today, environmental crisis and loss of natural resources are the principle causes of the creation of environmental management systems. the optimal management of natural resources requires the assessment and classification of ecological and environmental potentials. using this method, the abilities and restrictions of resources can be recognized, and their future trends can be predicted. nebka ...

Today, environmental crisis and loss of natural resources are the principle causes of the creation of environmental management systems. The optimal management of natural resources requires the assessment and classification of ecological and environmental potentials. Using this method, the abilities and restrictions of resources can be recognized, and their future trends can be predicted. Nebka ...

Thermostable chitinases are useful for industrial and biotechnological applications. This paper reports the stabilization of chitinase from Serratia marcescens B4A through rational mutagenesis. Changing of Ser 390 to Ile in S. marcescens. The stabilization was enhanced through entropic stabilization by reduction of the loop length and also by increasing of the beta chain length. With this repla...

to construct copper heap leaching structures, a stepped heap of ore is placed over an isolated sloping surface and then washed with sulphuric acid. the isolated bed of such a heap consists of some natural and geosynthetic layers. shear strength parameters between these layers are low, so they form the possible sliding surfaces of the heaps. economic and environmental considerations call for stu...