Search

Your search keyword '"Meng, Lingyao"' showing total 82 results
Start Over Author "Meng, Lingyao"
82 results on '"Meng, Lingyao"'

59. Shape Dependence of Pressure-Induced Phase Transition in CdS Semiconductor Nanocrystals

Author

Meng, Lingyao, primary, Lane, J. Matthew D., additional, Baca, Luke, additional, Tafoya, Jackie, additional, Ao, Tommy, additional, Stoltzfus, Brian, additional, Knudson, Marcus, additional, Morgan, Dane, additional, Austin, Kevin, additional, Park, Changyong, additional, Chow, Paul, additional, Xiao, Yuming, additional, Li, Ruipeng, additional, Qin, Yang, additional, and Fan, Hongyou, additional

Published
2020
Full Text
View/download PDF

63. High pressure induced atomic and mesoscale phase behaviors of one-dimensional TiO2anatase nanocrystals

Author

Meng, Lingyao, Duwal, Sakun, Lane, J. Matthew D., Ao, Tommy, Stoltzfus, Brian, Knudson, Marcus, Park, Changyong, Chow, Paul, Xiao, Yuming, Fan, Hongyou, and Qin, Yang

Abstract

Abstract: Here, we report the high pressure phase and morphology behavior of ordered anatase titanium dioxide (TiO2) nanocrystal arrays. One-dimensional TiO2nanorods and nanorices were synthesized and self-assembled into ordered mesostructures. Their phase and morphological transitions at both atomic scale and mesoscale under pressure were studied using in situsynchrotron wide- and small-angle x-ray scattering (WAXS and SAXS) techniques. At the atomic scale, synchrotron WAXS reveals a pressure-induced irreversible amorphization up to 35 GPa in both samples but with different onset pressures. On the mesoscale, no clear phase transformations were observed up to 20 GPa by synchrotron SAXS. Intriguingly, sintering of TiO2nanorods at mesoscale into nano-squares or nano-rectangles, as well as nanorices into nanowires, were observed for the first time by transmission electron microscopy. Such pressure-induced nanoparticle phase-amorphization and morphological changes provide valuable insights for design and engineering structurally stable nanomaterials. Impact statement: The high pressure behavior of nanocrystals (NCs) continues to be of interest, as previous studies have demonstrated that an externally applied pressure can serve as an efficient tool to induce structural phase transitions of NC assemblies at both the atomic scale and mesoscale without altering any chemistry by manipulating NC interatomic and interparticle distances. In addition, the high pressure generated deviatoric stress has been proven to be able to force adjacent NCs to connect and fuse into new crystalline nanostructures. Although the atomic structural evolution of TiO2NCs under pressure has been widely investigated in the past decades, open questions remain regarding the mesoscale phase transition and morphology of TiO2NC assemblies as a function of pressure. Therefore, in this work, systemic high pressure experiments on ordered arrays of TiO2nanorods and nanorices were conducted by employing wide/small angle x-ray scattering techniques. The sintering of TiO2assemblies at mesoscale into various nanostructures under pressure were revealed by transmission electron microscopy. Overall, this high pressure work fills the current gap in research on the mesoscale phase behavior of TiO2assemblies. The observed morphology tunability attained by applying pressure opens new pathways for engineering nanomaterials and optimizing their collective properties through mechanical compression stresses. Graphical abstract:

Published
2022
Full Text
View/download PDF

64. Charge‐Separated and Lewis Paired Metal–Organic Framework for Anion Exchange and CO2 Chemical Fixation.

Author

Thapa, Sheela, Meng, Lingyao, Hettiarachchi, Eshani, Bader, Yousef K., Dickie, Diane A., Rubasinghege, Gayan, Ivanov, Sergei A., Vreeland, Erika C., and Qin, Yang

Subjects
*LEWIS pairs (Chemistry), *METAL-organic frameworks, *CHEMICAL reactions, *ANIONS, *LEWIS bases, *ION-permeable membranes, *PYRAZOLYL compounds
Abstract

