2,217 research outputs found
A Case study to Examine Student Retention at a Less Selective University with a High Rate of Retention
This case study sheds light on successful matriculation practices which emerge from the combination of institutional efforts and student needs. In order to discern successful matriculation data was collected in the form of interviews, observations, and documents at a less selective college with a high rate of retention. Mortimer Adler College possesses unique qualities with respect to curriculum, student population, teaching styles, and student life which affect retention in both positive and negative ways. The institution utilizes a highly structured Great Books curriculum and does not utilize traditional grading and assessment methods. The methods of student socialization are also explored through interviews with faculty and administrators. The findings of this study reveal the qualities of Mortimer Adler College which both support and hinder student success. The study also gives insight to the views of students within this unique institutional setting, focusing on their needs and goals and how their perceptions of the institution impact retention. The review of practices at this institution combined with the perception of the student body allows for the examination of programs and practices employed by Mortimer Adler College which aid in improving and supporting high retention that may also be used at other institutions of higher education.
Higher Education, Retention, Persistence, Great Books, Socialization, Faculty Student Relationship
Probing protoneutron star density profile from neutrino signals
Supernovae of Type II is a phenomenon that occurs at the end of evolution of
massive stars when the iron core of the star exceeds a mass limit. After
collapse of the core under gravity the shock wave alone does not succeed in
expelling the mass of the star and in this sense the role of neutrinos is the
most important mechanism to do so. During the emission of neutrinos flavor
conversion is possible, related the phenomenon of oscillations, which however
depends directly on the particular density profile of the medium. In this paper
we present results of numerical simulations of neutrino flavor conversion in
protoneutron stars and after collapse. The probabilities of survival for a
given flavor in a complete three-flavors framework is estimated through an
algorithm which conserves unitarity to a high degree of accuracy. The
sensitivity of the results to the different adopted models for the protoneutron
star structure is examined in detail demonstrating how the neutrino signal
could be used to check the validity of models.Comment: 9 figure
Sequential biological and photocatalysis based treatments for shipboard slop purification: A pilot plant investigation
This study investigated the treatment of a shipboard slop containing commercial gasoline in a pilot plant scale consisting of a membrane biological reactor (MBR) and photocatalytic reactor (PCR) acting in series. The MBR contributed for approximately 70% to the overall slop purification. More precisely, the biological process was able to remove approximately 40%, on average, of the organic pollution in the slop. Nevertheless, the membrane was capable to retain a large amount of organic molecules within the system, amounting for a further 30% of the influent total organic content removal. However, this affected the membrane fouling, thus resulting in the increase of the pore blocking mechanism that accounted for approximately 20% to the total resistance to filtration (2.85∙10 13 m −1 ), even if a significant restoration of the original membrane permeability was obtained after chemical cleanings. On the other hand, the biological treatment produced a clear solution for the photocatalytic system, thereby optimizing the light penetration and generation of highly oxidizing active oxygen species that enabled the degradation of bio-recalcitrant compounds. Indeed, low total organic carbon (TOC) values (<10 mg L −1 ) were achieved in the output of the photocatalytic reactor by means of only 60 Einstein (E) of cumulative impinging energy after the addition of K 2 S 2 O 8 . Overall, coupling the two processes enabled very high TOC removal (ca. 95%)
Overview on oxidation mechanisms of organic compounds by TiO2 in heterogeneous photocatalysis
This review provides the reader with a general overview on heterogeneous photocatalytic oxidation
mechanisms in the presence of TiO2, with a special address to conversion of aliphatic and aromatic organic
species. The aim was to clarify the steps of the photo-oxidation of the various classes of compounds and to
relate them with the properties of the catalysts and the experimental conditions used. Reactions carried
out to perform complete degradation and photocatalytic partial oxidations have been deeply discussed.
Recent isotopic studies highlighted new reaction pathways concerning partial oxidation of alcohols to
aldehyde and oxidation of benzene while EPR investigations confirmed that not only the photogenerated
hole but also the OH radicals are involved in the oxidation of the substrates
Visible Light Induced Oxidation of Trans-ferulic Acid by TiO2 Photocatalysis
The oxidation of trans-ferulic acid (C 10H 10O 4) in aqueous TiO 2 dispersion occurs via the formation of a charge-transfer complex on the TiO 2 surface that is able to absorb visible light (\u3bb 65 400 nm). The main product is CO 2, whereas secondary oxidation products are organic species such as vanillin, caffeic acid, homovanillic acid, and vanillylmandelic acid. Oxidation through the formation of a charge-transfer complex occurs only in the presence of specific TiO 2 samples. Experiments in the absence of oxygen, in the presence of bromate ions and by using a phosphate-modified TiO 2, have been carried out for investigating the reaction mechanism. In order to study the interaction between trans-ferulic acid and TiO 2 surface and to characterize the charge-transfer complex, UV-Vis diffuse reflectance and FT-IR spectroscopies have been used. FT-IR characterization of TiO 2 samples in contact with the aqueous trans-ferulic acid solution indicates that the charge-transfer complex formation occurs via adsorption of bidentate ferulate species
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