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Silicone materials for space and aerospace applications are continually in development and evaluation to limit and reduce the potential for outgassing contamination while maintaining essential physical and chemical characteristics. Several agencies, such as NASA, historically recommend the American Society for Testing and Materials ASTM E595 ["Standard Test Method for Total Mass Loss and Collected Condensable Materials from Outgassing in a Vacuum Environment," ASTM International, Std. ASTM E595, Alexandria, VA, 2007] test results of less than or equal to 1.0% total mass loss and less than or equal to 0.1% collected volatile condensable material. These levels provide an industry screening level for the acceptance or rejection of controlled-volatility materials for space applications. By a comparison of controlled-volatility product CV10-2568 and ultra-low-outgassing product SCV-2585, cured physical properties and outgassing profiles of these two products demonstrate that when incorporating specific fillers, the cured physical properties can remain consistent while still providing exceptional outgassing characteristics. [ABSTRACT FROM AUTHOR]

Industrial and agricultural off-gas streams are comprised of numerous volatile compounds, many of which have substantially different odorous properties. State-of-the-art waste-gas treatment includes the characterization of these molecules and is directed at, if possible, either the avoidance of such odorants during processing or the use of existing standardized air purification techniques like bioscrubbing or afterburning, which however, often show low efficiency under ecological and economical regards. Selective odor separation from the off-gas streams could ease many of these disadvantages but is not yet widely applicable. Thus, the aim of this paper is to identify possible model substances in selective odor separation research from 155 volatile molecules mainly originating from livestock facilities, fat refineries, and cocoa and coffee production by knowledge-based methods. All compounds are examined with regard to their structure and information-content using topological and information-theoretical indices. Resulting data are fitted in an observation matrix, and similarities between the substances are computed. Principal component analysis and k-means cluster analysis are conducted showing that clustering of indices data can depict odor information correlating well to molecular composition and molecular shape. Quantitative molecule describtion along with the application of such statistical means therefore provide a good classification tool of malodorant structure properties with no thermodynamic data needed. The approximate look-alike shape of odorous compounds within the clusters suggests a fair choice of possible model molecules. [ABSTRACT FROM AUTHOR]

When a US wastewater treatment plant in South Carolina saw lower flows than expected, due to a delayed housing project, the facility experienced repeated vapour lock resulting in higher operational and chemical costs. The manual dilution operation resulted in increased operational and chemical costs, so a solution was sought in digital dosing technology. [ABSTRACT FROM AUTHOR]