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DOE OSTI2018

Effects of Exhaust Gas Recirculation (EGR) on Turbulent Combustion and Emissions in Advanced Gas Turbine Combustors with High-Hydrogen-Content (HHC) Fuels (Final Report)

This Final Report documents the entire four years of the Cooperative Agreement DE-FE0011822, from October 1, 2013 through September 30, 2017, that was competitively awarded under Funding Opportunity Announcement DE-FOA-0000795 in support of the U.S. Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) University Turbine Systems Research (UTSR) Program. Under the UTSR Program, DOE typically issues Funding Opportunity Announcement (FOA) solicitations every 1-2 years so that U.S. colleges/universities may propose research & development (R&D) projects in specific technical topic areas (e.g., combustion, aerodynamics/heat transfer, advanced materials) that have been identified as both scientifically and industrially relevant to the gas turbine industry. The primary objectives of this Purdue University project (in collaboration with Princeton University through a sub-award) was to develop experimental methods, kinetic models, and numerical tools to help quantify and predict the impact of exhaust gas recirculation (EGR) on NOx and CO emissions, combustion kinetics, radiation heat transfer, turbulent combustion, and combustion instabilities for natural gas and high hydrogen content (HHC) fuels by using laminar and turbulent flow reactors and gas turbine combustors operating at high temperatures and pressures. This project has obtained detailed data for improving chemical kinetic models to study EGR effects and provide insight into the effects of EGR on flame speeds and turbulent flame structure, as well as assessing the impact of EGR on emissions in a high-pressure combustion test rig. The project was divided into six primary tasks: 1) Project Management and Program Planning; 2) Flow Reactor Investigation of EGR Chemical Kinetics; 3) Combustion Bomb Investigation of EGR Effects on Flame Speed; 4) Investigation of EGR Effects on Turbulent Flame Structure in Reactor-Assisted Turbulent Slot (RATS) Burner; 5) Investigation of EGR Effects in Purdue Staged Combustion Test Rig; and 6) Development and Validation of a Large Eddy Simulation (LES) Tool for Gas Turbine Combustion and Emission Modeling using HHC Fuels. Details on the execution and results of each of these tasks are provided in the main report. To assist the reader, each task is described in a chapter-like format with its own separate listing of tables, figures, and references so that the results of each task/subtask (i.e., technical sections covering various experiments and modeling work focused on a specific area) can be quickly obtained while also getting an overall feel of the project execution. This chapter-like format also allows for acknowledgement of support from other programs relative to specific tasks. In this manner, the reader can more conveniently digest the R&D results in the various task/subtask sections that may be of most interest to the reader. In addition to this Final Report, the Purdue/Princeton team was able to publish 7 journal articles and provide 7 presentations at national scientific meetings/conferences to disseminate results. A listing of these journal articles and presentations is provided at the end of this report

03 NATURAL GAS↗

DOE OSTI2019

Activities to Establish Technical Confidence for HTGR Fuel Processing

The Savannah River National Laboratory (SRNL) and Jülicher Entsorgungsgesellschaft für Nuklearanlagen mbH (JEN) are partnering in the demonstration of a digestion technology for the processing of graphitebased nuclear fuels. The purpose of this partnership is to identify, demonstrate, and mature a technology for processing high temperature gas-cooled reactor (HTGR) fuel currently stored at the Jülich and Ahaus facilities in Germany. To enable a decision on receipt of the fuel by the U.S. Department of Energy (DOE), the technology for dispositioning the fuel must achieve an acceptable level of technical maturity, what is referred to as “technical confidence.”

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2018

EHS Health Assessment & Health Action Plan Report CY 2017

The (EHS) Health Action Plan initiative targets the key health risks identified through the 8-15-80 model by engaging employees to change their own healthcare story. (EHS) identified the most prevalent of the health risks amongst our population through Health Risk Assessment (HRA) and used that data to build Health Action Plans. Our 2017 Health Action Plans addressed inadequate sleep, increasing energy, stress, weight management, physical inactivity, hypertension, dyslipidemia, managing and preventing diabetes, managing low back pain, allergies & asthma, digestive health, tobacco use, and living well or maintaining low risk for those individuals who do not have a chronic condition to manage. These plans connect employees with our onsite registered dietitians, fitness professionals, health coaches, physical therapists and physicians as appropriate. In addition to addressing the physical aspects of health, the plans also emphasized pre/post-assessments to encourage building behavioral and emotional skills that promote health and facilitate lifestyle changes over a minimum of three months - just one risk reduction or behavior change to make an impact on their Division as well as Sandia's overall risk levels and ultimately healthcare costs.

