OPTICAL MATERIALS
·
2024
·
IF 3.8
Shanshan Zhao,Saima Kanwal,Weiwen Su,Hui Lin,Zhaoxia Han,Songlin Zhuang,Dechao Yu,Dawei Zhang
On basis of fluorescence intensity ratio (FIR) over certain narrow coupled levels of rare-earth ions, up-conversion of RE-doped materials perform excellent temperature-sensing abilities for thermometry applications. A series of Pr 3+ /Gd 3+ co-doped Ca 2 Al 2 SiO 7 phosphors (Ca 2 Al 2 SiO 7 :Pr 3+ /Gd 3+ ) were prepared by a conventional high-temperature solid-state reaction. Under excitation of blue ∼445 nm, the Ca 2 Al 2 SiO 7 :Pr 3+ /Gd 3+ phosphor yields intense photoluminescence (PL) bands around 489, 528, 537, 580, 604, 613, and 646 nm due to electronic transition of 3 P 0 → 3 H 4 , 3 P 0 → 3 H 5 , 3 P 1 → 3 H 5 , 3 P 1 → 3 H 6 , 1 D 2 → 3 H 4 , 3 P 0 → 3 H 6 , and 3 P 0 → 3 F 2 of Pr 3+ , respectively. Their relative intensities are sensitively determined by Pr 3+ contents, which, from 0.1 % to 5 %, tune the emission color from pink to warm white under excitation of 445 nm. It is of great interest that intense irradiation using a blue ∼445 laser does make efficient ultraviolet B (UVB) up-conversion at about 297, 306, and 313 nm, just stemming from the 6 P 3/2 → 8 S 7/2 , 6 P 5/2 → 8 S 7/2 , and 6 P 7/2 → 8 S 7/2 of Gd 3+ , respectively. A typical two-photon absorption process was proved to account for the UVB up-conversion, i.e. successive absorption of two blue ∼445 nm photons populating Pr 3+ 4f5d excited state, which further efficiently transfer its energy to the 6 I J / 6 P J states of Gd 3+ neighbor for UVB emission. Moreover, the thermally coupled levels (TCLs) of Gd 3+ : 6 P 3/2 - 6 P 7/2 , and Gd 3+ : 6 P 5/2 - 6 P 7/2 were thoroughly investigated for temperature sensing in 298–598 K. Maximum relative sensitivity of the 6 P 3/2 - 6 P 7/2 TCLs, i.e. S r (I 306 /I 313 ), is proved to be 0.96 % K −1 at 298 K, and that of the 6 P 5/2 - 6 P 7/2 TCLs, i.e. S r (I 297 /I 313 ), is 1 % K −1 at 373 K. The relevant thermal stabilities of the Ca 2 Al 2 SiO 7 :Pr 3+ /Gd 3+ thermometric candidate was well validated with 10 cycles of heating and cooling processes in 298–598 K. Such continuous explorations of Pr 3+ /Gd 3+ co-doping system will significantly promote the development of robust UVB up-converting phosphors as well as their practical applications in the field of high-resolution optical thermometry.
研究领域:
材料科学
·
光学
·
热测量技术
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Xiaohui Wang,Jingjie Cao,Xin Cheng,Xuyang Liu,Wenfeng Zhu,Yan Li,Xiaochun Wan,Shengkeng Chen,Linlin Liu
Solar withering is essential for the aroma formation of oolong tea, but due to the rainy and humid weather in plantation areas, solar withering became insufficient which seriously limits high-grade oolong tea production. This study aims to investigate ultraviolet B (UV-B) effects on the aroma characteristics of oolong tea and its feasibility in improving tea aroma quality. Sensory evaluation, odorant quantitation, and aroma characteristic analysis suggested UV-B application during the aeration process provided similar effects as solar withering in improving the aroma quality of oolong tea. UV-B application significantly increased fruity and floral odorants (4-hexanolide, α -farnesene, and β -ocimene by 44%, 74%, and 37%, respectively), and decreased green and fatty odorants (hexanal, ( E )-2-octenal, and ( Z )-4-heptenal by 42%, 45%, and 27%, respectively). These indicate UV-B is crucial for the flowery and fruity aroma formation of oolong tea, which can be potentially applied to oolong tea production, especially under unsunny weather.
研究领域:
食品科学
·
植物生理学
✓ 已验证
DOI
PubMed
高影响因子
PLANT PHYSIOLOGY AND BIOCHEMISTRY
·
2025
·
IF 5.7
Jiafei Qian,Chuanhong Ren,Fan Wang,Yunlin Cao,Yan Guo,Xiaoyong Zhao,Yilong Liu,Changqing Zhu,Xiaoying Li,Hongxia Xu,Junwei Chen,Kunsong Chen,Xian Li
Flavonol glycosides are secondary metabolites important for plant development and stress defense such as UV-B irradiation. UDP-glycosyltransferase (UGT) is the last enzyme step that catalyzes flavonol glycosides biosynthesis. Eriobotrya japonica is abundant in flavonol glycosides, but UGTs responsible for accumulation of flavonol glycosides remain unknown. Here, 13 flavonol glycosides including monoglycosides and diglycosides were characterized in different tissues of loquat by LC-MS/MS. UV-B irradiation significantly increased the accumulation of four quercetin glycosides and two kaempferol glycosides in loquat fruit. Based on UGT gene family analysis, transcriptome analysis, enzyme assays of recombinant proteins as well as transient overexpression assays in Nicotiana benthamiana , three UGTs were identified, i.e. EjUGT78T4 as flavonol 3- O -galactosyltransferase, EjUGT78S3 as flavonol 3- O -glucosyltransferase, and EjUGT91AK7 as flavonol 1→6 rhamnosyltransferase. This work elucidates the formation of flavonol glycosides in loquat through UGT-mediated glycosylation.
