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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 55 records · Page 3

Sorbent Material Property Requirements for On-Board Hydrogen Storage for Automotive Fuel Cell Systems.

Material properties required for on-board hydrogen storage in cryogenic sorbents for use with automotive polymer electrolyte membrane (PEM) fuel cell systems are discussed. Models are formulated for physical, thermodynamic and transport properties, and for the dynamics of H-2 refueling and discharge from a sorbent bed. A conceptual storage configuration with in-bed heat exchanger tubes, a Type-3 containment vessel, vacuum insulation and requisite balance-of-plant components is developed to determine the peak excess sorption capacity and differential enthalpy of adsorption for 5.5 wt% system gravimetric capacity and 55% well-to-tank (WTT) efficiency. The analysis also determines the bulk density to which the material must be compacted for the storage system to reach 40 g.L-1 volumetric capacity. Thermal transport properties and heat transfer enhancement methods are analyzed to estimate the material thermal conductivity needed to achieve 1.5 kg.min(-1) H-2 refueling rate. Operating temperatures and pressures are determined for 55% WTT efficiency and 95% usable H-2. Needs for further improvements in material properties are analyzed that would allow reduction of storage pressure to 50 bar from 100 bar, elevation of storage temperature to 175-200 K from 150 K, and increase of WTT efficiency to 57.5% or higher.

Ahluwalia, R. K.↗

The Cancer Microbiome: Distinguishing Direct and Indirect Effects Requires a Systemic View

The collection of microbes that live in and on the human body – the human microbiome – can impact on cancer initiation, progression, and response to therapy, including cancer immunotherapy. The mechanisms by which microbiomes impact on cancers can yield new diagnostics and treatments, but much remains unknown. The interactions between microbes, diet, host factors, drugs, and cell–cell interactions within the cancer itself likely involve intricate feedbacks, and no single component can explain all the behavior of the system. Understanding the role of host-associated microbial communities in cancer systems will require a multidisciplinary approach combining microbial ecology, immunology, cancer cell biology, and computational biology – a systems biology approach.

Xavier, Joao B.↗

Support requirements for remote sensor systems on unmanned planetary missions. Appendix A: Support requirement summary tables, phase 3

An appendix containing one page summary tables of sensor observation objectives, measurement capabilities, support requirments, and worth values is presented. Tables are arranged according to (1) sensor type number, (2) flyby mission number, (3) for multi-planet missions, in order of increasing distance from the sun, (4) for orbiter mission, by planets in order of increasing distance from the sun, and (5) by orbit number.

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Earth resources requirements Skylab missions SL-1/SL-2, SL-3, and SL-4. Appendix B: Mission requirements

Earth resources requirements to be investigated by Skylab missions 1 through 4 are presented tabularly. Areas to be investigated include: (1) agriculture, range, and forestry; (2) geology; (3) continental water resources; (4) ocean investigations; (5) atmospheric investigations; (6) coastal zones, shoals, and bays; (7) remote sensing techniques; and (8) cartography.

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Study of space shuttle EVA/IVA support requirements. Volume 5: Requirements study for space shuttle emergency 4 support

The requirements for space shuttle emergency intravehicular activity support equipment are discussed. The potential emergencies considered are: (1) contaminated atmosphere, (2) accidental decompression, (3) inability to re-enter, and (4) crewman stranded. Contingency life support systems are described and the effectiveness of each emergency procedure is analyzed.

Copeland, R. J.↗

Task 4 supporting technology. Densification requirements definition and test objectives. Propellant densification requirements definition

The primary challenge of the X-33 CAN is to build and test a prototype LO2 and LH2 densification ground support equipment (GSE) unit, and perform tank thermodynamic testing within the 15 month phase 1 period. The LO2 and LH2 propellant densification system will be scaled for the IPTD LO2 and LH2 tank configurations. The IPTD tanks were selected for the propellant technology demonstration because of the potential benefits to the phase 1 plan: tanks will be built in time to support thermodynamic testing; minimum cost; minimum schedule risk; future testing at MSFC will build on phase 1 data base; and densification system will be available to support X-33 and RLV engine test at IPTD. The objective of the task 1 effort is to define the preliminary requirements of the propellant densification GSE and tank recirculation system. The key densification system design parameters to be established in Task 1 are: recirculation flow rate; heat exchanger inlet temperature; heat exchanger outlet temperature; maximum heat rejection rate; vent flow rate (GN2 and GH2); densification time; and tank pressure level.

Lak, Tibor↗