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2018

EHS Health Assessment & Health Action Plan Report CY 2017

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2013

Extreme Expression of Cellulases in Poplar

Plant cell walls provide a vast, untapped source of sugars in the form of cellulose that can be fermented for the production of ethanol and other biofuels. However, there are several roadblocks to developing an economically viable cellulosic ethanol production process based on biochemical conversion, one of which is the cost of the enzymes required to change the cellulose to glucose. Historically, cellulase enzymes for digesting plant biomass have been produced and purified using bacteria. An alternative and potentially more economic approach is the production of the enzymes within the plant itself. The goal of this research was to verify a transgenic technology (In Plant Activation Technology – INPACT) in poplar which allows for the controlled high level accumulation of enzymes within the plant (Dugdale et al., 2013), and to assess the impact of the resulting cellulases on the efficiency of converting cellulose to fermentable sugars. INPACT is an inducible, gene amplification system which is unique in two ways. First, the INPACT gene cassette is designed so that the gene of interest is only transcribed in the presence of an initiation protein and as a result, no functional protein expression can occur without the initiation protein. Second, expression of the initiation protein is regulated by an inducible promoter such that INPACT acts as a switch to turn on high-level expression of proteins within the plant, and is particularly suited to proteins that may be toxic or hinder plant development as expression is tightly controlled by the INPACT trigger. The INPACT expression system combines the advantages of both stable and transient expression, and significantly, can be used to produce “difficult” proteins that cannot be expressed within the plant using conventional approaches.

09 BIOMASS FUELS↗

DOE OSTI2019

Engineering a therapeutic microbe for site-of-infection delivery of encapsulated antimicrobial peptides (AMPs)

Antimicrobial peptides (AMPs) are promising therapeutics against antibiotic resistant pathogens, but they are difficult to administer at the site of infection due to poor stability. To enhance the stability of AMPs for effective and specific delivery at a site of infection, this project aimed to develop components of a novel, cell-based, drug delivery platform for AMPs in which a therapeutic microbe is engineered to specifically detect a pathogen of interest and effectively release AMPs at high, local concentrations in response. We focused the majority of our project on developing a system to produce normally host-toxic AMPs in our model therapeutic microbe (Escherichia coli) in high quantities using a protein cage system called an encapsulin (Enc) nanocompartment system. We were able to successfully produce an AMP called HBCM2 (HB), which is effective in killing our model pathogen, Pseudomonas aeruginosa, in E. coli by fusing it to an engineered, non-cage forming Enc protein, which prevented its toxicity to the E. coli. This engineered Enc protein could then be digested by a specific protease (TEV protease) for release of HB when desired. In addition to the HB production system, we also constructed a preliminary engineered E. coli capable of sensing P. aeruginosa via its specific quorum-sensing molecule, producing HB peptide, and releasing it via self-lysis in response. Preliminary characterization of this system was conducted, but we hope to fully characterize the system in future studies. The overall results produced from this study demonstrate the power of synthetic biology to confer novel functions on cells for biomanufacturing and therapeutic applications.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2020

Fast growing high-yield wheat and canola for efficient nutrient recycling systems

Wheat and canola are two major rotation crops in the U.S. each offering advantageous traits for the agricultural value chain. Canola, a dicot rotation crop, generally offers high seed oil content. Wheat, a monocot rotation crop, offers more cellulose and other nutritious carbohydrates. As rotation crops, traits such as rapid growth rates, increased harvest yields, and high quality (digestibility, deconstructability) are desirable for food, biorefinery, and also nutrient recycling for crop rotation. Improvement of such traits has been the goal of numerous biotechnology efforts. However, alternative biotechnology techniques are typically constitutive and when applied to commercial crops have resulted in net negative consequences. For example, efforts to improve quality by lowering lignin biosynthesis have resulted in plants with poor structural integrity and diminished mass at maturity. With supports by SBIR programs from DOE and USDA, JBEI/LBNL and AFINGEN previously demonstrated engineered healthy switchgrass and alfalfa which grew with 20-30% more fermentable sugar release, 25% less lignin, faster growth, and more biomass yields than control plants. In this CRADA project supported by NASA STTR program, AFINGEN again collaborated with JBEI/LBNL and transferred the simple tissue-targeting technology from the demonstrated switchgrass and alfalfa to the two major rotation crops wheat and canola for efficient nutrient recycling systems.

