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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 775 records · Page 43
All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

Preliminary market analysis for large zeolite crystals

Zeolite crystals are used in the manufacture of countless products today, which utilize their properties of absorption, ion exchange, and catalysis. It was determined that zeolites grown in space could be much larger in size than any of those currently available on Earth. The objective was to identify and examine some of the potential uses for these larger crystals. Of the several industries examined, the medical and nuclear industries offer the greatest potential.

Doblmaier, Thomas↗
NASA NTRS1987

Treatment bed microbiological control

The effects of microbial fouling on treatment bed (TB) performance are being studied. Fouling of activated carbon (AC) and ion exchange resins (IEX) by live and devitalized bacteria can cause decreased capacity for selected sorbates with AC and IEX TB. More data are needed on organic species removal in the trace region of solute sorption isotherms. TB colonization was prevented by nonclassical chemical disinfectant compositions (quaternary ammonium resins) applied in suitable configurations. Recently, the protection of carbon beds via direct disinfectant impregnation has shown promise. Effects (of impregnation) upon bed sorption/removal characteristics are to be studied with representative contaminants. The potential need to remove solutes added or produced during water disinfection and/or TB microbiological control must be investigated.

Janauer, Gilbert E.↗
NASA NTRS1987

Test results of a shower water recovery system

A shower test was conducted recently at NASA-JSC in which waste water was reclaimed and reused. Test subjects showered in a prototype whole body shower following a protocol similar to that anticipated for Space Station. The waste water was purified using reverse osmosis followed by filtration through activated carbon and ion exchange resin beds. The reclaimed waste water was maintained free of microorganisms by using both heat and iodine. This paper discusses the test results, including the limited effectiveness of using iodine as a disinfectant and the evaluation of a Space Station candidate soap for showering. In addition, results are presented on chemical and microbial impurity content of water samples obtained from various locations in the water recovery process.

Verostko, Charles E.↗
NASA NTRS1988

REE in the Great Whale River estuary, northwest Quebec

A report on REE concentrations within the estuary of the Great Whale River in northwest Quebec and in Hudson Bay is given, showing concentrations which are less than those predicted by conservative mixing of seawater and river water, indicating removal of REE from solution. REE removal is rapid, occurring primarily at salinities less than 2 percent and ranges from about 70 percent for light REE to no more than 40 percent for heavy REE. At low salinity, Fe removal is essentially complete. The shape of Fe and REE vs. salinity profiles is not consistent with a simple model of destabilization and coagulation of Fe and REE-bearing colloidal material. A linear relationship between the activity of free ion REE(3+) and pH is consistent with a simple ion-exchange model for REE removal. Surface and subsurface samples of Hudson Bay seawater show high REE and La/Yb concentrations relative to average seawater, with the subsurface sample having a Nd concentration of 100 pmol/kg and an epsilon(Nd) of -29.3; characteristics consistent with river inputs of Hudson Bay. This indicates that rivers draining the Canadian Shield are a major source of nonradiogenic Nd and REE to the Atlantic Ocean.

Goldstein, Steven J.↗
NASA NTRS1988

The virtual cathode as a transient double sheath

The two-dimensional plasma potential measurements are given of a space-charge dominated double sheath near a hot cathode. Laboratory data show that a virtual cathode is a self-consistent solution only for a transient cathode-plasma system. Slow charge exchange ions get trapped in the potential dip that forms the virtual cathode and eventually destroy it.

Intrator, T.↗
NASA NTRS1988

Zeolites on Mars: Possible environmental indicators in soils and sediments

Weathering products should serve as indicators of weathering environments and may provide the best evidence of the nature of climate change on Mars. No direct mineralogical measurements of Martian regolith were performed by the Viking missions, but the biology and X-ray fluorescence experiments provided some information on the physiochemical properties of Martian regolith. Most post-Viking studies of candidate weathering products have emphasized phyllosilicates and Fe-oxides; zeolites are potentially important, but overlooked, candidate Martian minerals. Zeolites would be important on Mars for three different reasons. First, they are major sinks of atmospheric gases and, per unit mass, are stronger and more efficient sorbents than are phyllosilicates. Secondly, they can be virtually unique sorbents and shelters for organic compounds and possible catalysts for organic-based reactions. Finally, their exchangeable ions are good indicators of the chemical properties of solutions with which they have communicated. Accordingly, the search for information on past compositions of the Martian atmosphere and hydrosphere should find zeolites to be rich repositories.

