992 resultados para medidas flexibilidad interna


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A site investigation program was carried out to detect salt-water intrusions in a shallow sedimentary aquifer based on electrical resistivity measurements. The site is located close to Paranaguá harbor, in the Paraná State, Brasil. At this site, high chloride concentration contaminated shallow water wells used to supply water for local industries. The site investigation program included a fieldwork, dipole-dipole electrical profiling, resistivity piezocone tests, physical-chemical analysis of sampled water and interpretation of borehole logs. The resistivity piezocone tests provided two simultaneous information; the soil stratigraphy at a very detailed level and a quasi-continuous resistivity profile. Both information adequately complemented dipole-dipole electrical profiling test data. The integration of all test data allowed identifying the contaminated areas as well as guided the location of new water wells to be installed in this area.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Nitrofurazone (NF), 5-nitro-2-furaldehyde semicarbazone, a broad-spectrum antibiotic, has reported toxic effects and low solubility in water. It would be of great interest to form inclusion complexes between NF and a cyclodextrin, to develop more effective and safer antibiotic formulations. This paper focuses on the preparation of inclusion complexes of NF with 2-hydroxypropyl-β- cyclodextrin (HP-β-CD) and their initial characterization by evaluating rates of complex formation, photostability, solubility isotherms, release rate profiles, stoichiometry of the complexes and their morphology, as revealed by scanning electron microscopy. The kinetic tests of complex formation revealed that 17,3 h is enough for stabilization of the NF-cyclodextrin complex. The solubility isotherm studies showed that the isotherm changes from type A to type B, as a function of temperature. The photostability experiments showed that the insertion of the NF in the HP-β-CD cavity protects the drug from photodecomposition. The release kinetic tests showed that the profile of NF release from the complex is altered by the presence of HP-β-CD in the medium. A Job's plot indicated that the stoichiometry of the complex was 1:1 NF:HP-β-CD. The scanning electron micrographs showed changes in the crystal structure of NF in the complex. This study focused on the physicochemical properties of drug-delivery formulations that could potentially be developed into a novel type of therapy with NF.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aim of this investigation was to evaluate four reference methods to estimate evapotranspiration (Makkink, Hargreaves, Class A pan and Radiation), compared tb Penman-Monteith method, that is considered standard by the Food and Agricultural Organization of the United Nations (FAO). Errors due to variable measurements in the reference evapotranspiration estimate were taken into consideration. The research was developed in an experimental area of the Department of Rural Engieering of the School of Agricultural and Veterinarian Sciences, Campus of Jaboticabal, São Paulo State University. An automated weather station was used and it was equipped with sensors to measure global and net radiation, temperature, relative humidity, and wind speed. The aftermath showed a better adjustment to Hargreaves. Makkink, Class A pan and Radiation methods are different from Penman-Monteith, therefore, they cannot be compared. To evaluate methods to estimate evapotranspiration and avoid possible evaluation errors, ETo estimate errors must be considered.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Incluye Bibliografía

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Incluye Bibliografía

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Incluye Bibliografía

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Incluye Bibliografía

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Incluye Bibliografía

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Incluye Bibliografía