检索结果-内蒙古大学图书馆

arXiv 2025年

作者： Mueller, Niclas S. Fellows, Alexander P. John, Ben Naclerio, Andrew E. Carbogno, Christian Gharagozloo-Hubmann, Katayoun Baláž, Damián Kowalski, Ryan A. Heenen, Hendrik H. Scheurer, Christoph Reuter, Karsten Caldwell, Joshua D. Wolf, Martin Kidambi, Piran R. Thämer, Martin Paarmann, Alexander Department of Physical Chemistry Fritz-Haber-Institute of the Max-Planck-Society Berlin14195 Germany Department of Chemical and Biomolecular Engineering Vanderbilt University NashvilleTN37235 United States Theory Department Fritz-Haber-Institute of the Max-Planck-Society Berlin14195 Germany Department of Physics Freie Universität Berlin Berlin14195 Germany Department of Mechanical Engineering Vanderbilt University NashvilleTN37235 United States Interdisciplinary Materials Science Program Vanderbilt University NashvilleTN37235 United States

Hexagonal boron nitride (hBN) is an important 2D material for van der Waals heterostructures, single photon emitters, and infrared nanophotonics. The optical characterization of mono- and few-layer samples of hBN however remains a challenge as the material is almost invisible optically. Here we introduce phase-resolved sum-frequency microscopy as a technique for imaging monolayers of hBN grown by chemical vapor deposition (CVD) and visualize their crystal orientation. A combination of femtosecond mid-infrared (IR) and visible laser pulses is used for sum-frequency generation (SFG), which is imaged in a wide-field optical microscope. The IR laser resonantly excites a phonon of hBN that leads to an ~800-fold enhancement of the SFG intensity, making it possible to image large 100x100 µm2 sample areas in less than 1 s. Implementing heterodyne detection in combination with azimuthal rotation of the sample further provides full crystallographic information. Through combined knowledge of topography and crystal orientation, we find that triangular domains of CVD-grown monolayer hBN have nitrogen-terminated zigzag edges. Overall, SFG microscopy can be used as an ultra-sensitive tool to image crystal structure, strain, stacking sequences, and twist angles, and is applicable to the wide range of van der Waals structures, where location and identification of monolayer regions and interfaces with broken inversion symmetry is of paramount importance. © 2025, CC BY.

关键词： Van der Waals forces

来源：评论

学校读者我要写书评

暂无评论

Long-and short-range orders in 10-component compositionally complex ceramics

Advanced Powder Materials

引用

Advanced Powder materials 2023年第2期2卷 70-81页

作者： Dawei Zhang Yan Chen Heidy Vega Tianshi Feng Dunji Yu Michelle Everett Joerg Neuefeind Ke An Renkun Chen Jian Luo Program of Materials Science and Engineering University of California San DiegoLa Jolla 92093USA Neutron Scattering Division Oak Ridge National LaboratoryOak Ridge 38731USA Department of Biochemistry and Chemistry University of California San DiegoLa Jolla 92093USA Department of Mechanical&Aerospace Engineering University of California San DiegoLa Jolla 92093USA Department of NanoEngineering University of California San DiegoLa Jolla 92093USA

Neutron diffraction and total scattering are combined to investigate a series of single-phase 10-component compositionally complexﬂuorite-based oxides,[(Pr_(0.375)Nd_(0.375)Yb_(0.25))2(Ti_(0.5)Hf_(0.25)Zr_(0.25))_(2)O_(7)]_(1-x)[(DyHoErNb)O_(7)]_(x),denoted as 10CCFBOxNb.A long-range order-disorder transition(ODT)occurs at x=0.81±0.01 from the ordered pyrochlore to disordered defectﬂ*** contrast to ternary oxides,this ODT occurs abruptly without an observable two-phase region;moreover,the phase stability in 10CCFBOs deviates from the well-established criteria for simpler *** reﬁnements of neutron diffraction patterns suggest that this ODT occurs via the migration of oxygen anions from the position 48f to 8a,with a smallﬁnal jump at the ODT;however,the 8a oxygen occupancy changes gradually(without an observable discontinuous jump).We further discover diffuse scattering in Nb-rich compositions,which suggests the presence of short-range *** small-box modelling,four compositions near ODT(x=0.75,0.8,0.85,and 1)can be betterﬁtted by C2221 weberite ordering for the local polyhedral structure at ***,10CCFBO_(0.75)Nb and 10CCFBO_(0.8)Nb possess both long-range pyrochlore order and short-range weberite-type order,which can be understood from severe local distortion of the pyrochlore polyhedral ***,weberite-type short-range order emerges before the ODT,coexisting and interacting with long-range pyrochlore *** the ODT,the long-range pyrochlore order vanishes but the short-range weberite-type order persists in the long-range disordered defectﬂuorite ***,a drop in the thermal conductivity coincides with emergence of the short-range order,instead of the long-range ODT.

