A novel pneumatic recovery method was proposed to curb the problem of high losses caused by side-cutting in a rapeseed combine harvester header.The influence of recovery method and material status changes on the recov...A novel pneumatic recovery method was proposed to curb the problem of high losses caused by side-cutting in a rapeseed combine harvester header.The influence of recovery method and material status changes on the recovery effect was studied via the CFD-DEM(computational fluid dynamic-discrete element method)coupling simulation.The effect of airflow action on the recovery effect was compared and analyzed,and the composite pneumatic recovery method was determined.In addition,the influence of material status changes and material feeding rate on the recovery effect was explored,and the critical condition of material blockage in the recovery device was configured.As such,the relationship model between air velocity and recovery rate was constructed and the air distribution ratio of the flow field in the device under this condition was optimized,had verified the rationality of this pneumatic recovery method was verified by a series of field tests.The average rapeseed recovery rate of 92.95%was achieved with the application of the recovery device,and the total loss rate of the header reduced by 52.26%,which is of great significance in reducing the total loss rate of the combine harvesters and improving the operation performance of machinery.The research results can provide a reference for the design of the header structure of a rape combine harvester.展开更多
AIM: To investigate and evaluate healing patterns around flaps made with different side-cut angulations after femtosecond laser in situ keratomileusis(FS-LASIK).METHODS: Thirty-four patients(68 eyes) received a 90...AIM: To investigate and evaluate healing patterns around flaps made with different side-cut angulations after femtosecond laser in situ keratomileusis(FS-LASIK).METHODS: Thirty-four patients(68 eyes) received a 90° side-cut(n=34) or a 120° side-cut flaps(n=34) made with a femtosecond laser. One day, 1 wk, 1 and 3 mo postoperatively, side-cut scar was evaluated under slit-lamp photography according to a new grading system(Grade 0=transparent scar, 1=faint healing opacity, and 2=evident healing opacity). In vivo corneal confocal microscopy and anterior segment optical coherence tomography(AS-OCT) were used to observe wound-healing patterns around flap margin in the two groups. Sirius Scheimpflug Analyzer was also used to analyze higher order aberrations 3 mo after surgery.RESULTS: There were no significant differences in flap wound-healing patterns at each follow up between the two groups(P>0.05). Three months after surgery, the flap edge scar classified as Grade 0 had excellent apposition and rapid nerve regeneration. At 3 mm and 5 mm pupil diameters, there were significant differences in trefoil aberrations between the two groups(P<0.05), but no statistically significant differences were found in total higher order aberrations(HOAs), spherical aberrations or coma in any of the pupil size conditions(P>0.05).CONCLUSION: Flap edge scars classified as Grade 0 have excellent apposition and rapid nerve regeneration, and 120° side-cut angle flaps induce less trefoil aberrations after FS-LASIK.展开更多
基金This work was supported by the Key Research Program&Technology Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-ZDRW202105)China Agriculture Research System of MOF and MARA(CARS-12)+1 种基金Synergistic Innovation Center of Jiangsu Modern Agricultural Equipment and Technology(4091600002)Central Public-interest Scientific Institution Basal Research Fund for Chinese Academy of Tropical Agricultural Sciences(S202102-02).
文摘A novel pneumatic recovery method was proposed to curb the problem of high losses caused by side-cutting in a rapeseed combine harvester header.The influence of recovery method and material status changes on the recovery effect was studied via the CFD-DEM(computational fluid dynamic-discrete element method)coupling simulation.The effect of airflow action on the recovery effect was compared and analyzed,and the composite pneumatic recovery method was determined.In addition,the influence of material status changes and material feeding rate on the recovery effect was explored,and the critical condition of material blockage in the recovery device was configured.As such,the relationship model between air velocity and recovery rate was constructed and the air distribution ratio of the flow field in the device under this condition was optimized,had verified the rationality of this pneumatic recovery method was verified by a series of field tests.The average rapeseed recovery rate of 92.95%was achieved with the application of the recovery device,and the total loss rate of the header reduced by 52.26%,which is of great significance in reducing the total loss rate of the combine harvesters and improving the operation performance of machinery.The research results can provide a reference for the design of the header structure of a rape combine harvester.
基金Supported by the Science and Technology Program of Xi’an,China No.201805097YX5SF31(2)the Foundation of Shaanxi Province Key Research and Development Project (No.2018SF-216)。
文摘AIM: To investigate and evaluate healing patterns around flaps made with different side-cut angulations after femtosecond laser in situ keratomileusis(FS-LASIK).METHODS: Thirty-four patients(68 eyes) received a 90° side-cut(n=34) or a 120° side-cut flaps(n=34) made with a femtosecond laser. One day, 1 wk, 1 and 3 mo postoperatively, side-cut scar was evaluated under slit-lamp photography according to a new grading system(Grade 0=transparent scar, 1=faint healing opacity, and 2=evident healing opacity). In vivo corneal confocal microscopy and anterior segment optical coherence tomography(AS-OCT) were used to observe wound-healing patterns around flap margin in the two groups. Sirius Scheimpflug Analyzer was also used to analyze higher order aberrations 3 mo after surgery.RESULTS: There were no significant differences in flap wound-healing patterns at each follow up between the two groups(P>0.05). Three months after surgery, the flap edge scar classified as Grade 0 had excellent apposition and rapid nerve regeneration. At 3 mm and 5 mm pupil diameters, there were significant differences in trefoil aberrations between the two groups(P<0.05), but no statistically significant differences were found in total higher order aberrations(HOAs), spherical aberrations or coma in any of the pupil size conditions(P>0.05).CONCLUSION: Flap edge scars classified as Grade 0 have excellent apposition and rapid nerve regeneration, and 120° side-cut angle flaps induce less trefoil aberrations after FS-LASIK.
