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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 127 records · Page 7

Time-resolved tracking of cellulose biosynthesis and assembly during cell wall regeneration in live Arabidopsis protoplasts

Cellulose, the most abundant polysaccharide on earth composing plant cell walls, is synthesized by coordinated action of multiple enzymes in cellulose synthase complexes embedded within the plasma membrane. Multiple chains of cellulose fibrils form intertwined extracellular matrix networks. It remains largely unknown how newly synthesized cellulose is assembled into an intricate fibril network on cell surfaces. Here, we have established an in vivo time-resolved imaging platform to continuously visualize cellulose biosynthesis and fibril network assembly onArabidopsis thalianaprotoplast surfaces as the primary cell wall regenerates. Our observations provide the basis for a model of cellulose fibril network development in protoplasts driven by an interplay of multiscale dynamics that includes rapid diffusion and coalescence of nascent cellulose fibrils, processive elongation of single fibrils, and cellulose fibrillar network rearrangement during maturation. This study provides fresh insights into the dynamic and mechanistic aspects of cell wall synthesis at the single-cell level.

Science & Technology - Other Topics↗

Cooperative carbon capture and steam regeneration with tetraamine-appended metal–organic frameworks

Natural gas has become the dominant source of electricity in the United States, and technologies capable of efficiently removing carbon dioxide (CO 2 ) from the flue emissions of natural gas–fired power plants could reduce their carbon intensity. However, given the low partial pressure of CO 2 in the flue stream, separation of CO 2 is particularly challenging. Taking inspiration from the crystal structures of diamine-appended metal–organic frameworks exhibiting two-step cooperative CO 2 adsorption, we report a family of robust tetraamine-functionalized frameworks that retain cooperativity, leading to the potential for exceptional efficiency in capturing CO 2 under the extreme conditions relevant to natural gas flue emissions. The ordered, multimetal coordination of the tetraamines imparts the materials with extraordinary stability to adsorption-desorption cycling with simulated humid flue gas and enables regeneration using low-temperature steam in lieu of costly pressure or temperature swings.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Anodic Conversion of Cyclohexane, Methylcyclohexane, and 2-Propanol: Towards a Regenerable Liquid-Fed Fuel Cell

Liquid Organic Hydrogen Carriers (LOHCs) are promising for hydrogen and energy storage but require endothermic catalytic dehydrogenation. An alternative approach is a regenerable liquid-fed fuel cell which spontaneously converts an organic carrier from its hydrogen-rich to hydrogen-lean form while generating electrical power. The anodic electrooxidation of cyclohexane, methylcyclohexane and 2-propanol in a high temperature polybenzimidazole/phosphoric acid (PBI/PA) PEM fuel cell was investigated along with a quantitative analysis of reaction products. Cyclohexane and methylcyclohexane were predominantly converted to CO 2 with only a trace formation of the corresponding aromatic and cyclic olefin byproducts. This near-to-complete oxidation of the fuels is in sharp contrast to previous reports of a selective conversion of cyclohexane to benzene, with no CO 2 byproducts. In experiments with 2-propanol, acetone was produced, with diisopropylether, propylene and CO 2 as only minor side products. However, the extent of CO 2 formation greatly increased at higher current densities.

25 ENERGY STORAGE↗

DEVAP-EDDR-TES (Simulation framework for a desiccant assisted air conditioning system with heat pump regeneration and energy storage) [SWR-24-66]

This software is a simulation framework that models a load flexible air conditioner system. The system consists of an evaporatively cooled liquid desiccant air conditioner (eLD-AC) subsystem, an electrically driven desiccant regenerator (EDDR) subsystem, and a stratified liquid desiccant storage (SLDS) subsystem. The software can be used to 1) predict the steady-state performance of the system given user-specified convergence criteria; 2) predict the dynamic performance of the entire system over a typical drive cycle operation subjected to user-specified building thermal loads and desired electrical load profile; 3) evaluate the synergy of all three subsystems operating altogether and improve the energy storage control strategy.

Huang, Ransisi↗

Low Regeneration Temperature Sorbents for Direct Air Capture of CO 2

Susteon Inc., in partnership with University of Wyoming and SoCalGas, successfully met all major technical objectives to (1) scale up the ionic liquid catalyst for amine-based sorbents for improved desorption and absorption kinetics, (2) evaluate the catalyzed amine-based sorbents for direct CO 2 capture process to determine CO 2 adsorption and desorption rates and energy requirements, and (3) based on the experimental results, develop a conceptual process design to perform a preliminary economic assessment to evaluate the potential for DAC process cost reduction using the catalyzed sorbents. Amine doped solid sorbents are effective for DAC applications and can be regenerated by heat or by a combination of heat, steam, and vacuum. The best sorbent composition identified was polyethyleneimine (PEI) on fumed silica with 200 ppm ionic liquid catalyst. This sorbent formulation was shown to have a CO 2 breakthrough capacity twice that of the non-catalyzed sorbent, in laboratory tests with air at 75% relative humidity (RH). The CO 2 adsorption rate was also 40% higher than that of the non-catalyzed sorbent. This type of sorbents has the attributes required for lowering the overall cost of DAC with high CO 2 capacity and high rate of adsorption. The combination of an industrially utilized amine-based sorbent with a highly active catalyst to form a new class of materials for DAC provides a technically viable pathway for reducing the cost of DAC to <$100/tonne of CO 2 . Laboratory measurements show that the silica/PEI (polyethyleneimine) sorbents with 100 ppm of ionic liquid catalyst have almost 100% higher CO 2 cyclic capacity and 40% higher adsorption rate. Generally, CO 2 desorption occurred at higher temperatures with a rate of desorption 10 times faster than adsorption (which occurred at ambient conditions). Therefore, adsorption rate is a much more important factor in the cost of DAC because it is directly linked to the CAPEX of the total system and the cycle time (i.e., sorbent productivity in ton/day of CO 2 captured per unit volume of the air contactor). An initial process design, coupled with techno-economic analysis, based on optimal experimental results and preliminary resulting from structured sorbent testing, showed a path to lower the DAC cost from the current cost of over $200/tonne CO 2 to less than $100/tonne with a scale-up, mature state of the technology, with projected material and process improvements. These results demonstrate the effectiveness of the catalyst in silica/PEI sorbents in enhancing sorbents’ CO 2 working capacity, in (a) increasing the rate of adsorption and desorption, and (b) in lowering the CAPEX and OPEX of the DAC system employing the ionic liquid catalyzed sorbents.

