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At least 199 records · Page 11

Systems Based Approaches for Thermochemical Conversion of Biomass to Bioenergy and Bioproducts

Auburn’s Center for Bioenergy and Bioproducts conducts research on production of synthesis gas for use in power generation and the production of liquid fuels. The overall goal of our gasification research is to identify optimal processes for producing clean syngas to use in production of fuels and chemicals from underutilized agricultural and forest biomass feedstocks. This project focused on construction and commissioning of a bubbling-bed fluidized-bed gasifier and subsequent shakedown of the gasification and gas cleanup system. The result of this project is a fully commissioned gasification laboratory that is conducting testing on agricultural and forest biomass. Initial tests on forest biomass have served as the foundation for follow-up studies on gasification under a more extensive range of temperatures, pressures, and oxidant conditions. The laboratory gasification system consists of a biomass storage tank capable of holding up to 6 tons of biomass; a biomass feeding system, with loss-in-weight metering system, capable of feeding biomass at pressures up to 650 psig; a bubbling-bed fluidized-bed gasification reactor capable of operating at pressures up to 650 psig and temperatures of 1500oF with biomass flowrates of 80 lb/hr and syngas production rates of 37 scfm; a warm-gas filtration system; fixed bed reactors for gas conditioning; and a final quench cooling system and activated carbon filtration system for gas conditioning prior to routing to Fischer-Tropsch reactors, or storage, or venting. This completed laboratory enables research to help develop economically feasible technologies for production of biomass-derived synthesis gases that will be used for clean, renewable power generation and for production of liquid transportation fuels. Moreover, this research program provides the infrastructure to educate the next generation of engineers and scientists needed to implement these technologies.

09 BIOMASS FUELS↗

Snowmass Computational Frontier: Topical Group Report on Quantum Computing

Quantum computing will play a pivotal role in the High Energy Physics (HEP) science program over the early parts of the 21$^{st}$ Century, both as a major expansion of our capabilities across the Computational Frontier, and in synthesis with quantum sensing and quantum networks. This report outlines how Quantum Information Science (QIS) and HEP are deeply intertwined endeavors that benefit enormously from a strong engagement together. Quantum computers do not represent a detour for HEP, rather they are set to become an integral part of our discovery toolkit. Problems ranging from simulating quantum field theories, to fully leveraging the most sensitive sensor suites for new particle searches, and even data analysis will run into limiting bottlenecks if constrained to our current computing paradigms. Easy access to quantum computers is needed to build a deeper understanding of these opportunities. In turn, HEP brings crucial expertise to the national quantum ecosystem in quantum domain knowledge, superconducting technology, cryogenic and fast microelectronics, and massive-scale project management. The role of quantum technologies across the entire economy is expected to grow rapidly over the next decade, so it is important to establish the role of HEP in the efforts surrounding QIS. Fully delivering on the promise of quantum technologies in the HEP science program requires robust support. It is important to both invest in the co-design opportunities afforded by the broader quantum computing ecosystem and leverage HEP strengths with the goal of designing quantum computers tailored to HEP science.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Support for the 4th Pan-American Congress on Plants and Bioenergy

Intellectual Merit: Following the success of the first three Pan-American Congresses on Plants and BioEnergy held biennially, the 4th congress will be held at the University of Guelph, Canada June 4-7, 2014. We aim to continue a tradition of showcasing major advances in energy crop improvement yet keep in perspective the realities of the economic drivers and pressures that govern the translation of scientific success into a commercial success. The congress is endorsed by the American Society of Plant Biologists and the Canadian Society of Plant Biologists. The program will cover a range of disciplines, including algal and plant systems for bioenergy, plant genetics and genomics, gene discovery for improvement of bioenergy production and quality, regulatory mechanisms of synthesis and degradation, strategies for 3rd generation biofuel production and the promise of synthetic biology in production of biofuels and bio-based products, cropping systems and productivity for biomass production, and mitigation of environmental impacts of bioenergy production. Broader Impacts: We are requesting support to generate stipends for domestic and permanent-resident students, post-doctorals, and pre-tenured faculty members to attend and benefit from the outstanding program. The stipends will be limited to registration and on-site lodging costs, with partial support for travel in instances of great need. So that as great a number can benefit as possible, airfare costs will be provided for only applicants with great need. ASPB has endorsed this meeting and will assist in advertising and promoting the meeting. ASPB has a long-standing commitment to increase participation and advance the careers in plant biology of women, minorities and underrepresented scientists, and they will assist us in identifying worthy candidates.

