The most important grinding processes were realized in a single pass of the grinding wheel,such as continuous path controlled grinding (CPCG/Peelgrinding/HSP),CPCG with reduced contact of the grinding wheel (Quickpoin...The most important grinding processes were realized in a single pass of the grinding wheel,such as continuous path controlled grinding (CPCG/Peelgrinding/HSP),CPCG with reduced contact of the grinding wheel (Quickpoint),single-pass longitudinal internal grinding,creep feed grinding (CFG),longitudinal cylindrical grinding with grinding wheels made of conventional abrasive materials and longitudinal internal cylindrical grinding using grinding wheels with zone-diversified structure.展开更多
Aim Paeoniflorin-6'O-benzene sulfonate (CP-25) was synthesized to improve oral absorption. This study was performed to investigate absorptive behavior and mechanism of CP-25 in intestine. Methods The effects of dru...Aim Paeoniflorin-6'O-benzene sulfonate (CP-25) was synthesized to improve oral absorption. This study was performed to investigate absorptive behavior and mechanism of CP-25 in intestine. Methods The effects of drug concentration, intestinal segments, gender as well as ATP binding cassette (ABC) transporter inhibitors on absorption of CP-25 were studied in a situ single-pass intestinal perfusion rat model. Meanwhile, Paeoniflorin (Pae) was tested and served as control group. The concentration of tested drugs was measured by HPLC. Results The results showed intestinal absorption of CP-25 was neither segmental dependent changes nor gender difference. Transepithelial transportation would not change with increasing concentrations of CP-25, which suggest a passive transport was the main pattern of CP-25. Additionally, absorption of CP-25 was much better than that of Pae in small intestine. When compared with Pae, CP-25 gave a 1.82-fold permeability rate. Finally, the results indicated Pae was substrate of P-glycoprotein (P-gp) , but was not the substrate of breast cancer resistance protein and muhi- drug resistance associated protein 2. Among the used ABC inhibitors, the absorption rate of Pae could only be in- creased by? P-gp inhibitor Verapamil and GF120918, while CP-25 had no remarkable alteration. Conclusion CP-25 has better absorptive features than that of Pae, which may be attributed to its lipophicity enhancement and be unaffected by P-gp efflux.展开更多
The selected modifications to the construction of grinding wheels were described which facilitate an increase in the material removal rate (grinding wheels with conic chamfer and grinding wheels with microdiscontinui...The selected modifications to the construction of grinding wheels were described which facilitate an increase in the material removal rate (grinding wheels with conic chamfer and grinding wheels with microdiscontinuities on the active surface). Using these background details, a suggested thesis was put forward regarding the need to develop a device which will allow for the shaping of the macrogeometry of the grinding wheel (cylindrical and conical surfaces) and the microdiscontinuities within the dressing operation simultaneously. The device was presented and prepared in two functional variants (horizontal and vertical mounting of the motor), then a prototype was described. An example of the grinding wheel active surface, shaped by using this device, was also presented. The theoretical analysis and experimental verification performed determine that the error of shaping the conic chamfer angle within the range of 0-1.5°, using the developed device, is approximately ±3%.展开更多
文摘The most important grinding processes were realized in a single pass of the grinding wheel,such as continuous path controlled grinding (CPCG/Peelgrinding/HSP),CPCG with reduced contact of the grinding wheel (Quickpoint),single-pass longitudinal internal grinding,creep feed grinding (CFG),longitudinal cylindrical grinding with grinding wheels made of conventional abrasive materials and longitudinal internal cylindrical grinding using grinding wheels with zone-diversified structure.
文摘Aim Paeoniflorin-6'O-benzene sulfonate (CP-25) was synthesized to improve oral absorption. This study was performed to investigate absorptive behavior and mechanism of CP-25 in intestine. Methods The effects of drug concentration, intestinal segments, gender as well as ATP binding cassette (ABC) transporter inhibitors on absorption of CP-25 were studied in a situ single-pass intestinal perfusion rat model. Meanwhile, Paeoniflorin (Pae) was tested and served as control group. The concentration of tested drugs was measured by HPLC. Results The results showed intestinal absorption of CP-25 was neither segmental dependent changes nor gender difference. Transepithelial transportation would not change with increasing concentrations of CP-25, which suggest a passive transport was the main pattern of CP-25. Additionally, absorption of CP-25 was much better than that of Pae in small intestine. When compared with Pae, CP-25 gave a 1.82-fold permeability rate. Finally, the results indicated Pae was substrate of P-glycoprotein (P-gp) , but was not the substrate of breast cancer resistance protein and muhi- drug resistance associated protein 2. Among the used ABC inhibitors, the absorption rate of Pae could only be in- creased by? P-gp inhibitor Verapamil and GF120918, while CP-25 had no remarkable alteration. Conclusion CP-25 has better absorptive features than that of Pae, which may be attributed to its lipophicity enhancement and be unaffected by P-gp efflux.
文摘The selected modifications to the construction of grinding wheels were described which facilitate an increase in the material removal rate (grinding wheels with conic chamfer and grinding wheels with microdiscontinuities on the active surface). Using these background details, a suggested thesis was put forward regarding the need to develop a device which will allow for the shaping of the macrogeometry of the grinding wheel (cylindrical and conical surfaces) and the microdiscontinuities within the dressing operation simultaneously. The device was presented and prepared in two functional variants (horizontal and vertical mounting of the motor), then a prototype was described. An example of the grinding wheel active surface, shaped by using this device, was also presented. The theoretical analysis and experimental verification performed determine that the error of shaping the conic chamfer angle within the range of 0-1.5°, using the developed device, is approximately ±3%.