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101.
In 1981 N. Herbert proposed a gedanken experiment in order to achieve by the "First Laser-Amplified Superluminal Hookup" (FLASH) a faster-than-light (FTL) communication by quantum nonlocality. The present work reports the first experimental realization of that proposal by the optical parametric amplification of a single photon belonging to an entangled EPR pair into an output field involving N=5 x 10{3} photons. A theoretical and experimental analysis explains in general and conclusive terms the precise reasons for the failure of the FLASH program as well as of any similar FTL proposals. 相似文献
102.
Tuccinardi T Nuti E Ortore G Supuran CT Rossello A Martinelli A 《Journal of chemical information and modeling》2007,47(2):515-525
The ability of Gold software to predict the binding disposition of carbonic anhydrase (CA) inhibitors was evaluated using CA II as a case study. The best procedure was subsequently used for docking almost 300 CA II ligands, and the best poses were used as an alignment tool for the development of a 3D quantitative structure-activity relationship (QSAR) study. Evaluation of the resulting 3D-QSAR model allowed us to indicate the ligand properties and residues important for CA II inhibition. Since CAs are an important target involved in many pathologies such as glaucoma, obesity, and tumors, the results obtained could accurately predict the binding affinity of newly designed CA II inhibitors. Furthermore, it is reasonable that this strategy could be profitably used also for the investigation of other CAs. 相似文献
103.
The mono- and bis(sulfooxy) derivatives of ursodeoxy-cholic acid are, contrary to a previous report, easily prepared by a very simple direct sulfation procedure. 相似文献
104.
Lucia Zetta Enrica Alberti Tiziano Motta Maurizio Canetti Fabio Bertini 《Journal of polymer science. Part A, Polymer chemistry》2007,45(20):4635-4646
Butadiene‐isoprene copolymerization with the system V(acac)3‐MAO was examined. Crystalline or amorphous copolymers were obtained depending on isoprene content. Both butadiene and isoprene units exhibit a trans‐1,4 structure and are statistically distributed along the polymer chain. Polymer microstructure, comonomer composition, and distribution along the polymer chain were determined by 13C and 1H NMR analysis. The thermal and X‐ray behaviors of the copolymers were also investigated and compared with results from solid‐state 13C NMR experiments. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4635–4646, 2007 相似文献
105.
Chiara Saggese Alessio Frassoldati Alberto Cuoci Tiziano Faravelli Eliseo Ranzi 《Proceedings of the Combustion Institute》2013,34(1):427-434
The aim of this work is to discuss a lumped approach to the kinetic modeling of the pyrolysis and oxidation of biodiesel fuels, i.e. rapeseed and soybean methyl esters. The lumped model is the natural extension of the kinetic scheme of methyl butanoate and methyl decanoate and takes also a great advantage from the detailed kinetic scheme of biodiesel fuels [Westbrook et al. Combustion and Flame 158 (2011) 742–755]. The combustion of methyl palmitate and methyl stearate is very similar to the one of methyl decanoate, while large unsaturated methyl esters are significantly less reactive at low and intermediate temperatures. The formation of resonantly stabilized allylic radicals from unsaturated methyl esters constitutes a critical element very useful to characterize the reactivity of the different fuels. The extension of the previous kinetic model of hydrocarbon and oxygenated fuel combustion to the methyl esters required the introduction of ~60 lumped species and ~2000 reactions. The dimension of the overall kinetic scheme (~420 species involved in ~13,000 reactions) allows a more flexible and direct application of the model without the need of kinetic reductions. The comparison of model predictions and different sets of experimental data from one side allows to verify the reliability of the proposed model, from the other side calls for further experimental and theoretical work on this subject. 相似文献
106.
Efficient palladium(0)-catalyzed Suzuki-Miyaura cross-couplings are described. The reactions involving potassium aryl- and heteroaryltrifluoroborates with alkenyl bromides can generally be carried out using < or =2 mol % of palladium catalyst and 3 equiv of base in toluene/H2O. When stereodefined alkenyl bromides are employed, the resulting styrene derivatives are accessed stereospecifically. A variety of functional groups are tolerated in both coupling partners. 相似文献
107.
Tiziano Bandiera Franca Marinone Albini Enrico Albini 《Journal of heterocyclic chemistry》1987,24(6):1597-1598
Benzo- and mesitonitrile oxides react with allylamine to yield 5-aminomethyl-2-isoxazolines and open-chain N-substituted amidoximes. The allylamine derivatives were evaluated as potential antifungal and antibacterial agents. The N-allylbenzamidoxime 2a was found to be only moderately active against dermatophytes. 相似文献
108.
After a short summary of the predictions of the Parton Quenching Model (PQM) for the nuclear modification factor and its centrality dependence in Au?Au collisions at RHIC, we concentrate on back-to-back jet-like correlations at high transverse momentum. We illustrate how this probe is biased by the surface effect. 相似文献
109.
S. Moretto M. Lunardon A. Dainese A. Jacholkowski A. Rossi 《Indian Journal of Physics》2011,85(6):917-922
Tracking detectors in high-energy physics experiments require an accurate determination of a large number of alignment parameters
in order to allow a precise reconstruction of tracks and vertices. In addition to the initial optical survey, the use of tracks
in a special software alignment is essential. The methods in use for the alignment of the ALICE Inner Tracking System are
presented, starting from residual-based procedure to fitting systems with many thousands of parameters. The two methods are
reviewed and the preliminary results showed. 相似文献
110.
Antonella Capperucci Alessandro Degl'Innocenti Tiziano Nocentini Giulio Castagnoli Irene Malesci Arianna Cerreti 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5-6):1247-1251
Abstract Bis(trimethylsilyl)sulfide (HMDST) was demostrated to be a very efficient reagent in the delivery of sulfur functionalities, allowing us to synthesize a wide range of thiocarbonyl compounds. The most reactive derivatives were trapped with suitable dienes, leading to the synthesis of different heterocyclic molecules with an high degree of chemo- and regioselectivity. Recently, the mildness of this methodology also allowed us to obtain particularly reactive thiooxocompounds, such as thioformylsilanes, α,β-unsaturated thioaldehydes, thioketones, thioacylsilanes, and thioacylstannanes. 相似文献