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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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DOE OSTI2017

A review of predictive nonlinear theories for multiscale modeling of heterogeneous materials

Since the beginning of the industrial age, material performance and design have been in the midst of innovation of many disruptive technologies. Today's electronics, space, medical, transportation, and other industries are enriched by development, design and deployment of composite, heterogeneous and multifunctional materials. As a result, materials innovation is now considerably outpaced by other aspects from component design to product cycle. In this article, we review predictive nonlinear theories for multiscale modeling of heterogeneous materials. Deeper attention is given to multiscale modeling in space and to computational homogenization in addressing challenging materials science questions. Moreover, we discuss a state-of-the-art platform in predictive image-based, multiscale modeling with co-designed simulations and experiments that executes on the world's largest supercomputers. Such a modeling framework consists of experimental tools, computational methods, and digital data strategies. Once fully completed, this collaborative and interdisciplinary framework can be the basis of Virtual Materials Testing standards and aids in the development of new material formulations. Moreover, it will decrease the time to market of innovative products.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2017

Modeling of Environmental-Economic Indicators of Regional Development

One of the current topical problems is the prediction of climate change and mitigation of its consequences. All-sided analysis of ecological, economic, and social aspects of climate issues relies on interdisciplinary assessment models. This article adapts the MERGE optimization model to the current state of the world economy and introduces into the model a new component that implements a simplified procedure of “green” GDP calculation (“green” GDP, or GGDP, provides information about the efficiency of use of environmental resources). The objective of our numerical simulations is to tests the consequences of Russia’s hypothetical participation in the program for reducing greenhouse gas (GHG) emissions and to analyze the environmental indicators of Russia’s GDP. The input data are mainly provided by the project of scenario conditions and main macroeconomic parameters for the forecasting of socio-economic development in Russia in the near future implemented by the Ministry of Economic Development of the Russian Federation. The calculations reveal the existence of reserves for Russia’s “painless” participation in environment-preserving initiatives that call for not exceeding the 1990 emission level in 2020–2025. At the same time, increasing the environmental efficiency of Russia’s GDP is a relevant task that requires immediate attention.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2019

Nuclear Crisis Communication in an Era of Fake News and Media Overload - 19414

Over the past several decades, the nuclear industry has worked diligently to improve the security and safety aspects of their technology, but it has failed to meet the challenge of the public's negative perception. Studies have shown that nuclear energy and nuclear waste evoke fear among the general populace because people see risks as immediate, unknown, uncontrollable, and potentially catastrophic. To some extent, negative public perception challenges for the nuclear industry are primarily a consequence of its own inability to communicate the benefits of nuclear science effectively with the lay public. While effective and trustworthy communication cannot guarantee success, it helps shape public opinion, and for a routinely misperceived project like a nuclear facility, that is paramount. Fukushima was the first nuclear accident to occur in the world where citizens have access to 24/7 news channels and the ability to respond in a real-time manner through social media outlets. Following the Fukushima accident, social media sites were filled with information regarding nuclear energy that were based more on mass rumor and even paranoia than facts. More locally, we have seen this trend following what was a minor external radiation release event at the WIPP in February 14, 2014. Many online news sources were flooded with anti-nuke stories aimed at pushing a fear of radiation, such as inferring an increase in cancer rates among the public from this minor incident; which was exactly the opposite of what was true. Today, when the public gets its news from social media and online sources, people are faced with rapidly changing and contrasting interpretations of the same story, depending on when they accessed the latest news. They are also increasingly vulnerable to fake news, including disinformation deliberately planted and cultivated by the anti-nuclear movement. Public reactions following these nuclear events reinforced the value of effective communication in maintaining the high level of transparency necessary for long-term, local acceptance and support for nuclear facilities. A lack of trustworthy communication leaves a vacuum that can be quickly filled by rumors and fake information. When dealing with a nuclear crisis, failure to recognize the rapidly changing and contrasting media framing, or believing fake news could have very real and catastrophic consequences. Trusted organizations must swiftly take charge and guide the way in which the crisis is framed to keep the public adequately and accurately informed. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Neptunium-Based High-Flux Pulsed Research Reactor

The design principles and parameters of a promising neutron source, based on the fission reaction of the isotope {sup 237}Np, for use in research in extracted beams are presented. Such a source can operate as a pulsing reactor or super-booster or as a super-booster multiplying the neutrons from the target of a proton accelerator by using a reactivity modulator. Owing to the threshold character of {sup 237}Np fission such a neutron source will possess significantly higher characteristics than a similar setup with plutonium, and in terms of utilization efficiency it will be the leading source in the world for research employing neutron spectroscopy.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2018

