A novel fiber-optic magnetic field sensor is demonstrated based on a dual-polarization fiber-grating laser, which is embedded in an epoxy resin-bonded magnetostrictive composite material with doped Terfenol-D particle...A novel fiber-optic magnetic field sensor is demonstrated based on a dual-polarization fiber-grating laser, which is embedded in an epoxy resin-bonded magnetostrictive composite material with doped Terfenol-D particles. A simple structure is designed to convert the magnetic field-induced strain to transversal stress, which is applied to the fiber laser to produce beat note frequency changes for measurement purposes. The response of the proposed sensor is measured, and shows quite a good directivity and linearity with a sensitivity of 10.5 Hz/μT to the magnetic field. It also shows a large measurable range up to about 0.3 T.展开更多
Magnetic feld sensing plays an important role in many felds of scientifc research and engineering applications.Benefting from the advantages of optical fbers,the optical fber-based magnetic feld sensors demonstrate ch...Magnetic feld sensing plays an important role in many felds of scientifc research and engineering applications.Benefting from the advantages of optical fbers,the optical fber-based magnetic feld sensors demonstrate characteristics of light weight,small size,remote controllability,reliable security,and wide dynamic ranges.This paper provides an overview of the basic principles,development,and applications of optical fber magnetic feld sensors.The sensing mechanisms of fber grating,interferometric and evanescent feld fber are discussed in detail.Magnetic fuid materials,magneto-strictive materials,and magneto-optical materials used in optical fber sensing systems are also introduced.The applications of optical fber magnetic feld sensors as current sensors,geomagnetic monitoring,and quasi-distributed magnetic sensors are presented.In addition,challenges and future development directions are analyzed.展开更多
As a typical contact-free manipulation technique that removes friction and contamination risk,levitation has gradually become a preferred candidate for various applications.Magnetic levitation using diamagnetism,beyon...As a typical contact-free manipulation technique that removes friction and contamination risk,levitation has gradually become a preferred candidate for various applications.Magnetic levitation using diamagnetism,beyond Earnshaw’s theorem,is a kind of passive stable levitation that can be achieved at normal temperatures with no energy input.Appealingly,most seemingly nonmagnetic materials can be levitated in a magnetic field and can stabilize free levitation of magnetic materials.This review focuses on the fundamental principles of magnetic levitation using diamagnetism,with emphasis on its burgeoning applications.The theoretical basis associated with the magnetic levitation using diamagnetism is discussed by elucidating the characteristics of diamagnetic materials,and the key levitation mechanisms are clarified.Afterwards,state-of-the-art applications in various aspects,including sensing and measurement,actuating and micromanipulation,energy harvesting and magnetic gravity compensation,are summarized and compared.Finally,the review concludes with a brief outlook on future perspectives.展开更多
Serum biomarkers in the form of proteins （e.g. cluster of differentiation-44 （CD44）） have been demonstrated to have high clinical sensitivity and specificity for disease diagnosis and prognosis. Owing to the high ...Serum biomarkers in the form of proteins （e.g. cluster of differentiation-44 （CD44）） have been demonstrated to have high clinical sensitivity and specificity for disease diagnosis and prognosis. Owing to the high sample complexity and low molecular abundance in serum, the detection and profiling of biomarkers rely on efficient extraction by materials and devices, mostly using immunoassays via antibody-antigen recognition. Antibody-free approaches are promising and need to be developed for real-case applications in serum to address the limitations of antibody-based techniques in terms of robustness, expense, and throughput. In this work, we demonstrated a novel approach using hyaluronic acid （HA）-modified materials/devices for the extraction, detection, and profiling of serum biomarkers via ligand-protein interactions. We constructed Fe304@SiOa@HA particles with different sizes through layer-by-layer assembly and for the first time applied HA-functionalized particles in the facile extraction and sequence identification of CD44 in serum by mass spectrometry. We also first validated HA-CD44 binding through electrochemical sensing using HA- modified electrodes in both standard solutions and diluted serum samples, achieving a detection limit of -0.6 ng/mL and a linear response range from I ng/mL to 10 ~tg/mL. Furthermore, we performed profiling of HA-binding serum proteome, providing a new preliminary benchmark for the construction of future databases, and we investigated selected surface chemistries of particles for the capture of proteins in serum. Our work not only resulted in the development of a platform technology for CD44 extraction/detection and HA-binding proteome identification, but also guided the design of ligand affinity-based approaches for antibody-free analysis of serum biomarkers towards diagnostic applications.展开更多
An algorithm is presented for multi-sensor image fusion using discrete wavelet frame transform (DWFT). The source images to be fused are firstly decomposed by DWFT. The fusion process is realized by combining the sour...An algorithm is presented for multi-sensor image fusion using discrete wavelet frame transform (DWFT). The source images to be fused are firstly decomposed by DWFT. The fusion process is realized by combining the source coefficients. Before the image fusion process, image segmentation is performed on each source image in order to obtain the region representation of each source image. For each source image, the salience of each region in its region representation is calculated. By overlapping all these region representations of all the source images, we produce a shared region representation to label all the input images. The fusion process is guided by these region representations. Region match measure of the source images is calculated for each region in the shared region representation. When fusing the similar regions, weighted averaging mode is performed; otherwise selection mode is performed. Experimental results using real data show that the proposed algorithm outperforms the traditional pyramid transform based or discrete wavelet transform (DWT) based algorithms in multi-sensor image fusion.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.11474133 and61235005)the Planned Science and Technology Project of Guangzhou(Grant No.2012J5100028)the Project of Science and Technology New Star of Zhujiang in Guangzhou City(Grant No.2012J2200043)
文摘A novel fiber-optic magnetic field sensor is demonstrated based on a dual-polarization fiber-grating laser, which is embedded in an epoxy resin-bonded magnetostrictive composite material with doped Terfenol-D particles. A simple structure is designed to convert the magnetic field-induced strain to transversal stress, which is applied to the fiber laser to produce beat note frequency changes for measurement purposes. The response of the proposed sensor is measured, and shows quite a good directivity and linearity with a sensitivity of 10.5 Hz/μT to the magnetic field. It also shows a large measurable range up to about 0.3 T.
