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TiTa2Mo crystallizes in the orthorhombic Immm space group. The structure is one-dimensional and consists of two TiTa2Mo ribbons oriented in the (1, 0, 0) direction. Ti is bonded in a linear geometry to two equivalent Ta atoms. Both Ti–Ta bond lengths are 2.37 Å. Ta is bonded in a linear geometry to one Ti and one Mo atom. The Ta–Mo bond length is 2.30 Å. Mo is bonded in a linear geometry to two equivalent Ta atoms.
Ta2ReOs is Heusler structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Ta is bonded in a body-centered cubic geometry to four equivalent Re and four equivalent Os atoms. All Ta–Re bond lengths are 2.77 Å. All Ta–Os bond lengths are 2.77 Å. Re is bonded in a body-centered cubic geometry to eight equivalent Ta atoms. Os is bonded in a body-centered cubic geometry to eight equivalent Ta atoms.
Sr3Ta is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded to eight Sr and four equivalent Ta atoms to form distorted SrSr8Ta4 cuboctahedra that share corners with twelve equivalent SrSr8Ta4 cuboctahedra, edges with eight equivalent TaSr12 cuboctahedra, edges with sixteen SrSr8Ta4 cuboctahedra, faces with four equivalent TaSr12 cuboctahedra, and faces with fourteen SrSr8Ta4 cuboctahedra. There are four shorter (3.79 Å) and four longer (3.82 Å) Sr–Sr bond lengths. All Sr–Ta bond lengths are 3.79 Å. In the second Sr site, Sr is bonded to eight equivalent Sr and four equivalent Ta atoms to form distorted SrSr8Ta4 cuboctahedra that share corners with four equivalent SrSr8Ta4 cuboctahedra, corners with eight equivalent TaSr12 cuboctahedra, edges with twenty-four SrSr8Ta4 cuboctahedra, faces with six equivalent TaSr12 cuboctahedra, and faces with twelve SrSr8Ta4 cuboctahedra. All Sr–Ta bond lengths are 3.82 Å. Ta is bonded to twelve Sr atoms to form TaSr12 cuboctahedra that share corners with four equivalent TaSr12 cuboctahedra, corners with eight equivalent SrSr8Ta4 cuboctahedra, edges with eight equivalent TaSr12 cuboctahedra, edges with sixteen equivalent SrSr8Ta4 cuboctahedra, faces with four equivalent TaSr12 cuboctahedra, and faces with fourteen SrSr8Ta4 cuboctahedra.
CsLa(TaBr3)6 crystallizes in the trigonal P-31c space group. The structure is three-dimensional. Cs is bonded in a 12-coordinate geometry to twelve Br atoms. There are six shorter (4.09 Å) and six longer (4.24 Å) Cs–Br bond lengths. La is bonded in an octahedral geometry to six equivalent Br atoms. All La–Br bond lengths are 3.00 Å. Ta is bonded in a 5-coordinate geometry to five Br atoms. There are a spread of Ta–Br bond distances ranging from 2.61–2.96 Å. There are three inequivalent Br sites. In the first Br site, Br is bonded in a 2-coordinate geometry to two equivalent Ta atoms. In the second Br site, Br is bonded in a 3-coordinate geometry to one Cs, one La, and one Ta atom. In the third Br site, Br is bonded in a 3-coordinate geometry to one Cs and two equivalent Ta atoms.
Ta3Al2C crystallizes in the cubic P4_132 space group. The structure is three-dimensional. Ta is bonded in a bent 150 degrees geometry to six equivalent Al and two equivalent C atoms. There are a spread of Ta–Al bond distances ranging from 2.92–3.02 Å. Both Ta–C bond lengths are 2.22 Å. Al is bonded to nine equivalent Ta and three equivalent Al atoms to form AlTa9Al3 cuboctahedra that share corners with fifteen equivalent AlTa9Al3 cuboctahedra, edges with three equivalent CTa6 octahedra, faces with ten equivalent AlTa9Al3 cuboctahedra, and faces with four equivalent CTa6 octahedra. All Al–Al bond lengths are 2.63 Å. C is bonded to six equivalent Ta atoms to form distorted CTa6 octahedra that share corners with six equivalent CTa6 octahedra, edges with six equivalent AlTa9Al3 cuboctahedra, and faces with eight equivalent AlTa9Al3 cuboctahedra. The corner-sharing octahedral tilt angles are 24°.
