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Liu, Yan

Publications and source records attributed to Liu, Yan.

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Safety perceptions of solid-state lithium metal batteries

Safety concerns hamper the wide application of lithium-ion batteries (LIBs) in the fields of electric vehicles and stationary energy storage. As the blame of the battery thermal runway was widely cast on the flowable, volatile, and flammable nature of liquid organic electrolytes, solid-state lithium batteries with solid and nonflammable electrolytes are highly praised for potentially better safety characteristics. Furthermore, solid-state lithium metal batteries (SS-LMBs) may become an ultimate solution for safe, high-energy density batteries. Whether SS-LMBs are safe enough to meet emerging demands remains unclear, as recent publications have presented serious safety concerns at both the material and device levels. In conclusion, this review summarizes recent investigations into SS-LMB safety, and systematic analysis and discussion are provided in this discussion of the safety concerns of SS-LMBs.

25 ENERGY STORAGE↗
DOE OSTI2023

Assessing Compatibility of Natural Gas Pipeline Materials with Hydrogen, CO 2 , and Ammonia

Here, in this study, we examine the efficacy of repurposing natural gas (NG) pipelines for transporting hydrogen blends (with NG), ammonia, and CO 2 (gaseous and supercritical) from the standpoint of materials compatibility. Some information pertaining to component performance is also included, especially those components critical for pressurization and monitoring of flow. A listing of critical pipeline components and materials was developed, and their compatibilities was assessed for each fluid or gas type based on known compatibilities. Results indicate that pipeline materials should be suitable for gaseous CO 2 and anhydrous ammonia, but hydrogen blends greater than 12% may be problematic. Current compressor/regulator stations will not be suitable for use with either supercritical CO 2 or ammonia. Important knowledge gaps were identified, including (1) polymer performance with hydrogen/NG blends at low pressures, (2) compressor/regulator station polymers and epoxy coating materials with supercritical CO 2 , and (3) metal performances of hydrogen/NG blends at low pressures.

03 NATURAL GAS↗
DOE OSTI2022

Two‐Dimensional Excitonic Networks Directed by DNA Templates as an Efficient Model Light‐Harvesting and Energy Transfer System

Abstract Photosynthetic organisms organize discrete light‐harvesting complexes into large‐scale networks to facilitate efficient light collection and utilization. Inspired by nature, herein, synthetic DNA templates were used to direct the formation of dye aggregates with a cyanine dye, K21, into discrete branched photonic complexes, and two‐dimensional (2D) excitonic networks. The DNA templates ranged from four‐arm DNA tiles, ≈10 nm in each arm, to 2D wireframe DNA origami nanostructures with different geometries and varying dimensions up to 100×100 nm. These DNA‐templated dye aggregates presented strongly coupled spectral features and delocalized exciton characteristics, enabling efficient photon collection and energy transfer. Compared to the discrete branched photonic systems templated on individual DNA tiles, the interconnected excitonic networks showed approximately a 2‐fold increase in energy transfer efficiency. This bottom‐up assembly strategy paves the way to create 2D excitonic systems with complex geometries and engineered energy pathways.

Zhou, Xu↗
DOE OSTI2022

Two–Dimensional Excitonic Networks Directed by DNA Templates as an Efficient Model Light–Harvesting and Energy Transfer System

Photosynthetic organisms organize discrete light-harvesting complexes into large-scale networks to facilitate efficient light collection and utilization. Inspired by nature, herein, synthetic DNA templates were used to direct the formation of dye aggregates with a cyanine dye, K21, into discrete branched photonic complexes, and two-dimensional (2D) excitonic networks. The DNA templates ranged from four-arm DNA tiles, ≈10 nm in each arm, to 2D wireframe DNA origami nanostructures with different geometries and varying dimensions up to 100×100 nm. These DNA-templated dye aggregates presented strongly coupled spectral features and delocalized exciton characteristics, enabling efficient photon collection and energy transfer. Compared to the discrete branched photonic systems templated on individual DNA tiles, the interconnected excitonic networks showed approximately a 2-fold increase in energy transfer efficiency. Lastly, this bottom-up assembly strategy paves the way to create 2D excitonic systems with complex geometries and engineered energy pathways.

