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Petrology of the Eocene Marquez Shale Member of the Reklaw Formation, Bastrop County, Texas
The Eocene Marquez Shale, a member of the Reklaw Formation, was studied in Bastrop County, Texas, where a complete section crops out. The unit consists of (1) lignitic, pyritic fissile claystones; (2) glauconitic fossiliferous bioturbated mudstones; (3) plant-rich, laminated, slightly rippled interbedded siltstones and mudstones; and (4) small pyrite concretions, large septarian siderite concretions, and cone-in-cone structures. The dominant clay mineral is smectite, with some intermixed kaolinite. Silt-size material includes abundant quartz, and rarer feldspar and muscovite. Glauconite, in the form of pellets, occurs in the lower Marquez, often in great abundance. Marine fossils, especially mollusks and foraminifera, are also common in the lower Marquez. Plant fragments and amorphous organic material are present throughout. Pyrite is associated with marine fossils, plant fragments and organic matter, glauconite, and concretions, and is usually framboidal. Weathering products include gypsum and hematite. The depositional setting of the lower Marquez fluctuated between a stagnant, brackish swamp or lagoon, and an oxygenated, open marine, shallow shelf area. The upper Marquez was probably delta-influenced, being perhaps an interdeltaic or interdistributary embayment.Geological Science
Implications of rotationâinversionâpermutation invariance for analytic molecular potential energy surfaces
A molecular potential energy surface has the symmetry properties of invariance to rotation of the whole molecule, inversion of all atomic coordinates, and permutation of indistinguishable nuclei. While some of this invariance character can be easily incorporated in a local description of the surface, a formal application of these symmetry restrictions is useful in considering the form of the globalsurface which must account for large amplitude changes of the atomic coordinates. The form of a global molecular potential energy surface as a properly symmetrized analytic function of Cartesian coordinates is derived by extending Molienâs theorem of invariants for finite groups to cover the continuous rotationâinversion group. O(3), and the product of O(3) with the complete nuclear permutation group. The role of soâcalled redundant internal coordinates in molecular potential energy surfaces is clarified
Can the Type-IIB axion prevent Pre-big Bang inflation?
We look at the possibility of superinflationary behavior in a class of
anisotropic Type-IIB superstring cosmologies in the context of Pre-big Bang
scenario and find that there exists a rather narrow range of parameters for
which these models inflate. We then show that, although in general this
behavior is left untouched by the introduction of a Ramond-Ramond axion field
through a SL(2,R) rotation, there exists a particular class of axions for which
inflation disappears completely. Asymptotic past initial conditions are briefly
discussed, and some speculations on the possible extension of Pre-big Bang
ideas to gravitational collapse are presented.Comment: harvmac, epsf. 3 figures include
Adult Learning and the Shrinking Globe
The purpose of this roundtable is to explore the evolution of Adult Education in several European nations relative to the United States and the advantages of the broadened European vision of adult learning as lifelong-lifewide. Through examining these practices we may discover options for inclusion in the United States
Quark Effects in the Gluon Condensate Contribution to the Scalar Glueball Correlation Function
One-loop quark contributions to the dimension-four gluon condensate term in
the operator product expansion (OPE) of the scalar glueball correlation
function are calculated in the MS-bar scheme in the chiral limit of quark
flavours. The presence of quark effects is shown not to alter the cancellation
of infrared (IR) singularities in the gluon condensate OPE coefficients. The
dimension-four gluonic condensate term represents the leading power corrections
to the scalar glueball correlator and, therein, the one-loop logarithmic
contributions provide the most important condensate contribution to those QCD
sum-rules independent of the low-energy theorem (the subtracted sum-rules).Comment: latex2e, 6 pages, 7 figures embedded in latex fil
Design optimisation of air-fed full pressurised suits
