Main quadrupole magnets are critical for the Circular Electron and Positron Collider(CEPC)and are specifically designed as dual aperture quadrupole(DAQ)magnets.However,the field crosstalk between the two apertures pre...Main quadrupole magnets are critical for the Circular Electron and Positron Collider(CEPC)and are specifically designed as dual aperture quadrupole(DAQ)magnets.However,the field crosstalk between the two apertures presents challenges.As the CEPC will work at four beam energies of Z,W,Higgs and ttbar mode,the DAQ magnets will operate at four field gradients spanning from 3.18 to 12.63 T/m.The first short quadrupole magnet prototype with the bore diameter of 76 mm and magnetic length of 1.0 m revealed the problems of large magnetic field harmonics and a magnetic center shift within the beam energy range.Accordingly,a compensation method was proposed in this work to solve the field crosstalk effect.By adjusting the gap height at the middle of the two apertures,the field harmonics and magnetic center shift are significantly reduced.After optimization,the short prototype was modified using a new scheme.The field simulations are validated from the magnetic measurement results.Further,the multipole field meets the requirements of the four beam energies.The detailed magnetic field optimization,field harmonics adjustment,and measurement results are presented herein.展开更多
While typesetting the article,in the Figs.13 and 17 there were several errors introduced.The correct Figs.13 and 17 are copied below:The original article has been corrected.
We investigated the compensatory trends of mesiodistal angulation of first molars in malocclusion cases. We compared differences in the angulation of first molars in different developmental stages, malocclusion classi...We investigated the compensatory trends of mesiodistal angulation of first molars in malocclusion cases. We compared differences in the angulation of first molars in different developmental stages, malocclusion classifications and skeletal patterns. The medical records and lateral cephalogrammes of 1 403 malocclusion cases taken before treatment were measured to evaluate compensation of molar angulation in relation to the skeletal jaw. The cases were stratified by age, Angle classification and skeletal patterns. Differences in the mesiodistal angulation of the first molars were compared among the stratifications. We observed three main phenomena. First,angulation of the upper first molar varied significantly with age and tipped most distally in cases aged,12 years and least distally in cases aged.16 years. The lower first molar did not show such differences. Second, in Angle Class II or skeletal Class II cases, the upper first molar was the most distally tipped, the lower first molar was the most mesially tipped, and opposite angulation compensation was observed in Class III cases. Third, in high-angle cases, the upper and lower first molars were the most distally tipped, and opposite angulation compensation was observed in low-angle cases. These data suggest that the angulation of the molars compensated for various growth patterns and malocclusion types. Hence, awareness of molar angulation compensation would help to adjust occlusal relationships, control anchorage and increase the chances of long-term stability.展开更多
Magnesite-bonded wood wool panel(MWWP)is an inorganic-bonded panel product in which wood excelsior is bonded with magnesite.Lowering the hygroscopicity is one of the key measures to improve the quality of the panel.In...Magnesite-bonded wood wool panel(MWWP)is an inorganic-bonded panel product in which wood excelsior is bonded with magnesite.Lowering the hygroscopicity is one of the key measures to improve the quality of the panel.In this study,moisture absorption mechanism of MWWP and measures generally applied to lower its hygroscopicity were reviewed.Three methods were then experimented to improve the dimensional stability of the panel,including adjusting the molar ratio of raw materials,adding additives and optimizing the conditioning process.The results showed that satisfying dimensional stability could be achieved when the molar ratio of MgO to MgCl_(2) was 5:1,the No.2 composite additive(aluminum powder+NH_(4)H_(2)PO_(4)+ferric alum)was adopted and a constant temperature and humidity treatment was applied in the first stage of conditioning.展开更多
文摘Main quadrupole magnets are critical for the Circular Electron and Positron Collider(CEPC)and are specifically designed as dual aperture quadrupole(DAQ)magnets.However,the field crosstalk between the two apertures presents challenges.As the CEPC will work at four beam energies of Z,W,Higgs and ttbar mode,the DAQ magnets will operate at four field gradients spanning from 3.18 to 12.63 T/m.The first short quadrupole magnet prototype with the bore diameter of 76 mm and magnetic length of 1.0 m revealed the problems of large magnetic field harmonics and a magnetic center shift within the beam energy range.Accordingly,a compensation method was proposed in this work to solve the field crosstalk effect.By adjusting the gap height at the middle of the two apertures,the field harmonics and magnetic center shift are significantly reduced.After optimization,the short prototype was modified using a new scheme.The field simulations are validated from the magnetic measurement results.Further,the multipole field meets the requirements of the four beam energies.The detailed magnetic field optimization,field harmonics adjustment,and measurement results are presented herein.
文摘While typesetting the article,in the Figs.13 and 17 there were several errors introduced.The correct Figs.13 and 17 are copied below:The original article has been corrected.
基金supported by the Specific Research Project of Health Pro Bono Sector, Ministry of Health, China (200802056)
文摘We investigated the compensatory trends of mesiodistal angulation of first molars in malocclusion cases. We compared differences in the angulation of first molars in different developmental stages, malocclusion classifications and skeletal patterns. The medical records and lateral cephalogrammes of 1 403 malocclusion cases taken before treatment were measured to evaluate compensation of molar angulation in relation to the skeletal jaw. The cases were stratified by age, Angle classification and skeletal patterns. Differences in the mesiodistal angulation of the first molars were compared among the stratifications. We observed three main phenomena. First,angulation of the upper first molar varied significantly with age and tipped most distally in cases aged,12 years and least distally in cases aged.16 years. The lower first molar did not show such differences. Second, in Angle Class II or skeletal Class II cases, the upper first molar was the most distally tipped, the lower first molar was the most mesially tipped, and opposite angulation compensation was observed in Class III cases. Third, in high-angle cases, the upper and lower first molars were the most distally tipped, and opposite angulation compensation was observed in low-angle cases. These data suggest that the angulation of the molars compensated for various growth patterns and malocclusion types. Hence, awareness of molar angulation compensation would help to adjust occlusal relationships, control anchorage and increase the chances of long-term stability.
基金This study is funded by National Natural Science Foundation(31070502)Public Farewell Project of National Forestry Bureau(201004006-6)support of the Priority Academic Program Development of Jiangsu Higher Education Institutions and Co-innovation Center of Efficient Processing and Utilization of Forest Resources,Nanjing Forestry University,Nanjing 210037,China.
文摘Magnesite-bonded wood wool panel(MWWP)is an inorganic-bonded panel product in which wood excelsior is bonded with magnesite.Lowering the hygroscopicity is one of the key measures to improve the quality of the panel.In this study,moisture absorption mechanism of MWWP and measures generally applied to lower its hygroscopicity were reviewed.Three methods were then experimented to improve the dimensional stability of the panel,including adjusting the molar ratio of raw materials,adding additives and optimizing the conditioning process.The results showed that satisfying dimensional stability could be achieved when the molar ratio of MgO to MgCl_(2) was 5:1,the No.2 composite additive(aluminum powder+NH_(4)H_(2)PO_(4)+ferric alum)was adopted and a constant temperature and humidity treatment was applied in the first stage of conditioning.
