White light illumination is essential in daily life,however,the substantial amount of blue light it contains can damage human eyes.Therefore,it is important to block this high-energy blue light to protect visual healt...White light illumination is essential in daily life,however,the substantial amount of blue light it contains can damage human eyes.Therefore,it is important to block this high-energy blue light to protect visual health.In this study,yellow-emitting carbon dots(CDs)with a quantum yield exceeding 94%were synthesized using citric acid and urea.These CDs effectively absorb blue light.By incorporating them into polystyrene,multiple films termed CDs-based blue light blocking films(CBFs)were developed,each offering different levels of blue light absorption.These CBFs exhibited excellent transparency and efficient blue light filtering capabilities.This study highlights the potential of high quantum yield CDs,which specifically absorb blue light,as foundational materials for developing light-blocking solutions against highenergy short-wavelength light.展开更多
Overexposure to ultraviolet(UV)and high-energy blue-violet light(HEBV)can cause severe skin and eye damage.In this study lignin-containing cellulose nanofibrils(LCNF)films are prepared from cellulose pulps with varyin...Overexposure to ultraviolet(UV)and high-energy blue-violet light(HEBV)can cause severe skin and eye damage.In this study lignin-containing cellulose nanofibrils(LCNF)films are prepared from cellulose pulps with varying lignin contents obtained through hydrogen peroxide-acetic acid pretreatment of bagasse.The LCNF films possess excellent hydrophobicity and mechanical properties,as well as certain UV radiation resistance properties,by leveraging the inherent properties of lignin.To enhance the UV shielding performance of LCNF films,blue-and green-emitting carbon dots(BL-CQDs,GL-CQDs)derived from lignin are prepared and incorporated as UV absorbers alongside LCNF to construct sustainable,biodegradable composite films with high-efficiency UV shielding properties,in which lignin-based carbon quantum dot(L-CQDs)are uniformly embedded within the LCNF network via hydrogen bonding.Through the synergistic interaction between lignin and L-CQDs,the UV blocking rate of L-CQDs@LCNF films increased by 8.15%-36.40%,and the HEBV blocking rate increased by 2.95%-41.52%while maintaining excellent visible light transmittance and mechanical properties(with tensile strength reaching up to 82 MPa),compared to pure LCNF films.Simultaneously,by regulating the lignin content in LCNF and the properties of L-CQDs,the films exhibit tunable UV blocking and blue-violet light shielding capabilities.Additionally,the prepared BL-CQDs achieve a fluorescence quantum yield of 31.10%,representing a leading level among lignin-derived CQDs.This study will provide a strategy for preparing transparent and full-lignocellulose films with tunable UV-blocking and blue-violet light shielding properties through a design integrating function and structure.展开更多
Visible light positioning （VLP） is an emerging candidate for indoor positioning, which carl simultaneously meet the requirements for accuracy, cost, coverage area, and security. However, intercell interference causc...Visible light positioning （VLP） is an emerging candidate for indoor positioning, which carl simultaneously meet the requirements for accuracy, cost, coverage area, and security. However, intercell interference causcd by light intensity superposition linfits the application of VLP. In this Letter, we propose a united block sequence mapping （UBSM）-based VLP that utilizes superposition to integrate the multidimensional information from dense small cells into 2D information. The experimental result shows that UBSM-based VLP can achieve an accuracy of 1.5 cm with a 0.4 m row spacing and 0.35 m column spacing of LED lights.展开更多
基金supported by Medical Science and Technology Research Project of Henan Province(Joint Construction Project)(No.LHGJ20200433)National Natural Science Foundation of China(No.52122308)。
文摘White light illumination is essential in daily life,however,the substantial amount of blue light it contains can damage human eyes.Therefore,it is important to block this high-energy blue light to protect visual health.In this study,yellow-emitting carbon dots(CDs)with a quantum yield exceeding 94%were synthesized using citric acid and urea.These CDs effectively absorb blue light.By incorporating them into polystyrene,multiple films termed CDs-based blue light blocking films(CBFs)were developed,each offering different levels of blue light absorption.These CBFs exhibited excellent transparency and efficient blue light filtering capabilities.This study highlights the potential of high quantum yield CDs,which specifically absorb blue light,as foundational materials for developing light-blocking solutions against highenergy short-wavelength light.
基金supported by the National Natural Science Foundation of China(Grant number 22268007)the Guangxi Natural Science Foun-dation of China(Grant numbers Guike AB25069140,GKAD25069076).
文摘Overexposure to ultraviolet(UV)and high-energy blue-violet light(HEBV)can cause severe skin and eye damage.In this study lignin-containing cellulose nanofibrils(LCNF)films are prepared from cellulose pulps with varying lignin contents obtained through hydrogen peroxide-acetic acid pretreatment of bagasse.The LCNF films possess excellent hydrophobicity and mechanical properties,as well as certain UV radiation resistance properties,by leveraging the inherent properties of lignin.To enhance the UV shielding performance of LCNF films,blue-and green-emitting carbon dots(BL-CQDs,GL-CQDs)derived from lignin are prepared and incorporated as UV absorbers alongside LCNF to construct sustainable,biodegradable composite films with high-efficiency UV shielding properties,in which lignin-based carbon quantum dot(L-CQDs)are uniformly embedded within the LCNF network via hydrogen bonding.Through the synergistic interaction between lignin and L-CQDs,the UV blocking rate of L-CQDs@LCNF films increased by 8.15%-36.40%,and the HEBV blocking rate increased by 2.95%-41.52%while maintaining excellent visible light transmittance and mechanical properties(with tensile strength reaching up to 82 MPa),compared to pure LCNF films.Simultaneously,by regulating the lignin content in LCNF and the properties of L-CQDs,the films exhibit tunable UV blocking and blue-violet light shielding capabilities.Additionally,the prepared BL-CQDs achieve a fluorescence quantum yield of 31.10%,representing a leading level among lignin-derived CQDs.This study will provide a strategy for preparing transparent and full-lignocellulose films with tunable UV-blocking and blue-violet light shielding properties through a design integrating function and structure.
基金supported in part by the National 973Program of China(No.2013CB329205)the National Science Foundation of China(No.61401032)
文摘Visible light positioning （VLP） is an emerging candidate for indoor positioning, which carl simultaneously meet the requirements for accuracy, cost, coverage area, and security. However, intercell interference causcd by light intensity superposition linfits the application of VLP. In this Letter, we propose a united block sequence mapping （UBSM）-based VLP that utilizes superposition to integrate the multidimensional information from dense small cells into 2D information. The experimental result shows that UBSM-based VLP can achieve an accuracy of 1.5 cm with a 0.4 m row spacing and 0.35 m column spacing of LED lights.
