In pre-modern China,systematic records of astronomical phenomena measured by units including“zhang,”“chi,”and“cun”and records using phrases such as“as large as something”(making comparison with images取象比类)...In pre-modern China,systematic records of astronomical phenomena measured by units including“zhang,”“chi,”and“cun”and records using phrases such as“as large as something”(making comparison with images取象比类)were kept.Some of these records survive and together they constitute a“scale system”for records of astronomical phenomena.A textual model of the celestial sphere based on naked eye observations also survives.According to this model and using the conversion ratio that 1 chi equals 1 degree,the author has reconstituted the geometric meaning of the records of“zhang,”“chi,”and“cun,”while records that use a comparison with a certain object have been converted to their apparent diameters or magnitudes.Finally,these two records are integrated into one system.Through an analysis of the origin of the chi system,the author obtains the result that the radius of the celestial sphere when the ancients observed the sky with the naked eye was about 13 meters.The paper supports this conclusion from various perspectives,including psychological factors,the radius of planetariums,and the nautical Method of Reckoning by the Stars.As naked eye observers always regard the vault of heaven as a plane hemisphere,they have a common false impression in their minds;the pre-modern observational data therefore contains some systematic errors.Under different illumination and weather conditions,the vault of heaven is plane in varying degrees,for which the author has defined“the angle of apparent plane degree”视扁度角.To correct the visual errors,the author has devised a series of calculation tables for daytime,nighttime,cloudy days,clear days,moonlit nights,and moonless nights,to convert the apparent heights or sizes of celestial bodies to the true heights or sizes.展开更多
At present,the naked-eye three-dimensional(3D)display technology still has some drawbacks,such as low brightness uniformity,high crosstalk,low light efficiency,short viewing distance,and the manufacturing is difficult...At present,the naked-eye three-dimensional(3D)display technology still has some drawbacks,such as low brightness uniformity,high crosstalk,low light efficiency,short viewing distance,and the manufacturing is difficulty.Based on the principle of naked-eye 3D display and the Fresnel optical theory,this paper designs a Fresnel lens array and the star-shaped liquid crystal display(LCD)switch of unit LCD screen to achieve low-crosstalk and high brightness uniformity for the autostereoscopic 3D display.The unit parameters of a 139.7 cm 4K model autostereoscopic 3D displayer are provided and they are optimized by the TracePro software.The results show that when the pitch of the Fresnel lens on the exit surface is 0.304 mm,the width of each serration of Fresnel lens is 0.0234 mm,the length of the Fresnel lens is 2.87 mm,and the center height of star-shaped LCD switch is 0.030 mm,the center length is 0.040 mm,the width of star-shaped LCD switch is 0.050 mm,and the image crosstalk is less than 2%when the viewing distance is 2.50 m.The problem on the brightness of the image in different positions is improved.展开更多
Colorimetric sensing strategies as a powerful point-of-care testing(POCT) tool have attracted significant interest in various chem/biosensing applications.Taking the excellent bare-eye-detectable signaling feature,nan...Colorimetric sensing strategies as a powerful point-of-care testing(POCT) tool have attracted significant interest in various chem/biosensing applications.Taking the excellent bare-eye-detectable signaling feature,nanozymes-based colorimetric sensors enable more potential applications and have been a new forefront in the colorimetric POCT analysis toward different target analytes.However,the low catalytic activity of nanozymes in most cases limits their practical application.Recent efforts demonstrate that the aggregation-induced nanozymes provide a general means to modulate nanozymes activity and enhance colorimetric sensing performances of some nanozymes-based colorimetric sensors.But there are few reports are explored to discuss and review such aggregation-induced nanozymes and their colorimetric sensing applications.To highlight the advances and progress in aggregation-induced nanozymes based colorimetric assays,we herein summary the fundamentals,classify and applications of this newlydeveloping field,focusing on the aggregation-induced activity enhancement of nanozymes(AIAEnanozymes) with a significant "signal-on" feature and aggregation-induced activity inhibition of nanozymes(AIAI-nanozymes) with a dramatical "signal-of" characteristics.Finally,we also propose the current challenges and the future prospects on both AIAE-nanozymes and AIAI-nanozymes.展开更多
Objective: To study the effect of implantable posterior chamber phakic refractive lens (PC-PRL) in the treatment of high myopia and its effect on naked eye vision and retinal complications. Methods: A total of 110 pat...Objective: To study the effect of implantable posterior chamber phakic refractive lens (PC-PRL) in the treatment of high myopia and its effect on naked eye vision and retinal complications. Methods: A total of 110 patients (220 eyes) with high myopia admitted to our hospital from June 2017 to February 2019 were selected as subjects. All patients were treated with PC-PRL implantation. The UCVA, BCVA, intraocular pressure, corneal endothelial cell count and intraocular lens position (anterior chamber depth and arch height) were compared before and after the treatment. Results: 6 months after treatment, 68.18% of patients had UCVA between 0.6 and 0.9, 31.81% of patients had UCVA of more than 1.0, and 100.00% of patients had BCVA of more than1.0. The BCVA and UCVA values of patients at 1 week, 1 month, 3 months and 6 months after operation were significantly greater