Bowling Green State University

About: Bowling Green State University is a education organization based out in Bowling Green, Ohio, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 8315 authors who have published 16042 publications receiving 482564 citations. The organization is also known as: BGSU.

A Cenozoic diffuse alkaline magmatic province (DAMP) in the Southwest Pacific without rift or plume origin

Abstract: [1] Common geological, geochemical, and geophysical characteristics of continental fragments of East Gondwana and adjacent oceanic lithosphere define a long-lived, low-volume, diffuse alkaline magmatic province (DAMP) encompassing the easternmost part of the Indo-Australian Plate, West Antarctica, and the southwest portion of the Pacific Plate. A key to generating the Cenozoic magmatism is the combination of metasomatized lithosphere underlain by mantle at only slightly elevated temperatures, in contrast to large igneous provinces where mantle temperatures are presumed to be high. The SW Pacific DAMP magmatism has been conjecturally linked to rifting, strike-slip faulting, mantle plumes, or hundreds of hot spots, but all of these associations have flaws. We suggest instead that sudden detachment and sinking of subducted slabs in the late Cretaceous induced Rayleigh-Taylor instabilities along the former Gondwana margin that in turn triggered lateral and vertical flow of warm Pacific mantle. The interaction of the warm mantle with metasomatized subcontinental lithosphere that characterizes much of the SW Pacific DAMP concentrates magmatism along zones of weakness. The model may also provide a mechanism for warming south Pacific mantle and resulting Cenozoic alkaline magmatism, where the oceanic areas are characterized primarily, but not exclusively, by short-lived hot spot tracks not readily explained by conventional mantle plume theory. This proposed south Pacific DAMP is much larger and longer-lived than previously considered.

Assessing evolutionary epistemology

Abstract: There are two interrelated but distinct programs which go by the name “evolutionary epistemology” One attempts to account for the characteristics of cognitive mechanisms in animals and humans by a straightforward extension of the biological theory of evolution to those aspects or traits of animals which are the biological substrates of cognitive activity, eg, their brains, sensory systems, motor systems, etc (EEM program) The other program attempts to account for the evaluation of ideas, scientific theories and culture in general by using models and metaphors drawn from evolutionary biology (EET program) The paper begins by distinguishing the two programs and discussing the relationship between them The next section addresses the metaphorical and analogical relationship between evolutionary epistemology and evolutionary biology Section IV treats the question of the locus of the epistemological problem in the light of an evolutionary analysis The key questions here involve the relationship between evolutionary epistemology and traditional epistemology and the legitimacy of evolutionary epistemology as epistemology Section V examines the underlying ontological presuppositions and implications of evolutionary epistemology Finally, section VI, which is merely the sketch of a problem, addresses the parallel between evolutionary epistemology and evolutionary ethics

Stark Effects after Excited-State Interfacial Electron Transfer at Sensitized TiO2 Nanocrystallites

Abstract: Photophysical studies were performed with [Ru(dtb)(2)(dcb)](PF(6))(2) and cis-Ru(dcb)(dnb)(NCS)(2,) where dtb is 4,4'-(C(CH(3))(3))(2)-2,2'-bipyridine, dcb is 4,4'-(COOH)(2)-2,2'-bipyridine, and dnb is 4,4'-(CH(3)(CH(2))(8))(2)-2,2'-bipyridine), anchored to anatase TiO(2) particles ( approximately 15 nm in diameter) interconnected in a mesoporous, 10 mum thick film immersed in Li(+)-containing CH(3)CN electrolytes with iodide or phenothiazine donors. Pulsed-laser excitation resulted in rapid excited-state injection and donor oxidation to yield TiO(2)(e(-))s and oxidized donors, while the metal-to-ligand charge-transfer (MLCT) absorption spectrum of the Ru(II) coordination compounds differed from that which was initially excited. The spectral data were consistent with an underlying Stark effect and indicated that the surface electric field was not completely screened from the molecular sensitizer. The magnitude of the electric field was estimated to be approximately 270 MV/m from Li(+) titration experiments, corresponding to a approximately 40 mV potential drop. With iodide donors, the amplitude of the Stark effect decreased over time periods where charge recombination was absent, behavior attributed to "screening" of the electric field by interfacial ionic reorganization. The screening kinetics were nonexponential but were well described by the Kohlrausch-Williams-Watts model, from which a characteristic rate constant, tau(o)(-1), of approximately 1.5 x 10(5) s(-1) was abstracted. At least seven other sensitizers and five different cations, as well as on SnO(2) nanoparticle films, exhibited similar transient absorption behavior with iodide donor molecules indicating that the effect was quite general. In the presence of phenothiazine donors (or in the absence of an external donor), there was no clear evidence for screening, and the Stark effect disappeared concurrent with interfacial charge recombination. Complementary spectroelectrochemical studies of these same sensitized films displayed similar absorption spectra when the TiO(2) thin film was partially reduced with a forward bias. Spectral modeling in the absence of donor molecules as well as studies of TiO(2) thin films sensitized with two different Ru(II) compounds demonstrated that the electric field created by excited-state injection from one sensitizer influenced the absorption spectra of other sensitizers that had not undergone photoinduced electron injection.