PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 16161274

[C2H4 reducing facility for controlled ecological life support system].

Wei-dang Ai·Shuang-sheng Guo·Xiang-yang Liu·Wen-hua Leng
View original source ↗Export metadata ↓

Abstract

OBJECTIVE: To develop an experimental facility for reducing C2H4 produced by plants' growing in the controlled ecological life support system (CELSS). METHOD: Based on technical parameters and performance requirements, project planning, design drawing, fabrication, and debug were conducted. Then, an experimental test for reducing C2H4 was done by measuring the content of C2H4 in gases between the inlet and the outlet of the facility. Its C2H4 decomposing capacity was evaluated. RESULT: The facility worked well, and the parameters, such as energy consumption, and volume, met the design requirements. The experimental test results demonstrated that the content of C2H4 was reduced from 0.034 mg/kg to below 0.010 mg/kg, under the condition that the relative humidity and velocity of flow of the inlet-gas was 20% and 1.0-3.0 L/min respectively, and power of the lamp was 48 W. Considering the composition and the content of the gas in the outlet of the facility, there was no harmful product to the plants, except CO2 and H2O. CONCLUSION: The facility has reasonable technical indices, and smooth and dependable performances. It can be used as a facility for decomposing C2H4 in plants growing system in CELSS.

Explore related subjects

Air ConditioningAir PollutantsAir Pollution, IndoorCatalysisEcological Systems, ClosedEthylenesEvaluation Studies as TopicHumidityLife Support SystemsPhotochemistryPlant DevelopmentPlant Growth RegulatorsPlantsEnglish AbstractJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Wei-dang Ai, Shuang-sheng Guo, Xiang-yang Liu, Wen-hua Leng. 2005. [C2H4 reducing facility for controlled ecological life support system].. https://pubmed.ncbi.nlm.nih.gov/16161274/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

Monitoring of biofilm-associated Legionella pneumophila on different substrata in model cooling tower system.

Cooling towers have the potential to develop infectious concentrations of Legionella pneumophila. Legionella counts increases where biofilm and warm water temperatures are present. In this study, biofilm associated L. pneumophila and heterotrophic bacteria were compared in terms of material dependence. Model cooling tower system was experimentally infected by L. pneumophila standard strain and monthly monitored. Different materials were tested for a period of 180 days. The lowest L. pneumophila and heterotrophic plate counts were measured on plastic polymers, whereas L. pneumophila and heterotrophic bacteria were accumulated rapidly on galvanized steel surfaces. It can be concluded that selection of plastic polymers, as a manufacturing material, are suitable for recirculating water systems.

Air Conditioning↗
PubMed2007

Real-time evaluation of ventilation filter-bank systems.

This study evaluated two government facility ventilation systems. One was a metropolitan government office complex with a recirculation system where outside air was the makeup air; the other was a NIOSH facility that used 100% outside air with no recirculation. The methodology employed was a modified American Society of Agricultural Engineers standard (S525) for testing total enclosure filtration efficiency, in agricultural tractor cabs, with optical particle counters (OPC). The low-efficiency bag filters were tested when new and after being in the ventilation system for 3 months. The replacement medium-efficiency filters were evaluated for 6 months (the manufacturer's suggested change-out schedule). These eight-chamber, medium-efficiency filters had an increased filter surface area that resulted in increased airflow through the system. Unfortunately, these filters contained electrostatic filter media and lost filtration efficiency rapidly, which was subsequently confirmed in a 30-day study conducted to determine an appropriate change-out schedule for the eight-chamber bag filters. The study determined that less than 6 months' use was justified due to the reduced efficiency of the electrostatic filter media. The NIOSH facility's air handler #8 (100% outside air unit) was upgraded from electrostatic bag filters, which had a suggested 9-month change-out schedule, to V Bank mechanical, wet-laid, glass fiber filters. The results of a 3-year evaluation showed that the V Bank filters had better filter efficiency after 3 years of service than the electrostatic filters had at 9 months. Both studies employed matched OPC instruments to reduce instrument-to-instrument bias. The methodology is adaptable to monitoring the total efficiency of most air filtration systems, and results can help make decisions about upgrading filter performance.

Air Conditioning↗
PubMed2006

Integrated real-time PCR for detection and monitoring of Legionella pneumophila in water systems.

We evaluated a ready-to-use real-time quantitative Legionella pneumophila PCR assay system by testing 136 hot-water-system samples collected from 55 sites as well as 49 cooling tower samples collected from 20 different sites, in parallel with the standard culture method. The PCR assay was reproducible and suitable for routine quantification of L. pneumophila. An acceptable correlation between PCR and culture results was obtained for sanitary hot-water samples but not for cooling tower samples. We also monitored the same L. pneumophila-contaminated cooling tower for 13 months by analyzing 104 serial samples. The culture and PCR results were extremely variable over time, but the curves were similar. The differences between the PCR and culture results did not change over time and were not affected by regular biocide treatment. This ready-to-use PCR assay for L. pneumophila quantification could permit more timely disinfection of cooling towers.

Air Conditioning↗