Research suggests that the literature around teachers’ technology experiences, variously lack currency, breadth, consistency, and depth. The purpose of this qualitative descriptive study was to ...explore how teachers describe their experiences using technology in a BYOD classroom at a small Catholic School in Maryland. The participants consisted of a sample size of 18 conveniently selected teachers. Puentedura’s 2006 substitution, augmentation, modification, and redefinition (SAMR) model was leveraged as a primary theoretical framework to guide this study as well as form the basis for its research questions.The research question was how teachers describe their experiences using technology in a BYOD classroom. One-on-one interviews and focus groups were conducted to answer the study’s research questions. The results of the study suggested that the teachers had mixed emotions and experiences around technology depending on various factors such as the type of technology, the subject matter being taught, or the aspect of technology being referred to. For example, more than 40% of the teachers suggested that ease of use was a factor in their acceptance of technology, while others categorically denied the benefits of technology for their classroom. Implications of the study and recommendations for future research are discussed.
The key to the general and efficient palladium‐catalyzed formylation of aryl and heteroaryl bromides is the use of the di‐1‐adamantyl‐n‐butylphosphane (cataCXium A) as ligand. Low pressure of the ...synthesis gas and appropriate choice of the base are also important for high yields (up to 99 %) of a broad range of (hetero)aromatic aldehydes at unprecedented low catalyst concentrations (see scheme; TMEDA= N,N,N′,N′‐tetramethylethylenediamine).
The Energetic Particle Detector Rodríguez-Pacheco, J; Wimmer-Schweingruber, R F; Mason, G M ...
Astronomy & astrophysics,
10/2020, Letnik:
642
Journal Article
Recenzirano
Odprti dostop
After decades of observations of solar energetic particles from space-based observatories, relevant questions on particle injection, transport, and acceleration remain open. To address these ...scientific topics, accurate measurements of the particle properties in the inner heliosphere are needed. In this paper we describe the Energetic Particle Detector (EPD), an instrument suite that is part of the scientific payload aboard the Solar Orbiter mission. Solar Orbiter will approach the Sun as close as 0.28 au and will provide extra-ecliptic measurements beyond ∼30° heliographic latitude during the later stages of the mission. The EPD will measure electrons, protons, and heavy ions with high temporal resolution over a wide energy range, from suprathermal energies up to several hundreds of megaelectronvolts/nucleons. For this purpose, EPD is composed of four units: the SupraThermal Electrons and Protons (STEP), the Electron Proton Telescope (EPT), the Suprathermal Ion Spectrograph (SIS), and the High-Energy Telescope (HET) plus the Instrument Control Unit that serves as power and data interface with the spacecraft. The low-energy population of electrons and ions will be covered by STEP and EPT, while the high-energy range will be measured by HET. Elemental and isotopic ion composition measurements will be performed by SIS and HET, allowing full particle identification from a few kiloelectronvolts up to several hundreds of megaelectronvolts/nucleons. Angular information will be provided by the separate look directions from different sensor heads, on the ecliptic plane along the Parker spiral magnetic field both forward and backwards, and out of the ecliptic plane observing both northern and southern hemispheres. The unparalleled observations of EPD will provide key insights into long-open and crucial questions about the processes that govern energetic particles in the inner heliosphere.
Article aims to highlight the current status of youth in contemporary Spanish narrative of travel and adventure, and its value in the reader training secondary students. Literary analysis of these ...novels and narrative history of this subgenre, and the establishment of a literary canon to date we provide the basis to define a poetics of adventure novels.
The synthesis of a novel class of atropisomer chiral diphosphine ligands with a bornene framework is described. The new ligands showed in Rh catalyzed asymmetric hydrogenation of α- and β-enamides ...very high ee’s (more than 99%).
The synthesis of a novel class of atropisomer chiral diphosphine ligands with a bornene framework is described. The new ligands showed in Rh catalyzed asymmetric hydrogenation of α- and β-enamides very high ee’s (more than 99%).
C
2-Symmetrical ferrocenyl diamino diphosphines (diamino FERRIPHOS ligands) proved to be excellent ligands for the rhodium-catalyzed enantioselective reduction of methyl α-acetamidoacrylates. The ...straightforward synthesis, their air stability and the easy modification of their structure makes these ligands especially interesting for transition metal-catalyzed hydrogenations. α-Amino acids with enantioselectivities greater than 95% (and up to 99.3%
ee) were obtained with no need of further recrystallization.
The new – commercially in multi‐kg quantities available – chiral bisphospholane ligand, catASium® M, has been successfully used in the Rh(I)‐catalysed enantioselective hydrogenation of itaconic acid ...derivatives. Chiral ß‐substituted succinic acid derivatives were produced in good to excellent enantioselectivities. Turnover frequencies by up to 40,000 h−1 have been achieved.
The reductive lithiation of various α‐ferrocenylcarbinol derivatives yields stable α‐ferrocenyllithium species (see scheme). These can be quenched with different electrophiles with complete retention ...of configuration.
A direct stereoselective substitution of α-aminoalkylferrocenes of type
3 with organozinc reagents provides chiral ferrocenes which can be converted to the FERRIPHOS ligands of type
1 in a one-pot ...procedure. These FERRIPHOS ligands have been used for the Rh-catalyzed asymmetric hydrogenation of an enol acetate with 94.9%
ee.
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