Search results for " Reflection"
showing 10 items of 345 documents
Modelling of light transmittance and reflectance in flat fluidized photoreactors
1992
In recent years several photon induced chemical reactions involving the use of a solid catalyst have been studied. Flat fluidized beds have proved to be promising devices for carrying out these photocatalytic reactions. There is therefore a need for the modelling of light interactions within such kinds of photoreactors. In this paper, a phenomenological model is proposed for simulating the light transmission and reflection in flat fluidized gas-solid photoreactors. A detailed description of the model is presented. The model predictions were compared with experimental data and a satisfactory agreement was found. Correlations were also suggested for the estimation of model parameters. Depuis …
Creating a bilingual pre-school classroom: the multilayered discourses of a bilingual teacher
2015
Teachers have an agentive role as they interpret, evaluate and develop language policies and practices. In the current study we interviewed a bilingual pre-school teacher in Finland during the first year of implementing a new way of working bilingually with a class of monolingual children. Applying nexus analysis, we explored the teacher discourses on the trajectory of the development of the new approach; the concepts, places and people that were circulating in her reflections; and how these connected with larger societal discourses. The analysis showed that the teacher's new bilingual language practices demanded the renegotiation of previously held personal and professional beliefs. The te…
Changing the ownership of ideas: Multimedial accomplishment of collaborative reflection in an organizational workshop
2022
Reflecting on work processes together with one's co-workers is becoming increasingly important in workplaces. This study examined collaborative reflection in the organizational context through analyzing a case of a complex workplace setting where an enterprise social media platform, talk-in-interaction, and handwriting were used to engage participants in the process of reflection. Drawing on the concept of remediation, the results show that collaborative reflection is interactionally accomplished through a multimedial activity chain, in which the ownership of presented ideas is transformed from individual ideas into shared views of the team. The study shows in detail how the process of coll…
Discovery-learning in grammar education:a study on anaphoric pronouns
2022
En les darreres dècades, en el context educatiu portuguès, com en altres països, la gramàtica ha estat un tema central de debat en l’educació L1. L’any 2001, amb la publicació del Currículum Nacional d’Educació Bàsica, la gramàtica, que es va anomenar «coneixement explícit de la llengua», es va considerar un dels components bàsics del currículum de L1 portuguès. Des d’aquesta perspectiva, inspirada en les propostes del moviment anglosaxó de consciència lingüística, l’objectiu principal de l’educació gramatical és desenvolupar els coneixements implícits que els infants ja tenen i utilitzen en un coneixement cada cop més reflexiu i explícit. En aquesta concepció, en què se suposa que «la majo…
On Complex Formation between 5-Fluorouracil and β-Cyclodextrin in Solution and in the Solid State: IR Markers and Detection of Short-Lived Complexes …
2020
In this work, the nuclear magnetic resonance (NMR) and IR spectroscopic markers of the complexation between 5-fluorouracil (5-FU) and &beta
Visualization of Keratin with Diffuse Reflectance and Autofluorescence Imaging and Nonlinear Optical Microscopy in a Rare Keratinopathic Ichthyosis.
2021
Keratins are one of the main fluorophores of the skin. Keratinization disorders can lead to alterations in the optical properties of the skin. We set out to investigate a rare form of keratinopathic ichthyosis caused by KRT1 mutation with two different optical imaging methods. We used a newly developed light emitting diode (LED) based device to analyze autofluorescence signal at 405 nm excitation and diffuse reflectance at 526 nm in vivo. Mean autofluorescence intensity of the hyperkeratotic palmar skin was markedly higher in comparison to the healthy control (162.35 vs. 51.14). To further assess the skin status, we examined samples from affected skin areas ex vivo by nonlinear optical micr…
Association of central and peripheral pulse pressure with intermediate cardiovascular phenoytpes
2012
Objective: We assessed the relationship between pulse pressure and intermediate cardiovascular phenotypes in a middle-aged cohort with high prevalence of hypertension. Background: It has been suggested that central pulse pressure (cPP) is a better predictor of cardiovascular outcome than peripheral pulse pressure (pPP), particularly in the elderly. Yet, it is unclear if cPP provides additional prognostic information to pPP in younger individuals. Methods: In 535 individuals we assessed cPP and pPP as well as the intermediate cardiovascular phenotypes pulse wave velocity (PWV; SphygmoCor, Complior, PulsePen), carotid intima-media thickness (C-IMT; carotid ultrasound), left-ventricular mass i…
L’inclusione vista dagli alunni: costruzione e validazione del questionario per rilevare la qualità inclusiva della scuola
2018
Molti studi nazionali e internazionali si sono concentrati sulla valutazione e sulla promozione della qualità inclusiva della scuola. Si tratta di un argomento complesso, che ha stimolato un ampio dibattito e una varietà di contributi che mettono in luce la necessità di uno strumento in grado di misurare la qualità inclusiva delle nostre scuole, per determinare l’evidenza empirica riguardo a questo tema. L’articolo presenta i risultati di una sperimentazione finalizzata alla redazione di un questionario per la rilevazione della qualità inclusiva del sistema scolastico percepita dagli alunni. Il questionario si pone come uno strumento di valutazione e autovalutazione che permette la misurazi…
Cu-substituted lanthanum ferrite perovskites: Preparation, characterization and photocatalytic activity in gas-solid regime under simulated solar lig…
2016
Lanthanum orthoferrites LaFeO3 nanopowders doped with 20 mol% of Sr and 0-10-20 mol% of Cu were prepared by citrate auto-combustion synthesis and investigated in terms of crystal structure, morphology, surface area and optical properties by using several characterization techniques. The band gap energy values were found to range from 2.35 eV for LaFeO3 to 1.86 eV for the samples with the highest content of copper, this trend reflects the decrease of the particle size. All powders showed photocurrent response, the highest photocurrent was obtained for undoped orthoferrite calcined at 600°C. Their physical-chemical properties were related to photoelectrochemical behaviour. The the position of…
Preliminary results on direct quantitative determination of cocaine in impregnated materials by infrared spectroscopy
2018
Abstract Partial least squares models were built for the direct determination of cocaine in seized impregnated smuggled materials. Measurements are based on the attenuated total reflectance middle infrared spectra (ATR-MIR) and diffuse reflectance spectra in the near range (DR-NIR) obtained directly from the surface of the impregnated materials. The aforementioned procedures offer fast, cheap and environmentally friendly green alternatives to the reference method based on the extraction of the drug and its quantification by gas chromatography. Additionally it has been verified that results found are statistically comparable with those obtained by the reference method with root mean square e…