检索结果-内蒙古大学图书馆

Optical Trapping and Optical Micromanipulation XVII 2020

作者： Kollipara, Pavana Siddhartha Lin, Linhan Zheng, Yuebing Walker Department of Mechanical Engineering University of Texas at Austin TX78751 United States Materials Science and Engineering Program and Texas Materials Institute University of Texas at Austin TX78751 United States State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision Instrument Tsinghua University Beijing100084 China

ISBN: (纸本)9781510637320

Several studies have been proposed to control particle trajectory in liquid solutions using optically induced thermal gradient. Upon introducing different solutes such as salts and surfactants along with microparticles in these solutions, an additional optically induced thermoelectric trapping force is generated due to the differential motion of ions in the solution under thermal field. As the complexity of the solution increases, it becomes increasing difficult to understand particle response towards laser irradiance. More importantly, the existing models to study the thermoelectric behavior of the particle assumes a constant temperature gradient across the particles, which becomes obsolete in the micro-regime due to discontinuity of thermal conductivity at the particle-solution interface. For a better understanding of trapping and manipulation behavior of particles under light induced thermoelectric field, the temperature gradient distortion must be considered. In this work, full-scale finiteelement solver model has been proposed to determine the temperature variation around a microparticle under laser heating. The resultant temperature distribution is utilized to numerically evaluate the thermoelectric field and the trapping potential of the laser induced opto-thermoelectric trap. To experimentally validate this methodology, polystyrene micro-particles are trapped opto-thermoelectric-ally in CTAC solution and compared the experimental trapping stiffness to theoretical estimates obtained from the model. It is observed that trapping stiffness saturates as surfactant concentration increases which can be optimized by choosing the lowest CTAC concentration at the onset of saturation. The model implemented here can be easily extended to arbitrarily shaped particles, particles with non-uniform surface morphology, different combinations of core-shell particles and electrolyte solutions, which can be implemented to study different phenomenon such as optical pulling, rotat

关键词： Thermal gradients

来源：评论

学校读者我要写书评

暂无评论

Optical Patterning of Two-Dimensional materials

引用

研究（英文） 2020年第2期 63-77页

作者： Pavana Siddhartha Kollipara Jingang Li Yuebing Zheng Walker Department of Mechanical Engineering The University of Texas at Austin Austin TX 78712 USA Materials Science & Engineering Program and Texas Materials Institute The University of Texas at Austin Austin TX 78712 USA Walker Department of Mechanical Engineering The University of Texas at Austin Austin TX 78712 USA Materials Science & Engineering Program and Texas Materials Institute The University of Texas at Austin Austin TX 78712 USA

Recent advances in the field of two-dimensional (2D) materials have led to new electronic and photonic devices enabled by their unique properties at atomic *** 2D materials into desired patterns on substrates is often an essential and foremost step for the optimum performance of the functional *** this regard,optical patterning of 2D materials has received enormous interest due to its advantages of high-throughput,site-specific,and on-demand *** years have witnessed scientific reports of a variety of optical techniques applicable to patterning 2D *** this minireview,we present the state-of-the-art optical patterning of 2D materials,including laser thinning,doping,phase transition,oxidation,and *** applications based on optically patterned 2D materials will be discussed as *** further developments,optical patterning is expected to hold the key in pushing the frontiers of manufacturing and applications of 2D materials.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Chemically Binding Scaffolded Anodes with 3D Graphene Architectures Realizing Fast and Stable Lithium Storage

引用

Research 2019年第1期2019卷 662-670页

作者： Ping Wu Zhiwei Fang Anping Zhang Xiao Zhang Yawen Tang Yiming Zhou Guihua Yu Materials Science and Engineering Program and Department of Mechanical Engineering Te University of Texas at AustinAustinTexas 78712USA Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Center of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China

Tree-dimensional(3D)graphene has emerged as an ideal platform to hybridize with electrochemically active materials for improved ***,for lithium storage,current anodic guests ofen exist in the form of nanoparticles,physically attached to graphene hosts,and therefore tend to detach from graphene matrices and aggregate into large congeries,causing considerable capacity fading upon repeated ***,we develop a facile double-network hydrogel-enabled methodology for chemically binding anodic scafolds with 3D graphene *** tin-based alloy anodes as an example,the doublenetwork hydrogel,containing interpenetrated cyano-bridged coordination polymer hydrogel and graphene oxide hydrogel,is directly converted to a physical-intertwined and chemical-bonded Sn−Ni alloy scafold and graphene architecture(Sn−Ni/G)dual *** unique dual framework structure,with remarkable structural stability and charge-transport capability,enables the Sn−Ni/G anode to exhibit long-term cyclic life(701 mA h g^(−1) afer 200 cycles at 0.1 A g^(−1))and high rate performance(497 and 390 mA h g^(−1) at 1 and 2 A g^(−1),respectively).Tis work provides a new perspective towards chemically binding scafolded low-cost electrode and electrocatalyst materials with 3D graphene architectures for boosting energy storage and conversion.