09 BIOMASS FUELS↗

The Data Mine model for accessible partnerships in data science

Abstract The Data Mine at Purdue University is a pioneering experiential learning community for undergraduate and graduate students of any background to learn data science. The first data‐intensive experience embedded in a large learning community, The Data Mine had nearly 1300 students in academic year (AY) 2022–2023 and nearly 1700 students for AY 2023–2024. The Data Mine embodies data‐infused education, research, and collaboration. Students learn Python, R, SQL, and shell‐scripting, while working on weekly projects within a high‐performance computing (HPC) cluster. In the Corporate Partners cohort, students work on teams of 5–15 students, led by a paid student team leader. Each cohort follows an Agile approach, working on data‐intensive projects provided by industry partners and mentored by company employees. Students develop professional and data skills throughout the academic year, from August through April. Many students return in subsequent years to the program, increasing their tenure with a Corporate Partner. Student teams are inherently interdisciplinary; students from 133 different majors are involved in the program, ranging from new incoming students through PhD level students. These interdisciplinary teams of students bring new perspectives to challenging problems in which data science is a key part of the solution. The interdisciplinary teams foster an environment of synthesis with ideas and solutions. Students come together with different life experiences, different levels of technical skill, but also varying ways they navigate paths to solutions because of the variety of majors represented, resulting in a more creative and robust solution than a traditional data science program. This article is categorized under: Applications of Computational Statistics > Education in Computational Statistics

Betz, Margaret A.↗

Sustainable Transportation Fuels from Coal, Natural Gas (≥ 90% C n H 2n+ 2 gases) and Biomass

This research program is focused primarily on the conversion of coal, natural gas (i.e., methane), and biomass to liquid fuels by Fischer-Tropsch synthesis (FTS), with minimum production of carbon dioxide. A complementary topic also under investigation is the development of novel processes for the production of hydrogen with very low to zero production of CO 2 . This is in response to the nation’s urgent need for a secure and environmentally friendly domestic source of liquid fuels. The carbon neutrality of biomass is beneficial in meeting this goal. Several additional novel approaches to limiting carbon dioxide emissions are also being explored.