One-Component Spray Polyurethane Foam from Liquefied Pinewood Polyols: Pursuing Eco-Friendly Materials

The use of petroleum-derived products should be avoided regarding the principles of green and sustainable chemistry. The work reported herein, is aimed at the liquefaction of pine shavings for the production of an environmentally-friendly polyol suitable to be used in the formulations of sprayable polyurethane foams. The biopolyols were obtained in high yield and were used to replace those derived from fossil sources, to produce more “greener” polyurethane foams and therefore, less dependent on petroleum sources, since the polyol component was substituted by products resulting from biomass liquefaction. The partial and fully exchange of the polyols was accomplished, and the results compared with a reference foam. The foams were afterward, chemical, physical, morphological, and mechanically characterized. The complete replacement of polyether polyol and polyol polyester has presented some similar characteristics as that used as a reference, validating that the path chosen for the development of more sustainable materials is on the right track for the contribution to a cleaner world.

09 BIOMASS FUELS↗
DOE OSTI2019

Prospect Analysis and Hydrocarbon Reservoir Volume Estimation in an Exploration Field, Shallow Offshore Depobelt, Western Niger Delta, Nigeria

The daunting challenge in the exploration and production of oil and gas in the face of continual rise in the world’s energy consumption has long been how to economically recover bypassed reserves within existing assets. This research is focused on the analysis of prospects and volumetric estimation of the hydrocarbon reservoirs delineated within an exploratory field using 3D seismic data and suites of wireline logs. The prospectivity of the delineated reservoir was carried out using seismo-structural interpretation and formation evaluation towards the assessment of the prolific hydrocarbon occurrence within the field. The reservoirs have porosity (0.29–0.32) for H1, (0.20–0.31) for H2 and (0.30–0.40) for H3 and the average computed hydrocarbon saturation of (0.31–0.62) for H1, (0.16–0.52) for H2 and (0.64–0.73) for H3, hydrocarbon pore volume (HCPV) of 28,706.95, 33,081.2 and 45,731.49 barrels for H1, H2 and H3, respectively, while the estimated stock tank oil initially-in-place (STOIIP) range (136.8–140.73) MMSTB for H1, (36.77–489.64) MMSTB for H2 and (166.62–308.14) MMSTB for H3. The observed porosity and hydrocarbon saturation for the delineated reservoirs as well as the estimated hydrocarbon pore volume and storage total oil in place indicate that the reservoirs are highly prolific. The study has therefore contributed to the understanding of hydrocarbon resource potential within the study area.

58 GEOSCIENCES↗
DOE OSTI2019

Evaluation of Impact of Potential Extreme Rainfall Events on Mining in Peru

The impact that climate change may play in the future sustainability of mining projects has become increasingly important for the mining industry and its stakeholders. The most significant areas of concern are mine infrastructure, supply chains, health and safety conditions, environmental management, community relations and exploration. This is particularly relevant to mining in a country as climatically vulnerable as Peru. This study focuses on the identification of mining regions and main commodities in Peru that are potentially vulnerable to future extreme rainfall events associated with climate change. From a mine design and planning perspective, this study is a first step to illustrate the importance of considering the impacts of different climatic scenarios on mining in Peru. Based on HadGEM2-ES global climate model projections, mining regions across Peru were clustered into “super-regions” with differing potentials of extreme rainfall events during the next three decades. Five indices for precipitation extremes were used, and their variations between 1971–2000 and 2015–2034 were computed. Current and future metallic mining projects expected to take place across Peru in the next 30 years were retrieved from a mining database and subsequently exported into a geographical information systems software to represent their location and interpolate the variation for each precipitation extreme index. The results of this study point out at a decreasing trend in rainfall extremes intensity and frequency in regions of southern Peru. For copper projects located in these regions, a decrease in rainfall events could also imply an eventual decrease in total precipitation and consequently a deficit in water availability during the next three decades. Mining regions in central Peru, with significant number of zinc projects, are likely to experience a marked increase in overall annual precipitation, average daily precipitation intensity, consecutive days of precipitation and number of heavy precipitation days. At a lesser extent than in central Peru, gold projects in northern Peru are also likely to experience an overall increase in precipitation extremes. The approach used for this research could be extended to other mining regions around the world with extreme weather events.