关键词： anodic attached boosting

来源：评论

学校读者我要写书评

暂无评论

Topological phonons in an inhomogeneously strained silicon-1: Evidence of long-distance spin transport and unidirectional magnetoresistance of phonons

arXiv

引用

arXiv 2021年

作者： Katailiha, Anand Bhardwaj, Ravindra G. Lou, Paul C. Beyermann, Ward P. Kumar, Sandeep Department of Mechanical engineering University of California RiversideCA92521 United States Department of Physics and Astronomy University of California RiversideCA92521 United States Materials Science and Engineering Program University of California RiversideCA92521 United States

Transverse acoustic waves in an inhomogeneous medium are analogues to electromagnetic waves and will exhibit topological behavior due to the Berry gauge potential in the momentum space due to inhomogeneity. The inhomogeneous (or gradient) medium can be created using an applied strain gradient in a semiconductor thin film (silicon) since the phonon frequency and dispersion will be a function of the local strain along the strain gradient direction. As a consequence, topological phonon mediated spin and heat transport can be engineered in the semiconductor thin films. Here, we present evidence of a long-distance (100 µm) spin transport in the freestanding Si thin film sample under an applied strain gradient using transverse spin-Nernst effect measurement. The long-distance spin transport was attributed to the topological spin-Hall effect of phonons in an inhomogeneous medium. The inhomogeneous medium was validated using unidirectional magnetoresistance of phonons where the magnitude of the coefficient of the non-reciprocal response at room temperature was as large as reported in the BiTeBr at low temperatures. The topological phonons also manifested the topological Nernst effect. This work not only enhances the current understanding of inhomogeneous systems but also lays the foundation of the topological and spin phononics. © 2021, CC BY.

关键词： Phonons

来源：评论

学校读者我要写书评

暂无评论

A Human-Centered Design Approach to SOVTE Straw Phonation Instruction

引用

Journal of Voice 2023年

作者： Bhatt, Sandeep Scearce, Leda Frank-Ito, Dennis Nixon, Tara Umstead, Kelly A. Department of Industrial Design North Carolina State University Raleigh NC United States Department of Head and Neck Surgery & Communication Sciences Duke University School of Medicine Durham NC United States Computational Biology and Bioinformatics Program Duke University Durham NC United States Department of Mechanical Engineering and Materials Science Duke University Durham NC United States

Objectives: Extensive research has demonstrated that straw/tube phonation exercises produce positive effects on the voice quality of the user. The purpose of this study was to explore pedagogical practices employed by a range of voice professionals when using SOVTEs by applying human-centered design approaches to examine workflow and communication between teachers and students. Method/Design: The researchers conducted a series of five participatory role-playing workshop activities at a multi-disciplinary vocology conference that included speech-language pathologists, voice scientists, physicians, singing teachers, acting voice teachers, choral directors, and singers. Volunteers were asked to assume the role of teaching or learning straw phonation exercises. The other participants from each workshop were asked to provide written and verbal feedback regarding the teacher/student dynamics and what they found most important and relevant in terms of best practices for SOVTEs. Expert evaluators subsequently provided similar feedback based on video recordings of the workshops. Results: While there was variability noted in teaching techniques and results, common themes emerged in the analysis. Successful and unsuccessful student and teacher techniques were identified by the workshop participants. Through the video analysis, the research team identified themes in instructional teaching, experiential learning, and straw articulation and mechanics. Conclusions: The benefits of straw/tube phonation exercises on voice quality have been well-established and are clear. As we continue to refine best practices in SOVTEs and, in particular, straw phonation, involvement of experts in HCD as part of multidisciplinary teams may lead to the eventual design of SOVTE tools that provide greater precision, consistency, and effectiveness both in clinical and pedagogical settings, and aid in the differentiation of SOVTE approaches within the taxonomy of vocal habilitation and rehabilitation te

关键词： Voice disorder Voice habilitation Voice pedagogy Voice rehabilitation Voice therapy Voice training

