Graphene oxide(GO)nanosheets and onion‐like carbon(OLC)nanoparticles were synthesized from natural graphite powder and candle soot,respectively,and characterized by transmission electron microscopy and Raman spectros...Graphene oxide(GO)nanosheets and onion‐like carbon(OLC)nanoparticles were synthesized from natural graphite powder and candle soot,respectively,and characterized by transmission electron microscopy and Raman spectroscopy.The lubricating performances of GO and OLC as lubricant additives in water were comparatively evaluated using a ball‐on‐disc tribometer.The effects of sand blasting of a steel disc on its morphology and tribological property were evaluated.The results show that the two nanomaterials,GO and OLC,when used as lubricant additives in water effectively reduce the friction and wear of the sliding discs,which is independent of the disc surface treatment.On applying heavy loads,it is observed that GO exhibits superior friction‐reducing and anti‐wear abilities compared to those of OLC—a trace amount of GO can achieve a lubricating ability equivalent to that of an abundant amount of OLC.Furthermore,it is observed that sand blasting cannot improve the wear resistance of the treated steel disc,even though the hardness of the disc increased after the treatment.The possible anti‐wear and friction‐reducing mechanisms of the GO and OLC as lubricant additives in water are discussed based on results for the wear surfaces obtained by scanning electron microscopy,Raman spectroscopy,and X‐ray photoelectron spectroscopy。展开更多
Background:Exercise is widely known to lower intraocular pressure and increase ocular blood flow,which may be beneficial for glaucoma management.However,there are few studies that have reported on the relationship bet...Background:Exercise is widely known to lower intraocular pressure and increase ocular blood flow,which may be beneficial for glaucoma management.However,there are few studies that have reported on the relationship between exercise and glaucoma progression.The aim of our study was to investigate the exercise habits of those with primary open angle glaucoma(POAG)and its association with the progression of visual field(VF)loss.Methods:Daily physical activity(PA)was monitored by an accelerometer(ActiGraph wGT3x-BT)which patients wore for more than 10 h of being awake on their right wrists for 1 week.Results:Seventy-one non-progressive and 27 progressive patients were enrolled in the study.24-h moderate to vigorous physical activity(MVPA)exercise showed that POAG patients had similar variation trends consisting of 3 wave peaks and 2 wave hollows.Minutes spent in MVPA was 19.89±15.81 and 21.62±15.10 during 07:00–09:00 h(p=0.204),15.40±14.49 and 15.67±12.43 during 15:00–17:00 h(p=0.822)and 17.26±21.11 and 11.42±11.58 during 18:00–20:00 h(p=0.001)in the non-progressive and progressive group,respectively.Univariate analysis indicated that 10 min of MVPA(18:00–20:00 h)[odds ratio,OR(95%CI)=0.82(0.73,0.92)],average mean arterial pressure[OR(95%CI)=0.96(0.94,0.98)],age[OR(95%CI)=1.06(1.03,1.08)],male[OR(95%CI)=0.67(0.48,0.96)],spherical equivalent[OR(95%CI)=1.14(1.07,1.22)]and IOP-lowering medications[OR(95%CI)=1.54(1.16,2.05)]were significantly correlated with having progressive VF damage.Multivariable analysis showed that 10 min of MVPA(18:00–20:00 h)[OR(95%CI)=0.85(0.75,0.97)]was associated with progressive VF loss even after adjusting for other risk factors.Conclusions:Evening exercise may lower the odds of VF progression,suggesting that exercise habits possibly play an important role in glaucoma progression.展开更多
The multi-peak spectrum of Ti: sapphire pulses observed experimentally under ultra-broad bandwidth conditions ( 【 15 fs pulse length) has been explained theoretically. It is shown that the self-phase-modulation effec...The multi-peak spectrum of Ti: sapphire pulses observed experimentally under ultra-broad bandwidth conditions ( 【 15 fs pulse length) has been explained theoretically. It is shown that the self-phase-modulation effect is equivalent to the process of degenerate four-wave frequency-mixing. Based on this theoretical underpinning, the presence or absence of a multipeak spectrum provides a practical measure of whether the intracavity group-velocity-dispersion is ideally compensated for or not.展开更多
