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991.
992.
Dr. Lorenzo Arrico Prof. Lorenzo Di Bari Dr. Francesco Zinna 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(9):2920-2934
An increasing number of circularly polarized luminescence (CPL) molecular emitters has been developed in recent years and many of them are intended for applications in which high overall CPL efficiencies are required. In order to have a complete picture of the efficiency of a CPL emitter, dissymmetry factor (glum) is not enough. In the following we propose a new quantity, named CPL brightness (BCPL), which takes into account absorption extinction coefficient and quantum yield along with the glum factor. We calculated BCPL value for more than 180 compounds reported in the literature and we analyse data distribution for the main classes of CPL molecular emitters. This tool can be employed to put into context new CPL active compounds and to direct the choice of molecular systems for specific CPL applications. 相似文献
993.
Elena M. Gmez-Sez Natalia Moratalla-Lpez Cndida Lorenzo Herminia Vergara Gonzalo L. Alonso 《Molecules (Basel, Switzerland)》2021,26(7)
At present, the development of new agri-food products, including flavored meat products presented in ready-to-eat vacuum packs, is encouraged. The addition of ingredients used as flavoring agents creates the need to be able to determine the volatile compounds responsible for their characteristic aroma. The aim of this study is to propose, develop, and validate a new method that uses headspace-stir bar sorptive extraction-gas chromatography/mass spectrometry (HS-SBSE-GC/MS) to determine the saffron aroma in cured ham flavored with this spice. Results showed that safranal was the main volatile compound that could be identified and quantified in cured ham flavored with saffron. This analytical method was adequate in terms of linearity, selectivity, sensitivity, and accuracy. To our knowledge, this is the first time that an HS-SBSE-GC/MS method for determining the saffron aroma of flavored cured ham has been developed and validated, and it is of interest to agri-food industries. 相似文献
994.
Dr. Mauro Satta Dr. Anna Rita Casavola Dr. Antonella Cartoni Dr. Mattea Carmen Castrovilli Dr. Daniele Catone Dr. Jacopo Chiarinelli Prof. Stefano Borocci Dr. Lorenzo Avaldi Dr. Paola Bolognesi 《Chemphyschem》2021,22(23):2387-2391
Nitroimidazoles are a class of chemicals with a remarkable broad spectrum of applications from the production of explosives to the use as radiosensitizers in radiotherapy. The understanding of thedynamics of their fragmentation induced by ionizing sources is of fundamental interest. The goal of this work is to theoretically investigate the kinetic competition between the two most important decomposition channels of 2, 4 and 5-Nitroimidazole cations: the NO and NO2 losses. The calculated rate constants of the two processes are in very good agreement with the experimental Photoelectron-Photoion Coincidence (PEPICO) branching ratio. This study solves the intriguing and theoretically unexplained experimental observation that 2-Nitroimidazole, at variance with the other two regio-isomers is a source for only NO at low energies (<12.76 eV). This is a key point for biomedical application of the nitroimidazoles, because NO is the vasodilator that favors the reoxigenation of hypoxic tumor tissues. 相似文献
995.
996.
997.
Ferreiro López-Riobóo Juana Isabel Crespo González Natalia López Mahía Purificación Muniategui Lorenzo Soledad Prada Rodríguez Dario 《Accreditation and quality assurance》2019,24(1):73-78
Accreditation and Quality Assurance - One of the fundamental stages in planning and developing any interlaboratory comparison is the selection and preparation of the test items to be distributed to... 相似文献
998.
999.
Helicene Monomers and Dimers: Chiral Chromophores Featuring Strong Circularly Polarized Luminescence
Cédric Schaack Lorenzo Arrico Eric Sidler Marcin Górecki Lorenzo Di Bari Prof. Dr. François Diederich 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(34):8003-8007
The synthesis and chiroptical properties of a series of enantiomerically pure, C2-symmetrical carbo[6]helicene dimers are reported. Two helicene cores are connected through a buta-1,3-diyne-1,4-diyl linker or a heteroaromatic bridge and bear arylethynyl substituents at their 15-positions. This ensures the possibility of extended electronic communication throughout the whole molecule. The new chromophores exhibit intense ECD spectra with strong bands in the UV/Vis region well above 400 nm. The anisotropy factor gabs (defined as Δϵ/ϵ) reaches values up to 0.047, which are unusually large for single organic molecules. They also display blue fluorescence, with good quantum yields (Φf∼0.25). The emitted light is circularly polarized to an outstanding extent: in some cases, the luminescence dissymmetry factor glum=2(IL−IR)/(IL+IR) attains values of |0.025|. To the best of our knowledge, such values are among the highest ever reported for non-aggregated organic fluorophores. 相似文献
1000.
Luca Capaldo Lorenzo L. Quadri Davide Ravelli 《Angewandte Chemie (International ed. in English)》2019,58(49):17508-17510
The merging of a homogeneous photocatalytic system with an electrochemical cell, having exchanged electrons as the only common point, has been recently demonstrated. This combination opens unexplored pathways in synthesis and allowed net‐oxidative photocatalytic processes to be realized in the absence of a chemical oxidant, including: 1) the C?H alkylation of heteroarenes and 2) the coupling of azoles with arenes in the presence of an electrogenerated photocatalyst. 相似文献