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71.
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73.
Can two-photon correlation of chaotic light be considered as correlation of intensity fluctuations? 总被引:2,自引:0,他引:2
Two-photon correlation phenomena, including the historical experiment of Hanbury Brown and Twiss, may have to be described quantum mechanically, regardless of whether the source of radiation is classical or quantum. Supporting this point, we present a ghost imaging type of second-order spatial correlation experiment of chaotic light to show that the classical understanding based on the concept of statistical intensity fluctuations does not give a correct interpretation for the observation. From a practical point of view, this experiment demonstrates the possibility of having high contrast lensless two-photon imaging with chaotic light, suggesting imaging applications for radiations for which no effective lens is available. 相似文献
74.
Giuliano?LazzaroniEmail authorView authors OrcID profile Lorenzo?Nardini 《Journal of Nonlinear Science》2018,28(1):269-304
The aim of this paper is to study the quasistatic limit of a one-dimensional model of dynamic debonding. We start from a dynamic problem that strongly couples the wave equation in a time-dependent domain with Griffith’s criterion for the evolution of the domain. Passing to the limit as inertia tends to zero, we find that the limit evolution satisfies a stability condition; however, the activation rule in Griffith’s (quasistatic) criterion does not hold in general, thus the limit evolution is not rate-independent. 相似文献
75.
Gianni Dal Maso Giuliano Lazzaroni 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2010
We present a variational model to study the quasistatic growth of brittle cracks in hyperelastic materials, in the framework of finite elasticity, taking into account the non-interpenetration condition. 相似文献
76.
Marco Alberto?JavaroneEmail author Giuliano?Armano 《The European Physical Journal B - Condensed Matter and Complex Systems》2013,86(11):474
Language is a complex system that evolves over time, due to several phenomena. In recent years, new communication media are affecting interpersonal written communication. In particular, mobile phones and internet-based communication media are leading people to use a small number of characters when writing messages. Hence, acronyms or abbreviations are used in most cases. In particular, a mobile phone message is usually composed by short phrases, the social network Twitter only allows 140 characters per message and in many online forums users have limited space for questions and answers. Although the use of acronyms dates back to ancient times, nowadays this type of linguistic sign is gaining prestige. In this work, we study the introduction of acronyms in social systems. In particular, we define a simple game for the purpose of analyzing how the use of an acronym spreads in a population, considering its ability to create a shared meaning. We performed many numerical simulations according to the proposed model, showing the creation of acronyms to be the result of collective dynamics in a population. 相似文献
77.
Quantum chaotic maps can efficiently generate pseudorandom states carrying almost maximal multipartite entanglement, as characterized by the probability distribution of bipartite entanglement between all possible bipartitions of the system. We show that such multipartite entanglement is robust, in the sense that, when realistic noise is considered, distillable entanglement of bipartitions remains almost maximal up to a noise strength that drops only polynomially with the number of qubits. 相似文献
78.
Giuliano Bandoli Alessandro Dolmella Stefano Gatto Marino Nicolini 《Journal of chemical crystallography》1994,24(5):301-310
The solid-state structures of four 1,2,3,4-tetrahydroacridines [tacrine hydrochloride monohydrate (1), 7-methoxytacrine hydrochloride monohydrate (2), velnacrine hydrogenmaleate (3) and suronacrine hydrogenmaleate (4)] were determined from single-crystal X-ray diffraction analysis. (1): monoclinic,P21/n, a=8.778(1),b=8.521(1),c=17.603(2)Å, =101.34(1)°. (2): monoclinic,C2/c, a=12.326(7),b=18.050(9),c=13.822(8)Å, =113.70(4)°. (3): triclinic,
,a=7.349(2),b=9.417(3),c=12.557(4)Å, =109.62(2), =98.12(2), =101.18(2)°. (4): monoclinic,P21/n, a=8.513(6),b=18.74(1),c=13.401(6)Å, =91.21(5)°. FinalR factors for compounds(1)–(4) are 0.047, 0.057, 0.057, 0.11, respectively. The overall arrangement of the common aminotetrahydroacridine skeleton looks similar in all derivatives. However, whereas enantiomerization of the unsubstituted cyclohexenyl rings occurs in (1) and (2), onlyquasi-axially hydroxyl substituted diastereomers are found for (3) and (4). This is presumably due to the different propensities for hydrogen bonding of axially vs. equatorially disposed hydroxyl groups with the hydrogenmaleate anions. Empirical and semiempirical calculations were performed to examine the conformational behavior of the four compounds, bothin vacuo and in solution. 相似文献
79.
The structures of 3-methoxy-10-methyl-11-phenyldibenzo[b, f]thiepine (I) [C22H18OS, tetragonal,I41/a, witha=33.81(1),c=6.065(5)Å,Z=16] and 3-allyloxy-10-ethyl-11-phenyldibenzo[b,f]oxepine (II) [C25H22O2, mono-clinic,P21/c,a=12.115(7),b=16.316(9),c=10.136(7)Å,=105.05(9)°,Z=4] have been determined by the symbolic addition procedure and refined by least-squares method to anR of 0.090 for 784 diffractometer-measured reflections (I) and to anR of 0.083 for 442 reflections (II). The dihedral angle between the phenyl-ring mean planes is 111.3° in (I) and 121.1° in (II), the middle seven-membered ring has the boat conformation, and the tricyclic moiety has twist and skew values of 6° and 0.42 Å in (I) and 0.3° and 0.79 Å in (II). The overall conformational characteristic for the tricyclic (6, 7, 6)-dibenzo[b,f]heteroepin derivatives have been reviewed to gain a better understanding of what requirements may be important for interaction of drugs of this class at the receptor site. 相似文献
80.
Celebre G Cinacchi G De Luca G Giuliano BM Iemma F Melandri S 《The journal of physical chemistry. B》2008,112(7):2095-2101
The conformational distribution of methyl phenyl sulfoxide (a molecule representative of a very important class of reagents widely used in asymmetric synthesis) has been studied in two different phases of matter (gas phase and solution) by a comprehensive approach including theoretical calculations, microwave spectroscopy, liquid crystal NMR experiments, and atomistic molecular dynamics computer simulations. The aim was to investigate the combined action of intra- and intermolecular interactions in determining the molecule's conformational equilibrium, upon which important physicochemical properties (inter alia, the chemoselectivity) significantly depend. Basically, the results converge in describing the tendency of the molecule to favor stable conformations governed by intramolecular interactions (in particular, the expected optimization between steric repulsion and conjugation of pi systems). However, significant solvent effects (whose "absolute" magnitude is actually difficult to assess, due to a certain "method-dependence" of the results) have been also detected. 相似文献