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1.
The Constraint Molecular Dynamics approach is illustrated together with calculation on different heavy ion collisions. In particular the charge-mass distribution produced in the collision 124Sn + 64Ni and 112Sn + 58Ni at 35 MeV/nucleon is discussed. By comparing the Y = (N ? Z)/A distributions for fragments produced in central collisions it results that this observable can be sensitive to the dynamic effects induced on the two systems by the different charge/mass ratio. 相似文献
2.
In this paper, assuming a certain set-theoretic hypothesis, a positive answer is given to a question of H. Kraljevi, namely it is shown that there exists a Lebesgue measurable subsetA of the real line such that the set {c R: A + cA contains an interval} is nonmeasurable. Here the setA + cA = {a + ca: a, a A}. Two other results about sets of the formA + cA are presented. 相似文献
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The preparation of CuI + Ag2S and Cu2[HgI4] + Ag2S membranes hydrophobised by PTFE is described. The pressed membranes mounted in a multi-purpose all-solid-state electrode body have been examined as electrochemical sensors for Cu2+ and I– ions. For the electrode with (CuI + Ag2S + PTFE)-membrane experimental slopes of 29 mV(pCu)–1 and 62 mV(pI)–1 were obtained, in good agreement with the theoretical values. For practical measurement in solutions where both Cu2+ and I– can be present, the investigated electrode offers certain advantages in comparison with a commercial Cu-ISE. 相似文献
5.
D. Berger C. Matei F. Papa G. Voicu V. Fruth 《Progress in Solid State Chemistry》2007,35(2-4):183-191
We report the synthesis of La1−xSrxCoO3 nanopowders by solution combustion method using metal nitrates and -alanine (alanine method) or urea (urea method) as fuel. The influence of metal nitrates/organic substance molar ratio and the type of fuel was investigated. The isolated complex precursors were characterized by atomic absorption spectroscopy (AAS), FT-IR spectra and DTA–TG analysis. The La1−xSrxCoO3 (x = 0–0.3) powders were characterized by X-ray diffraction (XRD), scanning electron microscopy–energy-dispersive X-ray analysis (SEM–EDX), as well as by specific surface area measurements. XRD patterns indicate the formation of single-phase LaCoO3 (rhombohedral) when as-synthesized powders were calcined at 873 K, 3 h in the case of the alanine method and at 1073 K, 3 h for urea-based system. Also, strontium doped lanthanum cobaltites obtained by both methods at 1273 K are single phase with rhombohedral perovskite-like structure as XRD data have proved. SEM investigation of pure and doped lanthanum cobaltites reveal that the samples prepared by both methods have fine particles with tendency of agglomerates formation with different shapes, spongy aspect and high porosity. La1−xSrxCoO3 nanopowders obtained by alanine method have larger specific surface area values than those prepared by urea method. 相似文献
6.
In the present study we give the results of the ab initio calculations on the vibronic, spin-orbit, and magnetic hyperfine structure in the X (2)Pi electronic state of the NCO radical. The calculations of the potential surfaces and the electronic mean values of the hyperfine coupling constants are carried out by means of the density functional theory approach (B3LYP functional combined with an atomic orbital basis set suitable for calculations of the hyperfine structure). The vibronic levels, spin-orbit splitting, and the vibronic mean values of the components of the hyperfine tensor in the vibronic species are calculated using a variational method. The results of the calculations are in good agreement with the available experimental data. 相似文献
7.
The preparation of CuI + Ag2S and Cu2[HgI4] + Ag2S membranes hydrophobised by PTFE is described. The pressed membranes mounted in a multi-purpose “all-solid-state” electrode body have been examined as electrochemical sensors for Cu2+ and I? ions. For the electrode with (CuI + Ag2S + PTFE)-membrane experimental slopes of 29 mV(pCu)?1 and 62 mV(pI)?1 were obtained, in good agreement with the theoretical values. For practical measurement in solutions where both Cu2+ and I? can be present, the investigated electrode offers certain advantages in comparison with a commercial Cu-ISE. 相似文献
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The template effects exerted by guests 14 and 15 in the ring closure reaction of 3 have been quantitatively evaluated. The rate largely increases in the presence of the two templates. The results are compared with those relative to the ring closure reaction of 1 yielding cyclobis(paraquat-p-phenylene), 2. The comparison indicates that the formation of tetracationic aromatic cycles templated by aromatic donors benefits from the use of extended pi surfaces both in the acceptor and in the donor components. 相似文献