10 SYNTHETIC FUELS↗

Fischer-Tropsch Synthesis: Cd, In and Sn Effects on a 15%Co/Al 2 O 3 Catalyst

The effects of 1% of Cd, In and Sn additives on the physicochemical properties and Fischer-Tropsch synthesis (FTS) performance of a 15% Co/Al 2 O 3 catalyst were investigated. The fresh and spent catalysts were characterized by BET, temperature programmed reduction (TPR), H 2 -chemisorption, NH 3 temperature programmed desorption (TPD), X-ray absorption near edge spectroscopy (XANES), and X ray diffraction (XRD). The catalysts were tested in a 1 L continuously stirred tank reactor (CSTR) at 220 °C, 2.2 MPa, H 2 /CO = 2.1 and 20–55% CO conversion. Addition of 1% of Cd or In enhanced the reduction degree of 15%Co/Al 2 O 3 by ~20%, while addition of 1% Sn slightly hindered it. All three additives adversely impacted Co dispersion by 22–32% by increasing apparent Co cluster size based on the H 2 -chemisorption measurements. However, the decreased Co active site density resulting from the additives did not result in a corresponding activity loss; instead, the additives decreased the activity of the Co catalysts to a much greater extent than expected, i.e., 82–93%. The additional detrimental effect on catalyst activity likely indicates that the Cd, In and Sn additives migrated to and covered active sites during reaction and/or provided an electronic effect. XANES results showed that oxides of the additives were present during the reaction, but that a fraction of metal was also likely present based on the TPR and reaction testing results. This is in contrast to typical promoters that become metallic at or below ~350 °C, such as noble metal promoters (e.g., Pt, Ru) and Group 11 promoters (e.g., Ag, Au) on Co catalysts in earlier studies. In the current work, all three additives remarkably increased CH 4 and CO 2 selectivities and decreased C 5+ selectivity, with the Sn and In additives having a greater effect. Interestingly, the Cd, In, or Sn additives were found to influence hydrogenation and isomerization activities. At a similar conversion level (i.e., in the range of 40–50%), the additives significantly increased 2-C 4 olefin content from 3.8 to 10.6% and n-C 4 paraffin from 50 to 61% accompanied by decreases in 1-C 4 olefin content from 48 to 30%. The Sn contributed the greatest impact on the secondary reactions of 1-olefins, followed by the In and Cd. NH 3 -TPD results suggest enhanced acid sites on cobalt catalysts resulting from the additives, which likely explains the change in selectivities for the different catalysts.

36 MATERIALS SCIENCE↗

At the interfaces of the hydrologic sciences: Connecting water, elements, ecosystems, and people through the major contributions of Dr. Emily Bernhardt

Here, in this paper, we describe the major contributions of Professor Emily Bernhardt to the hydrologic sciences. Dr. Bernhardt’s work addresses how carbon, nutrient, and contaminant dynamics respond to a wide range of environmental perturbations that alter hydrologic dynamics within and connectivity among ecosystems. Her research leverages intensive and extensive field sampling, experimental manipulations, macroscale data harmonization and exploration, and continental to global-scale synthesis activities to uncover key drivers and patterns of the impacts human perturbations have on water and elemental cycles. Dr. Bernhardt’s research program is defined by her ability to ask questions and use approaches that explicitly consider connectivity and interfaces in a variety of ways. Here, we highlight significant contributions from Dr. Bernhardt’s work, organized by connectivity, interfaces, and interactions among and across (1) elemental cycles, (2) ecosystems, (3) watersheds, (4) scales, and (5) disciplines. We conclude with a section on Dr. Bernhardt’s impact on the hydrologic sciences and beyond through her exceptional dedication to mentorship, engagement, and service.

58 GEOSCIENCES↗

Ultracoatings: Enabling Energy and Power Solutions in High Contact Stress Environments through next-generation Nanocoatings Final Technical Report

