277 research outputs found

    АДСОРБЦИОННАЯ ОЧИСТКА ТРАНСФОРМАТОРНОГО МАСЛА СИЛИКАГЕЛЕМ В СОЧЕТАНИИ КЕРАМИЧЕСКИХ МЕМБРАН

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    The results of regeneration of exhaust butter are resulted In the article, power transformer from the protracted exploitation. The methods of the adsorption cleaning of transformer butter are considered. Cleaning of transformer butter is experimentally produced from the different types of admixtures with the use of the developed ceramic membranes. The cleared butter rotined high dielectric properties, and fully conformed to the requirements of normative documents.В статье приведены результаты регенерации отработанного масла, силового трансформатора с длительной эксплуатации. Рассмотрены способы адсорбционной очистки трансформаторного масла. Экспериментально произведена очистка трансформаторного масла от различных видов примесей с применением разработанных керамических мембран. Очищенное масло показало высокие диэлектрические свойства, и вполне соответствовало требованиям нормативных документов

    Hyperfine interaction and magnetoresistance in organic semiconductors

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    We explore the possibility that hyperfine interaction causes the recently discovered organic magnetoresistance (OMAR) effect. Our study employs both experiment and theoretical modelling. An excitonic pair mechanism model based on hyperfine interaction, previously suggested by others to explain magnetic field effects in organics, is examined. Whereas this model can explain a few key aspects of the experimental data, we, however, uncover several fundamental contradictions as well. By varying the injection efficiency for minority carriers in the devices, we show experimentally that OMAR is only weakly dependent on the ratio between excitons formed and carriers injected, likely excluding any excitonic effect as the origin of OMAR.Comment: 10 pages, 7 figures, 1 tabl

    Magnetic properties of the spin-1 chain compound NiCl3_3C6_6H5_5CH2_2CH2_2NH3_3

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    We report experimental results of the static magnetization, ESR and NMR spectroscopic measurements of the Ni-hybrid compound NiCl3_3C6_6H5_5CH2_2CH2_2NH3_3. In this material NiCl3_3 octahedra are structurally arranged in chains along the crystallographic aa-axis. According to the static susceptibility and ESR data Ni2+^{2+} spins S=1S = 1 are isotropic and are coupled antiferromagnetically (AFM) along the chain with the exchange constant J=25.5J = 25.5 K. These are important prerequisites for the realization of the so-called Haldane spin-1 chain with the spin-singlet ground state and a quantum spin gap. However, experimental results evidence AFM order at TN10T_{\rm N} \approx 10 K presumably due to small interchain couplings. Interestingly, frequency-, magnetic field-, and temperature-dependent ESR measurements, as well as the NMR data, reveal signatures which could presumably indicate an inhomogeneous ground state of co-existent mesoscopically spatially separated AFM ordered and spin-singlet state regions similar to the situation observed before in some spin-diluted Haldane magnets

    Upper bounds on the error probabilities and asymptotic error exponents in quantum multiple state discrimination

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    We consider the multiple hypothesis testing problem for symmetric quantum state discrimination between r given states \sigma_1,...,\sigma_r. By splitting up the overall test into multiple binary tests in various ways we obtain a number of upper bounds on the optimal error probability in terms of the binary error probabilities. These upper bounds allow us to deduce various bounds on the asymptotic error rate, for which it has been hypothesised that it is given by the multi-hypothesis quantum Chernoff bound (or Chernoff divergence) C(\sigma_1,...,\sigma_r), as recently introduced by Nussbaum and Szko{\l}a in analogy with Salikhov's classical multi-hypothesis Chernoff bound. This quantity is defined as the minimum of the pairwise binary Chernoff divergences min_{j<k}C(\sigma_j,\sigma_k). It was known already that the optimal asymptotic rate must lie between C/3 and C, and that for certain classes of sets of states the bound is actually achieved. It was known to be achieved, in particular, when the state pair that is closest together in Chernoff divergence is more than 6 times closer than the next closest pair. Our results improve on this in two ways. Firstly, we show that the optimal asymptotic rate must lie between C/2 and C. Secondly, we show that the Chernoff bound is already achieved when the closest state pair is more than 2 times closer than the next closest pair. We also show that the Chernoff bound is achieved when at least r2r-2 of the states are pure, improving on a previous result by Nussbaum and Szko{\l}a. Finally, we indicate a number of potential pathways along which a proof (or disproof) may eventually be found that the multi-hypothesis quantum Chernoff bound is always achieved.Comment: 50 pages. v3: Slightly restructured, main results unchanged, connection to Barnum and Knill's result (arXiv:quant-ph/0004088) clarified. Accepted for JM

    EPR imaging study of paramagnetic centre distribution in thiokol-epoxy hermetics

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    The distribution of paramagnetic centres in carbon black filler in the interphase layer of the thiokol-epoxy hermetics on the border of brass or glass substrate was studied using EPR-imaging method. It was shown that the relative content of radicals decreases near the hermetic-"rigid" surface contact border. The thickness of the layer with a low concentration of radicals is estimated as 0.5±0.3 mm. The inhomogeneous distribution of radicals is more obvious in the case of hermetic hardening on a brass surface. These results are explained by a catalytic acceleration of the thiokol-epoxy polymerization reaction in the region of hermetic-metal surface contact. © 1996 Springer

    Proton NMR of water colloidal solutions of nanosized crystalline LaF3and LaF3: Gd3+ particles

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    © 2015 AIP Publishing LLC. A study of the nuclear magnetic relaxation of water protons in a series of colloidal solutions of nanosized lanthanum trifluoride and lanthanum fluoride particles, doped with gadolinium (0.5%). The proton NMR signal was recorded by a "Proton-20 M (Chromatech)" spectrometer. It is established that the rate of longitudinal relaxation depends on the nanoparticle concentration in the water solution, and on their dimension. It is demonstrated that the proton relaxation rate in the LaF3:Gd3+ solution increases with paramagnet concentration in the nanoparticles, and decreases with increasing particle size

    Smart Cities in Future Energy System Architecture

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    The article analyzes new technologies, which establish modern trends for future electric power systems operation and development, and their impact on production, storage, transmission, distribution and consumption of electricity. The article also studies trends and approaches to urban planning with an emphasis on energy infrastructure, where success in “smart city” and “smart grid” concepts implementation is considered as overarching question. The general requirements for smart power supply system are defined, problems that need to be solved are formulated, and a number of general recommendations are given for future development. Keywords: energy system, smart grid, smart cities JEL Classifications: L94; Q42; Q48; H5
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