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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 109 records · Page 6

Ligand-Functionalized Polymer Membranes for Selective Ion Separations

Selective ion separations are central to technologies spanning water purification, resource recovery, and clean energy. Conventional polymer membranes, which rely on steric hindrance or Donnan exclusion, struggle to discriminate between chemically similar ions in high-ionic-strength environments. Ligand-functionalized membranes offer a transformative strategy by embedding molecular recognition directly into polymer matrices, enabling selective complexation and transport. Here, this Viewpoint highlights the structure–function relationships underlying ligand-mediated ion separation, emphasizing the interplay of dehydration penalties, ligand coordination, and nanoscale confinement. We discuss design principles, denticity, donor identity, rigidity, and spatial organization, alongside the permeability–selectivity trade-off, multicomponent effects, and stability challenges. Finally, we outline emerging strategies, from bioinspired ligands to computationally guided design, that chart a path toward next-generation membranes for precise and energy-efficient ion separations.

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Cation selectivities in zwitterion grafted nanopores: effect of zwitterion architecture

Selective separation of monovalent cations is a critical challenge in applications such as water purification and lithium recovery from salt brines. Cross-linked zwitterionic amphiphilic copolymer (ZAC-X) membranes have gained attention for their exceptional anion permselectivity, attributed to self-assembled zwitterion-lined nanodomains that interact preferentially with anions according to their hydrated radii r hyd . However, these membranes show minimal selectivity among monovalent cations, despite significant differences in their hydration structures, motivating studies on the underlying mechanisms of cation transport and selectivity in this family of materials. In this study, we conducted molecular dynamics simulations of aqueous salt solutions within zwitterion-functionalized nanopores to elucidate the influence of dipole orientation of the zwitterionic (ZI) ligands on cation diffusivities, partitioning, and permeabilities. To this end, we examined two contrasting ZI ligand architectures: Motif A (surface–cation–anion, S–ZI + –ZI − ) and Motif B (surface–anion–cation, S–ZI − –ZI + ). Our results show that in Motif A, the sulfonate groups of the ZI ligands are localized near the pore center radially, leading to strong electrostatic interactions with small bare cations (Mg 2+ and Li + ). This configuration results in high cation partitioning but low cation diffusion, maintaining solution-diffusion tradeoff typical of functionalized membranes. In contrast, Motif B show that sulfonate groups shift radially toward the mid-region of the pore. This shift, especially for small bare cations, introduces steric constraints that weaken their interactions with the sulfonate groups, thereby enhancing hydration and lowering partitioning, while still maintaining their low self-diffusivity. These findings establish zwitterion dipole orientation as a powerful design lever for tuning cation selectivity in membrane systems and offer molecular-level insights for engineering next-generation ion separation materials.

Morishita, Kazuya [Univ. of Texas, Austin, TX (Uni↗

Maximizing sunlight absorption in narrow bandgap semiconducting copper(I) iodides for enhanced photocatalytic dye degradation

Photocatalytic dye degradation leverages sunlight to break down dyes and pigments into safer, simpler molecules. Using a material that can absorb a broad range of the solar spectrum optimizes the speed and efficiency of this process. In this study, we explore a series of new, narrow bandgap copper iodide semiconductors (1.5–1.7 eV) with various dimensionalities (0D to 3D) to evaluate their photocatalytic efficiency in dye degradation. The most effective material achieved 95% degradation within just 27 minutes. Mass spectrometry provided a detailed insight and in-depth understanding into the degradation mechanism. All materials demonstrated excellent stability under ambient conditions, highlighting their promise as eco-friendly candidates for dye degradation in water purification.