A review of current commercially available, industrial-grade, low friction coatings will show that interfacial contact pressures nearing 1GPa (~150ksi) inherently limit surface engineering solutions like WC, TiN, TiAlN, and so forth. Extremely hard coatings, then, are often pursued as the principle path, although they too are not without significant limitations. A majority of these compounds are inherently brittle in nature or may not pair well with their mating substrate. In either case, their durability in high contact stress environments is compromised. In parallel to thin film coatings, many conventional surface treatments do not yield an interface hard enough to withstand extreme stresses under load. New research into advanced, nanocomposite materials like (Ti, Zr)B 2 shows great promise. Bulk compacts of this compound have demonstrated an order of magnitude better wear resistance than current offerings, notably materials like tungsten carbide. At a laboratory level, the (Ti,Zr)B 2 nanocomposite material exhibited abrasive and erosive wear resistance nearly ten times better than existing mixed-phase boride systems. In ASTM abrasion and erosion testing, these new compositions exhibit wear resistance superior to other known advanced materials such as RocTec 500 and 'Borazon' cubic boron nitride. Many significant challenges exist for mass production of (Ti, Zr)B 2 , one of which is the necessary processing technology that is capable of minimizing deleterious impurity phases. Secondly, this material's performance is derived from a synergistic effect of the two materials existing as a single phase structure. While the individual constituents of TiB 2 and ZrB 2 do yield improvements to wear resistance, their singular effects are not as significant. Lastly, deposition of this material on a commercial level requires thorough knowledge of nanocomposite boride solids; the benefits associated with these innovative new materials are just being realized. Advancing this technology, called Ultracoatings, through initial development, scale up, and commercialization to a variety of markets would represent a transformative leap to surface engineering. Several application spaces were considered for immediate implementation of the Ultracoatings technology, including, but not limited to, a drive shaft for an aerospace fuel pump, engine timing components, and dry solids pump hardware for an innovative coal gasifier. The primary focus of the program was to evaluate and screen the performance of the selected (Ti, Zr)B 2 Ultracoatings composition for future development. This process included synthesis of the material for physical vapor deposition, sputtering trials and coating characterization, friction and wear testing on sample coupons, and functional hardware testing. The main project deliverables used to gage the project's adherence to its original objective were: Development of a coating/substrate pairing that exhibits wear rate of 0.1 mg/hour or lower at a 1GPa contact pressure, while achieving a maximum coating cost of $0.10/cm 2 . Demonstrate the aforementioned wear rate in both lubricated and starved lubrication conditions. Although the (Ti, Zr) B 2 coating was not tailored for low friction performance, friction and wear evaluations of the material demonstrated a coefficient of sliding friction as low as 0.09. This suggests that varying the percentage of TiB 2 present in the composite could enhance the materials performance in water-based lubricants. In the aerospace drive shaft application, functional hardware coated with (Ti, Zr)B 2 survived a variety of abuse and long-range durability tests, with contact pressures exceeding 2 GPa. For engine timing components, further work is planned to evaluate the Ultracoatings technology in direct injection and diesel engine conditions. In the final identified application space the dry solids pump hardware, discussions continue on the application of the Ultracoatings technology for those specific components. Full implementation of the technology into the targeted markets equates to a U.S.-based energy savings potential of over 100 trillion BTU per year by 2030. This exceeds the original projection of 60 TBTU/year by 2030.

(Ti,Zr) B2↗

Stable White Organic Light-emitting Diodes Enabled by New Materials with Reduced Excited State Lifetime (Final Report)

The Georgia Institute of Technology assembled a multidisciplinary team with complementary expertise in the areas of multi-level molecular simulations (Brédas), chemical synthesis and material characterization (Marder), and device physics and engineering (Kippelen). The team engaged in a two-year integrated theoretical and experimental program to develop blue-emissive layers that can yield simultaneously near 100% internal quantum efficiency (IQE) and short excited-state lifetimes to overcome the existing efficiency vs. stability tradeoff displayed by blue-emitting OLEDs and by WOLEDs, and to demonstrate stable WOLEDs that fulfill or exceed the 2020 target metrics (RDP 2016 section C.1.2) ahead of schedule. In this program, we investigated two general approaches involving the development of wide-bandgap ambipolar hosts with a low ΔEST. Ambipolar host achieved by intermolecular through-space D:A interactions and by intramolecular through-bond interactions between covalently linked D and A segments. Novel hosts were incorporated in to blue-emissive layers (EML) by combining them with suitable fluorescent guest emitters having high quantum yields of emission (Φem) to demonstrate blue-emitting OLEDs with high EQE and low roll-off. This final report describes the most important results achieved during this program

36 MATERIALS SCIENCE↗

Development of Passive HC/NOx Trap Catalysts for Low Temperature Gasoline Applications