来源：评论

学校读者我要写书评

暂无评论

Lattice Transformation from 2-D to Quasi 1-D and Phonon Properties of Exfoliated ZrS2 and ZrSe2

arXiv

引用

arXiv 2022年

作者： Alsulami, Awsaf Alharbi, Majed Alsaffar, Fadhel Alolaiyan, Olaiyan Aljalham, Ghadeer Albawardi, Shahad Alsaggaf, Sarah Alamri, Faisal Tabbakh, Thamer A. Amer, Moh R. Center of Excellence for Green Nanotechnologies Joint Centers of Excellence Program King Abdulaziz City for Science and Technology Riyadh Saudi Arabia Department of Mechanical and Aerospace Engineering University of California Los Angeles Los AngelesCA90095 United States National Center for Nanotechnology Materials Science Institute King Abdulaziz City for Science and Technology Riyadh Saudi Arabia Department of Electrical and Computer Engineering University of California Los Angeles Los AngelesCA90095 United States

Recent reports on thermal and thermoelectric properties of emerging 2-Dimensional (2D) materials have shown promising results. Yet, most of these emerging materials are underrepresented or lack a consistent and thorough investigation. Among these materials are Zirconium based chalcogenides such as Zirconium Disulfide (ZrS2) and Zirconium Dieselenide (ZrSe2). Here, we investigate the thermal properties of these Zirconium based materials using confocal Raman spectroscopy. We observed 2 different and distinctive Raman signatures for exfoliated ZrX2 (where X = S or Se). These Raman modes generally depend on the shape of the exfoliated nanosheets, regardless of the incident laser polarization. These 2 shapes are divided into 2D- ZrX2 and quasi 1D- ZrX2. For 2D- ZrX2, Raman modes are in alignment with those reported in literature. However, for quasi 1D-ZrX2, we show that Raman modes are identical to exfoliated ZrX3 nanosheets, indicating a major lattice transformation from 2D to quasi-1D. We also measure thermal properties of each resonant Raman mode for each ZrX2 shape. Based on our measurements, most Raman modes exhibit a linear downshift dependence with temperature. However, for ZrS2, we see an upshift (blueshift) with temperature for A1g mode, which is attributed to non-harmonic effects caused by dipolar coupling with IR-active modes. Moreover, the observed temperature dependence coefficient for some phonon modes of quasi 1D-ZrX2 differ dramatically, which can be caused by the quasi 1D lattice. Finally, we measure phonon dynamics under optical heating for each of 2D-ZrX2 and quasi 1D-ZrX2 and show phonon confinement in quasi 1D-ZrX2 nanosheets. We extract the thermal conductivity and the interfacial thermal conductance for each of 2D-ZrX2 and quasi 1D-ZrX2 nanosheets. Our calculations indicate lower interfacial thermal conductance for quasi 1D-ZrX2 compared to 2D-ZrX2, which can be attributed to the phonon confinement in 1D. Based on our model, we show low thermal con

关键词： Thermal conductivity

来源：评论

学校读者我要写书评

暂无评论

Pulverizing Fe₂O₃ Nanoparticles for Developing Fe₃C/N-Codoped Carbon Nanoboxes with Multiple Polysulfide Anchoring and Converting Activity in Li-S Batteries

引用

Advanced Functional materials 2021年第18期31卷 2011249-2011249页

作者： Zhou, Changyu Li, Xiangcun Jiang, Helong Ding, Yu He, Gaohong Guo, Jiao Chu, Zhong Yu, Guihua State Key Laboratory of Fine Chemicals Chemical Engineering Department Dalian University of Technology Dalian 116024 China Materials Science and Engineering Program and Department of Mechanical Engineering The University of Texas at Austin Austin 78712 TX United States

Sluggish redox kinetics, shuttle effect, poor conductivity, and large volume change of sulfur limit the practical applications of lithium-sulfur batteries. Hollow, porous, and necklace-like Fe₃C/N-codoped carbon nanoboxes (Fe₃C/NC) connected by N-doped carbon (NC) nanofibers are designed by pulverizing Fe₂O₃ embedded in polyacrylonitrile (PAN) fibers to produce multifunctional sulfur hosts, which exhibit multiple polysulfide anchoring and catalytic conversion activities. Experimental and first-principles density functional theory studies reveal that the uniformly distributed Fe₃C and N units in the nanoboxes can significantly suppress the polysulfide shuttle effect. The conversion of polysulfides (LiPSs) to Li₂S is catalyzed during discharge. The process relies on the fast electron transfer through the NC nanofibers and facilitated Li⁺ diffusion through the porous nanobox shells. The structural characteristics (“boxes in fibers”) of the nanoboxes influence the high sulfur loading and tolerance of volume variation of LiPSs, resulting in the synergistic catalysis of the redox reactions. A high capacity of 645 mAh g⁻¹ after 240 cycles at 1 C, a high capacity of 712 mAh g⁻¹ at a high sulfur loading of 5 mg cm⁻² after 100 cycles at 0.2 C, and an enhanced areal capacity of 3.6 mAh cm⁻² are demonstrated. © 2021 Wiley-VCH GmbH.

