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
A series of E and Z-isomers of 3-(4'-substituted benzylidene)-indolin-2-one derivatives were synthesized and separated. Based on their 1H NMR characterization, an unusual counterintuitive deshielding phenomenon for...A series of E and Z-isomers of 3-(4'-substituted benzylidene)-indolin-2-one derivatives were synthesized and separated. Based on their 1H NMR characterization, an unusual counterintuitive deshielding phenomenon for the protons presenting in the shielding zone of phenyl ring was observed and analyzed for the first time.展开更多
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%.
基金National Natural Science Foundation of China(Grant No.21172008 and 21372015)
文摘A series of E and Z-isomers of 3-(4'-substituted benzylidene)-indolin-2-one derivatives were synthesized and separated. Based on their 1H NMR characterization, an unusual counterintuitive deshielding phenomenon for the protons presenting in the shielding zone of phenyl ring was observed and analyzed for the first time.