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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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High efficiency lightweight solar concentrator development - backing, support structures, material electroforming, and tooling
IMP-II and OGO-I measurements on plasma characteristics in transition region between solar wind and geomagnetic field
Vortex arc studies, solar flux and spectral measurements, spacecraft coatings, solar simulation studies, and solar cell radiation effects testing
IMP-II and OGO-I measurements on plasma characteristics in transition region between solar wind and geomagnetic field
The effects of outdoor exposure were determined by comparing standard I-V data obtained for the as-received modules with similar data obtained after removal from the field and cleaning with detergent solution. All modules measured in this way exhibited nonrecoverable degradation in P sub maximum varying from 4 to 7 percent. One module exposed for 41 days exhibited partial cell discoloration, loss of front surface metallization over the discolored portion, and a decrease in P sub maximum of 7 percent, tentatively attributed to cell damage. Measurements before and after cleaning showed a recoverable degradation due to dirt accumulation. This recoverable loss in power was 11 percent after 245 days in the field for one brand of module, 6 percent after 48 days for another brand, and 4 1/2 percent for the third brand.
Earth and solar radiation budget measurements were examined. Sensor calibration and measurement accuracy were emphasized. Past works on the earth's radiation field that must be used in reducing observations of the radiation field were reviewed. Using a finite difference radiative transfer algorithm, models of the angular and spectral dependence of the earth's radiation field were developed.
Meniscus coates tests, back junction formation using a new boron containing liquid, tests of various SiO2 and boron containing liquids, pelletized silicon for replenishment during web growth, and ion implantation compatibility/feasibility study are discussed.
The evolution of a dissipating turbulently viscous disk of gas and dust formed during the collapse of an interstellar cloud fragment and how it relates to the early history of the solar system is discussed. Results from calculations on modelling the inner parts of the primitive solar nebula subject to the assumption of a steady inward flow are given. Other calculations are reviewed which simulate the accretion of a star from an accretion disk. Scenarios for the evolution of the primitive solar nebula and the formation of the Moon as a result of a major collision with the protoearth are described.
Encapsulation materials for solar cells were investigated. The different phases consisted of: (1) identification and development of low cost module encapsulation materials; (2) materials reliability examination; and (3) process sensitivity and process development. It is found that outdoor photothermal aging devices (OPT) are the best accelerated aging methods, simulate worst case field conditions, evaluate formulation and module performance and have a possibility for life assessment. Outdoor metallic copper exposure should be avoided, self priming formulations have good storage stability, stabilizers enhance performance, and soil resistance treatment is still effective.
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Abstract not provided.
This LTSA award funded my research on the origin of stellar X-ray emission and the validity of the solar-stellar analogy. This research broadly addresses the relevance of our current understanding of solar X-ray physics to the interpretation of X-ray emission from stars in general. During the past five years the emphasis has been on space-based X-ray observations of very young stars in star-forming regions (T Tauri stars and protostars), cool solar-like G stars, and evolved high-mass Wolf-Rayet (WR) stars. These observations were carried out primarily with the ASCA and ROSAT space-based observatories (and most recently with Chandra), supplemented by ground-based observations. This research has focused on the identification of physical processes that are responsible for the high levels of X-ray emission seen in pre-main-sequence (PMS) stars, active cool stars, and WR stars. A related issue is how the X-ray emission of such stars changes over time, both on short timescales of days to years and on evolutionary timescales of millions of years. In the case of the Sun it is known that magnetic fields play a key role in the production of X-rays by confining the coronal plasma in loop-like structures where it is heated to temperatures of several million K. The extent to which the magnetically-confined corona interpretation can be applied to other X-ray emitting stars is the key issue that drives the research summarized here.
NASA created the first virtual institute, the NASA Astrobiology Institute (NAI), in 2009 with an aim toward bringing together geographically disparate and multidisciplinary teams toward the goal of answering broad questions in the then-new discipline of astrobiology. With the success of the virtual institute model, NASA then created the NASA Lunar Science Institute (NLSI) in 2008 to address questions of science and human exploration of the Moon, and then the NASA Aeronautics Research Institute (NARI) in 2012 which addresses key questions in the development of aeronautics technologies. With the broadening of NASA's human exploration targets to include Near Earth Asteroids and the moons of Mars as well as the Moon, the NLSI morphed into the Solar System Exploration Research Virtual Institute (SSERVI) in 2012. SSERVI funds domestic research teams to address broad questions at the intersection of science and human exploration, with the underlying principle that science enables human exploration, and human exploration enables science. Nine domestic teams were funded in 2014 for a five-year period to address a variety of different topics, and nine international partners (with more to come) also work with the U.S. teams on a variety of topics of mutual interest. The result is a robust and productive research infrastructure that is not only scientifically productive but can respond to strategic topics of domestic and international interest, and which develops a new generation of researchers. This is all accomplished with the aid of virtual collaboration technologies which enable scientific research at a distance. The virtual institute model is widely applicable to a range of space science and exploration problems.
