Machining steel ball is complex procedure between abrasion trays and steel ball group, its basic condition is equal probability of cutting and selectivity of R. The analyzing discussion in this paper has been made in ...Machining steel ball is complex procedure between abrasion trays and steel ball group, its basic condition is equal probability of cutting and selectivity of R. The analyzing discussion in this paper has been made in more detail for a lot of affecting factors, providing a new thinking model for study on shaping mechanism of steel ball and its affect factors.展开更多
To study the chemical constituents of Hedysarum gmelinii. Methods Theconstituents were separated and purified by different methods of chromatography, and theirstructures were elucidated by DR, MS and NMR. Results Eigh...To study the chemical constituents of Hedysarum gmelinii. Methods Theconstituents were separated and purified by different methods of chromatography, and theirstructures were elucidated by DR, MS and NMR. Results Eight compounds were isolated from Hedysarumgmelinii, including three triteipenoids, two flavonoids and two other compounds. Their structureswere identified as squasapogenol (1), soyasapogenol (2), lupeol (3), 3, 9-dihydroxy coumestan (4),3-hydroxy-9-me-thoxy pterocarpan (5), β-sitosterol (6), palmatic acid (7), and hexadecanoic acid 2,3-dihydroxypropyl ester (8). Conclusion All the compounds have been isolated from this plant forthe first time. Compounds 1 — 4 and 8 were obtained from this genus for the first time. The NMRdata of 1 are reported for the first time.展开更多
Based on the bulging principle of different ellipticity dies, the methyl vinyl silicone rubber with excellent thermal stability and heat transfer performance was chosen as the viscous medium. The finite element analys...Based on the bulging principle of different ellipticity dies, the methyl vinyl silicone rubber with excellent thermal stability and heat transfer performance was chosen as the viscous medium. The finite element analysis and experiments of viscous warm pressure bulging (VWPB) of AZ31B magnesium alloy were conducted to analyze the influence of different ellipticity dies on the formability of AZ31B magnesium alloy. At the same time, based on the grid strain rule, the forming limit diagram (FLD) of VWPB of AZ31B magnesium alloy was obtained through measuring the strain of bulging specimens. The results showed that at the temperature range of viscous medium thermal stability, the viscous medium can fit the geometry variation of sheet and generate non-uniform pressure field, and as the die ellipticity increases, the difference value of non-uniform pressure reduces. Meanwhile, according to the FLD, the relationship between part complexity and ultimate deformation was investigated.展开更多
文摘Machining steel ball is complex procedure between abrasion trays and steel ball group, its basic condition is equal probability of cutting and selectivity of R. The analyzing discussion in this paper has been made in more detail for a lot of affecting factors, providing a new thinking model for study on shaping mechanism of steel ball and its affect factors.
基金National Natural Science Foundation of China (20432030)
文摘To study the chemical constituents of Hedysarum gmelinii. Methods Theconstituents were separated and purified by different methods of chromatography, and theirstructures were elucidated by DR, MS and NMR. Results Eight compounds were isolated from Hedysarumgmelinii, including three triteipenoids, two flavonoids and two other compounds. Their structureswere identified as squasapogenol (1), soyasapogenol (2), lupeol (3), 3, 9-dihydroxy coumestan (4),3-hydroxy-9-me-thoxy pterocarpan (5), β-sitosterol (6), palmatic acid (7), and hexadecanoic acid 2,3-dihydroxypropyl ester (8). Conclusion All the compounds have been isolated from this plant forthe first time. Compounds 1 — 4 and 8 were obtained from this genus for the first time. The NMRdata of 1 are reported for the first time.
基金Project(51575364)supported by the National Natural Science Foundation of ChinaProject(2013024014)supported by the Natural Foundation of Liaoning Province,China
文摘Based on the bulging principle of different ellipticity dies, the methyl vinyl silicone rubber with excellent thermal stability and heat transfer performance was chosen as the viscous medium. The finite element analysis and experiments of viscous warm pressure bulging (VWPB) of AZ31B magnesium alloy were conducted to analyze the influence of different ellipticity dies on the formability of AZ31B magnesium alloy. At the same time, based on the grid strain rule, the forming limit diagram (FLD) of VWPB of AZ31B magnesium alloy was obtained through measuring the strain of bulging specimens. The results showed that at the temperature range of viscous medium thermal stability, the viscous medium can fit the geometry variation of sheet and generate non-uniform pressure field, and as the die ellipticity increases, the difference value of non-uniform pressure reduces. Meanwhile, according to the FLD, the relationship between part complexity and ultimate deformation was investigated.