Mg149Ta is Magnesium-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. there are twenty-seven inequivalent Mg sites. In the first Mg site, Mg is bonded to eleven Mg and one Ta atom to form MgMg11Ta cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with eighteen MgMg11Ta cuboctahedra, a faceface with one TaMg12 cuboctahedra, and faces with nineteen MgMg11Ta cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.08–3.24 Å. The Mg–Ta bond length is 3.10 Å. In the second Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share a cornercorner with one TaMg12 cuboctahedra, corners with seventeen MgMg11Ta cuboctahedra, edges with eighteen MgMg11Ta cuboctahedra, and faces with twenty MgMg11Ta cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.17–3.26 Å. In the third Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg11Ta cuboctahedra, edges with eighteen MgMg11Ta cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are eight shorter (3.19 Å) and two longer (3.20 Å) Mg–Mg bond lengths. In the fourth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg11Ta cuboctahedra, an edgeedge with one TaMg12 cuboctahedra, edges with seventeen MgMg12 cuboctahedra, and faces with twenty MgMg11Ta cuboctahedra. There are two shorter (3.17 Å) and four longer (3.19 Å) Mg–Mg bond lengths. In the fifth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg11Ta cuboctahedra, an edgeedge with one TaMg12 cuboctahedra, edges with seventeen MgMg12 cuboctahedra, and faces with twenty MgMg11Ta cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.18–3.20 Å. In the sixth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg11Ta cuboctahedra, edges with eighteen MgMg11Ta cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are two shorter (3.18 Å) and six longer (3.19 Å) Mg–Mg bond lengths. In the seventh Mg site, Mg is bonded to eleven Mg and one Ta atom to form distorted MgMg11Ta cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with eighteen MgMg11Ta cuboctahedra, a faceface with one TaMg12 cuboctahedra, and faces with nineteen MgMg11Ta cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.11–3.25 Å. The Mg–Ta bond length is 3.09 Å. In the eighth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with eighteen MgMg11Ta cuboctahedra, a faceface with one TaMg12 cuboctahedra, and faces with nineteen MgMg11Ta cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.18–3.20 Å. In the ninth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with eighteen MgMg11Ta cuboctahedra, and faces with twenty MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.19 Å. In the tenth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, an edgeedge with one TaMg12 cuboctahedra, edges with seventeen MgMg12 cuboctahedra, and faces with twenty MgMg11Ta cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.17–3.20 Å. In the eleventh Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.19 Å. In the twelfth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with eighteen MgMg11Ta cuboctahedra, and faces with twenty MgMg11Ta cuboctahedra. There are three shorter (3.18 Å) and two longer (3.19 Å) Mg–Mg bond lengths. In the thirteenth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with eighteen MgMg11Ta cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are two shorter (3.18 Å) and three longer (3.19 Å) Mg–Mg bond lengths. In the fourteenth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share a cornercorner with one TaMg12 cuboctahedra, corners with seventeen MgMg11Ta cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.17–3.21 Å. In the fifteenth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg11Ta cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.18–3.20 Å. In the sixteenth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are four shorter (3.19 Å) and three longer (3.20 Å) Mg–Mg bond lengths. In the seventeenth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg11Ta cuboctahedra, edges with eighteen MgMg12 cuboctahedra, a faceface with one TaMg12 cuboctahedra, and faces with nineteen MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.18 Å. In the eighteenth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg11Ta cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are two shorter (3.18 Å) and one longer (3.19 Å) Mg–Mg bond lengths. In the nineteenth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg11Ta cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are one shorter (3.18 Å) and four longer (3.19 Å) Mg–Mg bond lengths. In the twentieth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are four shorter (3.19 Å) and one longer (3.20 Å) Mg–Mg bond lengths. In the twenty-first Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are four shorter (3.18 Å) and two longer (3.19 Å) Mg–Mg bond lengths. In the twenty-second Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are two shorter (3.18 Å) and two longer (3.19 Å) Mg–Mg bond lengths. In the twenty-third Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.17–3.19 Å. In the twenty-fourth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are two shorter (3.19 Å) and one longer (3.20 Å) Mg–Mg bond lengths. In the twenty-fifth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. In the twenty-sixth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.20 Å. In the twenty-seventh Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. Ta is bonded to twelve Mg atoms to form TaMg12 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg11Ta cuboctahedra.
