Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Preparations”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11

Devices and methods for performing shear-assisted extrusion, extrusion feedstocks, extrusion processes, and methods for preparing metal sheets

Devices and methods for performing shear-assisted extrusion processes for forming extrusions of a desired composition from a feedstock material are provided. The processes can use a device having a scroll face having an inner diameter portion bounded by an outer diameter portion, and a member extending from the inner diameter portion beyond a surface of the outer diameter portion.Extrusion feedstocks and extrusion processes are provided for forming extrusions of a desired composition from a feedstock. The processes can include providing a feedstock having at least two different materials and engaging the materials with one another within a feedstock container.Methods for preparing metal sheets are provided that can include preparing a metal tube via shear assisted processing and extrusion; opening the metal tube to form a sheet having a first thickness; and rolling the sheet to a second thickness that is less than the first thickness.

Whalen, Scott A.↗

Zinc oxide based sorbent and process for preparing same

Zinc oxide-based sorbents, and processes for preparing and using them are provided, wherein the sorbents are preferably used to remove one or more reduced sulfur species from gas streams. The sorbents contain an active zinc component, optionally in combination with one or more promoter components and/or one or more substantially inert components. The active zinc component is a two-phase material, consisting essentially of a zinc oxide (ZnO) phase and a zinc aluminate (ZnAl 2 O 4 ) phase. Each of the two phases is characterized by a relatively small crystallite size of typically less than about 50 nm (500 Angstroms). Preferably the sorbents are prepared by using an alkali metal base to convert a precursor mixture, containing a precipitated zinc oxide precursor and a precipitated aluminum oxide precursor, to the two-phase, active zinc oxide containing component, with the resulting sorbent having a sodium level within a desired range.

Shen, Jian-Ping↗

Systems and methods for preparing butenes

Systems for preparing butenes are provided. The systems can include a reactor inlet coupled to both a reactor and at least one reactant reservoir; at least one of the reactant reservoirs containing one or both of an aldehyde and/or ethanol; a catalyst within the reactor, the catalyst comprising a metal component and an acidic support material; and a reactor outlet operationally configured to convey a butene-rich reaction product to a product reservoir. Methods for preparing butenes are also provided. The methods can include exposing one or both of ethanol and/or an aldehyde to a catalyst comprising a metal component and an acidic support to form a butene-rich product that comprises one or both of 1-butene and/or 2-butene.

Dagle, Vanessa↗

Compositions for carbon dioxide separation using steam regeneration, and method for preparing same

Compositions and methods of preparing the compositions are disclosed for sorbents and other surfaces that can adsorb and desorb carbon dioxide. A sorbent or surface can include a metal compound such as an alkali or alkaline earth compound and a support. The sorbent can be prepared by several methods, including an incipient wetness technique. The sorbents have a CO 2 adsorption and desorption profile. A sorbent having high levels of a metal compound and adsorbed CO 2 is disclosed.

Elliott, Jeannine Elizabeth↗

Technical Issues that Need to Be Addressed in Preparing a Large Program to Transport SNF and HLW - 20093

The U.S. Nuclear Waste Technical Review Board (Board) has been interested for many years in the Department of Energy (DOE) activities related to transporting spent nuclear fuel (SNF) and high-level radioactive waste (HLW). The Board has conducted several public meetings and issued associated reports on this topic. In September 2019, the Board issued a report entitled Preparing for Nuclear Waste Transportation-Technical Issues that Need to Be Addressed in Preparing for a Nationwide Effort to Transport Spent Nuclear Fuel and High-Level Radioactive Waste [1] that focuses on the issues DOE will need to address to plan and implement an integrated transportation program. In its report, the Board describes 30 broad technical issues that DOE needs to address and offers three sets of findings and recommendations to DOE. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Expedited Walkdowns and Preparation of Cost Estimates for Decontamination and Demolition of Excess Facilities - 20335