than those before surgery (P<0.05). There were no significant differences in BCVA and UCVA among 1 week, 1 month, 3 months and 6 months after operation (P>0.05). The intraocular pressure was significantly greater than that of the preoperative one week after operation (P<0.05). There was no significant difference between the intraocular pressure at 1 month, 3 months and 6 months after operation (P>0.05). There was no significant difference in corneal endothelial cell count and arch height before and after treatment (P>0.05). The depth of anterior chamber at 3 months and 6 months after operation was significantly less than that before operation (P<0.05). There was no significant difference in the anterior chamber depth between 3 months and 6 months after operation (P<0.05). There were 7 cases of corneal edema, 4 cases of high pressure eyes, 2 cases of refractive regression within 6 months, and 1 case of near-difficulty within 1 month. The total complication rate was 12.73%. Conclusion: PC-PRL implantation is effective in the treatment of high myopia, which can improve the naked eye and correct vision. At the same time, the incidence of retinal complications is low, which can be promoted and applied clinically.展开更多
A non-sulfur chemosensor based on an easy to prepare double naphthalene Schiff base is reported for the colorimetric and fluorometric dual-channel sensing of Hg2+ ions by taking advantage of the twisted intramolecular...A non-sulfur chemosensor based on an easy to prepare double naphthalene Schiff base is reported for the colorimetric and fluorometric dual-channel sensing of Hg2+ ions by taking advantage of the twisted intramolecular charge transfer (TICT) mechanism. This work provides a novel approach for the selective recognition of mercury ions. Moreover, this sensor serves as a potential recyclable component in sensing materials and the complex L-Hg2+ (L = 1-[(2-naphthalenylimino)methyl]-2-naphthalenol) can therefore be used as a fluorescent sensor for iodine anions. Notably, the color changes are very significant and all the recognition and recycling processes can be observed by the naked eye.展开更多
We have developed a microfluidic chip for colorimetric CH2+ detection. In this chip, it is facile to do colorimet- ric Cu2+ detection based on gold nanoparticles. This method has a dynamic detection range from 0.75 ...We have developed a microfluidic chip for colorimetric CH2+ detection. In this chip, it is facile to do colorimet- ric Cu2+ detection based on gold nanoparticles. This method has a dynamic detection range from 0.75 to 50 lamol/L with only 20μL solution including detection reagents and sample. The result can be readout by naked eye and pho-tographed by digital cameras. With the help of image processing software, we could measure the RGB value and calculate the Blue/Red ratio for more accurate quantification. Tap water could be detected in this portable chip.展开更多
文摘In pre-modern China,systematic records of astronomical phenomena measured by units including“zhang,”“chi,”and“cun”and records using phrases such as“as large as something”(making comparison with images取象比类)were kept.Some of these records survive and together they constitute a“scale system”for records of astronomical phenomena.A textual model of the celestial sphere based on naked eye observations also survives.According to this model and using the conversion ratio that 1 chi equals 1 degree,the author has reconstituted the geometric meaning of the records of“zhang,”“chi,”and“cun,”while records that use a comparison with a certain object have been converted to their apparent diameters or magnitudes.Finally,these two records are integrated into one system.Through an analysis of the origin of the chi system,the author obtains the result that the radius of the celestial sphere when the ancients observed the sky with the naked eye was about 13 meters.The paper supports this conclusion from various perspectives,including psychological factors,the radius of planetariums,and the nautical Method of Reckoning by the Stars.As naked eye observers always regard the vault of heaven as a plane hemisphere,they have a common false impression in their minds;the pre-modern observational data therefore contains some systematic errors.Under different illumination and weather conditions,the vault of heaven is plane in varying degrees,for which the author has defined“the angle of apparent plane degree”视扁度角.To correct the visual errors,the author has devised a series of calculation tables for daytime,nighttime,cloudy days,clear days,moonlit nights,and moonless nights,to convert the apparent heights or sizes of celestial bodies to the true heights or sizes.
基金supported by the 2022 Fujian Provincial Young and Middle-aged Teacher Education and Research Project(Science and Technology)(No.JAT220468)the Xiamen Natural Science Foundation(No.3502Z20227334).
文摘At present,the naked-eye three-dimensional(3D)display technology still has some drawbacks,such as low brightness uniformity,high crosstalk,low light efficiency,short viewing distance,and the manufacturing is difficulty.Based on the principle of naked-eye 3D display and the Fresnel optical theory,this paper designs a Fresnel lens array and the star-shaped liquid crystal display(LCD)switch of unit LCD screen to achieve low-crosstalk and high brightness uniformity for the autostereoscopic 3D display.The unit parameters of a 139.7 cm 4K model autostereoscopic 3D displayer are provided and they are optimized by the TracePro software.The results show that when the pitch of the Fresnel lens on the exit surface is 0.304 mm,the width of each serration of Fresnel lens is 0.0234 mm,the length of the Fresnel lens is 2.87 mm,and the center height of star-shaped LCD switch is 0.030 mm,the center length is 0.040 mm,the width of star-shaped LCD switch is 0.050 mm,and the image crosstalk is less than 2%when the viewing distance is 2.50 m.The problem on the brightness of the image in different positions is improved.
