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71.
M.D. García-Sanz F.R. Fernández M.G. Fiestras-Janeiro I. García-Jurado J. Puerto 《European Journal of Operational Research》2008
In this paper we study some cooperative models in Markovian queues. We stress the case of several agents agreeing to maintain a common server for their populations in which a priority scheme with preemption has been established. In this situation we propose and characterize an allocation rule for the holding costs that provides core allocations. 相似文献
72.
Production-inventory games were introduced in [Guardiola, L.A., Meca, A., Puerto, J. (2008). Production-Inventory games: A new class of totally balanced combinatorial optimization games. Games Econom. Behav. doi:10.1016/j.geb.2007.02.003] as a new class of totally balanced combinatorial optimization games. From among all core-allocations, the Owen point was proposed as a specifically appealing solution. In this paper we study some relationships of the class of production-inventory games and other classes of new and known games. In addition, we propose three axiomatic characterizations of the Owen point. We use eight axioms for these characterizations, among those, inessentiality and additivity of players’ demands are used for the first time in this paper. 相似文献
73.
In this paper we analyze cooperative games whose characteristic function takes values in a partially ordered linear space.
Thus, the classical solution concepts in cooperative game theory have to be revisited and redefined: the core concept, Shapley–Bondareva
theorem and the Shapley value are extended for this class of games. The classes of standard, vector-valued and stochastic
cooperative games among others are particular cases of this general theory.
The research of the authors is partially supported by Spanish DGICYT grant numbers MTM2004-0909, HA2003-0121, HI2003-0189,
MTM2007-67433-C02-01, P06-FQM-01366. 相似文献
74.
In this paper, we analyze flexible models for capacitated discrete location problems with setup costs. We introduce a major
extension with regards to standard models which consists of distinguishing three different points of view of a location problem
in a logistics system. We develop mathematical programming formulations for these models using discrete ordered objective
functions with some new features. We report on the computational behavior of these formulations tested on a randomly generated
battery of instances. 相似文献
75.
D. Puerto W. Gawelda J. Siegel J. Bonse G. Bachelier J. Solis 《Applied Physics A: Materials Science & Processing》2008,92(4):803-808
We have studied the plasma formation and ablation dynamics in fused silica upon irradiation with a single 120 fs laser pulse
at 800 nm by using fs-resolved pump-probe microscope. It allows recording images of the laser-excited surface at different
time delays after the arrival of the pump pulse. This way, we can extract both the temporal evolution of the surface reflectivity
and transmission, at 400 nm, for different spatial positions in the spots (and thus for different local fluences) from single
series of images. At fluences well above the visible ablation threshold, a fast and large increase of the reflectivity is
induced by the formation of a dense free-electron plasma. The maximum reflectivity value is reached within ≈1.5 ps, while
the normalized transmission decreases within ≈400 fs. The subsequent temporal evolution of both transient reflectivity and
transmission are consistent with the occurrence of surface ablation. In addition, the time-resolved images reveal the existence
of a free-electron plasma distribution surrounding the visible ablation crater and thus formed at local fluences below the
ablation threshold. The lifetime of this sub-ablation plasma is ≈50 ps, and its maximum electron density amounts to 5.5×1022 cm−3. 相似文献
76.
77.
Yilian Fernández-Afonso Gorka Salas Irene Fernández-Barahona Fernando Herranz Cordula Grüttner Jesús Martínez de la Fuente María del Puerto Morales Lucía Gutiérrez 《Particle & Particle Systems Characterization》2020,37(7):2000032
Advanced uses of smartphones are changing lifestyles, and may have a great impact in materials science in the near future. In this work, the use of these devices to develop fast, simple, and cheap methods to characterize magnetic nanoparticle suspensions is tested. A series of dilutions of a wide library of magnetic nanoparticles, composed of iron oxide materials in the range between 3 and 43 nm, with two different shapes and four different coatings is prepared. The colloid color is analyzed using the RGB (red, green, blue) color model. Ratios of these parameters are correlated with the suspension iron concentration and with the nanoparticles average size. A linear relationship between the color (in particular the G/R ratio) and both the colloid iron content and the particles size is found. The link between these parameters allows the development of two new methods to determine either the concentration or the particle size of magnetic nanoparticle suspensions just by acquiring images from suspensions of iron oxide magnetic nanoparticles with a smartphone. 相似文献
78.
In this paper, we address continuous, integer and combinatorial k-sum optimization problems. We analyze different formulations of this problem that allow to solve it through the minimization of a relatively small number of minisum optimization problems. This approach provides a general tool for solving a variety of k-sum optimization problems and at the same time, improves the complexity bounds of many ad-hoc algorithms previously reported in the literature for particular versions of this problem. Moreover, the results developed for k-sum optimization have been extended to the more general case of the convex ordered median problem, improving upon existing solution approaches. 相似文献
79.
Interaction between Anions and Cationic Metal Complexes Containing Tridentate Ligands with exo‐CH Groups: Complex Stability and Hydrogen Bonding
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Dr. Héctor Martínez‐García Dr. Dolores Morales Dr. Julio Pérez Dr. Marcos Puerto Dr. Ignacio del Río 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(19):5821-5834
[Re(CO)3([9]aneS3)][BAr′4] ( 1 ), prepared by reaction of ReBr(CO)5, 1,4,7‐trithiacyclononane ([9]aneS3) and NaBAr′4, forms stable, soluble supramolecular adducts with chloride ( 2 ), bromide, methanosulfonate ( 3 ) and fluoride ( 4 ) anions. These new species were characterized by IR, NMR spectroscopy and, for 2 and 3 , also by X‐ray diffraction. The results of the solid state structure determinations indicate the formation of CH???X hydrogen bonds between the anion (X) and the exo‐C?H groups of the [9]aneS3 ligand, in accord with the relatively large shifts found by 1H NMR spectroscopy in dichloromethane solution for those hydrogens. The stability of the chloride adduct contrasts with the lability of the [9]aneS3 ligand in allyldicarbonyl molybdenum complexes recently studied by us. With fluoride, in dichloromethane solution, a second, minor neutral dimeric species 5 is formed in addition to 4 . In 4 , the deprotonation of a C?H group of the [9]aneS3 ligand, accompanied by C?S bond cleavage and dimerization, afforded 5 , featuring bridging thiolates. Compounds [Mo(η3‐methallyl)(CO)2(TpyN)][BAr′4] ( 6 ) and [Mo(η3‐methallyl)(CO)2(TpyCH)][BAr′4] ( 7 ) were synthesized by the reactions of [MoCl(η3‐methallyl)(CO)2(NCMe)2], NaBAr′4 and tris(2‐pyridyl)amine (TpyN) or tris(2‐pyridyl)methane (TpyCH) respectively, and characterized by IR and 1H and 13C NMR spectroscopy in solution, and by X‐ray diffraction in the solid state. Compound 6 undergoes facile substitution of one of the 2‐pyridyl groups by chloride, bromide, and methanosulfonate anions. Stable supramolecular adducts were formed between 7 and chloride, bromide, iodide, nitrate, and perrhenate anions. The solid state structures of these adducts ( 12 – 16 ) were determined by X‐ray diffraction. Binding constants in dichloromethane were calculated from 1H NMR titration data for all the new supramolecular adducts. The signal of the bridgehead C?H group is the one that undergoes a more pronounced downfield shift when tetrabutylammonium chloride was added to 7 , whereas smaller shifts were found for the 2‐pyridyl C(3)?H groups. In agreement, both types of C?H groups form hydrogen bonds to the anions in the solid state structures. 相似文献
80.