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Isotropic covariance matrix functions on all spheres
(Springer International Publishing AG, 201508)This paper reviews and introduces characterizations of the covariance function on all spheres that is isotropic and continuous, and characterizations of the covariance matrix function on all spheres whose entries are ... 
FischerTropsch synthesis: Effect of ammonia in syngas on the FischerTropsch synthesis performance of a precipitated iron catalyst
(Elsevier B.V., 201506)The effect of ammonia in syngas on the FischerTropsch synthesis (FTS) reaction over 100Fe/5.1Si/2.0Cu/3.0K catalyst was studied at 220270 degrees C and 1.3 MPa using a 1L slurry phase reactor. The ammonia added in syngas ... 
FischerTropsch synthesis: Effects of hydrohalic acids in syngas on a precipitated iron catalyst
(American Chemical Society, 201505)The current investigation was undertaken to identify limits of hydrohalic acid (HX, X = F, Cl, Br) impurities in syngas and shed light on the mechanism of FIX poisoning of a 100 Fe/5.1 Si/2 Cu/3 K FTS catalyst under ... 
Multifractional vector Brownian motions, their decompositions, and generalizations
(Taylor & Francis Group, 20150504)This article introduces three types of covariance matrix structures for Gaussian or elliptically contoured vector random fields in space and/or time, which include fractional, bifractional, and trifractional vector Brownian ... 
Logistic vector random fields with logistic direct and cross covariances
(Elsevier B.V., 201506)The logistic vector random field is introduced in this paper as a scale mixture of Gaussian vector random fields, and is thus a particular elliptically contoured (spherically invariant) vector random field. Such a logistic ... 
Increasing stability for the inverse problem of the Schrodinger equation with the partial Cauchy data
(American Institute of Mathematical Sciences, 201505)To show increasing stability in the problem of recovering potential c is an element of C1 (Omega) in the Schrodinger equation with the given partial Cauchy data when energy frequency k is growing, we will obtain some ... 
Zeta function of selfadjoint operators on surfaces of revolution
(IOP Publishing, 20150410)In this article we analyze the zeta function for the Laplace operator on a surface of revolution. A variety of boundary conditions, separated and unseparated, are considered. Formulas for several residues and values of the ... 
Stellar models of multiple populations in globular clusters  I. The main sequence of NGC 6752
(Oxford University Press, 20150111)We present stellar atmosphere and evolution models of mainsequence stars in two stellar populations of the Galactic globular cluster NGC 6752. These populations represent the two extremes of lightelement abundance ... 
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. ...