Lawrence Livermore National Security, LLC (LLNS) is the prime contractor responsible for managing and operating Lawrence Livermore National Laboratory (LLNL). The mission of the LLNL is to strengthen security of the United States through development and application of world-class science and technology to enhance the nation's defense, reduce the global threat from terrorism and weapons of mass destruction, and respond with vision, quality, integrity, and technical excellence to scientific issues of national importance. To accomplish its mission, LLNL must plan and manage its campus space and facilities to optimize use of its relatively small one-square-mile footprint. LLNL currently has numerous excess facilities that require decontamination and demolition (D and D). The LLNL Legacy Facility Program is responsible for stewardship and risk reduction programs to effectively manage these excess assets at LLNL. The Legacy Facility Program identified 10 excess facilities at LLNL that were candidates for demolition based on risks from further degradation of the facilities, potential exposure to hazardous materials, or need for removal to make way for new program facilities. The buildings range from a structure built in 1943 to serve as a US Navy drill hall during World War II, to a facility that provided neutrons to study material properties for the fusion energy program. The National Nuclear Security Administration (NNSA) appropriated FY19 funding for the development of Class 3 estimates for these 10 excess facilities that would be used to develop a Program Management Plan for funding consideration. Class 3 estimates are not conceptual, nor overly detailed, but adequate to be used for budget and appropriation purposes. Using existing strategic sourcing agreements, LLNL was able to organize a team of senior subject matter experts (SMEs) with diverse technical backgrounds across the Department of Energy (DOE) Complex to complete extensive process knowledge (PK) reviews and walk-downs of each excess facility and to deliver accurate and complete estimates under an expedited schedule (i.e., within eight weeks). To facilitate the expedited schedule, LLNL was fully prepared for the arrival of the JGMS team, which consisted of the following companies: J.G. Management Systems, Inc. (JGMS); Strata-G, LLC; and Michael Baker International. LLNL provided background and PK information on the excess facilities, pictures, supporting historical documentation, and radiological survey history as well as escorted access to the facilities. The JGMS team has previous experience supporting Program Management Plans for excess facilities at the Y-12 National Security Complex. The team mobilized to LLNL and performed the facility walk-downs from January 22-25, 2019. Using a methodical evaluation process, expertise, and experience, the team was able to deliver walk-down draft reports and estimates to LLNL before their February 8, 2019 deadline. LLNL then in turn reviewed, completed the estimates by adding waste management costs and other LLNL costs, and delivered the estimates to NNSA by February 15, 2019. The completed final reports, including draft D and D estimates, were delivered to LLNL before their March 6, 2019 deadline. The work was successfully completed ahead of the expedited schedule required by LLNL, resulting in a commendation from the client. This paper describes how the partnership and collaboration as a fully integrated team comprised of the prime contractor, LLNS, and the JGMS team successfully met the needs of the US government, resulting in the performance of expedited site walk-downs, the development of summary evaluation reports, and the preparation of draft Class 3 estimates and preliminary schedules for the D and D of 10 excess facilities at LLNL. The efforts of the team will enable the D and D of the first excess facility in the 2020-2021 time frame. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Recognizing Institutions that Prepare Students for 21st Century Building Careers

Buildings play a significant role in reaching the White House's goal of a net-zero emissions economy by 2050, so it is critical that building professionals are prepared to design and construct high-efficiency, low-carbon buildings powered by renewables. The U.S. Department of Energy's Zero Energy Design Designation recognizes post-secondary academic programs that prepare students for 21st century building careers. ZEDD is a three-year designation, and as of 2023 almost 40 programs of study from more than 25 institutions have been recognized and supported by DOE for their great work. The University of Cincinnati received the ZEDD designation for the Net Zero Energy Design Track in Architectural Engineering Program. Tracks, majors, minors, and certificates are all eligible for ZEDD. In recent interviews with faculty from the University of Cincinnati and Appalachian State University about their experiences with ZEDD, many common topics came up. Both faculty members mentioned their students who graduate with ZEDD on their resume are often the only people in their future design firms who understand and can create net zero energy designs.

buildings↗

Surface Preparation of Additively Manufactured 316H Stainless Steel for Molten Salt Applications

Additive manufacturing (AM) has the potential to revolutionize the manufacturing process and speed up deployment of advance nuclear reactors. However, more information is needed on preparing AM materials for extreme reactor environments to qualify AM materials for nuclear applications. This project studies the surface preparation of AM 316H stainless steel using acid pickling and reports a successful procedure for descaling heat-treated AM material.

316H Stainless Steel↗

Spent-fuel recycling molecule degradation product standards can be produced with preparative liquid chromatography

