We evaluated the effects of red and blue light on the repair of UV-B radiation-induced damage in tetraspores of Chondrus ocellatus Holm. Tetraspores of C. ocellatus were treated with different UV-B radiation levels(0,...We evaluated the effects of red and blue light on the repair of UV-B radiation-induced damage in tetraspores of Chondrus ocellatus Holm. Tetraspores of C. ocellatus were treated with different UV-B radiation levels(0,36,72,108,144 and 180 J/m2),and thereafter subjected to PAR,darkness,or red or blue light during a 2-h repair stage,each day for 48 days. The diameters and cellular contents of cyclobutane pyrimidine dimmers(CPDs),chlorophyll a(Chl a),phycoerythrin,and UV-B-absorbing mycosporinelike amino acids(MAAs) contents of the tetraspores were determined. Our results show that low doses of UV-B radiation(36 and 72 J/m 2) promoted the growth of C. ocellatus; however,increased UV-B radiation gradually reduced the C. ocellatus growth(greater than 72 J/m2). The MAAs(palythine and asterina-330) in C. ocellatus were detected and analyzed by LC/MS. Our results suggest that moderate red light could induce the growth of this alga in aquaculture. In addition,photorepair was inhibited by red light,so there may be some other DNA repair mechanism activated by red light. Blue light promoted the activity of DNA photolyase,greatly improving remediation efficiency. Red and blue lights were found to reduce the capacity of C. ocellatus to form MAAs. Therefore,PAR,red light,and blue light play different roles during the repair processes for damage induced by UV-B radiation.展开更多
A new Eu（III） complex, EuL3（phen）, was synthesized, where L is the abbreviation of de- protonated 1-（7-（tert-butyl）-9-ethyl-gH-carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione （HL）, phen is the abbreviation of...A new Eu（III） complex, EuL3（phen）, was synthesized, where L is the abbreviation of de- protonated 1-（7-（tert-butyl）-9-ethyl-gH-carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione （HL）, phen is the abbreviation of 1,10-phenanthroline. The Eu（III） complex was characterized by element analysis, IR, 1H NMR, UV-visible absorption spectroscopy, thermogravimetric anal- ysis （TGA）, and photoluminescence measurements （PL）. TGA shows that thermal stability of the complex is up to 325 ~C. PL measurement indicates that the Eu（III） complex exhibits intense red-emission and extends their excitation bands to visible region. LEDs device was successfully fabricated by precoating complex EuL3 （phen） onto 460 nm blue-emitting InGaN chip. The emission of device shows that the complex can act as red phosphor in combination with 460 nm blue-emitting chips. This europium complex based on 1-（7-（tert-butyl）-9- ethyl-9H-carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione is a kind of interesting red-emitting material excited by blue light, which could avoid the damage of excitation by UV light.展开更多
For healthy lighting,daily lighting that considers both visible light and near-infrared(NIR)light is necessary.However,at~900 nm,the extensively used solar-like phosphor-converted light-emitting diodes(pc-LEDs)are lim...For healthy lighting,daily lighting that considers both visible light and near-infrared(NIR)light is necessary.However,at~900 nm,the extensively used solar-like phosphor-converted light-emitting diodes(pc-LEDs)are limited by a lack of high-performance NIR luminescent materials.We report a broadband NIR phosphor Sr_(2)ScSbO_(6):Cr^(3+) with a double perovskite-type structure,thus simultaneously demonstrating high luminescence efficiency and good thermal stability.Under 550-nm excitation,Sr_(2)ScSbO_(6):Cr^(3+) demonstrates broadband NIR emission centered at~890 nm with luminescence internal/external efficiencies of 82.0%/35.7%,respectively.Furthermore,the luminescence integrated intensity at 430 K remains at~66.4% of the initial intensity.We successfully fabricated pc-LED devices using a 465-nm-sized blue chip and other commercial phosphors,presenting a relatively complete solar-like spectrum from blue to NIR light and is expected to be used in solar-like lighting.展开更多
基金Supported by the Program for New Century Excellent Talents in University(No.NCET-05-0597)the National Natural Science Foundation of China(No.30270258)
文摘We evaluated the effects of red and blue light on the repair of UV-B radiation-induced damage in tetraspores of Chondrus ocellatus Holm. Tetraspores of C. ocellatus were treated with different UV-B radiation levels(0,36,72,108,144 and 180 J/m2),and thereafter subjected to PAR,darkness,or red or blue light during a 2-h repair stage,each day for 48 days. The diameters and cellular contents of cyclobutane pyrimidine dimmers(CPDs),chlorophyll a(Chl a),phycoerythrin,and UV-B-absorbing mycosporinelike amino acids(MAAs) contents of the tetraspores were determined. Our results show that low doses of UV-B radiation(36 and 72 J/m 2) promoted the growth of C. ocellatus; however,increased UV-B radiation gradually reduced the C. ocellatus growth(greater than 72 J/m2). The MAAs(palythine and asterina-330) in C. ocellatus were detected and analyzed by LC/MS. Our results suggest that moderate red light could induce the growth of this alga in aquaculture. In addition,photorepair was inhibited by red light,so there may be some other DNA repair mechanism activated by red light. Blue light promoted the activity of DNA photolyase,greatly improving remediation efficiency. Red and blue lights were found to reduce the capacity of C. ocellatus to form MAAs. Therefore,PAR,red light,and blue light play different roles during the repair processes for damage induced by UV-B radiation.
文摘A new Eu（III） complex, EuL3（phen）, was synthesized, where L is the abbreviation of de- protonated 1-（7-（tert-butyl）-9-ethyl-gH-carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione （HL）, phen is the abbreviation of 1,10-phenanthroline. The Eu（III） complex was characterized by element analysis, IR, 1H NMR, UV-visible absorption spectroscopy, thermogravimetric anal- ysis （TGA）, and photoluminescence measurements （PL）. TGA shows that thermal stability of the complex is up to 325 ~C. PL measurement indicates that the Eu（III） complex exhibits intense red-emission and extends their excitation bands to visible region. LEDs device was successfully fabricated by precoating complex EuL3 （phen） onto 460 nm blue-emitting InGaN chip. The emission of device shows that the complex can act as red phosphor in combination with 460 nm blue-emitting chips. This europium complex based on 1-（7-（tert-butyl）-9- ethyl-9H-carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione is a kind of interesting red-emitting material excited by blue light, which could avoid the damage of excitation by UV light.
基金supported by the National Natural Science Foundation of China(51972020 and 51832005)。
文摘For healthy lighting,daily lighting that considers both visible light and near-infrared(NIR)light is necessary.However,at~900 nm,the extensively used solar-like phosphor-converted light-emitting diodes(pc-LEDs)are limited by a lack of high-performance NIR luminescent materials.We report a broadband NIR phosphor Sr_(2)ScSbO_(6):Cr^(3+) with a double perovskite-type structure,thus simultaneously demonstrating high luminescence efficiency and good thermal stability.Under 550-nm excitation,Sr_(2)ScSbO_(6):Cr^(3+) demonstrates broadband NIR emission centered at~890 nm with luminescence internal/external efficiencies of 82.0%/35.7%,respectively.Furthermore,the luminescence integrated intensity at 430 K remains at~66.4% of the initial intensity.We successfully fabricated pc-LED devices using a 465-nm-sized blue chip and other commercial phosphors,presenting a relatively complete solar-like spectrum from blue to NIR light and is expected to be used in solar-like lighting.
