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All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Synthetic membranes and methods of use thereof

The present invention relates to synthetic membranes and use of these synthetic membranes for isolation of volatile organic compounds and purification of water. The synthetic membrane includes a hydrophobic polymer layer located on a polymeric membrane support layer. The invention includes a method of isolating volatile organic compounds with the synthetic membrane by contacting a volatile organic mixture with the hydrophobic polymer layer of the synthetic membrane and removing volatile organic compounds from the polymeric membrane support layer of the synthetic membrane by a process of pervaporation. The invention also includes a method of purifying water with the synthetic membrane by contacting an ionic solution with the hydrophobic polymer layer of the synthetic membrane and removing water from the polymeric membrane support layer of the synthetic membrane by a process of reverse osmosis. The invention also relates to methods of isolating non-polar gases by gas fractionation.

Belfort, Georges↗
DOE OSTI2022

Solution target for cyclotron production of radiometals

Methods of producing and isolating 68Ga, 89Zr, 64Cu, 63Zn, 86Y, 61Cu, 99mTc, 45Ti, 13N, 52Mn, or 44Sc and solution targets for use in the methods are disclosed. The methods of producing 68Ga, 89Zr, 64Cu, 63Zn, 86Y, 61Cu, 99mTc, 45Ti, 13N, 52Mn, or 44Sc include irradiating a closed target system with a proton beam. The system can include a solution target. The methods of producing isolated 68Ga, 89Zr, 64Cu, 63Zn, 86Y, 61Cu, 99mTc, 45Ti, 52Mn, or 44Sc further include isolating 68Ga, 89Zr, 64Cu, 63Zn, 86Y, 61Cu, 99mTc, 45Ti, 52Mn, or 44Sc by ion exchange chromatography. An example target includes a target body including a target cavity for receiving the target material; a housing defining a passageway for directing a particle beam at the target cavity; a target window for covering an opening of the target cavity; and a coolant gas flow path disposed in the passageway upstream of the target window.

DeGrado, Timothy R.↗
DOE OSTI2023

Separation, recovery and upgrading of biomass derived 2,3-butanediol

The invention relates to a two-way approach to isolate, recover and upgrade 2,3-Butanediol (2,3-BDO) from fermentation broth. A complete separation and recovery process for 2,3-BDO using acetalization and trans-acetalization sequence. Acetalization with butyraldehyde using heterogeneous catalysts, either Amberlyst-15® or Nafion NR50®, efficiently isolates 2,3-BDO as phase-separated protected dioxolane. The approach provides significant process advantages with easy product recovery and high recyclability of the catalyst. Trans-acetalization of dioxolane with methanol (methanolysis) followed by distillation of acetal, yielded very high purity 2,3-BDO with about 90% isolated yield. Alternatively, dioxolane is used in a process direct to methyl ethyl ketone (MEK) as a BDO synthon allowing for recovery of the aldehyde.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Potential for Transport of Cesium as Bio-colloids in a High Ionic Strength System

