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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

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

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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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

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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A General Synthesis Method for Covalent Organic Framework and Inorganic 2D Materials Hybrids

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Precision Chemistry 2024年第8期2卷 398-405页

作者： Yifan Zhu Yunrui Yan Yuren Feng Yifeng Liu Chen-Yang Lin Qing Ai Tianshu Zhai Bongki Shin Rui xu Hongchen Shen Qiyi fang xiang Zhang Dayanni Bhagwandin Yimo Han Hanyu Zhu nicholas R.Glavin Pulickel M Ajayan Qilin Li Jun Lou Department of Materials Science and Nanoengineering Rice UniversityHoustonTexas 77005United States Department of Civil and Environmental Engineering Rice UniversityHoustonTexas 77005United States NSF Nanosystems Engineering Research Center Nanotechnology-Enabled Water Treatment Rice UniversityHoustonTexas 77005United States UES Inc.BeavercreekOhio 45432United States Materials and Manufacturing Directorate Air Force Research LaboratoryWright-Patterson AFBOhio 45433United States Department of Chemistry Rice UniversityHoustonTexas 77005United States

Two-dimensional(2D)inorganic/organic hybrids provide a versatile platform for diverse applications,including electronic,catalysis,and energy storage *** recent surge in 2D covalent organic frameworks(COFs)has introduced an organic counterpart for the development of advanced 2D organic/inorganic hybrids with improved electronic coupling,charge separation,and carrier ***,existing synthesis methods have primarily focused on few-layered film structures,which limits scalability for practical ***,we present a general synthesis approach for a range of COF/inorganic 2D material hybrids,utilizing 2D inorganic materials as both catalysts and inorganic building *** leveraging the intrinsic Lewis acid sites on the inorganic 2D materials such as hexagonal boron nitride(hBN)and transition metal dichalcogenides,COFs with diverse functional groups and topologies can grow on the surface of inorganic 2D *** controlled 2D morphology and excellent solution dispersibility of the resulting hybrids allow for easy processing into films through vacuum *** proof of concept,hBN/COF films were employed as filters for Rhodamine 6G removal under flow-through conditions,achieving a removal rate exceeding 93%.The present work provides a simple and versatile synthesis method for the scalable fabrication of COF/inorganic 2D hybrids,offering exciting opportunities for practical applications such as water treatment and energy storage.

关键词： Covalent organic frameworks Transition-metal dichalcogenides Lewis acid catalysts Hexagonal boron nitride Hybrid Materials

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

Pesticides and trace elements in cannabis:Analytical and environmental challenges and opportunities

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Journal of Environmental Sciences 2019年第11期31卷 82-93页

作者： Caley B.Craven nicholas Wawryk Ping Jiang Zhongshan Liu xing-fang Li Department of Chemistry Faculty of Science University of Alberta Edmonton AB T6G 2G2 Canada Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and Pathology Faculty of Medicine and DentistryUniversity of Alberta Edmonton AB T6G 2G3 Canada

Cannabis is increasingly used for both medicinal and recreational purposes with an estimate of over 180 million users *** has recently legalized cannabis use in October 2018,joining several states,in the United States of America (e.g.,Colorado,California,and Oregon) and a few other countries.A variety of cannabis products including dry flowers,edibles,and oil products are widely *** high demand for cannabis products worldwide,the quality of cannabis and its related products has become a major concern for consumer *** guidelines have been set by different countries to ensure the quality,safety,and efficacy of cannabis *** general,these guidelines require control of contaminants including pesticides,toxic elements,mycotoxins,and pathogens,as well as residual solvents in regard to cannabis ***,appropriate analytical methods are required to determine these contaminants in cannabis products for quality *** this review,we focus on the current analytical challenges and method development for detection of pesticides and toxic elements in cannabis to meet various guidelines.

关键词： Cannabis QA/QC Contaminants Analytical testing Pesticides Heavy metals Regulations

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