Carignan, Gia M. [Rutgers Univ., Piscataway, NJ (U↗

Correlating surface adsorbate configuration and electrochemical performance of IrO 2 during seawater-relevant electrolysis

Seawater electrolysis alleviates freshwater demand to produce clean hydrogen while eliminating the need for water purification steps. The anodic process, seawater oxidation, typically requires high overpotentials and yields low selectivity to oxygen via the oxygen evolution reaction (OER), primarily due to the competing chlorine evolution reaction (CER) and hypochlorite evolution reaction (HCER) in pH-neutral conditions. Here, combining in situ surface-enhanced Raman characterization, grand canonical density functional theory-based calculations, and kinetic Monte Carlo simulations, we report the evolution of surface adsorbate configurations driven by applied potential and pH during seawater-relevant OER over IrO 2 , a highly OER-active and chloride-corrosion-resistant catalyst. As a result, the chemical properties of active sites, and thereby the kinetics of OER and CER/HCER, are effectively tuned. However, it is revealed that there is no optimal combination of potential and pH to achieve both high activity and high selectivity for seawater-relevant OER. To address this limitation, we establish a correlation between activity/selectivity and surface adsorbate configurations, enabling the optimization of highly active and OER-selective IrO 2 -based catalysts in seawater-relevant oxidation by modulating the local adsorbate environment of active sites.

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Analytical methods for bacterial kinetics studies

Methods utilize mathematical equations and models and specialized computer techniques. Techniques apply to food production, complex chemicals production, and polluted water purification.

Edwards, V. E.↗

Potential applications of NASA-developed technology to problems of the environment.

The life-support mission of NASA has the same broad objectives as the national imperatives toward environmental restoration: pure air, clean water, and reuse of resources. The major difference is the vast scale of the environment, compared to the very small scale of spacecraft, even including the largest space stations now projected. For this reason, the devices developed for manned spacecraft life support will be of much less interest than the techniques that have emerged from NASA-sponsored research and development. Several immediate applications in air and water purification can be cited, and several other long-term potential applications may also be considered.

Ross, L. W.↗

A centrifugal method for the evaluation of polymer membranes for reverse osmosis

A rapid and simple method employing the laboratory centrifuge shows promise for evaluation of membrane performance during reverse osmosis. Results are presented for cellulose acetate membranes for rejection of salt and urea dissolved solids. Implications of the study are to rapid screening of membrane performance, use in laboratories with limited facilities, and possible space waste water purification.

Hollahan, J. R.↗

The MIST /MIUS Integration and Subsystems Test/ laboratory - A testbed for the MIUS /Modular Integrated Utility System/ program

The MIUS (Modular Integrated Utility System) concept is to be an energy-conserving, economically feasible, integrated community utility system to provide five necessary services: electricity generation, space heating and air conditioning, solid waste processing, liquid waste processing, and residential water purification. The MIST (MIUS Integration and Subsystem Test) integrated system testbed constructed at the Johnson Space Center in Houston includes subsystems for power generation, heating, ventilation, and air conditioning (HVAC), wastewater management, solid waste management, and control and monitoring. The key design issues under study include thermal integration and distribution techniques, thermal storage, integration of subsystems controls and displays, incinerator performance, effluent characteristics, and odor control.

Beckham, W. S., Jr.↗

Compact bypass-flow filter

Annular filter consisting of stacked rings separates particulates from bypass fluid passing through it in radial direction without slowing down main flow across unimpeded flow of fluid through its center. Applications include fluidized bed reactors, equipment for catalyst operations, and water purification.

Swift, W. G.↗

Reverse osmosis membrane of high urea rejection properties

Polymeric membranes suitable for use in reverse osmosis water purification because of their high urea and salt rejection properties are prepared by generating a plasma of an unsaturated hydrocarbon monomer and nitrogen gas from an electrical source. A polymeric membrane is formed by depositing a polymer of the unsaturated monomer from the plasma onto a substrate, so that nitrogen from the nitrogen gas is incorporated within the polymer in a chemically combined form.

Johnson, C. C.↗

A Unique Photon Bombardment System for Space Applications

The innovative Electromagnetic Radiation Collection and Concentration System (EMRCCS) described is the foundation for the development of a multiplicity of space and terrestrial system formats. The system capability allows its use in the visual, infrared, and ultraviolet ranges of the spectrum for EM collection, concentration, source/receptor tracking, and targeting. The nonimaging modular optical system uses a physically static position aperture for EM radiation collection. Folded optics provide the concentration of the radiation and source autotracking. The collected and concentrated electromagnetic radiation is utilized in many applications, e.g., solar spectrum in thermal and associative photon bombardment applications for hazardous waste management, water purification, metal hardening, hydrogen generation, photovoltaics, etc., in both space and terrestrial segment utilization. Additionally, at the high end of the concentration capability range, i.e., 60,000+, a solar-pulsed laser system is possible.

