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71.
We consider a general minimal time problem with a convex constant dynamics and a lower semicontinuous extended real-valued target function defined on a Banach space. If the target function is the indicator function of a closed set, this problem is a minimal time problem for a target set, studied previously in particular by Colombo, Goncharov and Mordukhovich. We investigate several properties of the Fréchet and proximal subdifferentials for the infimum time function. Also explicit expressions of the above mentioned subdifferentials as well as various directional derivatives are obtained. We provide some examples to show the essentiality of assumptions of our theorems. 相似文献
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Dr. Thibault Pariat Dr. Maxime Munch Martyna Durko-Maciag Prof. Dr. Jaroslaw Mysliwiec Dr. Pascal Retailleau Dr. Pauline M. Vérité Prof. Dr. Denis Jacquemin Dr. Julien Massue Dr. Gilles Ulrich 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(10):3483-3495
2-(2’-Hydroxyphenyl)benzazole (HBX) fluorophores are well-known excited-state intramolecular proton transfer (ESIPT) emitters largely studied for their synthetic versatility, photostability, strong solid-state fluorescence and ability to engineer dual emission, thus paving the way to applications as white emitters, ratiometric sensors, and cryptographic dyes. However, they are heavily quenched in solution, due to efficient non-radiative pathways taking place as a consequence of the proton transfer in the excited-state. In this contribution, the nature of the heteroring constitutive of these rigidified HBX dyes was modified and we demonstrate that this simple structural modification triggers major optical changes in terms of emission color, dual emission engineering, and importantly, fluorescent quantum yield. Investigation of the photophysical properties in solution and in the solid state of a series of ethynyl-TIPS extended HBX fluorophores, along with ab initio calculations demonstrate the very promising abilities of these dyes to act as bright dual-state emitters, in both solution (even in protic environments) and solid state. 相似文献
76.
Dr. Keihann Yavari Dr. Wylliam Delaunay Dr. Nicolas De Rycke Thibault Reynaldo Dr. Paul Aillard Dr. Monika Srebro-Hooper Victoria Y. Chang Dr. Gilles Muller Dr. Denis Tondelier Bernard Geffroy Dr. Arnaud Voituriez Dr. Angela Marinetti Prof. Muriel Hissler Dr. Jeanne Crassous 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(20):5303-5310
Herein, the experimental physicochemical and chiroptical properties of a series of phosphahelicenes are reported, focusing on their UV/Vis absorption, luminescence, electronic circular dichroism, optical rotations, and circularly polarized luminescence. Furthermore, detailed analysis of absorption and ECD spectra performed with the help of quantum-chemical calculations allowed us to highlight general features of these helicenic phosphines. Finally, due to well-suited electrochemical properties and thermal stability, the systems were successfully used as emitters in organic light-emitting diodes. 相似文献
77.
Emmanuel Boissard Serge Cohen Thibault Espinasse James Norris 《Random Structures and Algorithms》2015,47(2):267-283
We consider a random walk with the constraint that each coordinate of the walk is at distance one from the following one. In this paper, we show that this random walk is slowed down by a variance factor with respect to the case of the classical simple random walk without constraint. © 2014 Wiley Periodicals, Inc. Random Struct. Alg., 47, 267–283, 2015 相似文献
78.
Baillie RA Tran T Thibault ME Legzdins P 《Journal of the American Chemical Society》2010,132(43):15160-15161
C-H activation of benzene at 26 °C by (η(5)-C(5)Me(5))W(NO)(CH(2)CMe(3))(η(3)-CH(2)CHCHMe) results after 4 h in the production of five new organometallic complexes, only two of which are isomers of the desired (η(5)-C(5)Me(5))W(NO)(C(6)H(5))(η(3)-CH(2)CHCHMe) compound. In contrast, the identical reaction involving the η(5)-C(5)Me(4)H analogue affords only the phenyl complexes during the first 24 h, thereby facilitating their isolation in good yields. This striking difference in reactivity can be attributed to the lesser steric demands of the η(5)-C(5)Me(4)H ligand that result in its complexes reacting at a significantly slower rate. 相似文献
79.
Varin T Gubler H Parker CN Zhang JH Raman P Ertl P Schuffenhauer A 《Journal of chemical information and modeling》2010,50(12):2067-2078
The main goal of high-throughput screening (HTS) is to identify active chemical series rather than just individual active compounds. In light of this goal, a new method (called compound set enrichment) to identify active chemical series from primary screening data is proposed. The method employs the scaffold tree compound classification in conjunction with the Kolmogorov-Smirnov statistic to assess the overall activity of a compound scaffold. The application of this method to seven PubChem data sets (containing between 9389 and 263679 molecules) is presented, and the ability of this method to identify compound classes with only weakly active compounds (potentially latent hits) is demonstrated. The analysis presented here shows how methods based on an activity cutoff can distort activity information, leading to the incorrect activity assignment of compound series. These results suggest that this method might have utility in the rational selection of active classes of compounds (and not just individual active compounds) for followup and validation. 相似文献
80.
Thibault Cantat Dr. Christopher R. Graves Dr. Brian L. Scott Dr. Jaqueline L. Kiplinger Dr. 《Angewandte Chemie (International ed. in English)》2009,48(20):3542-3542
A standing iceberg illustrates how the soft PNP pincer ligand challenges the metallocene dominance (ship) in actinide chemistry, as described by J. L. Kiplinger and co‐workers in their Communication on page 3681 ff. Replacement of C5Me5 by the PNP ligand is a successful strategy for the promotion of new reactivities and to support new actinide structures. The specific electronic and steric properties of the PNP ligand enable access to structures not available for the C5Me5 ligand set and as yet unreported for uranium. (We thank Mr. Anthony Mancinco for the design of the graphic.)