Ming, D. W.↗
NASA NTRS1988

Significance of elevated K/Rb ratios in lower crustal rocks

The granulite uncertainty principle, which states that it is difficult or impossible to determine with certainty the maximum geopressure and geotemperature that a granulite has experienced, is addressed. Also, geochemical fingerprinting cannot always be used reliably in the nebulous region that is transitional between metamorphic and igneous environments. Ion exchange thermometers are typically useful to approximately 800 C in slowly cooled plutonic rocks unless one uses a reintegration technique on unmixed minerals, or unless a metastable mineral assemblage can be observed. It is argued that in most granulites, fossil temperatures are typically obliterated by reequilibration and/or deformation during slow cooling. Granulite metamorphism may be further complicated by the common association with igneous activity. The previously-used geochemical indicators such as high K/Rb ratios and LIL depletion may not be strictly the result of granulite facies metamorphic depletion, but also may result from igneous processes, which depend on bulk and mineral compositions and on the mineralogy of the protolith. Detailed geologic mapping will be the ultimate arbitrator of whether a given geochemical signature is the result of igneous or metamorphic processes.

Frost, B. Ronald↗
NASA NTRS1989

The search for and identification of amino acids, nucleobases and nucleosides in samples returned from Mars

An investigation of the returned Mars samples for biologically important organic compounds, with emphasis on amino acid, the puring and pyrimidine bases, and nucleosides is proposed. These studies would be conducted on subsurface samples obtained by drilling past the surface oxidizing layer with emphasis on samples containing the larges quantities of organic carbon as determined by the rover gas chromatographic mass spectrometer (GCMS). Extraction of these molecules from the returned samples will be performed using the hydrothermal extraction technique described by Cheng and Ponnamperuma. More rigorous extraction methods will be developed and evaluated. For analysis of the extract for free amino acids or amino acids present in a bound or peptidic form, aliquots will be analyzed by capillary GCMS both before and after hydrolysis with 6N hydrochloric acid. Establishment of the presence of amino acids would then lead to the next logical step which would be the use of chiral stationary gas chromatography phases to determine the enatiomeic composition of the amino acids present, and thus potentially establish their biotic or abiotic origin. Confirmational analyses for amino acids would include ion-exchange and reversed-phase liquid chromatographic analysis. For analyses of the returned Mars samples for nucleobases and nucleosides, affinity and reversed-phase liquid chromatography would be utilized. This technology coupled with scanning UV detection for identification, presents a powerful tool for nucleobase and nucleoside analysis. Mass spectrometric analysis of these compounds would confirm their presence in samples returned form Mars.

Gehrke, Charles W.↗
NASA NTRS1988

Test results on re-use of reclaimed shower water: Summary

A microgravity whole body shower (WBS) and waste water recovery systems (WWRS) were evaluated in three separate closed loop tests. Following a protocol similar to that anticipated for the U.S. Space Station, test subjects showered in a prototype whole body shower. The WWRS processes evaluated during the test series were phase change and reverse osmosis (RO). A preprototype Thermoelectric Integrated Hollow Fiber Membrane Evaporation Subsystem phase change process was used for the initial test with chemical pretreatment of the shower water waste input. The second and third tests concentrated on RO technologies. The second test evaluated a dynamic RO membrane consisting of zirconium oxide polyacrylic acid (ZOPA) membranes deposited on the interior diameter of 316L porous stainless steel tubes while the final test employed a thin semipermeable RO membrane deposited on the interior surface of polysulfone hollow fibers. All reclaimed water was post-treated for purity using ion exchange and granular activated carbon beds immediately followed by microbial control treatment using both heat and iodine. The test hardware, controls exercised for whole body showering, types of soaps evaluated, shower subject response to reclaimed water showering, and shower water collection and chemical pretreatment (if required) for microbial control are described. The WWRS recovered water performance and the effectiveness of the reclaimed water post-treatment techniques used for maintaining water purity and microorganism control are compared. Results on chemical and microbial impurity content of the water samples obtained from various locations in the shower water reuse system are summarized.

