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Underwater acoustic metamaterials

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National Science Review 2023年第6期10卷 258-280页

作者： Erqian Dong Peizheng Cao Jinhu Zhang Sai Zhang nicholas X.fang Yu Zhang Key Laboratory of Underwater Acoustic Communication and Marine Information Technology of the Ministry of Education College of Ocean and Earth Sciences Xiamen University State Key Laboratory of Marine Environmental Science Xiamen University School of Physics and Electronic Engineering Jiangsu University Department of Mechanical Engineering Massachusetts Institute of Technology

Acoustic metamaterials have been widely investigated over the past few decades and have realized acoustic parameters that are not achievable using conventional *** demonstrating that locally resonant acoustic metamaterials are capable of acting as subwavelength unit cells,researchers have evaluated the possibility of breaking the classical limitations of the material mass density and bulk *** with theoretical analysis,additive manufacturing and engineering applications,acoustic metamaterials have demonstrated extraordinary capabilities,including negative refraction,cloaking,beam formation and super-resolution *** to the complexity of impedance boundaries and mode transitions,there are still challenges in freely manipulating acoustic propagation in an underwater *** review summarizes the developments in underwater acoustic metamaterials over the past 20 years,which include underwater acoustic invisibility cloaking,underwater beam formation,underwater metasurfaces and phase engineering,underwater topological acoustics and underwater acoustic metamaterial *** the evolution of underwater metamaterials and the timeline of scientific advances,underwater acoustic metamaterials have demonstrated exciting applications in underwater resource development,target recognition,imaging,noise reduction,navigation and communication.

关键词： underwater acoustic metamaterials invisibility cloaking beam formation topological acoustics metasurfaces absorbers

Physical modeling and validation of porpoises' directional emission via hybrid metamaterials

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National Science Review 2019年第5期6卷 921-928页

作者： Erqian Dong Yu Zhang Zhongchang Song Tianye Zhang Chen Cai nicholas X.fang Key Laboratory of Underwater Acoustic Communication and Marine Information Technology of the Ministry of Education College of Ocean and Earth SciencesXiamen University Department of Mechanical Engineering Massachusetts Institute of Technology State Key Laboratory of Marine Environmental Science Xiamen University Biology Department Woods Hole Oceanographic Institution

In wave physics and engineering, directional emission sets a fundamental limitation on conventional simple sources as their sizes should be sufficiently larger than their *** metamaterial and animal biosonar both show potential in overcoming this *** metamaterials arranged in periodic microstructures face great challenges in realizing complex and multiphase biosonar ***, we proposed a physical directional emission model to bridge the gap between porpoises’ biosonar and artificial *** by the anatomical and physical properties of the porpoise’s biosonar transmission system, we fabricated a hybrid metamaterial system composed of multiple composite *** validated that the hybrid metamaterial significantly increased directivity and main lobe energy over a broad bandwidth both numerically and *** device displayed efficiency in detecting underwater target and suppressing false target *** metamaterial-based physical model may be helpful to achieve the physical mechanisms of porpoise biosonar detection and has diverse applications in underwater acoustic sensing, ultrasound scanning, and medical ultrasonography.

关键词： porpoise’s physical model metamaterials biosonar directional emission

Breaking the barriers: advances in acoustic functional materials

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National Science Review 2018年第2期5卷 159-182页

作者： Hao Ge Min Yang Chu Ma Ming-Hui Lu Yan-Feng Chen nicholas fang Ping Sheng National Laboratory of Solid State Microstructures and Department of Materials Science and Engineering College of Engineering and Applied SciencesNanjing University Department of Physics Hong Kong University of Science and Technology Department of Mechanical Engineering Massachusetts Institute of Technology Collaborative Innovation Center of Advanced Microstructures Nanjing University