关键词： Neutron diffraction Neutron total scattering Order-disorder transition Short-range order High-entropy ceramics Compositionally complex ceramics

来源：评论

学校读者我要写书评

暂无评论

Architecture Optimization Dramatically Improves Reverse Bias Stability in Perovskite Solar Cells: A Role of Polymer Hole Transport Layers

arXiv

引用

arXiv 2023年

作者： Jiang, Fangyuan Shi, Yangwei Rana, Tanka R. Morales, Daniel Gould, Isaac McCarthy, Declan P. Smith, Joel Christoforo, Grey Contreras, Hannah Barlow, Stephen Mohite, Aditya D. Snaith, Henry Marder, Seth R. MacKenzie, J. Devin McGehee, Michael D. Ginger, David S. Department of Chemistry University of Washington SeattleWA98195 United States Molecular Engineering & Sciences Institute University of Washington SeattleWA98195 United States Department of Materials Science and Engineering University of Washington SeattleWA98195 United States Materials Science and Engineering Program University of Colorado Boulder BoulderCO80309 United States Renewable and Sustainable Energy Institute University of Colorado Boulder BoulderCO80303 United States Department of Physics University of Oxford Parks Road OxfordOX1 3PU United Kingdom Department of Materials Science and NanoEngineering Rice University HoustonTX77005 United States Department of Chemical and Biological Engineering Department of Chemistry University of Colorado Boulder BoulderCO80303 United States Department of Mechanical Engineering University of Washington SeattleWA98195 United States

We report that device architecture engineering has a substantial impact on the reverse bias instability that has been reported as a critical issue in commercializing perovskite solar cells. We demonstrate breakdown voltages exceeding -15 V in typical p-i-n structured perovskite solar cells via two steps: i) using polymer hole transporting materials;ii) using a more electrochemically stable gold electrode. While device degradation can be exacerbated by higher reverse bias and prolonged exposure, our as-fabricated perovskite solar cells completely recover their performance even after stressing at -7 V for 9 hours both in the dark and under partial illumination. Following these observations, we systematically discuss and compare the reverse bias driven degradation pathways in perovskite solar cells with different device architectures. Our model highlights the role of electrochemical reaction rates and species in dictating the reverse bias stability of perovskite solar cells. Copyright © 2023, The Authors. All rights reserved.

关键词： Perovskite solar cells

来源：评论

学校读者我要写书评

暂无评论

Reconfigurable Assembly of Chiral Metamaterials on Solid Substrates

Reconfigurable Assembly of Chiral Metamaterials on Solid Sub...

引用

Novel Optical materials and Applications, NOMA 2020

作者： Li, Jingang Zheng, Yuebing Materials Science and Engineering Program and Texas Materials Institute University of Texas at Austin AustinTX78712 United States Department of Mechanical Engineering University of Texas at Austin AustinTX78712 United States

We report an all-optical approach to build colloids into active chiral nanostructures on a solid substrate, where the chiroptical response can be tailored on-demand. © 2020 OSA - The Optical Society. All rights r... 详细信息

ISBN: (纸本)9781943580798

关键词： Substrates

来源：评论

学校读者我要写书评

暂无评论

A Biphasic Liquid System for Low-Power Optothermal Bubble Generation and Enhanced Surface Binding of Proteins

A Biphasic Liquid System for Low-Power Optothermal Bubble Ge...

