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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 955 records · Page 53
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

DNA Repair Biomarkers Predict Response to Neoadjuvant Chemoradiotherapy in Esophageal Cancer

Purpose: The addition of neoadjuvant chemoradiotherapy prior to surgical resection for esophageal cancer has improved clinical outcomes in some trials. Pathologic complete response (pCR) following neoadjuvant therapy is associated with better clinical outcome in these patients, but only 22% to 40% of patients achieve pCR. Because both chemotherapy and radiotherapy act by inducing DNA damage, we analyzed proteins selected from multiple DNA repair pathways, using quantitative immunohistochemistry coupled with a digital pathology platform, as possible biomarkers of treatment response and clinical outcome. Methods and Materials: We identified 79 patients diagnosed with esophageal cancer between October 1994 and September 2002, with biopsy tissue available, who underwent neoadjuvant chemoradiotherapy prior to surgery at the Massachusetts General Hospital and used their archived, formalin-fixed, paraffin-embedded biopsy samples to create tissue microarrays (TMA). TMA sections were stained using antibodies against proteins in various DNA repair pathways including XPF, FANCD2, PAR, MLH1, PARP1, and phosphorylated MAPKAP kinase 2 (pMK2). Stained TMA slides were evaluated using machine-based image analysis, and scoring incorporated both the intensity and the quantity of positive tumor nuclei. Biomarker scores and clinical data were assessed for correlations with clinical outcome. Results: Higher scores for MLH1 (p = 0.018) and lower scores for FANCD2 (p = 0.037) were associated with pathologic response to neoadjuvant chemoradiation on multivariable analysis. Staining of MLH1, PARP1, XPF, and PAR was associated with recurrence-free survival, and staining of PARP1 and FANCD2 was associated with overall survival on multivariable analysis. Conclusions: DNA repair proteins analyzed by immunohistochemistry may be useful as predictive markers for response to neoadjuvant chemoradiotherapy in patients with esophageal cancer. These results are hypothesis generating and need confirmation in an independent data set.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

A Randomized Phase 2 Trial of Prophylactic Manuka Honey for the Reduction of Chemoradiation Therapy–Induced Esophagitis During the Treatment of Lung Cancer: Results of NRG Oncology RTOG 1012

Purpose: Randomized trials have shown that honey is effective for the prevention of radiation-induced mucositis in head and neck cancer patients. Because there is no efficacious preventative for radiation esophagitis in lung cancer patients, this trial compared liquid honey, honey lozenges, and standard supportive care for radiation esophagitis. Methods: The patients were stratified by percentage of esophagus receiving specific radiation dose (V60 Gy esophagus <30% or ≥30%) and were then randomized between supportive care, 10 mL of liquid manuka honey 4 times a day, and 2 lozenges (10 mL of dehydrated manuka honey) 4 times a day during concurrent chemotherapy and radiation therapy. The primary endpoint was patient-reported pain on swallowing, with the use of an 11-point (0-10) scale at 4 weeks (Numerical Rating Pain Scale, NRPS). The study was designed to detect a 15% relative reduction of change in NRPS score. The secondary endpoints were trend of pain over time, opioid use, clinically graded and patient-reported adverse events, weight loss, dysphagia, nutritional status, and quality of life. Results: 53 patients were randomized to supportive care, 54 were randomized to liquid honey, and 56 were randomized to lozenge honey. There was no significant difference in the primary endpoint of change in the NRPS at 4 weeks between arms. There were no differences in any of the secondary endpoints except for opioid use at 4 weeks during treatment between the supportive care and liquid honey arms, which was found to be significant (P=.03), with more patients on the supportive care arm taking opioids. Conclusion: Honey as prescribed within this protocol was not superior to best supportive care in preventing radiation esophagitis. Further testing of other types of honey and research into the mechanisms of action are needed.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

A steady state thermal duct model derived by fin-theory approach and applied on an unglazed solar collector