Charge‐separated metal–organic frameworks (MOFs) are a unique class of MOFs that can possess added properties originating from the exposed ionic species. A new charge‐separated MOF, namely, UNM‐6 synthesized from a tetrahedral borate ligand and Co2+ cation is reported herein. UNM‐6 crystalizes into the highly symmetric P43n space group with fourfold interpenetration, despite the stoichiometric imbalance between the B and Co atoms, which also leads to loosely bound NO3− anions within the crystal structure. These NO3− ions can be quantitatively exchanged with various other anions, leading to Lewis acid (Co2+) and Lewis base (anions) pairs within the pores and potentially cooperative catalytic activities. For example, UNM‐6‐Br, the MOF after anion exchange with Br− anions, displays high catalytic activity and stability in reactions of CO2 chemical fixation into cyclic carbonates. [ABSTRACT FROM AUTHOR]

Published
2020
Full Text
View/download PDF

65. Conjugation of Indoles to Antibodies through a Novel Self-Immolating Linker

Author

Dragovich, Peter S., primary, Blake, Robert A., additional, Chen, Chunjiao, additional, Chen, Jinhua, additional, Chuh, Josefa, additional, den Besten, Willem, additional, Fan, Fang, additional, Fourie, Aimee, additional, Hartman, Steven J., additional, He, Changrong, additional, He, Jintang, additional, Ingalla, Ellen Rei, additional, Kozak, Katherine R., additional, Leong, Steven R., additional, Lu, Jiawei, additional, Ma, Yong, additional, Meng, Lingyao, additional, Nannini, Michelle, additional, Oeh, Jason, additional, Ohri, Rachana, additional, Lewis Phillips, Gail, additional, Pillow, Thomas H., additional, Rowntree, Rebecca K., additional, Sampath, Deepak, additional, Vandlen, Richard, additional, Vollmar, Breanna, additional, Wai, John, additional, Wertz, Ingrid E., additional, Xu, Keyang, additional, Xu, Zijin, additional, and Zhang, Donglu, additional

Published
2018
Full Text
View/download PDF

73. Crystallization Kinetics of Functionalized Fe 3 O 4 /Ethylene-vinyl Acetate Copolymer Nanocomposites Adhesives.

Author

Zhang, Rui, He, Xianru, Chen, Qian, Feng, Chunhui, and Meng, Lingyao

Subjects
CRYSTALLIZATION, CHEMICAL kinetics, IRON oxides, NANOCOMPOSITE materials, ADHESIVES, X-ray scattering
Abstract

In the present paper, the crystallization behaviors of six different functional Fe3O4/ethylene-vinyl acetate (EVA) copolymer nanocomposite adhesives were studied. Crystal structures of the nanocomposite adhesives were characterized by wide-angle X-ray scattering, and the results showed that both functionalized and non-functionalized Fe3O4nanoparticles had only a small influence on the crystal structure of EVA. The cystallization kinetics was investigated through differential scanning calorimetry. The Ozawa and Mo methods were applied to analyze the crystallization behaviors, and the nucleating effect was estimated through the Dobreva and Gutzow method. Finally, the crystallization energy barrier was studied by the Kissinger method. [ABSTRACT FROM AUTHOR]

Published
2016
Full Text
View/download PDF

76. Sociodemographic and Psychological Predictors of Resilience Among Frontline Nurses Fighting the COVID-19 Pandemic

Author

Zhang, Yan, Xiong, Yang, Zhang, Lei, Jiang, Xiaofeng, Zhuang, Xiaoqian, Meng, Lingyao, Peng, Lingli, and Wu, Jing

Abstract

AbstractObjective:According to a WHO report, the number of patients with coronavirus disease 2019 (COVID-19) has reached 456,797,217 worldwide as of 15 March, 2022. In Wuhan, China, large teams of health-care personnel were dispatched to respond to the COVID-19 emergency. This study aimed to determine the sociodemographic and psychological predictors of resilience among frontline nurses fighting the current pandemic.Methods:A total of 143 nurses were recruited from February 15 to February 20, 2020, to participate in this study. The 10-item Connor-Davidson Resilience Scale and the 21-item Depression Anxiety Stress Scale were used to estimate the participants’ resilience and mental wellbeing.Results:Results showed that the nurses displayed a moderate resilience level. Their median depression, anxiety, and stress scores were 1, 2, and 3, respectively, which were negatively correlated with resilience. Female gender, being dispatched to Wuhan, and depression levels were the significant predictors of resilience.Conclusions:The results suggest that particular attention should be given to nurses who were dispatched to Wuhan and who exhibited depression symptoms, and appropriate measures should be taken to boost their resilience.

