Russian Chemical Bulletin》2002,51(12):2224-2229
Pyrrole-2-carbaldehyde isonicotinoylhydrazone (1) and its hydrate [1·H2O] (2) were studied by single-crystal X-ray diffraction analysis. The introduction of the pyrrole substituent into N"-substituted isonicotinic hydrazide (INH) causes the intramolecular redistribution of the electron density compared to those in INHs studied earlier, which increases the basicity of the hydrazone nitrogen atom (N") involved in intermolecular hydrogen bonding. This effect has not been observed in the structures of N"-substituted INHs and benzhydrazides studied previously. Intermolecular hydrogen bonds play a decisive role in the formation of the crystal structures of 1 and 2. 相似文献
7.
Atovmyan E. G. Nikonova L. A. Filipenko O. S. Fedotova T. N. Aldoshin S. M. 《Russian Chemical Bulletin》2002,51(1):99-104
N"-Substituted isonicotinic hydrazides of the general formula Py—C(=O)—N(H)-N"=C(H)—R, where R is o- (1), m- (2), or p-nitrophenyl (3), were studied by IR spectroscopy and X-ray diffraction analysis. The position of the nitro group in these compounds has no effect on the type of the crystal structure. The crystal packings are based on stacks consisting of antiparallel planar molecules. The molecules from the adjacent stacks are linked to each other via the N—H...NPy hydrogen bonds. Depending on the position of the nitro group, the N...NPy distance increases in the series 3 > 1 > 2 and the energy of the hydrogen bonds decreases (according to the IR spectroscopic data) from 3.9 to 3.1 kcal mol–1. Analysis of the IR spectra demonstrated that the intensity of absorption in the (C—H) stretching region of the pyridine ring increases substantially as the the N—H...NPy hydrogen bond is strengthened. Some regularities of the changes, which are observed for the (NO2) bands in the spectra of the nitrophenyl-containing conjugated molecules in solutions, persist in the crystalline state. 相似文献
8.
V. V. Aksenova R. M. Nikonova V. L. Lad’yanov V. V. Mukhgalin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2014,88(10):1726-1731
The crystal solvates in C60-CCl4 and C70-CCl4 systems obtained by crystallization from CCl4 solution at room temperature were studied by IR Fourier spectroscopy and X-ray diffraction. The C70 · (CCl4) n crystal solvate was obtained and studied for the first time; its hexagonal crystal lattice has unit cell parameters a = 10.658 ± 0.001 Å and c = 10.811 ± 0.002 Å. The temperature ranges of its destruction were determined. 相似文献
9.
N. A. Dudina E. V. Antina A. Yu. Nikonova M. B. Berezin G. B. Guseva A. I. V’yugin 《Russian Journal of General Chemistry》2013,83(10):1941-1943
The homoleptic complexes of Zn(II) with 3,3′,5,5‘-tetraphenyl-2,2’-dipyrrolylmethene and 3,3′,5,5′-tetraphenyl-ms-aza-2,2′-dipyrrolylmethene [ZnL2] have been prepared, and their spectral and luminescent properties have been studied. The complex with 3,3′,5,5′-tetraphenyl-2,2′-dipyrrolylmethene exhibited an intense fluorescence in the nonpolar medium, efficiently quenched in the polar solvents; thus, it can be used as a fluorescent sensor of the medium polarity. 相似文献
10.
V. V. Aksenova R. M. Nikonova V. I. Lad’yanov N. B. Tamm E. V. Skokan B. E. Pushkarev 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(10):1749-1755
The oxidation of C60 and C70 fullerites and C60/C70 mixture is accompanied by the decomposition of the carbon frameworks of the molecules at annealing temperatures of 250 and 445°C. Fourier-IR and HPLC studies show that the oxidation/decomposition of C70 molecules is more active than that of C60. The stages of fullerite interaction with oxygen while heating in air were determined. 相似文献