Bioregenerative life support systems may be necessary for long-term space missions due to the high cost of lifting supplies and equipment into orbit. In this study, we investigated two biological wastewater treatment reactors designed to recover potable water for a spacefaring crew being tested at Johnson Space Center. The experiment (Lunar-Mars Life Support Test Project-Phase III) consisted of...

The vertical distribution of sulfate-reducing bacteria (SRB) in photosynthetic biofilms from the trickling filter of a sewage treatment plant was investigated with oligonucleotide probes binding to 16S rRNA. To demonstrate the effect of daylight and photosynthesis and thereby of increased oxygen penetration, we incubated two 4-mm-thick biofilm samples in darkness or exposed to light at natural ...

Cost estimation is an important consideration for the development and evaluation of wastewater treatment alternatives. This paper evaluates the most cost-effective treatment scheme among different plants employing two biological processes most commonly used for the treatment of municipal wastewater in Saudi Arabia, activated sludge and trickling filtration, by using a computer-based treatment c...

‎in this paper‎, ‎the notion of the radical of a filter in‎ ‎residuated lattices is defined and several characterizations of‎ ‎the radical of a filter are given‎. ‎we show that if f is a‎ ‎positive implicative filter (or obstinate filter)‎, ‎then‎ ‎rad(f)=f‎. ‎we proved the extension theorem for radical of filters in residuated lattices‎. ‎also‎, ‎we study the radical‎ ‎of filters in linearly o...

This paper presents a method for the determination of alkylphenols, alkylphenol polyethoxylates (APEO) and alkylphenol ethoxycarboxylates (APEC) in the aqueous and particulate phase of wastewater samples. Quantification was achieved by liquid chromatography-tandem mass spectrometry. The sensitivity of the method is demonstrated by low detection limits, in the dissolved phase 1.2-9.6ngl(-1) for ...

in this paper, we proposed a novel structure for designing all optical filter based on photonic crystal structure. in designing the proposed filter, we simply employed a point defect localized between input and output waveguides as wavelength selecting part of the filter. the initial form of this filter is capable of selecting optical waves at =1560 nm, the transmission efficiency of the filte...

Microbial mass can be said to occur in one of two states; as 'flocs' frcely suspended in an aqueous medium, or as a 'film' adhering to a support surface. Industrial fermenter configurations, at least since the development of deep-tank fermentation, have almost invariably been based on the use of microbial flocs, and the occurrence of a visible microbial film during fermentation is generally avo...