The newly formulated non-Newtonian rivulet flows streaming down an inclined planar surface,with additional periodic perturbations arising from the application of the 2nd Stokes problem to the investigation of rivulet ...The newly formulated non-Newtonian rivulet flows streaming down an inclined planar surface,with additional periodic perturbations arising from the application of the 2nd Stokes problem to the investigation of rivulet dynamics,are demonstrated in the current research.Hereby,the 2nd Stokes problem assumes that the surface,with a thin shared layer of the fluid on it,oscillates in a harmonic manner along the x-axis of the rivulet flow,which coincides with the main flow direction streaming down the underlying surface.We obtain the exact extension of the rivulet flow family,clarifying the structure of the pressure field,which fully absorbs the arising perturbation.The profile of the velocity field is assumed to be Gaussian-type with a non-zero level of plasticity.Hence,the absolutely non-Newtonian case of the viscoplastic flow solution,which satisfies the motion and continuity equations,is considered(with particular cases of exact solutions for pressure).The perturbed governing equations of motion for rivulet flows then result in the Riccati-type ordinary differential equation(ODE),describing the dynamics of the coordinate x(t).The approximated schematic dynamics are presented in graphical plots.展开更多
AIM:To propose a novel classification system for late postoperative capsular block syndrome(CBS)based on the turbidity of intracapsular fluid,and to investigate the imaging and refractive changes before and after Nd:Y...AIM:To propose a novel classification system for late postoperative capsular block syndrome(CBS)based on the turbidity of intracapsular fluid,and to investigate the imaging and refractive changes before and after Nd:YAG laser posterior capsulotomy for each subtype.METHODS:A retrospective analysis was performed on 5 eyes from 5 patients with late postoperative CBS.Patients were categorized into turbid(3 eyes)or clear(2 eyes)types based on the turbidity of intracapsular fluid.Uncorrected visual acuity(UCVA),best-corrected visual acuity(BCVA),refractive status,slit-lamp images,Pentacam Scheimpflug data,and ultrasound biomicroscopy(UBM)images were evaluated before and 1mo after successful Nd:YAG laser posterior capsulotomy.RESULTS:Nd:YAG laser posterior capsulotomy significantly improved UCVA and BCVA in all 5 late CBS eyes.Pentacam imaging:turbid intracapsular fluid showed hyperreflection between posterior capsule and intraocular lens(IOL);clear fluid showed hyporeflection.UBM:posterior capsule was clear in turbid type but poorly defined in clear type.Capsulotomy increased aqueous depth only in clear type.Refractive changes:turbid fluid induced myopic shift.Clear type myopic shift was due to anterior IOL displacement and clear fluid-induced concave lens effect.CONCLUSION:Nd:YAG laser posterior capsulotomy is effective for late CBS.Turbid and clear late CBS types differ in imaging(Pentacam/UBM)and refractive mechanisms,supporting the proposed classification’s clinical value.展开更多
The combination of dual-main-phase(DMP)(Nd,Ce)-Fe-B magnets and grain boundary diffusion process(GBDP)is currently a research topic for obtaining high-cost performance materials in rare earth permanent magnet fields.T...The combination of dual-main-phase(DMP)(Nd,Ce)-Fe-B magnets and grain boundary diffusion process(GBDP)is currently a research topic for obtaining high-cost performance materials in rare earth permanent magnet fields.The novel structural features of GBDP(Nd,Ce)-Fe-B magnets give a version of different domain reversal processes from those of non-diffused magnets.In this work,the in-situ magnetic domain evolution of the DMP magnets was observed at elevated temperatures,and the temperature demagnetization and coercivity mechanism of the GBDP dual-main-phase(Nd,Ce)-Fe-B magnets are discussed.The results show that the shell composition of different types of grains in DMP magnets is similar,while the magnetic microstructure results indicate the Ce-rich grains tend to demagnetize first.Dy-rich shell with a high anisotropic field caused by GBDP leads to an increase in the nucleation field,which enhances the coercivity.It is found that much more grains exhibit single domain characteristics in the remanent state for GBDP dual-main-phase(Nd,Ce)-Fe-B magnets.In addition,the grains that undergo demagnetization first are Ce-rich or Nd-rich grains,which is different from that of non-diffused magnets.These results were not found in previous studies but can be intuitively characterized from the perspective of magnetic domains in this work,providing a new perspective and understanding of the performance improvement of magnetic materials.展开更多
文摘The newly formulated non-Newtonian rivulet flows streaming down an inclined planar surface,with additional periodic perturbations arising from the application of the 2nd Stokes problem to the investigation of rivulet dynamics,are demonstrated in the current research.Hereby,the 2nd Stokes problem assumes that the surface,with a thin shared layer of the fluid on it,oscillates in a harmonic manner along the x-axis of the rivulet flow,which coincides with the main flow direction streaming down the underlying surface.We obtain the exact extension of the rivulet flow family,clarifying the structure of the pressure field,which fully absorbs the arising perturbation.The profile of the velocity field is assumed to be Gaussian-type with a non-zero level of plasticity.Hence,the absolutely non-Newtonian case of the viscoplastic flow solution,which satisfies the motion and continuity equations,is considered(with particular cases of exact solutions for pressure).The perturbed governing equations of motion for rivulet flows then result in the Riccati-type ordinary differential equation(ODE),describing the dynamics of the coordinate x(t).The approximated schematic dynamics are presented in graphical plots.