Microstructural optimization to achieve greater mechanical strength has been one of the focuses in ferritic–martensitic steels development. However, these optimized microstructures’ effects on the radiation response are not well known. In this work, two ferritic–martensitic steels (9Cr-NbMo and 9Cr-Ta) underwent neutron irradiation in the High Flux Isotope Reactor, and their room-temperature post-irradiation tensile properties and microstructure evolutions were investigated and compared. These two steels exhibit similar pre-irradiation tensile behavior, and their yield strengths are higher than that of other ferritic–martensitic steels by about 200–250 MPa. Microstructural characterization on pre-irradiated materials reveals a smaller grain size in 9Cr-Ta (2.8 ± 0.3 μm in 9Cr-Ta versus 4.3 ± 0.5 μm in 9Cr-NbMo) but higher dislocation density and precipitate density in 9Cr-NbMo. As is common for ferritic–martensitic steels at low irradiation temperatures (less than about 0.45T m ), irradiation-induced hardening at 400 °C was observed for both alloys. Irradiation at 490 °C causes the two alloys to exhibit different tensile behavior: 9Cr-Ta softens by 208 MPa in yield stress, whereas 9Cr-NbMo maintains strength. Additionally, microstructural characterizations were performed, including precipitate growth, dislocation, and defect formation. Using the barrier hardening model for microstructure–property correlation, the softening in irradiated 9Cr-Ta is primarily attributed to the significant dislocation recovery, while the strength lost from the slight dislocation recovery in 9Cr-NbMo was compensated by the additional strength from the irradiation-induced cavities. The microstructure effect (primarily precipitate, dislocation and boundary) on the radiation response is discussed herein.
Here, we report a method for promoting electrochemical stability in garnet Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 solid-state electrolyte based on a composite two-phase oxide–oxide microstructure. Grain boundary precipitation of the controlled distribution of amorphous zirconium oxide microparticles is achieved through the addition of reactive tantalum carbide. During ambient-atmosphere sintering, the carbide decomposes through an in situ reaction, the ‘extra’ Ta substituting for Zr within the Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 lattice. Density functional theory (DFT) calculations identify a thermodynamically favourable reaction path and show how substituting Ta 5+ at Zr 4+ sites affects the crystal structure as well as bulk ionic and electronic conductivities. Quantitative stereology highlights that zirconia also acts as a sintering aid, reducing compact porosity. Cryogenic focused-ion-beam scanning electron microscopy and fractography analysis of cycled solid-state electrolytes illustrates that near-universally observed intergranular Li-metal dendrite propagation is suppressed by the two-phase microstructure, favouring transgranular dendrites instead. Importantly, DFT demonstrates that compared with the Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 surface, the zirconium oxide surface per se is less electronically conductive and does not trap excess electrons to reduce Li ions. This is a key reason for the substantial improvement in the electrochemical properties over the single-phase baseline.
