Anaerobic digestion is a naturally occurring biological process in which large numbers of anaerobic bacteria convert organic matter into methane and carbon dioxide (a mixture called biogas) in the absence of air. It is a widely used biological process for treating wastewater solids. This process stabilizes the organic matter in wastewater solids, reduces pathogens and odors, and reduces the tot...

Understanding the nature of dense particle packings is a subject of intense research in the physical, mathematical, and biological sciences. The preponderance of previous work has focused on spherical particles and very little is known about dense polyhedral packings. We formulate the problem of generating dense packings of nonoverlapping, nontiling polyhedra within an adaptive fundamental cell...

The gravity sedimentation of three narrow-sized fractions of suspensions of magnetite particles exposed to magnetic fields ranging from 0 to 180 x 10 -4 T was studied experimentally. At volumetric solids concentrations in excess of 15%, the magnetized suspensions of magnetite with size fractions ranging from -75 to +38 μm settled more slowly than the non-magnetized suspensions. However, owing t...

regarding many disadvantages of traditional method to produce concentrated yoghurt, several attempts have been done for mechanization of process in industrial scale. using membrane systems especially ultra filtration is one of these methods. in this survey, method to produce direct concentrated yoghurt, fresh milk was concentrated to 19% snf by ultra filtration method then diluted to 13 and 16 ...

as a native fermented dairy drink, doogh is an important industrial product in iran. however, its characteristics have not been completely evaluated. this study evaluated the flow behavior, particle size distribution and stability of non-fat doogh as affected by the row material employed (fresh skim milk or skim milk powder) and the total solids (ts) content of the final drink. the viscosity of...

It is by now well established that loading conditions with suffi ciently large triaxialities can induce the suddenappearance of internal cavities within elastomeric (and other soft) solids. The occurrence of such a phenome-non, commonly referred to as cavitation, can be attributed to the growth of pre-existing defects into fi nite sizes.In the fi rst part of this discussion, I w...