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11.
Marco?IottiEmail author ?yvind?Weiby?Gregersen St?rker?Moe Marianne?Lenes 《Journal of Polymers and the Environment》2011,19(1):137-145
The rheological behaviour of microfibrillar cellulose (MFC) water dispersions has been investigated. For the first time a
detailed study of shear dependent viscosity at low and high shear rate is presented. A peculiar time dependent behaviour measured
in the area between 0 and 1000 s−1 was identified. The study shows a hysteresis loop in the shear rate–viscosity relationship at low shear rate. Additional
time dependent shear rate measurements were performed, and a hypothesis for a mechanism of interaction and formation of a
fibrils network was suggested. Higher temperature caused lower viscosity values, and this difference was increased at higher
shear rate values. Oscillatory measurements showed how the closeness of the fibrils helps network creations. Data obtained
from high shear measurements showed that 1% MFC water dispersions had a dilatant behaviour at ultra high shear rates with
values increasing from 120 to 300 Pa s in the area between 180,000 and 330,000 s−1 . 相似文献
12.
K. N. Brooks H. M. Gregersen E. R. Berglund M. Tayaa 《Journal of the American Water Resources Association》1982,18(2):245-250
ABSTRACT: Deforestation and intensive land use on a global scale has resulted in watershed deterioration and threatened municipal and irrigation reservoirs. Watershed rehabilitation programs must allocate funds to priority projects. A tool for decisionmakers is presented which provides a four-step overview economic analysis by the integration of physical and biological considerations. The overview tool is applied to a current proposed watershed project in Morocco. 相似文献