09 BIOMASS FUELS↗

DOE OSTI2019

US-India Consortium for Development of Sustainable Advanced Lignocellulosic Biofuel Systems

This multi-institutional project had as it main objectives to develop a fully integrated platform for the production of advanced biofuels, specifically butanol, from sustainably produced switchgrass and biomass sorghum and to develop economic models that could guide the establishment of a crop to fuel value chain. The project was organized into three work packages: (1) WP1 Feedstock Development and Supply. Activities in this WP resulted in the development of improved biomass sorghum cultivars and biomass hybrids that generate high yields of biomass with limited inputs of water, fertilizer and agri-chemicals and that display less recalcitrance to enzymatic saccharification at the biorefinery; the identification of physiological responses and genes associated with sorghum’s tolerance to water logging as the basis for the development of biomass sorghums that can be cultivated on land prone to flooding; the identification of water-logging tolerant switchgrass genotypes among existing germplasm; the identification of management practices that maximize switchgrass biomass yield (fertilizer applications, harvest regimens) on commercial farms on different types of soil in Missouri. (2) WP2 Biorefinery Technologies. This WP included the development of a recombinant E. coli strain able to convert fermentable sugars derived from biomass sorghum and switchgrass to butyrate as a precursor for the advanced biofuel butanol. Butanol is toxic to most microbes, so that yields tend to be low. In contrast, butyrate can be produced in high titer and high yield by several naturally occurring bacteria, but these species are strictly anaerobic, which complicates commercial production. Our strategy involved developing a recombinant strain of E. coli able to produce high yields and high titers of butyrate. The butyrate can then be reduced to butanol via chemical conversion. In addition, a techno-economic analysis of converting sorghum and switchgrass biomass to ethanol was conducted based on data obtained at a pilot biorefinery. These data combined with small-scale butanol production data were used as the basis for a techno-economic analysis of biomass-to-butanol conversion. Furthermore, the biorefinery stillage was evaluated as a source of fertilizer or soil amendment. In contrast to the use of biochar as a soil amendment, stillage resulted in enhanced microbial activity in the soil and release of CO2. Stillage was determined to be a suitable feedstock for biogas production in an anaerobic digester. Biorefinery lignin can be blended with polymers to create novel UV-resistant materials promising for application in outer space, and as a source of organic acids for use in plastics. These applications offer opportunities to create value from the biorefinery residues. (3) WP3. This WP focused on development of economic models that can help define the most successful strategy for implementing biofuel production from bioenergy crops. Southeastern Missouri was determined to be the best location for a bio-butanol facility that processes biomass crops, due to the abundance of feedstock within a small radius of the facility. The most effective transportation method is by rail car. Feedstock availability was considered a more important driver for commercial success than the availability of a butanol market. The average cost of producing switchgrass biomass was calculated to be $65/ton assuming a biomass yield of 8 tons per hectare (the upper end of the yield in the commercial trials in WP2). Lower yields drive up costs, but improved genotypes will conversely reduce costs. Based on farmer surveys, conducting university extension activities was determined to positively influence farmers’ willingness to consider switchgrass. Other factors included experience with pasture land and forest land, and the availability of policies that provide a safety net to the farmers in case of instability in the biofuels market. This instability can be mitigated in part by ensuring adequate biomass supplies through diversification. The project supported the training of 20 graduate students and resulted in 57 peer-reviewed journal articles (with eight additional in review or in progress), eight book chapters and five patents.