关键词： Fe 3C fibers Li-S batteries membranes nanoboxes

来源：评论

学校读者我要写书评

暂无评论

A comparative study of the structural and optoelectronic properties of Al- and Ga-doped ZnO films deposited by atmospheric pressure plasma jet

引用

Journal of Alloys and Compounds 2025年 1031卷

作者： Chou, Chih-Yun Chiu, Po-Han Chao, Yin-Chun Yen, Hung-Wei Juang, Jia-Yang Program in Nanoengineering and Nanoscience Graduate School of Advanced Technology National Taiwan University Taipei106319 Taiwan Department of Materials Science and Engineering National Taiwan University Taipei106319 Taiwan Department of Mechanical Engineering National Taiwan University Taipei106319 Taiwan

The high cost of gallium has driven interest in aluminum-doped zinc oxide (AZO) as a cost-effective alternative to gallium-doped zinc oxide (GZO). While prior studies have primarily focused on sputtering methods to compare AZO and GZO, research on non-sputtering techniques remains limited. Our previous works demonstrated favorable optoelectronic properties in GZO films deposited via atmospheric pressure plasma jet (APPJ);however, APPJ-deposited AZO has yet to be explored. In this study, we compare AZO and GZO thin films fabricated by APPJ under ambient conditions. We find that the deposition rate of AZO is approximately twice that of GZO under the same processing parameters, due to differences in droplet size from the ultrasonic generator. By adjusting precursor delivery and working distance (the nozzle-to-substrate gap), we can tune film thickness, morphology, and optoelectronic properties, showcasing APPJ's versatility over sputtering. Despite similar precursor concentrations and film thickness, AZO films exhibit lower carrier concentration (∼1 ×1020 cm–3) and mobility (∼7.5 cm2/Vs) than GZO (∼8 ×1020 cm–3 and ∼15 cm²/Vs), attributed to reduced aluminum incorporation (∼0.4 at% vs. ∼2.2 at% in GZO). Reducing the working distance from 2 mm to 1.5 mm improves both films’ structural integrity and optoelectronic performance (figure of merit increases by 140 % for GZO and 100 % for AZO). However, AZO remains inferior to GZO, highlighting the need for further optimization. © 2025 Elsevier B.V.

关键词： Transparent conducting oxides

来源：评论

学校读者我要写书评

暂无评论

In Situ Atomic-Scale Visualization of Oxygen Vacancy Assisted Reaction Dynamics on TiO2Surfaces

引用

Microscopy and Microanalysis 2024年第SUPPLEMENT_1期30卷

作者： Chen, Xiaobo Li, Meng Hwang, Sooyeon Zakharov, Dmitri N Yang, Judith Zhou, Guangwen Materials Science and Engineering Program & Department of Mechanical Engineering State University of New York at Binghamton Binghamton New York United States Center for Functional Nanomaterials Brookhaven National Laboratory Upton New York United States

来源：评论

学校读者我要写书评

暂无评论

Decarbonization of aviation via hydrogen propulsion: technology performance targets and energy system impacts

arXiv

引用

arXiv 2023年

作者： Cybulsky, Anna Allroggen, Florian Shao-Horn, Yang Mallapragada, Dharik S. MIT Energy Initiative Massachusetts Institute of Technology CambridgeMA02139 United States Laboratory for Aviation and the Environment Department of Aeronautics and Astronautics Massachusetts Institute of Technology CambridgeMA02139 United States Joint Program on the Science Policy of Global Change Massachusetts Institute of Technology CambridgeMA02139 United States Research Laboratory of Electronics Massachusetts Institute of Technology CambridgeMA02139 United States Department of Materials Science and Engineering Massachusetts Institute of Technology CambridgeMA02139 United States Department of Mechanical Engineering Massachusetts Institute of Technology CambridgeMA02139 United States

The aviation sector is challenging to decarbonize since aircraft require high power and energy per unit of weight. Liquid hydrogen is an interesting solution due to its high gravimetric energy density, minimal warming impact, and low-carbon production potential. We quantify the performance targets for fuel cell systems and on-board storage to enable hydrogen-powered regional aviation. We then explore the energy infrastructure impacts of meeting this additional H2 demand in the European context under deep decarbonization scenarios. We find that minimal payload reduction would be needed for powering regional aviation up to 1000 nmi if fuel cell system specific power of 2 kW/kg and tank gravimetric index of 50% can be achieved. The energy systems analysis highlights the importance of utilizing multiple technology options: such as nuclear expansion and natural gas reforming with CCS for hydrogen production. Levelized cost of liquid hydrogen as low as €3.5/kg demonstrates pathways for Europe to achieve cost-competitive production. Copyright © 2023, The Authors. All rights reserved.

关键词： Hydrogen storage

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：