Acoustic-vortex(AV)tweezers ensure stable particle trapping at a zero-pressure center,while particle assembly between two vortex cores is still prevented by the high-potential barrier.Although a one-dimensional low-pr...Acoustic-vortex(AV)tweezers ensure stable particle trapping at a zero-pressure center,while particle assembly between two vortex cores is still prevented by the high-potential barrier.Although a one-dimensional low-pressure attractive path of particle assembly can be constructed by the interference between two independent cylindrical Bessel beams,it remains challenging to create two-dimensional(2D)neighboring vortexes using a source array in practical applications.In this paper,a three-step phase-reversal strategy of 2D particle assembly based on the synchronized evolution of a centrosymmetric array of M off-axis acoustic vortexes(OA-AVs)with a preset radial offset is proposed based on a ring array of planar sources.By introducing initial vortex phase differences of-2π/M and+2π/M to the vortex array,low-pressure patterns of an M-sided regular polygon and M-branched star are formed by connecting the vortex cores and the field center before and after the tangent state of adjacent OA-AVs.Center-oriented particle assembly is finally realized by a central AV constructed by coincident in-phase OA-AVs.The capability of particle manipulation in the lateral and radial directions is demonstrated by low-pressure patterns with acoustic radiation forces pointing to the field center during a synchronized central approach.The field evolution is certified by experimental field measurements for OA-AVs with different vo rtex numbers,initial vortex phase differences,and radial offsets using a ring array of 16 planar sources.The feasibility of particle assembly in two dimensions is also verified by the accurate manipulation of four particles using the low-pressure patterns of a four-sided polygon,a four-branched star,and a central AV in experiments.The three-step strategy paves a new way for 2D particle assembly based on the synchronize d evolution of centrosymmetric OA-AVs using a simplified single-sided source array,exhibiting excellent potential for the precise navigation and manipulation of cells and particles in biomedical applications.展开更多
What is the most favorite and original chemistry developed in your research group?Ring-opening polymerization-induced self-assembly of N-carboxyanhydrides(NCA-PISA),and fusion-induced particle assembly(FIPA).How do yo...What is the most favorite and original chemistry developed in your research group?Ring-opening polymerization-induced self-assembly of N-carboxyanhydrides(NCA-PISA),and fusion-induced particle assembly(FIPA).How do you get into this specific field?Could you please share some experiences with our readers?NCA-PISA was developed to solve the biodegradability problem of nanoparticles by traditional PISA,while FIPA was inspired by nature.展开更多
The fine-scale heterogeneity of granular material is characterized by its polydisperse microstructure with randomness and no periodicity. To predict the mechanical response of the material as the microstructure evolve...The fine-scale heterogeneity of granular material is characterized by its polydisperse microstructure with randomness and no periodicity. To predict the mechanical response of the material as the microstructure evolves, it is demonstrated to develop computational multiscale methods using discrete particle assembly-Cosserat continuum modeling in micro- and macro- scales,respectively. The computational homogenization method and the bridge scale method along the concurrent scale linking approach are briefly introduced. Based on the weak form of the Hu-Washizu variational principle, the mixed finite element procedure of gradient Cosserat continuum in the frame of the second-order homogenization scheme is developed. The meso-mechanically informed anisotropic damage of effective Cosserat continuum is characterized and identified and the microscopic mechanisms of macroscopic damage phenomenon are revealed. c 2013 The Chinese Society of Theoretical and Applied Mechanics. [doi: 10.1063/2.1301101]展开更多
Micrometer-sized Fe3O4 particles and nano-sized gold particles were first synthesized by methods of self-aggregation of surface-chemically modified Fe3O4 nanoparticles and citrate reduction of the Au3+to Au0,respectiv...Micrometer-sized Fe3O4 particles and nano-sized gold particles were first synthesized by methods of self-aggregation of surface-chemically modified Fe3O4 nanoparticles and citrate reduction of the Au3+to Au0,respectively.Interaction between these two types of particles resulted in the assembly of nano-sized gold particles on the surface of the micrometer-sized Fe3O4 particles,forming an assembled structure with the Fe3O4 core particles around which are attached nano-sized gold parti-cles.The Fe3O4/Au structure is named GoldMag particles with assembled structure.The synthetic process,structure,and magnetic property of the GoldMag particles were analyzed.GoldMag particles with assembled structure have an irregular shape,rough surface with a diameter of 2―3μm.These particles exhibit the superparamagnetic property with saturated magnetization of 41 A·m2/kg.In a single step,antibodies could be readily immobilized onto the surface of the particles with a high binding capacity.The GoldMag particles can be used as a novel carrier in immunoassays.The maximum quantity of human IgG immobilized onto GoldMag particles was 330μg/mg.In order to validate the quality of the GoldMag particles as immunoassay carriers,an immunoassay system was used.The relative amount of immobilized human IgG was measured by HRP-labeled anti human IgG.The coefficient of variation within parallel samples of each group was below 6%and the coefficient of variation of means between five groups carried out separately was below 7%.Based on the sandwich method,the Hepatitis B surface antigen(HBsAg)and interleukin-8(IL-8)were also analyzed by qualitative and quantitative detection,respectively.The result indicated that the GoldMag particles with assembled structure were an ideal carrier in immunoassay.展开更多