This Perspective article provides a brief overview of the topic of wind and solar energy droughts (henceforth WSDs). It does not attempt to provide a complete literature review of the subject but rather highlights some of the main concepts associated with WSDs. These include wind and solar energy drought definitions and metrics; meteorological conditions producing WSDs; a comparison of their characteristics with hydrologic droughts and hydropower droughts; model-based and observational datasets useful for WSD analyses; the linkage of WSDs to transmission, storage, and demand response; the potential impacts of WSDs vs energy demand variations; wind and solar flood events; WSD predictability; WSD dependency on climate modes of variability; climate change impacts on WSDs; and the special challenge of evaluating the characteristics of WSDs in developing countries that have limited historical data available. Finally, the manuscript identifies research areas that the authors believe would provide immediate benefit to energy system planners.
The major elements of the NASA manned space station are described, and science activities it could be used for are suggested. The core facilities include at least two major laboratory modules with supporting utilities, including habitation accommodations, docking facilities, power and heat rejection units, and external space and support for attached payloads. A vertically oriented structure, called the Power Tower, is being studied. Scientific accommodations inside the modules include major facility instrumentation for a variety of microgravity research projects, with initial emphasis upon materials research and life sciences. The second element is composed of free-flying satellites operating in orbits near the core station. The third element consists of satellites in polar orbits. One or more large, multi-instrument platforms are planned for Earth observation and solar-terrestrial processes research.
A fast-tracked multifaceted approach that integrated NASA, industry, and academia was successfully executed to advance the novel concept of radiation pressure by means of a thin diffractive film. This pioneering new approach to light sailing was found to offer advantages over reflective sails - especially for missions that include close orbits or a close fly-by of the sun.The research effort included experiments, numerical modeling, and an "incubator meeting" that brought together over 35 researchers and stakeholders to uncover some of the most feasible means of advancing both the TRL and mission capabilities of diffractive sailcraft. One of the outcomes of the incubator meeting was to focus this Phase I research on a solar polar orbiter mission for heliophysics experiments. NASA decadal surveys and other reports have repeatedly pointed out that scientists have only a paucity of information about the sun beyond the ecliptic plane. The TRL has been advanced from 1 to 3 during this Phase I research with the help of experiments that have verified the predicted force and mechanical control afforded by diffractive sails. Knowledge gained from the experiments and numerical models was not only disseminated in peer reviewed publications and conferences, but it also resulted in a patent disclosure.
The field of heterogeneous photocatalysis has grown considerably in the decades since Fujishima and Honda's ground-breaking publications of photoelectrochemistry on TiO2. Numerous review articles continue to point to both progress made in the use of heterogeneous materials (such as TiO2) to perform photoconversion processes, and the many opportunities and challenges in heterogeneous photocatalysis research such as solar energy conversion and environmental remediation. The past decade has also seen an increase in the use of molecular-level approaches applied to model single crystal surfaces in an effort to obtain new insights into photocatalytic phenomena. In particular, scanning probe techniques (SPM) have enabled researchers to take a ‘nanoscale’ approach to photocatalysis that includes interrogation of the reactivities of specific sites and adsorbates on a model photocatalyst surface. The rutile TiO2(110) surface has become the prototypical oxide single crystal surface for fundamental studies of many interfacial phenomena. In particular, TiO2(110) has become an excellent model surface for probing photochemical and photocatalytic reactions at the molecular level. A variety of experimental approaches have emerged as being ideally suited for studying photochemical reactions on TiO2(110), including desorption-oriented approaches and electronic spectroscopies, but perhaps the most promising techniques for evaluating site-specific properties are those of SPM. In this review, we highlight the growing use of SPM techniques in providing molecular-level insights into surface photochemistry on the model photocatalyst surface of rutile TiO2(110). Our objective is to both illustrate the unique knowledge that scanning probe techniques have already provided the field of photocatalysis, and also to motivate a new generation of effort into the use of such approaches to obtain new insights into the molecular level details of photochemical events occurring at interfaces. Discussion will start with an examination of how scanning probe techniques are being used to characterize the TiO2(110) surface in ways that are relevant to photocatalysis. We will then discuss specific classes of photochemical reaction on TiO2(110) for which SPM has proven indispensible in providing unique molecular-level insights, and conclude with discussion of future areas in which SPM studies may prove valuable to photocatalysis on TiO2. This work was supported by the US Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. I.L. was partially supported by a Pacific Northwest National Laboratory (PNNL) Chemical Imaging Initiative project. PNNL is a multiprogram national laboratory operated for DOE by Battelle.