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31.
Yury I. Lyakhovetsky Elena A. Shilova Boris L. Tumanskii Alexander V. Usatov Era A. Avetisyan Sergei R. Sterlin 《Fullerenes, Nanotubes and Carbon Nanostructures》2013,21(2):263-287
Abstract Both [60]- and [70]fullerene react with either the Scherer radical (perfluorodiisopropylethylmethyl, C9F19), a mixture of branched perfluorononenes (C9F18, the product of hexafluoropropene trimerization), or β-fluorosulphatotetrafluoroethyldiheptafluoroisopropylmethyl radical (C9F18OSO2F) in the ionization chamber of a mass spectrometer to give the positive parent ions of trifluoromethylation products, the reaction being accompanied by hydrogen addition. The reaction occurs at least partly on the walls of the ionization chamber, by a radical mechanism employing CF3 radicals formed from the radical reactants both thermally and under electron impact; only the latter route occurs with the perfluorononenes. 相似文献
32.
Giovanni Pizzi Dmitri Volja Boris Kozinsky Marco Fornari Nicola Marzari 《Computer Physics Communications》2014
BoltzWann is a code to evaluate thermoelectric and electronic transport properties of extended systems with a maximally-localized Wannier function basis set. The semiclassical Boltzmann transport equations for the homogeneous infinite system are solved in the constant relaxation-time approximation and band energies and band derivatives are obtained via Wannier interpolations. Thanks to the exponential localization of the Wannier functions obtained, very high accuracy in the Brillouin zone integrals can be achieved with very moderate computational costs. Moreover, the analytical expression for the band derivatives in the Wannier basis resolves any issues that may occur when evaluating derivatives near band crossings. We present here an updated version of the BoltzWann code, which is now fully integrated within Wannier90 version 2.0, with minor bug fixes and the possibility to study also two-dimensional systems. 相似文献
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34.
Andrey N. Agafonov Boris O. Volodkin Denis G. Kachalov Boris A. Knyazev Grigory I. Kropotov Konstantin N. Tukmakov 《Journal of Modern Optics》2013,60(11):1051-1054
AbstractWe demonstrate results of studies of a silicon binary diffractive optical element (DOE) focusing a terahertz laser Gaussian beam into a paraxial segment. The characteristics of the DOE were examined on a Novosibirsk Free Electron Laser beam of 141-μm wavelength. 相似文献
35.
Béatrice Fuster Deborah Houssin-Agbomson Simon Jallais Elena Vyazmina Guy Dang-Nhu Gilles Bernard-Michel Mike Kuznetsov Vladimir Molkov Boris Chernyavskiy Volodymyr Shentsov Dmitry Makarov Randy Dey Philip Hooker Daniele Baraldi Evelyn Weidner Daniele Melideo Valerio Palmisano Alexandros Venetsanos Jan Der Kinderen 《International Journal of Hydrogen Energy》2017,42(11):7600-7607
Hydrogen energy applications often require that systems are used indoors (e.g., industrial trucks for materials handling in a warehouse facility, fuel cells located in a room, or hydrogen stored and distributed from a gas cabinet). It may also be necessary or desirable to locate some hydrogen system components/equipment inside indoor or outdoor enclosures for security or safety reasons, to isolate them from the end-user and the public, or from weather conditions.Using of hydrogen in confined environments requires detailed assessments of hazards and associated risks, including potential risk prevention and mitigation features. The release of hydrogen can potentially lead to the accumulation of hydrogen and the formation of a flammable hydrogen-air mixture, or can result in jet-fires. Within Hyindoor European Project, carried out for the EU Fuel Cells and Hydrogen Joint Undertaking safety design guidelines and engineering tools have been developed to prevent and mitigate hazardous consequences of hydrogen release in confined environments. Three main areas are considered: Hydrogen release conditions and accumulation, vented deflagrations, jet fires and including under-ventilated flame regimes (e.g., extinguishment or oscillating flames and steady burns). Potential RCS recommendations are also identified. 相似文献
36.
This paper develops adaptive state feedback control schemes for a class of linear systems with state delay in the presence of unknown actuator failures. The main contributions of this paper are the development of two controller parametrizations which attempt to anticipate the future states, the introduction of an appropriate Lyapunov–Krasovskii type functional to design the new class of adaptation algorithms, and a stability proof. 相似文献
37.
Aquifers used for the production of drinking water are increasingly being used for the generation of shallow geothermal energy. This causes temperature perturbations far beyond the natural variations in aquifers and the effects of these temperature variations on groundwater quality, in particular trace elements, have not been investigated. Here, we report the results of column experiments to assess the impacts of temperature variations (5°C, 11°C, 25°C and 60°C) on groundwater quality in anoxic reactive unconsolidated sandy sediments derived from an aquifer system widely used for drinking water production in the Netherlands. Our results showed that at 5 °C no effects on water quality were observed compared to the reference of 11°C (in situ temperature). At 25°C, As concentrations were significantly increased and at 60 °C, significant increases were observed pH and DOC, P, K, Si, As, Mo, V, B, and F concentrations. These elements should therefore be considered for water quality monitoring programs of shallow geothermal energy projects. No consistent temperature effects were observed on Na, Ca, Mg, Sr, Fe, Mn, Al, Ba, Co, Cu, Ni, Pb, Zn, Eu, Ho, Sb, Sc, Yb, Ga, La, and Th concentrations, all of which were present in the sediment. The temperature-induced chemical effects were probably caused by (incongruent) dissolution of silicate minerals (K and Si), desorption from, and potentially reductive dissolution of, iron oxides (As, B, Mo, V, and possibly P and DOC), and mineralisation of sedimentary organic matter (DOC and P). 相似文献
38.
Graphene: Sub‐Terahertz Frequency‐Domain Spectroscopy Reveals Single‐Grain Mobility and Scatter Influence of Large‐Area Graphene (Adv. Mater. 16/2015) 下载免费PDF全文
39.
Joseph Berry Tonio Buonassisi David A. Egger Gary Hodes Leeor Kronik Yueh‐Lin Loo Igor Lubomirsky Seth R. Marder Yitzhak Mastai Joel S. Miller David B. Mitzi Yaron Paz Andrew M. Rappe Ilan Riess Boris Rybtchinski Oscar Stafsudd Vladan Stevanovic Michael F. Toney David Zitoun Antoine Kahn David Ginley David Cahen 《Advanced materials (Deerfield Beach, Fla.)》2015,27(35):5102-5112
40.