This project aimed to develop fundamental understanding of the chemistry of NO adsorption and reaction in Pd/zeolites so as to facilitate the rational design of passive NOx adsorber catalysts. The approach adopted combined both experimental and computational methods, which together allow a deeper understanding of the governing chemistry than the use of either method alone. The workflow began with Pd/H-CHA and Pd/H-BEA catalyst synthesis and characterization, in which the Si/Al ratio and Al siting were systematically varied. This was followed by catalyst evaluation using temperature-programed adsorption/desorption methods, as well as in situ spectroscopic measurements to probe the chemistry of NO adsorption. In parallel, the adsorption of NO and other relevant species (H 2 O, CO, HCs) was studied by means of quantum chemical calculations in order to rationalize the experimental data and provide additional insights. Catalyst aging studies were also performed with the aim of elucidating the mechanism of catalyst degradation. Finally, the insights gained in this project were applied to the preparation of an optimized HC/NOx adsorber catalyst, the performance of which was studied using exhaust gas from an engine dynamometer.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

The Path to Savings: Understanding the Federal Purchase of Energy-Consuming Products

Energy efficiency has been a federal procurement policy objective since at least 1992, with the origin of the Energy Efficient Product Procurement (EEPP) program within the larger Federal Energy Management Program (FEMP). Today, the EEPP program’s mandate is based on requirements that 95% of new contract actions, task orders, and delivery orders for products and services be energy and water efficient, as laid out in Executive Order 13514 in 2009. Facilitating full compliance with EO 13514 presents a significant strategic planning challenge to the FEMP EEPP program, given the size of the federal government, the range of missions of its many agencies, the mix of management approaches for its buildings, and the diverse set of roughly 80 energy efficient products which has been established through preceding legislation and executive orders. The goal of this report is to aid the program in prioritizing its resources by providing an overview of how the purchase of energy-consuming products occurs in today’s evolving federal procurement system, as well as identify likely intervention points and compliance review mechanisms. Through a synthesis of the literature on U.S. federal sector procurement and two dozen primary interviews, the report particularly focuses on the importance of price in determining the actor(s) responsible for any given purchase of an energy-consuming product. This identification is important, as the relevant actors are trained and reviewed in different ways that the FEMP EEPP program can prioritize for targeting, based on the decision criteria such as the potential energy savings associated with the actor’s purchases or the administrative ease of the intervention.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Generalized optimization-based synthesis of membrane systems for multicomponent gas mixture separation

Synthesizing a membrane system to separate multicomponent gas mixture is challenging due to the combinatorial number of feasible configurations and the difficulties in describing the multicomponent permeators. Here we present a mixed-integer nonlinear programming (MINLP) model for synthesizing membrane systems for multicomponent gas mixture separation. The approach employs a richly connected superstructure to represent numerous potential system configurations, and different physics-based surrogate permeator models, such as countercurrent flow or crossflow, to be used in each stage. Moreover, to describe realistic systems, pressure drop equations can be included. We also present solution methods to accelerate the solution process. Through a case study of natural gas sweetening, we demonstrate that the proposed approach is able to obtain good solutions using an off-the-shelf global optimization solver. Finally, we expand the conventional membrane system synthesis problem by introducing feed variability in our model through a case study of an integrated reactor-separation system.

42 ENGINEERING↗

Programming Amphiphilic Peptoid Oligomers for Hierarchical Assembly and Inorganic Crystallization