研究领域:
植物学
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分子生物学
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代谢组学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 42
·15539-15548
·
IF 4
Shanshan Zhao,Benchun Li,Tiantian Shen,Fang Fang,Songlin Zhuang,Dawei Zhang,Dechao Yu
Development of novel ultraviolet (UV) upconversion materials has been emerging as a hot research topic for application in tunable UV lasers, photocatalysis, sterilization, tagging, and most recently luminescence thermometry. We readily synthesized a series of Ho3+/Gd3+ co-doped LiYO2 upconversion phosphors by a traditional high-temperature reaction. Under excitation from a blue ∼445 nm laser, LiYO2:Ho3+,Gd3+ polycrystalline powders yield intense sharp ultraviolet B (UVB) upconversion luminescence from Gd3+ 6Pj (j = 7/2, 5/2, 3/2) excited states. By means of steady and dynamic photoluminescence spectra, we systematically investigated the involved two-photon absorption upconversion as well as the accompanying energy transfer processes between Ho3+ and Gd3+ ions in the LiYO2 host lattice. Interestingly, the distinguishable UVB luminescence constituents from Gd3+ 6Pj excited states exhibit sensitive temperature dependence in a 353–673 K range. Shedding light on thermal equilibria between Gd3+ 6Pj UV-emitting levels, their luminescence intensity ratios follow Boltzmann statistics for the application of new luminescence thermometry. For the scheme of 6P7/2–6P3/2 thermally coupled levels, it works over a temperature range of 373–673 K with a maximum relative sensitivity (Sr) of about 1.07% K−1 at 373 K, and its 6P7/2–6P5/2 counterpart works over 353–533 K with a maximum Sr of about 0.83% K−1 at 353 K. Overall, our study provides a new pathway to develop UV upconversion materials, and promotes the application of Gd3+-related UV luminescence constituents in sensitive temperature sensing over a wide temperature range.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DALTON TRANSACTIONS
·
2021
·Vol. 50
·期 42
·15413-15421
·
IF 4.39
Jingwei Liu,Yanjie Liang,Shao Yan,Dongxun Chen,Shihai Miao,Weili Wang
Luminescent materials that emit in the narrowband ultraviolet-B (NB-UVB; 310–313 nm) spectral region have attracted considerable attention due to their unique spectral features, which endow them with great potential applications in the fields of photochemistry and photomedicine. However, NB-UVB persistent luminescent materials are relatively lacking, especially materials that are excitable by natural sunlight. Here we report the NB-UVB persistent luminescence of Gd3+ in (Y,Gd)3Ga5O12:Bi3+ garnets by making use of the persistent energy transfer from Bi3+ to Gd3+. The optimal Bi3+ and Gd3+ concentrations for the maximum energy transfer efficiency are determined and persistent NB-UVB light emission with a peak wavelength at 313 nm and an afterglow time of more than 24 h is successfully achieved in the (Y,Gd)3Ga5O12:Bi3+ phosphor. More importantly, the as-synthesized NB-UVB persistent phosphors are also excitable by the widely available natural sunlight and exhibit exceptional NB-UVB persistent luminescence performance. Benefitting from the visible-blind emission feature, interference-free capability from indoor ambient light and self-sustained optical characteristic, the developed sunlight-excitable NB-UVB persistent phosphors here not only hold great promise for covert optical tagging applications, but also open new opportunities for optical data storage in a bright indoor environment.
研究领域:
材料科学
·
光物理学
·
生物医学工程
·
光学成像
·
药物递送系统
✓ 已验证
DOI
高影响因子
Plants-Basel
·
2025
·Vol. 14
·期 1
·133
·
IF 4.1
Wang Yu,Xiangru Zhou,Jinhao Meng,Hongwei Xu,Xiaofu Zhou
The depletion of the ozone layer has resulted in elevated ultraviolet-B (UV-B) radiation levels, posing a significant risk to terrestrial plant growth.Rhododendron chrysanthumPall. (R. chrysanthum), adapted to high-altitude and high-irradiation environments, has developed unique adaptive mechanisms. This study exposedR. chrysanthumto UV-B radiation for two days, with an 8 h daily treatment, utilizing metabolomic and transcriptomic analyses to explore the role of WRKY transcription factors in the plant’s UV-B stress response and their regulation of flavonoid synthesis. UV-B stress resulted in a significant decrease in rETR and Ik and a significant increase in 1-qP. These chlorophyll fluorescence parameters indicate that UV-B stress impaired photosynthesis inR. chrysanthum. Faced with the detrimental impact of UV-B radiation,R. chrysanthumis capable of mitigating its effects by modulating its flavonoid biosynthetic pathways to adapt positively to the stress. This study revealed changes in the expression of 113 flavonoid-related metabolites and 42 associated genes, with WRKY transcription factors showing significant correlation with these alterations. WRKY transcription factors can influence the expression of key enzyme genes in the flavonoid metabolic pathway, thereby affecting metabolite production. A theoretical reference for investigating plant stress physiology is provided in this work, which also offers insights into the stress responses of alpine plants under adverse conditions.
研究领域:
植物学
·
分子生物学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）