Solvent systems used for spent nuclear fuel separation schemes are subject to intense radiation fields from the spent fuel, resulting in a degradation of separation performance over time from both the radiolytic destruction of active compounds (extractants, holdback agents, etc.) and the production of degradation compounds (compounds produced from the destruction of the active compounds). Development of a quantitative understanding of the effects of radiolysis on separations is impeded by a near-complete lack of availability of degradation products from chemical manufacturers. Synthesis of these degradation products through traditional means is both cost and time prohibitive, inhibiting advancement of new fuel separation processes. We hypothesize that comprehensive sets of degradation products can be synthesized using preparative radiolysis, and purified using high performance liquid chromatography in quantities sufficient for unequivocal identification and subsequent use as quantitative analytical studies. Achieving this objective will facilitate development of a much more accurate understanding of radiolysis reactions and their effects on solvent extraction processes, positioning Idaho National Laboratory (INL) in a leadership role in the science of fuel cycle separations. We propose producing these degradation compounds by irradiating concentrated samples of solvent ligands in the INL gamma irradiator, separating the resulting mixture with preparative chromatography, and removing the mobile phase in the separated fractions with a vacuum concentrator. This will yield milligram to gram quantities of purified degradation products, sufficient for fundamental research, at a fraction of the time and cost of synthesis. Facile production of separation molecule degradation products at minimal cost will enable the fundamental research that will accelerate the development of fuel cycles that will ensure the competitiveness of nuclear energy.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Aggregated nanoparticles: Sample preparation and analysis by atom probe tomography

Atom probe tomography (APT) allows measurement of the three-dimensional structure and composition of materials, but specific sample preparation procedures are required for challenging materials such as aggregates of nanoparticles. Indeed, the presence of porosity within the specimen affects both the stability of the sample and the accuracy of the data. In this work, aggregates of nanoparticles were transferred onto a micromanipulator tip and embedded via electron-beam-assisted deposition of Pt. Successive FIB-millings and Pt-depositions are needed to create suitable APT tips. The 3D reconstruction reveals the presence of 15–20 nm nanoparticles, and massspectral analysis shows the absence of trace elements within the catalyst, thus serving as quality control for the synthesis of nanoparticles with specific compositions.

77 NANOSCIENCE AND NANOTECHNOLOGY↗

Addressing quantum’s “fine print” with efficient state preparation and information extraction for quantum algorithms and geologic fracture networks

Abstract Quantum algorithms provide an exponential speedup for solving certain classes of linear systems, including those that model geologic fracture flow. However, this revolutionary gain in efficiency does not come without difficulty. Quantum algorithms require that problems satisfy not only algorithm-specific constraints, but also application-specific ones. Otherwise, the quantum advantage carefully attained through algorithmic ingenuity can be entirely negated. Previous work addressing quantum algorithms for geologic fracture flow has illustrated core algorithmic approaches while incrementally removing assumptions. This work addresses two further requirements for solving geologic fracture flow systems with quantum algorithms: efficient system state preparation and efficient information extraction. Our approach to addressing each is consistent with an overall exponential speed-up.

58 GEOSCIENCES↗

Preparing exact eigenstates of the open XXZ chain on a quantum computer

The open spin-1/2 XXZ spin chain with diagonal boundary magnetic fields is the paradigmatic example of a quantum integrable model with open boundary conditions. Here, we formulate a quantum algorithm for preparing Bethe states of this model, corresponding to real solutions of the Bethe equations. The algorithm is probabilistic, with a success probability that decreases with the number of down spins. For a Bethe state of L spins with M down spins, which contains a total of $(^{L}_{M})$ $2^{M} M!$ terms, the algorithm requires L+M 2 +2M qubits.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

State Preparation in the Heisenberg Model through Adiabatic Spiraling

An adiabatic state preparation technique, called the adiabatic spiral, is proposed for the Heisenberg model. This technique is suitable for implementation on a number of quantum simulation platforms such as Rydberg atoms, trapped ions, or superconducting qubits. Classical simulations of small systems suggest that it can be successfully implemented in the near future. A comparison to Trotterized time evolution is performed and it is shown that the adiabatic spiral is able to outperform Trotterized adiabatics.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

Carrier-assisted One-pot Sample Preparation for Targeted Proteomics Analysis of Small Numbers of Human Cells

Protein analysis of small numbers of human cells is primarily achieved by targeted proteomics with antibody-based immunoassays, which have inherent limitations (e.g., low multiplex and unavailability of antibodies for new proteins). Mass spectrometry (MS)-based targeted proteomics has emerged as an alternative because it is antibody-free, high multiplex, and has high specificity and quantitation accuracy. Recent advances in MS instrumentation make MS-based targeted proteomics possible for multiplexed quantification of highly abundant proteins in single cells. However, there is a technical challenge for effective processing of single cells with minimal sample loss for MS analysis. To address this issue, we have recently developed a convenient protein carrier-assisted one-pot sample preparation coupled with liquid chromatography (LC) - selected reaction monitoring (SRM) termed cLC-SRM for targeted proteomics analysis of small numbers of human cells. This method capitalizes on using the combined excessive exogenous protein as a carrier and low-volume one-pot processing to greatly reduce surface adsorption losses as well as high-specificity LC-SRM to effectively address the increased dynamic concentration range due to the addition of exogeneous carrier protein. Its utility has been demonstrated by accurate quantification of most moderately abundant proteins in small numbers of cells (e.g., 10-100 cells) and highly abundant proteins in single cells. The easy-to-implement features and no need for specific devices make this method readily accessible to most proteomics laboratories. In this study, we have provided a detailed protocol for cLC-SRM analysis of small numbers of human cells including cell sorting, cell lysis and digestion, LC-SRM analysis, and data analysis. Further improvements in detection sensitivity and sample throughput are needed towards targeted single-cell proteomics analysis. We anticipate that cLC-SRM will be broadly applied to biomedical research and systems biology with the potential of facilitating precision medicine.