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

An intensity-based post-processing tool for 3D instance segmentation of organelles in soft X-ray tomograms

Investigating the 3D structures and rearrangements of organelles within a single cell is critical for better characterizing cellular function. Imaging approaches such as soft X-ray tomography have been widely applied to reveal a complex subcellular organization involving multiple inter-organelle interactions. However, 3D segmentation of organelle instances has been challenging despite its importance in organelle characterization. Here we propose an intensity-based post-processing tool to identify and separate organelle instances. Our tool separates sphere-like (insulin vesicle) and columnar-shaped organelle instances (mitochondrion) based on the intensity of raw tomograms, semantic segmentation masks, and organelle morphology. We validate our tool using synthetic tomograms of organelles and experimental tomograms of pancreatic β -cells to separate insulin vesicle and mitochondria instances. As compared to the commonly used connected regions labeling, watershed, and watershed + Gaussian filter methods, our tool results in improved accuracy in identifying organelles in the synthetic tomograms and an improved description of organelle structures in β -cell tomograms. In addition, under different experimental treatment conditions, significant changes in volumes and intensities of both insulin vesicle and mitochondrion are observed in our instance results, revealing their potential roles in maintaining normal β -cell function. Our tool is expected to be applicable for improving the instance segmentation of other images obtained from different cell types using multiple imaging modalities.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2022

Three-dimensional structure-guided evolution of a ribosome with tethered subunits

We report RNA-based macromolecular machines, such as the ribosome, have functional parts reliant on structural interactions spanning sequence-distant regions. These features limit evolutionary exploration of mutant libraries and confound three-dimensional structure-guided design. To address these challenges, we describe Evolink (evolution and linkage), a method that enables high-throughput evolution of sequence-distant regions in large macromolecular machines, and library design guided by computational RNA modeling to enable exploration of structurally stable designs. Using Evolink, we evolved a tethered ribosome with a 58% increased activity in orthogonal protein translation and a 97% improvement in doubling times in SQ171 cells compared to a previously developed tethered ribosome, and reveal new permissible sequences in a pair of ribosomal helices with previously explored biological function. The Evolink approach may enable enhanced engineering of macromolecular machines for new and improved functions for synthetic biology.

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

A multi-scale time-series dataset with benchmark for machine learning in decarbonized energy grids

The electric grid is a key enabling infrastructure for the ambitious transition towards carbon neutrality as we grapple with climate change. With deepening penetration of renewable resources, the reliable operation of the electric grid becomes increasingly challenging. In this paper, we present PSML, a first-of-its-kind open-access multi-scale time-series dataset, to aid in the development of data-driven machine learning (ML)-based approaches towards reliable operation of future electric grids. The dataset is synthesized from a joint transmission and distribution electric grid to capture the increasingly important interactions and uncertainties of the grid dynamics, containing power, voltage and current measurements over multiple spatio-temporal scales. Using PSML, we provide state-of-the-art ML benchmarks on three challenging use cases of critical importance to achieve: (i) early detection, accurate classification and localization of dynamic disturbances; (ii) robust hierarchical forecasting of load and renewable energy; and (iii) realistic synthetic generation of physical-law-constrained measurements. We envision that this dataset will provide use-inspired ML research in safety-critical systems, while simultaneously enabling ML researchers to contribute towards decarbonization of energy sectors.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

An overview of visualization and visual analytics applications in water resources management

Recent advances in information, communication, and environmental monitoring technologies have increased the availability, spatiotemporal resolution, and quality of water-related data, thereby leading to the emergence of many innovative big data applications. Among these applications, visualization and visual analytics, also known as the visual computing techniques, empower the synergy of computational methods (e.g., machine learning and statistical models) with human reasoning to improve the understanding and solution toward complex science and engineering problems. These approaches are frequently integrated with geographic information systems and cyberinfrastructure to provide new opportunities and methods for enhancing water resources management. Here, we present a comprehensive review of recent hydroinformatics applications that employ visual computing techniques to (1) support complex data-driven research problems, and (2) support the communication and decision-makings in the water resources management sector. Then, we conduct a technical review of the state-of-the-art web-based visualization technologies and libraries to share our experiences on developing shareable, adaptive, and interactive visualizations and visual interfaces for water resources management applications. We close with a vision that applies the emerging visual computing technologies and paradigms to develop the next generation of hydroinformatics applications.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Alternative splicing of OsGS1;1 affects nitrogen‐use efficiency, grain development, and amylose content in rice

