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41.
Complexes of phosphated cornstarch and waxy cornstarch with casein were prepared and characterised. They were prepared from casein in defatted milk and corn and waxy corn starches phosphated to degree of substitution values (DS) of 0.0637 and 0.0968, respectively. The components were blended in starch to casein ratios of 2:1, 1:1, and 1:2, then precipitated with hydrochloric acid. Aqueous solubility, water binding capacity, IR spectra, and thermal analysis (thermogravimetry, TG, and differential thermogravimetry, DTG) of the precipitates revealed that they were not simple physical mixtures of the components. The components interact with one another electrostatically with involvement of the starch phosphate groups and the peptide bonds of casein as documented by the IR spectra. Because of their insolubility in 7 M aqueous urea solution they might also be considered as complexes in which the components were chemically bound. Enzymatic studies showed that they are biodegradable materials. 相似文献
42.
JPC – Journal of Planar Chromatography – Modern TLC - A new, simple, accurate, and rapid high-performance thin-layer chromatographic method has been developed for the determination of... 相似文献
43.
A modification of a solution concept of the linear programming problem with interval coefficients in the constraints 总被引:1,自引:0,他引:1
Dorota Kuchta 《Central European Journal of Operations Research》2008,16(3):307-316
We propose a modification of a concept of solving a linear programming problem with interval coefficients in the constraints.
The original concept imposes the decision maker a way comparing intervals, our modification—which is an interactive approach,
comprising the original one as its special case—gives him more freedom in the choice of the preference relation. Thanks to
this flexibility he may be able to find a solution which better suits his needs and attitude towards risk. What is more, our
modification corrects a serious drawback of the original method. 相似文献
44.
Banholzer MJ Li S Ketter JB Rozkiewicz DI Schatz GC Mirkin CA 《The journal of physical chemistry. C, Nanomaterials and interfaces》2008,112(40):15729-15734
We have developed a method to smooth the end sections of nanowires and nanograps generated via the On-Wire Lithography process and studied these rods with optical spectroscopies and theoretical modeling (Discrete Dipole Approximation). The first step of the smoothing process is a reductive one aimed at controlling the diffusion and migration of metal ions to the growing nanorod surface by adjusting the applied potential and concentration of the metal ions in the growth solution. A second oxidative smoothing step, based in part on the energetic differences between topologically rough and smooth surfaces, is used to further smooth the nanorod. The RMS roughness can be reduced over five fold to approximately 5 nm. The properties of these smoothed rods were investigated by empirical and theoretical methods, where it was found the smoothed rods have sharper plasmon resonances and decreased SERS intensity. 相似文献
45.
JPC – Journal of Planar Chromatography – Modern TLC - The chromatographic behavior of some antiarrhythmic compounds has been studied on commercially available TLC plates coated with... 相似文献
46.
Tomasz Manszewski Dorota Prukaa Wiesaw Prukaa Maciej Kubicki 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(10):o493-o495
The crystal structures of the two title (E)‐stilbazolium halogenates, C20H17ClNO+·Cl− and C20H17BrNO+·Br−, are isomorphous, with an isostructurality index of 0.985. The azastyryl fragments are almost planar, with dihedral angles between the benzene and pyridine rings of ca 4.5°. The rings of the benzyl groups are, in turn, almost perpendicular to the azastyryl planes, with dihedral angles larger than 80°. The cations and anions are connected by O—H...X− (X = halogen) hydrogen bonds. The halide anions are `sandwiched' between the charged pyridinium rings of neighbouring molecules, and weak C—H...O hydrogen bonds and C—H...X and C—H...π interactions also contribute to the crystal structures. 相似文献
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In reply to “Comment on the possible role of reaction H+H2O→H2+OH in the radiolysis of water at high temperatures” (Bartels, 2009 Comment on the possible role of the reaction H+H2O→H2+OH in the radiolysis of water at high temperatures. Radiat. Phys. Chem. 78, 191–194) we present an alternative thermodynamic estimation of the reaction rate constant k. Based on the non-symmetric standard state convention we have calculated that the Gibbs energy of reaction ΔrG=57.26 kJ mol?1 and the reaction rate constant k=7.23×10?5 M?1 s?1 at ambient temperature. Re-analysis of the thermodynamic estimation (Bartels, 2009 Comment on the possible role of the reaction H+H2O→H2+OH in the radiolysis of water at high temperatures. Radiat. Phys. Chem. 78, 191–194) showed that the upper limit for the rate constant at 573 K is k=1.75×104 M?1 s?1 compared to the value predicted by the diffusion-kinetic modelling (3.18±1.25)×104 M?1 s?1 (Swiatla-Wojcik, D., Buxton, G.V., 2005. On the possible role of the reaction H+H2O→H2+OH in the radiolysis of water at high temperatures. Radiat. Phys. Chem. 74(3–4), 210–219). The presented thermodynamic evaluation of k(573) is based on the assumption that k can be calculated from ΔrG and the rate constant of the reverse reaction which, as discussed, are both uncertain at high temperatures. 相似文献
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