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81.
82.
Asymptotic results for weighted means of linear combinations of independent Poisson random variables
Rita Giuliano Claudio Macci 《Stochastics An International Journal of Probability and Stochastic Processes》2020,92(4):497-518
ABSTRACT In this paper we prove the large deviation principle for a class of weighted means of linear combinations of independent Poisson distributed random variables, which converge weakly to a normal distribution. The interest in these linear combinations is motivated by the diffusion approximation in Lansky [On approximations of Stein's neuronal model, J. Theoret. Biol. 107 (1984), pp. 631–647] of the Stein's neuronal model (see Stein [A theoretical analysis of neuronal variability, Biophys. J. 5 (1965), pp. 173–194]). We also prove an analogue result for sequences of multivariate random variables based on the diffusion approximation in Tamborrino, Sacerdote, and Jacobsen [Weak convergence of marked point processes generated by crossings of multivariate jump processes. Applications to neural network modeling, Phys. D 288 (2014), pp. 45–52]. The weighted means studied in this paper generalize the logarithmic means. We also investigate moderate deviations. 相似文献
83.
Nonlinear Dynamics - It is well known that the Lyapunov exponent plays a fundamental role in dynamical systems. In this note, we propose a definition of Lyapunov exponent for Lipschitz maps, which... 相似文献
84.
Giuliano Bandoli Alessandro Dolmella Stefano Gatto 《Journal of chemical crystallography》1995,25(3):143-145
A X-ray crystal structure determination of the title compound was carried out. A comparison of the relevant bond distances and angles in the ring system with other published structures showed that protonation has an influence on the ring geometry. 相似文献
85.
Giuliano F. Bastista Oliveira José Elesbão C. Neto Humberto C. Chaves Fernandes 《International Journal of Infrared and Millimeter Waves》2003,24(7):1159-1169
For the microstrip patch resonator, as a planar antenna of a microstrip, a set of equations that represents the electromagnetic fields in the x and z direction as function of the electric field in the y direction are obtained applying the TTL method. This method is very suitable at microwave and antenna applications, and gives accurate complex resonant frequency, which contributes definitively to obtain higher precision antenna parameters. For each type of array is calculated the array factor, considering the excitation, phase and the relative displacement between the elements as well as the dimensions and number of elements. 相似文献
86.
Giuliano Bandoli Alessandro Dolmella Marino Nicolini Emilio Toja 《Journal of chemical crystallography》1991,21(5):567-574
The molecular structures of the cognition activators (±)1-benzenesulphonyl-2-oxo-5-ethylthiopyrrolidine (1) and (±)1-benzenesulphonyl-2-oxo-5-isopropylthiopyrrolidine (2) were determined by means of X-ray diffraction and semi-empirical quantum mechanical methods. The conformational properties of the compounds, in the solid state andin vacuo (free molecule), were compared with those of the corresponding oxygenated derivatives bearing, in position 5, ethoxy and isopropyloxy substituents, respectively. The molecular arrangements of (1) and (2) in the solid state are similar, with the exception of the side chain on C(5), and they are retained alsoin vacuo. Both present an envelope conformation of the five-membered ring, and the relative positions of the five- and six-membered rings look similar and parallel those of their oxygenated parents. Fromin vacuo calculations another low-energy arrangement seems to be possible, and a detailed examination of the side-chain freedom in (1) and (2) gives more insight in the conformational properties of the compounds. 相似文献
87.
The interaction energy between an incoming group X– and the substrate CRH2Y at the geometry of the transition state (TS) for bimolecular nucleophilic substitution reactions (with X, Y, and R equal to H and F) has been subjected to decomposition according to the Morokuma scheme. The influence of the basis set and of the geometry chosen for the TS is examined. The results bring out regular trends in the different terms of the decomposition along the whole set of reactions, but they are not sufficient to give a rationale of the energetic factors involved in these reactions. 相似文献
88.
Carlo Brunelli Arnaldo Fravolini Giuliano Grandolini M. Cristina Tiralti 《Journal of heterocyclic chemistry》1980,17(1):121-124
Some thiadiazasteroid analogues have been synthesized by the reaction of 3-hydroxymethyl-enebenzo[h]thiochroman-4-one with hydrazine and substituted hydrazines, semicarbazide and thiosemicarbazide. Pmr data supporting the structural assignments have been discussed. 相似文献
89.
Davide Collini Serena Fedi Cristina Femoni Francesco Kaswalder Maria Carmela Iapalucci Giuliano Longoni Piero Zanello 《Journal of Cluster Science》2005,16(3):455-476
The reaction of the [Ni6(CO)12]2− dianion with [Rh(COD)Cl]2 (COD = cyclooctadiene) in acetone affords a mixture of bimetallic Ni–Rh clusters, mainly consisting of the new [Ni7Rh3(CO)18]3− and [Ni8Rh(CO)18]3− trianions. A study of the reactivity of [Ni7Rh3(CO)18]3− led to isolation of the new [Ni3Rh3(CO)13]3− and [NiRh8(CO)19]2− anions. All these new bimetallic Ni–Rh carbonyl clusters have been isolated in the solid state as tetrasubstituted ammonium
salts and have been characterised by elemental analysis, X-ray diffraction studies, ESI-MS and electrochemistry. The unit
cell of the [NEt4]3[Ni7Rh3(CO)18] salt contains two orientationally-disordered ν2-tetrahedral [Ni7Rh3(CO)18]3− trianions with occupancy factors of 0.75 and 0.25. Besides, their inner Ni3Rh3 octahedral moieties show two cis sites purely occupied by Rh atoms, two trans sites purely occupied by Ni atoms and the remaining two cis sites are disordered Ni and Rh sites with respective occupancy fraction of 0.5. At difference from the parent [Ni7Rh3(CO)18]3−, the octahedral [Ni3Rh3(CO)13]3− displays an ordered distribution of Ni and Rh atoms in two staggered triangles. The [NiRh8(CO)19]2− dianion adopts an isomeric metal frame with respect to that of the [PtRh8(CO)19]2− congener. As a fallout of this work, new high-yield synthesis of the known [Ni6Rh3(CO)17]3− and [Ni6Rh5(CO)21]3−, as well as other currently-investigated bimetallic Ni–Rh clusters have been obtained. 相似文献
90.
Oscillator orbitals as expansion functions for the correlation holes have been checked by using them in two simple two electron systems, H2 and Li+.A contraction of the oscillators has been introduced and proved useful to ameliorate energy and convergence rate.
Zusammenfassung Oszillatororbitale als Entwicklungsfunktion zur Darstellung des Korrelationsloches werden durch Anwendung bei zwei einfachen Zweielektronensystemen H2 und Li+ geprüft. Eine Kontraktion der Oszillatoren wird eingeführt, welche die Energie und die Konvergenzgeschwindigkeit verbessert.
Résumé Essai d'orbitales oscillantes comme fonctions de base pour les trous de corrélation dans deux systèmes biélectroniques simples: H2 et Li+.L'introduction d'une contraction des ces orbitales s'est avérée utile pour améliorer l'énergie et la vitesse de convergence.相似文献