Authors:L. L. A. Vermeersen, R. Riva, and R. Sabadini
The 3D quasi-static displacements during and following an earthquake provide a wealth of information on the internal structure and rheological properties of the Earth. If an earthquake occurs in a region that has shallow-viscosity zones inside the crust or at the top of the mantle (asthenosphere), then post-seismic displacements of the crust on the order of millimeters per year are possible. These can be detected by means of permanent GPS stations in the years following a faulting event. In this paper we systematically study the influence of viscoelastic simulation model restrictions on co- and post-seismic deformation. Examples include stratification of the Earth model, modeling of the seismic source, influence of compressibility, effects of position and viscosities of shallow low-viscosity layers. It will be shown that some of these model restrictions or assumptions can have non-negligible influences on the simulated 3D co- and post-seismic displacements.
Authors:A. Rivas, D. Deshler, R. Colle, R. González, and F. Quimby
Two indicators regarded to reflect the status of disciplinary differentiation were assessed through citation analysis. Adoption of scientific innovations (publications utilizing new scientific information) and interdisciplinary linkages (percentage of total publications of single disciplines which are cross-referenced by other disciplines) were investigated in selected biological professions. Findings indicated: 1) a significant delay in the use of innovations and a significant difference in the emphasis of interdisciplinary linkages in several professions and disciplines; 2) faster adoption of innovations and greater interdisciplinary linkages in areas with broader disciplinary contents; 3) an inter-personal communication pattern; and 4) slower adoption in applied than in basic fields.
Authors:J. I. Gutiérrez-Ortiz, B. de Rivas, R. López-Fonseca, and J. R. González-Velasco
Summary The catalytic properties of ceria-zirconia mixed oxides have been characterized using temperature-programmed techniques such as temperature-programmed desorption of ammonia and water, and temperature-programmed reduction with hydrogen. The acidity and hydrophobicity of these materials increased with zirconia content while the reducibility was maximum for Ce0.5Zr0.5O2 sample.
Authors:A. Rivas, J. Deshler, F. Quimby, H. Mohammed, D. Wilson, R. Gonzalez, D. Lein, and P. Bruso
Interdisciplinary synthesis and validity analysis (ISVA), a structured learning approach which integrates learning and communication theories, meta-analytic evaluation methods,
and literature management-related technologies was applied in the context of the 1993–1997 bovine mastitis research literature.
This study investigated whether ISVA could: 1) facilitate the analysis and synthesis of interdisciplinary knowledge claims,
and 2) generate projects or research questions. The bovine mastitis-related literature was conceptualized as composed of microbiological,
immunological, and epidemiological dimensions. Keywords involving these dimensions were searched in theMedline andAgricola databases. A final list of 148 articles were retrieved, analyzed, synthesized into fifteen information sub-sets, and evaluated
for construct, internal, external and statistical validity through an interdisciplinary iterative dialogical process. Validity
threats were re-phrased as new research or educational projects.
Authors:J. Gutiérrez-Ortiz, Beatriz de Rivas, R. López-Fonseca, and J. González-Velasco
The catalytic behaviour of ceria, zirconia
and ceria–zirconia mixed oxides in the temperature-programmed degradation
of toluene and n-hexane was analysed by
means of evolved gas analysis (mass spectrometry). Pure cerium oxide resulted
the most active catalyst in the oxidation of both compounds. This fact revealed
the crucial role of the surface oxygen species in the decomposition of this
type of hydrocarbons. The low affinity of CeO2 for
H2O and CO2, the major oxidation
products, may be also responsible for the observed highly active catalytic
Authors:A. Rivas, D. Wilson, R. Gonzalez, H. Mohammed, F. Quimby, D. Lein, R. Milligan, R. Colle, J. Deshler, and W. Trochim
An interdisciplinary and systems-oriented approach for evaluation of academic programs was explored in veterinary research,
education and extension in the context of prevention of bovine mastitis. Bibliometric-based document analysis and observation
methods were used to assess disciplinary contents of veterinary research and graduate education theses, and New York State
dairy farmers' adoption rate of selected veterinary recommendations (bacteriological testing of raw milk, “closed herds”,
and three hygiene-related practices). Findings indicated that: a) the veterinary extension literature was lower in output
and less differentiated in disciplinary content than that of the agricultural counterpart; b) three disciplines accounted
for 85% of all theses major contents; and c) 39.7% of New York dairies requested bacteriological testing, 50% of investigated
dairies had “closed herds” and at least 9.4% of those did not adopt all the hygiene-related practices. Context-specific recommendations
are proposed. It is concluded that this evaluation approach may facilitate policy analysis, program development and may be
applicable to other academic settings.
Authors:J. M. Rivas Mercury, A. A. Cabral, A. E. M. Paiva, R. S. Angélica, R. F. Neves, and T. Scheller
This article studied the thermal behavior and the evolution of the crystalline phases with temperature of the red mud (bauxite tailing) from an aluminum industry at Maranhão, North-Northwestern Brazil. The experiments were carried out by Field Emission Scanning Electron Microscopy (FE-SEM), Simultaneous Thermal Analysis (TG–DSC), Optical Dilatometry up to 1623 K, and X-ray diffraction (XRD) of previously heated samples between 523 and 1523 K. The crystalline phases and the amorphous contents were quantified on raw and heated samples (at 1523 K) according to the Rietveld Quantitative Analysis (RQA) method. The data obtained showed that the raw red mud is composed by a mixture of seven different phases (hematite, goethite, sodalite, anatase, gibbsite, calcite, and amorphous). Finally in the interval of 1023–1523 K the following crystalline phases: hematite, nepheline, sodalite, anatase, perovskite, and pseudobrookite have been observed.