The Waste Isolation Pilot Plant (WIPP) is a deep geologic repository for long-term disposal of transuranic, radioactive waste that is a byproduct from the nation's nuclear defense program. Most likely release scenario → human intrusion (potentially through drilling) (US DOE 1995; 1996). Brine may proceed through the Rustler formation (the most transmissive layer) (Perkins et al., 1999). There is a need to investigate halophilic microbes including their mobility in the Rustler formation and the potential for enhancing transport of cesium as a bio-colloid. Objectives: To quantify the change in mobility of Cs by interaction with microbes (Chromohalobacter) that may be present near Waste Isolation Pilot Plant. What is Chromohalobacter?: a halophilic microbe, isolated from near the WIPP site, able to thrive in the high salt concentrations relevant to the repository. Does the microbe growth phase effect uptake of Cs? Experiments conducted with actively growing and stationary phase Chromohalobacter. Uptake may differ if Cs{sup +} is mistaken for K{sup +} in an actively growing (Log) phase versus stationary phase microbes (not actively reproducing). Materials: 1'' Teflon column packed with 1 gram of dolomite [355-500 μm, CaMg(CO{sub 3}){sub 2}] connected to a syringe pump and fraction collector via Teflon tubing. Chromohalobacter (100 million cells/mL) and dolomite collected near the WIPP. Synthetic brine - 15% NaCl (w/v ∼2.78 M) + 3 mM NaHCO{sub 3}. Methodology: Negative Control 5,000 ppb Cs initially injected into mini-columns with brine. Injection solution was then switched to only brine. Cs Experiments with Stationary Phase Chromo: Set 1: Viable stationary Chromo injected into minicolumns after reaction with 200 ppb Cs. Injection solution was then switched to only brine (without Cs or microbes). Set 2: Stressed stationary Chromo initially injected into mini-columns after reaction with 200 ppb Cs. Then, switched to brine only. Cs Experiments with Log phase Chromo: Set 1: Chromo injected into mini-columns after reaction with 5,000 ppb Cs. Injection then switched to only brine (without Cs or microbes). Set 2: Chromo grown with 5,000 ppb Cs and spiked with additional Cs before injection into columns. Preliminary Conclusions: Cs was not taken up or mobilized by Chromohalobacter in the actively growing or stationary phases or under stressed conditions. Competition may have occurred between Cs and K{sup +} at lower ionic strength, significantly greater concentrations of K{sup +} were present. Results suggest that Chromohalobacter can selectively uptake K{sup +} in the presence of Cs{sup +}. Future Research: K{sup +} and Cs{sup +} uptake will be monitored at high ionic strength in K{sup +} depleted media to consider uptake of Cs in the absence of K.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2024

Adaptive Laboratory Evolution for Enhanced Performance of Cupriavidus Necator on Formic Acid

The threat of global warming, driven by rising carbon emissions, highlights the need to decarbonize our economy. This requires innovative solutions for managing carbon waste and its effective utilization. One promising method for CO2 capture and sequestration is the electrochemical reduction of CO2 to formic acid, a soluble C1 molecule that can be used to store carbon and energy, and as a feedstock for biological conversion. Cupriavidus necator H16, a soil bacterium capable of consuming and growing on formic acid as its sole carbon and energy source, is well positioned to upgrade CO2-derived formic acid into platform chemicals and fuel precursors. To improve the performance of C. necator on formic acid, adaptive laboratory evolution (ALE), a proven tool for improving microbial fitness, has been conducted using continuous pH-stat bioreactors. The system works on the basis that consumption of formic acid raises the pH and triggers the addition of more formic acid to maintain the pH (in this case 6.7), such that formic acid is provided at the same rate as it is consumed. This system has been coupled with level control to achieve continuous fermentation where cells acquiring mutations that improve growth on formic acid become more abundant in the population, from which they can be isolated and characterized. During developmental experiments it was discovered that formic acid accumulated to inhibitory levels. It was determined that the nitrogen source, ammonium hydroxide, must be tailored to the carbon consumption to avoid formic acid accumulation. The ALE ran in three lineages for approximately 3000 hours and more than 500 generations. Evolved isolates obtained from each lineage demonstrated an increase in growth rate in conjunction with improve formate utilization compared to the parental strain when evaluated in pH-stat bioreactors. The isolates with improved performance were then subjected to whole genome sequencing to identify potentially causative mutations. Mutations in several key genes across different lineages have been found and will be evaluated individually and in combination to identify those that improve growth on formic acid. Incorporating these mutations into production strains has the potential to greatly improve formic acid conversion and further industrial decarbonization.

adaptive laboratory evolution↗
DOE OSTI2025

Enhancing Security and Resiliency in Operational Technology Environments Through Network Slicing and Federated Learning