Semiconductor quantum dots (QDs) are well known to give rise to a quantum confined structure of excitons. Because of this quantum confinement, new physics of hot exciton relaxation dynamics arises. Decades of work using transient absorption (TA) spectroscopy have yielded initial simple observations, such as estimates of the cooling rate from single pump photon energy experiments. More detailed TA experiments employed variable pump photon energies to measure excitonic state-resolved transition rates. These TA measurements, usually the simplest form, have been employed to characterize QDs and their relaxation dynamics to this day. Yet, these TA measurements are fundamentally lacking in their ability to measure energy-resolved hot exciton cooling, which requires observation of the full cooling history through the real excitonic manifold. Here, we employ coherent multi-dimensional spectroscopy (CMDS) to perform an atomistically directed study of hot exciton cooling in CdSe QDs, revealing energy resolved relaxation dynamics. CMDS experiments are compared with simulations and prior TA measurements and simpler theories. Our findings reveal a hot exciton relaxation dynamics landscape. This relaxation dynamics landscape is a linear or sub-linear function of excess energy for different structures of QDs, with a strong size dependence. Our model simulations parameterized by the empirical pseudopotential model reproduces the experimental functional form and the dependence upon QD diameter and shell.
Mutations of polycystin-1 (PC1) are the major cause (85% of cases) of autosomal dominant polycystic kidney disease (ADPKD), which is the fourth leading cause of kidney failure. PC1 is thought to function as an atypical G protein-coupled receptor, yet the mechanism by which PC1 regulates G-protein signaling remains poorly understood. A significant portion of ADPKD mutations of PC1 encode a protein with defects in maturation or reduced function that may be amenable to functional rescue. In this work, we have combined complementary biochemical and cellular assay experiments and accelerated molecular simulations, which revealed an allosteric transduction pathway in activation of the PC1 C-terminal fragment. Our findings will facilitate future rational drug design efforts targeting the PC1 signaling function. Polycystin-1 (PC1) is an important unusual G protein-coupled receptor (GPCR) with 11 transmembrane domains, and its mutations account for 85% of cases of autosomal dominant polycystic kidney disease (ADPKD). PC1 shares multiple characteristics with Adhesion GPCRs. These include a GPCR proteolysis site that autocatalytically divides these proteins into extracellular, N-terminal, and membrane-embedded, C-terminal fragments (CTF), and a tethered agonist (TA) within the N-terminal stalk of the CTF that is suggested to activate signaling. However, the mechanism by which a TA can activate PC1 is not known. Here, we have combined functional cellular signaling experiments of PC1 CTF expression constructs encoding wild type, stalkless, and three different ADPKD stalk variants with all-atom Gaussian accelerated molecular dynamics (GaMD) simulations to investigate TA-mediated signaling activation. Correlations of residue motions and free-energy profiles calculated from the GaMD simulations correlated with the differential signaling abilities of wild type and stalk variants of PC1 CTF. They suggested an allosteric mechanism involving residue interactions connecting the stalk, Tetragonal Opening for Polycystins (TOP) domain, and putative pore loop in TA-mediated activation of PC1 CTF. Key interacting residues such as N3074–S3585 and R3848–E4078 predicted from the GaMD simulations were validated by mutagenesis experiments. Together, these complementary analyses have provided insights into a TA-mediated activation mechanism of PC1 CTF signaling, which will be important for future rational drug design targeting PC1.
Abstract Removal of neutral hydrogen atoms in the plasma edge reduces the number of charge exchange events and thus, the net energy losses in the plasma, significantly improving performance of fusion devices. Effective control of the residual pressure of hydrogen isotopes (HIs) in the plasma edge may be achieved by utilizing a hydrogen absorbing first wall interface capable of withstanding the harsh fusion environment. In this study, we have investigated tantalum (Ta) coating deposited by cold spray technology on 316L stainless steel substrate as a potential plasma-facing material surface. High fluence low energy deuterium plasma irradiation experiments and subsequent thermal annealing cycles associated with thermal desorption spectrometry (TDS) demonstrated superior structural stability of the Ta coating. TDS experiments revealed the outgassing of deuterium (as measure of its retention) for cold spray Ta coatings to be three times higher than bulk Ta and two orders of magnitude greater than bulk polycrystalline W. X-ray photoelectron spectroscopy revealed evolution of oxidation states upon deuterium irradiation and a partial recovery of the metallic signature of Ta after the thermal treatment at 1100 K.