58 GEOSCIENCES↗
DOE OSTI2019

Performance of Composite Insulators Used for Electric Transmission under Extreme Climatic Conditions

Composite or polymeric insulators are being used in various parts of the world for high-voltage transmission and distribution lines. In some parts of India, places in the states like Rajasthan and Gujarat experience an increase in the daytime temperature up to 50 °C, while the nighttime temperature reduces as low as 3-5 °C. Because of these extreme temperature variations along with electric stress and humidity conditions, composite insulators have to perform well over their lifetime to ensure the reliability of the transmission network. In the present work, experimental conditions are simulated with temperature variation from 50 to 3-5 °C along with electrical stress, humidity variation, pollution, and ultraviolet radiations. Accelerated aging studies with these stresses are conducted to understand the degradation on the insulator similar to the field conditions. Surface resistivity measurements, leakage current analysis, and surface degradation studies using thermogravimetric analysis, scanning electron microscopy, energy-dispersive x-ray, and Fourier transform infrared spectroscopy (FTIR) are conducted. Some interesting results obtained from the study are presented. Experimentation under extreme conditions with polluted insulators showed considerable degradation which was inferred from the material testing analysis. The insulator slabs on which electrical stress was not applied showed a considerable peak at 1500 cm{sup −1} in the FTIR spectra, indicating the generation of low molecular weight PDMS chains from the bulk due to UV aging and thermal stress, while the degradation pattern of non-polluted sample was severe compared to the slab treated but was considerably less severe in comparison with the polluted insulator sample exhibiting pollution can considerably increase degradation rate.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Land cover change-induced decline in terrestrial gross primary production over the conterminous United States from 2001 to 2016

As one of the most dynamic aspects of global environmental change, land cover change (LCC) has a profound impact on terrestrial carbon sequestration. However, LCC-induced carbon fluxes are still the most uncertain terms in global and regional carbon budgets. Ecosystem gross primary production (GPP) is the total carbon uptake by vegetation through photosynthesis, serving as a major control on ecosystem function and land carbon balance during and after the modification of the land surface. However, accurately capturing LCC-induced GPP changes requires both high-quality land cover data and controlling for variation driven by other environmental factors such as climate. In this study, we comprehensively examined the effects of LCC on annual GPP trends over the conterminous United States (CONUS) from 2001 to 2016 using the USGS National Land Cover Database, a remote sensing-driven ecosystem model, and the Google Earth Engine cloud computing platform. We designed a series of model experiments to identify LCC effects on GPP by controlling climate effects. During the study period, LCC exerted a strong negative effect on total GPP across the CONUS ([-2.2, -1.8] Tg C yr -2 ), while climate had smaller positive effects ([0.17, 0. 92] Tg C yr -2 ). The LCC-induced reduction of GPP was mainly caused by net forest loss ([-1.98, -1.39] Tg C yr -2 ) and urban expansion ([-2.03, -1.92] Tg C yr -2 ), but was partially offset by increases in crop area ([+0.66, +0.79] Tg C yr -2 ). Ensemble simulations from TRENDY did not capture the strong negative LCC influences on GPP, likely due to limitations of the adopted land use/cover data. Overall, our study provides a novel perspective on LCC-induced GPP changes, which could help to improve our understanding of ecosystem function changes and constrain the estimation of land carbon balance in the context of anthropogenic activity and climate change.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

De Broglie relations, gravitational time dilation and weak equivalence principle

Interplays between quantum physics and gravity have long inspired exciting studies, which reveal subtle connections between quantum laws and the general notion of curved spacetime. One important example is the uniqueness of free-falling motions in both quantum and gravitational physics. In this work, we re-investigate the free-falling motions of quantum test wave packets that are distributed over weakly curved spacetime backgrounds. Except for the de Broglie relations, no assumption of priori given Hamiltonians or least actions satisfied by the quantum system is made. We find that the mean motions of quantum test wave packets can be deduced naturally from the de Broglie relations with a generalized treatment of gravitational time dilations in quantum waves. Such mean motions of quantum test masses in gravitational field are independent of their masses and compositions, and restore exactly the free-falling or geodesic motions of classical test masses in curved spacetime. This suggests a novel perspective that weak equivalence principle, which states the universality of free-fall, may be deeply rooted in quantum physics and be a phenomenon that has emerged from the quantum world.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2018

Insight of nitric oxide signaling: A potential biomarker with multifaceted complex mechanism in colorectal carcinogenesis