The growing convergence of Information Technology (IT) and Operational Technology (OT) within Industry 4.0 environments has introduced new demands on industrial network infrastructure. As cyber-physical systems become increasingly interconnected, ensuring the secure, timely, and efficient exchange of critical data is essential. This thesis explores how network slicing, a method of creating isolated virtual network segments, can be applied within OT environments to address challenges such as latency, security, and resource allocation. The first research question addressed in this thesis is: How can OT networks take advantage of NFV and SDN technology to become cyber resilient? This study examines the operational, security, and architectural implications of introducing network slicing into traditionally static OT infrastructures such as Industrial Control Systems (ICS) and SCADA. Through simulated deployments and case studies, the research demonstrates how slicing enables better isolation between critical and non-critical services, thereby improving response time, throughput, and security in sensitive environments. The second question considers: How to dynamically implement network slicing and take advantage of network resources towards integrating decentralized machine learning? In response, this thesis proposes a framework that combines Software-Defined Networking (SDN), Network Function Virtualization (NFV), and Federated Learning (FL) to enable real-time analytics while maintaining data locality. The proposed approach reduces the burden on centralized infrastructure and minimizes privacy risks by supporting on-site training of models across distributed OT nodes, coordinated through dynamically allocated network slices. The third focus explores: How slicing helps to increase the resiliency of OT networks through the orchestration of a dynamic DMZ? To answer this, the thesis presents a method for creating and managing Dynamic Demilitarized Zones (DMZs) using network slicing. This enables flexible and automated isolation of sensitive subsystems during threat scenarios or high-risk operations. Coupled with intelligent orchestration and containerized security services, the dynamic DMZ significantly enhances the system's ability to respond to cyber incidents without halting production. Ultimately, this thesis contributes a comprehensive architecture that blends network slicing with machine learning, secure segmentation, and automation, paving the way for resilient, adaptive, and intelligent OT environments. Performance evaluations across multiple scenarios show improvements in system reliability, threat response time, model accuracy, and resource utilization, providing a strong foundation for future industrial automation systems.

Rodiles Delgado, Brian G↗
DOE OSTI2026

System-Level Efficiency Study of Modular DC/DC and Fuel Cell Stack Series–Parallel Configurations

This paper presents a system-level efficiency study of modular DC/DC converter and fuel cell stack configurations under series, parallel, and series–parallel connections. The investigation considers selected DC/DC converter topologies, including isolated and non-isolated architectures, boost, non-inverting buck-boost, and resonant converters, integrated with commercially available fuel cell stacks, including the Accelera FCE150, Ballard FCgen-HPS, and Toyota TFCM2. DC/DC converter modules are evaluated in modular configurations rated at 60 kW and 90 kW and two distinct output voltage ranges, specifically 580–730V and 780–930V, examining how different interconnection schemes impact overall system efficiency. The converters are evaluated under full load (100%), partial load (66%), and light load (33%) conditions, providing a comprehensive assessment of efficiency and operational characteristics across varying power demands. Approximately two-thousand efficiency data points are obtained from laboratory prototype–level component measurements and validated design evaluations across multiple converter topologies, modular configurations, voltage ranges, and load conditions, providing a robust dataset for comparative system-level efficiency analysis. The results highlight the effects of modularity and topology selection on system-level efficiency, offering a “playbook” framework for designers to select appropriate DC/DC converter arrangements and fuel cell stack connections for series, parallel, or hybrid configurations based on efficiency considerations.

DC/DC↗
DOE OSTI2024

Utah FORGE 1-2410: Development of a Smart Completion and Stimulation Solution - 2024 Annual Workshop Presentation

This is a presentation on the Development of a Smart Completion & Stimulation Solution by Welltec, presented by Ricardo Vasques. This video slide presentation discusses the development of an (1) annular isolation system, (2) a stimulation isolation system, and (3) a multi open-close flow system for geothermal environments. This presentation was featured in the Utah FORGE R&D Annual Workshop on August 15, 2024.

