Crust cooling of soft X-ray transients has been observed after outbursts,but an additional shallow heating during accretion in outburst is needed to explain the quiescent light curve.However,shallow heating is signifi...Crust cooling of soft X-ray transients has been observed after outbursts,but an additional shallow heating during accretion in outburst is needed to explain the quiescent light curve.However,shallow heating is significantly different between sources and even within one source between different outbursts,and the source of shallow heat is as yet unknown.Using the open source code"dStar"which solves the fully general relativistic heat diffusion equation for the crust,we investigate the effect of magnitude and depth of shallow heating on crust cooling and find that some exceptional sources(Swift J174805.3-244637,MAXI J0556-332 during outburstⅡand GRO J1750-27)in which shallow heating may be inactive could be explained by a deeper shallow heating mechanism.We compare our results with those from previous works and find that the shallow heating is model dependent.In addition,the effects of mass and radius of a neutron star on shallow heating are studied,and it is shown that the more compact the star,the less shallow heating will be needed to fit the crust cooling light curves.展开更多
Objective: Zirconia is increasingly being used in restorative dentistry but its removal is often a difficult procedure due to its resistance to cutting with conventional diamond burs. Zirconia cutting burs have been d...Objective: Zirconia is increasingly being used in restorative dentistry but its removal is often a difficult procedure due to its resistance to cutting with conventional diamond burs. Zirconia cutting burs have been developed and this study aims to compare 4 such burs. Methods: 35 experienced restorative dentists selected from our Practice Based Network (PBN) were asked to evaluate the cutting of a 1 mm groove into zirconia using 4 burs A (Meisinger), B (ZR2-1 experimental bur from DIATECH), C (Komet) & D (DIATECH Z-Rex, a bur designed with enhanced bonding of diamond grit to bur shank). Responses regarding cutting time, performance and wear were recorded. Results: For best cutting times and also overall performance D performed best and C the worst, with little difference between burs A and B. Bur C also performed least well for wear on the bur. Conclusion: The newly designed zirconia cutting bur DIATECH Z-Rex with enhanced bonding of diamond grit performed best in the analysis by the 35 dentists.展开更多
基金supported by the Natural Science Foundation of Xinjiang Province under Grant No.2020D01C063the National Natural Science Foundation of China(NSFC,Grant Nos.11763007,U2031204 and 11863005)。
文摘Crust cooling of soft X-ray transients has been observed after outbursts,but an additional shallow heating during accretion in outburst is needed to explain the quiescent light curve.However,shallow heating is significantly different between sources and even within one source between different outbursts,and the source of shallow heat is as yet unknown.Using the open source code"dStar"which solves the fully general relativistic heat diffusion equation for the crust,we investigate the effect of magnitude and depth of shallow heating on crust cooling and find that some exceptional sources(Swift J174805.3-244637,MAXI J0556-332 during outburstⅡand GRO J1750-27)in which shallow heating may be inactive could be explained by a deeper shallow heating mechanism.We compare our results with those from previous works and find that the shallow heating is model dependent.In addition,the effects of mass and radius of a neutron star on shallow heating are studied,and it is shown that the more compact the star,the less shallow heating will be needed to fit the crust cooling light curves.
文摘Objective: Zirconia is increasingly being used in restorative dentistry but its removal is often a difficult procedure due to its resistance to cutting with conventional diamond burs. Zirconia cutting burs have been developed and this study aims to compare 4 such burs. Methods: 35 experienced restorative dentists selected from our Practice Based Network (PBN) were asked to evaluate the cutting of a 1 mm groove into zirconia using 4 burs A (Meisinger), B (ZR2-1 experimental bur from DIATECH), C (Komet) & D (DIATECH Z-Rex, a bur designed with enhanced bonding of diamond grit to bur shank). Responses regarding cutting time, performance and wear were recorded. Results: For best cutting times and also overall performance D performed best and C the worst, with little difference between burs A and B. Bur C also performed least well for wear on the bur. Conclusion: The newly designed zirconia cutting bur DIATECH Z-Rex with enhanced bonding of diamond grit performed best in the analysis by the 35 dentists.
