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Reflecting on reflection: scale extension and a comparison of undergraduate business students in the United States and the United Kingdom
In the Peltier, Hay, and Drago (2005) article entitled “The Reflective Learning Continuum: Reflecting on Reflection,” a reflective learning continuum was conceptualized and tested. This is a follow-up article based on three extensions: (1) determine whether the continuum could be expanded, (2) further validating the continuum using additional schools, and (3) determining whether the continuum could also be applied to undergraduate business education. The findings from a study of U.S. and UK students show that the revised scale is valid and reliable and that U.S. students in the sample universities rated their educational experience higher and were more likely to use reflective thinking practices
Study-development of improved photointerpretative techniques to wheat identification
There are no author-identified significant results in this report
Carbonate sedimentation through the late Precambrian and Phanerozoic
The global sediment mass-age distribution indicates large variations in the rates
of carbonate sedimentation through time. The largest mass of carbonate deposited during
the entire history of the earth was produced during the Cambrian, possibly following on an
episode of phosphogenesis in the Late Precambrian. A second major episode occurred during the Late Devonian, probably reflecting the invasion of land by plants that altered the
rock-weathering and soil-forming regimes. Other lesser pulses of carbonate deposition occurred
in the Late Permian, Triassic, and Cretaceous. A shift in the locus of carbonate deposition
from shallow waters to the deep sea occurred during the Cretaceous
Understanding and modeling the sedimentary system
The sedimentary system involves
processes that weather rocks and reduce
them to soluble and fine-grained
particulate components that can be
transported. deposited, and transformed
back into rock. !Jost of the processes can
be observed today, but the present is an
unusual episode in our planet's history.
We live in a brief warm interglacial epi sode
in an interval usually characterized
by large mid-and high-latitude icc sheets
and a much lower sea level. To complicate
matters further, few measurements
of process rates were made before the significant
impacts of agriculture and the
industrial revolution altered them. Consequently,
the rates at which different
processes operate over most of geologic
time arc not well known. The objective of
modeling sedimentary systems is to simplify
these processes so that they can be
described in mathematical terms. Successful
models predict the results of weathering.
erosion, transport, depositional
and diagenetic processes and allow us to
determine process rates from ancient deposits.
Modeling can also suggest the
kinds of geologic information that can be
used for its validation
Sedimentological and geochemical trends resulting from the breakup of Pangaea
The breakup of Pangaea and formation of the Atlantic and Indian Oceans and the marginal seas has an important influence on the global geochemistry of sediments
Letter from W. H. Hay
Letter in response of a position in the military department at Utah Agricultural College
The Catalysed Decarboxylation of Oxaloacetic Acid
The nature of the chelate compounds formed by transition metal ions with oxaloacetic acid in aqueous solution, has been investigated spectrophotometrically and potentiometrically. The mechanism of the catalysed reaction has been clarified. Thermodynamic information on the ketonic chelate compounds, which are the catalytically active species in decarboxylation, has been obtained by measuring association constants for dimethyloxaloacetic acid (II) (which cannot enolise),and comparing these with the known association constants for oxaloacetic acid (I), HO2C.CO.CH2.CO2H (I); HO2C.CO.C(Me)2.CO2H (II). Spectrophotometric studies have demonstrated the presence of enolic chelate compounds which are not decarboxylated. Approximate values for the proportion of enolic complex for oxaloacetate chelates of Ca2+, Mn2+, Zn2+, Co2+, Ni2+ and Cu2+ have been obtained. Spectrophotometrie measurements on the chelate compounds of oxaloacetic acid (I) and its ethyl ester (III), HO2C.CO.CH2.CO2Et (III) which cannot decarboxylate, have shown that oxaloacetate chelate compounds are formed very rapidly. The rise of optical density (270 mmu) with time to a maximum; produced by addition of some metal ions to aqueous solutions of oxaloacetic acid, is due to the production of an enolic pyruvate intermediate. The mechanism of decarboxylation, may be represented by, (diagram redacted) The changes of optical density with time are consistent with the above reaction scheme. Inhibition of decarboxylation at high copper ion concentrations has been found to occur, and the results are related to previous potentiometric studies of the copper chelates. Inhibition at high pH (> 6) is due to the production of kinetically inactive enolic complexes. The aniline catalysed decarboxylation of oxaloacetic acid has been studied by manometric, spectrophotometric, and potentiometric methods. Experiments with the half ester of oxaloacetic acid (III),have shown that in aqueous solution, the intermediate is the ketimine hydrate (A). Kinetic measurements have demonstrated that the rate of the aniline catalysed decarboxylation passes through a maximum at around pH 4. The pH-Rate profile is consistent with a catalytically active species (B), the fall in rate at pH greater than being attributed to ionisation according to the equation (equation redacted) Kinetic measurements have shown that the ketimine hydrate is present only in small amounts, under the experimental conditions used, and that it loses CO2 in the rate-determining step. In aqueous solution the mechanism is of the type, (diagram redacted) In ethanol, experiments with esters (III) and (IV) EtO2C.CO.CH2.CO2Et (IV) have shown that the catalytically active species is the ketimine (C). This compound is formed in quantitative yield. The aniline salt of compound (a), and the diethyl ester derivative of (C) have been isolated. The formation of the ketimine has been studied spectrophotometrically and shown to be kinetically second order. The rate of formation of the ketimine is equal to the rate of decarboxylation, indicating that in ethanol, the formation of the ketimine is the rate-controlling step in decarboxylation. Metal ion and amine catalysis have been compared with the metal ion activated enzymatic decarboxylation of some biologically important keto acids
Charge identification for spectral lines in nitrogen
Ion charge identification for spectral lines in nitrogen by beam foil light source techniqu
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