Acoustics is a classical field of study that has witnessed tremendous developments over the past 25 *** by the novel acoustic effects underpinned by phononic crystals with periodic modulation of elastic building blocks in wavelength scale and acoustic metamaterials with localized resonant units in subwavelength scale, researchers in diverse disciplines of physics, mathematics, and engineering have pushed the boundary of possibilities beyond those long held as unbreakable limits. More recently, structure designs guided by the physics of graphene and topological electronic states of matter have further broadened the whole field of acoustic metamaterials by phenomena that reproduce the quantum effects classically. Use of active energy-gain components, directed by the parity–time reversal symmetry principle,has led to some previously unexpected wave characteristics. It is the intention of this review to trace historically these exciting developments, substantiated by brief accounts of the salient milestones. The latter can include, but are not limited to, zero/negative refraction, subwavelength imaging, sound cloaking, total sound absorption, metasurface and phase engineering, Dirac physics and topology-inspired acoustic engineering, non-Hermitian parity–time synthetic active metamaterials, and one-way propagation of sound waves. These developments may underpin the next generation of acoustic materials and devices, and offer new methods for sound manipulation, leading to exciting applications in noise reduction, imaging, sensing and navigation, as well as communications.

关键词： acoustic metamaterials phononic crystals topological acoustics PT-symmetry synthetic acoustics sound absorption

Projection micro stereolithography based 3D printing and its applications

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International Journal of Extreme Manufacturing 2020年第2期2卷 68-86页

作者： Qi Ge Zhiqin Li Zhaolong Wang Kavin Kowsari Wang Zhang Xiangnan He Jianlin Zhou nicholas X fang Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055GuangdongPeople’s Republic of China BMF Material Technology Inc. Shenzhen 518110ShenzhenPeople’s Republic of China State-Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082HunanPeople’s Republic of China Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMA 02139-4307United States of America Digital Manufacturing and Design Centre Singapore University of Technology and Design487372Singapore

Projection micro stereolithography(PμSL)is a high-resolution(up to 0.6μm)3D printing technology based on area projection triggered photopolymerization,and capable of fabricating complex 3D architectures covering multiple scales and with multiple *** paper reviews the recent development of the PμSL based 3D printing technologies,together with the related *** introduces the working principle,the commercialized products,and the recent multiscale,multimaterial printing capability of PμSL as well as some functional photopolymers that are suitable to Pμ*** review paper also summarizes a few typical applications of PμSL including mechanical metamaterials,optical components,4D printing,bioinspired materials and biomedical applications,and offers perspectives on the directions of the further development of PμSL based 3D printing technology.

关键词： projection microstereolithography multiscale 3D printing multimaterial 3D printing

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Muscle-fiber array inspired, multiple-mode, pneumatic artificial muscles through planar design and one-step rolling fabrication

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National Science Review 2021年第10期8卷 68-78页

作者： Jiang Zou Miao Feng Ningyuan Ding Peinan Yan Haipeng Xu Dezhi Yang nicholas X.fang Guoying Gu Xiangyang Zhu State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Department of Mechanical Engineering Massachusetts Institute of Technology Robotics Institute School of Mechanical Engineering Shanghai Jiao Tong University

Advances in development of artificial muscles have enabled creation of soft robots with biological dexterity and self-adaption in unstructured environments; however, production of scalable artificial muscles with multiple-mode actuations remains elusive. Inspired by muscle-fiber arrays in muscular hydrostats, we present a class of versatile artificial muscles called MAIPAMs(muscle-fiber array inspired pneumatic artificial muscles), capable of multiple-mode actuations(such as parallel elongation-bending-spiraling actuations, 10 parallel bending actuations and cascaded elongation-bending-spiraling actuations). Our MAIPAMs consist of active 3 D elastomer-balloon arrays reinforced by a passive elastomer membrane,achieved through a planar design and one-step rolling fabrication approach. We introduce prototypical designs for the MAIPAMs and demonstrate their muscle-mimic structures and versatility, as well as their scalable ability to integrate flexible but non-stretchable layers for contraction and twisting actuation modes and compliant electrodes for self-sensing. We further demonstrate that this class of artificial muscles shows potential for versatile robotic applications, such as carrying a camera for recording videos, gripping or manipulating objects, and climbing a pipe-line.