Natural organisms make a wide variety of exquisitely complex, nano-, micro-, and macroscale structured materials in an energy-efficient and highly reproducible manner. During these processes, the information-carrying biomolecules (e.g., proteins, peptides, and carbohydrates) enable (1) hierarchical organization to assemble scaffold materials and execute high-level functions and (2) exquisite control over inorganic materials synthesis, generating biominerals whose properties are optimized for their functions. Inspired by nature, significant efforts have been devoted to developing functional materials that can rival those natural molecules by mimicking in vivo functions using engineered proteins, peptides, DNAs, sequence-defined synthetic molecules (e.g., peptoids), and other biomimetic polymers. Among them, peptoids, a new type of synthetic mimetics of peptides and proteins, have received particular attention because they combine the merits of both synthetic polymers (e.g., high chemical stability and efficient synthesis) and biomolecules (e.g., sequence programmability and biocompatibility). The lack of both chirality and hydrogen bonds in their backbone results in a highly designable peptoid-based system with reduced structural complexity and side chain-chemistry-dominated properties. Here in this Account, we present our recent efforts in this field by programming amphiphilic peptoid sequences for (1) the controlled self-assembly into different hierarchically structured nanomaterials with favorable properties and (2) manipulating inorganic (nano)crystal nucleation, growth, and assembly into superstructures. First, we designed a series of amphiphilic peptoids with controlled side chain chemistries that self-assembled into 1D highly stiff and dynamic nanotubes, 2D membrane-mimetic nanosheets, hexagonally patterned nanoribbons, and 3D nanoflowers. These crystalline nanostructures exhibited sequence-dependent properties and showed promise for different applications. The corresponding peptoid self-assembly pathways and mechanisms were also investigated by leveraging in situ atomic force microscopy studies and molecular dynamics simulations, which showed precise sequence dependency. Second, inspired by peptide- and protein-controlled formation of hierarchical inorganic nanostructures in nature, we developed peptoid-based biomimetic approaches for controlled synthesis of inorganic materials (e.g., noble metals and calcite), in which we took advantage of the substantial side chain chemistry of peptoids and investigated the relationship between the peptoid sequences and the morphology and growth kinetics of inorganic materials. For example, to overcome the challenges (e.g., complexity of protein- and peptide-folding, poor thermal and chemical stabilities) facing the area of protein- and peptide-controlled synthesis of inorganic materials, we recently reported the design of sequence-defined peptoids for controlled synthesis of highly branched plasmonic gold particles. Moreover, we developed a rule of thumb for designing peptoids that predictively enabled the morphological evolution from spherical to coral-shaped gold nanoparticles (NPs). With this Account, we hope to stimulate the research interest of chemists and materials scientists and promote the predictive synthesis of functional and robust materials through the design of sequence-defined synthetic molecules.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DFSynthesizer: Dataflow-based Synthesis of Spiking Neural Networks to Neuromorphic Hardware

Spiking Neural Networks (SNNs) are an emerging computation model that uses event-driven activation and bio-inspired learning algorithms. SNN-based machine learning programs are typically executed on tile-based neuromorphic hardware platforms, where each tile consists of a computation unit called a crossbar, which maps neurons and synapses of the program. However, synthesizing such programs on an off-the-shelf neuromorphic hardware is challenging. This is because of the inherent resource and latency limitations of the hardware, which impact both model performance, e.g., accuracy, and hardware performance, e.g., throughput. We propose DFSynthesizer, an end-to-end framework for synthesizing SNN-based machine learning programs to neuromorphic hardware. The proposed framework works in four steps. First, it analyzes a machine learning program and generates SNN workload using representative data. Second, it partitions the SNN workload and generates clusters that fit on crossbars of the target neuromorphic hardware. Third, it exploits the rich semantics of the Synchronous Dataflow Graph (SDFG) to represent a clustered SNN program, allowing for performance analysis in terms of key hardware constraints such as number of crossbars, dimension of each crossbar, buffer space on tiles, and tile communication bandwidth. Finally, it uses a novel scheduling algorithm to execute clusters on crossbars of the hardware, guaranteeing hardware performance. We evaluate DFSynthesizer with 10 commonly used machine learning programs. Our results demonstrate that DFSynthesizer provides a much tighter performance guarantee compared to current mapping approaches.