15 GEOTHERMAL ENERGY↗
DOE OSTI2023

Nonorthogonal Cascade Catalysis in Multicompartment Micelles

Multicompartment micelles (MCMs) containing acid and base sites in discrete domains are prepared from poly(norbornene)-based amphiphilic bottlebrush copolymers in aqueous media. Here, the acid and base sites are localized in different compartments of the micelle, enabling the nonorthogonal reaction sequence: deacetalization – Knoevenagel condensation – Michael addition of acetals to 2-amino chromene derivatives. Computational simulations using dissipative particle dynamics (DPD) elucidated the bottlebrush composition required to effectively site-isolate the nonorthogonal catalysts. This contribution presents MCMs as a new class of nanostructures for one-pot multistep nonorthogonal cascade catalysis, laying the groundwork for the isolation of three or more incompatible catalysts to synthesize value-added compounds in a single reaction vessel, in water.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Experimental and numerical studies of seismic fluid-structure interaction in a base-supported cylindrical vessel

Seismic design and qualification of advanced reactors will rely heavily on the use of verified and validated numerical models capable of capturing the interaction of the vessel, its contained fluid, and the internal equipment: fluid-structure interaction (FSI) analysis. Analytical solutions can be used for preliminary sizing and design of such vessels but their application is limited to simple geometries and boundary conditions, and small amplitude, translational (and rotational) inputs. To validate numerical models for seismic FSI analysis in finite element codes, a comprehensive set of experiments was performed on a liquid-filled cylindrical vessel, using a 6 degree-of-freedom earthquake simulator. Results in terms of sloshing frequency, damping ratio in sloshing modes, and hydrodynamic responses (wave height, hydrodynamic pressure, base shear, and base moment) for multi-directional earthquake simulator inputs are reported and compared with analytical solutions for liquid-filled vessels. The impact of seismic (base) isolation on hydrodynamic responses was studied using earthquake simulator inputs generated using a virtual isolation system. Data from the experiments are used to validate a numerical model of the fluid-filled vessel using the Arbitrary Lagrangian Eulerian (ALE) solver in the commercial finite element program LS-DYNA. Validation studies are presented for multi-directional seismic inputs, including rocking motions. Lagrangian modeling approaches using an elastic material formulation for the fluid are also investigated and their limitations and possible applications are identified. Here, the results are broadly applicable to the seismic response of base supported, liquid-filled vessels.

58 GEOSCIENCES↗
DOE OSTI2025

End-to-end microgrid protection using distributed data-driven methods

This paper introduces an end-to-end microgrid protection framework that offers real-time system monitoring, fault-related decision making, and circuit breaker control. This is achieved through the design of distributed data-driven techniques based on the support vector machine method, where each relay is responsible for distributed data collection, fault detection, fault localization, and fault isolation. Local communication is established among neighboring relays, fostering cooperative fault localization and isolation. This decentralized design not only reduces the computational and communication requirements but also enables the adaptability of each relay under varying operational dynamics. The proposed end-to-end protection framework was validated using MATLAB/Simulink simulations on a 100% renewable microgrid, achieving an accuracy of 93.1% with response time of 0.0523 s, in protecting against a range of fault scenarios that are characterized by various types, locations, impedances, load conditions, photovoltaic power levels, and microgrid operating modes.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2020

Leak detection in a subcritical boiler

Thermal power plants experience cycling duty leading to the fatigue of the boiler and heat exchanger tubes. As a result, tube failures occur frequently in coal fired fleets leading to forced outages. Furthermore, because the tube leaks have been the major source of unwanted shutdowns and the number of outages is increasing, present work focuses on the detection and isolation of the leak in a subcritical boiler based upon the process data from a commercial coalfired power plant. The mass balance equation around the steam drum was analyzed using timeseries data collected from a 300 MW power plant. The ratio of the feed water mass flow rate to the steam mass flow rate was defined as a key parameter for detecting leaks. The difference in slope between the feedwater and steam mass flow rate during the normal and faulty operations was established as the upper control limit for real time monitoring. To reduce false alarm rates that arise when raw signal is directly compared against the threshold due to common process fluctuations, an optimal filter was derived for smoothing. It was found that the optimal filter reacted much more quickly to process changes than an exponential moving average filter, around 8 h earlier on average. Occurrence of relatively high false alarm rates even in the filtered responses was related to the cycling of the boiler from the base load condition. Variable threshold was established to keep false alarm rates to the minimum while maintaining the leak detection rate. Finally, the leak was located at the economizer and this could readily be isolated by investigating the magnitude of the mass flow rates ratio and the temperature at the economizer outlet.