Highlights: • Colorectal carcinogenesis (CRC) is the most important health concerns. • Several etiological factors are associated with colo-rectal carcinogenesis. • Nitric Oxide pathway (NO) is associated with tumour cells initiation, invasion and progression. Colorectal carcinogenesis (CRC) is the most important health concerns throughout the World as the tumour cells rapidly spread and abruptly grow in colon and rectum to further organs. Several etiological factors are associated with colorectal carcinogenesis. During invasion and proliferation of tumour cells, various mechanistic molecular pathways are involved in the cells. Nitric Oxide pathway (NO) is one of the important cellular mechanisms associated with tumour cells initiation, invasion and progression. Epidemiological evidences suggest that NO has potential role in development of cancer. The multidisciplinary action of NO on the initiation of cancer depends on several factors including cell type, metastasis stage, and organs involved. This review emphasizes the biological significance of NO in each step of cancer metastasis, its controversial effects for carcinogenesis including initiation, invasion and progression.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Metagenomic analysis revealed the effects of goat milk feeding and breast feeding on the gut microbiome of Amur tiger cubs

Highlights: • First time to use metagenomic analyze the effects of different milk feeding patterns on gut microbiome of Amur tiger cubs. • Goat milk feeding and breast feeding can change the composition and functional structures of gut microbiota in Amur tiger. • Breastfed Amur tiger cubs and goat milk-fed Amur tiger cubs have distinct microbiotas in their guts. Ingredients in breast milk can help establish a healthy community of microorganisms in the infant gut, but no research exists regarding the effects of goat milk feeding and breast feeding on the gut microbiome of the Amur tiger, which is one of the most endangered species in the world.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Vegetable ashes as Supplementary Cementitious Materials

Approximately 140 billion metric tons of biomass are produced every year in the world from agriculture. The ashes resulting from firing agricultural wastes such as rice husk, sugar cane and others can be used as Supplementary Cementitious Materials (SCM). They can be mixed with lime alone or in ternary mixtures with Portland cement and lime. If fired at temperatures around 600–700 °C the agricultural ashes exhibit good reactivity. Despite extensive research work carried out on the use of agricultural ashes as source of SCMs, few success stories are reported on practical applications on an industrial scale. Details of the firing technology should be re-assessed, with special emphasis on the scale at which the technology begins to be economically suitable. Further research is also needed to understand the mechanisms of structural transformation of amorphous silica during calcination, and the impact of the ashes on cement hydration in blended systems.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Assessing the urban carbon footprint: An overview

All cities present environmental sustainability issues, above all regarding greenhouse gas (GHG) emissions, and specifically carbon dioxide (CO{sub 2}), that directly affect climate change. Consequently, it is very important to quantify and report their Carbon Footprint (CF) for implementing national and international policies/strategies aimed at mitigating and adapting these concerns. The Urban Carbon Footprint (UCF), indeed, has been recognized as the more valuable choice to inform, specifically, decision makers about city environmental sustainability. Several accounting systems and inventory methods have been taken into account to perform UCF, highlighting the complexity of the topic and generating very often confusion among users. In this context, the authors aim to summarize what has been done and what is going on with UCFs, trying to classify them according to some principal dimensions. Thus, they divide UFCs in two main categories namely: “spatial” or “direct”, with a limited amount of data requested, and “economic” or “life cycle based”, more or less data inclusive according to the accounting systems considered. Furthermore, they observe that there is not a “global agreed-upon protocol” yet, neither is there a specific model shared among researchers, even if some steps have been made towards this direction (Relative Carbon Footprint - RCF, Publicly Available Specification – PAS 2070 and Global Protocol for Community scale - GPC). Consequently, it is necessary to complete and standardize, in the short term, the accounting and reporting frameworks, in order to compare different UCFs for adopting shared climate strategies and actions at global level. - Highlights: •Cities present environmental sustainability issues. •GHG emissions - specifically carbon dioxide - directly affect climate change. •UCF is a tool to support policy makers towards city environmental sustainability. •There is not a “global agreed-upon protocol” to perform UFC. •There are still missing points to be considered to provide a sharing model.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2018

The nexus between water, energy, and food in the context of the global risks: An analysis of the interactions between food, water, and energy security

The purpose of this article is to analyze the interactions between water, energy, and food security, referenced in this study as the nexus between water, energy, and food, and the impacts of global risks using the World Economic Forum's, 2017 Global Risks Report as a guideline. In this analysis, the authors reveal that water, energy, and food are interdependent and essential resources demanding sustainable, integrated and intelligent management. These vital resources are susceptible to many global risks which are maximized by extreme weather events, mass involuntary human migrations, and other hazards that predominantly endanger the vulnerable communities of less developed countries. In conclusion, policies carried out by the international community, decision-makers, civil society, and the private sector, must align to target and mitigate global risks, specifically, water, energy and food security.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2017