SUMMARY Excessive nitrogen fertilizer application is harmful to the environment and reduces the quality of cereal crops. Maintaining crop yields under low nitrogen (LN) conditions and improving quality are important goals for cereal crop breeding. Although the effects of nitrogen assimilation on crop nitrogen‐use efficiency (NUE) have been intensively studied, natural variations of the key assimilation genes underlying grain development and quality are largely unclear. Here, we identified an NUE‐associated gene, OsGS1;1 , encoding glutamine synthase, through genome‐wide association analysis, followed by validation experiments and functional analysis. Fifteen single‐nucleotide polymorphisms in the OsGS1;1 region led to alternative splicing that generated two functional transcripts: OsGS1;1a and OsGS1;1b . The elite haplotype of OsGS1;1 showed high OsGS1;1b activity, which improved NUE, affected grain development, and reduced amylose content. The results show that OsGS1;1 , which is induced under LN conditions, affects grain formation by regulating sugar metabolism and may provide a new avenue for the breeding of high‐yield and high‐quality rice ( Oryza sativa ).

Liu, Xiaolan↗
DOE OSTI2022

Hall Effect Study of the Metamagnetic Transition in the Sr 4 (Ru 0.99 Fe 0.01 ) 3 O 10 Nanosheet

Sr 4 (Ru 0.99 Fe 0.01 ) 3 O 10 shows a ferromagnetic (FM) transition at T C ~ 105 K with the magnetic easy axis in the ab plane, followed by a metamagnetic transition (MMT) at low temperatures when the magnetic field H is applied along the c axis, which is in sharp contrast to that of the pure Sr 4 Ru 3 O 10 , where the easy axis is along the c axis and the MMT is in the ab plane. Here, we studied the MMT in the Sr 4 (Ru 0.99 Fe 0.01 ) 3 O 10 nanosheet by the Hall effect. It was found that the ordinary Hall coefficient of Sr 4 (Ru 0.99 Fe 0.01 ) 3 O 10 is almost the same as that of the pure Sr 4 Ru 3 O 10 , while a sudden increase in the Hall resistance R xy is observed below ~50 K, above which the R xy presents the conventional anomalous Hall effect up to T C . Analysis of the results indicates that the MMT has no direct correlation to the electronic structure but closely relates to the magnetic moment locking, where the magnetic-field-induced breakdown of the locked moments is responsible for the MMT.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Can Li: A Career in Catalysis

Prof. Can Li is distinguished for his seminal achievements in fundamental and applied researches in catalysis, especially in advancing the characterization of catalysts and catalytic reactions related to solar energy conversion and fine chemical synthesis. The scope of his research is wide ranging, and he is leading some of the fields. This account highlights his major scientific achievements in advancing the fundamental sciences of characterizing catalysts and understanding the mechanisms of catalytic reactions by developing in situ spectroscopic techniques (e.g., infrared (IR), ultraviolet (UV), Raman, space- and time-resolved spectroscopies and photoelectric imaging), and applying the obtained knowledge in the rational design and synthesis of catalysts for practical applications in photocatalytic, electrocatalytic and photoelectrocatalytic water splitting and CO 2 reduction, chiral synthesis in nanoreactors and ultradeep desulfurization of fuels, and fine chemical synthesis. In particular, his demonstration of the kiloton scale solar fuel production project will be introduced as a successful model for converting fundamental science into practical and impactful applications to convert CO 2 and water into solar fuels. This account also highlights his services to the catalysis communities and international collaborations for promoting catalysis science worldwide.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