基金supported by Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan)(No.162301212322)the National Natural Science Foundation of China(Grant No.62005255).
文摘Magnetic feld sensing plays an important role in many felds of scientifc research and engineering applications.Benefting from the advantages of optical fbers,the optical fber-based magnetic feld sensors demonstrate characteristics of light weight,small size,remote controllability,reliable security,and wide dynamic ranges.This paper provides an overview of the basic principles,development,and applications of optical fber magnetic feld sensors.The sensing mechanisms of fber grating,interferometric and evanescent feld fber are discussed in detail.Magnetic fuid materials,magneto-strictive materials,and magneto-optical materials used in optical fber sensing systems are also introduced.The applications of optical fber magnetic feld sensors as current sensors,geomagnetic monitoring,and quasi-distributed magnetic sensors are presented.In addition,challenges and future development directions are analyzed.
基金supported by the Innovation Program of Shanghai Municipal Education Commission(Grant No.2019-01-07-00-02-E00030)the National Science Fund for Distinguished Young Scholars(Grant No.11625208)the Program of Shanghai Academic/Technology Research Leader(Grant No.19XD1421600)。
文摘As a typical contact-free manipulation technique that removes friction and contamination risk,levitation has gradually become a preferred candidate for various applications.Magnetic levitation using diamagnetism,beyond Earnshaw’s theorem,is a kind of passive stable levitation that can be achieved at normal temperatures with no energy input.Appealingly,most seemingly nonmagnetic materials can be levitated in a magnetic field and can stabilize free levitation of magnetic materials.This review focuses on the fundamental principles of magnetic levitation using diamagnetism,with emphasis on its burgeoning applications.The theoretical basis associated with the magnetic levitation using diamagnetism is discussed by elucidating the characteristics of diamagnetic materials,and the key levitation mechanisms are clarified.Afterwards,state-of-the-art applications in various aspects,including sensing and measurement,actuating and micromanipulation,energy harvesting and magnetic gravity compensation,are summarized and compared.Finally,the review concludes with a brief outlook on future perspectives.
文摘Serum biomarkers in the form of proteins （e.g. cluster of differentiation-44 （CD44）） have been demonstrated to have high clinical sensitivity and specificity for disease diagnosis and prognosis. Owing to the high sample complexity and low molecular abundance in serum, the detection and profiling of biomarkers rely on efficient extraction by materials and devices, mostly using immunoassays via antibody-antigen recognition. Antibody-free approaches are promising and need to be developed for real-case applications in serum to address the limitations of antibody-based techniques in terms of robustness, expense, and throughput. In this work, we demonstrated a novel approach using hyaluronic acid （HA）-modified materials/devices for the extraction, detection, and profiling of serum biomarkers via ligand-protein interactions. We constructed Fe304@SiOa@HA particles with different sizes through layer-by-layer assembly and for the first time applied HA-functionalized particles in the facile extraction and sequence identification of CD44 in serum by mass spectrometry. We also first validated HA-CD44 binding through electrochemical sensing using HA- modified electrodes in both standard solutions and diluted serum samples, achieving a detection limit of -0.6 ng/mL and a linear response range from I ng/mL to 10 ~tg/mL. Furthermore, we performed profiling of HA-binding serum proteome, providing a new preliminary benchmark for the construction of future databases, and we investigated selected surface chemistries of particles for the capture of proteins in serum. Our work not only resulted in the development of a platform technology for CD44 extraction/detection and HA-binding proteome identification, but also guided the design of ligand affinity-based approaches for antibody-free analysis of serum biomarkers towards diagnostic applications.
基金This work was jointly supported by the National '863' Program of China (No. 2001AA135091) National Natural Science Foundation of China (No. 60375008)+1 种基金 Shanghai Key Scientific Project (No. 02DZ15001) China Ph.D Discipline Special Foundation (No. 2002
文摘An algorithm is presented for multi-sensor image fusion using discrete wavelet frame transform (DWFT). The source images to be fused are firstly decomposed by DWFT. The fusion process is realized by combining the source coefficients. Before the image fusion process, image segmentation is performed on each source image in order to obtain the region representation of each source image. For each source image, the salience of each region in its region representation is calculated. By overlapping all these region representations of all the source images, we produce a shared region representation to label all the input images. The fusion process is guided by these region representations. Region match measure of the source images is calculated for each region in the shared region representation. When fusing the similar regions, weighted averaging mode is performed; otherwise selection mode is performed. Experimental results using real data show that the proposed algorithm outperforms the traditional pyramid transform based or discrete wavelet transform (DWT) based algorithms in multi-sensor image fusion.