基金financial support of the National Natural Science Foundation of China(No.21473061)the Guangdong Natural Science Funds for Distinguished Young Scholar(No.2015A030306026)the Science and Technology Planning Project of Guangzhou City(No.201707010055)
文摘Graphene oxide(GO)nanosheets and onion‐like carbon(OLC)nanoparticles were synthesized from natural graphite powder and candle soot,respectively,and characterized by transmission electron microscopy and Raman spectroscopy.The lubricating performances of GO and OLC as lubricant additives in water were comparatively evaluated using a ball‐on‐disc tribometer.The effects of sand blasting of a steel disc on its morphology and tribological property were evaluated.The results show that the two nanomaterials,GO and OLC,when used as lubricant additives in water effectively reduce the friction and wear of the sliding discs,which is independent of the disc surface treatment.On applying heavy loads,it is observed that GO exhibits superior friction‐reducing and anti‐wear abilities compared to those of OLC—a trace amount of GO can achieve a lubricating ability equivalent to that of an abundant amount of OLC.Furthermore,it is observed that sand blasting cannot improve the wear resistance of the treated steel disc,even though the hardness of the disc increased after the treatment.The possible anti‐wear and friction‐reducing mechanisms of the GO and OLC as lubricant additives in water are discussed based on results for the wear surfaces obtained by scanning electron microscopy,Raman spectroscopy,and X‐ray photoelectron spectroscopy。
基金This study was supported by Wenzhou Medical University Research Fund.No.QTJ13009Zhejiang Province Health Innovation Talents Project no.2016025+1 种基金Key Discipline of the Eye Hospital,School of Ophthalmology and Optometry,Wenzhou Medical University Fund no.ZDZK201808the Innovation Research Project of the Eye Hospital of Wenzhou Medical University no.YNCX201308.
文摘Background:Exercise is widely known to lower intraocular pressure and increase ocular blood flow,which may be beneficial for glaucoma management.However,there are few studies that have reported on the relationship between exercise and glaucoma progression.The aim of our study was to investigate the exercise habits of those with primary open angle glaucoma(POAG)and its association with the progression of visual field(VF)loss.Methods:Daily physical activity(PA)was monitored by an accelerometer(ActiGraph wGT3x-BT)which patients wore for more than 10 h of being awake on their right wrists for 1 week.Results:Seventy-one non-progressive and 27 progressive patients were enrolled in the study.24-h moderate to vigorous physical activity(MVPA)exercise showed that POAG patients had similar variation trends consisting of 3 wave peaks and 2 wave hollows.Minutes spent in MVPA was 19.89±15.81 and 21.62±15.10 during 07:00–09:00 h(p=0.204),15.40±14.49 and 15.67±12.43 during 15:00–17:00 h(p=0.822)and 17.26±21.11 and 11.42±11.58 during 18:00–20:00 h(p=0.001)in the non-progressive and progressive group,respectively.Univariate analysis indicated that 10 min of MVPA(18:00–20:00 h)[odds ratio,OR(95%CI)=0.82(0.73,0.92)],average mean arterial pressure[OR(95%CI)=0.96(0.94,0.98)],age[OR(95%CI)=1.06(1.03,1.08)],male[OR(95%CI)=0.67(0.48,0.96)],spherical equivalent[OR(95%CI)=1.14(1.07,1.22)]and IOP-lowering medications[OR(95%CI)=1.54(1.16,2.05)]were significantly correlated with having progressive VF damage.Multivariable analysis showed that 10 min of MVPA(18:00–20:00 h)[OR(95%CI)=0.85(0.75,0.97)]was associated with progressive VF loss even after adjusting for other risk factors.Conclusions:Evening exercise may lower the odds of VF progression,suggesting that exercise habits possibly play an important role in glaucoma progression.
文摘The multi-peak spectrum of Ti: sapphire pulses observed experimentally under ultra-broad bandwidth conditions ( 【 15 fs pulse length) has been explained theoretically. It is shown that the self-phase-modulation effect is equivalent to the process of degenerate four-wave frequency-mixing. Based on this theoretical underpinning, the presence or absence of a multipeak spectrum provides a practical measure of whether the intracavity group-velocity-dispersion is ideally compensated for or not.