This paper presents the thermal modelling of an unglazed solar collector (USC) flat panel, with the aim of producing a detailed yet swift thermal steady-state model. The model is analytical, one-dimensional (1D) and derived by a fin-theory approach. It represents the thermal performance of an arbitrary duct with applied boundary conditions equal to those of a flat panel collector. The derived model is meant to be used for efficient optimisation and design of USC flat panels (or similar applications), as well as detailed thermal analysis of temperature fields and heat transfer distributions/variations at steady-state conditions; without requiring a large amount of computational power and time. Detailed surface temperatures are necessary features for durability studies of the surface coating, hence the effect of coating degradation on USC and system performance. The model accuracy and proficiency has been benchmarked against a detailed three-dimensional Finite Difference Model (3D FDM) and two simpler 1D analytical models. Results from the benchmarking test show that the fin-theory model has excellent capabilities of calculating energy performances and fluid temperature profiles, as well as detailed material temperature fields and heat transfer distributions/variations (at steady-state conditions), while still being suitable for component analysis in junction to system simulations as the model is analytical. The accuracy of the model is high in comparison to the 3D FDM (the prime benchmark), as long as the fin-theory assumption prevails (no 'or negligible' temperature gradient in the fin perpendicularly to the fin length). Comparison with the other models also shows that when the USC duct material has a high thermal conductivity, the cross-sectional material temperature adopts an isothermal state (for the assessed USC duct geometry), which makes the 1D isothermal model valid. When the USC duct material has a low thermal conductivity, the heat transfer course of events adopts a 1D heat flow that reassembles the conditions of the 1D simple model (for the assessed USC duct geometry); 1D heat flow through the top and bottom fins/sheets as the duct wall reassembles a state of adiabatic condition. (author)

14 SOLAR ENERGY↗
DOE OSTI2011

A prototype photovoltaic/thermal system integrated with transpired collector

Building-integrated photovoltaic/thermal (BIPV/T) systems may be utilized to produce useful heat while simultaneously generating electricity from the same building envelope surface. A well known highly efficient collector is the open-loop unglazed transpired collector (UTC) which consists of dark porous cladding through which outdoor air is drawn and heated by absorbed solar radiation. Commercially available photovoltaic systems typically produce electricity with efficiencies up to about 18%. Thus, it is beneficial to obtain much of the normally wasted heat from the systems, possibly by combining UTC with photovoltaics. Combination of BIPV/T and UTC systems for building facades is considered in this paper - specifically, the design of a prototype facade-integrated photovoltaic/thermal system with transpired collector (BIPV/T). A full scale prototype is constructed with 70% of UTC area covered with PV modules specially designed to enhance heat recovery and compared to a UTC of the same area under outdoor sunny conditions with low wind. The orientation of the corrugations in the UTC is horizontal and the black-framed modules are attached so as to facilitate flow into the UTC plenum. While the overall combined thermal efficiency of the UTC is higher than that of the BIPV/T system, the value of the generated energy - assuming that electricity is at least four times more valuable than heat - is between 7% and 17% higher. Also, the electricity is always useful while the heat is usually utilized only in the heating season. The BIPV/T concept is applied to a full scale office building demonstration project in Montreal, Canada. The ratio of photovoltaic area coverage of the UTC may be selected based on the fresh air heating needs of the building, the value of the electricity generated and the available building surfaces. (author)

14 SOLAR ENERGY↗
DOE OSTI2011

Analyzing the effect of the longwave emissivity and solar reflectance of building envelopes on energy-saving in buildings in various climates

A dynamic computer simulation is carried out in the climates of 35 cities distributed around the world. The variation of the annual air-conditioning energy loads due to changes in the longwave emissivity and the solar reflectance of the building envelopes is studied to find the most appropriate exterior building finishes in various climates (including a tropical climate, a subtropical climate, a mountain plateau climate, a frigid-temperate climate and a temperate climate). Both the longwave emissivity and the solar reflectance are set from 0.1 to 0.9 with an interval of 0.1 in the simulation. The annual air-conditioning energy loads trends of each city are listed in a chart. The results show that both the longwave emissivity and the solar reflectance of building envelopes play significant roles in energy-saving for buildings. In tropical climates, the optical parameters of the building exterior surface affect the building energy-saving most significantly. In the mountain plateau climates and the subarctic climates, the impacts on energy-saving in buildings due to changes in the longwave emissivity and the solar reflectance are still considerable, but in the temperate continental climates and the temperate maritime climates, only limited effects are seen. (author)