Verostko, C. E.↗
NASA NTRS1988

A fuel cell energy storage system for Space Station extravehicular activity

The development of a fuel cell energy storage system for the Space Station Extravehicular Mobility Unit (EMU) is discussed. The ion-exchange membrane fuel cell uses hydrogen stored as a metal hydride. Several features of the hydrogen-oxygen fuel cell are examined, including its construction, hydrogen storage, hydride recharge, water heat, water removal, and operational parameters.

Rosso, Matthew J., Jr.↗
NASA NTRS1990

Stability Of A Carbon-Dioxide-Removing Resin

Report describes experiments determing long-term chemical stability of IRA-45, commerical ion-exchange resin candidate for use in removing CO2 from atmosphere of Space Station. In proposed system, cabin air passes through resin, and acidic CO2 absorbed by weakly-basic hydrated diethylenetriamine bonded to porous resin substrate. When resin absorbs all CO2, disconnects from airstream and heated with steam to desorb CO2. Resin reuseable. Removed by post-treating process air with phosphoric acid on charcoal. Other chemicals removed by trace-contaminant-control subsystem of Space Station.

Wydeven, Theodore↗
NASA NTRS1989

Application of biocatalysts to Space Station ECLSS and PMMS water reclamation

Immobilized enzyme reactors have been developed and tested for potential water reclamation applications in the Space Station Freedom Environmental Control and Life Support System (ECLSS) and Process Materials Management System (PMMS). The reactors convert low molecular weight organic contaminants found in ECLSS and PMMS wastewaters to compounds that are more efficiently removed by existing technologies. Demonstration of the technology was successfully achieved with two model reactors. A packed bed reactor containing immobilized urease was found to catalyze the complete decomposition of urea to by-products that were subsequently removed using conventional ion exchange results. A second reactor containing immobilized alcohol oxidase showed promising results relative to its ability to convert methanol and ethanol to the corresponding aldehydes for subsequent removal. Preliminary assessments of the application of biocatalysts to ECLSS and PMMS water reclamation sytems are presented.

Jolly, Clifford D.↗
NASA NTRS1989

Biofilm formation and control in a simulated spacecraft water system - Interim results

The ability of iodine to control microbial contamination and biofilm formation in spacecraft water distribution systems is studied using two stainless steel water subsystems. One subsystem has an iodine level of 2.5 mg/L maintained by an iodinated ion-exchange resin. The other subsystem has no iodine added. Stainless steel coupons are removed from each system to monitor biofilm formation. Results from the first six months of operation indicate that 2.5 mg/L of iodine has limited the number of viable bacteria that can be recovered from the iodinated subsystem. Epifluorescence microscopy of the coupons taken from this subsystem, however, indicates some evidence of microbial colonization after 15 weeks of operation. Numerous bacteria have been continually removed from both the water samples and the coupons taken from the noniodinated subsystem after only 3 weeks of operation.

Schultz, John R.↗
NASA NTRS1990

Recent experiences with iodine water disinfection in Shuttle

Microbial proliferation in the STS potable water system is prevented by maintaining a 2-5 ppm iodine residual. The iodine is added to fuel cell water by an iodinated ion exchange resin in the Microbial Check Valve (MCV). Crew comments indicated excessive iodine in the potable water. To better define the problem, a method of in-flight iodine analysis was developed. Inflight analysis during STS-30 and STS-28 indicated iodine residuals were generally in the 9-13 ppm range. It was determined that the high iodine residual was caused by MCV influent temperatures in excess of 120 F. This is well above the MCV operating range of 65-90 F. The solution to this problem was to develop a resin suitable for the higher temperatures. Since 8 months were required to formulate a MCV resin suitable for the higher temperatures, a temporary solution was necessary. Two additional MCV's were installed on the chilled and ambient water lines leading into the galley to remove the excess iodine. These reduced the iodine residual to 3-4 ppm during STS-33, STS-34, STS-36 and STS-32. A high-temperature resin was formulated and initially flown on STS-31.