01 COAL, LIGNITE, AND PEAT↗

Non-Stoichiometric High Entropy Spinel Oxides as Regenerable Catalysts for Methane Dry Reforming

In this work, novel high entropy oxides were developed and applied as catalysts in the methane dry reforming reaction. Catalytic results show high activity and regenerable structure of the high entropy oxides but degradation of simple nickel aluminate spinels commonly applied to this reaction. A proof-of-concept experiment demonstrated heating of the high entropy oxide catalyst to reaction relevant temperatures using concentrating solar power equipment.

Riva, Andrew↗

Regenerable non-aqueous basic immobilized amine slurries for removal of CO2 from a gaseous mixture and a method of use thereof

The disclosure provides a composition for the separation of CO2 from a gaseous mixture and a method of use thereof. The composition comprises solid Basic Immobilized Amine Sorbents (BIAS) suspended in silicone oil. The method of use comprises contacting the gaseous mixture with a sorbent slurry comprising Basic Immobilized Amine Sorbents (BIAS) and silicone oil to at least partially absorb the CO2 from the gaseous mixture, and regenerating the BIAS slurry by causing desorption of the CO2.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Low cost immobilized amine regenerable solid sorbents

A method of modifying a chemical interaction between a functional group of an immobilized amine in a solid sorbent composition and a compound that chemically interacts with the functional group to reduce the heat required to desorb the compound from the solid sorbent. A method of inhibiting degradation of an immobilized amine in an immobilized amine solid sorbent. Compositions and methods of use of a low-cost regenerable immobilized amine solid sorbent resistant to degradation.

Chuang, Steven S. C.↗

Systems and methods of long-duration energy storage and regeneration of energy-bearing redox pairs

Described herein are systems and methods of storing and delivering electrical using hydrogen at low-cost and for long-durations. The systems and methods use energy-bearing redox pairs that electrochemically bear energy through decoupled hydrogen and oxygen consumption and/or evolution reactions, which are typically associated with fuel cells. Each species of the energy-bearing redox pair is associated with a standard electrode potential within a water electrolysis voltage window for the electrolyte solution. Electrical energy delivery, hydrogen generation, electrolyte regeneration, or combinations thereof can be performed by logically or physically separated unit operations in a continuous manner, batch manner, or semi-batch manner facilitated by the energy-bearing redox pair.

08 HYDROGEN↗

Regenerable battery electrode

A binder-free, self-supporting electrode including an electrochemically active material in the absence of a binder and a current collector is claimed. The electrochemically active material is a self-supporting transition metal oxide. A method of regenerating the electrode to restore capacity of the electrode is also claimed.

Takeuchi, Esther Sans↗

CBP/P300 Inhibitors Mitigate Radiation-Induced GI Syndrome by Promoting Intestinal Stem Cell-Mediated Crypt Regeneration

Radiation-induced gastrointestinal syndrome (RIGS) is currently the main cause of death for people exposed to a high dose of irradiation during nuclear incidents, and there is currently no approved effective therapy. Here, we found that CBP/P300 inhibitors, with high efficacy and low toxicity, might be promising radiation mitigators that can cure RIGS.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

The role of vascular niche and endothelial cells in organogenesis and regeneration

Highlights: • The vascular niche creates a permissive environment that realize developmental or regenerative programs. • The proximity between endothelium and cells of organs suggests a role of endothelial cells in the organs maturation. • Organs provide cues shaping vascular network structure. The term vascular niche indicate the physical and biochemical microenvironment around blood vessel where endothelial cells, pericytes, and smooth muscle cells organize themselves to form blood vessels and release molecules involved in the recruitment of hematopoietic stem cells, endothelial progenitor cells and mesenchymal stem cells. The vascular niche creates a permissive environment that enables different cell types to realize their developmental or regenerative programs. In this context, the proximity between the endothelium and the new-forming cellular components of organs suggests an essential role of endothelial cells in the organs maturation. Dynamic interactions between specific organ endothelial cells and different cellular conponents are crucial for different organ morphogenesis and function. Conversely, organs provide cues shaping vascular network structure.

60 APPLIED LIFE SCIENCES↗