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101.
Miranda Paulo H. de S. Lourenço Estela M. G. Morais Alexander M. S. de Oliveira Pedro I. C. Silverio Priscilla S. de S. N. Jordão Alessandro K. Barbosa Euzébio G. 《Molecular diversity》2021,25(1):1-12
Molecular Diversity - Tuberculosis, caused by Mycobacterium tuberculosis (M. tuberculosis), is still responsible for a large number of fatal cases, especially in developing countries with alarming... 相似文献
102.
Magnetic characterization of maghemite nanoparticles dispersed in surface-treated polymeric template
J. A. H. Coaquira A. F. R. Rodriguez J. G. Santos L. B. Silveira A. C. Oliveira V. K. Garg F. Q. Soares D. Rabelo P. C. Morais 《Hyperfine Interactions》2007,176(1-3):113-117
Magnetic characterization of maghemite nanoparticles dispersed in a polymeric template and treated under different chemical processes is reported in this work. Particle size estimated from magnetic measurements, D M?≈?10 nm, for the free-surfactant sample, is consistent with values determined from XRD analysis and TEM images. The magnetic collapse of sextets towards a quadrupole doublet as the temperature is increased reveals the thermal relaxation of smaller $\upgamma $ -Fe2O3 nanoparticles. Magnetic measurements show a strong irreversibility between ZFC and FC curves suggesting the occurrence of particle–particle interaction. 相似文献
103.
Matos MA Miranda MS Pereira SM Morais VM Liebman JF 《The journal of physical chemistry. A》2007,111(30):7181-7188
The standard (p degrees = 0.1 MPa) molar enthalpy of formation of 1,2,4,5-benzenetetracarboxylic dianhydride in the gaseous phase, -826.8 +/- 3.1 kJ mol-1, was derived from the standard molar enthalpy of combustion, in oxygen, at T = 298.15 K, measured by static bomb combustion calorimetry and the standard molar enthalpy of sublimation, at T = 298.15 K, measured by Calvet microcalorimetry. In addition, density functional theory calculations have been performed with the B3LYP, MPW1B95, and B3PW91 density functionals and the cc-pVTZ basis set for 1,2,4,5-benzenetetracarboxylic dianhydride and 1,2,4,5-benzenetetracarboxylic diimide. Nucleus-independent chemical shifts calculations show that the aromaticity is restricted to the benzenic ring in both compounds even though they are formally 10 pi polynuclear species. 相似文献
104.
Margarida S. Miranda M. Agostinha R. Matos Victor M. F. Morais Joel F. Liebman 《Structural chemistry》2011,22(6):1221-1224
Aromaticity is of continuing interest to the organic chemical community. We recently presented a model for the aromaticity
of carbocyclic and heterocyclic derivatives of indane and indene, i.e. species defined as benzenes fused to 5-membered rings.
The current note extends this model to related derivatives of tetralin and naphthalene, benzenes fused to 6-membered rings.
Explicit species discussed herein are: benzopyran, both α- and β-tetralone, coumarin and quinoline. 相似文献
105.
Leite JF Assreuy AM Mota MR Bringel PH Lacerda RR Gomes Vde M Cajazeiras JB Nascimento KS Pessôa Hde L Gadelha CA Delatorre P Cavada BS Santi-Gadelha T 《Molecules (Basel, Switzerland)》2012,17(3):3277-3290
Lectins are proteins that have the ability to bind specifically and reversibly to carbohydrates and glycoconjugates, without altering the structure of the glycosyl ligand. They are found in organisms such as viruses, plants and humans, and they have been shown to possess important biological activities. The objective of this study was to purify and characterize lectins in the seeds of Clitoria fairchildiana, as well as to verify their biological activities. The results indicated the presence of a lectin (CFAL) in the glutelin acid protein fraction, which agglutinated native rabbit erythrocytes. CFAL was purified by column chromatography ion-exchange, DEAE-Sephacel, which was obtained from a peak of protein retained in the matrix by applying 0.5 M NaCl using the step-wise method. Electrophoretic analysis of this lectin in SDS-PAGE indicated a two band pattern protein molecular mass of approximately 100 and 116 kDa. CFAL proved to be unspecific to all carbohydrates/glycoconjugates in common use for the sugar inhibition test. This lectin showed no significant cytotoxicity to human red blood cells. It was observed that CFAL has anti-inflammatory activity in the paw edema induced by carrageenan model, in which a 64% diminution in edema was observed. Antinociceptive effects were observed for CFAL in the abdominal writhing test (induced by acetic acid), in which increasing doses of the lectin caused reduction in the number of contortions by up to 72%. It was concluded that the purified and characterized lectin from the seeds of Clitoria fairchildiana has anti-inflammatory and antinociceptive activity, and is not cytotoxic to human erythrocytes. 相似文献
106.