引用

Novel Optical materials and Applications, NOMA 2020

作者： Kim, Youngsun Zheng, Yuebing Materials Science and Engineering Program and Texas Materials Institute University of Texas at Austin AustinTX78712 United States Department of Mechanical Engineering University of Texas at Austin AustinTX78712 United States

A perfluoropentane-in-water biphasic system, capable of optothermally generating microbubbles at low power, enhanced surface binding of protein by the bulk-To-surface concentration with minimal loss in its activity. &... 详细信息

ISBN: (纸本)9781943580798

关键词： Proteins

来源：评论

学校读者我要写书评

暂无评论

Eco-Friendly High Entropy Oxide Rock-Salt Type Structure for Oxygen Evolution Reaction Obtained by Green Synthesis Using Red Seaweed (Rhodophyta)

SSRN

引用

SSRN 2024年

作者： Santos, Jakeline RAIANE DORA DOS Raimundo, Rafael A. de Oliveira, João F.G.A. Hortencio, Johnnys da S. Loureiro, Francisco J.A. Macedo, Daniel A. Morales, Marco A. Gualandi, Isacco Tonelli, Domenica Gomes, Uílame U. Materials Science and Engineering Postgraduate Program UFRN Natal59078-970 Brazil Department of Industrial Chemistry "Toso Montanari" Industrial Chemistry UNIBO V.le Risorgimento 4 Bologna40136 Italy Department of Theoretical and Experimental Physics Federal University of Rio Grande do Norte UFRN Natal59078-970 Brazil Gleb Wataghin Institute of Physics - R. Sérgio Buarque de Holanda 777 - Cidade Universitária Campinas13083-859 Brazil Department of Chemistry Federal University of Paraíba UFPB João Pessoa58.051-900 Brazil TEMA - Centre for Mechanical Technology and Automation Mechanical Engineering Department University of Aveiro 3810-193 Portugal LASI - Intelligent Systems Associate Laboratory Portugal Materials Science and Engineering Postgraduate Program Federal University of Paraíba UFPB João Pessoa58051-900 Brazil

Global energy consumption increases year after year, causing the depletion of non-renewable sources. According to the International Energy Agency (IEA), global demand for electrical energy is expected to increase by 3.3% in 2024. Therefore, developing new renewable sources is urgent, including new devices for energy storage and conversion, particularly those governed by electrochemical reactions. Water splitting is a clean and sustainable technology capable of facing this issue by producing oxygen and hydrogen from water and electricity. However, a problem related to this technology is the slow kinetics, making it necessary to develop new electrocatalysts with high electrochemical performance. To meet this requirement, this work deals with for the first time a high entropy oxide with rock-salt structure synthesized by a green solgel synthesis using red seaweed (Rhodophyta) as polymerizing agent. Solgel synthesis allows the large-scale production of nanomaterials with high uniformity and dispersion of the chemical elements involved. The literature, which discussed the production of these oxides, reveals that agents harmful to the environment are applied during the synthesis steps, including sodium hydroxide, acetic acid, hexadecyltrimethylammonium bromide, urea, and ammonia. The composition of the high entropy oxide is (Mg0.2 Ni0.2 Co0.2 Cu0.2 Zn0.2 )O, it displays a low overpotential (336 mV vs. RHE at 10 mA cm-2 ), Tafel slope of 68 mV dec-1 , and excellent durability. The electrochemical performance of the high entropy oxide prepared in this work is superior to other electrocatalysts of the same class that were produced using transition metal-based precursors. © 2024, The Authors. All rights reserved.

关键词： Entropy

来源：评论

学校读者我要写书评

暂无评论

Estimation of the main air pollutants from different biomasses under combustion atmospheres by artificial neural networks

引用

Chemosphere 2024年 352卷 141484页

作者： Monteiro, Thalyssa Oliveira Alves, Pedro Augusto Araújo da Silva de Almeida Nava Barradas Filho, Alex Oliveira Villa-Vélez, Harvey Alexander Cruz, Glauber Postgraduate Program in Mechanical Engineering (PPGMEC) Department of Mechanics and Materials Federal Institute of Education Science and Technology of Maranhão (IFMA) Maranhão São Luís Brazil Postgraduate Program in Computer Science and Computational Mathematics (PPG-CCMC) Department of Computer Science University of São Paulo (USP) São Carlos São Paulo Brazil Data Analysis and Artificial Intelligence Laboratory (DARTi) Department of Computational Engineering Federal University of Maranhão (UFMA) Maranhão São Luís Brazil Department of Chemical Engineering Federal University of Maranhão (UFMA) Maranhão São Luís Brazil Processes and Thermal Systems Laboratory (LPSisTer) Department of Mechanical Engineering Federal University of Maranhão (UFMA) Maranhão São Luís Brazil