Published
2023
Full Text
View/download PDF

79. Synthesis, Self-Assembly and High-Pressure Properties of Nanoparticles and Hybrid Nanocomposites

Author

Meng, Lingyao

Subjects
nanoparticles, conjugated polymers, photovoltaic, metal-organic frameworks, high pressure, Nanoscience and Nanotechnology, Polymer Science, Semiconductor and Optical Materials
Abstract

Nanoparticles have gained significant scientific interests owing to their unique structural dimensions, size- and shape-tunable properties, and numerous fascinating applications, from opto-electronics, sensor devices, to energy, environmental, and medical fields. Furthermore, the synergistic integration of other materials, including organic polymers, with nanoparticles provides new opportunities and strategies to obtain nanocomposites with superior properties and functionalities. While there is already significant research on the synthesis and characterizations of nanoparticles and hybrid nanocomposites, some research questions, such as how to design and control the interfacial morphology in polymer/nanoparticle hybrid nanocomposites, how to synthesize metal- organic framework (MOF) nanoparticles in well-defined and uniform sizes and shapes, and how the size and shape of nanoparticles affect their properties under high pressures, are still challenges of today. In order to tackle these challenges, this research thesis focuses on the synthesis, self-assembly and high-pressure properties of three different classes of nanoparticles or hybrid nanocomposite materials. In the first part of this thesis, hybrid nanocomposites of conjugated polymers and inorganic nanoparticles are discussed, and a novel supramolecular strategy to assemble polymers and nanoparticles into stable and well-ordered core/shell composite nanofibers through the cooperation of several non-covalent interactions (hydrogen bonding, π-π interactions, etc.) is examined. By synthesizing conjugated polymers with specific functional groups (e.g. pyridine), we have successfully attached CdSe quantum dots and Fe3O4 nanoparticles non-covalently onto the polymer nanofibers. Besides the excellent conducting property of the conjugated polymer, the resulting nanocomposites also show some added benefits, such as broader light absorption range when combined with quantum dots as well as added magnetic responsiveness when combined with iron oxide nanoparticles. Further incorporation of such composite nanofibers into organic photovoltaic devices has led to the formation of well-dispersed photoactive layer morphology. This strategy can be used as general design principles for assembling incompatible hybrid nanocomponents into well-ordered structures. The second part of this thesis focuses on formation strategies and mechanisms for well-defined one-dimensional (1D) MOF nanostructures. Unlike inorganic and organic nanoparticles, for which synthetic procedures have well been established, generalizable design and preparation of MOF nanoparticles are still under early developing stages. To address this challenge, we have developed a new method to rapidly and reproducibly synthesize continuous 1-D MOF nano/micro-structures through interfacial synthesis templated by nanoporous polymer membranes. In this study, zeolitic imidazole frameworks (ZIFs) and polycarbonate track-etched (PCTE) membranes were used as model materials, and by varying the experimental conditions (pore sizes, reaction time,metal ion source, etc.), different 1D ZIF-8 or ZIF-67 nano/micro-structures with the pore dimensions corresponding to the PCTE templates were obtained, which were further fully characterized by a combination of electron microscopy and X-ray techniques. This work represents the first example of membrane templated synthesis of MOF nano/micro- structures. Our findings provide a generalized method for controlling size, morphology, and lattice orientation of MOF nanomaterials. The last part of this thesis discusses how the size and shape of nanoparticles influence their pressure-dependent properties using CdS nanoparticles as a model material. CdS nanoparticles are synthesized in three different sizes and shapes, and are subjected to controlled high pressures up to 15 GPa in a diamond anvil cell. Characterizations with in- situ small and wide-angle X-ray scattering measurements under high pressure suggest that both the reversibility of phase transition and phase transition pressure are closely related to the particle size and shape. Further characterizations with transmission electron microscopy show that external pressure can decrease the nanoparticle separation distance and induce sintering and coalescence of nanoparticles into new nanostructures. Our results provide new insights into the fundamental properties of nanoparticles under high pressure that will inform designs of new nanomaterial structures for emerging applications.