Gibbons, Randall E.↗
NASA NTRS1991

Source And Sink Of Iodine For Drinking Water

Proposed system for controlling concentration of iodine in potable water exploits temperature dependence of equilibrium partition of iodine between solution in water and residence in ion-exchange resin. Used to maintain concentration of iodine sufficient to kill harmful microbes, but not so great to make water unpalatable. Requires little attention, yet controls concentration of iodine more precisely than iodination and deiodination by manual techniques. Conceived for use aboard spacecraft, system has terrestrial applications in regions where water must be kept potable, resupply difficult, and system must operate largely unattended.

Sauer, Richard L.↗
NASA NTRS1991

Physical/chemical closed-loop water-recycling

Water needs, water sources, and means for recycling water are examined in terms appropriate to the water quality requirements of a small crew and spacecraft intended for long duration exploration missions. Inorganic, organic, and biological hazards are estimated for waste water sources. Sensitivities to these hazards for human uses are estimated. The water recycling processes considered are humidity condensation, carbon dioxide reduction, waste oxidation, distillation, reverse osmosis, pervaporation, electrodialysis, ion exchange, carbon sorption, and electrochemical oxidation. Limitations and applications of these processes are evaluated in terms of water quality objectives. Computerized simulation of some of these chemical processes is examined. Recommendations are made for development of new water recycling technology and improvement of existing technology for near term application to life support systems for humans in space. The technological developments are equally applicable to water needs on Earth, in regions where extensive water recycling is needed or where advanced water treatment is essential to meet EPA health standards.

Herrmann, Cal C.↗
NASA NTRS1991

SPE (tm) water electrolyzers in support of mission from planet Earth

During the 1970's, the Solid Polymer Electrolyte (SPE) water electrolyzer, which uses ion exchange membranes as its sole electrolyte, was developed for nuclear submarine metabolic oxygen production. SPE water electrolyzer developments included operation at up to 3,000 psia and at current densities in excess of 1,000 amps per square foot. The SPE water electrolyzer system has accumulated tens of thousands of system hours with the Navies of both the United States and the United Kingdom. During the 1980's, the basic SPE water electrolyzer cell structure developed for the Navies was incorporated into several demonstrators for NASA's Space Station Program. Among these were: (1) the SPE regenerative fuel cell for electrical energy storage; (2) the SPE water electrolyzer for metabolic oxygen production; and (3) the high pressure SPE water electrolyzer for reboost propellant production. In the 1990's, emphasis will be the development of SPE water electrolyzers for Mission from Planet Earth. Currently defined potential applications for the SPE water electrolyzer include: (1) SPE water electrolyzers operating at high pressure as part of a regenerative fuel cell extraterrestrial surface energy storage system; (2) SPE water electrolyzers for propellant production from extraterrestrial indigenous materials; and (3) SPE water electrolyzers for metabolic oxygen and potable water production from reclaimed water.

J F McElroy↗
NASA NTRS1989

Life support systems research at the Johnson Space Center

The bioregenerative life support systems research at Johnson Space Center focuses on the use of lunar regolith as a plant growth medium. Current dissolution experiments are being conducted to ascertain the response of lunar regolith to various solvents and weathering environments. The transformation of lunar minerals into minerals such as zeolites which would be more conducive to plant growth is also investigated. A study is currently underway to examine the ability of zeolite/apatite mixtures to provide N, P, and K through dissolution and ion exchange. The development and characterization of simulated lunar regolith for preliminary experimentation are also discussed. The life support systems technology used on the Mercury, Gemini, Apollo, and Shuttle missions is reviewed and current research on regenerative life support systems technology for potential use in Space Station Freedom is discussed.

Henninger, D. L.↗