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FischerTropsch synthesis: activity and selectivity of chiFe5C2 and circle minusFe3C carbides
(American Chemical Society, 20140810)Two different iron carbides, Hägg (χFe5C2) and cementite (ϴFe3C) for FischerTropsch synthesis (FTS) was investigated. Both iron carbides were oxidized to Fe3O4 during FTS. Hägg carbide (χFe5C2), initially exhibits ... 
Hspaces, loop spaces and the space of positive scalar curvature metrics on the sphere
(Mathematical Sciences Publishers, 20141002)For dimensions n >= 3, we show that the space Riem(+)(Sn) of metrics of positive scalar curvature on the sphere Sn is homotopy equivalent to a subspace of itself which takes the form of an Hspace with a homotopy ... 
The space of positive scalar curvature metrics on a manifold with boundary
(20141112)We study the space of Riemannian metrics with positive scalar curvature on a compact manifold with boundary. These metrics extend a fixed boundary metric and take a product structure on a collar neighbourhood of the boundary. ... 
Increasing stability for determining the potential in the Schrodinger equation with attenuation from the DirichlettoNeumann map
(American Institute of Mathemaical Sciences, 201411)We derive some bounds which can be viewed as an evidence of increasing stability in the problem of recovering the potential coefficient in the Schrodinger equation from the DirichlettoNeumann map in the presence of ... 
Recovery of time dependent volatility coefficient by linearization
(American Institute of Mathematical Sciences, 201403)We study the problem of reconstruction of special time dependent local volatility from market prices of options with different strikes at two expiration times. For a general diffusion process we apply the linearization ... 
Structural analysis and cations distribution of nanocrystalline Ni1xZnxFe1.7Ga0.3O4
(Elsevier B.V., 20140909)Nanostructured Ni1xZnxFe1.7Ga0.3O4, with x = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5 were prepared by citrate method and were investigated using Xray diffraction and Mossbauer spectroscopy. The structure characterized using Xray ... 
Improved asymptotics of a decreasing mean residual life estimator
(Taylor & Francis Group, 20140917)The mean residual life of a life distribution, X, with a finite mean is defined by M(t) = E[X  tX > t] for t > 0. Kochar etal. (2000) provided an estimator of M when it is assumed to be decreasing. They showed that its ... 
Applications of the hCobordism Theorem
(Wichita State University, 201405)We provide an exposition of J. Milnor's proof of the hCobordism Theorem. This theorem states that a smooth, compact, simply connected ndimensional manifold W with n greater than or equal to 6, whose boundary boundaryW ... 
Geometry of horizontal bundles and connections
(Wichita State University, 201405)An Ehresmann connection on a fiber bundle pi: E > M is defined by prescribing a suitable horizontal subbundle H of the tangent bundle piT: TE > E. For a horizontal bundle to be suitable, it must have a property called ... 
Isochrones for old (> 5 GYR) stars and stellar populations. I. models for2.4 <= [Fe/H] <=+0.6, 0.25 <= Y <= 0.33, and0.4 <= [alpha/Fe] <=+0.4
(IOP Publishing, 20141010)Canonical grids of stellar evolutionary sequences have been computed for the helium massfraction abundances Y = 0.25, 0.29, and 0.33, and for iron abundances that vary from 2.4 to +0.4 (in 0.2 dex increments) when [alpha/Fe] ... 
FischerTropsch synthesis: morphology, phase transformation, and carbonlayer growth of ironbased catalysts
(John Wiley & Sons, Inc., 201407)The morphological, phase transformations and carbonlayer growth for unpromoted and Kpromoted iron catalysts were investigated over time during FischerTropsch synthesis. Catalysts were activated in CO for 24 h, which ... 
FischerTropsch synthesis: deactivation as a function of potassium promoter loading for precipitated iron catalyst
(Springer, 201410)The effect of potassium promoter loading (0, 0.5, 1.0 and 2.0 atomic ratio) on the performance of precipitated iron catalysts was investigated during FischerTropsch synthesis using a continuously stirred tank reactor. ... 
Horizontal bundles and connections
(Wichita State University. Graduate School, 20140425)A manifold is a mathematical space that locally resembles standard Euclidean space. In order to study the geometry of such a space, it is necessary to prescribe a connection on the manifold. A connection describes how ... 
FischerTropsch synthesis: effect of activation gas after varying Cu promoter loading over Kpromoted Febased catalyst
(© Springer, 201409)The effects of activation gas and copper promoter loading on the FischerTropsch synthesis performance of potassium promoted precipitated ironbased catalysts were investigated using a continuously stirred tank reactor. ... 
Measurement of charged pion production yields off the NuMI target
(American Physical Society, 201409)The fixedtarget Main Injector Particle Production (MIPP) experiment, Fermilab E907, was designed to measure the production of hadrons from the collisions of hadrons of momenta ranging from 5 to 120 GeV/c on a variety of ... 
Synthesis of highly ordered 30 nm NiFe2O4 particles by the microwavecombustion method
(Elsevier B.V., 201411)NiFe2O4 of 30 nm average size was synthesized by microwave combustion and subsequent solid state reaction at 1273 K. The materials were characterized by Xray diffraction, TEM, vibrating sample magnetometery and Mossbauer ... 
Point vortex model for asymmetric inviscid wakes past bluff bodies
(IOP Publishing, 20140527)Wakes past bluff bodies are modeled by means of point vortices standing in equilibrium. The consistency of the adopted model is discussed with respect to the asymptotic model proposed by Batchelor. It is shown that, in ... 
Spectra of unitary integral operators on L2 (R) with kernels k(xy)
(World Scientific, 2013)Unitary integral transforms play an important role in mathematical physics. A primary example is the Fourier transform whose kernel is of the form k(x, y) = k(xy), i.e., of the product type. Here we consider the determination ... 
Some observations regarding steady laminar flows past bluff bodies
(Royal Society, 20140728)Steady laminar flows past simple objects, such as a cylinder or a sphere, have been studied for well over a century. Theoretical, experimental and numerical methods have all contributed fundamentally towards our understanding ... 
Examples of discontinuity for the variational solution of the minimal surface equation with Dirichlet data on a domain with a nonconvex corner and locally negative mean curvature
(Wichita State University, 201312)The purpose of this thesis is to investigate the role of smoothness, specifically the smoothness of the boundary ∂Ω, in the behavior of the variational solution f on a domain Ω to the Dirichlet problem for the Minimal ...