09 BIOMASS FUELS↗

DOE OSTI2018

ICF Integrated Experiments Hypothesis Workshop Report

In late FY17, Integrated Experiments finalized the development of four different low gas-fill hohlraum implosion designs around CH, HDC, and Be ablators. These designs were primarily targeted towards achieving better implosion symmetry control than was exhibited in high gas-fill hohlraums, in order to minimize deleterious residual kinetic energy, while also continuing the control stability with moderate adiabats as was done with the high-foot design that came into existence in 2013. These designs built upon the exploration of low gas-fill hohlraum parameter space during the period between 2015-2016 and utilized (in some cases) the recent target fabrication advance of the smaller 5 μm diameter fill-tube. In order to capitalize on the investment made in developing these low gas-fill hohlraums, the ICF Program laid out a milestone for FY18 where we would “push” (in velocity) these platforms to the maximum power/energy delivery of NIF or until the platform breaks. By pushing these platforms in velocity we obtain scaling information about fusion performance, distinguish the strengths and weaknesses of each design as they are stressed further, and generate hypotheses that motivate further research to eventually learn how and why they fail when stressed too far. This information as it becomes available gets folded into our next generation of designs and into our predictive capability. Moreover, these velocity pushes resulted in record-setting levels of ICF performance. The workshop summarized in this document, covers the data obtained using these designs and the hypotheses generated from observing their performance cliffs. These hypotheses and the associated research ideas that were discussed are now being digested and sifted for incorporation into go forward plans.

42 ENGINEERING↗

DOE OSTI2020

The MFiX Particle-in-Cell Method (MFiX-PIC) Theory Guide

MFiX (Multiphase Flow with Interphase eXchanges) is an open-source multiphase flow solver developed at the National Energy Technology Laboratory. Within the code, users have access to a single phase or interpenetrating continua-based multiphase two-fluid model (TFM), a discrete element model (DEM), and a particle-in-cell model (PIC). TFM, DEM, and PIC can all be used to create multiphase simulations that include hydrodynamics, chemical reactions, and heat transfer.

01 COAL, LIGNITE, AND PEAT↗

DOE OSTI2020

Summary of Expedited Results from Samples Supporting Tank Closure Cesium Removal (TCCR) Batch 3

Savannah River Remediation (SRR) is currently operating the Tank Closure Cesium Removal (TCCR) process to remove 137 Cs from tank waste supernate using an ion exchange process. As part of that process, Savannah River National Laboratory (SRNL) receives and analyzes samples in support of the qualification of each batch to be processed. SRNL recently received supernate samples retrieved from Tank 10H as well as in-tank batch contact samples for characterization in support of qualifying Batch 3 for processing through the TCCR unit. SRNL received and characterized a set of dip samples collected from Tank 10H (one surface and one variable depth sample). No solids were observed in either sample and therefore the samples were combined, and a suite of analyses were performed on the composite sample. The density of the combined sample was 1.174 g/mL (0.18 %RSD), which was consistent with the measured sodium concentration of 3.54 M (0.08 %RSD). The 137Cs activity in the sample was 4.75E+07 dpm/mL (4.28 %RSD) and the total Cs concentration was calculated to be 1.54 mg/L (1.16E-05 M). The in-tank batch contact samples consist of 0.1 g of crystalline silicotitanate (CST) contained within a teabag device. Duplicate samples were submerged in Tank 10H supernate for a period of about 13 days, after which time they were retrieved and transferred to SRNL for analysis. At SRNL the CST was rinsed to remove excess salt solution and the CST was then air dried before being digested for analysis. Results of the analysis indicated a 137 Cs loading of 3.66E+10 ± 1.40E+09 dpm/g or 16.5 ± 0.63 Ci/kg CST . This value represents a bounding upper limit as it includes the addition of two sigma uncertainty from replicate analysis of the individual teabag samples as well as the addition of the small amount of 137 Cs activity measured in the rinse solutions. The above values are based on the air-dried mass of CST. Correcting to the true dry mass using a F-factor of 0.8191 results in a maximum loading of 20.2 ± 0.77 Ci/kg CST .