基金the National Natural Science Foundation of China(Nos.21765013,21665023)Key Talent Project of Gansu Province,“Feitian Scholar”Program of Gansu Province,and the Research Projects of Universities in Gansu Province(No.2017A115)for financially supporting this research。
文摘Colorimetric sensing strategies as a powerful point-of-care testing(POCT) tool have attracted significant interest in various chem/biosensing applications.Taking the excellent bare-eye-detectable signaling feature,nanozymes-based colorimetric sensors enable more potential applications and have been a new forefront in the colorimetric POCT analysis toward different target analytes.However,the low catalytic activity of nanozymes in most cases limits their practical application.Recent efforts demonstrate that the aggregation-induced nanozymes provide a general means to modulate nanozymes activity and enhance colorimetric sensing performances of some nanozymes-based colorimetric sensors.But there are few reports are explored to discuss and review such aggregation-induced nanozymes and their colorimetric sensing applications.To highlight the advances and progress in aggregation-induced nanozymes based colorimetric assays,we herein summary the fundamentals,classify and applications of this newlydeveloping field,focusing on the aggregation-induced activity enhancement of nanozymes(AIAEnanozymes) with a significant "signal-on" feature and aggregation-induced activity inhibition of nanozymes(AIAI-nanozymes) with a dramatical "signal-of" characteristics.Finally,we also propose the current challenges and the future prospects on both AIAE-nanozymes and AIAI-nanozymes.
基金Sichuan provincial health and family planning commission universal application project(17PJ536)Mianyang science and technology bureau(15S-02-9)+1 种基金The health bureau of Mianyang city(2014010)Mianyang health bureau(201310)
文摘Objective: To study the effect of implantable posterior chamber phakic refractive lens (PC-PRL) in the treatment of high myopia and its effect on naked eye vision and retinal complications. Methods: A total of 110 patients (220 eyes) with high myopia admitted to our hospital from June 2017 to February 2019 were selected as subjects. All patients were treated with PC-PRL implantation. The UCVA, BCVA, intraocular pressure, corneal endothelial cell count and intraocular lens position (anterior chamber depth and arch height) were compared before and after the treatment. Results: 6 months after treatment, 68.18% of patients had UCVA between 0.6 and 0.9, 31.81% of patients had UCVA of more than 1.0, and 100.00% of patients had BCVA of more than1.0. The BCVA and UCVA values of patients at 1 week, 1 month, 3 months and 6 months after operation were significantly greater than those before surgery (P<0.05). There were no significant differences in BCVA and UCVA among 1 week, 1 month, 3 months and 6 months after operation (P>0.05). The intraocular pressure was significantly greater than that of the preoperative one week after operation (P<0.05). There was no significant difference between the intraocular pressure at 1 month, 3 months and 6 months after operation (P>0.05). There was no significant difference in corneal endothelial cell count and arch height before and after treatment (P>0.05). The depth of anterior chamber at 3 months and 6 months after operation was significantly less than that before operation (P<0.05). There was no significant difference in the anterior chamber depth between 3 months and 6 months after operation (P<0.05). There were 7 cases of corneal edema, 4 cases of high pressure eyes, 2 cases of refractive regression within 6 months, and 1 case of near-difficulty within 1 month. The total complication rate was 12.73%. Conclusion: PC-PRL implantation is effective in the treatment of high myopia, which can improve the naked eye and correct vision. At the same time, the incidence of retinal complications is low, which can be promoted and applied clinically.
基金supported by the National Natural Science Foundation of China (21064006, 21161018)the Natural Science Foundation of Gansu Province (1010RJZA018)the Program for Changjiang Scholars and Innovative Research Teams in Universities of the Ministry of Education of China (IRT1177)
文摘A non-sulfur chemosensor based on an easy to prepare double naphthalene Schiff base is reported for the colorimetric and fluorometric dual-channel sensing of Hg2+ ions by taking advantage of the twisted intramolecular charge transfer (TICT) mechanism. This work provides a novel approach for the selective recognition of mercury ions. Moreover, this sensor serves as a potential recyclable component in sensing materials and the complex L-Hg2+ (L = 1-[(2-naphthalenylimino)methyl]-2-naphthalenol) can therefore be used as a fluorescent sensor for iodine anions. Notably, the color changes are very significant and all the recognition and recycling processes can be observed by the naked eye.
文摘We have developed a microfluidic chip for colorimetric CH2+ detection. In this chip, it is facile to do colorimet- ric Cu2+ detection based on gold nanoparticles. This method has a dynamic detection range from 0.75 to 50 lamol/L with only 20μL solution including detection reagents and sample. The result can be readout by naked eye and pho-tographed by digital cameras. With the help of image processing software, we could measure the RGB value and calculate the Blue/Red ratio for more accurate quantification. Tap water could be detected in this portable chip.