Cadmium, lead, and arsenic contamination in paddy soils of a mining area and their exposure effects on human HEPG2 and keratinocyte cell-lines

A mining district in south China shows significant metal(loid) contamination in paddy fields. In the soils, average Pb, Cd and As concentrations were 460.1, 11.7 and 35.1 mg kg{sup −1} respectively, which were higher than the environmental quality standard for agricultural soils in China (GB15618-1995) and UK Clea Soil Guideline Value. The average contents of Pb, Cd and As in rice were 5.24, 1.1 and 0.7 mg kg{sup −1} respectively, which were about 25, 4.5 or 2.5 times greater than the limit values of the maximum safe contaminant concentration standard in food of China (GB 2762-2012), and about 25, 10 or 1 times greater than the limit values of FAO/WHO standard. The elevated contents of Pb, Cd and As detected in soils around the factories, indicated that their spatial distribution was influenced by anthropogenic activity, while greater concentrations of Cd in rice appeared in the northwest region of the factories, indicating that the spatial distribution of heavy metals was also affected by natural factors. As human exposure around mining districts is mainly through oral intake of food and dermal contact, the effects of these metals on the viability and MT protein of HepG2 and KERTr cells were investigated. The cell viability decreased with increasing metal concentrations. Co-exposure to heavy metals (Pb+Cd) increased the metals (Pb or Cd)-mediated MT protein induction in both human HepG2 and KERTr cells. Increased levels of MT protein will lead to greater risk of carcinogenic manifestations, and it is likely that chronic exposure to metals may increase the risk to human health. Nevertheless, when co-exposure to two or more metals occur (such as As+Pb), they may have an antagonistic effect thus reducing the toxic effects of each other. Capsule: Metal contaminations in paddy soils and rice were influenced by anthropogenic activity; metal co-exposure induced MT protein in human cells. - Highlights: • Pb, Cd and As in paddy soils and rice were higher than national and FAO standards. • Pb, Cd and As spatial distribution was mainly influenced by anthropogenic activity. • The HepG2 and KERTr cell viability decreased with increasing metal concentrations. • Co-exposure to heavy metals increased MT protein induction in HepG2 and KERTr cells. • Co-exposure to some metals (As+Pb) may have an antagonistic effect.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2017

Integrated assessment of infant exposure to persistent organic pollutants and mercury via dietary intake in a central western Mediterranean site (Menorca Island)

In this research the levels of organochlorine compounds (OCs) and mercury (Hg) in several food items from Menorca Island were presented. The dietary exposure assessment was performed in children population from the island. Finally, body burden of OCs and Hg in these infants were associated with their dietary intakes of the selected food items. The dietary exposure to persistent pollutants by children population from Menorca Island was assessed. The concentrations of 11 organochlorine pesticides, 6 polychlorinated biphenils (PCBs) and 1 inorganic toxic element, Hg, were determined in 46 food samples that included fish, shellfish, meat, fruit, vegetables, cheese and eggs, which were acquired in local markets and department stores in the Menorca Island. The most contaminated food items were fish and shellfish, followed by meat and cheese products. OC levels were similar or lower than in other previous studies. However, 66% of the analysed fish and shellfish species for Hg exceeded the human consumption safety limits according to the European Union Legislation. Pollutant data from food was combined with the pattern of consumption of these foodstuffs in order to calculate the estimated daily intake (EDI) of these contaminants. According to our results, fish and fruit were the main sources of OCs to the EDIs (contributing to 37% and 29%, respectively) while fish and shellfish were the main sources of Hg (76% and 17%). The estimated EDIs of OCs were well below to the reported FAO/WHO Tolerable Intakes. However, estimated weekly intake of Hg would exceed the Provisional Tolerable Weekly Intake indicated by EFSA in the case that the only fish and seafood source would be from the central western Mediterranean. Direct associations between fish/shellfish consumption and hair concentrations of Hg and fish and meat consumption and 4,4’-DDT concentrations in venous serum in the Menorcan children were observed. - Highlights: • The levels of the organochlorine compounds in the Menorcan food items were low. • Mercury was above the EU recommendations in 66% of the analysed seafood samples. • Fish/shellfish consumption was related with the Hg levels in hair of children. • 4,4’-DDT in serum of children was related to fish and meat consumption. • The Hg weekly intake of Menorcan children exceeded more than twice the EFSA limits.

54 ENVIRONMENTAL SCIENCES↗