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2020

2020 Exascale Computing Project Annual Meeting (Executive Summary Report)

The Exascale Computing Project (ECP) delivers specific applications, software products, and outcomes on DOE computing facilities. Integration across these elements for specific hardware technologies for exascale system instantiations is fundamental to ECP success. The outcome of the ECP is the delivery of a capable exascale computing ecosystem to provide breakthrough solutions addressing our most critical challenges in scientific discovery, energy assurance, economic competitiveness, and national security. This outcome is not a matter of ensuring more powerful computing systems. The ECP is designed to create more valuable and rapid insights from a wide variety of applications (“capable”), which requires a much higher level of inherent efficacy in all methods, software tools, and ECP-enabled computing technologies to be acquired by DOE laboratories (“ecosystem”). The ECP annual meeting provides a unique opportunity for the core technical expertise in the United States focused on achieving this next plateau of computational science and computing performance to engage in direct discussions on project execution. Face-to-face gatherings in technical communities like this are common and needed for the exchange of scientific ideas and technical performance. The ECP annual meeting stands apart from other technical conferences and meetings in the computing community as it is uniquely and solely focused on the execution of the ECP and the integration of technical activities leading to the creation of the exascale computing ecosystem for the future. The direct interaction of key critical technical staff, who are leaders in their respective fields, and the resulting give-and-take between software, applications, and hardware and the technical co-design therein, is unique and essential to the effective execution of the ECP. The first annual meeting was held in Knoxville, Tennessee, January 31 – February 2, 2017 and brought together, for the first time, a diverse collection of researchers from 16 DOE national laboratories as well as university computer and computational science researchers to discuss shared problems and joint solutions for the development of a capable exascale computing ecosystem. These interactions resulted in focused technical plans and an energized community centered on advances for ECP. The second annual meeting was held in Knoxville, Tennessee, February 5–9, 2018. It included 643 individual thought leaders and performers in application development, software research and deployment, and hardware research and integrators, all of whom are part of the multifaceted, billion dollar HPC community. This meeting provided a platform to discuss and disseminate numerous examples where researchers with common goals and synergistic solutions came together for the first time to deliver tangible results. Additionally, at the 2018 meeting, ECP researchers had the opportunity to digest all US HPC vendor R&D product roadmaps pointing to exascale – not only to learn how their research can play a role, but, more importantly, to influence those roadmaps to ensure successful delivery on DOE applications that will contribute to (if not solve) problems of national interest in national security, science, energy, and health, as well as growing security threats. The third annual meeting was held in Houston, Texas, January 14–17, 2019. With a 19% increase in the number of registrations (768 people), and the change in location, the third annual meeting was considered the most impactful of the three at the time. The new website provided a better platform for the dissemination of the content, the new venue as a meeting hotel instead of a conference center facilitated interactions and discussions after event hours, and the addition of an award-winning mobile event conference app (Whova) transformed dramatically the attendee experience at the event. This fourth annual meeting was held in Houston, Texas, February 3-7, 2020. This meeting had an increase in the number of attendees for a total of 824 people registered (782 attendees) and included numerous enhancements based on feedback and lessons learned from previous meetings, some of which are listed here: Improved quality of the sessions, their material and the whole program.; Had more industry participation and addition of external collaborators from overseas.; Published the full agenda earlier to better accommodate attendance and travel plans based on schedule.; Centralized all sessions in one venue.; Provided additional hotels and room blocks for the attendees.; Improved communication with the audience (links, material, directions, notifications, etc.) to go paperless.; Enhanced side meeting scheduling, management and user experience.; Made available additional space and tables for impromptu meetings and side discussions.; Improved IT and A/V solutions for speakers. In addition, our final survey captured the following points as opportunities for improvement in future meetings: consider a different meeting location that is more pedestrian friendly, reduce talks during working meals to allow more collaboration and informal time, adapt the agenda to acknowledge attendees from different timezones, consider recording some of the tutorials and/or sessions to share broadly with the HPC community, have a larger poster room, provide additional power strips, and improve the WiFi.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2020

Analysis of Tank 38H (HTF-38-20-62, -63) and Tank 43H (HTF-43-20-60, -61) Samples for Support of the Enrichment Control and Corrosion Control Programs

SRNL analyzed samples from Tank 38H and Tank 43H to support ECP and CCP. The results indicate the concentrations of most species in the Tank 38H surface sample increased from the previous surface sample. The Tank 38H sub-surface sample shows only small changes in concentration for most major species in the solution from the previous sample. The large differences in the concentrations of major components between the Tank 38H surface and sub-surface samples indicate significant stratification of solution species within the tank. The Tank 38H surface and sub-surface samples both contained a small amount of sludge solids (<1 wt%). The Tank 43H surface and sub-surface samples are slightly more dilute than the previous samples. The Tank 43H sub-surface sample exhibits a composition more concentrated than the surface sample indicating some stratification within the tank. The Tank 38H surface and sub-surface sample both show large increases in the concentrations of uranium and plutonium likely due to the presence of sludge solids in both samples. (Note: the samples were digested and analyzed without filtration.) The total uranium concentrations of the two Tank 43H samples are similar to the previous sample results. The plutonium concentration in both Tank 43H samples appear to have decreased from the previous samples; however, the surface sample concentrations are close to the detection limit.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2019

Mercury Speciation and Quantification of Hanford 241-AP-107 Tank Waste Feed and Treated Samples