60 APPLIED LIFE SCIENCES↗

Preparation of 2D Polyaniline/MoO 3– x Superlattice Nanosheets via Intercalation-Induced Morphological Transformation for Efficient Chemodynamic Therapy

Organic intercalation of layered nanomaterials is an attractive strategy to fabricate organic/inorganic superlattices for a wide range of promising applications. However, the synthesis of 2D organic/inorganic superlattice nanosheets remains a big challenge. In this work, the preparation of 2D polyaniline/MoO 3–x (PANI/MoO 3–x ) superlattice nanosheets via intercalation-induced morphological transformation from MoO 3 nanobelts, as efficient Fenton-like reagents for chemodynamic therapy (CDT), is reported. Micrometer-long MoO 3 nanobelts are co-intercalated with Na + /H 2 O followed by the guest exchange with aniline monomer for in situ polymerization to obtain PANI/MoO 3–x nanosheets. Intriguingly, the PANI intercalation can induce the morphological transformation from long MoO 3 nanobelts to 2D PANI/MoO 3–x nanosheets along with the partial reduction of Mo 6+ to Mo 5+ , and generation of rich oxygen vacancies. More importantly, thanks to the PANI intercalation-induced activation, the PANI/MoO 3–x nanosheets exhibit excellent Fenton-like catalytic activity for generation of hydroxyl radical (·OH) by decomposing H 2 O 2 compared with the MoO 3 nanobelts. It is speculated that the good conductivity of PANI can facilitate electron transport during the Fenton-like reaction, thereby enhancing the efficiency of CDT. Thus, the polyvinylpyrrolidone-modified PANI/MoO 3–x nanosheets can function as Fenton-like reagents for highly efficient CDT to kill cancer cells and eradicate tumors.

2D materials↗

Preparation of pH ‐responsive cellulose nanofibril/sodium alginate based hydrogels for drug release

Abstract In this work, hydrogels composed of cellulose nanofibril (CNF) and sodium alginate (SA) were prepared as a pH‐responsive release system by controlling the amount of CNF and SA. Scanning electron microscopy, thermogravimetric analysis, and swelling rate methods were used to characterize. The results showed that when the mass ratio of CNF to SA was 2:1, CNF/SA hydrogels with better morphology were obtained. Due to the deprotonation or protonation of calcium alginate, as the pH changing from 1.5 to 11.0, the swelling ratio increased from 7 times to 19 times compared with its dry weight. The drug release behaviors of the CNF/SA hydrogels using ibuprofen (IBU) as a model drug were investigated in vitro. The release of IBU was faster in alkaline conditions and slower in acidic conditions. The drug release mechanism under pH stimulation could be interpreted by the Fickian diffusion and erosion effect based on Korsmeyer‐Peppas model.

Li, Yuhang↗

Adaptive Variational Quantum Imaginary Time Evolution Approach for Ground State Preparation

Abstract An adaptive variational quantum imaginary time evolution (AVQITE) approach is introduced that yields efficient representations of ground states for interacting Hamiltonians on near‐term quantum computers. It is based on McLachlan's variational principle applied to imaginary time evolution of variational wave functions. The variational parameters evolve deterministically according to equations of motions that minimize the difference to the exact imaginary time evolution, which is quantified by the McLachlan distance. Rather than working with a fixed variational ansatz, where the McLachlan distance is constrained by the quality of the ansatz, the AVQITE method iteratively expands the ansatz along the dynamical path to keep the McLachlan distance below a chosen threshold. This ensures the state is able to follow the quantum imaginary time evolution path in the system Hilbert space rather than in a restricted variational manifold set by a predefined fixed ansatz. AVQITE is used to prepare ground states of H 4 , H 2 O, and BeH 2 molecules, where it yields compact variational ansätze and ground state energies within chemical accuracy. Polynomial scaling of circuit depth with system size is shown through a set of AVQITE calculations of quantum spin models. Finally, quantum Lanczos calculations are demonstrated alongside AVQITE without additional quantum resource costs.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