22 resultados para Subnormal agglomerate


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In this work, air dielectric barrier discharge (DBD) operating at two different frequencies (60 Hz and 17 kHz) was used to improve surface properties of polypropylene (PP). The changes in surface hydrophilicity were investigated by contact angle measurements. The modifications in chemical composition of PP surface were studied by X-ray photoelectron spectroscopy (XPS) and Fourier-transformed infrared spectroscopy (FTIR). The PP roughness were analyzed before and after the DBD treatment using atomic force microscopy (AFM). In order to compare the results obtained at different frequencies, the analyses are presented as a function of the deposited energy density. The results show that both DBD treatments led to formation of low-molecular weight oxidized material (LMWOM). It tends to agglomerate into small mounts on the surface, as shown by AFM analyses. These structures are weakly bounded to the surface and can be easily removed by rinsing in polar solvents. After washing the DBD-treated samples, the PP partially recovers its original wetting characteristics. This suggests that oxidation also occurred at deeper and more permanent levels on the PP samples. Comparing both DBD treatments, the 17 kHz process was found to be more efficient in introducing oxygen groups to the PP surface

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This work is situated in the universe of resource rooms with a focus on the teachinglearning disabled students with low vision and visual in two cities of São Paulo. The paper discusses theoretically the historical emergence of these rooms, the deployment in the State of São Paulo and its importance within the context of school inclusion of students with visual impairments. Its purpose is to conduct a general survey of the operating conditions of the rooms from the perspective of the teacher of students. The results verified the contribution of this service as a complementary tool of the ordinary classroom, the use of specific instructional materials and overall educational performance of students. The results indicate that this type of specialized care while receiving criticism, does not promote segregation, but what about the educational needs of these students, who despite the lack of vision, school performance is equal to or better than the other students in the classroom common, it all depends on family support, and dedication to studies by the student. Research has shown students satisfied with the services provided in the resource room, as well as integration and good relationships between teachers and students. We could also highlight the importance of specific training and mastery of knowledge by the teacher to work with the visually impaired person. At the end the results were sent to the schools of this research object of study so that it can contribute to effective work in the educational process for visually impaired students in resource rooms

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)