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991.
In this paper we study the smoothness properties of solutions to the KP-I equation. We show that the equation's dispersive nature leads to a gain in regularity for the solution. In particular, if the initial data ? possesses certain regularity and sufficient decay as x→∞, then the solution u(t) will be smoother than ? for 0<t?T where T is the existence time of the solution. 相似文献
992.
Hiroki Kumamoto Julie Broggi Vincent Roy Steven P. Nolan Graciela Andrei Daniel Garin Luigi A. Agrofoglio 《Tetrahedron》2008,64(16):3517-3526
In our on-going program targeting anti-pox activity, we report here the synthesis of hitherto unknown acyclic nucleoside phosphonates using olefin cross-metathesis (CM) as a key assembly step. Modification at the C-5 position of the uracil moiety was performed under optimized Pd(0)-catalyzed Stille cross-coupling conditions. None of the obtained compounds were active against poxviruses, nor do they exhibit any toxicity. 相似文献
993.
994.
Michael E. Sigman C. Douglas Clark Kimberly Painter Chatham Milton Ekaterina Simatos Jessica L. Frisch Meghan McCormick Julie L. Bitter 《Rapid communications in mass spectrometry : RCM》2009,23(3):349-356
Oligomeric peroxides formed in the synthesis of triacetone triperoxide (TATP) have been analyzed by mass spectrometry utilizing both electrospray ionization (ESI) and chemical ionization (CI) to form sodiated adducts (by ESI) and ammonium adducts (by CI and ESI). Tandem mass spectrometry and deuterium isotopic labeling experiments have been used to elucidate the collision‐induced dissociation (CID) mechanisms for the adducts. The CID mechanisms differ for the sodium and ammonium adducts and vary with the size of the oligoperoxide. The sodium adducts of the oligoperoxides, H[OOC(CH3)2]nOOH, do not cyclize under CID, whereas the ammonium adducts of the smaller oligoperoides (n < 6) do form the cyclic peroxides under CID. Larger oligoperoxide adducts with both sodium and ammonium undergo dissociation through cleavage of the backbone under CID to form acyl‐ and hydroperoxy‐terminated oligomers of the general form CH3C(O)[OOC(CH3)2]xOOH, where x is an integer less than the original oligoperoxide degree of oligomerization. The oligoperoxide distribution is shown to vary batch‐to‐batch in the synthesis of TATP and the post‐blast distribution differs slightly from the distribution in the uninitiated material. The oligoperoxides are shown to be decomposed under gentle heating. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
995.
996.
Xiuli Qu Ronald L. Rardin Julie Ann S. Williams Deanna R. Willis 《European Journal of Operational Research》2007
Advanced access scheduling, introduced in the early 1990s, is reported to significantly improve the performance of outpatient clinics. The successful implementation of advanced access scheduling requires the match of daily healthcare provider capacity with patient demand. In this paper, for the first time a closed-form approach is presented to determine the optimal percentage of open-access appointments to match daily provider capacity to demand. This paper introduces the conditions for the optimal percentage of open-access appointments and the procedure to find the optimal percentage. Furthermore, the sensitivity of the optimal percentage of open-access appointments to provider capacity, no-show rates, and demand distribution is investigated. Our results demonstrate that the optimal percentage of open-access appointments mainly depends on the ratio of the average demand for open-access appointments to provider capacity and the ratio of the show-up rates for prescheduled and open-access appointments. 相似文献
997.
Jean-Mary Simone François Loiseau David Carcache Pavel Bobal Julie Jeanneret-Gris Reinhard Neier 《Monatshefte für Chemie / Chemical Monthly》2007,138(2):131-139
Summary. A malonylation/decarbalkoxylation sequence from 2-substituted furans was investigated in view of developing a scalable synthesis
of hydrophobic nonactic acid analogues. 相似文献
998.
Roummel F. Marcia Julie C. Mitchell J. Ben Rosen 《Computational Optimization and Applications》2005,32(3):285-297
An algorithm for finding an approximate global minimum of a funnel shaped function with many local minima is described. It
is applied to compute the minimum energy docking position of a ligand with respect to a protein molecule. The method is based
on the iterative use of a convex, general quadratic approximation that underestimates a set of local minima, where the error
in the approximation is minimized in the L1 norm. The quadratic approximation is used to generate a reduced domain, which is assumed to contain the global minimum of
the funnel shaped function. Additional local minima are computed in this reduced domain, and an improved approximation is
computed. This process is iterated until a convergence tolerance is satisfied. The algorithm has been applied to find the
global minimum of the energy function generated by the Docking Mesh Evaluator program. Results for three different protein
docking examples are presented. Each of these energy functions has thousands of local minima. Convergence of the algorithm
to an approximate global minimum is shown for all three examples. 相似文献
999.
Julie Diani Pierre Gilormini Carole Frédy Ingrid Rousseau 《International Journal of Solids and Structures》2012,49(5):793-799
The viscoelastic behavior of an amorphous shape memory polymer network and its dependence on time and temperature were measured by dynamic mechanical analysis. The resulting thermo-mechanical behavior was modeled and implemented in a commercial finite element code. The ability of the resulting thermomechanical model to simulate and, eventually, predict the shape storage and shape recovery of the material was evaluated against experimental shape memory thermomechanical torsion data in a large deformation regimen. The simulations showed excellent agreement with experimental shape memory thermomechanical cycle data. This demonstrates the dependence of the shape recovery on time and temperature. The results suggest that accurate predictions of the shape recovery of any amorphous polymer networks under any thermomechanical conditions combination solely depends on considering the material viscoelasticity and its time–temperature dependence. 相似文献
1000.
We demonstrate an inverse light-scattering analysis procedure based on using the T-matrix method as a light-scattering model. We measure light scattered by in vitro cell monolayers using angle-resolved low-coherence interferometry (a/LCI) and compare the data to predictions of the T-matrix theory. The comparison yields measurements of the equal volume diameter and aspect ratio of the spheroid cell nuclei with accuracy comparable to quantitative image analysis of fixed and stained samples. These improvements represent a significant upgrade for the a/LCI technique, expanding both the range of tissue in which it is applicable and potentially increasing its value as a diagnostic tool. 相似文献