Texas Christian University

About: Texas Christian University is a education organization based out in Fort Worth, Texas, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 3245 authors who have published 8258 publications receiving 282216 citations. The organization is also known as: TCU & Texas Christian University, TCU.

Silicon-micromachined gas chromatography system used to separate and detect ammonia and nitrogen dioxide. I. Design, fabrication, and integration of the gas chromatography system

Abstract: A miniature gas chromatography (GC) system was designed and developed using silicon micromachining and integrated circuit (IC) processing techniques. The micromachined gas chromatography (MMGC) system is composed of a miniature sample injector incorporating a 10-/spl mu/m-long sample loop; a 0.9-m-long, rectangular-shaped (300 /spl mu/m width and 10 /spl mu/m height) capillary column coated with a 0.2-/spl mu/m-thick copper phthalocyanine (CuPc) stationary phase, and a dual-detector scheme based upon a CuPc-coated chemiresistor and a 125-/spl mu/m-diameter thermal conductivity detector (TCD) bead. Silicon micromachining was employed to fabricate the interface between the sample injector and the GC column, the GC column itself, and the dual-detector cavity. A novel processing technique was developed to sublime a homogeneous CuPc stationary-phase coating on the GC column walls. The complete MMGC system package is approximately 4 in, square and 100 mils (2.5 mm) thick, [96]. >

Behavioural research in logistics and supply chain management

Abstract: Purpose – This paper aims to advocate and facilitate undertaking research focused on the effects of human behaviour, judgment and decision making in logistics and supply chain management (SCM).Design/methodology/approach – In addition to providing an overview of the potential benefits of behavioural research, this paper presents two modified frameworks for identifying and addressing behavioural issues in logistics and SCM.Findings – Behavioural research can significantly advance both theory and practice in logistics and SCM. Little behavioural research appears in top logistics journals. As researchers begin to conduct more such projects, knowledge pertaining to issues of importance to logistics and SCM will be created.Originality/value – This paper highlights an important research area and a methodology, (controlled behavioural experiments), that are currently underutilized in logistics and SCM. It further presents potential research questions and suggestions for ways in which interested researchers could...

Were aspects of Pan-African deformation linked to Iapetus opening?

Abstract: The convergence recorded in some Pan-African deformational belts (sensu lato) in South America, Africa, Madagascar, southern India, Sri Lanka, and Antarctica is temporally correlated with opening of the Iapetus ocean. We propose a model in which continent-continent collision and closure of the Adamastor ocean between the Amazon–West African–Rio de La Plata cratons and the Sao Francisco–Congo–Kalahari cratons in the late Neoproterozoic are linked to rifting and orthogonal spreading between Laurentia and the South American cratons. By the Early Cambrian, the cratons in South America and Africa were assembled as West Gondwana. Closure of the Mozambique ocean, which appears to have extended across Antarctica between Lutzow-Holm Bay and the Shackleton Range, resulted in continued convergence between the Congo–Kalahari–Queen Maud Land block and East Gondwana in the Cambrian. Coeval deformation in the Transantarctic Mountains may be related to the obliquity of the Antarctic margin relative to Iapetus spreading directions. Initiation of voluminous arc magmatism along the paleo-Pacific margin of Gondwana in the Early Cambrian is broadly synchronous with the cessation of intra-Gondwana Pan-African deformation, possibly reflecting a change in plate motions at the time of final Gondwana assembly. The new subduction regime along the Gondwana margin in the Early Cambrian may be linked to the closure of the Iapetus ocean basin.

The age–metallicity structure of the Milky Way disc using APOGEE

Abstract: The measurement of the structure of stellar populations in the Milky Way disc places fundamental constraints on models of galaxy formation and evolution. Previously, the disc’s structure has been studied in terms of populations defined geometrically and/or chemically, but a decomposition based on stellar ages provides a more direct connection to the history of the disc, and stronger constraint on theory. Here, we use positions, abundances and ages for 31 244 red giant branch stars from the Sloan Digital Sky Survey (SDSS)-APOGEE survey, spanning 3 < Rgc < 15 kpc, to dissect the disc into mono-age and mono-[Fe/H] populations at low and high [α/Fe]. For each population, with age < 2 Gyr and [Fe/H] < 0.1 dex, we measure the structure and surface-mass density contribution. We find that low [α/Fe] mono-age populations are fit well by a broken exponential, which increases to a peak radius and decreases thereafter. We show that this profile becomes broader with age, interpreted here as a new signal of disc heating and radial migration. High [α/Fe] populations are well fit as single exponentials within the radial range considered, with an average scalelength of 1.9 ± 0.1 kpc. We find that the relative contribution of high to low [α/Fe] populations at R0 is f� = 18 per cent ± 5 per cent; high [α/Fe] contributes most of the mass at old ages, and low [α/Fe] at young ages. The low and high [α/Fe] populations overlap in age at intermediate [Fe/H], although both contribute mass at R0 across the full range of [Fe/H]. The mass-weighted scaleheight hZ distribution is a smoothly declining exponential function. High [α/Fe] populations are thicker than low [α/Fe], and the average hZ increases steadily with age, between 200 and 600 pc.