Several current searches for physics beyond the standard model are based on measuring the electron-capture (EC) decay of radionuclides implanted into cryogenic high-resolution sensors. The sensitivity of these experiments has already reached the level where systematic effects related to atomic state energy changes from the host material are a limiting factor. One example is a neutrino mass study based on the nuclear EC decay of 7 Be to 7 Li inside cryogenic Ta-based sensors. Here, to understand the material effects at the required level, we use density-functional theory to model the electronic structure of lithium atoms in different atomic environments of the polycrystalline Ta absorber film. The calculations reveal that the Li 1s binding energies can vary by more than 2 eV due to insertion at different lattice sites, at grain boundaries, in disordered Ta, and in the vicinity of various impurities. However, the total range of Li 1s shifts does not exceed 4 eV, even for extreme amorphous disorder. Furthermore, when investigating the effects on the Li 2s levels, we find broadening of more than 5 eV due to hybridization with the Ta band structure. Material effects are shown to contribute significantly to peak broadening in Ta-based sensors that are used to search for physics beyond the standard model in the EC decay of 7 Be, but they do not explain the full extent of observed broadening. Understanding these in-medium effects will be required for current- and future-generation experiments that observe low-energy radiation from the EC decay of implanted isotopes to evaluate potential limitations on the measurement sensitivity.
The National Nuclear Security Administration (NNSA), a semi-autonomous agency within the U.S. Department of Energy (DOE), is proposing to take action at Los Alamos National Laboratory (LANL) near a wetland at Technical Area (TA) 48 and under a wetland at TA-55. The project proposes to install two 12-inch water lines along an alignment from TA-48 to Pecos Road on the east side of TA-55 (Figure 1). The proposed water lines will replace aging cast iron pipes that provide water for fire suppression to buildings within TA-55, and potable water to other areas in the Pajarito Corridor. NNSA has prepared this wetland assessment in accordance with 10 Code of Federal Regulations (CFR) Part 1022 Compliance with Wetland and Wetland Environmental Review Requirements (10 CFR Part 1022) (CFR 2003) which was promulgated to implement DOE requirements under Executive Order 11988 Wetland Management (EO 1977). A wetland is defined in 10 CFR 1022 as “the lowlands adjoining inland and coastal waters and relatively flat areas and flood prone areas of offshore islands,” and a base wetland as “the 100-year wetland, that is, a wetland with a 1.0 percent chance of flooding in any given year (CFR 2003).” This wetland assessment evaluates potential impacts to wetland values and functions from implementation of the proposed action, identifies alternatives to the Proposed Action, and allows for meaningful public comment.
The International Criticality Safety Benchmark Evaluation Project (ICSBEP) evaluation of the Godiva IV critical assembly, HEU-MET-FAST-086: GODIVA-IV DELAYED-CRITICAL EXPERIMENTS (HMF-086), was completed by Russ Mosteller. Five critical experiment configurations performed at the Los Alamos National Laboratory (LANL) Technical Area (TA)-18 were evaluated as acceptable benchmark cases. The five cases consist of four delayed critical configurations which differ in control rod positions and one prompt critical configuration. All cases calculated a lower $k_{eff}$ than measured by experiment. This data is referred to as the TA-18 Godiva IV benchmark in this report. In 2005, Godiva IV was disassembled for relocation to the Nevada Test Site (NTS), now Nevada National Security Site (NNSS), at the National Criticality Experiments Research Center (NCERC). Following the disassembly and subsequent reassembly and startup of Godiva IV at NCERC, additional information about the Godiva IV components was obtained. An errata note was added to the HMF-086 evaluation in the ICSBEP handbook to provide this new information until a revision to the benchmark evaluation could be performed. In addition to those corrections, there are differences between the Godiva IV assembly at TA-18 and the Godiva IV assembly at NCERC. These differences include both assembly-specific differences (differences in the safety block gap, differences in the control rod positions, a new NCERC Top Hat and contamination shield) as well as environmental differences, such as the size and shape of the experimental building where the assembly is located. An additional model with similar cases, referred to as the NCERC Godiva IV benchmark in this report, will be added to the revised HMF-086 to capture these additional differences. This will provide the best benchmark model of Godiva for use by those performing experiments at NCERC. The IER 555 CED-2 report documents the information that will be updated in the HMF-086 revision, both the corrections to the TA-18 Godiva IV benchmark and the subsequent changes to create a NCERC Godiva IV benchmark. It describes the measurements that will be performed for cases similar to those performed at TA-18. It also describes measurements that will be included in the evaluation as additional data.