The production of biofuels to be used as bioenergy under combustion processes generates some gaseous emissions (CO, CO2, NOx, SOx, and other pollutants), affecting living organisms and requiring careful assessments. H... 详细信息

The production of biofuels to be used as bioenergy under combustion processes generates some gaseous emissions (CO, CO₂, NO_x, SO_x, and other pollutants), affecting living organisms and requiring careful assessments. However, obtaining such information experimentally for data evaluation is costly and time-consuming and its in situ obtaining for regional biomasses (e.g., those from Northeast Brazil (NEB) is still a major challenge. This paper reports on the application of artificial neural networks (ANNs) for the prediction of the main air pollutants (CO, CO₂, NO, and SO₂) produced during the direct biomass combustion (N₂/O₂:80/20%) with the use of ultimate analysis (carbon, hydrogen, nitrogen, sulfur, and oxygen). 116 worldwide biomasses were used as input data, which is a relevant alternative to overcome the lack of experimental resources in NEB and obtain such information. Cross-validation was conducted with k-fold to optimize the ANNs and performance was analyzed with the use of statistical errors for accuracy assessments. The results showed an acceptable statistical performance for all architectures of ANNs, with 0.001–12.41% MAPE, 0.001–5.82 mg Nm⁻³ MAE, and 0.03–52.30 mg Nm⁻³ RMSE, highlighting the high precision of the emissions studied. On average, the differences between predicted and real values for CO, CO₂, NO, and SO₂ emissions from NEB biomasses were approximately 0.01%, 10⁻⁶%, 0.14%, and 0.05%, respectively. Pearson coefficient provided consistent results of concentration of the ultimate analysis in relation to the emissions studied and effectiveness of the test set in the developed models. © 2024 Elsevier Ltd

关键词： Brazilian northeastern Environmental statistics Evaluation metrics Gaseous emissions Predictive models Thermoconversion

来源：评论

学校读者我要写书评

暂无评论

Identifying the minimal sets of distance restraints for FRET-assisted protein structural modeling

arXiv

引用

arXiv 2024年

作者： Liu, Zhuoyi Grigas, Alex T. Sumner, Jacob Knab, Edward Davis, Caitlin M. O’Hern, Corey S. Department of Mechanical Engineering and Materials Science Yale University New HavenCT06520 United States Integrated Graduate Program in Physical and Engineering Biology Yale University New HavenCT06520 United States Graduate Program in Computational Biology and Bioinformatics Yale University New HavenCT06520 United States Department of Chemistry Yale University New HavenCT06520 United States Department of Physics Yale University New HavenCT06520 United States Department of Applied Physics Yale University New HavenCT06520 United States

Proteins naturally occur in crowded cellular environments and interact with other proteins, nucleic acids, and organelles. Since most previous experimental protein structure determination techniques require that proteins occur in idealized, non-physiological environments, the effects of realistic cellular environments on protein structure are largely unexplored. Recently, Förster resonance energy transfer (FRET) has been shown to be an effective experimental method for investigating protein structure in vivo. Inter-residue distances measured in vivo can be incorporated as restraints in molecular dynamics (MD) simulations to model protein structural dynamics in vivo. Since most FRET studies only obtain inter-residue separations for a small number of amino acid pairs, it is important to determine the minimum number of restraints in the MD simulations that are required to achieve a given root-mean-square deviation (RMSD) from the experimental structural ensemble. Further, what is the optimal method for selecting these inter-residue restraints? Here, we implement several methods for selecting the most important FRET pairs and determine the number of pairs Nr that are needed to induce conformational changes in proteins between two experimentally determined structures. We find that enforcing only a small fraction of restraints, Nr/N 0.08, where N is the number of amino acids, can induce the conformational changes. These results establish the efficacy of FRET-assisted MD simulations for atomic scale structural modeling of proteins in vivo. © 2024, CC BY.