Published
2020

80. Influence of metal-semiconductor junction on the performances of mixed-dimensional MoS 2 /Ge heterostructure avalanche photodetector.

Author

Yuan X, Zhang N, Zhang T, Meng L, Zhang J, Shao J, Liu M, Hu H, and Wang L

Abstract

The two-dimensional/three-dimensional van der Waals heterostructures provide novel optoelectronic properties for the next-generation of information devices. Herein, MoS 2 /Ge heterojunction avalanche photodetectors are readily obtained. The device with an Ag electrode at MoS 2 side exhibits more stable rectification characteristics than that with an Au electrode. The rectification radio greater than 10 3 and a significant avalanche breakdown are observed in the device. The responsivity of 170 and 4 A/W and the maximum gain of 320 and 13 are obtained under 532 and 1550 nm illumination, respectively. Such photoelectric properties are attributed to the carrier multiplication at a Ge/MoS 2 junction due to an avalanche breakdown. The mechanism is confirmed by the Sentaurus TCAD-simulated I-V characteristics.

Published
2022
Full Text
View/download PDF

81. Conjugation of Indoles to Antibodies through a Novel Self-Immolating Linker.

Author

Dragovich PS, Blake RA, Chen C, Chen J, Chuh J, den Besten W, Fan F, Fourie A, Hartman SJ, He C, He J, Ingalla ER, Kozak KR, Leong SR, Lu J, Ma Y, Meng L, Nannini M, Oeh J, Ohri R, Lewis Phillips G, Pillow TH, Rowntree RK, Sampath D, Vandlen R, Vollmar B, Wai J, Wertz IE, Xu K, Xu Z, and Zhang D

Subjects
Animals, Antibodies, Monoclonal chemistry, Cell Line, Tumor, Humans, Immunoconjugates administration & dosage, MCF-7 Cells, Mice, Indoles chemistry
Abstract

A novel strategy to attach indole-containing payloads to antibodies through a carbamate moiety and a self-immolating, disulfide-based linker is described. This new strategy was employed to connect a selective estrogen receptor down-regulator (SERD) to various antibodies in a site-selective manner. The resulting conjugates displayed potent, antigen-dependent down-regulation of estrogen receptor levels in MCF7-neo/HER2 and MCF7-hB7H4 cells. They also exhibited similar antigen-dependent modulation of the estrogen receptor in tumors when administered intravenously to mice bearing MCF7-neo/HER2 tumor xenografts. The indole-carbamate moiety present in the new linker was stable in whole blood from various species and also exhibited good in vivo stability properties in mice., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Published
2018
Full Text
View/download PDF

82. A proteomics analysis of rat liver membrane skeletons: the investigation of actin- and cytokeratin-based protein components.

Author

Wang Q, He J, Meng L, Liu Y, Pu H, and Ji J

Subjects
Animals, Blotting, Western, Cell Membrane chemistry, Cell Membrane ultrastructure, Electrophoresis, Gel, Two-Dimensional, Intercellular Junctions chemistry, Intercellular Junctions metabolism, Liver cytology, Liver metabolism, Rats, Reproducibility of Results, Spectrometry, Mass, Electrospray Ionization, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Actins analysis, Keratins analysis, Liver chemistry, Proteome analysis, Proteomics methods
Abstract

Membrane skeletons, which are defined for their resistance to Triton extraction of cell membrane, play a pivotal role in cell shape and signal transduction. In the present work, we applied a complementary proteomics strategy: 2-DE combined with MALDI-TOF MS and 1D-PAGE coupled with LC-ESI-FTICR MS to analyze a membrane skeleton fraction isolated from Sprague-Dawley (SD) rat livers. We report confident identification of 104 proteins (39 membrane skeleton proteins) using 2-DE and MALDI-TOF MS approach and 402 proteins (87 membrane skeleton proteins) using 1D-PAGE LC-MS/MS analysis. In total, 100 membrane skeleton proteins were identified using the two complementary proteomics means. To the best of our knowledge, this is the largest data set of membrane skeleton proteins to date. Noteworthily, almost all of these membrane skeleton proteins were associated with actin or cytokeratin, and more than half of them were involved in various cell junctions. Our results offer insights into the protein components of the actin- and cytokeratin-based membrane skeletons in rat livers, which would improve our understanding of their biological roles.

Published
2010
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results