基金Supported by the Research and Development Program of Shaanxi Province(No.2021SF-161)the Medical Research Project of Xi’an Science and Technology Action Plan[No.2019114613YX001SF041(1)]。
文摘AIM:To propose a novel classification system for late postoperative capsular block syndrome(CBS)based on the turbidity of intracapsular fluid,and to investigate the imaging and refractive changes before and after Nd:YAG laser posterior capsulotomy for each subtype.METHODS:A retrospective analysis was performed on 5 eyes from 5 patients with late postoperative CBS.Patients were categorized into turbid(3 eyes)or clear(2 eyes)types based on the turbidity of intracapsular fluid.Uncorrected visual acuity(UCVA),best-corrected visual acuity(BCVA),refractive status,slit-lamp images,Pentacam Scheimpflug data,and ultrasound biomicroscopy(UBM)images were evaluated before and 1mo after successful Nd:YAG laser posterior capsulotomy.RESULTS:Nd:YAG laser posterior capsulotomy significantly improved UCVA and BCVA in all 5 late CBS eyes.Pentacam imaging:turbid intracapsular fluid showed hyperreflection between posterior capsule and intraocular lens(IOL);clear fluid showed hyporeflection.UBM:posterior capsule was clear in turbid type but poorly defined in clear type.Capsulotomy increased aqueous depth only in clear type.Refractive changes:turbid fluid induced myopic shift.Clear type myopic shift was due to anterior IOL displacement and clear fluid-induced concave lens effect.CONCLUSION:Nd:YAG laser posterior capsulotomy is effective for late CBS.Turbid and clear late CBS types differ in imaging(Pentacam/UBM)and refractive mechanisms,supporting the proposed classification’s clinical value.
基金supported by the National Key Research and Development Program of China(Nos.2021YFB3503003,2021YFB3503100,and 2022YFB3505401).
文摘The combination of dual-main-phase(DMP)(Nd,Ce)-Fe-B magnets and grain boundary diffusion process(GBDP)is currently a research topic for obtaining high-cost performance materials in rare earth permanent magnet fields.The novel structural features of GBDP(Nd,Ce)-Fe-B magnets give a version of different domain reversal processes from those of non-diffused magnets.In this work,the in-situ magnetic domain evolution of the DMP magnets was observed at elevated temperatures,and the temperature demagnetization and coercivity mechanism of the GBDP dual-main-phase(Nd,Ce)-Fe-B magnets are discussed.The results show that the shell composition of different types of grains in DMP magnets is similar,while the magnetic microstructure results indicate the Ce-rich grains tend to demagnetize first.Dy-rich shell with a high anisotropic field caused by GBDP leads to an increase in the nucleation field,which enhances the coercivity.It is found that much more grains exhibit single domain characteristics in the remanent state for GBDP dual-main-phase(Nd,Ce)-Fe-B magnets.In addition,the grains that undergo demagnetization first are Ce-rich or Nd-rich grains,which is different from that of non-diffused magnets.These results were not found in previous studies but can be intuitively characterized from the perspective of magnetic domains in this work,providing a new perspective and understanding of the performance improvement of magnetic materials.