14 SOLAR ENERGY↗
DOE OSTI2016

Preparation of fine powdered composite for latent heat storage

Application of latent heat storage building envelope systems using phase-change materials represents an attractive method of storing thermal energy and has the advantages of high-energy storage density and the isothermal nature of the storage process. This study deals with a preparation of a new type of powdered phase change composite material for thermal energy storage. The idea of a composite is based upon the impregnation of a natural silicate material by a reasonably priced commercially produced pure phase change material and forming the homogenous composite powdered structure. For the preparation of the composite, vacuum impregnation method is used. The particle size distribution accessed by the laser diffraction apparatus proves that incorporation of the organic phase change material into the structure of inorganic siliceous pozzolana does not lead to the clustering of the particles. The compatibility of the prepared composite is characterized by the Fourier transformation infrared analysis (FTIR). Performed DSC analysis shows potential of the developed composite for thermal energy storage that can be easily incorporated into the cement-based matrix of building materials. Based on the obtained results, application of the developed phase change composite can be considered with a great promise.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Measuring the Hydrodynamic Linear Response of a Unitary Fermi Gas

In this work, we directly observe the hydrodynamic linear response of a unitary Fermi gas confined in a box potential and subject to a spatially periodic optical potential that is translated into the cloud at speeds ranging from subsonic to supersonic. We show that the time-dependent change of the density profile is sensitive to the thermal conductivity, which controls the relaxation rate of the temperature gradients and hence the responses arising from adiabatic and isothermal compression.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2019

A Model for Joint Probabilistic Forecast of Solar Photovoltaic Power and Outdoor Temperature

In this paper, a stochastic model is proposed for a joint statistical description of solar photovoltaic (PV) power and outdoor temperature. The underlying correlation emerges from solar irradiance that is responsible in part for both the variability in solar PV power and temperature. The proposed model can be used to capture the uncertainty in solar PV power and its correlation with the electric power consumption of thermostatically controlled loads. First, a model for solar PV power that explicitly incorporates the stochasticity due to clouds via a regime-switching process between the three classes of sunny , overcast and partly cloudy is proposed. Then, the relationship between temperature and solar power is postulated using a second-order Volterra model. This joint modeling is leveraged to develop a joint probabilistic forecasting method for solar PV power and temperature. Real-world datasets that include solar PV power and temperature measurements in California are analyzed and the effectiveness of the joint model in providing probabilistic forecasts is verified. The proposed forecasting methodology outperforms several reference methods thus portraying that the underlying correlation between temperature and solar PV power is well defined and only requires a simple lower-complexity sampling space.

14 SOLAR ENERGY↗
DOE OSTI2010

Practical Integration Approach and Whole Building Energy Simulation of Three Energy Efficient Building Technologies: Preprint

Three technologies that have potential to save energy and improve sustainability of buildings are dedicated outdoor air systems, radiant heating and cooling systems and tighter building envelopes. To investigate the energy savings potential of these three technologies, whole building energy simulations were performed for a barracks facility and an administration facility in 15 U.S. climate zonesand 16 international locations.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2010

New American Home 2011, Orlando, Florida (Brochure)

This brochure details the New American Home 2011, which demonstrates the use of innovative building materials, cutting-edge design, and the latest construction techniques.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2010

Russia’s R&D for Low Energy Buildings: Insights for Cooperation with Russia

Russian buildings, Russian buildings sector energy consumption. Russian government has made R&D investment a priority again. The government and private sector both invest in a range of building energy technologies. In particular, heating, ventilation and air conditioning, district heating, building envelope, and lighting have active technology research projects and programs in Russia.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2011

NREL Develops Diagnostic Test Cases to Improve Building Energy Simulation Programs (Fact Sheet)