Computer Science↗

Benchmarking of manganese oxide materials with CO oxidation as catalysts for low temperature selective oxidation

Here CO oxidation behavior of different manganese oxide materials was studied as a model probe reaction to benchmark catalytic activities that could be useful for other aerobic oxidations. K-OMS-2, which showed intermediate activity [Ea = 3.0 and 6.3 kcal/mol for K-OMS-2 (made in solvent free procedure or SF) and K-OMS-2 (made via hydrothermal route or REF) respectively], were chosen for metal dopant studies using microwave assisted hydrothermal synthesis. These were further characterized using X-ray diffraction (XRD), N 2 sorption, Raman spectroscopy, scanning electron microscopy (SEM), and carbon monoxide temperature programmed reduction (CO-TPR). Additional characterization was carried out for Ni-K-OMS-2 materials using atomic absorption spectroscopy (AAS) and thermogravimetric analysis-mass spectroscopy (TGA-MS). Doping K-OMS-2 with Ni resulted in a large increase in oxygen mobility and re-adsorption, and the moderate activation energy for CO oxidation (13. kcal/mol) by Ni-K-OMS-2(SF) suggests that Ni-doped materials are good candidates for low temperature selective oxidation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Genomes of multicellular algal sisters to land plants illuminate signaling network evolution

Zygnematophyceae are the algal sisters of land plants. Here we sequenced four genomes of filamentous Zygnematophyceae, including chromosome-scale assemblies for three strains of Zygnema circumcarinatum . We inferred traits in the ancestor of Zygnematophyceae and land plants that might have ushered in the conquest of land by plants: expanded genes for signaling cascades, environmental response, and multicellular growth. Zygnematophyceae and land plants share all the major enzymes for cell wall synthesis and remodifications, and gene gains shaped this toolkit. Co-expression network analyses uncover gene cohorts that unite environmental signaling with multicellular developmental programs. Our data shed light on a molecular chassis that balances environmental response and growth modulation across more than 600 million years of streptophyte evolution.

59 BASIC BIOLOGICAL SCIENCES↗

Coupon synthesis status report

This letter report is in submission of completion of the Level 4 milestone number M4AT-23OR1101023 “Coupon synthesis status report” for the AT-23OR110102 “Beryllium Carbide as moderator for MSRs – ORNL” WBS number 2.04.11.01 within the larger Advanced Reactor Technologies program at Oak Ridge National Laboratory. This effort is an initial study of the viability of beryllium carbide as a future neutron moderator for molten salt reactors and other high temperature reactors. The research was awarded funding in September 2022 and this effort will be completed and reported on as a Level 2 milestone by the end of August 2023. This work is a collaboration between Oak Ridge National Laboratory and the University of Michigan. This report will discuss the status of this effort and planed work before the final reporting.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Final Report: Archiving Data to Support Data Synthesis of DOE Sponsored Elevated CO 2 Experiments

Over the last three decades DOE made a large investment in field-scale experiments in order to understand the role of terrestrial ecosystems in the global carbon cycle, and forecast how carbon cycling will change over the next century. The Smithsonian Environmental Research Center received one of the first awards in this program and managed two long-term studies (25 years and 10 years) with a total of approximately $10 million of support from DOE, and many more millions leveraged from the Smithsonian Institution and agencies such as NSF. The present DOE grant was based on the premise that such a large investment demands a proper synthesis effort so that the full potential of these experiments are realized through data analysis and modeling. The goal of the this grant was to archive legacy data from two major elevated carbon dioxide experiments in DOE databases, and to engage in synthesis activities using these data. Both goals were met. All datasets deemed a high priority for data synthesis and modeling were prepared for archiving and analysis. Many of these datasets were deposited in DOE’s CDIAC, while others are being held at the Oak Ridge National Lab and the Smithsonian Institution until they can be received by DOE’s new ESS-DIVE system at Berkeley Lab. Most of the effort was invested in researching and re-constituting high-quality data sets from a 30-year elevated CO 2 experiment. Using these data, the grant produced products that are already benefiting climate change science, including the publication of new coastal wetland allometry equations based on 9,771 observations, public posting of dozens of datasets, metadata and supporting codes from long-term experiments at the Global Change Research Wetland, and publication of two synthetic data papers on scrub oak forest responses to elevated CO 2 . In addition, three papers are in review or nearing submission reporting unexpected long-term patterns in ecosystem responses to elevated CO 2 and nitrogen in a coastal wetland.

54 ENVIRONMENTAL SCIENCES↗