42 ENGINEERING↗
DOE OSTI2023

Shape-persistent phthalocyanine cages

Phthalocyanine (Pc), an electro-redox active moiety, has many attractive properties stemming from its large aromatic system and ability to act as a catalyst in electrochemical reactions, such as the CO 2 reduction reaction (CO 2 RR). However, due to the synthetic challenge related to geometric requirements and poor solubility (strong aggregation), discrete shape-persistent cages consisting of site-isolated, readily accessible Pc moieties have not been available. Here, we report the synthesis of Zn- and Ni-metallated Pc-based molecular cages via one-step dynamic spiroborate linkage formation in high yields. The ZnPc cage structure is unambiguously elucidated at the atomic level by single-crystal X-ray diffraction. Moreover, owing to the site-isolated redox-active metal centers, readily accessible intrinsic cavity, and shape-persistent backbone, the Ni-metallated Pc (NiPc) cage exhibits high catalytic efficiency, selectivity, and stability, superior to the non-caged control molecules in electrocatalytic CO 2 RR.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Diastereoselective Template Synthesis on Iron and Uranium

The addition of 2 equiv of t Bu 2 PSiMe 3 to 2,6-pyridinedicarboxaldehyde ((CHO) 2 Py) results in a rac / meso diastereomeric mixture of the PNP-chelating ligand 2,6-bis((trimethylsiloxy)(di- tert -butylphosphino)-methyl)-pyridine ( (OTMS) PNP t Bu ) ( 1 - r / m ) via addition of the P–Si bond across both of the aldehyde C–O bonds. Chelation of (OTMS) PNP t Bu to FeCl 2 results in the same diastereotopic ratio of ( (OTMS) PNP t Bu )FeCl 2 ( 2- r / m ) as the free ligand. Fractional crystallization allows for the isolation of the C 2 isomer, 2- r , and a template synthesis protocol allows for the synthesis and isolation of the C s isomer, 2- m , in good yield. Furthermore, the template synthesis protocol was also expanded to the f -block with the use of UCl 4 in order to assess the specificity of the template synthesis on a larger metal cation. This reaction performed on UCl 4 forms the meso diastereospecific uranium complex ( ( t Bu2P) ONO)UCl 2 (dtbpy), 3 - m , with observation of the rational intermediate ( (OTMS) PNO t Bu )UCl 3 (dtbpy), 4 - m , which arose from the respective formation of two- or one-equivalents of TMS–Cl and formation of the corresponding U–O bond.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Synthesis and Characterization of a Bridging Cerium(IV) Nitride Complex

Complexes featuring lanthanide–ligand multiple bonds are rare and highly reactive. They are important synthetic targets to understand 4f/5d-bonding in comparison to d-block and actinide congeners. Herein, the isolation and characterization of a bridging cerium(IV)-nitride complex: [(TriNOx)Ce(Li 2 μ-N)Ce(TriNOx)][BAr F 4 ] is reported, the first example of a molecular cerium-nitride. The compound was isolated by deprotonating a monometallic cerium(IV)-ammonia complex: [Ce IV (NH 3 )(TriNOx)][BAr F 4 ]. The average Ce=N bond length of [(TriNOx)Ce(Li 2 μ-N)Ce(TriNOx)][BAr F 4 ] was 2.117(3) Å. Vibrational studies of the 15 N-isotopomer exhibited a shift of the Ce=N=Ce asymmetric stretch from ν = 644 cm –1 to 640 cm –1 , and X-ray spectroscopic studies confirm the +4 oxidation state of cerium. Furthermore, computational analyses showed strong involvement of the cerium 4f shell in bonding with overall 16% and 11% cerium weight in the σ- and π-bonds of the Ce=N=Ce fragment, respectively.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Design of BLDC Motor Diagnostic Device Based on Surge Test for Phase to Ground Fault

