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The pure state space of Quantum Mechanics is investigated as Hermitian Symmetric Kähler manifold. The classical principles of quantum mechanics (Quantum Superposition Principle, Heisenberg Uncertainty Principle, Quantum Probability Principle) and Spectral Theory of observables are discussed in this non-linear geometrical context. 相似文献
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By means of the jet-bundle formalism, the Second Noether Theorem is formulated for a general first-order Lagrangian field theory with infinitesimal local symmetries. These symmetries are implemented by a linear differential operator acting between the sections of a vector bundle and vector fields on the configuration bundle. The problem of the degeneration of the Lagrangian system is examined from a covariant and an instantaneous (i.e. space+time split) viewpoint. It is shown that in the instantaneous approach the presence of infinitesimal local symmetries leads to degeneration of the theory. Vertical local symmetries are shown to imply degeneration also in the covariant formalism. These results can be extended to higher-order Lagrangians as well. 相似文献
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Oscar M. Moradei Cecile M. du Mortier Alicia Fernández Cirelli 《Journal of carbohydrate chemistry》2013,32(6):709-719
ABSTRACT The Horner-Wadsworth-Emmons (HWE) reaction was performed on methyl 3,6-di-O-benzoyl-2-deoxy-α-D-glycero-hex-2-enopyranosid-4-ulose (1) with the potassium enolates of dimethyl [(methoxycarbonyl)methyl]phosphonate (2) or diethyl [(ethoxycarbonyl) methyl]phosphonate (3) under different conditions (metallic cation and solvent) in order to study regio- and stereochemical aspects of the reaction. In the presence of lithium ions, no reaction took place. When sodium enolates were employed, 1,2-addition was the main reaction in chelating solvents, whereas the 1,4-adduct is favoured in the less polar, non chelating toluene. Only 1,2-addition was observed with potassium enolates. Evidence of phosphonate-phosphate rearrangements through five membered cyclic intermediates is described. 相似文献
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Fluoride is an essential element, indispensable for maintenance of dental health. Nevertheless, fluoride concentrations in drinking water above 1.5 mg L−1 may be detrimental to human health. Many methods have been developed for removing excessive fluoride from drinking water, adsorption seems to be an effective, environmentally friendly and economical one. Since the sorption capacity of fluoride below 2 mg L−1 on most conventional adsorbents is not satisfactory, much effort has been devoted to develop new and cost-effective fluoride adsorbents. This review reports the recent developments in the F− removal in water treatment, using chitosan derivatives and composites in order to provide useful information about the different technologies. When possibly the adsorption capacity of chitosan derivatives and composites under different experimental conditions is reported to help to compare the efficacy of the fluoride removal process. A comparison with the adsorption capacity of other low cost adsorbents is also tabled. 相似文献
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The ESR spectrum of a radical produced by photolytically generated t-butoxy radicals and cyclopropene in solution is reported. Arguments are presented for an assignment of the spectrum to the cyclopropenyl radical (CH)3 undergoing fast exchange between equivalent distorted re structures. 相似文献
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We study the fluxes of anti-deuterons that could be produced by annihilations in the galactic halo of Dark Matter particles with multi-TeV mass and a large annihilation cross section, as indicated by the recent PAMELA results. The model of Minimal Dark Matter (MDM) is an example in this category. We find that the fluxes are well within the reach of planned experiments for DM candidates that annihilate mainly into quark pairs, and also extend into the multi-GeV range above the expected astrophysical background. They are instead less promising if the main annihilation channel is into gauge bosons. 相似文献
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The behaviour of orbits of the action of the group of smooth gauge transformations on connections for a principal bundle P(M, G) is discussed with and without compactness assumption on M and G. In the case of compact M and with suitable conditions on G a stratification structure for the space of orbits is established. A natural tame weak Riemannian metric is given on each stratum. 相似文献
8.
Mariano J. L. Castro José Kovensky Alicia Fernández Cirelli 《Journal of carbohydrate chemistry》2013,32(9):1175-1184
ABSTRACT The synthesis of new dimeric carbohydrate-based surfactants was performed connecting two butyl glucopyranosides with a spacer through ester and ether linkages. Critical micellar concentrations were determined to study the influence of anomeric configuration and spacer functionality on surfactant properties. 相似文献
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Xiao-Jun Bi Andrea Addazi Konstantin Belotsky Vitaly Beylin Marco Cirelli Arman Esmaili Nicolao Fornengo Qing-Yu Gan Michael Kachekriess Maxim Khlopov Vladimir Korchagin Alexander Korochkin Vladimir Kuksa Antonino Marciano Andrei Neronov Paolo Panci Roman Pasechnick Alexander Sakharov Filippo Sala Giuseppe Di Sciascio Dimiri Semikoz Pasquale Dario Serpico Nikolay Volchanskiy Peng-Fei Yin 《中国物理C(英文版)》2022,(3):126-138
In order to reveal the nature of dark matter,it is crucial to detect its non-gravitational interactions with the standard model particles.The traditional dark m... 相似文献