This article is a post-print version of the published article which may be accessed at the link below.The JET machine and associated facilities require significant maintenance and enhancement installation activities in support of the experimental exploitation programme. A proportion of these activities are within radiological and respiratory hazardous environments. As such, breathing air-fed one-piece pressurised suits provide workers with protection from the inhalation of both airborne tritium and beryllium dust. The design of these suits has essentially developed empirically. There is a practical necessity to improve the design to optimise worker performance, protection and thermal comfort. This paper details the complexity of modeling the three-dimensional thermofluid domain between the inner surface of the suit and under garments that includes mass as well as heat transfer, suiting geometry, human metabolism and respiration and effects of limb movements. The methods used include computational fluid dynamics (CFD), theoretical adaptations of mixed-phase turbulent flow, profile scanning of a suit and actuating life size mannequin and data processing of the images and experimental validation trials. The achievements of the current programme and collaborations are presented in the paper and future endeavors are discussed.The author gratefully acknowledges the loan of the articulated mannequin from the Defence Science and Technology Laboratories. This work was funded jointly by EPSRC and by the European Communities under the contract of Association between EURATOM and UKAEA. The views and opinions expressed herein do not necessarily reflect those of the European Commission. This work was carried out within the framework of EFDA
NLO prescription for unintegrated parton distributions
We show how parton distributions unintegrated over the parton transverse
momentum, k_t, may be generated, at NLO accuracy, from the known integrated
(DGLAP-evolved) parton densities determined from global data analyses. A few
numerical examples are given, which demonstrate that sufficient accuracy is
obtained by keeping only the LO splitting functions together with the NLO
integrated parton densities. However, it is important to keep the precise
kinematics of the process, by taking the scale to be the virtuality rather than
the transverse momentum, in order to be consistent with the calculation of the
NLO splitting functions.Comment: 20 pages, 8 figures. v2: version to appear in Eur. Phys. J.
Synthesis for Polynomial Lasso Programs
We present a method for the synthesis of polynomial lasso programs. These
programs consist of a program stem, a set of transitions, and an exit
condition, all in the form of algebraic assertions (conjunctions of polynomial
equalities). Central to this approach is the discovery of non-linear
(algebraic) loop invariants. We extend Sankaranarayanan, Sipma, and Manna's
template-based approach and prove a completeness criterion. We perform program
synthesis by generating a constraint whose solution is a synthesized program
together with a loop invariant that proves the program's correctness. This
constraint is non-linear and is passed to an SMT solver. Moreover, we can
enforce the termination of the synthesized program with the support of test
cases.Comment: Paper at VMCAI'14, including appendi
Ion adsorption-induced wetting transition in oil-water-mineral systems
The relative wettability of oil and water on solid surfaces is generally governed by a complex competition of molecular interaction forces acting in such three-phase systems. Herein, we experimentally demonstrate how the adsorption of in nature abundant divalent Ca2+ cations to solid-liquid interfaces induces a macroscopic wetting transition from finite contact angles (â10°) with to near-zero contact angles without divalent cations. We developed a quantitative model based on DLVO theory to demonstrate that this transition, which is observed on model clay surfaces, mica, but not on silica surfaces nor for monovalent K+ and Na+ cations is driven by charge reversal of the solid-liquid interface. Small amounts of a polar hydrocarbon, stearic acid, added to the ambient decane synergistically enhance the effect and lead to water contact angles up to 70° in the presence of Ca2+. Our results imply that it is the removal of divalent cations that makes reservoir rocks more hydrophilic, suggesting a generalizable strategy to control wettability and an explanation for the success of so-called low salinity water flooding, a recent enhanced oil recovery technology
Local dynamics and gravitational collapse of a self-gravitating magnetized Fermi gas
We use the Bianchi-I spacetime to study the local dynamics of a magnetized
self-gravitating Fermi gas. The set of Einstein-Maxwell field equations for
this gas becomes a dynamical system in a 4-dimensional phase space. We consider
a qualitative study and examine numeric solutions for the degenerate zero
temperature case. All dynamic quantities exhibit similar qualitative behavior
in the 3-dimensional sections of the phase space, with all trajectories
reaching a stable attractor whenever the initial expansion scalar H_{0} is
negative. If H_{0} is positive, and depending on initial conditions, the
trajectories end up in a curvature singularity that could be isotropic(singular
"point") or anisotropic (singular "line"). In particular, for a sufficiently
large initial value of the magnetic field it is always possible to obtain an
anisotropic type of singularity in which the "line" points in the same
direction of the field.Comment: 6 pages, 3 figures (accepted in General Relativity and Gravitation
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