9 research outputs found
Upstream structural management measures for an urban area flooding in Turkey
In recent years, flooding has become an increasing concern across many parts
of the world of both the general public and their governments. The climate
change inducing more intense rainfall events occurring in short period of
time lead flooding in rural and urban areas. In this study the flood
modelling in an urbanized area, namely Samsun-Terme in Blacksea region of
Turkey is performed. MIKE21 with flexible grid is used in 2-dimensional
shallow water flow modelling. 1 × 1000−1 scaled maps with the buildings for the
urbanized area and 1 × 5000−1 scaled maps for the rural parts are used to obtain
DTM needed in the flood modelling. The bathymetry of the river is obtained
from additional surveys. The main river passing through the urbanized area
has a capacity of 500 m3 s−1 according to the design discharge obtained
by simple ungauged discharge estimation depending on catchment area only.
The upstream structural base precautions against flooding are modelled. The
effect of four main upstream catchments on the flooding in the downstream
urban area are modelled as different scenarios. It is observed that if the
flow from the upstream catchments can be retarded through a detention pond
constructed in one of the upstream catchments, estimated Q100 flood can
be conveyed by the river without overtopping from the river channel. The
operation of the upstream detention ponds and the scenarios to convey
Q500 without causing flooding are also presented. Structural management
measures to address changes in flood characteristics in water management
planning are discussed
Lipolytic enzymes and hydrolytic rancidity
Lipolysis, the enzymic hydrolysis of milk lipids to free fatty acids and partial glycerides, is a constant concern to the dairy industry because of the detrimental effcts it can have on the flvor and other properties of milk and milk products. However, free fatty acids also contribute to the desirable flavor of milk and milk products when present at low concentrations and, in some cheeses, when present at high concentrations. The enzymes responsible for the detrimental effects of lipolysis are of two main types: those indigenous to milk, and those of microbial origin. The major indigenous milk enzyme is lipoprotein lipase. It is active on the fat in natural milk fat globules only after their disruption by physical treatments or if certain blood serum lipoproteins are present. The major microbial lipases are produced by psychrotrophic bacteria. Many of these enzymes are heat stable and are particularly significant in stored products. Human milk differs from cows' milk in that it contains two lipases, a lipoprotein lipase and a bile salt-stimulated lipase. The ability of the latter to cause considerable hydrolysis of ingested milk lipids has important nutritional implications