This technical highlight describes NREL research to develop a set of diagnostic test cases for building energy simulations in order to achieve more accurate energy use and savings predictions. The National Renewable Energy Laboratory (NREL) Residential and Commercial Buildings research groups developed a set of diagnostic test cases for building energy simulations. Eight test cases were developed to test surface conduction heat transfer algorithms of building envelopes in building energy simulation programs. These algorithms are used to predict energy flow through external opaque surfaces such as walls, ceilings, and floors. The test cases consist of analytical and vetted numerical heat transfer solutions that have been available for decades, which increases confidence in test results. NREL researchers adapted these solutions for comparisons with building energy simulation results. Testing the new cases with EnergyPlus identified issues with the conduction finite difference (CondFD) heat transfer algorithm in versions 5 and 6. NREL researchers resolved these issues for EnergyPlus version 7. The new test cases will help users and developers of EnergyPlus and other building energy tools to identify and fix problems associated with solid conduction heat transfer algorithms of building envelopes and their boundary conditions. In the long term, improvements to software algorithms will result in more accurate energy use and savings predictions. NREL researchers plan to document the set of test cases and make them available for future consideration by validation standards such as ASHRAE Standard 140: Standard Method of Test for the Evaluation of Building Energy Analysis Computer Programs. EnergyPlus users will also have access to the improved CondFD model in version 7 after its next scheduled release.

14 SOLAR ENERGY↗
DOE OSTI2012

Solar Ready: An Overview of Implementation Practices

This report explores three mechanisms for encouraging solar ready building design and construction: solar ready legislation, certification programs for solar ready design and construction, and stakeholder education. These methods are not mutually exclusive, and all, if implemented well, could contribute to more solar ready construction.

14 SOLAR ENERGY↗
DOE OSTI2012

Electrical and Thermal Finite Element Modeling of Arc Faults in Photovoltaic Bypass Diodes

Arc faults in photovoltaic (PV) modules have caused multiple rooftop fires. The arc generates a high-temperature plasma that ignites surrounding materials and subsequently spreads the fire to the building structure. While there are many possible locations in PV systems and PV modules where arcs could initiate, bypass diodes have been suspected of triggering arc faults in some modules. In order to understand the electrical and thermal phenomena associated with these events, a finite element model of a busbar and diode was created. Thermoelectrical simulations found Joule and internal diode heating from normal operation would not normally cause bypass diode or solder failures. However, if corrosion increased the contact resistance in the solder connection between the busbar and the diode leads, enough voltage potentially would be established to arc across micron-scale electrode gaps. Lastly, an analytical arc radiation model based on observed data was employed to predicted polymer ignition times. The model predicted polymer materials in the adjacent area of the diode and junction box ignite in less than 0.1 seconds.

14 SOLAR ENERGY↗
DOE OSTI2012

Managing the Drivers of Air Flow and Water Vapor Transport in Existing Single Family Homes (Revised)

This document focuses on managing the driving forces which move air and moisture across the building envelope. While other previously published Measure Guidelines focus on elimination of air pathways, the ultimate goal of this Measure Guideline is to manage drivers which cause air flow and water vapor transport across the building envelope (and also within the home), control air infiltration,keep relative humidity (RH) within acceptable limits, avoid combustion safety problems, improve occupant comfort, and reduce house energy use.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2012

SunShot Prize: America's Most Affordable Rooftop Solar: A Competition To Spur Low-Cost Rooftop Solar Installations Across The Nation (Fact Sheet)

The SunShot Prize encourages novel public-private partnerships, original business models, and innovative approaches to installing clean, renewable solar energy. The sustainable business strategies developed by participants will provide transferable lessons that can be applied nationwide to hasten America's transition to affordable clean energy in a post-subsidy market.

14 SOLAR ENERGY↗
DOE OSTI2012

Laboratory Testing of Aerosol for Enclosure Air Sealing

Space conditioning energy use can be significantly reduced by addressing uncontrolled infiltration and exfiltration through the envelope of a building. A process for improving the air tightness of a building envelope by sealing shell leaks with an aerosol sealing technology is presented. Both retrofit and new construction applications are possible through applying this process either in attics and crawlspaces or during rough-in stage.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