关键词： Conformations

来源：评论

学校读者我要写书评

暂无评论

Ortho-positronium Lifetime For Soft-tissue Classification

arXiv

引用

arXiv 2024年

作者： Avachat, Ashish V. Mahmoud, Kholod H. Leja, Anthony G. Xu, Jiajie J. Anastasio, Mark A. Sivaguru, Mayandi Di Fulvio, Angela Department of Mechanical Engineering and Materials Science University of Pittsburgh United States Department of Bioengineering University of Illinois Urbana-Champaign United States Department of Nuclear Plasma and Radiological Engineering University of Illinois Urbana-Champaign United States Department of Clinical Medicine University of Illinois Urbana-Champaign United States Animal Care Program University of Illinois Urbana-Champaign United States Cytometry and Microscopy to Omics Facility Roy J Carver Biotechnology Center University of Illinois Urbana-Champaign United States

The objective of this work is to showcase the ortho-positronium lifetime as a probe for soft-tissue characterization. We employed positron annihilation lifetime spectroscopy to experimentally measure the three components of the positron annihilation lifetime-para-positronium (p-Ps), positron, and ortho-positronium (o-Ps)-for three types of porcine, non-fixated soft tissues ex vivo: adipose, hepatic, and muscle. Then, we benchmarked our measurements with X-ray phase-contrast imaging, which is the current state-of-the-art for soft-tissue analysis. We found that the o-Ps lifetime in adipose tissues (2.54 }0.12 ns) was approximately 20% longer than in hepatic (2.04 }0.09 ns) and muscle (2.03 }0.12 ns) tissues. In addition, the separation between the measurements for adipose tissue and the other tissues was better from o-Ps lifetime measurement than from X-ray phase-contrast imaging. This experimental study proved that the o-Ps lifetime is a viable non-invasive probe for characterizing and classifying the different soft tissues. Specifically, o-Ps lifetime as a soft-tissue characterization probe had a strong sensitivity to the lipid content that can be potentially implemented in commercial positron emission tomography scanners that feature list-mode data acquisition. © 2024, CC BY-NC-ND.

关键词： Probes

来源：评论

学校读者我要写书评

暂无评论

Spectroscopic and Interferometric Sum-Frequency Imaging of Strongly Coupled Phonon Polaritons in SiC Metasurfaces

arXiv

引用

arXiv 2023年

作者： Niemann, Richarda Mueller, Niclas S. Wasserroth, Sören Lu, Guanyu Wolf, Martin Caldwell, Joshua D. Paarmann, Alexander Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6 Berlin14195 Germany Department of Mechanical Engineering Vanderbilt University NashvilleTN37235 United States Interdisciplinary Materials Science Graduate Program Vanderbilt University NashvilleTN37235 United States

Phonon polaritons enable waveguiding and localization of infrared light with extreme confinement and low losses. The spatial propagation and spectral resonances of such polaritons are usually probed with complementary techniques such as near-field optical microscopy and far-field reflection spectroscopy. Here, we introduce infrared-visible sum-frequency spectro-microscopy as a tool for spectroscopic imaging of phonon polaritons. The technique simultaneously provides sub-wavelength spatial resolution and highly-resolved spectral resonance information. This is implemented by resonantly exciting polaritons using a tunable infrared laser and wide-field microscopic detection of the upconverted light. We employ this technique to image hybridization and strong coupling of localized and propagating surface phonon polaritons in metasurfaces of SiC micropillars. Spectro-microscopy allows us to measure the polariton dispersion simultaneously in momentum space by angle-dependent resonance imaging, and in real space by polariton interferometry. Notably, we directly visualize how strong coupling affects the spatial localization of polaritons, inaccessible with conventional spectroscopic techniques. We further observe the formation of edge states at excitation frequencies where strong coupling prevents polariton propagation into the metasurface. Our approach is applicable to the wide range of polaritonic materials with broken inversion symmetry and can be used as a fast and non-perturbative tool to image polariton hybridization and propagation. © 2023, CC BY.

关键词： Polariton

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：