This report describes the second phase of a multi year project to adapt and develop an analytical technique for the low-level determination of total mercury (HgT), elemental mercury (Hg0), and monomethyl mercury (MeHg, hereafter referred to as methyl mercury) in Hanford tank waste. The focus of Phase II was to quantify the mercury (Hg) species total, elemental, and methyl mercury from a raw sample and treated (i.e., filtered and cesium-decontaminated) waste samples originating from Hanford waste tank 241-AP 107. The focus of Phase I work was to determine if mercury species can be preconcentrated from aqueous Hanford tank waste solution onto a solid adsorbent while simultaneously eliminating or very significantly reducing the parent radionuclide activity. This was demonstrated by developing protocols for the preparation, separation, and collection of total mercury and methyl mercury onto solid adsorbents, then measuring the adsorbents for radiological content at Pacific Northwest National Laboratory’s (PNNL’s) Radiochemical Processing Laboratory (RPL) on the Hanford Site. During Phase II, the Hanford tank waste material was preserved, separated (through distillation or digestion), then collected as either solid adsorbents or into liquid distillate form at the RPL and transferred to the PNNL Marine Sciences Laboratory (MSL) in Sequim, Washington, for analysis and quantification. Quantification of total, elemental, and methyl mercury was conducted under radiological control at the MSL using the ultra trace analytical capabilities available there.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2020

Development of Bio-Compatible Fluorescent Sensor

The development for biocompatible fluorescent sensors is used to understand the movement and fracking of wild boar at SRS. Current fracking methods for wild boar include physical tagging, camera monitoring, and foot tracks in the soil. None of these methods are highly effective in determining the path and habits of the animals as it depends on live imaging, soil consistency (lack of rain), and potentially a gps system is tagged properly. This system allows fracking using an additive digested by the animal and released in the urine that will fluoresce when excited with a particular laser. This method helps determine the actual movements of the animals and even provide a potential prediction model based on their routine. We partnered with Ft. Gordon to utilize their animal testing expertise in determining the best material and pathway for these materials to be excreted.

47 OTHER INSTRUMENTATION↗

DOE OSTI2021

A trait-based framework for linking microbial communities with carbon transformations under precipitation change

Droughts are common throughout the world. As the climate changes, droughts may become more frequent and intense. Still, scientists are uncertain about how drought will affect the natural world, particularly the bacteria, fungi, and other microbes that live in soils. These tiny life forms are crucial because they control the Earth’s flows of carbon and essential nutrients. Researchers at the University of California, Irvine, and Lawrence Berkeley National Laboratory teamed up to study how the microbiome, or collection of bacteria and fungi in the soil, deals with drought. Since 2007, the researchers have used shelters with retractable roofs to prevent nearly half of normal rainfall from reaching grass and shrub ecosystems, and their soil microbiomes, in Southern California. The study team discovered that microbes have some clever tricks up their sleeve for surviving drought. When growing on dead grass as a food source, microbes ramp up production of specialized chemicals called osmolytes that keep their cells from drying out. But microbes growing on dead shrubs face another problem. Unlike grass, shrub leaves are a lousy food source. To digest and consume shrub leaves, microbes have to exude more enzymes, which act like biochemical chef knives that chop complex leaf molecules into bite-sized pieces. Carbon is the coin of the microbial realm, earned via enzyme action or slurping up dead plant juices. Microbes growing under normal conditions on tasty dead grass have it easy: they can spend most of their carbon currency on growth. With drought, life gets harder as microbes need to pay up for osmolytes and ramp down their growth. It gets worse with shrub leaves because microbes have to multi-task among growth, enzyme secretion, and osmolyte production. When drought hits, microbes on shrub leaves forgo the osmolytes, probably because losing the carbon revenue from enzyme investment would be a deal-breaker for survival. The next question tackled by the researchers asked how the genes controlling microbial lifestyles sort out across the tree of life. Most microbiologists thought these lifestyles would correspond to rather large branches on the tree. But the study team found that in fact, very closely related microbes differ in important and interesting ways. For example, bacteria that have nearly identical housekeeping genes respond distinctively to warming, rainfall, and plant chemistry. As a result, soil microbiomes are much richer in diversity than originally thought. And studying microbial diversity in much greater detail could open up many more possibilities for how microbial life deals with changing environmental conditions. Trying to understand microbial life without the fine details of genetic diversity is like trying to stream Netflix on a dial-up connection. By looking across the landscape, the researchers revealed that microbial diversity is absolutely critical for maintaining the planet’s flows of carbon and nutrients. The study team designed a new technology—microbial cages—for transplanting intact microbiomes. With the cages, the researchers could move microbiomes to novel environments and compare their ability to cycle carbon and nutrients. In some cases, performance tailed off when microbiomes found themselves in a new environment, but in other cases, performance rivaled or even exceeded that of the resident microbiome. And even the low performers eventually caught up to the native microbiomes if given sufficient time. These findings mean that microbiomes—at least in Southern California—may be resilient to climate shifts due to a high diversity of microbial lifestyles. Coping with heat and drought may literally be in their DNA. The last piece of the research puzzle, and a “Holy Grail” for microbial ecologists, is to forecast the behavior of diverse microbiomes. To meet this challenge, the study team developed new theory and computer models. For the first time, these models account for hundreds of different microbes and how their intricate lifestyles cope with drought. The models are starting to connect the tiniest microbes with the global cycles that sustain Earth’s farms, fields, and forests. With that connection, it will be easier for society to plan for a world with more droughts and other climate disruptions.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2021

