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91.
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This paper introduces an effectively mesh‐independent and computationally efficient model for CO2 leakage through wellbores. A one‐dimensional compressible two‐fluid domain, representing a homogeneous air gas and a multiphase CO2 with a jump at the interface between them, is modeled. The physical domain is modeled using the drift‐flux model, and the governing equations are solved using a mixed finite‐element discretization scheme. The standard Galerkin FEM, the partition of unity method, and the level‐set method are integrated to solve the problem. All important physical phenomena and processes occurring along the wellbore path, including fluid dynamics, buoyancy, phase change, compressibility, thermal interaction, wall friction, and slip between phases, together with the jump in density and enthalpy between air and CO2, are considered. Two numerical examples illustrating the computational capability and efficiency of the model are presented. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
93.
94.
V.S.M. Barros W.M. de Azevedo H.J. Khoury M.E.A. Andrade P. Linhares Filho 《Radiation measurements》2010,45(3-6):435-437
In this work, α-Al2O3 doped either with Tb3+ or Tm3+ was prepared by combustion synthesis techniques for thermoluminescent (TL) ionizing radiation dosimetry applications. In this method, the reactants (aluminum nitrate, urea and therbium or thulium nitrate) are ignited in a muffle furnace at temperatures as low as 500 °C. This synthesis route is an alternative technique to the conventional fabrication methods of materials based on α-Al2O3 (Czochralsky, Vernuil), where high melting temperatures and reducing atmospheres are required. After combustion, the samples were annealed at temperatures ranging from 1000 to 1400 °C for 4 h in order to obtain the pure α-phase structure and were then irradiated with a Co-60 gamma radiation source. The annealed samples present a well defined TL glow peak with a maximum at approximately 200 °C and linear TL response in the dose range 0.5–5 Gy. It was observed that a 0.1 mol% concentration of Tb3+ or Tm3+ and annealing at 1400 °C optimize the TL sensitivity. The highest sensitivity was found for Tm3+ doped samples which were approximately 25 times more sensitive than Tb3+ doped samples. These results strongly suggest that combustion synthesis is a suitable technique to prepare doped aluminum oxide material and that Tm3+ doped aluminum oxide is a potential material for TL radiation dosimetry. 相似文献
95.
B.?Beck S.?Srivastava K.?Khoury E.?Herdtweck Alexander?D?mling 《Molecular diversity》2010,14(3):479-491
We designed two novel thiolactone scaffolds. Both scaffolds can be accessed by a convergent Ugi multicomponent reaction (MCR)
and are, thus, amenable to library synthesis. Design, stereoselectivity, structures, full experimental details, and virtual
libraries will be reported. 相似文献
96.
We use a photon-number-resolving detector to monitor the photon-number distribution of the output of an interferometer, as a function of phase delay. As inputs we use coherent states with mean photon number up to seven. The postselection of a specific Fock (photon-number) state effectively induces high-order optical nonlinearities. Following a scheme by Bentley and Boyd [Opt. Express 12, 5735 (2004).10.1364/OPEX.12.005735], we explore this effect to demonstrate interference patterns a factor of 5 smaller than the Rayleigh limit. 相似文献
97.
The bunching of two single photons on a beam splitter is a fundamental quantum effect, first observed by Hong, Ou, and Mandel. It is a unique interference effect that relies only on the photons' indistinguishability and not on their relative phase. We generalize this effect by demonstrating the bunching of two Bell states, created in two passes of a nonlinear crystal, each composed of two photons. When the two Bell states are indistinguishable, phase-insensitive destructive interference prevents the outcome of fourfold coincidence between the four spatial-polarization modes. For certain combinations of the two Bell states, we demonstrate the opposite effect of antibunching. We relate this result to the number of distinguishable modes in parametric down-conversion. 相似文献
98.
Khoury J Drehman A Woods CL Haji-Saeed B Sengupta SK Goodhue W Kierstead J 《Optics letters》2006,31(6):808-810
A new, optically addressed deformable mirror device is demonstrated. The device consists of a pixellated metalized polymeric membrane mirror supported above an optically addressed photoconductive substrate. A conductive transparent ZnO layer is deposited on the back side of the substrate. A very high-frequency AC bias is applied between the membrane and the back electrode of the device. The membrane is deformed when the back of the device is illuminated because of impedance and bias redistribution between two cascaded impedances. We fabricated, demonstrated, and modeled the operation of this device. 相似文献
99.
Successful completion of the Human Genome Project has raised public expectations that research findings will translate quickly into health benefits; however, the gap between biomedical research and clinical and public health application seems wider than ever. Public health scientists now have the opportunity to help create a broad concept of research translation that integrates genomic information into policies, programs and services benefiting the whole population. Important 'signposts' along the translation highway include conducting population-based research in genomics, developing evidence on the clinical and public health value of genomic information, and integrating genomics into health practice. 相似文献
100.