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A hydrogen economy is an increasingly popular solution to lower global carbon dioxide emissions. Previous research has been focused on the economic conditions necessary for hydrogen to be cost competitive, which tends to neglect the effectiveness of greenhouse gas mitigation for the very solutions proposed. The holistic carbon footprint assessment of hydrogen production, distribution, and utilization methods, otherwise known as “well-to-wheels” carbon intensity, is critical to ensure the new hydrogen strategies proposed are effective in reducing global carbon emissions. When looking at these total carbon intensities, however, there is no single clear consensus regarding the pathway forward. When comparing the two fundamental technologies of steam methane reforming and electrolysis, there are different scenarios where either technology has a “greener” outcome.

Heat pipes, loop heat pipes and capillary pumped loops are heat transfer devices driven by capillary forces with high-effectiveness & performance, offering high-reliability & flexibility in varying g-environments. They are suitable for spacecraft thermal control where the mass, volume, and power budgets are very limited. The Canadian Space Agency is developing loop heat pipe hardware aimed at understanding the thermal performance of two-phase heat transfer devices and in developing numerical simulation techniques using thermo-hydraulic mathematical models, to enable development of novel thermal control technologies. This loop heat pipe consists of a cylindrical evaporator, compensation chamber, condenser along with vapor and liquid lines, which can be easily assembled/disassembled for test purposes. This laboratory setup is especially designed to enable the visualization of fluid flow and phase change phenomena.

Bioregenerative systems for removal of gaseous contaminants are desired for long-term space missions to reduce the equivalent system mass of the air cleaning system. This paper describes an innovative design of a new biofiltration test lab for investigating the capability of biofiltration process for removal of ersatz multi-component gaseous streams representative of spacecraft contaminants released during long-term space travel. The lab setup allows a total of 24 bioreactors to receive identical inlet waste streams at stable contaminant concentrations via use of permeations ovens, needle valves, precision orifices, etc. A unique set of hardware including a Fourier Transform Infrared (FTIR) spectrometer, and a data acquisition and control system using LabVIEW™ software allows automatic, continuous, and real-time gas monitoring and data collection for the 24 bioreactors. This lab setup allows powerful factorial experimental design.

The Sabatier reactor is an exothermic, heterogeneous catalytic reactor that has the function of reducing carbon dioxide to methane and water vapor. Sabatier reactor operation is affected by gravity through the effects of buoyant forces. The buoyant forces affect the transfer of heat and can be significant in determining the temperatures of the various portions of the reactor. The temperatures then affect the fundamental processes such as the chemical reaction rate. This paper presents the results of zero “G” computer model simulations of Sabatier reactor operation. Groundbase experiments were made for various manned loadings under normal ambient and gravity (l-G) conditions and were correlated with normal gravity simulations. The zero “G” simulations show the reactor will run significantly hotter in a zero “G” environment if cooling air flow is not increased to compensate for the loss of natural convections.

The kinetics of the Sabatier methanation reaction, the reduction of carbon dioxide with hydrogen to methane and water, was investigated for 58 percent nickel on kieselguhr catalyst and 20 percent ruthenium on alumina catalyst. Differential rate data from an experimental program were correlated with a power function rate equation both for forward and reverse reactions. The kinetic parameters of activation energy, frequency rate constant and reaction order were determined for the rate equation. The values of these parameters were obtained from an Arrhenius plot of the experimental differential rate data. Also the carbon monoxide side reaction effect was measured and included in the correlation of parameters. The reaction was found to fit the rate equation experimentally within the temperature range 421°K, where the reaction effectively begins, to 800°K where the reaction rate drops and departs from the rate equation form.

The feasibility of a near-complete and biosafe conversion of human- and food waste into biogas was investigated in the context of ESA’s MELiSSA loop (Micro Ecological Life Support System Alternative). The treatment comprises of a series of processes, i.e. a mesophilic lab-scale CSTR (continuously stirred tank reactor), an upflow biofilm reactor, a fibre liquefaction reactor containing the rumen bacterium Fibrobacter succinogenes and a hydrothermolysis system in near-critical water. In the one-stage CSTR, a biogas yield of 75% with a specific biogas production of 0.37 L biogas g-1 added VS (volatile suspended solids) at a HRT (hydraulic retention time) of 15 to 25 days was obtained. When the SRT (solid retention time) was uncoupled from the HRT, and all solids were completely retained in the methane reactor, a more complete biogas conversion was observed at a SRT of above 20 days, corresponding to a 10% increase of degradation on a total COD basis.

This specification covers methyl alcohol in the form of a liquid.

This specification covers methyl alcohol 1n the form of a liquid.

This specification covers methyl alcohol in the form of a liquid.

This specification covers mixtures of methyl alcohol or ethyl alcohol, or both, with water in the form of liquids.

This specification covers mixtures of methyl alcohol and/or ethyl alcohol, with water in the form of liquids.

This specification covers mixtures of methyl alcohol and/or ethyl alcohol with water in the form of liquids.

After the launch to the ISS (International Space Station) with The Space Shuttle flight STS 118 13A.1 on August 9th 2007 and the accommodation in the US lab Destiny, the air quality monitor ANITA (Analysing Interferometer for Ambient Air) has been successfully put into operation. ANITA is a technology demonstrator flight experiment being able to continuously monitor with high time resolution the air conditions within the crewed cabins of the ISS. The system has its origin in a long term ESA technology development programme. The ANITA mission itself is an ESA-NASA cooperative project. ESA is responsible for the provision of the HW, the data acquisition and data evaluation. NASA's responsibilities are launch, accommodation in the US Lab Destiny, operation and data download. The ANITA air analyser is currently calibrated to detect and quantify online and with high time resolution 33 gases simultaneously with down to sub-ppm detection limits.

This standard describes test methods to determine the application and performance properties of two-component polysulfide or polythioether sealing compounds. It shall be used in conjunction with AS5127.