BLDC motor is essential in the industrial world, especially it been used for an electric vehicle. The benefit of using BLDC motor is that it has high rate efficiency and low mechanical losses. However, to know the isolation condition of winding and increase reliability, it needs to be tested. With the implementation of surge test based fault detection device of BLDC motor, the condition of BLDC motor can be monitored and maintained according to analysis of its condition. The surge test method used because it is sensitive in detecting the initial damage in the isolation failure process on stator winding. A surge voltage is generated from the Cockroft-Walton and switching circuit with capacitors. The result is analyzed using Error Area Ratio (EAR). The test result shows that the higher the value of resistance and inductance, the smaller the frequency of the surge wave. When the BLDC motor in a parallel short circuit condition, the threshold value of the EAR test-reff has a minimum value of 5.28%, an average of 13.52%, and a maximum of 28.55%.

BLDC motor↗
DOE OSTI2020

Physico-chemical properties of lignin fractions from acid pretreated corn stover and their effects on enzymatic hydrolysis of microcrystalline cellulose

Lignin has been shown to be a recalcitrance factor in many biomass conversion studies. To better understand the effects of lignin on cellulose conversion, different lignin fractions were extracted from the same dilute acid pretreated corn stover by three sequential isolation methods, namely ethanol extraction, dioxane extraction, and enzyme purification. The physicochemical properties of each lignin fraction including molecular weight distribution, surface area, surface charge, and other structural features varied, depending on the isolation methods. All three lignin fractions had negative surface charges, and ethanol-extracted lignin carried the highest surface charges, followed by dioxane-extracted lignin and cellulase-purified residual lignin. These physicochemical properties of lignin fractions also resulted in different extent of inhibitory effects on enzymatic hydrolysis of microcrystalline cellulose (MCC). Dioxane-extracted lignin exhibited the highest inhibitory effect on glucose release from MCC, followed by the cellulase-purified residual lignin fraction and ethanol-extracted lignin. Furthermore, lignin fractions with higher contents of syringyl (S) substructure and β-O-4 aryl ether interunit linkages showed a stronger negative effect on cellulase hydrolysis of MCC.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Advanced Distributed Wind Turbine Controls Series: Part 1-Flatirons Campus Model Overview – Microgrids, Infrastructure Resilience, and Advanced Controls Launchpad (MIRACL)

Wind turbines are typically deployed to provide energy, reduce diesel-fuel consumption, reduce carbon emissions, and reduce costs for energy and fuel transportation. However, in addition to solely providing energy to the power system, wind turbines contain rotating masses and inverter-based controls that can enable various reliability and resilience services through advance controls. As part of the Microgrids, Infrastructure Resilience, and Advanced Controls Launchpad (MIRACL), it is demonstrated that advanced wind turbine controls can be employed to support higher contributions of wind, and to demonstrate ways that wind can play a role in supporting grid stability in islanded or grid-connected configurations. This paper documents models of various subsystem comprising a portion of NREL's Flatirons campus that will be used in three subsequent reports to demonstrate capabilities of advanced wind turbine controls. The series of reports will detail advanced capabilities of distributed wind turbines to provide support to isolated grids, distribution grids, and microgrids. We developed models to simulate a wind turbine (600 kW), solar PV (430 kW), battery energy storage system (1 MW/1MWh), a diesel generator (2 MW) and various types of loads (critical, dynamic). The model of the subsystems in MATLAB/Simulink are validated with available data from real-world components on NREL's Flatirons Campus. These validated models can be configured for various studies including four MIRACL use cases: 1) isolated grids, 2) microgrids, and 3) behind-the-meter, and 4) front-of-the-meter wind turbine deployments.

17 WIND ENERGY↗