M. A. R. Matos V. M. F. Morais C. C. S. Sousa M. V. Roux R. Notario 《Molecular physics》2013,111(13-14):1789-1796
The standard (p°?=?0.1?MPa) molar energies of combustion in oxygen, at T?=?298.15?K, of 1-naphthalenemethanol and 2-naphthalenemethanol were measured by static bomb calorimetry. The values of the standard molar enthalpies of sublimation, at T?=?298.15?K, were obtained by Calvet microcalorimetry. Combining these results the standard molar enthalpies of formation of the compounds, in the gas phase, at T?=?298.15?K, have been calculated.
Energetics of naphthalene derivatives, IV+: a calorimetric and calculational thermochemical study of the isomeric naphthalenemethanols
Published online:
04 December 2010Table 相似文献
107.
J. Xavier M. Oliveira P. Monteiro J. J. L. Morais M. F. S. F. de Moura 《Experimental Mechanics》2014,54(5):829-840
The direct identification of the cohesive law in pure mode I of Pinus pinaster is addressed in this work. The approach couples the double cantilever beam (DCB) test with digital image correlation (DIC). Wooden beam specimens loaded in the radial-longitudinal (RL) fracture propagation system are used. The strain energy release rate in mode I (G I) is uniquely determined from the load–displacement curve by means of the compliance-based beam method (CBBM). This method relies on the concept of equivalent elastic crack length (a eq) and therefore does not require the monitoring of crack propagation during test. DIC measurements are processed with two different purposes. Firstly, the physical evidence of a eq is discussed with regard to actual estimation of the crack length based on post-processing full-field displacement measurements. Secondly, the crack tip opening displacement in mode I (w I) is determined from the displacements near the initial crack tip. The cohesive law in mode I (σ I???w I) is then identified by numerical differentiation of the G I???w I relationship. The methodology and accuracy on this reconstruction are addressed. Moreover, the proposed procedure is validated by finite element analyses including cohesive zone modelling. It is concluded that the proposed data reduction scheme is adequate for assessing the cohesive law in pure mode I of P. pinaster. 相似文献
108.
Madeira PJ Morais TS Silva TJ Florindo P Garcia MH 《Rapid communications in mass spectrometry : RCM》2012,26(15):1675-1686
109.
P. C. Morais V. K. Garg A. C. Oliveira L. B. Silveira J. G. Santos M. M. A. Rodrigues A. C. Tedesco 《Hyperfine Interactions》2009,191(1-3):87-93
The chemical co-precipitation process was used to synthesize (in situ) spherical iron-oxide nanoparticle in sulfonated styrene-divinylbenzene polymeric template. X-ray diffraction technique supports the magnetite phase formation with a mean particle diameter of about 19 nm. The analysis of Mössbauer spectra is consistent with two magnetic splitting patterns assigned to A- and B-iron sites of magnetite, with no visible magnetic relaxation effect even at 297 K. Considering the different experimental time window between Mössbauer spectroscopy and DC magnetization, the results obtained from both techniques are in very good agreement. Magnetic data suggest hosting magnetite nanoparticles interacting antiferromagnetically. 相似文献
110.
Matheus dos Santos Guzella Luben Cabezas-Gómez José Antônio da Silva Cristiana Brasil Maia Sérgio de Morais Hanriot 《Heat and Mass Transfer》2016,52(2):183-195
This study presents a numerical evaluation of the influence of some void fraction correlations over the thermal–hydraulic behavior of wire-on-tube condensers operating with HFC-134a. The numerical model is based on finite volume method considering the homogeneous equilibrium model. Empirical correlations are applied to provide closure relations. Results show that the choice of void fraction correlation influences the refrigerant charge and pressure drop calculations, while no influences the heat transfer rate. 相似文献