基金funded by the National Nature Science Foundation of China(11934009,12174198,and 12227808)the Natural Science Foundation of Jiangsu Province,China(BE2022814)+2 种基金the Universal Technology for Primary and Secondary Schoolsthe National Research Institute for Teaching Materialsthe Qing Lan Project of Jiangsu Province,China。
文摘Acoustic-vortex(AV)tweezers ensure stable particle trapping at a zero-pressure center,while particle assembly between two vortex cores is still prevented by the high-potential barrier.Although a one-dimensional low-pressure attractive path of particle assembly can be constructed by the interference between two independent cylindrical Bessel beams,it remains challenging to create two-dimensional(2D)neighboring vortexes using a source array in practical applications.In this paper,a three-step phase-reversal strategy of 2D particle assembly based on the synchronized evolution of a centrosymmetric array of M off-axis acoustic vortexes(OA-AVs)with a preset radial offset is proposed based on a ring array of planar sources.By introducing initial vortex phase differences of-2π/M and+2π/M to the vortex array,low-pressure patterns of an M-sided regular polygon and M-branched star are formed by connecting the vortex cores and the field center before and after the tangent state of adjacent OA-AVs.Center-oriented particle assembly is finally realized by a central AV constructed by coincident in-phase OA-AVs.The capability of particle manipulation in the lateral and radial directions is demonstrated by low-pressure patterns with acoustic radiation forces pointing to the field center during a synchronized central approach.The field evolution is certified by experimental field measurements for OA-AVs with different vo rtex numbers,initial vortex phase differences,and radial offsets using a ring array of 16 planar sources.The feasibility of particle assembly in two dimensions is also verified by the accurate manipulation of four particles using the low-pressure patterns of a four-sided polygon,a four-branched star,and a central AV in experiments.The three-step strategy paves a new way for 2D particle assembly based on the synchronize d evolution of centrosymmetric OA-AVs using a simplified single-sided source array,exhibiting excellent potential for the precise navigation and manipulation of cells and particles in biomedical applications.
基金This work was supported by the National Natural Science Foundation of China(Nos.21925505,52003195,and 22101207)Shanghai International Scientific Collaboration Fund(No.21520710100)+1 种基金the China Postdoctoral Science Foundation(Nos.2019M661614 and 2020M671197)J.D.is a recipient of the National Science Fund for Distinguished Young Scholars.
文摘What is the most favorite and original chemistry developed in your research group?Ring-opening polymerization-induced self-assembly of N-carboxyanhydrides(NCA-PISA),and fusion-induced particle assembly(FIPA).How do you get into this specific field?Could you please share some experiences with our readers?NCA-PISA was developed to solve the biodegradability problem of nanoparticles by traditional PISA,while FIPA was inspired by nature.
基金supported by the National Natural Science Foundation of China(11072046,10672033,90715011 and 11102036)the National Basic Research and Development Program(973Program,2010CB731502)
文摘The fine-scale heterogeneity of granular material is characterized by its polydisperse microstructure with randomness and no periodicity. To predict the mechanical response of the material as the microstructure evolves, it is demonstrated to develop computational multiscale methods using discrete particle assembly-Cosserat continuum modeling in micro- and macro- scales,respectively. The computational homogenization method and the bridge scale method along the concurrent scale linking approach are briefly introduced. Based on the weak form of the Hu-Washizu variational principle, the mixed finite element procedure of gradient Cosserat continuum in the frame of the second-order homogenization scheme is developed. The meso-mechanically informed anisotropic damage of effective Cosserat continuum is characterized and identified and the microscopic mechanisms of macroscopic damage phenomenon are revealed. c 2013 The Chinese Society of Theoretical and Applied Mechanics. [doi: 10.1063/2.1301101]
基金supported by the National Natural Science Foundation of China(Grant No.20273050)the National High Technology Research and Development Program of China(Grant Nos.2003AA2Z2031 and 2005AA205220)
文摘Micrometer-sized Fe3O4 particles and nano-sized gold particles were first synthesized by methods of self-aggregation of surface-chemically modified Fe3O4 nanoparticles and citrate reduction of the Au3+to Au0,respectively.Interaction between these two types of particles resulted in the assembly of nano-sized gold particles on the surface of the micrometer-sized Fe3O4 particles,forming an assembled structure with the Fe3O4 core particles around which are attached nano-sized gold parti-cles.The Fe3O4/Au structure is named GoldMag particles with assembled structure.The synthetic process,structure,and magnetic property of the GoldMag particles were analyzed.GoldMag particles with assembled structure have an irregular shape,rough surface with a diameter of 2―3μm.These particles exhibit the superparamagnetic property with saturated magnetization of 41 A·m2/kg.In a single step,antibodies could be readily immobilized onto the surface of the particles with a high binding capacity.The GoldMag particles can be used as a novel carrier in immunoassays.The maximum quantity of human IgG immobilized onto GoldMag particles was 330μg/mg.In order to validate the quality of the GoldMag particles as immunoassay carriers,an immunoassay system was used.The relative amount of immobilized human IgG was measured by HRP-labeled anti human IgG.The coefficient of variation within parallel samples of each group was below 6%and the coefficient of variation of means between five groups carried out separately was below 7%.Based on the sandwich method,the Hepatitis B surface antigen(HBsAg)and interleukin-8(IL-8)were also analyzed by qualitative and quantitative detection,respectively.The result indicated that the GoldMag particles with assembled structure were an ideal carrier in immunoassay.