JUNE 2008 B ioreactor technologies for mammalian cell culture may seem quite sophisticated (1). In fact, efficient mammalian cell culture is simple and requires just two major elements: mixing and oxygen (O2) transfer. Traditional methods for mixing use an impellor, and the classical O2 transfer method features a sparging stone that expels air bubbles to increase the O2 transfer surface area in...

Water circulation in storage tanks significantly impacts water quality distribution networks since old tends to have low residual chlorine concentrations that are insufficient neutralize microbial regeneration. Their large capacity and long residence times result uneven mixing, which can accelerate the disinfectant decay formation of potentially carcinogenic disinfection by-products. The phenom...

Turbulence is one of the ubiquitous aspects aquatic systems and affects many physical biological processes. Based on direct velocity measurements a computational fluid dynamics (CFD) simulation, we characterized distribution turbulent kinetic dissipations rates (?) in an orbital shaker system within range rotation frequencies. CFD was able to estimate ? containers accurately, which confirmed by...

Abstract The effects of 17α-methyltestosterone administration on spermatophore quality in captive broodstock tiger shrimp Penaeus monodon were investigated using injection method and oral based the optimized protocol. experiment was designed to compare group with two replications during a 38-day experimental period. Captive male weighing 57-95 g collected from ponds stored 10,000 m 3 concrete t...

W ithin this thesis, the Computational Fluid Dynamics method Smoothed Particle Hydrodynamics (SPH) is applied to simulate bubble induced mixing in wastewater treatment plants for the first time. To do so, a new SPH multiphase algorithm is presented that is especially designed to be very cheap in terms of computational costs and solves the problem that air bubbles are only stable for a short tim...

Background The objective of the present study was to evaluate the growth performance and feed utilization of African catfish Clarias gariepinus fed a commercial diet and reared in the biofloc system enhanced with probiotic. Methods The treatment was the frequency of probiotic application into the cultured system, namely, 5-day interval, 10-day interval, and 15-day interval for 60 days of experi...

Background The objective of the present study was to evaluate the growth performance and feed utilization of African catfish fed a commercial diet and Clarias gariepinus reared in the biofloc system enhanced with probiotic. Methods The treatment was the frequency of probiotic application into the cultured system, namely, 5-day interval, 10-day interval, and 15-day interval for 60 days of experi...

Industrial wastewater contains a lot of pollutants and therefore needs special treatment processes. The treatment process may contain mechanical, biological, chemical, physical and physiochemical such as Coagulation – Flocculation process. The goal of this experimental work was to investigate the effects of coagulationflocculation and dissolved air flotation as a hybrid process of industrial wa...

Risers are considered vital parts on fluidized catalytic cracking (FCC) conversion units. It is inside the riser that the heavy hydrocarbon molecules are cracked into petroleum fractions such as gasoline and liquefied petroleum gas (LPG). A simplified kinetic flow model in combination with the Tank-In-Series model was used to predict the conversion response of an FCC riser to changes in feed te...

The performance metric for tank cars and other hazardous materials vehicles involved in accidents has generally been conditional probability of release given involvement in an accident. This metric considers the probability of a release event occurring but does not take into account the quantity of product lost in a release incident. In this paper, a new metric termed “release risk” is introduc...