关键词： soft robotics pneumatic artificial muscles multiple-mode actuations bio-inspired design

3D direct printing of mechanical and biocompatible hydrogel meta-structures

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Bioactive Materials 2022年第4期7卷 48-55页

作者： Lei Zhang Wenhan Lee Xinhao Li Yanhui Jiang nicholas Xuanlai fang Guohao Dai Yongmin Liu Department of Mechanical&Industrial Engineering Northeastern UniversityBostonMA02115United States State Key Laboratory of Primate Biomedical Research Institute of Primate Translational MedicineKunming University of Science and TechnologyKunming650500China Department of Bioengineering Northeastern UniversityBostonMA02115United States Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMA02139United States Department of Electrical and Computer Engineering Northeastern UniversityBostonMA02115United States

Direct Ink Writing(DIW)has demonstrated great potential as a versatile method to 3D print multifunctional *** this work,we report the implementation of hydrogel meta-structures using DIW at room temperature,which seamlessly integrate large specific surface areas,interconnected porous characteristics,mechanical toughness,biocompatibility,and water absorption and retention *** but hydrophobic polymers and weakly crosslinked nature-origin hydrogels form a balance in the self-supporting ink,allowing us to directly print complex meta-structures without sacrificial materials and heating ***,the mixed bending or stretching of symmetrical re-entrant cellular lattices and the unique curvature patterns are combined to provide little lateral expansion and large compressive energy absorbance when external forces are applied on the printed *** addition,we have successfully demonstrated ear,aortic valve conduits and hierarchical *** anticipate that the reported 3D meta-structured hydrogel would offer a new strategy to develop functional biomaterials for tissue engineering applications in the future.

关键词： Direct ink writing Gyroid meta-structure Mechanical-functional integration Naturally derived hydrogel

HDPairFinder:A data processing platform for hydrogen/deuterium isotopic labeling-based nontargeted analysis of trace-level amino-containing chemicals in environmental water

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Journal of Environmental Sciences 2024年第2期136卷 583-593页

作者： Tingting Zhao Kristin Carroll Caley B.Craven nicholas J.P.Wawryk Shipei Xing Jian Guo Xing-fang Li Tao Huan Department of Chemistry Faculty of ScienceUniversity of British ColumbiaVancouver Campus2036 Main MallVancouverBritish ColumbiaV6T 1Z1Canada Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyFaculty of Medicine and DentistryUniversity of AlbertaEdmontonAlberta T6G 2G3Canada

The combination of hydrogen/deuterium(H/D)formaldehyde-based isotopic methyl labeling with solid-phase extraction and high-performance liquid chromatography–high resolution mass spectrometry(HPLC-HRMS)is a powerful analytical solution for nontargeted analysis of trace-level amino-containing chemicals in water *** the huge amount of chemical information generated in HPLC-HRMS analysis,identifying all possible H/Dlabeled amino chemicals presents a significant challenge in data *** address this,we designed a streamlined data processing pipeline that can automatically extract H/D-labeled amino chemicals from the raw HPLC-HRMS data with high accuracy and ***,we developed a cross-correlation algorithm to correct the retention time shift resulting from deuterium isotopic effects,which enables reliable pairing of H-and D-labeled ***,we implemented several bioinformatic solutions to remove false chemical features generated by in-source fragmentation,salt adduction,and natural13C ***,we used a data mining strategy to construct the AMINES library that consists of over 38,000 structure-disjointed primary and secondary amines to facilitate putative compound ***,we integrated these modules into a freely available R program,*** rationale of each module was justified and its performance tested using experimental H/D-labeled chemical standards and authentic water *** further demonstrated the application of HDPairFinder to effectively extract N-containing contaminants,thus enabling the monitoring of changes of primary and secondary N-compounds in authentic water *** is a reliable bioinformatic tool for rapid processing of H/D isotopic methyl labeling-based nontargeted analysis of water samples,and will facilitate a better understanding of N-containing chemical compounds in water.

