Etude de la circulation dans les bassins d'aeration a boues activeesStudy of the circulation pattern in aeration tanks

Keeping the mixed liquor in suspension is one of the critical problems in aeration tanks. This can only be assured by adequate circulation of the liquid. A hydrodynamic study in different laboratory and industrial scale aeration tanks, has been carried out to characterise the circulation (bottom velocity, V_f, mean circulation velocity) using the following parameters i.e. tank geometry and air flow rate G. This study also proposes a scale-up criterion for aeration tanks. All the dimensions of these tanks are given in Table 1.     

Learning through international acquisitions: The process of knowledge acquisition in China

Abstract and Key Results

The role of carbon pricing in the relationship between air freight and environmental resource depletion: a case study of Saudi Arabia

Clean Technologies and Environmental Policy - The relationship between air freight and environmental resource depletion is a widely explored area in different economic settings. There, however, is...     

Differentiation in human amniotic fluid cell cultures: I: Collagen production

Plasma from a patient factor VIII inhibitor was mixed at several low concentrations with fresh normal plasma. The factor VIII deficient plasmas obtained after a short incubation period were used as substrate plasmas in the normal one-stage factor VIII assay method. Results obtained using 0.5-1% of the inhibitor plasma in normal plasma compared favourably with those obtained using normal haemophilia A factor VIII deficient plasma provided that tests were carried out without delay. A single plasma exchange of this patient provided enough antibody to prepare more than 500 litres of factor VIII deficient plasma by simple mixing with fresh normal plasma.     

Hydrogen Balmer-β and Balmer-γ emission profiles in an abnormal glow region of hydrogen plasma

Emission spectroscopy measurements of Balmer-β and Balmer-γ line profiles are carried out to study their line shapes and line intensities as a function of discharge parameters such as fill pressure (3-7 mbar) and input power (200-400 W). A technique based on determining the relative intensities of neutral atomic hydrogen emission lines is used to evaluate the electron temperature, whereas the electron density is extracted from the Stark broadening (FWHM) of the H_β emission profile. It is found that both the emission intensity and the broadening of the Balmer-β and Balmer-γ lines exhibit significant dependence on the fill pressure in the same manner. However, both the emission intensity and broadening of the H_β line exhibit a weak dependence on input power in contrast to the H_γ emission line. Based on optical measurements reported here, plasma discharge parameters can be selected to optimize the electron temperature and density.