Baylor University Campus-Wide Deep Dive

In January 2020, staff members from the Engagement and Performance Operations Center (EPOC) and the Lonestar Education And Research Network (LEARN) met with researchers and staff at Baylor University for the purpose of a Campus-Wide Deep Dive into research drivers. The goal of this meeting was to help characterize the requirements for five campus research use cases and to enable cyberinfrastructure support staff to better understand the needs of the researchers they support. Profiled scientific use cases included: - Experimental High Energy Physics (HEP) - Proton Computed Tomography (pCT) - Nutrition and Relation to Digestive Microbiome - Baylor University Core Research Facilities - Molecular Quantum-dot Cellular Automata (QCA), and Material Science of Quantum Computing - Modeling and Simulation of Low-Dimensional and Nano-Structured Materials - Computational Fluid Dynamics Material for this event included the written documentation from each of the research areas at Baylor University, documentation about the current state of technology support, and a write-up of the discussion that took place in person. The Case Studies highlighted the ongoing challenges that Baylor University has in supporting a cross-section of established and emerging research use cases. Each Case Study mentioned unique challenges which were summarized into common needs. These included: - Tradeoffs for network/software security, and usability of the resulting infrastructure. Better communication to set expectations and understand realities is required. - Computation use on campus is widespread and healthy. While no major problems were uncovered, upgrades to maintain current usage patterns and encourage growth will be required. - Storage is a critical need for enterprise use cases and research. In particular, a campus wide ‘storage architecture’ to support research use cases (e.g. instruments, data sharing) is required in the 2-5 year time window. - Instrumentation on campus is healthy and expanding. Technology must scale with this in the form of computation and storage. - Working with LEARN to upgrade network capacity (in multiples of 10G, or upgrades to 100G) will be required in the 1-3 year time frame. - Network monitoring and visibility will help to establish external science use cases. - Data sharing via portal systems is not currently a critical need, but growing in scope. EPOC can assist Baylor with options.

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2020

Development and Optimization of a Purification Process to Recover 99 Mo from Low-enriched Uranium

Supported by the DOE-NNSA Office of Material Management & Minimization (M3), a number of domestic entities are pursuing non-highly enriched uranium (non-HEU) production of 99 Mo. As the production technologies of 99Mo pivot toward low-enriched uranium (LEU) or molybdenum targets, new reaction channels and accelerators are being evaluated. Superconducting electron linear accelerators (LINACs) with high-Z converter targets can generate bremsstrahlung photons and neutron fluxes that are capable of inducing photonuclear reactions and LEU fission. A particular advantage of a LINAC is that it does not rely on HEU-fueled reactor cores (which are currently slated for LEU conversion) and can operate on an almost continuous basis. Regarding the chemical purification of 99 Mo from irradiated uranium targets under acidic digestion, there exists a procedure known as Cintichem or modifications thereof with respect to LEU (LEU Modified Cintichem process, LMC). The process relies on a number of selective precipitation steps and column chromatography to purify Mo. It is important to note that LMC prescribes the addition of stable Mo to carry 99 Mo on alpha benzoin oxime, which reduces the specific activity of 99 Mo. This is especially important for processing 99 Mo batches with lower activities (~33 Ci of 99 Mo per batch).

07 ISOTOPE AND RADIATION SOURCES↗