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Gottshall Early Reading Intervention: A phonics based approach to enhance the achievement of low performing, rural, first grade boys.Gottshall, Dorothy Lee 12 1900 (has links)
Learning to read is critical for quality of life and success in our society. Children who cannot read well face unsuccessful educational careers and limited job choices. Recently, policy makers and educators have made progress toward increasing the reading achievement of America's children. Still up to 60% of boys who live in poverty cannot read or read two years below grade level. In this experimental study, I designed and examined the effects of the Gottshall Early Reading Intervention (GERI) to determine if direct instruction with a small group, phonics based approach would increase the literacy achievement of low performing, rural, first grade boys. Participants were selected according to Texas Primary Reading Inventory (TPRI) scores, matched them across race, ethnicity, and socio-economic status, and randomly assigned them to experimental/control group. Three times per week for 15 weeks, boys in the experimental group attended 30-minute pullout sessions taught by trained professionals in addition to classroom reading instruction. Control group members received classroom reading instruction only. Findings reveal no significant differences in reading gains across all variables. However, descriptive data indicate higher percentages of gains for the experimental group on four out of five reading components with rate of gain higher on fifth. Statistics also show that Hispanics are more likely to benefit.
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Desenvolvimento de blendas de poliestireno/composto de resíduo de borracha da indústria calçadista.SILVA, Divânia Ferreira da. 25 June 2018 (has links)
Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-06-25T20:43:17Z
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Previous issue date: 2018-06-25 / Capes / O objetivo deste trabalho foi desenvolver blendas de poliestireno/composto de
resíduo de borracha de estireno-co-butadieno (PS/SBRr) da indústria calçadista
visando tenacificar o PS e reaproveitar o SBRr. As blendas foram preparadas nas
composições (70/30; 60/40 e 50/50%) em massa e com 5% do compatibilizante
estireno-butadieno-estireno (SBS). A fim de se estudar o efeito da sequência de
mistura, escolheu-se a composição 50/50% que apresentou o melhor resultado de
resistência ao impacto. As sequências realizadas foram: PS/SBRr/SBS
47,5/47,5/5%; PS/SBRr + SBS 47,5/47,5 + 5% e PS/SBS + SBRr 47,5/5 + 47,5%
em massa. As blendas foram preparadas por extrusão seguida de injeção e
caracterizadas por reometria de torque, tração, impacto, flexão, temperatura de
deflexão térmica (HDT), análise térmica dinâmico-mecânica (DMTA), calorimetria
exploratória diferencial (DSC), microscopia eletrônica de varredura (MEV) e
microscopia eletrônica de transmissão (MET). Observou-se nos resultados dos
ensaios mecânicos redução no módulo de elasticidade e na resistência à tração e
um aumento significativo na resistência ao impacto quando comparados ao PS
para todas as composições. A HDT das misturas reduziu pouco em relação ao
PS. A sequência de mistura proporcionou bons resultados das propriedades
mecânicas, principalmente na composição PS/SBS + SBRr 47,5/5 + 47,5% em
massa. Por MEV e MET, pôde-se observar que as blendas compatibilizadas
obtiveram uma melhor distribuição das partículas de borracha com uma
morfologia mais estável que as não compatibilizadas. Estes resultados foram
confirmados por meio dos maiores valores de resistência ao impacto, o que indica
a ação do compatibilizante melhorando a adesão entre os componentes desta
blenda. Por DMTA constatou-se que estas blendas são imiscíveis. Portanto, fica
evidenciada a importância da reutilização dos resíduos de borracha tanto para a
tenacificação do PS como também para a redução dos problemas causados ao
meio ambiente, quando estes são descartados de forma indevida. / The aim of this study was to develop blends of polystyrene/compound of rubber
waste (PS/SBRr) of the shoes industry aiming to tough the PS and to reuse the
SBRr. The blends were prepared in the compositions (70/30; 60/40 and 50/50
wt.%) and with 5 wt.% of styrene-butadiene-styrene compatibilizer (SBS). In order
to study the effect of mixing sequence, the 50/50 wt.% composition, which
presented the best result in impact strength, was selected. The sequences were
PS/SBRr/SBS 47.5/47.5/5%; PS/SBRr + SBS 47.5/47.5 + 5% and PS/SBS + SBRr
47.5/5 + 47.5 wt.%. The blends were prepared by co-rotational twin screw extruder
and molded by injection and characterized by torque rheometer, mechanical
properties, heat deflection temperature (HDT), dynamic mechanical thermal
analysis (DMTA), differential scanning calorimetry (DSC), scanning electron
microscopy (SEM) and transmission electron microscopy (TEM). From the
mechanical tests, a reduction in elastic modulus and tensile strength and a
significant increase in impact strength were observed in relation to PS. The HDT
for all blends was reduced compared to the PS. The mixing sequence showed
good results in mechanical properties, especially in composition PS/SBS + SBRr
47.5/ 5 + 47.5 wt.%. By SEM and TEM it can be seen that the compatibilized
blends presented a better distribution of the rubber particles with a morphology
that was more stable than the one that was not compatibilized. These results were
confirmed by the highest impact strength values, indicating the compatibiliz er
action that improves adhesion among the components of the blend. By DMTA it
was possible to state that these blends are immiscible. Hence, the importance of
the reusing of rubber wastes is evidenced both for toughening of the PS and for
the reduction of problems caused to the environment, when they are discharged
improperly.
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