Terephthalic acid (TA) is a high volume and high market commodity chemical which is a monomer used in making polyethylene terephthalate (known as PET) for beverage bottles and packaging films. The global demand for TA in 2012 was 47 million ton and it is expected to grow at a 6 percent rate to reach around 65 million ton in 2018. TA is currently made from petroleum derived p-xylene produced as a co-product during ethylene production in the naphtha cracking process. At present, ethylene is mostly made by ethane cracking of cheap natural gas-shale gas, making naphtha cracking to produce p-xylene uneconomical. Combined with potential unavailability of the petroleum based p-xylene to meet market demand and the end user’s interest in sustainable PET products has created significant attention towards biomass based feed sources for the TA production. The goal of the proposed work is to develop a catalytic process from a biomass-sourced feedstock to a chemical intermediate that can serve as the basis for the economical and renewable TA production that meets market needs.
Technical assistance (TA) programs can provide organizations and communities with the information, tools, and resources needed to support their development and resilience goals. The Energy Storage for Social Equity (ES4SE) TA program sought to empower undeserved communities through co-development of energy storage pathways and solutions to address community-defined challenges and needs. Evaluating the design, implementation, and outcomes of TA programs like ES4SE is critical to understanding whether program and participant goals were accomplished and how to adjust the TA approach to better meet participant needs. This evaluation explores the experiences and perceptions of community participants in the ES4SE TA program.
The U.S. Department of Energy's Office of State and Community Energy Programs engaged the National Laboratory of the Rockies to assess the return on investment (ROI) of technical assistance (TA) programs that support state, local, and Tribal energy planning. Although TA delivers value through capacity building, stakeholder engagement, and knowledge transfer, these benefits are often intangible and challenging to monetize. This study reviews existing ROI frameworks and synthesizes the most relevant elements into a hybrid approach tailored to energy TA programs. The proposed framework integrates monetary and non-monetary outcomes through early logic model development, baseline data collection, and the use of proxies for intangible benefits. As a case study, this paper applies this approach to the Communities Local Energy Action Program (Communities LEAP), demonstrating how ROI can inform program design, data strategy, and performance assessment. Findings underscore that ROI should be applied selectively and planned from the outset to ensure data alignment and attribution accuracy. The framework offers TA practitioners a structured approach that can be leveraged for future programs to evaluate and communicate the multifaceted value of TA investments.
Across the United States, every home, business, industry, and government depends on abundant, reliable, and affordable electricity. Energy stakeholders have many options to improve how energy is generated, distributed, and used, but choosing the right path can be complex and challenging. To support more informed decision-making about local electricity systems, the U.S. Department of Energy (DOE) and its national laboratories provide customized technical assistance (TA) through several different programs. These TA programs are designed to support a wide range of stakeholders with a variety of needs. Technical assistance may include brief consultations with subject-matter experts, in-depth technical modeling and analysis, stakeholder engagement, and peer-to-peer exchange. Delivering effective TA is an iterative process that requires evaluation and adaptation. A comprehensive and robust evaluation framework provides the structure needed to ensure that TA programs and practitioners remain effective, responsive to industry trends, and aligned with local needs. This toolkit provides a framework—including a clear, structured process—that TA program staff can adapt to their program's goals to evaluate success.