Klein, E. J.↗

Microcoupon Assay Of Adhesion And Growth Of Bacterial Films

Microbiological assay technique facilitates determination of some characteristics of sessile bacteria like those that attach to and coat interior walls of water-purification systems. Biofilms cause sickness and interfere with purification process. Technique enables direct measurement of rate of attachment of bacterial cells, their metabolism, and effects of chemicals on them. Used to quantify effects of both bactericides and growth-stimulating agents and in place of older standard plate-count and tube-dilution techniques.

Pierson, Duane L.↗

Validated environmental and physiological data from the CELSS Breadboard Projects Biomass Production Chamber. BWT931 (Wheat cv. Yecora Rojo)

This KSC database is being made available to the scientific research community to facilitate the development of crop development models, to test monitoring and control strategies, and to identify environmental limitations in crop production systems. The KSC validated dataset consists of 17 parameters necessary to maintain bioregenerative life support functions: water purification, CO2 removal, O2 production, and biomass production. The data are available on disk as either a DATABASE SUBSET (one week of 5-minute data) or DATABASE SUMMARY (daily averages of parameters). Online access to the VALIDATED DATABASE will be made available to institutions with specific programmatic requirements. Availability and access to the KSC validated database are subject to approval and limitations implicit in KSC computer security policies.

Stutte, G. W.↗

The controlled ecological life support system Antarctic analog project: Analysis of wastewater from the South Pole Station, Antarctica, volume 1

The Controlled Ecological Life Support system (CELSS) Antarctic Analog Project (CAAP) is a joint National Science Foundation (NSF) and NASA project for the development, deployment and operation of CELSS technologies at the Amundsen-Scott South Pole Station. NASA goals are operational testing of CELSS technologies and the conduct of scientific studies to facilitate technology selection and system design. The NSF goals are that the food production, water purification, and waste treatment capabilities which will be provided by CAAP will improve the quality of life for the South Pole inhabitants, reduce logistics dependence, and minimize environmental impacts associated with human presence on the polar plateau. This report presents an analysis of wastewater samples taken from the Amundsen-Scott South Pole Station, Antarctica. The purpose of the work is to develop a quantitative understanding of the characteristics of domestic sewage streams at the South Pole Station. This information will contribute to the design of a proposed plant growth/waste treatment system which is part of the CELSS Antarctic Analog Project (CAAP).

Flynn, Michael T.↗

CELSS Antarctic Analog Project (CAAP): A New Paradigm for Polar Life Support and CELSS Research

The CELSS Antarctic Analog Project (CAAP) is a joint National Science Foundation (NSF) and National Aeronautics and Space Administration (NASA) project for the development, deployment and operation of CELSS technologies at the Amundsen-Scott South Pole Station. CAAP is implemented through the joint NSF/NASA Antarctic Space Analog Program (ASAP), initiated to support the pursuit of future NASA missions and to promote the transfer of space technologies to the NSF. Under a Memorandum of Agreement, the CAAP represents an example of a working dual agency cooperative project. NASA goals are operational testing of CELSS technologies and the conduct of scientific study to facilitate . technology selection, system design and methods development, including human dynamics as required for the operation of a CELSS. Although not fully closed, food production, water purification, and waste recycle and reduction provided by CAAP will improve the quality of life for the South Pole inhabitants, reduce logistics dependence, and minimize environmental impacts associated with human presence on the polar plateau. The CAAP facility will be highly integrated with the new South Pole Station infrastructure and will be composed of a deployed hardware facility and a research activity. This paper will include a description of CAAP and its functionality, conceptual designs, component selection and sizing for the crop growth chamber, crop production expectations, and a brief report on an initial on-site visit. This paper will also provide a discussion of issues associated with power and energy use and the applicability of CAAP to direct technology transfer to society in general and remote communities in particular.

Bubenheim, David L.↗

Beating Back Bacteria

Under a NASA-Johnson Space Center contract, Umpqua Research developed the MCV (Trademark) (Microbial Check Valve) which uses iodinated ion exchange resin used for water purification systems aboard space missions. Using this resin, MRLB International, Inc., developed and commercialized the Dentapure purification cartridge used by dentists nationwide.

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