关键词： Isotope labeling Nontargeted analysis Reactive N-compounds HPLC-HRMS Source water

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Additive manufacturing of high aspect-ratio structures with self-focusing photopolymerization

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Light(Advanced Manufacturing) 2022年第3期3卷 120-149页

作者： Mingyu Yang Kavin Kowsari Nia O.Myrie Daniela Espinosa-Hoyos Anna Jagielska Seok Kim nicholas X.fang Krystyn J.Van Vliet Harvard-MIT Health Sciences and Technology Massachusetts Institute of TechnologyCambridgeMA02139United States Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMA02139United States Department of Radiology Brigham and Women’s HospitalHarvard Medical SchoolBostonMA02115United States Department of Biological Engineering Massachusetts Institute of TechnologyCambridgeMA02139United States Walter H.Coulter Department of Biomedical Engineering Georgia Institute of Technology and Emory University School of MedicineAtlantaGA30332United States Department of Chemical Engineering Massachusetts Institute of TechnologyCambridgeMA02139United States Department of Materials Science&Engineering Massachusetts Institute of TechnologyCambridgeMA02139United States Department of Mechanical Engineering Changwon National UniversityChangwon51140South Korea

Photocrosslinkable polymers have been exploited to attain impressive advantages in printing freestanding,micrometer-scale,mechanically compliant ***,a more integrated understanding of both the polymer photochemistry and the microfabrication processes could enable new strategic design avenues,unlocking far-reaching applications of the light-based modality of additive *** promising approach for achieving high-aspect-ratio structures is to leverage the phenomenon of light self-trapping during the photopolymerization *** this review,we discuss the design of materials that facilitate this optical behavior,the computational modeling and practical processing considerations to achieve high aspect-ratio structures,and the range of applications that can benefit from architectures fabricated using light self-trapping-especially those demanding free-standing structures and materials of stiffnesses relevant in biological *** interactions exist among material attributes,including polymer composition,and processing parameters such as light *** identify strong opportunities for predictive design of both the material and the ***,this perspective describes the wide range of existing polymers and additive manufacturing approaches,and highlights various future directions to enable constructs with new complexities and functionalities through the development of next-generation photocrosslinkable materials and micromanufacturing methods.

关键词： Additive manufacturing Optical waveguide High aspect-ratio Biocompatible structures Polymer photochemistry

Integration of solid phase extraction with HILIC-MS/MS for analysis of free amino acids in source water

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Journal of Environmental Sciences 2022年第7期34卷 190-196页

作者： Junlang Qiu Caley Craven nicholas Wawryk Kristin Carroll Xing-fang Li Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyUniversity of AlbertaEdmontonT6G 2G3Canada School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510006China

Amino acids(AAs) are prevalent in source water, particularly during spring run-off. Monitoring of amino acids in source water is desirable for water treatment plants(WTP) to indicate changes in source water quality. The objective of this study was to establish analytical procedures for reliable monitoring of amino acids in source water. Therefore, we examined two different methods, large volume inject(LVI) and solid phase extraction(SPE), for sample preparation prior to HILIC-MS/MS. The LVI-HILIC-MS/MS method can provide fast and sensitive detection for clean samples, but suffers from matrix effects, resulting in irreproducible separation and shortening column lifetime. We have demonstrated that SPE was necessary prior to HILIC-MS/MS to achieve reproducible and reliable quantification of AAs in source water. A natural heterocyclic amine 1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid(MTCCA) was also included in the method to indicate changes in other natural nitrogenous compounds in source water. The SPE-HILIC-MS/MS method was able to achieve limits of detection from 2.6-3400 ng/L for the amino acids and MTCCA with RSDs( n = 3) of 1.1%-4.8%. As well, retention times(RT) of the analytes were reproducible with variation less than 0.01 min( n = 3) through the entire project. We further applied the SPE-HILICMS/MS method to determine AAs in authentic source water samples collected from two drinking water treatment plants(WTPs) during the 2021 spring run-off season. The results support that the SPE-HILIC-MS/MS method does not require derivatization and can provide reliable, accurate, and robust analysis of AAs and MTCCA in source water, supporting future monitoring of source water quality.

关键词： Water analysis Disinfection byproducts Amino acids HPLC MS HILIC